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91.
采用真空吸滤和挤压过滤两段组合式提取装置两次提取麦草浆黑液,能获得高且稳定的黑液提取率。探讨了黑液提取率与浆料洗涤时间、水量的关系及洗后浆所达到的洗净程度等。 相似文献
92.
93.
萃取法去除硝基苯生产废水中的硝基酚 总被引:12,自引:0,他引:12
用苯、N 50 3 苯作萃取剂对硝基苯生产废水进行处理 ,用苯萃取 3次可使硝基酚的含量达国家规定的三级排放标准 ,而用N 50 3 苯萃取剂萃取废水 2次可使硝基酚含量达到国家规定的一级排放标准。N 50 3的用量宜为萃取剂总量的 2 0 %~ 30 %。 相似文献
94.
从废葡萄核中提取油脂的研究 总被引:2,自引:0,他引:2
李晋芳 《辽宁城乡环境科技》2004,24(2):28-29,33
研究了从废葡萄核提取油脂的方法。确定以苯为萃取剂,苯与葡萄核的配比为3:1(VW),室温下苯萃取60min,出油率达17%以上。用碱性双氧水精制,活性炭脱色,可得到精制油品。讨论了不同操作条件对提取油脂产率和脱色效果的影响,从而确定了较佳的提取条件。 相似文献
95.
对GB/T17657和GB/18580规定的3种方法(萃取法、干燥器法、环境舱法)的影响因素进行了比较,认为应优先采用分光光度法检测甲醛释放量。在检测中要注意环境温湿度、显色及放置时间的掌握、样品平衡放置时间、仪器精度控制等因素。 相似文献
96.
97.
Łukasz Baka Róża Bazińska 《International journal of occupational safety and ergonomics》2016,22(1):32-39
Aim. The objective of the present study was to test the psychometric properties, reliability and validity of three job stressor measures, namely, the Interpersonal Conflict at Work Scale, the Organizational Constraints Scale and the Quantitative Workload Inventory. Method. The study was conducted on two samples (N?=?382 and 3368) representing a wide range of occupations. The estimation of internal consistency with Cronbach's α and the test–retest method as well as both exploratory and confirmatory factor analyses were the main statistical methods. Results. The internal consistency of the scales proved satisfactory, ranging from 0.80 to 0.90 for Cronbach's α test and from 0.72 to 0.86 for the test–retest method. The one-dimensional structure of the three measurements was confirmed. The three scales have acceptable fit to the data. The one-factor structures and other psychometric properties of the Polish version of the scales seem to be similar to those found in the US version of the scales. It was also proved that the three job stressors are positively related to all the job strain measures. Conclusions. The Polish versions of the three analysed scales can be used to measure the job stressors in Polish conditions. 相似文献
98.
Tânia Rodrigues Pereira Ramos Maria Isabel Gomes Ana Paula Barbosa-Póvoa 《Waste management (New York, N.Y.)》2013,33(8):1691-1703
This research has been motivated by a real-life problem of a waste cooking oil collection system characterized by the existence of multiple depots with an outsourced vehicle fleet, where the collection routes have to be plan. The routing problem addressed allows open routes between depots, i.e., all routes start at one depot but can end at the same or at a different one, depending on what minimizes the objective function considered. Such problem is referred as a Multi-Depot Vehicle Routing Problem with Mixed Closed and Open Inter-Depot Routes and is, in this paper, modeled through a mixed integer linear programming (MILP) formulation where capacity and duration constraints are taken into account. The model developed is applied to the real case study providing, as final results, the vehicle routes planning where a decrease of 13% on mileage and 11% on fleet hiring cost are achieved, when comparing with the current company solution. 相似文献
99.
In this paper, the exploitation of petroleum resources in India is analyzed by developing a dynamic optimization modeling framework—PETEX. This model combines the practical aspects in determining optimal rates of extraction of oil and gas from a reservoir with a hybrid approach to estimating the discovery rate of petroleum resources in the future, additionally incorporating a stochastic specification to capture the uncertainty associated with discovery. The model acts as an aid to joint production–investment decision making for the entire supply process from drilling through production and in determining the import requirement to meet the country’s oil demand. The model results and sensitivity analysis suggest an acute requirement of sustained infusion of investment into the various upstream activities at a rate much higher than the current levels in order to bridge the demand—supply gap for crude oil. With the opening up of the Indian economy, it is hoped that the participation of the private sector in upstream activities would increase thereby increasing the investments available for upstream activity. 相似文献
100.
萃取—汽提法处理硝基苯废水的研究 总被引:11,自引:1,他引:11
先用苯萃取使废水中硝莽本的浓度达3ppm以下,再用水蒸气汽提使废水中的苯浓度达10ppm以下,并使硝基苯浓度进一步降低,处理后的废水全面达到国家二级排放标准。苯和萃取出的硝基苯都可回收利用.。 相似文献