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排序方式: 共有190条查询结果,搜索用时 15 毫秒
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Neural Computing and Applications - This study addresses a many-to-many hub location-routing problem where the best-found locations of hubs and the best-found tours for each hub are determined with...  相似文献   
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用特征曲线法确定油井水侵途径   总被引:1,自引:0,他引:1  
对油井水淹动态进行分析,准确确定油井出水原因,是提高堵水工艺措施效果的关键。常规的油井出水原因分析方法,因本身的局限性,或是费用高而使其应用受到限制。所提出的含水特征曲线方法能够有效地分析机械采油井、自喷井及停产井的含水动态,并能够简捷地确定油井的出水原因。  相似文献   
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Among the high carbohydrate content the cane molasses contains considerable amount of nitrogen compounds including proteins and amino acids. Protein hydrolyzates showed the presence of 16 amino acids with aspartic and glutamic acids and alanine as the major acids in both states bound and free, and there were two unidentified N-containing free acids. Fe, Zn, Mn and Cu were predominant microminerals, K and P were found to be present and in smaller quantities Na.  相似文献   
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Polypropylene(PP)/Polystyrene(PS) (PP/PS = 80/20) blend with different types of fillers were prepared by using melt method. Four different types of fillers, namely mesoporous MCM-41 (without template), nano-SiO2, Polymethylmethacrylate (PMMA)/MCM-41 and PMMA/SiO2 were considered. For PMMA/MCM-41 filler, the synthesis of the filler consisting of entrapped strand of PMMA within the pores of mesoporous MCM-41 (without template) was described. The mechanical properties of the blend determined as the nano-fillers contents and the different types of blend were found to vary with the different interface between fillers and the matrix. SEM revealed a good interaction between the matrix phases and PMMA/MCM-41 or MCM-41 (without template). The decreased Tg of PS implied that the good adhesion between PP and PS blend was obtained by adding PMMA/MCM-41 nano-filler.  相似文献   
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Scientometrics - This study aims to analyze 343 retraction notices indexed in the Scopus database, published in 2001–2019, related to scientific articles (co-)written by at least one author...  相似文献   
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Leakages result in considerable loss of water in water pipe networks. Therefore it is an important issue to detect leakage amount and its approximate location. Leakages in water distribution system are directly related to the operating pressure. In the current study, a new model is proposed for leakage amount and location detection and it is applied into two benchmark water distribution networks. In the proposed method, the water distribution networks are divided into three pressure zones in order to consider the leakage differences in different operating pressures. Then, nodal pressures and demands are calibrated using a new multi objective ant colony based optimization model. In this method, leaks are simulated as extra nodal demands. For determining the nodes where leakage happens, a probability based scheme is used. The leakage occurrence probability varies depending on the pressure zone that each node is located. The results illustrate the applicability of the proposed model for detecting the leakages in water distribution systems.  相似文献   
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Porous materials are ubiquitous in nature and have found a wide range of applications because of their unique absorption, optical, mechanical, and catalytic properties. Large surface‐area‐to‐volume ratio is deemed a key factor contributing to their catalytic properties. Here, it is shown that introducing tunable nanopores (50–700 nm) to organic semiconductor thin films enhances their reactivity with volatile organic compounds by up to an order of magnitude, while the surface‐area‐to‐volume ratio is almost unchanged. Mechanistic investigations show that nanopores grant direct access to the highly reactive sites otherwise buried in the conductive channel of the transistor. The high reactivity of nanoporous organic field‐effect transistors leads to unprecedented ultrasensitive, ultrafast, selective chemical sensing below the 1 ppb level on a hundred millisecond time scale, enabling a wide range of health and environmental applications. Flexible sensor chip for monitoring breath ammonia is further demonstrated; this is a potential biomarker for chronic kidney disease.  相似文献   
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