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排序方式: 共有7393条查询结果,搜索用时 765 毫秒
31.
《Drying Technology》2007,25(10):1621-1632
A study was performed to determine the drying characteristics and quality of barley grain dried in a laboratory scale spouted-bed dryer at 30, 35, 40, and 45°C and an inlet air velocity of 23 m/s-1, and in an IR-convection dryer under an infrared radiation intensity of 0.048, 0.061, 0.073, and 0.107 W cm-2 at an air velocity of 0.5 m/s-1. The results show that the first, relatively short, phase of a sharp decrease in the drying rate was followed by the phase of a slow decrease. The time of barley drying depended on temperature of inlet air in a spouted-bed dryer and on radiation intensities in an IR-convection dryer. Barley drying at 45°C in a spouted-bed dryer was accompanied by the lowest total energy consumption. The average specific energy consumption was lower and the average efficiency of drying was higher for drying in a spouted-bed dryer. The effective diffusivities were in the range 2.20-4.52 × 10-11 m2 s-1 and 3.04-4.79 × 10-11 m2/s-1 for barley dried in a spouted-bed and in an IR-convection dryer, respectively. There were no significant differences in kernel germination energy and capacity between the two drying methods tested. 相似文献
32.
利用地震属性资料解释河道 总被引:2,自引:0,他引:2
地下某一层段的地震属性特征通常揭示了一些地质或沉积特征,如礁体、河道、三角洲、地台等。文中采用分层段切片解释方法,对塔河油田外围兰尕三维资料进行切片分析,在三叠系上油组地层中的振幅属性平面图上分布有南北方向的河道,地震解释剖面及钻井资料也得到证实。研究中发现,分析时窗的大小决定了振幅属性在河道处能量的强弱,根据河道的分布可以追踪河道砂岩体及其分布范围,为研究有利储层提供了可靠依据。 相似文献
33.
Abstract. While a large body of research exists on the development and implementation of software, organizations are increasingly acquiring enterprise software packages [e.g. enterprise resource planning (ERP) systems] instead of custom developing their own software applications. To be competitive in the marketplace, software package development firms must manage the three-pronged trade-off between cost, quality and functionality. Surprisingly, prior research has made little attempt to investigate the characteristics of packaged software that influence management information system (MIS) managers' likelihood of recommending purchase. As a result, both the criteria by which MIS managers evaluate prospective packaged systems and the attributes that lead to commercially competitive ERP software products are poorly understood. This paper examines this understudied issue through a conjoint study. We focus on ERP systems, which are among the largest and most complex packaged systems that are purchased by organizations. In a conjoint study, 1008 evaluation decisions based on hypothetical ERP software package profiles were completed by managers in 126 organizations. The study represents the first empirical investigation of the relative importance that managers ascribe to various factors that are believed to be important in evaluating packaged software. The results provide important insights for both organizations that acquire such systems and those that develop them. The results show that functionality, reliability, cost, ease of use and ease of customization are judged to be important criteria, while ease of implementation and vendor reputation were not found to be significant. Functionality and reliability were found to be the most heavily weighted factors. We conclude the paper with a detailed discussion of the results and their implications for software acquisition and development practice. 相似文献
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Teresa A Morrison J Raymond Kessler Ronald D Hatfield Dwayne R Buxton 《Journal of the science of food and agriculture》1994,65(2):133-139
To ascertain the temporal relationships of phcnylpropanoid and lignin pathway enzymes, phenylalanine ammonia-lyase (PAL) and cinnamyl alcohol- NADPH dehydrogenase(CAD), with lignin concentration, PAL and CAD activities and lignin concentrations were assessed during progressive development of the 10th internode in maize (Zea mays L). Enzyme activities were quantified and lignin concentrations were determined by the detergent system of fiber fractiona- tion from lower, middle, and upper sections of the elongating internode harvested 3, 5, 7, 9, 11, 13, and 15 days after the internode had reached 10 mm in length. Over 15 days, a coordinated, sequential, and basipetal pattern of enzyme activities and lignin accumulation evolved through the internode, spanning the stages of rapid elongation, cellular differentiation, and secondary cell wall formation. PAL activity was initiated first, rising to peak activity in elongating tissue, and falling basipetally in tissues as they matured. CAD activity rose in fully elongated, maturing internode tissue where PAL activity was waning following its peak activity. Lignin accumulated in tissues with high CAD activity. CAD activity and lignin deposition patterns were similar: simultaneously increasing in activity and deposition over time while activity and deposition also shifting basipetally through the internode, keeping pace with secondary cell wall formation. Lignin concentration correlated significantly with CAD, but not with PAL. 相似文献
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38.
黄亚斌 《石油化工管理干部学院学报》2003,(1):9-11
多数国有大中型企业实行公司化改制后经营状况依然不佳,直接原因在于公司的治理存在严重的问题和缺陷。规范的公司治理结构能有效缓解代理问题。国有企业的产权残缺性,使公司治理结构中的直接监督和间接监督等有效手段不能充分发挥。通过股权结构的分散化调整,充分发挥非国有股权所有者的作用,建立有效的公司治理结构。 相似文献
39.
股票期权的会计处理方法研究 总被引:2,自引:0,他引:2
经理人股票期权是对管理者实行的长期激励制度,由于我国制度上的缺陷,目前在我国没有统一的处理方法,本文讨论的主要是在国际上股票期权的确认、计量以及在会计报表中披露的会计方法。 相似文献
40.
松辽流域初始水权分配实践与探索 总被引:4,自引:1,他引:3
根据松辽流域用水现状和需水预测,流域水资源承载能力将成为流域经济社会可持续发展的关键制约因素.节水型社会建设是解决这一问题的战略举措.水权制度建设和水市场建立是水资源管理适应市场经济的正确选择.面对松辽流域水资源管理的实际情况,流域初始用水权分配是实现战略举措的一项基础工作,也是水权制度建设和水市场建立的起步工作.结合松辽流域的具体情况,松辽委适时组织开展了流域初始用水权分配专题研究,并在霍林河与大凌河流域进行了初始用水权分配的实践探索. 相似文献