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Analysis of the Impact of Off-farm Employment of Agricultural Labor on Grain Production in Shandong Province and Henan Province 被引量:3
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作者 朱琳 刘彦随 《Agricultural Science & Technology》 CAS 2012年第7期1609-1615,共7页
[Objective] This study aimed to investigate the impact of off-farm employment of agricultural labor on grain production. [Method] Impact of off-farm employment of agricultural labor on grain production was investigate... [Objective] This study aimed to investigate the impact of off-farm employment of agricultural labor on grain production. [Method] Impact of off-farm employment of agricultural labor on grain production was investigated based on path analysis by using data from 200 counties and cities in Shandong Province and Henan Province in 2000 and 2008. [Result] Off-farm employment of agricultural labor affects grain production through agricultural land use patterns, off-farm employment of agricultural labor has negative impacts on grain production through multiple cropping index and positive impacts through the proportion of grain planting area. The positive impacts were greater in 2008. [Conclusion] Prerequisite of the positive impacts of off-farm employment on grain production is the substitution of agricultural mechanization development and agricultural technology advancement for agricultural labor. Orderly land circulation and scale land use should be promoted to avoid the lack of agricultural labor due to off-farm employment. 展开更多
关键词 Off-farm employment of agricultural labor Grain Production Path analysis Shandong Province Henan Province
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WAVELET-BASED ANALYSIS OF CEREBROVASCULAR DYNAMICS IN NEWBORN RATS WITH INTRACRANIAL HEMORRHAGES 被引量:1
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作者 ALEXEY N.PAVLOV ALEXEY I.NAZIMOV +5 位作者 OLGA N.PAVLOVA VLADISLAV V.LYCHAGOV VALERY V.TUCHIN OLGA A.BIBIKOVA SERGEYS.SINDEEV OXANA V.SEMYACHKINA-GLUSHKOVSKAYA 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2014年第1期66-75,共10页
Intracranial hemorrhage(I)is a major problem of neonatal intensive care.The incidence of Iistypically asymptomatic and'canmot be effectively detected by standard diagnostic methods.The mechanisms underlying IH are... Intracranial hemorrhage(I)is a major problem of neonatal intensive care.The incidence of Iistypically asymptomatic and'canmot be effectively detected by standard diagnostic methods.The mechanisms underlying IH are unknown but there is evidence that stress-induced disorders inadrenergic regulation of cerebral venous blood flow (CVBF) are among the main reasons.Quantitative and qualitative:could significantly advance understanding ofthe nature of I in newbornslth1sions of CVBF in newborn rats withan experimental model of stinjection.Our analysis is bas ed on theDoppler optical coheavelet-based approachthat provides sensitiv external factors.Theobtained resultsccompanied by asupprectivity to adrenaline.Weintroducd show that the values0<1.23 estimated ithelodinto the sympathicusindicate abnormal reactions associated with the developent of I.We conclude that t he revealed areactivity of the cerebral veins to adrenaline represents a possible mechanism responsible forpat hological changes in CVBF. 展开更多
关键词 Brain hemorhages optical coherence tomography cerebrovascular dynamics wavelet analy sis stress.
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Identification of distant co-evolving residues in antigen 85C from Mycobacterium tuberculosis using statistical coupling analysis of the esterase family proteins 被引量:2
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作者 Veeky Baths Utpal Roy 《The Journal of Biomedical Research》 CAS 2011年第3期165-169,共5页
A fundamental goal in cellular signaling is to understand allosteric communication, the process by which sig-nals originating at one site in a protein propagate reliably to affect distant functional sites. The general... A fundamental goal in cellular signaling is to understand allosteric communication, the process by which sig-nals originating at one site in a protein propagate reliably to affect distant functional sites. The general principles of protein structure that underlie this process remain unknown. Statistical coupling analysis (SCA) is a statistical technique that uses evolutionary data of a protein family to measure correlation between distant functional sites and suggests allosteric communication. In proteins, very distant and small interactions between collections of amino acids provide the communication which can be important for signaling process. In this paper, we present the SCA of protein alignment of the esterase family (pfam ID: PF00756) containing the sequence of antigen 85C secreted by Mycobacterium tuberculosis to identify a subset of interacting residues. Clustering analysis of the pairwise correlation highlighted seven important residue positions in the esterase family alignments. These resi-dues were then mapped on the crystal structure of antigen 85C (PDB ID: 1DQZ). The mapping revealed corre-lation between 3 distant residues (Asp38, Leu123 and Met125) and suggests allosteric communication between them. This information can be used for a new drug against this fatal disease. 展开更多
关键词 antigen 85C Mycobacterium tuberculosis clustering analysis COVARIANCE statistical coupling analy-sis esterase family multiple sequence alignments PFAM Protein Data Bank.
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基于SIS模型的群体社交网络舆情演化仿真
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作者 路苗 门可 +2 位作者 马永红 张海瑞 冯彦成 《吉林大学学报(信息科学版)》 CAS 2023年第1期106-111,共6页
针对群体社交网络舆情演化时,目前方法获取关键节点中的数据较为困难,导致无法准确获得舆情传播次数、搜索指数、达到舆情峰值所用时间等参数,存在演化精度低的问题,提出基于聚类算法与易感-感染-易感(SIS:Susceptible Infected Suscept... 针对群体社交网络舆情演化时,目前方法获取关键节点中的数据较为困难,导致无法准确获得舆情传播次数、搜索指数、达到舆情峰值所用时间等参数,存在演化精度低的问题,提出基于聚类算法与易感-感染-易感(SIS:Susceptible Infected Susceptible Model)模型的群体社交网络舆情演化仿真方法。在群体社交网络中采用PageRank算法获取关键节点,利用聚类算法对关键节点中的数据聚类进行处理,在此基础上构建SIS模型,并通过其完成群体社交网络的舆情演化仿真。实验结果表明,该方法可准确地获得舆情传播次数、搜索指数、达到舆情峰值所用时间等参数,演化仿真精度高。 展开更多
关键词 聚类算法 sis模型 关键节点识别 PAGERANK算法 网络舆情演化
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ArcGIS<sup>TM</sup>and Principal Component Analysis of Probe Data to Micro-Map Minerals in Round Top Rare Earth Deposit
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作者 Lorraine M. Negrón Margaret Piranian +2 位作者 Maria A. Amaya Daniel Gorski Nicholas E. Pingitore 《Advances in Materials Physics and Chemistry》 2020年第2期39-52,共14页
Rare earth elements (REEs), especially heavy rare earth elements (HREEs), are in demand for their current and emerging applications in advanced technologies. Here we perform computer-driven micro-mapping at the millim... Rare earth elements (REEs), especially heavy rare earth elements (HREEs), are in demand for their current and emerging applications in advanced technologies. Here we perform computer-driven micro-mapping at the millimeter scale of the minerals that comprise Round Top Mountain, in west Texas, USA. This large rhyolite deposit is enriched in HREEs and such other critical elements as Li, Be, and U. Electron probe microanalysis of 2 × 2 mm areas of thin sections of the rhyolite produced individual maps of 16 elements. These were superimposed to generate a 16-element composition at each pixel. Principal components analysis of elements at each pixel identified the specific mineral at that site. The pixels were then relabeled as the appropriate minerals, thereby producing a single mineral map. The overall mineral composition of the 7 studied samples compared favorably with prior analyses of the Round Top deposit available in the literature. Likewise the range of porosity in the maps was consistent with that of previous direct measurements by water saturation. This new statistical and GIS-based technique provides a robust and unbiased approach to electron microprobe mapping. The study further showed that the high-value yttrofluorite grains exhibited little tendency to cluster with other late-stage trace minerals and that the samples extended the previously documented overall homogeneity of the deposit at field scale to this microscopic scale. 展开更多
关键词 ArcGISTM Electron Probe MICROanalysis Principal Component analy-sis Rare Earths Yttrofluorite X-Ray MAP analyzer ROUND TOP
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Effects of Pre-Strain on Bake Hardenability and Precipitation Behavior of Al-Mg-Si Automotive Body Sheets
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作者 Guanjun Gao Lizhen Yan Xiwu Li 《Journal of Materials Science and Chemical Engineering》 2024年第7期53-64,共12页
The study investigates the effects of pre-strain on the bake hardenability and precipitation behavior of Al-Mg-Si automotive body sheets. The scanning electron microscopy, transmission electron microscopy, tensile tes... The study investigates the effects of pre-strain on the bake hardenability and precipitation behavior of Al-Mg-Si automotive body sheets. The scanning electron microscopy, transmission electron microscopy, tensile test, Vickers hardness test, and differential scanning calorimetry were conducted for the purpose. It was found that the pre-strain treatment partially inhibits the natural aging hardening effect but cannot completely eliminate it. The pre-straining significantly enhances the bake hardening effect, with the 5% pre-strain sample showing the highest increase in yield strength and hardness. The formation of fine β" precipitates and dislocation structures contribute to the observed strengthening. Additionally, the study highlights the importance of optimizing pre-strain levels to achieve the best balance between strength and ductility in bake-hardened aluminum alloys. 展开更多
关键词 Al-Mg-si Alloy PRE-STRAIN Bake Hardenability Precipitation Behavior clusterS
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基于熵权TOPSIS法的房地产业对新型城镇化通径分析——以海南省五指山市为例 被引量:5
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作者 庄海燕 《地域研究与开发》 CSSCI CSCD 北大核心 2017年第4期78-82,104,共6页
以21世纪以来特别是"十二五"时期新型城镇化与房地产相关数据为样本,运用改进的熵权TOPSIS法对新型城镇化质量综合测度,采用通径分析法研究五指山市房地产各指标对新型城镇化的影响作用程度。结果表明:2009—2014年五指山的... 以21世纪以来特别是"十二五"时期新型城镇化与房地产相关数据为样本,运用改进的熵权TOPSIS法对新型城镇化质量综合测度,采用通径分析法研究五指山市房地产各指标对新型城镇化的影响作用程度。结果表明:2009—2014年五指山的新型城镇化质量综合水平呈现稳步上升状态,始终处于中级与良好状态;2014年新型城镇化各指标发展程度由小到大依次为人口城镇化、土地城镇化、经济城镇化、生活城镇化和社会城镇化,人口与土地始终是制约五指山新型城镇化快速发展的关键因素;商品房销售均价、房地产开发投资额、经济适用房总计划投资额与新型城镇化呈正相关,对新型城镇化的影响作用依次减小,新开工房屋面积与新型城镇化质量呈负相关,但影响作用程度较微弱。 展开更多
关键词 房地产 新型城镇化 TOPsis 改进的熵值法 通径分析 五指山市
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Stress Physiology and Virulence Characterization of Phomopsis asparagi (Sacc.) Bubák isolated from Asparagus in Jiangxi Province of China
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作者 张岳平 陈光宇 +4 位作者 罗绍春 瞿华香 汤泳萍 谢启鑫 周劲松 《Agricultural Science & Technology》 CAS 2012年第7期1502-1508,共7页
Fungal pathogen of asparagus stem blight was isolated. No significant genetic difference was detected among the three strains with 492 bp long ITS1-5.8S-ITS2 sequence. It was then identified through colony growth, con... Fungal pathogen of asparagus stem blight was isolated. No significant genetic difference was detected among the three strains with 492 bp long ITS1-5.8S-ITS2 sequence. It was then identified through colony growth, conidia morphology, and molecular characterization. The physiological response to oxidation and osmosis stress, and virulence to Asparagus officinalis L. were analyzed. The results showed that the pathogen causing asparagus stem blight for A. officinalis L. in Jiangxi Province is Phomopsis asparagri (Sacc.) Bubák. Under pure culture conditions, the conidia were oval-shaped (α-type), with colorless single spore and single nucleus, containing 0-2 oil balls. Its vegetative growth rate was higher when cultured on 0.2 × potato dextrose agar (0.2 × PDA) medium than that on oatmeal agar (OA) medium. However, the pycnidia appeared earlier on OA medium than on 0.2 earlier PDA medium. The vegetative growth rate was depressed under oxidation (H2O2) or osmosis (NaCl) stress conditions, and totally inhibited under 7 mmol/L H2O2 or 2.4 mol/L NaCl. All the strains caused typical pathogenic symptoms to Asparagus officinalis L. at 7 days-post-inoculation (dpi) with conidia. 展开更多
关键词 Asparagus officinalis L. Phomopsis asparagri (Sacc.) Bubák ITS analysis STRESS VIRULENCE
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基于TOPSIS对宜居城市的模糊综合评价 被引量:5
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作者 张月蕾 朱家明 《哈尔滨商业大学学报(自然科学版)》 CAS 2018年第4期508-512,共5页
宜居城市的构建已经成为当前国内外城市追求的目标,也是当前国内外城市研究的热点.针对淮海经济区的徐州、连云港、宿迁、商丘、济宁、宿州、枣庄和淮北这八座城市的宜居水平进行分析,建立综合评价衡量城市宜居水平的指标体系,并利用层... 宜居城市的构建已经成为当前国内外城市追求的目标,也是当前国内外城市研究的热点.针对淮海经济区的徐州、连云港、宿迁、商丘、济宁、宿州、枣庄和淮北这八座城市的宜居水平进行分析,建立综合评价衡量城市宜居水平的指标体系,并利用层次分析法计算城市宜居水平的综合得分,同时利用TOPSIS考虑不确定因素对宜居城市评价稳定性的影响.最后根据八个城市宜居城市的综合得分,给出排名,结合实际给出相关建议. 展开更多
关键词 宜居城市 AHP 模糊综合评价 主成分分析 TOPsis SPSS
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Oxidation Effects on the Electronic Properties of Hydrogenated Silicon Clusters 被引量:1
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作者 刘光华 邓小燕 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第5期762-768,共7页
The geometric and electronic properties of some hydrogenated silicon clusters in the presence of oxygen on the surface have been investigated.The density functional theory with generalized gradient approximation funct... The geometric and electronic properties of some hydrogenated silicon clusters in the presence of oxygen on the surface have been investigated.The density functional theory with generalized gradient approximation functional was applied in our calculations.By calculating the total energy,the double bond Si=O is shown to be more stable than the bridge bond Si-O-Si for large size oxidized clusters.The results of Mulliken population analysis indicate that a so-called passivation effect is enhanced by oxidization effects.From the energy band structures and density of states,we find that some localized states are induced by the p-orbital of O atom mainly and reduce the energy gaps substantially. 展开更多
关键词 hydrogenated si cluster oxidation effects density functional theory
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Theoretical Study on the Structure and Stability of Si_5X (X = Li, Be, B, C, N, O, F, Na, Mg, Al, Si, P, S, Cl) Clusters
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作者 张宏 孙仁安 +1 位作者 李纳 阎杰 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第3期279-284,共6页
Density functional theory B3LYP/6-311 G* method was used in the geometry optimization and frequency calculation on Si5X (X = Li, Be, B, C, N, O, E Na, Mg, Al, Si, P, S, Cl) clusters. The influence of the doped seco... Density functional theory B3LYP/6-311 G* method was used in the geometry optimization and frequency calculation on Si5X (X = Li, Be, B, C, N, O, E Na, Mg, Al, Si, P, S, Cl) clusters. The influence of the doped second and third period element impurities on the structure and stability of Si5X clusters with C2p symmetry has been investigated, and the thermal stability and dynamic activity have also been discussed. 展开更多
关键词 si clusters theoretical study DFT theory
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Theoretical Study on the Structure and Stability of Si_4X (X = Li, Be, B, C, N, O, F) Clusters
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作者 孙仁安 李钠 张旭 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第12期1383-1387,共5页
The density functional theory B3LYP/6-311g* method is used in the geometry optimization and frequency calculation on Si4X (X = Li, Be, B, C, N, O, F) clusters. The equi- librium structures of these clusters are quas... The density functional theory B3LYP/6-311g* method is used in the geometry optimization and frequency calculation on Si4X (X = Li, Be, B, C, N, O, F) clusters. The equi- librium structures of these clusters are quasi-trigonal bipyramidal structures with C2v symmetry. The periodicity of their thermal stabilities and vibration spectra has been discussed. The influence of the inserted second period element impurities for the structures and stabilities of the Si5 clusters have also been investigated. 展开更多
关键词 si clusters theoretical study density functional theory
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Electronic and Optical Properties of Hydrogenated Si Clusters
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作者 刘光华 邓小燕 王秀清 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第9期1093-1098,共6页
The geometric, electronic, and photoabsorption properties of some hydrogenated silicon clusters are investigated. The density functional theory with generalized gradient approximation fimctional is applied. Our study ... The geometric, electronic, and photoabsorption properties of some hydrogenated silicon clusters are investigated. The density functional theory with generalized gradient approximation fimctional is applied. Our study shows that the geometric structures of them relax with their increasing sizes. Synchronously, the polarizations of Si-H bonds become weak slowly but overlap populations increase. In Mulliken population analysis, we find a distinctive passivation effect (some electrons are transferred from outer Si atoms to the central Si with four-coordinate Si atoms). Owing to the quantum confinement, the energy gap and the lowest excitation energy increase with the decreasing sizes. For nanometer scale cluster, the transition from the highest occupied molecular orbital to the lowest unoccupied molecular orbital state is usually prohibited. 展开更多
关键词 hydrogenated si cluster density functional theory passivation effect
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Formation and local electronic structure of Ge clusters on Si(111)-7×7 surfaces
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作者 马海峰 徐明春 +4 位作者 杨冰 时东霞 郭海明 庞世瑾 高鸿钧 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第9期2661-2664,共4页
We report the formation and local electronic structure of Ge clusters on the Si(111)-7×7 surface studied by using variable temperature scanning tunnelling microscopy (VT-STM) and low-temperature scanning tunn... We report the formation and local electronic structure of Ge clusters on the Si(111)-7×7 surface studied by using variable temperature scanning tunnelling microscopy (VT-STM) and low-temperature scanning tunnelling spectroscopy (STS). Atom-resolved STM images reveal that the Ce atoms are prone to forming clusters with 1.0 nm in diameter for coverage up to 0.12 ML. Such Ce clusters preferentially nucleate at the centre of the faulted-half unit cells, leading to the 'dark sites' of Si centre adatoms from the surrounding three unfaulted-half unit cells in filled-state images. Biasdependent STM images show the charge transfer from the neighbouring Si adatoms to Ce clusters. Low-temperature STS of the Ce clusters reveals that there is a band gap on the Ce cluster and the large voltage threshold is about 0.9 V. 展开更多
关键词 scanning tunnelling microscopy si(111)-7× 7 surface Ge cluster
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Cluster and Condensed Phase Properties of Light Elements (especially B, C, N, Na and Si)
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作者 N.H.Marcn(Oxford University Oxford, England) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1997年第4期241-244,共4页
Amorphous forms of C will first be compared and contrasted with amorphous Si, the differences in chemical bonding being emphasized in relation to atomic structure. After a brief discussion of ordered layers of graphit... Amorphous forms of C will first be compared and contrasted with amorphous Si, the differences in chemical bonding being emphasized in relation to atomic structure. After a brief discussion of ordered layers of graphite and of BN, some attention will be focused on BN cages and polymers and on C nanotubes. Finally properties of Na metal clusters will be discussed, including fission of such charged clusters 展开更多
关键词 si especially B REV FIGURE cluster and Condensed Phase Properties of Light Elements Na and si
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火力发电厂厂级监控信息系统(SIS)的设计应用 被引量:1
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作者 罗立旻 方波 闻杰 《能源与节能》 2012年第4期24-25,29,共3页
叙述了电厂厂级监控信息系统的一般组成部分,重点介绍该系统的设计思路。
关键词 sis 实时数据库 集群
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The Cluster Fe<sub>2</sub>Si<sub>18</sub>as the New Quantum Bit System
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作者 K. V. Simon A. V. Tulub 《Computational Chemistry》 2015年第2期23-28,共6页
Multiconfiguration quantum chemical calculation of geometry and electron properties of Fe2Si18 cluster indicates on the predictable change of spin states as a function of the excitation energy beginning from ground st... Multiconfiguration quantum chemical calculation of geometry and electron properties of Fe2Si18 cluster indicates on the predictable change of spin states as a function of the excitation energy beginning from ground state with the total spin S = 4. The charges on the two Fe atoms are quite different as well as the charge distribution on the surrounding Si atoms. Nevertheless the total dipole moment of the cluster is a monotonically decreasing function of the excitation energy and it reaches practically zero value in the first singlet state in which the cluster represents a new version of a quibit system. 展开更多
关键词 multiconfigurational quantum theory ground and EXCITED electronic states iron-silicon Fe2si18 cluster two-state system.
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Efficiently Adsorbing CO Molecules Using Al_6Si Cluster
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作者 黎康宁 杨传路 +1 位作者 王美山 马晓光 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第9期1355-1361,共7页
Based on the density functional theory with generalized gradient approximation, the stable geometrical structures of one or more CO molecules adsorbed on the Al6Si cluster are investigated and the corresponding adsorp... Based on the density functional theory with generalized gradient approximation, the stable geometrical structures of one or more CO molecules adsorbed on the Al6Si cluster are investigated and the corresponding adsorption energies are also calculated. It is found that the cluster Al6Si can adsorb six CO molecules. The thermal stability of the(CO)6@Al6Si complexes is examined using the atom centered density matrix propagation molecular dynamics calculations at 373 K. The results show that two isomers of Al6Si cluster can solidly adsorb six CO molecules, and the other isomer adsorbs four ones. Therefore, the Al6Si cluster is a promising candidate for eliminating CO effectively. 展开更多
关键词 adsorption thermal stability CO molecule Al6si cluster
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基于虚拟化技术升级改造SIS系统
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作者 袁小勃 《电脑与信息技术》 2017年第3期54-56,共3页
自虚拟化技术诞生以来,并随着信息技术的发展,虚拟化技术掀起了发展高潮。在首阳山电厂SIS硬件系统升级改造过程中,采用基于虚拟化技术构建并替代SIS传统意义上的升级改造。实践证明,采用基于虚拟化技术升级改造的SIS生产环境,有效减少... 自虚拟化技术诞生以来,并随着信息技术的发展,虚拟化技术掀起了发展高潮。在首阳山电厂SIS硬件系统升级改造过程中,采用基于虚拟化技术构建并替代SIS传统意义上的升级改造。实践证明,采用基于虚拟化技术升级改造的SIS生产环境,有效减少了IT设备的投入,显著降低了生产管理成本,值得推广。 展开更多
关键词 虚拟化 VMWARE sis 群集
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寒地杏种质资源果实性状评价及优异鲜食资源筛选 被引量:1
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作者 陈蕾 赵慧 +3 位作者 刘禹夫 张瀚竹 张艳波 侯佳贤 《北方园艺》 CAS 北大核心 2024年第8期20-26,共7页
以29份寒地杏种质资源为试材,测定果实23个质量性状和6个数量性状并进行分析评价,以期为深入了解寒地杏种质资源遗传多样性、挖掘和高效利用杏资源提供参考依据。结果表明:29份资源数量性状中果实硬度和单果质量变异系数最大,分别为68.... 以29份寒地杏种质资源为试材,测定果实23个质量性状和6个数量性状并进行分析评价,以期为深入了解寒地杏种质资源遗传多样性、挖掘和高效利用杏资源提供参考依据。结果表明:29份资源数量性状中果实硬度和单果质量变异系数最大,分别为68.35%和40.32%,单果质量和核鲜质量呈显著正相关;质量性状的多样性指数变化范围为0.2732~1.6731,果形多样性指数最高,为1.6731,风味和果实颜色的多样性指数分别为1.2049和1.1919,说明杏资源表型多样性较为丰富;主成分分析表明前8个主成分能代表23个描述型性状的大部分信息,累计方差贡献率达77.789%;筛选出6份优异鲜食杏资源,分别为‘丹麦黄杏’‘双山杏’‘桦甸杏’‘白杏1’‘九台晚杏’‘桦甸红杏’。 展开更多
关键词 质量性状 数量性状 相关性分析 主成分分析
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