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681.
682.
行为矫正法在建筑火灾安全中的应用研究 总被引:4,自引:0,他引:4
随着建筑物防火性能化的发展以及人行为机理的复杂性 ,要求应用更多的学科研究建筑物火灾中人的行为与安全疏散理论。行为矫正学是一门基于过去经验与实验研究的学科 ,笔者在阐述其基本原理和特点的基础上 ,提出了在灾害事故中应用此方法的模式 ,然后结合高层建筑物火灾疏散的特点 ,对高层居民建筑物发生火灾时 ,如何矫正人的一些不正确F行为和提高火灾安全进行了探讨。分析了矫正模式的功能和干预的措施。 相似文献
683.
Kenneth O. Kauffman 《Journal of the American Water Resources Association》1979,15(2):387-395
ABSTRACT: In many of the limited water resource areas of the western United States most water supplies have been put to beneficial uses. Energy, a fast expanding high-priority water use, is making challenging demands for these limited supplies. Can water supplies be stretched, supplemented, or redirected so that present uses can be maintained and energy water needs satisfied? The Bureau of Reclamation is investigating innovative methods of water management, reregulation, and use to meet these demands. Related programs under study include potentials for: development of additional hydroelectric power, installation of low-head turbines in western water courses, utilization of pumped storage and underground storage, use of geo-thermal heat, extension of water supplies through more efficient irrigation systems and practices, and weather modification. 相似文献
684.
Donald M. Bruce 《Journal of Agricultural and Environmental Ethics》2002,15(3):279-289
Future technological developmentsconcerning food, agriculture, and theenvironment face a gulf of social legitimationfrom a skeptical public and media, in the wakeof the crises of BSE, GM food, and foot andmouth disease in the UK (House of Lords, 2000). Keyethical issues were ignored by the bioindustry,regulators, and the Government, leaving alegacy of distrust. The paper examinesagricultural biotechnology in terms of a socialcontract, whose conditions would have to be fulfilled togain acceptance of novel applications. Variouscurrent and future GM applications areevaluated against these conditions. Successwould depend critically on how far a sharedvision can be found with the public. Tore-establish trust, significant changes areidentified in the planning and pursuit ofbiotechnology. 相似文献
685.
阳离子改性粘土对活性染料的脱色作用 总被引:8,自引:0,他引:8
金属离子改性的凹凸棒石和膨润土对水中活性艳红染料K-2BP的吸附脱色作用符合Freundlich吸附等温式并呈现一级反应动力学的特征,吸附的最佳PH范围分别为〈5和〈6,其中以改性凹凸棒石的吸附性能较好,光照检验表明,改性膨润土还具有一定的光化学催化降解作用。 相似文献
686.
Dichloromethane (DCM) is a toxic volatile compound which is found in the ground waters and wastewaters of the pharmaceutical, chemical, textile, metal-working and petroleum industries. DCM inhibits the growth of aquatic organisms, induces cancer in animals and is potentially carcinogenic for humans. This article aims to review existing water treatments for DCM removal, focusing on recent technological advances. Air stripping, adsorption and pervaporation were found to be effective in separating DCM from water with a process efficiency of about 99%, 90% and 80% respectively. Electrocatalysis over Cu-impregnated carbon fiber electrode, photo irradiation over TiO2 and photo-Fenton process led to the complete decomposition of DCM. Aerobic and anaerobic water treatment achieved 99% and 95% removal of DCM respectively. The maximum efficiencies observed for acoustic cavitation, radiolysis and catalytic degradation of CH2Cl2 were 90%, 92% and 99% respectively. Ozonation and persulfate oxidation showed lower DCM degradation efficiencies, not exceeding 20%. Further combination of different water treatment methods will further increase DCM degradation efficiency. 相似文献
687.
Brood sex ratio is dependent on female mating status in polygynous great reed warblers 总被引:2,自引:0,他引:2
Isao Nishiumi 《Behavioral ecology and sociobiology》1998,44(1):9-14
Females capable of adjusting the sex ratio of their offspring should be more fit than females lacking such an ability. In
polygynous birds where breeding success in males is more strongly influenced by body size and/or attractiveness than in females,
females might produce more sons when predicting good conditions or when mating with attractive males. Polygynous great reed
warbler, Acrocephalusarundinaceus, males direct most of their feeding effort to the primary (first-hatching) nest and in these nests increase their feeding
effort in relation to the brood sex ratio (proportion of sons). Therefore, with the expectation of well-nourished sons, we
would predict that females which start breeding first within harems might produce more sons than those which start breeding
later, and in anticipation of sons with good genes, that females mated to polygynous males might produce more sons than females
mated to monogamous males. I took blood samples from hatchlings and determined the sex using DNA markers. The sex ratio of
primary (monogamous and polygynous primary) broods is more male-biased (mean 0.58 males, n = 50) than that of secondary (polygynous secondary and tertiary) broods (mean 0.46, n = 25). Moreover, in the secondary broods with the largest clutch (five eggs), in which offspring are most likely to suffer
food shortage, the sex ratio was distinctively female biased (mean 0.33, n = 10). In the primary broods, sex ratio was correlated to harem size. The results suggest that great reed warbler females
modify the brood sex ratio to produce both well-nourished sons and sons with good genes, but the former effect is probably
stronger than the latter factor.
Received: 11 March 1998 / Accepted after revision: 23 May 1998 相似文献
688.
689.
改性沸石同步深度脱氮除磷的实验研究 总被引:12,自引:4,他引:8
以氯化铝、硫酸镁为活性剂,采取高温活化,对天然沸石进行改性,并通过正交试验优化了改性工艺。以模拟二级出水为研究对象,考察了改性沸石同步去除水样中氮磷的效果及其影响因素,并对不同温度下改性沸石对磷酸盐和氨氮的吸附平衡和吸附热力学,以及脱氮除磷机理进行了探讨。结果表明,15 min后改性沸石脱氮除磷过程基本完成,其pH值范围与实际污水相符,最佳pH值为8;当投加质量浓度为0.8 g/L时,出水中氨氮浓度和总磷浓度均达到景观环境用水水质标准(GB/T 18921-2002)。改性沸石对氨氮和磷酸盐的吸附均符合Langmuir等温吸附方程。热力学参数ΔG0、ΔH0分别为正值和负值,表明该吸附是一个自发的吸热过程。 相似文献
690.
核基因组在细胞质雄性不育中的作用研究:背景与现状 总被引:6,自引:0,他引:6
郭骁才 《应用与环境生物学报》2001,7(3):297-301
细胞质雄性不育 (cytoplasmicmalesterility ,CMS) ,表现为小孢子发育异常、不能产生花粉或花粉败育 ,但卵细胞发育正常、可接受外来花粉而正常结实 ,系母性遗传 ,即细胞质遗传[1~ 4 ] .CMS的重要性 ,首先表现为在农业生产上的巨大经济应用价值[2~ 4 ] .杂种优势的发现和利用为粮食生产带来了革命 ,但杂种种子的生产过程却是很繁杂的 ,核心是要阻止母本的自花授粉结实、保证母本植株上所结的种子全部是杂种 ,即种子的纯度很高才能保证农业生产上的应用 .CMS ,由于其不能产生可育的花粉 ,即无自花授粉结… 相似文献