Search results for: stage composition
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5891

Search results for: stage composition

2261 Screening of the Sunflower Genotypes for Drought Stress at Seedling Stage by Polyethylene Glycol under Laboratory Conditions

Authors: Uzma Ayaz, Sanam Bashir, Shahid Iqbal Awan, Muhammad Ilyas, Muhammad Fareed Khan

Abstract:

Drought stress directly affects growth along with the productivity of plants by altering plant water status. Sunflower (Helianthus annuus L.), an oilseed crop, is adversely affected by abiotic stresses. The present study was carried out to characterize the genetic variability for seedling and morpho-physiological parameters in different sunflower genotypes under water-stressed conditions. A total of twenty-seven genotypes, including two hybrids, eight advanced lines and seventeen accessions of sunflower (Helianthus annuus L.) were tested against drought stress at Seedling stages by Polyethylene glycol (PEG). Significant means were calculated among traits using analysis of variance (ANOVA) whereas, correlation and principal component analysis also confirmed that germination percentage, root length, shoot length, chlorophyll content, stomatal frequency are positively linked with each other hence, these traits were responsible for most of the variation among genotypes. The cluster analysis results showed that genotypes Ausun, line-3, line-2, and 17578, line-1, line-7, line-6 and 17562 as more diverse among all the genotypes. These most divergent genotypes could be utilized in the development of drought-tolerant inbreed lines which could be subsequently used in future heterosis breeding programs.

Keywords: sunflower, drought, stress, polyethylene- glycol, screening

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2260 Oxygen-Tolerant H₂O₂ Reduction Catalysis by Iron Phosphate Coated Iron Oxides

Authors: Chia-Ting Chang, Chia-Yu Lin

Abstract:

We report on the decisive role of iron phosphate (FePO₄), formed in-situ during the electrochemical characterization, played in the electrocatalytic activity, especially its oxygen tolerance of iron oxides towards H₂O₂ reduction. Iron oxides studied including, Nanorod arrays (NRs) of β-FeOOH, γ-Fe₂O₃, α-Fe₂O₃, α-Fe₂O₃ nanosheets (α-Fe₂O₃NS), α-Fe₂O₃ nanoparticles (α-Fe₂O₃NP), were synthesized using chemical bath deposition. The nanostructure was controlled simply by adjusting the composition of precursor solution and reaction duration for CBD process, whereas the crystal phase was controlled by adjusting the annealing temperature. It was found that iron phosphate (FePO₄) was deposited in-situ onto the surface of this nanostructured α-Fe₂O₃ during the electrochemical pretreatment in the phosphate electrolyte, and both FePO₄ and α-Fe₂O₃ showed the activity in catalysing the electrochemical reduction of H₂O₂. In addition, the interaction/compatibility between deposited FePO₄ and iron oxides has a decisive effect on the overall electrocatalytic activity of the resultant electrodes; FePO₄ only showed synergetic effect on the overall electrocatalytic activity of α-Fe₂O₃NR and α-Fe2O₃NS. Both α-Fe₂O₃NR and α-Fe₂O₃NS showed two reduction peaks in phosphate electrolyte containing H₂O₂, one being pH-dependent and related to the electrocatalytic properties of FePO₄, and the other one being pH-independent and only related to the intrinsic electrocatalytic properties of α-Fe₂O₃NR and α-Fe₂O₃NS. However, all iron oxides showed only one pH-independent reductive peak in non-phosphate electrolyte containing H₂O₂. The synergesitic catalysis exerted by FePO₄ with α-Fe₂O₃NR or α-Fe₂O₃NS providing additional oxygen-insensitive active site for H₂O₂ reduction, which allows their applications to electrochemical detection of H₂O₂ without the interference of O₂ involving in oxidase-catalyzed chemical processes.

Keywords: H₂O₂ reduction, Iron oxide, iron phosphate, O₂ tolerance

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2259 Pharmacological Activities and Potential Uses of Cyperus Rotundus: A Review

Authors: Arslan Masood Pirzada, Muhammad Naeem, Hafiz Haider Ali, Muhammad Latif, Aown Sammar Raza, Asad Hussain Bukhari, Muhammad Saqib, Muhammad Ijaz

Abstract:

Cyperus rotundus (Cyperaceae), a medicinal herb, is being traditionally used as a home remedy for the treatment of various clinical conditions like diarrhea, diabetic, pyretic, inflammation, malaria, and for treating stomach and bowel disorders. Its current status is one of the most widespread, troublesome, and economically damaging agronomic weeds, growing wildly in various tropical and sub-tropical regions of the world. Tuber and rhizomes of Cyperus rotundus possess a higher concentration of active ingredients in the form of essential oils, phenolic acids, ascorbic acids and flavonoids, responsible for its remedial properties. Exploitation of any medicinal plant application depends on the crucial and comprehensive information about the therapeutic potential of a plant. Researchers have evaluated and characterized the significance of Cyperus rotundus as an anti-androgenic, anti-bacterial, anti-cancerous, anti-convulsant, anti-diabetic, anti-diarrheal, anti-genotoxic, anti-inflammatory, anti-lipidemic, anti-malarial, anti-mutagenic, anti-obesity, anti-oxidant, anti-uropathogenic, hepato-, cardio-, neuroprotective, and nootropic agent. This paper comprises a broad review to summarize the current state of knowledge about chemical constituents, potential economic uses and therapeutic aspects of Cyperus rotundus that will aid in the development of bioethanol and modern herbal medicine through latest technologies that will promote the ability of this plant in the cure of many clinical disorders.

Keywords: purple nutsedge, chemical composition, economic uses, therapeutic values, future directions

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2258 Music of a Film City: Interwar Europe in Los Angeles, 1930s

Authors: Alexander Rosenblatt

Abstract:

The musical culture of the city of Los Angeles, as it is seen today, developed not without the influence of outstanding musicians who came from Europe during the period between the world wars. The combination of European modernist ideas with American musical culture, which differed in many ways from European musical culture, led to unique results. During the 1920s and even more so in the 1930s, members of the Austrian-German artistic intelligentsia, particularly those of Jewish origin who felt insecure in their homeland, began to look for a safer place. The United States has become such a place for many, and many of them chose the second largest metropolis—Los Angeles. The most notable figure in this group was the modernist composer Arnold Schoenberg. Other famous musicians were conductors Otto Klemperer and Bruno Walter. The study focused on how these people acclimated to a city whose culture and business revolved around film production; what place the conductors Klemperer and Walter occupied in the city, state, and country; how Schoenberg, whose musical style was little understood by the American public, was able to realize himself; what path he took when he was accepted to two universities as a professor of counterpoint and composition; and whether he revised his own views on the development of Western music. Another aspect was the study of how the composer’s memory was preserved in the universities where he taught. The study is based primarily on materials found in four libraries of two universities located in Los Angeles, UCLA and USC, during my tenure as a visiting scholar at USC Thornton School of Music (August 2023), to be completed during my upcoming visit there in August-September 2024, as well as on interviews with people active in efforts to keep Schoenberg’s memory alive on the USC Campus.

Keywords: los angeles, filmmaking, immigrant musicians, arnold schoenberg, otto klemperer, bruno walter

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2257 Preserving Urban Cultural Heritage with Deep Learning: Color Planning for Japanese Merchant Towns

Authors: Dongqi Li, Yunjia Huang, Tomo Inoue, Kohei Inoue

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With urbanization, urban cultural heritage is facing the impact and destruction of modernization and urbanization. Many historical areas are losing their historical information and regional cultural characteristics, so it is necessary to carry out systematic color planning for historical areas in conservation. As an early focus on urban color planning, Japan has a systematic approach to urban color planning. Hence, this paper selects five merchant towns from the category of important traditional building preservation areas in Japan as the subject of this study to explore the color structure and emotion of this type of historic area. First, the image semantic segmentation method identifies the buildings, roads, and landscape environments. Their color data were extracted for color composition and emotion analysis to summarize their common features. Second, the obtained Internet evaluations were extracted by natural language processing for keyword extraction. The correlation analysis of the color structure and keywords provides a valuable reference for conservation decisions for this historic area in the town. This paper also combines the color structure and Internet evaluation results with generative adversarial networks to generate predicted images of color structure improvements and color improvement schemes. The methods and conclusions of this paper can provide new ideas for the digital management of environmental colors in historic districts and provide a valuable reference for the inheritance of local traditional culture.

Keywords: historic districts, color planning, semantic segmentation, natural language processing

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2256 Smoking Elevates the Risk of Dysbiosis Associated with Dental Decay

Authors: Razia Hossaini, Maryam Hosseini

Abstract:

Background and Objective: The impact of smoking on the shift in oral microbial composition has been questioned. This study aims to compare the oral microbiome between Turkish patients with dental caries and healthy individuals. Materials and Methods: An observational case-control study was conducted from January to June 2024, involving 270 young adults (180 with dental caries and 90 healthy controls). Participants were matched by age, gender, education, sugar consumption, and tooth-brushing habits. Oral samples were collected using sterilized swabs and preserved in a PBS-glycerol solution. Biochemical testing included culturing samples on various media and performing tests to identify bacterial species. The association of smoking with oral health was examined, and the smoking-related shift in oral microbiota was assessed statistically. Results: The study found that smoking was significantly associated with dental caries, with smokers being 1.28 times more likely to develop caries compared to non-smokers (p=0.04). Regarding oral microbiota, patients with dental caries showed a higher frequency of Escherichia coli, Pseudomonas aeruginosa, Actinobacteria, Streptococcus mutans, Streptococcus sobrinus, Lactobacillus acidophilus, and Streptococcus viridans (p ≤ 0.01). Conversely, Neisseria sp. and Micrococcus luteus were less frequently observed in patients compared to healthy controls (p ≤ 0.02). Other bacteria, such as Staphylococcus aureus, Staphylococcus epidermidis, and Lactobacillus, were more common in patients, although this was not statistically significant. Conclusion: Smoking significantly impacts oral health by promoting dysbiosis, increasing cariogenic bacteria, and reducing beneficial bacteria, which contributes to the development of dental caries.

Keywords: smoking, dysbiosis, bacteria, oral health, dental decay.

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2255 Correlation between Microalbuminuria and Hypertension in Type 2 Diabetic Patients

Authors: Alia Ali, Azeem Taj, Muhammed Joher Amin, Farrukh Iqbal, Zafar Iqbal

Abstract:

Background: Hypertension is commonly found in patients with Diabetic Kidney Disease (DKD). Microalbuminuria is the first clinical sign of involvement of kidneys in patients with type 2 diabetes. Uncontrolled hypertension induces a higher risk of cardiovascular events, including death, increasing proteinuria and progression to kidney disease. Objectives: To determine the correlation between microalbuminuria and hypertension and their association with other risk factors in type 2 diabetic patients. Methods: One hundred and thirteen type 2 diabetic patients were screened for microalbuminuria and raised blood pressure, attending the diabetic clinic of Shaikh Zayed Hospital, Lahore, Pakistan. The study was conducted from November 2012 to June 2013. Results: Patients were divided into two groups. Group 1, those with normoalbuminuria (n=63) and Group 2, those having microalbuminuria (n=50). Group 2 patients showed higher blood pressure values as compared to Group 1. The results were statistically significant and showed poor glycemic control as a contributing risk factor. Conclusion: The study concluded that there is high frequency of hypertension among type 2 diabetics but still much higher among those having microalbuminuria. So, early recognition of renal dysfunction through detection of microalbuminuria and to start treatment without any delay will confer future protection from end-stage renal disease as well as hypertension and its complications in type 2 diabetic patients.

Keywords: hypertension, microalbuminuria, diabetic kidney disease, type 2 Diabetes mellitus

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2254 Development and Evaluation of New Complementary Food from Maize, Soya Bean and Moringa for Young Children

Authors: Berhan Fikru

Abstract:

The objective of this study was to develop new complementary food from maize, soybean and moringa for young children. The complementary foods were formulated with linear programming (LP Nutri-survey software) and Faffa (corn soya blend) use as control. Analysis were made for formulated blends and compared with the control and recommended daily intake (RDI). Three complementary foods composed of maize, soya bean, moringa and sugar with ratio of 65:20:15:0, 55:25:15:5 and 65:20:10:5 for blend 1, 2 and 3, respectively. The blends were formulated based on the protein, energy, mineral (iron, zinc an calcium) and vitamin (vitamin A and C) content of foods. The overall results indicated that nutrient content of faffa (control) was 16.32 % protein, 422.31 kcal energy, 64.47 mg calcium, 3.8 mg iron, 1.87mg zinc, 0.19 mg vitamin A and 1.19 vitamin C; blend 1 had 17.16 % protein, 429.84 kcal energy, 330.40 mg calcium, 6.19 mg iron, 1.62 mg zinc, 6.33 mg vitamin A and 4.05 mg vitamin C; blend 2 had 20.26 % protein, 418.79 kcal energy, 417.44 mg calcium, 9.26 mg iron, 2.16 mg zinc, 8.43 mg vitamin A and 4.19 mg vitamin C whereas blend 3 exhibited 16.44 % protein, 417.42 kcal energy, 242.4 mg calcium, 7.09 mg iron, 2.22 mg zinc, 3.69 mg vitamin A and 4.72 mg vitamin C, respectively. The difference was found between all means statically significance (P < 0.05). Sensory evaluation showed that the faffa control and blend 3 were preferred by semi-trained panelists. Blend 3 had better in terms of its mineral and vitamin content than FAFFA corn soya blend and comparable with WFP proprietary products CSB+, CSB++ and fulfills the WHO recommendation for protein, energy and calcium. The suggested formulation with Moringa powder can therefore be used as a complementary food to improve the nutritional status and also help solve problems associated with protein energy and micronutrient malnutrition for young children in developing countries, particularly in Ethiopia.

Keywords: corn soya blend, proximate composition, micronutrient, mineral chelating agents, complementary foods

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2253 Evaluation of the Ability of COVID-19 Infected Sera to Induce Netosis Using an Ex-Vivo NETosis Monitoring Tool

Authors: Constant Gillot, Pauline Michaux, Julien Favresse, Jean-Michel Dogné, Jonathan Douxfils

Abstract:

Introduction: NETosis has emerged as a crucial yet paradoxical factor in severe COVID-19 cases. While neutrophil extracellular traps (NETs) help contain and eliminate viral particles, excessive NET formation can lead to hyperinflammation, exacerbating tissue damage and acute respiratory distress syndrome (ARDS). Aims: This study evaluates the relationship between COVID-19-infected sera and NETosis using an ex-vivo model. Methods: Sera from 8 post-admission COVID-19 patients, after receiving corticoid therapy, were used to induce NETosis in neutrophils from a healthy donor. NET formation was tracked using fluorescent markers for DNA and neutrophil elastase (NE) every 2 minutes for 8 hours. The results were expressed as a percentage of DNA/NE released over time. Key metrics, including T50 (time to 50% release) and AUC (area under the curve), representing total NETosis potential), were calculated. A 27-cytokine screening kit was used to assess the cytokine composition of the sera. Results: COVID-19 sera induced NETosis based on their cytokine profile. The AUC of NE and DNA release decreased with time following corticoid therapy, showing a significant reduction in 6 of the 8 patients (p<0.05). T50 also decreased in parallel with AUC for both markers. Cytokines concentration decrease with time after therapy administration. There is correlation between 14 cytokines concentration and NE release. Conclusion: This ex-vivo model successfully demonstrated the induction of NETosis by COVID-19 sera using two markers. A clear decrease in NETosis potential was observed over time with glucocorticoid therapy. This model can be a valuable tool for monitoring NETosis and investigating potential NETosis inducers and inhibitors.

Keywords: NETosis, COVID-19, cytokine storm, biomarkers

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2252 Endometrioma Ethanol Sclerotherapy

Authors: Lamia Bensissaid

Abstract:

Goals: Endometriosis affects 6 to 10% of women of childbearing age. 17 to 44% of them have ovarian endometriomas. Medical and surgical treatments represent the two therapeutic axes with which PMA can be associated. Laparoscopic intraperitoneal ovarian cystectomy is described as the reference technique in the management of endometriomas by learned societies (CNGOF, ESHRE, NICE). However, it leads to a significant short-term reduction in the AMH level and the number of antral follicles, especially in cases of bilateral cystectomy, large cyst size or cystectomy after recurrence. Often, the disease is at an advanced stage with several surgical patients. Most have adhesions, which increase the risk of surgical complications and suboptimal resection and, therefore recurrence of the cyst. These results led to a change of opinion towards a conservative approach. Sclerotherapy is an old technique which acts by fibrinoid necrosis. It consists of injecting a sclerosing agent into the cyst cavity. Results : Recurrence was less than 15% for a 12-month follow-up; these rates are comparable to those of surgery. It does not seem to have a negative impact on ovarian reserve, but this is not sufficiently evaluated. It has an advantage in IVF pregnancy rates compared to cystectomy, particularly in cases of recurrent endometriomas. It has the advantages: · To be done on an outpatient basis. · To be inexpensive. · To avoid sometimes difficult and iterative surgery: · To allow an increase in pregnancy rates and the preservation of the ovarian reserve compared to iterative surgery. · of great interest in cases of bilateral endometriomas (kissing ovaries) or recurrent endometriomas. Conclusions: Ethanol sclerotherapy could be a good alternative to surgery.

Keywords: Endometrioma, Sclerotherapy, infertility, Ethanol

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2251 The Role of Inflammasomes for aβ Microglia Phagocytosis in Alzheimer Disease

Authors: Francesca La Rosa , Marina Saresella, Mario Clerici, Michael Heneka

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Neuroinflammation plays a key role in the modulation of the pathogenesis of neurodegenerative disorder such as Alzheimer's Disease (AD). Microglia, the main immune effector of the brain, are able to migrate to sites of Amyloid-beta (Aβ) deposition to eliminate Aβ phagocytosis upon activation by multiple receptors: Toll like receptors and scavenger receptors. The issue of whether microglia are able to eliminate pathological lesions such as neurofibrillary tangles or senile plaques from AD brain still remains the matter of controversy. Recent data suggest that the Nod Like Receptor 3 (NLRP3), multiprotein inflammasome complexes, plays a role in AD, as its activation in the microglia by Aβ triggers. IL-1β is produced as a biologically inactive pro-form and requires caspase-1 for activation and secretion. Caspase-1 activity is controlled by inflammasomes. We investigate about the importance of inflammasomes complex in the Aβ phagocytosis and its degradation. The preliminary results of phagocytosis assay and immunofluorescent experiment on primary Microglia cells to lipopolysaccharide (LPS) an Aβ exposure show that a previous treatment with LPS reduce Aβ phagocytosis. Different results were obtained in Primary Microglia wild type, NLRP3 and ASC Knockout suggesting a real inflammasomes involvement in Alzheimer's pathology. Inflammasomes inactivation reduces the production of inflammatory cytokines prolonging the protective activity of microglia and Aβ clearance, featuring a typical microglia phenotype of the early stage of AD disease.

Keywords: Alzheimer disease, innate immunity, neuroinflammation, NLRP3

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2250 Microstructural Investigation and Fatigue Damage Quantification of Anisotropic Behavior in AA2017 Aluminum Alloy under Cyclic Loading

Authors: Abdelghani May

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This paper reports on experimental investigations concerning the underlying reasons for the anisotropic behavior observed during the cyclic loading of AA2017 aluminum alloy. Initially, we quantified the evolution of fatigue damage resulting from controlled proportional cyclic loadings along the axial and shear directions. Our primary objective at this stage was to verify the anisotropic mechanical behavior recently observed. To accomplish this, we utilized various models of fatigue damage quantification and conducted a comparative study of the obtained results. Our analysis confirmed the anisotropic nature of the material under investigation. In the subsequent step, we performed microstructural investigations aimed at understanding the origins of the anisotropic mechanical behavior. To this end, we utilized scanning electron microscopy to examine the phases and precipitates in both the transversal and longitudinal sections. Our findings indicate that the structure and morphology of these entities are responsible for the anisotropic behavior observed in the aluminum alloy. Furthermore, results obtained from Kikuchi diagrams, pole figures, and inverse pole figures have corroborated these conclusions. These findings demonstrate significant differences in the crystallographic texture of the material.

Keywords: microstructural investigation, fatigue damage quantification, anisotropic behavior, AA2017 aluminum alloy, cyclic loading, crystallographic texture, scanning electron microscopy

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2249 Physicochemical and Thermal Characterization of Starch from Three Different Plantain Cultivars in Puerto Rico

Authors: Carmen E. Pérez-Donado, Fernando Pérez-Muñoz, Rosa N. Chávez-Jáuregui

Abstract:

Plantain contains starch as the majority component and represents a relevant source of this carbohydrate. Starches from different cultivars of plantain and bananas have been studied for industrialization purposes due to their morphological and thermal characteristics and their influence on food products. This study aimed to characterize the physical, chemical, and thermal properties of starch from three different plantains cultivated in Puerto Rico: Maricongo, Maiden, and FHIA 20. Amylose and amylopectin content, color, granular size, morphology, and thermal properties were determined. According to the content of amylose in starches, FHIA 20 starch presented minor content of the three cultivars studied. In terms of color, Maiden and FHIA 20 starch exhibited a significantly higher whiteness index comparing their values with Maricongo starch. The starches of the three cultivars had an elongated-ovoid morphology, with a smooth surface and a non-porous appearance. Regardless of similarities in their morphology, FHIA 20 showed a lower aspect ratio, which meant that their granules tended to be more elongated granules. Comparing the thermal properties of starches, it was found that the initial gelatinization temperature of the starch of the cultivars was similar. However, the final gelatinization temperatures of the starches belonging to the cultivars Maricongo (79.69°C) and Maiden (77.40°C) were similar, whereas FHIA 20 starch presented a noticeably higher final gelatinization temperature (87.95°C) and transition enthalpy. Despite source similarities, starches from plantain cultivars showed differences in their composition and thermal behavior. Therefore, this represents an opportunity to diversify their use in food-related applications.

Keywords: aspect ratio, morphology, Musa spp., starch, thermal properties

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2248 Economic Growth: The Nexus of Oil Price Volatility and Renewable Energy Resources among Selected Developed and Developing Economies

Authors: Muhammad Siddique, Volodymyr Lugovskyy

Abstract:

This paper explores how nations might mitigate the unfavorable impacts of oil price volatility on economic growth by switching to renewable energy sources. The impacts of uncertain factor prices on economic activity are examined by looking at the Realized Volatility (RV) of oil prices rather than the more traditional method of looking at oil price shocks. The United States of America (USA), China (C), India (I), United Kingdom (UK), Germany (G), Malaysia (M), and Pakistan (P) are all included to round out the traditional literature's examination of selected nations, which focuses on oil-importing and exporting economies. Granger Causality Tests (GCT), Impulse Response Functions (IRF), and Variance Decompositions (VD) demonstrate that in a Vector Auto-Regressive (VAR) scenario, the negative impacts of oil price volatility extend beyond what can be explained by oil price shocks alone for all of the nations in the sample. Different nations have different levels of vulnerability to changes in oil prices and other factors that may play a role in a sectoral composition and the energy mix. The conventional method, which only takes into account whether a country is a net oil importer or exporter, is inadequate. The potential economic advantages of initiatives to decouple the macroeconomy from volatile commodities markets are shown through simulations of volatility shocks in alternative energy mixes (with greater proportions of renewables). It is determined that in developing countries like Pakistan, increasing the use of renewable energy sources might lessen an economy's sensitivity to changes in oil prices; nonetheless, a country-specific study is required to identify particular policy actions. In sum, the research provides an innovative justification for mitigating economic growth's dependence on stable oil prices in our sample countries.

Keywords: oil price volatility, renewable energy, economic growth, developed and developing economies

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2247 Intelligent Recognition of Diabetes Disease via FCM Based Attribute Weighting

Authors: Kemal Polat

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In this paper, an attribute weighting method called fuzzy C-means clustering based attribute weighting (FCMAW) for classification of Diabetes disease dataset has been used. The aims of this study are to reduce the variance within attributes of diabetes dataset and to improve the classification accuracy of classifier algorithm transforming from non-linear separable datasets to linearly separable datasets. Pima Indians Diabetes dataset has two classes including normal subjects (500 instances) and diabetes subjects (268 instances). Fuzzy C-means clustering is an improved version of K-means clustering method and is one of most used clustering methods in data mining and machine learning applications. In this study, as the first stage, fuzzy C-means clustering process has been used for finding the centers of attributes in Pima Indians diabetes dataset and then weighted the dataset according to the ratios of the means of attributes to centers of theirs. Secondly, after weighting process, the classifier algorithms including support vector machine (SVM) and k-NN (k- nearest neighbor) classifiers have been used for classifying weighted Pima Indians diabetes dataset. Experimental results show that the proposed attribute weighting method (FCMAW) has obtained very promising results in the classification of Pima Indians diabetes dataset.

Keywords: fuzzy C-means clustering, fuzzy C-means clustering based attribute weighting, Pima Indians diabetes, SVM

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2246 Eco-Innovation: Perspectives from a Theoretical Approach and Policy Analysis

Authors: Natasha Hazarika, Xiaoling Zhang

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Eco- innovations, unlike regular innovations, are not self-enforcing and are associated with the double externality problem. Therefore, it is emphasized that eco-innovations need government. intervention in the form of supportive policies on priority. Off late, factors like consumer demand, technological advancement as well as the competitiveness of the firms have been considered as equally important. However, the interaction among these driving forces has not been fully traced out. Also, the theory on eco-innovation is found to be at a nascent stage which does not resonate with its dynamics as it is traditionally studied under the neo- classical economics theory. Therefore, to begin with, insights for this research have been derived from the merits of ‘neo- classical economics’, ‘evolutionary approach’, and the ‘resource based view’ which revealed the issues pertaining to technological system lock- ins and firm- based capacities which usually remained undefined by the neo classical approach; it would be followed by determining how the policies (in the national level) and their instruments are designed in order to motivate firms to eco-innovate, by analyzing the innovation ‘friendliness’ of the policy style and the policy instruments as per the indicators provided in innovation literature by means of document review (content analysis) of the relevant policies introduced by the Chinese government. The significance of theoretical analysis lies in its ability to show why certain practices become dominant irrespective of gains or losses, and that of the policy analysis lies in its ability to demonstrate the credibility of govt.’s sticks, carrots and sermons for eco-innovation.

Keywords: firm competency, eco-innovation, policy, theory

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2245 Determining Sources of Sediments at Nkula Dam in the Middle Shire River, Malawi, Using Mineral Magnetic Approach

Authors: M. K. Mzuza, W. Zhang, L. S. Chapola, M. Tembo

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Shire River is the largest and longest river in Malawi emptying its water into the Zambezi River in Mozambique. Siltation is now a major problem in the Shire River due to catchment degradation. This study analysed soil samples from tributaries of the Shire River to determine sources of sediments that cause siltation using the mineral magnetic approach. Bulk sediments and separated particle size fractions of representative samples were collected from tributaries on the western and eastern sides of the Shire River, and Nkula Dam. Eastern tributaries showed relatively higher ferrimagnetic mineral contents and ferrimagnetic to anti ferromagnetic ratios than western tributaries. Sediments from both sides of the Shire River were distinguished by χARM, SIRM versus χlf and S-100 versus SIRM. Findings in this study showed that most of the sediments originated from the western part of the Shire River. Tributaries on the eastern side of the Shire River had higher values for concentration related parameters (χlf, χfd, χARM, SIRM, HIRM, S-100, and χARM/SIRM) than tributaries on the western side. Bulky and detailed magnetic measurements carried out on particle size fractions provided additional confirmation of magnetic contrasts between the two sides of the river suggesting differences in lithology, topography, climate and weather regimes in the catchments. This study demonstrated that the magnetic approach can provide a reliable means of understanding major sediment sources of Nkula Dam and similar situations. It can also help to assess future variations in sediment composition resulting from catchment changes

Keywords: ferrimagnetic minerals, Shire River, tributaries rivers, particle size , topography

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2244 Advanced Phosphorus-Containing Polymer Materials towards Eco-Friendly Flame Retardant Epoxy Thermosets

Authors: Ionela-Daniela Carja, Diana Serbezeanu, Tachita Vlad-Bubulac, Corneliu Hamciuc

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Nowadays, epoxy materials are extensively used in ever more areas and under ever more demanding environmental conditions due to their remarkable combination of properties, light weight and ease of processing. However, these materials greatly increase the fire risk due to their flammability and possible release of toxic by-products as a result of their chemical composition which consists mainly from carbon and hydrogen atoms. Therefore, improving the fire retardant behaviour to prevent the loss of life and property is of particular concern among government regulatory bodies, consumers and manufacturers alike. Modification of epoxy resins with organophosphorus compounds, as reactive flame retardants or additives, is the key to achieving non-flammable advanced epoxy materials. Herein, a detailed characterization of fire behaviour for a series of phosphorus-containing epoxy thermosets is reported. A carefully designed phosphorus flame retardant additive was simply blended with a bifunctional bisphenol-A based epoxy resin. Further thermal cross-linking in the presence of various aminic hardeners led to eco-friendly flame retardant epoxy resins. The type of hardener, concentration of flame retardant additive, compatibility between the components of the mixture, char formation and morphology, thermal stability, flame retardant mechanisms were investigated. It was found that even a very low content of phosphorus introduced into the epoxy matrix increased the limiting oxygen index value to about 30%. In addition, the peak of the heat release rate value decreased up to 45% as compared to the one of the neat epoxy system. The main flame retardant mechanism was the condensed-phase one as revealed by SEM and XPS measurements.

Keywords: condensed-phase mechanism, eco-friendly phosphorus flame retardant, epoxy resin, thermal stability

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2243 High Precision 65nm CMOS Rectifier for Energy Harvesting using Threshold Voltage Minimization in Telemedicine Embedded System

Authors: Hafez Fouad

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Telemedicine applications have very low voltage which required High Precision Rectifier Design with high Sensitivity to operate at minimum input Voltage. In this work, we targeted 0.2V input voltage using 65 nm CMOS rectifier for Energy Harvesting Telemedicine application. The proposed rectifier which designed at 2.4GHz using two-stage structure found to perform in a better case where minimum operation voltage is lower than previous published paper and the rectifier can work at a wide range of low input voltage amplitude. The Performance Summary of Full-wave fully gate cross-coupled rectifiers (FWFR) CMOS Rectifier at F = 2.4 GHz: The minimum and maximum output voltages generated using an input voltage amplitude of 2 V are 490.9 mV and 1.997 V, maximum VCE = 99.85 % and maximum PCE = 46.86 %. The Performance Summary of Differential drive CMOS rectifier with external bootstrapping circuit rectifier at F = 2.4 GHz: The minimum and maximum output voltages generated using an input voltage amplitude of 2V are 265.5 mV (0.265V) and 1.467 V respectively, maximum VCE = 93.9 % and maximum PCE= 15.8 %.

Keywords: energy harvesting, embedded system, IoT telemedicine system, threshold voltage minimization, differential drive cmos rectifier, full-wave fully gate cross-coupled rectifiers CMOS rectifier

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2242 Field Studies of 2017 in the Water Catch Basin in the River Vere to Safeguard the Population of Tbilisi against the Erosive-Mudflow Processes and Its Evaluation

Authors: Natia Gavardashvili

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From April through June of 2017, the field-scientific studies to ensure the safety of the population of Tbilisi were accomplished in the water catch basin of the river Vere, in the water catch basin of the river Jakhana dry gully. 5 sensitive sites were identified, and areas, 20x20 m each, were marked around them, with their locations fixed with GPS coordinates. The gained areas were plotted on a digital map, and the state of the surface was explored by considering the evaluation of erosive processes. Aiming at evaluating the soils and grounds of the sensitive areas, the ground samples were taken, and average diameter was identified, with its value changing to D0 = 4,67-15,48 mm, and integral curves of the grain size were drafted. By using the obtained data, the transporting capability of mudflow can be identified at the next stage to use to calculate mudflow peak discharges of different provisions in developing the new designs of mudflow-protection structures with the goal of ensuring the safety of Tbilisi population. The studies were accomplished under the financing of Young Scientists’ Grant of Shota Rustaveli National Science Foundation 'The study of erosive-mudflow processes in the water catch basin in the river Vere to ensure the safety of the population of Tbilisi and their consideration in developing new environmental protection plans' (YS15_2.1.5_8)

Keywords: water catch basin, mudflow-protection structures, erosive-mudflow processes, safety

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2241 High-Pressure CO₂ Adsorption Capacity of Selected Unusual Porous Materials and Rocks

Authors: Daniela Rimnacova, Maryna Vorokhta, Martina Svabova

Abstract:

CO₂ adsorption capacity of several materials - waste (power fly ash, slag, carbonized sewage sludge), rocks (Czech Silurian shale, black coal), and carbon (synthesized carbon, activated carbon as a reference material) - were measured on dry samples using a unique hand-made manometric sorption apparatus at a temperature of 45 °C and pressures of up to 7 MPa. The main aim was finding utilization of the waste materials and rocks for removal of the air or water pollutants caused by anthropogenic activities, as well as for the carbon dioxide storage. The equilibrium amount of the adsorbate depends on temperature, gas saturation pressure, porosity, surface area and volume of pores, and last but not least, on the composition of the adsorbents. Given experimental conditions can simulate in-situ situations in the rock bed and can be achieved just by a high-pressure apparatus. The CO₂ excess adsorption capacities ranged from 0.018 mmol/g (ash) to 13.55 mmol/g (synthesized carbon). The synthetized carbon had the highest adsorption capacity among all studied materials as well as the highest price. This material is usually used for the adsorption of specific pollutants. The excess adsorption capacity of activated carbon was 9.19 mmol/g. It is used for water and air cleaning. Ash can be used for chemisorption onto ash particle surfaces or capture of special pollutants. Shale is a potential material for enhanced gas recovery or CO₂ sequestration in-situ. Slag is a potential material for capture of gases with a possibility of the underground gas storage after the adsorption process. The carbonized sewage sludge is quite a good adsorbent for the removal and capture of pollutants, as well as shales or black coal which show an interesting relationship between the price and adsorption capacity.

Keywords: adsorption, CO₂, high pressure, porous materials

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2240 Research on the Aesthetic Characteristics of Calligraphy Art Under The Cross-Cultural Background Based on Eye Tracking

Authors: Liu Yang

Abstract:

Calligraphy has a unique aesthetic value in Chinese traditional culture. Calligraphy reflects the physical beauty and the dynamic beauty of things through the structure of writing and the order of strokes to standardize the style of writing. In recent years, Chinese researchers have carried out research on the appreciation of calligraphy works from the perspective of psychology, such as how Chinese people appreciate the beauty of stippled lines, the beauty of virtual and real, and the beauty of the composition. However, there is currently no domestic research on how foreigners appreciate Chinese calligraphy. People's appreciation of calligraphy is mainly in the form of visual perception, and psychologists have been working on the use of eye trackers to record eye tracking data to explore the relationship between eye tracking and psychological activities. The purpose of this experimental study is to use eye tracking recorders to analyze the eye gaze trajectories of college students with different cultural backgrounds when they appreciate the same calligraphy work to reveal the differences in cognitive processing with different cultural backgrounds. It was found that Chinese students perceived calligraphy as words when viewing calligraphy works, so they first noticed fonts with easily recognizable glyphs, and the overall viewed time was short. Foreign students perceived calligraphy works as graphics, and they first noticed novel and abstract fonts, and the overall viewing time is longer. The understanding of calligraphy content has a certain influence on the appreciation of calligraphy works by foreign students. It is shown that when foreign students who understand the content of calligraphy works. The eye tracking path is more consistent with the calligraphy writing path, and it helps to develop associations with calligraphy works to better understand the connotation of calligraphy works. This result helps us understand the impact of cultural background differences on calligraphy appreciation and helps us to take more effective strategies to help foreign audiences understand Chinese calligraphy art.

Keywords: Chinese calligraphy, eye-tracking, cross-cultural, cultural communication

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2239 Efficiency of Membrane Distillation to Produce Fresh Water

Authors: Sabri Mrayed, David Maccioni, Greg Leslie

Abstract:

Seawater desalination has been accepted as one of the most effective solutions to the growing problem of a diminishing clean drinking water supply. Currently, two desalination technologies dominate the market – the thermally driven multi-stage flash distillation (MSF) and the membrane based reverse osmosis (RO). However, in recent years membrane distillation (MD) has emerged as a potential alternative to the established means of desalination. This research project intended to determine the viability of MD as an alternative process to MSF and RO for seawater desalination. Specifically the project involves conducting a thermodynamic analysis of the process based on the second law of thermodynamics to determine the efficiency of the MD. Data was obtained from experiments carried out on a laboratory rig. In order to determine exergy values required for the exergy analysis, two separate models were built in Engineering Equation Solver – the ’Minimum Separation Work Model’ and the ‘Stream Exergy Model’. The efficiency of MD process was found to be 17.3 %, and the energy consumption was determined to be 4.5 kWh to produce one cubic meter of fresh water. The results indicate MD has potential as a technique for seawater desalination compared to RO and MSF. However, it was shown that this was only the case if an alternate energy source such as green or waste energy was available to provide the thermal energy input to the process. If the process was required to power itself, it was shown to be highly inefficient and in no way thermodynamically viable as a commercial desalination process.

Keywords: desalination, exergy, membrane distillation, second law efficiency

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2238 Prevalence and Associated Factors with Burnout Among Secondary School Teachers in the City of Cotonou in Benin in 2022

Authors: Antoine Vikkey Hinson, Ranty Jolianelle Dassi, Menonli Adjobimey, Rose Mikponhoue, Paul Ayelo

Abstract:

Introduction: The psychological hardship of the teaching profession maintains a chronic stress that inevitably evolves into burnout (BO) in the absence of adequate preventive measures. The objective of this study is to study the prevalence and factors associated with burnout among secondary school teachers in the city of Cotonou in 2022. Methods: This was a descriptive cross-sectional study with an analytical aim and prospective data collection that took place over a period of 2 months, from July 19 to August 19 and from October 1 to October 31, 2022. Sampling was done using a three-stage probability sampling technique. Data analysis was performed using R 4.1.1 software. Bivariate logistic regression was used to identify associated factors. The significance level chosen was 5% (p < 0.05). Results: A total of 270 teachers were included in the study, of whom 208 (77.00%) were men. The mean age of the workers was 38.03 ± 8.30 years. According to the Maslach Burnout Inventory, 58.51% of the teachers had burnout, with 41.10% of teachers in emotional exhaustion, 27.40% in depersonalization and 21.90% in loss of personal accomplishment. The severity of the syndrome was low to moderate in almost all teachers. The occurrence of BO was associated with), not practicing sports (ORa= 2,38 [1,32; 4,28]), jobs training (ORa= 1,86 [1,04; 3,34]) and an imbalance of effort/reward (ORa= 5,98 [2,24;15,98]). Conclusion: The prevalence of BO is high among secondary school teachers in the city of Cotonou. A larger scale study, including research on its consequences on the teacher and the learner, is necessary in order to act quickly to implement a prevention program.

Keywords: burnout, teachers, Maslach burnout inventory, associated factors, Benin

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2237 Inoculation of Cyanobacteria Improves the Lignin Content of Thymus vulgaris L.

Authors: Nasim Rasuli, Akram Ahmadi, Hossein Riahi, Zeinab Shariatmadari, Majid Ghorbani Nohooji, Pooyan Mehraban Joubani

Abstract:

Cyanobacteria are one of the most promising sources of new biostimulants and have received much attention due to their diverse applications in biotechnology. These microorganisms enhance the growth and productivity of plants by producing plant growth stimulants and fixing atmospheric nitrogen. Thymus vulgaris L., a valuable medicinal plant from the Lamiaceae family, is widely distributed across the globe. essential oil of T. vulgaris is best characterized by the prominence of phenols, making them the key compounds in its composition. Lignin biosynthesis as a natural plant polyphenol plays a crucial role in promoting plant growth, strengthening cell walls, and increasing resistance to pathogens. In this study, the bioelicitor activity of five cyanobacterial suspensions including Anabaena torulosa ISB213, Nostoc calcicola ISB215, Nostoc ellipsosporum ISB217, Trichormus doliolum ISB214, and Oscillatoria sp. ISB2116 on the lignin content of the T. vulgaris L. was investigated. Pot experiments were performed by inoculation of a %2 algal extract to the soil of treated plants one week before planting and then every 20 days. After four months, the lignin content in the leaves of both treated and control plants was evaluated. The results demonstrated that the application of cyanobacteria significantly increased the lignin content in the leaves of treated plants compared to the control. The treatment with Oscillatoria sp. ISB216 and N. ellipsosporum ISB217 resulted in the highest lignin content, with an increase of 93.33% and 86.67%, respectively. These findings highlight the potential of cyanobacteria as bioelicitors, offering a viable alternative for enhancing the production of secondary metabolites in T. vulgaris. Consequently, this could contribute to the economic value of this medicinal plant.

Keywords: cyanobacteria, bioelicitor, thymus vulgaris, lignin

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2236 High Resolution Solid State NMR Structural Study of a Ternary Hydraulic Mixture

Authors: Rym Sassi, Franck Fayon, Mohend Chaouche, Emmanuel Veron, Valerie Montouillout

Abstract:

The chemical phenomena occurring during cement hydration are complex and interdependent, and even after almost two centuries of studies, they are still difficult to solve for complex mixtures combining different hydraulic binders. Powder-XRD has been widely used for characterizing the crystalline phases in both anhydrous and hydrated cement, but only limited information is obtained in the case of strongly disordered and amorphous phases. In contrast, local spectroscopies like solid-state NMR can provide a quantitative description of noncrystalline phases. In this work, the structural modifications occurring during hydration of a fast-setting ternary binder based on white Portland cement, white calcium aluminate cement, and calcium sulfate were investigated using advanced solid-state NMR methods. We particularly focused on the early stage of the hydration up to 28 days, working with samples whose hydration was controlled and stopped. ²⁷Al MQ-MAS as well as {¹H}-²⁷Al and {¹H}-²⁹Si Cross- Polarization MAS NMR techniques were combined to distinguish all of the aluminum and silicon species formed during the hydration. The NMR quantification of the different phases was conducted in parallel with the XRD analyses. The consumption of initial products, as well as the precipitation of hydraulic phases (ettringite, monosulfate, strätlingite, CSH, and CASH), were unambiguously quantified. Finally, the drawing of the consumption and formation of phases was correlated with mechanical strength measurements.

Keywords: cement, hydration, hydrates structure, mechanical strength, NMR

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2235 One Building at a Time for Tambak Lorok

Authors: Etika Sukma Adiyanti, H. N. Nurul Huda Putu Ekapraja, Gugun Gunawan

Abstract:

Global warming causes climate change and sea level rise. This is a threat for coastal regions, especially for coastal settlements with activities that are influenced by this natural phenomenon. Consequences are damage of houses, humid house environment, sustainability of the houses, obstructed economic activities and domestic works, disruption of sanitation facilities, lack of electricity, failure of transport system, psychological issues and other. Icons Tambak Lorok as 'Fisherman Village' is not something familiar to residents of the city of Semarang. Especially for the housewife who every day have to buy the ingredients high in protein and omega fish auction which is adjacent to the main street market in the village of Tambak Lorok. However, there are major problems that are being experienced by this small neighborhood. In fact, this issue includes seven infrastructure that should spoil the fishermen in activity with marine life. With this research, we will investigate water urbanism and climate change resiliency in Semarang, specifically the traditional fisher community of Tambak Lorok. We intend to find out how the local people in the fisher settlement Tambak Lorok deal with water urbanism, proverty and living with floods. So, we have a good solution for this problem, Floating Stage. We think that Tambak Lorok needs a new design for the common future. With this, One Building at A Time for Tambak Lorok, will be a good solution.

Keywords: fisher community, environment, climate change, settlement

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2234 National Identity in Connecting the Community through Mural Art for Petronas Dagangan Berhad

Authors: Nadiah Mohamad, Wan Samiati Andriana Wan Mohd Daud, M. Suhaimi Tohid, Mohd Fazli Othman, Mohamad Rizal Salleh

Abstract:

This is a collaborative project of the mural art between The Department of Fine Art from Universiti Teknologi MARA (UiTM) and Petronas Dagangan Berhad (PDB), the most leading retailer and marketer of downstream oil and gas products in Malaysia. Five different states in the Peninsular of Malaysia that has been identified in showcasing the National Identity of Malaysia at each Petronas gas station, this also includes the Air Keroh in Melaka, Pasir Pekan in Kelantan, Pontian in Johor, Simpang Pulai in Perak, and also Wakaf Bharu in Terengganu. This project is to analyze the element of national identity that has been demonstrated at the Petronas's Mural. The ultimate aim of the mural is to let the community and local people to be aware about what Malaysians are consists and proud of and how everyone is able to connect with the idea through visual art. The method that is being explained in this research is by using visual data through research and also self-experience in collecting the visual data in identifying what images is considered as the national identity and idea development and visual analysis is being transferred based upon the visual data collection. In this stage, elements and principles of design will be the key in highlighting what is necessary for a work of art. In conclusion, visual image of the National Identity of Malaysia is able to connect to the audience from local and also to the people from outside the country to learn and understand the beauty and diversity of Malaysia as a unique country with art through the wall of five Petronas gas station.

Keywords: community, fine art, mural art, national identity

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2233 Phase Behavior Modelling of Libyan Near-Critical Gas-Condensate Field

Authors: M. Khazam, M. Altawil, A. Eljabri

Abstract:

Fluid properties in states near a vapor-liquid critical region are the most difficult to measure and to predict with EoS models. The principal model difficulty is that near-critical property variations do not follow the same mathematics as at conditions far away from the critical region. Libyan NC98 field in Sirte basin is a typical example of near critical fluid characterized by high initial condensate gas ratio (CGR) greater than 160 bbl/MMscf and maximum liquid drop-out of 25%. The objective of this paper is to model NC98 phase behavior with the proper selection of EoS parameters and also to model reservoir depletion versus gas cycling option using measured PVT data and EoS Models. The outcomes of our study revealed that, for accurate gas and condensate recovery forecast during depletion, the most important PVT data to match are the gas phase Z-factor and C7+ fraction as functions of pressure. Reasonable match, within -3% error, was achieved for ultimate condensate recovery at abandonment pressure of 1500 psia. The smooth transition from gas-condensate to volatile oil was fairly simulated by the tuned PR-EoS. The predicted GOC was approximately at 14,380 ftss. The optimum gas cycling scheme, in order to maximize condensate recovery, should not be performed at pressures less than 5700 psia. The contribution of condensate vaporization for such field is marginal, within 8% to 14%, compared to gas-gas miscible displacement. Therefore, it is always recommended, if gas recycle scheme to be considered for this field, to start it at the early stage of field development.

Keywords: EoS models, gas-condensate, gas cycling, near critical fluid

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2232 Development of Materials Based on Phosphates of NaZr2(PO4)3 with Low Thermal Expansion

Authors: V. Yu. Volgutov, A. I. Orlova, S. A. Khainakov

Abstract:

NaZr2(PO4)3 (NZP) and their structural analogues are characterized by a peculiar behaviors on heating – they have different expansion and contraction along different crystallographic directions due to specific arrangements of crystal structure in these compounds. An important feature of such structures is the ability to incorporate into their structural analogues wide variety of metal cations having different size and oxidation states, with different combinations and concentrations. These cations are located in different crystallographic non-equivalent positions of octahedral tetrahedral crystal framework as well as in inter-framework cavities. Through, due to iso- and hetero-valent isomorphism of the cations (and the anions) in NZP, it becomes possible to tuning the compositions and to obtain the compounds with ‘on a plan’ properties. For the design of compounds with low and ultra-low thermal expansion including those with tailored thermal expansion properties, the following crystallochemical principles it seems are promising: 1) Insertion into crystal M1 position the cations having different sizes and, 2) the variation in the composition of compounds, providing different occupation of crystal M1 position. Following these principles we have designed and synthesized the next NZP-type phosphates series: a) where radii of the cations in the M1 crystal position was varied: Zr1/4Zr2(PO4)3 - Th1/4Zr2(PO4)3 (series I); R1/3Zr2(PO4)3 where R= Nd, Eu, Er (series II), b) where the occupation of M1 crystal position was varied: Zr1/4Zr2(PO4)3-Er1/3Zr2(PO4)3 (series III) and Zr1/4Zr2(PO4)3-Sr1/2Zr2(PO4)3 (series IV). The thermal expansion parameters were determined over the range of 25-800ºC. For each series the minimum axial coefficient of thermal expansion αa = αb, αc and their anisotropy Δα = Iαa - αcI, 10-6 K-1 was found as next: -1.51, 1.07, 2.58 for Th1/4Zr2(PO4)3 (series I); -0.72, 0.10, 0.81 for Nd1/3Zr2(PO4)3 (series II); -2.78, 1.35, 4.12 for Er1/6Zr1/8Zr2(PO4)3 (series III); 2.23, 1.32, 0.91 for Sr1/2Zr2(PO4)3 (series IV). The measured tendencies of the thermal expansion of crystals were in good agreement with predicted ones. For one of the members from the studied phosphates namely Th1/16Zr3/16Zr2(PO4)3 structural refinement have been carried out at 25, 200, 600, and 800°C. The dependencies of the structural parameters with the temperature have been determined.

Keywords: high-temperature crystallography, NaZr2(PO4)3, (NZP) analogs, structural-chemical principles, tuning thermal expansion

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