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131.
以黄渤海上空大气为目标研究区,基于AERONET观测网,获取该区域2015—2017年的气溶胶光学厚度(AOD)实测数据,并对可见红外成像辐射计VⅡRS,中分辨率成像光谱仪MODIS,静止水色卫星成像仪GOCI与新一代地球同步气象卫星AHI H8的AOD遥感产品展开精度验证.同时,利用长时间的遥感影像探究并分析AOD在不同时空尺度下的分布特征与变化情况.结果表明:同其它AOD遥感产品相比,GOCI AOD展示出了高采样频率及高精度的特性.此外,在研究区域AOD的逐小时遥感影像中未发现明显的变化规律,而月平均图则显示出从黄渤海西部至中部再到东部AOD逐渐递减的趋势,且该趋势在研究区域不同的地方是具有差异的.不仅如此,本文还尝试分析影响AOD反演精度的潜在因子,发现其可能与地表反射率提取的准确度与预设气溶胶模型设置的合理性有关.  相似文献   
132.
This study assesses the effect of NaCl (80 and 160 mM) and CaCl2 (10 mM) solutions, alone and in combination, to 30-day-old seedlings of Cichorium intybus L. Observations were made at 30 day intervals from the time of treatment till harvest (180 days after sowing). Application of NaCI resulted in significant decreases in lengths of root and stem, in dry weights of root, stem and leaves and in the leaf area, as compared with control. The reduction was less with the combined application of NaCI and CaCI2 than with the NaCI treatment alone. On the contrary treatment of CaCl2, alone promoted the above variables. Proline content in the leaves was enhanced with NaCl and CaCI, alone as well as with the NaCI + CaCI2 treatments; the maximum (six-fold) enhancement was observed with the combined treatments, compared with NaCl (four-fold increase) and CaCl2 (two-fold increase) alone. The sodium (Na+) and Chloride (CI) contents in different plant parts increased both with NaCI and with NaCI+ CaCI2 treatments. The maximum accumulation was observed in leaves, followed by that in stem and root. The potassium (K+) and calcium (Ca2+) contents decreased under NaCl stress, but increased with CaCI2 treatment. Thus, calcium ameliorated the deleterious effects of NaCI stress and stimulated the plant metabolism and growth.  相似文献   
133.
The selective catalytic reduction (SCR) rate of NO with N-containing reducing agents can be enhanced considerably by converting part of NO into NO2. The enhanced reaction rate is more pronounced even at lower temperatures by using an equimolar mixture of NO and NO2 (fast SCR reaction). The oxidation characteristics of NO over catalyst Pt/TiO2 have been determined in a fixed bed reactor (8 mm-ID) with different concentrations of oxygen, nitric oxide and nitrogen dioxide in the presence of 8% water. The conversion of NO to NO2 increases with increasing oxygen (O2) concentration from 3 to 12%, but it levels off at higher O2 concentrations. The NO conversion to NO2 decreases with increasing NO concentration and it also decreases by an addition of NO2 in the feed stream. Therefore, the oxidation of NO over Pt/TiO2 catalyst could be auto-inhibited by the reaction product of NO2. The effects of CO and SO2 on NO oxidation characteristics have also been determined. In fact, the presence of SO2 significantly suppresses oxidation of NO but due to the less stability of sulfate on anatase structure in TiO2, it becomes less significant. On the other hand, the presence of CO increases NO oxidation significantly due to the auto-inhibition effect by CO. Moreover, the effect of SO2/CO on NO oxidation has also been determined and it was observed that NO oxidation decreases with the increase in SO2/CO ratio.  相似文献   
134.
The ability of cadmium uptake by metal-resistant yeast, Candida tropicalis, from the liquid medium and wastewater was evaluated. The minimum inhibitory concentration of Cd2?+? against C. tropicalis was 2,500 mg L???1. The yeast also showed tolerance toward Zn2?+? (1,400 mg L???1), Ni2?+? (1,000 mg L???1), Hg2?+? (1,400 mg L???1), Cu2?+? (1,000 mg L???1), Cr6?+? (1,200 mg L???1), and Pb2?+? (1,000 mg L???1). The yeast isolate showed typical growth curves, but lag and log phases extended in the presence of cadmium. The yeast isolate showed optimum growth at 30°C and pH 8. The metal processing ability of the isolate was determined in a medium containing 100 mg L???1 of Cd2?+?. C. tropicalis could decline Cd2?+? 70%, 85%, and 92% from the medium after 48, 96, and 144 h, respectively. C. tropicalis was also able to remove Cd2?+? 40% and 78% from the wastewater after 6 and 12 days, respectively. Cd produced an increase in glutathione (GSH) and nonprotein thiol levels by 135% and 134% at 100-mg L???1 concentration, respectively. An increase in the synthesis of GSH is involved in metal tolerance, and the presence of increasing GSH concentrations may be a marker for high metal stress in C. tropicalis. C. tropicalis, which is resistant to heavy metal ions and is adaptable to the local environmental conditions, may be employed for metal detoxification operations.  相似文献   
135.
Food and Environmental Virology - Drinking water supplies in the developing world often serve as a biosphere for various organisms. Viral gastroenteritis is a neglected area of research in...  相似文献   
136.
Journal of Polymers and the Environment - In this study, carboxymethyl chitosan with gum Arabic (CG) based novel functional films containing Cinnamomum camphora seeds extract (CCSE) at varying...  相似文献   
137.
Environmental Fluid Mechanics - The principle theme of this study is to introduce a novel countermeasure to reduce the energy of the overflowing floodwater by utilization of a water cushion. For...  相似文献   
138.

Polymer materials are vulnerable to damages, failures, and degradations, making them economically unreliable. Self-healing polymers, on the other hand, are multifunctional materials with superior properties of autonomic recovery from physical damages. These materials are suitable for biomedical and tissue engineering in terms of cost and durability. Schiff base linkages-based polymer materials are one of the robust techniques owing to their simple self-healing mechanism. These are dynamic reversible covalent bonds, easy to fabricate at mild conditions, and can self-reintegrate after network disruption at physiological conditions making them distinguished. Here we review self-healing polymer materials based on Schiff base bonds. We discuss the Schiff base bond formation between polymeric networks, which explains the self-healing phenomenon. These bonds have induced 100% recovery in optimal cases.

  相似文献   
139.
Environmental Science and Pollution Research - COVID-19, declared by the World Health Organization (WHO) to be a pandemic, has affected greenhouse gas emissions and contributed to the uncertainty...  相似文献   
140.
Environmental Science and Pollution Research - Climate change is a long-lasting change in the weather arrays across tropics to polls. It is a global threat that has embarked on to put stress on...  相似文献   
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