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111.
关州水电站位于较为偏僻的丹巴县境内,工程所在地没有合格的粘土,只能使用外运的膨润土作为防渗墙固壁泥浆的原料,工程成本很高。冲击钻机施工防渗墙的泥浆净化回收利用存在较大的难度。因此进行了冲击钻机施工防渗墙的泥浆净化回收利用技术的研究,应用效果良好,显著节约了泥浆成本。  相似文献   
112.
A thermostable superoxide dismutase (SOD) from the inshore thermophile Thermus sp. JM1 was purified to homogeneity by steps of fractional ammonium sulfate precipitation, DEAE-Sepharose chromatography and Phenyl-Sepharose chromatography. The specific activity of the purified native enzyme was 1 656 U/mg. A sod gene from this strain was cloned and overexpressed in Escherichia coli (E. coli). The prepared apo-enzyme of the purified recombinant SOD (rSOD) was reconstituted with either Fe or Mn by means of incubation with appropriate metal salts. As a result, only Mn 2+ - reconstituted rSOD (Mn-rSOD) exhibited the specific activity of 1 598 U/mg. SOD from Thermus sp. JM1 was Mn-SOD, judging by the specific activities analysis of Fe or Mn reconstituted rSODs and the insensitivity of the native SOD to both cyanide and H 2 O 2 . Both the native SOD and Mn- rSOD were determined to be homotetramers with monomeric molecular mass of 26 kDa and 27.5 kDa, respectively. They had high thermostability at 50 ° C and 60 ° C, and showed striking stability across a wide pH span from 4.0 to 11.0.  相似文献   
113.
试验研究分毒素累积和解毒两个阶段,丈蛤(Meretrix meretrix)对麻痹性贝毒(Paralytic Shellfish Poisoning,PSP)的累积能力试验中每天投喂一定量塔玛亚历山大藻(Alexandrium tamarense),定期测定丈蛤体内的毒素含量;解毒试验通过投喂饵料和水体消毒的“内排外解...  相似文献   
114.
由黄海底泥分离得到1株能够稳定高产蛋白酶的菌株,命名为HW08.对该菌株进行形态特征、生理生化分析表明,其为革兰氏阴性杆菌,极生单鞭毛,非发酵型,严格需氧,细胞内不积累多羟基丁酸作为储藏碳源,氧化酶阴性.将该菌16S rDNA序列(GenBank登录号FJ999660)和假单胞菌属中模式菌株16S rDNA序列进行比对...  相似文献   
115.
Acetylcholinesterase (AChE) plays an important role in enzyme-based detection of pesticides in the environment. In this paper, AChE from the Triton X-100 extract of brain tissues of Oreochromis aurea was purified by (NH4)2SO4 fractional precipitation, Sephadex G-100 gel filtration, and DEAE-cellulose ion exchange chromatography. Certain biochemical characterizations of the purified enzyme and inhibition of pesticides on the enzyme were also studied. The specific activity of this purified enzyme was 20.628 U/mg protein, fold of purification was 139, and recovery was 22.1%. The optimal temperature of this enzyme was between 35–40 °C, and optimal pH was between 7.5–8.0. The Michaelis constant (Km) for acetylthiocholine iodide was 0.183 mmol/L. The enzyme activity was inhibited by excess substrate, and optimal substrate concentration was 6 mmol/L. Four pesticides (dichlorvos, phoxim, triazophos, and methomyl) exhibited strong inhibitions on this enzyme with IC50 less than 5 μg/mL. This study suggests that Oreochromis aurea (tilapia) could be a good enzyme source for pesticide monitoring in water environments.  相似文献   
116.
Surface patterns of the low-frequency current in a 20 × 30 km region in front of the Venice Lagoon were analysed from a 13-month-long HF radar data set. Surface circulation was related to prevalent wind regimes in the area and to the tidal flow through the lagoon inlet. Three different categories of wind-forcing were defined: bora (NE wind), sirocco (SE wind), and finally the category containing all other wind directions and calms (winds lower than 3 m/sec). Mean flow and vorticity spatial distributions were discussed for different wind conditions. The coastal area about 5 km wide is characterized by a flow field with maximum vorticity. Outside the coastal boundary layer the interior flow is part of the Adriatic basin-wide cyclonic circulation. Two counter-rotating vortices of the dimension of about 4–5 km were evidenced in the average flow field in front of the lagoon inlet (Malamocco inlet) in all situations except for the bora. The vortex-pair is probably associated with the tidal flow through the inlet. The bora wind induces a strong southward coastal jet detached from the coast by about 5 km homogenizing the flow and eliminating the dipole. The average coastal flow pattern in calm wind conditions was also analysed as a function of the strong inflow/outflow (currents in the inlet > 0.7 m s−1) from the lagoon inlet. In both cases the vorticity pattern is similar, with the negative vorticity to the left of the inlet and positive to the right looking seaward.  相似文献   
117.
松辽盆地南部长岭凹陷青一段发育一套优质的半深湖-深湖相暗色页岩,沉积厚度大,分布稳定.页岩层系内存在大量滞留烃,具有可观的页岩油资源潜力.利用大量录井、测井、试油、岩心及分析测试资料,对青一段页岩滞留烃含量及分布、岩相组合、储集空间、矿物组成等富集主控因素进行了全面分析.结果表明,青一段页岩中滞留烃性质以中-轻质油为主,流动性好,在纵向上主要富集在1800~2500 m范围内.青一段页岩可划分为层理型、纹层型、互层型3种岩相类型,其中层理型和纹层型滞留烃含量高,TOC主体大于1.5%,有机质类型以I、II1型为主,热解S1主体大于2×10-3,孔隙度大于5.5%,孔径以介孔-宏孔为主,脆性矿物含量大于50%,可压性好,是主要的页岩油富集模式.通过富集主控因素叠合及有利岩相评价,优选乾安富集区部署实施吉页油1HF井,经压裂测试获得16.4 m3/d的高产页岩油流.采用热解S1法初步估算长岭凹陷青一段页岩油资源量为35×108 t,证实了松辽盆地南部具有可观的页岩油资源潜力.  相似文献   
118.
为探究溶藻弧菌(Vibrio alginolyticus)HY9901血红素结合蛋白HutB作为疫苗候选抗原的可能性,采用PCR方法扩增V.alginolyticus HY9901 hutB基因全长序列,克隆到pMD18-T载体,经双酶切、连接后,定向插入到pET-28a(+)中,构建原核表达载体pET-HutB,转入大肠杆菌BL21(DE3)中进行IPTG诱导表达。SDS-PAGE验证后,优化诱导表达条件和纯化条件,并进行Western-blot分析。结果表明,HutB蛋白在E.coli中诱导表达的最优条件:0.4 mmol/L IPTG,37℃诱导4h,表达的蛋白分子量与预期大小相符,主要以包涵体的形式存在,300 mmol/L咪唑洗脱时效果最佳,能与鼠抗His-tag单抗特异性结合。  相似文献   
119.
泉河是山东省济宁市汶上县一条重要的河流,工业点源、农业面源污染使得泉河污染,水质超标。为净化水质,建设了泉河河道走廊人工湿地工程,总长度23km,规模319.7hm2,总投资5170万元。主要采用河道滞留塘+表面流人工湿地组合工艺,处理汶上县污水处理厂外排水、沿河周边农村生活污水及农田退水,污水处理规模2.0万m3/d。工程2010年10月开工,2011年6月建成并正常运行。通过1a多的运行结果表明,该人工湿地工程具有较高的污染负荷去除率,实现了河道的生态修复和沿河生态环境治理,泉河生态环境得到了明显改善。  相似文献   
120.
A new extracellular κ-carrageenase, namely CgkP, 34.0 kDa in molecular weight, was purified from Pseudoalteromonas sp. QY203. CgkP showed relatively high activity at acidities ranging from pH6.0 to pH9.0 and temperatures ranging from 30℃ to 50℃ with the highest activity at 45℃ and pH7.2. Sodium chloride increased its activity markedly, and KCl increased its activity slightly. The divalent and trivalent metal ions including Cu2+ , Ni2+ , Zn2+ , Mn2+ , Al3+ and Fe3+ significantly inhibited its activity, while Mg2+ did not. CgkP remained 70% of original activity after being incubated at 40℃ for 48 h, and remained 80% of the activity after being incubated at 45℃ for 1 h. It exhibited endo-κ-carrageenase activity, mainly depolymerizing the κ-carrageenan into disaccharide and tetrasaccharide. CgkP was more thermostable than most of previously reported κ-carrageenases with a potential of being used in industry.  相似文献   
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