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Straw return increases crop production by improving soil organic carbon sequestration and soil aggregation in a long-term wheat-cotton cropping system 被引量:2
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作者 Changqin Yang Xiaojing Wang +6 位作者 Jianan Li Guowei Zhang Hongmei Shu Wei Hu Huanyong Han Ruixian Liu Zichun Guo 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期669-679,共11页
Straw return is a promising strategy for managing soil organic carbon(SOC)and improving yield stability.However,the optimal straw return strategy for sustainable crop production in the wheat(Triticum aestivum L.)-cott... Straw return is a promising strategy for managing soil organic carbon(SOC)and improving yield stability.However,the optimal straw return strategy for sustainable crop production in the wheat(Triticum aestivum L.)-cotton(Gossypium hirsutum L.)cropping system remains uncertain.The objective of this study was to quantify the long-term(10 years)impact of carbon(C)input on SOC sequestration,soil aggregation and crop yields in a wheat-cotton cropping system in the Yangtze River Valley,China.Five treatments were arranged with a single-factor randomized design as follows:no straw return(Control),return of wheat straw only(Wt),return of cotton straw only(Ct),return of 50%wheat and 50%cotton straw(Wh-Ch)and return of 100%wheat and 100%cotton straw(Wt-Ct).In comparison to the Control,the SOC content increased by 8.4 to 20.2%under straw return.A significant linear positive correlation between SOC sequestration and C input(1.42-7.19 Mg ha^(−1)yr^(−1))(P<0.05)was detected.The percentages of aggregates of sizes>2 and 1-2 mm at the 0-20 cm soil depth were also significantly elevated under straw return,with the greatest increase of the aggregate stability in the Wt-Ct treatment(28.1%).The average wheat yields increased by 12.4-36.0%and cotton yields increased by 29.4-73.7%,and significantly linear positive correlations were also detected between C input and the yields of wheat and cotton.The average sustainable yield index(SYI)reached a maximum value of 0.69 when the C input was 7.08 Mg ha^(−1)yr^(−1),which was close to the maximum value(SYI of 0.69,C input of 7.19 Mg ha^(−1)yr^(-1))in the Wt-Ct treatment.Overall,the return of both wheat and cotton straw was the best strategy for improving SOC sequestration,soil aggregation,yields and their sustainability in the wheat-cotton rotation system. 展开更多
关键词 straw return crop yields SOC soil aggregates wheat-cotton cropping system
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A novel approach to Parkinson's disease treatment with a potentially dual-acting therapeutic agent that targetsα-synuclein aggregation and neuron death 被引量:1
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作者 Allison RBalaj Hiroaki Kaku 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第12期2577-2578,共2页
Parkinson's disease(PD),a prevalent neurodegenerative disorder,is chara cterized by the loss of dopaminergic neurons and the aggregation ofα-synuclein protein into Lewy bodies.While the current standards of thera... Parkinson's disease(PD),a prevalent neurodegenerative disorder,is chara cterized by the loss of dopaminergic neurons and the aggregation ofα-synuclein protein into Lewy bodies.While the current standards of therapy have been successful in providing some symptom relief,they fail to address the underlying pathophysiology of PD and as a result,they have no effect on disease progression. 展开更多
关键词 aggregATION DEATH THERAPEUTIC
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RBC aggregation,deformation and adhesion to endothelium:Role of nitric oxide derived from L-Arginine and sodium nitroprusside 被引量:1
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作者 M.K.Maksimov P.B.Ermolinskiy +4 位作者 O.N.Scheglovitova N.N.Sklyankina A.V.Muravyov A.E.Lugovtsov A.V.Priezzhev 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第5期53-65,共13页
Red blood cells(RBCs)are the most abundant human blood cells.RBC aggregation and deformation strongly determine blood viscosity which impacts hemorheology and microcirculation.In turn,RBC properties depend on di®... Red blood cells(RBCs)are the most abundant human blood cells.RBC aggregation and deformation strongly determine blood viscosity which impacts hemorheology and microcirculation.In turn,RBC properties depend on di®erent endogenous and exogenous factors.One such factor is nitric oxide(NO),which is mainly produced by endothelial cells(EC)from L-arginine amino acid in the circulatory system.Since the mechanisms of the RBC-endothelium interplay are not clear up to date and considering its possible clinical importance,the aims of this study are to investigate in vitro:(1)The effect of L-arginine induced NO on RBC aggregation and adhesion to endothelium;(2)the NO e®ect on RBC aggregation and deformation induced by L-arginine and sodium nitroprusside without the presence of endothelium in the samples.The RBC aggregation and adhesion to a monolayer of EC were studied using optical tweezers(OT).The RBC deformability and aggregation without endothelium in the samples were studied using the flow chamber method and Myrenne aggregometer.We confirmed that NO increases deformability and decreases aggregation of RBCs.We showed that the soluble guanylate cyclase pathway appears to be the only NO signaling pathway involved.In the samples with the endothelium,the "bell-shaped"dependence of RBC aggregation force on L-arginine concentration was observed,which improves our knowledge about the process of NO production by endothelium.Additionally,data related to L-arginine accumulation by endothelium were obtained:Necessity of the presence of extracellular L-arginine stated by other authors was put under question.In our study,NO decreased the RBC-endothelium adhesion,however,the tendency appeared to be weak and was not confirmed in another set of experiments.To our knowledge,this is the first attempt to measure the forces of RBC adhesion to endothelium monolayer with OT. 展开更多
关键词 Red blood cells aggregATION L-ARGININE ENDOTHELIUM optical tweezers Myrenne flow chamber
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Impacts of Aggregation Methods and Trophospecies Number on the Structure and Function of Marine Food Webs
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作者 LI Pengcheng ZHANG Chongliang +4 位作者 XU Binduo JI Yupeng LI Fan REN Yiping XUE Ying 《Journal of Ocean University of China》 CAS CSCD 2024年第1期190-198,共9页
Aggregation of species with similar ecological properties is one of the effective methods to simplify food web researches.However,species aggregation will affect not only the complexity of modeling process but also th... Aggregation of species with similar ecological properties is one of the effective methods to simplify food web researches.However,species aggregation will affect not only the complexity of modeling process but also the accuracy of models’outputs.Selection of aggregation methods and the number of trophospecies are the keys to study the simplification of food web.In this study,three aggregation methods,including taxonomic aggregation(TA),structural equivalence aggregation(SEA),and self-organizing maps(SOM),were analyzed and compared with the linear inverse model–Markov Chain Monte Carlo(LIM-MCMC)model.Impacts of aggregation methods and trophospecies number on food webs were evaluated based on the robustness and unitless of ecological net-work indices.Results showed that aggregation method of SEA performed better than the other two methods in estimating food web structure and function indices.The effects of aggregation methods were driven by the differences in species aggregation principles,which will alter food web structure and function through the redistribution of energy flow.According to the results of mean absolute percentage error(MAPE)which can be applied to evaluate the accuracy of the model,we found that MAPE in food web indices will increase with the reducing trophospecies number,and MAPE in food web function indices were smaller and more stable than those in food web structure indices.Therefore,trade-off between simplifying food webs and reflecting the status of ecosystem should be con-sidered in food web studies.These findings highlight the importance of aggregation methods and trophospecies number in the analy-sis of food web simplification.This study provided a framework to explore the extent to which food web models are affected by dif-ferent species aggregation,and will provide scientific basis for the construction of food webs. 展开更多
关键词 LIM-MCMC model species aggregation trophospecies number aggregation methods food web indices
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Effect of Aggregate Gradation on the Properties of 3D Printed Recycled Coarse Aggregate Concrete
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作者 DING Yahong TONG Jiaqi +3 位作者 ZHANG Meixiang GUO Shuqi ZHANG Yaqi ZHAO Yu 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第6期1541-1554,共14页
A simplex centroid design method was employed to design the gradation of recycled coarse aggregate.The bulk density was measured while the specific surface area and average excess paste thickness were calculated with ... A simplex centroid design method was employed to design the gradation of recycled coarse aggregate.The bulk density was measured while the specific surface area and average excess paste thickness were calculated with different gradations.The fluidity,dynamic yield stress,static yield stress,printed width,printed inclination,compressive strength and ultrasonic wave velocity of 3D printed recycled aggregate concrete(3DPRAC)were further studied.The experimental results demonstrate that,with the increase of small-sized aggregate(4.75-7 mm)content,the bulk density initially increases and then decreases,and the specific surface area gradually increases.The average excess paste thickness fluctuates with both bulk density and specific surface area.The workability of 3DPRAC is closely related to the average excess paste thickness.With an increase in average paste thickness,there is a gradual decrease in dynamic yield stress,static yield stress and printed inclination,accompanied by an increase in fluidity and printed width.The mechanical performance of 3DPRAC closely correlates with the bulk density.With an increase in the bulk density,there is an increase in the ultrasonic wave velocity,accompanied by a slight increase in the compressive strength and a significant decrease in the anisotropic coefficient.Furthermore,an index for buildability failure of 3DPRAC based on the average excess paste thickness is proposed. 展开更多
关键词 3D printed recycled coarse aggregate concrete aggregate gradation excess paste WORKABILITY mechanical performance
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Underwater Pulse Waveform Recognition Based on Hash Aggregate Discriminant Network
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作者 WANG Fangchen ZHONG Guoqiang WANG Liang 《Journal of Ocean University of China》 SCIE CAS CSCD 2024年第3期654-660,共7页
Underwater pulse waveform recognition is an important method for underwater object detection.Most existing works focus on the application of traditional pattern recognition methods,which ignore the time-and space-vary... Underwater pulse waveform recognition is an important method for underwater object detection.Most existing works focus on the application of traditional pattern recognition methods,which ignore the time-and space-varying characteristics in sound propagation channels and cannot easily extract valuable waveform features.Sound propagation channels in seawater are time-and space-varying convolutional channels.In the extraction of the waveform features of underwater acoustic signals,the effect of high-accuracy underwater acoustic signal recognition is identified by eliminating the influence of time-and space-varying convolutional channels to the greatest extent possible.We propose a hash aggregate discriminative network(HADN),which combines hash learning and deep learning to minimize the time-and space-varying effects on convolutional channels and adaptively learns effective underwater waveform features to achieve high-accuracy underwater pulse waveform recognition.In the extraction of the hash features of acoustic signals,a discrete constraint between clusters within a hash feature class is introduced.This constraint can ensure that the influence of convolutional channels on hash features is minimized.In addition,we design a new loss function called aggregate discriminative loss(AD-loss).The use of AD-loss and softmax-loss can increase the discriminativeness of the learned hash features.Experimental results show that on pool and ocean datasets,which were collected in pools and oceans,respectively,by using acoustic collectors,the proposed HADN performs better than other comparative models in terms of accuracy and mAP. 展开更多
关键词 convolutional channel hash aggregate discriminative network aggregate discriminant loss waveform recognition
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Small molecules to target tau amyloid aggregation
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作者 Zoe Manglano-Artuñedo Samuel Peña-Díaz Salvador Ventura 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第3期509-511,共3页
Protein aggregation has been linked with many neurodegenerative diseases,such as Alzheimer’s disease(AD)or Parkinson’s disease.AD belongs to a group of heterogeneous and incurable neurodegenerative disorders collect... Protein aggregation has been linked with many neurodegenerative diseases,such as Alzheimer’s disease(AD)or Parkinson’s disease.AD belongs to a group of heterogeneous and incurable neurodegenerative disorders collectively known as tauopathies.They comprise frontotemporal dementia,Pick’s disease,or corticobasal degeneration,among others.The symptomatology varies with the specific tau protein variant involved and the affected brain region or cell type.However,they share a common neuropathological hallmark-the formation of proteinaceous deposits named neurofibrillary tangles.Neurofibrillary tangles,primarily composed of aggregated tau(Zhang et al.,2022),disrupt normal neuronal functions,leading to cell death and cognitive decline. 展开更多
关键词 TAU DEGENERATION aggregATION
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Aggregation-regulated bioreduction process of graphene oxide by Shewanella bacteria
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作者 Kaixin Han Yibo Zeng +2 位作者 Yinghua Lu Ping Zeng Liang Shen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期56-62,共7页
The bioreduction of graphene oxide(GO)using environmentally functional bacteria such as Shewanella represents a green approach to produce reduced graphene oxide(rGO).This process differs from the chemical reduction th... The bioreduction of graphene oxide(GO)using environmentally functional bacteria such as Shewanella represents a green approach to produce reduced graphene oxide(rGO).This process differs from the chemical reduction that involves instantaneous molecular reactions.In bioreduction,the contact of bacterial cells and GO is considered the rate-limiting step.To reveal how the bacteria-GO integration regulates rGO production,the comparative experiments of GO and three Shewanella strains were carried out.Fourier-transform infrared spectroscopy,X-ray photoelectron spectroscopy,Raman spectroscopy,and atomic force microscopy were used to characterize the reduction degree and the aggregation degree.The results showed that a spontaneous aggregation of GO and Shewanella into the condensed entity occurred within 36 h.A positive linear correlation was established,linking three indexes of the aggregation potential,the bacterial reduction ability,and the reduction degree(ID/IG)comprehensively. 展开更多
关键词 Graphene oxide Reduced graphene oxide BIOREDUCTION aggregATION SHEWANELLA
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Clinical significance of platelet mononuclear cell aggregates in patients with sepsis and acute respiratory distress syndrome
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作者 Chong-Min Huang Juan-Juan Li Wei-Ke Wei 《World Journal of Clinical Cases》 SCIE 2024年第5期966-972,共7页
BACKGROUND The diagnosis of sepsis combined with acute respiratory distress syndrome(ARDS)has increased owing to the enhanced awareness among medical profes-sionals and the continuous development of modern medical tec... BACKGROUND The diagnosis of sepsis combined with acute respiratory distress syndrome(ARDS)has increased owing to the enhanced awareness among medical profes-sionals and the continuous development of modern medical technologies,while early diagnosis of ARDS still lacks specific biomarkers.One of the main patho-genic mechanisms of sepsis-associated ARDS involves the actions of various pathological injuries and inflammatory factors,such as platelet and white blood cells activation,leading to an increase of surface adhesion molecules.These adhesion molecules further form platelet-white blood cell aggregates,including platelet-mononuclear cell aggregates(PMAs).PMAs has been identified as one of the markers of platelet activation,here we hypothesize that PMAs might play a potential biomarker for the early diagnosis of this complication.METHODS We selected 72 hospitalized patients diagnosed with sepsis as the study population between March 2019 and March 2022.Among them,30 patients with sepsis and ARDS formed the study group,while 42 sepsis patients without ARDS comprised the control group.After diagnosis,venous blood samples were imme-diately collected from all patients.Flow cytometry was employed to analyze the expression of PMAs,platelet neutrophil aggregates(PNAs),and platelet aggregates(PLyAs)in the serum.Additionally,the Acute Physiology and Chronic Health Evaluation(APACHE)II score was calculated for each patient,and receiver operating characteristic curves were generated to assess diagnostic value.RESULTS The study found that the levels of PNAs and PLyAs in the serum of the study group were higher than those in the control group,but the difference was not statistically significant(P>0.05).However,the expression of PMAs in the serum of the study group was significantly upregulated(P<0.05)and positively correlated with the APACHE II score(r=0.671,P<0.05).When using PMAs as a diagnostic indicator,the area under the curve value was 0.957,indicating a high diagnostic value(P<0.05).Furthermore,the optimal cutoff value was 8.418%,with a diagnostic sensitivity of 0.819 and specificity of 0.947.CONCLUSION In summary,the serum levels of PMAs significantly increase in patients with sepsis and ARDS.Therefore,serum PMAs have the potential to become a new biomarker for clinically diagnosing sepsis complicated by ARDS. 展开更多
关键词 SEPSIS Acute respiratory distress syndrome Platelet leukocyte aggregates Platelet mononuclear cell aggregates Biomarker
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Mechanical Behavior Based on Aggregates Microstructure of Ultra-high Performance Concrete
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作者 丁庆军 ZHOU Changsheng +4 位作者 张高展 GUO Hong LI Yang ZHANG Yongyuan GUO Kaizheng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第3期673-681,共9页
We developed ultra-high performance concrete(UHPC)incorporating mullite sand and brown corundum sand(BCS),and the quartz sand UHPC was utilized to prepare for comparison.The properties of compressive strength,elastic ... We developed ultra-high performance concrete(UHPC)incorporating mullite sand and brown corundum sand(BCS),and the quartz sand UHPC was utilized to prepare for comparison.The properties of compressive strength,elastic modulus,ultrasonic pulse velocity,flexural strength,and toughness were investigated.Scanning electron microscopy and nanoindentation were also conducted to reveal the underlying mechanisms affecting macroscopic performance.Due to the superior interface bonding properties between mullite sand and matrix,the compressive strength and flexural toughness of UHPC have been significantly improved.Mullite sand and BCS aggregates have higher stiffness than quartz sand,contributing to the excellent elastic modulus exhibited by UHPC.The stiffness and volume of aggregates have a more significant impact on the elastic modulus of UHPC than interface performance,and the latter contributes more to the strength of UHPC.This study will provide a reference for developing UHPC with superior elastic modulus for structural engineering. 展开更多
关键词 ultra-high performance concrete mechanical properties fine aggregates MICROSTRUCTURE NANOINDENTATION
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The Mechanical and Electrical Properties of the Smart Aggregate Based on the Mixed Cementitious Materials
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作者 WANG Haifeng YAN Handong +2 位作者 XU Yuye MEI Zhen WANG Chen 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第6期1528-1533,共6页
Cement and resin were designed as mixed cementitious materials to study the smart aggregate(SA)of smart concrete.Carbon fiber(CF)and surfactant were taken into consideration to adjust the mechanical and electrical pro... Cement and resin were designed as mixed cementitious materials to study the smart aggregate(SA)of smart concrete.Carbon fiber(CF)and surfactant were taken into consideration to adjust the mechanical and electrical properties of smart aggregate(SA)in this issue.The experimental results indicate that the flexibility and mechanical properties of SA can be improved by using such mixed cementitious materials.It is shows that,although the compressive strength and flexural strength can be enhanced effectively by using resin and CF,the electrical conductivity decreases significantly,which is because the water molecules are difficult to penetrate through the mixture materials so the hydration reaction of cement can not fully carry out.However,the electrical conductivity can be improved by adding the surfactant,and the strength and mechanical electrical properties can be adjusted effectively by the surfactant. 展开更多
关键词 SURFACTANT carbon fiber electrical property mechanical property smart aggregate
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Straw mulching alters the composition and loss of dissolved organic matter in farmland surface runoff by inhibiting the fragmentation of soil small macroaggregates
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作者 Shanshan Cai Lei Sun +7 位作者 Wei Wang Yan Li Jianli Ding Liang Jin Yumei Li Jiuming Zhang Jingkuan Wang Dan Wei 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1703-1717,共15页
Straw mulching is a widespread practice for reducing the soil carbon loss caused by erosion.However,the effects of straw mulching on dissolved organic matter(DOM)runoff loss from black soil are not well studied.How st... Straw mulching is a widespread practice for reducing the soil carbon loss caused by erosion.However,the effects of straw mulching on dissolved organic matter(DOM)runoff loss from black soil are not well studied.How straw mulching affects the composition and loss of runoff DOM by changing soil aggregates remains largely unclear.Here,a straw mulching treatment was compared to a no mulching treatment(as a control)on sloping farmland with black soil erosion in Northeast China.We divided the soil into large macroaggregates(>2 mm),small macroaggregates(0.25-2 mm),and microaggregates(<0.25 mm).After five rain events,the effects of straw mulching on the concentration(characterized by dissolved organic carbon(DoC)and composition(analyzed by fluorescence spectroscopy)of runoff and soil aggregate DOM were studied.The results showed that straw mulching reduced the runoff amount by 54.7%.Therefore,although straw mulching increased the average DOc concentration in runoff,it reduced the total runoff DOM loss by 48.3%.The composition of runoff DOM is similar to that of soil,as both contain humic-like acid and protein-like components.With straw mulching treatment,the protein-like components in small macroaggregates accumulated and the protein-like components in runoff declined with rain events.Fluorescence spectroscopy technology may help in understanding the hydrological paths of rain events by capturing the dynamic changes of runoff and soil DOM characteristics.A variation partitioning analysis(VPA)indicated that the DOM concentration and composition of microaggregates explained 68.2%of the change in runoff DOM from no mulching plots,while the change in runoff DOM from straw mulching plots was dominated by small macroaggregates at a rate of 55.1%.Taken together,our results demonstrated that straw mulching reduces the fragmentation of small macroaggregates and the loss of microaggregates,thus effecting DOM compositions in soil and reducing the DOM loss in runoff.These results provide a theoretical basis for reducing carbon loss in sloping farmland. 展开更多
关键词 dissolved organic matter black soil surface runoff aggregATES fluorescence spectrum
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Online identification and extraction method of regional large-scale adjustable load-aggregation characteristics
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作者 Siwei Li Liang Yue +1 位作者 Xiangyu Kong Chengshan Wang 《Global Energy Interconnection》 EI CSCD 2024年第3期313-323,共11页
This article introduces the concept of load aggregation,which involves a comprehensive analysis of loads to acquire their external characteristics for the purpose of modeling and analyzing power systems.The online ide... This article introduces the concept of load aggregation,which involves a comprehensive analysis of loads to acquire their external characteristics for the purpose of modeling and analyzing power systems.The online identification method is a computer-involved approach for data collection,processing,and system identification,commonly used for adaptive control and prediction.This paper proposes a method for dynamically aggregating large-scale adjustable loads to support high proportions of new energy integration,aiming to study the aggregation characteristics of regional large-scale adjustable loads using online identification techniques and feature extraction methods.The experiment selected 300 central air conditioners as the research subject and analyzed their regulation characteristics,economic efficiency,and comfort.The experimental results show that as the adjustment time of the air conditioner increases from 5 minutes to 35 minutes,the stable adjustment quantity during the adjustment period decreases from 28.46 to 3.57,indicating that air conditioning loads can be controlled over a long period and have better adjustment effects in the short term.Overall,the experimental results of this paper demonstrate that analyzing the aggregation characteristics of regional large-scale adjustable loads using online identification techniques and feature extraction algorithms is effective. 展开更多
关键词 Load aggregation Regional large-scale Online recognition Feature extraction method
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Polycrystalline ZSM-5 Aggregates Induced by Seed and Catalytic Performance in Methanol to Hydrocarbon
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作者 WANG Xuchang JIAO Chuyu +5 位作者 JI Zhuo JIAO Qirui QIN Bo DU Yanze ZHENG Jiajun LI Ruifeng 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2024年第8期945-954,I0010-I0013,共14页
Synthesis of ZSM-5 zeolite typically utilizes small molecule polyamines or quaternary ammonium salts as organic structure guiding agent(OSDA).By contrast,the OSDA-free hydrothermal synthesis system eliminates the use ... Synthesis of ZSM-5 zeolite typically utilizes small molecule polyamines or quaternary ammonium salts as organic structure guiding agent(OSDA).By contrast,the OSDA-free hydrothermal synthesis system eliminates the use of organic templates and the subsequent calcination procedure.This not only reduces the cost of synthesis,but also prevents environmental pollution from the combustion of organic templates,representing an eco-friendly approach.Despite this,literature suggests that even so-called template-free synthesis systems often involve trace amount of organic substances like alcohol.In the present work,a calcined commercial ZSM-5 zeolite was served as seed,with sodium aluminate as aluminum source and silica sol as silicon source,ensuring an entirely template-free synthesis system.Polycrystalline ZSM-5 aggregates consisted of rod-like nanocrystals were successfully prepared in the completely OSDA-free system.Effects of the Si/Al ratio in ZSM-5 seed,dosage and crystallization conditions such as crystallization temperature and crystallization time on ZSM-5 synthesis were investigated.The results show that a highly crystallinity ZSM-5 aggregate consisting of primary nano-sized crystals less than 100 nm is produced from a gel precursor with 5.6%(in mass)seed after hydrothermal treatment for 48 h.Furthermore,the Si/Al ratio in ZSM-5 seed has little effect on the topological structure and pore structure of the synthesized samples.However,the seeds with a low Si/Al ratio facilitate faster crystallization of zeolite and enhance the acidity,especially the strong acid centers,of the catalyst.The catalytic performance of the synthesized polycrystalline ZSM-5 was evaluated during dehydration of methanol and compared with a commercial reference ZSM-5r.The results exhibit that as compared with the reference catalyst,the fabricated sample has a longer catalytic lifetime(16 h vs 8 h)attributed to its hierarchical pores derived from the loosely packed primary nanoparticles.Additionally,the prepared polycrystalline catalyst also exhibits a higher aromatics selectivity(28.1%-29.8%vs 26.5%). 展开更多
关键词 ZSM-5 polycrystalline aggregate crystal seed structure guiding agent
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Differentially Private Support Vector Machines with Knowledge Aggregation
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作者 Teng Wang Yao Zhang +2 位作者 Jiangguo Liang Shuai Wang Shuanggen Liu 《Computers, Materials & Continua》 SCIE EI 2024年第3期3891-3907,共17页
With the widespread data collection and processing,privacy-preserving machine learning has become increasingly important in addressing privacy risks related to individuals.Support vector machine(SVM)is one of the most... With the widespread data collection and processing,privacy-preserving machine learning has become increasingly important in addressing privacy risks related to individuals.Support vector machine(SVM)is one of the most elementary learning models of machine learning.Privacy issues surrounding SVM classifier training have attracted increasing attention.In this paper,we investigate Differential Privacy-compliant Federated Machine Learning with Dimensionality Reduction,called FedDPDR-DPML,which greatly improves data utility while providing strong privacy guarantees.Considering in distributed learning scenarios,multiple participants usually hold unbalanced or small amounts of data.Therefore,FedDPDR-DPML enables multiple participants to collaboratively learn a global model based on weighted model averaging and knowledge aggregation and then the server distributes the global model to each participant to improve local data utility.Aiming at high-dimensional data,we adopt differential privacy in both the principal component analysis(PCA)-based dimensionality reduction phase and SVM classifiers training phase,which improves model accuracy while achieving strict differential privacy protection.Besides,we train Differential privacy(DP)-compliant SVM classifiers by adding noise to the objective function itself,thus leading to better data utility.Extensive experiments on three high-dimensional datasets demonstrate that FedDPDR-DPML can achieve high accuracy while ensuring strong privacy protection. 展开更多
关键词 Differential privacy support vector machine knowledge aggregation data utility
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A non-probabilistic reliability topology optimization method based on aggregation function and matrix multiplication considering buckling response constraints
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作者 Lei WANG Yingge LIU +2 位作者 Juxi HU Weimin CHEN Bing HAN 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第2期321-336,共16页
A non-probabilistic reliability topology optimization method is proposed based on the aggregation function and matrix multiplication.The expression of the geometric stiffness matrix is derived,the finite element linea... A non-probabilistic reliability topology optimization method is proposed based on the aggregation function and matrix multiplication.The expression of the geometric stiffness matrix is derived,the finite element linear buckling analysis is conducted,and the sensitivity solution of the linear buckling factor is achieved.For a specific problem in linear buckling topology optimization,a Heaviside projection function based on the exponential smooth growth is developed to eliminate the gray cells.The aggregation function method is used to consider the high-order eigenvalues,so as to obtain continuous sensitivity information and refined structural design.With cyclic matrix programming,a fast topology optimization method that can be used to efficiently obtain the unit assembly and sensitivity solution is conducted.To maximize the buckling load,under the constraint of the given buckling load,two types of topological optimization columns are constructed.The variable density method is used to achieve the topology optimization solution along with the moving asymptote optimization algorithm.The vertex method and the matching point method are used to carry out an uncertainty propagation analysis,and the non-probability reliability topology optimization method considering buckling responses is developed based on the transformation of non-probability reliability indices based on the characteristic distance.Finally,the differences in the structural topology optimization under different reliability degrees are illustrated by examples. 展开更多
关键词 BUCKLING topology optimization aggregation function uncertainty propagation analysis non-probabilistic reliability
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Effect of Modification Treatment on Chloride Ions Permeability and Microstructure of Recycled Brick-mixed Aggregate Concrete
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作者 何子明 申爱琴 +2 位作者 WANG Xiaobin WU Jinhua WANG Lusheng 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第3期728-737,共10页
The modification methods of pozzolan slurry combined with sodium silicate and silicon-based additive were respectively adopted to treat recycled coarse brick-mixed aggregate(RCBA)in this study.The compressive strength... The modification methods of pozzolan slurry combined with sodium silicate and silicon-based additive were respectively adopted to treat recycled coarse brick-mixed aggregate(RCBA)in this study.The compressive strength and chloride permeability resistance of recycled aggregate concrete(RAC)before and after modification treatment were tested,and the microstructure of RAC was analyzed by mercury intrusion porosimetry(MIP)and scanning electron microscopy(SEM).The results show that the physical properties of RCBA strengthened by modification treatment are improved,and the compressive strength and chloride permeability resistance of treated RAC are also significantly improved.The modification treatment optimizes the pore size distribution of RAC,which increases the number of gel pores and transition pores,and decreases the number of capillary pores and macro pores.The surface fractal dimension shows a significant correlation with chloride diffusion coefficient,indicating that the variation of chloride permeability of treated RAC is consistent with the microstructure evolution. 展开更多
关键词 recycled aggregate concrete modification treatment compressive strength chloride permeability resistance MICROSTRUCTURE
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High-efficiency Carbonation Modification Methods of Recycled Coarse Aggregates
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作者 张美香 YANG Xiaolin +3 位作者 丁亚红 SUN Bo ZHANG Xianggang LÜXiuwen 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期386-398,共13页
To solve the problem of only surface carbonation and realize high-efficiency carbonation of recycled coarse aggregate,the method of carbonated recycled coarse aggregate with nano materials pre-soaking was first put fo... To solve the problem of only surface carbonation and realize high-efficiency carbonation of recycled coarse aggregate,the method of carbonated recycled coarse aggregate with nano materials pre-soaking was first put forward.The carbonation effect of modified recycled coarse aggregate with three different carbonation methods was evaluated,and water absorption,apparent density and crush index of modified recycled coarse aggregate were measured.Combined with XRD,SEM,and MIP microscopic analysis,the high-efficiency carbonation strengthening mechanism of modified recycled coarse aggregate was revealed.The experimental results show that,compared with the non-carbonated recycled coarse aggregate,the physical and microscopic properties of carbonated recycled coarse aggregate are improved.The method of carbonation with nano-SiO_(2) pre-soaking can realize the high-efficiency carbonation of recycled coarse aggregate,for modified recycled coarse aggregate with the method,water absorption is reduced by 23.03%,porosity is reduced by 44.06%,and the average pore diameter is 21.82 nm.The high-efficiency carbonation strengthening mechanism show that the pre-socked nano-SiO_(2) is bound to the hydration product Ca(OH)_(2) of the old mortar with nano-scale C-S-H,which can improve the CO_(2) absorption rate,accelerate the carbonation reaction,generate more stable CaCO_(3) and nano-scale silica gel,and bond to the dense three-dimensional network structure to realize the bidirectional enhancement of nano-materials and pressurized carbonation.It is concluded that the method of carbonation with nano-SiO_(2) pre-soaking is a novel high-efficiency carbonation modification of recycled coarse aggregate. 展开更多
关键词 recycled coarse aggregate pressurized carbonation high-efficiency carbonation NANO-SIO2 strengthening mechanism
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Prediction Model-based Multi-objective Optimization for Mix-ratio Design of Recycled Aggregate Concrete
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作者 CHEN Tao WU Di YAO Xiaojun 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第6期1507-1517,共11页
The prediction model for mechanical properties of RAC was established through the Bayesian optimization-based Gaussian process regression(BO-GPR)method,where the input variables in BO-GPR model depend on the mix ratio... The prediction model for mechanical properties of RAC was established through the Bayesian optimization-based Gaussian process regression(BO-GPR)method,where the input variables in BO-GPR model depend on the mix ratio of concrete.Then the compressive strength prediction model,the material cost,and environmental factors were simultaneously considered as objectives,while a multi-objective gray wolf optimization algorithm was developed for finding the optimal mix ratio.A total of 730 RAC datasets were used for training and testing the predication model,while the optimal design method for mix ratio was verified through RAC experiments.The experimental results show that the predicted,testing,and expected compressive strengths are nearly consistent,illustrating the effectiveness of the proposed method. 展开更多
关键词 recycled coarse aggregate mix ratio multi-objective optimization prediction model compressive strength
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"Three-in-One" Ecological Development and Efficient Utilization Model of Aggregates
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作者 Yunkai FAN Shichang XU +2 位作者 Qiangjie HUANG Yiyuan LU Ziyi WEI 《Asian Agricultural Research》 2024年第6期13-18,共6页
Green mining and the formation of an effective and efficient development model have become key issues that aggregates enterprises around the world need to solve urgently.On the basis of analyzing the development statu... Green mining and the formation of an effective and efficient development model have become key issues that aggregates enterprises around the world need to solve urgently.On the basis of analyzing the development status of aggregates industry in Xiluodu area,the paper studied the main problems faced in the construction of green aggregates mines at present,and proposed a"three-in-one"ecological,intelligent and efficient green mine construction model for"ecological development","green logistics"and"solid waste recycling"of aggregates.The study has certain theoretical value and practical significance for the construction of green aggregates mine in Xiluodu area. 展开更多
关键词 aggregATES ECOLOGICAL development EFFICIENT UTILIZATION
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