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101.
胶州湾入海污染物总量控制研究   总被引:8,自引:3,他引:5  
张学庆  孙英兰 《海洋环境科学》2007,26(4):347-350,359
在胶州湾水质数值模拟的基础上,建立了污染物总量控制模型.计算了各个点源的响应系数,分担率及环境容量.结果表明,胶州湾内COD各入海污染源均有余量,不需要削减.胶州湾东北部N、P污染较严重,污染物入海总量已经超过海域的环境容量.研究结果将为胶州湾污水排海、海域水质管理、总量控制规划编制提供科学依据.  相似文献   
102.
张磊  刘哲  张经 《海洋环境科学》2007,26(5):450-454,465
通过构造理想的四水团混合模型,对传统温-盐二指标图解和三指标钜阵求解分析水团混合的方法进行比较,认为三指标估算结果更接近真实值.但温、盐数据因为易得且准确性好,所以传统方法仍具有一定的实用价值.在东海西南海区的应用中,检验了天然放射性226Ra核素作为第三个指标的可行性,并对实际水团混合情况进行了评估.证实黑潮次表层水在夏季顺陆坡边缘爬升后沿底部向岸运移,并在近岸涌升,是东海陆架区营养盐外源补充的一个重要动力.  相似文献   
103.
采用固相萃取-超高效液相色谱串联质谱法测定环境水样中25种磺胺类和喹诺酮类抗生素,通过优化试验条件,使方法在2.00μg/L~200μg/L范围内线性良好,方法检出限为1.01ng/L~2.85ng/L,7次测定结果的RSD为2.3%~8.0%。将该方法用于自来水和地表水测定,结果均为未检出,高、低质量浓度水平的加标回收率为61.2%~102%。  相似文献   
104.
采用固相萃取/高效液相色谱-三重四级杆质谱法同时测定医疗废水中的20种超痕量抗生素残留,通过优化试验条件,使方法在100μg/L~100μg/L范围内线性良好,方法检出限为024ng/L~122ng/L。空白水样和实际水样3个质量浓度水平的加标回收率分别为80.2%~108%和75.8%~114%,6次测定结果的RSD分别为2.4%~8.4%和1.7%~8.1%。将该方法用于测定重庆市2家三甲医院医疗废水中的超痕量抗生素残留,结果有11种抗生素检出,其余均为未检出。  相似文献   
105.
The adsorption behavior of p-aminobenzoic acid and o-aminobenzoic acid onto the different polymeric adsorbents was systematically investigated as a function of the solution concentration and temperature.Experimental results indicated that the equilibrium adsorption data of the four polymeric adsorbents fitted well in the Freundlich isotherm.The adsorption capacity of multi-functional polymeric adsorbent NJ-99 was the highest,which might be attributed to the strong hydrogen-bonding interaction between the amino groups on the resin and the carboxyl group of aminobenzoic acid.The adsorption capacity of o-aminobenzoic acid onto any adsorbent was higher than p-aminobenzoic acid.Thermodynamic studies suggested the exothermic,spontaneous physical adsorption process.Adsorption kinetics results showed that the adsorption followed the pseudo-second-order kinetics model and the intraparticle mass transfer process was the rate-controlling step.  相似文献   
106.
In order to understand the complex transport phenomena in a passive direct methanol fuel cell (DMFC), a theoretical model is essential. The analytical model provides a computationally efficient framework with a clear physical meaning. For this, a non-isothermal, analytical model for the passive DMFC has been developed in this study. The model considers the coupled heat and mass transport along with electrochemical reactions. The model is successfully validated with the experimental data. The model accurately describes the various species transport phenomena including methanol crossover and water crossover, heat transport phenomena, and efficiencies related to the passive DMFC. It suggests that the maximum real efficiency can be achieved by running the cell at low methanol feed concentration and moderate current density. The model also accurately predicts the effect of various operating and geometrical parameters on the cell performance such as methanol feed concentration, surrounding temperature, and polymer electrolyte membrane thickness. The model predictions are in accordance with the findings of the other researchers. The model is rapidly implementable and can be used in real-time simulation and control of the passive DMFC. This comprehensive model can be used for diagnostic purpose as well.  相似文献   
107.
The effect of air mass (AM) on the performance of multi-crystalline silicon (m-Si), amorphous silicon (a-Si), and hetero-junction with intrinsic thin layer (HIT)-technology-based photovoltaic (PV) modules are evaluated for representative day of four seasons during the year 2011 for composite climate of India. To find the best performing PV module technology with respect to AM at the site, annual energy yields and performance ratio against different AM bands (AM 1–4.5) are plotted. It is found that HIT modules perform better than m-Si and a-Si at each AM band. Annual energy yields for all three technologies decrease with increasing order of AM bands. The performance ratio for HIT and m-SI modules initially increases and then decreases with increasing order of AM bands. However, for a-Si modules, the performance ratio decreases with increasing order of the AM bands.  相似文献   
108.
The free living nematode Caenorhabditis elegans is a proven model organism for lipid metabolism research. Total lipids of C. elegans were extracted using chloroform and methanol in 2:1 ratio (v/v). Fatty acids composition of the extracted total lipids was converted to their corresponding fatty acids methyl esters (FAMEs) and analyzed by gas chromatography/accurate mass quadrupole time of flight mass spectrometry using both electron ionization and chemical ionization techniques. Twenty-eight fatty acids consisting of 12 to 22 carbon atoms were identified, 65% of them were unsaturated. Fatty acids containing 12 to17 carbons were mostly saturated with stearic acid (18:0) as the major constituent. Several branched-chain fatty acids were identified. Methyl-14-methylhexadecanoate (iso- 17:0) was the major identified branched fatty acid. This is the first report to detect the intact molecular parent ions of the identified fatty acids in C. elegans using chemical ionization compared to electron ionization which produced fragmentations of the FAMEs.  相似文献   
109.
The popular microblogging service, Twitter, contains a variety of potential orientations—interpersonal, broadcast, news, advertising, public service, political, and so on—in its operation and applications. As an evolving social media platform, specificity and context are essential in understanding its significance and use-value. This paper investigates the multiple modalities of Twitter in the context of formal politics and, in particular, the Greens party in Australia. Presenting original evidence drawn from the Greens Members of Parliament and their advisers, it is shown how Twitter is mobilized in response to particular news agendas and stories, unfolding political events and processes, and an ongoing need for the Greens to speak simultaneously to committed environmentalists and the broader electorate. These uses reveal that Twitter is an important addition to the media ecology mix in the conduct of environmental politics, playing a direct role in political communication, strategies, and actions.  相似文献   
110.
This paper examines ideologies about nature and the environment in popular, animated Hollywood films—including The Lorax, Wall-E, and Ice Age 2—through a symptomatic reading. The primary goal of the analysis is to elucidate key omissions in these texts through an assessment of the problematic—defined in this research as an a-priori answer to perceived audience concerns regarding the role of consumerism and corporate culture in environmental problems. Silences in the films revolve around: how environmental problems are defined; what the consequences are; who the responsible parties are; and what potential solutions exist to mitigate them. The significance of the research is underscored by the formation of an increasingly intimate relationship between children, consumer culture, and commercial media in the USA, as well as the increasingly dire information emerging about global environmental issues. This analysis reveals the dual, often conflicting, messages that commercial film provides for its young audiences about pivotal environmental problems and their potential resolution.  相似文献   
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