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1.
成熟蕃茄匀浆后,经硫酸铵盐析,DEAE-SephadexA-50离子交换层析,SepadexG-100凝胶过滤和Melibiose-Agarose亲和层析,获得了α-D-半乳糖苷酶(C.E.3.2.1.11)。酶制剂经PAGE检测为一条带;SDS-G-PAGE测得酶Mr为34000;比活力52.9U/mg·;提纯倍数为52901产率为45%.酶专-催化以α-D-半乳糖为末端a-(1,3)连接的糖苷键,以PNPG(对硝基苯-α-D-半乳糖昔)为废物,酶催化反应的Km=0.11mmol/L,Vmax为67μmol·mg1-·min-1.t稳定范是0~35℃;PH稳定范围是4.0~7.0.最适pH为5.1.半乳糖是酶的竞争性抑制剂;Cu2+、Zn2+、Mn2+、Fe3+、Ag+和EDTA对酶活性无影响.纯酶制剂可作为B型血向O型血转化的工具酶液.  相似文献   

2.
不同菌源的微生物对邻苯二甲酸二甲酯生物降解性的比较   总被引:2,自引:0,他引:2  
从处理石化厂废水的活性污泥中分离出1 株邻苯二甲酸酯降解菌 F S1( 荧光假单胞菌 Pseudomonasfluorescens F S1) ,从处理焦化厂废水的活性污泥中分离出2 株邻苯二甲酸酯降解菌 F S2( 铜绿假单胞菌 Pseudomonasaeruginasa F S2) 和 F S3( 短杆菌 Brevibacterium sp . F S3) . 研究了邻苯二甲酸酯降解菌 F S1 , F S2 和 F S3 对邻苯二甲酸二甲酯( D M P) 的最适降解条件,比较了其降解特性. F S1 、 F S2 和 F S3 最适酸度分别为p H6 .5 ~8 .0 、p H7 .0 ~8 .0 和p H7 .0 ~8 .0 ,温度为20 ~35 ℃、15 ~35 ℃和15 ~35 ℃.邻苯二甲酸酯降解菌 F S1 、 F S2 和 F S3 对邻苯二甲酸二甲酯的降解的半寿期: F S1 < F S2 < F S3 ,邻苯二甲酸酯降解菌 F S1 是一株高效的邻苯二甲酸二甲酯降解菌  相似文献   

3.
盐胁迫下耐盐与盐敏感水稻的RAPD和POD同工酶检测   总被引:11,自引:0,他引:11  
对耐盐、一般耐盐和盐敏感3种水稻材料进行了RAPD和同工酶检测,结果发现:33个引物(N-1-N-12,S450-S470)中,27个引物具有拉增产物,拉增片段大小分布在0.2-3.4kb之间,说明在一定程度上反映了3种对盐具有不同耐盐性水稻在基因组DNA分子水平上的差异,以S450为引物,在强耐盐的779中扩增出1个1.1kb的特异DNA片段(S4501100),而在对盐敏感的早花2号中,以N-  相似文献   

4.
原生质体转化构建有机磷农药降解工程菌   总被引:5,自引:0,他引:5  
降解有机磷农药甲胺磷、敌敌畏和对硫磷的菌株地衣芽孢杆菌 P12( Bacilluslicheniformis) 经溶菌酶处理获得原生质体,加入降解乐果的供体菌 G1 D N A,经ρ( P E G6 000) = 300 g L- 1 诱导,在液体再生培养基中振荡培养t= 20 h ,使其恢复细胞壁后,离心收集菌体,涂布于含乐果的基础培养基上,经筛选得一转化子 J P Z.其菌落形态明显不同于出发菌株,乐果平板连续传代10 次,性状保持稳定.在θ= 30 ℃,100 r/min 的培养条件下,3 d 内对ρ( 甲胺磷) = 0 .5 g L- 1 ,ρ( 敌敌畏) = 0 .2 g L- 1 ,ρ( 对硫磷) = 0 .1 g L- 1 ,ρ( 乐果) = 0 .3 g L- 1 的降解率分别为 Rd = 79 .1 % ,46 .7 % ,29 .4 % 和46 .4 % .  相似文献   

5.
采用GC-MS方法对萘酚在超临界水中氧化降解的产物进行了分析和鉴别,通过对中间产物的鉴别并结合相关的研究,提出了萘酚在超临界水中氧化降解的路径.萘酚氧化降解的路径可用纵横交叉模式描述,即纵向的氧化开环降解反应和横向的偶合反应,萘酚及其带芳环的中间产物进一步氧化都经过苯酚,并由其继续开环氧化降解.  相似文献   

6.
PCDDs在氯仿溶液中的紫外光解   总被引:11,自引:1,他引:10  
包志成  郑明辉 《环境化学》1995,14(3):190-195
使用NDC-3型化学反应仪、300W汞灯和15ml反应管,于43℃进行了2,3,7,8-TCDD,1,2,3,7,8-P5CDD,1,2,3,4,7,8-HxCDD,1,2,3,4,6,7,8-HpCDD和OCDD在氯仿溶中的紫外光解,其一级反应速率常数测得值依次为0.54,0.29,0.15,0.15和0.19min^-1,反应半衰期t1/2均在5min以内,还原脱氯是主要的光解途径,并有大量低  相似文献   

7.
李国刚 《环境化学》1995,14(2):164-168
本文研究了在氨性介质中,Meso-四(4-磺基苯基)卟啉与锌离子的络合反应,在沸水浴中,该反应在4min内完成,并形成稳定的1:1型络合物,其峰电位为-1.35V(vs,SCE)将此络合吸附波用于环境水样中痕量锌的测定,获得了满意的结果,本文还对事物及卟啉试剂极谱波的性质做了比较研究。  相似文献   

8.
农药废水中的有机硫,磷污染物湿式空气氧化反应的研究   总被引:1,自引:1,他引:0  
王怡中  李忠 《环境化学》1993,12(5):415-419
以o,o-二甲氧基或o,o-二乙氧基硫代磷酰氯废水为典型废水,在180-230℃,氧气压力为0.7-1.5MPa的反应条件下,在2L的不锈钢的高压釜中,研究了农药废中有机硫磷化合物在温式空气氧化过程中的降解机制。实验结果表明,有机硫磷化合物分子中的有机硫通过氧化反应降解为硫,有机磷通过水解反应降解为磷酸。有机硫氧化生成的硫酸是废水湿式空气氧化程中酸度增加的主要来源。酸性条件比碱性条件更利于有机硫磷  相似文献   

9.
雨水中S(Ⅳ)的离子色谱分析及其保护方法的研究   总被引:3,自引:1,他引:3  
栗欣  郭花捷 《环境化学》1996,15(1):76-81
本文研究了用离子色谱法分析雨水中S(Ⅳ)的色谱条件和含S(Ⅳ)样品的保存方法,采用HPIC_ASA分离柱、用2mmol.l^-1Na2CO3/3mmol.l^01NaOH溶液作淋洗液、0.0125mol.l^-1H2SO4为再生液、电导检测的方法,具有无干扰和灵敏度高等优点,而且在S(Ⅵ)的浓度秋-28μg.ml^-1范围内,其浓度与响应值之间呈现出良好的线性关系,其线性相关系数在0.9995以上  相似文献   

10.
磷酸铁膜对黄铁矿氧化抑制作用   总被引:2,自引:1,他引:2  
黄骁  蓝叶青 《环境化学》1998,17(4):376-380
本文用动力学、表面分析方法研究在黄铁矿表面磷酸铁膜形成的可能性以及磷酸铁膜抑制黄铁矿的氧化作用,黄铁矿经0.3mol.l^-1H2O2+0.01mol.l^-1NaH2PO4+0.05mol.l^-1NaAc(ph5.0)淋洗后,在其表面可形成一层磷酸铁膜,该能显著抑制黄铁矿的进一步氧化,结果还表明,在H2O2作用下,黄铁矿氧化有自催化氧化的特征,其氧化产物Fe^3+能加快黄铁矿的氧化速率。  相似文献   

11.
黄磷诱发氧化破坏苯环结构的反应途径   总被引:4,自引:0,他引:4  
黄磷诱发氧化是一种有效的氧化新技术,对许多结构稳定的污染物有明显去除效果,本文针对四种典型苯基衍生物,初步考察了反应过程中原始物的去向。实验结果表明:因气液相接触条件的不同,苯环的三个双键可同时被打开生成乙酸,并进一步氧化到甲酸;或者只打开一个双键,生成共轭小分子羧酸。  相似文献   

12.
苯酚的超临界水氧化试验   总被引:4,自引:0,他引:4  
以自建的一套连续式超临界水氧化装置的温度,压力,溶氧量和流量等参数的可控性进行了实验,并在此基础上进行了苯酚的超临界水氧化研究。结果表明:所建立的装置能比较精确控制各种条件参数,是可靠的超临界水氧化试验研究装置。在氧气过量的条件下,停留时间是影响苯酚在超临界水中氧化分解的主要因素,反应的温度和压力升高导致苯致苯酚去除率的增大,只要有足够的氧气,苯酚起始浓度的增加对苯酚的转化率影响不明显,在实验条件下,溶液中苯酚的去除动力学对苯酚是一级,氧气是零级。  相似文献   

13.
Wet air oxidation (WAO) is one of effective technologies to eliminate hazardous, toxic and highly concentrated organic compounds in the wastewater. In the paper, multi-walled carbon nanotubes (MWCNTs), functionalized by O3, were used as catalysts in the absence of any metals to investigate the catalytic activity in the catalytic wet air oxidation (CWAO) of phenol, nitrobenzene (NB) and aniline at the mild operating conditions (reaction temperature of 155°C and total pressure of 2.5 MPa) in a batch reactor. The MWCNTs were characterized with scanning electron microscopy (SEM), transmission electron microscopy (TEM), gas adsorption measurements (BET), fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS). The functionalized MWCNTs showed good catalytic performance. In the CWAO of phenol over the functionalized MWCNTs, total phenol removal was obtained after 90 min run, and the reaction apparent activation energy was ca. 40 kJ·mol-1. The NB was not removed in the CWAO of single NB, while ca. 97% NB removal was obtained and 40% NB removal was attributed to the catalytic activity after 180 min run in the presence of phenol. Ca. 49% aniline conversion was achieved after 120 min run in the CWAO of aniline.  相似文献   

14.
活性炭的光催化再生机理   总被引:6,自引:0,他引:6  
通过研究催化剂的改性、再生温度、外加氧化剂对活性炭光催化再生反应速度的影响,结合光催化与活性炭的吸附理论,分析了活性炭的光催化再生机理.研究表明,活性炭的光催化再生由三个准一级反应组成.再生初期,再生反应速度由TiO2光催化降解吸附质的速率决定;反应的第二个阶段由光催化反应速度和吸附质的解吸速度共同决定;再生后期,再生反应速度由吸附质在活性炭上的解吸速率所决定.活性炭表面及其大孔内负载的Ti0:是使苯酚降解转化分解为无机物的降解中心.正是由于降解中心的存在及其表面苯酚浓度趋于零的状态,使得已吸附于活性炭孔内的苯酚不断向这个中心扩散,形成活性炭孔内苯酚的浓度差.在浓度差的作用下,扩散作用持续进行,导致活性炭内吸附位的逐步空出,从而实现活性炭的光催化再生.  相似文献   

15.
Aqueous solutions of phenol were oxidized by hydrogen peroxide assisted by microwave (MW) irradiation. A simple kinetic model for the overall degradation of phenol in the presence of excess H2O2 is proposed in which the degradation rate of phenol is expressed as a linear function of the concentrations of phenol and H2O2. A detailed parametric study showed that the degradation rate of phenol increased with increasing [H2O2] until saturation was observed. Phenol degradation followed apparent zero-order kinetics under MW radiation or H2O2 oxidation. However, after 90 min of irradiation, the observed kinetics shifted to pseudo first order. The overall reaction rates were significantly enhanced in the combined MW/H2O2 system, mainly because microwave could accelerate H2O2 to generate hydroxyl radical (·OH) and other reactive oxygen intermediates. The observed synergetic effects of the MW/H2O2 process resulted in an increased in the net reaction rate by a factor of 5.75. When hydrogen peroxide is present in a large stoichiometric excess, the time required to achieve complete mineralization is reduced significantly.  相似文献   

16.
几种天然矿物去除苯酚效果及日光光解效应评价   总被引:15,自引:0,他引:15  
郑红  汤鸿霄 《环境化学》1998,17(5):473-479
本文以四种天然矿物为受试矿物,评价了它们去除苯酚的效果,以及日光光解放应及温度,PH值,矿物浓度,苯酚初始浓度对去除效果的影响。  相似文献   

17.
The results of a study of photocatalytic degradation of phenol using aqueous oxygenated TiO2 (anatase) suspensions in a batch Pyrex photoreactor are reported. The influence on the photodegradation rate of various parameters as pH, phenol and TiO2 content, oxygen partial pressure, anions present in the dispersions was investigated. A complete oxidation of phenol was observed. Intermediate compounds, catechol and quinone, were detected. It was observed that the photodegradation also proceeded with sunlight radiation. A mechanistic and kinetic model, which accounts for the results obtained, is given. Likely reasons for inactivity of the rutile modification for this reaction are also given.  相似文献   

18.
原废水培养基分离活性污泥中的苯酚降解细菌   总被引:13,自引:0,他引:13  
用未经处理的含酚焦化工业废水为基础配制培养基,采用平板涂布法,在10^-5稀释度下得到100个单菌落分离物.它们均能在以苯酚(500-800mg L^-1)为唯一碳源的无机盐培养基上生长,其16S rDNA基因的ARDBA多态性分析将这些分离物划分成4个分类操作单元(OTUs).各单元代表株的16S rRNA基因序列分析和检索结果表明,97个分离物与Alcaligenes faecalis同源性达99%,2个分离物分别与Arthrobacter nicotianae和Klebsiella sp.99%同源.另一个分离物与Ochrobactrum sp.96%同源.苯酚经化酶大亚基基因(LmPHs)PCR扩增表明,除类似Arthrobacter nicotianae的菌株外,其它3个分类操作单元的降酚菌都能利用多组分苯酚经化酶代谢途径进行酚代谢.图2表2参11  相似文献   

19.
As a green oxidant, permanganate has received considerable attention for the removal of micropollutants in drinking water treatment. To provide a better understanding of the oxidation of organic micropollutants with permanganate, the oxidation kinetics of 32 micropollutants were compiled. The pollutants include algal toxins, endocrine disrupting chemicals (EDCs), and pharmaceuticals. The oxidation kinetics of micropollutants by permanganate were found to be first order with respect to both contaminant and permanganate concentrations from which second-order rate constants (k″) were obtained. Permanganate oxidized the heterocyclic aromatics with vinyl moiety (i.e., microcystins, carbamazepine, and dichlorvos) by the addition of double bonds. For the polycyclic aromatic hydrocarbons (PAHs) with alkyl groups, permanganate attacked the benzylic C-H through abstraction of hydrogen. The mechanism for the oxidation of phenolic EDCs by permanganate was a single electron transfer and aromatic ring cleavage. The presence of background matrices could enhance the oxidation of some phenolic EDCs by permanganate, including phenol, chlorinated phenols, bisphenol A, and trichlosan. The toxicity of dichlorvos solution increased after permanganate oxidation, and the estrogenic activity of bisphnol A/estrone increased significantly at the beginning of permanganate oxidation. Therefore, the toxicity of degradation products or intermediates should be determined in the permanganate oxidation processes to better evaluate the applicability of permanganate. The influence of background ions on the permanganate oxidation process is far from clear and should be elucidated in the future studies to better predict the performance of permanganate oxidation of micropollutants. Moreover, methods should be employed to catalyze the permanganate oxidation process to achieve better removal of micropollutants.  相似文献   

20.
二段生物接触氧化法处理含硫废水的中试研究   总被引:3,自引:0,他引:3  
用二段生物接触氧化法探索炼油过程中所产生的含硫废水的处理新方法. 结果表明:经此工艺处理后的出水 C O D、氨氮、硫化物和酚的质量浓度ρ分别为266 .9 mg/ L、82 .85 mg/ L、1 .18 mg/ L 和1 .43 mg/ L,相应的去除率分别为86 .3 % 、40 % 、92 .7 % 和99 .3 % ,出水水质达到国家三级排放标准. 进出水水质的变化曲线表明,生物接触氧化法处理含硫废水对进水水质变化的适应能力比较强,出水水质比较稳定,显示了二段接触氧化法处理含硫废水的可行性  相似文献   

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