软土地基地下结构的一个CAD软件

本文介绍地下结构计算机辅助设计软件——UCAD的总体结构、主要功能以及解决的问题。     

Calendar maintenance of arbitrarily structured systems

A semi-Markov model is constructed that describes an arbitrarily structured multicomponent technological system and takes into account its calendar maintenance. Using an aggregation algorithm, approximate values of stationary reliability characteristics and an optimal term of maintenance work are determined for the system. __________ Translated from Kibernetika i Sistemnyi Analiz, No. 2, pp. 69–86, March–April 2006.     

杜84断块超稠油开发中后期稳产对策研究

对杜84断块超稠油生产中后期暴露的主要矛盾，即随着轮次升高，周期吞吐效果变差，井下技术状况日益变差。油层动用不均，汽窜加剧等问题进行了分析。并提出了相应的稳产对策-实施多井整体吞吐，大修复产，调剖等措施。现场应用证明，这些措施基本能够确保杜84断块超稠油中后期的稳产。     

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。     

双马来酰亚胺树脂体系的固化反应研究

利用ＤＳＣ及原位ＦＴＩＲ技术研究了双马来酰亚妥树脂体系的固化反应，获得了在固化反应过程中各组分的转化率与时间的关系，结合热分析数据，确立了最佳固化工艺。     

The combined effects of curing and environmental exposure on fracture properties of woven carbon/epoxy laminates

This paper concerns a study of the combined effects of curing conditions and environmental exposure on the ultimate properties of two commercial woven carbon/epoxy laminates. Curing parameters (heating rate and applied pressure) were varied so as to obtain six different conditions for each material. Moisture saturation was also achieved by exposing some of the cured samples to environmental conditions of 70°C and 95% relative humidity. Four different tests (tensile, impact, Mode I and Mode II interlaminar fracture resistance) were therefore performed, and the results obtained on the different materials before and after moisture saturation compared. Neither curing pressure nor heating rate nor moisture absorption were observed to have any practical effect on tensile and impact properties. On the contrary, one noticeable effect was the interlaminar fracture resistance of the laminates. The results are discussed and interpreted in terms of damage formation and stress intensification mechanisms.     

小麦、玉米控制灌溉技术研究

198 6～ 1998年 ,在山东省的 3个灌溉试验站 ,对冬小麦、秋玉米进行了控制灌溉试验 ,对农作物的多个生育阶段 ,按高产的要求 ,分别给予适时、适量的灌溉水 ,来控制作物不同生长期的根层土壤含水量 ,从而控制作物不同生长期根系对水分的吸收 ,培植农作物的“丰产群体结构”和与之相适应的“高产理想株型” ,适当降低无效的蒸腾量 ,使农作物能在高产的基础上再增产 .该项控制灌溉技术获得了明显的节水、增产效果 ,灌溉水的生产效率超过了 10kg/m3,产量超过了 8t/hm2 .     

地理环境与先秦南北饮食文化

先秦时期是我国饮食文化的形成时期，受地理环境的强烈影响，逐渐形成了以秦岭-淮河一线为界的南北两个主要的饮食文化区域：黄河中下游地区为中心的北方饮食文化区，是以旱地粮食作物黍、稷、粟等为主食，陆地动物为辅食，烧、烤、炸为主要烹饪方法的北方饮食风味；长江中下游地区为中心的南方饮食文化区，是以水田粮食作物稻米为主食，陆地动物和水产动植物为辅食，蒸、炖、煎为主要烹饪方法的南方饮食风味。     

A New Variable Diffusion Drying Model for the Second Falling Rate Period of Paddy Dried in a Rapid Bin Dryer

The objectives of this article is to propose a new drying model for the second falling rate period known as the variable diffusion controlled period that follows after the first falling rate period and to propose a new method to determine the second critical moisture content that separates these two periods. Experimental work on paddy drying at minimum fluidization velocity was carried out in a rapid bin dryer. The effects of operating temperatures (60-120°C) and bed depths (2-6 cm) on the paddy drying characteristics were investigated. It was found that the normalized drying rate of paddy was proportional to the normalized moisture content in the first falling rate period but in the second falling rate period, the normalized drying rate of the material varies exponentially with the normalized moisture content. The different relationship between the normalized drying rate and the normalized moisture content in the first and second falling rate periods indicate that two different mechanism of moisture transport are at work. The new exponential model of the second falling rate period and the linear model of the first falling rate period were found to fit the experimental data very well. Derivation from variable diffusion equation shows that the linear model is the result of constant diffusion coefficient whereas the new exponential model is the result of linear diffusion coefficient. This also implies that the first falling rate period is a constant diffusion controlled period and the second falling rate period is a variable diffusion controlled period. In addition, drying kinetics data of a drying process that fits the exponential model over a very slow drying period will show that the drying process is under the effect of a linear diffusion coefficient. It was also found that the proposed new method to determine the second critical moisture content that distinguishes between the first and second falling rate periods by using a sudden change in the value of the drying rate gradient to a much lower value at that point is more rigorous and yet simpler than the method of determining the specific location of the receding drying boundary since it is based on the behavior of the actual drying kinetic data.     

水电站施工期水土流失预测

水电站建设的水土流失问题主要体现在施工期和运行期，并以施工期的影响较为突出．如不采取必要的减免措施，将会对周围生态环境造成无法挽回的损失。本文阐述了水电站建设水土流失的几种常用的预测方法，对水土流失量进行预测，并结合具体工程实例对水电站建设过程中新增水土流失量进行了预测。