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Influence of Human Activity Intensity on Habitat Quality in Hainan Tropical Rainforest National Park,China 被引量:1
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作者 HAN Nianlong YU Miao +2 位作者 JIA Peihong ZHANG Yucheng HU Ke 《Chinese Geographical Science》 SCIE CSCD 2024年第3期519-532,共14页
Due to long-term human activity interference,the Hainan Tropical Rainforest National Park(HTRNP)of China has experienced ecological problems such as habitat fragmentation and biodiversity loss,and with the expanding s... Due to long-term human activity interference,the Hainan Tropical Rainforest National Park(HTRNP)of China has experienced ecological problems such as habitat fragmentation and biodiversity loss,and with the expanding scope and intensity of human activity impact,the regional ecological security is facing serious challenges.A scientific assessment of the interrelationship between human activity intensity and habitat quality in the HTRNP is a prerequisite for achieving effective management of ecological disturbances caused by human activities and can also provide scientific strategies for the sustainable development of the region.Based on the land use change data in 2000,2010,and 2020,the spatial and temporal variations and the relationship between habitat quality(HQ)and human activity intensity(HAI)in the HTRNP were explored using the integrated valuation of ecosystem services and trade-offs(InVEST)model.System dynamics and land use simulation models were also combined to conduct multi-scenario simulations of their relationships.The results showed that during 2000–2020,the habitat quality of the HTRNP improved,the intensity of human activities decreased each year,and there was a negative correlation between the two.Second,the system dynamic model could be well coupled with the land use simulation model by combining socio-economic and natural factors.The simulation scenarios of the coupling model showed that the harmonious development(HD)scenario is effective in curbing the increasing trend of human activity intensity and decreasing trend of habitat quality,with a weaker trade-off between the two compared with the baseline development(BD)and investment priority oriented(IPO)scenarios.To maintain the authenticity and integrity of the HTRNP,effective measures such as ecological corridor construction,ecological restoration,and the implementation of ecological compensation policies need to be strengthened. 展开更多
关键词 human activity intensity(HAI) habitat quality(HQ) bivariate spatial autocorrelation system dynamics model integrated valuation of ecosystem services and trade-offs(InVEST)model Hainan Tropical Rainforest National Park(HTRNP)of China
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Convergence analysis for complementary-label learning with kernel ridge regression
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作者 NIE Wei-lin WANG Cheng XIE Zhong-hua 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第3期533-544,共12页
Complementary-label learning(CLL)aims at finding a classifier via samples with complementary labels.Such data is considered to contain less information than ordinary-label samples.The transition matrix between the tru... Complementary-label learning(CLL)aims at finding a classifier via samples with complementary labels.Such data is considered to contain less information than ordinary-label samples.The transition matrix between the true label and the complementary label,and some loss functions have been developed to handle this problem.In this paper,we show that CLL can be transformed into ordinary classification under some mild conditions,which indicates that the complementary labels can supply enough information in most cases.As an example,an extensive misclassification error analysis was performed for the Kernel Ridge Regression(KRR)method applied to multiple complementary-label learning(MCLL),which demonstrates its superior performance compared to existing approaches. 展开更多
关键词 multiple complementary-label learning partial label learning error analysis reproducing kernel Hilbert spaces
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Relationship between Authoritative Parenting Style and Preschool Children’s Emotion Regulation:A Moderated Mediation Model
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作者 Yan Jin Wei Chen 《International Journal of Mental Health Promotion》 2024年第3期189-198,共10页
An authoritative parenting style has been shown to promote children’s emotion regulation in European-American family studies.However,little is known about how sleep problems and the child’s sibling status in Chinese... An authoritative parenting style has been shown to promote children’s emotion regulation in European-American family studies.However,little is known about how sleep problems and the child’s sibling status in Chinese families affect this relationship.Based on family system theory,this study attempts to better understand the relationship between authoritative parenting style and emotion regulation.Mothers of preschool children in Chinese kindergartens completed questionnaires about their children’s sleep habits,their authoritative parenting styles,and children’s emotion regulation.A total of 531 children participated in this study.Results showed that authoritative parenting was positively associated with emotional regulation.Sleep problems mediated the effects of authoritative parenting style on emotion regulation.The child’s sibling status moderated the mediating effects of sleep problems in authoritative parenting and emotion regulation relationships.Specifically,the relationship between the authoritative parenting style and sleep problems was significant for only children,while birth order had no significant influence on the authoritative parenting style and sleep problems in two-child families.These findings suggest that a lowauthoritative parenting style predicts low emotion regulation through sleep problems,and this depends on the child’s sibling status,indicating that children without siblings may impair emotion regulation due to increased sleep problems. 展开更多
关键词 Sleep problem emotional regulation authoritative parenting child’s sibling status preschool children
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Carbon efficiency evaluation method for urban energy system with multiple energy complementary
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作者 Xianan Jiao Jiekang Wu +1 位作者 Yunshou Mao Mengxuan Yan 《Global Energy Interconnection》 EI CSCD 2024年第2期142-154,共13页
Urban energy systems(UESs)play a pivotal role in the consumption of clean energy and the promotion of energy cascade utilization.In the context of the construction and operation strategy of UESs with multiple compleme... Urban energy systems(UESs)play a pivotal role in the consumption of clean energy and the promotion of energy cascade utilization.In the context of the construction and operation strategy of UESs with multiple complementary energy resources,a comprehensive assessment of the energy efficiency is of paramount importance.First,a multi-dimensional evaluation system with four primary indexes of energy utilization,environmental protection,system operation,and economic efficiency and 21 secondary indexes is constructed to comprehensively portray the UES.Considering that the evaluation system may contain a large number of indexes and that there is overlapping information among them,an energy efficiency evaluation method based on data processing,dimensionality reduction,integration of combined weights,and gray correlation analysis is proposed.This method can effectively reduce the number of calculations and improve the accuracy of energy efficiency assessments.Third,a demonstration project for a UES in China is presented.The energy efficiency of each scenario is assessed using six operational scenarios.The results show that Scenario 5,in which parks operate independently and investors build shared energy-storage equipment,has the best results and is best suited for green and low-carbon development.The results of the comparative assessment methods show that the proposed method provides a good energy efficiency assessment.This study provides a reference for the optimal planning,construction,and operation of UESs with multiple energy sources. 展开更多
关键词 Urban energy systems(UESs) Multiple energy complementary system Carbon efficiency evaluation Data downscaling Subjective and objective weight Gray correlation analysis
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MOF synthesis using waste PET for applications of adsorption, catalysis and energy storage
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作者 Hongmei Li Jinming Lei +4 位作者 Liying Zhu Yanling Yao Yuanhua Li Tianhao Li Chuntian Qiu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第11期1650-1665,共16页
Polyethylene terephthalate (PET) as one of non-degradable wastes has become a huge threat to the environment and human health.Chemical Recycle of PET is a sustainable way to release 1,4-benzenedicarboxylic acid (BDC) ... Polyethylene terephthalate (PET) as one of non-degradable wastes has become a huge threat to the environment and human health.Chemical Recycle of PET is a sustainable way to release 1,4-benzenedicarboxylic acid (BDC) the monomer of PET as common used organiclinker for synthesis of functional Metal–organic-frameworks (PET-derived MOFs) such as UiO-66, MIL-101, etc. This sustainable and costeffective“Waste-to-MOFs” model is of great significant to be intensively investigated in the past years. Attributes of substantial porosity, specificsurface area, exposed metal centers, uniform structure, and flexible morphology render PET-derived MOFs are well-suited for applications inadsorption, energy storage, catalysis, among others. Herein, in the present work, we have summarized recent advances in synthesis of PETderived MOFs using ex-situ and in-situ methods for typical applications of adsorption, catalysis and energy storage. Despite those improvementsin synthesis methods and potential applications, challenges still remain in development of green and economical routes to fully utilize waste PETfor massive manufacture of valuable MOF materials and chemicals. This review provides insights into the conversion of non-degradable PETwaste to value-added MOF materials, and further suggests promising perspectives to develop the sustainable “Waste-to-MOFs” model inaddressing environmental pollution and energy crises. 展开更多
关键词 Plastic waste Polyethylene terephthalate Chemical recycle 1 4-benzenedicarboxylic acid Metal organic frameworks
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Genome-Wide Analysis of the F3′5′H Gene Family in Blueberry(Vaccinium corymbosum L.)Provides Insights into the Regulation of Anthocyanin Biosynthesis
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作者 Xiaolan Guo Jinbin Hu +2 位作者 Shimei Yang Delu Wang Jianbing Wang 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第9期2683-2697,共15页
The F3′5′H gene family plays an important role in regulating anthocyanin biosynthesis,abiotic stress,and hormone signaling.In this study,14 F3′5′H genes were identified from the blueberry genome.The chromosomal di... The F3′5′H gene family plays an important role in regulating anthocyanin biosynthesis,abiotic stress,and hormone signaling.In this study,14 F3′5′H genes were identified from the blueberry genome.The chromosomal distribution,physicochemical properties,F3′5′H domain,conserved motifs,cis-acting elements,and intron/exon compositions were analyzed.The functional prediction analysis of these VcF3′5′Hs indicated that their biological functions included light response and other secondary metabolites.The results of qRT-PCR showed that VcF3′5′Hs(especially VcF3′5′H4)were highly expressed at the ripening stage.Subcellular localization revealed that VcF3′5′H4 may be located in the endoplasmic reticulum.Co-expression analysis showed that the VcF3′5′H gene family was related to anthocyanin.This research provides an overview of the blueberry F3′5′H family and helps verify the role of these genes in regulating anthocyanin biosynthesis. 展开更多
关键词 BLUEBERRY F3′5′H ANTHOCYANIN gene expression CO-EXPRESSION
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The Effects of Water and Fertilizer Coupling on Plant and Soil Nitrogen Characteristics and Fruit Growth of Rabbiteye Blueberry Plants in a Semi-Arid Region in China
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作者 Xiaolan Guo Di Zhao +3 位作者 Jinbin Hu Delu Wang Jianbin Wang Muhammad Shakeel 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第1期209-223,共15页
To evaluate the effects of nitrogen(N)and irrigation coupling on the soil N distribution,plant N utilization,and fruit yield of rabbiteye blueberries(Vaccinium virgatum),a field experiment was designed using two facto... To evaluate the effects of nitrogen(N)and irrigation coupling on the soil N distribution,plant N utilization,and fruit yield of rabbiteye blueberries(Vaccinium virgatum),a field experiment was designed using two factors(water and fertilizer application)with four levels of irrigation and three levels of fertilization,and a control.Under the different water and fertilizer combinations,N primarily accumulated in the leaves.Irrigation and N application within appropriate ranges(pure N≤29 g/plant and irrigation volume≤2.5 L/plant)significantly improved the blueberry fruit yield.Increases in water and N within these ranges promoted the effective accumulation of N in various organs and the absorption and utilization of N in the plants,which ultimately promoted blueberry yield.With increased N application rate,the nitrate N content of the 0–20 cm and 20–50 cm soil layers increased.With increased irrigation volume,the nitrate N content of the 0–20 cm soil layer decreased,while the nitrate content in the 20–50 cm soil layer increased.Low N and moderate water treatments resulted in high fruit yields and reduced nitrate N retention in the soil.Under these conditions,the economic input-output ratio was high and the soil N accumulation was low,and thus the economic and ecological benefits were maximized. 展开更多
关键词 Vaccinium virgatum soil nitrogen distribution plant nitrogen utilization fruit yield
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Pedestrian and Vehicle Detection Based on Pruning YOLOv4 with Cloud-Edge Collaboration
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作者 Huabin Wang Ruichao Mo +3 位作者 Yuping Chen Weiwei Lin Minxian Xu Bo Liu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第11期2025-2047,共23页
Nowadays,the rapid development of edge computing has driven an increasing number of deep learning applications deployed at the edge of the network,such as pedestrian and vehicle detection,to provide efficient intellig... Nowadays,the rapid development of edge computing has driven an increasing number of deep learning applications deployed at the edge of the network,such as pedestrian and vehicle detection,to provide efficient intelligent services to mobile users.However,as the accuracy requirements continue to increase,the components of deep learning models for pedestrian and vehicle detection,such as YOLOv4,become more sophisticated and the computing resources required for model training are increasing dramatically,which in turn leads to significant challenges in achieving effective deployment on resource-constrained edge devices while ensuring the high accuracy performance.For addressing this challenge,a cloud-edge collaboration-based pedestrian and vehicle detection framework is proposed in this paper,which enables sufficient training of models by utilizing the abundant computing resources in the cloud,and then deploying the well-trained models on edge devices,thus reducing the computing resource requirements for model training on edge devices.Furthermore,to reduce the size of the model deployed on edge devices,an automatic pruning method combines the convolution layer and BN layer is proposed to compress the pedestrian and vehicle detection model size.Experimental results show that the framework proposed in this paper is able to deploy the pruned model on a real edge device,Jetson TX2,with 6.72 times higher FPS.Meanwhile,the channel pruning reduces the volume and the number of parameters to 96.77%for the model,and the computing amount is reduced to 81.37%. 展开更多
关键词 Pedestrian and vehicle detection YOLOv4 channel pruning cloud-edge collaboration
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Non-solvating fluorosulfonyl carboxylate enables temperature-tolerant lithium metal batteries
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作者 Xianshu Wang Junru Wu +8 位作者 Yun Zhao Bin Li Naser Tavajohi Qi Liu Jianguo Duan Ding Wang Peng Dong Yingjie Zhang Baohua Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第7期287-295,I0007,共10页
Advanced electrolyte engineering is an important strategy for developing high-efficacy lithium(Li)metal batteries(LMBs).Unfortunately,the current electrolytes limit the scope for creating batteries that perform well o... Advanced electrolyte engineering is an important strategy for developing high-efficacy lithium(Li)metal batteries(LMBs).Unfortunately,the current electrolytes limit the scope for creating batteries that perform well over temperature ranges.Here,we present a new electrolyte design that uses fluorosulfonyl carboxylate as a non-solvating solvent to form difluoroxalate borate(DFOB-)anion-rich solvation sheath,to realize high-performance working of temperature-tolerant LMBs.With this optimized electrolyte,favorable SEI and CEI chemistries on Li metal anode and nickel-rich cathode are achieved,respectively,leading to fast Li^(+)transfer kinetics,dendrite-free Li deposition and suppressed electrolyte deterioration.Therefore,Li||LiNi_(0.80)Co_(0.15)Al_(0.05)O_(2)batteries with a thin Li foil(50μm)show a long-term cycling lifespan over 400 cycles at 1C and a superior capacity retention of 90%after 200 cycles at 0.5C under 25℃.Moreover,this electrolyte extends the operating temperature from-10 to 30℃and significantly improve the capacity retention and Coulombic efficiency of batteries are improved at high temperature(60℃).Fluorosulfonyl carboxylates thus have considerable potential for use in high-performance and allweather LMBs,which broadens the new exploring of electrolyte design. 展开更多
关键词 Lithium metal batteries Methyl fluorosulfonyldifluoroacetate Non-solvating Anion-rich solvation Temperature tolerance
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The Evolution of Landscape Layout Concept of Lingnan Taoist Zuting Temples in the Qing Dynasty
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作者 Chaohui Lin 《Natural Resources》 2023年第8期121-133,共13页
The replacement of Lingnan Taoist Zuting Temples from Lingbao Sect to Quanzhen Sect in the Qing Dynasty has led to the change of the layout of Taoist temples on Luofu Mountain. Through literature review, field researc... The replacement of Lingnan Taoist Zuting Temples from Lingbao Sect to Quanzhen Sect in the Qing Dynasty has led to the change of the layout of Taoist temples on Luofu Mountain. Through literature review, field research, image comparison and other research methods, the paper explores how the layout of the Taoist temples on Luofu Mountain evolved from the Four Taoist Temples in the Gehong period to the Five Taoist Temples in the Qing Dynasty under the influence of different Taoist ideologies, aiming to explore the cultural implications of the evolution of the layout of Lingnan Taoism Zuting Temple in the Qing Dynasty. 展开更多
关键词 Luofu Mountain Taoist Temple TAOISM Layout Concept
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Influence of explosion parameters on wavelet packet frequency band energy distribution of blast vibration 被引量:13
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作者 中国生 敖丽萍 赵奎 《Journal of Central South University》 SCIE EI CAS 2012年第9期2674-2680,共7页
Blast vibration analysis is one of the important foundations for studying the control technology of blast vibration damage. According to blast vibration live data that have been collected and the characteristics of sh... Blast vibration analysis is one of the important foundations for studying the control technology of blast vibration damage. According to blast vibration live data that have been collected and the characteristics of short-time non-stationary random signals, the wavelet packet energy spectrum analysis for blast vibration signal has made by wavelet packet analysis technology and the signals were measured under different explosion parameters (the maximal section dose, the distance of blast source to measuring point and the section number of millisecond detonator). The results show that more than 95% frequency band energy of the signals sl-s8 concentrates at 0-200 Hz and the main vibration frequency bands of the signals sl-s8 are 70.313-125, 46.875-93.75, 15.625-93.75, 0-62.5, 42.969-125, 15.625-82.031, 7.813-62.5 and 0-62.5 Hz. Energy distributions for different frequency bands of blast vibration signal are obtained and the characteristics of energy distributions for blast vibration signal measured under different explosion parameters are analyzed. From blast vibration signal energy, the decreasing law of blast seismic waves measured under different explosion parameters was studied and the wavelet packet analysis is an effective means for studying seismic effect induced by blast. 展开更多
关键词 blast vibration wavelet packet analysis explosion parameter energy distribution
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Effects of Chilling Stress on Photosynthetic Rate and Chlorophyll Fluorescence Parameter in Seedlings of Two Rice Cultivars Differing in Cold Tolerance 被引量:5
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作者 WANG Guo-li Guo Zhen-fei 《Rice science》 SCIE 2005年第3期187-191,共5页
A cold-tolerant cultivar, Xiangnuo 1, and a cold-sensitive cultivar, IR50, were used to study the influence of chilling on photosynthetic rate and chlorophyll fluorescence parameters in rice seedlings. The photosynthe... A cold-tolerant cultivar, Xiangnuo 1, and a cold-sensitive cultivar, IR50, were used to study the influence of chilling on photosynthetic rate and chlorophyll fluorescence parameters in rice seedlings. The photosynthetic rates declined dramatically during chilling, and decreased by 48.7% and 67.5% in Xiangnuo 1 and IR50 seedlings, respectively, after being subjected to chilling treatment for two days. Chlorophyll fluorescence measurements showed that relatively higher qp and qNP in Xiangnuo 1 were maintained to dissipate the redundant excitation energy and protect the reaction centers from chill injury; accordingly, redundant excitation energy accumulated less in the reaction centers, and antenna systems were less injured by chilling in Xiangnuo 1. On the contrary, in IR50, qp and qNP declined rapidly while Eg increased, as the chilling persisted. This result indicated that the reaction centers and antenna systems in IR50 were damaged severely by chilling, which led to the lower photosynthetic rate. 展开更多
关键词 CHILLING RICE photosynthetic rate chlorophyll fluorescence analysis
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Screening and characterization of a novel ruminal cellulase gene(Umcel-1) from a metagenomic library of gayal(Bos frontalis) 被引量:3
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作者 LI Bi-feng ZHU Ya-xin +8 位作者 GU Zhao-bing CHEN Yuan LENG Jing GOU Xiao FENG Li LI Qing XI Dong-mei MAO Hua-ming YANG Shu-Li 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第4期855-861,共7页
Gayal is a rare semi-wild bovine species found in the Indo-China. They can graze grasses, including bamboo leaves, as well as reeds and other plant species, and grow to higher mature live weights than Yunnan Yellow ca... Gayal is a rare semi-wild bovine species found in the Indo-China. They can graze grasses, including bamboo leaves, as well as reeds and other plant species, and grow to higher mature live weights than Yunnan Yellow cattle maintained in similar harsh environments. The aim of this study was to identify specific cellulase in the gayal rumen. A metagenomic fosmid library was constructed using genomic DNA isolated from the ruminal contents of four adult gayals. This library contained 38400 clones with an average insert size of 35.5 kb. The Umcel-1 gene was isolated from this library. Investigation of the cellulase activity of 24 random clones led to the identification of the Umcel-1 gene, which exhibited the most potent cellulase activity. Sequencing the Umcel-1 gene revealed that it contained an open reading frame of 942 base pairs that encoded a product of 313 amino acids. The putative gene Umcel-1 product belonged to the glycosyl hydrolase family 5 and showed the highest homology to the cellulase (GenBank accession no. YP_004310852.1 ) from Clostridium lentocellum DSM 5427, with 44% identity and 62% similarity. The Umcel-1 gene was heterologously expressed in Escherichia coil BL21, and recombinant Umcel-1 was purified. The activity of purified recombinant Umcel-1 was assessed, and the results revealed that it hydrolyzed carboxymethyl cellulose with optimal activity at pH 5.5 and 45~C. To our knowledge, this study provides the first evidence for a cellulase produced by bacteria in gayal rumen. 展开更多
关键词 GAYAL ruminal microorganism fosmid library Umcel-I gene gene expression cellulase activity
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β-Cyclodextrin Promoted Oxidation of Cinnamaldehyde to Natural Benzaldehyde in Water 被引量:2
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作者 陈鸿雁 纪红兵 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第6期972-977,共6页
A facile and efficient procedure has been developed systematically for the oxidative cleavage of cinna-maldehyde to benzaldehyde by sodium hypochlorite with water as the only solvent in the presence of β-cyclodextrin... A facile and efficient procedure has been developed systematically for the oxidative cleavage of cinna-maldehyde to benzaldehyde by sodium hypochlorite with water as the only solvent in the presence of β-cyclodextrin (abbreviated as β-CD). Different factors influencing cinnamaldehyde oxidation e.g. reaction temperature, the amount of catalyst and oxidant, have been investigated. The yield of benzaldehyde reaches 76% under the optimum conditions (333 K, 4 h, molar ratio of cinnamaldehyde to β-CD is 1:1). Furthermore, a feasible reaction mecha-nism including the formation of benzaldehyde and the two main byproducts (phenylacetaldehyde and epoxide of cinnamaldehyde) has been proposed. 展开更多
关键词 oxidative cleavage -CYCLODEXTRIN CINNAMALDEHYDE natural benzaldehyde sodium hypochlorite
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A Decentralized Prediction Market Platform Based on Blockchain and Masternode Technologies 被引量:1
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作者 Zhen Wang 《China Communications》 SCIE CSCD 2020年第9期25-33,共9页
Prediction market can help to trade the outcome of events,which is very useful for risk hedging,especially when people are making business ventures.However,the traditional prediction market is centralized,which means ... Prediction market can help to trade the outcome of events,which is very useful for risk hedging,especially when people are making business ventures.However,the traditional prediction market is centralized,which means the platform is completely controlled by just one person or team.This centralization has bad influence on the platform to obtaining trust from massive users.So it is important for the prediction market industry to decentralize the traditional platform into a decentralized one,and get its control from few person and give it back to a lot of people in the prediction market community.Blockchain is a very promising technology to make it true as it is a popular decentralizing technology.However,existing blockchain technologies like Bitcoin or Ethernum bring about new problems like high energy consumption,expensive fee,and very low system capacity,which is not suitable for the current prediction market.To solve these problems,we propose to combine masternode technology together with blockchain to serve as a decentralized node,and each masternode is deployed and running on an edge server in mobile edge network.The network of masternodes serves together as the decentralized prediction market platform.As we know,it is not easy to run a masternode.So the number of masternodes is much less than the number of complete nodes of the blockchain.As a result,it is easier to reach the consensus among these masternodes.Theoretical analysis and experimental results show that our proposed method is useful. 展开更多
关键词 prediction market DECENTRALIZATION blockchain masternode mobile edged computing
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Finite-time stability and stabilization of Markovian switching stochastic systems with impulsive effects 被引量:1
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作者 Ying Yang Junmin Li Guopei Chen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第2期254-260,共7页
Many practical systems in physics, biology, engineer- ing and information science exhibit impulsive dynamical behaviors due to abrupt changes at certain instants during the dynami- cal processes. The problems of finit... Many practical systems in physics, biology, engineer- ing and information science exhibit impulsive dynamical behaviors due to abrupt changes at certain instants during the dynami- cal processes. The problems of finite-time stab!lity analysis are investigated for a class of Markovian switching stochastic sys- tems, in which exist impulses at the switching instants. Multiple Lyapunov techniques are used to derive sufficient conditions for finite-time stochastic stability of the overall system. Furthermore, a state feedback controller, which stabilizes the closed loop sys- tems in the finite-time sense, is then addressed. Moreover, the controller appears not only in the shift part but also in the diffu- sion part of the underlying stochastic subsystem. The results are reduced to feasibility problems involving linear matrix inequalities (LMIs). A numerical example is presented to illustrate the proposed methodology. 展开更多
关键词 finite-time stability impulsive systems Markovian switching Brownian motion linear matrix inequalities (LMIs) sta- bilization.
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Purification and characterization of acetylcholinesterase from brain tissues of Oreochromis aurea and its application in environmental pesticide monitoring 被引量:1
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作者 YunHua Ding XiaoMin Wu JunBin Fang 《Research in Cold and Arid Regions》 2011年第4期339-343,共5页
Acetylcholinesterase (ACHE) plays an important role in enzyme-based detection of pesticides in the environment. In this paper, ACHE from the Triton X-100 extract of brain tissues of Oreochromis aurea was purified by... Acetylcholinesterase (ACHE) plays an important role in enzyme-based detection of pesticides in the environment. In this paper, ACHE from the Triton X-100 extract of brain tissues of Oreochromis aurea was purified by (NH4)2SO4 fractional precipitation, Sephadex G-100 gel filtration, and DEAE-cellulose ion exchange chromatography. Certain biochemical characterizations of the purified enzyme and inhibition of pesticides on the enzyme were also studied. The specific activity of this purified enzyme was 20.628 U/mg protein, fold of purification was 139, and recovery was 22.1%. The optimal temperature of this enzyme was between 35-40 ℃, and optimal pH was between 7.5-8.0. The Michaelis constant (Kin) for acetylthiocholine iodide was 0.183 mmol/L. The enzyme activity was inhibited by excess substrate, and optimal substrate concentration was 6 mmol/L. Four pesticides (dichlorvos, phoxim, triazophos, and methomyl) exhibited strong inhibitions on this enzyme with IC50 less than 5 μg/mL. This study suggests that Oreochromis aurea (tilapia) could be a good enzyme source for pesticide monitoring in water environments. 展开更多
关键词 Oreochromis aurea ACETYLCHOLINESTERASE PURIFICATION gel filtration ion-exchange chromatography pesticide sensitivity
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Vibration Effect and Damage Evolution Characteristics of Tunnel Surrounding Rock Under Cyclic Blasting Loading 被引量:1
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作者 Guosheng Zhong Yongzhong Lou Yuhua Fu 《Journal of Beijing Institute of Technology》 EI CAS 2017年第3期324-333,共10页
Model test studies based on the similarity theory were conducted to investigate vibration effect and damage evolution characteristics of tunnel surrounding rock under push-type cyclic blasting excavation.The model was... Model test studies based on the similarity theory were conducted to investigate vibration effect and damage evolution characteristics of tunnel surrounding rock under push-type cyclic blasting excavation.The model was constructed with a ratio of 1∶15.By simulating the tunnel excavation of push-type cyclic blasting,the influence of the blasting parameter change on vibration effect was explored.The damage degree of tunnel surrounding rock was evaluated by the change of the acoustic wave velocity at the same measuring point after blasting.The relationship between the damage evolution of surrounding rock and blasting times was established.The research results show that:(1)In the same geological environment,the number of delay initiation is larger,the main vibration frequency of blasting seismic wave is higher,and the attenuation of high frequency signal in the rock and soil is faster.The influence of number of delay initiation on blasting vibration effect cannot be ignored;(2)Under push-type cyclic blasting excavation,there were great differences in the decreasing rates of acoustic wave velocity of the measuring points which have the same distance to the blasting region at the same depth,and the blasting damage ranges of surrounding rock were typically anisotropic at both depth and breadth;(3)When blasting parameters were basically kept as the same,the growth trend of the cumulative acoustic wave velocity decreasing rate at the measuring point was nonlinear under different cycle blasting excavations;(4)There were nonlinear evolution characteristics between the blasting cumulative damage(D)of surrounding rock and blasting times(n)under push-type cyclic blasting loading,and different measuring points had corresponding blasting cumulative damage propagation models,respectively.The closer the measuring point was away from the explosion source,the faster the cumulative damage extension.Blasting cumulative damage effect of surrounding rock had typically nonlinear evolution properties and anisotropic characteristics. 展开更多
关键词 cyclic blasting loading tunnel excavation vibration effect surrounding rock damage
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ANOMALOUS EFFECT OF PRESSURE ON THE CURIE TEMPERATURE IN MECHANICALLY ALLOYED Fe-Ni INVAR 被引量:1
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作者 X.H. Wei F. Ono 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2007年第3期205-209,共5页
Measurements of magnetic susceptibility in mechanically alloyed Fe-Ni Invar alloys were taken under pressures up to 7.5GPa. The rate of decrease in the Curie temperature for 700℃ annealed specimen was larger than tha... Measurements of magnetic susceptibility in mechanically alloyed Fe-Ni Invar alloys were taken under pressures up to 7.5GPa. The rate of decrease in the Curie temperature for 700℃ annealed specimen was larger than that annealed at 1000℃. This result can be explained by considering the fact that the width of the concentration fluctuation becomes larger in the specimen annealed at lower temperature. 展开更多
关键词 invar alloy Fe-Ni mechanical alloying Curie temperature
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Iron(Fe,Ni,Co)-based transition metal compounds for lithium-sulfur batteries:Mechanism,progress and prospects 被引量:2
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作者 Junhao Li Zhangshi Xiong +6 位作者 Yujie Wu Hao Li Xinyan Liu Hongjie Peng Yuying Zheng Qiang Zhang Quanbing Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第10期513-532,I0013,共21页
Lithium-sulfur batteries(LSBs)have a high theoretical capacity,which is considered as one of the most promising high-energy-density secondary batteries due to the double electrons reaction of sulfur.However,the shuttl... Lithium-sulfur batteries(LSBs)have a high theoretical capacity,which is considered as one of the most promising high-energy-density secondary batteries due to the double electrons reaction of sulfur.However,the shuttle effects of lithium polysulfides(Li PSs)and sluggish redox kinetics lead to their materials capacity loss and cycle stability deterioration,which restrains LSBs commercialization.Metallic compounds as additions can improve the electrochemical performance of the Li-S system,through the trap of Li PSs and accelerate the conversion of the soluble Li PSs.Among of them,the iron group elements(Fe,Ni,Co)-based compounds are the promising materials for the LSBs,due to their unique outer electronic structure and its tunable properties,low cost,abundant in the earth,environmental benignity,controllable and scalable prepared,and so on.In this review,we have made a summary for iron-based compounds to capture Li PSs according to lithium bond,sulfur bond and magnetic force.The type of iron-based compound including oxides,sulfides,nitrides,phosphides,carbides,and so on,and we have investigated the electrocatalytic mechanism of these materials.Besides,some improvement strategies are proposed,such as the engineering of the special micro/nanostructure,defect concentrations,band structures,and heterostructures.We hope to shed an in-depth light on the rationally design and fabrication of robust,commercial and stable materials for high-performance LSBs. 展开更多
关键词 Li-S batteries Iron-based compounds Shuttle effect Capture LiPSs ELECTROCATALYSIS Rational design
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