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51.
用紫外光对假单胞菌株进行诱变,以竹炭为载体,将紫外诱变假单胞菌固定在竹炭上,用竹炭固定化紫外诱变假单胞菌处理间甲酚水样。考察竹炭固定化紫外诱变假单胞菌投加量和水样pH值对间甲酚去除的影响以及进水浓度随反应时间的变化关系,研究竹炭固定化紫外诱变假单胞菌去除间甲酚的反应动力学。结果表明:相对于原菌株,菌株经紫外诱变后,生长周期缩短了6h。经紫外照射120s的假单胞菌可以在竹炭表面及内部孔隙形成明显菌胶团,诱变菌在竹炭上所成的生物量明显较未经诱变菌增加。竹炭固定化紫外诱变假单胞菌能有效地去除水样中间甲酚。竹炭固定化紫外诱变假单胞菌投加量和水样pH值影响到间甲酚的去除效果,pH值在4~6时,间甲酚的去除效果较好。20g竹炭固定化紫外诱变假单胞菌处理100mL初始浓度50,100,120,150,180mg·L-1间甲酚模拟水样42h,去除率依次为90.9%,76.4%,72.9%,64.6%和49.7%。竹炭固定化紫外诱变假单胞菌对间甲酚的去除能较好地符合零级反应方程。  相似文献   
52.
This study analyzed the plasma lipid profile, glucose levels and fat deposits in male rats treated with aqueous extract of gross yerba mate, commercial yerba mate or water. Yerba mate treatment did not change body weight gain and lipid profile. The consumption of gross yerba mate significantly increased blood glucose (6.6 mmol/L) as compared to the water (4.8 mmol/L) and commercial group (5.2 mmol/L) and decreased epididymal and intra-abdominal deposits (10.1 mg/g and 23.7 mg/g of weight) as compared to the water (15.4 mg/g and 36.9 mg/g of weight) and commercial group (12.5 mg/g and 28 mg/g of weight). The results suggest that gross yerba mate reduces fat more efficiently but produces a greater increase in blood glucose when compared to commercial yerba mate and water groups.  相似文献   
53.
就碱性过硫酸钾消解紫外分光光度法测定总氮时空白吸光值过高的现象进行了研究,确定蒸馏水和K2S2O8纯度是影响试验结果的关键因素。选用普通蒸馏水双蒸去离子后的高纯水及纯度大于99.0%的进口K2S1O8或国产分析纯K2S2O8二次重结晶配制成的溶液,其余步骤参照国标介绍的方法,即可保证空白吸光值小于0.030。当蒸馏水和K2S2O8纯度不高时,适当改进试验的操作过程,如对所配碱性K2S2O8溶液加微量HCl(1+9)处理、延长消解时间至50min、消解完取出比色管后迅速冷却等方法也可适当降低空白吸光值,但不能确保在0.030以下。消解仪器与分光光度计的不同对分析结果无显著影响。  相似文献   
54.
采用戊二醛法 ,将半抗原磺胺对甲氧嘧啶 (SMD)与载体牛血清白蛋白 (BSA)偶联 ,制得磺胺对甲氧嘧啶全抗原 SMD-BSA。其紫外扫描光谱和红外光谱表明偶联成功。通过改变半抗原 SMD和偶联剂戊二醛的用量 ,制得多种结合比的全抗原 ,这为进一步制备抗 SMD抗体提供了良好的免疫原  相似文献   
55.
对 U V自由基固化和阳离子固化两种机理进行了对照试验 .考察了温度和 O2 对固化速度的影响 ,涂层性能及它们作为 UV固化涂料、油墨的优缺点 ,并从理论上进行了分析 .U V自由基固化和阳离子固化的固化速度随温度的升高而加快 ,并且自由基的固化速度大于阳离子固化速度 .自由基固化体积收缩大 ,附着力差 ;阳离子固化体积收缩小 ,附着力优异 .氧对自由基固化有显著的阻聚作用 ,而对阳离子固化没有阻聚效应 .此外 ,阳离子固化存在“暗反应”,当移走 UV光源后 ,仍会发生固化反应  相似文献   
56.
A long-term (1983–2000) global dataset of Earth’s surface daily-integrated UV exposure was developed from a combination of ISCCP-D1 3 h reflectance measurements (in order to resolve the diurnal variation of cloud conditions) and TOMS total ozone amount. The inversion algorithm developed in our previous study was employed with modifications addressing the conversion of visible reflectance to UV albedo and narrowband UV albedo to broadband albedo over the range of 280–400 nm. Validation of the product was carried out using ground-based measurements at six stations. In general, good agreements between the estimated and measured daily UV exposure are found at most stations; the relative mean and root mean square (RMS) difference varies from 3 to 14% and from 20 to 45%, respectively. Among the stations, San Diego has a fairly low mean difference (9%) and the lowest RMS difference (33%), owing to the prevailing clear sky or uniform cloud cover condition. The RMS difference increases with cloud amount, which is largely caused by mismatch between satellite and ground-based measurements. The effect of diurnal variation in atmospheric opacity associated primarily with cloud on the estimation of daily erythemal UV doses is investigated with both ground-based measurements and ISCCP-D1 data. It is found that daily erythemal UV doses estimated from only a noontime satellite “snapshot” may incur errors larger than 20%, which may be reduced for long-term averaging.  相似文献   
57.
The temporal and spatial variability of the total ozone content (TOC) is examined in respect to the biologically effective ultraviolet radiation on plants. TOC data from 1996 to 2000 over the domain of Central Europe were used. Variability is analysed using correlation and auto-correlation coefficients.The temporal auto-correlation analyses has shown that the only periodicity which could be found was a period of 1 year. The comparison between spatial correlation and the temporal auto-correlation delivers an equivalent value of zero for a distance between 400 and 500 km and at a time lag of 5 days. The influence of temporal and spatial variability of TOC on the biologically effective ultraviolet radiation was quantified by model calculations using action spectra of the DNA-damage and the generalised plant damage (GPD). These were undertaken for a certain location using TOC with various temporal delays or made at other locations with certain distances. The results show that the relative sensitiveness to spatial lags in TOC differs by a factor of three during the year with minimum in August and maximum around December. For temporal lags the sensitiveness changes by a factor of six between August and December.  相似文献   
58.
痢菌净注射液含量测定的新方法   总被引:2,自引:0,他引:2  
唐棣 《四川畜牧兽医》2001,28(7):19-19,21
建立了紫外分光光度法测定痢菌净注射注含量的方法,以甲醇为溶剂,检测波长381nm,在1-20μg/mL范围内吸收度与渡度呈良好的线性关系,r=0.9999,回收率100.0%,RSD为0.16%(n=5),稳定性好,本方法与非水滴定法相比,无需分离,操作简便,快速,结果准确,实验受环境因素影响小,对检验人员身体无危害,并可用复方制剂中痢菌净的含量测定。  相似文献   
59.
A reduction in the number of wounds of pears and apples which developed blue mould (Penicillium expansum) infection was associated with reduced spore concentration. An experimental ultraviolet irradiation treatment of water in a fruit-handling system reduced both spore numbers and fruit rots, but not to a level which would suggest that the technique is worth pursuing to a commercial application stage.  相似文献   
60.
[目的]建立富集板栗种仁中高纯度总酚酸的方法.[方法]以没食子酸为对照品,采用分光光度法测定板栗种仁中总酚酸含量;以总酚酸含量为指标,对提取方法进行系统研究;以总酚酸的得率和精制度为考察指标,研究大孔树脂吸附纯化提取物的工艺条件及参数.[结果]用体积分数为75%的乙醇回流提取的总酚酸获得较高的提取率,通过HPD-826型大孔树脂纯化后,总酚酸得率的质量分数达到83.6%以上,体积分数为70%的乙醇洗脱液总固物中总酚酸的质量分数达到58.1%以上.[结论]采用此种提取及精制方法,可较好地提取纯化板栗种仁中的总酚酸.  相似文献   
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