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51.
水合肼生产盐渣中氮化合物的去除 总被引:1,自引:1,他引:0
将水合肼生产盐渣分离碳酸钠后,通过吹脱、氧化等工艺降低饱和盐溶液的氮含量(以氨质量浓度计),以达到电解法制备氢氧化钠工艺对原料氯化钠的使用要求。中试试验结果表明:氧化反应最佳工艺条件为以次氯酸钠为氧化剂,次氯酸钠溶液中氢氧化钠质量浓度9.2g/L,次氯酸钠与初始氨的质量比为13,溶液pH 7~8,反应温度30~35℃;在此条件下氧化处理饱和盐溶液,处理后氨质量浓度由350.0 mg/L降至2.1 mg/L。将处理后的饱和盐溶液用于电解法制备氢氧化钠的生产过程,不仅可创造一定的经济效益,而且还解决了水合肼生产中的环境污染问题。 相似文献
52.
固定化白腐真菌反应器与接触氧化反应器联用处理癸二酸生产废水 总被引:1,自引:1,他引:0
采用固定化白腐真菌(WRF)反应器与接触氧化反应器联用处理癸二酸废水。在WRF反应器中,以汽曝玉米秸秆为载体,并添加铜、铁促进白腐真菌生长和产酶作用,载体的使用寿命约为45 d。在进水苯酚平均质量浓度为69.36 mg/L、平均进水COD为1 648.81 mg/L的条件下,经WRF反应器处理后,苯酚平均质量浓度降至7.59 mg/L,平均出水COD降至478.03 mg/L;再经接触氧化反应器处理后,苯酚平均质量浓度降至1.65 mg/L,平均出水COD降至297.31 mg/L。 相似文献
53.
外循环厌氧处理工艺中布水和三相分离的改进研究 总被引:1,自引:0,他引:1
污水处理中的布水设备和三相分离设备存在很多缺点,通过旋流配水装置和传统配水装置、小间距斜板三相分离装置和传统三相分离装置的比较试验,研究了旋流配水装置和小间距斜板三相分离装置的性能.研究结果表明:在相同膨胀率的条件下,旋流配水装置所需的回流量小,能耗相对较少;在水力上升流速为8 m/h时,采用旋流配水装置进水时,污泥分布曲线较平缓,污泥在高度上分布较均匀,而采用传统配水装置进水时,污泥主要分布在反应器底部,污泥浓度分布不均匀;在上升流速相同的情况下,采用小间距三相分离装置的反应器出水携带的颗粒污泥浓度较小;在相同的进水COD浓度时,小间距三相分离装置分离的沼气量较多.改进的布水和三相分离装置的性能明显优于传统的布水和三相分离装置. 相似文献
54.
脱硫脱硫弧菌转化二氧化硫气体的研究 总被引:1,自引:0,他引:1
运用连续处理工艺研究了SO_2进气摩尔流速和去除率的关系,并对主要转化产物硫化氢和硫化物进行了测定,研究了亚硫酸盐的积累情况及其对脱硫脱硫弧菌生长的影响,同时还对碳源的消耗及转化产物进行了定量研究.实验结果表明,随着SO_2流速的提高(4·975~20·149mmol·h~(-1))菌体对二氧化硫的去除率没有发生明显的变化,始终保持在93%以上,在SO2摩尔流速低于5·034mmol·h~(-1)时产物以硫化氢为主,而随着SO_2摩尔流速的提高,液相中硫化物和亚硫酸盐开始累积;当SO_2摩尔流速增大至20·149mmol·h~(-1)时,亚硫酸盐累积浓度达到74·23mg·L~(-1),该浓度对菌体生长不会产生抑制作用;系统在SO_2摩尔流速为14·063mmol·h~(-1)下运行时较为稳定,乳酸盐全部转化为乙酸盐,每还原1mmol SO_2消耗0·4mmol CH_3CHOHCOO~-. 相似文献
55.
This study examined the relationships between culture, individual attributes, and self‐rating behavior among 1,786 university students in Canada, Hong Kong, Taiwan, mainland China, and Japan, and in doing so extended and refined the cultural relativity hypothesis. It explored the difference between vertical and horizontal individualists in self‐rating behavior, and examined the mediating effects of two individual attributes, self‐enhancement propensity and general self‐efficacy in the relationship between individualism and self‐rating behavior. The results confirmed that individualism is the cultural driver for self‐rating leniency, and that the individual‐level assessment of individualism is a stronger predictor of self‐rating leniency than are culture‐level differences. Vertical individualism was found to be positively related to self‐enhancement propensity, which in turn was positively related to self‐rating. Whereas, horizontal individualism was positively related to general self‐efficacy, which in turn had a positive relationship with self‐rating. We discuss the implications of the results for academic research and practical management. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
56.
用人单位在招退工过程中,作为劳动保障部门的行政控制权究竟处于什么样的水平才是合适的,这一直是各地司法实践中所关注的问题.由于我国《劳动法》对这一问题没有作出明确规定,使得我国地方立法有了较大的空间. 相似文献
57.
Qiuqing Geng Fang Chen Ingvar Holmér 《International journal of occupational safety and ergonomics》2013,19(1-2):15-29
This article presents a study on the effect of different protective gloves (which are commercially available and commonly used in the cold) on manual dexterity in cold environments. The experiments compared statistically four different types of gloves and two different types of gloving (outer or double) at +19 °C and -10 °C. Performance was determined both objectively and subjectively using two manual dexterity tasks: bolt-nut and pick-up tasks. The response measured was the time of performing each task. Statistical analysis showed that all independent factors such as glove type, participant, object size, and temperature had significant effects on the hand cooling reaction. A significant difference in the performance between the gloves was found in the bolt-nut task. It was also found that outer-inner combination gloving may be an approach to use for precision tasks. 相似文献
58.
Weidong Li Shiqi Li Jacon Chen 《International journal of occupational safety and ergonomics》2013,19(1):21-32
Different from walking, ladder climbing requires four-limb coordination and more energy exertion for below-knee amputees (BKAs). We hypothesized that functional deficiency of a disabled limb shall be compensated by the other three intact limbs, showing an asymmetry pattern among limbs. Hand and foot forces of six below-knee amputees and six able-bodied people were collected. Hand, foot and hand/foot sum force variances between groups (non-BKA, intact side and prosthetic side) were carefully examined. Our hypothesis was validated that there is asymmetry between prosthetic and intact side. Results further showed that the ipsilateral hand of the prosthetic leg is stronger than the hand on the intact side, compensating weakness of the prosthetic leg. Effects of ladder rung separations and ladder slant on asymmetric force distribution of BKAs were evaluated, indicating that rung separation has a more significant interactive effect on hand/foot force of BKAs than ladder slant. 相似文献
59.
An integrated process of metal chelate absorption coupled with two stage bio-reduction using immobilized cultures has been proposed to continuously removal of NOx, and the effects of SO2, NO and O2 concentration, gas/liquid flow rate on NOx removal efficiency were investigated. Although nitrogen-containing components, such as Fe(II)EDTA-NO, NO2? and NO3? in the scrubbing solution, inhibited the bio-reduction of Fe(III)EDTA obviously, it was feasible to abate the inhibition effect by using the two stage bio-reduction system, and thus to improve NOx removal efficiency. The removal efficiency decreased slowly with the increase of SO2, O2, NO concentration and gas flow rate, and increased with the increase of liquid flow rate. Continuously operating for 18 days, a high removal efficiency around 95% was reached by using the two-stage bio-reduction system with immobilized microorganisms, while the value decreased to 85% after 5 days of operation by using the suspended microorganisms, at a constant gas flow rate of 60 L/h containing 424–450 mg/m3 NO, 2428–2532 mg/m3 SO2 and 3% O2. 相似文献
60.
随着化工园区重大危险源集中监管的深化,政府和企业在安全生产活动中扮演着比以往更重要的角色.如何降低园区内人群对危险源的敏感性,以便在有谣言时不会伴随更大的混乱;什么样的因素对园区内人群认知风险具有显著相关性,以便政府和企业在安全生产活动中更好地发挥职能.针对上述问题,通过对江西省某化工园区进行问卷调查,所得的数据采用累积logistic模型进行分析,得出对风险认知具有显著性差异的因素.有助于政府及企业管理人员对园区内人群认知风险的了解,建议化工园区以及政府需要进一步宣传安全知识,配套安全设备等,最终降低谣言对生产活动的影响、冲击,稳定社会秩序. 相似文献