肿瘤患者放疗前后血清八种微量元素含量的研究

对临床、病理、放射线或CT检查确诊的82名癌肿患者，在放疗前后和对42名健康人进行了微量元素铁、锌、铜、锰、硒，铬、钴、镍的分析。研究结果显示：1．癌肿患者血清铜、镍、锰、铬、钴的含量比健康人高，而血清锌、铁、硒的含量却比健康人低；2．血清Cu／Zn、Cr／Zn、Co／Zn、Ni／Zn的比值癌肿患者均比健康人高，而Fe、Zn、Se／Zn的比值却相反。因此，可根据血清铜升高、血清锌降低，血清铜／锌比值升高的特点。用于癌肿的早期诊断；3．癌肿患者放疔后血清铁、锌含量进一步下降，铜、锰、铬的含量也出现降低，唯有硒的含量有所上升。因此，放疗时应注意补充铁、锌、铜元素。     

The projection method for computing multidimensional absolutely continuous invariant measures

We present an algorithm for numerically computing an absolutely continuous invariant measure associated with a piecewiseC ² expanding mappingS: on a bounded region R ^N. The method is based on the Galerkin projection principle for solving an operator equation in a Banach space. With the help of the modern notion of functions of bounded variation in multidimension, we prove the convergence of the algorithm.     

Efficient degradation of organic pollutants mediated by immobilized iron tetrasulfophthalocyanine under visible light irradiation

Supported iron tetrasulfophthalocyanine can efficiently catalyze the degradation of organic pollutants by H2O2 under visible light irradiation in an aqueous solution, and the catalyst can be easily recycled without apparent loss of activity.     

A New Triterpenoid from "Gualou-xiebai-baijiu-tang" Consisting of Fructus trichosanthis and Bulbus allii mtacrostemi

A new triterpenoid saponin was isolated by bioactivity-guided isolation from "Gualou-xiebai-baijiu-tang" consisting ofFructus trichosanthisi and Bulbus allii macrostemi. Its structure was determined as 3-O-β-D-galactopyranosyl-hederagenin 28-O-β-D-xylopyranosyl (1→6)- β-D-galactopyranosyl ester by means of chemical evidences and spectral analysis.     

Which electron count rules are needed for four-center three-dimensional aromaticity?

A series of charged and neutral four-center n-electron (4c-ne, n = 1-4) molecules based on the adamantane framework, but which include combinations of boron, nitrogen, and phosphorus atoms at bridgehead positions, were studied computationally at the B3LYP/6-31G* level of density functional theory (DFT). The three-dimensional aromaticity, observed earlier for the 1,3,5,7-bisdehydroadamantane dication (1), is found to be general for 4c-2e electron systems. The degree of electron delocalization, evaluated by energetic, geometric, and various magnetic criteria, is quite independent of the molecular symmetry (point groups vary from Td to Cs), the degeneracy of the orbitals, the molecular charges, and the nature of the atoms participating in the delocalized bonding. Although the multiple positive (e.g., in 1 and some of the heteroatom systems) and multiple negative charges are strongly repulsive, the rigid adamantane frameworks help hold the bridgehead atoms within bonding distances with the fewer available electrons. The corresponding 4c-1e doublets are approximately half as aromatic as the 4c-2e singlets based on the same criteria. However, the three-electron systems may either adopt distorted but still four-center delocalized structures, or alternative 3c-2e two-dimensional arrangements in which the fourth bridgehead atom is more distant. There is no need to derive special rules for each point group for 4c-ne systems. Although the three-dimensional stabilization is computed to be quite appreciable, ranging between 10 and 50 kcalmol(-1), this delocalization energy is generally not sufficient to overcome distortion due to strain in higher homologues of 1 and in analogous noncage systems. Among the various 4c-2e homoadamantanedehydro dications studied, only the 1,8-dehydrohomoadamandiyl-3,6-dication forms a three-dimensional aromatic system.     

Identification of ochratoxin A in food samples by chemical derivatization and gas chromatography-mass spectrometry.

The contamination of foods with ochratoxin A can be determined very sensitively by high-performance liquid chromatography (HPLC) with fluorescence detection. A novel procedure is described to confirm OA-positive results quantitatively down to the HPLC detection limit of 0.1 ppb. For this, ochratoxin A in the sample extract is converted into its O-methylochratoxin A methyl ester derivative, which is identified subsequently by gas chromatography-mass spectrometry negative-ion chemical ionization and multiple ion detection modes using the hexadeuterated O-methyl-d3-ochratoxin A methyl-d3 ester derivative as internal standard for quantification. In the analysis of more than 60 contaminated samples, the procedure was found to be very accurate.     

Statistical radical copolymerization of styrene and methyl methacrylate in a room temperature ionic liquid

Use of a room temperature ionic liquid as the medium for conventional free radical copolymerization of styrene and methyl methacrylate resulted in reactivity ratios that were significantly different from those obtained in conventional organic solvents or in bulk, demonstrating that polymerization in this alternative medium offers potential to create copolymers having new monomer sequences.     

熔融织构生长强磁浮YBCO超导块材的取向和结构

采用熔融织构生长法结合顶部Ｓｍ１２３籽晶技术，成功地制备了直径为２０ｍｍ的ＹＢＣＯ超导块材。该块材具有极强的磁性能。用Ｘ射线θ／２θ扫描和Φ扫描分析其结构表明，样品在三维方向上具有很强的择优取向，其ｃ、ａ、ｂ轴方向分别与Ｓｍ１２３籽晶的ｃ、ａ、ｂ轴方向一致，并具有类似单晶的结构特点。