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1.
龚必铺 《四川环境》1993,12(1):39-40
本文通过对烟气测试中流速计算公式的比较分析,结合实际监测数据处理,认为烟气流速计算中,使用通用公式与简化公式的误差,虽然与Rs和Bs有关,但主要误差来源于Bs。而Rs不必用精密仪器测出烟气中各组份后求算。只要用简易仪器测得烟气中的Xo2和Xsw的百分含量,即可求出Rs近似值,用于烟气流速计算。  相似文献   

2.
ABSTRACT: The effects of the selections of plotting position formulae and class division schemes on goodness of fit tests are investigated for the extreme-value type-1 distribution using annual flood and annual maximum daily rainfall data. It was found that the plotting position formulae have a minor influence on the tests which involve their use, while the class division schemes may have a pronounced effect on the X2-test. The study also recommended the maximum likelihood method for fitting purposes and a new test which is independent of the afore-mentioned selections for judging the goodness of fit.  相似文献   

3.
喷气式飞机设备可靠性综合试验剖面设计   总被引:1,自引:0,他引:1  
袁宏杰  党炜  杨贵超 《环境技术》2004,22(6):4-6,14
可靠性试验剖面是保证可靠性试验结果客观有效的重要条件。但GJB899中关于制定可靠性试验剖面的一些规定可操作性不强,无法满足实际工作的需要。为解决这些问题,研究了GJB899的有关内容,运用数学和空气动力学知识,对其中某些内容进行了优化和细化,总结了计算温度应力和动压的相关公式,以及温度应力加权的方法。使试验剖面更为合理。  相似文献   

4.
As a result of the current decline of oil prices, exploration decisions are more carefully analysed than ever before. At the same time various governments have introduced incentives to reinvest in exploration and development in order to maintain or increase activity. As a result, most exploration decisions are now being analysed as "incremental investments". This has the effect of "trapping" investments in areas where profits are currently being made. This in turn creates serious problems for those developing countries which would like to attract exploration. The paper analyses issues related to sliding scale formulae based on the ROR, and the economic impact of the size of the area to which fiscal terms apply.  相似文献   

5.
非离子氨的换算工作在我国才刚开始,由于存在不少问题,给标准执行中带来一定困难。本文从水化学实际出发,根据化学平衡原理,导出了水体中非离子氨分布系数(或百分率)的计算公式及其浓度的换算公式。既引入了水温,pH,还引入了离子强度,且介绍了两个水中离子强度的经验计算公式,使计算手续大为简化。本文提出的计算公式,不仅能满足淡水水体的需要,也能满足其它水体,如海水的需要。  相似文献   

6.
ABSTRACT: The income redistribution effects of waste water treatment grants are estimated for each state participating in five federal programs. Both gross and net effects per state and per capita are discussed. The impact of the tax structure used to finance such grants and the grant formulae are investigated.  相似文献   

7.
In this paper, the power output of the cycle is taken as objective for performance optimization of an irreversible regenerated closed Brayton cycle coupled to constant-temperature thermal energy reservoirs in the viewpoint of finite time thermodynamics (FTT) or entropy generation minimization (EGM). The analytical formulae about the relations between power output and pressure ratio are derived with the heat resistance losses in the hot- and cold-side heat exchangers and the regenerator, the irreversible compression and expansion losses in the compressor and turbine, and the pressure drop loss in the piping. The maximum power output optimization is performed by searching the optimum heat conductance distribution corresponding to the optimum power output among the hot- and cold-side heat exchangers and the regenerator for the fixed total heat exchanger inventory. The influence of some design parameters, including the temperature ratio of the heat reservoirs, the total heat exchanger inventory, the efficiencies of the compressor and the turbine, and the pressure recovery coefficient, on the optimum heat conductance distribution and the maximum power output are provided. The power plant design with optimization leads to smaller size including the compressor, turbine, and the hot- and cold-side heat exchangers and the regenerator.  相似文献   

8.
ABSTRACT: A methodology has been developed to predict the responses of a range of water supply sources in Wales to global warming scenarios. Hydrologically effective rainfall is predicted from temperature and precipitation for each season based on site specific formulae developed using the Meteorological Office Rainfall and Evaporation Calculation System (MORECS) and UK Surface Water Archive databases. Comparisons are then made between the effects predicted for the scenarios established from equilibrium simulations and the new Hadley Centre High Resolution Model (UKHI) transient mode results. Though very different, both suggest increased stress on water resources late in the hydrological year.  相似文献   

9.
This paper reviews selected research on classroom and school environments, using a framework that views schools from three perspectives—as places for learning, as places for socialization and as places for psychological development. Studies are included that deal with the impact of noise and classroom design on learning; the relationship between seating position, achievement and status; spatial cognition; the classroom environment and sex role stereotyping; privacy; and density. The need for classrooms to enhance children's feelings of competence, security and self-esteem is also stressed. The goal of the paper is to point out ways in which environmental psychologists can contribute to the improvement of the educational system and to the quality of life in schools.  相似文献   

10.
吴力斌 《四川环境》1993,12(1):70-71
本文荟萃了荷兰、美国、德国、法国许多学者对厌氧颗粒污泥培养的研究,强调了颗粒化的机理仍是一个较为复杂而尚存在许多未知数的领域,并介绍了颗粒污泥的贮存。  相似文献   

11.
周仕强 《四川环境》1991,10(1):34-39
本文对小型造纸厂的碱回收在技术上和经济上的可行性进行了分析,作出了当前是中、小型造纸厂搞碱回收的有利时机的初步评价。  相似文献   

12.
The successful management of atmospheric pollution is best achieved when the benefits of controls can be clearly demonstrated to those who the controls affect. There is a need to demonstrate to a population that change will benefit the social and biophysical aspects of that population’s environment as a whole. This paper suggests that policy-makers need to demonstrate clearly the advantages of a change in behaviour for the local environment while concurrently minimising the life-style costs of the people whose co-operation is needed to bring that change about. This requires an improved understanding of the activities affected and the message and media by which environmental benefits can be communicated in the light of that understanding.Using the example of tropospheric ozone, this paper argues that air-quality management requires close regional co-ordination which can facilitate the establishment and implementation of local policy options. The ability of the UK National Air Quality Strategy to achieve this in its present form is discussed and the existence of a strategic gap between the current approach to air-quality management and the major issues surrounding air quality considered.  相似文献   

13.
孙昌华 《四川环境》1993,12(4):30-32
本文叙述了绵阳城区的环境质量现状。根据绵阳历史及发展,到2010年要建成为100万人口的大城市,提出未来的绵阳城区既是一个开放型、式功能、综合性的现代化中心城市,又应是一个环境优美、整齐清洁、繁荣兴旺、高度文明的现代化城市。必须高度重视环境保护工作,建议采取包括环境规划、抓好环境建设及环境管理等措施。  相似文献   

14.
CODcr快速测试法的探索   总被引:1,自引:0,他引:1  
本文探索了CODcr的快速测试法,结果表明,采用简易的火焰加热消化法测定CODcr是可行的。该法所用的仪器设备简单;操作方便,快速,回收率高,特别适用于现场及简易实验室。  相似文献   

15.
ABSTRACT: This paper describes a preliminary investigation of the hydropower potential at the existing Conemaugh Dam, a U.S. Army Corps of Engineers project located in the Kiskiminetas River Basin, Pennsylvania. The objective of the study was to determine the most cost effective layout of power production facilities for each of four possible installed capacities. Based on preliminary cost estimates and monthly power production computations, a layout using standard tube turbines in a powerhouse constructed on the face of the emergency spillway would produce the cheapest energy at a capacity of 8 to 10 megawatts (MW).  相似文献   

16.
ABSTRACT. Flood detention reservoir design is a common problem encountered by engineers and others involved with water resources problems. This paper presents a method by which the volume of flood storage required for a single reservoir or a series of reservoirs may be estimated without using numeric flood-routing techniques. The proposed procedure requires a minimum of computations and is most applicable to preliminary design situations where a high degree of accuracy is not required.  相似文献   

17.
彭良燕 《四川环境》2000,19(3):76-78
近年来,全民水库的网箱养鱼发展很快,1997年12月我市全民水库发生了罕见的死鱼事件,严重影响了市、区的生产、生活供水,曾引起省、市、区领导的高度重视。本文在收集大量资料的基础上,分析讨论了全民水库死鱼的原因。  相似文献   

18.
张仕友 《四川环境》1996,15(4):51-52
本文对人类最清洁的能源核聚变能作了简单的介绍。  相似文献   

19.
Small towns are an important part of the rural settlement fabric in the United States, but there is very little substantive research into their capacity to survive or their intrinsic importance. However, recently there has been increasing interest shown by social scientists in these problems. This paper looks at features of this research from the point of view of the population and economic structure of small towns. It concludes by arguing that the problems of small towns are not indigenous to the towns, and calls for a comprehensive national urban policy.  相似文献   

20.
白腐真菌生化降解TNT的研究   总被引:4,自引:1,他引:3  
本文在建立微生物降解废水中有机污染物的中间反应模型的基础上,推导出TNT废水的COD降解参数方程,并与实测值比较,基本吻合,为以后深入研究提供理论指导。  相似文献   

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