Search results for: water extraction

Authors: Benedicta Asante, Catherine Trask, Brenna Bath

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Background: Waste Collection Workers’ (WCWs) activities contribute greatly to the recycling sector and are an important component of the waste management industry. As the recycling sector evolves, there is the increase in reports of injuries, particularly for common and debilitating musculoskeletal disorders such as low back disorder (LBD). WCWs are likely exposed to diverse work-related hazards that could contribute to LBD. However, there is currently no summary of the state of knowledge on the prevalence and risk factors of LBD within this workforce. Method: A comprehensive search was conducted in Ovid Medline, EMBASE, and Global Health e-publications with search term categories ‘low back disorder’ and ‘waste collection workers’. Two reviewers screened articles at title, abstract, and full-text stages. Data were extracted on study design, sampling strategy, socio-demographics, geographical region, and exposure definition, the definition of LBD, response rate, statistical techniques, LBD prevalence and risk factors. The risk of bias was assessed with a standardized tool. Results: The search of three databases generated 79 studies. Thirty-two studies met the study inclusion criteria for both title and abstract; only thirteen full-text articles met the study criteria and underwent data extraction. The majority of articles reported a 12-month prevalence of LBD between 16-74%. Although none of the included studies quantified relationships between risk factors and LBD, the suggested risk factors for LBD among WCWs included: awkward posture; lifting; pulling; pushing; repetitive motions; work duration; and physical loads. Conclusion: LBD is a major occupational health issue among WCWs. In light of these risks and future growth in this industry, further research should focus on the investigation of risk factors, with more focus on ergonomic exposure assessment, and LBD prevention efforts.

Keywords: low back pain, scavenger, waste pickers, waste collection workers

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Authors: Sara Alzahrani, Samia Bokari, Patan Khan, Muneera Alshareef, Rania Safwat, Mohammed Galal, Hamdi Alqadi, Ameerah Alzahrani, Rehab Alboraie

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Introduction & Background: Diabetes in COVID-19 patients is individual risk factor and documented in worldwide studies to contribute to disease severity, increased length of stay and higher mortality. Aggressive management of blood sugars and acute diabetic complications reduce the length of stay and mortality. Methods: Randomly selected 200 patients admitted with diabetes and COVID-19 studied. The unified treatment protocol applied for all patients and blood sugars monitored closely and optimized .Data collected on bimonthly basis and analyzed. Patients’ characteristics taken from data extraction tool (Oasis) of hospital. Median values for length of stay and post discharge FBS and RBS were calculated via Microsoft Excel tool. Mortality rates were calculated by percentages. The results monitored in the post discharge clinic was 130 mg/dl and 170 mg/dl respectively. The results compared with the standard international studies. Discussion: Diabetes in COVID-19 patients posed great challenge as increased severity and mortalities reported compared to non-diabetic. Taking a pre-emptive strategy to combat this problem by aggressively manage diabetes help in reducing length of stay and morbidity. The length of stay in studded population was 3 days as compared to 13 days in a major international study. Financial saving come from rapid turnover of beds. The mortality was 2.5 % compared to reported 7.3% in a major study, reflecting the implications of aggressive management of diabetes. Regular follow-up and support by running post-discharge clinic definitely help reducing readmissions and acute complications of uncontrolled diabetes. Conclusion: Aggressive management of diabetes in COVID-19 patients by tailored treatment protocols and dedicated teams will help to decrease the morbidity and mortality.

Keywords: diabetes, covid-19, management, mortality

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Authors: P. Chaijak, M. Lertworapreecha, C. Sukkasem

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A huge of dark color palm oil mill effluent (POME) cannot pass the discharge standard. It has been identified as the major contributor to the pollution load into ground water. Here, lignin-degrading yeast isolated from a termite nest was tested to treat the POME. Its lignin-degrading and decolorizing ability was determined. The result illustrated that Galactomyces sp. was successfully grown in POME. The decolorizing test demonstrated that 40% of Galactomyces sp. could reduce the color of POME (50% v/v) about 74-75% in 5 days without nutrient supplement. The result suggested that G. reessii has a potential to apply for decolorizing the dark wastewater like POME and other industrial wastewaters.

Keywords: decolorization, palm oil mill effluent, termite, yeast

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Authors: Mohamad Saberi, Arash Sohrabi

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Tuned liquid damper is one the passive structural control ways which has been used since mid-1980 decade for seismic control in civil engineering. This system is made of one or many tanks filled with fluid, mostly water that installed on top of the high raised structure and used to prevent structure vibration. In this article we will show how to make seismic table contain TLD system and analysis the result of using this system in our structure. Results imply that when frequency ratio approaches 1 this system can perform its best in both dissipate energy and increasing structural damping. And also results of these serial experiments are proved compatible with Hunzer linear theory behaviour.

Keywords: TLD, seismic table, structural system, Hunzer linear behaviour

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Authors: Deepak Kumar, Ravi Rajwanshi, Mohd. Aslam Yusuf, Nisha Kant Pandey, Preeti Singh, Mukesh Saxena, Neera Bhalla Sarin

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Global issues are leading to concerns over food security. These include climate change, urbanization, increase in population subsequently leading to greater energy and water demand. Futuristic approach for crop improvement involves gene pyramiding for agronomic traits that empower the plants to withstand multiple stresses. In an earlier study from the laboratory, the efficacy of overexpressing γ-tocopherol methyl transferase (γ-TMT) gene from the vitamin E biosynthetic pathway has been shown to result in six-fold increase of the most biologically active form, the α-tocopherol in Brassica juncea which resulted in alleviation of salt, heavy metal and osmoticum induced stress by the transgenic plants. The glyoxalase I (gly I) gene from the glyoxalase pathway has also been earlier shown by us to impart tolerance against multiple abioitc stresses by detoxification of the cytotoxic compound methylglyoxal in Brassica juncea. Recently, both the transgenes were pyramided in Brassica juncea lines through sexual crosses involving two stable Brassica juncea lines overexpressing γ-TMT and gly I genes respectively. The transgene integration was confirmed by PCR analysis and their mRNA expression was evident by RT-PCR analysis. Preliminary physiological investigations showed ~55% increased seed germination under 200 mM NaCl stress in the pyramided line and 81% higher seed germination under 200 mM mannitol stress as compared to the WT control plants. The pyramided lines also retained more chlorophyll content when the leaf discs were floated on NaCl (200, 400 and 600 mM) or mannitol (200, 400 and 600 mM) compared to the WT control plants. These plants had higher Relative Water Content and greater solute accumulation under stress compared to the parental plants having γ-TMT or the glyI gene respectively. The studies revealed the synergy of two components from different metabolic pathways in enhancing stress hardiness of the transgenic B. juncea plants. It was concluded that pyramiding of genes (γ-TMT and glyI) from diverse pathways can lead to enhanced tolerance to salt and mannitol stress (simulating drought conditions). This strategy can prove useful in enhancing the crop yields under various abiotic stresses.

Keywords: abiotic stress, brassica juncea, glyoxalase I, α-tocopherol

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Authors: K. Graniczkowska, N. Beloglazova, S. De Saeger

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The threat of synthetic drugs is one of the most significant current drug problems worldwide. The use of drugs of abuse has increased dramatically during the past three decades. Among others, Amphetamine-Type Stimulants (ATS) are globally the second most widely used drugs after cannabis, exceeding the use of cocaine and heroin. ATS are potent central nervous system (CNS) stimulants, capable of inducing euphoric static similar to cocaine. Recreational use of ATS is widespread, even though warnings of irreversible damage of the CNS were reported. ATS pose a big problem and their production contributes to the pollution of the environment by discharging big volumes of liquid waste to sewage system. Therefore, there is a demand to develop robust and sensitive sensors that can detect ATS and their intermediates in environmental water samples. A rapid and simple test is required. Analysis of environmental water samples (which sometimes can be a harsh environment) using antibody-based tests cannot be applied. Therefore, molecular imprinted polymers (MIPs), which are known as synthetic antibodies, have been chosen for that approach. MIPs are characterized with a high mechanical and thermal stability, show chemical resistance in a broad pH range and various organic or aqueous solvents. These properties make them the preferred type of receptors for application in the harsh conditions imposed by environmental samples. To the best of our knowledge, there are no existing MIPs-based sensors toward amphetamine and its intermediates. Also not many commercial MIPs for this application are available. Therefore, the aim of this study was to compare different techniques to obtain MIPs with high specificity towards ATS and characterize them for following use in a sensing unit. MIPs against amphetamine and its intermediates were synthesized using a few different techniques, such as electro-, thermo- and UV-initiated polymerization. Different monomers, cross linkers and initiators, in various ratios, were tested to obtain the best sensitivity and polymers properties. Subsequently, specificity and selectivity were compared with commercially available MIPs against amphetamine. Different linkers, such as lipoic acid, 3-mercaptopioponic acid and tyramine were examined, in combination with several immobilization techniques, to select the best procedure for attaching particles on sensor surface. Performed experiments allowed choosing an optimal method for the intended sensor application. Stability of MIPs in extreme conditions, such as highly acidic or basic was determined. Obtained results led to the conclusion about MIPs based sensor applicability in sewage system testing.

Keywords: amphetamine type stimulants, environment, molecular imprinted polymers, MIPs, sensor

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Authors: Samiyah Tasleem, Muhammad Abdul Haq, Syed Baqir Shyum Naqvi, Muhammad Abid Husnain, Sajjad Haider Naqvi

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The objective of the present study was: a) to investigate the antimicrobial activity of honey samples of different floral sources of Pakistan, b) to recover the phenolic acids in them as a possible contributing factor of antimicrobial activity. Six honey samples from different floral sources, namely: Trachysperm copticum, Acacia species, Helianthus annuus, Carissa opaca, Zizyphus and Magnifera indica were used. The antimicrobial activity was investigated by the disc diffusion method against eight freshly isolated clinical isolates (Staphylococci aureus, Staphylococci epidermidis, Streptococcus faecalis, Pseudomonas aeruginosa, Klebsiella pneumonia, Escherichia coli, Proteus vulgaris and Candida albicans). Antimicrobial activity of honey was compared with five commercial antibiotics, namely: doxycycline (DO-30ug/mL), oxytetracycline (OT-30ug/mL), clarithromycin (CLR–15ug/mL), moxifloxacin (MXF-5ug/mL) and nystatin (NT – 100 UT). The fractions responsible for antimicrobial activity were extracted using ethyl acetate. Solid phase extraction (SPE) was used to recover the phenolic acids of honey samples. Identification was carried out via High-Performance Liquid Chromatography (HPLC). The results indicated that antimicrobial activity was present in all honey samples and found comparable to the antibiotics used in the study. In the microbiological assay, the ethyl acetate honey extract was found to exhibit a very promising antimicrobial activity against all the microorganisms tested, indicating the existence of phenolic compounds. Six phenolic acids, namely: gallic, caffeic, ferulic, vanillic, benzoic and cinnamic acids were identified besides some unknown substance by HPLC. In conclusion, Pakistani honey samples showed a broad spectrum antibacterial and promising antifungal activity. Identification of six different phenolic acids showed that Pakistani honey samples are rich sources of phenolic compounds that could be the contributing factor of antimicrobial activity.

Keywords: Pakistani honey, antimicrobial activity, Phenolic acids eg.gallic, caffeic, ferulic, vanillic, benzoic and cinnamic acids

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Authors: Perpetua Modjadji, Sphiwe Madiba

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Background: The growth patterns of children are good nutritional indicators of their nutritional status, health, and socioeconomic level. However, the maternal factors and the belief system of the society affect the growth of children promoting undernutrition. This study determined the influence of maternal factors on growth patterns of schoolchildren in a rural site. Methods: A convergent mixed method study was conducted among 508 schoolchildren and their mothers in Dikgale Health and Demographic Surveillance System Site, South Africa. Multistage sampling was used to select schools (purposive) and learners (random), who were paired with their mothers. Anthropometry was measured and socio-demographic, obstetrical, household information, maternal influence on children’s nutrition, and growth were assessed using an interviewer administered questionnaire (quantitative). The influence of the cultural beliefs and practices of mothers on the nutrition and growth of their children was explored using focus group discussions (qualitative). Narratives of mothers were used to best understand growth patterns of schoolchildren (mixed method). Data were analyzed using STATA 14 (quantitative) and Nvivo 11 (qualitative). Quantitative and qualitative data were merged for integrated mixed method analysis using a joint display analysis. Results: Mean age of children was 10 ± 2 years, ranging from 6 to 15 years. Substantial percentages of thinness (25%), underweight (24%), and stunting (22%) were observed among the children. Mothers had a mean age of 37 ± 7 years, and 75% were overweight or obese. A depressed socio-economic status indicated by a higher rate of unemployment with no income (82.3%), and dependency on social grants (86.8%) was observed. Determinants of poor growth patterns were child’s age and gender, maternal age, height and BMI, access to water supply, and refrigerator use. The narratives of mothers suggested that the children in most of their households were exposed to poverty and the inadequate intake of quality food. Conclusion: Poor growth patterns were observed among schoolchildren while their mothers were overweight or obese. Child’s gender, school grade, maternal body mass index, and access to water were the main determinants. Congruence was observed between most qualitative themes and quantitative constructs. A need for a multi sectoral approach considering an evidence based and feasible nutrition programs for schoolchildren, especially those in rural settings and educating mothers, cannot be over-emphasized.

Keywords: growth patterns, maternal factors, rural context, schoolchildren, South Africa

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Authors: Michelangelo Sofo, Giuseppe Labianca

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In recent years, the scientific community's interest in the exploratory analysis of biomedical data has increased exponentially. Considering the field of research of nutritional biologists, the curative process, based on the analysis of clinical data, is a very delicate operation due to the fact that there are multiple solutions for the management of pathologies in the food sector (for example can recall intolerances and allergies, management of cholesterol metabolism, diabetic pathologies, arterial hypertension, up to obesity and breathing and sleep problems). In this regard, in this research work a system was created capable of evaluating various dietary regimes for specific patient pathologies. The system is founded on a mathematical-numerical model and has been created tailored for the real working needs of an expert in human nutrition using the human-centered design (ISO 9241-210), therefore it is in step with continuous scientific progress in the field and evolves through the experience of managed clinical cases (machine learning process). DietAdhoc® is a decision support system nutrition specialists for patients of both sexes (from 18 years of age) developed with an agile methodology. Its task consists in drawing up the biomedical and clinical profile of the specific patient by applying two algorithmic optimization approaches on nutritional data and a symbolic solution, obtained by transforming the relational database underlying the system into a deductive database. For all three solution approaches, particular emphasis has been given to the explainability of the suggested clinical decisions through flexible and customizable user interfaces. Furthermore, the system has multiple software modules based on time series and visual analytics techniques that allow to evaluate the complete picture of the situation and the evolution of the diet assigned for specific pathologies.

Keywords: medical decision support, physiological data extraction, data driven diagnosis, human centered AI, symbiotic AI paradigm

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Authors: Sayed M. Ahmed, Sawsan S. Darwish, Nagib A. Elmarzugi, Mohammad A. Al-Dosari, Mahmoud A. Adam, Nadia A. Al-Mouallimi

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Historical stone surfaces and architectural heritage may undergo unwanted changes due to the exposure to many physical and chemical deterioration factors, the innovative properties of the nano - materials can have advantageous application in the restoration and conservation of the cultural heritage with relation to the tailoring of new products for protection and consolidation of stone. The current work evaluates the effectiveness of inorganic compatible treatments; based on nanosized particles of silica (SiO2) dispersed in silicon based product, commonly used as a water-repellent/ consolidation for the construction materials affected by different kinds of decay. The nanocomposites obtained by dispersing the silica nanoparticles in polymeric matrices SILRES® BS OH 100 (solventless mixtures of ethyl silicates), in order to obtain a new nanocomposite, with hydrophobic and consolidation properties, to improve the physical and mechanical properties of the stone material. The nanocomposites obtained and pure SILRES® BS OH 100 were applied by brush Experimental stone blocks. The efficacy of the treatments has been evaluated after consolidation and artificial Thermal aging, through capillary water absorption measurements, Ultraviolet-light exposure to evaluate photo-induced and the hydrophobic effects of the treated surface, Scanning electron microscopy (SEM) examination is performed to evaluate penetration depth, re-aggregating effects of the deposited phase and the surface morphology before and after artificialaging. Sterio microscopy investigation is performed to evaluate the resistant to the effects of the erosion, acids and salts. Improving of stone mechanical properties were evaluated by compressive strength tests, colorimetric measurements were used to evaluate the optical appearance. All the results get together with the apparent effect that, silica/polymer nanocomposite is efficient material for the consolidation of artistic and architectural sandstone monuments, completely compatible, enhanced the durability of sandstone toward thermal and UV aging. In addition, the obtained nanocomposite improved the stone mechanical properties and the resistant to the effects of the erosion, acids and salts compared to the samples treated with pure SILRES® BS OH 100 without silica nanoparticles.

Keywords: colorimetric measurements, compressive strength, nanocomposites, porous stone consolidation, silica nanoparticles, sandstone

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Authors: Claudia Cabezas-Zabala, Jairo Lindarte-Artunduaga, Carlos Mario Zuluaga-Dominguez

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Amaranth is an emerging pseudocereal rich in such essential nutrients as protein and dietary fiber, which was employed as an ingredient in the formulation of crackers to evaluate the rheological performance and sensory acceptability of the obtained food. A completely randomized factorial design was used with two factors: (A) ratio of wheat and amaranth flour used in the preparation of the dough, in proportion 90:10 and 80:20 (% w/w) and (B) two levels of inulin addition of 8.4% and 16.7 %, having two control doughs made from amaranth and wheat flour, respectively. Initially, the functional properties of the formulations mentioned were measured, showing no significant differences in the water absorption capacity (WAC) and swelling power (SP), having mean values between 1.66 and 1.81 g/g for WAC and between 1.75 and 1.86 g/g for SP, respectively. The amaranth flour had the highest water holding capacity (WHR) of 8.41 ± 0.15 g/g and emulsifying activity (EA) of 74.63 ± 1.89 g/g. Moreover, the rheological behavior, measured through the use of farinograph, extensograph, Mixolab, and falling index, showed that the formulation containing 20% of amaranth flour and 7.16% of inulin had a rheological behavior similar to the control produced exclusively with wheat flour, being the former, the one selected for the preparation of crackers. For this formulation, the farinograph showed a mixing tolerance index of 11 UB, indicating a strong and cohesive dough; likewise, the Mixolab showed dough reaches stability at 6.47 min, indicating a good resistance to mixing. On the other hand, the extensograph exhibited a dough resistance of 637 UB, as well as extensibility of 13.4 mm, which corresponds to a strong dough capable of resisting the laminate. Finally, the falling index was 318 s, which indicates the crumb will retain enough air to enhance the crispness of a characteristic cracker. Finally, a sensory consumer test did not show significant differences in the evaluation of aroma between the control and the selected formulation, while this latter had a significantly lower rating in flavor. However, a purchase intention of 70 % was observed among the population surveyed. The results obtained in this work give perspectives for the industrial use of amaranth in baked goods. Additionally, amaranth has been a product typically linked to indigenous populations in the Andean South American countries; therefore, the search for diversification and alternatives of use for this pseudocereal has an impact on the social and economic conditions of such communities. The technological versatility and nutritional quality of amaranth is an advantage for consumers, favoring the consumption of healthy products with important contributions of dietary fiber and protein.

Keywords: amaranth, crackers, rheology, pseudocereals, kneaded products

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Authors: Sasini U. G. Nanayakkara, Nishala E. Wedamulla, W. A. J. P. Wijesinghe

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Lovi (Flacourtia inermis) is an underutilized fruit crop grown in Sri Lanka with promising antioxidant properties; thus, exhibits the great potential to use as a natural antioxidant. With the concern of synthetic antioxidants, there is a growing trend towards the addition of a natural antioxidant to retard the rancidity of edible oils. Hence, in this backdrop, extract obtained from the peel of F. inermis fruit was used to retard the rancidity of selected edible oils. Free fatty acid (FFA) content and peroxide value (PV) of sunflower oil (SO) and virgin coconut oil (VCO) were measured at 3-day intervals for 21 days at 65 ± 5°C after addition of extract at 500, 1000, 2000 ppm levels and α-tocopherol at 500 ppm level was used as positive control. SO and VCO without added extract was used as the control. The extract was prepared with 70% ethanol using ultrasound-assisted extraction, and antioxidant efficacy and total phenolic content (TPC) of the extract were measured using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity and Folin-Ciocalteu method respectively. Antioxidant activity (IC50) and TPC of the extract were 227.14 ± 4.12 µgmL⁻¹ and 4.87 ± 0.01 mg GAE per gram, respectively. During the storage period, FFA content and PV of both oils were increased with time. However, SO showed comparatively high PV than that of VCO and thereby indicate the progression of lipid oxidation as PV is a good indicator of the extent of primary oxidative products formed in oils. The most effective extract concentration was 2000 ppm. After 21 days of storage, VCO (control) sample exhibited significantly (p < 0.05) high FFA (0.36%) and PV (1.93 meq kg⁻¹) than that of VCO with 1000 ppm (FFA: 0.35%; PV: 1.72 meq kg⁻¹) and 2000 ppm (FFA: 0.28%; PV: 1.19 meq kg-1) levels of extract. Thus, demonstrates the efficacy of lovi peel extract in retardation of lipid oxidation of edible oils during storage at higher concentrations of the extract addition. Moreover, FFA and PV of SO (FFA: 0.10%; PV: 12.38 meq kg⁻¹) and VCO (FFA: 0.28%; PV: 1.19 meq kg⁻¹) at 2000 ppm level of extract were significantly (p < 0.05) lower than that of positive control: SO with α-tocopherol (FFA: 0.22%, PV: 17.94 meq kg⁻¹) and VCO with α-tocopherol (FFA: 0.29%, PV: 1.39 meq kg⁻¹) after 21 days. Accordingly, lovi peel extract at 2000 ppm level was more effective than α-tocopherol in retardation of lipid oxidation of edible oils. In conclusion, lovi peel extract has strong antioxidant properties and can be used as a natural antioxidant to inhibit deteriorative oxidation of edible oils.

Keywords: antioxidant, Flacourtia inermis, peroxide value, virgin coconut oil

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Authors: Wilko Planje, Remco Pollé, Frank van Buuren

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An increased share of renewable energy sources in the built environment implies the usage of energy buffers to match supply and demand and to prevent overloads of existing grids. Compact heat storage systems based on thermochemical materials (TCM) are promising to be incorporated in future installations as an alternative for regular thermal buffers. This is due to the high energy density (1 – 2 GJ/m3). In order to determine the feasibility of TCM-based systems on building level several installation configurations are simulated and analyzed for different mixes of renewable energy sources (solar thermal, PV, wind, underground, air) for apartments/multistore-buildings for the Dutch situation. Thereby capacity, volume and financial costs are calculated. The simulation consists of options to include the current and future wind power (sea and land) and local roof-attached PV or solar-thermal systems. Thereby, the compact thermal buffer and optionally an electric battery (typically 10 kWhe) form the local storage elements for energy matching and shaving purposes. Besides, electric-driven heat pumps (air / ground) can be included for efficient heat generation in case of power-to-heat. The total local installation provides both space heating, domestic hot water as well as electricity for a specific case with low-energy apartments (annually 9 GJth + 8 GJe) in the year 2025. The energy balance is completed with grid-supplied non-renewable electricity. Taking into account the grid capacities (permanent 1 kWe/household), spatial requirements for the thermal buffer (< 2.5 m3/household) and a desired minimum of 90% share of renewable energy per household on the total consumption the wind-powered scenario results in acceptable sizes of compact thermal buffers with an energy-capacity of 4 - 5 GJth per household. This buffer is combined with a 10 kWhe battery and air source heat pump system. Compact thermal buffers of less than 1 GJ (typically volumes 0.5 - 1 m3) are possible when the installed wind-power is increased with a factor 5. In case of 15-fold of installed wind power compact heat storage devices compete with 1000 L water buffers. The conclusion is that compact heat storage systems can be of interest in the coming decades in combination with well-retrofitted low energy residences based on the current trends of installed renewable energy power.

Keywords: compact thermal storage, thermochemical material, built environment, renewable energy

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Authors: Panupong Lohrattanarungrot, Falan Srisuriyachai

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Polymer flooding is a well-known technique used for controlling mobility ratio in heterogeneous reservoirs, leading to improvement of sweep efficiency as well as wellbore profile. However, low injectivity of viscous polymer solution attenuates oil recovery rate and consecutively adds extra operating cost. An attempt of this study is to improve injectivity of polymer solution while maintaining recovery factor, enhancing effectiveness of polymer flooding method. This study is performed by using reservoir simulation program to modify conventional single polymer slug into sequential polymer flooding, emphasizing on increasing of injectivity and also reduction of polymer amount. Selection of operating conditions for single slug polymer including pre-injected water, polymer concentration and polymer slug size is firstly performed for a layered-heterogeneous reservoir with Lorenz coefficient (Lk) of 0.32. A selected single slug polymer flooding scheme is modified into sequential polymer flooding with reduction of polymer concentration in two different modes: Constant polymer mass and reduction of polymer mass. Effects of Residual Resistance Factor (RRF) is also evaluated. From simulation results, it is observed that first polymer slug with the highest concentration has the main function to buffer between displacing phase and reservoir oil. Moreover, part of polymer from this slug is also sacrificed for adsorption. Reduction of polymer concentration in the following slug prevents bypassing due to unfavorable mobility ratio. At the same time, following slugs with lower viscosity can be injected easily through formation, improving injectivity of the whole process. A sequential polymer flooding with reduction of polymer mass shows great benefit by reducing total production time and amount of polymer consumed up to 10% without any downside effect. The only advantage of using constant polymer mass is slightly increment of recovery factor (up to 1.4%) while total production time is almost the same. Increasing of residual resistance factor of polymer solution yields a benefit on mobility control by reducing effective permeability to water. Nevertheless, higher adsorption results in low injectivity, extending total production time. Modifying single polymer slug into sequence of reduced polymer concentration yields major benefits on reducing production time as well as polymer mass. With certain design of polymer flooding scheme, recovery factor can even be further increased. This study shows that application of sequential polymer flooding can be certainly applied to reservoir with high value of heterogeneity since it requires nothing complex for real implementation but just a proper design of polymer slug size and concentration.

Keywords: polymer flooding, sequential, heterogeneous reservoir, residual resistance factor

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Authors: Homayon Ahmad Panahi, Nika Shakerin, Farahnaz Zolriasatain, Elham Moniri

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In this research, poly-ethylene terephthalate granule was prepared from Tak Corporation. The granule was characterized by fourier transform infra-red spectroscopy. Then the effects of various parameters on brilliant green sorption such as pH, contact time were studied. The optimum pH value for sorption of brilliant green was 6. The sorption capacity of the granule for brilliant green was 4.6 mg g−1. The profile of brilliant green uptake on this sorbent reflects a good accessibility of the chelating sites in the poly-ethylene terephthalate granule. The developed method was utilized for the determination of brilliant green in environmental water samples by UV/Vis spectrophotometry with satisfactory results.

Keywords: poly-ethylene terephthalate granule, brilliant green, environmental sample, removal

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Authors: Thapelo Aubrey Motsieng

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Fluidized bed combustion (FBC) is a clean coal technology used in the combustion of low-grade coals for power generation. The production of large solid wastes such as bottom ashes from this process is a problem. The bottom ash contains some toxic elements which can leach out soils and contaminate surface and ground water; for this reason, they can neither be disposed of in landfills nor lagoons anymore. The production of geopolymers from bottom ash for structural and concrete applications is an option for their disposal. In this study, the waste bottom ash obtained from the combustion of three low grade South African coals in a bubbling fluidized bed reactor was used to produce geopolymers. The geopolymers were cured in a household microwave. The results showed that the microwave curing enhanced the reactivity and strength of the geopolymers.

Keywords: bottom ash, geopolymers, coal, compressive strength

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Authors: Geminne Manzano, Clairecynth Yu, Lilibeth Salvador-Reyes, Viviene Santiago, Porfirio AliñO

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The distribution and abundance patterns of many marine sessile organisms such as sponges vary among and within reefs. Determining the factors affecting its distribution is essential especially for organisms that produce secondary metabolites with pharmaceutical importance. In this study, the small-scale distribution patterns of the Philippine blue sponge, Xestospongia sp. in relation to some ecological factors were examined. The relationship between the renieramycin-M production and their benthic attributes were also determined. Ecological surveys were conducted on two stations with varying depth and exposure located in Oriental Mindoro, Philippines. Three 30 by 6m belt transect were used to assess the sponge abundance at each station. The substratum of the sponges was also characterized. Fish visual census observations were also taken together with the photo transect methods benthic surveys. Sponge samples were also collected for the extraction of Renieramycin-M and for further chemical analysis. Varying distribution patterns were observed to be attributed to the combination of different ecological and environmental factors. The amount of Renieramycin-production also varied in each station. The common substratum for blue sponges includes hard and soft corals, as well as, dead coral with algal patches. Blue sponges from exposed habitat frequently grow associated with massive and branching corals, Porites sp., while the most frequent substrate found on sheltered habitats is the coral Pavona sp. Exploring the influence of ecological and environmental parameters on the abundance and distribution of sponge assemblages provide ecological insights and their potential applications to pharmaceutical studies. The results of this study provide further impetus in pursuing studies into patterns and processes of the Philippine blue sponge, Xestospongia sp. distribution in relation to the chemical ecology of its secondary metabolites.

Keywords: distribution patterns, Porifera, Renieramycin-M, sponge assemblages, Xestospongia sp.

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Authors: Laura Victoria Vigoya Morales, David Rolando Suarez Mora

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The problem of detecting enterococcus faecalis is receiving considerable attention with the new cases of beachgoers infected with the bacteria, which can be found in fecal matter. The process detection of this kind of bacteria would be taking a long time, which waste time and money as a result of closing recreation place, like beach or pools. Hence, new methods for automating the process of detecting and recognition of this bacteria has become in a challenge. This article describes a novel approach to detect the enterococcus faecalis bacteria in water by using an octave algorithm, which embody a network neural. This document shows result of performance, quality and integrity of the algorithm.

Keywords: Enterococcus faecalis, image treatment, octave and network neuronal

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Authors: Yuan-Hao Lee, Chia-Wei Lee, Ming-Fang Lin, Tzu-Huei Wu, Chih-Hsiang Ko, Wing P. Chan

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Computed tomography (CT) scan of the head is a good method for investigating cranial lesions. However, radiation-induced oxidative stress can be accumulated in the eyes and promote carcinogenesis and cataract. In this regard, we aimed to protect the eyes with barium sulfate shield(s) during CT scans and investigate the resultant image quality and radiation dose to the eye. Patients who underwent health examinations were selectively enrolled in this study in compliance with the protocol approved by the Ethics Committee of the Joint Institutional Review Board at Taipei Medical University. Participants’ brains were scanned with a water-based marker simultaneously by a multislice CT scanner (SOMATON Definition Flash) under a fixed tube current-time setting or automatic tube current modulation (TCM). The lens dose was measured by Gafchromic films, whose dose response curve was previously fitted using thermoluminescent dosimeters, with or without barium sulfate or bismuth-antimony shield laid above. For the assessment of image quality CT images at slice planes that exhibit the interested regions on the zygomatic, orbital and nasal bones of the head phantom as well as the water-based marker were used for calculating the signal-to-noise and contrast-to-noise ratios. The application of barium sulfate and bismuth-antimony shields decreased 24% and 47% of the lens dose on average, respectively. Under topogram-based TCM, the dose saving power of bismuth-antimony shield was mitigated whereas that of barium sulfate shield was enhanced. On the other hand, the signal-to-noise and contrast-to-noise ratios of DSCT images were decreased separately by barium sulfate and bismuth-antimony shield, resulting in an overall reduction of the CNR. In contrast, the integration of topogram-based TCM elevated signal difference between the ROIs on the zygomatic bones and eyeballs while preferentially decreasing the signal-to-noise ratios upon the use of barium sulfate shield. The results of this study indicate that the balance between eye exposure and image quality can be optimized by combining eye shields with topogram-based TCM on the multislice scanner. Eye shielding could change the photon attenuation characteristics of tissues that are close to the shield. The application of both shields on eye protection hence is not recommended for seeking intraorbital lesions.

Keywords: computed tomography, barium sulfate shield, dose saving, image quality

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Authors: Marjan Moradi Fard, Hossein Rassi, Masoud Houshmand

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Aim: Breast cancer is one of the most common cancers affecting the morbidity and mortality of Iranian women. This disease is a result of collective alterations of oncogenes and tumor suppressor genes. Studies have produced conflicting results concerning the role of p53 codon 72 polymorphism (G>C) and miR-146a rs2910164 polymorphism (G>C) on the risk of several cancers; therefore, a research was performed to estimate the association between the p53 codon 72 polymorphism and miR-146a rs2910164 polymorphism in breast cancer. Methods and Materials: A total of 45 archival breast cancer samples from khatam hospital and 40 healthy samples were collected. Verification of each cancer reported in a relative was sought through the pathology reports of the hospital records. Then, DNA extracted from all samples by standard methods and p53 codon 72 polymorphism genotypes and miR-146a rs2910164 polymorphism genotypes were analyzed using multiplex PCR. The tubules, mitotic activity, necrosis, polymorphism and grade of breast cancer were staged by Nottingham histological grading and immunohistochemical staining of the sections from the paraffin wax embedded tissues for the expression of ER, PR and p53 was carried out using a standard method. Finally, data analysis was performed using the 7 version of the Epi Info(TM) 2012 software and test chi-square(x2) for trend. Results: Successful DNA extraction was assessed by PCR amplification of b-actin gene (99 bp). According to the results, p53 GG genotype and miR-146a rs2910164 CC genotype was significantly associated with increased risk of breast cancer in the study population. In this study, we established that tumors of p53 GG genotype and miR-146a rs2910164 CC genotype exhibited higher mitotic activity, higher polymorphism, lower necrosis, lower tubules, higher ER- and PR-negatives and lower TP53-positives than the other genotypes. Conclusion: The present study provided preliminary evidence that a p53 GG genotype may effect breast cancer risk in the study population, interacting synergistically with miR-146a rs2910164 CC genotype. Our results demonstrate that the testing of p53 codon 72 polymorphism genotypes and miR-146a rs2910164 polymorphism genotypes in combination with clinical parameters can serve as major risk factors in the early identification of breast cancers.

Keywords: breast cancer, p53 codon 72 polymorphism, miR-146a rs2910164 polymorphism, genotypes

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Authors: A. Benhadji, M. Taleb Ahmed

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Among the various methods of treatment, advanced oxidation processes (AOP) are the most promising ones. In this study, Peroxi Electrocoagulation Process (PEP) was investigated for the treatment of detergent wastewater. The process was compared with electrooxidation treatment. The results showed that chemical oxygen demand (COD) was high 7584 mgO₂.L^-1, while the biochemical oxygen demand was low (250 mgO₂.L^-1). This wastewater was hardly biodegradable. Electrochemical process was carried out for the removal of detergent using a glass reactor with a volume of 1 L and fitted with three electrodes. A direct current (DC) supply was used. Samples were taken at various current density (0.0227 A/cm² to 0.0378 A/cm²) and reaction time (1-2-3-4 and 5 hour). Finally, the COD was determined. The results indicated that COD removal efficiency of PEP was observed to increase with current intensity and reached to 77% after 5 h. The highest removal efficiency was observed after 5 h of treatment.

Keywords: AOP, COD, detergent, PEP, wastewater

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Authors: Guannan Ren, Thomas Mazzuchi, Shahram Sarkani

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Electric vehicle battery recycling has emerged as a critical process in the transition toward sustainable transportation. As the demand for electric vehicles continues to rise, so does the need to address the end-of-life management of their batteries. Electric vehicle battery recycling benefits resource recovery and supply chain stability by reclaiming valuable metals like lithium, cobalt, nickel, and graphite. The reclaimed materials can then be reintroduced into the battery manufacturing process, reducing the reliance on raw material extraction and the environmental impacts of waste. Current battery recycling rates are insufficient to meet the growing demands for raw materials. While significant progress has been made in electric vehicle battery recycling, many areas can still improve. Standardization of battery designs, increased collection and recycling infrastructures, and improved efficiency in recycling processes are essential for scaling up recycling efforts and maximizing material recovery. This work delves into key factors, such as regulatory frameworks, economic incentives, and technological processes, that influence the cost-effectiveness and efficiency of battery recycling systems. A system dynamics model that considers variables such as battery production rates, demand and price fluctuations, recycling infrastructure capacity, and the effectiveness of recycling processes is created to study how these variables are interconnected, forming feedback loops that affect the overall supply chain efficiency. Such a model can also help simulate the effects of stricter regulations on battery disposal, incentives for recycling, or investments in research and development for battery designs and advanced recycling technologies. By using the developed model, policymakers, industry stakeholders, and researchers may gain insights into the effects of applying different policies or process updates on electric vehicle battery recycling rates.

Keywords: environmental engineering, modeling and simulation, circular economy, sustainability, transportation science, policy

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Authors: Amanina Iymia Jeffree, Reena Thriumani, Mohammad Iqbal Omar, Ammar Zakaria, Yumi Zuhanis Has-Yun Hashim, Ali Yeon Md Shakaff

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Metabolite profiling is a strategy to be approached in the pattern recognition method focused on three types of cancer cell line that driving the most to death specifically lung, breast, and colon cancer. The purpose of this study was to discriminate the VOCs pattern among cancerous and control group based on metabolite profiling. The sampling was executed utilizing the cell culture technique. All culture flasks were incubated till 72 hours and data collection started after 24 hours. Every running sample took 24 minutes to be completed accordingly. The comparative metabolite patterns were identified by the implementation of headspace-solid phase micro-extraction (HS-SPME) sampling coupled with gas chromatography-mass spectrometry (GCMS). The optimizations of the main experimental variables such as oven temperature and time were evaluated by response surface methodology (RSM) to get the optimal condition. Volatiles were acknowledged through the National Institute of Standards and Technology (NIST) mass spectral database and retention time libraries. To improve the reliability of significance, it is of crucial importance to eliminate background noise which data from 3rd minutes to 17th minutes were selected for statistical analysis. Targeted metabolites, of which were annotated as known compounds with the peak area greater than 0.5 percent were highlighted and subsequently treated statistically. Volatiles produced contain hundreds to thousands of compounds; therefore, it will be optimized by chemometric analysis, such as principal component analysis (PCA) as a preliminary analysis before subjected to a pattern classifier for identification of VOC samples. The volatile organic compound profiling has shown to be significantly distinguished among cancerous and control group based on metabolite profiling.

Keywords: in vitro cancer cell line, metabolite profiling, pattern recognition, volatile organic compounds

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Authors: Emmanuelle Merat, Arnaud Aubert, Sophie Cambos, Francis Vial, Patrick Beau

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Basically, consumers are sensitive to many stimuli when applying a cream: brand, packaging and indeed formulation compositions. Many studies demonstrated the influence of some stimuli such as brand, packaging, formula color and odor (e.g. in make-up applications). Those parameters influence perceived quality of the product. The objective of this work is to further investigate the relationship between nude skincare basic compositions with different textures and consumer experience. A tentative final step will be to connect the consumer feelings with key ingredients in the compositions. A new approach was developed to better understand touch-related subjective experience in consumers based on a combination of methods: sensory analysis with ten experts, preference mapping on one hundred female consumers and emotional assessments on thirty consumers (verbal and non-verbal through prosody and gesture monitoring). Finally, a methodology based on ‘sensorial trip’ (after olfactory, haptic and musical stimuli) has been experimented on the most interesting textures with 10 consumers. The results showed more or less impact depending on compositions and also on key ingredients. Three types of formulation particularly attracted the consumer: an aqueous gel, an oil-in-water emulsion, and a patented gel-in-oil formulation type. Regarding these three formulas, the preferences were both revealed through sensory and emotion tests. One was recognized as the most innovative in consumer sensory test whereas the two other formulas were discriminated in emotions evaluation. The positive emotions were highlighted especially in prosody criteria. The non-verbal analysis, which corresponds to the physical parameters of the voice, showed high pitch and amplitude values; linked to positive emotions. Verbatim, verbal content of responses (i.e., ideas, concepts, mental images), confirmed the first conclusion. On the formulas selected for their positive emotions generation, the ‘sensorial trip’ provided complementary information to characterize each emotional profile. In the second step, dedicated to better understand ingredients power, two types of ingredients demonstrated an obvious input on consumer preference: rheology modifiers and emollients. As a conclusion, nude cosmetic compositions with well-chosen textures and ingredients can positively stimulate consumer emotions contributing to capture their preference. For a complete achievement of the study, a global approach (Asia, America territories...) should be developed.

Keywords: sensory, emotion, cosmetic formulations, ingredients' influence

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Authors: Mohammad Asadpour

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Cryptosporidium spp. is zoonotic pathogens transmissible from a variety of animals to humans and is a considerable public health concern. Calves have been identified in numerous reports as a major source of environmental contamination with this pathogen. Parasite has a different species that are the cases of zoonotic disease in immunodeficient people and neonatal calves. Cryptosporidium oocysts are extremely resistant to chlorine and other physical cases that commonly used in drinking water. Reproduction of resistant oocytes is a way for this monoxenous parasite to remain in the environment. Cryptosporidium parvum is the most important species that has human and cattle genotypes. Cryptosporidium is one of the most important causes of diarrhea in neonatal calves and also, one of the four causes of diarrhea symptoms in pre-weaned calves. Because of the incompetent immune system in calves, Cryptosporidium infection is the cause of a lot of problems in raising farms.

Keywords: Cryptosporidium spp, dairy calves, importance, veterinary medicine

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Authors: Yves Lacroix, Van Van Than, Didier Léandri, Pierre Liardet

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The tombolo of Giens is located in the town of Hyères (France). We recall the history of coastal erosion, and prominent factors affecting the evolution of the western tombolo. We then discuss the possibility of stabilizing the western tombolo. Our argumentation relies on a coupled model integrating swells, currents, water levels and sediment transport. We present the conclusions of the simulations of various scenarios, including pre-existing propositions from coastal engineering offices. We conclude that beach replenishment seems to be necessary but not sufficient for the stabilization of the beach. Breakwaters reveal effective particularly in the most exposed northern area. Some solutions fulfill conditions so as to be elected as satisfactory. We give a comparative analysis of the efficiency of 14 alternatives for the protection of the tombolo.

Keywords: breakwaters, coupled models, replenishment, silting

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Authors: Stefan Peters, Phillip Roetman

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The global loss of biodiversity is threatening the benefits nature provides to human populations and has become a more pressing issue than climate change and requires immediate attention. While there have been successful global agreements for environmental protection, such as the Montreal Protocol, these are rare, and we cannot rely on them solely. Thus, it is crucial to take national and local actions to support biodiversity. Australia is one of the 17 countries in the world with a high level of biodiversity, and its cities are vital habitats for endangered species, with more of them found in urban areas than in non-urban ones. However, the protection of biodiversity in metropolitan Adelaide has been inadequate, with over 130 species disappearing since European colonization in 1836. In this research project we conceptualized, developed and implemented a framework for wildlife Habitat Hotspots and Habitat Corridor modelling in an urban context using geographic data and GIS modelling and analysis. We used detailed topographic and other geographic data provided by a local council, including spatial and attributive properties of trees, parcels, water features, vegetated areas, roads, verges, traffic, and census data. Weighted factors considered in our raster-based Habitat Hotspot model include parcel size, parcel shape, population density, canopy cover, habitat quality and proximity to habitats and water features. Weighted factors considered in our raster-based Habitat Corridor model include habitat potential (resulting from the Habitat Hotspot model), verge size, road hierarchy, road widths, human density, and presence of remnant indigenous vegetation species. We developed a GIS model, using Python scripting and ArcGIS-Pro Model-Builder, to establish an automated reproducible and adjustable geoprocessing workflow, adaptable to any study area of interest. Our habitat hotspot and corridor modelling framework allow to determine and map existing habitat hotspots and wildlife habitat corridors. Our research had been applied to the study case of Burnside, a local council in Adelaide, Australia, which encompass an area of 30 km2. We applied end-user expertise-based category weightings to refine our models and optimize the use of our habitat map outputs towards informing local strategic decision-making.

Keywords: biodiversity, GIS modeling, habitat hotspot, wildlife corridor

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Authors: Mohamed El-Bady

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The Northern Egyptian Lagoons are (from east to west) Bardawil Lagoon, Manzala Lagoon, Burullus Lagoon, Edku Lagoons and Mariute Lagoon. These lagoons have been received the bulk of drainage water from the lands of Delta and from the other coastal areas. Where, the heavy metals can occur in Lagoons environments through a variety of sources, including industries, wastewaters and domestic effluents. The potential ecological risk index (RI) calculation of the bottom sediments of the northern lagoons depends on contamination factor (CF), potential ecological risk factor and proposed toxic response factor (Tr). Each lagoon with special indices according to its conditions.

Keywords: Northern Lagoons, Nile Delta, ecological risk index, contamination factor

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Authors: Nathaporn Areerachakul

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In this study, the adsorption capacity of GAC with metsulfuron methyl was evaluated by using adsorption equilibrium and a fixed bed. Mathematical modelling was also used to simulate the GAC adsorption behavior. Adsorption equilibrium experiment of GAC was conducted using a constant concentration of metsulfuron methyl of 10 mg/L. The purpose of this study was to find the single component equilibrium concentration of herbicide. The adsorption behavior was simulated using the Langmuir, Freundlich, and Sips isotherm. The Sips isotherm fitted the experimental data reasonably well with an error of 6.6 % compared with 15.72 % and 7.07% for the Langmuir isotherm and Freudrich isotherm. Modelling using GAC adsorption theory could not replicate the experimental results in fixed bed column of 10 and 15 cm bed depths after a period more than 10 days of operation. This phenomenon is attributed to the formation of micro-organism (BAC) on the surface of GAC in addition to GAC alone.

Keywords: isotherm, adsorption equilibrium, GAC, metsulfuron methyl

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Authors: Rasha Al-Saedi, Anthony Meijer

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The progress of new porous materials has increased rapidly over the past decade for use in applications such as catalysis, gas storage and removal of environmentally unfriendly species due to their high surface area and high thermal stability. In this work, a theoretical study of the zirconium-based metal organic framework (MOFs) were examined in order to determine their potential for gas adsorption of various guest molecules: CO2, N2, CH4 and H2. The zirconium cluster consists of an inner Zr6O4(OH)4 core in which the triangular faces of the Zr6- octahedron are alternatively capped by O and OH groups which bound to nine formate groups and three benzoate groups linkers. General formula is [Zr(μ-O)4(μ-OH)4(HCOO)9((phyO2C)3X))] where X= CH2OH, CH2NH2, CH2CONH2, n(NH2); (n = 1-3). Three types of adsorption sites on the Zr metal center have been studied, named according to capped chemical groups as the ‘−O site’; the H of (μ-OH) site removed and added to (μ-O) site, ‘–OH site’; (μ-OH) site removed, the ‘void site’ where H2O molecule removed; (μ-OH) from one site and H from other (μ-OH) site, in addition to no defect versions. A series of investigations have been performed aiming to address this important issue. First, density functional theory DFT-B3LYP method with 6-311G(d,p) basis set was employed using Gaussian 09 package in order to evaluate the gas adsorption performance of missing-linker defects in zirconium cluster. Next, study the gas adsorption behaviour on different functionalised zirconium clusters. Those functional groups as mentioned above include: amines, alcohol, amide, in comparison with non-substitution clusters. Then, dispersion-corrected density functional theory (DFT-D) calculations were performed to further understand the enhanced gas binding on zirconium clusters. Finally, study the water effect on CO2 and N2 adsorption. The small functionalized Zr clusters were found to result in good CO2 adsorption over N2, CH4, and H2 due to the quadrupole moment of CO2 while N2, CH4 and H2 weakly polar or non-polar. The adsorption efficiency was determined using the dispersion method where the adsorption binding improved as most of the interactions, for example, van der Waals interactions are missing with the conventional DFT method. The calculated gas binding strengths on the no defect site are higher than those on the −O site, −OH site and the void site, this difference is especially notable for CO2. It has been stated that the enhanced affinity of CO2 of no defect versions is most likely due to the electrostatic interactions between the negatively charged O of CO2 and the positively charged H of (μ-OH) metal site. The uptake of the gas molecule does not enhance in presence of water as the latter binds to Zr clusters more strongly than gas species which attributed to the competition on adsorption sites.

Keywords: density functional theory, gas adsorption, metal- organic frameworks, molecular simulation, porous materials, theoretical chemistry

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