Determination of Estrogenic Nonylphenol and Bisphenol a in River Water by Solid‐Phase Extraction and Gas Chromatography‐Mass Spectrometry

A simple and sensitive method is presented for the analysis of nonylphenol (NP) and bisphenol A (BPA), two well known hormonally active agents (HAAs), in the samples of river water. The method involves extraction of the sample by a graphitized carbon black (GCB) solid‐phase extraction, and determination by an ion‐trap gas chromatography‐mass spectrometry (GC‐MS). The large‐volume injection technique provides high precision and sensitivity for NP and BPA, to quantitation at < 0.05 μg/L in 200 mL of water samples. Recovery of NP and BPA in spiked water samples ranged from 80% to 85%. Relative standard deviations (RSD) of replicate analyses ranged from 1.6% to 6.9%. The concentrations of NP in rivers were in the range between 0.4 to 2.4 μg/L, which were below the threshold concentration (10 μg/L) for vitellogenin induction in fish, but 78%) of water samples from five rivers exceeded the predicted‐no‐effect concentration (PNEC) of 0.7 μg/L as proposed recently. The concentrations of BPA ranged from < 0.05 μg/L to 3.0 μg/L, which all were below the PNEC of 64 μg/L.     

X-ray spectrometry using polycapillary X-ray optics and position sensitive detector

Polycapillary X-ray optics (capillary X-ray lens) are now popular in X-ray fluorescence (XRF) analysis. Such an X-ray lens can collect X-rays emitted from an X-ray source in a large solid angle and form a very intense X-ray microbeam which is very convenient for microbeam X-ray fluorescence (MXRF) analysis giving low minimum detection limits (MDLs) in energy dispersive X-ray fluorescence (EDXRF). A new method called position sensitive X-ray spectrometry (PSXS) which combines an X-ray lens used to form an intense XRF source and a position sensitive detector (PSD) used for wavelength dispersive spectrometry (WDS) measurement was developed recently in the X-ray Optics Laboratory of Institute of Low Energy Nuclear Physics (ILENP) at Beijing Normal University. Such a method can give high energy and spacial resolution and high detection efficiency simultaneously. A short view of development of both the EDXRF using a capillary X-ray lens and the new PSXS is given in this paper.     

〔phenH〕〔La(NO_3)_4(H_2O)(phen)〕·H_2O的合成和晶体结构

标题化合物由Ｌａ（ＮＯ３）３·ｎＨ２Ｏ,１,１０－邻菲罗啉（ｐｈｅｎ）和乙酰丙酮等在无水乙醇和水的混合溶剂中合成并用ＩＲ谱和Ｘ射线结构分析进行表征。晶体学数据如下：Ｃ２４ Ｈ２１ＬａＮ８Ｏ１４,Ｍｒ＝ ７８４．４０, 三斜, Ｐ１, ａ＝ ７．１２４（１）, ｂ＝ １１．０４７（２）, ｃ＝ １９．３９３（４）, α＝ ８１．１０（３）, β＝ ８７．７９（３）, γ＝ ７４．３６（３）°, Ｖ＝ １４５２．０（５）３, Ｚ＝ ２, Ｄｃ＝１．７９４ｇ／ｃｍ ３, Ｆ（０００）＝ ７８０, μ（ＭｏＫα）＝ １．５５７ｍ ｍ － １。化合物由阳离子〔ｐｈｅｎＨ〕＋ 和配合阴离子〔Ｌａ（ＮＯ３）４（Ｈ２Ｏ）（ｐｈｅｎ）〕－ 及一个结晶水分子组成。配合阴离子中以Ｌａ原子为中心,周围被２ 个Ｎ原子（来自ｐｈｅｎ）和９ 个Ｏ原子（来自ＮＯ３－ 和Ｈ２Ｏ）所占据,构成较为罕见的１１ 配位。晶胞中两两阳离子〔ｐｈｅｎＨ〕＋ 及两两配体ｐｈｅｎ 平面之间均相互平行堆积,并有多种类型的氢键存在,这些都可以降低能量,有利于化合物在晶体中的堆积。     

The Crystal structure of Hexakisammonium Diacetyloctamolybdate Tetrahydrate

1　ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｓｔｕｄｉｅｓｏｎｏｒｇａｎｉｃｐｏｌｙｏｘｏｍｅｔａｌｌａｔｅｓｈｅｌｐｔｏｕｎｄｅｒｓｔａｎｄｔｈｅｒｏｌｅｓｏｆｐｏｌｙｏｘ ｏｍｅｔａｌｌａｔｅｓｏｎｃａｔａｌｙｓｉｓ.Ａｓｅｒｉｅｓｏｆｏｃｔａｍｏｌｙｂｄａｔｅｓｗｉｔｈｄｅｓｃｒｉｐｔｉｏｎ〔Ｍｏ8Ｏ2 6Ｘ2 〕2ｎ -4(ｎｉｓｔｈｅｎｏｒｍａｌｃｈａｒｇｅｏｆｔｈｅｃｏｏｒｄｉｎａｔｅｄｂａｓｅＸ)ｈａｖｅｂｅｅｎｒｅｐｏｒｔｅｄｉｎｌｉｔｅｒａｔｕｒｅｓ .Ｔｈｅｉｒｓｔｒｕｃｔｕｒｅｓｏｆｔｈｅα ,β ,γ …     

西加毒素(CTX)的电子结构及构效关系研究

应用MNDO方法对CTX衍生物进行了量子化学计算 ,得到了它们的电子结构信息.根据构象分析研究了它们的空间结构.推测出它们的活性部位 ,探讨了与受体结合时的作用方式 ,讨论了结构 -活性关系 ,解释了活性差异的原因.研究结果表明该类化合物的D、E、F环和A环及其支链等部位的不饱和键对活性有重要影响     

A new mechanism of benzophenone photoreduction in photoinitiated crosslinking of polyethylene and its model compounds

The photolytic products and a new photoreduction mechanism of benzophenone (BP) as a photoinitiator in the photocrosslinking of polyethylene (PE) and its model compounds (MD) have been studied by means of fluorescence, ESR, ¹³C and ¹H NMR spectroscopy. The fluorescence spectra from the PE and MD systems demonstrate that the main photoreduction product of BP (PPB) is benzpinacol formed by the recombination of two diphenylhydroxymethyl (K^•) radical intermediates. The ESR spectrum obtained from the UV irradiation of the MD/BP system gives positive evidence of K^• radicals. Two new PPB products: an isomer of benzpinacol with quinoid structure, 1‐phenyl‐hydroxymethylene‐4‐diphenyl‐hydroxymethyl‐2,5‐cyclohexa‐diene and three kinds of α‐alkylbenzhydrols have been detected and identified for the first time by ¹³C and ¹H NMR spectroscopy from the MD systems. The latter could be formed by the reactions of K^• radicals with alkyl radicals produced by hydrogen abstraction of the excited triplet state ³(BP)* from polyethylene or its model compounds. These results provide new experimental evidence for elucidating the photoreduction mechanism of BP in the photoinitiated crosslinking of polyethylene. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 999–1005, 2000     

Synthesis of new 3'-, 5-, and N(4)-modified 2'-O-methylcytidine libraries on solid support

A versatile solid phase combinatorial approach was developed and utilized for the rapid synthesis of new 2'-O-methylcytidine nucleoside libraries 1-7 containing 672 compounds with 3'-deoxy-3'-C-methyl, 3'-deoxy-3'-C-hydroxymethyl, and 5-alkyl/alkynyl modifications. The modified uridine scaffolds 8-10, 23-25, and 31 were loaded onto the 4-methoxytrityl chloride (MMT-Cl) polystyrene resin through the hydroxyl groups at the 5'-position as well as on the substituents at the 3'- and 5-positions. The scaffolds loaded on the resin were orthogonally protected by MMT group on the resin itself and TBDMS or acetyl protecting groups. The 4-position of the uridine derivatives was activated by 2,4,6-triisopropyl benzene sulfonyl chloride for further derivatization. The resins 14-16, 28-30, and 32 loaded with the corresponding activated scaffolds were reacted with the selected and validated amino building blocks in the 96 well format on the semiautomated synthesizer. The high-quality 2'-O-methylcytidine libraries 1-7 were thus generated and characterized by liquid chromatography-mass spectrometry (LC-MS) analysis with 63-99% successful rates.     

PtBA-g-PPEGMEMA接枝共聚物的合成及其包埋阿霉素的研究

通过可逆加成-裂解链转移聚合和原子转移自由基聚合,制备了以聚丙烯酸叔丁酯为主链、以聚(聚乙二醇单甲醚甲基丙烯酸酯)为侧链的两亲性接枝共聚物PtBA-g-PPEGMEMA,该方法克服了以往通过聚合物修饰来引入接枝点时所存在的接枝点密度不高和不可控的局限性.接着,以PtBA-g-PPEGMEMA为载体,对抗肿瘤药物阿霉素进行了负载,制备得到了尺寸为164.8nm的纳米载药胶束.其释放试验表明,该体系具有缓释特征.     

生物光子晶体蝴蝶翅膀表面的凝结液滴憎水性

采用环境扫描电子显微镜(ESEM)观测了蝴蝶翅膀的微观结构, 揭示了蝴蝶翅膀颜色的各向异性特征. 采用高速摄像仪实时动态观察了蝴蝶翅膀的水凝结浸润特性, 分别探究了蝴蝶翅膀在水平、 不同倾斜角度以及在振动条件下的水凝结的憎水性. 基于微观结构, 对蝴蝶翅膀的水凝结憎水特性进行机理阐述. 定量描述了其表面的黏滞特性, 并基于蝴蝶翅膀的微观结构效应阐述了翅膀表面水凝结的憎水性机制.