FID/TCD并联气相色谱法测定天然气水合物的气体组成

建立了一种氢火焰离子化检测器（FID）与热导检测器（TCD）并联检测的气相色谱分析技术。该方法一次进样,即可实现天然气水合物中C1~C6、CO2、H2S、O2+N2 16种气体成分的同时测定。实验优化了色谱柱、升温程序、柱流速、进样口温度、检测器温度、TCD参考气和尾吹气流速等仪器分析参数。在优化条件下,16种气体分子在实验浓度范围内线性关系良好,r2为0.999 03~0.999 98,方法检出限为0.000 3~0.046 mol/mol,相对标准偏差（n=6）为1.6%~5.0%。对祁连山冻土区、南海神狐海域、人工合成水合物样品的分析表明,该方法简便实用、灵敏可靠,可满足天然气水合物气体组成的分析要求。     

Enhancing Specific Binding of L929 Fibroblasts: Effects of Multi‐Scale Topography of GRGDY Peptide Modified Surfaces

Surface chemical composition and roughness caused by micro/nano‐topographical structures are two predominant factors in determining cellular response. A series of gold nanoparticle layers (GNPLs) with increasing surface roughness are prepared by depositing gold nanoparticles onto planar gold films. Glycine‐arginine‐glycine‐aspartic acid‐tyrosine (GRGDY) peptide is then conjugated to the surface through poly[oligo(ethylene glycol) methacrylate] polymer brushes as spacers. The pristine micro/nano‐roughness structures significantly inhibit L929 cell growth. After modification with POEGMA‐GRGDY, however, the micro/nano‐structures greatly enhance L929 cell‐specific interactions while maintaining superior low‐fouling ability compared to planar gold.

     

基于最小二乘法的动态光谱补偿拟合提取

高信噪比的动态光谱(dynamic spectrum, DS)提取是实现高精度动态光谱血液成分无创检测的一个关键。为了进一步提高提取的精度和速度,从原理上分析了各单波长光电容积脉搏波(photoelectric plethysmography,PPG)的线性相似性,并基于此性质提出了补偿拟合法：首先按照PPG单周期采样点数进行滑动平均得到漂移基线进行补偿,除去基线漂移;其次用各波长对数PPG与全波长叠加平均模板PPG进行最小二乘拟合,提取一次项系数构成DS。利用拟合提取法对近红外和可见光波段各25组PPG数据样本进行DS提取实验验证,并将结果与单沿提取法进行平滑性指标的对比,结果表明：近红外和可见光波段补偿拟合法获取DS的平均方差分别为单沿提取法的77.9%和59.5%,稳定提高了DS的平滑性;近红外和可见光波段补偿拟合法处理时间分别可以达到单沿提取法的10%和20%,处理速度得到显著改善。补偿拟合法在单沿提取法的基础上稳定提高了DS的信噪比,改善了DS提取质量,缩减了提取时间,并简化了处理步骤,有望推动DS无创血液成分检测的发展。     

快速气相色谱法分析白酒中的香味组分

中国的传统白酒里含有多种香味组分,包括醇类、醛类、酸类和酯类,它们的比率决定着白酒的香型和品质。这些组分可以使用气相色谱仪进行很好的分析并定性和定量。为了缩短分析时间,建立了一种快速检测白酒中香味组分的气相色谱法。采用该方法,用20 m×0.1 mm×0.1 μm的熔融石英毛细管柱在12 min之内完成了对白酒中香味组分的分析,分析时间只是传统色谱方法的三分之一。该方法的重现性良好。     

低温CO氧化中担载C0304催化剂失活的影响因素

This study focused on the influences of a variety of reaction parameters and guest molecules such as H2O and C3H8 on the deactivation of supported Co3O4 catalysts for CO oxidation.Additionally,the physical features of and carbon deposition on some samples after the reaction under the chosen conditions were determined by BET and X-ray diffraction as well as by carbon analyses to deduce the precursors associated with catalyst deactivation.Activity maintenance profiles of the catalysts for CO oxidation at 100°...     

Microscopic studies on imperfections in selected YAB single crystals

The as‐grown surface and inner structures of undoped and Nd³⁺‐, Cr³⁺‐, V³⁺‐, Ce³⁺‐, Er³⁺ and Yb³⁺ – and (Er³⁺ + Yb³⁺) – doped yttrium aluminum borate (YAB) single crystals grown from (K₂Mo₃O₁₀ + B₂O₃) flux by spontaneous crystallization or top seeded solution growth (TSSG) technique, were investigated using optical and scanning electron microscopic and analytic chemical methods. Fine and rough growth hillocks of dislocational origin, growth layers, traces of inner planar defects and foreign phase crystalline debris were found and analyzed on the as‐grown faces of crystals. Irregular grains and regular block structures and foreign phase inclusions were observed and studied in the interior of the crystals. The chemical compositions measured by energy dispersive X‐ray spectrometry on perfect and imperfect micro regions are compared with those obtained by flame atomic absorption spectrometry on bulk crystals. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

关于反共轭有序分拆的几个恒等式

In this paper, we first present several identities related to the inverse-conjugate compositions having parts of size ≤ 3, the compositions into parts equal to 1 or 2, the compositions into odd parts and the compositions into parts greater than 1. In addition, we provide a bijective proof of a relation for inverse-conjugate compositions having parts of size ≤ k.     

A Characterization of (2, n)-Semigroup of n-Place Functions and De Morgan (2, n)-Semigroup of n-Place Functions

In this article, by defining n Mann's compositions and one unary operation on the set of n-place functions over some set, we construct a De Morgan (2, n)-semigroup of n-place functions and so find an abstract characterization of this algebras.