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11.
工业传统混酸硝化法严重腐蚀设备和污染环境,同时对硝基氯苯选择性较低,针对这个问题,研究了在HZSM-5分子筛催化下,五氧化二氮对氯苯的硝化反应。由于HZSM-5优异的择形性,对硝基氯苯在硝化产物中的比例从原先的42%提高到81%。实验考察了反应温度、反应时间、催化剂用量及Si/Al等因素对反应结果的影响。研究表明,在温度为50℃,时间为1h,5gSi/Al质量比为260的催化剂HZSM-5作用下,反应条件最佳,此时氯苯硝化反应得率达到50%,对位选择性为85%。  相似文献   
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何立志  阳智敏  周春义 《广东化工》2010,37(11):151-152
采用毛细管柱气相色谱定量法同时测定水中11种痕量氯苯类化合物的方法。石油醚萃取富集水中氯苯类化合物,用电子捕获检测器检测,整个分析过程只需25min,检出限可达0.001~0.01μg·L-1,均都低于GB/T5750.8-2006,每种化合物的回收率在80%~105%,相对标准标准偏差在1.5%~4.5%之间。  相似文献   
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介绍了氯化苯生产过程中水洗酸废水综合利用的情况,通过工艺改造,实现了废酸的零排放,且具有显著的经济和社会效益。  相似文献   
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氯苯在飞灰表面低温生成二恶英的特性   总被引:1,自引:0,他引:1  
以1,2,3-三氯苯作为前趋物,在管式炉中研究了其在垃圾焚烧飞灰表面低温生成二恶英的分布特性,运用高分辨气相色谱/低分辨质谱仪分别测定了气相和固相中的二恶英总量以及毒性当量I-TEQ值.实验结果表明, 250℃是1,2,3-三氯苯在飞灰表面生成二恶英的最佳温度,生成的二恶英主要分布在气相中,与五氯酚相比,氯苯属于反应活性低的二恶英前趋物.  相似文献   
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介绍了氯苯副产盐酸中微量苯和氯苯含量的测定方法、测定过程及测定结果。  相似文献   
16.
杨瑞良 《氯碱工业》2008,44(6):29-30
叙述了在氯苯生产中氯化反应温度过高产生的危害,详细分析了氯化反应温度过高的原因及处理措施.  相似文献   
17.
Persistent organic pollutants (POPs) encompass an array of anthropogenic organic and elemental substances and their degradation and metabolic byproducts that have been found in the tissues of exposed animals, especially POPs categorized as organohalogen contaminants (OHCs). OHCs have been of concern in the circumpolar arctic for decades. For example, as a consequence of bioaccumulation and in some cases biomagnification of legacy (e.g., chlorinated PCBs, DDTs and CHLs) and emerging (e.g., brominated flame retardants (BFRs) and in particular polybrominated diphenyl ethers (PBDEs) and perfluorinated compounds (PFCs) including perfluorooctane sulfonate (PFOS) and perfluorooctanic acid (PFOA) found in Arctic biota and humans. Of high concern are the potential biological effects of these contaminants in exposed Arctic wildlife and fish. As concluded in the last review in 2004 for the Arctic Monitoring and Assessment Program (AMAP) on the effects of POPs in Arctic wildlife, prior to 1997, biological effects data were minimal and insufficient at any level of biological organization. The present review summarizes recent studies on biological effects in relation to OHC exposure, and attempts to assess known tissue/body compartment concentration data in the context of possible threshold levels of effects to evaluate the risks. This review concentrates mainly on post-2002, new OHC effects data in Arctic wildlife and fish, and is largely based on recently available effects data for populations of several top trophic level species, including seabirds (e.g., glaucous gull (Larus hyperboreus)), polar bears (Ursus maritimus), polar (Arctic) fox (Vulpes lagopus), and Arctic charr (Salvelinus alpinus), as well as semi-captive studies on sled dogs (Canis familiaris). Regardless, there remains a dearth of data on true contaminant exposure, cause-effect relationships with respect to these contaminant exposures in Arctic wildlife and fish. Indications of exposure effects are largely based on correlations between biomarker endpoints (e.g., biochemical processes related to the immune and endocrine system, pathological changes in tissues and reproduction and development) and tissue residue levels of OHCs (e.g., PCBs, DDTs, CHLs, PBDEs and in a few cases perfluorinated carboxylic acids (PFCAs) and perfluorinated sulfonates (PFSAs)). Some exceptions include semi-field studies on comparative contaminant effects of control and exposed cohorts of captive Greenland sled dogs, and performance studies mimicking environmentally relevant PCB concentrations in Arctic charr. Recent tissue concentrations in several arctic marine mammal species and populations exceed a general threshold level of concern of 1 part-per-million (ppm), but a clear evidence of a POP/OHC-related stress in these populations remains to be confirmed. There remains minimal evidence that OHCs are having widespread effects on the health of Arctic organisms, with the possible exception of East Greenland and Svalbard polar bears and Svalbard glaucous gulls. However, the true (if any real) effects of POPs in Arctic wildlife have to be put into the context of other environmental, ecological and physiological stressors (both anthropogenic and natural) that render an overall complex picture. For instance, seasonal changes in food intake and corresponding cycles of fattening and emaciation seen in Arctic animals can modify contaminant tissue distribution and toxicokinetics (contaminant deposition, metabolism and depuration). Also, other factors, including impact of climate change (seasonal ice and temperature changes, and connection to food web changes, nutrition, etc. in exposed biota), disease, species invasion and the connection to disease resistance will impact toxicant exposure. Overall, further research and better understanding of POP/OHC impact on animal performance in Arctic biota are recommended. Regardless, it could be argued that Arctic wildlife and fish at the highest potential risk of POP/OHC exposure and mediated effects are East Greenland, Svalbard and (West and South) Hudson Bay polar bears, Alaskan and Northern Norway killer whales, several species of gulls and other seabirds from the Svalbard area, Northern Norway, East Greenland, the Kara Sea and/or the Canadian central high Arctic, East Greenland ringed seal and a few populations of Arctic charr and Greenland shark.  相似文献   
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对硝酸-硫酸-废酸-磷酸体系中的氯苯硝化反应进行了动力学实验研究,并得到了反应的宏观动力学方程.  相似文献   
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