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1.
一、液氯、氯水的成分辨析液氯是氯气单质的液态,是纯净物,只含有氯气分子,只能体现氯气的性质.将氯气溶于水得到氯水,氯气在水中的溶解度不大,因此在新制的氯水中主要存在氯气分子.溶于水的氯气分子只有少部分与水发生反  相似文献   

2.
1强氧化剂。氧化细菌内活性基因1)液氯氯气与水反应产生具有强氧化性的次氯酸,它能穿过细胞膜,减弱酶活性,甚至使其丧失,因而可杀死水中的病菌,自来水常用氯气消毒杀菌.  相似文献   

3.
从氯气的性质、危害谈起,论述利用氯气变害为宝。要正确认识氯气的危害,才能熟练驾驭氯气,使之更好地为人民服务。为此,提出对废旧液氯钢瓶采取安全处置方法的建议。  相似文献   

4.
离子色谱法测定饮用水中钠、镁、钙   总被引:1,自引:0,他引:1  
本研究了离子色谱法测定饮用水及源水中钠、镁、钙离子的方法。实验表明,该方法灵敏度高,重现性好,操作简便,分析快速。在本方法实验条件下.钠、镁、钙方法检出限,分别为:0.013mg/L;0.013mg/L;0.025mg/L。相对标准偏差分布在0.07-0.76%,加标回收率分布在99-102%。  相似文献   

5.
在生产、存储、运输和使用过程中,氯气的泄漏会危害健康和污染环境。文章在分析普通液氯阀泄漏原因的基础上,设计了新型波纹管液氯阀。该设计采用波纹管密封,阀杆上密封和填料密封,形成三道密封;并采用自动环缝焊接技术,以确保阀体、阀盖、波纹管之间焊接均匀牢固。设计的新型波纹管液氯阀在使用中实现了零泄漏,达到了安全、高效、免维护的工况要求。  相似文献   

6.
利用组织培养方法建立植物快速繁殖体系能很好地保存种质资源。该研究以矮晚柚无菌苗茎尖及子叶节为试验材料,采用正交设计L9,研究基本培养基、激素配比对腋芽萌发、芽增殖及壮苗的影响。结果表明:最适材料为无茵苗子叶节,最佳腋芽诱导方案为I/2MS+6-BA0.5mg/L+NAA0.05mg/L+GA31.0mg/L,丛生单芽在增值培养基1/2MS+6-BA0.5mg/L+NAA0.05mg/L的平均增殖系数达到5.8,最佳壮苗培养基为1/2MS+6-BAO.5mg/L+NAA0.1mg/L。  相似文献   

7.
教学过程的实施 首先创设情境:播放江苏淮安发生液氯泄露事故的有关报道(从发生到人畜中毒情况)。由此情境可以看出:此次液氯泄露事故给人民的生命和财产造成了重大损失!并讲授:一战和抗日战争中氯气的使用给人类带来了更加深重的灾难!这样,一方面加深了学生对氯气毒性的认识,  相似文献   

8.
采用共沉淀法以不同的Mg^2+、Al^3+与Cu^2+摩尔比制备一系列的镁铝铜三元类水滑石(Cu/Mg/Al—HTLc)。并研究了镁铝铜类水滑石的焙烧产(HTLc-500)对阴离子染料茜素黄GG的吸附特征。分别考察了不同镁铝铜摩尔比的HTLc-500、吸附剂投放量、反应温度、染料的初始浓度等因素对HTLc-500吸附阴离子染料茜素黄GG的影响。结果表明,对于合有20mg/L的茜素黄GG模拟废水溶液,镁铝铜摩尔比为8:10:22的类水滑石,投放量为25mg。在25℃下反应360min。去除率可达到99.14%。  相似文献   

9.
以不同浓度的α-NAA、GA3和玉米素处理离体的蜀葵叶片,发现0.5mg/L以下的α-NAA溶液和0.3mg/L以下的GA3溶液对其有延缓衰老的作用,0.5mg/L以上的α-NAA溶液和0.3mg/L以上的GA3溶液对其有促进衰老的作用,玉米素对其延缓衰老或者促进衰老的作用均不明显.  相似文献   

10.
以不同浓度的α-NAA、GA3和玉米索处理离体的蜀葵叶片.发现0.5mg/L以下的α-NAA溶液和0.3mg/L以下的GA3溶液对其有延缓衰老的作用.0.5mg/L以上的α-NAA溶液和0.3mg/L以上的GA3溶液对其有促进衰老的作用.玉米素对其延缓衰老或促进衰老的作用均不明显。  相似文献   

11.
当传统的3P词汇教学模式受到抨击后,新的词汇教学理念纷纷涌现,但高职学生并未因此而从如何记忆词汇的困惑中解放出来。笔者在多年的词汇教学中,通过研究学生课堂学习和自主学习词汇的过程和结果,总结出了一些适合高职学生的词汇教学方法。  相似文献   

12.
We evaluated several different pre-oxidation treatments, namely the introduction of either potassium permanganate (KMnO4), chlorine (Cl2), or both to remove manganese (Mn) from the Qiantang River source water. Our results showed that Mn removal percentages were 12.7%, 71.0%, 17.4% and 58.7% when none of the oxidants, KMnO4 only, Cl2 only, or both oxidants were added, respectively. Furthermore, a field study showed that when the available Mn concentration in the source water was 0.14 mg/L, it could be reduced to less than 0.05 mg/L when a solution of KMnO4 (0.47 mg/L) was added as the oxidant.  相似文献   

13.
INTRODUCTION Eutrophication of surface water is a significantly increasing worldwide problem (Ma and Liu, 2002). Mesocyclops leukarti, a kind of Cyclops, is a water-borne animal propagating prolifically in eutrophic water reservoirs or fresh water lakes in China. Some reservoirs such as Dahuofang Reservoir (Liaoning Province), East Taihu Lake (Jiangsu Province), Gaozhou, Qiyeshi and Xinfengjiang Reservoir (Guangdong Province), Miyun Reservoir (Beijing), etc. are sources of drinki…  相似文献   

14.
采用自制的活性氧化镁[XMgO.YMg(OH)2]对含氟饮用水进行除氟处理,试验表明:活化温度设定为440℃,煅烧中间产物碱式碳酸镁[Mg5(CO3)4(OH).24H2O]1.5h所得活性氧化镁0.3g投入100ml 5mg/L的含氟水,处理40min可使F-降至0.06mg/L;当活化温度设定430℃,保温1.5h时,0.4g的活性氧化镁处理pH=5~8的含氟水,净化后水含氟量为0.16~0.44 mgF-/L,除氟容量为1.21~1.14 mgF-/g,pH保持在8~9,有益于人体健康;当含氟水pH=9时,除氟容量降至0.51 mgF-/g;而当含氟水pH=3~4时,不适宜用活性氧化镁除氟.当原水浓度为12.5mgF-/L时,除氟容量为2.33mgF-/g,这个值高于文献中以层析硅胶为载体,活性氧化镁为吸附质,动态除氟容量1.72mgF-/g.  相似文献   

15.
以工业废渣钡渣为水处理剂,研究钡渣对水中磷去除率的影响,进水含磷10 mg/L,钡渣投加量5 g,处理时间90 min,pH为11时,去除率达81.9%.实验表明,钡渣与氢氧化钙协同作用去除水中磷时,去除率高于钡渣或氢氧化钙单独作用的处理效果.投加比例为(钡渣1 g+氢氧化钙1.5 g)/1 mg磷,水中磷的去除率达到90.42%,出水含磷量已经降低到1 mg/L以下,达到国家排放标准.去除率随着pH提高而增加.  相似文献   

16.
Removal of cyclops in pre-oxidizing cooperation water treatment process   总被引:1,自引:0,他引:1  
Zooplankton cyclops propagates profusely in waterbody, cannot be effectively inactivated by conventional disinfec- tion process, and becomes a troublesome drinking water treatment problem. In this work, the qualitative and quantitative ex- perimental studies were carried out on inactivation of zooplankton cyclops using oxidants, such as chlorine (Cl2), chlorine dioxide (ClO2), ozone (O3), hydrogen peroxide (H2O2), ozone/hydrogen peroxide (O3/H2O2), chloramines (Cl2-NH3) and potassium permanganate (KMnO4). The influences of various factors include different oxidant dosages, organic substance contents and pH values. The results showed that currently available oxidants used all might inactivate cyclops in some extent. According to the experimental results, chlorine dioxide, ozone, ozone/hydrogen peroxide and chloramines can be selected as effective oxidants for inactivating cyclops because of their strong inactivation abilities. Then the synergic removal effects on cyclops with ozone, ozone/hydrogen peroxide pre-oxidation followed by conventional water treatment processes were investigated. The results showed that ozone and ozone/hydrogen peroxide pre-oxidation can inactivate cyclops effectively, which then can be removed thoroughly by conventional water treatment processes. Cyclops cannot appear in water after filtration with 1.65 mg/L of ozone and 6 mg/L of hydrogen peroxide, with the inactivation rate being 62% before conventional water treatment processes. Cyclops cannot appear in water after filtration with 1.8 mg/L of ozone, with the inactivation rate being 50% before conventional water treatment processes. For different oxidants, when removal rate was the best, the inactivation rate was not the same. These results may pro- vide reference and model for actual waterworks.  相似文献   

17.
实验选择四溴二苯醚(BDE-47)与高氯酸盐(PER)作为研究对象,系统研究了二者联合暴露对成年斑马鱼肝脏抗氧化系统的影响。实验设置(BDE-47 8.5+PER 335) mg/L,(BDE-47 0.85+PER 33.5) mg/L,(BDE-47 0.085+PER 3.35) mg/L三种联合暴露组及二者各自单一的暴露组。暴露14天后,分别测定雌雄斑马鱼肝脏内超氧化物歧化酶(SOD)活性、过氧化氢酶(CAT)活性、谷胱甘肽过氧化物酶(Gpx)活性以及脂质过氧化物(MDA)水平。结果显示,与两种物质单一暴露相比,联合暴露致使肝脏内SOD,CAT的活性增加,MDA水平增加,而GSH活性降低,实验说明,PER诱导加剧了BDE-47对成年斑马鱼肝脏抗氧化酶的影响,进一步产生了氧化应激。  相似文献   

18.
以木麻黄叶状枝粉末作为生物吸附剂,研究其对重金属离子Cr(Ⅵ)的吸附性能和吸附规律,并探讨了溶液酸度、振荡时间、溶液初始浓度、吸附剂用量等因素的影响.结果表明,在吸附剂用量为0.3g、pH值为1、Cr(Ⅵ)初始浓度小于100mg/L、吸附时间为90min的条件下,相应的吸附容量和吸附率可达3.98mg/g和99.9%,残余的Cr(Ⅵ)浓度小于0.5mg/L,达国家工业废水排放标准GB18918-2002;正交实验结果表明,影响木麻黄吸附剂对Cr(Ⅵ)吸附效果的主次因素顺序为pH值〉吸附振荡时间〉吸附剂用量〉吸附液浓度.  相似文献   

19.
Li  Kai  Fan  Qun  Chuai  Hongyuan  Liu  Hai  Zhang  Sheng  Ma  Xinbin 《天津大学学报(英文版)》2021,27(3):202-216

As an energy-intensive industry, the chlor-alkali process has caused numerous environmental issues due to heavy electricity consumption and pollution. Chlor-alkali industry has been upgraded from mercury, diaphragm electrolytic cell, to ion exchange membrane (IEM) electrolytic cells. However, several challenges, such as the selectivity of the anodic reaction, sluggish kinetics of alkaline hydrogen evolution, degradation of membranes, the reasonable design of electrolytic cell structure, remain to be addressed. For these reasons, this paper mainly reviews the research progress of the chlor-alkali industry from materials to devices, including hydrogen evolution anode, chlorine evolution cathode, IEM, and electrolytic cell system. Finally, the research directions and prospects in the chlor-alkali industry are proposed for its further improvement.

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20.
为研究祁术的组织培养及快速繁殖技术,选用祁术的叶片和下胚轴为外植体材料,接种于附加植物生长调节剂NAA,6-BA及其组合的MS固体培养基上.结果表明:下胚轴为外植体明显好于叶片,对于愈伤组织形成,叶片采用MS NAA(0.5mg/L) 6-BA(2mg/L);下胚轴MS NAA(0.5mg/L) 6-BA(2mg/L);MS NAA(0.5mg/L) 6-BA(1mg/L)为宜.对于叶片丛生芽愈伤组织培养基用MS NAA(0.2mg/L) 6-BA(2.8mg/L),下胚轴丛生芽愈伤组织培养基用MS NAA(0.01mg/L) 6-BA(0.1mg/L);MS NAA(0.05mg/L) 6-BA(0.1mg/L)为宜,诱导生根以1/2MS NAA0.3mg/L最佳,生根率达95%以上.  相似文献   

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