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海外学者对中国社会关系网络的研究 被引量:3
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作者 刘娜 《青海社会科学》 CSSCI 2014年第2期77-83,共7页
随着社会网络研究的兴起,海外学者对中国社会关系网络的研究也是方兴未艾。本文比较全面地搜集了该领域的英文文献,希望通过细致的文献梳理工作将这些独立的研究缀合成一个有机的整体,以使大家对国外同行的研究有一个全面、深入的了解... 随着社会网络研究的兴起,海外学者对中国社会关系网络的研究也是方兴未艾。本文比较全面地搜集了该领域的英文文献,希望通过细致的文献梳理工作将这些独立的研究缀合成一个有机的整体,以使大家对国外同行的研究有一个全面、深入的了解与认识。海外学者们在对中国的社会关系网络进行研究时,采用的大多不是西方通用的social networks而是"Guanxi"(关系)这一极具中国文化内涵的概念。"关系"兼具情感性与工具性,是一种被道德和情感所强化的互惠的、具有持久性的联系。在具体研究中,学者们大多将研究重点放在对网络动员和资源获取过程的动态分析上。虽然社会网络可以为行动者的行动赋权增能,但其作用不应被过分夸大。行动者所能达成的目标在很大程度上受到他们自身社会位置的影响与制约。 展开更多
关键词 “Guanxi”(关系) 网络动员 资源获得 结构性因素
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“因为时间关系”语义隐含偏向研究 被引量:1
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作者 刘宗保 《新疆大学学报(哲学社会科学版)》 CSSCI 2019年第2期138-142,共5页
"因为时间关系"表达中有偏向消极的语义隐含,这可以通过将"因为时间关系"还原为"因为时间VP"后VP的语义偏向,以及将"因为时间VP"转换为"因为时间关系"的可接受度得到证明。这一表达... "因为时间关系"表达中有偏向消极的语义隐含,这可以通过将"因为时间关系"还原为"因为时间VP"后VP的语义偏向,以及将"因为时间VP"转换为"因为时间关系"的可接受度得到证明。这一表达使用的语用动因是信息推理的可及性及"原因"信息的凸显程度,其隐含偏向的形成是"偏向常态"原则与"时间"语义偏移的语用机制合力的结果。 展开更多
关键词 因为时间关系 语义隐含偏向 “偏向常态”原则 语义偏移
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半定锥上的凸关系探讨
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作者 燕子宗 张宝琪 《长江大学学报(自科版)(上旬)》 CAS 2007年第2期1-3,共3页
锥序关系是一种特殊的序关系,利用它建立更一般的锥凸性,可以获得许多重要的矩阵不等式。研究了一元凸函数诱导的锥凸关系,得到分块矩阵在正交变换下保持某种锥序关系。并从一元凸函数诱导的锥凸关系出发,对一般的锥凸函数进行了简单讨... 锥序关系是一种特殊的序关系,利用它建立更一般的锥凸性,可以获得许多重要的矩阵不等式。研究了一元凸函数诱导的锥凸关系,得到分块矩阵在正交变换下保持某种锥序关系。并从一元凸函数诱导的锥凸关系出发,对一般的锥凸函数进行了简单讨论,并利用锥凸关系简单地证明了一些重要的矩阵不等式。 展开更多
关键词 凸函数 锥凸 (关系) (半)正定矩阵
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“原因前置词+X+的+关系”结构及其形成
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作者 焦浩 《汉语学习》 CSSCI 北大核心 2023年第1期41-49,共9页
“原因前置词+X+的+关系”结构中“关系”表原因,具有后置词性质。该结构有六种形式,文章重点描写其句法功能与分布,分析X的语义特点,对“关系”表原因的后置词用法进行了溯源。“关系”本指某种具体关系,与X所指相同,这种同一性是结构... “原因前置词+X+的+关系”结构中“关系”表原因,具有后置词性质。该结构有六种形式,文章重点描写其句法功能与分布,分析X的语义特点,对“关系”表原因的后置词用法进行了溯源。“关系”本指某种具体关系,与X所指相同,这种同一性是结构发生重新分析和“关系”语法化的诱因。X从该结构形成初期就显示出以消极性语义为主的倾向,X为NP时经常隐含消极语义。 展开更多
关键词 关系 后置词 原因 消极性语义
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Facilitators and barriers to parent-child communication in pediatric palliative care:An integrative review
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作者 Miao Zhang Huanhuan Li +1 位作者 Fei Li Yongai Zhang 《International Journal of Nursing Sciences》 CSCD 2024年第4期495-503,共9页
Objectives:This study aimed to identify facilitators and barriers to parent-child communication in pediatric palliative care,providing insights for medical professionals developing targeted interventions to enhance pa... Objectives:This study aimed to identify facilitators and barriers to parent-child communication in pediatric palliative care,providing insights for medical professionals developing targeted interventions to enhance parent-child communication and improve its effectiveness.Methods:Whittemore and Knafl’s integrative review method was employed to guide a systematic search for literature in six databases(Medline,Embase,CINAHL Complete,PsycINFO,Web of Science,and Cochrane Library).Peer-reviewer articles published in the English language from inception to December 2023.All of the identified studies were screened,extracted,and analyzed independently by two researchers.Results:Twenty-four articles were included.Thefindings of the relevant studies were analyzed using thematic analysis.Four themes were identified as facilitators:legacy-making,resilience training programs,guidance from the healthcare team,and positive communication.Seven themes were identified as barriers:denial,being unprepared and evasive,mutual protection,being overwhelmed by painful emotions and overloaded with information,incorrect views of medical professionals and parents,negative communication,and cultural context.Conclusions:Parents and professionals should avoid myths about protecting the child and encourage open communication that respects the child’s wishes.The specialized pediatric palliative care team should carefully monitor parent-child communication,determine if any obstacles exist,and design more interventions to enhance it. 展开更多
关键词 COMMUNICATION Palliative care Parent-child relationship PEDIATRICS REVIEW
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Assessment of nurses’workplace silence behaviour motives:A crosssectional study
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作者 Hanadi Mohammed Alhojairi Naglaa Abdelaziz Mahmoud Elseesy +2 位作者 Sabah Mahmoud Mahran Maram Ahmed Banakhar Fatmah Alsharif 《International Journal of Nursing Sciences》 CSCD 2024年第5期553-562,共10页
Objectives:The motives that lead to nurses’workplace silence behaviour are essential to understand,as the failure to voice their concerns and maintain silence may cause various adverse outcomes,including burnout,turn... Objectives:The motives that lead to nurses’workplace silence behaviour are essential to understand,as the failure to voice their concerns and maintain silence may cause various adverse outcomes,including burnout,turnover,job dissatisfaction,low productivity,and mental and moral distress.This study aimed to identify the level and influencing motives of the workplace silence behaviour among nurses at the National Guard Hospital in Madinah.Methods:A descriptive cross-sectional survey was conducted in January and February 2023.The participants completed a questionnaire with two parts:the sociodemographic data form and the Workplace Silence Behavior Nursing Motives Scale.Data analysis was performed by descriptive statistics and the chi-square test.Results:The overall level for all workplace silence behavior motives is moderate(3.29±0.69),with Avoidance Motives dimension receiving the highest scores(3.62±0.75)and Organization-Oriented Motives dimension receiving the lowest(3.15±0.86).Chi-square test showed that Saudi nationality(X^(2)=0.015,P=0.019)and monthly income(X^(2)=0.045,P?0.013)are factors in high-moderate levels of silence behaviour.Conclusions:The overall level of workplace silence behaviour motives was found to be moderate,nurses have higher monthly salaries and non-Saudi nationals tend to have higher levels of workplace silence behaviour motives.The study results provide a reference for nursing managers to pay attention to nurses’workplace silence behavior and take corresponding intervention measures. 展开更多
关键词 Communication barriers Nurses Workplace silence Interprofessional relations Health personnel
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A new rhombohedral phase and its 48 variants inβtitanium alloy
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作者 Xin-nan WANG Ming HAN +2 位作者 Fu-rong ZHANG Guang-ming ZHAO Zhi-shou ZHU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第9期2849-2863,共15页
A new rhombohedral phase(termed R′)in a solution-aging-treated titanium alloy(Ti-4.5Al-6.5Mo-2Cr-2Nb-1V-1Sn-1Zr,wt.%)was identified.Its accurate Bravais lattice parameters were determined by a novel unit cell reconst... A new rhombohedral phase(termed R′)in a solution-aging-treated titanium alloy(Ti-4.5Al-6.5Mo-2Cr-2Nb-1V-1Sn-1Zr,wt.%)was identified.Its accurate Bravais lattice parameters were determined by a novel unit cell reconstruction method based on conventional selected-area electron diffraction(SAED)technique.The orientation relationship between R'phase and BCC phase was revealed.The results show that the R′phase is found to have 48crystallographically equivalent variants,resulting in rather complicated SAED patterns with high-order reflections.A series of in-situ SAED patterns were taken along both low-and high-index zone axes,and all weak and strong reflections arising from the 48 variants were properly explained and directly assigned with self-consistent Miller indices,confirming the presence of the rhombohedral phase.Additionally,some criteria were also proposed for evaluating the indexed results,which together with the Bravais lattice reconstruction method shed light on the microstructure characterization of even unknown phases in other alloys. 展开更多
关键词 titanium alloy rhombohedral phase Bravais lattice reconstruction VARIANT orientation relationship
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Propositions Formalized in Chu Spaces
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作者 Shengyang Zhong 《逻辑学研究》 CSSCI 2024年第6期42-58,共17页
In the literature,there are many relational semantics of propositional logics each of which,although a satisfaction relation is defined,seems to have a“many-valued”intuition behind.More precisely,this means that a p... In the literature,there are many relational semantics of propositional logics each of which,although a satisfaction relation is defined,seems to have a“many-valued”intuition behind.More precisely,this means that a proposition can take one of more than two“truth values”at a state.In this paper,we use a kind of mathematical structures called Chu spaces to model such intuition;and we choose possibility semantics of classical logic,ortho-logic and Holliday's fundamental logic to do case studies.We formalize some informal reasonings about the intuition behind the relational semantics of these three logics,make explicit the underlying assumptions and discover some new consequences of the intuition behind these relational semantics in our setting. 展开更多
关键词 POSITIONS PROPOSITION VALUED
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Rational Synthesis of Crystalline Covalent Triazine Framework with Methylthio Pendant Arms for Efficient Mercury(Ⅱ)Adsorption
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作者 LOU Yi-xiao ZHOU Lu-lu +1 位作者 YANG Na ZHU Xiang 《分子催化(中英文)》 CAS CSCD 北大核心 2024年第4期309-316,共8页
The interest in curtailing environmental pollution issues through physical separation processes has inspired an extensive search for novel nanoporous materials with exceptional adsorption capabilities.Covalent triazin... The interest in curtailing environmental pollution issues through physical separation processes has inspired an extensive search for novel nanoporous materials with exceptional adsorption capabilities.Covalent triazine frameworks(CTFs),emerged as a class of crystalline covalent organic frameworks(COFs),have been widely examined for various separation applications,owing to their large porosity,high stability,and rich nitrogen(N)doping.The development of CTFs for efficient adsorption of mercury(Ⅱ)(Hg^(2+))is of great importance for the field,whereas it is rarely attempted,on account of limited synthetic strategies and unknown structural-property relations of conventional CTFs derived from ionothermal approaches.Herein,we report rational synthesis of a crystalline CTF with methylthio pendant arms for efficient removal of Hg^(2+)with an exceptional capacity of 751 mg·g^(-1),ranking at the top among previously-reported adsorbents.This work may open up new possibility in the synthesis of COFs for various separations. 展开更多
关键词 CTFs methylthio pendant arms mercury adsorption structural-property relationship
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From Chooz to the Ling'ao NPP:The Technology Transfer of Pressurized Water Reactor Technology from France to China
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作者 CHEN Yue LI Yunyi 《Chinese Annals of History of Science and Technology》 2024年第1期97-124,共28页
The transfer of pressurized water reactor(PWR)technology from France to China is an important event in the history of Sino-French scientific and technological relations.China has gradually achieved self-reliance in th... The transfer of pressurized water reactor(PWR)technology from France to China is an important event in the history of Sino-French scientific and technological relations.China has gradually achieved self-reliance in the field of PWR technology through the introduction and subsequent absorption of France's 900 MW reactors.Compared with the process of introducing and absorbing similar technology from the United States by France,China's experience has been more complicated.This circumstance reflects the differences in the nuclear power technology systems between the two countries.France's industrial strength and early acquisition of nuclear power technology laid a solid foundation for mastering PWR technology.On the other hand,although China established a weak foundation through the implementation of the"728 Project,"and tried hard to negotiate with France,the substantive content of the technology transfer was very limited.By way of the policy transition from"unhooking of technology and trade"to"integration of technology and trade,"China ultimately accomplished the absorption and innovation of PWR technology through the Ling'ao NPP. 展开更多
关键词 pressurized water reactor(PWR) technology transfer Sino-French relations Chooz NPP Daya Bay NPP Ling'ao NPP
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Lecturers’Efforts in Building Rapport in the English-Medium Instruction(EMI)Context:Focus on the Use of Communication Strategies
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作者 Shiyan YU Jagdish KAUR 《Chinese Journal of Applied Linguistics》 2024年第3期498-513,526,共17页
Past studies reveal the prevalence of anxiety,coupled with low motivation and disengagement among students in English-medium instruction(EMI)programs.Given the detrimental impact these negative emotions can have on le... Past studies reveal the prevalence of anxiety,coupled with low motivation and disengagement among students in English-medium instruction(EMI)programs.Given the detrimental impact these negative emotions can have on learning outcomes,it is imperative that teachers establish positive emotional rapport with their students.This study explores how experienced and highly rated EMI lecturers at a Chinese university’s overseas campus use communication strategies to build rapport with their students during interactive academic activities.It identifies the strategies used by these lecturers and examines how the strategies facilitate the teaching-learning process.The data,consisting of 10 hours of tutorials and 10 hours of supervisor-student supervision meetings,is analyzed using an adapted Conversation Analysis(CA)approach.The analysis reveals three types of communication strategies(CSs)frequently used by lecturers:back-channeling,codeswitching,and co-creation of messages.By employing these strategies,the lecturers established a strong rapport with the students,which created an encouraging and supportive learning environment.Consequently,this positive atmosphere facilitated students’learning of content knowledge through English.The findings of this study have implications for the training of lecturers who encounter difficulties in establishing rapport with multilingual students in the EMI setting. 展开更多
关键词 communication strategies English-medium instruction(EMI) rapport-building lecturer-student interaction supportive learning environment
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Inferring Genome Ancestry and Estimating Molecular Relatedness Among 187 Chinese Maize Inbred Lines 被引量:27
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作者 谢传晓 张世煌 +5 位作者 李明顺 李新海 郝转芳 白丽 张德贵 梁业红 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第8期738-748,共11页
The inference of genome ancestry and the estimation of molecular relatedness are of great importance for breeding efficiency and association studies. Seventy SSR loci, evenly distributed in 10 chromosomes, were assaye... The inference of genome ancestry and the estimation of molecular relatedness are of great importance for breeding efficiency and association studies. Seventy SSR loci, evenly distributed in 10 chromosomes, were assayed for polymorphism among 187 commonly used maize (Zea mays L.) inbreds which represent the genetic diversity in China. The identified 290 alleles served as raw data for estimating population structure using the coalescent linked loci, based on the ADMIXTURE model. Population number, K, has been inferred to be between five and seven. Specifying five subpopulations (K = 5) led to a distinct decrease and specifying K to be greater than six resulted in only minimal increases in the likelihood value. Therefore, population number, K, has been inferred into six subpopulations, which are PA, BSSS (includes Reid), PB, Lan (Lancaster Sure Crop), LRC (Luda Reb Cob, a Chinese landrace, and its derivatives), and SPT (Si-ping-tou, a Chinese landrace and its derivatives). The Kullback-Leibler distance of pairwise subpopulation was also inferred as n × p (187 ×6) Q matrices, which gave a detailed percentage of genetic composition of six subpopulations and molecular relatedness of each line. The genome-wide linkage disequilibrium (LD) indicated that the asso- ciation studies in QTLs and/or candidate genes might avoid nonfunctional and spurious associations, as most of the LD blocks were broken among diverse germplasm. The defined population structure has given us a clear genetic structure of these lines for breeding practice and established a good basis for association analysis. 展开更多
关键词 MAIZE genetic diversity relatedness linkage disequilibrium association analysis
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Determination of local constitutive behavior and simulation on tensile test of 2219-T87 aluminum alloy GTAW joints 被引量:6
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作者 李艳军 李权 +5 位作者 吴爱萍 麻宁绪 王国庆 Hidekazu MURAKAWA 鄢东洋 吴会强 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第9期3072-3079,共8页
The local and global mechanical responses of gas tungsten arc welds(GTAW) of a 2219-T87 aluminum alloy were investigated with experiment and numerical simulation.Digital image correlation(DIC) was used to access t... The local and global mechanical responses of gas tungsten arc welds(GTAW) of a 2219-T87 aluminum alloy were investigated with experiment and numerical simulation.Digital image correlation(DIC) was used to access the local strain fields in transversely loaded welds and to determine the local stress-strain curves of various regions in the joint.The results show that the DIC method is efficient to acquire the local stress-strain curves but the curves of harder regions are incomplete because the stress and strain ranges are limited by the weakest region.With appropriate extrapolation,the complete local stress-strain curves were acquired and proved to be effective to predict the tensile behavior of the welded joint.During the tensile process,the fracture initiates from the weld toes owing to their plastic strain concentrations and then propagates along the fusion line,finally propagates into the partially melted zone(PMZ). 展开更多
关键词 aluminum alloy tensile behavior digital image correlation constitutive behavior welded joint
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Vegetation-Climate Relationship and Its Application in the Division of Vegetation Zone in China 被引量:39
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作者 方精云 宋永昌 +1 位作者 刘鸿雁 朴世龙 《Acta Botanica Sinica》 CSCD 2002年第9期1105-1122,共18页
Distribution of vegetation is closely coupled with climate; the climate controls distribution of vegetation and the vegetation type reflects regional climates. To reveal vegetation_climate relationships is the foundat... Distribution of vegetation is closely coupled with climate; the climate controls distribution of vegetation and the vegetation type reflects regional climates. To reveal vegetation_climate relationships is the foundation for understanding the vegetation distribution and theoretically serving vegetation regionalization. Vegetation regionalization is a theoretical integration of vegetation studies and provides a base for physiogeographical regionalization as well as agriculture and forestry regionalization. Based on a brief historical overview on studies of vegetation_climate relationships and vegetation regionalization conducted in China, we review the principles, bases and major schemes of previous vegetation regionalization and discuss on several contentious boundaries of vegetation zones in the present paper. We proposed that, under the circumstances that the primary vegetation has been destroyed in most parts of China, the division of vegetation zones/regions should be based on the distribution of primary and its secondary vegetation types and climatic indices that delimit distribution of the vegetation types. This not only reveals the closed relationship between vegetation and climate, but also is feasible practically. Although there still are divergence of views on the name and their boundaries of the several vegetation zones, it is commonly accepted that there are eight major vegetation regions in China, i.e. cold temperate needleleaf forest region, temperate needleleaf and broadleaf mixed forest region, warm temperate deciduous broadleaf forest region, subtropical evergreen broadleaf forest region, tropical monsoon forest and rain forest region, temperate steppe region, temperate desert region, and Qinghai_Xizang (Tibetan) Plateau high_cold vegetation region. Analyzing characteristics of vegetation and climate of major vegetation boundaries, we suggested that: 1) Qinling Mountain_Huaihe River line is an important arid/humid climatic, but not a thermal climatic boundary, and thus can not also be regarded as the northern limit of the subtropical vegetation zone; 2) the northern limit of subtropical vegetation zone in China is along the northern coast of the Yangtze River, from Hangzhou Bay, via Taihu Lake, Xuancheng and Tongling in Anhui Province, through by southern slope of the Dabie Mountains, to Wuhan and its west, coinciding with a warmth index ( WI ) value of 130-140 ℃·month; 3) the tropical region is limited in a very small area in southeastern Hainan Island and southern edge of Taiwan Island; and 4) considering a significant difference in climates between the southern and northern parts of the warm temperate zone, we suggested that the warm temperate zone in China is divided into two vegetation regions, deciduous broadleaf woodland region and deciduous and evergreen broadleaf mixed forest region, the Qinling Mountain_Huaihe River line being as their boundary. We also claimed that the zonal vegetation in North China is deciduous broadleaf woodland. Finally, we emphasized the importance of dynamic vegetation regionalization linked to climate changes. 展开更多
关键词 China dynamic vegetation regionalization arid/humid climate northern limit of subtropical zone Qinling Mountain_Huaihe River line thermal climate vegetation_climate relationship vegetation regionalization vegetation zone
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Water Relations on Alhagi sparsifolia in the Southern Fringe of Taklamakan Desert 被引量:23
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作者 李向义 张希明 +5 位作者 曾凡江 Andrea FOETZKI Frank M .THOMAS 李小明 Michael RUNGE 何兴元 《Acta Botanica Sinica》 CSCD 2002年第10期1219-1224,共6页
Water relations of Alhagi sparsifolia Shap. at the transition zone between oases and sandy desert were studied in the southern fringe of Taklamakan Desert. Results showed that A. sparsifolia maintained the positive tu... Water relations of Alhagi sparsifolia Shap. at the transition zone between oases and sandy desert were studied in the southern fringe of Taklamakan Desert. Results showed that A. sparsifolia maintained the positive turgor during the summer. The steady high predawn water potential (psi(P)) indicated A. sparsifolia had sufficient hydration and water supply in growing season. In July, water deficit caused by drought stress had no effect on the transpiration of A. sparsifolia. Therefore, drought stress is not a main factor affecting the survival of plants. The physiological adaptation to drought of A. sparsifolia was shown mainly at the leaf level by significant difference (DeltaII) and relative water content (RWC) between the osmotic pressure at full turgor and at turgor loss, by occurring of osmotic adjustment, by high percentage of dry mass-related water content ( WCsat), by RWC at turgor loss point ( RWCp) in stable level and low RWC of the saturated symplast (RWCsym). However, the morphological features of transpiring surface reduction and deep root system seem to be the main way for the plant to adapt to the extreme drought environment. Result also suggests that one time of irregular irrigation in summer will not be helpful to recover water status of A. sparsifolia in location where the water table is very low. 展开更多
关键词 Alhagi sparsifolia water relation drought stress water potential PV parameters irrigation effect
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AFLP Variation Analysis on the Germplasm Resources of Leymus chinensis 被引量:10
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作者 刘杰 朱至清 +2 位作者 刘公社 齐冬梅 李芳芳 《Acta Botanica Sinica》 CSCD 2002年第7期845-851,共7页
The fingerprints of 27 Leymus chinensis (Trin.) Tzvel accessions from different regions in China were generated and their genomic DNA variations were assayed via amplified fragment length polymorphism (AFLP). A to... The fingerprints of 27 Leymus chinensis (Trin.) Tzvel accessions from different regions in China were generated and their genomic DNA variations were assayed via amplified fragment length polymorphism (AFLP). A total of 537 DNA fragments were amplified ranging from 75-530 bp using 8 AFLP primer combinations, among which 89 (16.6%) were monomorphic and 329 (61.3%) were polymorphic. The average number of DNA band produced by each primer combination was 66.13 and the total polymorphic rate was 78.84%. PICs (polymorphic information contents) scores for AFLP ranged from 0.0-0.5 and the mean PIC was 0.216. PIC scores were maximum (0.5) for 8.5% of the AFLP markers. All the results revealed that there was rich polymorphism in genomic DNA of L. chinensis . A DNA molecular dendrogram was established for 27 L. chinensis genotypes based on genetic variation and UPGMA cluster analysis of 537 AFLP markers amplified by 8 primer combination, suggesting that the genetic variation with high frequency showed close correlation with their ecotopes and geographical distributions. Twenty_seven L. chinensis genotypes could be divided into four groups. Among them the lower genetic relationship was shown. The reason of high genetic variation frequency in L. chinensis species and formation of varieties was discussed. 展开更多
关键词 Leymus chinensis AFLP genetic relationship
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Use of the pilodyn for assessing wood properties in standing trees of Eucalyptus clones 被引量:3
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作者 吴世军 徐建民 +4 位作者 李光友 RISTO Vuokko 陆钊华 李宝琦 王伟 《Journal of Forestry Research》 SCIE CAS CSCD 2010年第1期68-72,I0003,共6页
The effectiveness of pilodyn was tested in evaluating wood basic density, outer wood density, heartwood density, and modulus of elasticity (MoE) at 22 four-year-old eucalyptus clones in Guangxi, China. Results indic... The effectiveness of pilodyn was tested in evaluating wood basic density, outer wood density, heartwood density, and modulus of elasticity (MoE) at 22 four-year-old eucalyptus clones in Guangxi, China. Results indicated that the mean value ranged from 9.44 to 15.41 mm for Pilodyn penetration, 0.3514 to 0.4913 g.cm^-3 for wood basic density, and 3.94 to 7.53 Giga Pascal (GPa) for MoE, respectively. There were significant differences (1% level) in pilodyn penetration between different treatments, different directions and among the clones. Generally strongly negative correlations were found between pilodyn penetration and wood properties, and the coefficients ranged from -0,433 to -0,755. Our results, together with other studies, suggest that the use of pilodyn for assessing wood density and MoE was confirmed as a possibility. 展开更多
关键词 CORRELATION EUCALYPTUS modulus of elasticity PILODYN wood density
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The Application of Pearson Correlational Analysis Method in Air Quality Analysis of Beijing-Tianjin-Hebei Region 被引量:15
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作者 杨宁 冀德刚 李双金 《Agricultural Science & Technology》 CAS 2015年第3期590-592,共3页
Based on the analysis of monitoring data on six pollution indexes of SO2, NO2, CO, O3, PM10 and PM2.5 from 53 monitoring points in 7 cities, including Beijing, Tianjin, Shijiazhuang, etc., from April 8 of 2014 to July... Based on the analysis of monitoring data on six pollution indexes of SO2, NO2, CO, O3, PM10 and PM2.5 from 53 monitoring points in 7 cities, including Beijing, Tianjin, Shijiazhuang, etc., from April 8 of 2014 to July 23 of 2014, this article adopted Pearson correlation coefficient method to determine the relevance among each pollutant of these cities with the help of SPSS. The results showed that such three leading indexes as SO2, PM10 and PM2.5 had strong correlation in Beijing, Tianjin and main cities of Hebei. Finally, some suggestions and preventive measures for the cooperative governance of air pollution in Beijing-Tianjin-Hebei Region were put forward, hoping this can help them. 展开更多
关键词 Pearson Correlation coefficient Linear interpolation Monitoring indicators Air quality
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Cardinal Numbers of Fuzzy Sets 被引量:8
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作者 李洪兴 罗承忠 +1 位作者 汪培庄 袁学海 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第3期101-107,共7页
Up to now, the study on the cardinal number of fuzzy sets has advanced at on pace since it is very hard to give it an appropriate definition. Althrough for it in [1], it is with some harsh terms and is not reasonable ... Up to now, the study on the cardinal number of fuzzy sets has advanced at on pace since it is very hard to give it an appropriate definition. Althrough for it in [1], it is with some harsh terms and is not reasonable as we point out in this paper. In the paper, we give a general definition of fuzzy cardinal numbers. Based on this definition, we not only obtain a large part of results with re spect to cardinal numbers, but also give a few of new properties of fuzzy cardinal numbers. 展开更多
关键词 Fuzzy relations Fuzzy mappings the cardinal numbers of fuzzy sets
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Infrageneric and Sectional Relationships in the Genus Rhododendron (Ericaceae) Inferred from ITS Sequence Data 被引量:11
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作者 高连明 李德铢 +1 位作者 张长芹 杨俊波 《Acta Botanica Sinica》 CSCD 2002年第11期1351-1356,共6页
The internal transcribed spacer (ITS) regions of nuclear ribosomal DNA (including 5.8S rRNA) of 15 Rhododendron, species, representing most sections of the genus, one Ledum species and Cassiope fastigiata were sequenc... The internal transcribed spacer (ITS) regions of nuclear ribosomal DNA (including 5.8S rRNA) of 15 Rhododendron, species, representing most sections of the genus, one Ledum species and Cassiope fastigiata were sequenced. Together with the ITS sequences of 13 selected Rhododendron species and Bejaria racemosa downloaded from GenBank, we explored the infrageneric and sectional relationships of this important North Temperate genus by employing maximum-parsimony analysis using PAUP software. C. fastigiata and B. racemosa were designated as outgroups. The ITS-based tree inferred that: (1) Rhododendron was a well-supported monophyletic group, while subg. Therorhodion was basal to the rest of the genus; (2) Ledum was a member of Rhododendron, and its close relationship with the lepidote rhododendron was confirmed; (3) the lepidote rhododendron plus Ledum formed a strongly-supported monophyletic clade which was sister to the rest of the elepidote rhododendron; (4) the elepidote rhododendron formed a weakly-supported clade within which the monophyly of subg. Hynwrianthes and subg. Tsutsusi were strongly supported, while subg. Pentanthera and subg. Azaleastrum were polyphyletic; and (5) the monophyly of sect. Choniastnini, (subg. Azaleastrum) was strongly-supported, while subg. Tsutsusi could be sister to a weakly-supported clade composed of two sampled species of sect. Azaleastrum (subg. Azaleastrum) together with R. sentibarbatum, of subg. Mumeazalea. 展开更多
关键词 RHODODENDRON internal transcribed spacer (ITS) PHYLOGENY infrageneric relationships
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