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1.
使用程序的模块化结构,连接复盖技术成功地解决了BASIC可利用空间少的限制,比DBASEⅢ语言编制的系统速度快、效率高,不仅可以完成数据的搜集和处理还可完成数据的归集和存档.友好的用户界面为用户提供了一个良好的使用环境.  相似文献   

2.
通过介绍克拉玛依市六、九区含油废水的来源、处理现状等情况,从生态、社会和经济效益角度出发,分析了不同用途的水资源化利用的可行性,并进行了经济可行性分析,得到含油废水用于绿化和生态建设的最佳可行方案。  相似文献   

3.
通过分析我国相关场地污染现状和需求,设计了场地污染监测预警与决策一体化系统,利用物联网设备实时监测采集污染数据,并通过数据传输技术SignalR进行数据传输,再使用三维地理框架Cesium反映监测区域的污染情况,保证对污染处理响应的实时性和高效性,指出三维虚拟地理技术与大数据、物联网技术结合是系统的发展方向。  相似文献   

4.
GPRS烟气在线监控系统的设计   总被引:7,自引:1,他引:6  
阐述了采用完全抽取方式的GPRS烟气在线监控系统的功能和构成。该系统从功能上分为烟气信息监测监控收集子系统、烟气信息加工及处理子系统和环境管理决策支持及信息发布子系统,结构上分为监测点和监控中心两部分。监控中心包括省级监控中心和市级监控中心,监测点包括仪器分析单元、控制单元和通讯系统。指出基于中国移动GPRS/GSM的烟气数据监控系统具有建设使用成本低、监测监控范围大、积木化结构、技术先进和数据并行收取等特点,具有广阔的应用前景。  相似文献   

5.
文章从介绍氯化聚乙烯生产工艺入手,分析了项目实施前后水平衡,对项目实施前后新鲜水,中水使用及废水排放量进行了比较,对项目实施的技术、经济可行性进行了论证,阐述了项目实施一年来取得的经济、环境和社会效益,揭示了本项目实施对同行业和周围企业的示范引导作用。  相似文献   

6.
针对太湖蓝藻遥感监测自动化、智能化等业务需求,研究了太湖蓝藻遥感自动解译系统的总体架构、功能模块等。系统包括遥感数据接收子系统、蓝藻遥感解译子系统和海量遥感数据管理子系统,可实现从数据接收到报告编制全流程自动化处理。  相似文献   

7.
使用无锡市环境监测中心站环境遥感综合处理系统,对2017年7—11月FY-3/MERSI影像数据进行蓝藻水华提取分析,并通过当日与国外MODIS、VIIRS影像数据的蓝藻水华提取结果进行协同比对,验证FY-3/MERSI影像在蓝藻水华预警监测业务化应用的前景。结果表明,3种数据源均能实现蓝藻水华空间分布的业务化运行;由于卫星过境时间的不同,可综合利用这3种数据源观测太湖蓝藻水华在一天中的动态变化,分析蓝藻水华的发生规律。  相似文献   

8.
阐述了上海市环境空气自动监控数据采集系统的发展历程,介绍了系统的应用功能,分析了其在管理方式、运行维护、应用扩展等环节存在的问题。建议制定数据采集系统的维护管理与考核制度,统一数据来源与数据使用规则;推广电子化管理,加强突发异常情况的维护;增加仪器状态参数的报警功能及站房环境与门禁系统的监控,丰富现场点检内容,建立可视化运维平台,保障系统平稳运行。  相似文献   

9.
电极是完成阳极溶出伏安法分析测试的关键。本文就其电极的选择、处理、使用、维护等作了较详细的说明,以保证获得准确的测定数据  相似文献   

10.
由一个环境执法事件所引发的对数据有效性争议,对目前环境监测中实际存在的部分问题如监测数据修约、环保设施处理效率的评价、大气污染源监测等进行了探讨,对今后提高监测系统的数据质量具有很好的指导作用.  相似文献   

11.
Requirements for static (prediction of L(den) and diurnal averaged noise pattern) and dynamic (prediction of 15 min and 60 min evolution of L(Aeq) and statistical levels L(A90,)L(A50) and L(A10)) noise level monitoring are investigated in this paper. Noise levels are measured for 72 consecutive days at 5 neighboring streets in an inner-city noise measurement network in Gent, Flanders, Belgium. We present a method to make predictions based on a fixed monitoring station, combined with short-term sampling at temporary stations. It is shown that relying on a fixed station improves the estimation of L(den) at other locations, and allows for the reduction of the number of samples needed and their duration; L(den) is estimated with an error that does not exceed 1.5 dB(A) to 3.4 dB(A) according to the location, for 90% of the 3 × 15 min samples. Also the diurnal averaged noise pattern can be estimated with a good accuracy in this way. It was shown that there is an optimal location for the fixed station which can be found by short-term measurements only. Short-term level predictions were shown to be more difficult; 7 day samples were needed to build models able to estimate the evolution of L(Aeq,60min) with a RMSE ranging between 1.4 dB(A) and 3.7 dB(A). These higher values can be explained by the very pronounced short-term variations appearing in typical streets, which are not correlated between locations. On the other hand, moderately accurate predictions can be achieved, even based on short-term sampling (a 3 × 15 minute sampling duration seems to be sufficient for many of the accuracy goals set related to static and dynamic monitoring). Finally, the method proposed also allows for the prediction of the evolution of statistical indicators.  相似文献   

12.
A number of methods are used to assess exposure to high-molecular weight allergens. In the occupational setting, airborne dust is often collected on filters using pumps, the filters are eluted and allergen content in the eluate analysed using immunoassays. Collecting inhalable dust using person-carried pumps may be considered the gold standard. Other allergen sampling methods are available. Recently, a method that collects nasally inhaled dust on adhesive surfaces within nasal samplers has been developed. Allergen content can be analysed in eluates using sensitive enzyme immunoassays, or allergen-bearing particles can be immunostained using antibodies, and studied under the microscope. Settling airborne dust can be collected in petri dishes, a cheap and simple method that has been utilised in large-scale exposure studies. Collection of reservoir dust from surfaces using vacuum cleaners with a dust collector is commonly used to measure pet or mite allergens in homes. The sampling methods differ in properties and relevance to personal allergen exposure. Since methods for all steps from sampling to analysis differ between laboratories, determining occupational exposure limits for protein allergens is today unfeasible. A general standardisation of methods is needed.  相似文献   

13.
Passive samplers provide an excellent opportunity to perform indicative measurements or establish a dense network of measuring sites. A drawback compared with conventional active measuring methods is the larger spread of results. This variation can, to a large extent, be attributed to the influence of temperature, sampler geometry and wind on sampling results. A proper design of sampler geometry and optimum choice of draught shield can reduce the influence of wind velocity on a badge type sampler to less than 10%. Wire mesh screens prove to be inadequate in damping turbulence. Filters give good results. Attention should be paid to the size and isolation value of the walls of the sampler to prevent thermal updrafts occurring within the sampler. Tube type samplers are less influenced by wind, provided that turbulence is prevented from influencing diffusion within the sampler.  相似文献   

14.
The extensive use of the broad range of pesticides employed to maintain golf courses has prompted serious environmental concerns in Japan since courses tend to be located in mountainous regions, often in close proximity to virgin water sources. Since older empirical methods are not appropriate for substance identification and determination of substance concentrations on the ppb order, gas chromatographyquadrupole mass spectrometry (GC/QPMS) can be employed. A simple extraction of 500 ml of drainage pond water gives a sample which allows identification of pesticides with quantitation on the ppb order using selected ion monitoring (SIM). A sample of drainage pond water from a golf course revealed fenitrothion, funitrothion, chlorothalonil and isoprothiolane in concentrations of 120.1, 20.7, 45.6 and 130.5 ppb, respectively.  相似文献   

15.
Dust monitoring using sticky pads was popularised in the 1980s. The discolouration caused by dust adhering to white adhesive material was measured with a smoke stain reflectometer. This loss of reflectance was expressed as the percentage effective area coverage (EAC%) per day. EAC% can be used as a measure of nuisance caused by dust. EAC% may also be measured with a hand-held Sticky Pad Reader (SPR). Sticky pads can be mounted on flat or cylindrical surfaces to measure dust by deposition or in flux. An alternative method was developed in the 1990s that measured total dust coverage using computer-based scanning. DustScan used a transparent adhesive film wrapped around a vertical cylinder with magnetic north marked. The sticky pad was sealed with another transparent sheet before scanning at 50 dots per inch (dpi). Dust levels were assessed by comparing the grey-scale values of pixels in the exposed area with an unexposed reference area. Insects and other extraneous material could be ‘masked out’ from the computer analysis. Dust coverage was expressed as percentage absolute area coverage (AAC%). DustScan has subsequently been developed commercially. A limited trial indicated that monitoring periods of 7–14 days were preferred to avoid dust saturation of the sticky pad. A method for calculating EAC% has been developed and shown to have a high degree of correspondence with an SPR. A trial for the Minerals Industry Research Organisation (MIRO) made comparisons between DustScan and other dust monitoring methods. Dust nuisance limits based on AAC% and EAC% are proposed.par  相似文献   

16.
使用全自动固相萃取仪、C18膜-毛细管气相色谱-电子捕获检测器的分析方法检测水中具有致癌性的卤代醚,回收率范围71.8%~126%,检出限0.5~1.5μg/L,与EPA611相比,更加快速、准确,能够满足我国饮用水和废水的分析要求。  相似文献   

17.
In the northern hemisphere moose has been found to be suitable as a monitoring animal for the presence of cadmium in the environment. The metal accumulates mainly in the kidney and the liver, with the rate of accumulation dependent on age and possibly also on gender. Collection of tissue material often results in sample selections with disparate age and gender composition, which makes comparison between different regions and different studies difficult. A previous large scale investigation of metals in kidney and liver from moose in Sweden provided Cd data (n = 3,817 and 3,802, respectively) to further explore the relation between Cd accumulation and age/gender. Based on local averages, the individual deviations were analysed with respect to the factors age and gender resulting in an 'ageing function' for each gender and organ. In addition, estimates of the pure individual variations were obtained; the standard deviations correspond to a factor 1.7-1.9 for the Cd concentration, which indicates that 25-30 samples are needed to give a representative mean value (with RSD approximately 10%). In order to be able to compare results from different studies, all individual results can be transformed to represent a 'standard moose' with respect to age and gender. A comparison along these lines was undertaken between Cd levels in Alaska and Sweden. Finally, a relationship between the Cd levels in kidney and liver was derived, providing at least rough estimates for kidney from liver values (or vice versa).  相似文献   

18.
Aquatic total phosphorus (Tot-P) is measured 30 m distant from rainbow trout (Oncorhynchus mykiss) cages, for regulatory compliance on the Canadian side of Lake Huron. The ability to predict changes in near-field Tot-P concentrations from changes in production, or to explain near-field concentrations in the event of compromised reference sites, would be very useful for managers and farmers. A logical first step in the development of a near-field model is the estimation of down-current Tot-P concentrations. A nutritional mass balance approach was used to calculate the amount of non-settleable Tot-P which was divided by the corresponding flushing volume over four separate production periods. Despite a number of uncertainties, such as cage effects on flushing volume, the contribution of particulate phosphorus, fish distribution, feed conversion ratio, and ingestion-excretion time; accuracy (slope = 1.06) and precision (r(2) = 0.75) of modelled estimates fit well with empirical results. It was concluded that 30 m down-current Tot-P concentrations could be modelled under a diverse set of culture and environmental conditions, suggesting typical 'near-field' concentrations of Tot-P can be explained on the basis of farm activities.  相似文献   

19.
A liquid chromatographic method for the determination of aldehydes and ketones based on mass spectrometric detection is described. Recently developed modular derivatizing agents are employed for analysis. These hydrazine reagents, e.g. 4-dimethylamino-6-(4-methoxy-1-naphthyl)-1,3,5-triazine-2-hydrazine (DMNTH), react with the carbonyl compounds with the formation of the respective hydrazones, which are separated by HPLC-MS with atmospheric pressure chemical ionization in the positive mode. Electrospray ionization may also be used for analysis. Particular focus is directed on various calibration approaches, including external calibration with standard solutions and internal calibration with a hydrazone standard of cyclobutanone, an aldehyde not likely to occur in real samples. A second approach for internal calibration is based on the 13C2-labelled acetaldehyde hydrazone standard. Different calibration approaches may then be used for the analysis of real samples. Limits of detection range from 2 x 10(-8) to 5 x 10(-8) mol L-1 for a series of hydrazones, including hydrazones of saturated aldehydes with alkyl chain lengths from 1 to 7 carbon atoms, and hydrazones of selected unsaturated and aromatic aldehydes as well as ketone hydrazones.  相似文献   

20.
The measurement in some living organisms of adequate biomarkers (e.g. cytochrome P-450) to assess the organic pollution in freshwater ecosystems is well established. However, the sensitivity of this approach depends on the analytical measurement method employed and on the chosen living organism for the biomonitoring. Three analytical methods were compared for measuring cytochrome P-450 1A levels in wild brown trout (Salmo trutta): a catalytic one, based on measurement of the ethoxyresorufin-O-deethylase (EROD) activity, and two immunochemical methods, namely, enzyme-linked immunosorbent assay (ELISA) and western blotting. The P-450 1A levels in those animals from a river located in an industrialized area (Trubia River, Northern Spain) and also from individuals living in a low-contamination reference area have been studied. Significant differences (Mann-Whitney U-test, P < 0.01) between rivers were found (ELISA and EROD assays), with the values for Trubia river being similar to those observed in laboratory experiments with well known P-450 1A inducers. However, no significant differences were observed in terms of sex and age. Western blot analysis confirmed the presence of a single band of 56 kDa (corresponding with P-450 1 A protein) in microsomes of fish caught in the Trubia river. On the other hand, and associated with the chemical analysis of PAHs in the waters of both rivers by SPME-GC-MS, high levels of naphthalene (P-450 1A inducer) in the contaminated river were found. In brief, a wide difference between basal levels and P-450 1A induction levels could be detected in trout living in natural field conditions using both EROD activity assay and immunochemical methods. Therefore, brown trout could constitute a good sentinel organism to biomonitor the exposure to PAHs in rivers using P-450 1A measurements.  相似文献   

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