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81.
介绍蓝法法工艺技术综合治理高浓度含氰废水过程,将废水含CN^-浓度由几千mg/L降至2mg/L左右,并回收含CN^-物质制取黄血盐医药产品,取得较好的经济效益。  相似文献   
82.
The media from primary cultures and subcultures of second trimester human amniotic fluid (AF) cells were assayed by radioimmunoassay to quantitate production of human chorionic gonadotropin (hCG). Primary AF cultures produce more hCG per cell than do the corresponding subcultures. Sodium butyrate (2 mM) stimulates AF subcultures to produce 5-13 times more hCG per cell or per mg of cellular protein than do untreated subcultures. This stimulatory effect of sodium butyrate is dose dependent between 0 and 5 mM. Addition of sodium butyrate 24 hours after subculture, while stimulating production of hCG during the subsequent 3 days, also results in fewer cells and less protein per culture. This effect on cell growth is also dose-dependent. Previous investigators have proposed that the stimulation of hCG by sodium butyrate in other types of cell cultures is due to an effect of that agent on culture growth. Therefore, in these studies AF cells are allowed to grow to confluency before sodium butyrate was added. Production of hCG was stimulated by sodium butyrate about four-fold during the next 5 days although no significant changes were observed either in number of cells or amount of cellular protein per culture. These results suggest that stimulation of hCG by sodium butyrate is not dependent on its effect on growth of the cultures.  相似文献   
83.
含铵,钠和铁盐废水处理的方法   总被引:2,自引:0,他引:2  
介绍了国内外处理不同浓度含铵、钠和铁盐废水的实用技术与动态。力求为废水处理和资源回收提供参考。  相似文献   
84.
利用二室阳离子膜电解装置,以亚硫酸钠和亚硫酸氢钠溶液模拟钠碱烟气脱硫吸收富液,进行吸收液再生规律的研究。实验考察了流体流速和槽压对膜电解过程的影响,明确了其相关规律,确定了较佳操作参数。研究结果证明:增大槽压和流体流速有利于脱硫富液的电解再生,而且钠离子浓度越低电解再生越容易。同时,实验中注意到电解过程中溶液伴渗对电流效率和钠离子迁移率有较大的影响。  相似文献   
85.
在pH值大于9和温度为25.0±0.01℃条件下,采用pH值探针技术研究二氧化氯氧化硫代硫酸钠反应体系在封闭搅拌状态下的动力学行为,结果表明,在封闭条件下体系的pH值呈现比较复杂的准振荡现象,大致经过四个阶段(Ⅰ,Ⅱ,Ⅲ,Ⅳ)的下降:(Ⅰ)下降来源于二氧化氯的自身歧化反应动力学;(Ⅱ)下降来源于连四硫酸钠的水解反应动力学;(Ⅲ)下降来源于硫代硫酸钠被二氧化氯氧化的主反应动力学;(Ⅳ)下降来源于ClO-2和ClO2与连四硫酸钠及其水解产物的反应动力学.其中,连四硫酸钠的碱性水解反应是pH值动力学的关键.  相似文献   
86.
In this study,sodium tripolyphosphate(STPP) was used to promote the removal of organic pollutants in a zero-valent copper(ZVC)/O_2 system under neutral conditions for the first time.20 mg/L p-nitrophenol(PNP) can be completely decomposed within 120 min in the ZVC/O_2/STPP system.The PNP degradation process followed pseudo-first-order kinetics and the degradation rate of PNP gradually increased upon the decreasing ZVC particle size.The optimal pH of the reaction system was 5.0.Our mechanism investigation showed that Cu~+generated by ZVC corrosion was the main reducing agent for the activation of 02 to produce ROS.-OH was identified as the only ROS formed during the degradation of PNP and its production pathway was the double-electron activation of O_2(O_2→H_2 O_2→·OH).In this process,STPP did not only promote the release of Cu~+through its complexation,but also promoted the production of OH by reducing the redox potential of Cu~(2+)/Cu~+.In addition,we could initiate and terminate the reaction by controlling the pH.At pH 8.1,ZVC/02/STPP could continuously degrade organic pollutants;at pH 8.1,the reaction was terminated.STPP was recycled to continuously promote the corrosion of ZVC and O_2 activation as long as the pH was 8.1.This study provided a new and efficient way for O_2 activation and organic contaminants removal.  相似文献   
87.
The effect of salinity on sludge alkaline fermentation at low temperature(20°C) was investigated, and a kinetic analysis was performed. Different doses of sodium chloride(Na Cl, 0–25 g/L) were added into the fermentation system. The batch-mode results showed that the soluble chemical oxygen demand(SCOD) increased with salinity. The hydrolysate(soluble protein, polysaccharide) and the acidification products(short chain fatty acids(SCFAs), NH+4–N, and PO_4~(3-)–P) increased with salinity initially, but slightly declined respectively at higher level salinity(20 g/L or 20–25 g/L). However, the hydrolytic acidification performance increased in the presence of salt compared to that without salt.Furthermore, the results of Haldane inhibition kinetics analysis showed that the salt enhanced the hydrolysis rate of particulate organic matter from sludge particulate and the specific utilization of hydrolysate, and decreased the specific utilization of SCFAs. Pearson correlation coefficient analysis indicated that the importance of polysaccharide on the accumulation of SCFAs was reduced with salt addition, but the importance of protein and NH+4–N on SCFA accumulation was increased.  相似文献   
88.
高分子凝胶球去除废水中重金属离子的研究   总被引:6,自引:2,他引:4  
用海藻酸钠(SA)、海藻酸钠-聚乙烯醇(SA—PVA)、海藻酸钠-聚氧化乙烯(SA—PEO)凝胶球作为吸附剂吸附溶液中的Pb^2+。探讨了凝胶球固定化时间、吸附时间、溶液pH值、溶液初始浓度对Pb^2+去除率的影响,并对吸附动力学方程进行了分析。结果表明:固定化时间对去除率的影响较小;反应速率较快,吸附时间在10min时,三种凝胶球对Pb^2+的去除率就分剐达到了80%、82%和88%,吸附时间在2h后基本达到吸附平衡,三种凝胶球对Pb^2+的吸附能力为:SA—PGE〉SA—PVA〉SA;三种凝胶球吸附铅离子的行为均符合一级反应动力学方程;溶液的pH在4~6时有较高的去除率;三种凝胶球对不同金属的吸附能力为Pb^2+〉Cu^2+〉Cd^2+;饱和吸附后的三种凝胶球均可以再生利用。  相似文献   
89.
海藻酸钠-钙-铁凝胶球对Cr_2O_7~(2-)吸附的研究   总被引:1,自引:0,他引:1  
本实验对海藻酸钠在氯化钙、氯化铁溶液中的成球特性,以及对SA-Ca、SA-Fe、SA-Ca-Fe凝胶球吸附Cr2O72-特性进行了研究。结果表明,SA-Ca凝胶球对Cr2O72-没有吸附能力,SA-Fe和SA-Ca-Fe凝胶球对Cr2O72-去除率均达到97%以上,但SA-Fe凝胶球成球性差,机械强度低,易碎。SA-Ca-Fe凝胶球吸附Cr2O72-符合Langmuir型,其最大吸附量为13.497mg/g。吸附属于单分子层吸附,凝胶球网络中的Fe3+与溶液中Cr2O72-发生化学反应,生成Fe2(Cr2O7)3。  相似文献   
90.
燃煤烟气脱硫石膏在新疆盐碱土壤改良中的应用研究   总被引:5,自引:0,他引:5  
以燃煤烟气脱硫石膏作为化学改良剂,在新疆克拉玛依地区进行碱化土壤改良,土壤改良后种植新疆杨(Populus bolleana Lauche)、白榆(Ulmus pumila L.)、沙棘(Hippohgae rhamnoides L)。分析了烟气脱硫石膏对盐碱地土壤理化性质和树木生长状况的影响。结果表明:处理区土壤的pH值和全盐量比对照区有明显降低,处理区的原始碱化度越高,改良后碱化度的下降幅度越大,而且表层土壤中碱化度的下降最为明显,从29.9%下降到1.43%。改良后树木的平均成活率为71%,比对照区树木的成活率高41%,用燃煤烟气脱硫石膏改良新疆克拉玛依地区碱化土壤种植树木具有极大的推广应用价值。  相似文献   
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