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81.
82.
放射性污染物粘膜铺设车是核事故应急的一种主要装备。为解决放射性污染物粘膜铺设车多工位实时操控需要,设计了由主控屏、辅控屏和手持终端三种控制终端共同组成上位机的控制系统。该系统以主控屏作为交互中心,通过标准RS232接口与下位机通信;辅控屏和手持终端作为主控屏外设,分别通过CET-5E网线和蓝牙将数据实时传输至主控屏,实现不同工位下的可靠操控。下位机主控制器以ARM7作为主处理器,采用Modbus通信协议与上位机通信,便于系统后续拓展开发。实验表明,该多终端操控系统不受辐射环境干扰,通信稳定,操作便捷,实时性高,符合粘膜铺设车作业工况要求。这种通过主屏地址映射实现多终端控制的方式,有利于降低主控制器仲裁压力、减少数据冗余、提高系统时效,适合在各种特种车辆的控制系统中推广应用。  相似文献   
83.
The elimination rates of pentachlorophenol, hexachlorobenzene and mirex were estimated in rainbow trout that were held at 4, 12 and 18°C for 120 days following a single oral exposure. The results suggested temperature could become an important environmental variable in deriving a coefficient for the elimination component of a contaminant dynamics model. This response would be most applicable for those substances that are eliminated relatively rapidly, and those models that simulate the contaminant dynamics of fish in its natural environment.  相似文献   
84.
利用人工介质改善太湖水源地水质的研究   总被引:2,自引:0,他引:2  
采用组合介质、弹性介质、无纺布介质等3种人工介质进行了改善太湖水源地水质的中试研究.结果表明,组合介质上的生物量及生物活性分别为(26.99±9.4)μgP/g和(127.13±79.4)μgTF/(g·h),均高于无纺布介质和弹性介质的,且其净化效果更佳,是较为适用的人工介质.组合介质通过富集微生物来净化水质,对微量有机物的去除效果明显.当HRT为7d、组合介质的填充率为26.8%时,对TOC、CODMn、Chl-a、藻毒素的平均去除率分别为42.1%、22.5%、71.9%、67.9%.  相似文献   
85.
S. BRAGG  BSc  DIC  MSc  C. J. SOLLARS  BSc  DIC  MSc  PhD    R. PERRY  BSc  PhD  CChem  FRSC  FRSH 《Water and Environment Journal》1990,4(2):203-211
Over 100000 renal failure patients are treated by dialysis in the European Community (EC), and the number is rapidly increasing due to better medical care. The full importance of the quality of water used for renal dialysis is only now being recognized. Aluminium intoxication, first described in the early 1970s, highlighted the need for adequate treatment of water used to prepare dialysate. Other materials harmful to dialysis patients, such as chloramines, may arise as a result of water treatment practice. The paper presents a European-wide assessment of the problems of trace contaminants in dialysis feed water, and examines some contaminant sources in mains water in the light of dialysis water standards and the current treatment techniques available.  相似文献   
86.
陈彩霞  栾和林 《矿冶》2016,25(2):67-70
选冶药剂中存在多种高关注度物(SVHC),它们是具有致癌、致畸及生殖毒性的物质(CMR),具有持久性、生物累积性、毒性物质(PBT),具有高持久、生物累积性物质(v Pv B)。此外选冶药剂中还有定义为新型污染物、POPs、内分泌污染物、冶炼中的二恶英全合成的前体物及大量的致癌及可能致癌的有毒有害物。但人们对其缺乏认知及法规监管。与SVHC、PBT等单一污染不同的是选冶药剂有毒有害物质污染与全球最大最持久的重金属污染的交叉、叠加与复合。  相似文献   
87.
在对高锰酸钾复合药剂预处理工艺去除水中色度效果的研究中发现:高锰酸钾复合药剂预处理工艺对水中色度的去除效果十分理想,对水中色度的浊度和去除效果要远远好于单独投加聚合氯化铝,聚合硫酸铁和氯化铁工艺对色度和浊度的去除效果。  相似文献   
88.
Recent studies have added substantially to our knowledge of spatial and temporal trends of persistent organic pollutants and heavy metals in the Canadian Arctic marine ecosystem. This paper reviews the current state of knowledge of contaminants in marine biota in the Canadian Arctic and where possible, discusses biological effects. The geographic coverage of information on contaminants such as persistent organochlorines (OCs) (PCBs, DDT- and chlordane-related compounds, hexachlorocyclohexanes, toxaphene) and heavy metals (mercury, selenium, cadmium, lead) in tissues of marine mammal and sea birds is relatively complete. All major beluga, ringed seal and polar bear stocks along with several major sea bird colonies have been sampled and analysed for OC and heavy metal contaminants. Studies on contaminants in walrus are limited to Foxe Basin and northern Québec stocks, while migratory harp seals have only been studied recently at one location. Contaminant measurements in bearded seal, harbour seal, bowhead whale and killer whale tissues from the Canadian Arctic are very limited or non-existent. Many of the temporal trend data for contaminants in Canadian Arctic biota are confounded by changes in analytical methodology, as well as by variability due to age/size, or to dietary and population shifts. Despite this, studies of OCs in ringed seal blubber at Holman Island and in sea birds at Prince Leopold Island in Lancaster Sound show declining concentrations of PCBs and DDT-related compounds from the 1970s to 1980s then a levelling off during the 1980s and early 1990s. For other OCs, such as chlordane, HCH and toxaphene, limited data for the 1980s to early 1990s suggests few significant declines in concentrations in marine mammals or sea birds. Temporal trend studies of heavy metals in ringed seals and beluga found higher mean concentrations of mercury in more recent (1993/1994) samples than in earlier collections (1981–1984 in eastern Arctic, 1972–1973 in western Arctic) for both species. Rates of accumulation of mercury are also higher in present day animals than 10–20 years ago. Cadmium concentrations in the same animals (eastern Arctic only) showed no change over a 10-year period. No temporal trend data are available for metals in sea birds or polar bears. There have been major advances in knowledge of specific biomarkers in Canadian Arctic biota over the past few years. The species with the most significant risk of exposure to PCBs and OC pesticides may be the polar bear which, based on comparison with EROD activity in other marine mammals (beluga, ringed seal), appears to have elevated CYP1A-mediated activity. The MFO enzyme data for polar bear, beluga and seals suggest that even the relatively low levels of contaminants present in Arctic animals may not be without biological effects, especially during years of poor feeding.  相似文献   
89.
建立基于连续投影算法(successive projections algorithm,SPA)-多元线性回归(multiple linear regression,MLR)-受试者特性(receiver operating characteristic,ROC)分析鸡胴体表面稀释污染物识别方法。首先采用高光谱成像系统获取了20个涂有稀释污染物的鸡胴体图像,再利用SPA从1 232个波长中提取出10个特征波长,然后通过MLR方法构建识别函数和特征波长光谱值之间的回归模型,最后通过ROC分析方法,确定出能够获得高真阳性率(true positive rate,TPR)和低假阳性率(false positive rate,FPR)的最佳分类阈值,并据此对鸡胴体表面稀释后的污染物进行检测。结果显示,利用SPA-MLR-ROC分类器检测20个污染鸡胴体样本,检出污染区域的TPR达到98.08%,FPR仅为0.39%,高于波段比算法以及双波段算法检测相同样本的准确率,可见,SPA-MLRROC分类器方法检测鸡胴体表面稀释污染物获得了较好的效果,但由于样本数量有限,还需要具有较大样本量的研究来进一步验证此方法检测结果的稳定性。  相似文献   
90.
Natural dibenzo-α-pyrones (DAPs) can be viewed from two opposite angles. From one angle, the gastrointestinal metabolites urolithins are regarded as beneficial, while from the other, the emerging mycotoxin alternariol and related fungal metabolites are evaluated critically with regards to potential hazardous effects. Thus, the important question is: can the structural characteristics of DAP subgroups be held responsible for distinct bioactivity patterns? If not, certain toxicological and/or pharmacological aspects of natural DAPs might yet await elucidation. Thus, this review focuses on comparing published data on the two groups of natural DAPs regarding both adverse and beneficial effects on human health. Literature on genotoxic, estrogenic, endocrine-disruptive effects, as well as on the induction of the cellular anti-oxidative defense system, anti-inflammatory properties, the inhibition of kinases, the activation of mitophagy and the induction of autophagy, is gathered and critically reviewed. Indeed, comparing published data suggests similar bioactivity profiles of alternariol and urolithin A. Thus, the current stratification into hazardous Alternaria toxins and healthy urolithins seems debatable. An extrapolation of bioactivities to the other DAP sub-class could serve as a promising base for further research. Conclusively, urolithins should be further evaluated toward high-dose toxicity, while alternariol derivatives could be promising chemicals for the development of therapeutics.  相似文献   
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