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11.
12.
Effects of seed aerosols on the growth of secondary organic aerosols from the
photooxidation of toluene 总被引:3,自引:0,他引:3
Hydroxyl radical (.OH)-initiated photooxidation reaction of toluene was carried out in a self-made smog chamber. Four individual seed aerosols such as ammonium sulfate, ammonium nitrate, sodium silicate and calcium chloride, were introduced into the chamber to assess their influence on the growth of secondary organic aerosols (SOA). It was found that the low concentration of seed aerosols might lead to high concentration of SOA particles. Seed aerosols would promote rates of SOA formation at the start of the reaction and inhibit its formation rate with prolonging the reaction time. In the case of ca. 9000 pt/cm^3 seed aerosol load, the addition of sodium silicate induced a same effect on the SOA formation as ammonium nitrate. The influence of the four individual seed aerosols on the generation of SOA decreased in the order of calcium chloride〉sodium silicate and ammonium nitrate〉ammonium sulfate. 相似文献
13.
G. Suresh H. C. Kamath Mallikarjun Bhovi 《International Journal of Sustainable Engineering》2016,9(3):206-214
Increased petroleum prices, increased threat to the environment from exhaust emissions and global warming have generated intense international interest in developing renewable and alternative non-petroleum fuels for internal combustion engines. Evolving suitable technology for addressing energy crisis creates a continued investigation into the search for sustainable and clean-burning renewable fuels. This work investigates suitability of different non-edible-derived biodiesels such as cotton seed oil methyl ester (COME), Honne oil methyl ester (HnOME) and Rubber seed oil methyl ester (RuOME) to four stroke, single cylinder compression ignition (CI) engine. Engine tests were conducted to study the effect of fuel blending, thermal barrier coating (TBC) or Low Heat Rejection (LHR) and injector nozzle geometry on the performance, combustion and emission characteristics of COME, HnOME and RuOME in the modified CI engine. Blends of biodiesels with diesel were varied from 20 to 80% in steps of 20%. Two thermal barrier coatings of partially stabilized zirconium (PSZ) and aluminium oxide (Al2O3) were provided on the engine to make it fully adiabatic. Nozzle injectors of 3, 4 and 5 holes, with size of orifice varied from 0.2 to 0.3 mm size were selected for the study. It was concluded that B20 biodiesel blend, PSZ-coated engine and four hole nozzle injector of 0.2 mm size resulted in overall better engine performance with increased brake thermal efficiency (BTE) and reduced HC, CO, smoke emissions for the fuel combinations tested. Combustion analysis to study the effect of biodiesel blends, LHR coatings, injector nozzle geometry on the performance of the biodiesel-fuelled engine has been presented to give more insight into the behaviour of operation. 相似文献
14.
施肥与秸秆还田对太湖稻-油复种系统春季杂草群落特征的影响 总被引:5,自引:0,他引:5
掌握不同管理模式下稻田杂草群落特征,可以为杂草综合防治及农田生物多样性的保持提供理论依据和技术途径。借助稻-油复种系统长期定位施肥试验(江苏吴江,始于1987年),于2007年春季监测长期不同施肥和秸秆还田对农田杂草群落的影响。施肥与秸秆还田对春季稻田杂草群落结构特征存在显著作用。长期有机无机肥配合施用下(化肥+猪粪+秸秆)杂草生物多样性和生物量均下降;长期不施氮肥下杂草总密度显著增高,达1 810 ind./m2;长期不施肥时,田间野老鹳草成为优势种群,其相对密度达879%;全年秸秆还田(化肥+油菜秸秆+水稻秸秆)下,田间优势杂草种群为禾本科的看麦娘,其相对密度达697%;秋熟水稻秸秆还田下杂草生物量下降,而生物多样性显著提高。上述结果表明,通过合理施肥和秸秆还田措施,可以对稻油复种模式中春季杂草群落进行有效调控。 相似文献
15.
E. L. Zheleznaya 《Russian Journal of Ecology》2009,40(1):39-43
The overgrowing of meadow-bog communities by shrubs and trees (age 5–40 years, crown closure 0.4–0.9) leads to a decrease in incident illumination. As a consequence, juvenile and generative plants disappear from D. incarnata population loci, their average ecological density decreases, and the loci enter the state of regression. The digging activity of wild boars disrupts phytocenotically closed groups of longirhizomatous herbs, thereby creating favorable conditions for seed reproduction of D. incarnata. The species begins to form population loci with a complete ontogenetic spectrum and high ecological density, eventually restoring the normal (definitive) population structure. 相似文献
16.
利用人工气候箱研究了抽穗期低温对杂交晚粳新组合宁67A/K1722开花量、包颈率及结实率的影响。结果表明:低温使抽穗速度明显变慢,开花量减少,包颈率呈现上升趋势,不同温度处理对结实率的影响不同,17℃与21℃处理间差异极显著,而19℃与21℃间差异不显著,不同时期处理及不同处理天数(3d,5d,7d和12d)间结实率差异不显著,表明该组合对抽穗期低温的耐受力较强,对抽穗期耐低温的鉴定指标问题进行了讨论。 相似文献
17.
论中国种子植物特有属在台湾的分布 总被引:1,自引:0,他引:1
通过对台湾产的12个中国种子植物特有属即青钱柳属Cyclocarya,通脱木属Tetrapanax,华参属Sinopanax,八角莲属Dysosma,棱果花属Barthea,棱果茜属Hayataella,银脉爵床属Kudoacanthus,异叶苣苔属Whytockia,毛药花属Bostrychanthera,泡果荠属Hilliella,悬竹属Ampelocalamus.井岗寒竹属Gelidocalamus等的地理分布分析,发现台湾产的中国种子植物特有属具有衍生性质,属于次生的成分. 相似文献
18.
Inna P. Solyanikova Nataliya E. Suzina Nataliya S. Egozarian Valentina N. Polivtseva Nataliya V. Prisyazhnaya Galina I. El-Registan 《Journal of environmental science and health. Part. B》2017,52(10):745-751
This work was aimed at studying the response of soil non-spore-forming actinobacterial strain Arthrobacter agilis Lush 13 to changing natural conditions, such as nutrient availability and the presence of degradable and recalcitrant aliphatic and aromatic substrates. The A. agilis strain Lush13 was able to degrade octane, nonane, hexadecane, benzoate, phenol, and 2,3-, 2,4-, 2,5-, 2,6-dichlorophenols, but not grew on 3,4-dichlorophenol, 2,3,4-, 2,4,5-, 2,4,6-trichlorophenol (TCP), pentachlorophenol (PCP), 2-chlorobenzoate, 3-chlorobenzoate, 3,5-dichlorobenzoate, 2,4-dichlorobenzoate. Under growth-arresting conditions due to nitrogen- or multiple starvation or recalcitrant (non-utilizable) carbon source, the studied strain preserved viability for prolonged periods (4–24 months) due to transition to dormancy in the form of conglomerated small and ultrasmall cyst-like dormant cells (CLC). Dormant cells were shown to germinate rapidly (30 min or later) after removal of starvation stress, and this process was followed by breakdown of conglomerates with the eliberation and further division of small multiple actively growing daughter cells. Results of this study shed some light to adaptive capabilities of soil arthrobacters in pure and polluted environments. 相似文献
19.
快腐剂对畜禽粪便堆肥过程中腐熟度的影响 总被引:5,自引:0,他引:5
以牛粪、菌糠和鸡粪等为材料按照两种比例调配为混合基质,在添加或不添加快腐剂的条件下在发酵桶中进行为期38 d的堆肥发酵实验,通过对发酵产物的温度、p H值、总有机碳、C/N、硝铵态氮含量和种子发芽指数等指标变化的研究,揭示了快腐剂对发酵过程的影响。结果表明,虽然快腐剂对有机物料的温度、C/N比无显著的影响,但可以促进铵态氮向硝态氮的转化,在16 d时使发酵产物NH+4-N/NO-3-N比值降为0.15,达到腐熟标准(0.16);提升种子发芽指数,在腐解29 d时使种子发芽指数达到82.76%,达到完全腐熟指标(0.8),比不添加快腐剂的处理提前了4 d左右。快腐剂的作用效果受腐解物料配比的影响。 相似文献
20.