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111.
移动危险源根据运输方式不同分为道路移动危险源和水路移动危险源.道路移动危险源主要是危险化学品运输车辆等,水路移动危险源是指危险化学品运输船舶.本文基于物联网技术对移动危险源的监测进行了研究,提出了建立基于无线通信网络的监测系统和建立基于二维码的监测系统,前者对道路与水路移动危险源均适用,后者仅适用于道路移动危险源.理论分析表明利用物联网进行移动危险源的监测是可行的.  相似文献   
112.
Different concentrations of BTEX, including benzene, toluene, ethylbenzene, and three xylene isomers, were added into soil samples to investigate the anaerobic degradation potential by the augmented BTEX-adapted consortia under niwate reducing conditiom. All the BTEX substrates could be anaerobically biodegraded to non-detectable levels within 70 d when the initial concentrations were below 100 mg/kg in soil. Toluene was degraded faster than any other BTEX compounds, and the high-to-low order ofdegradation rates were toluene>ethylbenzene>m. xylene>o-xylene>benzene>P. xylene. Nitrite was accumulated with nitrate reduction. but the accumulation of nitrite had no inhibitory effect on the degradation of BTEX throughout the whole incubation. Indigenous bacteria in tIle soil could enhance the BTEX biodegradation ability of the enriched mixed bacteria. When the six BTEX compounds were simultaneously present in soil, there was no apparent inhibitory effect on their degradation with lower initial concentrations. Alternatively, benzene, o-xylene, and P-xylene degradation were inhibited with higher initial concentrations of 300 mg/kg. Higher BTEX biodegradation rates were observed in soil samples with the addition of sodium acetate compared to the presence of a single BTEX substrate. and the hypothesis of primary-substrate stimulation or cometabolic enhancement of BTEX biodegradation seems likely.  相似文献   
113.
Cu~(2+)、Zn~(2+)对黑褐新糠虾(Neomysis awatschensis)的毒性作用   总被引:1,自引:0,他引:1  
通过在基础海水中添加Cu2 、Zn2 ,研究其对黑褐新糠虾(Neomysis awatschensis)的急、慢性毒性影响.包括了Cu2 、Zn2 对黑褐新糠虾在24、48、72和96 h的半致死浓度(LC50),安全浓度(SC)和在生长、成活、繁殖等方面的影响.结果表明:(1)水体中Cu2 对黑褐新糠虾24、48、72和96 h LC50和SC分别是2843、2363、1432、449 μg/L和4.49 μg/L.Zn2 对黑褐新糠虾24、48、72和96 h LC50和SC分别是10588、2331、1459、664 μg/L和6.64 μg/L.Cu2 对黑褐新糠虾的毒性大,黑褐新糠虾对Cu2 比对Zn2 更为敏感.(2)当5 μg/L≤Cu2 ≤80 μg/L、10 μg/L≤Zn2 ≤160 μg/L时,黑褐新糠虾在处于各浓度的Cu2 、Zn2 试液中经过60d的饲养,均显示一定程度的毒性作用,其成活率、体长和体长增长率随Cu2 、Zn2 浓度的不断增加都有不同程度的降低,与对照组相比均差异显著(P﹤0.05).  相似文献   
114.
云南个旧锡铜多金属矿集区为中国最重要的锡、铜多金属矿集区之一,经过同位素统计分析得出:硫的来源以生物地层沉积硫和海水硫酸盐为主,并可能混入了岩浆硫源;铅的来源复杂,并含有过量的放射性成因铅,明显有上地幔物质参与,且经过了均匀混合,组成稳定;碳来源由海相碳酸盐衍生而来,并主要与碳酸盐溶解作用有关,且可能有部分直接来源于深源碳;氧来源于浅部地壳经部分熔融形成.  相似文献   
115.
东莞市农业土壤重金属的空间分布特征及来源解析   总被引:38,自引:13,他引:25  
对东莞市农业土壤进行了系统采样分析,测定了表层土壤中Cu、Zn、Ni、Cr、Pb、Cd、As和Hg的含量.利用GIS技术和多元地统计结合的方法,研究了上述8种重金属元素的空间分布特征和来源.结果表明,Cu、Zn、Ni、Pb、Cd和Hg的含量均超过广东省土壤背景值,尤其是Hg、Cd和Pb含量分别达到0.24、 0.12和65.38 mg/kg,远高于背景值,说明随着东莞市快速工业化,土壤中重金属呈明显积聚的趋势.上述8种元素可以由3个主因子反映.因子1为“自然源因子”,主要包括元素Cu、Zn、Ni、Cr和As,其高值区主要分布在研究区西部,主要受河流冲积物海相沉积物控制,低值区的空间分布受酸性火山喷出岩风化物和花岗岩风化物影响,因子1的空间分布主要受成土母质控制.因子2为“工业及交通源因子”,主要包括元素Pb和Hg,高值区主要分布在中部过渡区和西部平原区,高值区中心集中在中部过渡区的虎门镇和西部平原区的茶山镇,主要由该区工业污染所致.因子3为“工农业活动因子”,主要包括Cd元素,其空间变异完全受人为随机因素控制.  相似文献   
116.
An experiments were carried out with treatments differing in nitrogen supply (0, 5 and 15 g N/m2) and CO2 levels (350 and 700 μmol/mol) using OTC (open top chamber) equipment to investigate the biomass of Calamagrostis angustifolia and soil active carbon contents after two years. The results showed that elevated CO2 concentration increased the biomass of C. angustifolia and the magnitude of response varied with each growth period. Elevated CO2 concentration has increased aboveground biomass by 16.7% and 17.6% during the jointing and heading periods and only 3.5% and 9.4% during dough and maturity periods. The increases in belowground biomass due to CO2 elevation was 26.5%, 34.0% and 28.7% during the heading, dough and maturity periods, respectively. The responses of biomass to enhanced CO2 concentrations are differed in N levels. Both the increase of aboveground biomass and belowground biomass were greater under high level of N supply (15 g N/m2). Elevated CO2 concentration also increased the allocation of biomass and carbon in root. Under elevated CO2 concentration, the average values of active carbon tended to increase. The increases of soil active soil contents followed the sequence of microbial biomass carbon (10.6%) > dissolved organic carbon (7.5%) > labile oxidable carbon (6.6%) > carbohydrate carbon (4.1%). Stepwise regressions indicated there were significant correlations between the soil active carbon contents and plant biomass. Particularly, microbial biomass carbon, labile oxidable carbon and carbohydrate carbon were found to be correlated with belowground biomass, while dissolved organic carbon has correlation with aboveground biomass. Therefore, increased biomass was regarded as the main driving force for the increase in soil active organic carbon under elevated CO2 concentration.  相似文献   
117.
An experiments were carried out with treatments di ering in nitrogen supply (0, 5 and 15 g N/m2) and CO2 levels (350 and 700 mol/mol) using OTC (open top chamber) equipment to investigate the biomass of Calamagrostis angustifolia and soil active carbon contents after two years. The results showed that elevated CO2 concentration increased the biomass of C. angustifolia and the magnitude of response varied with each growth period. Elevated CO2 concentration has increased aboveground biomass by 16.7% and 17.6% during the jointing and heading periods and only 3.5% and 9.4% during dough and maturity periods. The increases in belowground biomass due to CO2 elevation was 26.5%, 34.0% and 28.7% during the heading, dough and maturity periods, respectively. The responses of biomass to enhanced CO2 concentrations are di ered in N levels. Both the increase of aboveground biomass and belowground biomass were greater under high level of N supply (15 g N/m2). Elevated CO2 concentration also increased the allocation of biomass and carbon in root. Under elevated CO2 concentration, the average values of active carbon tended to increase. The increases of soil active soil contents followed the sequence of microbial biomass carbon (10.6%) > dissolved organic carbon (7.5%) > labile oxidable carbon (6.6%) > carbohydrate carbon (4.1%). Stepwise regressions indicated there were significant correlations between the soil active carbon contents and plant biomass. Particularly, microbial biomass carbon, labile oxidable carbon and carbohydrate carbon were found to be correlated with belowground biomass, while dissolved organic carbon has correlation with aboveground biomass. Therefore, increased biomass was regarded as the main driving force for the increase in soil active organic carbon under elevated CO2 concentration.  相似文献   
118.
北京夏季大气HONO的监测研究   总被引:5,自引:2,他引:3  
在2007-08-14~2007-08-24期间,利用差分光学吸收光谱(DOAS)技术,对北京市大气中HONO、NO2和O3等污染物进行了连续监测,分析了HONO和NO2的日变化特征,讨论了夜间直接排放对HONO来源的贡献,进行了24 h和夜间13 h HONO非均相反应形成与黑碳气溶胶(BC)和相对湿度(RH)等要素的相关分析.结果表明,HONO和NO2均在01:00左右达到峰值,HONO的另一峰值浓度出现在06:00,比NO2第2个峰值出现时间07:00早1 h;夜间(19:00~次日07:00)直接排放对HONO的贡献最大达到31.3%,出现在20:00,平均贡献为15%;夜间HONOcorr/NO2比率与BC和RH具有非常明显的相关性,说明HONO的非均相生成速率与NO2的浓度以及反应介质BC表面的吸附水的浓度即RH成正比,得到夜间HONO平均转化率(HONO/NO2)为0.8%·h-1;而且RH的增加对HONO的非均相形成有利,但是当RH>80%对反应也将产生抑制作用,通过对监测期间的个例分析也证实了这一假设.  相似文献   
119.
盐度对刺参(Apostichopus japonicus)消化酶活力的影响   总被引:1,自引:0,他引:1  
以刺参(Apostichopus japonicus)为实验对象,分别设置5个盐度水平(23、26、29、32和35),采用酶活性分析的方法比较研究了在不同盐度的养殖环境下,刺参消化道内前肠和中肠不同部位蛋白酶、淀粉酶和脂肪酶3种消化酶活性的差异.结果表明,盐度对刺参消化酶活性影响显著(P<0.05).蛋白酶活力在盐度...  相似文献   
120.
山东近海黄海段营养盐结构对初级生产力的影响研究   总被引:1,自引:1,他引:0  
于2006年8月(夏季)、2006年12月(冬季)、2007年4月(春季)、2007年10月(秋季)对山东近海黄海段的初级生产力和营养盐结构进行了调查.结果显示:(1)调查海域初级生产力的年平均值为438 mg/(m(2)·d),并呈现出"春季>夏季>秋季>冬季"的变化趋势;调查海区的营养盐结构表现出明显的季节分化:春...  相似文献   
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