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1.
以西湖凹陷西斜坡花港组、平湖组致密砂岩储层为研究对象,通过录井资料分析及岩心和显微薄片观察,研究裂缝的宏观与微观发育特征及其影响因素.结果显示其主要发育层理缝和构造缝.层理缝主要为水平缝和低角度缝,且已被充填;构造缝主要为垂直缝和高角度缝,充填缝和未充填缝各占一半.裂缝的发育受岩性、单层厚度、断裂及地应力场的综合影响.在交会图法(定性)和概率判别法(半定量)研究的基础上,将岩心观察统计结果与常规测井曲线和成像测井成果相对比,综合预测与评价裂缝发育段,认为有利的裂缝发育层段为花港组下段和平湖组中下段.  相似文献   
2.
我国初步建立了财政性科技经费监管体系,但是在监督主体、监督制度等方面还存在缺陷,科技经费监督出现诸多问题。建立要加强宏观层面的统筹规划,建立由政府、承担单位和外部主体上下联动、横向联合的立体监督体系。  相似文献   
3.
氧化还原介体催化强化污染物厌氧降解研究进展   总被引:1,自引:0,他引:1  
 由于厌氧生物处理技术具有产生剩余污泥少、可回收能源等优点而被广泛用于处理各种有机污染物,尤其在有毒、有害、难降解污染物的去除方面取得了良好的效果。然而,厌氧生物法的处理速率通常比较低,而氧化还原介体可通过自身不断的氧化和还原来传递电子,提高电子在氧化还原反应过程中的传递速率,从而促进污染物高效厌氧降解。醌类物质和腐殖酸是应用较多的氧化还原介体,在催化难降解污染物降解方面取得了一定效果。讨论了氧化还原介体的特点、作用机制,并总结了其对偶氮染料厌氧脱色、反硝化和多氯联苯厌氧降解的强化作用,提出了氧化还原介体未来的研究方向。  相似文献   
4.
Plants often encounter unfavorable environmental conditions because of their sessile lifestyle. These adverse factors greatly affect the geographic distribution of plants, as well as their growth and productivity. Drought stress is one of the premier limitations to global agricultural production due to the complexity of the water-limiting environment and changing climate. Plants have evolved a series of mechanisms at the morphological, physiological, biochemical, cellular, and molecular levels to overcome water deficit or drought stress conditions. The drought resistance of plants can be divided into four basic types-drought avoidance, drought tolerance, drought escape, and drought recovery. Various drought-related traits, including root traits, leaf traits, osmotic adjustment capabilities, water potential, ABA content, and stability of the cell membrane, have been used as indicators to evaluate the drought resistance of plants. In the last decade, scientists have investigated the genetic and molecular mechanisms of drought resistance to enhance the drought resistance of various crops, and significant progress has been made with regard to drought avoidance and drought tolerance. With increasing knowledge to comprehensively decipher the complicated mechanisms of drought resistance in model plants, it still remains an enormous challenge to develop water-saving and drought-resistant crops to cope with the water shortage and increasing demand for food production in the future.  相似文献   
5.
在高海拔区域测制地形图,如青藏高原地区,所获取的遥感影像局部存在着大范围的高山阴影或云雪覆盖,造成立体观测地貌困难的现象,探讨应用SRTM数据对这类特殊区域地貌进行修测补绘。介绍了数据处理的作业过程,并对实验区SRTM与SPOT5影像立体测图成果进行实验对比分析,成果符合要求。  相似文献   
6.
A broker in an open e-marketplace enables buyers and sellers to do business with each other. Although a broker plays an important role in e-marketplaces, theory and guidelines for matching between buyers and sellers in multi-attribute exchanges are limited. Therefore, a challenge for a broker’s responsibility is how to maximize a buyer’s total satisfaction degree as its goals under the consideration of trade-off between a buyer’s buying quantity and price paid to a seller, and other attributes. To solve this challenge, this paper proposes an economic model-based matching approach between a buyer’s requirements and a seller’s offers. The major contributions of this paper are that (i) a broker can model a seller’s price policy as per a buyer’s buying quantity through communication between a broker and a seller; (ii) due to each buyer’s different quantity demand, a broker models a buyer’s satisfaction degree as per a buyer’s buying quantity based on communication between a broker and a buyer; and (iii) to carry out a broker’s matching processes, an objective function and a set of constraints are generated to help a broker to maximize a buyer’s total satisfaction degree. Experimental results demonstrate the good performance of the proposed approach.  相似文献   
7.
By far, the researches on how to distribute blood products among different departments in hospital have not been further studied, though the problem of blood shortage and wastage that caused by improper blood allocation is severe, which may endanger patient’s lives and impose considerable costs on hospitals. In order to solve this problem, this paper mainly studies on how to distribute the blood items among different departments within a hospital and investigates the allocation approach with the novel management method by centralizing the inventory of several different departments. By integrating the blood inventory requirements of some departments, the hospital could reduce the rate of blood shortage and wastage effectively, release the pressure of the occupancy of resources and reduce the bullwhip effect of blood products. This paper illustrates the centralization principle in hospital and formulates the mixed integer programming model to work out the optimal allocation network scheme and the optimal inventory setting for every department. And the results of the numerical example demonstrate that this centralization method could considerably reduce blood shortage and wastage in hospital by about 72% and 90% respectively. Furthermore, it could decrease the total cost by about 108,540 RMB a month on blood supply chain management in the hospital and improve the effect of some certain surgeries by transfusing the fresh blood to patients.  相似文献   
8.
Through molecular dynamics(MD)simulation,the dependencies of temperature,grain size and strain rate on the mechanical properties were studied.The simulation results demonstrated that the strain rate from 0.05 to 2 ns~(–1 )affected the Young’s modulus of nickel nanowires slightly,whereas the yield stress increased.The Young’s modulus decreased approximately linearly;however,the yield stress firstly increased and subsequently dropped as the temperature increased.The Young’s modulus and yield stress increased as the mean grain size increased from 2.66 to6.72 nm.Moreover,certain efforts have been made in the microstructure evolution with mechanical properties association under uniaxial tension.Certain phenomena such as the formation of twin structures,which were found in nanowires with larger grain size at higher strain rate and lower temperature,as well as the movement of grain boundaries and dislocation,were detected and discussed in detail.The results demonstrated that the plastic deformation was mainly accommodated by the motion of grain boundaries for smaller grain size.However,for larger grain size,the formations of stacking faults and twins were the main mechanisms of plastic deformation in the polycrystalline nickel nanowire.  相似文献   
9.
文章在分析广西高技术产业发展现状基础上,构建高技术产业科技创新能力评价指标体系,运用熵值法,基于2015—2019年面板数据对广西高技术产业的创新能力进行实证研究.研究表明:广西高技术产业创新能力在西部五省中处于较低水平;广西高技术创新产出实力略低于创新投入实力,创新技术吸收实力仍相对较弱;广西高技术四大行业创新能力存在差异,即电子及通信设备制造产业科技创新投入和产出效果最好,医药制造业和电子通信及装备制造业创新投入高,创新产出评分偏低,医疗仪器设备及仪器仪表制造产业和计算机及办公设备制造产业创新吸收能力很弱.基于以上结论,文章从加大创新资源投入、推动创新平台建设、加强人才队伍建设等方面提出了对策建议.  相似文献   
10.
中国经济发展过程中存在区域发展不平衡现象,这种不平衡现象对公司绩效产生了重要影响。基于2003-2015年沪、深两市A股上市公司数据,以管理费用率度量上市公司管理层与股东间的第一类代理成本,以其他应收款占比度量上市公司控股股东与中小股东之间的第二类代理成本,采用多元回归和中介效应检验程序,实证检验了外部治理环境通过两类代理成本的中介作用对上市公司绩效影响的内在机理。研究结果表明,外部治理环境的提升能够显著的降低两类代理成本,进而提高上市公司的绩效,两类代理成本在外部治理环境影响公司绩效的过程中发挥显著的部分中介作用。  相似文献   
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