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71.
4月12日凌晨,齐鲁石化公司烯烃厂芳烃装置在检修停车过程中,投用了刚刚竣工的密闭排放系统。在停车倒空、排放量巨大的情况下,装置区无明显异味、无油气、51号污油井不需要人工捞油,标志着密闭排放系统改造成功。  相似文献   
72.
Since the announcement by Fleischmann and Pons that the excess enthalpy generated in the negatively polarized Pd–D-D2O system was attributable to nuclear reactions occurring inside the Pd lattice, there have been reports of other manifestations of nuclear activities in this system. In particular, there have been reports of tritium and helium-4 production; emission of energetic particles, gamma or X-rays, and neutrons; as well as the transmutation of elements. In this communication, the results of Pd–D co-deposition experiments conducted with the cathode in close contact with CR-39, a solid-state nuclear etch detector, are reported. Among the solitary tracks due to individual energetic particles, triple tracks are observed. Microscopic examination of the bottom of the triple track pit shows that the three lobes of the track are splitting apart from a center point. The presence of three α-particle tracks outgoing from a single point is diagnostic of the 12C(n,n′)3α carbon breakup reaction and suggests that DT reactions that produce ≥9.6 MeV neutrons are occurring inside the Pd lattice. To our knowledge, this is the first report of the production of energetic (≥9.6 MeV) neutrons in the Pd–D system. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
73.
Historical documents and classic works together with recent specialized literature have described Harmful Algal Blooms (HABs) in the Gulf of California. This is a review of HABs impact (qualitative and quantitative) during the last decades in the Gulf of California on wild (mammals, birds, fishes, and invertebrates) and cultured animals (shrimps and fishes). Microalgal species responsible of noxious effects are Noctiluca scintillans, Cochlodinium polykrikoides, Gymnodinium catenatum, Prorocentrum minimum, Akashiwo sanguinea, Chattonella subsalsa Ch. marina, Chattonella sp., Heterocapsa sp., Dinophysis sp., Fibrocapsa japonica, Heterosigma akashiwo, Thalassiosira sp., Chaetoceros spp., Pseudo-nitzschia australis, P fraudulenta, Pseudo-nitzschia sp., Trichodesmium erythraeum and ScSchizotrix calcicola. Emphasis is given to the necessity to continue with interdisciplinary studies in oceanography, ecology, toxicology and toxinology interrelated with biomedical sciences such as physiology, pathology, epidemiology and animal health.  相似文献   
74.
在存在火灾或者高温作业场所,作业人员穿戴的防护服热防护性能指标好坏直接影响到使用者的人身财产安全。本文主要针对市面上常见的五种热防护服,对其热辐射防护指标进行分析研究,通过研究不同产品的热辐射性能,对相应的测试数据进行汇总对比,找出相应的关联性。本研究结果表明:每层面料的热防护时间与整体防护时间之间的关系并非简单叠加的线性关系;对于本质阻燃材料在热辐射暴露时间越长,其热分解速度加快,更容易产生热防护失效现象;目前,铝箔复合材料仍是市面高隔热防护性能的主流选择。另外,本文对不同热辐射热流密度下不同产品进行热辐射实验并汇总数据,希望能够为今后防护服的设计和改进提供技术参考,为相应的标准制定提供数据支撑,从而促进工业和消防救援行业热防护服产品发展。  相似文献   
75.
干旱指标及其在新疆阿勒泰地区干旱监测分析中的应用   总被引:2,自引:0,他引:2  
干旱是限制新疆阿勒泰地区农牧业生产可持续发展最主要的自然灾害之一,研究适合该区的干旱指标,是进行有效干旱监测的基础。采用新疆阿勒泰地区7个气象站1961-2008年4-10月月平均气温、降水量资料,首先通过Thomthwaite方法计算潜在蒸发量确定K干旱指数,然后对R指数、Z指数、K指数3种干旱指标进行了分析,结果表明,在监测诊断干旱轻重程度上,K指数能较客观地反映出干旱程度,R指数和Z指数监测干旱程度较轻。在此基础上,基于K指数建立的阿勒泰地区干旱监测评价的强度指数和面积指数,对该地区近48年来干旱的变化进行了分析,表明该地区干旱灾害主要集中在春夏季节,春夏连旱几率较高,强度较大;该地区干旱灾害具有阶段性特征,近年来干旱发生的频次有增多的趋势,其中秋季干旱相对较为明显。  相似文献   
76.
杨欢  杨森  申展  戴文俊 《装备环境工程》2023,20(10):139-146
目的 以不同浓度的双氧水溶液对活性炭纤维进行氧化改性,制备SO2、NOx腐蚀气氛吸附材料。方法采用红外光谱、X射线衍射仪、X射线光电子能谱仪等表征方式,揭示双氧水改性对活性炭纤维孔隙结构、表面物理化学性质、吸附性能的影响,并将装有吸附材料的防护包装贮存于湿热海洋气候环境中,验证腐蚀气氛控制效果。结果 双氧水改性活性炭纤维后,其表面官能团未发生变化,比表面积先减小、后增大。改性后,活性炭纤维表面活性位点有所增加,对应的吸附性能显著增加,30%双氧水改性活性炭纤维对SO2、NO2、NO的饱和吸附量分别为100、153、128 mg/g,与改性前相比,分别提高了67%、180%、137%。应用吸附材料的防护包装内部腐蚀气氛浓度在3个月内几乎为0。结论 双氧水改性活性炭纤维具有良好的腐蚀气氛吸附性能,在长贮微环境中具有良好应用前景。  相似文献   
77.
Sorption of 3,4-dichloroaniline (3,4-DCA) on four typical Greek agricultural soils, with distinct texture, organic matter content and cation exchange capacities, was compared by using sorption isotherms and the parameters calculated from the fitted Freundlich equations. The sorption process of 3,4-DCA to the soil was completed within 48-72 h. The 3,4-DCA sorption on all soils was well described by the Freundlich equation and all sorption isotherms were of the L-type. The sandy clay loam soil with the highest organic matter content and a slightly acidic pH was the most sorptive, whereas the two other soil types, a high organic matter and neutral pH clay and a low organic matter and acidic loam, had an intermediate sorption capacity. A typical calcareous soil with low organic matter had the lowest sorption capacity which was only slightly higher than that of river sand. The 3,4-DCA sorption correlated best to soil organic matter content and not to clay content or cation exchange capacity, indicating the primary role of organic matter. The distribution coefficient (K(d)) decreased with increasing initial 3,4-DCA concentration and the reduction was most pronounced with the highly sorptive sandy clay loam soil, suggesting that the available sorption sites of the soils are not unlimited. Liming of the two acidic soils (the sandy clay loam and the loam) raised their pH (from 6.2 and 5.3, respectively) to 7.8 and reduced their sorption capacity by about 50 %, indicating that soil pH may be the second in importance factor (after organic matter) determining 3,4-DCA sorption.  相似文献   
78.
The physical (pH, Dissolved Solids, Dissolved Oxygen, conductivity, water depth temperature) and bacteriological (Total coliforms, Faecal coliforms) characteristics of 22 hand-dug wells in oil-rich Niger Delta of Nigeria were investigated. All coliforms counts (Log10 MPN/100 ml) varied from well to well ranging from 0 to 6.0 although faecal coliform counts were markedly lower (0–3.5 vs 1.0–6.0). When both seasons were compared, faecal coliform counts were significantly higher (t test; P < 0.05) during the wet season whereas no significant difference was observed in respect of total coliforms. Unlike the total coliforms, faecal coliform counts increased in wells close to septic tanks during the wet season. Although a declining trend was observed during the wet season, the values of the physical parameters were within WHO limits. The pH was slightly acidic (Mean ± SD: dry season, 6.04 ± 0.66; wet, 6.43 ± 0.62) and may be attributed to emissions from gas flaring and petroleum refining activities, which is common in the area. While the total coliform counts reflected the unsanitary habits of the well users, the detection of faecal coliforms exceeding recommended numbers in 63% of the wells render them unfit for domestic use. The public health implication is obvious considering the increasing number of people using the wells due to the rapid urbanization of the oil-rich region.  相似文献   
79.
Recovery of nickel, cobalt and some salts from spent Ni-MH batteries   总被引:2,自引:0,他引:2  
This work provides a method to help recover nickel, cobalt metals and some of their salts having market value from spent nickel-metal hydride batteries (SNiB). The methodology used benefits the solubility of the battery electrode materials in sulfuric or hydrochloric acids. The results obtained showed that sulfuric acid was slightly less powerful in leaching SNiB compared to HCl acid. Despite that, sulfuric acid was extremely applied on economic basis. The highest level of solubility attained 93.5% using 3N sulfuric acid at 90 degrees C for 3h. The addition of hydrogen peroxide to the reacting acid solution improved the level of solubility and enhanced the process in a shorter time. The maximum recovery of nickel and cobalt metals was 99.9% and 99.4%, respectively. Results were explained in the light of a model assuming that solubility was a first order reaction. It involved a multi-step sequence, the first step of which was the rate determining step of the overall solubility. Nickel salts such as hydroxide, chloride, hexamminenickel chloride, hexamminenickel nitrate, oxalate and nickel oleate were prepared. With cobalt, basic carbonate, chloride, nitrate, citrate, oleate and acetate salts were prepared from cobalt hydroxide Cost estimates showed that the prices of the end products were nearly 30% lower compared to the prices of the same chemicals prepared from primary resources.  相似文献   
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