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241.
对硫化氢在油气田中的存在状况和危害性的研究结果表明,其主要危害是引起人员中毒以及氢脆作用造成的油田设备腐蚀。详细介绍了防治硫化氢的方法和措施,包括沉淀法、物理吸收法、钾碱法和氨水法、氧化法、金属氧化物吸收法、高压静电法等。对各种方法的防治机理及其应用状况进行了论述。  相似文献   
242.
通过对某铅冶炼厂职业铅危害情况及防治现状进行调查分析,提出了防治铅中毒、铅吸收的措施。  相似文献   
243.
论述了企业安全文化的作用,以及企业安全文化与安全教育的关系,提出安全教育是安全文化建设最根本、最有效途径。  相似文献   
244.
四川省环境中的汞   总被引:5,自引:0,他引:5  
熊定国  廖激 《四川环境》1994,13(1):46-49
本文较系统地报道了四川省地面水环境(河,湖原水,过滤水,沉积物),土壤,大气降水及生物-鱼体中的含量及分布特点,得出四川省环境中的汞与国内外相比属于罗低水平,地面水环境中汞的含量及溶解态汞由川东南向川西北递减,土壤中汞的含量与土壤类型,成土母质,降水条件等相关,鱼类对河水中汞有较强的富集能力,大气降水是四川省环境中汞的来源之一。文章还研究了汞的水环境容量,指出汞是四川省水环境较为脆弱的重要因素之一  相似文献   
245.
介绍了喷射钻井井底流场特性、喷嘴射流破岩机理、脉冲射流喷嘴、新型水力流道钻头的研究与应用情况,以及水射流技术在石油钻井用钻头上的应用前景。  相似文献   
246.
Thein vivo effects of deltamethrin (DM) on the blood sugar level, the acetylcholinesterase (AChE, EC 3.1.1.7) activities of the blood serum and various organs (heart, liver and intestine), the lactate dehydrogenase (LDH, EC 1.1.2.3), glutamic-oxaloacetic transaminase (GOT, EC 2.6.1.1), and glutamic-pyruvic transaminase (GPT, EC 2.6.1.2) activities of the blood serum, the adenosine triphosphatases (EC 3.6.1.3; Na+/K+-ATPase and Mg2+-ATPase) activities of the erythrocyte plasma membrane and the catalase (EC 1.11.1.6) activity of the liver were examined throughout 96 h in adult carp (Cyprinus carpio L.) Two sublethal concentrations, 1.0 and 1.5 µg/l of deltamethrin, were used. All fish survived the experiment except one, in an aquarium containing 1.5 ppb of DM, which died after 72 h.The AChE specific activity was significantly inhibited in the heart and intestine after 96 h at both concentrations compared to that in the control animals (P<0.05, Student'st-test), while there was no detectable difference between the two treatment. At the same time there was no detectable change in the liver. In the serum, the AChE activity almost remained unchanged; the only significant decrease could be measured after 96 h at 1.5 µg/l deltamethrin concentration. The blood glucose content exhibited interesting changes: after 24 h fish exposed at 1 µg/l DM seemed to be stressed, although this increase was not significant. When these fish became used to the new conditions (in practice this meant the presence of DM), the glucose level decreased, especially after 72 h. At the same time the control animals kept in similar circumstances showed a small insignificant decrease. Meanwhile fish in aquaria containing 1.5 µg/l DM reacted to the treatment with an increased blood glucose level after 48 h, and this did not change until the end of the treatment. The Na+/K+-ATPase activity decreased in a dose-dependant manner, while Mg2+-ATPase was less affected. A small increase in LDH level was observed, indicating damage of different muscle tissues. However, this phenomenon appeared only with the small dosage after 24 h (P<0.05). It has to be mentioned that the individual values varied to a large extent among of the eight fish.The GOT activities of the serum increased during the treatment. However, significant changes were only expressed after 72 and 96 h at 1 µg/l DM concentrations (P<0.01 andP<0.05), and after a similar long treatment at the high dosage (P<0.05, 72 and 96 h). The GPT did not change significantly in aquaria containing 1 µg/l DM. The only larger increase was measured after 96 h at 1.5 µg/l DM concentration (P<0.05). The catalase activity in the liver of treated carp remained practically at the same level compared to that in control fish.All these changes (concerning the primary effects of this compound) demonstrate the effect of DM on different fish enzymes, at low concentrations under laboratory conditions, which might be useful in practice for biomonitoring using fish.  相似文献   
247.
PrescreeningteratogenicpotentialofchlorinateddrinkingwaterdisinfectionbyproductsbyusingHydraregenerationasayJiYuantangDepar...  相似文献   
248.
电镀污泥焚烧渣资源化及无害化处理研究   总被引:5,自引:0,他引:5  
研究了用化学浸出方法从焚烧法预处理后的电镀污泥中回收有价金属-铜和镍及制取高质量的海绵铜和硫酸镍产品的工艺流程和技术条件,结果表明,选用H2SO4加入量为7mL加入量为7mL、液固比为3,浸出时间为1h,浸出温度为20℃,给料细度为-74μm占77%时,铜、镍的浸出效果较好,扩大试验也验证了其准确性,同时,探讨了浸出渣和除铁渣无害化处置的可能性。  相似文献   
249.
IntroductionImmobilizationorseparationofcontaminantscontainedinpollutedwaterisanobjectiveofincreasingimportanceinavarietyofenvironmentalsettings.Theextentofpesticidecontaminationofthewaterenvironmenthasrecentlyraisedmuchconcernbecauseofthepotentialhealthh…  相似文献   
250.
Atmospheric boundary layer (ABL) has a significant impact on the spatial and temporal distribution of air pollutants. In order to gain a better understanding of how ABL affects the variation of air pollutants, atmospheric boundary layer observations were performed at Sanshui in the Pearl River Delta (PRD) region over southern China during the winter of 2013. Two types of typical ABL status that could lead to air pollution were analyzed comparatively: weak vertical diffusion ability type (WVDAT) and weak horizontal transportation ability type (WHTAT). Results show that (1) WVDAT was featured by moderate wind speed, consistent wind direction, and thick inversion layer at 600~1000 m above ground level (AGL), and air pollutants were restricted in the low altitudes due to the stable atmospheric structure; (2) WHTAT was characterized by calm wind, varied wind direction, and shallow intense ground inversion layer, and air pollutants accumulated in locally because of strong recirculation in the low ABL; (3) recirculation factor (RF) and stable energy (SE) were proved to be good indicators for horizontal transportation ability and vertical diffusion ability of the atmosphere, respectively. Combined utilization of RF and SE can be very helpful in the evaluation of air pollution potential of the ABL.

Implications: Air quality data from ground and meteorological data collected from radio sounding in Sanshui in the Pearl River Delta showed that local air quality was poor when wind reversal was pronounced or temperature stratification state was stable. The combination of horizontal and vertical transportation ability of the local atmosphere should be taken into consideration when evaluating local environmental bearing capacity for air pollution.  相似文献   

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