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31.
分析了当前家装存在的破坏结构,一味追求奢华,施工质量差等种种误区,提出了搞好家庭装修的关键环节,对促进家装行业健康发展有积极的意义。 相似文献
32.
Using meta-analysis, randomized experiments in education that either clearly did or clearly did not experience student attrition were examined for the baseline comparability of groups. Results from 35 studies suggested that after attrition, the observed measures of baseline comparability of groups did not differ more than would be expected given sampling error. The degree of either overall or differential attrition did not relate to baseline comparability, a finding that held under sensitivity analyses. Also, both overall and differential attrition rates were unrelated to posttest effect sizes. All of these analyses, however, lacked sufficient statistical power to detect small but potentially meaningful effects. Results suggest caution is warranted when applying quality scales and other blanket rules pertaining to attrition that are meant to either serve as inclusion-exclusion criteria or in scoring study quality. Much greater attention is needed to both the reporting of attrition in primary studies and to the development of conceptual and empirical models of the attrition process. These developments would aid further investigation of the relation between attrition and study outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
33.
Kevin Yale Teichman 《Indoor air》1994,4(3):202-211
Deciding between the different policy approaches available for reducing human exposures to indoor pollutants is an exceptionally complex task. These options can range from waiting until more definitive information is available to enacting regulatory standards, with many variations in between. This paper presents some of the factors policy-makers must consider in establishing indoor air quality policies, and the role researchers should play in ensuring that indoor air policies are based on the best available scientific information. 相似文献
34.
从油田现场反应的情况出发,对调整井固井,尾管固井,大位移井套管固井和其他固井的质量问题进行了分析,针对各种问题产生的原因,提出了相应换解决办法。 相似文献
35.
Kwang Soo Lee In Soo Park & Dong Sun Lee 《International Journal of Food Science & Technology》1996,31(1):7-13
The aim of this study was to design a modified atmosphere package for a mixed vegetable salad consisting of 75 g of cut carrot, 55 g of cut cucumber, 20 g of sliced garlic and 50 g of whole green pepper. Respiration data of all the components were combined with film permeability data to predict package atmospheres and design optimal packages for experimental testing for improved shelf-life of the produce. The optimal package avoided minimum O2 and maximum CO2 tolerance limits, and chilling injury temperatures for any component. A pouch form package made of 27 mm low density polyethylene developed a modified atmosphere of 2.0–2.1% O2 and 5.5–5.7% CO2 , which was beneficial for all components and provided better quality retention than other test packages. 相似文献
36.
With this volume, the 47-year old Canadian Journal of Psychology takes a new name and makes a renewed commitment. In retitling the journal the Canadian Journal of Experimental Psychology, the intention is to reflect more clearly what has always been the major goal of the journal--to publish the best new research in experimental psychology, both Canadian and international, in both French and English. I am honoured to become the tenth editor of the major journal for experimental psychology in Canada. CJP has served the field very well; my primary goal is to ensure that CJEP continues to do so. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
37.
探讨了过滤器孔径对6063铝合金铸锭组织和性能的影响规律。在此基础上指出,在过滤工艺恰当时,不仅可以减少铸锭中的夹杂物,而且可以有效地防止裂纹、羽毛晶等连续铸锭中的常见缺陷。 相似文献
38.
通过具体工程实践,在吸收现有滑模工艺技术的基础上,对平台扭转、中心垂直度控制等关键工艺进行创新,为提高工程质量提供技术保证,达到了创省级优质工程的效果。 相似文献
39.
Vibro-fluidized beds are widely used in drying sticky powders and agglomerated materials as milk powder. Using a vibro-fluidized laboratory scale dryer, this work is aiming at analyzing preliminarily the effect of its operational variables on the drying kinetics and characteristics of whole milk powder. The full-factorial design technique with three replications at the central point has been employed to generate data and correlations to quantify the effect of inlet air temperature, air flow rate, and vibration bed amplitude on the drying curves and the milk powder properties related to its faster reconstitution in water (as tapped density, Hausner cohesion ratio, agglomerate size distribution, and internal pore concentration). Results obtained are analyzed and discussed to identify the adequate operation condition for final drying whole milk powder in vibro-fluidized beds, assuring a high product quality. 相似文献
40.
Baak K. Taeli 《Lakes & Reservoirs: Research and Management》2006,11(3):149-168
Lake Mogan, located in the steppes of central Anatolia, is a vital Turkish ecological system, in terms of its water resources, flora and fauna. The lake also is a unique recreational area for Ankara, the capital of Turkey. However, the lake is currently threatened by severe pollution, being under the risk of serious degradation because of (i) uncontrolled urbanization; (ii) point and non‐point source pollution; (iii) inefficient sewerage systems; (iv) sediment transportation and pollution via influent creeks to the lake; (v) uncontrolled soil erosion in its drainage basin; (vi) inappropriate flood control measures; and (vii) severe degradation of the natural wetlands within its drainage basin. This study evaluates the influence of its influent creeks on the water quality of Lake Mogan, mainly because the creeks are believed to be responsible for the major pollutant load reaching the lake, and because the extensive database documenting this situation has not previously been critically evaluated. Accordingly, this study reviews (i) change in the water quality of Lake Mogan between 1993 and 2002; (ii) the water quality classification of the major influent creeks feeding Lake Mogan; and (iii) the influence of the influent creeks on the water quality of the lake between 1993 and 2004. 相似文献