标准强化竹豆型营养保健米膳微量元素模式营养评分研究

测定了竹豆营养保健米的Ｚｎ，Ｃｕ，Ｆｅ，Ｍｎ，Ｓｅ含量，作了营养评分，并对该型保健米的科学配膳进行了研究，为改革主食营养结构，防治疾病提供了依据。     

Ditertiary phosphine complexes of (ν-allyl)dicarbonylmolybdenum(II) and -tungsten(II)

Compounds of the type [XM(CO)₂(ν-allyl)L₂] (where X = Cl and Br; M = Mo and W; L₂ = Ph₂PCH₂PPh₂ and Ph₂ PCH₂CH₂PPh₂) have been prepard from the corersponding MeCN complexes. The spectral properties of these compounds and the effects of chelate rign size on ³¹P coordination shifts and J(¹⁸³W—³¹P) have been investigated.     

Application of capillary zone electrophoresis (CZE) to the determination of pathogenic bacteria for medical diagnosis

Microorganisms like bacteria, viruses, fungi, etc. have a major impact on human, animal, and plant life. Several decades ago it was observed that intact cells suspended in an isotonic salt solution moved toward the anode and the mobility was proportional to the density of the charge located on the cell surfaces. Since then, efforts have been made to make electrophoresis a useful tool in cell studies. Microorganisms are no exception. In the present work we applied the capillary zone electrophoresis (CZE) with dynamical modification of the capillary surface for separation of E. coli and P. vulgaris. The same method was used for identification of E. coli in infected urine (direct injection - UTIs) and also for identification of Helicobacter pylori which is a gram-negative bacillus responsible for one of the most common infections found in humans worldwide. Using spectrophotometric measurements at λ = 214 nm we proved that it is possible to measure the concentration of bacterial cells up to 5 × 10⁸ cells/mL. Recent studies have demonstrated very practical uses for electrophoretic techniques, especially in the field of medical diagnosis. Figure The developed CZE method allows the rapid analysis and identification of pathogenic bacteria: example shown illustrates the identifcation of E. coli in a urine sample determined much more rapidly than with conventional culturing on Petri dishes Presented at the 11th International Conference on Chemistry and the Environment, 9–12 September 2007, Torun, Poland.     

Vapor phase infrared spectrum and coriolis coupling constants of pentacarbonyl(thiocarbonyl)chromium(0)

Several band contours have been successfully resolved in the high-resolution IR spectrum of pentacarbonyl(thiocarbonyl)chromium(0) vapor at ~312 K. However, PQR separations are only clearly discernible for the three v(CO) fundamentals (v₁,v₂ and v₁₆). The good agreement between the observed and calculated PR separations of the two a₁v(CO) modes (v₁ and v₂) verifies the C_4v prolate symmetrical top geometry of the molecule. From band shape analyses, the Coriolis coupling constants of the ev(CO) mode (v₁₆) and the e δ (CrCO) mode (v₁₇) are estimated to be —0.45 ± 0.05 and —0.80 ± 0.15, respectively.     

The total syntheses of (±)-α- and β-dihydro-cleavamines, (±)-16-methoxycarbonyldihydrocleavamine, (±)-coronaridine, (±)-dihydrocatharanthine, (±)-ibogamine, (±)-epi-ibogamine and (±)-catharanthine2

The total syntheses of (±)α- and β-dihydrocleavamines, (±)-16-methoxycarbonyldihydro-cleavamine, (±)-coronaridine, (±)-dihydrocatharanthine, (±)-ibogamine, (±)-epi-ibogamine and (±)-catharanthine are described.     

Copper(II)-cetyltrimethylammonium chloride-chromal blue G ternary complex and its application to the spectrophotometric determination of copper(II)

A sensitive spectrophotometric method for the determination of copper(II) based on a ternary complex with chromal blue G, a triphenylmethane reagent in the presence of cetyltrimethylammonium chloride, is described. The sensitivity of color reaction between copper and chromal blue G has been greatly increased by the sensitizing action of cetyltrimethylammonium chloride, a cationic surfactant. The color development of the ternary complex can be utilized in the highly sensitive spectrophotometric determination of copper. The molar absorptivity of the binary complex between copper and chromal blue G ε_630nm = 9.56 × 10³liters · mol⁻¹ · cm⁻¹ is enchanced on ternary complex formation to ε_{542 nm} = 4.78 × 10⁴liters · mol⁻¹ · cm⁻¹. The ternary complex gave a maximal absorbance at 542 nm in the pH range 9.8–11. Beer's law is obeyed up to at least 1.2 ppm of copper. The maximal absorbance of the ternary complex was found to develop within 5 min and then it remains constant for several hours. The formation constant of the ternary complex is calculated to be 8.6 × 10¹⁰ under these conditions.     

Comparison of stir bar sorptive extraction (SBSE) and liquid-liquid extraction (LLE) for the analysis of polycyclic aromatic hydrocarbons (PAH) in complex aqueous matrices

Stir bar sorptive extraction (SBSE) is an equilibrium extraction method used amongst others for the analysis of polycyclic aromatic hydrocarbons (PAH) in aqueous samples. We compared SBSE to liquid-liquid extraction (LLE) for aqueous eluates obtained from batch and column tests of PAH contaminated soils to check whether SBSE might be considered as an alternative sample preparation method. We used soils with different particle size distribution, organic matter content, and resulting eluate turbidity to test the sample preparation methods on eluates with matrices of varying complexity. Furthermore, we studied the influence of diluted organic matter (DOM) on the PAH sorption process to the polymer coating of the stir bar during SBSE. In the majority of cases, we found higher PAH concentrations (up to 288%) with SBSE than with LLE. The turbidity correlates with the difference in PAH results, i.e. the greater the turbidity in the eluate, the more PAH we found with SBSE compared to LLE. We observed no similar trend regarding the amount of total organic carbon (TOC). The presence of DOM in the eluate seems to hamper the SBSE slightly, the PAH recovery varied between 82 and 104%.     

第35届中国化学奥林匹克(初赛)有机试题解析

从反应机理出发,对第35届中国化学奥林匹克(初赛)有机试题进行了解析,以加深读者对竞赛试题的理解,掌握答题方法与技巧,提高学习效率。     

Some observations concerning the direct titration of nitrite with cerium(IV)

Direct titration of nitrite with cerium (IV), with ferroin as indicator, is shown to give satisfactory results if the acidity is kept between 0.033 and 0.055M at the end-point. Loss of nitrous acid owing to volatilization and decomposition is discussed. From 10 to 60 mg of sodium nitrite can be estimated with a standard deviation of 5 mug and an average error of 0.2%.     

Fullerene C60研究进展

简单介绍Fulerene C_(60)的研究史和研究现状,详细介绍Fullerene的主要物性及应用前景。     

Reactive intermediates in the photolysis of cyclopentadienylcobalt(I) dicarbonyl and in the reduction of cyclopentadienylcobalt(III) carbonyl diiodide

Photolysis of (C₅H₅)Co(CO)₂ (I) in toluene or petroleum ether solution at ?78°C generates the unsaturated monocarbonyl species (C₅H₅)Co(CO), which was identified in solution by its IR spectrum. At room temperature, this monocarbonyl can associate with excess I to give (C₅H₅)₂Co₂(CO)₃, or dimerize to (C₅H₅)₂Co₂(CO)₂. The latter is stable as a solid, but in solution it is slowly converted to the insoluble trimer (C₅H₅)₃Co₃(CO)₃. (C₅H₅)₂Co₂(CO)₂ is symmetrically cleaved by phosphines to (C₅H₅)Co(CO)(PR₃), while diolefins bring about unsymmetrical cleavage to give (C₅H₅)Co(diolefin) and (C₅H₅)Co(CO)₂.     

Extraction of Unprotected Amino Acids by Mixed-Ligand Nickel(II) and Copper(II) Chelates

Summary.  Six mixed-ligand Nickel(II) and Copper(II) chelates with square-planar geometry of the formula [Ni/Cu(O-O)(S-tmpn)]B(C₆H₅)₄ were prepared, where O-O represents acetylacetonate, tropolonate, or hinokitiolate and S-tmpn is (S)-tetramethyl-1,2-propanediamine. The compounds were investigated with respect to their function as receptor for unprotected amino acids, taking advantage of their high solubilities in non-polar organic solvents. In liquid-liquid extraction experiments between a 1,2-dichloroethane phase containing the metal chelates and an aqueous phase containing amino acids (rac-phenylglycine, rac-phenylalanine, or rac-tryptophan), the nickel(II) chelates effectively extracted amino acids from the aqueous phases under neutral conditions, forming octahedral ternary chelates. Received February 19, 2001. Accepted April 2, 2001     

Stability constants and thermodynamic functions of Y(III), Rh(III), Sm(III), Gd(III) and Dy(III) with juglone (5-hydroxy-1,4-naphthoquinone)

This work considers how the ratio signal/noise and the introduction of a cut-off frequency affect the calculus of the thermogenesis. In particular, the validity of the experimental criterion used to calculate this frequency inside the deconvolutive calculus is studied. The deconvolutive efficiency of the universal transference function is also presented comparatively.     

第32届中国化学奥林匹克初赛有机试题详解

利用框图全面归纳了第32届全国化学奥林匹克竞赛（初赛）有机试题的考点分布,并对考题进行了详细解析,以帮助致力于参加高中化学竞赛的考生取得优异成绩。     

Laser flash photolysis of fullerols of C_(60) and of C_(70) in aqueous solutions

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气相色谱法用于观察手性醇合成中的对映体选择性自动诱导效应

在手性醇合成中,采用非手性柱气相色谱（ＣＣ）分析,结合反应前后诱导物和产物的比旋光度测定,简单方便地计算了比旋光增量;以这种方法,成功地观察到了手性化合物选择性自动诱导效应。     

A reappraisal of the nature of the product from the reaction of bis(methylcyclopentadieny)tin(II) with tungsten(cyclopentadienyl) (tricarbonyl) hydride

The nature of the product obtained from the title reaction has been reexamined, and identified as ClSn[W(CO)₃C₅H₅)]₃.     

Distortion of the coordination polyhedron in mononuclear copper(II) complexes. Optical absorption and electron spin resonance studies on some five-coordinate copper(II) complexes

The preparation and spectral properties are reported for a series of ten mixed-ligand copper(II) complexes of the form [Cu(A)(B)_n](X), where A is acetylacetonate anion, B represents a mono- or bidentate ligand such as morpholine, piperidine, isonicotinic acid hydrazide, 2,2′-bipyridine, 1,10-phenanthroline and X is variously NO^?₃ or ClO^?₄ anion and n = 1 or 2. The coordination of the anions and ligands has been demonstrated by infrared and electronic spectral methods. Electron spin resonance spectral data show the square-pyramidal five-coordinated arrangement around copper(II) in these complexes. Parameters such as g₆, g_⊥, A₆, A_⊥, 〈g〉 and 〈A〉 calculated from electron spin resonance data in solid and solution state at room temperature as well as frozen solution indicate the presence of the unpaired electron in the d_x2_?y2 or d_z2 orbital. These results are in good agreement with electronic and photoacoustic spectral studies.