Search results for: Tabriz wastewater treatment plant

Authors: Stephanie M. De Oliveira

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For a long time, migrations are characterized as a difficult problem to solve. Various phenomena throughout human history caused personnel migrations, whether by the free will of migrants or not. Nowadays, governments that seek to give these people protection and dignity, either to asylum or to build a new life in a different country, make refugee protection. At present, a large amount of people, have been crossing their country's borders by land, air or sea, becoming refugees and seeking a new life away from fear, threat or violence they suffered in their country of origin. It is known that some countries have already instituted rights and rules for refugees who wish to become citizens in the country to which they immigrated, even though this is not what happens in most cases. The article will be based on research made with UN Refugee Agency (UNHCR) material as well as will analyze the interaction of the Turkish government with the European Union. Since Turkey is not part of the Union, it will be understood how the interaction was made, as well as the search for consensus, and not only humanitarian but also financial aid. The treatment of refugees and the defense of human rights within the country will also be considered.

Keywords: refugees, Turkey, asylum seekers, United Nations

Procedia PDF Downloads 370

Authors: Nujuree Sukasame

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This paper is entitled"The Improving Students on Phrasal Verbs Through movie with the grade10th Grade Students of Demonstration School of Khon Kaen University in the Academic year 2014..The sample group consitsed of30 the Grade students ofDemonstration School randomized by Purposive Sampling. The purpose of this research is to improve students"ability in phrasal verbs through movie at prescribe criteria 70%.It was used as the researcher treatment to encourage students to develope phrasal verbs on movie.Two types of instruments used were phrasal verbs test and attitude questionnaires.The research desige used was One grop Pre-test Post-test Design methode and analyzed by percentage and means. The result showed that in the pre-test and the post-test the mean scores were10.30% and 26% respectively.The result of t-test indicated statistically t=-3.077.It significant difference was at0.1.From the above result, It is noticed that the students"ability on phrasal verbs was improved significantly through movie.

Keywords: the improving, phrasal verbs, movie, students

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Authors: Mohammed S. Alqahtani, Paulo J. Bartolo

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External fixation is a common technique for the treatment and stabilization of bone fractures. Different designs have been proposed by companies and research groups, but all of them present limitations such as high weight, not comfortable to use, and not customized to individual patients. This paper proposes a lightweight customized external fixator, overcoming some of these limitations. External fixators are designed using a set of techniques such as medical imaging, CAD modelling, finite element analysis, and full factorial design of experiments. Key design parameters are discussed, and the optimal set of parameters is used to design the final external fixator. Numerical simulations are used to validate design concepts. Results present an optimal external fixation design with weight reduction of 13% without compromising its stiffness and structural integrity. External fixators are also designed to be additively manufactured, allowing to develop a strategy for personalization.

Keywords: computer-aided design modelling, external fixation, finite element analysis, full factorial, personalization

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Authors: Natalia Constantinescu

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This cross-sectional study aims to explore the differences among adults with somatic symptom disorder (SSD) versus adults without SSD in terms of attachment and emotion regulation strategies. A total sample of 80 participants (40 people with SSD and 40 healthy controls), aged 20-57 years old (M = 31.69, SD = 10.55), were recruited from institutions and online groups. They completed the Romanian version of the Experiences in Close Relationships Scale – Short Form (ECR-S), Regulation of Emotion Systems Survey (RESS), Patient Health Questionnaire-15 (PHQ-15) and Somatic Symptom Disorder – B Criteria Scale (SSD-12). The results indicate significant differences between the two groups in terms of attachment and emotion regulation strategies. Adults with SSD have a higher level of attachment anxiety and avoidance compared to the nonclinical group. Moreover, people with SSD are more prone to use rumination and suppression and less prone to use reevaluation compared to healthy people. Implications for SSD prevention and treatment are discussed.

Keywords: adult attachment, emotion regulation strategies, psychosomatic disorders, somatic symptom disorder

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Authors: Oibar Martinez, Clara Oliver, Jose Miguel Miranda

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In this paper, we discuss the standard improvements which can be made to reduce the earth resistance in difficult terrains for optimum lightning protection, what are the practical limitations, and how the modeling can be refined for accurate diagnostics and ground resistance minimization. Ground resistance minimization can be made via three different approaches: burying vertical electrodes connected in parallel, burying horizontal conductive plates or meshes, or modifying the own terrain, either by changing the entire terrain material in a large volume or by adding earth-enhancing compounds. The use of vertical electrodes connected in parallel pose several practical limitations. In order to prevent loss of effectiveness, it is necessary to keep a minimum distance between each electrode, which is typically around five times larger than the electrode length. Otherwise, the overlapping of the local equipotential lines around each electrode reduces the efficiency of the configuration. The addition of parallel electrodes reduces the resistance and facilitates the measurement, but the basic parallel resistor formula of circuit theory will always underestimate the final resistance. Numerical simulation of equipotential lines around the electrodes overcomes this limitation. The resistance of a single electrode will always be proportional to the soil resistivity. The electrodes are usually installed with a backfilling material of high conductivity, which increases the effective diameter. However, the improvement is marginal, since the electrode diameter counts in the estimation of the ground resistance via a logarithmic function. Substances that are used for efficient chemical treatment must be environmentally friendly and must feature stability, high hygroscopicity, low corrosivity, and high electrical conductivity. A number of earth enhancement materials are commercially available. Many are comprised of carbon-based materials or clays like bentonite. These materials can also be used as backfilling materials to reduce the resistance of an electrode. Chemical treatment of soil has environmental issues. Some products contain copper sulfate or other copper-based compounds, which may not be environmentally friendly. Carbon-based compounds are relatively inexpensive and they do have very low resistivities, but they also feature corrosion issues. Typically, the carbon can corrode and destroy a copper electrode in around five years. These compounds also have potential environmental concerns. Some earthing enhancement materials contain cement, which, after installation acquire properties that are very close to concrete. This prevents the earthing enhancement material from leaching into the soil. After analyzing different configurations, we conclude that a buried conductive ring with vertical electrodes connected periodically should be the optimum baseline solution for the grounding of a large size structure installed on a large resistivity terrain. In order to show this, a practical example is explained here where we simulate the ground resistance of a conductive ring buried in a terrain with a resistivity in the range of 1 kOhm·m.

Keywords: grounding improvements, large scale scientific instrument, lightning risk assessment, lightning standards

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Authors: Patel Himeshkumar Ashokbhai, Suchit Sharma, Arvind Kumar Garg

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The results obtained from settling test of coal fines are used as an important tool to select the dewatering equipment such as thickeners, centrifuges and filters. Coal being hydrophobic in nature does not easily settle when mixed with water. Coal slurry that takes longer time to release water is highly undesirable because it poses additional challenge during sedimentation, centrifuge and filtration. If filter cake has higher than permitted moisture content then it not only creates handling problems but inflated freight costs and reduction in input and productivity for coke oven charges. It is to be noted that coal fines drastically increase moisture percentage in filter cake hence are to be minimized. To increase settling rate of coal fines in slurry chemical substances called flocculants or coagulants are added that cause coal particles to flocculate or coalesce into larger particles. These larger particles settle at faster rate and have higher settling velocity. Other important factors affecting settling rate are flocculent dosage, slurry or pulp density and particle size. Hence in this paper we tried to study the settling characteristic of clean coal fines by varying one of the four factors namely 1. Flocculant Dosage (acryl-amide) 2. pH of the water 3. Bulk density 4. Particle size of clean coal fines in settling experiment and drew important conclusions. Result of this paper will be much useful not only for coal beneficiation plant design but also for cost reduction of coke production facilities.

Keywords: bulk density, coal fines, flocculants, flocculation, settling velocity, pH

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Authors: Niki Hayatgheib, SéGolèNe Calvez, Catherine Fournel, Lionel Pineau, Herve Pouliquen, Emmanuelle Moreau

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Furunculosis caused by infection with Aeromonas salmonicida subsp. salmonicida has been a known disease found principally in salmonid aquaculture. Vaccination has been partly successful in preventing this disease, but outbreaks still occur. The application of functional feed additive found to be a promising yield to improve fish health against diseases. In this study, we tested the efficacy of prebiotics and plant essential oils-enriched diet on immune response and disease resistance in vaccinated and non-vaccinated rainbow trout (Oncorhynchus mykiss) against furunculosis. A total of 600 fish were fed with the basal diet or supplement. On 4th week of feeding, fish were vaccinated with an autovaccine. Following 8 weeks, fish were challenged with Aeromonas salmonicida subsp. salmonicida and mortalities were recorded for 3 weeks. Lysozyme activity and antibody titer in serum were measured in different groups. The results of this study showed that lysozyme and circulatory antibody titer in plasma elevated significantly in vaccinated fish fed with additive. The best growth rate and relative percentage survival (62%) were in fish fed with a supplement, while 15% in control fish. Overall, prebiotics and essential oils association can be considered as a potential component for enhancing vaccine efficacy against furunculosis by increasing the growth performance, immune responses and disease resistance in rainbow trout.

Keywords: aeromonas salmonicida subsp. salmonicida, aquaculture, disease resistance, fish, immune response, prebiotics-essential oils feed additive, rainbow trout, vaccination

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Authors: Abdalla Ahmed Abdrabou Emam Eldeib

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For more than a century, the Hague Conference has tackled issues in the most challenging areas of private international law, including family law. Its actions in the realm of international child abduction have been remarkable in two ways during the last two decades. First, on October 25, 1980, the Hague Convention on the Civil Aspects of International Child Abduction (the Convention) was promulgated as an unusually inventive and powerful tool. Second, the Convention is rapidly becoming more prominent in the development of international child law. By that time, overseas travel had grown more convenient, and more couples were marrying or travelling across national lines. At the same time, parental separation and divorce have increased, leading to an increase in international child custody battles. The convention they drafted avoids legal quagmires and addresses extra-legal issues well. It literally restores the kid to its place of usual residence by establishing that the youngster was unlawfully abducted from that position or, alternatively, was wrongfully kept abroad after an allowed visit. Legal custody of a child of a contested parent is usually followed by the child's abduction or unlawful relocation to another country by the non-custodial parent or other persons. If a child's custodial parent lives outside of Egypt, the youngster may be kidnapped and brought to Egypt. It's natural to ask what laws should apply and what legal norms should be followed while hearing individual instances. This study comprehensively evaluates and estimates the relevant Hague Child Abduction Convention and the current situation in Egypt and which law is applicable for child custody. In addition, this research emphasis, detail, and focus on the position of Cross-border parental child abductions in Egypt. Moreover, examine the Islamic law compared to the Hague Convention on Child Custody in detail, as well as mentioning the treatment of Islamic countries in this matter in general and Egypt's treatment of this matter in particular, as well as the criticism directed at Egypt regarding the application and implementation of child custody issues. The present research backs up this method by using non-doctrinal techniques, including surveys, interviews, and dialogues. An important objective of this research is to examine the factors that contribute to parental child abduction. In this case, family court attorneys and other interested parties serve as the target audience from whom data is collected. A survey questionnaire was developed and sent to the target population in order to collect data for future empirical testing to validate the identified critical factors on Parental Child Abduction. The main finding in this study is breaking the reservations of many Muslim countries to join the Hague Convention with regard to child custody., Likewise, clarify the problems of implementation in practice in cases of kidnapping a child from one of the parents and traveling with him outside the borders of the country. Finally, this study is to provide suggestions for reforming the current Egyptian Family Law to make it an effective and efficient for all dispute's resolution mechanism and the possibility of joining The Hague Convention.

Keywords: egyptian family law, Hague child abduction convention, child custody, cross-border parental child abductions in egypt

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Authors: Foad Hassaninejadafarahani, Scott Ormiston

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Reflux condensation occurs in a vertical channels and tubes when there is an upward core flow of vapor (or gas-vapor mixture) and a downward flow of the liquid film. The understanding of this condensation configuration is crucial in the design of reflux condensers, distillation columns, and in loss-of-coolant safety analyses in nuclear power plant steam generators. The unique feature of this flow is the upward flow of the vapor-gas mixture (or pure vapor) that retards the liquid flow via shear at the liquid-mixture interface. The present model solves the full, elliptic governing equations in both the film and the gas-vapor core flow. The computational mesh is non-orthogonal and adapts dynamically the phase interface, thus produces sharp and accurate interface. Shear forces and heat and mass transfer at the interface are accounted for fundamentally. This modeling is a big step ahead of current capabilities by removing the limitations of previous reflux condensation models which inherently cannot account for the detailed local balances of shear, mass, and heat transfer at the interface. Discretisation has been done based on a finite volume method and a co-located variable storage scheme. An in-house computer code was developed to implement the numerical solution scheme. Detailed results are presented for laminar reflux condensation from steam-air mixtures flowing in vertical parallel plate channels. The results include velocity and pressure profiles, as well as axial variations of film thickness, Nusselt number and interface gas mass fraction.

Keywords: Reflux, Condensation, CFD-Two Phase, Nusselt number

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Authors: Nour Elhouda Abed, Bedj Mimi, Wahid Slimani, Mourad Atif, Abdelhakim Ouzzane, Hocine Irekti, Abdelkader Bekki

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The most frequent system of cereal production in Algeria is fallow-wheat. This is an extensive system that meets only the half needs some cereals and fodder demand. Resorption of fallow has become a strategic necessity to ensure food security in response to the instability of supply and the persistence of higher food prices on the world market. Despite several attempts to replace the fallow by crop cultures, choosing the best crop remains. Today, the agronomic and economic interests of legumes are demonstrated. However, their crop culture remains marginalized because of the weakness and instability of their performance. In the context of improving legumes and cereals crops as well as fallow resorption, we undertook to test, in the field, the effect of rhizobial inoculation of Phaseolus vulgaris in association with Zea Mays. We firstly studied the genetic diversity of rhizobial strains that nodulate P.vulgaris isolated from fifteen (15) different regions. ARDRA had shown 18 different genetic profiles. Symbiotic characterization highlighted a strain that highly significantly improved the fresh and dry weight of the host plant, in comparison to the negative control (un-inoculated) and the positive control (inoculated with the reference strain CIAT 899). In the field, the selected strain increased significantly the growth and yield of P.vulgaris and Zea Mays comparing to the non-inoculated control. However, the mix inoculation (selected strain+ Ciat 899) had not given the best parameters showing, thus, no synergy between the strains. These results indicate the replacing fallow by a crop legume in intercropping with cereals crops.

Keywords: fallow, intercropping, inoculation, legumes-cereals

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Authors: Philip Vercoe, Ali Hardan

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Samples of 29 Australian wild natives and exotic plants were tested in vitro batch rumen culture system for their methanogenic characteristics and potential usage as feed or antimicrobial to enhance sustainable livestock ruminant production system. The plants were tested for their in vitro rumen fermentation end products properties which include: methane production, total gas pressure, concentrations of total volatile fatty acids, ammonia, and acetate to propionate ratio. All of the plants were produced less methane than the positive control (i.e., oaten chaff) in vitro. Nearly 50 % of plants inhibiting methane by over 50% in comparison to the control. Eremophila granitica had the strongest inhibitory effect about 92 % on methane production comparing with oaten chaff. The exotic weed Arctotheca calendula (Capeweed) had the highest concentration of volatile fatty acids production as well as the highest in total gas pressure among all plants and the control. Some of the acacia species have the lowest production of total gas pressure. The majority of the plants produced more ammonia than the oaten chaff control. The plant species that produced the most ammonia was Codonocarpus cotinifolius, producing over 3 times as much methane as oaten chaff control while the lowest was Eremophila galeata. There was strong positive correlation between methane production and total gas production as well as between total gas production and the concentration of VFA produced with R² = 0.74, R² = 0.84, respectively. While there was weak positive correlation between methane production and the acetate to propionate ratio as well as between the concentration of VFA produced and methane production with R² = 0.41, R² = 0.52, respectively.

Keywords: in vitro Rumen Fermentation, methane, wild Australian native plants, forages

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Authors: Zhuang Ma, Zihan Zhang, Yu Li

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Environmental concerns from stakeholders (e.g., governments & customers) have pushed firms to integrate environmental management systems into business processes such as R&D, manufacturing, and marketing. Environmental systems include managing environmental risks and pollution control (e.g., air pollution control, waste-water treatment, noise control, energy recycling & solid waste treatment) through raw material management, the elimination and reduction of contaminants, recycling, and reuse in firms' operational processes. Despite increasing studies on firms' proactive adoption of environmental management, their focus is primarily on large corporations operating in developed economies. Investigations in the environmental management efforts of small and medium-sized enterprises (SMEs) are scarce. This is problematic for SMEs because, unlike large corporations, SMEs have limited awareness, resources, capabilities to adapt their operational routines to address environmental impacts. The purpose of this study is to explore how SMEs develop organizational capabilities through interactions with business partners (e.g., environmental management specialists & customers). Drawing on the resource-based view (RBV) and an organizational capabilities perspective, this study investigates the interactively developed capabilities that allow SMEs to adopt environmental management systems. Using an exploratory approach, the study includes 12 semi-structured interviews with senior managers from four SMEs, two environmental management specialists, and two customers in the pharmaceutical sector in Chongqing, China. Findings of this study include four key organizational capabilities: 1) ‘dynamic marketing’ capability, which allows SMEs to recoup the investments in environmental management systems by developing environmentally friendly products to address customers' ever-changing needs; 2) ‘process improvement’ capability, which allows SMEs to select and adopt the latest technologies from biology, chemistry, new material, and new energy sectors into the production system for improved environmental performance and cost-reductions; and 3) ‘relationship management’ capability which allows SMEs to improve corporate image among the public, social media, government agencies, and customers, who in turn help SMEs to overcome their competitive disadvantages. These interactively developed capabilities help SMEs to address larger competitors' foothold in the local market, reduce market constraints, and exploit competitive advantages in other regions (e.g., Guangdong & Jiangsu) of China. These findings extend the RBV and organizational capabilities perspective; that is, SMEs can develop the essential resources and capabilities required for environmental management through interactions with upstream and downstream business partners. While a limited number of studies did highlight the importance of interactions among SMEs, customers, suppliers, NGOs, industrial associations, and consulting firms, they failed to explore the specific capabilities developed through these interactions. Additionally, the findings can explain how a proactive adoption of environmental management systems could help some SMEs to overcome the institutional and market restraints on their products, thereby springboarding into larger, more environmentally demanding, yet more profitable markets compared with their existing market.

Keywords: capabilities, environmental management systems, interactions, SMEs

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Authors: Amanda Rebman

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This paper challenges the criminal justice system’s traditional stance regarding prostitution. Historically, the acceptance and morality of prostitution within the United States has fluctuated depending upon the social attitudes of the era. Today, prostitutes are allegedly viewed as victims; however, they are treated like criminals throughout the criminal justice system and society. Dominant patriarchal narratives within the United States has resulted in woman lacking autonomy over their bodies and diminished their ability to choose their own career. Even though prostitutes are deemed victims, many times, they are convicted of crimes, a practice that results in further victimization. Utilizing the socialist feminist theory to understand these juxtaposing positions on whether to legalize prostitution facilitates a greater understanding of how patriarchal capitalist arrangements ensure the oppression of women throughout the criminal justice system. The legalization of prostitution will alleviate some of this oppression and ensure a more equal treatment of women in the criminal justice system and society at large.

Keywords: equality, feminist theory, prostitution, sex work

Procedia PDF Downloads 139

Authors: Ahlem Nefzi, Rania Aydi Ben Abdallah, Hayfa Jabnoun-Khiareddine, Ammar Nawaim, Rabiaa Haouala, Mejda Daami-Remadi

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Seven endophytic fungi were isolated from the wild Solanaceous species Lycium arabicum growing in the Tunisian Centre-East and were assessed for their ability to suppress Fusarium Crown and Root Rot disease caused by Fusarium oxysporum f. sp. radicis lycopersici (FORL) and to enhance plant growth. Fungal isolates were shown able to colonize tomato cv. Rio Grande roots, crowns, and stems. A significant promotion in all studied growth parameters (root length, shoot height, and roots and shoots fresh weight) was recorded in tomato plants treated with fungal conidial suspensions or their cell-free culture filtrates compared to FORL-inoculated or pathogen-free controls. I15 and I18 isolates were shown to be the most effective leading to 85.7-87.5 and 93.6-98.4% decrease in leaf and root damage index and the vascular discoloration extent, respectively, over FORL-inoculated and untreated control. These two bioactive and growth-promoting isolates (I15 and I18) were morphologically characterized and identified using rDNA sequencing gene as being Alternaria alternata (MF693801) and Fusarium fujikuroi (MF693802). These fungi significantly suppressed FORL mycelial growth and showed chitinolytic, proteolytic and amylase activities whereas only F. fujikuroi displayed a lipolytic activity. This study clearly demonstrated the potential use of fungi naturally associated with L. arabicum as biocontrol and bio-fertilizing agents.

Keywords: biocontrol, endophytic fungi, Fusarium oxysporum f. sp. radicis-lycopersici, tomato promotion, Lycium arabicum

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Authors: Agustyas Tjiptaningrum, Intanri Kurniati, Fadilah Fadilah, Linda Erlina, Tiwuk Susantiningsih

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Coronavirus disease-19 (COVID-19) is still one of the health problems. It can be a severe condition that is caused by a cytokine storm. In a cytokine storm, several proinflammatory cytokines are released massively. It destroys epithelial cells, and subsequently, it can cause death. The anti-inflammatory agent can be used to decrease the number of severe Covid-19 conditions. Melaleuca cajuputi is a plant that has antiviral, antibiotic, antioxidant, and anti-inflammatory activities. This study was carried out to analyze the prediction mechanism of the M. cajuputi extract from Lampung, Indonesia, as an anti-inflammatory agent for COVID-19. This study constructed a database of protein host target that was involved in the inflammation process of COVID-19 using data retrieval from GeneCards with the keyword “SARS-CoV2”, “inflammation,” “cytokine storm,” and “acute respiratory distress syndrome.” Subsequent protein-protein interaction was generated by using Cytoscape version 3.9.1. It can predict the significant target protein. Then the analysis of the Gene Ontology (GO) and KEGG pathways was conducted to generate the genes and components that play a role in COVID-19. The result of this study was 30 nodes representing significant proteins, namely NF-κβ, IL-6, IL-6R, IL-2RA, IL-2, IFN2, C3, TRAF6, IFNAR1, and DOX58. From the KEGG pathway, we obtained the result that NF-κβ has a role in the production of proinflammatory cytokines, which play a role in the COVID-19 cytokine storm. It is an important factor for macrophage transcription; therefore, it will induce inflammatory gene expression that encodes proinflammatory cytokines such as IL-6, TNF-α, and IL-1β. In conclusion, the blocking of NF-κβ is the prediction mechanism of the M. cajuputi extract as an anti-inflammation agent for COVID-19.

Keywords: antiinflammation, COVID-19, cytokine storm, NF-κβ, M. cajuputi

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Authors: Mohamed A. Adam Abakar, Abdullah M. Asiri, Sher Bahadar Khan

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In this paper, nickel oxide-zinc oxide (NiO-ZnO) catalyst was embedded in an alginate polymer (Na alg/NiO-ZnO), a nanocomposite that was used as a nano-catalyst for catalytic conversion of deleterious contaminants such as organic dyes (Acridine Orange “ArO”, Methylene Blue “MB”, Methyl Orange “MO”) and 4-Nitrophenol “4-NP” as well. FESEM, EDS, FTIR and XRD techniques were used to identify the shape and structure of the nano-catalyst (Na alg/NiO-ZnO). UV spectrophotometry is used to collect the results and it showed greater and faster reduction rate for MB (illustrated in figures 2, 3, 4 and 5). Data recorded and processed, drawing and analysis of graphs achieved by using Origin 2018. Reduction percentage of MB was assessed to be 95.25 % in just 13 minutes. Furthermore, the catalytic property of Na alg/NiO-ZnO in the reduction of organic dyes was investigated using various catalyst amounts, dye types, reaction times and reducing agent dosages at room temperature (rt). NaBH4-assisted reduction of organic dyes was studied using alg/NiO-ZnO as a potential catalyst.

Keywords: Alginate, metal oxides, nanocomposites-based, catalysts, reduction, photocatalytic degradation, water treatment

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Authors: Onan Kilicaslan, Anil Kabaklarli, Levent Subasi, Erdem Bektas, Rifat Yilmaz

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The Aluminum-Copper casting alloys are well known for their high mechanical strength, especially when compared to more commonly used Aluminum-Silicon alloys. A201 is one of the best in terms of strength vs. weight ratio among other aluminum alloys, which makes it suitable for premium quality casting applications in aerospace and automotive industries. It is reported that A201 has low castability, but it is easy to machine. However, there is a need to specifically determine the process window for feasible machining. This research investigates the machinability of A201 alloy after T7 heat treatment in terms of chip/burr formation, surface roughness, hardness, and microstructure. The samples are cast with low-pressure sand casting method and milling experiments are performed with uncoated carbide tools using different cutting speeds and feeds. Statistical analysis is used to correlate the machining parameters to surface integrity. It is found that there is a strong dependence of the cutting conditions on machinability and a process window is determined.

Keywords: A201-T7, machinability, milling, surface integrity

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Authors: D. Kuvshinov, A. Siswanto, W. Zimmerman

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A phorbol-12-myristate-13-acetate (TPA) is a synthetic analogue of phorbol ester (PE), a natural toxic compound of Euphorbiaceae plant. The oil extracted from plants of this family is useful source for primarily biofuel. However this oil can also be used as a food stock due to its significant nutrition content. The limitations for utilizing the oil as a food stock are mainly due to a toxicity of PE. Nowadays a majority of PE detoxification processes are expensive as include multi steps alcohol extraction sequence. Ozone is considered as a strong oxidative agent. It reaction with PE it attacks the carbon double bond of PE. This modification of PE molecular structure results into nontoxic ester with high lipid content. This report presents data on development of simple and cheap PE detoxification process with water application as a buffer and ozone as reactive component. The core of this new technique is a simultaneous application of new microscale plasma unit for ozone production and patented gas oscillation technology. In combination with a reactor design the technology permits ozone injection to the water-TPA mixture in form of microbubbles. The efficacy of a heterogeneous process depends on diffusion coefficient which can be controlled by contact time and interface area. The low velocity of rising microbubbles and high surface to volume ratio allow fast mass transfer to be achieved during the process. Direct injection of ozone is the most efficient process for a highly reactive and short lived chemical. Data on the plasma unit behavior are presented and influence of the gas oscillation technology to the microbubbles production mechanism has been discussed. Data on overall process efficacy for TPA degradation is shown.

Keywords: microbubble, ozonolysis, synthetic phorbol ester, chemical engineering

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Authors: Ghoutia Naima Sabri, Tayeb Benouaz

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The interaction between wave and electron cyclotron movement when the electron passes through a layer of resonance at a fixed frequency results an Electron Cyclotron (EC) absorption in Tokamak plasma and dependent magnetic field. This technique is the principle of additional heating (ECRH) and the generation of non-inductive current drive (ECCD) in modern fusion devices. In this paper we are interested by the problem of EC absorption which used a microscopic description of kinetic theory treatment versus the propagation which used the cold plasma description. The power absorbed depends on the optical depth which in turn depends on coefficient of absorption and the order of the excited harmonic for O-mode or X-mode. There is another possibility of heating by dissipation of Alfven waves, based on resonance of cold plasma waves, the shear Alfven wave (SW) and the compressional Alfven wave (FW). Once the (FW) power is coupled to (SW), it stays on the magnetic surface and dissipates there, which cause the heating of bulk plasmas.

Keywords: electron cyclotron, heating, plasma, tokamak

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Authors: Khalid A. Rabaeh, Belal Moftah, Ahmed A. Basfar, Akram A. Almousa

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Polymer gel dosimeters are tissue equivalent martial that fabricated from radiation sensitive chemicals which, upon irradiation, polymerize as a function of absorbed radiation dose. Polymer gel dosimeters can uniquely record the radiation dose distribution in three-dimensions (3D). A novel composition of normoxic polymer gel dosimeters based on radiation-induced polymerization of N-(Hydroxymethyl)acrylamide (NHMA) is introduced in this study for radiotherapy treatment planning. The dosimeters were irradiated by 10 MV photon beam of a medical linear accelerator at a constant dose rate of 600 cGy/min with doses up to 30 Gy. The polymerization degree is directly proportional to absorbed dose received by the polymer gel. UV/Vis spectrophotometer was used to investigate the degree of white color of irradiated NHMA gel which is associated to the degree of polymerization of polymer gel dosimeters. The absorbance increases with absorbed dose for all gel dosimeters in the dose range between 0 and 30 Gy. Dose rate , energy of radiation and the stability of the polymerization after irradiation were investigated. No appreciable effects of these parameters on the performance of the novel gel dosimeters were observed.

Keywords: dosimeter, gel, spectrophotometer, N-(Hydroxymethyl)acrylamide

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Authors: Z. Mahi, L. Marousset, C. Roudaut, M. Belkhodja, R. Lemoine

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The strong accumulation of salts in the soil as well as in irrigation water greatly disrupts the growth and development of almost all plants. The study of these disturbances in halophytes helps provide better guidance on the deteriorating effect of salinity. Evaluation of salt stress in two species of Atriplex (halimus and canescens) through the study of mineral nutrition (dosage of sodium and potassium) shows a variability of responses. The results show that the Na+ ion accumulates in the three organs whatever the applied concentration. This accumulation increases with the high salt concentrations in halimus whereas in canescens, 600 mM treatment shows a reduction of the amount of this element. A decrease in the amount of potassium is observed for all organs except halimus rods 100 mM. Unlike halimus, canescens K + accumulates in high concentrations of salt at the roots and leaves. The ratio Na+/K+ decreases the salt by halimus against it increases in levels canescens roots and treated with high concentrations of NaCl (600 mM) leaves.

Keywords: Atriplex, canescens, halimus, Na +, K +, Na Cl, tolerance

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Authors: Charmaine Lamiel, Van Hoa Nguyen, Jae-Jin Shim

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Supercapacitors are energy storage devices capable of storing more energy than conventional capacitors and have higher power density than batteries. The advantages of this method include the non-use of reducing agents and acidic medium, and no further use of a post-heat treatment unlike the conventional processes, in which calcination is generally employed after obtaining the initial product. Furthermore, it also offers a shorter reaction time at low temperatures and low power requirements, which allows low fabrication and energy cost. In this study, microwave irradiation was used for the facile and rapid synthesis of mesoporous RGO@(Co,Mn)3O4 nanosheets as an electrode material. The as-prepared electrode exhibited a high capacitance of 953 F•g^−1 at 1 A•g^−1 in a 6 M KOH electrolyte solution. Moreover, the electrode exhibited a high energy density of 76.2 Wh•kg^−1 at a power density of 720 W•kg^−1, and a high power density of 7200 W•kg^−1 at an energy density of 38 Wh•kg^−1. The successful methodology was considered to be efficient and cost-effective, thereby providing an active electrode material with very promising electrochemical performance.

Keywords: cobalt-manganese oxide, electrochemical, graphene, microwave synthesis, supercapacitor

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Authors: S. C. Santos, S. R. Dionísio, A. L. D. De Andrade, L. R. Roque, A. C. Da Costa, J. L. Ienczak

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In this work, two fermentations at different temperatures (25 and 30 ºC), with cell recycling, were accomplished to produce ethanol, using a mix of commercial substrates, xylose (70%) and glucose (30%), as organic source for Scheffersomyces stipitis. Five consecutive fermentations of 80 g L-1 (1º, 2º and 3º recycles), 96 g L-1 (4º recycle) and 120 g L-1 (5º recycle)reduced sugars led to a final maximum ethanol concentration of 17.2 and 34.5 g L-1, at 25 and 30 ºC, respectively. Glucose was the preferred substrate; moreover xylose startup degradation was initiated after a remaining glucose presence in the medium. Results showed that yeast acid treatment, performed before each cycle, provided improvements on cell viability, accompanied by ethanol productivity of 2.16 g L-1 h-1 at 30 ºC. A maximum 36% of xylose was retained in the fermentation medium and after five-cycle fermentation an ethanol yield of 0.43 g ethanol/g sugars was observed. S. stipitis fermentation capacity and tolerance showed better results at 30 ºC with 83.4% of theoretical yield referenced on initial biomass.

Keywords: 5-carbon sugar, cell recycling fermenter, mixed sugars, xylose-fermenting yeast

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Authors: Xiaoxin Ye, Guoyi Tang

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The effect of electropulsing ultrasonic shock (EUS) on the surface hardening and microstructure of Ti6Al4V alloy was studied. It was found that electropulsing improved the microhardness dramatically both in the influential depth and maximum value, compared with the only ultrasonic-shocked sample. It’s indicated that refined surface layer with nanocrystalline and improved microhardness were obtained on account of surface severe plastic deformation, dynamic recrystallization (DRX) and phase change, which was implemented at relative low temperature and high strain rate/capacity due to the coupling of the thermal and athermal effects of EUS. It’s different from conventional experiments and theory. It’s discussed that the positive contributions of EPT in the thermodynamics and kinetics of microstructure and properties change were attributed to the reduction of nucleation energy barrier and acceleration of atomic diffusion. Therefore, it’s supposed that EUS is an energy-saving and high-efficiency method of surface treatment technique with the help of high-energy electropulses, which is promising in cost reduction of the surface engineering and energy management.

Keywords: titanium alloys, electropulsing, ultrasonic shock, microhardness, nanocrystalline

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Authors: Isabela S. Gonçalves, Vitor G. P. Lima, Tiago M. B. Campos, Marcos Jacobovitz, Luana M. R. Vasconcellos, Ivone R. Oliveira

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Periodontitis is an infectious disease of multifactorial origin, which originates from a periodontogenic bacterial biofilm that colonizes the surfaces of the teeth, resulting in an inflammatory reaction to microbial aggression. In the absence of adequate treatment, it can lead to the gradual destruction of the periodontal ligaments, cementum and alveolar bone. In guided tissue/bone regeneration therapy (GTR/GBR), a barrier membrane is placed between the fibrous tissues and the bone defect to prevent unwanted incursions of fibrous tissues into the bone defect, thus allowing the regeneration of quality bone. Currently, there are a significant number of biodegradable barrier membranes available on the market. However, a very common problem is that the membranes are not bioactive/osteogenic, that is, they are incapable of inducing a favorable osteogenic response and integration with the host tissue, resulting in many cases in displacement/expulsion of the membrane, requiring a new surgical procedure and replacement of the implant. Aiming to improve the bioactive and osteogenic properties of the membrane, this work evaluated the production of membranes that integrate the biocompatibility of the hydrophilic synthetic polymer (polyvinyl alcohol - PVA) with the osteogenic effects of chlorinated bioactive glasses (BG58S-Cl), using the electrospinning equipment (AeroSpinner L1.0 from Areka) which allows the execution of spinning by high voltage and/or blowing in solution and with a high production rate, enabling development on an industrial scale. In the formulation of bioactive glasses, the replacement of nitrates by chlorinated molecules has shown to be a promising alternative, since the chloride ion is naturally present in the body and, with its presence in the bioactive glass, the biocompatibility of the material increases. Thus, in this work, chlorinated bioactive glasses were synthesized by the sol-gel route using the compounds tetraethyl orthosilicate (TEOS), calcium chloride dihydrate and monobasic ammonium phosphate with pH adjustments with 37% HCl (1.5 or 2.5) and different calcination temperatures (500, 600 and 700 °C) were evaluated. The BG-58S-Cl powders obtained were characterized by pH, conductivity and zeta potential x time curves and by SEM/FEG, FTIR-ATR and Raman tests. The material produced under the selected conditions was evaluated in relation to the milling procedure, obtaining particles suitable for incorporation into PVA polymer solutions to be electrospun (D50 = 22 µm). Membranes were produced and evaluated regarding the influence of the crosslinking agent content as well as the crosslinking treatment temperature (3, 5 and 10 wt% citric acid) and (130 or 175 oC) and were characterized by SEM/FEG, FTIR, TG and DSC. From the optimization of the crosslinking conditions, membranes were prepared by adding BG58S-Cl powder (5 and 10 wt%) to the PVA solutions and were characterized by SEM-FEG, DSC, bioactivity in SBF and behavior in cell culture (cell viability, total protein content, alkaline phosphatase, mineralization nodules). The micrographs showed homogeneity of the distribution of BG58S-Cl particles throughout the sample, favoring cell differentiation.

Keywords: barrier membranes, chlorinated bioactive glasses, polyvinyl alcohol, tissue regeneration.

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Authors: K. Mehmood, Muhammad Asif Rafiq, A. Nasir Khan, M. Mudassar Rauf

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Air plasma spraying system was utilized to deposit Ni3Al coatings on AISI 321 steel samples. After thermal spraying, the nickel aluminide intermetallic coatings were isothermal heat treated at various temperatures. In this regard, temperatures from 500 °C to 800 °C with 100 °C increments were selected. The coatings were soaked for 10, 30, 60 and 100 hours at the mentioned temperatures. These coatings were then tested by a pin on disk method. It was observed that the coatings exposed at comparatively higher temperature experienced lower wear rate. The decrease in wear rate is due to the formation of NiO phase. Further, the as sprayed and heat treated coatings were characterized by other tools such as Microhardness testing, optical and scanning electron microscopy (SEM) and X-Ray diffraction analysis. After isothermal heat treatment, NiO was observed the main phase by X-Ray diffraction technique. Moreover, the surface hardness was also determined higher than cross sectional hardness.

Keywords: air plasma spraying, Ni -20Al, tribometer, intermetallic coating, nickel aluminide

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Authors: Nneka Augustina Akwu, Yougasphree Naidoo

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Molecular advancement in technology has created a means whereby the atoms and molecules (solid forms) of certain materials such as plants, can now be reduced to a range of 1-100 nanometres. Green synthesis of silver nanoparticles (AgNPs) was carried out at room temperature (RT) 25 ± 2°C and 80°C, using the metabolites in the aqueous extracts of the leaves and stem bark of Grewia lasiocarpa as reductants and stabilizing agents. The biosynthesized AgNPs were characterized by UV-Vis spectrophotometry, attenuated total reflectance - Fourier transforms infrared (ATR-FTIR) spectroscopy, nanoparticle tracking analysis (NTA), Energy Dispersive X-ray fluorescence scanning electron microscope (SEM-EDXRF) and high-resolution transmission electron microscopy (HRTEM). The AgNPs were biologically evaluated for antioxidant, antibacterial and cytotoxicity activities. The phytochemical and FTIR analyses revealed the presence of metabolites that act as reducing and capping agents, while the UV-Vis spectroscopy of the biosynthesized NPs showed absorption between 380-460 nm, confirming AgNP synthesis. The Zeta potential values were between -9.1 and -20.6 mV with a hydrodynamics diameter ranging from 38.3 to 46.7 nm. SEM and HRTEM analyses revealed that AgNPs were predominately spherical with an average particle size of 2- 31 nm for the leaves and 5-27 nm for the stem bark. The cytotoxicity IC50 values of the AgNPs against HeLa, Caco-2 and MCF-7 were >1 mg/mL. The AgNPs were sensitive to all strains of bacteria used, with methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 25922) being more sensitive to the AgNPs. Our findings propose that antibacterial and anticancer agents could be derived from these AgNPs of G. lasiocarpa, and warrant their further investigation.

Keywords: antioxidant, cytotoxicity, Grewia lasiocarpa, silver nanoparticles, Zeta potentials

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Authors: Omid Ghollipoor Bashiri, Farzam Hatefi

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Dichlorvos a synthetic organophosphate poisons are used as insecticide. These toxins can be used insecticides in agriculture and medicine for destruction and/or eradication of ectoparasites of animals. Studies have shown that Dichlorvos creation seizure effects in different animals. Amlodipine, dihydropyridine calcium channel blockers, widely used for treatment of cardiovascular diseases. Studies have shown that the calcium channel blockers are anticonvulsant effects in different animal models. The aim of this study was to determine the effect of Amlodipine on Dichlorvos-induced seizures in mice. In this experiment, the animals were received different doses of Amlodipine (2.5, 5, 10, 20 and 40 mg/ kg b.wt.) intraperitoneally 30 min before intraperitoneal injection of Dichlorvos (50 mg/kg b.wt). After Dichlorvos injection, clonic and tonic seizures, and finally was the fate was investigated. Results showed that Amlodipine dose-dependently reduced the severity of Dichlorvos-induced seizures, so that Amlodipine at a dose of 5mg (The lowest, p<0.05) and 40 mg/kg b.wt. (The highest, p<0.001) which had anticonvulsant effects. The anticonvulsant activity of Amlodipine suggests that possibly due to the antagonistic effect on voltage-dependent calcium channel.

Keywords: dichlorvos, amlodipine, seizures, mice

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Authors: Adegbegi Ademuyiwa Joshua, Onoagbe Iyare

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Medicinal plants have been recognized to have therapeutic effects and they may also have toxic side effects. The present study was undertaken to investigate the effect of extracts of Cymbopogon citratus on normal rats. Blood glucose levels of all animals were determined. Biochemical studies carried out to determine the oxidative status by measuring activities of superoxide dismutase (SOD) and catalase (CAT), and in the liver, kidney and pancrease. Oral administration of ethanolic and aqueous extract of C. citratus at a doses of 200 mg/kg body weight, for a period of 30 days, caused a significant (p<0.05) reduction in blood glucose levels. Effect on hormonal profile (TSH, T3, and T4) was also determined, and was found to be significantly higher in all the administered groups when compared with control. Lipid profiles levels; Total cholesterols, triglycerides, high density lipoprotein-cholesterol and low density lipoprotein-cholesterol were significantly (p>0.05) higher for all treated rats as compared against control. SOD, catalase, GSH and Vitamin C activities in the tissues (liver, kidney and pancrease) of the rats treated with the medicinal plants were generally higher or statistical slightly similar to control. Histopathology result showed that both ethanolic and aqueous extracts (200 mg/kg body weight) of C. citratus was safer as no adverse effects were observed in the organs examined. Findings in this study showed that this plant has hypoglycemic properties and did not exert oxidative damage; in some instances, particularly in the liver, kidney and pancreas as well as its relative safety and possible use for weight gain.

Keywords: medicinal plants, blood glucose, cymbopogon citratus, hypoglycaemic, oxidative status

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Authors: Shyh-Ming Chern, Te-Hsiu Tang

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Hemicellulose is one of the major constituents of all plant cell walls, making up 15-25% of dry wood. It is a biopolymer from many different sugar monomers, including pentoses, like xylose, and hexoses, like mannose. In an effort to gasify real biomass in subcritical and supercritical water in a single process, it is necessary to understand the gasification of hemicellulose, in addition to cellulose and lignin, in subcritical and supercritical water. In the present study, xylose is chosen as the model compound for hemicellulose, since it has the largest amount in most hardwoods. Xylose is gasified in subcritical and supercritical water for the production of higher-valued gaseous products. Experiments were conducted with a 16-ml autoclave batch-type reactor. Hydrogen peroxide is adopted as the oxidant in an attempt to promote the gasification yield. The major operating parameters for the gasification include reaction temperature (400 - 600°C), reaction pressure (5 - 25 MPa), the concentration of xylose (0.05 and 0.30 M), and level of oxidant added (0 and 0.25 chemical oxygen demand). 102 experimental runs were completed out of 46 different set of experimental conditions. Product gases were analyzed with a GC-TCD and determined to be mainly composed of H₂ (10 – 74 mol. %), CO (1 – 56 mol. %), CH₄ (1 – 27 mol. %), CO₂ (10 – 50 mol. %), and C₂H₆ (0 – 8 mol. %). It has been found that the gas yield (amount of gas produced per gram of xylose gasified), higher heating value (HHV) of the dry product gas, and energy yield (energy stored in the product gas divided by the energy stored in xylose) all increase significantly with rising temperature and moderately with reducing pressure. The overall best operating condition occurred at 873 K and 10 MPa, with a gas yield of 54 mmol/g of xylose, a gas HHV of 440 kJ/mol, and an energy yield of 1.3. A seemingly unreasonably energy yield of greater than unity resulted from the external heating employed in the experiments to drive the gasification process. It is concluded that xylose can be completely gasified in subcritical and supercritical water under proper operating conditions. The addition of oxidant does not promote the gasification of xylose.

Keywords: gasification, subcritical water, supercritical water, xylose

Procedia PDF Downloads 241