种植沙生植物--沙棘改善内蒙古地区生态环境

结合内蒙古地区现状，对沙棘的生物学和生态学特性、沙棘属植物化学成分和微量元素及种植沙生植物——沙棘的重要性和必要性进行了详细的研究和探讨。研究表明，沙棘属植物具有极强的生态适应性并富含多种营养成分和生物活性物质，并以耐干旱、耐瘠薄、萌蘖及固氮能力强等特点被称为治理非宜林地水土流失、改善生态环境的先锋树种。种植沙棘是治理内蒙古脆弱生态环境最经济、最有效的措施，是贫瘠的不毛之地发展经济、增加收入的经济树种。另外．种植沙棘的技术简便，容易掌握，投资少，见效快。     

内蒙古地区天然植物沙棘果中黄色素的提取工艺及性质研究

以内蒙古地区沙棘果实为原料，研究了提取黄色素的工艺条件，同时对该色素的性质进行了初步探讨。结果表明，以95％的乙醇溶液作浸提剂，提取的黄色素浓度最高，工艺流程简单易行，且无毒，无污染。对提取的黄色素进行的性质试验表明，沙棘黄色素对光、热具有较好的稳定性，适用于酸性或弱碱性的食品中，葡萄糖、氧化剂(H2O2)、还原剂(Na2SO3)等食品添加剂均无明显影响以上结果为这种优良天然色素的开发与应用提供了参考。     

Solid-Phase Synthesis of a Monofunctional trans-a(2)Pt(II) Complex Tethered to a Single-Stranded Oligonucleotide

Cross-linking ability is possible with the oligonucleotide-tethered, monofunctional trans-Pt(II) complex shown. It was synthesized by a novel solid-phase approach comprising conjugation of immobilized tetrathymidylic acid with a trans-a(2)Pt(II) building unit, ammonolysis, and transformation of the resulting complex (R=1-N-cyclohexylmethylthyminate) into the chloro derivative (R=Cl). a=NH(2)CH(3), T=thymine.     

A Rapid HPLC Determination of C2–C7 Aliphatic Diamines by Precolumn Derivatization with Acetylacetone in Methanol-Water

A rapid reversed-phase high performance liquid chromatographic analysis for the determination of seven aliphatic diamines in water is described. Precolumn derivatization with acetylacetone is used for traces of aliphatic diamines in water-methanol (10:1 v/v) medium. The acetylacetone derivatives obtained after 15 min were extracted with an octadecylsilane functionalized silica cartridge, and then injected into the HPLC system. The HPLC system consisted of a reversed-phase column, and a spectrophotometric detector adjusted to 310 nm as elution solvent a methanol-tetrahydrofuran-water (55:3:42 v/v) mixture was used. The acetylacetone derivatives of the C2-C7 diamines were separated with a good resolution in 23 min. The detection limits achieved for each diamine were between 0.18-0.72 ng/ml for a 100 ml water sample. The recovery of diamine derivatives from river and seawater was 88-101%, with relative standard deviations of 2.2-4.0%, and 82-93%, with relative standard deviations of 2.8-4.6%, respectively. Aliphatic diamines are widely used as chemical reagents, occur as metabolic in biomedical studies and are used as chelating agents in analytical chemistry. As they are soluble in water, their use results in their ultimate release to the environment. The need for a sensitive, selective and rapid determination of aliphatic diamines in environmental samples thus has become important. Dobberpuhl et al. [1] have described a highly sensitive pulsed electrochemical detection for aliphatic monoamines and diamines following their chromatographic separation. Although, it is a sensitive method the determination has to be carried out in alkaline conditions. The most common method for the determination of aliphatic amines is high performance liquid chromatography (HPLC), using different derivatives with either fluorescence [2-5] or UV-visible detection [6-11]. The fluorescence detection method most often relies on post-column derivatization, which requires a second pump to deliver the reagent. Acetylacetone is soluble to some degree in water, and has been used as a pre-column derivatization reagent [12]. The reaction only is effective with diamines, and results in UV-active acetylacetone derivatives known as Schiff bases. But acetylacetone requires a long reaction time in water, which makes it rather unsuitable for routine analysis. In this paper an optimized reversed-phase HPLC determination procedure for C2-C7 aliphatic diamines at low ng/ml levels in water is described.     

A simple flow injection spectrophotometric determination method for iron(III) based on O-acetylsalicylhydroxamic acid complexation

A simple and rapid flow-injection spectrophotometric method for the determination of iron(III) and total iron is proposed. The method is based on the reaction between iron(III) and O-acetylsalicylhydroxamic acid (AcSHA) in a 2 % methanol solution resulting in an intense violet complex with strong absorption at 475 nm. Optimum conditions for the determination of iron(III) and the interfering ions were tested. The relative standard deviation for the determination of 5 μg L⁻¹ iron(III) was 0.85 % (n = 10), and the limit of detection (blank signal plus three times the standard deviation of the blank) was 0.5 μg L⁻¹, both based on the injection volumes of 20 μL. The method was successfully applied in the determination of iron(III) and total iron in water and ore samples. The method was verified by analysing a certified reference material Zn/Al/Cu 43XZ3F and also by the AAS method.     

Temperature and pressure dependence of the rate coefficient for the reaction between ClO and CH3O2 in the gas-phase

A temperature and pressure kinetic study for the CH(3)O(2) + ClO reaction has been performed using the turbulent flow technique with a chemical ionisation mass spectrometry detection system. An Arrhenius expression was obtained for the overall rate coefficient of CH(3)O(2) + ClO reaction: k(10)(T) = (1.96(?0.24)(+0.28)) × 10(-11) exp[(-626 ± 35)/T] cm(3) molecule(-1) s(-1) where the uncertainty associated with the rate coefficient is given at the one standard deviation level. Over a range of pressure (100-200 Torr) and temperature (298-223 K) no pressure dependence is observed. The smaller rate coefficients measured at lower temperatures compared with both previous low temperature studies are believed to arise through the reduction of secondary chemistry and greater sensitivity in terms of reactant detection (hence much lower initial concentrations were employed). These new data reduce the effectiveness of ozone loss cycles involving reaction of CH(3)O(2) + ClO in the polar stratosphere by around a factor of 1.5 and restrict the importance of the reaction to the tropical and extra-tropical clean marine environments in the troposphere.     

Determination of gas-phase ozonolysis rate coefficients of a number of sesquiterpenes at elevated temperatures using the relative rate method

The rates of ozonolysis of four sesquiterpenes, β-caryophyllene, α-humulene, isolongifolene and α-cedrene, are determined in the gas phase at an elevated temperature of 366 ± 3 K and a pressure of ~780 Torr using the EXTreme RAnge chamber (EXTRA). The experimentally obtained rate coefficients agree with extrapolated room temperature rate coefficients for isolongifolene and α-cedrene but not for β-caryophyllene and α-humulene, which were found to be three orders of magnitude slower than this in the literature. These new measurements support the hypothesis that operating under ambient conditions, kinetic measurements of condensable species can be influenced adversely by heterogeneous processes and should therefore be treated with caution.