耐温阳离子树脂催化二壬基酚与苯酚合成壬基酚

用耐高温阳离子树脂催化二壬基酚与苯酚烷基转移为壬基酚．研究表明，经过耐温处理的强酸性阳离子交换树脂有较好的催化性能，当以CH2O2型树脂作为催化剂。在140℃，苯酚与二壬基酚摩尔比8：l的务件下反应2．5h，二壬基酚的转化率可以达到90％以上，适当延长反应时间。二壬基酚的转化率可以进一步提高，催化剂重复使用8次催化活性没有明显降低．     

正相高效液相色谱法分离检测壬基酚和短链壬基酚聚氧乙烯醚

建立了一种以正相高效液相色谱等强度洗脱分离检测壬基酚和短链壬基酚聚氧乙烯醚的新方法。采用Cosmosil5SL-Ⅱ(250mm×4.6mmi.d,5μm)色谱柱,以乙酸乙酯-乙醇为流动相,流速1.0mL/min,281nmUV检测,在10min内可分离检测p-壬基酚以及短链壬基酚聚氧乙烯醚混合物的3种主要组分。运用本方法对NP,NPnEO(n=1~3)进行测定的相对标准偏差分别为1.4%、1.6%、2.5%和1.4%;检出限分别为0.1mg/L(NP)和0.5mg/L(NPnEO),重复性好且灵敏度高。     

预衍生化-共振散射光谱法测定4-壬基酚

通过衍生反应,建立了用共振散射光谱法测定4-壬基酚的方法.在碳酸钠介质中,痕量4-壬基酚与丹酰氯反应,产物在300～600 nm波长范围有很强的共振散射光.在选定的测定波长396.8 nm处,共振光散射强度的改变值与4-壬基酚质量浓度在6.20×10-4～6.00×10-2mg·L-1范围内呈线性关系.方法检出限为0.20μg·L-1.结合C18柱固相萃取分离,应用于环境水样和合成水样中4-壬基酚的测定,样品加标回收率为91.25%～94.50%,相对标准偏差小于4.0%.     

柱前衍生-气相色谱/质谱法测定壬基酚方法研究

研究了一种利用壬基酚与N,O-双（三甲基硅烷基）三氟乙酰胺（简称BSTFA）柱前衍生气相色谱／质谱法测定污水中壬基酚的分析方法。通过实验确定了最佳的前处理方法,对比衍生和未衍生两种方法,确认该衍生化方法对11种常见壬基酚同分异构体具有更好的分离度（可将11种常见壬基酚同分异构体完全分离）,更高的灵敏度。方法检出限为0．55ng／L（以4-N—nonylphenol为标准,信噪比为3时的信号对应4-N—NP的浓度）。本方法能延长分离柱的使用寿命,是一个高重现性和高精密度测定壬基酚的方法。     

壬基酚聚氧乙烯醚聚合度对水煤浆浆体性质的影响

研究了壬基酚聚氧乙烯醚型添加剂的聚合度对变质程度不同的8种煤所制得的水煤浆浆体性质的影响规律。结果表明，壬基酚聚氧乙烯醚添加剂的聚合度对于8种煤所制得的水煤浆的成浆性、流变性以及静态稳定性均有一定的影响，存在一最佳范围。研究还发现，用壬基酚聚氧乙烯醚型添加剂制备水煤浆时，该添加剂的作用与煤的分析基水分质量分数、丝质组分质量分数以及孔体积之间存在着相关性。     

液相色谱-电喷雾质谱法同时测定水体中的壬基酚聚氧乙烯醚及其代谢产物

利用液相色谱-电喷雾质谱法同时分析水体中的壬基酚聚氧乙烯醚(NPEOs)及其代谢产物壬基酚聚氧乙烯醚乙酸(NPECs)和壬基酚(NP),用Waters Symmetry ShieldTMRP 18色谱柱,甲醇和乙酸铵溶液作为梯度洗脱的流动相,结果表明3类物质的分离效果良好,并可通过选择离子记录(SIR)模式实现NPEOs和NPECs各单体的定量。仪器的检出限为1~50 pg,选用Oasis HLB小柱进行固相萃取,回收率达75%~98%,平均标准偏差小于12%。该方法用于污水处理厂的水样测定,所取各水样中都测出了NP和NPEOs,并从氧化沟上清液中检测到NPECs。     

柱前衍生/气相色谱-质谱法同时测定水中壬基酚和邻苯二甲酸酯

在采用OasisHLB固相萃取柱富集水中壬基酚和邻苯二甲酸酯的基础上 ,利用壬基酚与N,O_双 (三甲基硅烷基 )三氟乙酰胺 (BSTFA)之间的衍生化反应 ,发展了气相色谱 -质谱同时测定水中壬基酚和邻苯二甲酸酯类化合物的方法 ,能够准确测定11种壬基酚同分异构体及4种邻苯二甲酸酯 ,回收率达到78.9 %±24.5 % ;具有较高的灵敏度 ,方法检出限达到(1.9～5.5)×10-4μg/L;并且具有很好的重现性和精密度。该方法已成功应用于城市污水中壬基酚和邻苯二甲酸酯类内分泌干扰物的分析测定     

TiO2/H2O2/超声波协同降解壬基酚聚氧乙烯醚溶液

采用经过处理的锐钛矿型TiO2作为催化剂,在H2O2存在下,以TiO2/H2O2/超声波协同降解壬基酚聚氧乙烯醚反应为模型,探讨了TiO2催化剂用量、H2O2用量、超声波功率、壬基酚聚氧乙烯醚溶液初始浓度、初始pH值对壬基酚聚氧乙烯醚降解率的影响。结果表明,在一定的超声波功率和一定的TiO2用量范围内,壬基酚聚氧乙烯醚降解率随超声波功率和TiO2用量的增大而增大,达到一定值后保持平稳;当H2O2浓度介于一定范围内,增大H2O2用量可提高壬基酚聚氧乙烯醚的降解率,但H2O2用量过多时,反而会使壬基酚聚氧乙烯醚的降解率下降;pH<5时,壬基酚聚氧乙烯醚降解效果较好,且pH值越小,降解率越高;pH>5时,降解率越来越低。TiO2/H2O2/超声波体系降解壬基酚聚氧乙烯醚产生了较强烈的协同效应,在同一时刻三者协同体系的降解率比其3种单独体系的降解率之和高出约60%;在TiO2催化剂用量0.4g/L、H2O2用量0.2g/L、超声波功率600W、降解时间120min的条件下,对初始质量浓度为80mg/L,pH=1的壬基酚聚氧乙烯醚溶液进行降解,其降解率达98%以上。     

壬基酚甜菜碱两性表面活性剂的合成和抗温耐盐性能

以壬基酚、环氧氯丙烷、二甲胺和3-氯-2-羟基丙磺酸钠为原料, 在催化剂的作用下经醚化、叔胺化、季铵化, 合成了壬基酚甜菜碱两性表面活性剂(NSZ), 并确定了最佳的反应条件。 壬基酚氯醇醚的最佳合成条件:物料比n(壬基酚):n(环氧氯丙烷)=1:4, 催化剂四丁基溴化铵用量为壬基酚用量的4%(摩尔比), 反应时间为4 h, 反应温度为95 ℃。 壬基酚叔胺的最佳合成条件:物料比为n(壬基酚氯醇醚):n(二甲胺):n(氢氧化钠)=1:2.5:1.1, 反应时间为4 h, 反应温度为60 ℃。 NSZ的最佳合成条件:以异丙醇/水为溶剂且其体积比为2:1, 反应温度为85 ℃, 反应时间24 h, n(3-氯-2羟基丙磺酸钠):n(壬基酚叔胺)=1.2:1, 反应体系的pH值为8~9。 通过测定NSZ在高温高矿化度条件下的界面性能、乳化性能和热稳定性, 证明了NSZ具有良好的耐温抗盐性能。     

环境样品中壬基酚及相关化合物的分离富集与测定

对近 2 0年来环境样品中壬基酚及其相关化合物分析方法的研究进展进行了综合评述 ,重点讨论了样品前处理方法、柱分离和测定技术     

Contributions to the Chemistry of the Binary Compounds of the Transition Elements

Phase and structural relationships of the sulfur, selenium, and tellurium compounds of the 4d and 5d transition elements of groups IV to VII of the periodic system are discussed. Homologous elements behave very similarly with respect to the chalcogens, and this is particularly the case for niobium and tantalum, and for molybdenum and tungsten. However, zirconium, niobium, and molybdenum have a greater tendency towards formation of chalcogen-poor phases than their homologues hafnium, tantalum, and tungsten. Subchalcogenides are known only for zirconium and niobium. The number of phases and the tendency towards formation of solid solutions are considerably smaller among the tellurides than among the sulfides and selenides. The crystal structures of the telluride phases also differ from those of the sulfide and selenide phases of analogous composition. In addition, a review of the phase and structural relationships of the arsenic and antimony compounds of the 4d and 5d transition elements of groups V to VII is given.     

Semiconductor quantum dots and metal nanoparticles: syntheses,optical properties,and biological applications

We review the syntheses, optical properties, and biological applications of cadmium selenide (CdSe) and cadmium selenide–zinc sulfide (CdSe–ZnS) quantum dots (QDs) and gold (Au) and silver (Ag) nanoparticles (NPs). Specifically, we selected the syntheses of QDs and Au and Ag NPs in aqueous and organic phases, size- and shape-dependent photoluminescence (PL) of QDs and plasmon of metal NPs, and their bioimaging applications. The PL properties of QDs are discussed with reference to their band gap structure and various electronic transitions, relations of PL and photoactivated PL with surface defects, and blinking of single QDs. Optical properties of Ag and Au NPs are discussed with reference to their size- and shape-dependent surface plasmon bands, electron dynamics and relaxation, and surface-enhanced Raman scattering (SERS). The bioimaging applications are discussed with reference to in vitro and in vivo imaging of live cells, and in vivo imaging of cancers, tumor vasculature, and lymph nodes. Other aspects of the review are in vivo deep tissue imaging, multiphoton excitation, NIR fluorescence and SERS imaging, and toxic effects of NPs and their clearance from the body. Figure Semiconductor quantum dots and metal nanoparticles have extensive applications, e.g., in vitro and in vivo bioimaging Tamitake Itoh and Abdulaziz Anas contributed equally to this article.     

正丁胺对激光染料荧光谱影响的研究

用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.     

Simultaneous analysis of serotonin, melatonin, piceid and resveratrol in fruits using liquid chromatography tandem mass spectrometry

An analytical method was developed for the simultaneous quantification of serotonin, melatonin, trans- and cis-piceid, and trans- and cis-resveratrol using reversed-phase high performance liquid chromatography coupled to mass spectrometry (HPLC-MS) with electrospray ionization (ESI) in both positive and negative ionization modes. HPLC optimal analytical separation was achieved using a mixture of acetonitrile and water with 0.1% formic acid as the mobile phase in linear gradient elution. The mass spectrometry parameters were optimized for reliable quantification and the enhanced selectivity and sensitivity selected reaction monitoring mode (SRM) was applied. For extraction, the direct analysis of initial methanol extracts was compared with further ethyl acetate extraction. In order to demonstrate the applicability of this analytical method, serotonin, melatonin, trans- and cis-piceid, and trans- and cis-resveratrol from 24 kinds of commonly consumed fruits were quantified. The highest serotonin content was found in plantain, while orange bell peppers had the highest melatonin content. Grape samples possessed higher trans- and cis-piceid, and trans- and cis-resveratrol contents than the other fruits. The results indicate that the combination of HPLC-MS detection and simple sample preparation allows the rapid and accurate quantification of serotonin, melatonin, trans- and cis-piceid, and trans- and cis-resveratrol in fruits.     

THE EFFECT OF CLAY DISPERSION ON THE CRYSTALLIZATION AND MORPHOLOGY OF POLYPROPYLENE／CLAY COMPOSITES

PP/clay composites with different dispersions, namely, exfoliated dispersion, intercalated dispersion and agglomerates and particle-like dispersion, were prepared by direct melt intercalation or compounding. The effect of clay dispersion on the crystallization and morphology of PP was investigated via PLM, SAXS and DSC. Experimental results show that exfoliated clay layers are much more efficient than intercalated clay and agglomerates of clay in serving as nucleation agent due to the nano-scale dispersion of clay, resulting in a dramatic decrease in crystal size (lamellar thickness and spherulites) and an increase of crystallization temperature and crystallization rate. On the other hand, a decrease of melting temperature and crystallinity was also observed in PP/clay composites with exfoliated dispersion, due to the strong interaction between PP and clay. Compared with exfoliated clay layers, the intercalated clay layers have a less important effect on the crystallization and crystal morphology. No effect is seen for samples with agglomerates and particle-like dispersion, in regard to melting temperature, crystallization temperature, crystal thickness and crystallinity.     

Fluorine in the Earth and the solar system,where does it come from and can it be found?

This review (1) presents a summary of the distribution of fluorine in different fluid (surficial, subterranean, metamorphic, and magmatic–hydrothermal–geothermal) and solid (oceanic and continental crust, mantle, and core) domains of the Earth, and various extraterrestrial materials and bodies (meteorites, planets and moons, and the Sun); (2) it provides an estimate of the total fluorine abundance for the Earth and in its dominant reservoirs contributing to the Earth's fluorine endowment; and (3) it discusses key observations that could further improve our understanding of fluorine abundances and geochemical systematics.     

ADSORPTION OF CHLOROFORM AND TRICHLOROETHYLENE IN WATER WITH A NEW KIND OF HYPERCROSSLINKED RESINS

In this paper two newly developed hypercrosslinked resins were used to treat micropolluted drinking water and their static and kinetic adsorption were investigated at 293 K. The results show that these two adsorbents are superior to Amberlite XAD-4 for removing chloroform and trichloroethylene in aqueous solutions. The breakthrough capacity and the total capacities from mini-column adsorption studies for chloroform and trichloroethylene on XAD-4, ZH-01 and ZH-00 are calculated respectively under experimental conditions     

生物热化学和热动力学研究进展

生命相关过程伴随着极其复杂的化学和物理过程,包含着物质变化和能量转换,其中部分能量不可避免地会以热的形式表现出来。用微量热技术和热动力学方法,研究复杂生命体系和相关反应的热动力学过程,可宏观地、本质地反映生命相关过程的内在规律。本文综述了生物量热学方法和技术在生命科学中的应用,介绍了生物量热技术在生态系统、生物组织和器官、细胞水平、亚细胞水平和分子层面等不同生物层次和结构水平上的研究现状和进展。     

蛋白质、凝胶电泳及其分析应用

蛋白质是重要的生物高分子，具有催化、传输、运动、防御和调节等重要生理功能，其分离、纯化和表征对理解和利用它们在生命过程中的作用具有重大理论意义和实际价值。凝胶电泳是蛋白质测定中应用最广泛和最强有力的工具。本文讨论凝胶电泳方法及其在蛋白质分析方面的新进展。首先介绍蛋白质的性质和功能，然后讨论蛋白质试样制备方法，最后评述各种凝胶电泳分离技术及其在蛋白质分离、纯化和表征等方面的应用。     

Residue‐centric modeling and design of saccharide and glycoconjugate structures

The RosettaCarbohydrate framework is a new tool for modeling a wide variety of saccharide and glycoconjugate structures. This report describes the development of the framework and highlights its applications. The framework integrates with established protocols within the Rosetta modeling and design suite, and it handles the vast complexity and variety of carbohydrate molecules, including branching and sugar modifications. To address challenges of sampling and scoring, RosettaCarbohydrate can sample glycosidic bonds, side‐chain conformations, and ring forms, and it utilizes a glycan‐specific term within its scoring function. Rosetta can work with standard PDB, GLYCAM, and GlycoWorkbench (.gws ) file formats. Saccharide residue‐specific chemical information is stored internally, permitting glycoengineering and design. Carbohydrate‐specific applications described herein include virtual glycosylation, loop‐modeling of carbohydrates, and docking of glyco‐ligands to antibodies. Benchmarking data are presented and compared to other studies, demonstrating Rosetta's ability to predict glyco‐ligand binding. The framework expands the tools available to glycoscientists and engineers. © 2016 Wiley Periodicals, Inc.