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人工神经网络与遗传算法预测液体晃荡参数的比较
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作者 Hassan Saghi Mohammad Reza Sarani Nezhad +1 位作者 Reza Saghi Sepehr Partovi Sahneh 《哈尔滨工程大学学报(英文版)》 CSCD 2024年第2期292-301,共10页
This paper develops a numerical code for modelling liquid sloshing.The coupled boundary element-finite element method was used to solve the Laplace equation for inviscid fluid and nonlinear free surface boundary condi... This paper develops a numerical code for modelling liquid sloshing.The coupled boundary element-finite element method was used to solve the Laplace equation for inviscid fluid and nonlinear free surface boundary conditions.Using Nakayama and Washizu’s results,the code performance was validated.Using the developed numerical mode,we proposed artificial neural network(ANN)and genetic algorithm(GA)methods for evaluating sloshing loads and comparing them.To compare the efficiency of the suggested methods,the maximum free surface displacement and the maximum horizontal force exerted on a rectangular tank’s perimeter are examined.It can be seen from the results that both ANNs and GAs can accurately predict η_(max) and F_(max). 展开更多
关键词 Sloshing loads Fluid structure interactions Potential flow analysis Artificial neural network Genetic algorithm
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Comparative Genomic Analysis of Enterovirus 71 Revealed Six New Potential Neurovirulence-associated Sites 被引量:6
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作者 JIA Qing Jun CHEN Xin Yu +4 位作者 LI De Zhou XU Juan Juan XU Zhi Gang DUAN Zhi Liang WEN Jin Sheng 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2016年第10期767-772,共6页
In the present study,the complete genomes of four common(4/EV71/Wenzhou/CHN/2014,15/EV71/Wenzhou/CHN/2014,116/EV71/Wenzhou/CHN/2014,and 120/EV71/Wenzhou/CHN/2014)and two virulent(11/EV71/Wenzhou/CHN/2014and 109/EV7... In the present study,the complete genomes of four common(4/EV71/Wenzhou/CHN/2014,15/EV71/Wenzhou/CHN/2014,116/EV71/Wenzhou/CHN/2014,and 120/EV71/Wenzhou/CHN/2014)and two virulent(11/EV71/Wenzhou/CHN/2014and 109/EV71/Wenzhou/CHN/2014)enterovirus 71(EV71)isolates were sequenced and described.They are 7405 bp in length and belong to EV71 sub-genotype C4 (C4a cluster). 展开更多
关键词 CHN UTR EV Comparative Genomic analysis of Enterovirus 71 Revealed Six New Potential Neurovirulence-associated Sites
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Analysis on Uranium Mineralization Potential of Late Yanshanian Granites in Sichuan of Sanjiang Area 被引量:1
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作者 YIN Minghui XU Zhengqi +1 位作者 Zhou Ting SUN Kang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期103-104,共2页
The Sanjiang area is an important granite distribution area in China,except for South China,in which granites is complex and complete.Based on fully collecting date about it,this paper explores the significance of ura... The Sanjiang area is an important granite distribution area in China,except for South China,in which granites is complex and complete.Based on fully collecting date about it,this paper explores the significance of uranium 展开更多
关键词 area analysis on Uranium Mineralization Potential of Late Yanshanian Granites in Sichuan of Sanjiang Area
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Potential Analysis of Inefficient Garden Land and Residual Forest Land Remediation in Comprehensive Land Remediation of the Whole Region—A Case Study of Zhemu Town, Guilin City, China
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作者 Mingyuan Liu Xiangwen Cai +2 位作者 Yuening Song Yan Zhao Zehao Liu 《Journal of Geoscience and Environment Protection》 2021年第10期79-90,共12页
The remediation of inefficient garden land and defective forest land is one of th</span><span style="font-family:Verdana;">e important sources and types of supplementary cultivated land in th<... The remediation of inefficient garden land and defective forest land is one of th</span><span style="font-family:Verdana;">e important sources and types of supplementary cultivated land in th</span><span style="font-family:Verdana;">e comprehensive land remediation of the whole region. The remediation and development of inefficient garden land and defective forest land will effectively alleviate the multiple pressures faced by cultivated land at present. Taking Zhemu Town, Guilin City, China as an example, on that basis of the data of the third national land survey, using analytic hierarchy process, this paper selects six evaluation factors, including water source, traffic, slope, field concentration, farmland infrastructure and villagers’ will, to study the remediation potential of inefficient garden land and defective forest land in Zhemu Town, and delimits four potential divisions, in order to provide </span></span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">basis for the arrangement of land remediation projects in Zhemu Town. The results show that the northern, central and western regions of Zhemu Town have great remediation potential. 展开更多
关键词 Analytic Hierarchy Process Inefficient Garden Defective Forest Land Potential analysis Comprehensive Improvement of Land in the Whole Region
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Periodic energy decomposition analysis for electronic transport studies as a tool for atomic scale device manufacturing
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作者 Paven Thomas Mathew Fengzhou Fang 《International Journal of Extreme Manufacturing》 2020年第1期164-172,共9页
Atomic scale manufacturing is a necessity of the future to develop atomic scale devices with high precision.A different perspective of the quantum realm,which includes the tunnelling effect,leakage current at the atom... Atomic scale manufacturing is a necessity of the future to develop atomic scale devices with high precision.A different perspective of the quantum realm,which includes the tunnelling effect,leakage current at the atomic-scale,Coulomb blockade and Kondo effect,is inevitable for the fabrication and hence,the mass production of these devices.For these atomic-scale device development,molecular level devices must be fabricated.Proper theoretical studies could be an aid towards the experimental realities.Electronic transport studies are the basis to realise and interpret the problems happening at this minute scale.Keeping these in mind,we present a periodic energy decomposition analysis(pEDA)of two potential candidates for moletronics:phthalocyanines and porphyrins,by placing them over gold substrate cleaved at the(111)plane to study the adsorption and interaction at the interface and then,to study their application as a channel between two electrodes,thereby,providing a link between pEDA and electronic transport studies.pEDA provides information regarding the bond strength and the contribution of electrostatic energy,Pauli’s energy,orbital energy and the orbital interactions.Combining this analysis with electronic transport studies can provide novel directions for atomic/close-toatomic-scale manufacturing(ACSM).Literature survey shows that this is the first work which establishes a link between pEDA and electronic transport studies and a detailed pEDA study on the above stated molecules.The results show that among the molecules studied,porphyrins are more adsorbable over gold substrate and conducting across a molecular junction than phthalocyanines,even though both molecules show a similarity in adsorption and conduction when a terminal thiol linker is attached.A further observation establishes the importance of attractive terms,which includes interaction,orbital and electrostatic energies,in correlating the pEDA study with the transport properties.By progressing this research,further developments could be possible in atomic-scale manufacturing in the future. 展开更多
关键词 PHTHALOCYANINE PORPHYRIN potential energy decomposition analysis potential energy surface scan moletronics ACSM Manufacturing III
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Analysis on Prospecting Potential of Tungsten Polymetallic Ore in Haergeng of Gonghe County, Qinghai Province
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作者 LI Peng ZHOU Ting YIN Minghui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期179-180,共2页
The discovery of Gonghe County Haergeng tungsten polymetallic deposit is one of the most important tungsten deposits discovered in Qinghai Province in recent years.It has important theoretical and practicalsignificanc... The discovery of Gonghe County Haergeng tungsten polymetallic deposit is one of the most important tungsten deposits discovered in Qinghai Province in recent years.It has important theoretical and practicalsignificance.1 Regional geological background The research area lies in the northwest edge of 展开更多
关键词 area Qinghai Province analysis on Prospecting Potential of Tungsten Polymetallic Ore in Haergeng of Gonghe County
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HEFEI BASIN IN EARLY CRETACEOUS-CHARACTERIZATION AND ANALYSIS OF PETROLEUM POTENTIAL
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作者 YIWanxia ZHAOZongju +2 位作者 LIXuetian SHENJinlong ZHOUJingao 《Geotectonica et Metallogenia》 2003年第1期130-144,共15页
Comprehensive analyses were made based on seismic prospecting data, electrical prospecting data and basin simulation data as well as regional geological data and thorough discussions were conducted about the complicat... Comprehensive analyses were made based on seismic prospecting data, electrical prospecting data and basin simulation data as well as regional geological data and thorough discussions were conducted about the complicated structures, features and evolution of Hefei Basin in Early Cretaceous in this study, and it was derived that that Hefei Basin was a composite basin formed during the transformation of the stress field from compressive toward tensile in Early Cretaceous. In other words, this basin was a foreland basin of gliding-thrust type, which is mainly controlled by the Dabie orogenic belt in the south side in the early to middle period of Early Cretaceous, while being a strike-slip basin of pull-apart type, which is mainly controlled by the activity of Tanlu fracture in the east side in the middle to late period of Early Cretaceous. Moreover, the potential Lower Cretaceous oil and gas system in the pull-apart basin and the vista for its prospecting were explored in this study. Tectonism of the Tanlu fracture was further discussed based on the results of characterization of the basin, and it was pointed out that this is beneficial and instructive to the oil and gas prospecting in Hefei Basin 展开更多
关键词 Early Cretaceous Hefei Basin Dabie orogenic belt Tanlu fault analysis of oil and gas potential Anhui.
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On the road towards the global analysis of human synapses
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作者 G.Aleph Prieto Carl W.Cotman 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第10期1586-1589,共4页
Synapses are essential units for the flow of information in the brain.Over the last 70 years,synapses have been widely studied in multiple animal models including worms,fruit flies,and rodents.In comparison,the study ... Synapses are essential units for the flow of information in the brain.Over the last 70 years,synapses have been widely studied in multiple animal models including worms,fruit flies,and rodents.In comparison,the study of human synapses has evolved significantly slower,mainly because of technical limitations.However,three novel methods allowing the analysis of molecular,morphological,and functional properties of human synapses may expand our knowledge of the human brain.Here,we briefly describe these methods,and evaluate how the information provided by each unique approach may contribute to the functional and anatomical analysis of the synaptic component of human brain circuitries.In particular,using tissue from cryopreserved human brains,synaptic plasticity can be studied in isolated synaptosomes by fluorescence analysis of single-synapse long-term potentiation(FASS-LTP),and subpopulations of synapses can be thoroughly assessed in the ribbons of brain tissue by array tomography(AT).Currently,it is also possible to quantify synaptic density in the living human brain by positron emission tomography(PET),using a novel synaptic radio-ligand.Overall,data provided by FASS-LTP,AT,and PET may significantly contribute to the global understanding of synaptic structure and function in both healthy and diseased human brains,thus directly impacting translational research. 展开更多
关键词 fluorescence analysis of single-synapse long-term potentiation array tomography positron emission tomography synaptosomes flow cytometry microscopy [11C]UCB-J[(R)-1-((3-(11C-methyl-11C)pyridin-4-yl)methyl)-4-(3 4 5-trifluorophenyl)pyrrolidin-2-one]
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Geotourism as a 16-Geosite Empowerment Strategy—For Tourism Sustainability in Toba Caldera Geopark
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作者 Said Muzambiq Zaid Perdana Nst +1 位作者 Gustanto   Raja Sabrina 《Journal of Geographic Information System》 2023年第2期294-307,共14页
The study on empowerment strategies for tourism sustainability was carried out in 16 geosites located in seven regencies. These include Karo, Dairi, Simalungun, Samosir, Toba Samosir, North Tapanuli, and Humbang Hasun... The study on empowerment strategies for tourism sustainability was carried out in 16 geosites located in seven regencies. These include Karo, Dairi, Simalungun, Samosir, Toba Samosir, North Tapanuli, and Humbang Hasundutan, in Toba Caldera Region (TCA), North Sumatra Province. The empowerment strategies will enhance local and national tourism development policy directives, boost development geared towards community tourism interests, and achieve GGN directives according to the concepts outlined by UNESCO. This geotourism development has been formulated through a synthesis of various investigations including the analyses of government references, potential tourist attractions, and SWOT. Furthermore, the SWOT analysis showed that a travel plan combining the elements of cultural heritage and geosites is an alternative empowerment for sustainable regional development through geotourism, using Pusuk Bukit as a pilot area. Geosites have been mapped as the basis for Toba Caldera’s development. 展开更多
关键词 analysis of Potential Tourist Attractions SWOT analysis GEOTOURISM Policy Studies Caldera Toba
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Characterization of an ionic liquid electrospray thruster with a porous ceramic emitter 被引量:7
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作者 Chong CHEN Maolin CHEN Haohao ZHOU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2020年第9期66-74,共9页
An ionic liquid(IL)electrospray thruster was developed for application in micro-nano satellites or gravitational wave detectors.The thruster employed a porous ceramic emitter with seven emitter strips located on its e... An ionic liquid(IL)electrospray thruster was developed for application in micro-nano satellites or gravitational wave detectors.The thruster employed a porous ceramic emitter with seven emitter strips located on its emission surface.Without any liquid-supply device,IL was delivered through porous media to emitter strips via capillary effect.Multiple emission sites then formed at the tip of each strip.A charged beam of up to 350μA(with a current density of 540μA cm^(-2))was stably produced in the negative mode.However,in the positive mode,a corona was observed which could prevent the thruster from emitting larger current.A time-of-flight mass spectrometer with significantly improved signal-to-noise ratio was built,which was used to obtain the mass distribution of the beam of the thruster.A retarding potential analysis was also performed.The test results showed that the thruster worked in the pure-ion regime,and delivered a maximum thrust of 67.1μN with specific impulses of 3952 s and 3117 s in the positive and negative modes,respectively. 展开更多
关键词 electrospray thruster time-of-flight(TOF) retarding potential analysis(RPA)
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Optimization of endcap trap for single-ion manipulation
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作者 Yuan Qian Chang-Da-Ren Fang +2 位作者 Yao Huang Hua Guan and Ke-Lin Gao 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第6期280-284,共5页
Potential distribution is an important characteristic for evaluating the performance of an ion trap. Here, we analyze and optimize the potential distribution of an endcap ion trap for single-ion trapping.We obtain an ... Potential distribution is an important characteristic for evaluating the performance of an ion trap. Here, we analyze and optimize the potential distribution of an endcap ion trap for single-ion trapping.We obtain an optimal endcap radius of225 μm–250 μm, endcap-shield gap of ~ 250 μm, and inter-endcap distance of 540 μm–590 μm. The simulation method for analysis can also be applied to other ion traps, which is useful for improving the design and assembly of ion traps. 展开更多
关键词 endcap ion trap potential analysis parameter optimization
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Application Potential of Quinoa as Forage
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作者 Wei LU Jianhan HE +2 位作者 Meiyan PEI Zhimin WEI Chuan LU 《Asian Agricultural Research》 2021年第12期41-42,共2页
Quinoa is a crop as both food and forage.It has a tolerance to cold,drought,and salt.It is rich in vitamins,polyphenols,flavonoids,phytosterols and other substances,and has rich nutritional value and health care,which... Quinoa is a crop as both food and forage.It has a tolerance to cold,drought,and salt.It is rich in vitamins,polyphenols,flavonoids,phytosterols and other substances,and has rich nutritional value and health care,which provides great potential for being as forage.In this paper,the application potential and prospects of quinoa as forage are studied. 展开更多
关键词 Planting environment Nutritional value Application of forage Potential analysis
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Chemical characteristics of trace metals in PM10 and their concentrated weighted trajectory analysis at Central Delhi,India 被引量:1
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作者 Subhash Chandra Monika J.Kulshrestha +1 位作者 Ruchi Singh Nahar Singh 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第5期184-196,共13页
Trace metals associated with PM10 aerosols and their variation during day and nighttime as well as during different seasons have been studied for the year 2012. PCA analysis suggested5 PCs,which accounted for 86.8% cu... Trace metals associated with PM10 aerosols and their variation during day and nighttime as well as during different seasons have been studied for the year 2012. PCA analysis suggested5 PCs,which accounted for 86.8% cumulative variance. PC1 accounted for 30% with a significant loading of metals of anthropogenic origin,while PC2 showed 28% variance with the loading of metals of crustal origin. These trace metals showed seasonal distinct day and night time characteristics. The concentrations of Cu,Pb,and Cd were found to be higher during nighttime in all the seasons. Only Fe was observed with significantly higher mean concentrations during daytime of all seasons except monsoon. The highest mean values of Cu,Cd,Zn,and Pb during post-monsoon might be attributed to winds advection over the regions of waste/biomass burning and industrial activities in Punjab and Haryana regions.Furthermore,concentration weighted trajectory analysis suggested that metals of crustal origin were contributed by long-range transport while metals of anthropogenic and industrial activities were contributed by regional/local source regions. 展开更多
关键词 Trace metals Potential source regions Backward trajectory Principal component analysis
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Plasma Heating Device Based on Electron Beam Irradiation
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作者 Makoto Yasukagawa 《World Journal of Engineering and Technology》 2024年第4期952-962,共11页
Currently, large-scale equipment is essential for heating plasma. In this study, based on the theoretical investigation of high-current electron beam applications, a new method for heating plasma is proposed. If this ... Currently, large-scale equipment is essential for heating plasma. In this study, based on the theoretical investigation of high-current electron beam applications, a new method for heating plasma is proposed. If this method is successful, fusion power can be generated much more easily and inexpensively than using conventional methods. This study considered the theoretical possibility of generating ultrahigh-temperature plasma by confining plasma particles between the anode (positive potential) and electric fields using Rutherford scattering of particles forming a heavy-mass-positive-ion layer. In order to form this deuteron-positive ion layer, hydrogen gas is encapsulated in a closed container and applied to a negative with an insulator film on the inner surface. Next, the gas is ionized by irradiating a high-current electron. 展开更多
关键词 Rutherford Scattering Bragg Peak Potential analysis X-Ray Spectral analysis High-Current Electron Beam
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Temporal sequential correlation analysis on compoundaction potentials of the auditory nerve versus the stimulating AM-sound envelope
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作者 ZHOU Xun and LIANG Zhi’an(Shanghai Institute of Physiology Chinese Academy of Sciences Shanghai 200031) 《Chinese Journal of Acoustics》 1997年第4期356-363,共8页
Compound action potentials of the auditory nerve in response to amplitude modulating tones were recorded in guinea pigs with electrode implanted to the exit of the internal auditory meatus and temporal sequential corr... Compound action potentials of the auditory nerve in response to amplitude modulating tones were recorded in guinea pigs with electrode implanted to the exit of the internal auditory meatus and temporal sequential correlation between the responses and the modulators was studied in a paradigm of systematically changing acoustic parameters. Three kinds of modulators were used. continuous or burst sinusoids of fixed frequency (in the range of 40 Hz-5 kHz), short bursts of sinusoids with changing frequency and short segments of speech signal. Ranges of parametric variation were 500 Hz-20 kHz for carrier frequency, 5%-95% for modulation depth and 20 dB-90 dB SPL for intensity. For continuous or burst sinusoidal modulators of fixed frequencies, the correlation coefficient (r) remained quite high in most parametric conditions, ranging from 0.80 to 0.95. It became smaller mainly in instances of decreased response amplitude on account of unfavourable parameters. For burst modulators of changing frequency, r varied around 0.66-0.86. When segments of speech signal served as the modulators, significant correlation (r around 0.50 ) also existed, indicating the validity of the timing mode of information encoding for speech sound at the cochlear nerve level. Some theoretical and technical points in studying the timing mechanism of audition is discussed. 展开更多
关键词 AM Temporal sequential correlation analysis on compoundaction potentials of the auditory nerve versus the stimulating AM-sound envelope Chen kHz Rose
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Thermal and chemical analysis of massive use of hot briquetted iron inside basic oxygen furnace
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作者 Cosmo Di Cecca Silvia Barella +4 位作者 Carlo Mapelli Andrea Gruttadauria Andrea Francesco Ciuffini Davide Mombelli Enrico Bondi 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2017年第9期901-907,共7页
The integrated steelmaking cycle based on the blast furnace-basic oxygen furnace(BOF)route plays an important role in the production of plain and ultra-low carbon steel,especially for deep drawing operations.BOF ste... The integrated steelmaking cycle based on the blast furnace-basic oxygen furnace(BOF)route plays an important role in the production of plain and ultra-low carbon steel,especially for deep drawing operations.BOF steelmaking is based on the conversion of cast iron in steel by impinging oxygen on the metal bath at supersonic speed.In order to avoid the addition of detrimental chemical elements owing to the introduction of uncontrolled scrap and in order to decrease environmental impact caused by the intensive use of coke for the production of cast iron,HBI(hot briquetted iron)can be used as a source of metal and a fraction of cast iron.Forty industrial experimental tests were performed to evaluate the viability of the use of HBI in BOF.The experimental campaign was supported by a thermal prediction model and realized through the estimation of the oxidation enthalpy.Furthermore,the process was thermodynamically analyzed based on oxygen potentials using the off-gas composition and the bath temperature evolution during the conversion as reference data. 展开更多
关键词 Hot briquetted iron Basic oxygen furnace Thermal analysis Chemical analysis Oxygen potential
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From geometric to charge-distribution symmetry:deeper insights into lifting the performance of dysprosium single-ion magnets 被引量:1
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作者 Wei Deng Ying-Qian Zhou +4 位作者 Shan-Nan Du Ze-Yu Ruan Si-Guo Wu Jun-Liang Liu Ming-Liang Tong 《Science China Chemistry》 SCIE EI CAS CSCD 2023年第7期1989-1996,共8页
Crystal-field symmetry of lanthanide ions plays a critical role in suppressing quantum tunneling of magnetization(QTM)in single-molecule magnets(SMMs),but high-performance SMM design and modulation remain challenging ... Crystal-field symmetry of lanthanide ions plays a critical role in suppressing quantum tunneling of magnetization(QTM)in single-molecule magnets(SMMs),but high-performance SMM design and modulation remain challenging only in view of the geometric symmetry of the first coordination sphere.Herein,two bis(semicarbazone)/bis(thiosemicarbazone)dysprosium singleion magnets with pentagonal bipyramid geometry were reported,and bis(thiosemicarbazone)lanthanide complexes have never been reported to the best of our knowledge.They served as good archetypes to study the magneto-structural relationships based on the charge distribution.The complex with more ideal geometric symmetry displays fast zero-field QTM with negligible“effective barrier”,owing to the defective charge distribution.By modulating the transverse crystal field via the replacement of the O sites with the less charged and larger radius S atoms,it results in lower geometric but higher charge-distribution symmetry,giving rise to the significant suppression of QTM and the enhancement of reversal barrier up to ca.1,000 K.These results demonstrate that the charge-distribution symmetry can be chemically tailored by modification of the crystal field,which is essential for designing high-performance SMMs. 展开更多
关键词 single-molecule magnets crystal field symmetry strategy electrostatic potential analysis bis(thiosemicarbazone)
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Light absorption properties and potential sources of brown carbon in Fenwei Plain during winter 2018–2019 被引量:7
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作者 Wenyu Zhang Weigang Wang +10 位作者 Jie Li Shuangliang Ma Chaofan Lian Kun Li Bo Shi Mingyuan Liu Yanyu Li QingQing Wang Yele Sun Shengrui Tong Maofa Ge 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2021年第4期53-63,共11页
A distinctive kind of organic carbon aerosol that could absorb ultraviolet-visible radiation is called brown carbon(Br C),which has an important positive influence on radiative budget and climate change.In this work,w... A distinctive kind of organic carbon aerosol that could absorb ultraviolet-visible radiation is called brown carbon(Br C),which has an important positive influence on radiative budget and climate change.In this work,we reported the absorption properties and potential source of Br C based on a seven-wavelength aethalometer in the winter of 2018–2019 at an urban site of Sanmenxia in Fenwei Plain in central China.Specifically,the mean value of Br C absorption coefficient was 59.6±36.0 Mm^(-1) at 370 nm and contributed 37.7%to total absorption,which made a significant impact on visibility and regional environment.Absorption coefficients of Br C showed double-peak pattern,and Br C had shown small fluctuations under haze days compared with clean days.As for the sources of Br C,Br C absorption coefficients expressed strong correlations with element carbon aerosols and primary organic carbon aerosols,indicating that most of Br C originated from primary emissions.The linear correlations between trace metal elements(K,As,Fe,Mn,Zn,and Pb)and Br C absorption coefficients further referred that the major sources of Br C were primary emissions,like coal burning,biomass burning,and vehicle emissions.The moderate relationship between Br C absorption coefficients and secondary organic aerosols suggested that secondary production of Br C also played an important role.The 120 hr backward air mass trajectories analysis and concentration-weighted trajectories analysis were also used to investigate potential sources of Br C in and around this area,which inferred most parts of Br C were derived from local emissions. 展开更多
关键词 Brown carbon Light absorption Potential source analysis Fenwei Plain
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Local and long-range transport influences on PM_(2.5) at a cities-cluster in northern China,during summer 2008 被引量:9
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作者 Lijie Gao Yingze Tian +7 位作者 Caiyan Zhang Guoliang Shi Huize Hao Fang Zeng Chunli Shi Meigen Zhang Yinchang Feng Xiang Li 《Particuology》 SCIE EI CAS CSCD 2014年第2期66-72,共7页
Hourly PM2.5 concentrations were observed simultaneously at a cities-cluster comprising 10 cities/towns in Hebei province in China from July 1 to 31, 2008. Among the 10 cities/towns, Baoding showed the high- est avera... Hourly PM2.5 concentrations were observed simultaneously at a cities-cluster comprising 10 cities/towns in Hebei province in China from July 1 to 31, 2008. Among the 10 cities/towns, Baoding showed the high- est average concentration level (161.57μg/m3) and Yanjiao exhibited the lowest (99.35 μg/m3 ). These observed data were also studied using the joint potential source contribution function with 24-h and 72-h backward trajectories, to identify more clearly the local and countrywide-scale long-range transport sources. For the local sources, three important influential areas were found, whereas five important influential areas were defined for long-range transport sources. Spatial characteristics of PM2.5 were determined by multivariate statistical analyses. Soil dust, coal combustion, and vehicle emissions might be the potential contributors in these areas. The results of a hierarchical cluster analysis for back trajectory endpoints and PM2.s concentrations datasets show that the spatial characteristics of PM2.5 in the cities-cluster were influenced not only by local sources, but also by long-range transport sources. Different cities in the cities-cluster obtained different weighted contributions from local or long-range transport sources. Cangzhou, Shijiazhuang, and Baoding are near the source areas in the south of Hebei province, whereas Zhuozhou, Yangfang, Yanjiao, Xianghe, and Langfang are close to the sources areas near Beijing and Tianjin. 展开更多
关键词 Local mtluenceRegional influenceJoint potential source contribution functionHierarchical cluster analysis
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A quick and effective multivariate statistical strategy for imaging mass spectrometry 被引量:1
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作者 Fei Tang Yi Chen +4 位作者 Tie-Gang Li Jiu-Ming He Zeper Abliz Gang Huang Xiao-Hao Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第10期1331-1335,共5页
A new multivariate statistical strategy for analyzing large datasets that are produced by imaging mass spectrometry(IMS) techniques is reported.The strategy divides the whole datacube of the sample into several subs... A new multivariate statistical strategy for analyzing large datasets that are produced by imaging mass spectrometry(IMS) techniques is reported.The strategy divides the whole datacube of the sample into several subsets and analyses them one by one to obtain the results.Instead of analyzing the whole datacube at one time,the strategy makes the analysis easier and decreases the computation time greatly.In this report,the IMS data are produced by the air flow-assisted ionization IMS(AFAI-IMS).The strategy can be used in combination with most multivariate statistical analysis methods.In this paper,the strategy was combined with the principal component analysis(PCA) and partial least square analysis(PLS).It was proven to be effective by analyzing the handwriting sample.By using the strategy,the m/z corresponding to the specific lipids in rat brain tissue were distinguished successfully.Moreover the analysis time grew linearly instead of exponentially as the size of sample increased.The strategy developed in this study has enormous potential for searching for the mjz of potential biomarkers quickly and effectively. 展开更多
关键词 Imaging mass spectrometry Multivariate statistical analysis Potential biomarkers Quick and effective
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