用Origin 6.0绘制波函数立体图形

Origin6．0作为一个数学软件平台，具有数据管理与分析、二维及三维函数和离散数据绘图、程序开发等多种功能，广泛用于工程设计和科学研究。本文利用Origin6．0软件的三维函数绘图功能，绘制势箱波函数、氢原子轨道、及其电子云密度函数的立体图形、等值线图和等密度线图。详细给出了各类绘图函数的程序可读化形式、图形及操作过程。该绘图方法操作界面更友好，适用于一般化学化工过程中的三维解析函数可视化。     

中国酸雨的过去、现在和将来

从80年代以来,中国的酸雨污染呈加速上升趋势.继欧洲和北美之后,中国出现了世界第三大酸雨区.中国的酸雨主要发生在长江以南,青藏高原以东地区和四川盆地.中国形成酸雨的两种主要机制是大气致酸污染物 的局地冲刷和中长距离传输.根据对致酸污染物未来排放量的预测,中国的酸雨区在2020年以前将继续扩大.     

塔里木,准噶尔盆地石油生成与演化

以塔里木、准噶尔盆地干酪根、沥青的Ｐｂ、Ｓｒ、Ｎｄ同位素分析资料，回答了地质学家必须回答的四个问题：①石油是由舒什么生成的；②石油是如何生成的；③石油是地何时生成的；④石油是何时运移的。根据Ｐｂ、Ｓｒ、Ｎｄ同位素所揭示的信息指出，塔里木、准噶尔盆地的石油虽然是在不同构造背景下生成的，生油模式、生油年龄和运移年龄也不相同，但都是由费托合成反应无机生成的。作者指出，地救化学急变对油气田分布的控制作用十     

客家土楼中的象征文化浅析

客家土楼以其鲜明的风格成为世界建筑艺术的一朵奇葩,其中蕴含着丰富的象征文化.试从象征的源起及在建筑中的具体体现等方面,对客家土楼中的象征文化进行诠释.通过研究其中的象征文化,有助于更完整地认识客家土楼建筑文化的全部涵义.     

The value of quality clues in the wine market: evidences from Lazio,Italy

The purpose of the paper is to contribute to understanding the role and effectiveness of different quality clues in the creation of value for the main wines of the Lazio region. The study presents a hedonic price model. An ordinary least squares and a quantile regression models were estimated. The latter is able to detect additional patterns related to the effects of the covariates. Prices are regressed on wine color, sub-regional area of origin, the type of certification of origin, and on experts' evaluation. The analysis is based on data released by three major Italian wine guides: Gambero Rosso, l'Espresso, and AIS (Italian Sommelier Association). Results show that: (i) white and red wines follow two different price patterns; (ii) prices are correlated with experts' evaluation; (iii) the impact of the latter is higher when other quality clues, such as geographical indications, are less effective; (iv) the role of different quality clues varies at different price levels and it is different for red and white wines; overall, wines from the Lazio region are associated with poor to mediocre quality levels. This may explain the decline in reputation and in market share that these wines are experiencing after centuries of popularity.     

Willingness to pay for red wines in China

China's rapidly expanding wealthy population has expressed a new desire for imported red wines. Using data collected in China's major red wine consumption region of Beijing, this study analyzes the impact of country of origin, price, wine age, and brand on consumer-derived utility and willingness to pay for red wines. Findings from a conditional logit model and a mixed logit model indicate that price remains the key factor in Chinese consumers' red wine choices. For gift purchases, consumers are willing to pay an additional $20 to move from a US wine to a French wine. For own consumption, French wines are preferable if their price is within a reasonable range of $13–20 above Chinese or US wines. Chinese consumers also strongly favor branded and matured red wines. China's rapid and sustainable economic growth and its stronger integration to the global economy have led to greater disposable income and the expanding consumer demand for luxury beverage of red wines.     

Entomological authentication of stingless bee honey by 1H NMR-based metabolomics approach

The high value of stingless bee honey, better known as pot-honey, offers an incentive to fraud and requires new analytical methods to guarantee the entomological origin. In this research, Geotrigona-Trigona, Melipona, Scaptotrigona, and Apis mellifera Ecuadorian honeys were analyzed. Orthogonal projection to latent structure-discriminant analysis (OPLS-DA) built on ¹H NMR data obtained by both water dilution and chloroform extracts spectra, conveyed to successful entomological discrimination. The metabolic fingerprints of these different types of honeys are unique. The most important findings are specific marker signals of entomological origin in chloroform extracts: metabolites deriving from the cerumen secreted by the same bees are present and may be considered as the bee species signature on honey. Furthermore, the endogenous diacylglyceryl ether is recognized as the key marker of pot-honey adulteration with Apis mellifera honey.     

混凝土工程裂缝控制

通过对混凝土裂缝长期的观察和研究,从结构性裂缝和非结构性裂缝两个方面入手,阐述了裂缝的发生、发展和补救方法,并制定了有针对性的预控方案,以确保建筑物和构件安全。     

Asymmetric Autocatalysis Triggered by Chiral Crystals Formed from Achiral Compounds and Chiral Isotopomers

Asymmetric autocatalysis with amplification of enantiomeric excess is found in the enantioselective addition of diisopropylzinc to pyrimidine-5-carbaldehyde using pyrimidyl alkanol as an asymmetric autocatalyst. Asymmetric autocatalysis has been employed as a method for clarifying the origin of homochirality. Circularly polarized light, inorganic chiral crystals and statistical fluctuation of enantiomeric imbalance act as chiral initiators in asymmetric autocatalysis to afford highly enantioenriched products. We have investigated asymmetric autocatalysis using chiral crystals formed from achiral and racemic compounds as an origin of chirality. Absolute control of the crystal chirality of cytosine was achieved by the removal of crystal water. Enantioselective carbon-carbon bond formation at the enantiotopic crystal face of aldehydes was established using diisopropylzinc vapor. In addition, asymmetric autocatalysis triggered by chiral compounds arising from H, C and O isotope substitution has been achieved.