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41.
通过在义安煤矿瓦斯综合治理技术的实践和研究,逐渐摸索出适合义安煤矿的瓦斯治理措施,从而达到了在地质条件复杂、瓦斯涌出量大、煤质极为松软煤层安全掘进回采的目的,为矿井安全生产打下坚实基础. 相似文献
42.
白象山铁矿-390m水平东大巷通过F4断层破碎带施工中,采用工作面探水注浆工艺封堵涌水,风镐配合钻爆法掘进,拱部管棚、前探梁保护,29U型钢棚+金属网作临时支护,钢纤维钢筋混凝土作永久支护,安全顺利地完成了施工任务。 相似文献
43.
Lu Kong Meng Tang Ting Zhang Dayong Wang Ke Hu Weiqi Lu Chao Wei Geyu Liang Yuepu Pu 《International journal of molecular sciences》2014,15(11):21253-21269
Nickel is associated with reproductive toxicity. However, the reproductive toxicity of nickel nanoparticles (Ni NPs) is unclear. Our goal was to determine the association between nickel nanoparticle exposure and reproductive toxicity. According to the one-generation reproductive toxicity standard, rats were exposed to nickel nanoparticles by gavage and we selected indicators including sex hormone levels, sperm motility, histopathology, and reproductive outcome etc. Experimental results showed nickel nanoparticles increased follicle stimulating hormone (FSH) and luteinizing hormone (LH), and lowered etradiol (E2) serum levels at a dose of 15 and 45 mg/kg in female rats. Ovarian lymphocytosis, vascular dilatation and congestion, inflammatory cell infiltration, and increase in apoptotic cells were found in ovary tissues in exposure groups. For male rats, the weights decreased gradually, the ratio of epididymis weight over body weight increased, the motility of rat sperm changed, and the levels of FSH and testosterone (T) diminished. Pathological results showed the shedding of epithelial cells of raw seminiferous tubule, disordered arrangement of cells in the tube, and the appearance of cell apoptosis and death in the exposure group. At the same time, Ni NPs resulted in a change of the reproductive index and the offspring development of rats. Further research is needed to elucidate exposure to human populations and mechanism of actions. 相似文献
44.
This article has been retracted because of prior acceptance by another publication. The publisher regrets any inconvenience this may have caused. 相似文献
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空间不对称希夫碱(HCBP-PHEN-SALH)的合成和表征 总被引:1,自引:0,他引:1
报道了用控制反应物配比的方法,合成空间不对称希夫碱5-氯-2-羟基二苯甲酮缩邻苯二胶缩水杨醛(HCBP-PHEN-SALH),用红外光谱和核磁共振进行了结构表征。 相似文献
47.
Carr Hoi Yi Ho Qi Dong Hang Yin Winky Wing Ki Leung Qingdan Yang Harrison Ka Hin Lee Sai Wing Tsang Shu Kong So 《Advanced Materials Interfaces》2015,2(12)
The effects of a solvent additive, 1,8‐diiodooctane (DIO), on both hole and electron transport are investigated in a state‐of‐the‐art bulk‐heterojunction (BHJ) system, namely PTB7:PC71BM. For a polymer:fullerene weight ratio of 1:1.5, the electron mobility in the blend film increases by two orders of magnitude with the DIO concentration while almost no change is found in the hole mobility. For lower DIO concentrations, the electron mobility is suppressed because of large, but poorly connected PC71BM domains. For higher concentrations of DIO, the electron mobility is improved progressively and the hole mobility becomes the limiting factor. Between 1 and 5 vol%, the electron and hole mobilities are balanced. Using the Gaussian disorder model (GDM), we found that the DIO concentration modifies fundamentally the average hopping distances of the electrons. In addition, there exist alternative donor–acceptor ratios to achieve optimized PTB7:PC71BM based solar cells. It is demonstrated that the fullerene content of the BHJ film can be significantly reduced from 1:1.5 to 1:1 while the optimized performance can still be preserved. 相似文献
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John H. Collins Seong-Hoon Yoon Deepak Musale Jian Feng Kong Jeroen Koppes Suma Sundararajan Shih-Perng Tsai G. Anders Hallsby Philippe Cachia & Karen Kronoveter 《Water and Environment Journal》2006,20(1):43-47
Recently developed polymeric membrane performance enhancer product, MPE50, was tested in various pilot‐ and full‐scale membrane bioreactors (MBRs). The Initial MPE50 dosage was determined by visual jar tests and by using various bench‐top filtration tests. Different amounts of MPE50 were dosed, and the particle size and supernatant clarity of the mixed liquor were monitored visually. Bench‐top filtration tests were also conducted. A 50% higher MPE50 dosage is recommended to be added to the pilot/full‐scale bioreactors because, based on experience, some of the soluble microbial products in the mixed liquor do not completely react with polymer during the relatively short bench‐test mixing time interval. With the addition of 400 mg/L MPE50 to a pilot MBR, the design flow was increased twofold without any significant transmembrane pressure (TMP) increase for 1 day. The control TMP surged within a few hours without MPE50. Long‐term field trials in a full‐scale plant also showed a substantial flux increase. In addition to flux enhancement, MPE50 helped to remove foam from the bioreactors and improved plant aesthetics, safety and general operating performance. 相似文献