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161.
氢化物原子荧光光谱法测定铜精矿及铜矿石中砷的研究 总被引:1,自引:0,他引:1
通过对铜精矿及铜矿石中大量铜离子等多种金属离子对原子荧光光谱法测定砷干扰的消除,建立一种适合的溶样方法,选择了最佳的分析条件,克服了普通原子荧光法溶解样品的不足,本方法测定砷的检出限为1μg/g。本方法测定了3个国家一级标准物质中砷的含量,测定值与推荐值吻合,确定方法适合铜含量比较高的样品中砷含量的测定。 相似文献
162.
杀鲑气单胞菌(Aeromonas salmonicida)是引起疖疮病的典型致病细菌,几乎可以侵染所有的鲑科(Aeromonas)鱼类,为水产养殖业带来巨大的经济损失。本研究通过电击转化法将原核表达载体p GFPuv成功导入杀鲑气单胞菌C4菌株(AS-C4)中,获得了绿色荧光蛋白标记的杀鲑气单胞菌菌株AS-C4~(GFP)。AS-C4~(GFP)菌株在氨苄青霉素抗性平板上生长良好,并在紫外光下激发出较强的绿色荧光。通过荧光显微镜观察菌体和PCR检测gfp和杀鲑气单胞菌vap A基因,表明gfp基因已经成功导入AS-C4中。用AS-C4~(GFP)人工感染大西洋鲑(Salmo salar),从死亡鱼的脾脏、肝脏、肾脏中均能分离出AS-C4~(GFP),AS-C4~(GFP)在脾脏中最多。AS-C4~(GFP)具有特异性和可视性,为研究杀鲑气单胞菌对大西洋鲑的侵染途径提供了一种良好的生物材料。 相似文献
163.
正Introduction The amount of the total dissolved salts(TDS)in most of the salt brines on northern Tibet is relatively lower.So the effective brine concentration technique is needed for lithium,boron and potassium extraction from these brine 相似文献
164.
Management of faecal contamination of water would be improved if sources could be accurately identified through water analysis. Human faeces are generally perceived as constituting a greater human health risk than animal faeces, but reliable epidemiological evidence is lacking. United States waterborne disease data suggest that human‐specific enteric viruses account for over half the documented outbreaks. However, in New Zealand, where there is a high grazing animal:human ratio (increasing the relative importance of water‐transmissible zoonoses), it seems prudent to assume that human and animal faecal pollution both constitute a risk to human health. Irrespective of the relative risks, the ability to identify sources would assist in overall management of microbial water quality. Faecal streptococci do not appear to provide reliable faecal source identification. Human and animal sources, respectively, maybe distinguishable by two tests on Bifidobacterium spp.—growth at 45°C in trypticase phytone yeast broth and sorbitol fermentation. Different species of Bacteroides tend to be present in humans and animals, but poor survival in water is a problem. Phages of the Bacteroides fragilis strain HSP40 appear to be human specific, but low counts in effluent in some countries, including New Zealand, may limit their usefulness. Different F‐RNA phage subgroups appear to be associated with human and animal faecal sources. The actinomycete Rhodococcus coprophilus has potential as a grazing animal indicator but it is persistent, and existing culturing techniques are time consuming. The development of DNA‐based techniques, such as polymerase chain reaction (PCR), may assist in the assay of some microbial faecal source indicators. Various faecal sterol isomers offer the possibility of distinguishing between human and animal sources, and even between different animals. Washing powder constituents such as fluorescent whitening agents, sodium tripolyphosphate and linear alkyl benzenes, offer useful human source identifiers. It is unlikely that any single determinand will be useful in all situations, but statistical analysis of appropriate “baskets” of microbial and chemical determinands offers the possibility of identifying and apportioning human and animal faecal inputs to natural waters. 相似文献
165.
FITC‐conjugated lectins proved to be effective probes for differentiating between morphologically similar dinoflagellate species isolated from New Zealand coastal waters. In particular the binding (fluorescence) of peanut (PNA) lectin differentiated G. mikimotoi from Gymnodinium sp. (Waimangu) and G. pulchellum and the non‐binding of Helix pomatia (HPA) and wheat germ (WGA) lectins discriminated between G. mikimotoi and the other Gymnodinium species tested. G. breve (Florida) was differentiated from the New Zealand isolates by binding with soy bean (SBA) lectin. Ulex europeus (UEA) distinguished the toxic species Alexandrium minutum from the morphologically similar, but non‐toxic, Cachonina hallii. Two strains of Prorocentrum lima (Spain and Rangaunu) were not differentiated by the lectins, but P. lima was differentiated from P. compressum. 相似文献
166.
用分离于病(死)牙鲆(Paralichthys olivaceus L.)的一种新病原弧菌——秦皇岛弧菌(Vibrio qinhuangdaora sp.nov.)的代表菌株(HQ010712-1株),分别制备全菌(OK)及热处理(121℃作用1h)的菌体(O)免疫原,强化免疫接种家兔制备相应抗血清,对供试12株秦皇岛弧菌进行了血清型检定,结果表明均存在同种的K抗原和同种的O抗原(血清同源),其中O抗原具有强免疫原性、K抗原的免疫原性弱但具有强O凝集抑制作用;以相应OK抗血清为第一抗体,以标准的羊抗兔IgG荧光抗体为第二抗体,对12株秦皇岛弧菌的纯培养物及用代表菌株(HQ010712-1)人工感染病死牙鲆的肝组织进行了间接荧光抗体染色,结果显示了特异的荧光反应。 相似文献
167.
168.
生活垃圾具有大孔隙特性,垃圾中水分运动常表现出优先流特征。针对垃圾组成复杂、难以切片的特点,设计了一种能方便地得到垃圾染色剖面的试验方法。使用填埋场不同深度处的垃圾样进行染色示踪试验,对染色后的垃圾柱分别进行水平切片和竖向切片。基于数字图像处理技术,研究了垃圾中优先流特征。垃圾中大孔隙多、基质少,染色模式与土中不同,基质部分的染色比例较高。试验所得的染色面积比和染色深度能反映出垃圾中优先流的明显程度,染色面积比与参与优先流的大孔隙比例有关,染色面积比越大,优先流越明显,而染色深度与基质流比例有关,上部垃圾中基质流比例越低,入渗深度越深。不同入渗强度的试验结果表明,入渗强度越大时垃圾中优先流程度越高;不同初始含水率的试验结果表明,初始含水率高的垃圾试样中优先流更明显;不同埋深垃圾试样的试验结果表明,浅层垃圾中更易产生优先流。竖向切片与水平向切片所得规律完全一致,试验方法在实现垃圾染色示踪和切片研究的同时,未改变垃圾中优先流原有规律,准确揭示了垃圾中优先流特征。 相似文献
169.