Search results for: film formation

Authors: Yazeed Al-Sheikh

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Pregnancy represents a risk factor in the occurrence of vulvovaginal candidiasis. To investigate the prevalence rate of vaginal carriage of Candida species in Saudi pregnant and non-pregnant women, high vaginal swab (HVS) specimens (707) were examined by direct microscopy (10% KOH and Giemsa staining) and parallel cultured on Sabouraud Dextrose Agar (SDA) as well as on “CHROM agar Candida” medium. As expected, Candida-positive cultures were frequently observed in pregnant-test group (24%) than in non-pregnant group (17%). The frequency of culture positive was correlated to pregnancy (P=0.047), parity (P=0.001), use of contraceptive (P=0.146), or antibiotics (P=0.128), and diabetic-patients (P < 0.0001). Out of 707 HVS examined specimens, 157 specimens were yeast-positive culture (22%) on Sabouraud Dextrose Agar or “CHROM agar Candida”. In comparison, the sensitivities of the direct 10% KOH and the Giemsa stain microscopic examination methods were 84% (132/157) and 95% (149/157) respectively but both with 100% specificity. As for the identity of recovered 157 yeast isolates, based on API 20C biotype carbohydrate assimilation, germ tube and chlamydospore formation, C. albicansand C. glabrata constitute 80.3 and 12.7% respectively. Rates of C. tropicalis, C. kefyr, C. famata or C. utilis were 2.6, 1.3, and 0.6% respectively. Sachromyces cerevisiae and Rhodotorula mucilaginosa yeasts were also encountered at a frequency of 1.3 and 0.6% respectively. Finally, among all recovered 157 yeast-isolates, strains resistant to ketoconazole were not detected, whereas 5% of the C. albicans and as high as 55% of the non-albicans yeast isolates (majority C. glabrata) showed resistance to fluconazole. Our findings may prove helpful for continuous determination of the existing vaginal candidiasis causative species during pregnancy, its lab-diagnosis and/or control and possible measures to minimize the incidence of the disease-associated pre-term delivery.

Keywords: vaginal candidiasis, Candida spp., pregnancy, risk factors, API 20C-yeast biotypes, giemsa stain, antifungal agents

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Authors: Xingmao Ma, Wenjie Sun

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Rice paddies are frequently co-contaminated by arsenic (As) and cadmium (Cd), both of which demonstrate a high propensity for accumulation in rice grains and cause global food safety and public health concern. Even though different agricultural management strategies have been explored for their simultaneous control in rice grains, a viable solution is yet to be developed. Interestingly, several nanoagrichemicals, such as the zinc nanofertilizer and copper nanopesticide have displayed strong potential to reduce As or Cd accumulation in rice tissues. In order to determine whether these nanoagrichemicals can lower the accumulation of both As and Cd in rice, a series of bench studies were performed. Our results show that zinc oxide nanoparticles at 100 mg/Kg significantly lowered both As, and Cd in rice roots and shoots in flood irrigated rice seedlings, while equivalent amount of zinc ions only reduced As concentration in rice shoots. Zinc ions significantly increased Cd concentration in rice shoots by almost 30%. The results demonstrate a unique 'nano-effect' of zinc oxide nanoparticles, which is ascribed to the slow releasing of zinc ions from nanoparticles and the formation of different transformation products in these two treatments. We also evaluated the effect of nanoscale soil amendment, silicon oxide nanoparticles (SiO₂NPs) on the simultaneous reduction in both flooding and alternate wet and dry irrigation scheme. The effect of SiO₂NPs on As and Cd accumulation in rice tissues was strongly affected by the irrigation scheme. While 2000 mg/kg of SiO₂NPs significantly reduced As in rice roots and insignificantly reduced As in rice shoots in flooded rice, it increased As concentration in rice shoots in alternate wet and dry irrigation. In both irrigation scenarios, SiO₂NPs significantly reduced Cd concentration in rice roots, but only reduced Cd concentration in rice shoots in alternate wet and dry irrigation. Our results demonstrate a marked effect of nanoagrichemicals on the accumulation of As and Cd in rice and can be a potential solution to simultaneously control both in certain conditions.

Keywords: arsenic, cadmium, rice, nanoagrichemicals

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Authors: Irina Bondarenko, Olga Vandina

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The theory of evolutionary economics is the basis for preparation and application of methods forming the stock market infrastructure development concept. The authors believe that the basis for the process of formation and development of the stock market model infrastructure in Russia is the theory of large systems. This theory considers the financial market infrastructure as a whole on the basis of macroeconomic approach with the further definition of its aims and objectives. Evaluation of the prospects for interaction of securities market institutions will enable identifying the problems associated with the development of this system. The interaction of elements of the stock market infrastructure allows to reduce the costs and time of transactions, thereby freeing up resources of market participants for more efficient operation. Thus, methodology of the transaction analysis allows to determine the financial infrastructure as a set of specialized institutions that form a modern quasi-stable system. The financial infrastructure, based on international standards, should include trading systems, regulatory and supervisory bodies, rating agencies, settlement, clearing and depository organizations. Distribution of financial assets, reducing the magnitude of transaction costs, increased transparency of the market are promising tasks in the solution for questions of services level and quality increase provided by institutions of the securities market financial infrastructure. In order to improve the efficiency of the regulatory system, it is necessary to provide "standards" for all market participants. The development of a clear regulation for the barrier to the stock market entry and exit, provision of conditions for the development and implementation of new laws regulating the activities of participants in the securities market, as well as formulation of proposals aimed at minimizing risks and costs, will enable the achievement of positive results. The latter will be manifested in increasing the level of market participant security and, accordingly, the attractiveness of this market for investors and issuers.

Keywords: institutional infrastructure, financial assets, regulatory system, stock market, transparency of the market

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Authors: Tafadzwa Makonese, Harold Annegarn, Patricia Forbes

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Residential coal combustion is one of the largest sources of carbonaceous aerosols in the Highveld region of South Africa, significantly affecting the local and regional climate. In this study, we investigated single coal burning particles emitted when using different fire-ignition techniques (top-lit up-draft vs bottom-lit up-draft) and air ventilation rates (defined by the number of air holes above and below the fire grate) in selected informal braziers. Aerosol samples were collected on nucleopore filters at the SeTAR Centre Laboratory, University of Johannesburg. Individual particles (~700) were investigated using a scanning electron microscope equipped with an energy-dispersive X-ray spectroscopy (EDS). Two distinct forms of spherical organic particles (SOPs) were identified, one less oxidized than the other. The particles were further classified into "electronically" dark and bright, according to China et al. [2014]. EDS analysis showed that 70% of the dark spherical organic particles balls had higher (~60%) relative oxygen content than in the bright SOPs. We quantify the morphology of spherical organic particles and classify them into four categories: ~50% are bare single particles; ~35% particles are aggregated and form diffusion accretion chains; 10% have inclusions; and 5% are deformed due to impaction on filter material during sampling. We conclude that there are two distinct kinds of coal burning spherical organic particles and that dark SOPs are less volatile than bright SOPs. We also show that these spherical organic particles are similar in nature and characteristics to tar balls observed in biomass combustion, and that they have the potential to absorb sunlight thereby affecting the earth’s radiative budget and climate. This study provides insights on the mixing states, morphology, and possible formation mechanisms of these organic particles from residential coal combustion in informal stoves.

Keywords: spherical organic particles, residential coal combustion, fixed-bed, aerosols, morphology, stoves

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Authors: Rabindranath Jana, Biswajit Maity, Keka Rana

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The most promising clean energy source is the fuel cell, since it does not generate toxic gases and other hazardous compounds. Again the direct methanol fuel cell (DMFC) is more user-friendly as it is easy to be miniaturized and suited as energy source for automobiles as well as domestic applications and portable devices. And unlike the hydrogen used for some fuel cells, methanol is a liquid that is easy to store and transport in conventional tanks. The most important part of a fuel cell is its membrane. Till now, an overall efficiency for a methanol fuel cell is reported to be about 20 ~ 25%. The lower efficiency of the cell may be due to the critical factors, e.g. slow reaction kinetics at the anode and methanol crossover. The oxidation of methanol is composed of a series of successive reactions creating formaldehyde and formic acid as intermediates that contribute to slow reaction rates and decreased cell voltage. Currently, the investigation of new anode catalysts to improve oxidation reaction rates is an active area of research as it applies to the methanol fuel cell. Surprisingly, there are very limited reports on nanostructured membranes, which are rather simple to manufacture with different tuneable compositions and are expected to allow only the proton permeation but not the methanol due to their molecular sizing effects and affinity to the membrane surface. We have developed a nanostructured fuel cell membrane from polydimethyl siloxane rubber (PDMS), ethylene methyl co-acrylate (EMA) and multi-walled carbon nanotubes (MWNTs). The effect of incorporating different proportions of f-MWNTs in polymer membrane has been studied. The introduction of f-MWNTs in polymer matrix modified the polymer structure, and therefore the properties of the device. The proton conductivity, measured by an AC impedance technique using open-frame and two-electrode cell and methanol permeability of the membranes was found to be dependent on the f-MWNTs loading. The proton conductivity of the membranes increases with increase in concentration of f-MWNTs concentration due to increased content of conductive materials. Measured methanol permeabilities at 60oC were found to be dependant on loading of f-MWNTs. The methanol permeability decreased from 1.5 x 10-6 cm²/s for pure film to 0.8 x 10-7 cm²/s for a membrane containing 0.5wt % f-MWNTs. This is due to increasing proportion of f-MWNTs, the matrix becomes more compact. From DSC melting curves it is clear that the polymer matrix with f-MWNTs is thermally stable. FT-IR studies show good interaction between EMA and f-MWNTs. XRD analysis shows good crystalline behavior of the prepared membranes. Significant cost savings can be achieved when using the blended films which contain less expensive polymers.

Keywords: fuel cell membrane, polydimethyl siloxane rubber, carbon nanotubes, proton conductivity, methanol permeability

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Authors: Joshua Loebner

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Tectonic shifts within the advertising industry regularly and repeatedly present a deluge of data to be intuited across a spectrum of key performance indicators with innumerable interpretations where live campaigns are vivisected to pivot towards coalescence amongst a digital diaspora. But within this amalgam of analytics, validation, and creative campaign manipulation, where do diversity and disability inclusion fit in? In 2018 several major brands were able to answer this question definitely and directly by incorporating people with disabilities into advertisements. Disability inclusion, representation, and portrayals are documented annually across a number of different media, from film to primetime television, but ongoing studies centering on advertising have not been conducted. Symbols and semiotics in advertising often focus on a brand’s features and benefits, but this analysis on advertising and disability shows, how in 2018, creative campaigns and the disability community came together with the goal to continue the momentum and spark conversations. More brands are welcoming inclusion and sharing positive portrayals of intersectional diversity and disability. Within the analysis and surrounding scholarship, a multipoint analysis of each advertisement and meta-interpretation of the research has been conducted to provide data, clarity, and contextualization of insights. This research presents an advertising disability index that can be monitored for trends and shifts in future studies and to provide further comparisons and contrasts of advertisements. An overview of the increasing buying power within the disability community and population changes among this group anchors the significance and size of the minority in the US. When possible, viewpoints from creative teams and advertisers that developed the ads are brought into the research to further establish understanding, meaning, and individuals’ purposeful approaches towards disability inclusion. Finally, the conclusion and discussion present key takeaways to learn from the research, build advocacy and action both within advertising scholarship and the profession. This study, developed into an advertising disability index, will answer questions of how people with disabilities are represented in each ad. In advertising that includes disability, there is a creative pendulum. At one extreme, among many other negative interpretations, people with disables are portrayed in a way that conveys pity, fosters ableism and discrimination, and shows that people with disabilities are less than normal from a societal and cultural perspective. At the other extreme, people with disabilities are portrayed with a type of undue inspiration, considered inspiration porn, or superhuman, otherwise known as supercrip, and in ways that most people with disabilities could never achieve, or don’t want to be seen for. While some ads reflect both extremes, others stood out for non-polarizing inclusion of people with disabilities. This content analysis explores television commercial advertisements to determine the presence of people with disabilities and any other associated disability themes and/or concepts. Content analysis will allow for measuring the presence and interpretation of disability portrayals in each ad.

Keywords: advertising, brand, disability, marketing

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Authors: Akbar Jamali

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According to Hegel’s philosophy, constitution of any given nation is the best expression of its national Self-Consciousness. Since constitution is the place in which freedom and Universal Rights is expressed, and since the essence of Self-consciousness is freedom, the development of self-consciousness and consequently freedom, is the direct cause of the development of constitution. Self-consciousness develops in the human history according to its own internal and external dialectic; therefore, it is essentially a dynamic phenomenon. However, constitution is supposed to be a stable foundation for the legal system of state and society. Therefore, the dilemma is: how the dynamic and contradictory nature of Self-Consciousness is the foundation of constitution that supposed to be the stable base of legal system of state and society. According to Hegel’s philosophy, the contradiction between the dynamic self- consciousness and the static constitution and state has an essential role in the formation of social movements within any given state. Self-consciousness is the phenomenology of Spirit in the human history. Subjective Spirit expresses itself in the different shapes of Self-consciousness in human spirit. These different shapes of self-consciousness must be identical with its contradiction; Objective Spirit. State is the highest form of the objective Spirit. Therefore, state and its foundation namely ‘constitution’ must be identical with Self-consciousness. "Spirit cannot remain forever alienated from its expression." Hegel states. Self-consciousness is the Subjective Spirit, it freely develops according to its internal and external contradictions, but since it must be always identical with its expression namely constitution, its development results to alienation. They way by which self-consciousness became again identical with the constitution determines the nature of legal and political development of any given society and state. In the democratic states, self-consciousness shows itself partially in the public opinion. In the process of election, this public opinion changes the ruling parties that construct the government. In democracies, self-consciousness or subjective spirit is in a dialectical relationship with state or the Objective Spirit. Therefore, it cannot remain alienated with its expression that is political system and its constitution. But, in the autocracies Self-consciousness cannot easily express itself in the government and its constitution. More Self-consciousness develops more it becomes alienated with its expression that is the state and its constitution. Rebel and revolution are the symptom of alienation of Spirit (self-consciousness) with its expression (state and its constitution).

Keywords: alienation, constitution, self-consciousness, spirit

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Authors: Alina Murtishcheva

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The tendency of globalization, challenges to democracy and peace caused by the Russian invasion of Ukraine, and other global conflicts require searching general orientations of governmental development, including local government. The formation of a common theoretical framework for local government guarantees not only of harmonisation of European legislation but also creates prerequisites for the integration of new members into the European Union. One of the most important milestones of such a theoretical framework is the concept of decentralization. Decentralization as a phenomenon is characteristic of most European Union countries at different historical stages. For Ukraine, as a country that has clearly defined a European integration vector of development, understanding not only the legal but also the theoretical basis of decentralisation processes in European countries is an important prerequisite for further reforms. Decentralisation takes different forms, which leads to a variety of understandings in doctrine and, consequently, different interpretations in national legislation. Despite of this, decentralisation is based on common ideas and values such as democracy, participation, the rule of law, and proximity government that are shared by all EU member states. Nevertheless, not all EU countries are currently implementing broad decentralization in their political and legal practices. Some countries are gradually moving in this direction, while others remain quite centralised. There is also a new, insufficiently studied trend today – recentralisation, which can be broadly defined as the strengthening of centralization tendencies in countries that were considered to be decentralized. Consequently, an exploratory theoretical study is needed to identify how the concept of decentralization is combined with the recentralization tendency in EU member states. The purpose of this study is to empirically analyse scientific approaches to the concept of “decentralisation”, to highlight the tendency of recentralisation and its consequences, to analyse Ukraine's experience in the field of decentralisation of public power, and to outline the prospects for further development of Ukrainian legislation in this area.

Keywords: centralization, decentralization, local government, recentralization, reforms

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Authors: N. Stoeva, I. Spassova, R. Nickolov, M. Khristova

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Exhaust gases from stationary and mobile combustion sources contain nitrogen oxides that cause a variety of environmentally harmful effects. The most common approach of their elimination is the catalytic reaction in the exhaust using various reduction agents such as NH3, CO and hydrocarbons. Transition metals (Co, Ni, Cu, etc.) are the most widely used as active components for deposition on various supports. However, since the interaction between different catalyst components have been extensively studied in different types of reaction systems, the possible cooperation between active components and the support material and the underlying mechanisms have not been thoroughly investigated. The support structure may affect how these materials maintain an active phase. The objective is to investigate the addition of carbonaceous materials with different nature and texture characteristics on the properties of the resulting silica-carbon support and how it influences of the catalytic properties of the supported copper and cobalt catalysts for reduction of NO with CO. The versatility of the physico-chemical properties of the composites and the supported copper and cobalt catalysts are discussed with an emphasis on the relationship of the properties with the catalytic performance. The catalysts were prepared by sol-gel process and were characterized by XRD, XPS, AAS and BET analysis. The catalytic experiments were carried out in catalytic flow apparatus with isothermal flow reactor in the temperature range 20–300оС. After the catalytic test temperature-programmed desorption (TPD) was carried out. The transient response method was used to study the interaction of the gas phase with the catalyst surface. The role of the interaction between the support and the active phase on the catalyst’s activity in the studied reaction was discussed. We suppose the carbon particles with small sizes to participate in the formation of the active sites for the reduction of NO with CO along with their effect on the kind of deposited metal oxide phase. The existence of micropore texture for some of composites also influences by mass-transfer limitations.

Keywords: catalysts, no reduction, composites, bet analysis

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Authors: Natsuki Kishizawa, Keiko Nakano, Hussam Organji, Amer Shaiban, Mohammad Albeirutty

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One of the most important tasks in operating desalination plants using a reverse osmosis (RO) method is preventing RO membrane fouling caused by foulants found in seawater. Optimal design of the pre-treatment process of RO process for plants enables the reduction of foulants. Therefore, a quantitative evaluation of the fouling risk in pre-treated water, which is fed to RO, is required for optimal design. Some measurement methods for water quality such as silt density index (SDI) and total organic carbon (TOC) have been conservatively applied for evaluations. However, these methods have not been effective in some situations for evaluating the fouling risk of RO feed water. Furthermore, stable management of plants will be possible by alerts and appropriate control of the pre-treatment process by using the method if it can be applied to the inline monitoring system for the fouling risk of RO feed water. The purpose of this study is to develop a method to evaluate the fouling risk of RO feed water. We applied a quartz crystal microbalance (QCM) to measure the amount of foulants found in seawater using a sensor whose surface is coated with polyamide thin film, which is the main material of a RO membrane. The increase of the weight of the sensor after a certain length of time in which the sample water passes indicates the fouling risk of the sample directly. We classified the values as “FP: Fouling Potential”. The characteristics of the method are to measure the very small amount of substances in seawater in a short time: < 2h, and from a small volume of the sample water: < 50mL. Using some RO cell filtration units, a higher correlation between the pressure increase given by RO fouling and the FP from the method than SDI and TOC was confirmed in the laboratory-scale test. Then, to establish the correlation in the actual bench-scale RO membrane module, and to confirm the feasibility of the monitoring system as a control tool for the pre-treatment process, we have started a long-term test at an experimental desalination site by the Red Sea in Jeddah, Kingdom of Saudi Arabia. Implementing inline equipment for the method made it possible to measure FP intermittently (4 times per day) and automatically. Moreover, for two 3-month long operations, the RO operation pressure among feed water samples of different qualities was compared. The pressure increase through a RO membrane module was observed at a high FP RO unit in which feed water was treated by a cartridge filter only. On the other hand, the pressure increase was not observed at a low FP RO unit in which feed water was treated by an ultra-filter during the operation. Therefore, the correlation in an actual scale RO membrane was established in two runs of two types of feed water. The result suggested that the FP method enables the evaluation of the fouling risk of RO feed water.

Keywords: fouling, monitoring, QCM, water quality

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Authors: Kyong-Ku Yun, Seung-Yeon Han, Kyeo-Re Lee

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Silica fume which is a super-fine byproduct of ferrosilicon or silicon metal has a filling effect on micro-air voids or a transition zone in a hardened cement paste by appropriate mixing, placement, and curing. It, also, has a Pozzolan reaction which enhances the interior density of the hydrated cement paste through a formation of calcium silicate hydroxide. When substituting cement with silica fume, it improves water tightness and durability by filling effect and Pozzolan reaction. However, it needs high range water reducer or super-plasticizer to distribute silica fume into a concrete because of its finesses and high specific surface area. In order to distribute into concrete evenly, cement manufacturers make a pre-blended cement of silica fume and provide to a market. However, a special mixing procedures and another transportation charge another cost and this result in a high price of pre-blended cement of silica fume. The purpose of this dissertation was to investigate the dispersion of silica fume by air slurry and its effect on the mechanical properties of at ready-mixed concrete. The results are as follows: A dispersion effect of silica fume was measured from an analysis of standard deviation for compressive strength test results. It showed that the standard deviation decreased as the air bubble content increased, which means that the dispersion became better as the air bubble content increased. The test result of rapid chloride permeability test showed that permeability resistance increased as the percentages of silica fume increased, but the permeability resistance decreased as the quantity of mixing air bubble increased. The image analysis showed that a spacing factor decreased and a specific surface area increased as the quantity of mixing air bubble increased.

Keywords: cellular sprayed concrete, silica fume, deviation, permeability

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Authors: Gennaro Marino

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This paper concerns a case of a 10.75 inch diameter buried gas transmission line which was exposed to mine subsidence ground movements. The pipeline was buried about 4ft. below the surface with maximum operating pressure of 1440 psi. The mine subsidence movement was the result of long walling ore at a depth of approximately 1600 ft. As ore extraction progressed, the stress in the monitored pipeline worsened and was approaching unacceptable levels. The excessive pipe compression resulted when it was exposed to the compression zone of subsidence basin created by mining. The pipe stress reached a significant compressive level due to the extensive length of the pipe exposed to frictional ground-pipe slip resistance. The backfill ground movement slip resistance depends on normal stress around the pipe, the rate of slip, and the backfill characteristics. Normal stress depends on the burial depth of the backfill density and the lateral subsidence induced stress. The backfill in this site has a soil dry density of approximately 90 PCF. A suite of direct shear tests was conducted a residual friction angle of 36 was determined for the ambient backfill. These tests showed that the residual shearing resistance was reached within a fraction of an inch. The pipe was coated with fusion-bonded epoxy, so friction reduce factory of 0.6 can be considered. To relieve ground movement induced compressive stress, the line was uncovered. As more of the pipeline was exposed, the pipe abruptly bowed in the excavation. An analysis of this pipe formation which was performed is provided in this paper. Also discussed in this paper are ways to mitigate this pipe deformation or upheaval buckling from occurring. Keywords: Pipe Upheaval, Pipe Buckling, Ground subsidence, Buried Pipeline, Pipe Stress Mitigation.

Keywords: pipe upheaval, pipe buckling, ground subsidence, buried pipeline, pipe stress mitigation

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Authors: Lakshmikanth Reddy, Bhavin Desai, Chandrakala Kari, Sanjay Sarkar, Pradeep Binu

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The sulphur dioxide gases generated as a by-product of smelting and converting operations of copper concentrate contain selenium apart from zinc, lead, copper, cadmium, bismuth, antimony, and arsenic. The gaseous stream is treated in waste heat boiler, electrostatic precipitator and scrubbers to remove coarse particulate matter in order to produce commercial grade sulfuric acid. The gas cleaning section of the acid plant uses water to scrub the smelting gases. After scrubbing, the sludge settled at the bottom of the scrubber, was analyzed in present investigation. It was found to contain 30 to 40 wt% copper and selenium up to 40 wt% selenium. The sludge collected during blow-down is directly recycled to the smelter for copper recovery. However, the selenium is expected to again vaporize due to high oxidation potential during smelting and converting, causing accumulation of selenium in sludge. In present investigation, a roasting process has been developed to recover the selenium before the copper recovery from the sludge at smelter. Selenium is associated with copper in sludge as copper selenide, as determined by X-ray diffraction and electron microscopy. The thermodynamic and thermos-gravimetry study revealed that the copper selenide phase present in the sludge was amenable to oxidation at 600°C forming oxides of copper and selenium (Cu-Se-O). However, the dissociation of selenium from the copper oxide was made possible by sulfatation using sulfur dioxide between 450 to 600°C, resulting into the formation of CuSO₄ (s) and SeO₂ (g). Lab scale trials were carried out in vertical tubular furnace to determine the optimum roasting conditions with respect to roasting time, temperature and molar ratio of O₂:SO₂. Using these optimum conditions, selenium up to 90 wt% in the form of SeO₂ vapors could be recovered from the sludge in a large-scale commercial roaster. Roasted sludge free from the selenium and containing oxides and sulfates of copper could now be recycled in the smelter for copper recovery.

Keywords: copper, selenium, copper selenide, sludge, roasting, SeO₂

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Authors: Tamaz Mdzinarashvili, Mariam Khvedelidze, Eka Shekiladze, Salome Chinchaladze, Mariam Mdzinarashvili

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The work is about the preparation of calcium-containing 1,2-Dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and 1,2-Dipalmitoyl-sn-glycero-3-phosphatidic acid (DPPA) and their calorimetric study. In order to prepare these complex liposomes, for the first stage it is necessary for ligands and lipids to directly interact, followed by the addition of pH-buffered water or solvent at temperatures slightly above the liposome phase transition temperature. The resulting mixture is briefly but vigorously shaken and then transformed into liposomes of the desired size using an extruder. Particle sizing and calorimetry were used to evaluate liposome formation. We determined the possible structure of calcium-containing liposomes made by our new technology and determined their thermostability. The paper provides calculations showing how many phospholipid molecules are required to make a 200 nm diameter liposome. Calculations showed that 33x10³ lipid molecules are needed to prepare one DPPA and DPPC liposome. Based on the calorimetric experiments, we determined that the structure of uncomplexed DPPA liposomes is unilaminar (one double layer), while DPPC liposome is a nanoparticle with a multilaminar (multilayer) structure. This was determined by the cooperativity of the heat absorption peak. Calorimetric studies of calcium liposomes made by our technology showed that calcium ions are placed in the multilaminar structure of the DPPC liposome. Calcium ions also formed a complex in the DPPA liposome structure, moreover, calcium made the DPPA liposome multilaminar, since the cooperative narrow heat absorption peak was transformed into a three-peak heat absorption peak. Since both types of liposomes in complex with calcium ions present a multilaminar structure, where the number of lipid heads in one particle is large, the number of calcium ions in one particle will also be increased. That makes it possible to use these nanoparticles as transporters of a large amount of calcium ions in a living organism.

Keywords: calcium, liposomes, thermodynamic parameters, calorimetry

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Authors: Mohammad Alkhatatbeh, Nehad Ayoub, Nizar Mhaidat, Nesreen Saadeh, Lisa Lincz

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CD36 is involved in the development of atherosclerosis by enhancing macrophage endocytosis of oxidized-low density lipoproteins and foam cell formation. Soluble CD36 (sCD36) was found to be elevated in type 2 diabetic patients and was supposed to act as a marker of insulin resistance and atherosclerosis. In young subjects, sCD36 was associated with cardiovascular risk factors including obesity and hypertriglyceridemia. This study was conducted to further investigate the relationship between plasma sCD36 and cardiovascular risk factors among middle-aged patients with metabolic syndrome (MetS) and healthy controls. SCD36 concentrations were determined by enzyme-linked immunosorbent assays (ELISA) for 41 patients with MetS and 36 healthy controls. Data for other variables were obtained from patients' medical records. SCD36 concentrations were relatively low compared to most other studies and were not significantly different between the MetS group and controls (P-value=0.17). SCD36 was also not correlated with age, body mass index, glucose, lipid profile, serum electrolytes and blood counts. SCD36 was not significantly different between subjects with obesity, hyperglycemia, dyslipidemia, hypertension or cardiovascular disease and those without these abnormalities (P-value > 0.05). The inconsistency between results reported in this study and other studies may be unique to the study population or be a result of the lack of a reliable standardized method for determining absolute sCD36 concentrations. However, further investigations are required to assess CD36 tissue expression in the study population and to assess the accuracy of various commercially available sCD36 ELISA kits. Thus, the availability of a standardized simple sCD36 ELISA that could be performed in any basic laboratory would be more favorable to the specialized flow cytometry methods that detect CD36+ microparticles if it was to be used as a biomarker.

Keywords: metabolic syndrome, CD36, cardiovascular risk, obesity, type 2 diabetes mellitus

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Authors: Hafida Ferfera-Harrar, Nacera Aiouaz, Nassima Dairi

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Super absorbents polymers received much attention and are used in many fields because of their superior characters to traditional absorbents, e.g., sponge and cotton. So, it is very important but challenging to prepare highly and fast-swelling super absorbents. A reliable, efficient and low-cost technique for removing heavy metal ions from waste water is the adsorption using bio-adsorbents obtained from biological materials, such as polysaccharides-based hydrogels super absorbents. In this study, novel multi-functional super absorbent composites type semi-interpenetrating polymer networks (Semi-IPNs) were prepared via graft polymerization of acrylamide onto chitosan backbone in presence of gelatin, CTS-g-PAAm/Ge, using potassium persulfate and N,N’ -methylenebisacrylamide as initiator and cross linker, respectively. These hydrogels were also partially hydrolyzed to achieve superabsorbents with ampholytic properties and uppermost swelling capacity. The formation of the grafted network was evidenced by Fourier Transform Infrared Spectroscopy (ATR-FTIR) and thermo gravimetric Analysis (TGA). The porous structures were observed by Scanning Electron Microscope (SEM). From TGA analysis, it was concluded that the incorporation of the Ge in the CTS-g-PAAm network has marginally affected its thermal stability. The effect of gelatin content on the swelling capacities of these super absorbent composites was examined in various media (distilled water, saline and pH-solutions).The water absorbency was enhanced by adding Ge in the network, where the optimum value was reached at 2 wt. % of Ge. Their hydrolysis has not only greatly optimized their absorption capacity but also improved the swelling kinetic. These materials have also showed reswelling ability. We believe that these super-absorbing materials would be very effective for the adsorption of harmful metal ions from waste water.

Keywords: chitosan, gelatin, superabsorbent, water absorbency

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Authors: Sohal Latif

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Solar power is in the form of photovoltaic, also known as PV, which is a form of renewable energy that applies solar panels in producing electricity from the sun. It has a vital role in fulfilling the present need for clean and renewable energy to get rid of conventional and non-renewable energy sources that emit high levels of greenhouse gases. Solar energy is embraced because of its availability, easy accessibility, and effectiveness in the provision of power, chiefly in country areas. In solar charging, device charge entails a change of light power into electricity using photovoltaic or PV panels, which supply direct current electric power or DC. Here, the solar charge controller has a very crucial role to play regarding the voltages and the currents coming from the solar panels to take up the changing needs of a battery without overcharging the same. Certain devices, such as inverters, are required to transform the DC power produced by the solar panels into an AC to serve the normal electrical appliances and the current power network. This project was initiated for a project of a solar charge controller and power converter with the MULTISIM. The formation of this project begins with a literature survey to obtain basic knowledge about power converters, charge controllers, and photovoltaic systems. Fundamentals of the operation of solar panels include the process by which light is converted into electricity and a comparison of PWM and MPPT chargers with controllers. Knowledge of rectifiers is built to help achieve AC-to-DC and DC-AC change. Choosing a resistor, capacitance, MOSFET, and OP-AMP is done by the need of the system. The circuit diagrams of converters and charge controllers are designed using the Multisim program. Pulse width modulation, Bubba oscillator circuit, and inverter circuits are modeled and simulated. In the subsequent steps, the analysis of the simulation outcomes indicates the efficiency of the intended converter systems. The various outputs from the different configurations, with the transformer incorporated as well as without it, are then monitored for effective power conversion as well as power regulation.

Keywords: solar charge controller, MULTISIM, converter, inverter

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Authors: Awdhesh Yadav, P. S. Saravanamurthy, Shaikh Tayyaba, Uma Shah, Ashok Agarwal

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Objectives: HIV interventions in India has leveraged Self-Help Group (SHG) as one of the key strategies under structural intervention to empower female sex workers (FSW) to reduce their risk exposure and vulnerability to STI/HIV. Understanding the role of SHGs in light of the evolving dynamics of sex work needs to be delved into to strategize HIV interventions among FSWs in India. This paper aims to study the HIV program outcome among the FSWs associated with SHGs and FSWs not associated with SHGs in Thane, Maharashtra. Study Design: This cross-sectional study, was undertaken from the Behavioral Tracking Survey (BTS) conducted among 503 FSWs in Thane in 2015. Two-stage probability based conventional sampling was done for selection of brothel and bar based FSWs, while Time Location Cluster (TLC) sampling was done for home, lodge and street-based sex workers. Methods: Bivariate and multivariate logistic regression were performed to compare and contrast between FSWs associated with SHG and those not associated with SHG with respect to the utilization of HIV related services by them. ‘Condom use’, ‘consistent condom use’, ‘contact with peer-educators’, ‘counseling sessions’ and ‘HIV testing’ were chosen as indicators on HIV service utilization. Results: 8% (38) of FSWs are registered with SHG; 92% aged ≥ 25 years, 47% illiterate, and 71% are currently married. The likelihood of utilizing HIV services including, knowledge on HIV/AIDS and its mode of transmission (OR:5.54; CI: 1.87-16.60; p < 0.05),accessed drop-in Centre (OR: 6.53; CI: 2.15-19.88; p < 0.10), heard about joint health camps (OR: 4.71; CI:2.12-10.46); p < 0.05), negotiated or stood up against police/broker/local goonda/clients (OR: 2.26; CI: 1.08-4.73; p < 0.05), turned away clients when they refused to use condom during sex (OR: 3.76; CI: 1.27-11.15; p < 0.05) and heard of ART (OR; 4.55; CI: 2.18-9.48; p < 0.01) were higher among FSWs associated with SHG in comparison to FSWs not associated with SHG. Conclusions: Considering the improved HIV program outcomes among FSWs associated with SHG; HIV interventions among FSWs could consider facilitating the formation of SHGs with FSWs as one of the key strategies to empower the community for ensuring better program outcomes.

Keywords: empowerment, female sex workers, HIV, Thane, self-help group

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Authors: Jan Luxa, Vlastimil Mazanek, Petr Malinsky, Alexander Romanenko, Mariapompea Cutroneo, Vladimir Havranek, Josef Novak, Eva Stepanovska, Anna Mackova, Zdenek Sofer

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Using accelerated energetic ions is an interesting method for the introduction of structural changes in various carbon-based materials. This way, the properties can be altered in two ways: a) the ions lead to the formation of conductive pathways in graphene oxide structures due to the elimination of oxygen functionalities and b) doping with selected ions to form metal nanoclusters, thus increasing the conductivity. In this work, energetic beams were employed in two ways to prepare capacitor structures in graphene oxide (GO), reduced graphene oxide (rGO) and polyimide (PI) on a micro-scale. The first method revolved around using ion beam writing with a focused ion beam, and the method involved ion implantation via a polymeric mask. To prepare the polymeric mask, a direct spin-coating of PMMA on top of the foils was used. Subsequently, proton beam writing and development in isopropyl alcohol were employed. Finally, the mask was removed using acetone solvent. All three materials were exposed to ion beams with an energy of 2.5-5 MeV and an ion fluence of 3.75x10¹⁴ cm-² (1800 nC.mm-²). Thus, prepared microstructures were thoroughly characterized by various analytical methods, including Scanning electron microscopy (SEM) with Energy-Dispersive X-ray spectroscopy (EDS), X-ray Photoelectron spectroscopy (XPS), micro-Raman spectroscopy, Rutherford Back-scattering Spectroscopy (RBS) and Elastic Recoil Detection Analysis (ERDA) spectroscopy. Finally, these materials were employed and tested as sensors for humidity using electrical conductivity measurements. The results clearly demonstrate that the type of ions, their energy and fluence all have a significant influence on the sensory properties of thus prepared sensors.

Keywords: graphene, graphene oxide, polyimide, ion implantation, sensors

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Authors: Camilo A. Guerrero-Martin, Erik Montes Paez, Marcia C. K. Oliveira, Jonathan Campos, Elizabete F. Lucas

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Asphaltenes precipitation is considered as a formation damage problem, which can reduce the oil recovery factor. It fouls piping and surface installations, as well as cause serious flow assurance complications and decline oil well production. Therefore, researchers have shown an interest in chemical treatments to control this phenomenon. The aim of this paper is to assess the asphaltenes precipitation onset of crude oils in the presence of cardanol, by titrating the crude with n-heptane. Moreover, based on this results obtained at atmosphere pressure, the asphaltenes precipitation onset pressure were calculated to predict asphaltenes precipitation in the reservoir, by using differential liberation and refractive index data of the oils. The influence of cardanol concentrations in the asphaltenes stabilization of three Brazilian crude oils samples (with similar API densities) was studied. Therefore, four formulations of cardanol in toluene were prepared: 0, 3, 5, 10 and 15 m/m%. The formulations were added to the crude at 2:98 ratio. The petroleum samples were characterized by API density, elemental analysis and differential liberation test. The asphaltenes precipitation onset (APO) was determined by titrating with n-heptane and monitoring with near-infrared (NIR). UV-Vis spectroscopy experiments were also done to assess the precipitate asphaltenes content. The asphaltenes precipitation envelopes (APE) were also determined by numerical simulation (Multiflash). In addition, the adequate artificial lift systems (ALS) for the oils were selected. It was based on the downhole well profile and a screening methodology. Finally, the oil flowrates were modelling by NODAL analysis production system in the PIPESIM software. The results of this study show that the asphaltenes precipitation onset of the crude oils were 2.2, 2.3 and 6.0 mL of n-heptane/g of oil. The cardanol was an effective inhibitor of asphaltenes precipitation for the crude oils used in this study, since it displaces the precipitation pressure of the oil to lower values. This indicates that cardanol can increase the oil wells productivity.

Keywords: asphaltenes, NODAL analysis production system, precipitation pressure onset, inhibitory molecule

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Authors: Ana Claudia Muniz Rennó, Karina Nogueira

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This study aimed to investigate the in vivo tissue response of the introduction of the bioactive mesh (BM) scaffolds using a model of tibial bone defect implants in rats. Although a previous in vivo study demonstrated a highly positive response of particulate bioactive materials in the morphological and biomechanical properties of the bone callus, the effects of material with superior bioactivity, present in form of meshes have not been studied yet. Eighty male Wistar rats with 3 mm tibial defects were used. Animals were divided into four groups: intact group (IG) – tibia without any injury; bone defect day zero (0dD) – bone defects, sacrificed immediately after injury; bone defect control group (CG) – bone defects without any filler and bone defect filled with BM scaffold. The animals of BM and CG groups were sacrificed 15, 30 and 45 days post-injury to compare the temporal-special effects of the scaffolds on bone healing. The histological analysis revealed an organized newly formed bone at 30 and 45 days post-surgery in the BM. Also, this group presented an increased COX-2 expression on days 15 and 30 post-surgery. Furthermore, the immunohistochemistry analysis revealed that, BM presented a positive immunoexpression of RUNX-2 during all periods evaluated. The biomechanical analysis revealed that at 15 day after surgery, no significant statistically difference was observed between BM and CG and both groups had significantly higher values of maximal load compared to 0dG and significantly lower values than IG. On days 30 and 45 post-surgery, BM presented statistically lower values of maximal load compared to the CG. Nevertheless, at the same periods, BM did not show statistically significant difference compared to the IG maximal load values (p > 0, 05). Our results revealed that the implantation of the BM scaffolds was effective in stimulating newly bone formation.

Keywords: bone, biomaterials, scaffolds, cartilage

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Authors: I. Nava-Arenas, N. Ruiz-Ordaz, C. J. Galindez-Mayer, M. L. Luna-Guido, S. L. Ruiz-López, A. Cabrera-Orozco, D. Nava-Arenas

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Among the most important herbicides, the organochlorine compounds are of considerable interest due to their recalcitrance to the chemical, biological, and photolytic degradation, their persistence in the environment, their mobility, and their bioacummulation. The most widely used herbicides in North America are primarily 2,4-dichlorophenoxyacetic acid (2,4-D), the triazines (atrazine and simazine), and to a lesser extent diuron. The contamination of soils and water bodies frequently occurs by mixtures of these xenobiotics. For this reason, in this work, the operational stability to changes in the composition of the medium supplied to an aerobic biofilm reactor was studied. The reactor was packed with fragments of volcanic rock that retained a complex microbial film, able to degrade a mixture of organochlorine herbicides atrazine, simazine, diuron and 2,4-D, and whose members have microbial genes encoding the main catabolic enzymes atzABCD, tfdACD and puhB. To acclimate the attached microbial community, the biofilm reactor was fed continuously with a mineral minimal medium containing the herbicides (in mg•L-1): diuron, 20.4; atrazine, 14.2, simazine, 11.4, and 2,4-D, 59.7, as carbon and nitrogen sources. Throughout the bioprocess, removal efficiencies of 92-100% for herbicides, 78-90% for COD, 92-96% for TOC and 61-83% for dehalogenation were reached. In the microbial community, the genes encoding catabolic enzymes of different herbicides tfdACD, puhB and, occasionally, the genes atzA and atzC were detected. After the acclimatization, the triazine herbicides were eliminated from the mixture formulation. Volumetric loading rates of the mixture 2,4-D and diuron were continuously supplied to the reactor (1.9-21.5 mg herbicides •L-1 •h-1). Along the bioprocess, the removal efficiencies obtained were 86-100% for the mixture of herbicides, 63-94% for for COD, 90-100% for COT, and dehalogenation values of 63-100%. It was also observed that the genes encoding the enzymes in the catabolism of both herbicides, tfdACD and puhB, were consistently detected; and, occasionally, the atzA and atzC. Subsequently, the triazine herbicide atrazine and simazine were restored to the medium supply. Different volumetric charges of this mixture were continuously fed to the reactor (2.9 to 12.6 mg herbicides •L-1 •h-1). During this new treatment process, removal efficiencies of 65-95% for the mixture of herbicides, 63-92% for COD, 66-89% for TOC and 73-94% of dehalogenation were observed. In this last case, the genes tfdACD, puhB and atzABC encoding for the enzymes involved in the catabolism of the distinct herbicides were consistently detected. The atzD gene, encoding the cyanuric hydrolase enzyme, could not be detected, though it was determined that there was partial degradation of cyanuric acid. In general, the community in the biofilm reactor showed some catabolic stability, adapting to changes in loading rates and composition of the mixture of herbicides, and preserving their ability to degrade the four herbicides tested; although, there was a significant delay in the response time to recover to degradation of the herbicides.

Keywords: biodegradation, biofilm reactor, microbial community, organochlorine herbicides

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Authors: Ying Sun, Biao Cheng, Qing Lu, Xuefei Tao, Xiaoyu Lai, Cheng Guo, Dan Wang

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Fibrinogen-like protein 2 (FGL2) has recently been identified to play an important role in inflammatory diseases such as atherosclerosis through a thrombin-dependent manner. Here, a murine monoclonal antibody was raised against the critical residue Ser(89) of FGL2, and the effects of the anti-FGL2 mAb (SPF89) were analyzed in human umbilical vein endothelial cells (HUVECs) and THP-1 cells. Firstly, it was proved that SPF89, which belongs to the IgG1 subtype with a KD value of 44.5 pM, could specifically show the expression levels of protein FGL2 in different cell lines of known target gene status. The lipopolysaccharide (LPS)-mediated endothelial cell proliferation was significantly inhibited with a decline of phosphorylation nuclear factor-κB (NF-κB) in a dose-dependent manner after SPF89 treatment. Furthermore, SPF89 reduced LPS-induced expression of adhesion molecules and inflammatory cytokines such as vascular cell adhesion molecule-1, tumor necrosis factor-α, Matrix metalloproteinase MMP-2, Integrin αvβ3, and interleukin-6 in HUVECs. In macrophage-like THP-1 cells, SPF89 effectively inhibited LPS and low-density lipoprotein-induced foam cell formation. However, these anti-inflammatory and anti-atherosclerotic effects of anti-FGL2 mAb in HUVECs and THP-1 cells were significantly reduced after treatment with an NF-κB inhibitor PDTC. All the above suggest, by efficiently inhibiting LPS-induced pro-inflammatory effects in vascular endothelial cells by attenuating NF-κB dependent pathway, the new anti-FGL2 mAb SPF89 could to be a potential therapeutic candidate for protecting the vascular endothelium against inflammatory diseases such as atherosclerosis. This work was supported by the Program of Sichuan Science and Technology Department (2017FZ0069) and Collaborative Innovation Program of Sichuan for Elderly Care and Health(YLZBZ1511).

Keywords: monoclonal antibody, fibrinogen like protein 2, inflammation, endothelial cells

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Authors: S. AliReza Mirghasemi, Zameer Hussain, Mohammad Saleh Sadeghi, Narges Rahimi Gabaran, Mohamadreza Baghaban Eslaminejad

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Background: Despite promising results have shown by osteogenic cell-based demineralized bone matrix composites, they need to be optimized for grafts that act as structural frameworks in load-bearing defects. The purpose of this experiment is to determine the effect of bone-marrow-mesenchymal-stem-cells seeding on partially demineralized laser-perforated structural allografts that have been implanted in critical femoral defects. Materials and Methods: P3 stem cells were used for graft seeding. Laser perforation in four rows of three holes was achieved. Cell-seeded grafts were incubated for one hour until they were planted into the defect. We used four types of grafts: partially demineralized only (Donly), partially demineralized stem cell seeded (DST), partially demineralized laser-perforated (DLP), and partially demineralized laser-perforated stem cell seeded (DLPST). histologic and histomorphometric analysis were performed at 12 weeks. Results: Partially demineralized laser-perforated had the highest woven bone formation within graft limits, stem cell seeded demineralized laser-perforated remained intact, and the difference between partially demineralized only and partially demineralized stem cell seeded was insignificant. At interface, partially demineralized laser-perforated and partially demineralized only had comparable osteogenesis, but partially demineralized stem cell seeded was inferior. The interface in stem cell seeded demineralized laser-perforated was almost replaced by distinct endochondral osteogenesis with higher angiogenesis in the vicinity. Partially demineralized stem cell seeded and stem cell seeded demineralized laser-perforated graft surfaces had extra vessel-ingrowth-like porosities, a sign of delayed resorption. Conclusion: This demonstrates that simple cell-based composites are not optimal and necessitates the supplementation of synergistic stipulations and surface changes.

Keywords: structural bone allograft, partial demineralization, laser perforation, mesenchymal stem cell

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Authors: M. Venegas, M. De Vega, N. García-Hernando

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Absorption cooling chillers have received growing attention over the past few decades as they allow the use of low-grade heat to produce the cooling effect. The combination of this technology with solar thermal energy in the summer period can reduce the electricity consumption peak due to air-conditioning. One of the main components, the absorber, is designed for simultaneous heat and mass transfer. Usually, shell and tubes heat exchangers are used, which are large and heavy. Cooling water from a cooling tower is conventionally used to extract the heat released during the absorption and condensation processes. These are clear inconvenient for the generalization of the absorption technology use, limiting its benefits in the contribution to the reduction in CO2 emissions, particularly for the H2O-LiBr solution which can work with low heat temperature sources as provided by solar panels. In the present work a promising new technology is under study, consisting in the use of membrane contactors in adiabatic microchannel mass exchangers. The configuration here proposed consists in one or several modules (depending on the cooling capacity of the chiller) that contain two vapour channels, separated from the solution by adjacent microporous membranes. The solution is confined in rectangular microchannels. A plastic or synthetic wall separates the solution channels between them. The solution entering the absorber is previously subcooled using ambient air. In this way, the need for a cooling tower is avoided. A model of the configuration proposed is developed based on mass and energy balances and some correlations were selected to predict the heat and mass transfer coefficients. The concentration and temperatures along the channels cannot be explicitly determined from the set of equations obtained. For this reason, the equations were implemented in a computer code using Engineering Equation Solver software, EES™. With the aim of minimizing the absorber volume to reduce the size of absorption cooling chillers, the ratio between the cooling power of the chiller and the absorber volume (R) is calculated. Its variation is shown along the solution channels, allowing its optimization for selected operating conditions. For the case considered the solution channel length is recommended to be lower than 3 cm. Maximum values of R obtained in this work are higher than the ones found in optimized horizontal falling film absorbers using the same solution. Results obtained also show the variation of R and the chiller efficiency (COP) for different ambient temperatures and desorption temperatures typically obtained using flat plate solar collectors. The configuration proposed of adiabatic membrane-based absorber using ambient air to subcool the solution is a good technology to reduce the size of the absorption chillers, allowing the use of low temperature solar heat and avoiding the need for cooling towers.

Keywords: adiabatic absorption, air-cooled, membrane, solar thermal energy

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Authors: Ganesh R. Bhand, N. B. Chaure

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Cadmium selenide (CdSe) quantum dots (QDs) were prepared by solvothermal route. Subsequently a inorganic QDs-organic semiconductor (copper phthalocyanine) nanocomposite (i.e CuPc:CdSe nanocomposites) were produced by different concentration of QDs varied in CuPc. The nanocomposite thin films have been prepared by means of spin coating technique. The optical, structural and morphological properties of nanocomposite films have been investigated. The transmission electron microscopy (TEM) confirmed the formation of QDs having average size of  4 nm. The X-ray diffraction pattern exhibits cubic crystal structure of CdSe with reflection to (111), (220) and (311) at 25.4ᵒ, 42.2ᵒ and 49.6ᵒ respectively. The additional peak observed at lower angle at 6.9ᵒ in nanocomposite thin films are associated to CuPc. The field emission scanning electron microscopy (FESEM) observed that surface morphology varied in increasing concentration of CdSe QDs. The obtained nanocomposite show significant improvement in the thermal stability as compared to the pure CuPc indicated by thermo-gravimetric analysis (TGA) in thermograph. The effect in the Raman spectra of composites samples gives a confirm evidence of homogenous dispersion of CdSe in the CuPc matrix and their strong interaction between them to promotes charge transfer property. The success of reaction between composite was confirmed by Fourier transform infrared spectroscopy (FTIR). The photo physical properties were studied using UV - visible spectroscopy. The enhancement of the optical absorption in visible region for nanocomposite layer was observed with increasing the concentration of CdSe in CuPc. This composite may obtain the maximized interface between QDs and polymer for efficient charge separation and enhance the charge transport. Such nanocomposite films for potential application in fabrication of hybrid solar cell with improved power conversion efficiency.

Keywords: CdSe QDs, cupper phthalocyanine, FTIR, optical absorption

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Authors: Radzuan Junin, Dayang Zulaika A. Hasbollah

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The increasing amount of greenhouse gasses in the atmosphere recently has become one of the discussed topics in relation with world’s concern on climate change. Developing countries’ emissions (such as Malaysia) are now seen to surpass developed country’s emissions due to rapid economic development growth in recent decades. This paper presents the potential storage sites suitability and storage capacity assessment for CO2 sequestration in sedimentary basins of Malaysia. This study is the first of its kind that made an identification of potential storage sites and assessment of CO2 storage capacity within the deep saline aquifers in the country. The CO2 storage capacity in saline formation assessment was conducted based on the method for quick assessment of CO2 storage capacity in closed, and semi-closed saline formations modified to suit the geology setting of Malaysia. Then, an integrated approach that involved geographic information systems (GIS) analysis and field data assessment was adopted to provide the potential storage sites and its capacity for CO2 sequestration. This study concentrated on the assessment of major sedimentary basins in Malaysia both onshore and offshore where potential geological formations which CO2 could be stored exist below 800 meters and where suitable sealing formations are present. Based on regional study and amount of data available, there are 14 sedimentary basins all around Malaysia that has been identified as potential CO2 storage. Meanwhile, from the screening and ranking exercises, it is obvious that Malay Basin, Central Luconia Province, West Baram Delta and Balingian Province are respectively ranked as the top four in the ranking system for CO2 storage. 27% of sedimentary basins in Malaysia were evaluated as high potential area for CO2 storage. This study should provide a basis for further work to reduce the uncertainty in these estimates and also provide support to policy makers on future planning of carbon capture and sequestration (CCS) projects in Malaysia.

Keywords: CO₂ storage, deep saline aquifer, GIS, sedimentary basin

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Authors: Min Han, Di Wu, Lin Yuan, Fei Liu

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Mechanical sensors have undergone a continuous evolution and have become an important part of many industries, ranging from manufacturing to process, chemicals, machinery, health-care, environmental monitoring, automotive, avionics, and household appliances. Concurrently, the microelectronics and microfabrication technology have provided us with the means of producing mechanical microsensors characterized by high sensitivity, small size, integrated electronics, on board calibration, and low cost. Here we report a new kind of mechanical sensors based on the quantum transport process of electrons in the closely spaced nanoparticle films covering a flexible polymer sheet. The nanoparticle films were fabricated by gas phase depositing of preformed metal nanoparticles with a controlled coverage on the electrodes. To amplify the conductance of the nanoparticle array, we fabricated silver interdigital electrodes on polyethylene terephthalate(PET) by mask evaporation deposition. The gaps of the electrodes ranged from 3 to 30μm. Metal nanoparticles were generated from a magnetron plasma gas aggregation cluster source and deposited on the interdigital electrodes. Closely spaced nanoparticle arrays with different coverage could be gained through real-time monitoring the conductance. In the film coulomb blockade and quantum, tunneling/hopping dominate the electronic conduction mechanism. The basic principle of the mechanical sensors relies on the mechanical deformation of the fabricated devices which are translated into electrical signals. Several kinds of sensing devices have been explored. As a strain sensor, the device showed a high sensitivity as well as a very wide dynamic range. A gauge factor as large as 100 or more was demonstrated, which can be at least one order of magnitude higher than that of the conventional metal foil gauges or even better than that of the semiconductor-based gauges with a workable maximum applied strain beyond 3%. And the strain sensors have a workable maximum applied strain larger than 3%. They provide the potential to be a new generation of strain sensors with performance superior to that of the currently existing strain sensors including metallic strain gauges and semiconductor strain gauges. When integrated into a pressure gauge, the devices demonstrated the ability to measure tiny pressure change as small as 20Pa near the atmospheric pressure. Quantitative vibration measurements were realized on a free-standing cantilever structure fabricated with closely-spaced nanoparticle array sensing element. What is more, the mechanical sensor elements can be easily scaled down, which is feasible for MEMS and NEMS applications.

Keywords: gas phase deposition, mechanical sensors, metallic nanoparticle arrays, quantum conductance

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Authors: Hyeon Sop Baek

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This paper will investigate the Korean concept of han and suggest that the feeling of han is essentially inseparable from the central project of the Korean neo-Confucian philosophical tradition. Han is a complex sentiment, but one may characterize it as an internally directed complex of sentiments of frustration, sadness, and anger. In particular, this paper aims to demonstrate that the Korean neo-Confucian project's ultimate objective was to build a pluralistic world – where different people can coexist together in harmony and participate in building the ideal world. Nevertheless, the confrontation between the neo-Confucian idea – that every person has the intrinsic potential to be moral – and the bleakness of reality that made their objective virtually impossible to achieve led to the formation and development of the feeling of han. The paper will first examine the concept of han and what it entails and then investigate the core elements of Korean neo-Confucianism, examining the works of Korean neo-Confucians, including Toegye, Yulgok, and Jeong Dojeon. Furthermore, the concept of plurality will be drawn from the political theory of Hannah Arendt. While the Arendtian and Korean neo-Confucian philosophies are ultimately different, this paper will contend that the two philosophies' broader aims share many resonating points. Specifically, within both philosophies, the human plurality – that all humans are equal but not the same – underlies the foundation of an ideal political realm. From there, an argument that the difficulty faced by the neo-Confucians in Korea in constructing a polity based on the ideal of respect and human moral capacity ultimately contributed to the emergence of the sentiment han will be presented. In conclusion, this paper will demonstrate that the ultimate objectives of Korean Confucianism lie in closing the gap between the ideal and reality in moral cultivation as well as its political project of building an ideal, pluralistic world, and han emerges from the realization of the difficulty of achieving that goal. Finally, this paper will contest that han needs not be perceived negatively, and han can be a driving force for political participation in the contemporary democratic, pluralistic society.

Keywords: Korea, Confucianism, neo-Confucianism, philosophy, han, Korean philosophy

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Authors: Ingrid Snustad, Asmund Ervik, Anders Austegard, Amy Brunsvold, Jianying He, Zhiliang Zhang

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CO₂ capture, transport and storage (CCS) is essential to mitigate global anthropogenic CO₂ emissions. To make CCS a widely implemented technology in, e.g. the power sector, the reduction of costs is crucial. For a large cost reduction, every part of the CCS chain must contribute. By increasing the heat transfer efficiency during liquefaction of CO₂, which is a necessary step, e.g. ship transportation, the costs associated with the process are reduced. Heat transfer rates during dropwise condensation are up to one order of magnitude higher than during filmwise condensation. Dropwise condensation usually occurs on a non-wetting surface (Superlyophobic surface). The vapour condenses in discrete droplets, and the non-wetting nature of the surface reduces the adhesion forces and results in shedding of condensed droplets. This, again, results in fresh nucleation sites for further droplet condensation, effectively increasing the liquefaction efficiency. In addition, the droplets in themselves have a smaller heat transfer resistance than a liquid film, resulting in increased heat transfer rates from vapour to solid. Surface tension is a crucial parameter for dropwise condensation, due to its impact on the solid-liquid contact angle. A low surface tension usually results in a low contact angle, and again to spreading of the condensed liquid on the surface. CO₂ has very low surface tension compared to water. However, at relevant temperatures and pressures for CO₂ condensation, the surface tension is comparable to organic compounds such as pentane, a dropwise condensation of CO₂ is a completely new field of research. Therefore, knowledge of several important parameters such as contact angle and drop size distribution must be gained in order to understand the nature of the condensation. A new setup has been built to measure these relevant parameters. The main parts of the experimental setup is a pressure chamber in which the condensation occurs, and a high- speed camera. The process of CO₂ condensation is visually monitored, and one can determine the contact angle, contact angle hysteresis and hence, the surface adhesion of the liquid. CO₂ condensation on different surfaces can be analysed, e.g. copper, aluminium and stainless steel. The experimental setup is built for accurate measurements of the temperature difference between the surface and the condensing vapour and accurate pressure measurements in the vapour. The temperature will be measured directly underneath the condensing surface. The next step of the project will be to fabricate nanostructured surfaces for inducing superlyophobicity. Roughness is a key feature to achieve contact angles above 150° (limit for superlyophobicity) and controlled, and periodical roughness on the nanoscale is beneficial. Surfaces that are non- wetting towards organic non-polar liquids are candidates surface structures for dropwise condensation of CO₂.

Keywords: CCS, dropwise condensation, low surface tension liquid, superlyophobic surfaces

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