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论物上利益及其基础上的物权法体系
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作者 车清谨 杨承亮 《菏泽师专学报》 2004年第1期77-82,共6页
以物上利益为核心的物权法体系是物上利益———基本性物权———辅助性物权———综合性物权———包含有物权的综合性权利所组成的网状结构 ,它以物上利益为核心 ,以存在于现实生活中的广泛多样的各种综合性权利为最终边界 ,是一条完... 以物上利益为核心的物权法体系是物上利益———基本性物权———辅助性物权———综合性物权———包含有物权的综合性权利所组成的网状结构 ,它以物上利益为核心 ,以存在于现实生活中的广泛多样的各种综合性权利为最终边界 ,是一条完整的从抽象到具体 ,从理论到实践的联通。基本性物权是物权法体系中直接反映物上利益的物权种类 ,物上利益在法律中物化的第一步就表现为基本性物权 ,整个物权法体系就是架构在基本性物权这几根支柱之上的 ,考察物权与物上利益的联系程度 ,基本性物权应该包括 :使用权、价值权。 展开更多
关键词 上利益 权法体系 本性
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从自然法理念的转变看环境法功能实现的思想基础 被引量:1
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作者 刘卫先 《内蒙古农业大学学报(社会科学版)》 2008年第1期270-273,共4页
自然法在其两千多年的历史中一直被接受它人们遵从为权威与理性的化身,作为一种巨大的无形力量指导着人们的行为。自然法的本质理念从物本性到神本性,再到人本性。人本性的宣扬是环境危机的思想根源,现代社会要从根本上促进环境法功能... 自然法在其两千多年的历史中一直被接受它人们遵从为权威与理性的化身,作为一种巨大的无形力量指导着人们的行为。自然法的本质理念从物本性到神本性,再到人本性。人本性的宣扬是环境危机的思想根源,现代社会要从根本上促进环境法功能的实现,必须用物本性与神本性的"否定之否定回复"思想去指导人们的行为。 展开更多
关键词 自然法 理念 物本性 本性 本性
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Intraclonal Resource Sharing and Functional Specialization of Ramets in Response to Resource Heterogeneity in Three Stoloniferous Herbs 被引量:8
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作者 于飞海 董鸣 张称意 《Acta Botanica Sinica》 CSCD 2002年第4期468-473,共6页
Environments with reciprocal patchiness of resources, in which the availability of two resources such as light and soil nutrients are patchily distributed in horizontal space and negatively correlated in each patch, a... Environments with reciprocal patchiness of resources, in which the availability of two resources such as light and soil nutrients are patchily distributed in horizontal space and negatively correlated in each patch, are common in many ecosystems. The strategies by which clonal plants adapt to this type of heterogeneous environment were examined in three stoloniferous herbs,Potentilla reptans L. var. sericophylla Franch., P. anserina L. and Halerpestes ruthenica (Jacq.) Qvcz., commonly inhabiting forest understories, grasslands and low saline meadows, respectively. As pairs of connected ramets were subjected to reciprocal patchiness of light and nutrients, stolon connection between the two ramets significantly enhanced biomass of both ramet growing in low light intensity but high soil nutrient condition (LH ramet) and ramet growing in high light intensity but low soil nutrient condition (HL ramet) as well as whole ramet pairs (consisting of LH ramets and HL ramets). Additionally, stolon connection greatly increased root/shoot ratio of LH ramet while significantly decreased that of HL ramet. The results indicate that a reciprocal transportation of resources between interconnected ramets and a functional specialization of ramets in uptake of abundant resources occurred. By resource sharing and functional specialization, clonal plants can efficiently acquire locally abundant resources and buffer the stress caused by reciprocal patchiness of resources. 展开更多
关键词 Halerpestes ruthenica Potentilla anserina P. reptans var. sericophylla functional specialization light intensity nutrient content reciprocal patchiness of resources resource sharing
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Research on Stoichiometry of Early-spring Herbs Functional Group in the Subtropical Artificial Wetland
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作者 牛晓音 常杰 +1 位作者 葛滢 郑家文 《Agricultural Science & Technology》 CAS 2011年第8期1182-1185,1190,共5页
[Objective]The aim was to carry out stoichiometry on the early-spring herbs functional group in subtropical artificial wetland.[Method]UV-Vis spectrophotometer was used for the determination of nitrate-nitrogen,ammoni... [Objective]The aim was to carry out stoichiometry on the early-spring herbs functional group in subtropical artificial wetland.[Method]UV-Vis spectrophotometer was used for the determination of nitrate-nitrogen,ammonium nitrogen and phosphorus concentrations.Potassium persulfate absorptiometry was used for the measurement of total N content,while the flame photometer was used to detect the potassium and sodium concentration in plants.All the nutrient determination of plant samples were repeated for four times.[Result]The four nutrient concentrations in almost all samples were in the normal range of natural plant nutrition concentrations;in early-spring herbs functional groups,different species showed diversity on the nutrient concentrations;plant height had no significant effect on the nutrient concentrations in plants;the nutrient concentrations of non-grass group plants were higher than that of grass group plants;the nutrient concentrations of the annual herb were higher than that of perennial herbs.[Conclusion]The study had provided basis for the understanding of the effects of changes in nutritional conditions on species diversity,community structure and succession of the system. 展开更多
关键词 Early-spring herbs Functional group BIODIVERSITY Element STOICHIOMETRY
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Genetic Relationships Among Soluble Carbohydrates, Anthocyanins and Growth Characteristics in Leymus (Gramineae) Detected with Molecular Markers 被引量:3
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作者 胡赞民 Steven R. LARSON +1 位作者 Thomas A. JONES Richard R-C. WANG 《Acta Botanica Sinica》 CSCD 2002年第10期1173-1181,共9页
Low-temperature soluble carbohydrate accumulations are commonly associated with anthocyanin coloration, attenuated growth and cold adaptation of cool-season grasses. The vrn-1 gene has potent effects on vernalization ... Low-temperature soluble carbohydrate accumulations are commonly associated with anthocyanin coloration, attenuated growth and cold adaptation of cool-season grasses. The vrn-1 gene has potent effects on vernalization requirement, growth, and soluble carbohydrate accumulations of the winter-annual Triticeae species. Two hundred and four unmapped AFLP markers and genome-specific DNA markers genetically linked to the vrn-1 gene were used to detect QTL controlling soluble carbohydrate accumulations, anthocyanin coloration and growth characteristics in a segregating population derived from open pollinated Leymus cinereus x L. triticoides hybrids. These perennial Triticeae grasses are distinguished by adaptation and growth habit. As expected, positive trait correlations and pleiotropic gene effects were detected for soluble carbohydrate accumulations and anthocyanin coloration. Likewise, positive trait correlations and pleiotropic gene effects were detected for tillering, leaf development, leaf growth, regrowth and rhizome spread. However, soluble carbohydrate accumulations were not associated with attenuated growth. In fact, several DNA marker alleles, including one near vrn-Ns1, had positive effects on soluble leaf carbohydrate concentrations and low temperature growth. The corresponding DNA marker near vrn-Ns1 had more specific effects on tillering. We speculate that vrn-1 exerts quantitative effects on low-temperature soluble leaf carbohydrate accumulations and growth habit of the perennial Leymus. However, a number of other DNA markers displayed highly significant effects on soluble carbohydrate accumulations and various growth characteristics. Findings indicate that anthocyanin coloration may be a useful phenotypic marker for soluble carbohydrate accumulation. Although variation for soluble carbohydrates was not associated with attenuated growth in this population, this trait was under genetic control. 展开更多
关键词 LEYMUS molecular markers genetic relationship
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Study on Biological Characters of Asparagus macowanii Baker. 被引量:1
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作者 刘方农 彭世逞 刘联仁 《Agricultural Science & Technology》 CAS 2012年第11期2351-2354,共4页
Asparagus macowanfi Baker, is a climbing herbaceous foliage species in genus Asparagus of Liliaceae, This paper summarized its multiple uses, morphologi- cal characteristics, biological habit, reproduction methods, ma... Asparagus macowanfi Baker, is a climbing herbaceous foliage species in genus Asparagus of Liliaceae, This paper summarized its multiple uses, morphologi- cal characteristics, biological habit, reproduction methods, management after cultiva- tion, prevention and control of pests and disease, as well as harvest and grading, with the objective to provide references for the exploitation and utilization of As- paragus macowanii Baker. 展开更多
关键词 Asparagus macowanii Baker Biological Characters Multiple uses
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Chemical constituents and antioxidant activities of waste liquid extract from Apostichopus japonicus Selenka processing 被引量:1
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作者 李超峰 李宪璀 +2 位作者 李红 郭书举 朱校斌 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第4期850-859,共10页
Apostichopus japonicus Selenka is an ideal tonic food that is used traditionally in many Asian countries, and it contains many bioactive substances, such as antioxidant, antimicrobial, and anticancer materials. To con... Apostichopus japonicus Selenka is an ideal tonic food that is used traditionally in many Asian countries, and it contains many bioactive substances, such as antioxidant, antimicrobial, and anticancer materials. To convert waste liquid generated during production into a useful resource, extract from waste liquid was isolated by column chromatography and studied by the pyrogallol autoxidation and 1,10-phenanthroline-Fe^2+ oxidation methods. Results show that the extract scavenged about 91% of the superoxide anion radical at a concentration of 1.4 mg/mL and 24% of the hydroxyl radical at 3.3 mg/mL. Four compounds were isolated and identified from the extract: 2,4-dihydroxy-5-methyl-1,3-azine; 2,4-dihydroxy- 1,3-diazine; 3-O-β-D-quinovopranosyl-(1→2)-4-O-sodium sulfate-β-D-xylopranosyl]-holosta-9(11)-ene313,12β,17α-triol; and 24-ethyl-5α-cholesta-7-ene-3β-O-β-D-xylopyranoside. All of these compounds are known in A. japonicus, and were found in the waste liquid for the first time. 展开更多
关键词 waste liquid EXTRACTION antioxidant activity chemical constituents
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Woody Species Diversity and Forest Structure from Lowland to Montane Forest in Hyrcanian Forest Ecoregion 被引量:2
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作者 Seyed Mohammad JAFARI Shahin ZARRE Seyed Kazem ALAVIPANAH 《Journal of Mountain Science》 SCIE CSCD 2013年第4期609-620,共12页
Alborz Mountains host Caspian Hyrcanian forest ecoregion along the northern slopes and forest steppe ecoregion in highlands. Hyrcanian forest covers the southeastern part of Caucasus biodiversity hotspot and is of gre... Alborz Mountains host Caspian Hyrcanian forest ecoregion along the northern slopes and forest steppe ecoregion in highlands. Hyrcanian forest covers the southeastern part of Caucasus biodiversity hotspot and is of great biogeographic importance. Altitudinal pattern and correlation between woody species biodiversity (DIV), forest structure ((stem density (DEN), mean basal area (MBA) and mean height class (MHC)) and disturbance (DIS) were explored along 2,4oo m altitudinal gradient in Hyrcanian relict forest, Central Alborz Mountains. Vegetation changes from lowland forest (LoF) to mid- altitude forest (MiF) and montane forest (MoF) in this area. The altitudinal gradient was divided into twelve 200 m elevational belts. Point centered quarter method (PCQM) with 96 sampling points and 83 vegetation samples by plot method (PM) were used to record field data. Shannon-Wiener index and Pearson coefficient were used for diversity and correlation analysis. The results showed that DEN decreased linearly, MBA and MHC showed relatively hump shaped and DIS showed a reverse hump shaped pattern of change along altitudinal gradient. Woody species diversity decreased non-steadily from LoF to MoF. Transitional vegetations of Carpinus-Fagus and Fagus-Quercus represented higher diversity of woody taxa compared to adjacent homogenous communities. Significant correlation was observed between altitude and all parameters: DEN with MBA, DIS and DIV; MBA with DIS; MHC with DIS along with DIV; and DIS with DIV at the study area scale. Surprisingly,correlation between studied parameters differed within each vegetation type. Altitude probably acts as a proxy for human and environmental driving forces in this area. Stability of warm and wet condition, season length, soil depth along with forest accessibility probably influences the altitudinal pattern of the studied parameters. Disturbance affects forest structure and consequently diversity; especially in lowlands. The obtained results recommend using both forest biodiversity and mensuration data in management process of forest ecosystems. 展开更多
关键词 Alborz Mountains BIODIVERSITY ForestMensuration Hyrcanian forest DISTURBANCE
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Logistics Cost Management Models and Their Usability for Purchasing 被引量:1
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作者 Daniel Ellstrom Jakob Rehme Maria Bjorklund Hakan Aronsson 《Journal of Modern Accounting and Auditing》 2012年第7期1066-1073,共8页
In many compames, cost management models are abandoned due to their complexity and because of this, the academic literature has experienced a downturn in publications regarding cost management. This paper deepens the ... In many compames, cost management models are abandoned due to their complexity and because of this, the academic literature has experienced a downturn in publications regarding cost management. This paper deepens the understanding regarding the practical usability of cost management models for purchasing decisions, and provides a framework for determining a desired complexity of cost management in different purchasing environments. The complexity is defined along three dimensions identified in literature and the different purchasing environments stem from an adaptation of Kraljic's (1983) matrix. 展开更多
关键词 cost management supply chain ACCOUNTING PURCHASING Kraljic's matrix
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Physical Properties and Electrochemical Performance of Solid K_2FeO_4 Samples Prepared by Ex-situ and in-situ Electrochemical Methods 被引量:2
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作者 徐志花 王建明 +1 位作者 邵海波 张鉴清 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第1期39-43,共5页
K2FeO4 powders were synthesized by the ex-situ and in-situ electrochemical methods, respectively, and characterized by infrared spectrum (IR), scanning electron microscopy (SEM), X-ray powder diffraction (XRD) a... K2FeO4 powders were synthesized by the ex-situ and in-situ electrochemical methods, respectively, and characterized by infrared spectrum (IR), scanning electron microscopy (SEM), X-ray powder diffraction (XRD) and BET. Their electrochemical performances were investigated by means of galvanostatic discharge and electrochemi-cal impedance spectroscopy (EIS). The results of physical characterization showed that the two samples have simi-lar structural features, but their surface morphologies and oriented growth of the crystals are different, which results in smaller specific surface area and lower solubility of the ex-situ electrosynthesized K2FeO4 sample. The results of discharge experiments indicated that the ex-situ electrosythesized K2FeO4 electrode has much larger discharge ca-pacity and lower electrode polarization than the in-situ electrosynthesized K2FeO4 electrode. It was found from the results of EIS that lower electrochemical polarization might be responsible for the improvement on the discharge performance of the ex-situ electrosynthesized K2FeO4 electrode. 展开更多
关键词 K2FeO4 ELECTROSYNTHESIS discharge performance electrochemical impedance spectroscopy (EIS)
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Net Primary Productivity and Species Diversity of Herbaceous Vegetation in Banj-oak (Quercus leucotri-chophora A.Camus) Forest in Kumaun Himalaya,India 被引量:1
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作者 Mukesh JOSHI Y.S.RAWAT 《Journal of Mountain Science》 SCIE CSCD 2011年第6期787-793,共7页
Net primary productivity and species diversity of herbaceous vegetation of banj-oak (Quercus leucotrichophora A. Camus) forest in Kumaun Himalaya, India were analyzed. Across different growth forms (tall forbs, sho... Net primary productivity and species diversity of herbaceous vegetation of banj-oak (Quercus leucotrichophora A. Camus) forest in Kumaun Himalaya, India were analyzed. Across different growth forms (tall forbs, short forbs, cushion and spreading forbs, grasses), short forbs were most dominant component during rainy season (1VI=152) and winter season (IVI=167) and grasses during the winter season (IVI=148). Maximum above-ground production occurred during rainy season (132.5 g m-2) and minimum during winter season (2.8 g m-~). Below-ground production was maximum (85.9 g m-x) during winter season and minimum (14.9 g m-x) during summer season. Annual net shoot production was 15o g m-~ and below-ground production was 138 g m-~. Of the total input 61% was channeled to above- ground parts and 39% to below-ground parts. 展开更多
关键词 BIOMASS Diversity Net-primaryproductivity
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Life Strategy Traits of the Liana Sericostachys scandens Spreading in the Montane Forests in the Kahuzi-Biega National Park (DR Congo)
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作者 Masumbuko Ndabaga Céphas Herpigny Basile +3 位作者 Barbier Nicolas Habiyaremye Muhashy Franois Lejoly Jean Meerts Pierre 《Journal of Mountain Science》 SCIE CSCD 2012年第5期665-675,共11页
Sericostaehys seandens is a monocarpic and heliophilous liana, native in tropical African forests. In the montane forests of the Kahuzi-Biega National Park (KBNP) (East of DR Congo), it has been expanding very str... Sericostaehys seandens is a monocarpic and heliophilous liana, native in tropical African forests. In the montane forests of the Kahuzi-Biega National Park (KBNP) (East of DR Congo), it has been expanding very strongly for a decade, and is currently considered as having negative impacts on biodiversity conservation. In this paper, we test if S. scandens differs from three co-occurring, native, non spreading lianas (Gouania longispicata, Tacazzea apiculata and Adenia bequaertii) for functional traits which might influence plant expansion. For leaf traits (SLA, dry matter content, nitrogen concentration), S. scandens did not show extreme values compared to those of the three other lianas. In contrast, S. scandens had much higher biomass allocation to sexual reproduction. It also differs from the three other lianas for its reproductive strategy that combines both vegetative propagation and sexual reproduct/on, and propagule dispersal by wind. Moreover, S. scandens has larger leaves and a greater number of lateral branches per unit stem length. It is argued that the particular combination of functional traits exhibited by S.scandens may in part explain its propensity to behave as an opportunistic weed in the disturbed areas in the montane forests of Kahuzi-Biega. 展开更多
关键词 Life strategy Sericostachys seandens montane forest Kahuzi-Biega National Park functional traits Native expanding species.
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撩开发明创造的面纱——发明创造原理与方法漫谈(连载)
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作者 赵一飞 《发明与革新》 2002年第3期6-7,共2页
关键词 发明创造 客观规律 本性 概念
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Isotopic and Chemical Characteristics of Lagoon Waters in Niigata Prefecture, Japan
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作者 Adilijiang Tiemuer Naoki Kano +1 位作者 Hiroshi Imaizumi Naoki Watanabe 《Journal of Environmental Science and Engineering(A)》 2015年第3期131-136,共6页
In order to investigate the isotopic and chemical characteristics of lagoon waters in Niigata Prefecture in recent years, oxygen and hydrogen stable isotope ratios (i.e., 8180 and 6D), the concentrations of DOC (di... In order to investigate the isotopic and chemical characteristics of lagoon waters in Niigata Prefecture in recent years, oxygen and hydrogen stable isotope ratios (i.e., 8180 and 6D), the concentrations of DOC (dissolved organic carbon), DO (dissolved oxygen) and pH, etc. in water samples of Sakata and Toyanogata were measured. Samples were generally taken monthly at the fixed sampling points from these lagoons. Consequently, the following matters have been mainly clarified: (1) ~D value of water samples in Sakata was generally larger than that in Toyanogata similarly to the case of ~180, though remarkable large difference among samples was not found; (2) the pH value of lagoon water samples is almost 6.5-8.5 (which is generally larger than that of river water), and pH at the spot of SI (downstream point of Lower Lagoon (Shitakata)) is remarkably high (9.0-9.5); (3) Lagoon water has the chemical characteristics contrasting to groundwater with a focus on river water from the viewpoint of pH (acidity or alkalinity) and DO. These matters can be closely related to the biological activity such as photosynthesis due to aquatic plant and phytoplankton and the activity of Crustacea plankton etc. in lagoon. 展开更多
关键词 Lagoon water oxygen and hydrogen stable isotopic ratio DOC DO Niigata Prefecture.
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The Alpine Seed Conservation and Research Network–a new initiative to conserve valuable plant species in the European Alps
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作者 MULLER Jonas V BERG Christian +11 位作者 DETRAZ-MEROZ Jacqueline ERSCHBAMER Brigitta FORT Noemie LAMBELET-HAUETER Catherine MARGREITER Vera MOMBRIAL Florian MONDONI Andrea PAGITZ Konrad PORRO Francesco ROSSI Graziano SCHWAGER Patrick BREMAN Elinor 《Journal of Mountain Science》 SCIE CSCD 2017年第4期806-810,共5页
Safeguarding plants as seeds in ex situ collections is a cost effective element in an integrated plant conservation approach. The European Alps are a regional centre of plant diversity. Six institutions have establish... Safeguarding plants as seeds in ex situ collections is a cost effective element in an integrated plant conservation approach. The European Alps are a regional centre of plant diversity. Six institutions have established a regional network covering the European Alps which will conserve at least 500 priority plant species and which will improve the conservation status of plant species in grassland communities in the subalpine, alpine and nival altitudinal belts. Targeted research will expand the knowledge of the ecology of target speeies. Public engagement activities will raise the awareness for the importance of specific conservation actions in the European Alps. 展开更多
关键词 ALPINE Seed banks Ex situ conservation PLANTS EUROPE Natural grasslands Endemic species
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Deformation characteristics and constitutive model of seafloor massive sulfides
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作者 胡建华 刘少军 +1 位作者 张瑞强 胡琼 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第9期1986-1991,共6页
Deformation characteristics and constitutive model of seafloor massive sulfide(SMS)were selected as the research object.Uniaxial/triaxial compression test were carried out on the mineral samples,and the deformation ch... Deformation characteristics and constitutive model of seafloor massive sulfide(SMS)were selected as the research object.Uniaxial/triaxial compression test were carried out on the mineral samples,and the deformation characteristics of specimens under various conditions were studied.According to characteristics of the mineral,a new three stages constitutive equation was proposed.The conclusions are as follows:The axial strain,peak strain and maximum strength of seafloor massive sulfide increase with the confining pressure.The elastic modulus of the metal sulfide samples is decreased sharply with the increase of confining pressure.According to characteristics of seafloor massive sulfide,the constitutive equation is divided into three parts,the comparison between theoretical curves and experimental data shows that both of them are in good agreement,which also proves the correctness of the constitutive equation for uniaxial compression. 展开更多
关键词 seafloor massive sulfide constitutive model failure characteristics DAMAGE uniaxial strain triaxial strain
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Changes in microbial community composition in the leaf litter of successional communities after volcanic eruptions of Mount Usu, northern Japan 被引量:2
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作者 Michiru OTAKI Fumiko TAKEUCHI Shiro TSUYUZAKI 《Journal of Mountain Science》 SCIE CSCD 2016年第9期1652-1662,共11页
Changes in the fungal and bacterial biomass and community structure in litter after the volcanic eruptions of Mount Usu, northern Japan were investigated using a chronosequence approach, which is widely used for analy... Changes in the fungal and bacterial biomass and community structure in litter after the volcanic eruptions of Mount Usu, northern Japan were investigated using a chronosequence approach, which is widely used for analyzing vegetation succession. The vegetation changed from bare ground (10 years after the eruptions) with little plant cover and poor soil to monotonic grassland dominated by Polygonum sachalinense with undeveloped soil (33 years) and then to deciduous broad-leaved forest dominated by Populus maximowiczii with diverse species composition and well-developed soil (100 years). At three chronosequential sites, we evaluated the compositions of phospholipid fatty acids (PLFAs), carbon (C) and nitrogen (N) contents and the isotope ratios of C (δ13C) and N (δ15N) in the litter of two dominant species, Polygonum sachalinense and Populus maximowiezii. The C/N ratio, δ13C and δ15N in the litter of these two species were higher in the forest than that in the bare ground and grassland. The PLFAs gradually increased from the bare ground to the forest, showing that microbial biomass increased with the development of the soil and/or vegetation. The fungi-to-bacteria ratio of PLFA was constant at 5.3 ± 1.4 in all three sites, suggesting that fungi were predominant. A canonical correspondence analysis suggested that the PLFA comoosition was related to the successional ages and the developing soil properties (P 〈 0.05, ANOSIM). The chrono- sequential analysis effectively detected the successional changes in both microbial and plant communities. 展开更多
关键词 Volcanic succession Fungi-to-bacteriaratio Litter decomposition Microbial community Phospholipid fatty acids (PLFAs) Primary succession
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Modeling Biodiversity Benefits and External Costs from a Keystone Predator Reintroduction Policy
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作者 Yohan LEE Jane L. HARRISON +1 位作者 Cristina EISENBERG Byungdoo LEE 《Journal of Mountain Science》 SCIE CSCD 2012年第3期385-394,共10页
In this paper, an economic model was constructed to determine the optimal wolf population and distribution across the Northern Rocky Mountains. Both ecological and economic concepts were incorporated in an implicitly ... In this paper, an economic model was constructed to determine the optimal wolf population and distribution across the Northern Rocky Mountains. Both ecological and economic concepts were incorporated in an implicitly spatial social welfare maximization problem. This interdisciplinary model relies on multiple data sources, including current wolf population and distribution information, opportunity cost to local landowners, and contingent valuation studies to determine willingness-to-pay for wolves. Economic models tend to externalize ecological concerns and ecological models often omit the complex human dimensions of conservation policy. Accordingly, this model can serve as a guide for integrating best practices from both fields. The model presented here is sufficiently general to apply to wolves in other ecosystems and to other highly interacting species such as beavers and bison. The Northern Rocky Mountain wolf was used as an example of how this economic model works, but this model can be applied far more broadly. 展开更多
关键词 WOLF ECONOMICS BIODIVERSITY Ecological economics Opportunity cost Conservationpolicy Endangered species
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Self-renewal Capacity of Several Species of the Genus Sternbergia Possessing Medicinal Properties
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作者 Tsira Mikatadze-Pantsulaia Tinatin Barblishvili +1 位作者 Elene Japaridze Madam Kikvidze 《Journal of Agricultural Science and Technology(A)》 2016年第3期183-190,共8页
The present work dealt with sexual reproduction capacity of three relic species of the genus Sternbergia (family AmaryUidaceae) distributed in the Caucasus, i.e., Sternbergia lutea (L.) Ker Gawl. ex Spreng., Stern... The present work dealt with sexual reproduction capacity of three relic species of the genus Sternbergia (family AmaryUidaceae) distributed in the Caucasus, i.e., Sternbergia lutea (L.) Ker Gawl. ex Spreng., Sternbergiafischeriana (Herb.) Roem and Sternbergia colchiciflora Waldst. & Kit.. Under this study, the natural populations of species, which possess valuable medicinal and ornamental properties, have been assessed by experts as vulnerable, and S. colchiciflora is included in the red list of endemic plants of the Caucasus, as having status of the critically endangered species. The situation is aggravated by the poor self-regeneration capacity of these species, which is one of the main factors responsible for the sustainability of the population of this or that species in the wild. Self-regeneration capacity for sexual reproduction was investigated in the listed species of the genus Sternbergia using common methods of embryology and reproduction biology. In conditions of the National Botanical Garden of Georgia (NBGG), the species S. lutea and S. fischeriana prove to be completely infertile and propagate vegetatively by bulblets, while S. colchiciflora revealed the ability for propagation by seed. Long-term conservation of seeds of the studied species S. colchiciflora in the Caucasus Regional Seed Bank (CRSB) and establishing of living collections of this species at the experimental plot were chosen as the method for safeguarding this critically endangered species. 展开更多
关键词 Sternbergia medicinal properties vulnerable species micro- and macro-sporogenesis OVULE GERMINATION plantreproduction ex-situ conservation.
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Measurement of large deformation of nylon cord-rubber composite and effects of perpendicular loads on its stress-strain behaviors
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作者 张丰发 杜星文 于增信 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第1期34-38,共5页
Effects of transverse loads on longitudinal stress strain behaviors and longitudinal constant tensile loads on transverse stress strain behaviors of single ply of nylon cord rubber composite are studied respectively u... Effects of transverse loads on longitudinal stress strain behaviors and longitudinal constant tensile loads on transverse stress strain behaviors of single ply of nylon cord rubber composite are studied respectively under biaxial tensile condition with cruciform specimen. Effects of transverse constant tensile load on longitudinal tensile mechanical properties are indistinctive compared with corresponding uniaxial longitudinal tensile mechanical properties. It can be relative to larger difference between longitudinal and transverse mechanical properties. Its dominating failure mode is typical fiber dominated mode; However, Experiment results indicate that transverse mechanical properties of nylon cord rubber composite with longitudinal constant tensile loads are distinct from its uniaxial transverse tensile mechanical properties. It can be attribute to action of longitudinal tension that makes material rigidify in the direction perpendicular to fiber, Mode of failure is representative of matrix dominated failure. For the measurement of large deformation up to 50 percent, a special CCD imaging method is employed in the experimental investigation that makes measurement of large deformations more precise. 展开更多
关键词 nylon cord rubber composite cruciform specimen large deformation biaxial tensile condition
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