新城疫热稳定性天然弱毒株B95生物学与免疫学特性初步研究

新城疫病毒Ｂ９５（ＮＤＶＢ９５）是从国外引进的一株稳定性的天弱毒株。本项研究证明：本毒株对鸡 鸡无毒副作用,ＩＣＰＩ和ＩＶＰＩ值分别为０;该病毒可凝集鸡、鸭、牛、绵羊、鹅、猪、小白鼠和人的红血球,血凝价与Ｉ系、ＨＢ１和Ｌａｓｏｔａ相似将病毒置５６℃２ｈ,置３７℃保存１０ｄ,仍见有血凝性和对鸡胚感染性;经点眼、饮水、非免疫鸡与免疫鸡同居,均能获得好的免疫效果,并能耐受新城疫强毒株的攻击。     

简单电力系统运行中的浑沌现象

In this paper,the static stable process of one machine to infinite bus power system under small disturbance was analysed. Based on the related nonlinear swing equations, modern dynamic system theory was applied to the analysis of this static stable proces     

Influence of Biopost and Organo upon Flue-cured Tobacco Grown on Semigley I. Leaf Yield and Participation of Particular Tobacco Classes

Investigations were carried out on semigley in the central River Drava valley (Northern Croatia) with the aim of establishing the fertilizing value of biopost, as a representative of organic fertilizers, and of organo, as a representative of organic-mineral fertilizers, in comparison with mineral fertilizers and stable manure, the latter two being compared with each other as well regarding the yield and quality of flue-cured tobacco leaf. Efficiency of the fertilizer types and rates applied was strongly affected by very adverse meteorological conditions, which often showed characteristics of severe drought. Nevertheless, under such conditions and despite the minimum rates applied, biopost and organo had a positive effect on the yield and quality of the flue-cured tobacco leaf. In all cases, they had an obvious advantage over mineral fertilization, offering distinct possibilities of their application in the growing of flue-cured tobacco. However, owing to its better fertilizing efficiency, combined organic and mineral fertilization might be justified, certainly also with respect to the economic aspect of the problem. The positive influence of biopost and organo on the higher participation of quality classes of flue-cured tobacco leaf in comparison with mineral fertilization is indisputable despite the occasionally prevailing effects of fluctuating weather conditions during the investigation period. In other words, harmonic organic, even organic-mineral, fertilization should be preferred to mineral fertilization alone.     

Convergence of Ishikawa Type Iterative Sequence With Errors for Asymptotically Quasi-nonexpansive Mappings in Convex Metric Spases

Liu Qihou, in 2001 and in 2002, extended the results of Petryshgh and Williamson, Ghosh and Debnath respectively in 1973 and in 1977, proved some sufficient and necessary condition for Ishikawa iterative sequence and for Ishikawa iterative sequence with error member of asymptotically quasi-nonenpansive mappings to converge to fixed poind in Banach space and in uniform convex Banach space. In convex metric spaces,the Ishikawa iteration process with errors is defined for asymptotically quasi-nonexpansive mappings.Some sufficient and nevessary conditions proved for the iterative schene converges to the fixed point of the asymptotically quasi-nonexpansire mappings.These results qeneralize and unify many important known results in recent literature.     

Soil Amendment Improves Tree Growth and Soil Carbon and Nitrogen Pools in Mongolian Pine Plantations on Post‐Mining Land in Northeast China

Mining activities leave large areas of post‐mining lands to be reclaimed. Increases in soil C and N pools and N availability are important to successfully reestablish trees on post‐mining land. In this study, we determined C and N concentrations and natural stable isotope of ¹³C and ¹⁵N in soil and plant in Mongolian pine (Pinus sylvestris L. var. mongolica Litv.) plantations 8 years after establishment on non‐mined land (NM), post‐mining land without soil amendment (NAM), and post‐mining land with soil amendment (AM) in a placer gold mining region of Northeast China. We found that the growth of Mongolian pine was significantly slower on NAM as compared with NM (decreasing by 73% in tree height and 63% in basal diameter), but tree growth improved on AM. Soil C and N concentrations, plant N concentration, and soil δ¹⁵N value decreased in the order of NM > AM > NAM, implying that soil N availability decreased in post‐mining land, but soil amendment could increase soil N availability. However, the values of δ¹⁵N in plant tissues of Mongolian pine were higher on NAM than on NM and AM, suggesting that soil inorganic N form absorbed by trees might be changed when trees were directly planted on post‐mining land with lower soil N availability. In addition, the values of δ¹³C in 1‐ and 2‐year‐old leaves of Mongolian pine were lowest when planted on NAM, indicating a decrease in intrinsic water‐use efficiency of Mongolian pine. Our results suggest that soil amendment helps us establish forests successfully on post‐mining lands. Copyright © 2015 John Wiley & Sons, Ltd.     

Stable isotope analysis of trophic position and terrestrial vs. marine carbon sources for juvenile Pacific salmonids in nearshore marine habitats

Abstract  Stable isotope analysis was used to determine trophic position and the relative contributions of terrestrial-derived carbon (TDC) and marine-derived carbon for Chinook, Oncorhynchus tshawytscha (Walbaum), pink, Oncorhynchus gorbuscha (Walbaum), and chum, Oncorhynchus keta (Walbaum) salmon fry in near-shore marine habitats. Chum fry were enriched in δ ¹³C relative to pink fry, and enriched in δ ¹⁵N relative to both Chinook and pink fry. Between 5.5 and 39.7% of the carbon in the three species was TDC. The TDC was higher in chum fry (28.7 ± 4% SD) than in pink fry (24.9 ± 4.4% SD), but TDC did not differ between Chinook fry (27.8 ± 9.5% SD) and either chum or pink fry. The fry of these three species of Pacific salmon may form a trophic hierarchy with chum fry occupying the highest trophic position and the three species may also partition resources according to carbon source.     

稳定同位素在植物水分来源及利用效率研究中的应用

介绍了稳定氢、氧、碳同位素技术在定量区分植物水分来源及利用效率研究中的应用。以往大量研究结果表明,由于植物根系在吸收水分过程中没有发生同位素分馏,所以通过比较和分析植物木质部水分及其可利用水源的氢氧同位素δ值,就可以定量判断植物的水源;植物在光合作用过程中会产生碳同位素的分馏,从而使得植物叶片中的碳同位素组成能够成为指示植物水分利用效率的一个间接指标,是目前研究植物叶片长期水分利用效率的最佳方法;稳定同位素技术作为安全的示踪剂,有助于人类了解植物的生理生态功能,随着该技术的不断完善和研究的不断深入,同位素技术将会在生态学研究的许多领域得到广泛的应用。     

密集烘烤关键温度点不同稳温时间对烤后烟叶品质的影响

以K326中部叶为试验材料,研究了关键温度点不同稳温时间对烤后烟叶品质的影响。结果表明,干球温度38℃、42℃、47℃时分别稳温32 h、10 h、20 h,可使烘烤过程干物质消耗减少,烤后烟叶色度更强,内含物中总植物碱含量降低、钾离子含量提高,同时烤后烟叶香味风格有所提升、香气质较好。变黄后期和定色前期分别稳温14 h、16 h不利于烟叶品质的形成。     

基于蒸发皿实验的大气水汽氢氧稳定同位素模拟

大气水汽氢氧稳定同位素直接反映了水在大气中输送、混合和相变等过程的关键信息,通过蒸发皿实验可以模拟大气水汽氢氧稳定同位素组成,但模拟方法的可靠性仍需要实测资料的验证.于2019年9-11月在甘肃兰州进行了蒸发皿实验,对逐日大气水汽氢氧稳定同位素进行模拟,同期利用在线大气水汽氢氧稳定同位素分析仪进行实时监测从而对模拟结果...