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Journal of Rare Earths 2012年第5期30卷 507-514页

作者： K.F.khan Shamim A.Dar saif a.khan Department of Geology Aligarh Muslim UniversityAligarh-202002Uttar PradeshIndia

The rare earth element（REE） data from the Paleoproterozoic Bijawar basin,Sonrai phosphorites were used to interpret the depositional conditions of the *** post archean Australian shales（PAAS） normalized REE patterns of the Sonrai phosphorites were characterized by negative Ce and positive Eu *** rare earth elements（MREE）-enrichment was a characteristic *** showing the diagenetic effects on the REE patterns were *** observed Eu anomaly was indicative of an anoxic（or sulphate reducing） diagenetic environment of phosphate *** of sea water and upwelling during the Paleoproterozoic was responsible for the recording of positive Eu and negative Ce anomalies in the Sonrai phosphorites.

关键词： rare earth elements geochemistry phosphorites Sonrai Bijawar basin Ce anomaly Eu anomaly

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Benchmarking the performance of Bayesian optimization across multiple experimental materials science domains

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npj Computational Materials 2021年第1期7卷 1742-1751页

作者： Qiaohao Liang Aldair E.Gongora Zekun Ren Armi Tiihonen Zhe Liu Shijing Sun James R.Deneault Daniil Bash Flore Mekki-Berrada saif a.khan Kedar Hippalgaonkar Benji Maruyama Keith A.Brown John Fisher III Tonio Buonassisi Massachusetts Institute of Technology CambridgeMAUnited States Boston University BostonMAUnited States Singapore-MIT Alliance for Research and Technology SingaporeSingapore Air Force Research Laboratory DaytonOhioUnited States Agency for Science Technology and Research(A*STAR)SingaporeSingapore National University of Singapore SingaporeSingapore Present address:Aalto University EspooFinland Present address:Northwestern Polytechincal University(NPU) Xi’anShaanxi P.R.China

Bayesian optimization(BO)has been leveraged for guiding autonomous and high-throughput experiments in materials ***,few have evaluated the efficiency of BO across a broad range of experimental materials *** this work,we quantify the performance of BO with a collection of surrogate model and acquisition function pairs across five diverse experimental materials *** defining acceleration and enhancement metrics for materials optimization objectives,we find that surrogate models such as Gaussian Process(GP)with anisotropic kernels and Random Forest(RF)have comparable performance in BO,and both outperform the commonly used GP with isotropic *** with anisotropic kernels has demonstrated the most robustness,yet RF is a close alternative and warrants more consideration because it is free from distribution assumptions,has smaller time complexity,and requires less effort in initial hyperparameter *** also raise awareness about the benefits of using GP with anisotropic kernels in future materials optimization campaigns.

关键词： optimization performance acceleration

Fractional synergetic tracking control for robot manipulator

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Journal of Control and Decision 2024年第1期11卷 139-152页

作者： Asma saif Raouf Fareh saif Sinan Maamar Bettayeb Department of Electrical Engineering University of SharjahSharjahUAE Department of Electrical Engineering École de technologie supérieureMontrealCanada CEIES King Abdulaziz UniversityJeddahSaudi Arabia

This work takes advantage of synergetic control theory and fractional calculus to develop and propose fractional synergetic control(FSC)strategy for Four Degrees of Freedom(4-DOF)robot *** proposed fractional synergetic control is designed to track a joint space as well as workspace desired *** calculus gives more flexibility in the design since it has a wider stability *** to that,as stated in the literature,compared to a similar approach such as sliding mode control,the synergetic control approach converges faster to the equilibrium point,without chattering with a fast *** paper proposes a new control strategy that takes advantage of fractional calculus and synergetic control *** proposed control strategy is tested experimentally on a 4-DOF manipulator to study the performance of the proposed control *** stability of the closed-loop system is proved using the Lyapunov *** experimental results have shown that the proposed FSC design has achieved a good tracking performance.

关键词： Synergetic control robust control robot manipulator fractional controller

Hydroelectric and Hydrogen Storage Systems for Electric Energy Produced from Renewable Energy Sources

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Energy Engineering 2024年第10期121卷 2719-2741页

作者： saif Serag Adil Echchelh Biagio Morrone Department of Engineering Universitàdella Campania“Luigi Vanvitelli”Aversa(CE)81031Italy Laboratory of Electronics Treatment Information Mechanic and EnergeticUniversity of Ibn TofailKenitra14000Morocco

Renewable energy sources are essential formitigating the greenhouse effect and supplying energy to resource-scarce ***,their intermittent nature necessitates efficient storage solutions to enhance system efficiency and manage energy *** paper investigates renewable and clean storage systems,specifically examining the storage of electricity generated from renewable sources using hydropower plants and hydrogen,both of which are highly efficient and promising for future energy production and *** study utilizes extensive literature data to analyze the impact of various parameters on the cost per kWh of electricity production in hybrid renewable systems incorporating hydropower and hydrogen storage *** indicate that these hybrid systems can store electricity efficiently and cost-effectively,with production costs ranging from 0.126 to 0.3$/kWh for renewablehydropower systems and 0.118 to 0.42$/kWh for renewable-hydrogen systems,with expected cost reductions over the next decade due to technological advancements and increased market *** novelty of this study lies in its comprehensive comparison of hybrid renewable systems integrating hydropower and hydrogen storage,providing detailed cost analysis and future *** identifies key parameters influencing the cost and efficiency of these systems,offering insights into optimizing storage solutions for renewable ***,this research underscores the potential of hybrid systems to reduce dependency on fossil fuels,particularly during peak demand periods,and emphasizes the importance of seasonal and geographic considerations in selecting energy *** study highlights the importance of policy support and investment in hybrid renewable systems and calls for further research into optimizing these systems for different seasonal and geographic ***,the integration of renewable energy sources with hydropower and hydrogen storage offers a promising pathwa

关键词： Energy storage hydropower hydrogen renewable energy hybrid system

Is atmospheric pathway a significant contributor to microplastics in the marine environment?

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Emerging Contaminants 2024年第2期10卷 26-32页

作者： Nazima Habibi saif Uddin Montaha Behbehani Jin-Yong Lee Environment and Life Sciences Research Center Kuwait Institute for Scientific ResearchKuwait Department of Geology Kangwon National UniversityChuncheon24341Republic of Korea

Transmission of microplastics(MPs)through aerosolization has been recently realized as an important *** of the reports of the ubiquitous MP presence in aerosols,the spatio-temporal information is inadequate and has very limited practicality in assessing if aerosol can be a significant source of MPs to the marine *** on marine contribution to atmospheric MPs is exceptionally scarce,and the ocean-air exchange is considered an emerging research *** of MPs entering the oceans via atmospheric deposition has been recently *** idea of ocean-air exchange emanates from the fact that beach sediments can get suspended under sand and dust storms,bubble bursts and sea sprays due to wind and waves in surf zones can lead to the ejection of particles into *** this succinct review,we have tried compiling the data on atmospheric MPs that can shed some light on the flux from and to the aquatic *** the information is too limited never the less its incorporation into the marine MP cycle cannot be neglected.

关键词： Marine-atmospheric flux Aerosols Microplastics MP load MP inventories

Linkages among leaf nutrient concentration,resorption efficiency, litter decomposition and their stoichiometry to canopy nitrogen addition and understory removal in subtropical plantation

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Ecological Processes 2024年第2期13卷 90-102页

作者： Jawad Ali Shah Wenfei Liu saif Ullah Honglang Duan Fangfang Shen Yingchun Liao Guomin Huang Jianping Wu Ministry of Education Key Laboratory for Transboundary Ecosecurity of Southwest China Yunnan Key Laboratory of Plant Reproductive Adaptation and Evolutionary Ecology and Institute of Biodiversity School of Ecology and Environmental Science Yunnan University Laboratory of Soil Ecology and Health in Universities of Yunnan Province Yunnan University Jiangxi Key Laboratory for Restoration of Degraded Ecosystems & Watershed Ecohydrology Nanchang Institute of Technology Key Laboratory of Forest Cultivation in Plateau Mountain of Guizhou Province Institute for Forest Resources and Environment of Guizhou College of ForestryGuizhou University

Background The prevalence of understory removal and anthropogenic nitrogen(N) deposition has significantly altered the ecological processes of forest ecosystems at both regional and global scales. However, it remains a pressing challenge to understand how N deposition and understory removal affect leaf nutrient dynamics, nutrient resorption, litter decomposition, and their linkages for better managing forest ecosystems under nutrient imbalances induced by N enrichment. To address this research gap, a field manipulation experiment was carried out in a subtropical Cunninghamia lanceolata plantation with four treatments including: control(CK), canopy N addition(CN), understory removal(UR), and canopy N addition plus understory removal(CN × UR). Green and senesced leaf N and phosphorus(P) concentrations, N and P resorption efficiencies, litter decomposition, and their correlations were *** The results revealed that the average N concentrations of green early and late leaves in UR were increased by 6.61 and 18.89% compared to CK. UR had the highest whereas CN had the lowest P concentrations in green leaves across the two sampling seasons. Following this, UR, leaf type, season, and their interactions significantly affected leaf N, P, and N:P(P < 0.05). The highest leaf N resorption(32.68%) and P resorption efficiencies(63.96%) were recorded in UR. Litter decomposition was significantly retarded in UR(P < 0.01) relative to CN. The regression analysis demonstrated that leaf nutrient status was significantly interconnected with leaf nutrient resorption efficiencies. In addition, leaf nutrient dynamics were strongly correlated with litter nutrients, indicating that both were *** These findings can deepen our knowledge of biogeochemical cycling and reveal contrasting nutrientacquisition strategies on N and P limitation in response to UR and CN. Considering the P limitation, it is important to note that P was resorbed more efficiently, illustrating a

关键词： Nutrient resorption Nitrogen deposition Litter decomposition Stoichiometry Understory removal Subtropical plantation

Beyond bacteria:Role of non-bacterial gut microbiota species in inflammatory bowel disease and colorectal cancer progression

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World Journal of Gastroenterology 2024年第36期30卷 4078-4082页

作者： Hania Haque Syeda Warisha Zehra Mohammad Shahzaib saif Abbas Nazish Jaffar of Medicine Jinnah Sindh Medical UniversityKarachi 75510SindhPakistan Department of Pathology Jinnah Sindh Medical UniversityKarachi 75510SindhPakistan

This letter emphasizes the need to expand discussions on gut microbiome’s role in inflammatory bowel disease(IBD)and colorectal cancer(CRC)by including the often-overlooked non-bacterial components of the human gut *** highlights how viral,fungal and archaeal inhabitants of the gut respond towards gut dysbiosis and contribute to disease *** such as bacteriophages target certain bacterial species and modulate the immune *** viruses found associated include Epstein-Barr virus,human papillomavirus,John Cunningham virus,cytomegalovirus,and human herpes simplex virus type *** such as Candida albicans and Malassezia contribute by forming tissue-invasive filaments and producing inflammatory cytokines,***,mainly methanogens are also found altering the microbial fermentation *** correspondence,thus underscores the significance of considering the pathological and physiological mechanisms of the entire spectrum of the gut microbiota to develop effective therapeutic interventions for both IBD and CRC.

关键词： Gut microbiota Colorectal cancer Inflammatory bowel disease Dysbiosis Bacteriophages Methanogens Fungi

Luminescence regulation of Sb^(3+)in 0D hybrid metal halides by hydrogen bond network for optical anti-counterfeiting

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Opto-Electronic Advances 2024年第3期7卷 15-25页

作者： Dehai Liang saif M.H.Qaid Xin Yang Shuangyi Zhao Binbin Luo Wensi Cai Qingkai Qian Zhigang Zang Key Laboratory of Optoelectronic Technology&Systems(Ministry of Education) Chongqing UniversityChongqing 400044China Department of Physics&Astronomy College of SciencesKing Saud UniversityP.O.Box 2455Riyadh 11451Saudi Arabia Department of Chemistry and Chemical Engineering Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong ProvinceShantou UniversityShantou 515063China Department of Oil Army Logistics Academy of PLAChongqing 401311China

The Sb^(3+) doping strategy has been proven to be an effective way to regulate the band gap and improve the photophysical properties of organic-inorganic hybrid metal halides(OIHMHs).However,the emission of Sb^(3+) ions in OIHMHs is primarily confined to the low energy region,resulting in yellow or red *** date,there are few reports about green emission of Sb^(3+)-doped ***,we present a novel approach for regulating the luminescence of Sb^(3+) ions in 0D C_(10)H_(2)_(2)N_(6)InCl_(7)·H_(2)O via hydrogen bond network,in which water molecules act as agents for hydrogen ***^(3+)-doped C_(10)H_(2)2N_(6)InCl_(7)·H_(2)O shows a broadband green emission peaking at 540 nm and a high photoluminescence quantum yield(PLQY)of 80%.It is found that the intense green emission stems from the radiative recombination of the self-trapped excitons(STEs).Upon removal of water molecules with heat,C_(10)H_(2)_(2)N_(6)In_(1-x)Sb_(x)Cl_(7) generates yellow emis-sion,attributed to the breaking of the hydrogen bond network and large structural distortions of excited *** water molecules are adsorbed by C_(10)H_(2)_(2)N_(6)In_(1-x)Sb_(x)Cl_(7),it can subsequently emit green *** water-induced reversible emission switching is successfully used for optical security and information *** findings expand the under-standing of how the local coordination structure influences the photophysical mechanism in Sb^(3+)-doped metal halides and provide a novel method to control the STEs emission.

关键词： indium-based halides Sb^(3+)doping hydrogen bonding network optical anti-counterfeiting

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Artificial Intelligence Prediction of One-Part Geopolymer Compressive Strength for Sustainable Concrete

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 525-543页

作者： Mohamed Abdel-Mongy Mudassir Iqbal M.Farag Ahmed.M.Yosri Fahad Alsharari saif Eldeen A.S.Yousef Department of Civil Engineering College of EngineeringJouf UniversitySakaka72388Saudi Arabia Department of Civil Engineering University of Engineering and TechnologyPeshawar54890Pakistan Civil Engineering Department Faculty of EngineeringAl-Azhar UniversityCairo11884Egypt Civil Engineering Department Faculty of EngineeringAswan UniversityAswan81528Egypt

Alkali-activated materials/geopolymer(AAMs),due to their low carbon emission content,have been the focus of recent studies on ecological *** terms of performance,fly ash and slag are preferredmaterials for precursors for developing a one-part ***,determining the optimum content of the input parameters to obtain adequate performance is quite challenging and scarcely ***,in this study,machine learning methods such as artificial neural networks(ANN)and gene expression programming(GEP)models were developed usingMATLAB and GeneXprotools,respectively,for the prediction of compressive strength under variable input materials and content for fly ash and slag-based one-part *** database for this study contains 171 points extracted from literature with input parameters:fly ash concentration,slag content,calcium hydroxide content,sodium oxide dose,water binder ratio,and curing *** performance of the two models was evaluated under various statistical indices,namely correlation coefficient(R),mean absolute error(MAE),and rootmean square error(RMSE).In terms of the strength prediction efficacy of a one-part geopolymer,ANN outperformed *** and parametric analysis were also performed to identify the significant contributor to *** to a sensitivity analysis,the activator and slag contents had the most effects on the compressive strength at 28 *** water binder ratio was shown to be directly connected to activator percentage,slag percentage,and calcium hydroxide percentage and inversely related to compressive strength at 28 days and curing temperature.

关键词： Artificial intelligence techniques one-part geopolymer artificial neural network gene expression modelling sustainable construction polymers

Acute pancreatitis:pathogenesis and emerging therapies

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Journal of Pancreatology 2024年第1期7卷 10-20页

作者： saif Zaman Fred Gorelick Department of Internal Medicine Yale School of MedicineNew HavenCT 06511 Veteran’s Administration Healthcare System West HavenCT 06516 Department of Cell Biology Yale School of MedicineNew HavenCT 06511

Acute pancreatitis is a severe inflammatory disorder with limited treatment *** understanding of disease mechanisms has led to new and potential *** we summarize what we view as some of the most promising new therapies for treating acute pancreatitis,emphasizing the rationale of specific treatments based on disease *** pharmacologic interventions are *** explore potential treatment benefits and risks concerning reducing acute injury,minimizing complications,and improving long-term *** associated with acute pancreatitis initiation,perpetuation,and reconstitution are highlighted,along with potential therapeutic targets and how these relate to new treatments.

关键词： Acinar cell Acute pancreatitis Calcium signaling Transporters Treatment

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