Preparation of AgBiVMoO/-Al2O3 Catalysts for the Partial Oxidation of Propane

A novel mixed sol method was developed for the preparation of supported catalysts. Analyses by means of XRD and BET show that a 40%AgBiVMoO/γ-Al2O3 catalyst prepared by this method possessed high specific surface area and high dispersion of the active phase. As a result, high acrylic acid selectivity of 8.5% was obtained when the catalyst was used in the reaction of propane partial oxidation to acrylic acid in a fixed-bed reactor.     

高碘酸法测定水中锰的改进

介绍了一种室温下测定水中锰的方法，经检验，其显色反应可在短时间内完成，且色泽稳定，精密度和准确度均能达到分析要求。     

Trace anion determination in concentrated hydrofluoric acid solutions by two-dimensional ion chromatography I. Matrix elimination by ion-exclusion chromatography

Since years, ion exclusion chromatography (ICE) has been the standard method to separate strong acid analyte anions from concentrated weak acid matrices such as hydrofluoric acid (HF). In this work, the commercially available IonPac ICE-AS 1 column was used to separate trace levels of chloride, nitrate, sulfate and phosphate from HF solutions at 20% (w/w). The efficiency of the separation was studied in more detail using techniques such as ion chromatography (IC), inductively coupled plasma optical emission spectrometry (ICP-OES) and ICP-mass spectrometry (ICP-MS). For 20% (w/w) HF solutions and at a water carrier flow-rate of 0.50 ml/min, the cut window was set from 8.5 to 14.5 min. Under these conditions, analyte recoveries of better than 90% were obtained for chloride, nitrate and sulfate, but only about 75% for phosphate. The HF rejection efficiency was better than 99.9%. It was found that the ICP techniques, measuring total element levels and not species, yielded significantly higher recoveries for phosphorus and sulfur compared to IC. Evidence will be given that part of the added phosphorus (approximately 15% for an addition of 10 mg PO4/kg) is present as mono-fluorophosphoric acid (H2FPO3). In the case of sulfate, the difference between IC and ICP-MS could be attributed to an important matrix effect from the residual HF concentration.     

氧氟沙星荷移络合物的荧光特性和应用

研究了电子受体氯冉酸(CL)和2,3 二氰5,6 二氯1,4 对苯醌(DDQ)与电子给体氧氟沙星之间的荷移反应。实验发现,氧氟沙星与以上两种电子受体在氯仿中可生成稳定的n π络合物,其荧光强度较之氧氟沙星分别增强了22和54倍。据此建立了两种基于荷移反应简便可靠地测定氧氟沙星的荧光光谱新方法。CL法和DDQ法测定氧氟沙星的质量浓度分别为0 06～2.4μg/mL和0 16～2.0μg/mL时,荧光强度与质量浓度呈良好的线性关系。该方法已用于药物制剂中氧氟沙星的测定,其回收率分别为98.4%～100.9%和98.5%～100.4%。     

由二硫代肼基甲酸酯衍生的铜(Ⅱ)的希夫碱配合物的合成,结构和抑菌活性的研究

从S—苄基和S—甲基二硫代肼基甲酸酯衍生出的两种亚苄基丙酮希夫碱为配体,合成了铜(Ⅱ)配合物。经化学分析、磁性、红外、电子和EPR光谱的研究表明配合物有Cu(TSB)_2的形式,其中配体为双齿单价阴离子。在固态时,两种配合物分别为平面正方形和平面菱形结构。在溶液中,两者都为平面正方形。由EPR光谱分析得到的磁参数和键参数的值表明配合物中的键有较高的共价特征。对四种细菌的抑菌试验发现配体及其配合物均有抑菌活性,其中配合物的活性较高并研究了介质,pH对抑菌作用的影响。     

Lewis acid promoted reactions of γ,γ-dialkoxyallylic zirconium species with various carbonyl compounds

The reactions of γ,γ-dialkoxyallylic zirconium species with carbonyl compounds in the presence of Lewis acid are reported. The reactivity of γ,γ-dialkoxyallylic zirconium species and reaction pathway were strongly dependent on the structure and electrostatic nature of the carbonyl compounds.     

高效液相色谱法测定精对苯二甲酸中微量杂质

建立了高效液相色谱法（HPLC）同时测定精对-苯二甲酸（PTA）中微量杂质4-羧基苯甲醛（4-CBA）、对-甲基苯甲酸（P-TOL）和苯甲酸（C7H6O2）含量的方法。采用的色谱柱为Shim-PackWAX-1柱，流动相为0.1mol/L NH3H2PO4 6%CH3OH，(pH4.5)，检测波长为254nm。PTA中微量杂质4-CBA、P-TOL和C7H6O2的含量分别为0.59-235.20mg/kg、4.52-392.00mg/kg和0.28-24.55mg/kg时线性关系良好，其线性相关系数分别为0.9998、0.9997和0.9999。苯甲酸加样平均回收率99.03％，RSD0.37％。     

壳聚糖-聚羟基丁酸酯共混膜的制备与性质

以乙酸为共溶剂,制备了壳聚糖-聚羟基丁酸酯(CTS-PHB)共混膜,利用红外光谱(FT-IR)、广角X粉末衍射(WAXD)、扫描电镜(SEM)及差热分析(DTA)表征了共混膜的化学组成、晶形、形貌和热稳定性能。研究表明:CTS和PHB可在体积百分数为62.5%的乙酸溶液中共混,形成表面光滑、不透明的膜,干态共混膜具备一定的力学强度。各比例的CTS-PHB共混膜有相同的热分解温度,共混膜的形貌特征随两组分质量配比变化,其中mPHB/mCTS=1/1的共混膜显示出良好的有序结构。     

PAA/PVA SIPN高吸水性树脂的制备及性能研究

采用水溶液法合成了聚丙烯酸-聚乙烯醇(PAA-PVA)半互传网络型高吸水性树脂,其工艺条件的优化结果为:丙烯酸(AA)与PVA质量比为10∶0.5,AA中和度为80%,加入AA单体质量0.14%的引发剂和0.025%的交联剂,产物吸水率为530g/g,吸盐水率达63g/g。并采用红外光谱法表征了半互穿网络结构的形成。     

8-羟基喹啉-5-磺酸纤维微柱分离富集电感耦合等离子体原子发射光谱法同时测定多种痕量元素

本文合成了8-羟基喹啉-5-磺酸纤维滤纸片,以此做为微柱填充物同时富集了10种痕量元素,并分离了样品中的高盐组分.本方法可使痕量组分的分离与富集同步进行,因而特别适用于原子光谱测定前样品的预处理.