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连续重整4M50型往复压缩机不上量原因分析及解决措施
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作者 刘立平 卢世忠 +2 位作者 马平定 李玉军 詹金磊 《自动化与仪器仪表》 2013年第2期128-129,共2页
就某炼油厂连续重整装置4M50型往复式氢气压缩机停工检修复工后不上量故障现象进行了描述,结合拆检状况和整个管网系统实际对压缩机不上量原因进行了详细分析,最后给出解决措施。
关键词 连续重整 往复式压缩机 上量 气阀
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含油污水输送泵不上量故障分析与处理 被引量:2
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作者 梁彬 秦琪 范志卿 《机电工程技术》 2022年第5期283-286,共4页
针对某化工企业含油污水输送泵在满负荷工作状态下出口流量不足,运行过程中存在振动值偏高、噪声超标等问题,对该泵进行拆卸检查,拆检过程发现泵轴上支撑轴套磨损严重,两级叶轮入口和出口隔板位置均存在未焊满情况,且隔舌起点和叶轮口... 针对某化工企业含油污水输送泵在满负荷工作状态下出口流量不足,运行过程中存在振动值偏高、噪声超标等问题,对该泵进行拆卸检查,拆检过程发现泵轴上支撑轴套磨损严重,两级叶轮入口和出口隔板位置均存在未焊满情况,且隔舌起点和叶轮口环配合间隙过大。分析发现,单蜗壳压出室在运行过程中存在不平衡的径向力,会对支撑位造成冲击,引起支撑轴套磨损;同时叶顶间隙大、隔板未焊满会造成内泄漏形成泄漏涡,降低泵的效率。针对以上问题,决定增加防漩涡板,并将单蜗壳改造为双蜗壳系统平衡流体脉冲压力,对隔板未焊满处进行补焊,减少隔舌起点和叶轮出口配合间隙,优化叶轮口环配合间隙等,以防止泄漏涡的形成。通过以上措施,输送泵运转正常,流量达到设计要求,振动值、噪声均在规定范围内。 展开更多
关键词 含油污水输送泵 上量 防漩涡板 双通道蜗壳
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对襄阳北编组站实施内涵增产上量的调查与思考 被引量:1
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作者 王桦 《中国铁路》 2012年第10期17-20,共4页
针对襄阳北编组站面临的运能极度紧张、作业组织复杂、施工任务繁重等一系列困难和压力,积极采取有效措施,变压力为动力,变常规为精细,变传统为科学,变单一为统一,变被动为主动,不断提升思想观念,创新生产组织模式和现代管理模式,构建... 针对襄阳北编组站面临的运能极度紧张、作业组织复杂、施工任务繁重等一系列困难和压力,积极采取有效措施,变压力为动力,变常规为精细,变传统为科学,变单一为统一,变被动为主动,不断提升思想观念,创新生产组织模式和现代管理模式,构建以车站为主导的站区"大运输"格局,取得了显著成效,编组站工作量实现跳跃式增长,功能得到充分发挥,同时作业效率处于全路同类编组站前列,凸现了路网畅通的边际效益。 展开更多
关键词 襄阳北编组站 增产上量 工作效率 边际效益
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优化运输组织在助推麻城站货运上量中的实践与分析 被引量:1
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作者 王健 《科学技术创新》 2018年第27期115-116,共2页
针对运输组织在麻城站装车上量中的一些实践与思考进行分析。
关键词 麻城站 货运上量 分析
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自吸泵不上量原因分析及处理措施 被引量:1
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作者 武立峰 《广东化工》 CAS 2016年第14期203-203,205,共2页
文章针对自吸泵不上量的故障原因进行分析,从工艺操作、仪表控制、泵本身设计缺陷等方面,提出改进意见,改善其运行状况,以提高其运行可靠性。
关键词 自吸泵 上量 故障分析 处理措施
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煤气鼓风机油泵不上量分析及处理
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作者 姚春刚 朱春波 沙崇军 《风机技术》 2009年第2期81-82,共2页
对煤气鼓风机油泵不上量的故障进行了具体分析,介绍了故障的排除方法,提出了解决此类问题的建议。
关键词 煤气鼓风机 齿轮泵 上量 改造
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分子筛输送泵上量不稳故障分析及改进
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作者 朱辉 《化工管理》 2016年第30期201-201,共1页
针对三套分子筛生产装置二交分子筛输送泵13/7、8频繁发生上量不稳,造成后系统产品质量产量波动的故障,通过对工况,输送泵及其出入口管线,阀门等阻力分析计算,找出了故障发生的原因,并提出了相应的改进措施,实现设备平稳运行,保证装置... 针对三套分子筛生产装置二交分子筛输送泵13/7、8频繁发生上量不稳,造成后系统产品质量产量波动的故障,通过对工况,输送泵及其出入口管线,阀门等阻力分析计算,找出了故障发生的原因,并提出了相应的改进措施,实现设备平稳运行,保证装置的连续生产。 展开更多
关键词 浆液输送泵 上量不稳 气蚀 管阻
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焦化蒸汽往复泵不上量问题的解决
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作者 马慧 马中江 《化工管理》 2017年第27期248-249,共2页
针对焦沥车间蒸汽往复泵频繁出现不上量故障,通过原因分析,找出问题,并对单向阀进行改造,使问题得以解决,取得了良好的效果。
关键词 蒸汽往复泵 上量 单向阀
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成都铁路局卸车上量工作研究
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作者 杨文德 《成铁科技》 2015年第3期26-27,共2页
本文对制约我局卸车再上量的困难和问题进行了梳理,在此基础上对我局卸车再上量工作提出了相关建议和措施。
关键词 卸车 上量 措施
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铁路多点发力积极调整应对策略确保装车上量
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作者 李杰 《中小企业管理与科技》 2019年第33期100-101,共2页
随着社会经济的不断发展以及铁路运输行业的迅猛进步,铁路运输量逐年提升,为了能够更好地促进铁路运输行业的发展与进步,必须要不断加强铁路货物运输水平,通过多点发力积极调整应对策略,保证装车上量。论文主要针对铁路局提高装车上量... 随着社会经济的不断发展以及铁路运输行业的迅猛进步,铁路运输量逐年提升,为了能够更好地促进铁路运输行业的发展与进步,必须要不断加强铁路货物运输水平,通过多点发力积极调整应对策略,保证装车上量。论文主要针对铁路局提高装车上量的相关对策进行探究。 展开更多
关键词 铁路 多点发力 装车上量
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等距离正圆柱投影在极区海图中的应用研究 被引量:4
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作者 张志衡 彭认灿 +2 位作者 董箭 褚永磊 方荣华 《海洋测绘》 CSCD 2018年第4期67-70,74,共5页
针对当前极区投影方式在极区海图编制及应用方面不完全适用的问题,结合现有航海图制作及使用习惯,提出了选用等距离正圆柱投影作为极区海图投影的设想,并分析了其适用性及应用方面存在的不足。重点对该投影海图使用过程中较为关注的等... 针对当前极区投影方式在极区海图编制及应用方面不完全适用的问题,结合现有航海图制作及使用习惯,提出了选用等距离正圆柱投影作为极区海图投影的设想,并分析了其适用性及应用方面存在的不足。重点对该投影海图使用过程中较为关注的等角航线展绘和图上方位、距离量测等应用问题进行了研究并提出相应的解决方法。同时通过具体算例,证明了所提方法的可行性,为该投影在极区海图中的应用奠定了基础。 展开更多
关键词 海图编制 等距离正圆柱投影 极区海图 等角航线 上量
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Uplink capacity analysis of single-user SA-MIMO system
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作者 戴建新 陈明 钟佩蓉 《Journal of Southeast University(English Edition)》 EI CAS 2013年第1期1-6,共6页
A novel framework of which combines smart antennas multiple antenna systems, (SA) with multiple-input multiple-output (MIMO) at the receiver, is proposed. The uplink SA-MIMO system is investigated. The joint optim... A novel framework of which combines smart antennas multiple antenna systems, (SA) with multiple-input multiple-output (MIMO) at the receiver, is proposed. The uplink SA-MIMO system is investigated. The joint optimization problem corresponding to the uplink capacity of the single-user SA-MIMO system is deduced. Then the closedform expression of the capacity is obtained in the case of equal power allocation and the same direction-of-arrivals (DOAs) from different transmit antennas at the same antenna array, and an upper bound of the capacity is also given in the case of different DOAs at the same antenna array. After that, for the general case, a suboptimal method for the capacity optimization problem is presented. Some numerical results are also given to compare the capacities of conventional MIMO and SA-MIMO systems and show that the proposed method is viable. 展开更多
关键词 smart antennas multiple-input multiple-output(MIMO) uplink capacity BEAM-FORMING
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Influence of Epistasis and QTL×Environment Interaction on Heading Date of Rice(Oryza sativa L.) 被引量:3
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作者 刘桂富 杨剑 +1 位作者 徐海明 朱军 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第7期608-615,共8页
QTLs for heading date of rice (Oryza sativa L.) with additive, epistatic, and QTL × environment (QE) interaction effects were studied using a mixed-model-based composite interval mapping (MCIM) method and a... QTLs for heading date of rice (Oryza sativa L.) with additive, epistatic, and QTL × environment (QE) interaction effects were studied using a mixed-model-based composite interval mapping (MCIM) method and a double haploid (DH) population derived from IR64/Azucena in two crop seasons. Fourteen QTLs conferring heading date in rice, which were distributed on ten chromosomes except for chromosomes 5 and 9, were detected. Among these QTLs, eight had single-locus effects, five pairs had double-locus interaction effects, and two single-loci and one pair of double-loci showed QTL × environment interaction effects. All predicted values of QTL effects varied from 1.179 days to 2.549 days, with corresponding contribution ratios of 1.04%-4.84%. On the basis of the effects of the QTLs, the total genetic effects on rice heading date for the two parents and the two superior lines were predicted, and the putative reasons for discrepancies between predicted values and observed values, and the genetic potentiality in the DH population for improvement of heading date were discussed. These results are in agreement with previous results for heading date in rice, and the results provide further information, which indicate that both epistasis and QE interaction are important genetic basis for determining heading date in rice. 展开更多
关键词 quantitative trait locus (QTL) EPISTASIS QTL ×environment interaction heading date rice (Oryza sativa L.)
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Delay and Energy Efficient Design of an On-Chip Bus with Repeaters Using a New Spatial and Temporal Encoding Technique
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作者 张庆利 王进祥 +1 位作者 喻明艳 叶以正 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第4期724-732,共9页
On-chip global buses in deep sub-micron designs consume significant amounts of energy and have large propagation delays. Thus, minimizing energy dissipation and propagation delay is an important design objective. In t... On-chip global buses in deep sub-micron designs consume significant amounts of energy and have large propagation delays. Thus, minimizing energy dissipation and propagation delay is an important design objective. In this paper, we propose a new spatial and temporal encoding approach for generic on-chip global buses with repeaters that enables higher performance while reducing peak energy and average energy. The proposed encoding approach exploits the benefits of a temporal encoding circuit and spatial bus-invert coding techniques to simultaneously eliminate opposite transitions on adjacent wires and reduce the number of self-transitions and coupling-transitions. In the design process of applying encoding techniques for reduced bus delay and energy, we present a repeater insertion design methodology to determine the repeater size and inter-repeater bus length, which minimizes the total bus energy dissipation while satisfying target delay and slew-rate constraints. This methodology is employed to obtain optimal energy versus delay trade-offs under slew-rate constraints for various encoding techniques. 展开更多
关键词 on-chip buses DELAY energy ENCODING REPEATERS
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半导体生产线建立过程及问题处理
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作者 岳云 《世界电子元器件》 2002年第7期64-66,共3页
建一个新工厂意味着时间、金钱和公司资源上的巨大投入。整个公司的成功与否有可能取决于这个新工厂的投资回报率(ROI)。要实现ROI的最大化,需在多个因素之间进行权衡,从最初的工厂设计到后来的生产上量阶段。
关键词 投资回报率 工厂建设 工厂规划 生产上量 半导体生产线
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Determination of Five Metallic Elements in Guoshangye from Guizhou by Microwave Digestion-flame Atomic Absorption Spectrometry
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作者 马四补 王绍辉 +2 位作者 刘同祥 李开斌 陈维 《Agricultural Science & Technology》 CAS 2016年第2期262-264,共3页
In the study, the contents of 5 trace elements including Fe, Cu, Mg, Mn and Ca were directly analyzed by flame atomic absorption spectroscopy in Gu- oshangye. The sample was subjected to microwave digestion with HNO3 ... In the study, the contents of 5 trace elements including Fe, Cu, Mg, Mn and Ca were directly analyzed by flame atomic absorption spectroscopy in Gu- oshangye. The sample was subjected to microwave digestion with HNO3 and H2O2, and detected by the standard curve method. The results showed that Guoshangye contained abundant trace elements which rates of these trace elements were in the curacy and satisfactory. were necessary for human. The recovery range of 96%-103%. The method is ac- 展开更多
关键词 Trace elements Guoshangye Flame atomic absorption spectroscopy
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Genetic Analysis of Root Growth in Rice Seedlings Under Different Water Supply Conditions 被引量:7
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作者 张卫萍 吴平 +1 位作者 沈晓莹 吴运荣 《Acta Botanica Sinica》 CSCD 2001年第10期1024-1030,共7页
To understand the genetic background of root growth of rice ( Oryza sativa L.) seedlings under different water supply conditions, quantitative trait loci (QTLs) and epistatic effect on seminal root length, maximum adv... To understand the genetic background of root growth of rice ( Oryza sativa L.) seedlings under different water supply conditions, quantitative trait loci (QTLs) and epistatic effect on seminal root length, maximum adventitious root length, adventitious root number, total root dry weight and ratio of root to shoot were detected using molecular map including 103 restriction fragment length polymorphism (RFLP) markers and 104 amplified fragment length polymorphism (AFLP) markers mapped on a recombinant inbred line (RIL) population with 150 lines derived from a cross between an lowland rice IR1552 and an upland rice Azucena in both solution culture (lowland condition) and paper culture (upland condition). Six QTLs and twenty-two pairs of epistatic loci for the four parameters were detected. Three QTLs detected for maximum adventitious root length in solution culture (MARLS), total root dry weight in both solution culture and paper culture (TRDWS and TRDWP) accounted for about 20%, 23% and 13% of the total variations, respectively. Only epistatic loci were found for maximum adventitious root length and adventitious root number in paper culture (MARLP and ARNP), and for ratio of root to shoot in both paper and solution culture (R/SP and R/SS), which accounted for about 12%-61% of the total variations in the parameters, respectively. No identical QTL or epistatic loci were found for the parameters in both solution and paper culture. The results indicate that there is a different genetic system responsible to root growth of rice seedlings under lowland and upland conditions and epistasis might be the major genetic basis for MARLP, ARNP, R/SP and R/SS. 展开更多
关键词 RICE root growth solution culture paper culture quantitative trait loci EPISTASIS
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Comparison of Soil Respiration in Two Grass-Dominated Communitiesin the Xil in River Basin: Correlations and Controls 被引量:5
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作者 张焱 李凌浩 +5 位作者 王艳芬 唐芳 陈全胜 杨晶 袁志友 董云社 《Acta Botanica Sinica》 CSCD 2003年第9期1024-1029,共6页
A comparative study of soil respiration was conducted between in a semi-arid steppe community and in a wet meadow community in the Xilin River Basin of Nei Mongol. The seasonal pattern, the climatic controls, and the ... A comparative study of soil respiration was conducted between in a semi-arid steppe community and in a wet meadow community in the Xilin River Basin of Nei Mongol. The seasonal pattern, the climatic controls, and the correlations of soil respiration with plant biomass components, were examined for each community. The main results are reported as follows: (1) The seasonal changes in soil respiration in the two communities had similar dynamic patterns (both being of two peaks), ranging from 312.8 to 1738.9 mg C(.)m(-2).s(-1) and from 354.6 to 2235.6 Mg C.m(-2).s(-1) in the growing season for the steppe plot and the meadow plot respectively. The soil respiration rate of the meadow plot was distinctly higher than that of the steppe plot, with the daily averages being 1349.6 mg C-m(-2).s(-1) and 785.9 mg C-m(-2).s(-1) respectively. (2) The correlation between soil respiration rate and soil moisture was much more significant than with temperature for the steppe community, and being on the contrary for the meadow community, reflecting the different effects of the two climatic factors in different habitats. Based on these regressive relations, the total CO2 efflux rate in the growing season in 2001 was estimated as 142.4 g C/m(2) in the steppe plot, and 236.1 g C/m(2) in the meadow plot. (3) There was no evident relation between the total canopy biomass and CO2 evolution rate, but a significant power function relation between the live canopy biomass and CO2 evolution rate in the meadow plot was detected. In the steppe plot, there existed only a weak relation between soil respiration and either live or total canopy biomass. 展开更多
关键词 soil respiration temperature soil moisture canopy biomass STEPPE MEADOW
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Study on the Degradation Trend of Ryegrass-White Clover Artificial Grassland 被引量:12
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作者 张建波 李相林 +4 位作者 万里强 陈瑞祥 赵相勇 陈伟 陈国南 《Agricultural Science & Technology》 CAS 2009年第1期26-28,88,共4页
[Objective] The study aimed to explore the degradation law and trend of artificial grassland. [Method] Taking the ryegrass (Lolium perenne) - white clover ( Trifolium repens) artificial grassland in Maiping Townsh... [Objective] The study aimed to explore the degradation law and trend of artificial grassland. [Method] Taking the ryegrass (Lolium perenne) - white clover ( Trifolium repens) artificial grassland in Maiping Township, Guizhou Province as the research object, the grassland vegetation of 40 quadrate from different areas (area around the sheep shed, hilltop, hillside, flatland at the foot of the hill) were analyzed by comparing the dominance and richness index. [ Result] Degradation of different degrees appeared in various areas of this artificial grassland. To be specific, the degradation of grassland around the sheep shed was not serious for less consumption by the sheep; however, the areas on the hilltop and hillside degenerated to the grassland types of dallis grass ( Paspalum dilatatum Poir. ) -Indian lovegrass ( Eragrostis pilosa) and dallis grass - cogongrass [ Imperata cylindrica ( Linn. ) Beauv. ], respectively, and the area at the foot of the hill degenerated to the grassland type dominated by garland chrysanthetnum ( Chrysanthemum coronarium L. ) and knotgrass ( Paspalum distichum L. ). [ Conclusion ] This study provided a basis for grassland improvement as well as the efficient and sustainable utilization of grazing-type artificial grassland in South China. 展开更多
关键词 Ryegrass Lolium perenne) White clover( Trifolium repens) Artificial grassland DEGRADATION
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On the Confidence Limits of Bernoulli Parameter in Any Sequential Case
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作者 陈家鼎 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第1期1-8,共8页
Let x 1,x 2,… be independent identically distributed (i.i.d.) random variables, in which x n=0 or 1 and the probability of {x n=1} is p. Here p is unknown. Let τ be any finite stopping ... Let x 1,x 2,… be independent identically distributed (i.i.d.) random variables, in which x n=0 or 1 and the probability of {x n=1} is p. Here p is unknown. Let τ be any finite stopping time for (x n,n1). For any sequential sample (x 1,x 2,…,x τ ) and γ∈(0,1), we have given an optimal confidence limit of p with confidence level γ . Some related problems are also discussed. 展开更多
关键词 sequential sample Bernoulli parameter lower (upper) confidence limit
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