水库发电运行的计算机仿真

介绍了用VB语言编写的一个简便、实用的适合洞坪水库发电运行的计算机仿真程序.     

矿山空压机设备的经济运行

空压机设备是煤矿耗电量较大的设备之一。如何提高空压机设备的运行效率,对节约电能和降低生产成本有着非常重要的意义。文章论述了提高空压机运行效率的措施及方法,提出了合理化建议。     

Water and Radiation Effect on Sweet Sorghum Productivity

Suitability of sweet sorghum in Greece, where irrigation supply during crop development is limited as rainfall is scarce and evapotranspiration loss is high, is examined in relation with radiation availability. A two-year field experiment was conducted, in central Greece, imposing four soil water regimes via different irrigation treatments: (1) Highly irrigated, (2) Highly irrigated till anthesis when irrigation stopped, (3) Medium irrigated, and (4) Low irrigated. It was found that above-ground dry biomass production from non-water-stressed sweet sorghum plants suggests a high productivity potential among C₄ crops. Under water shortage, radiation use efficiency may be significantly lower. Radiation use efficiency seems to be linearly related to water consumption. Stressed plants (probably except severely stressed) seem to use available water more efficiently than unstressed plants. The slope of the line relating dry matter produced and water evapotranspired increases the sooner the stress is sensed. Yield reduction resulting from post-anthesis irrigation stopage is very little. High water use efficiency values tend to be related with low radiation use efficiency values.     

稠油井注汽系统的热效率分析

建立了热采注汽系统热效率的计算模型。根据XX油田数据计算了2个注汽系统的热效率。提出了提高注汽系统热效率的三项措施：（1）降低锅炉的过剩空气系数；（2）按最大允许热损失设计地面输汽管线的保温层厚度；（3）使用视导热系数小的隔热油管，按箍增加隔热结构，防止热封隔器的泄漏等。     

童氏标准公式的校正及应用

在童标准公式中引入校正系数，提出了童氏校正公式，应用该校正公式可对水驱断块油田以及标定采收集较低的油田进行早期含水率预测和采收率预测，应用实例表明，与实际生产数据对比，校正公式计算值比标准公式计算值的误差小得多。     

利用大流量液压支架控制顶板事故的发生

通过对工作面端面冒顶原因及支护系统的分析得出，加大液压支架的流量可以加快移架速度，降低冒顶事故率，提高生产效率。     

The smooth fractionator

A modification of the general fractionator sampling technique called the smooth fractionator is presented. It may be used in almost every situation in which sampling is performed from distinct items that are uniquely defined, often they are physically separated items or clusters like pieces, blocks, slabs, sections, etc. To each item is associated a ‘guesstimate’ or an associated variable with a more‐or‐less close – and possibly biased ? relationship to the content of the item. The smooth fractionator is systematic sampling among the items arranged according to the guesstimates in a unique, symmetric sequence with one peak and minimal jumps. The smooth fractionator is both very simple to implement and so efficient that it should probably always be used unless the natural sequence of the sampling items is equally smooth. So far, there is no theory for the prediction of the efficiency of smooth fractionator designs in general, and their properties are therefore illustrated with a range of real and simulated examples. At the cost of a slightly more elaborate sampling scheme, it is, however, always possible to obtain an unbiased estimate of the real precision and of some of the variance components. The only real practical problem for always obtaining a high precision with the smooth fractionator is specimen inhomogeneity, but that is detectable at almost no extra cost. With careful designs and for sample sizes of about 10, the sampling variation for the primary, smooth fractionator sampling step may in practice often be small enough to be ignored.     

提高特高含水期油藏采收率的方法及应用效果

针对胜索油田二区9-10单元的层间非均质和平面非均质性，运用水动力学方法，采用周期注水及增压注水改善单元的水驱油效果。经过6a的实施，单元的开发形势趋好，单元采收率提高9.62%，增加可采储量341.5kt，对同类型非均质性油藏改善水驱油效果，提高最终采收率具有借鉴意义。     

通过薄弱环节分析提高织造效率

通过改善织物质量和提高织造效率可对企业的经济效益做出重要贡献。借助于一个有针对性的企业分析能确定企业现状并在此基础上得出改进的措施。这些任务可由组成“纺织技术顾问团（TTC）”的有经验的工程师们完成。     

Modeling of the bulk free radical polymerization up to high conversion—three stage polymerization model. II. Number-average molecular weight and apparent initiator efficiency

The equations for predicting the number-average molecular weight are derived on the basis of the three stage polymerization model (TSPM) in this paper. By applying the equations, a plotting approach is proposed to determine the apparent initiator efficiency defined as f[(α_td+1)/2] and the constant of chain transfer to monomer, where f is the initiator efficiency and α_td denotes the fraction of the termination rate constants by disproportionation. Using the approach to plot the experimental data in the literature, it is found that the chain transfer to monomer can be neglected for both methylmethacrylate (MMA) and styrene (St) polymerizations, but it can exert a significant effect on ethylmethacrylate (EMA) polymerization. In addition, the apparent initiator efficiency is found to be independent of reaction temperature and initiator concentration at each stage. The values of f[(α_td+1)/2] at gel effect stage are slightly reduced as compared with that at low conversion stage for MMA and EMA polymerizations. However, it decreases significantly at gel effect stage for St polymerization. Using the equations derived and the apparent initiator efficiencies obtained from TSPM plots, the number-average molecular weights at different conversions can be predicted. Comparisons show that the agreement between predictions and experimental data is satisfactory.