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991.
化工厂危险化学品安全管理浅谈 总被引:1,自引:0,他引:1
化工厂危险化学品种类繁多、性质各异.危险化学品在存放、管理、使用过程中稍有不慎,就会发生安全事故.化工厂员工务必要加强安全防范意识,对危险化学品进行科学合理的管理、使用,并且对化工厂常见事故有一定的处理能力,确保将化工厂的危险系数降到最低. 相似文献
992.
采用复合脱酸剂,对北疆高酸原油进行了脱酸研究。对脱酸剂组成进行详细的优选,考察了反应温度、反应时间、脱酸剂加量对脱酸率的影响,考察了超声辐照对脱酸的强化作用。实验结果表明:采用环己胺为中和剂、乙二醇为萃取溶剂组成的脱酸剂对高酸原油具有较高的脱酸率,且没有乳化现象。超声辐照对脱酸过程具有强化作用,使反应时间显著缩短;含环己胺质量分数为30%的乙二醇具有良好的脱酸性能,加量为15%wt时,脱酸率达到86.5%,采用减压蒸馏回收环烷酸,乙二醇回收率为99.3%,环己胺回收率为96.6%,回收的环烷酸纯度较高,酸值达到167 mg KOH/g。 相似文献
993.
Zhihong Wang Zhe Lü Bo Wei Kongfa Chen Xiqiang Huang Weiping Pan Wenhui Su 《Electrochimica acta》2011,(19):6688
A single-chamber solid oxide fuel cell made of Ni/YSZ anodes, YSZ electrolytes and SDC-impregnated LSM cathodes was tested in methane–oxygen mixture at furnace temperature equal to 700 °C. Two Ag wires were arranged on the anode surface to in situ measure the changes of the local anode resistance (Rs) during testing. Oscillations of the Rs, the cell voltage and the actual temperature of the cell were observed and attributed to Ni/NiO redox cycles. Steady-state tests of the cell showed the corresponding oscillation patterns mainly depended on methane-to-oxygen ratio (M = 1, 2). Higher current density (J) to a certain extent could suppress NiO reduction and promote Ni oxidation. Scanning electron micrographs confirmed that Ni/NiO redox cycles had occurred mainly near the anode surface. The obtained results imply that gradual reoxidation of the Ni-anodes accompanying the various oscillation behaviors plays an important role in the degradation of the SC-SOFCs, especially under oxidation conditions. 相似文献
994.
Nanocrystalline thin-film electrolytes of Sm3+ and Nd3+ co-doped ceria have been deposited on polycrystalline alumina substrates via RF magnetron sputtering. It is found that with the increase of substrate temperature from room temperature to 600 °C, the structure of the film varies from (1 1 1) preferred orientation to random orientation, accompanied by an enhancement in electrical conductivity. It is estimated that the activation energy for oxygen ion migration along (1 1 1) orientation may be higher than other crystal orientations, resulting in a lower conductivity of the (1 1 1) barrier textured co-doped ceria film electrolyte. It also indicates that the electrical conduction is predominantly due to the oxygen ions. 相似文献
995.
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997.
测量不确定度是与测量结果相联系的参数,表征合理地赋予被测量之值的分散性.是表征测量结果的质量高低的重要参数,也国家实验室能力认可委员会对实验室能力的一种要求.通过对项目不确定度的评定,分析其不确定度的来源和影响因子,可以指导我们在测量中如何降低和控制不确定度,提高测量的准确性.文章就实际工作中噪声的不确定度的进行了析与... 相似文献
998.
Rice straw fiber‐high density polyethylene (HDPE) composites were prepared to investigate the effects of rice straw fiber morphology (rice straw refined fiber, rice straw pellet, rice straw strand), fiber content (20 and 40 wt %), and maleic anhydride polyethylene (MAPE) concentration (5 wt %) on the mechanical and thermal properties of the rice straw fiber‐HDPE composites in this study. Rice straw refined fiber exhibited more variability in length and width, and have a higher aspect ratio of 16.3. Compared to the composites filled of rice straw pellet, the composites made of the refined fiber and strand had a slightly higher tensile strength and lower tensile elongation at break. The tensile and flexural strength of the composites increased slightly with increasing rice straw fiber content up to 40 wt %, while the tensile elongation at break decreased. With addition MAPE, the composites filled with 20 wt % rice straw fiber showed an increase in tensile, flexural and impact strength and a decrease in tensile elongation at break. Differential scanning calorimetry showed that the fiber addition and morphology had no appreciable effect on the crystallization temperature of the composites but decreased the crystallinity. The scanning electron microscopy observation on the fracture surface of the composites indicated that introduction of MAPE to the system resulted in promotion in fiber dispersion, and an increase in interfacial bonding strength. Fiber breakage occurred significantly in the composites filled with refined fiber and strand after extruding and injection processing. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
999.
Zhenhua Zhang Bo Peng Ping Ding Bo Liu Yuehui He Kechao Zhou Yongfang Li Chunyue Pan Yingping Zou 《应用聚合物科学杂志》2011,120(5):2534-2542
Two new alternating copolymers based on dithienyl benzotriazole segment and phenylene vinyl unit were synthesized by Heck cross coupling method. The polymers exhibited broad absorption bands (from 300 nm to 752 nm for P1 , and from 300 nm to 654 nm for P2 ) in the UV‐visible region with optical bandgap ranging between 1.6 and 1.9 eV and proper electronic energy levels measured by cyclic voltammetry. The photovoltaic properties of the polymers as electron donors with 6.6‐phenyl C61‐butyric acid methyl ester as the electron acceptor in a bulk heterojunction structures were reported. Preliminary results showed moderate power conversion efficiency of 0.36% and 0.4%, respectively, under the illumination of AM 1.5, 100 mW/cm2 with a device structure of ITO/PEDOT : PSS/polymer : PC60BM (1 : 3)/Ca/Al. Furthermore, the side chain effect on properties has also been investigated. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
1000.
Weijie Zhao Jing Zhang Jiaqi Pan Wenhui Zhao Jiantao Niu Jianfeng Qiu Chaorong Li 《Ceramics International》2018,44(15):18337-18343
The 1D Ag3PO4 sensitized SrTiO3 nanowires are prepared by simple route of electrospinning-in situ deposition technique. The results of the thermogravimetry (TG), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive Spectrometer (EDS), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and UV–Visible diffuse reflectance spectroscopy (UV–Vis) indicate that the Ag3PO4 nanoparticles has been deposited on the surface of the SrTiO3 nanowires successfully. Experimental results showed that compared with pure SrTiO3, the as-prepared 1D Ag3PO4 sensitized SrTiO3 nanowires exhibit obvious enhancement of photocatalytic performance and stability. Especially, the Ag3PO4/SrTiO3 (3AS sample) had a satisfactory photocatalytic activity for degrading methylene blue (MB) more than 98% under visible light irradiation. As to pure SrTiO3 and Ag3PO4, only 9.8% and 49% of MB was decomposed after 35?min irradiation respectively. Furthermore, the mechanism of the enhancing photocatalytic activity could be ascribed to the nano-heterojunction of the Ag3PO4/SrTiO3, the visible light response of the Ag3PO4, and the 1D structure of the nanowires. 相似文献