铝镁混合金属氢氧化物溶胶阴离子交换性能研究

本文研究了电解质对铝镁混合金属氢氧化物（Ａｌ－ＭｇＭＭＨ）溶胶粒子中Ｃｌ－和ＯＨ－的阴离子交换性能。在所研究的电解质ＮａＮＯ３，ＨＣＯＯＮａ，ＣＨ３ＣＯＯＮａ，Ｎａ２ＣＯ３，Ｎａ２ＳＯ４和Ｎａ３ＰＯ４中，发现高价阴离子的交换能力大于低价阴离子的交换能力，无机阴离子的交换能力大于有机阴离子的交换能力。所研究Ａｌ－ＭｇＭＭＨ溶胶粒子的阴离子交换容量为２．８２ｍｍｏｌ／ｇ，比粘土粒子的阳离子交换容量大得多。     

激光烧蚀金属氯化物的发光光谱和飞行时间质谱研究

测定了３５５ｎｍ紫外线光烧蚀ＡｇＣｌ，ＣｕＣｌ和ＣｕＣｌ２产生的等离子体发光光谱顺３００～５００ｎｍ范围内的发光谱线可归属为激光态金属原子的发射线，飞行时间质谱测定表明激光烧蚀产生的正，负离子主要有Ａｇ，Ｃｕ，Ｃｕ２Ｃｌ＾＋，Ｃｕ２Ｃｌ２＾＋，Ｃｕ３Ｃｌ２及Ｃｌ，ＡｇＣｌ，ＡｇＣｌ２，Ａｇ２Ｃｌ３，ＣｕＣｌ，ＣｕＣｌ２，Ｃｕ２Ｃｌ３等，对激光烧蚀机理也进行了讨论。     

聚乙烯醇存在下以硝酸铁代替铁铵矾用Volhard法测定银和氯离子

１引言Ｖｏｌｈａｒｄ法以铁铵矾作指示剂，终点不够敏锐。尤其是直接滴定Ａｇ＋时，ＡｇＳＣＮ沉淀易吸附Ａｇ＋而导致终点提前；返滴定Ｃｌ－时ＡｇＣｌ沉淀易转化为ＡｇＳＣＮ，使终点颜色闪而褪去难于观察，分析结果偏低。虽用有机溶剂（如硝基苯）可促进ＡｇＣｌ沉淀凝聚与溶剂化而减缓ＡｇＣｌ的转化，但有机溶剂多数有毒使测定条件恶化．作者提出以聚乙烯醇（ＰＶＡ）化学修饰ＡｇＳＣＮ、ＡｇＣｌ沉淀的结构，阻止ＡｇＳＣＮ对Ａｇ＋的吸附与ＡｇＣｌ的转化，用硝酸铁代替铁铵矾指示滴定终点测定Ａｇ＋、Ｃｌ－的方法。本法比经典Ｖ…     

ICP—AES间接法连续测定混合物中的氯和碘离子的研究

本文研究了在Ｃｌ和Ｉ＾－的混合物中，加入过量Ａｇ＾＋使Ｃｌ＾－和Ｉ＾－分别以ＡｇＣｌ和ＡｇＩ沉淀后，用ＩＣＰ－ＡＥＳ测定剩余的Ａｇ＾＋，然后用ＮＨ３．Ｈ２Ｏ溶解ＡｇＣｌ沉淀，测定溶解液中的Ａｇ＾＋，间接得到Ｃｌ＾－的含量，以差减法求得Ｉ＾－量，实现Ｃｌ＾－和Ｉ＾＿的间接法连续测定。本文探讨了有关的化学条件和光谱测定条件，对方法的适用性进行了考察－共存离子的干扰情况，方法的精密度，检出限和试样中加入     

Ag－phen－TPPS_4体系光度法间接测定硫离子的研究－（Ⅱ）

本文报道了Ａｇ—ｐｈｅｎ─ＴＰＰＳ４光度法间接测定硫离子的新方法。疏离子的测定范围为０～０．１４μｇ／ｍＬ，摩尔吸光系数ε４３８＝５．２×１０５Ｌ·ｍｏｌ－ｌ·ｃｍ－１。用吹气法分离环境样品中的硫离子，以三乙醇胺的氢氧化钠溶液作吸收液，测定结果与亚甲基蓝标准法一致。     

3－氨甲基吡啶树脂的合成及五种氨基吡啶树脂对金铂吸附性的比较

研究了反应物配料比３－ＡＭＰ／Ｃｌ（摩尔比）、反应温度与时间对大孔型３－氨甲基吡啶树脂（３—ＡＭＰＲ）性能的影响规律．在最佳合成工艺条件下制得３－ＡＭＰＲ的功能基含量为３．１６ｍｍｏｌ／ｇ树脂．３－ＡＭＰＲ对ＡｕＣｌ６（２－），ＰｔＣｌ６（２－），ＩｒＣｌ６（２－），ＰｄＣｌ４（２－），ＲｈＣｌ６（３－）的吸附容量分别为８００．８，３８７．８，３８６．３，１３３．０，１０５．５ｍｇ金属／ｇ树脂；配位比分别为１．２９，０．６３，０．６４，０．４０，０．３３。比较了３—ＡＭＰＲ、２－ＡＭＰＲ、４－氨基吡啶树脂（４－ＡＰＫ）、３—ＡＰＲ、２－ＡＰＲ五种树脂对ＡｕＣｌ４－、ＰｔＣｌ６（２－）的吸附性，其中３－ＡＭＰＲ为最佳。     

ICP－AES间接法连续测定混合物中的氯和碘离子的研究

本文研究了在Ｃｌ￣－和Ｉ￣－的混合物中，加入过量Ａｇ￣＋使Ｃｌ￣－和Ｉ￣－分别以ＡｇＣｌ和ＡｇＩ沉淀后，用ＩＣＰ－ＡＥＳ测定剩余的Ａｇ￣＋，然后用ＮＨ＿３·Ｈ＿２Ｏ溶解ＡｇＣｌ沉淀，测定溶解液中的Ａｇ￣＋，间接得到Ｃｌ￣－的含量，以差减法求得Ｉ￣－量，实现Ｃｌ￣－和Ｉ￣－的间接法连续测定。本文探讨了有关的化学条件和光谱测定条件，对方法的适用性进行了考察──共存离子的干扰情况，方法的精密度、检出限和试样中加入回收试验。回收率为９７．１％～１０１．２％（Ｃｌ￣－），９８．１％～１００．４％（Ｉ￣－）。     

不同金属离子对CO／Al_2O_3中Co的分布和CoMoK／Al_2O_3催化

在γ－Ａｌ２Ｏ３中加入Ｚｎ２＋，Ｍｇ２＋，Ｃｕ２＋或Ｃｒ３＋后用漫反射光谱法研究了它们对随后加人的Ｃｏ分布的影响，同时还研究了这些离子对水煤气变换反应催化剂ＣｏＭｏＫ／Ａｌ２Ｏ３的催化活性的影响．发现Ｚｎ２＋，Ｍｇ２＋具有阻止Ｃｏ进入载体内层的作用，Ｃｕ２＋，Ｃｒ３＋的作用则相反．四面体配位倾向强的金属离子能阻止Ｃｏ进入载体内层，从而促进水煤气变换反应的催化活性，而八面体配位倾向强的金属离子的效果刚好相反．在６５０℃下，１００ｇＡｌ２Ｏ３含７ｇＭｇＯ时，Ｍｇ能最大限度地阻止Ｃｏ向Ａｌ２Ｏ３内层扩散，从而提高了ＣｏＭｏｋ／Ａｌ２Ｏ３的催化活性．     

反胶束笼对纳米氯化银反应性能的微环境限定

研究了反胶束中直径为10～17nm的AgCl微粒与亚甲基蓝之间的作用，比较了阴离子型和非离子型表面活性剂组成的反胶束微环境的影响，讨论了亚甲基蓝在粒子上的吸附，二聚体形成和纳米AgCl粒子对亚甲基蓝荧光猝灭机制．     

聚丙烯酰胺存在下Mohr法直接滴定碘、银等离子和硫氰酸根

1引言　　　　经典莫尔法对于　０．０１　ｍｏｌ／Ｌ的Ｃｌ－滴定误差达十０．６％需要进行指示剂的空白校正．且因　Ａｇｌ、ＡｇＳＣＮ沉淀强烈吸附Ｉ－和ＳＣＮ－、Ａｇ２ＣｒＯ４。沉淀凝聚后再转化成ＡｇＣｌ极慢，故不适于直接滴定Ｉ－、ＳＣＮ－、Ａｇ－。作者以聚丙烯酰胺（ＰＡＭ）化学修饰ＡｇＸ（ｘ－＝Ｉ－、ＳＣＮ－、Ｂｒ－、Ｃｌ－）及Ａｇ２ＣｒＯ４沉淀的结构，减小Ａｇｘ对Ｘ－的吸附与促进Ａｇ２ＣｒＯ４的转化，用莫尔法直接测定Ｉ－、ＳＣＮ－、Ａｇ＋及不需空白校正能准确滴定　０．０１　ｍｏｌ／ＬＣｌ－未见报道…     

A Novel Photo‐Induced Electrochemical Biosensing Method Based on Fluorescent Labeled Molecular Beacon

A novel photo‐induced electrochemical biosensing method has been developed based on fluorescence quenching effect and electrochemical method. In this sensing strategy, the molecular beacon probes labeled with methylene blue were immobilized on the gold nanoparticles modified gold electrode surface firstly; then dopamine was assembled on the electrode surface through electrostatic interaction with gold nanoparticles. Under the continuous illumination, the fluorescence of the methylene blue was quenched by the gold nanoparticles before hybridization; after hybridization with the complementary DNA, methylene blue was far away from the gold nanoparticles and the fluorescence recovered, and then singlet oxygen was generated in the photosensitive reaction of methylene blue in the presence of dissolved oxygen. Singlet oxygen reacted with dopamine, which resulted in the reduction of concentration of the dopamine on the electrode surface. The current of the dopamine on the electrode was used for the sensing of the conformational change of molecular beacon and hence for the detection of target DNA.     

Reduction of methylene blue by thiocyanate: kinetic and thermodynamic aspects

This article reports the reduction of methylene blue (MB) by thiocyanate ions (SCN(-)) in aqueous and micellar solutions. Thiocyanate ions are found to be an effective reducing agent for the decolorization of methylene blue under ambient condition. Effects of salting-in and salting-out agents have been investigated for real-time application in the reduction process. The salting-in agent urea has been found to uniquely enhance the rate of the reduction of MB by thiocyanate ion in the presence of micelles. Again, the catalytic activity of nanoparticles in the reduction of MB has also been studied. Detailed kinetic and thermodynamic aspects have been considered to realize the interaction between methylene blue and thiocyanate. Kinetic studies revealed that the reaction is reversible and follows first-order reaction kinetics.     

Photocatalytic performance of nano-ZnTiO3 decorated with Ag/AgCl nanoparticles for degradation of the organic dyes

Research on Chemical Intermediates - Ag/AgCl/ZnTiO3 nanohybrids were assembled by the photoreduction–precipitation assisted with ultrasonic method. Rhodamine B (RhB), methylene blue (MB) and...     

不同表面活性剂反胶束对纳米AgCl性能的影响

在反胶束中研究了直径10～14nm的AgCl微粒子与曙红间的作用,比较了阴离子型和非离子型表面活性剂组成的反胶束微环境效应.考察了AgCl粒子对曙红吸收光谱、荧光光谱及荧光寿命的影响.讨论了AgCl粒子对曙红荧光猝灭的机制,初步研究了稳定剂苯基巯基四氮唑及四氮茚对曙红-AgCl粒子反胶束体系的影响.     

Silica-coated gold nanostars for combined surface-enhanced Raman scattering (SERS) detection and singlet-oxygen generation: a potential nanoplatform for theranostics

This paper reports the synthesis and characterization of surface-enhanced Raman scattering (SERS) label-tagged gold nanostars, coated with a silica shell containing methylene blue photosensitizing drug for singlet-oxygen generation. To our knowledge, this is the first report of nanocomposites possessing a combined capability for SERS detection and singlet-oxygen generation for photodynamic therapy. The gold nanostars were tuned for maximal absorption in the near-infrared (NIR) spectral region and tagged with a NIR dye for surface-enhanced resonance Raman scattering (SERRS). Silica coating was used to encapsulate the photosensitizer methylene blue in a shell around the nanoparticles. Upon 785 nm excitation, SERS from the Raman dye is observed, while excitation at 633 nm shows fluorescence from methylene blue. Methylene-blue-encapsulated nanoparticles show a significant increase in singlet-oxygen generation as compared to nanoparticles synthesized without methylene blue. This increased singlet-oxygen generation shows a cytotoxic effect on BT549 breast cancer cells upon laser irradiation. The combination of SERS detection (diagnostic) and singlet-oxygen generation (therapeutic) into a single platform provides a potential theranostic agent.     

铜/石墨烯复合材料的制备及催化性能

采用水热法制备铜/石墨烯(Cu/RGO)复合材料,通过XRD、FTIR、SEM和TEM对材料的结构和形貌进行表征,并考察了复合材料在H₂O₂辅助作用下对次甲基蓝(MB)的催化作用。结果表明,该复合材料中石墨烯所负载的铜颗粒尺寸较小且分布均一,对MB的催化效果良好,0.18 g·L^-1复合催化剂在300 min内对MB的脱色效果可达90.7%,经过5次循环仍有88.0%以上。     

Cu(II) catalyzed oxidation of mercaptoacetic acid by methylene blue in acidic medium: Influence of solvent and morphology

Kinetic studies on the Cu(II) catalyzed oxidation of mercaptoacetic acid (thioglycolic acid, TGA) by the model electron receptor methylene blue in acidic medium show that the reaction follows a second order kinetics in TGA. The order in methylene blue is unity but at higher [TGA], the order is 3/4. The rate shows an inverse relationship with [H⁺] and a second order dependence on [Cu(II)]. The reaction conforms to Arrhenius behavior in aqueous medium but resorts to anti-Arrhenius behavior in aqueous methanol and in aqueous acetone media. The reaction involves the in situ participation of nanoparticles which has been confirmed by SEM, XRD, and FTIR techniques. In aqueous medium, cauliflower shaped nanoparticles (44.21–74.33 nm) are obtained but in the presence of acetone and methanol, nanogranules (38.96–70.73 nm) and nanodisks (47.30–72.16 nm), respectively, are produced at 35°C as revealed by SEM images and XRD data. The reaction is characterized by the participation of two transition states in aqueous acetone medium and the kinetics of the reaction, especially the temperature dependence, is governed by the adsorption of methylene blue on copper nanoparticles as influenced by morphology inter alia dielectric constant of the reaction medium.     

Facile and green solvothermal synthesis of palladium nanoparticle-nanodiamond-graphene oxide material with improved bifunctional catalytic properties

We developed a selective solvothermal synthesis of palladium nanoparticles on nanodiamond (ND)–graphene oxide (GO) hybrid material in solution. After the GO and ND materials have been added in PdCl₂ solution, the spontaneous redox reaction between the ND–GO and PdCl₂ led to the creation of nanohybrid Pd@ND@GO material. The resulting Pd@ND@GO material was characterized by X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared (FTIR) spectrometry, scanning electronic microscopy (SEM), and atomic absorption spectrometry methods. The Pd@ND@GO material has been used for the first time as a catalyst for the reduction for 2-nitrophenol and the degradation of methylene blue in the presence of NaBH₄. GO plays the role of 2D support material for Pd nanoparticles, while NDs act as a nanospacer for partly preventing the re-stacking of the GO. The Pd@ND@GO material can lead to high catalytic activity for the reduction reaction of 2-nitrophenol and degradation of methylene blue with 100% conversion within ~15 s for these two reactions even when the content of Pd in it is as low as 4.6 wt%.     

Synthesis and characterization of TiO<Subscript>2</Subscript>-montmorillonite nanocomposites and their photocatalytic activity

TiO₂ nanoparticles have been synthesized on the surface of exfoliated montmorillonite at a low temperature in benzyl alcohol medium. According to X-ray diffraction (XRD), N₂ adsorption-desorption isotherm and transmisson electron microscopy (TEM), it was found that the intercalation of TiO₂ nanoparticles destroyed the ordered structure of montmorillonite to some extent, and the crystallites of the nanocomposites are assembled to form a house-of-cards structure. The size of the nanoparticles in the interlamellar space is about 4 nm. The nanocomposites exhibited excellent photocatalytic activity in methylene blue degradation due to the synergetic effect of the adsorptive ability to organic compound of cetyl trimethylammonium bromide—montmorillonite and the catalytic ability of TiO₂ nanoparticles in it.