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91.
In this study, a dynamic interval-parameter optimization model (DIP-REM) has been developed for supporting long-term energy systems planning in association with GHG mitigation in the region of Liaoning province. The model can describe Liaoning province energy planning systems as networks of a series of energy flows, transferring extracted/imported energy resources to end users through a variety of conversion and transmission technologies over a number of periods and address the problem of GHG-emission reduction within a general energy planning systems framework under uncertainty. Two scenarios (including a reference case) are considered corresponding to different GHG-emission mitigation levels for in-depth analysis of interactions existing among energy, socio-economy and environment in the Liaoning province. Useful solutions for Liaoning province energy planning systems have been generated, reflecting trade-offs among energy-related, environmental and economic considerations. The results can not only provide optimal energy resource/service allocation and capacity-expansion plans, but also help decision-makers identify desired policies for GHG mitigation with a cost-effective manner in the region of Liaoning province. Thus, it can be used by decision makers as an effective technique in examining and visualizing impacts of energy and environmental policies, regional development strategies and emission reduction measures within an integrated and dynamic framework. 相似文献
92.
《Environmental Modelling & Software》2000,15(6-7):681-692
High resolution models of air pollution transport and transformation are necessary in order to test possible abatement strategies based on pollution control and to forecast high pollution episodes. Models are especially relevant for secondary pollutants like ozone and nitrogen dioxide which are formed in the atmosphere through nonlinear chemical reactions involving primary pollutant species far from their sources. Often we are trying to resolve the interactions between plumes from point sources such as power stations and regional pollution tides of ozone formed in other European countries. One method of tackling this problem of different scales is with different grid sizes, using highly resolved grids in regions where the structure is very fine. This paper describes the use of 3-D adaptive gridding models for pollution transport and reaction using both a layered and a fully adaptive 3-D tetrahedral approach. 相似文献
93.
Magnetic susceptibility can provide rich environmental information, especially for hazardous heavy metals and saline-alkaline in the contaminated soils. Magnetic susceptibility in four vertical profiles from saline-alkaline soils in lower Hai River basin was investigated. Soil sites were extended from alluvial fan to coastal plain areas. They are aligned along a latitudinal strip. Magnetic parameters including low/high frequency susceptibility, frequency-dependent susceptibility was measured. Moreover, some standard pedological parameters such as pH value and organic matter content were also determined. The results showed that low frequency magnetic susceptibility values is very high at the surface and decreases with the profile to a low value. In all profiles from alluvial fan frequency-dependent susceptibility greater than 3% may suggest the presence of relatively more super-paramagnetic particles. Magnetic susceptibility showed obvious vertical distribution in alluvial fan higher than coastal plain. No significant correlations between organic matter, pH and low frequency magnetic susceptibility were found, while there is a negative correlation between organic matter and frequency-dependent susceptibility. A positive correlation between pH and frequency-dependent susceptibility was found in the study areas. 相似文献
94.
The effects of concentration, pH value and ionic strength on the kinetic self-assembly of acid-soluble collagen from walleye pollock (Theragra chalcogramma) skin were investigated. A two-phase kinetic process was provided which included the formation of nucleus center and nucleus growth, the first phase being the controlled step for collagen self-assembly. Collagen showed marked assembly behavior when concentration reaching and above 0.6 mg/mL, and higher concentration could accelerate collagen self-assembly. Rate constants of the first and second assembly phase both increased with pH to a maximum around pH 7.2 and then decreased, indicating that pH 7.2 was the optimum pH value for collagen self-assembly. The kinetics of collagen self-assembly could be modulated by NaCl concentration. The concentration of NaCl from 30 to 60 mM was more suitable to self-assemble for pollock skin collagen. 相似文献
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葡萄酒中邻氨基苯甲酸酯类葡萄香精的高效液相色谱检测方法研究 总被引:1,自引:0,他引:1
以高效液相色谱法建立对葡萄酒中邻氨基苯甲酸酯类(邻氨基苯甲酸甲酯、邻氨基苯甲酸乙酯、N-甲基代邻氨基苯甲酸甲酯)葡萄香精的检测方法。结果表明,3种邻氨基苯甲酸酯类葡萄香精在0.2~50 mg/L范围内均呈良好的线性,相对标准偏差RSD均小于1%,相关系数R2在0.9987~0.9992内,最低检出限可达0.006 mg/L,样品平均回收率在85%~90%之间。 相似文献
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目的:探讨天麻素对D-半乳糖诱导的BV2细胞衰老的保护作用及机制。方法:使用不同浓度(10、20、30和40 μg/mL)的D-半乳糖刺激BV2细胞24 h,建立细胞衰老模型,并用CCK-8法筛选出D-半乳糖的最佳造模浓度;实验分为4组:正常组、模型组、Silent mating type information regulation 2 homolog 3(SIRT3)抑制剂+天麻素组和天麻素组;用CCK-8法检测不同浓度(10、20、30、40和50 μmol/L)的天麻素对D-半乳糖刺激的BV2细胞活力的影响,并筛选出最佳的天麻素浓度;使用β-半乳糖苷酶(Senescence β-Galactosidase,SA-β-Gal)染色检测细胞衰老面积;使用生化法检测各组细胞活性氧(Reactive oxygen species,ROS)水平;使用Enzyme linked immunosorbent assay(ELISA)法检测各组细胞神经炎症因子IL-1β(Interleukin 1β,IL-1β)、IL-6(Interleukin 6,IL-6)和TNF-α(Tumor necrosis factor α,TNF-α)水平;使用免疫荧光法检测各组细胞SIRT3荧光强度;使用Western Blot法检测细胞SIRT3、P16和P21的蛋白表达水平。结果:30 μg/mL的D-半乳糖刺激BV2细胞活力极显著降低(P<0.01),引起BV2细胞中SA-β-Gal染色面积和衰老蛋白P16和P21表达极显著增加(P<0.01),细胞中ROS水平和炎症因子IL-1β、IL-6和TNF-α水平极显著增高(P<0.01),细胞内SIRT3蛋白表达极显著降低(P<0.01)。而30 μmol/L天麻素能极显著提高D-半乳糖刺激的BV2细胞活力(P<0.01),并且极显著降低细胞SA-β-Gal染色面积和衰老蛋白P16和P21表达水平(P<0.01),极显著降低ROS水平和神经炎症因子IL-1β、IL-6和TNF-α水平(P<0.01),极显著提高细胞内SIRT3蛋白荧光强度和表达水平(P<0.01)。结论:天麻素能够提高D-半乳糖刺激的BV2细胞活力,改善BV2细胞衰老染色和衰老蛋白表达,并降低ROS水平和减缓炎症反应,这可能与天麻素提高SIRT3蛋白表达有关。 相似文献
100.