检索结果-南通市图书馆

Phosphoric Acid Pretreatment and Saccharification of Paper Sludge as a Renewable Material for Cellulosic Fibers

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Renewable Materials 2024年第9期12卷 1573-1591页

作者： Samar el-Mekkawi Wafaa Abou-elseoud Shaimaa Fadel Enas Hassan Mohammad Hassan Chemical Engineering and Pilot Plant Department National Research CentreDokkiGiza12622Egypt Cellulose and Paper Department National Research CentreDokkiGiza12622Egypt

Recycling of paper sludge waste is crucial for establishing a sustainable green *** waste contains valuable sugars that can be converted into important chemicals such as ethanol,poly hydroxybutyrate,and lactic ***,the main challenge in obtaining sugars in high yield from paper sludge is the high crystallinity of cellulose,which hinders *** address this,pretreatment using phosphoric acid was optimized using response surface methodology to facilitate cellulose hydrolysis with minimal energy and *** created prediction model using the response surface method considered factors such as acid concentration(ranging from 60%to 85%),consistency(ranging from 4%to 10%),temperature(ranging from 25℃to 80℃),and time(ranging from 0.5 to 4 h).The results revealed that the model’s significant factors affecting the yield were acid concentration,reaction time,temperature,and the product of acid concentration and temperature,while the model’s significant factors affecting the crystallinity were the consistency,the temperature,and their *** results showed that the optimum conditions for pretreatment were using an acid concentration of 64%,temperature of 25℃,consistency of 10%,and time of 30 *** hydrolysis of the conditionally pretreated paper sludge resulted in a weight loss of 42%,compared to only 18%weight loss in non-pretreated paper ***,the optimized conditions led to low levels of furfurals and acetic acid,which are undesirable by-products that can interfere with sugar *** total sugar obtained under the optimized conditions was 0.43 g glucose/g sample(10.46 g/L),while the contents of methyl furfural,furfural,and acetic acid were 21.65,235.7,and 4.57 mg/L,*** study demonstrates the potential of phosphoric acid for pretreatment and hydrolysis of paper sludge,enabling efficient saccharification and the production of sugars with minimal undesired by-products.

关键词： Waste valorization fermentable sugars response surface methodology acid hydrolysis cellulose crystallinity

Thermodynamic Performance Analysis of Geothermal Power Plant Based on Organic Rankine Cycle (ORC) Using Mixture of Pure Working Fluids

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Energy Engineering 2024年第8期121卷 2023-2038页

作者： Abdul Sattar Laghari Mohammad Waqas Chandio Laveet Kumar Mamdouh el Haj Assad Department of Mechanical Engineering Mehran University of Engineering and TechnologyJamshoro76062Pakistan Department of Mechanical and Industrial Engineering College of EngineeringQatar UniversityDoha00000Qatar Sustainable&Renewable Energy Engineering Department University of SharjahSharjah00000United Arab Emirates

The selection of working fluid significantly impacts the geothermal ORC’s *** a mixture as a working fluid is a strategy to improve the output of geothermal *** the current study,modelling and thermodynamic analysis of ORC,using geothermal as a heat source,is carried out at fixed operating *** model is simulated in the Engineering Equation Solver(EES).An environment-friendly mixture of fluids,i.e.,R245fa/R600a,with a suitable mole fraction,is used as the operating *** mixture provided the most convenient results compared to the pure working fluid under fixed operating *** impact of varying the evaporator pressure on the performance parameters,including energy efficiency,exergy efficiency and net power output is *** system provided the optimal performance once the evaporator pressure reached the maximum *** efficiencies:Energy and Exergy,and Net Power output of the system are 16.62%,64.08%and 2199 kW for the basic cycle and 20.72%,67.76%and 2326 kW respectively for the regenerative cycle.

关键词： Organic rankine cycle internal heat exchanger moderate-temperature geothermal source mixture of the fluid exergy

Modelling the monthly hydrological balance using Soil and Water Assessment Tool(SWAT)model:A case study of the Wadi Mina upstream watershed

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Groundwater Science and Engineering 2024年第2期12卷 161-177页

作者： Hanane Mebarki Noureddine Maref Mohammed el-Amine Dris Civil Engineering and Environmental Laboratory(LGCE) University of Djillali LiabèsFaculty of TechnologyHydraulics departmentBen M'Hidi districtP.O.Box 8922000Sidi Bel AbbèsAlgeria.

Modelling the hydrological balance in semi-arid zones is essential for effective water resource management,encompassing both surface water and *** study aims to model the monthly hydrological water cycle in the Wadi Mina upstream watershed(northwest Algeria)by applying the Soil and Water Assessment Tool(SWAT)hydrological *** modelling integrates spatial data such as the Digital elevation Model(DEM),land use,soil types and various meteorological parameters including precipitation,maximum and minimum temperatures,relative humidity,solar radiation and wind *** SWAT model was calibrated and validated using data from January 2012 to December 2014,with a calibra-tion period from January 2012 to August 2013 and a validation period from September 2013 to December *** and parameter calibration were conducted using the SWAT-SA program,and model performance evaluation relied on comparing the observed discharge at the outlet of the basin with model-simulated discharge,assessed through statistical coefficients including Nash-Sutcliffe Efficiency(NSE),coefficient of determination(R2)and Percent Bias(PBAIS).Calibration results indicated favourable objec-tive function values(NSE=0.79,R2=0.93,PBAIS=-8.53%),although a slight decrease was observed during validation(NSE=0.69,R2=0.86,and PBAIS=-11.41%).The application of the SWAT model to the Wadi Mina upstream watershed highlighted its utility in simulating the spatial distribution of different components of the hydrological balance in this *** SWAT model revealed that approximately 71%of the precipitation in the basin evaporates,while only 29%contributes to surface runoff or infiltration into the soil.

关键词： SWAT model Performance Parameters Runoff Groundwater Wadi

Gut microbiota predicts the diagnosis of ulcerative colitis in Saudi children

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Clinical Pediatrics 2024年第1期13卷 118-124页

作者： Mohammad el Mouzan Ahmed Al Sarkhy Asaad Assiri Department of Pediatrics Gastroenterology UnitKing Saud UniversityRiyadh 11461Saudi Arabia

BACKGROUND Ulcerative colitis(UC)is an immune-mediated chronic inflammatory condition with a worldwide *** the etiology of this disease is still unknown,the understanding of the role of the microbiota is becoming increasingly *** To investigate the predictive power of the gut microbiota for the diagnosis of UC in a cohort of newly diagnosed treatment-naïve Saudi children with *** The study population included 20 children with a confirmed diagnosis of UC and 20 healthy *** DNA was extracted and sequenced,and shotgun metagenomic analysis was performed for bacteria and *** and bioinformatics demonstrated significant dysbiosis in the form of reduced alpha diversity,beta diversity,and significant difference of abundance of taxa between children with UC and control *** receiver operating characteristic curve,a probability curve,was used to determine the difference between the UC and control *** area under the curve(AUC)represents the degree of separability between the UC group and the control *** AUC was calculated for all identified bacterial species and for bacterial species identified by the random forest classification algorithm as important potential biomarkers of UC.A similar method of AUC calculation for all bacteriophages and important species was *** The median age and range were 14(0.5-21)and 12.9(6.8-16.3)years for children with UC and controls,respectively,and 40%and 35%were male for children with UC and controls,*** AUC for all identified bacterial species was 89.5%.However,when using the bacterial species identified as important by random forest classification algorithm analysis, the accuracy increased to 97.6%. Similarly, the AUC for all theidentified bacteriophages was 87.4%, but this value increased to 94.5% when the important bacteriophagebiomarkers were *** very high to excellent AUCs of fecal bacterial and viral species sugge

关键词： Ulcerative colitis Microbiota Area under the curve Children Saudi Arabia

Modern Mobile Malware Detection Framework Using Machine Learning and Random Forest Algorithm

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computer Systems Science & Engineering 2024年第5期48卷 1171-1191页

作者： Mohammad Ababneh Ayat Al-Droos Ammar el-Hassan School of Computing Sciences Princess Sumaya University for TechnologyAmman11941Jordan

With the high level of proliferation of connected mobile devices,the risk of intrusion becomes *** Intelligence(AI)and Machine Learning(ML)algorithms started to feature in protection software and showed effective *** algorithms are nonetheless hindered by the lack of rich datasets and compounded by the appearance of new categories of malware such that the race between attackers’malware,especially with the assistance of Artificial Intelligence tools and protection solutions makes these systems and frameworks lose effectiveness *** this article,we present a framework for mobile malware detection based on a new dataset containing new categories of mobile *** focus on categories of malware that were not tested before by Machine Learning algorithms proven effective in malware *** carefully select an optimal number of features,do necessary preprocessing,and then apply Machine Learning algorithms to discover malicious code *** our experiments,we have found that the Random Forest algorithm is the best-performing algorithm with such mobile malware with detection rates of around 99%.We compared our results from this work and found that they are aligned well with our previous *** also compared our work with State-of-the-Art works of others and found that the results are very close and competitive.

关键词： Android malware detect prevent artificial intelligence machine learning mobile CICMalDroid2020 CCCSCIC-AndMal-2020

Multi-Objective Optimization Algorithm for Grouping Decision Variables Based on Extreme Point Pareto Frontier

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第4期79卷 1281-1299页

作者： JunWang Linxi Zhang Hao Zhang Funan Peng Mohammed A.el-Meligy Mohamed Sharaf Qiang Fu College of Computer Science and Technology Shenyang University of Chemical TechnologyShenyang110142China Key Laboratory of Intelligent Technology for Chemical Process Industry of Liaoning Province Shenyang University of Chemical TechnologyShenyang110142China Industrial Engineering Department College of EngineeringKing Saud UniversityP.O.Box 800Riyadh11421Saudi Arabia

The existing algorithms for solving multi-objective optimization problems fall into three main categories:Decomposition-based,dominance-based,and *** multi-objective optimization problemsmainly focus on objectives,treating decision variables as a total variable to solve the problem without consideringthe critical role of decision variables in objective *** seen,a variety of decision variable groupingalgorithms have been ***,these algorithms are relatively broad for the changes of most decisionvariables in the evolution process and are time-consuming in the process of finding the Pareto *** solvethese problems,a multi-objective optimization algorithm for grouping decision variables based on extreme pointPareto frontier(MOEA-DV/EPF)is *** algorithm adopts a preprocessing rule to solve the Paretooptimal solution set of extreme points generated by simultaneous evolution in various target directions,obtainsthe basic Pareto front surface to determine the convergence effect,and analyzes the convergence and distributioneffects of decision *** the later stages of algorithm optimization,different mutation strategies are adoptedaccording to the nature of the decision variables to speed up the rate of evolution to obtain excellent individuals,thusenhancing the performance of the *** validation of the test functions shows that this algorithmcan solve the multi-objective optimization problem more efficiently.

关键词： Multi-objective evolutionary optimization algorithm decision variables grouping extreme point pareto frontier

Saffron(Crocus sativus L.) stigmas as a potential natural additive to improve oxidative stability attributes of sunflower(Helianthus annuus L.) oil stored under different conditions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Grain & Oil Science and Technology 2024年第3期7卷 133-149页

作者： Moussa Nid Ahmed Karima Abourat Jamila Gagour el Hassan Sakar Khalid Majourhat Said Gharby Biotechnology Analytical Sciences and Quality Control TeamPolydisciplinary Faculty of TaroudantUniversity Ibnou ZohrMorocco Laboratory of Biology Ecologyand HealthFSAbdelmalek Essaadi UniversityTetouanMorocco Geo-Bio-Environmental Engineering and Innovation Laboratory Polydisciplinary Faculty of TaroudantUniversity Ibnou ZohrAgadirMorocco

The aim of our study was to explore the antioxidant potential of Moroccan saffron stigmas(SS) and examine their performance as a natural antioxidant in enhancing the stability and quality properties of edible sunflower oil(SO), with a focus on understanding the critical importance of edible oil stability for predicting quality deterioration during storage. Bearing this in mind, our research was designed to compare the efficacy of three concentrations of dried SS(at 0.2%, 0.3%, and 0.6%) against tocobiol(a synthetic antioxidant) as a positive control(at 0.3% concentration). This comparison was conducted under three distinct storage conditions namely accelerated ageing(60 ℃), exposure to light at ambient temperature, and darkness, to evaluate their impact on preventing severe oxidation and extending oil shelf-life. Oxidation state evolution was evaluated through peroxide value(PV), free fatty acid(FFA), anisidine value(p-AV), K_(270)value(conjugated trienes), total oxidation index(TOTOX), iodine value(IV), and fatty acid composition(FA). Our results revealed notable differences in stability tracking parameters. Specifically, these parameters were higher in samples stored under accelerated conditions, followed by the samples stored in ambient light, while those stored in darkness showed the highest stability among the three storage conditions. Supplementation of sunflower oil with SS and tocobiol significantly enhanced its oxidation stability. Notably, SS exhibited exceptional effectiveness in stabilizing sunflower oil regardless of SS dose, with the highest efficacy observed at 0.6%. This was evidenced by the slower rate of oxidation parameters under various storage conditions, highlighting a superior antioxidant activity compared to both the non-enriched oil and tocobiol-enriched oil. Furthermore, saffron stigmas, used as a natural supplement,contributed to the preservation of polyunsaturated fatty acids, indicating its potential as a robust source of natural antioxi

关键词： Crocus sativus L. Helianthus annuus L. Saffron stigmas Shelf-life Sunflower oil Tocobiol

Toward understanding the microstructure characteristics,phase selection and magnetic properties of laser additive manufactured Nd-Fe-B permanent magnets

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

International Journal of Extreme Manufacturing 2024年第1期6卷 277-294页

作者： Bo Yao Nan Kang Xiangyu Li Dou Li Mohamed el Mansori Jing Chen Haiou Yang Hua Tan Xin Lin State Key Laboratory of Solidiffcation Processing Northwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China Arts et Metiers Institute of Technology MSMPHESAM UniversitéF-51006 Chˆalons-en-ChampagneFrance Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design MIIT ChinaNorthwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China Texas A&M Engineering Experiment Station Institute for Manufacturing SystemsCollege StationTX 77843United States of America

Nd-Fe-B permanent magnets play a crucial role in energy conversion and electronic *** essential magnetic properties of Nd-Fe-B magnets,particularly coercivity and remanent magnetization,are significantly infuenced by the phase characteristics and *** this work,Nd-Fe-B magnets were manufactured using vacuum induction melting(VIM),laser directed energy deposition(LDED)and laser powder bed fusion(LPBF)*** evolution and phase selection of Nd-Fe-B magnets were then clarified in *** results indicated that the solidification velocity(V)and cooling rate(R)are key factors in the phase *** terms of the VIM-casting Nd-Fe-B magnet,a large volume fraction of theα-Fe soft magnetic phase(39.7 vol.%)and Nd2Fe17Bxmetastable phase(34.7 vol.%)areformed due to the low R(2.3×10-1?C s-1),whereas only a minor fraction of the Nd2Fe14B hard magnetic phase(5.15 vol.%)is *** the LDED-processed Nd-Fe-B deposit,although the Nd2Fe14B hard magnetic phase also had a low value(3.4 vol.%)as the values of V(10-2m s-1)and R(1.45×106?C s-1)in the LPBF process resulted in the substantial formation of the Nd2Fe14B hard magnetic phase(55.8 vol.%)directly from the liquid,while theα-Fe soft magnetic phase and Nd2Fe17Bxmetastable phase precipitation are suppressed in the LPBF-processed Nd-Fe-B ***,crystallographic texture analysis reveals that the LPBF-processedNd-Fe-B magnets exhibit isotropic magnetic ***,the LPBF-processed Nd-Fe-B deposit,exhibiting a coercivity of 656 k A m-1,remanence of 0.79 T and maximum energy product of 71.5 k J m-3,achieved an acceptable magnetic perfor

关键词： laser additive manufacturing(LAM) Nd-Fe-B permanent magnets numerical simulation microstructure magnetic properties

Assessment of plant diversity of endemic species of the Saharo-Arabian region in Egypt

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Journal of Arid Land 2024年第7期16卷 1000-1021,I0002-I0044页

作者： Asmaa S ABO HATAB Yassin M AL-SODANY Kamal H SHALTOUT Soliman A HAROUN Mohamed M el-KHALAFY Botany and Microbiology Department Faculty of ScienceKafrelsheikh UniversityKafrelsheikh 33511Egypt Botany Department Faculty of ScienceTanta UniversityTanta 31527Egypt

Savanna, semi-deserts, and hot deserts characterize the Saharo-Arabian region, which includes Morocco, Mauretania, Algeria, Tunisia, Libya, Egypt, Palestine, Kuwait, Saudi Arabia, Qatar, Bahrain, the United Arab Emirates, Oman, Yemen, southern Jordan, Syria, Iraq, Iran, Afghanistan, Pakistan, and northern India. Its neighboring regions, the Sudano-Zambezian region belonging to the Paleotropical Kingdom and the Mediterranean and Irano-Turanian regions included in the Holarctic Kingdom, share a large portion of their flora with the Saharo-Arabian region. Despite the widespread acknowledgment of the region's global importance for plant diversity, an up to date list of the Saharo-Arabian endemics is still unavailable. The available data are frequently insufficient or out of date at both the whole global and the national scales. Therefore, the present study aims at screening and verifying the Saharo-Arabian endemic plants and determining the phytogeographical distribution of these taxa in the Egyptian flora. Hence, a preliminary list of 429 Saharo-Arabian endemic plants in Egypt was compiled from the available literature. Indeed, by excluding the species that were recorded in any countries or regions outside the Saharo-Arabian region based on different literature, database reviews, and websites, the present study has reduced this number to 126 taxa belonging to 87 genera and 37 families. Regarding the national geographic distribution, South Sinai is the richest region with 83 endemic species compared with other eight phytogeographic regions in Egypt, followed by the Isthmic Desert(the middle of Sinai Peninsula, 53 taxa). Sahara regional subzone(SS1) distributes all the 126 endemic species, Arabian regional subzone(SS2) owns 79 taxa, and Nubo-Sindian subzone(SS3) distributes only 14 endemics. Seven groups were recognized at the fourth level of classification as a result of the application of the two-way indicator species analysis(TWINSPAN) to the Saharo-Arabian endemic sp

关键词： endemism phytogeographical regions Saharo-Arabian floristic region Egyptian flora plant diversity two-way indicator species analysis(TWINSPAN)