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341.
342.
Endosulfan in China 1—gridded usage inventories 总被引:9,自引:0,他引:9
Jia H Li YF Wang D Cai D Yang M Ma J Hu J 《Environmental science and pollution research international》2009,16(3):295-301
Background, aim, and scope Endosulfan, an organochlorine pesticide (OCP), is genotoxic in mammalian cells and generally considered to be toxic and classified
by the World Health Organization and the US Environmental Protection Agency as priority pollutants and a nominator for inclusion
in a future iteration of the persistent organic pollutants treaty. Endosulfan is a currently used pesticide and still being
used worldwide. The general trend of total global endosulfan use has increased continuously since the first year when this
pesticide was applied. It is critical to create national endosulfan usage/emission inventories for China to carry out source–receptor
relation analysis, risk assessment, and other research related to endosulfan in this country. Chinese inventories have been
published for some OCPs, such as technical HCH and lindane, DDT, and chlordane; for endosulfan, however, there has not been
any usage inventory available on any scales (national or provincial), although endosulfan has been widely used since 1994
in this country. This is the first part of the work. The goal of this paper is to quantify the historical production and usage
of endosulfan in China and to compile gridded historical usage inventories of endosulfan for this country. Based on these
usage inventories, emission and residue inventories will be created, which is the goal of the second part of the work.
Materials and methods Due to the lack of national production and usage information of endosulfan in China, a method to estimate the use of endosulfan
was developed. First, information of crops on which endosulfan is applied and average endosulfan use and annual application
frequencies of endosulfan on these crops were collected. Secondly, usage of endosulfan on each crop was estimated using the
national cropland area for each province from Chinese government reports. Finally, with the help of GIS (geographic information
system), the usage data of this insecticide was allocated to a grid system, with a 1/4° longitude by 1/6° latitude resolution,
with a size for each grid cell of approximately 25 km by 25 km.
Results and discussion The use of endosulfan in agriculture in China started on cotton in 1994, and on wheat, tea, tobacco, apples, and other fruits
in 1998. Endosulfan usage on cotton, wheat, tea, tobacco, and apples in China has been estimated to be approximately 25,700 t
between 1994 and 2004. The province with the highest usage of endosulfan is Henan Province, with a total usage reaching 4,000 t,
followed by the uses in Xinjiang Autonomous Region (3,200 t), Shandong Province (3,000 t), Hebei Province (2,100 t), and Anhui
Province (1,900 t). Gridded usage inventories of endosulfan at a 1/4° longitude by 1/6° latitude resolution have been created,
which indicate that the intensive endosulfan use was in the south of Hebei Province, west of Shandong Province, east of Henan
Province, north of Anhui Province, east of Jiangsu Province, and some areas in Yunnan Province and Xinjiang Autonomous Region.
General agreement has been found between the usage data from our estimation and the small amount of usage data published in
China.
Conclusions This is the first national gridded endosulfan usage inventory produced for China. The annual applications of endosulfan from
1994 to 2004 in China were estimated based on the total areas of major crops, on which endosulfan was applied, and spatial
distribution of the application was generated at provincial and prefecture levels. With the help of GIS, endosulfan usage
based on prefecture was transferred to a 1/4° longitude by 1/6° latitude gridding system. The satisfaction of the inventories
was supported by the consistence between the estimation of the annual usage and the reported annual production of endosulfan.
Recommendations and perspectives This gridded endosulfan usage inventory created in this study will be improved upon availability of new information of endosulfan.
The usage inventories can be used to create gridded emission and residue inventories for this insecticide. It is believed
that this work will pave the way for further endosulfan studies in China and beyond. 相似文献
343.
344.
关中地区飑线天气的预测及灾害对策探讨 总被引:1,自引:0,他引:1
对1961~1990年发生在陕西省关中地区的飑线天气及其灾害进行了统计分析,并从天气形势背景方面对飑线的发生发展进行了研究和分析,同时就飑线的预测和防灾对策进行了探讨。 相似文献
345.
采用过硫酸钾(K2S2O8)-偶氮二异丁咪唑啉盐酸盐(VA-044引发剂)复合引发体系合成了聚硫氯化铝-聚丙烯酰胺(PACS-PAM)杂化高分子絮凝剂。以特性黏度为指标,考察了引发剂配比、引发剂总用量、单体质量浓度、总铝浓度(AlT)、反应温度和反应时间等因素对杂化絮凝剂PASC-PAM的合成影响,结果表明,杂化絮凝剂PACS-PAM的最佳合成条件为引发剂K2S2O8与偶氮VA-044质量比为3:1、引发剂总用量为单体总质量的0.2%、单体质量浓度为0.21 g/mL、总铝浓度(AlT)为0.15 mol/L、反应温度为50 ℃、反应时间为3 h,在最佳条件下合成的杂化高分子的特性黏度为14.70 dL/g。电导率分析、红外光谱(FTIR)分析和热重-差热(DTA-TGA)分析表明,杂化絮凝剂中有机组分同无机组分是通过PAM分子链端的硫酸根离子(—SO42-)的桥连作用以离子键形式连接的。对黄泥悬浊液的絮凝效果研究表明,杂化絮凝剂PASC-PAM的絮凝效果优于复配絮凝剂PASC-PAM。 相似文献
346.
采用UASB-SBR-絮凝工艺处理地沟油制生物柴油废水,考察了各个阶段的废水处理效果。实验结果表明:UASB稳定运行阶段进水COD约为15000mg/L时,COD去除率约为87%,出水COD在2500mg/L以下,出水挥发性脂肪酸(VFA)浓度为4~6mmol/L,最佳容积负荷为15.0kg/(m3·d);采用SBR处理UASB出水,当容积负荷为1.5kg/(m3·d)时,出水COD在200mg/L以下,COD去除率在83%以上,ρ(NH3-N)在5mg/L以下,TP约为25mg/L。向SBR出水中加入质量分数为5%的聚合氯化铝进行化学除磷,加入量为5mL/L,处理后废水TP为4~6mg/L。处理后废水的COD,ρ(NH3-N),TP均达到CJ343-2010《污水排入城市下水道水质标准》的A类要求。 相似文献
347.
在三座DN150 mmX1600 mm有机玻璃塔试验装置上,考察了DN15的塑料拉西环、陶瓷拉西环和不锈钢拉西环三种材质填料对催化剂的粘附能力。在催化剂浓度5‰,液相负荷40 L/h,气相负荷80 m3/h的条件下,经过408h的连续运转,结果表明不同材质填料对催化剂的粘附能力均存在饱和状态,粘附在填料上的催化剂不随时间的持续增加而增多。其中,塑料填料对催化剂的粘附能力最强,增重0.125kg;不锈钢填料次之,增重为0.115kg;陶瓷填料最弱,增重为0.055kg。可为相关领域的工业应用提供借鉴和数据支撑。 相似文献
348.
Yao Z Wang Q He K Huo H Ma Y Zhang Q 《Journal of the Air & Waste Management Association (1995)》2007,57(11):1379-1386
On-board emission measurements were performed on 49 light-duty gasoline vehicles in seven cities of China. Vehicle-specific power mode distribution and emission characteristics were analyzed based on the data collected. The results of our study show that there were significant differences in different types of roads. The emission factors and fuel consumption rates on arterial roads and residential roads were approximately 1.4-2 times those on freeways. The carbon monoxide, hydrocarbon, and nitrogen oxides emission factors of Euro II vehicles were on average 86.2, 88.2, and 64.5% lower than those of carburetor vehicles, respectively. The new vehicle emission standards implemented in China had played an important role in reducing individual vehicle emissions. More comprehensive measures need to be considered to reduce the total amount of emissions from vehicles. 相似文献
349.
沉积物中2,2',4,4'-四溴联苯醚(BDE-47)在铜锈环棱螺体内的毒代动力学及其繁殖毒性 总被引:2,自引:0,他引:2
多溴联苯醚(PBDEs)是一种全球性的新型持久性有毒污染物,沉积物中高浓度的PBDEs是水生态系统的巨大风险源,2,2’,4,4’-四溴联苯醚(BDE-47)在PBDEs同系物中,目前分布最广,生物毒性最强。为评价沉积物中BDE-47向底栖动物体内转移的潜力及其对底栖动物的潜在繁殖毒性,将实验室培养的铜锈环棱螺(Bellamya aeruginosa)暴露于BDE-47加标沉积物中,研究了BDE-47在铜锈环棱螺体内的毒代动力学特性及其对铜锈环棱螺潜在繁殖力的影响。结果表明,铜锈环棱螺对沉积物中BDE-47吸收较快,代谢速度相对较慢,BDE-47在铜锈环棱螺体内具有较强的生物积累性。生物积累达理论平衡时,铜锈环棱螺体内BDE-47浓度为1440.67ng·g-1(以样品干质量计)。BDE-47在铜锈环棱螺体内的生物积累和生物净化过程较好地符合一级动力学模型,摄入速率常数、清除速率常数和生物-沉积物累积因子分别为0.10、0.038和2.75,生物半衰期为18d。铜锈环棱螺体内BDE-47达到90%稳定状态所需的理论时间约为60d。低浓度BDE-47(160ng·g-1)暴露对铜锈环棱螺的潜在繁殖力没有影响,但当浓度≥640ng·g-1时,铜锈环棱螺的繁殖力下降50%,这表明BDE-47对铜锈环棱螺具有繁殖毒性。铜锈环棱螺可作为指示沉积物中底栖生物长期暴露于BDE-47的良好检测模型。 相似文献
350.
Zihao Li Yang Geng Lei Ma Xiaoyin Chen Junhua Li Huazhen Chang Johannes W. Schwank 《Frontiers of Environmental Science & Engineering》2020,14(4):65