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Abstract: Poverty in America has grown persistently throughout the twentieth century.
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摘要:美国的贫困现象在整个20世纪持续增长。 |
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Abstract: Power quality and its monitoring technique is the important research area in electrical engineering nowadays.
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摘要:电能质量监测是当前电工领域的研究热点。 |
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Abstract: Precast floorslabs are widely used in residential buildi ngs in order to quicken the progress of construction.Yet some quality problems accoringly arise,one of which is the fissure along the splice of the precast floor slab.This essay analyses t
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文摘:在住宅的设计与建设中大量采用预制楼板结构,虽然加快了施工进度,但也出现了一些问题,预制楼板板缝方向产生裂缝就是其中之一,本文对其原因进行了分析,并提出了有效的防治措施. |
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Abstract: Precisely predicting the amount of gas emitted from the coal face is of great importance in the design of mine and production safety.
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文摘:正确预测瓦斯涌出量,对于指导矿井设计和安全生产有重要意义。 |
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Abstract: Presented is a newly developed measuring &, control system used for internal combustion engine rig test.
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文摘:介绍了一种新开发的适用于发动机鉴定试验的自动测量控制系统。 |
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Abstract: Presents the model established for calculation of reliability of connecting rod fatigue strength, and stress analysis made with the connecting rod body of diesel engine,and the reliability calculations made with the connecting rod of 6200ZCL die
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文摘:连杆的主要破坏形式是疲劳破坏,疲劳破坏是连杆按强度失效的主要故障模式.本文根据机构可靠性的基本原理,建立了连杆疲劳强度可靠性的计算模型.对直列式柴油机连杆杆身进行了应力分析,并结合6200ZCL型柴油机连杆的具体实例,进行了无限寿命下的疲劳强度可靠性计算,所得结果与实际工程情况相符.阐明了所提供方法的具体应用,这种方法对其它寿命很长的机构构件同样适用. |
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Abstract: Pressure separation is usually controlled by the following factors, such as subsidence rate, sediment types and diagenesis during the diagenetic evolution, as a result the pressure gradient is uncontinuous.
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文摘:地层压力分隔化是由于沉积物在成岩演化过程中受各种因素,如沉积速率、沉积物类型以及成岩作用的影响,使地层中的流体压力梯度呈现出随深度变化不连续的一种现象。 |
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Abstract: Principles of nanometer materials science,basic methods preparing nanometer materials and their application prospects in petrochemical catalysts, assistants and additives, were introduced together with practical examples of initial study and app
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文摘:对纳米材料科学的基本原理、纳米材料制备的一些方法,以及纳米材料在石油化工催化剂、助剂和添加剂中的应用前景做了介绍,并列举了一些处于起始阶段的研究和应用实例。 |
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Abstract: Problems caused in designing and management including configuring regulating devices, deciding spaces of the last pipelines, and working-out irrigation scheme in reason using drip irrigation in green houses and in covered lands are raising in re
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文摘:近几年来温室、大棚种植蔬菜采用滴灌技术的越来越多,但有些工程无论设计上、管理上都存在一些问题,包括调压设备的合理配置,按土壤、作物、灌水器及滴灌总水量合理确定毛管(或滴灌带)的间距,以及按大棚蔬菜的耗水特性合理确定灌溉制度等,上述各项确定的不合理,不但直接影响效益,严重时可导致工程失败,值得重视。 |
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Abstract: Problems of water resource limit the agricultura l developmentand econ omical development of Guizhou Karst Region.
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文摘:水资源问题制约了贵州岩溶地区农业和地区经济的发展。 |
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Abstract: Proceed in start from position of ecological constraction and agricultural sustainable development strategy of Ningxia part in Loess Plateau, the article discusses existing problems and harnessing experiences of Ningxia ecological environment an
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文摘:从黄土高原宁夏部分生态建设与农业可持续发展的战略地位出发,阐述了宁夏生态环境存在的问题与治理经验,并提出了如何改善宁夏生态环境、进行保护性建设的一些可行性建议。 |