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41.
Jun Zhao Xin Zhao Lei Chao Wei Zhang Tao You Jie Zhang 《Journal of Zhejiang University. Science. B》2014,15(7):670-680
Pollution discharge disturbs the natural functions of water systems. The environmental microbial community composition and diversity are sensitive key indicators to the impact of water pollutant on the microbial ecology system over time. It is meaningful to develop a way to identify the microbial diversity related to heavy metal effects in evaluating river pollution. Water and sediment samples were collected from eight sections along the Tiaozi River where wastewater and sewage were discharged from Siping City in northeastern China. The main pollutants contents and microbial communities were analyzed. As the primary metal pollutants, zinc (Zn) and arsenic (As) were recorded at the maximum concentrations of 420 and 5.72 μg/L in the water, and 1704 and 1.92 mg/kg in the sediment, respectively. These pollutants posed a threat to the microbial community diversity as only a few species of bacteria and eukaryotes with strong resistance were detected through denaturing gradient gel electrophoresis (DGGE). Acinetobacter johnsonii, Clostridium cellulovorans, and Trichococcus pasteurii were the dominant bacteria in the severely polluted areas. The massive reproduction of Limnodrilus hoffmeisteri almost depleted the dissolved oxygen (DO) and resulted in the decline of the aerobic bacteria. It was noted that the pollution reduced the microbial diversity but the L. hoffmeisteri mass increased as the dominant community, which led to the overconsuming of DO and anaerobic stinking water bodies. Water quality, concentrations of heavy metals, and the spatial distribution of microbial populations have obvious consistencies, which mean that the heavy metals in the river pose a serious stress on the microorganisms. 相似文献
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Improved yield and Zn accumulation for rice grain by Zn fertilization and optimized water management 总被引：1，自引：0，他引：1
Yu-yan WANG Yan-yan WEI Lan-xue DONG Ling-li LU Ying FENG Jie ZHANG Feng-shan PAN Xiao-e YANG 《Journal of Zhejiang University. Science. B》2014,15(4):365-374
研究目的：在生产高度集约化体系下,研究节水灌溉措施及锌肥对水稻产量及锌积累量的影响。创新要点：目前关于干湿交替能否对水稻增产仍存在争议,对锌含量及生物有效性也鲜有报道。因此,针对这些问题,本文系统地研究影响水稻产量及品质的两大限制性因素,即锌肥和灌溉方式对稻米锌生物有效性的影响。研究方法：采用盆钵试验模拟大田锌肥及水分管理方式,两种基因型、两种锌肥种类、两种水分管理,三个重复控制误差。利用电感耦合等离子体质谱（ICP-MS）测定微量元素锌含量,以精米中植酸含量表征锌生物有效性。重要结论：干湿交替在增加了稻米产量、锌含量及积累量方面效果显著。干湿交替结合土施硫酸锌肥可以作为水稻生产体系中获得高产、高锌、高生物有效性的农艺措施。 相似文献
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以十六烷基三甲基溴化铵（CTAB）为有机模板,加入到丙三醇和水的混合溶液中制备碳酸钙并在其母液中进一步合成羟基锡酸锌包覆碳酸钙.通过XRD,SEM,TG-DSC分别对产物的晶型、形貌、热解行为进行了分析,并研究了CTAB浓度对碳酸钙的形貌和晶体结构的影响.结果表明：碳酸钙为枝状文石型碳酸钙,羟基锡酸锌较好的包覆在枝状碳酸钙表面,当CTAB质量浓度为2.2 g/L时,枝状晶体形态最好. 相似文献
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目的：探讨茯砖茶对一次大量饮酒雌鼠肝组织酶的影响。方法：将50只健康昆明种雌性小鼠按体重随机分为白酒模型对照组、空白对照组、茯砖茶组、维生素C＋茯砖茶组、加锌茯砖茶组5个组,白酒模型实验组和空白组在实验期间饮用水;其他各组自由饮用溶于水的茯砖茶、加维生素C的茯砖茶和加乳酸锌的茯砖茶,连续饮用30 d,第30 d行空腹白酒灌胃,16 h后取小鼠肝脏组织制备匀浆,测定其超氧化物歧化酶（superoxide dismutase,SOD）、谷胱甘肽过氧化物酶（glutathione peroxidase,GSH－PX）的含量和谷丙转氨酶（ac－tivity and c transaminase,ALT）、谷草转氨酶（ aspertate aminotransferase,AST）含量。结果：模型组雌鼠的肝组织 SOD 含量低于茯砖茶组（t ＝12．15, P ＜0．01）,茯砖茶＋维生素C组、茯砖茶加锌组SOD含量高于白酒模型组（ P ＜0．01）,茯砖茶＋维生素 C组的SOD含量高于茯砖茶组（ t ＝5．37, P ＜0．05）;白酒模型组GSH－PX含量低于空白组（ t ＝10．47, P ＜0．01）,茯砖茶组的 GSH－PX含量高于白酒模型组（ t ＝7．61, P ＜0．01）;茯砖茶＋维生素C组、加锌茯砖茶组GSH－PX含量高于白酒模型组（ t ＝10．47, P ＜0．01）,添加维生素C和锌后的茯砖茶组的GSH－PX含量高于茯砖茶组（ t ＝11．08, P ＜0．01）;白酒模型组肝组织中 ALT 含量高于空白对照组（ t ＝2．79, P ＜0．01）,也高于茯砖茶＋维生素C组（ t ＝4．26, P ＜0．01）;茯砖茶组、茯砖茶＋维生素C组 AST含量高于模型组（ t ＝2．42, P ＜0．05;t ＝2．26, P ＜0．05）。结论：雌鼠一次大量饮酒会引起SOD和GSH－PX含量下降、ALT及AST含量升高;饮用茯砖茶对于一次大量饮酒后SOD和GSH－PX以及AST有一定保护作用,但对于ALT没有明显的作用;饮用添加了维生素 C的茯砖茶对于肝脏这四种酶的保护作用可能更好。 相似文献
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Sedum alfredii Hance has been identified as zinc (Zn) and cadmium (Cd) co-hyperaccumulator. In this paper the relationships of Zn or Cd hyperaccumulation to the generation and the role of H2O2 in Sedum alfredii H. were examined, The results show that Zn and Cd contents in the shoots of Sedum alfredii H. treated with 1000 μmol/L Zn2 and/or 200 μmol/L Cd2 increased linearly within 15 d. Contents of total S, glutathione (GSH) and H2O2 in shoots also increased within 15 d, and then decreased. Total S and GSH contents in shoots were higher under Cd2 treatment than under Zn2 treatment. However, reverse trends of H2O2 content in shoots were obtained, in which much higher H2O2 content was observed in Zn2 -treated shoots than in Cd2 -treated shoots. Similarly, the microscopic imaging of H2O2 accumulation in leaves using H2O2 probe technique showed that much higher H2O2 accumulation was observed in the Zn2 -treated leaf than in the Cd2 -treated one. These results suggest that there are different responses in the generation of H2O2 upon exposure to Zn2 and Cd2 for the hyperaccumulator Sedum alfredii H. And this is the first report that the generation of H2O2 may play an important role in Zn hyperaccumulation in the leaves. Oar results also imply that GSH may play an important role in the detoxification of dissociated Zn/Cd and the generation of H2O2. 相似文献
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Zn-Br电池作为新一代高能电池在电动汽车、蓄能电站等领域具有广泛的应用前景,目前在国外已经进入了试用阶段。本文从自放电、腐蚀及枝状生长三方面对国外有关Zn—Br电池的应用基础研究作了全面综述,并介绍了有关研究的发展方向。 相似文献
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主要借助扫描电子显微镜,结合物理化学、电化学的基础理论知识,对机械镀锌吸附过程中先导金属的作用机理进行了研究.结果表明机械镀锌吸附过程中先导金属的确起着非常重要的作用,而且先导金属可以促进机械镀锌镀层的结合强度. 相似文献
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本实验采用原子吸收分光光度法对凤阳地区 6类植物性食品中锌的含量进行了分析测定。结果表明 ,凤阳地区谷类含锌量平均为 5 .0 2 1 3mg/kg ;豆类平均为 2 3.0 82 2mg/kg ;咸菜类为 1 6.5 4 65mg/kg ;根茎类为 2 1 .331 6mg/kg ;瓜茄类为 2 4 .470 3mg/kg ;叶嫩茎类为 35 .5 80 8mg/kg。这为本地区调配平衡膳食提供了参考。 相似文献
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本文提出一种能有效地防止在Zn—Br电池中海绵状Zn层出现和枝晶生长的组合添加剂,以及提出一种能有效地抑制非循环Zn—Br电池自放电的高分子化合物的组合添加剂,并讨论了有关问题。 相似文献