Search results for: chemical elements

Authors: Md. Belal Uudin Rabbi, Sakib Al Montasir, Saifur Rahman, Niger Nahid, Esmail Hossain Emon

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The practice of radiation shielding protects against the detrimental effects of ionizing radiation. Radiation shielding depletes radiation by inserting a shield of absorbing material between any radioactive source. It is a primary concern when building several industrial fields, so using potent (high activity) radioisotopes in food preservation, cancer treatment, and particle accelerator facilities is significant. Radiation shielding is essential for radiation-emitting equipment users to reduce or mitigate radiation damage. Polymer composites (especially epoxy based) with high atomic number fillers can replace toxic Lead in ionizing radiation shielding applications because of their excellent mechanical properties, superior solvent and chemical resistance, good dimensional stability, adhesive, and less toxic. Due to being lightweight, good neutron shielding ability in almost the same order as concrete, epoxy-based radiation shielding can be the next big thing. Micro and nano-particles for the epoxy resin increase the epoxy matrix's radiation shielding property. Shielding is required to protect users of such facilities from ionizing radiation as recently, and considerable attention has been paid to polymeric composites as a radiation shielding material. This research will examine the radiation shielding performance of epoxy-based nano-WO3 reinforced composites, exploring the performance of epoxy-based nano-WO3 reinforced composites. The samples will be prepared using the direct pouring method to block radiation. The practice of radiation shielding protects against the detrimental effects of ionizing radiation.

Keywords: radiation shielding materials, ionizing radiation, epoxy resin, Tungsten oxide, polymer composites

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Authors: Wilman Septina, Rajiv R. Prabhakar, Thomas Moehl, David Tilley

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Cupric oxide (CuO) is a promising absorber material for the fabrication of scalable, low cost solar energy conversion devices, due to the high abundance and low toxicity of copper. It is a p-type semiconductor with a band gap of around 1.5 eV, absorbing a significant portion of the solar spectrum. One of the main challenges in using CuO as solar absorber in an aqueous system is its tendency towards photocorrosion, generating Cu2O and metallic Cu. Although there have been several reports of CuO as a photocathode for hydrogen production, it is unclear how much of the observed current actually corresponds to H2 evolution, as the inevitability of photocorrosion is usually not addressed. In this research, we investigated the effect of the deposition of overlayers onto CuO thin films for the purpose of enhancing its photostability as well as performance for water splitting applications. CuO thin film was fabricated by galvanic electrodeposition of metallic copper onto gold-coated FTO substrates, followed by annealing in air at 600 °C. Photoelectrochemical measurement of the bare CuO film using 1 M phosphate buffer (pH 6.9) under simulated AM 1.5 sunlight showed a current density of ca. 1.5 mA cm-2 (at 0.4 VRHE), which photocorroded to Cu metal upon prolonged illumination. This photocorrosion could be suppressed by deposition of 50 nm-thick TiO2, deposited by atomic layer deposition. In addition, we found that insertion of an n-type CdS layer, deposited by chemical bath deposition, between the CuO and TiO2 layers was able to enhance significantly the photocurrent compared to without the CdS layer. A photocurrent of over 2 mA cm-2 (at 0 VRHE) was observed using the photocathode stack FTO/Au/CuO/CdS/TiO2/Pt. Structural, electrochemical, and photostability characterizations of the photocathode as well as results on various overlayers will be presented.

Keywords: CuO, hydrogen, photoelectrochemical, photostability, water splitting

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Authors: Zhongzhong Zeng, Zichen Liang

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In recent years, Beijing courtyards have been facing the problem of renewal and renovation, and the residents are faced with the problems of small house areas, large household sizes, old and dangerous houses, etc. Among the many renovation methods, the authors note two more common practices of using the front porch to expand the floor area and adding a loft. Residents and architects, however, did not give the ventilation performance of the significant interior consideration before beginning the remodeling. The aim of this article is to explore the good or negative impacts of both front porch and loft structures on the manner of interior ventilation in the courtyard. Ventilation, in turn, is crucial to the indoor environmental quality of a home. The major method utilized in this study is the comparative analysis method, in which the authors create four alternative house models with or without a front porch and an attic as two variables and examine internal ventilation using the CFD(Computational Fluid Dynamics) technique. The authors compare the indoor ventilation of four different architectural models with or without front porches and lofts as two variables. The results obtained from the analysis of the sectional airflow and the plane 1.5m height cloud are the existence of the loft, to a certain extent, disrupts the airflow organization of the building and makes the rear wall high windows of the building less effective. Occupying the front porch to become the area of the house has no significant effect on ventilation, but try not to occupy the front porch and add the loft at the same time in the building renovation. The findings of this study led to the following recommendations: strive to preserve the courtyard building's original architectural design and make adjustments to only the inappropriate elements or constructions. The ventilation in the loft portion is inadequate, and the inhabitants typically use the loft as a living area. This may lead to the building relying more on air conditioning in the summer, which would raise energy demand. The front porch serves as a transition place as well as a source of shade, weather protection, and inside ventilation. In conclusion, the examination of interior environments in upcoming studies should concentrate on cross-disciplinary, multi-angle, and multi-level research topics.

Keywords: Beijing courtyard renewal, CFD, indoor environment, ventilation analysis

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Authors: Parul Goel, Jyeshtharaj B. Joshi, Arun K. Nayak

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Nucleate boiling is characterized by the nucleation, growth and departure of the tiny individual vapor bubbles that originate in the cavities or imperfections present in the heating surface. It finds a wide range of applications, e.g. in heat exchangers or steam generators, core cooling in power reactors or rockets, cooling of electronic circuits, owing to its highly efficient transfer of large amount of heat flux over small temperature differences. Hence, it is important to be able to predict the rate of heat transfer and the safety limit heat flux (critical heat flux, heat flux higher than this can lead to damage of the heating surface) applicable for any given system. A large number of experimental and analytical works exist in the literature, and are based on the idea that the knowledge of the bubble dynamics on the microscopic scale can lead to the understanding of the full picture of the boiling heat transfer. However, the existing data in the literature are scattered over various sets of conditions and often in disagreement with each other. The correlations obtained from such data are also limited to the range of conditions they were established for and no single correlation is applicable over a wide range of parameters. More recently, a number of researchers have been trying to remove empiricism in the heat transfer models to arrive at more phenomenological models using extensive numerical simulations; these models require state-of-the-art experimental data for a wide range of conditions, first for input and later, for their validation. With this idea in mind, experiments with sub-cooled and saturated demineralized water have been carried out under atmospheric pressure to study the bubble dynamics- growth rate, departure size and frequencies for nucleate pool boiling. A number of heating elements have been used to study the dependence of vapor bubble dynamics on the heater surface finish and heater geometry along with the experimental conditions like the degree of sub-cooling, super heat and the heat flux. An attempt has been made to compare the data obtained with the existing data and the correlations in the literature to generate an exhaustive database for the pool boiling conditions.

Keywords: experiment, boiling, bubbles, bubble dynamics, pool boiling

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Authors: Bhawna Shivan

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Indian monuments have been spoken of as for variety, extent, completeness and beauty unsurpassed perhaps unequaled in world. India’s monumental heritage is a part and parcel of India today. The underlying issue with the monumental heritage in contemporary times is that these monuments suffered many times with various degrees of threats/ pressures which hampered their beauty. In the current situation, the urbanization policies for sustainable development and tourism management pay no attention to the basic point of conservation and protection of these cultural heritages rather they focus more on profit earned from these sites. Many times rich heritage is found balancing between conflicting pressures of conservation of heritage elements with sustainability and local economic development. There is a need of a new attitude to India’s independent and democratic ideology. The paper will enquire about the historical perspective by analyzing and understanding the importance of Mughal Architecture while focusing on Humayun Tomb while assessing the value and sentiment people attach to these monuments. It will also put the focus on the future of these monuments in the era of globalization and urbanization. The role of public and private authorities for conservation and sustainable development of these monuments. As well as assessing other facilities like toilets, parking, eatery joint, Museum with Display of structural representation and display of books, and a mobile shop. The research will be helpful in assessing the importance of heritage buildings whether they are a tool of enhancing ‘Tourism Industry’ for Central and State Government or really there is still some future of these monuments. Can we still consider these heritage sites as the integral part of our society in this urbanized world? The study will also analyze the attitude of the central and state government towards a building when it declared as a ‘World Heritage Site’. The study will also examine how the Youth and other aged generations append their sentimental values towards them, say (what is their purpose of coming to a heritage site, what makes them coming here, how they view this particular monument) Apart from this, probing the factors such as rapid growth of cities and its population, increasing value of urban land and effect of globalization on urban growth pattern that are capable of producing a variety of threats and pressures on any monument for instance Humayun Tomb.

Keywords: globalization, monuments, tourism, urban heritage

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Authors: Tatyana T. Tabakova, Elitsa N. Kolentsova, Dimitar Y. Dimitrov, Krasimir I. Ivanov, Yordanka G. Karakirova, Petya Cv. Petrova, Georgi V. Avdeev

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The catalytic oxidation of CO and volatile organic compounds (VOCs) is considered as one of the most efficient ways to reduce harmful emissions from various chemical industries. The effectiveness of gold-based catalysts for many reactions of environmental significance was proven during the past three decades. The aim of this work was to combine the favorable features of Au and Cu-Ce mixed oxides in the design of new catalytic materials of improved efficiency and economic viability for removal of air pollutants in waste gases from formaldehyde production. Supported oxides of copper and cerium with Cu: Ce molar ratio 2:1 and 1:5 were prepared by wet impregnation of g-alumina. Gold (2 wt.%) catalysts were synthesized by a deposition-precipitation method. Catalysts characterization was carried out by texture measurements, powder X-ray diffraction, temperature programmed reduction and electron paramagnetic resonance spectroscopy. The catalytic activity in the oxidation of CO, CH₃OH and (CH₃)₂O was measured using continuous flow equipment with fixed bed reactor. Both Cu-Ce/alumina samples demonstrated similar catalytic behavior. The addition of gold caused significant enhancement of CO and methanol oxidation activity (100 % degree of CO and CH₃OH conversion at about 60 and 140 ^oC, respectively). The composition of Cu-Ce mixed oxides affected the performance of gold-based samples considerably. Gold catalyst on Cu-Ce/γ-Al₂O₃ 1:5 exhibited higher activity for CO and CH₃OH oxidation in comparison with Au on Cu-Ce/γ-Al₂O₃ 2:1. The better performance of Au/Cu-Ce 1:5 was related to the availability of highly dispersed gold particles and copper oxide clusters in close contact with ceria.

Keywords: CO and VOCs oxidation, copper oxide, Ceria, gold catalysts

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Authors: Niloofar Bahramian, Mohammad Atai, Mohammad Reza Naimi-Jamal

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Rule of mixtures is the simple analytical model is used to predict various properties of composites before design. The aim of this study was to demonstrate the benefits and limitations of the Rule-of-Mixtures (ROM) for predicting bending modulus of a continuous and unidirectional fiber reinforced composites using in dental applications. The Composites were fabricated from light curing resin (with and without silica nanoparticles) and modified and non-modified fibers. Composite samples were divided into eight groups with ten specimens for each group. The bending modulus (flexural modulus) of samples was determined from the slope of the initial linear region of stress-strain curve on 2mm×2mm×25mm specimens with different designs: fibers corona treatment time (0s, 5s, 7s), fibers silane treatment (0%wt, 2%wt), fibers volume fraction (41%, 33%, 25%) and nanoparticles incorporation in resin (0%wt, 10%wt, 15%wt). To study the fiber and matrix interface after fracture, single edge notch beam (SENB) method and scanning electron microscope (SEM) were used. SEM also was used to show the nanoparticles dispersion in resin. Experimental results of bending modulus for composites made of both physical (corona) and chemical (silane) treated fibers were in reasonable agreement with linear ROM estimates, but untreated fibers or non-optimized treated fibers and poor nanoparticles dispersion did not correlate as well with ROM results. This study shows that the ROM is useful to predict the mechanical behavior of unidirectional dental composites but fiber-resin interface and quality of nanoparticles dispersion play important role in ROM accurate predictions.

Keywords: bending modulus, fiber reinforced composite, fiber treatment, rule-of-mixtures

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Authors: Lian Zeng

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Double-Spear 1-H2-1 (DS1-H2-1) is an oncolytic virus and an innovative biological drug candidate. The chemical composition of the drug product is a live attenuated West Nile virus (WNV) containing the human T cell costimulator (CD86) gene. After intratumoral injection, the virus can rapidly self-replicate in the injected site and lyse/kill the tumor by repeated infection among tumor cells. We also established xenograft tumor models in mice to evaluate the drug candidate's efficacy on those tumors. The results from preclinical studies on transplanted tumors in immunodeficient mice showed that DS1-H2-1 had significant oncolytic effects on human-origin cancers: it completely (100%) shrieked human glioma; limited human neuroblastoma growth reached as high as 95% growth inhibition rate (%TGITW). The safety data of preclinical animal experiments confirmed that DS1-H2-1 is safe as a biological drug for clinical use. In the preclinical drug efficacy experiment, virus-drug administration with different doses did not show abnormal signs and disease symptoms in more than 300 tested mice, and no side effects or death occurred through various administration routes. Intravenous administration did not cause acute infectious disease or other side effects. However, the replication capacity of the virus in tumor tissue via intravenous administration is only 1% of that of direct intratumoral administration. The direct intratumoral administration of DS1-H2-1 had a higher rate of viral replication. Therefore, choosing direct intratumoral injection can ensure both efficacy and safety.

Keywords: oncolytic virus, WNV-CD86, immunotherapy drugs, glioma, neuroblastoma

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Authors: Tiffany Karalis Noel

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The purpose of this study was to examine the factors attributed to the self-efficacy of beginning secondary content area teachers as they moved through their student teaching experiences. This study used a narrative inquiry methodology to understand the variables attributed to teacher self-efficacy among a group of secondary content area teacher candidates. The primary purpose of using a narrative inquiry methodology was to share the stories of content area teacher candidates’ student teaching experiences. Focused research questions included: (1) To what extent does teacher education preparation affect the self-efficacy of beginning content area teachers? (2) Which recurrent elements of teacher education affect the self-efficacy of beginning teachers, regardless of content area? (3) How do the findings from research questions 1 and 2 inform teacher educators? The findings of this study suggest that teacher education preparation affects the self-efficacy of beginning secondary teacher candidates across the content areas; accordingly, the findings of this study provide insight for teacher educators to consider the areas where teacher education programs are failing to provide adequate preparation. These teacher candidates emphasized the value of adequate preparation throughout their teacher education programs to help inform their student teaching experiences. In order to feel effective and successful as beginning teachers, these teacher candidates required additional opportunities to apply the practical application of their teaching skills prior to the student teaching experience, the incorporation of classroom management strategy coursework into their curriculum, and opportunities to explore the extensive demands of the teaching profession ranging from time management to dealing with difficult parents, to name a few referenced examples. The teacher candidates experienced feelings of self-doubt related to their effectiveness as teachers when they were unable to employ successful classroom management strategies, pedagogical techniques, or even feel confidence in navigating challenging conversations with students, parents, and/or administrators. In order to help future teacher candidates and beginning teachers in general overcome these barriers, additional coursework, fieldwork, and practical application experiences should be provided in teacher education programs to help boost the self-efficacy of student teachers.

Keywords: self-efficacy, teacher efficacy, secondary preservice teacher education, teacher candidacy, student teaching

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Authors: Mohadese Hashemi, Elham Akhoundi Kharanaghi, Fatemeh Haghiralsadat, Mojgan Yazdani, Omid Javani, Mahboobe Sharafodini, Davood Rajabi

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Niosomes are non-ionic surfactant vesicles in aqueous media resulting in closed bilayer structures that can be used as carriers of hydrophilic and hydrophobic compounds. The use of niosomes for encapsulation of essential oils (EOs) is an attractive new approach to overcome their physicochemical stability concerns include sensibility to oxygen, light, temperature, and volatility, and their reduced bioavailability which is due to low solubility in water. EOs are unstable and fragile volatile compounds which have strong interest in pharmaceutical due to their medicinal properties such as antiviral, anti-inflammatory, antifungal, and antioxidant activities without side effects. Trachyspermum copticum (ajwain) is an annual aromatic plant with important medicinal properties that grows widely around Mediterranean region and south-west Asian countries. The major components of the ajwain oil were reported as thymol, γ-terpinene, p-cymene, and carvacrol which provide antimicrobial and antioxidant activity. The aim of this work was to formulate ajwain essential oil-loaded niosomes to improve water solubility of natural product and evaluate its physico-chemical features and stability. Ajwain oil was obtained through steam distillation using a clevenger-type apparatus and GC/MS was applied to identify the main components of the essential oil. Niosomes were prepared by using thin film hydration method and nanoparticles were characterized for particle size, dispersity index, zeta potential, encapsulation efficiency, in vitro release, and morphology.

Keywords: trachyspermum copticum, ajwain, niosome, essential oil, encapsulation

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Authors: B. Rusyidi

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Since 2009, the Indonesian Ministry of Social Affairs has been implementing Program Kesejahteraan Sosial Anak (PKSA) (Child Welfare Program) a conditional cash transfer program that targets neglected children, children with disabilities, street children, children in conflict with the law, and children in need of special protection, all from poor households. PKSA integrates three elements: Transfer of cash, care and social services through social workers, and institutional childcare assistance. This qualitative study analyzed the roles and the challenges of social workers in implementing PKSA and lays out recommendations to inform policy changes. Data were collected in late 2014 from national and local government and non-government child welfare agencies, social workers, and childcare institution representatives through interviews and Focused Group Discussions (FGDs). Field work took place in six districts in the provinces of Jakarta, Central Java and South Sulawesi. The study found that the social workers’ role was significant in facilitating cash transfer, providing education and guidance, and linking children and families to basic social services. This improved utilization of basic social services enhanced children and families’ behaviors and contributed to the well being of the children. However, only a small number of childcare institutions have social workers, leaving many children and families without care and social service linkages, depriving them of rehabilitative components to help them regain their social functions. Some social workers reported their struggles with heavy workloads, lack of professional competencies and training, limited job security, and inadequate professional acknowledgment from other professions. Parts of those challenges were due to the centralized nature of the program and the lack of shared vision and commitment about the child protection system among related government agencies both at the national and local levels. The study highlights the necessity to implement an integrated child protection system, decentralize the PKSA program, and increase the number, competence, case management, and management and monitoring of social workers. The most recent progress of the program and its impacts on social workers are also discussed.

Keywords: child protection, conditional cash transfer, program decentralization, social worker, working conditions

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Authors: Suguru Miyauchi, Toshiyuki Hayase

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Biological membranes have selective permeability, and the capsules or cells enclosed by the membrane show the deformation by the osmotic flow. This mass transport phenomenon is observed everywhere in a living body. For the understanding of the mass transfer in a body, it is necessary to consider the mass transfer phenomenon across the membrane as well as the deformation of the membrane by a flow. To our knowledge, in the numerical analysis, the method for mass transfer across the moving membrane has not been established due to the difficulty of the treating of the mass flux permeating through the moving membrane with selective permeability. In the existing methods for the mass transfer across the membrane, the approximate delta function is used to communicate the quantities on the interface. The methods can reproduce the permeation of the solute, but cannot reproduce the non-permeation. Moreover, the computational accuracy decreases with decreasing of the permeable coefficient of the membrane. This study aims to develop the numerical method capable of treating three-dimensional problems of mass transfer across the moving flexible membrane. One of the authors developed the numerical method with high accuracy based on the finite element method. This method can capture the discontinuity on the membrane sharply due to the consideration of the jumps in concentration and concentration gradient in the finite element discretization. The formulation of the method takes into account the membrane movement, and both permeable and non-permeable membranes can be treated. However, searching the cross points of the membrane and fluid element boundaries and splitting the fluid element into sub-elements are needed for the numerical integral. Therefore, cumbersome operation is required for a three-dimensional problem. In this paper, we proposed an improved method to avoid the search and split operations, and confirmed its effectiveness. The membrane shape was treated implicitly by introducing the level set function. As the construction of the level set function, the membrane shape in one fluid element was expressed by the shape function of the finite element method. By the numerical experiment, it was found that the shape function with third order appropriately reproduces the membrane shapes. The same level of accuracy compared with the previous method using search and split operations was achieved by using a number of sampling points of the numerical integral. The effectiveness of the method was confirmed by solving several model problems.

Keywords: finite element method, level set method, mass transfer, membrane permeability

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Authors: Nho-Eul Song, Sang-Ho Baik

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Fermentation characteristics of black raspberry vinegar by using static cultures without any additives were has been investigated to establish of vinegar manufacturing conditions and improve the quality of vinegar by optimization the vinegar manufacturing process. The two vinegar manufacturing conditions were prepared; one-step fermentation condition only using mother vinegar that prepared naturally occurring black raspberry vinegar without starter yeast for alcohol fermentation (traditional method) and two-step fermentation condition using commercial wine yeast and mother vinegar for acetic acid fermentation. Approximately 12% ethanol was produced after 35 days fermentation with log 7.6 CFU/mL of yeast population in one-step fermentation, resulting sugar reduction from 14 to 6oBrix whereas in two-step fermentation, ethanol concentration was reached up to 8% after 27 days with continuous increasing yeast until log 7.0 CFU/mL. In addition, yeast and ethanol were decreased after day 60 accompanied with proliferation of acetic acid bacteria (log 5.8 CFU/mL) and titratable acidity; 4.4% in traditional method and 6% in two-step fermentation method. DGGE analysis showed that S. cerevisiae was detected until 77 days of traditional fermentation and gradually changed to AAB, Acetobacter pasteurianus, as dominant species and Komagataeibacter xylinus at the end of the fermentation. However, S. cerevisiae and A. pasteurianus was dominant in two-step fermentation process. The prepared two-step fermentation showed enhanced total polyphenol and flavonoid content significantly resulting in higher radical scavenging activity. Our studies firstly revealed the microbial community change with chemical change and demonstrated a suitable fermentation system for black raspberry vinegar by the static surface method.

Keywords: bacteria, black raspberry, vinegar fermentation, yeast

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Authors: Indira Sinha

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According to the Oxford Advanced Learner's English Dictionary of Current English, environment is the complex of physical, chemical and biotic factors that act upon an organism or an ecological community and ultimately determines its form and survival. It is defined as conditions and circumstances which are affecting people's lives. The meaning of environmental degradation is the degradation of the environment through depletion of resources such as air, water and soil and the destruction of ecosystems and extinction of wildlife. Globalization is a significant feature of recent world history. The aim of this phenomenon is to integrate societies, economies and cultures through a common link of trading policies, technology and communication. Undoubtedly it has opened up the world economy at a very high speed but at the same time it has an adverse impact on the environment. The purpose of the present study is to investigate the impact of globalization on the environmental conditions. An overview of what the forces of globalization have in store for the environment with constructing large number of industries and destroying large forests lands will be given in this paper. The forces of globalization have created many serious environmental problems like high temperature, extinction of many species of plant and animal and outlet of poisonous chemicals from industries. The revelation of this study is that in case of developing economics these problems are more critical. In developing countries like India many factories are built with less environmental regulations, while developed economies maintain positive environmental practices. The present study is a micro level study which aims to employ a combination of theoretical, descriptive, empirical and analytical approach in addition to the time tested case method.

Keywords: globalization, trade policies, environmental degradation, developing economies, large industries

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Authors: Ikpesu, Thomas Ohwofasa, Babtunde Ilesanmi

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The effects of anthropogenic activities on fish and fisheries products in Niger Delta water bodies were investigated. The rivers were selected based on their close proximity to contaminants and dredging activities. Three stations were chosen per river. The stations chosen to depicting downstream and upstream stations were visited and samples collected on monthly basis. The down streams stations are the polluted and heavily dredged sites, where the upstream station is far, without any evidence of pollution or human activities. During these periods, the fishes of the same species were collected and analyzed for morphological and physiological changes, after which they were returned back to the rivers. The physico-chemicals parameters of these stations were also taken. Morphological changes such as skin ulcerations and other lesions, as well as fungi infections were observed in the down streams fishes. The fish in up streams look healthier and bigger (though the age could not be affirmed) than the downstream fishes. The physico-chemical parameters between the up streams and down streams stations vary significantly (p < 0.01). These anthropogenic effects must have interfere with the normal migration pattern of these fishes, because there were changes in the composition of population and species diversity in the samples sites, with the upstream having true species diversity. The release of pollutants into the water in the Niger Delta areas may triggers off naturally occurring bio toxicity cycles and other fish poisoning. There is risk of biomagnifications of these poisons along the tropic level. This makes the normally valuable food resource dangerous for human consumption and thereby instances of human death caused by such poisoning.

Keywords: anthropogenic, dredging, fisheries, niger delta, pollution, rivers

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Authors: Spandana Ramisetty, Mandan Chidambaram, Ramesh Bhujade

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Algal biomass is not only a potential source for biocrude but also for high value chemicals like carotenoids, fatty acids, proteins, polysaccharides, vitamins etc. Astaxanthin is one such high value vital carotenoid which has extensive applications in pharmaceutical, aquaculture, poultry and cosmetic industries and expanding as dietary supplement to humans. Green microalgae Haematococcus pluvialis is identified as the richest natural source of astaxanthin and is the key source of commercial astaxanthin. Several extraction processes from wet and dry Haematococcus pluvialis biomass have been explored by researchers. Extraction with supercritical CO₂ and various physical disruption techniques like mortar and pestle, homogenization, ultrasonication and ball mill from dried algae are widely used extraction methods. However, these processes require energy intensive drying of biomass that escalates overall costs notably. From the process economics perspective, it is vital to utilize wet processing technology in order to eliminate drying costs. Hydrothermal liquefaction (HTL) is a thermo-chemical conversion process that converts wet biomass containing over 80% water to bio-products under high temperature and high pressure conditions. Astaxanthin is a lipid soluble pigment and is usually extracted along with lipid component. Mild HTL at 200°C and 60 bar has been demonstrated by researchers in a microfluidic platform achieving near complete extraction of astaxanthin from wet biomass. There is very limited work done in this field. An integrated approach of sequential HTL offers cost-effective option to extract astaxanthin/lipid from wet algal biomass without drying algae and also recovering water, minerals and nutrients. This paper reviews past work and evaluates the astaxanthin extraction processes with focus on hydrothermal extraction.

Keywords: astaxanthin, extraction, high value chemicals, hydrothermal liquefaction

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Authors: María D. Groppa, Andrea Trentini, Myriam Zawoznik, Roxana Bigi, Carlos Nadra, Patricia L. Marconi

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In the present work, a remediation bioprocess based on the use of a local isolate of the microalgae Chlorella vulgaris immobilized in alginate beads is proposed. This process was shown to be effective for the reduction of several chemical and microbial contaminants present in Cildáñez stream, a water course that is part of the Matanza-Riachuelo Basin (Buenos Aires, Argentina). The bioprocess, involving the culture of the microalga in autotrophic conditions in a stirred-tank bioreactor supplied with a marine propeller for 6 days, allowed a significant reduction of Escherichia coli and total coliform numbers (over 95%), as well as of ammoniacal nitrogen (96%), nitrates (86%), nitrites (98%), and total phosphorus (53%) contents. Pb content was also significantly diminished after the bioprocess (95%). Standardized cytotoxicity tests using Allium cepa seeds and Cildáñez water pre- and post-remediation were also performed. Germination rate and mitotic index of onion seeds imbibed in Cildáñez water subjected to the bioprocess was similar to that observed in seeds imbibed in distilled water and significantly superior to that registered when untreated Cildáñez water was used for imbibition. Our results demonstrate the potential of this simple and cost-effective technology to remove urban-water contaminants, offering as an additional advantage the possibility of an easy biomass recovery, which may become a source of alternative energy.

Keywords: bioreactor, bioremediation, Chlorella vulgaris, Matanza-Riachuelo Basin, microalgae

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Authors: Toshikee Yadav, Deepti Tikariha, Jyotsna Lakra, Kallol K. Ghosh

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Polycyclic aromatic hydrocarbons (PAHs) are potent atmospheric pollutants that consist of two or more benzene rings. PAHs have low solubility in water. Their slow dissolution can contaminate large amounts of ground water for long period. They are hydrophobic, non-polar and neutral in nature and are known to have potential mutagenic or carcinogenic activity. In current scenario their removal from the environment, water and soil is still a great challenge and scientists worldwide are engaged to invent and design novel separation technology and decontaminating systems. Various physical, chemical, biological and their combined technologies have been applied to remediate organic-contaminated soils and groundwater. Surfactants play a vital role in the solubilization of these hydrophobic organic compounds. In the present investigation Solubilization capabilities of structurally different gemini surfactants i.e. butanediyl-1,4-bis(dimethyldodecylammonium bromide) (C12-4-C12,2Br−), 2-butanol-1,4-bis (dimethyldodecylammonium bromide) (C12-4(OH)-C12,2Br−), 2,3-butanediol-1,4-bis (dimethyldodecylammonium bromide) (C12-4(OH)2-C12,2Br−) for three polycyclic aromatic hydrocarbons (PAHs); phenanthrene (Phe),fluorene (Fluo) and acenaphthene (Ace) have been studied spectrophotometrically at 300 K. The result showed that the solubility of PAHs increases linearly with increasing surfactant concentration, as an implication of association between the PAHs and micelles. Molar solubilization ratio (MSR), micelle–water partition coefficient (Km) and Gibb's free energy of solubilization (ΔG°s) for PAHs have been determined in aqueous medium. (C12-4(OH)2-C12,2Br−) shows the higher solubilization for all PAHs. Findings of the present investigation may be useful to understand the role of appropriate surfactant system for the solubilization of toxic hydrophobic organic compounds.

Keywords: gemini surfactant, molar solubilization ratio, polycyclic aromatic hydrocarbon, solubilization

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Authors: Sayed Ali Garossi, Azar Heidarizadi, Shahla Mohammad Ganji

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Context: Colorectal cancer is the second type of cancer-related mortality globally. Expression of cas8 (caspase 8) is closely connected to growth and metastasis of colorectal cancer.Cas8/Rip1 plays a vital role in the apoptosis pathway and resistance to chemotherapy. The aim of the present study is to investigate the pattern of gene expression in colorectal cancer and compare the differences using Real-Time PCR to find a potential biomarker candidate for colorectal cancer. Methodology: This study conducted real-time PCR to evaluate gene expression of Cas8 in colorectal cancer patients. The gene-specific primer sequences exon–exon junction was designed by OLIGO7 software for the expression of the gene under investigation. Forty-six patient samples without any chemotherapy were selected, including tumoral tissue and adjacent normal tissue samples. The age of the patients was 50 and the size of the tumors was 5.5 cm. The categories were before and after age 50. Findings: Here, we found that Caspase 8 was overexpressed in CRC tissues compared to corresponding adjacent colon tissues (Cas8: 5.2 vs. 1 ratio); high expression of Cas8 was associated with poor overall survival and independent risk factors for the prognosis of CRC patients. Conclusion: In conclusion, our study pioneered the reporting of high Casp8 expression as a predictor of poor prognosis and chemical resistance in CRC patients.Cas8 overexpression suppressed Cas 8 / Rip1-dependent apoptosis and activated the proliferation of tumor cells by activating necroptosis. The necroptosis pathway has also emerged as a new approach to anti-tumor in cancer treatment.

Keywords: Cas8, necroptosis, apoptosis, Real-Time PCR

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Authors: Yemane Kahsay Berhe

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The multipurpose cactus pear plant with great potential as a source of food and livestock feed faced a threat from Dactylopius spp in different countries. Specifically, D. coccus is an important pest damaging significant areas in Tigray-Ethiopia. Using pest-resistant cultivars is an important element of an integrated pest management strategy, and studying the mechanisms of resistance is vital. It can be chemical or physical, such as oxalate crystals and other cladode characteristics. Cladode features of six cultivars (three O. ficus-indica, two O. cochenillifera, and one O. robusta) were examined for resistance to D. coccus in a completely randomized design (CRD) with three replications. ‘Rojo Pelón’ (O. ficus-indica), ‘Robusta’ (O. robusta), and ‘Bioplástico’ (O. cochinillifera) are resistant cultivars; and ‘Atlixco’ and ‘Chicomostoc’ (O. ficus-indica) and ‘Nopalea’ (O. cochinillifera) are susceptible. Cultivars showed a significant difference in cladode weight in g, cladode length, cladode width, and cladode thickness in cm, where cladode thickness was higher in ‘Rojo Pelón’ followed by ‘Robusta’. Calcium oxalates number per mm was higher in ‘Bioplástico’ (20.7+2.08) followed by ‘Robusta’ (18.9+2.31) and ‘Rojo Pelón’ (15.9+0.34); and similarly, epidermis thickness found higher in ‘Bioplástico’ (0.21+0.032) and ‘Robusta’ (0.19+0.014), but similar with ‘Rojo Pelón’ (0.18+0.026). However, cuticle thickness didn’t show a difference among cultivars. Cladode thickness, calcium oxalates number, and epidermis thickness had positive correlations with resistance. These results demonstrate that calcium oxalates number and epidermis thickness might positively affect D. coccus resistance in O. ficus-indica. This feeding-barring role and the insect-plant interaction need to be studied.

Keywords: cactus pear, resiatnce, druses, epidermis thickness

Procedia PDF Downloads 73

Authors: Q. Rzina, M. Lahrouni, S. Rida, N. Saadaoui, Y. Almossaid, K. Oufdou, K. Fares

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Many organic solid wastes are produced in the world. Poultry manure (PM), municipal organic wastes (MOW) and sugar beet lime sludge (LS) are produced in large quantities in Morocco. The co-composting of these organic wastes was investigated. The recycling and the valorization of such wastes is environmentally and economically beneficial especially for PM which is known source of bacterial pathogens. The aerobic biodegradation process was carried out by using three windrows of variable compositions: C1 prepared without LS (only MOW were composted with PM), C2 prepared from MOW plus PM and10% LS; and the last one C3 from MOW plus PM and 20% LS. The main process physico-chemical parameters (temperature, pH, humidity and C/N) and microbiological populations (mesophilic and thermophilic flora, total coliform, fecal coliform, Streptococci, Staphylococcus aureus and mesophilic fungi) were monitored over three months to ascertain the compost maturity and to ensure the compost hygienic aspect. The final products were characterized by their relatively high organic matter content, and low C/N ratio of 10.6-10.9. The organic matter degradation was reached approximately 59% for C2 and C3. In addition, the monitoring of the microbial population showed that the produced composts are mature and hygienic. The agronomic valorization of the final composts was tested on radish plant with tree level of composts and poultry manure without composting. The primary results of field trial showed a growth of radish plant biomass and root development without any phytotoxicity detected which reflects the quality of the composts produced. As for poultry manure it allowed to have a better results than other composts because of its readily available nitrogen.

Keywords: compost, municipal organic wastes, poultry manure, radish crop, sugar beet lime sludge

Procedia PDF Downloads 312

Authors: Patrick Mueller, Alan Martin, Justin Stockwell, Robert Goldblatt

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Elevated concentrations of inorganic nitrogen (N) compounds (nitrate, nitrite, and ammonia) are a ubiquitous feature to mine-influenced drainages due to the leaching of blasting residues and use of cyanide in the milling of gold ores. For many mines, the management of N is a focus for environmental protection, therefore understanding the factors controlling the speciation and behavior of N is central to effective decision making. In this paper, the passive attenuation of ammonia and nitrite is described for three northern water bodies (two lakes and a tailings pond) influenced by mining activities. In two of the water bodies, inorganic N compounds originate from explosives residues in mine water and waste rock. The third water body is a decommissioned tailings impoundment, with N compounds largely originating from the breakdown of cyanide compounds used in the processing of gold ores. Empirical observations from water quality monitoring indicate nitrification (the oxidation of ammonia to nitrate) occurs in all three waterbodies, where enrichment of nitrate occurs commensurately with ammonia depletion. The N species conversions in these systems occurred more rapidly than chemical oxidation kinetics permit, indicating that microbial mediated conversion was occurring, despite the cool water temperatures. While nitrification of ammonia and nitrite to nitrate was the primary process, in all three waterbodies nitrite was consistently present at approximately 0.5 to 2.0 % of total N, even following ammonia depletion. The persistence of trace amounts of nitrite under these conditions suggests the co-occurrence denitrification processes in the water column and/or underlying substrates. The implications for N management in mine waters are discussed.

Keywords: explosives, mining, nitrification, water

Procedia PDF Downloads 319

Authors: Mina Rouhollahi, J. Boland

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Changes in cities’ heat balance due to rapid urbanization and the urban heat island (UHI) have increased energy demands for space cooling and have resulted in uncomfortable living conditions for urban residents. Climate resilience and comfortable living spaces can be addressed through well-designed urban development. The sustainable housing can be more effective in controlling high levels of urban heat. In Australia, to mitigate the effects of UHIs and summer heat waves, one solution to sustainable housing has been the trend to compact housing design and the construction of energy efficient dwellings. This paper analyses whether current housing configurations and orientations are effective in avoiding increased demands for air conditioning and having an energy efficient residential neighborhood. A significant amount of energy is consumed to ensure thermal comfort in houses. This paper reports on the modelling of heat transfer within the homes using the measurements of radiation, convection and conduction between exterior/interior wall surfaces and outdoor/indoor environment respectively. The simulation was tested on selected 7.5-star energy efficient houses constructed of typical material elements and insulation in Adelaide, Australia. The chosen design dwellings were analyzed in extremely hot weather through one year. The data were obtained via a thermal circuit to accurately model the fundamental heat transfer mechanisms on both boundaries of the house and through the multi-layered wall configurations. The formulation of the Lumped capacitance model was considered in discrete time steps by adopting a non-linear model method. The simulation results focused on the effects of orientation of the solar radiation on the dynamic thermal characteristics of the houses orientations. A high star rating did not necessarily coincide with a decrease in peak demands for cooling. A more effective approach to avoid increasing the demands for air conditioning and energy may be to integrate solar–climatic data to evaluate the performance of energy efficient houses.

Keywords: energy-efficient residential building, heat transfer, neighborhood orientation, solar–climatic data

Procedia PDF Downloads 133

Authors: Farzad Doostishoar, Abdolreza Hasanzadeh, Seyed Amin Ayatolahi Mousavi

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Introduction and Goals: Deuterium has different action from its isotopes hydrogen in chemical reactions and biochemical processes. It is not a significant difference in heavier atoms between the behavior of heavier isotope and the lighter One but for very lighter atoms it is significant . According to that most of the weight of all creatures body is water natural rate can be significant. In this article we want to study the effect of reduced deuterium on the fungus cell. If we saw the dependence of deuterium concentration of environment on the cells growth we can test this in invivo models too. Methods: First we measured deuterium concentration of the distillated water this analyze was operated by Arak’s heavy water company. Then the deuterium was diluted to ½ ¼ 1/8 1/16 by adding water free of deuterium for making media. In tree of samples the deuterium concentration was increased by adding D2O up to 10,50,100 times more concentrated. For candida albicans growth we used sabor medium and for aspergillus fomigatis growth we used sabor medium containing chloramphenicol. After culturing the funguses species we put the mediums for each species in the shaker incubator for 10 days in 25 centigrade. In different days and times the plates were studied morphologically and some microscopic characteristics were studied too. This experiments and cultures were repeated 3 times. Results: Statistical analyzes by paired-sample T test showed that aspergilus fomigatoos growth was decreased in concentration of 72 ppm( half deuterium concentration of negative control) significantly. In deuterium concentration reduction the growth reduce into the negative control significantly. The project results showed that candida albicans was sensitive to reduce and decrease of the deuterium in all concentrations.

Keywords: deuterium, cancer cell, growth, candida albicans

Procedia PDF Downloads 401

Authors: Ugur Fidan, Naim Karasekreter

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Healthy and clean water should not contain disease-causing micro-organisms and toxic chemicals and must contain the necessary minerals in a balanced manner. Today, water resources have a limited and strategic importance, necessitating the management of water reserves. Water tanks meet the water needs of people and should be regularly chlorinated to prevent waterborne diseases. For this purpose, automatic chlorination systems placed in water tanks for killing bacteria. However, the regular operation of automatic chlorination systems depends on refilling the chlorine tank when it is empty. For this reason, there is a need for a stock control system, in which chlorine levels are regularly monitored and supplied. It has become imperative to take urgent measures against epidemics caused by the fact that most of our country is not aware of the end of chlorine. The aim of this work is to rehabilitate existing water tanks and to provide a method for a modern water storage system in which chlorination is digitally monitored by turning the newly established water tanks into a closed system. A sensor network structure using GSM/GPRS communication infrastructure has been developed in the study. The system consists of two basic units: hardware and software. The hardware includes a chlorine level sensor, an RFID interlock system for authorized personnel entry into water tank, a motion sensor for animals and other elements, and a camera system to ensure process safety. It transmits the data from the hardware sensors to the host server software via the TCP/IP protocol. The main server software processes the incoming data through the security algorithm and informs the relevant unit responsible (Security forces, Chlorine supply unit, Public health, Local Administrator) by e-mail and SMS. Since the software is developed base on the web, authorized personnel are also able to monitor drinking water tank and report data on the internet. When the findings and user feedback obtained as a result of the study are evaluated, it is shown that closed drinking water tanks are built with GRP type material, and continuous monitoring in digital environment is vital for sustainable health water supply for people.

Keywords: wireless sensor networks (WSN), monitoring, chlorine, water tank, security

Procedia PDF Downloads 160

Authors: L. Mentar, O. Baka, M. R. Khelladi, A. Azizi

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Zinc oxide (ZnO), as a transparent semiconductor with a wide band gap of 3.4 eV and a large exciton binding energy of 60 meV at room temperature, is one of the most promising materials for a wide range of modern applications. With the development of film growth technologies and intense recent interest in nanotechnology, several varieties of ZnO nanostructured materials have been synthesized almost exclusively by thermal evaporation methods, particularly chemical vapor deposition (CVD), which generally require a high growth temperature above 550 °C. In contrast, wet chemistry techniques such as hydrothermal synthesis and electro-deposition are promising alternatives to synthesize ZnO nanostructures, especially at a significantly lower temperature (below 200°C). In this study, the electro-deposition method was used to produce zinc oxide (ZnO) nanostructures on fluorine-doped tin oxide (FTO)-coated conducting glass substrate from chloride bath. We present the influence of KCl concentrations on the electro-deposition process, morphological, structural and optical properties of ZnO nanostructures. The potentials of electro-deposition of ZnO were determined using the cyclic voltammetry. From the Mott-Schottky measurements, the flat-band potential and the donor density for the ZnO nanostructure are determined. Field emission scanning electron microscopy (FESEM) images showed different sizes and morphologies of the nanostructures which depends on the concentrations of Cl-. Very netted hexagonal grains are observed for the nanostructures deposited at 0.1M of KCl. X-ray diffraction (XRD) study confirms the Wurtzite phase of the ZnO nanostructures with a preferred oriented along (002) plane normal to the substrate surface. UV-Visible spectra showed a significant optical transmission (~80%), which decreased with low Cl-1 concentrations. The energy band gap values have been estimated to be between 3.52 and 3.80 eV.

Keywords: Cl-, electro-deposition, FESEM, Mott-Schottky, XRD, ZnO

Procedia PDF Downloads 289

Authors: Abdolreza Farhadian, Anh Phan, Zahra Taheri Rizi, Elaheh Sadeh

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The utilization of solidified gas technology based on hydrates exhibits considerable promise for carbon capture, storage, and natural gas transportation applications. The pivotal factor impeding the industrial implementation of hydrates lies in the need for efficient and non-foaming promoters. In this study, a biosurfactant with sulfonate, amide, and carboxyl groups (BS) was synthesized as a methane hydrate formation promoter, replicating the chemical characteristics of amino acids and sodium dodecyl sulfate (SDS). The synthesis of BS follows a simple, three-step process that is amenable to industrial scale production. The first two steps of the process are solvent-free, which helps reduce potential environmental impacts and makes scaling up more feasible. Additionally, the final step utilizes a water-isopropanol mixture, which is an easily accessible and cost-effective solvent system for large-scale production. High-pressure autoclave experiments demonstrated a significant enhancement in methane hydrate formation kinetics with low BS concentrations. 50 ppm of BS yielded a maximum water-to-hydrate conversion of 66.9%, equivalent to a storage capacity of 119.9 v/v in distilled water. With increasing BS concentration to 500 ppm, the conversion degree and storage capacity reached 97% and 162.6 v/v, respectively. Molecular dynamic simulation revealed that BS molecules acted as collectors for methane molecules, augmenting hydrate growth rate and increasing the number of hydrate cavities. Additionally, BS demonstrated a biodegradability exceeding 60% within 28 days.

Keywords: solidified methane, gas storage, gas hydrates, green surfactant, gas hydrate promoter, computational simulation, sustainability

Procedia PDF Downloads 6

Authors: Adhithy Menon E., Biju C. A.

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In the 1960s, the concept of preserving heritage monuments was first introduced. During the 1990s, the concept of cultural landscapes gained importance, highlighting the importance of culture and heritage. Throughout this paper, we examine the second category of the cultural landscape, which is an organically evolving landscape as it represents a web of tangible, intangible, and ecological heritage and the ways in which they can be rejuvenated. Cultural landscapes in various regions, such as the Chettinad Village clusters, are in serious decline, which is identified through the Heritage Passport program of this area (2007). For this reason, it is necessary to conduct a detailed analysis of the factors that contribute to this degradation to ensure its protection in the future. An analysis of the cultural landscape of the Chettinad Village clusters and its impact on the community is presented in this paper. The paper follows the first objective, which is to understand cultural landscapes and their different criteria and categories. It is preceded by the study of various methods for protecting cultural landscapes. To identify a core area of intervention based on the parameters of Cultural Landscapes and Community Based Tourism, a study and analysis of the regional context of Chettinad village clusters considering tourism development must first be conducted. Lastly, planning interventions for integrating community-based tourism in Chettinad villages for the purpose of rejuvenating the cultural landscapes of the villages as well as their communities. The major findings include the importance of the local community in protecting cultural landscapes. The parameters identified to have an impact on Chettinad Village clusters are a community (community well-being, local maintenance, and enhancement, demand, alternative income for community, public participation, awareness), tourism (location and physical access, journey time, tourist attractions), integrity (natural factors, natural disasters, demolition of structures, deterioration of materials) authenticity (sense of place, living elements, building techniques, artistic expression, religious context) disaster management (natural disasters) and environmental impact (pollution). This area can be restored to its former glory and preserved as part of the cultural landscape for future generations by focusing on and addressing these parameters within the identified core area of the Chettinad Villages cluster (Kanadukathan TP, Kothamangalam, Kottaiyur, Athangudi, Karikudi, and Palathur).

Keywords: Chettinad village clusters, community, cultural landscapes, organically evolved.

Procedia PDF Downloads 82

Authors: S. Thaiudom, W. Toommuangpak

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Yoghurt ice cream (YIC) containing prebiotics and probiotics seems to be much more recognized among consumers who concern for their health. Not only can it be a benefit on consumers’ health but also its taste and freshness provide people easily accept. However, the survival of such probiotic especially Bifidobacterium longum, found in human gastrointestinal tract and to be benefit to human gut, was still needed to study in the severe condition as whipping and freezing in ice cream process. Low and full-fat yoghurt ice cream containing 2 and 10% (w/w) fat content (LYIC and FYIC), respectively was produced by mixing 20% yoghurt containing B. longum into milk ice cream mix. Fructo-oligosaccharides (FOS) or galacto-oligosaccharides (GOS) at 0, 1, and 2% (w/w) were separately used as prebiotic in order to improve the survival of B. longum. Survival of this bacteria as a function of ice cream storage time and ice cream properties were investigated. The results showed that prebiotic; especially FOS could improve viable count of B. longum. The more concentration of prebiotic used, the more is the survival of B. Longum. These prebiotics could prolong the survival of B. longum up to 60 days, and the amount of survival number was still in the recommended level (106 cfu per gram). Fat content and prebiotic did not significantly affect the total acidity and the overrun of all samples, but an increase of fat content significantly increased the fat particle size which might be because of partial coalescence found in FYIC rather than in LYIC. However, addition of GOS or FOS could reduce the fat particle size, especially in FYIC. GOS seemed to reduce the hardness of YIC rather than FOS. High fat content (10% fat) significantly influenced on lowering the melting rate of YIC better than 2% fat content due to the 3-dimension networks of fat partial coalescence theoretically occurring more in FYIC than in LYIC. However, FOS seemed to retard the melting rate of ice cream better than GOS. In conclusion, GOS and FOS in YIC with different fat content can enhance the survival of B. longum and affect physical and chemical properties of such yoghurt ice cream.

Keywords: Bifidobacterium longum, prebiotic, survival, yoghurt ice cream

Procedia PDF Downloads 161

Authors: Oya A. Urucu, Aslı B. Çiğil, Hatice Birtane, Ece K. Yetimoğlu, Memet Vezir Kahraman

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Chlorpyrifos is an organophosphorus pesticide which can be found in environmental water samples. The efficiency and reuse of a molecularly imprinted polymer (chlorpyrifos - MIP) were investigated for the selective removal of chlorpyrifos residues. MIP was prepared with UV curing thiol-ene polymerization technology by using multifunctional thiol and ene monomers. The thiol-ene curing reaction is a radical induced process, however unlike other photoinitiated polymerization processes, this polymerization process is a free-radical reaction that proceeds by a step-growth mechanism, involving two main steps; a free-radical addition followed by a chain transfer reaction. It assures a very rapidly formation of a uniform crosslinked network with low shrinkage, reduced oxygen inhibition during curing and excellent adhesion. In this study, thiol-ene based UV-curable polymeric materials were prepared by mixing pentaerythritol tetrakis(3-mercaptopropionate), glyoxal bis diallyl acetal, polyethylene glycol diacrylate (PEGDA) and photoinitiator. Chlorpyrifos was added at a definite ratio to the prepared formulation. Chemical structure and thermal properties were characterized by FTIR and thermogravimetric analysis (TGA), respectively. The pesticide analysis was performed by gas chromatography-mass spectrometry (GC-MS). The influences of some analytical parameters such as pH, sample volume, amounts of analyte concentration were studied for the quantitative recoveries of the analyte. The proposed MIP method was applied to the determination of chlorpyrifos in river and tap water samples. The use of the MIP provided a selective and easy solution for removing chlorpyrifos from the water.

Keywords: molecularly imprinted polymers, selective removal, thilol-ene, uv-curable polymer

Procedia PDF Downloads 301