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Effect of noncovalent complexations on coordination interactions in a tricomponent system ofβ-cyclodextrin,copper chloride and hexamethylene tetramine

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Chinese Chemical Letters 2011年第11期22卷 1347-1350页

作者： Jing Yang Le Xin Song Zheng dang shu Zhen Pan Fang Yun Du Department of Chemistry University of Science and Technology of China Hefei 230026 China State Key Laboratory of Coordination Chemistry Nanjing University Nanjing 210093 China

This study reveals that the noncovalent complexation betweenβ-CD and Cu（HMTA）^（2＋） makes a positive contribution to the coordination interaction between Cu^（2＋） and HMTA in a tricomponent ***,mono- and binucl... 详细信息

关键词： Noncovalent complexation Coordination interaction β-Cyclodextrin Copper chloride

Micro-pore Structure and Gas Accumulation Characteristics of Shale in the Longmaxi Formation, Northwest Guizhou

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Petroleum Research 2016年第2期1卷 191-204页

作者： Bing Xue Jinchuan Zhang xuan Tang Chao Yang Qian Chen Xiangjie Man Wei dang School of Energy Resources China University of GeosciencesBeijing 100083China Key Laboratory of Shale Gas Exploration and Evaluation Ministry of Land and ResourcesBeijing 100083China CNPC Greatwall Drilling Company Beijing 100101China

For further study on characteristics of micro-pores in the marine shale reservoirs in Northwest Guizhou,shale samples in the Lower Silurian Longmaxi Formation were selected to investigate effect of micro-pores on the characteristics of gas accumulation in shales,through methods of the argon broad ion beam-field emission scanning electron microscope and the nitrogen adsorption/desorption,analysis on the characteristics of micro-pores and related geochemical *** show that there are seven types of pores in the Longmaxi Formation shale,including interparticle pores,intraparticle pores,intercrystalline pores,dissolution pores,fossil pores,organic pores,and microfractures,among which the interparticle pores and organic pores are best *** to the nitrogen adsorption/desorption curves,the pore structures can be classified into three types,including the cylindrical pores with both opening ends,narrow parallel-plate pores and tapered parallel-plate pores with four opening *** of micro-pores ranges from 2 to 64 nm,mainly at 2-6 *** diameter of micro-pores(less than 2 nm)ranges from 0.4 to 1.8 nm,The micro-pores with a diameter of 0.4-1.0 nm contribute most to the pore *** volume is dominated by meso-pores(2-50 nm)with a proportion of 83.1%.The micro-pores and meso-pores make major contribution to the specific surface area of pores with proportions of 20.1%and 79.3%,*** total organic carbon(TOC)is the major factor controlling development of *** pore types have different characteristics of gas occurrence and migration,indicating that nanopores provide favorable conditions for the occurrence and microscopic migration of gas in shales.

关键词： Northwest Guizhou Longmaxi Formation lower Silurian argon broad ion beam-field emission scanning electron microscope nitrogen adsorption/desorption pore structure

Habitat heterogeneity and biotic interactions mediate climate influences on seedling survival in a temperate forest

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Forest Ecosystems 2023年第5期10卷 579-588页

作者： Haikun Liu Hang Shi Quan Zhou Man Hu Xiao shu Kerong Zhang Quanfa Zhang Haishan dang Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical GardenChinese Academy of SciencesWuhan430074China University of Chinese Academy of Sciences Beijing100049China

Seedling stage has long been recognized as the bottleneck of forest regeneration,and the biotic and abiotic processes that dominate at seedling stage largely affect the dynamics of *** might be particularly vulnerable to climate stress,so elucidating the role of interannual climate variation in fostering community dynamics is crucial to understanding the response of forest to climate *** seedling survival data of 69 woody species collected for five consecutive years from a 25-ha permanent plot in a temperate deciduous forest,we identified the effects of biotic interactions and habitat factors on seedling survival,and examined how those effects changed over *** found that interannual climate variations,followed by biotic interactions and habitat conditions,were the most significant predictors of seedling *** light showed a positive impact on seedling mortality,and seedling survival responded differently to soil and air *** of conspecific neighbor density were significantly strengthened with the increase of maximum air temperature and vapor pressure deficits in the growing season,but were weakened by increased maximum soil temperature and precipitation in the non-growing ***,seedling survival was strongly correlated with interannual climate variability at all life stages,and the strength of the correlation increased with seedling *** addition,the importance of biotic and abiotic factors on seedling survival differed significantly among species-trait ***,the neighborhood-mediated effects on mortality might be significantly contributing or even inverting the direct effects of varying abiotic conditions on seedling survival,and density-dependent effects could not be the only important factor influencing seedling survival at an early stage.

关键词： Seedling survival Extreme interannual climate Negative density-dependence Species coexistence

Patterns of species diversity and its determinants in a temperate deciduous broad-leaved forest

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Forest Ecosystems 2022年第5期9卷 647-656页

作者： Rui He Man Hu Hang Shi Quan Zhou Xiao shu Kerong Zhang Quanfa Zhang Haishan dang Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical GardenChinese Academy of SciencesWuhan430074China University of Chinese Academy of Sciences Beijing100049China

Biodiversity conservation has long been a subject of extreme interest to community ecologists,with a particular focus on exploring the underlying causes of species diversity based on niche and neutral *** study aims to identify the potential determinants of species diversity in a deciduous broad-leaved forest in the transitional region from subtropical to temperate climate in *** collected woody plant data and environmental variables in a fully mapped 25-ha permanent forest plot,partitioned the beta-diversity into local contributions(LCBD)and species contributions(SCBD),and then applied multivariate linear regression analysis to test the effects of biotic and abiotic factors on alpha-diversity,LCBD,and *** used variation partitioning in combination with environmental variables and spatial distance to determine the contribution of environment-related variations versus spatial *** results showed that the indices of alpha-diversity(i.e.,species abundance and richness)were positively correlated with soil available phosphorus(P)and negatively with *** the betadiversity,environment and space together explained nearly half of the variations in community *** 60%of the variation of LCBD in the understory layer,40%in the substory layer,and 29%in the canopy layer were jointly explained by topographic,soil and biological variables,with biotic factors playing a dominant role in determining the *** abundance accounted for a large proportion of the variations in SCBD in each vertical stratum,and niche position(NP)was the ecological trait that significantly affected the variations in SCBD in the substory and canopy *** findings help to gain better understanding on how species diversity in forest ecosystem responds to environmental conditions and how it is influenced by biotic factors and ecological traits of species.

关键词： Alpha-diversity Beta-diversity Vertical strata Multivariate linear regression

Energy saving by using asymmetric aftbodies for merchant ships–design methodology, numerical simulation and validation

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Journal of Hydrodynamics 2016年第6期28卷 1022-1028页

作者： Jie dang 陈灏 Maritime Research Institute Netherlands (MARIN) Wageningen The Netherlands Guangzhou Shipyard International Company Ltd. Guangzhou 510382 China

The methodology and procedures are discussed on designing merchant ships to achieve fully-integrated and optimized hull-propulsion systems by using asymmetric aftbodies. Computational fluid dynamics （CFD） has been used to evaluate the powering performance through massive calculations with automatic deformation algorisms for the hull forms and the propeller blades. Comparative model tests of the designs to the optimized symmetric hull forms have been carried out to verify the efficiency gain. More than 6% improvement on the propulsive efficiency of an oil tanker has been measured during the model tests. Dedicated sea-trials show good agreement with the predicted performance from the test results.

关键词： energy saving hull form asymmetric aftbody model tests sea trials

A SIMPLICIAL ALGORITHM FOR COMPUTING AN INTEGER ZERO POINT OF A MAPPING WITH THE DIRECTION PRESERVING PROPERTY

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Journal of Computational Mathematics 2006年第6期24卷 711-718页

作者： Chuang-yin dang Department of Manufacturing Engineering and Engineering Management City University of Hong Kong Kowloon Hong Kong

A mapping f ： Z^n → Rn is said to possess the direction preserving property if fi（x）〉 0 implies fi（y） ≥ 0 for any integer points x and y with ｜｜x - y｜｜∞≤ 1. In this paper, a simplicial algorithm is developed for computing an integer zero point of a mapping with the direction preserving property. We assume that there is an integer point x^0 with c ≤ x^0≤d satisfying that maxl≤i≤（xi - xi^0）fi（x）〉 0 for any integer point x with f（x） ≠ 0 on the boundary of H = {x ∈R^n [c-e ≤ x〈d＋e},wherecanddaretwo finite integer points with c 〈 d and e = （1, 1,... , 1）^T E R^n. This assumption is implied by one of two conditions for the existence of an integer zero point of a mapping with the preserving property in van der Laan et al. （2004）. Under this assumption, starting at x^0, the algorithm follows a finite simplicial path and terminates at an integer zero point of the mapping. This result has applications in general economic equilibrium models with indivisible commodities.

关键词： Integer Zero Point Direction Preserving Simplicial Algorithm Triangulation,Existence.

Disparities in tree mortality among plant functional types(PFTs)in a temperate forest:Insights into size-dependent and PFT-specific patterns

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Forest Ecosystems 2024年第4期11卷 480-490页

作者： Man Hu Hang Shi Rui He Bingbin Wen Haikun Liu Kerong Zhang Xiao shu Haishan dang Quanfa Zhang Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical GardenChinese Academy of SciencesWuhan 430074China Danjiangkou Wetland Ecosystem Field Scientific Observation and Research Station Chinese Academy of Sciences&Hubei ProvinceWuhan 430074China University of Chinese Academy of Sciences Beijing 100049China Forest&Nature Lab Department of EnvironmentGhent UniversityGeraardsbergsesteenweg 267Melle-Gontrode9090Belgium

Tree mortality significantly influences forest structure and function,yet our understanding of its dynamic patterns among a range of tree sizes and among different plant functional types(PFTs)remains *** study analysed size-dependent tree mortality in a temperate forest,encompassing 46 tree species and 32,565 individuals across different PFTs(i.e.,evergreen conifer *** broadleaf species,shade-tolerant ***-intolerant species).By employing all-subset regression procedures and logistic generalized linear mixed-effects models,we identified distinct mortality patterns influenced by biotic and abiotic *** results showed a stable mortality patte rn in eve rgreen conifer species,contrasted by a declining pattern in deciduous broadleaf and shadetolerant,as well as shade-intolerant species,across size *** contribution to tree mortality of evergreen conifer species shifted from abiotic to biotic factors with increasing size,while the mortality of deciduous broadleaf species was mainly influenced by biotic factors,such as initial diameter at breast height(DBH)and conspecific negative *** shade-tolerant species,the mortality of small individuals was mainly determined by initial DBH and conspecific negative density dependence,whereas the mortality of large individuals was subjected to the combined effect of biotic(competition from neighbours)and abiotic factors(i.e.,convexity and pH).As for shade-intolerant species,competition from neighbours was found to be the main driver of tree mortality throughout their growth ***,these insights enhance our understanding of forest dynamics by revealing the size-dependent and PFT-specific tree mortality patterns,which may inform strategies for maintaining forest diversity and resilience in temperate forest ecosystems.

关键词： Size-dependent tree mortality Plant functional type Neighbourhood competition Topography variables Soil properties

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压电陶瓷执行器的神经网络实时自适应逆控制

光学精密工程 2008年第7期16卷 1266-1272页

作者：党选举桂林电子科技大学智能系统与工业控制研究室广西桂林541004

提出了基于内积的压电陶瓷动态神经网络非线性、非光滑迟滞逆模型,采用反馈误差学习方法,快速地在线得到压电陶瓷的逆模型,避免了通过正模型求取压电陶瓷的Jacobian信息。结合PID反馈控制,在dSPACE系统平台上实现了压电陶瓷的神经网络... 详细信息

提出了基于内积的压电陶瓷动态神经网络非线性、非光滑迟滞逆模型,采用反馈误差学习方法,快速地在线得到压电陶瓷的逆模型,避免了通过正模型求取压电陶瓷的Jacobian信息。结合PID反馈控制,在dSPACE系统平台上实现了压电陶瓷的神经网络自适应逆控制。为提高实时性,采用了效率高、速度快的C-MEX S Function编程。实验结果表明:神经网络自适应逆控制的控制精度为0.13μm,而PID控制精度为0.32μm。所提出方法有效地消除了迟滞的影响,控制精度高。

关键词：匪电陶瓷迟滞特性神经网络自适应逆控制 dSPACE系统非光滑迟滞逆模型

Friction and wear properties of N+ ion implanted nylon 1010

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 274-277页

作者： XIONG dang-sheng Department of Materials Science & Engineering Nanjing University of Science and Technology Nanjing 210094 China

The PA1010 was implanted with 450 keV N+ ions to three doses of 5× 1014 cm-2 , 2.5× 1015 cm-2 and 1.25 × 1016 cm-2. The friction and wear behaviors of the ion implanted PA1010 disks rubbing with two ceramic (ZrO2 and Si3N4) balls were studied using a pin-on-disk tribometer under dry friction. The results shows that the wear resistance of PA1010 is increased with the increasing implantation doses. The adhesion, plastic deformation and plow groove are wearing mechanisms for un-implanted PA1010, while abrasive wear for implanted PA1010.

关键词： ion implanted PA1010 tribological properties