Forchheimer方程对物理参量的连续依赖性

研究了一类Forchheimer方程的解的结构稳定性问题,通过证明得到:Forchheimer方程的解对粘性系数γ是连续依赖的,也就是说,当γ变化很小时,其解的变化也很小.     

二阶中立型泛函微分方程非振动解的存在性定理

本文研究了一类二阶中立型泛函微分方程非振动解的存在性、所得结论回答了如何建立中立型方程的非振动解的存在准则问题.     

众皆竞进以贪婪兮余独好修以为常一一从《离骚》看屈原的人格美

屈原是中国历史上第一位伟大诗人，其代表作《离骚》是中国文学史上最长的一首自传体政治抒情诗。长诗在不断加强自我修养、执著追求进步政治理想、毫不妥协地进行斗争、热爱和忠于自己祖国等方面表现了屈原的人格美，其意义在于唤起麻木灵魂的警醒与自觉，培养人们高尚纯洁的品格和爱国主义情感。     

一类椭圆型方程组非负重整化解的不存在性

利用比较原理和反证法,证明了一类椭圆型方程组非负重整化解的不存在性。     

放逐理想 顺应现实——简论池莉小说的价值取向

放逐理想,顺应现实是池莉小说创作的基本理念和价值取向。池莉小说中的人物面对种种生存困境不是选择反抗和超越,而是选择顺应和妥协。这使她的小说缺乏真正意义的悲剧精神和深沉的忧患意识,仅仅停留在平和温情的世俗关怀层面。     

Productivity of deciduous woody and fodder species in relation to air temperature and precipitation in a Mediterranean environment

Productivity and its relation to air temperature and precipitation of 11 deciduous woody fodder species was studied in a semi-arid Mediterranean environment with cold winters in Macedonia, Greece. The species studied included six shrubs: Amorpha fruticosa L., Carpinus orientalis Mill, Colutea arborescens L., Corylus avellana L., Fraxinus ornus L. and Ostrya carpinifolia Scop.; and four trees: Pirus amygdaliformis Vill., Quercus pubescens Wild., Quercus sessiliflora Salish. and Robinia pseudoacacia L., with two accessions, common and spineless. Fodder species were established as one-year-old seedlings in 1987 and studied through 1994. Productivity was measured by clearcutting of the aboveground annual biomass (DM) at the end of each growing season. Samples of biomass were hand separated to determine the grazeable material (leaves and twigs). In addition, monthly values of air temperature and precipitation were correlated with annual biomass through a multiple linear regression analysis. It was found that annual biomass was statistically different among species in all the study years with Robinia being the most productive of all the species tested followed by the other two legumes Colutea and Amorpha. Proportion of grazeable material ranged widely among species and years with an overall mean of 50%. Robinia produced grazeable biomass more than 1000 kg/ha followed by Amorpha and Colutea with about 800 and 700 kg DM/ha, respectively, while all the other species produced less than 500 kg DM/ha. Yearly variation in annual biomass was found to be affected much more by air temperature, especially during the beginning of the growing season (March), than by precipitation. Coefficients of determination (r ²) were found to be high (0.50–0.80) in Amorpha, Pirus, Quercus and Robinia but only in the latter two species they were high enough (>0.70) so that the relations produced can be used for predictive purposes. This revised version was published online in June 2006 with corrections to the Cover Date.     

试析李大钊的图书馆学思想

李大钊的图书馆学思想是我国图书馆事业宝贵的遗产,是中国图书馆学思想的一部分,对现代图书馆有着深远的影响。在当今图书馆向数字化、网络化和虚拟化方向发展的历史时期,李大钊的图书馆学思想仍值得我们研究、学习和借鉴。     

重庆地区板栗园桃蛀螟发生与为害调查及药效试验

2001-2002年，对桃蛀螟在重庆地区板栗园的生活史、发生规律、生活习性、为害特点及其化学防治进行了研究。结果显示，桃蛀螟在重庆地区的生活史为每年发生4代，是重庆地区板栗园引起果实减产最主要的蛀果性害虫；7种药剂的药效试验表明，5.0％抑太保乳油和2.5％功夫乳油对桃蛀螟的防效较好。     

复共线联立方程模型参数的修正间接岭估计

在结构方程恰好被识别时，研究了外生变量设计矩阵X复共线时联立方程模型的参数估计问题，提出了参数的一种修正间接岭估计方法，并证明了这种参数估计的良好统计性质，最后给出了在修正间接岭估计均方误差最小意义下岭参数的一种选择方法.     

一类中立型泛函微分方程的振动解的存在性

本文主要考虑了中立型泛函微分方程振动解的存在性,得到了该微分方程有界振动解和无界振动解的充分条件。