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11篇 您的检索式:作者名="ZHENG Defeng"
    题名 作者 年代 出处 被引量
1Water resource utilization efficiency and spatial spillover effects in China显示文摘基于水脚印和灰色的省的面板数据浇脚印,并且在数据包封分析的帮助下当模特儿就而言并且没有考虑不受欢迎的产量,这份报纸从 1997 ~ 2011 在中国估计水资源利用效率。空间 weighting 矩阵基于经济空间的距离功能被建立讨论水资源利用效率的空间自相关。在绝对集中模型的帮助下,这份报纸断定那在那里存在在水资源利用效率的集中。在考虑并且没有考虑不受欢迎的产量的条件下面,完成集中的一半的程度分别地花大约 52.6 和 5.6 年。由空间 Durbin econometric 模型的平均数,这份报纸在中国学习省的水资源利用效率的空间溢出效果。结果如下。1 ) 与考虑并且没有考虑不受欢迎的产量,在在中国的省的水资源效率有重要空间关联。2 ) 在二个盒子下面,空间 autoregressive 系数() 分别地是 0.278 和 0.507,在 1% 意义水平。在那里存在省的水资源利用效率的空间溢出效果。3 ) 与考虑不受欢迎的产量,教育资金的这些因素,交通基础结构,和工业、农业的水消费比例有积极影响。外国直接投资的这些因素,工业增值水消费每 1 万,元,人均的水消费,和全部的降水有否定影响。4 ) 没有考虑不受欢迎的产量, GDP 的因素在水资源利用效率上每劳动者有更大的积极重要影响。然而,在 1 万元和交通基础结构的工业增值水消费的事实没有重要影响。5 ) 不管水资源利用效率的不受欢迎的输出,对在中国的现在的真实的水资源利用的评价将被弄歪,政策制定的愿望被误导。就环境因素而言的水效率措施(例如灰色的水脚印) 是更合理的。SUN Caizhi ZHAO Liangshi ZOU Wei ZHENG Defeng 2014Journal of Geographical Sciences2014,24,5:29
2Empirical Research on Carrying Capacity of Human Settlement System in Dalian City, Liaoning Province, China显示文摘Using the theories of population carrying capacity and ecological elasticity in other fields for reference, the connotation of regional human settlement system was defined from the viewpoint of the complex relationship among the factors such as regional population, resources, environment and economic and social development in the context of China′s rapid urbanization. Then the concept and characterization methods of the regional human settlement carrying capacity were proposed by means of population scale. Furthermore, a model of carrying capacity-pressure-state-response(CPSR) on regional human settlement system was established by referencing pressure-state-response(PSR) model, and the Catastrophe Theory was introduced to determine the corresponding standards of multi-criteria programming and evaluation. Taking Dalian City, Liaoning Province, China as an example, an empirical analysis on evaluation of human settlement system from 2000 to 2012 was carried out. The results showed that the carrying capacity of human settlement system in Dalian was fluctuating between 9.6 × 106 to 10 × 106 persons with a quantitative stage of the dynamic regulation. During the research period the load index of human settlement system in Dalian dropped from 0.96 to 0.84 with a lower pressure of human settlement system than the national average level. And the emergency response grades of human settlement system in Dalian were kept in grade Ⅱ(orange warning) or grade Ⅲ(yellow warning). Human settlement system of Dalian was in slight security state as a whole, but the load had a tendency of increase in recent years. The related departments should pay close attention to regional human settlement system and take active measures to improve human settlement by both intensity control and total quantity control. By comparison, analysis and discussion, it was considered that the results were basically accordded with the current situations of human settlement in Dalian, and the evaluation results were more reliable, visualized and easily applied in practice. Therefore, the above-mentioned concepts, characterization and evaluation methods of the regional human settlement system and carrying capacity could provide a new thought and method for quantitative evaluation of human settlement.ZHENG Defeng ZHANG Yu ZANG Zheng SUN Caizhi 2015Chinese Geographical Science2015,25,2:13
3The structural characteristics, age of origin, and tectonic attribute of the Erguna Fault, NE China显示文摘The Erguna Fault runs along the east bank of the Erguna River in NE China and is a large-scale ductile shear zone comprising granitic mylonites. This paper reports on the geometry, kinematic indicators, and 40Ar/39 Ar biotite ages of the granitic mylonites, to constrain the structural characteristics, forming age, and tectonic attribute of the Erguna ductile shear zone. The zone strikes NE and records a top-to-the-NW sense of shear. A mylonitic foliation and stretching lineation are well developed in the mylonites, which are classified as S-L tectonites. Logarithmic flinn parameters(1.18–2.35) indicate elongate strain which approximates to plane strain. Kinematic vorticity numbers are 0.42–0.92 and 0.48–0.94, based on the polar Mohr diagram and the oblique foliation in quartz ribbons, respectively, suggesting that the ductile shear zone formed under general shear, or a combination of simple and pure shear. According to finite strain and kinematic vorticity analyses, the Erguna Fault is a lengthening-thinning ductile shear zone that formed by extension. The deformation behavior of minerals in the mylonites indicates that the fault was the site of three stages of deformation: an initial stage of middle- to deep-level, high-temperature shear, a post-stress recovery phase of high-temperature static recrystallization, and a final phase of low-temperature uplift and cooling. The 40Ar/39 Ar plateau ages of biotite from the granitic mylonites are 106.16 ± 0.79 and 111.55 ± 0.67 Ma, which constrain the timing of low-temperature uplift and cooling but are younger than the ages of metamorphic core complexes(MCCs) in the Transbaikalia-northeast Mongolia region. Using measured geological sections, microtectonics, estimates of finite strain and kinematic vorticity, and regional correlations and geochronology, we conclude that the Erguna Fault is an Early Cretaceous, NNE-trending, large-scale, sub-horizontal, and extensional ductile shear zone. It shares a similar tectonic background with the MCCs, volcanic fault basins, and large and super-large volcanic-hydrothermal deposits in Transbaikalia-northeast Mongolia and the western Great Khingan Mountains, all of which are the result of overthickened crust that gravitationally collapsed and extended in the Early Cretaceous after plate collision along the present-day Sino-Russia-Mongolia border tract.ZHENG Han SUN XiaoMeng ZHU DeFeng TIAN JingXiong HE Song WANG YingDe ZHANG XuQing 2015Science China Earth Sciences2015,58,9:3
4RNA-Seq Study Reveals AP2-Domain-Containing Signalling Regulators Involved in Initial Imbibition of Seed Germination in Rice显示文摘A number of internal signals are required for seed germination.However,the precise signalling responses in the initial imbibition of seed germination are not yet fully understood in rice.In this study,the RNA sequencing(RNA-Seq)approach was conducted in 8 h imbibed seeds to understand the signalling responses in the initial imbibition of rice seed germination.A total of 563 differentially expressed genes(DEGs)with at least 4-fold change were identified in 8 h imbibed seeds compared to dry seeds.MapMan analysis revealed that the majority of signalling response-related DEGs were hormone-and transcription factor-related genes,in which the largest number of DEGs belong to the AP2-domain-containing regulators,and their expressions were significantly induced in the initial imbibition of seed germination in rice.Moreover,at least five AP2-domain-containing transcription factor OsDREBs were identified in the initial imbibition of rice seed germination,and the expressions of 251 DEGs were putatively regulated by OsDREBs through the dehydration-responsive element(DRE)cis-element assay.It suggested that the OsDREBs might play important roles in the regulation of initial seed imbibition in rice.The identified genes provide a valuable resource to study the signalling regulation of seed germination in the future.HE Yongqi ZHAO Jia FENG Defeng HUANG Zhibo LIANG Jiaming ZHENG Yufei CHENG Jinping YING Jifeng WANG Zhoufei 2020Rice science2020,27,4:2
5Study on rheological behavior of poly (bulylene terephthalate) /montmorillonite nanocomposites 显示文摘WU Defeng ZHOU Chixing HONG Zheng 2005Eur Polym J2005,,41:1
6Using X-ray computed tomography and micro-Raman spectrometry to measure individual particle surface area, volume, and morphology towards investigating atmospheric heterogeneous reactions显示文摘Heterogeneous reactions on the aerosol particle surface in the atmosphere play important roles in air pollution, climate change, and global biogeochemical cycles. However, the reported uptake coefficients of heterogeneous reactions usually have large variations and may not be relevant to real atmospheric conditions. One of the major reasons for this is the use of bulk samples in laboratory experiments, while particles in the atmosphere are suspended individually. A number of technologies have been developed recently to study heterogeneous reactions on the surfaces of individual particles. Precise measurements on the reactive surface area, volume, and morphology of individual particles are necessary for calculating the uptake coefficient, quantifying reactants and products, and understanding the reaction mechanism better. In this study, for the first time we used synchrotron radiation X-ray computed tomography(XCT) and micro-Raman spectrometry to measure individual CaCO_3 particle morphology, with sizes ranging from 3.5–6.5 μm. Particle surface area and volume were calculated using a reconstruction method based on software threedimensional(3-D) rendering. The XCT was first validated with high-resolution fieldemission scanning electron microscopy(FE-SEM) to acquire accurate CaCO_3 particle surface area and volume estimates. Our results showed an average difference of only 6.1% in surface area and 3.2% in volume measured either by micro-Raman spectrometry or X-ray tomography. X-ray tomography and FE-SEM can provide more morphological details of individual Ca CO3 particles than micro-Raman spectrometry. This study demonstrated that X-ray computed tomography and micro-Raman spectrometry can precisely measure the surface area, volume, and morphology of an individual particle.Mingjin Wang Nan Zheng Tong Zhu Jing Shang Ting Yu Xiaojuan Song Defeng Zhao Yong Guan Yangchao Tian 2018Journal of Environmental Sciences2018,30,7:1
7Study on rheological behaviors of poly(butylene terephthalate)/montmorillonite nanocomposites显示文摘Defeng Wu Chixing Zhou Zheng Hong 2005European Polymer Journal2005,41,9:1
8Study on rheological behaviour of poly ( butyleue terephthalate )/montmorillonlte nanocomposites显示文摘Defeng Wu Chixing Zhou Zheng Hong 2005European Polymer Journal2005,41,9:1
9Accuracy analysis of parallel plate interferometer for angular displacement measarement显示文摘Zheng Defeng Wang Xiangzhao Li Zhongliang 2008Optics & Laser Technology2008,40,1:1
10Study on Rheological Behaviour of Poly (butylenes terephthalate)/ Montmorillonite Nanocomposites 显示文摘Defeng Wu Chixing Zhou Zheng Hong 2005European Polymer Journal2005,41,9:1
11Predicting impact forces on pipelines from deep-sea fluidized slides:A comprehensive review of key factors显示文摘Deep-sea pipelines play a pivotal role in seabed mineral resource development,global energy and resource supply provision,network communication,and environmental protection.However,the placement of these pipelines on the seabed surface exposes them to potential risks arising from the complex deep-sea hydrodynamic and geological environment,particularly submarine slides.Historical incidents have highlighted the substantial damage to pipelines due to slides.Specifically,deep-sea fluidized slides(in a debris/mud flow or turbidity current physical state),characterized by high speed,pose a significant threat.Accurately assessing the impact forces exerted on pipelines by fluidized submarine slides is crucial for ensuring pipeline safety.This study aimed to provide a comprehensive overview of recent advancements in understanding pipeline impact forces caused by fluidized deep-sea slides,thereby identifying key factors and corresponding mechanisms that influence pipeline impact forces.These factors include the velocity,density,and shear behavior of deep-sea fluidized slides,as well as the geometry,stiffness,self-weight,and mechanical model of pipelines.Additionally,the interface contact conditions and spatial relations were examined within the context of deep-sea slides and their interactions with pipelines.Building upon a thorough review of these achievements,future directions were proposed for assessing and characterizing the key factors affecting slide impact loading on pipelines.A comprehensive understanding of these results is essential for the sustainable development of deep-sea pipeline projects associated with seabed resource development and the implementation of disaster prevention measures.Xingsen Guo Ning Fan Defeng Zheng Cuiwei Fu Hao Wu Yanjun Zhang Xiaolong Song Tingkai Nian 2024International Journal of Mining Science and Technology2024,34,2:0
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