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Quantifying major sources of uncertainty in projecting the impact of climate change on wheat grain yield in dryland environments

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Journal of Arid Land 2023年第5期15卷 545-561页

作者： Reza DEIHIMFARD sajjad rahimi-moghaddam Farshid JAVANSHIR Alireza PAZOKI Department of Agroecology Environmental Sciences Research InstituteShahid Beheshti UniversityTehran 19839–69411Iran Department of Production Engineering and Plant Genetics Faculty of Agriculture and Natural ResourcesLorestan UniversityKhorramabad 68151–44316Iran Department of Agrotechnology Yadegar-e-Imam Khomeini(RAH)Shahre Rey BranchIslamic Azad UniversityTehran 18151–63111Iran

Modelling the impact of climate change on cropping systems is crucial to support policy-making for farmers and ***,there exists inherent uncertainty in such *** Circulation Models(GCMs)and future climate change scenarios(different Representative Concentration Pathways(RCPs)in different future time periods)are among the major sources of uncertainty in projecting the impact of climate change on crop grain *** study quantified the different sources of uncertainty associated with future climate change impact on wheat grain yield in dryland environments(Shiraz,Hamedan,Sanandaj,Kermanshah and Khorramabad)in eastern and southern *** five representative locations can be categorized into three climate classes:arid cold(Shiraz),semi-arid cold(Hamedan and Sanandaj)and semi-arid cool(Kermanshah and Khorramabad).Accordingly,the downscaled daily outputs of 29 GCMs under two RCPs(RCP4.5 and RCP8.5)in the near future(2030s),middle future(2050s)and far future(2080s)were used as inputs for the Agricultural Production Systems sIMulator(APSIM)-wheat *** of variance(ANOVA)was employed to quantify the sources of uncertainty in projecting the impact of climate change on wheat grain *** from 1980 to 2009 were regarded as the baseline *** projection results indicated that wheat grain yield was expected to increase by 12.30%,17.10%,and 17.70%in the near future(2030s),middle future(2050s)and far future(2080s),*** increases differed under different RCPs in different future time periods,ranging from 11.70%(under RCP4.5 in the 2030s)to 20.20%(under RCP8.5 in the 2080s)by averaging all GCMs and locations,implying that future wheat grain yield depended largely upon the rising CO2 *** results revealed that more than 97.22% of the variance in future wheat grain yield was explained by locations,followed by scenarios,GCMs,and their ***,at the semi-arid climate locations(Hamedan,S

关键词： wheat grain yield climate change Agricultural Production Systems sIMulator(APSIM)-wheat model General Circulation Models(GCMs) arid climate semi-arid climate Iran

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Spaceborne and ground-based sensor collaboration:Advancing resident space objects’orbit determination for space sustainability

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Astrodynamics 2024年第3期8卷 325-347页

作者： Niki sajjad Mehran Mirshams Andreas Makoto Hein Space Research Laboratory Department of Aerospace EngineeringK.N.Toosi University of TechnologyTehran16569-83911Iran Interdisciplinary Centre for Security Reliability and Trust(SnT)University of LuxembourgLuxembourg1855Luxembourg

The limited space around the Earth is getting cluttered with leftover fragments from old missions,creating a real *** more satellites are launched,even debris pieces as small as 5 mm must be tracked to avoid ***,it is an arduous and challenging task in *** paper presents a technical exploration of ground-based and in-orbit space debris tracking and orbit determination *** highlights the challenges faced during on-ground and in-orbit demonstrations,identifies current gaps,and proposes solutions following technological advancements,such as low-power pose estimation *** to the numerous atmospheric barriers to ground-based sensors,this study emphasizes the significance of spaceborne sensors for precise orbit determination,complemented by advanced data processing algorithms and collaborative *** ultimate goal is to create a comprehensive catalog of resident space objects(RSO)around the Earth and promote space environment *** exploring different methods and finding innovative solutions,this study contributes to the protection of space for future exploration and the creation of a more transparent and precise map of orbital objects.

关键词： resident space objects(RSO) space debris orbit determination tracking ground-based sensors spaceborne sensors

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PdCu alloy anchored defective titania for photocatalytic conversion of carbon dioxide into methane with 100% selectivity

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Journal of Energy Chemistry 2024年第4期91卷 254-265页

作者： Lina Zhang sajjad Hussain Qiuye Li Jianjun Yang National&Local Joint Engineering Research Center for Applied Technology of Hybrid Nanomaterials Henan UniversityKaifeng 475004HenanChina

The photoreduction of CO_(2)into CH_(4)with simultaneous high activity and selectivity is a promising strategy to increase energy supply and alleviate global ***,the absence of the active sites that is responsible for the adsorption and activation of CO_(2)and the generation of CO and H2via side reactions often lead to poor efficiency and low selectivity of the ***,Cu,Pd,and PdCu metal clusters cocatalyst-anchored defective TiO_(2)nanotubes(Cu/TiO_(2)-SBO,Pd/TiO_(2)-SBO,and Pd1Cu1/TiO_(2)-SBO)were designed via a simple solution impregnation reduction and applied for photocatalytic conversion of CO_(2)to CH_(4).The Pd1Cu1/TiO_(2)-SBO photocatalyst exhibits excellent catalytic performance among the other catalysts for photoreduction of CO_(2)into CH_(4).More interestingly,the product selectivity of CH_(4)reaches up to 100%with a rate of 25μmol g^(-1)h^(-1).In-situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTS)and density functional theory(DFT)simulations indicate that the main reasons for the high selectivity of CH_(4)are attributed to the PdCu alloy and oxygen vacancies,which jointly enhance the photoinduced carrier separation and lower energy barriers of key ***,due to the tunable d-band center of the Cu site in the PdCu alloy,the generated intermediates can be well prevented from poisoning and promoted to participate in further ***,the current study will provide insight into the development of new,highly selective photocatalysts for the visible light-catalytic reduction of CO_(2)into CH_(4).

关键词： PdCu alloy Defective TiO_(2) Photoreduction of CO_(2) Photocatalytic mechanism

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Fabrication and application prospects of Pr-Fe-B/Alnico nanocomposite alloys

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Journal of Rare Earths 2024年第9期42卷 1717-1723,I0003页

作者： Hui Liang sajjad Ur Rehman Ruibiao Zhang Yongqiang Deng Haihua Liu Munan Yang National Rare Earth Functional Materials Innovation Center College of Rare EarthsJiangxi University of Science and TechnologyGanzhou341000China Zhejiang Tiantong Electronic Information Materials Research Institute Co. Ltd.Haining314400China

The potentials of rare earth-based nanocomposite alloys have never been realized due to strict microstructural *** to the easy demagnetization it is challenging to increase the soft magnetic phase *** avoid the easy demagnetization,Pr-Fe-B/Alnico magnets were fabricated and reported in this *** content of the Alnico phase is increased from 0 to 25 wt%,while the content of Pr element is reduced to below the sub-stoichiometry of the 2:14:1 main *** maximum magnetic energy product,which is the figure-of-merit for permanent magnets,is increased from 122 kJ/m^(3) for the standard alloy to 146 kJ/m^(3) for the alloy with 15 wt% Alnico which shows a significant improvement considering the fact that the Curie point of the magnet is also increased by~66 *** special microstructure contains distinctly and heterogeneously distributed 2:14:1 and Alnico *** dimensions of neither the 2:14:1 nor the Alnico phases meet the dimensional requirements of the nanocomposite magnets,but still the smooth demagnetization curves are noted for the *** behavior of effective anisotropy,the performance of the magnets in applied magnetic field and the magnetic interactions among the various constituent grains were quantitatively studied by reversible susceptibility,irreversible susceptibility and re coil loop *** study may provide some guiding principles for the development of nanocomposite magnetic alloys with excellent magnetic properties by using much less RE elements.

关键词： Composite alloys High performance magnets Magnetic properties Alnico alloys Rare earth magnets

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Effectiveness of hybrid ensemble machine learning models for landslide susceptibility analysis:Evidence from Shimla district of North-west Indian Himalayan region

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Journal of Mountain Science 2024年第7期21卷 2368-2393页

作者： SHARMA Aastha sajjad Haroon RAHAMAN Md Hibjur SAHA Tamal Kanti BHUYAN Nirsobha Department of Geography Faculty of SciencesJamia Millia IslamiaNew Delhi-110025India

The Indian Himalayan region is frequently experiencing climate change-induced ***,landslide susceptibility assessment assumes greater significance for lessening the impact of a landslide *** paper makes an attempt to assess landslide susceptibility in Shimla district of the northwest Indian Himalayan *** examined the effectiveness of random forest(RF),multilayer perceptron(MLP),sequential minimal optimization regression(SMOreg)and bagging ensemble(B-RF,BSMOreg,B-MLP)models.A landslide inventory map comprising 1052 locations of past landslide occurrences was classified into training(70%)and testing(30%)*** site-specific influencing factors were selected by employing a multicollinearity *** relationship between past landslide occurrences and influencing factors was established using the frequency ratio *** effectiveness of machine learning models was verified through performance *** landslide susceptibility maps were validated by the area under the receiver operating characteristic curves(ROC-AUC),accuracy,precision,recall and *** key performance metrics and map validation demonstrated that the BRF model(correlation coefficient:0.988,mean absolute error:0.010,root mean square error:0.058,relative absolute error:2.964,ROC-AUC:0.947,accuracy:0.778,precision:0.819,recall:0.917 and F-1 score:0.865)outperformed the single classifiers and other bagging ensemble models for landslide *** results show that the largest area was found under the very high susceptibility zone(33.87%),followed by the low(27.30%),high(20.68%)and moderate(18.16%)susceptibility *** factors,namely average annual rainfall,slope,lithology,soil texture and earthquake magnitude have been identified as the influencing factors for very high landslide *** texture,lineament density and elevation have been attributed to high and moderate ***,the study calls for devising suitable landslide mitig

关键词： Landslide susceptibility Site-specific factors Machine learning models Hybrid ensemble learning Geospatial techniques Himalayan region

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Designing single atom catalysts for exceptional electrochemical CO_(2) reduction

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Chinese Journal of Structural Chemistry 2024年第1期43卷 3-5页

作者： Muhammad Humayun Mohamed Bououdina Abbas Khan sajjad Ali Chundong Wang Energy Water and Environment LabCollege of Humanities and SciencesPrince Sultan UniversityRiyadh11586Saudi Arabia School of Integrated Circuits Wuhan National Laboratory for OptoelectronicsHuazhong University of Science and TechnologyWuhan430074PR China Department of Chemistry Abdul Wali Khan University MardanMardan23200Pakistan

The release of anthropogenic CO_(2)emissions into the atmosphere has significantly accelerated global warming within the past few *** to the latest data,it is predicted that the concentration of CO_(2)will rise to 800 ppm over this century,and could reach 2000 ppm by *** high level of CO_(2)is expected to result in significant increase in global temperature as well as ocean acidification[1].

关键词： exceptional global release

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Simultaneously enhancing coercivity and remanence of hot-deformed Nd-Fe-B magnets by flake copper powder assisted DyF_(3) interflake addition

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Journal of Rare Earths 2024年第7期42卷 1282-1288,I0003页

作者： Yikuan Hu Jiajie Li Shengyu Sun Shuwei Zhong Munan Yang Xiaoqiang Yu sajjad Ur Rehman Xi Yu Jiangxi Key Laboratory for Rare Earth Magnetic Materials and Devices College of Rare EarthsJiangxi University of Science and TechnologyGanzhou341000 National Rare Earth Functional Materials Innovation Center Ganzhou341000China Ganzhou Fortune Electronic Ltd. Ganzhou341000China

It is still a challenge to simultaneously enhance coercivity(H_(cj))and remanence(J_(r))of hot-deformed Nd-Fe-B magnet due to the coercivity-remanence trade-off ***,we achieved this balance between H_(cj)and Jr by flake Cu powder assisted DyF_(3)interflake *** Hcj increases from 1218 to 1496 kA/m and Jr increases from 1.32 to 1.34 T compared with the original *** show that the width of coarse grain layers reduces because of the introduction of flake Cu,which increases the contact areas of the adjacent grains at ribbon interfaces and suppresses the excessive growth of *** stronger degree of texture and higher density compared with the original magnet should take the responsibility for the increase of J_(r).Additionally,the aggregation regions of rare earth rich(RE-rich)phase reduce and the betterment of the microstructure is another reason for the enhancement of Jr in the flake Cu aided DyF_(3)hot-deformed *** strategy of using flake powder additives provides a promising method for optimizing microstructure and enhancing magnetic properties of hot-deformed Nd-Fe-B magnets.

关键词： Rare earths Nd-Fe-B Hot-deformed magnet Flake powder Interflake addition Remanence

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Effects of lipids on the activity and structural dynamics of gamma secretase: A study using coarse-grained molecular dynamics simulations

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ChemPhysMater 2024年第3期3卷 303-313页

作者： Ahmad sajjad Jinfei Mei Chuanbo Wang Hongqi Ai School of Chemistry and Chemical Engineering University of JinanJinan 250022China

Gamma secretase(GS)is an intramembranous enzyme that acts on the amyloid precursor protein and Notch inside lipid *** enzyme is responsible for amyloid-𝛽propagation,one of the well-known causes of Alzheimer’s ***,the effects of lipids on GS activity and structural dynamics are ***,in this study,we performed coarse-grained molecular dynamics simulations to probe the effects of five individual lipids on *** lipids included 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine(POPE),1-palmitoyl2-oleoyl-sn-glycero-3-phosphocholine(POPC),1,2-dipalmitoyl-sn-phosphatidylcholine(DOPC),2-dimyristoyl-snglycero-3-phosphocholine(DMPC),and 1,2-dilauroyl-sn-glycero-3-phosphocholine(DLPC).These lipids are structurally characterized by different heads(i.e.,NH_(3)[PE]for POPE ***_(3)[PC]for POPC),number of double bonds(one for POPC *** for DOPC),and alkyl tail chain lengths(16:1/18:1 for DOPC vs.14:0/14:0 for DMPC vs.12:0/12:0 for DLPC).This indicates distinct microenvironments and adjustable structural elements for catalytic function when GS is *** results revealed that the presence of more unsaturated bonds in DOPC than in POPC resulted in greater GS ***,lipids with short alkyl tail chains or with PC heads instead of PE heads had improved mobility of the sixth transmembrane helix of GS,which is responsible for the considerable active site flexibility and presenilin 1 subunit *** length of the DMPC alkyl tail chain was between that of DOPC and DLPC because the up-down and cross-correlation motions of GS in DMPC was the lowest among the three lipids,and GS mobility in DMPC was the lowest among all five *** may be because the alkyl tail chain length(i.e.,3.8 nm thickness of the DMPC bilayer)was suitable for GS embedding,thereby restraining more GS motions than that of the long(DOPC)or short lipids(DLPC).Collectively,these results indicated that GS activity can be modulated through changes in con

关键词： Five lipids Gamma secretase Presenilin Nicastrin Effect of lipid on GS

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Fractal Fractional Order Operators in Computational Techniques for Mathematical Models in Epidemiology

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1385-1403页

作者： Muhammad Farman Ali Akgül Mir sajjad Hashemi Liliana Guran Amelia Bucur Institue of Mathematics Khwaja Fareed University of Enginnering and Information TechnologyRaheem Yar KhanPakistan Department of Computer Science and Mathematics Lebanese American UniversityBeirutLebanon Department of Mathematics Art and Science FacultySiirt UniversitySiirt56100Turkey Department of Mathematics Mathematics Research CenterNear East UniversityNicosiaTurkey Department of Computer Engineering Biruni UniversityIstanbul34010Turkey Department of Hospitality Services Babes-Bolyai UniversityCluj-Napoca400174Romania Department of Pharmaceutical Sciences Vasile Goldi竤Western University of AradArad310025Romania Department of Mathematics and Informatics Faculty of SciencesLucian Blaga University of SibiuSibiu550012Romania Department of Electronics and Communication Engineering Saveetha School of EngineeringSIMATSChennaiTamilnaduIndia

New fractional operators, the COVID-19 model has been studied in this paper. By using different numericaltechniques and the time fractional parameters, the mechanical characteristics of the fractional order model areidentified. The uniqueness and existence have been established. Themodel’sUlam-Hyers stability analysis has beenfound. In order to justify the theoretical results, numerical simulations are carried out for the presented methodin the range of fractional order to show the implications of fractional and fractal *** applied very effectivenumerical techniques to obtain the solutions of themodel and simulations. Also, we present conditions of existencefor a solution to the proposed epidemicmodel and to calculate the reproduction number in certain state conditionsof the analyzed dynamic system. COVID-19 fractional order model for the case of Wuhan, China, is offered foranalysis with simulations in order to determine the possible efficacy of Coronavirus disease transmission in theCommunity. For this reason, we employed the COVID-19 fractal fractional derivative model in the example ofWuhan, China, with the given beginning conditions. In conclusion, again the mathematical models with fractionaloperators can facilitate the improvement of decision-making for measures to be taken in the management of anepidemic situation.

关键词： COVID-19 model fractal-fractional operator Ulam-Hyers stability existence and uniqueness numerical simulation

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Effect of alumina and silica nanocomposite based on polyacrylamide on light and heavy oil recovery in presence of formation water using micromodel

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Petroleum 2024年第2期10卷 338-353页

作者： Ashkan Maleki Behnam Sedaee Alireza Bahramian sajjad Gharechelou Nahid Sarlak Arash Mehdizad Mohammad reza Rasaei Aliakbar Dehghan Science and Research Branch Islamic Azad UniversityIran Institute of Petroleum Engineering School of Chemical EngineeringUniversity of TehranIran School of Geology College of ScienceUniversity of TehranIran Department of Chemistry Lorestan University Iran Iranian Offshore Oil Company Iran

Increasing world request for energy has made oil extraction from reservoirs more *** novel EOR methods have been proposed and utilized for this *** nanocomposites in chemical flooding is one of these novel *** this study,we investigated the impact of six injection solutions on the recovery of light and heavy oil with the presence of two different brines as formation water using a homogenous glass *** of the injection solutions were based on a 40,000 ppm Na Cl synthetic seawater(SSW),one of which was additive free and the others were prepared by dispersing nanocomposite silica-based polyacrylamide(NCSP),nanocomposite alumina-based polyacrylamide(NCAP),the combination of both nanocomposites silica and alumina based on polyacrylamide(NCSAP),surfactant(CTAB)and polyacrylamide(PAM)with a concentration of 1000 ppm as *** Stability of nanocomposites was tested against the salinity of the brine and temperature using salinity and DSC tests which were *** stability tests,IFT,contact angle and oil recovery measurements were *** results revealed that in addition to the effect of silica and alumina nanocomposite in reducing interfacial tension and wettability alteration,control of mobility ratio caused a major improvement in sweeping efficiency and oil *** to the sweeping behavior of injected fluids,it was found that the main effect of surfactant was wettability alteration,for polyacrylamide was mobility control and for nanocomposites was the reduction of interfacial tension between oil and injected fluid,which was completely analyzed and checked ***,NCSAP with 95.83%and 70.33%and CTAB with 84.35%and 91%have the highest light oil recoveries at 250,000 ppm and 180,000 ppm salinity,respectively which is related to the superposition effect of interactions between nanocomposites,solution and *** on our results it can be concluded that the most effective mechanism in oil recovery was I

关键词： Enhanced oil recovery Micromodel Polyacrylamide Nanocomposite Salinity Alumina and silica nanoparticles

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