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741.
香港消防性能化设计的简略介绍   总被引:3,自引:1,他引:2  
赵龙德 《火灾科学》2001,10(4):241-244
介绍了香港在消防工种领域性能化设计的应用和发展。简单地阐述了国际上的消防工程性能化设计的发展。概述目前的性能化设计现状并给出经验总结。  相似文献   
742.
Fire management of grasslands is best executed based on an understanding of the fundamental properties of grassland components, structures, and environments, and the nature of fire behavior in grassland fuels. The art of controlled burning combines experience, practicality, empirical knowledge, and sensitivity, with the effects of fire, the role of fire (particularly under natural conditions), inherent climatic conditions, and sound ecological management objectives. Some of the properties, effects, roles, conditions, experiences, and objectives of grassland burning are presented.  相似文献   
743.
In several species of ants, queens often form temporary cooperative associations during colony foundation. These associations end soon after the eclosion of the first workers with the death or expulsion of all but one of the queens. This study examined competition between foundress queens of the fire ant Solenopsis invicta. Although attacks by the workers contributed to queen mortality, queens gained no advantage by producing more workers than their co-foundresses. Restriction fragment length polymorphism analysis of mitochondrial DNA showed that the queen producing more workers during colony founding was no more likely to survive than the less productive queen. In experimentally manipulated colonies in which all the workers were daughters of only one of the queens, the mother of the workers was no more likely to survive than the unrelated queen. Queens producing diploid males reared fewer offspring but were as likely to survive as queens producing only workers. These results suggest that workers do not discriminate between related and unrelated queens within colonies. Aggressive encounters between queens were common. Queens were more likely to die or be expelled if paired with heavier queens or if they lost more weight than their co-foundress during the claustral period. Finally, when queens were separated by screens through which workers could pass, the workers usually attacked and killed the queen farther from the brood. These results suggest that queen survival is promoted by a high fighting ability relative to co-foundresses, rather than by increased worker production, and that workers respond to queen differences that are independent of kinship. Received: 8 September 1995/Accepted after revision: 5 March 1996  相似文献   
744.
The formulation and implementation of new fire policies in the national forests depend upon public acceptance. A national survey of organized groups of forest users indicates that, contrary to the concern of many forest managers, considerable support exists for flexible fire suppression policies. Forest users are also willing to accept the risk associated with the manager's use of prescribed fire. However, important intergroup differences do exist. Such variation is discussed in relation to a number of socioeconomic variables, general fire knowledge, specific knowledge about the effects of low-intensity fires, and risk preference levels.  相似文献   
745.
This paper describes the development and implementation ofPREPLAN, A Pristine Environment Planning Language and Simulator, for two conservation areas in Australia, Kosciusko National Park (New South Wales) and Tutanning Nature Reserve (Western Australia).PREPLAN was derived from the North American gradient modeling systems and theForest Planning Language and Simulator (FORPLAN), but includes unique characteristics not previously available.PREPLAN includes an integrated resource management data base, modules for predicting site-specific vegetation, fuels, animals, fire behavior, and fire effects, and an English language instruction set.PREPLAN was developed specifically to provide available information and understanding of ecosystems to managers in a readily accessible and usable form, and to provide the motivation to conduct additional required research projects. An evaluation of the system's advantages and limitations is presented, and the way the utilization of such systems is improving natural area decision making throughout Australia is discussed.  相似文献   
746.
Sustainable management of Electronic waste (E-waste) is a major challenge for contemporary India, an emerging economy burdened with both the domestic generation and illegal import of E-waste. Considering the ever-increasing complexities of E-waste in Indian cities, this paper aims to evaluate the current trends, opportunities and challenges associated with consumption of electronic items (with respect to computers and mobile phones) and disposal of E-waste in urban India. Bangalore, a city popularly known as the ‘Silicon Valley of India’, is considered as a case study in order to evaluate public awareness, household consumption and E-waste disposal behaviours. The city profile of Bangalore indicates that it has a rapidly emerging market for electronics and thus, has the potential to act as a ‘model’ for evaluating the issues concerning E-waste in metropolitan India. Questionnaires were distributed originally among 300 households with an effective response rate of 63.3%. The results indicate that the majority of households (59.3%) still retain their obsolete electronics due to lack of knowledge about proper E-waste management. High awareness about E-waste and high willingness to recycle/repair their E-waste (above 80% in both cases) are yet to be translated into responsible disposal/recycling behaviour as 95.8% of households have no knowledge about the presence of any formal recycling centre. Income, education, age and gender dimensions associated with E-waste disposal behaviour and awareness were also evaluated. Although we found no gender differences for most of the parameters, there have been some interesting correlations in age and income-wise segregation of disposal behaviour. We noted that the city of Bangalore still possesses some typical Indian socio-cultural characteristics, such as considering E-waste as ‘valuables’, changing several hands before final disposal, defying ‘brand’ or ‘looks’ consciousness, etc., which could be directed towards responsible E-waste disposal behaviours. We suggest that establishing appropriate and convenient E-waste collection/recycling facilities, ensuring responsible household disposal behaviour, implementing effective laws and legislation, and organizing mass E-waste awareness campaigns would aid in addressing the current E-waste concerns in the city.  相似文献   
747.
火灾时人员安全疏散可靠性评估   总被引:7,自引:3,他引:7  
本文给出了一个计算人员安全疏散概率的算法,用以评价火灾时室内人员的危险程度。算法假定影响安全疏散的变量为随机变量,以逃生概率做为疏散评价指标,文中附有算例。  相似文献   
748.
Practitioners and academic researchers increasingly look to evaluation of health impact assessment (HIA) to improve its practice, its efficiency and its legitimacy. Evaluation is also used to account to policy-makers, who express doubts that the benefits of HIA justify its costs. Until recently evaluation of HIA focused on instrument design and procedures but now the focus needs to shift to analysis of the interaction of HIA and decision-making. Multiple case studies have been applied to identify the conditions in which HIA produces the desired benefits. These studies used analytical concepts derived from the literature on evaluation, knowledge utilization, science of sociology and knowledge management.This paper describes a case study in which the strategic motives of the decision-makers affected the impact of an HIA. This HIA comprised of a quantitative environmental model ‘City & Environment’ that was used to assess environmental health impacts of an urban reconstruction plan in a Dutch city. The evaluation of the HIA shows that the decision to follow the recommendations of the HIA was part of a damage control strategy. The more HIA goals deviate from the policy problem and the less HIA is embedded in institutional procedures, then the more HIA impact will be subject to strategic decision-making behaviour. Appropriate cognitive and social strategies are needed to avoid ‘negative learning’ in those the HIA seeks to influence.  相似文献   
749.
基于双龙风景区自驾车游客的实地问卷调查资料,得出双龙风景区自驾车游客的客源地构成;分析了自驾车游客的年龄、职业、收入等结构特征及其出游时间、旅游偏好、消费水平等行为特征;揭示了制约自驾车游客出游的主要因素;针对自驾车游客的旅游体验与评价,提出了促进自驾车旅游发展的建议,以期为相关旅游企业及旅游管理部门的决策提供参考依据。  相似文献   
750.
地震次生火灾对人类的危害极大.本文在对以往历史数据的统计基础上,模拟出城市每10万平方米建筑地震次生火灾发生件数与地震地面加速度峰值的关系,并由此计算了地震后火灾发生的件数.  相似文献   
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