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排序方式: 共有1177条查询结果,搜索用时 140 毫秒
111.
介绍一种新的内浮顶油罐计量口,它克服了现行计量口操作不便的缺点。  相似文献   
112.
本文重点论述了中国东部三大勘探领域之一的内蒙裂谷盆地群油田的发现过程、勘探果、石油地质特征及其勘探战略部署意见。  相似文献   
113.
根据内蒙古河套灌区引黄灌溉工程实际,对渠井联合运用优化调度地面水和地下水后的地下水位调控规律、土壤水盐动态特征、灌溉土壤盐分变化等进行了分析。通过渠井优化调度、以灌代徘利用地下水,改变了灌区水盐动态形成条件,地厂水位下降,夏灌期地下水平均埋深为1.88m,秋灌期为1.87m,秋浇期为1.50m,冻融期为1.78m。地下水矿化度逐渐减小,淋洗排盐作用增强,表层土壤积盐过程改变为土壤逐步脱盐过程,水盐动态进入良性循环。渠井联合运用的优化决策,可广泛应用于河套引黄灌区灌排工程配套及管理之中。  相似文献   
114.
Traffic asymmetry between uplink and downlink is expected to be a remarkable 3G characteristic in cellular mobile multimedia communications. CDMA system with TDD is a good solution to this traffic asymmetry. However, the level of traffic asymmetry may be significantly different from a cell to another cell. To tackle this problem and to support the traffic hot spot, crossed slots are examined. The use of crossed slots is restricted within a certain range of a cell by investigating the inter-cell interference and the maximum planned load factor. We examine the radius of inner zone and discuss the capacity of downlink crossed slots for various neighbor cell environments. Computational results show that the capacity increase in the target cell is outstanding by reducing the service range of neighbor cells. When all six neighbors reduce their service range by 20%, the capacity at target cell crossed slot is increased by 35%. Monte Carlo simulation is performed with large scale fading to verify the numerical analysis.
Chae Y. LeeEmail:
  相似文献   
115.
尚大为  吴晓君 《山西建筑》2009,35(34):19-21
以创新建筑为出发点,分析了国外进化式建筑的实例,通过此来论证在蒙古包中可应用的进化式生态措施,也就是在原有生态技术策略上更应该结合自然,如材料的充分利用、有效的形式和构造、能源功效、牢固性等。  相似文献   
116.
川中安岳气田震旦系灯影组四段储层受桐湾II幕表生岩溶作用改造与丘滩相联合控制,岩性复杂、纵横向非均质性强,且在台缘和台内区单井产能差异较大(前者明显优于后者)。为实现川中安岳气田震旦系灯影组四段台缘带高效开发、台内区储量规模升级、优质储层地震精细预测等目标,通过实钻井岩心及薄片观察,结合分析化验、地震及测录井等资料,分析了台缘—台内区储层共性及差异性表现,并探讨了其控制因素。结果表明:台缘区与台内区储集岩石类型、储集空间、储集类型基本一致,但台缘—台内区储层内部溶蚀孔洞发育程度以及物性均呈减弱趋势,优质储层发育程度、品质及发育位置不同,储层组合类型存在差异。影响储层差异大的主要因素包括有利丘滩复合体发育程度和桐湾II幕表生岩溶作用强度;根据储层发育特征及分布规律研究以及高产井地震反射模式分析,优选优质储层发育区块进行勘探,获得了良好生产应用效果,实现了安岳气田台缘带的储量规模探明和高效开发,提高了台内区优质储层钻遇率和单井产量,实现了储量规模升级。  相似文献   
117.
为了提高输送机内、外链板孔的加工精度及加工效率,该文设计了一套新型链板冲孔模具,可以准确、高效地加工输送机链板内孔,确保了产品质量。  相似文献   
118.
The layer-by-layer (LBL) polyelectrolyte deposited membranes have drawn increasing attention in various applications due to the ease of selective layer formation and their stability and versatility. In this study, the LBL deposition was performed at the inner surface of the polyethersulfone (PES) hollow fiber substrate to form composite nanofiltration (NF) membrane. The semi-dynamic deposition procedure was adopted with the aid of syringes. The newly developed inner deposited (id-LBL) membranes were then tested in NF and forward osmosis (FO) applications and the performance were compared with outer surface deposition as well as some literature data. The id-LBL membranes could not only withstand higher operating pressure but also possess superior hardness rejection especially in high concentration mixed salt solutions (more than 95% rejection to Mg2+ and Ca2+ in a 5000 ppm total dissolved salt (TDS) mixture under 4.8 bar). As for the FO process, with only two layer deposition, the id-LBL membranes also demonstrated significant performance improvement with increased water flux (up to 70 L/m2 h using 0.5 M MgCl2 as draw solution in active layer facing draw solution configuration) and reduced salt leakage (around 0.5 g/m2 h using 1 M MgCl2 draw solution in active layer facing feed water configuration). This study suggests that for hollow fiber substrate, the inner surface is more suitable for the formation of the selective layer via LBL deposition than the outer surface.  相似文献   
119.
At present, several composite insulation systems were proposed that can be used for passive insulation systems, including foam-variable density multilayer insulation (VDMLI), aerogel-VDMLI and hollow glass microspheres (HGMs)-VDMLI. The passive insulation systems with different inner material (IM) showed different performances. However, the relationship between the average thermal conductivity of IM and the insulation performance of the whole system has rarely been investigated. It is of great significance for efficient configuration and matching of the passive insulation system. In this paper, a series of average thermal conductivity of IM were assumed to predict the insulation performance of the whole system at 20 K–300 K and high vacuum. In order to further illustrate the relationship between IM and MLI/VDMLI, the foam was replaced by the HGMs as 5 mm a unit forming a series of HGMs-foam-MLI/VDMLI insulation systems. The performance of the systems was investigated. After the foam was completely replaced by the HGMs, the performance of MLI and VDMLI systems was improved 33% and 13%, respectively. Moreover, each mode of heat transfer including solid conduction, radiation, and gas conduction for foam-MLI/VDMLI and HGMs-MLI/VDMLI insulation systems were calculated and analyzed.  相似文献   
120.
赵永江 《机械管理开发》2005,(2):120-120,122
介绍了内部质量审核的三种组织模式,提出了应注重对内审的策划,阐明了提高内审有效性的方法。  相似文献   
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