超细4A分子筛的超声波低温快速合成

在低温条件下用超声波快速合成了4A分子筛.产物分别用XRD,IR,SEM和DSC等进行了表征.结果表明,用超声波法合成4A分子筛的速度是常规法的24倍.合成产物的白度为95%,钙离子交换容量为335mgCaCO₃/g4A分子筛,平均粒径为280nm.与采用常规方法合成的产物相比,超声波法合成的产物热稳定性有所下降.     

磷酸镧在沸石分子筛上的分散及其催化性能

将LaPO4通过微波加热的方法分散在Y分子筛上制得了负载型分子筛催化剂．通过XRD，TPD，BET等方法对分子筛的结构和物性进行了表征．并将分子筛催化剂用于催化乙氧基化反应．研究结果表明，通过微波加热的方法，质量分数为20％的磷酸镧均匀地分散在分子筛的内外表面上，催化活性有了较大提高．当CaY—LaPO4催化剂的质量分数为5％，反应温度为150℃，反应压力0．3～0．4MPa，n(醇)：n(环氧乙烷)=1：1时，产品的收率达84％，产品中环氧乙烷加成数(EO)为1的占46％，产品的分子量分布指数Q=3999．     

具有MFI结构的La-Si ZSM-5分子筛的合成

首次合成了稀土元素掺杂的具有MFI结构的La-Si ZSM-5分子筛,并采用各种技术对所合成的分子筛进行了表征.XRD衍射表明所合成的微孔材料具有典型的MFI结构,N2吸脱附、FT-IR及SEM测试结果均表明镧原子进入了分子筛骨架.     

微波辐射磷钨酸催化合成乙酸丁酯

以磷钨酸作催化剂 ,4A分子筛为脱水剂 ,采用微波辐射技术 ,用乙酸和丁醇直接合成乙酸丁酯 .考察了催化剂用量、微波辐射功率、时间、乙酸丁醇比对反应转化率的影响 .最佳反应条件为 :乙酸与磷钨酸的物质的量的比为 1∶0 .0 0 16 6 4,微波辐射功率及时间为 335W ,15min ,乙酸丁醇的物质的量的比为 1∶1.5 .此条件下转化率为 96 % .     

微波法煅烧高岭土及合成洗涤助剂4A沸石

本文用微波法煅烧高岭土并合成4A沸石.与传统高温热处理法相比,微波法煅烧的高岭土其活化深度好,增白程度高,粒度细,能耗大为降低,显示了明显的优越性.本文还采用煅烧后的活性高岭土为原料,在微波辐射下进行4A沸石的合成,并用XRD、DTA、SEM、白度计、钙离子交换度等进行表征.与传统水热处理法相比,微波法所得样品在结晶度、白度和钙离子交换能力方面均显优势,且大大地加快了沸石晶化反应速率.经动力学处理,发现微波法合成4A沸石的晶核形成及晶体成长的表观活化能均有所下降,说明微波辐射能促进新相的形成,加快整个晶化反应速率.     

MCM—41介孔分子筛合成研究：Ⅱ.微波辐射合成法

采用微波辐射技术合成了ＭＣＭ－４１介孔分子筛,并用ＸＲＤ,ＳＥＭ,ＩＲ,ＮＭＲ和吸附等表征手段考察了其晶化过程,晶体形貌和稳定性等特点,结果表明,微波法合成ＭＣＭ－４１分子筛时诱导期极短,晶化速度很快且在晶化后期无转晶现象;微波法合成的ＭＣＭ－４１试样的吸附容量较低,但具有较强的耐热及水热稳定性和抗酸碱能力。     

W-MCM-48中孔分子筛的微波合成与表征

在微波辐射下快速合成出Ｗ－ＭＣＭ－４８分子筛,通过ＸＲＤ,ＦＴ－ＩＲ和Ｎ２吸附等手段对样品进行了表征,并考察了合成条件对Ｗ－ＭＣＭ－４８相对结晶度的影响。结果表明：在微波辐射下快速合成出的Ｗ－ＭＣＭ－４８分子筛结晶及热稳定性良好,且孔道规整;Ｗ离子进入了分子筛的骨架;以十六烷基三甲基溴化铵为模板剂,最佳合成条件为ｎ（Ｎａ２Ｏ）／ｎ（ＳｉＯ２）＝０．２５,ｐ＝０．４８ＭＰａ,ｔ＝２ｈ。苯乙烯催化氧化     

微波辐射下4A分子筛催化γ-内酰胺的合成及用粗糙集理论进行溶剂筛选

 采用微波辐射和分子筛催化相结合的方法合成了高光学活性的γ-内酰胺,并采用粗糙集理论进行了溶剂筛选. 结果表明,在微波辐射下,以4A分子筛为催化剂,二甲基亚砜为溶剂时,γ-氨基酸可直接环化生成γ-内酰胺,反应的化学收率高,消旋化产物少.     

铝镧修饰六方介孔分子筛的合成、表征及在乙氧基化反应中的催化性能

铝镧修饰六方介孔分子筛的合成、表征及在乙氧基化反应中的催化性能;介孔分子筛;盐酸;复合模板剂;乙氧基化反应     

膨润土碱熔活化合成4A分子筛的研究

以天然膨润土为原料,采用高温碱熔水热法合成4A分子筛。探讨了活化温度、SiO2/Al2O3、Na2O/SiO2、H2O/Na2O等工艺条件对4A分子筛结构与性能的影响。结果表明,最佳的活化温度为600℃;物料经此温度活化后,调节组成为SiO2/Al2O3=1.5、Na2O/SiO2=3与H2O/Na2O=50,于90℃反应6小时可以得到质量较好的4A分子筛,其产品的晶形规整,晶粒均小于2μm,钙离子交换容量可达到314mg CaCO3/g。     

UPLC-MS/MS detection of disaccharides derived from glycosaminoglycans as biomarkers of mucopolysaccharidoses

Mucopolysaccharidoses (MPSs) are a group of disorders resulting from primary defects in lysosomal enzymes involved in the degradation of glycosaminoglycans (GAGs). Depending on the specific enzyme defect, the catabolism of one or more GAGs is blocked leading to accumulation in tissues and biological fluids. GAG measurements are important for high-risk screening, diagnosis, monitoring treatment efficacy, and patient follow up. The dimethylmethylene blue (DMB) spectrophotometric method commonly used in most biochemical genetics laboratories relies on a non-specific total GAG analysis which has led to false positive results, and even false negative results (mainly for MPS III and IV patients). The main objective of our project was to devise and validate a reliable tandem mass spectrometry multiplex analysis for the urine quantitation of four GAGs (dermatan sulfate (DS), heparan sulfate (HS), keratan sulfate (KS), and chondroitin sulfate (CS)) for an eventual technological transfer to the clinic. The developed methodology is rapid (7 min) and our results showed good intraday and interday precision (RSDs ≤ 8.7%) and accuracy (Biases range: −12.0%–18.4%). Linearity was good (r² > 0.995) for DS, HS, CS, and KS calibration curves. In comparison with the DMB spectrophotometric method, this multiplex tandem mass spectrometry method allows GAG fractionation, thus a differentiation of MPS types, except for MPS I and II which are characterized by the same GAG profile. The devised method is a useful and reliable tool for diagnosis of MPS patients, as well as their monitoring and follow up, as shown by longitudinal studies.     

用炼锌厂废泥制取硫酸铜、海绵镉和硫酸锌

研究了以炼锌厂废泥为原料,经氧化、酸浸、中和沉淀、稀硫酸溶解、置换等步骤制取硫酸铜、海绵镉和硫酸锌的工艺.     

聚硅硫酸亚铁的混凝特性及影响因素

混凝剂;聚合硫酸铁;水处理;聚硅硫酸亚铁的混凝特性及影响因素     

Thermal decomposition behavior of the rare-earth ammonium sulfate R2(SO4)3·(NH4)2SO4

Rare-earth ammonium sulfate octahydrates of R₂(SO₄)₃·(NH₄)₂SO₄·8H₂O (R=Pr, Nd, Sm, and Eu) were synthesized by a wet process, and the stable temperature region for the anhydrous R₂(SO₄)₃·(NH₄)₂SO₄ form was clarified by thermogravimetry/differential thermal analysis, infrared, Raman, and electrical conductivity measurements. Detailed characterization of these double salts demonstrated that the thermal stability of anhydrous R₂(SO₄)₃·(NH₄)₂SO₄ is different between the Pr, Nd salts and the Sm, Eu salts, and the thermal decomposition behavior of these salts was quite different from the previous reports.     

Aqueous solubilities of praseodymium,europium, and lutetium sulfates

The aqueous solubilities of finely divided Pr₂(SO₄)₃·8H₂O(cr), Eu₂(SO₄)₃·8H₂O(cr), and Lu₂(SO₄)₃·8H₂O(cr) have been measured as a function of time at 25°C using isothermal saturation. Solubilities of the latter two salts showed a steady decrease with time, whereas Pr₂(SO₄)₃·8H₂O(cr) showed no such variation within the accuracy of the determinations. The turbidities of these filtered saturated solutions also decreased with time, and indicate that some colloidal rare earth sulfates were present. These colloidal particles (<0.2 m) have a large surface area, which contributes to the Gibbs energy of the solid phase, thus giving rise to enhanced solubilities. The micro-particles also grow with time, thereby reducing the surface area contribution to the Gibbs energy and also leaving fewer particles to pass through the filters. Extrapolation of solubilities to infinite time gives the solubilities of macrocurstalline Eu₂(SO₄)₃·8H₂O and Lu₂(SO₄)₃·8H₂O. Previous solubility data for Lu₂(SO₄)₃, at 20 and 40°C, yield an interpolated value at 25°C that is about 30% low. Densities were also measured at several concentrations of each salt.     

Capillary electrophoresis and enzyme solid phase assay for examining the purity of a synthetic heparin proteoglycan-like conjugate and identifying binding to basic fibroblast growth factor

Interaction of basic fibroblast growth factor (bFGF) with heparin/heparan sulfate proteoglycans protects the growth factor against proteolytic degradation and is essential for its cellular activity. Although the structural requirements of heparin and heparan sulfate for the high-affinity binding to bFGF have been extensively examined, studies on intact heparin proteoglycans are limited. In this report, the purity and the binding ability of a heparin proteoglycan-like molecule-the heparin-bovine serum albumin (heparin-BSA) conjugate-was examined using capillary zone electrophoresis (CZE). Furthermore, the affinity of bFGF binding to the heparin-BSA conjugate was studied using an enzyme solid-phase assay. Chondroitin sulfate, dermatan sulfate, hyaluronan, heparan sulfate and variously sulfated disaccharides derived from heparin and heparan sulfate were also studied for their ability to compete with the binding of bFGF to heparin. Heparin-BSA conjugate was synthesized by reductive amination and, following precipitation with 1.5 vols of ethanol-sodium acetate, it was obtained free of contaminating heparin. Heparin-BSA-bFGF conjugate was obtained following incubation of heparin-BSA with bFGF for 2 h at 37 degrees C. Intact heparin, heparin-BSA and heparin-BSA-bFGF conjugates were completely resolved by CZE using 50 mM phosphate, pH 3.5, as operating buffer, reversed polarity (30 kV) and detection at 232 nm. Competitive solid phase assay showed that, among the glycosaminoglycans tested, heparin exhibits the highest affinity binding to bFGF (IC(50) = 6.4 nM). Heparan sulfate showed a lower affinity as compared with that of heparin, whereas all other glycosaminoglycans and heparin/heparan sulfate-derived disaccharides tested showed minute effects. The developed CZE method is rapid and accurate and can be easily used to identify bFGF-interacting heparin preparations of biopharmaceutical importance.     

无机高分子聚合铁盐类混凝剂制备方法评述(英文)

综述了无机高分子聚合铁盐类混凝剂的几种生产制备方法.对用硫酸亚铁经催化氧化法和直接氧化法制备聚合硫酸铁,用各种含铁工业废渣制备复合聚铁,以及采用生物和电化学方法制备聚铁类混凝剂等方法的优缺点等作了较全面评述.还对固体聚合铁的生产及液体聚合铁混凝剂的稳定性进行了讨论,对目前聚合铁生产中存在的问题及发展方向提出了建议.     

气相色谱-质谱联用测定化妆品中硫酸二甲酯与硫酸二乙酯

建立了同时测定化妆品中硫酸二甲酯和硫酸二乙酯的气相色谱-质谱(GC-MS)联用法。样品经溶剂提取后采用GC-MS测定,外标法定量。水基类、乳液类、膏霜类、啫喱类和粉类化妆品的方法检出限均为1.5 mg/kg,定量下限均为5.0 mg/kg;蜡基类化妆品的检出限为3.0 mg/kg,定量下限为10.0 mg/kg;油状化妆品的方法检出限为5.0 mg/kg,定量下限为16.0 mg/kg。目标物在0.25~20.0 mg/L范围内线性良好,相关系数均大于0.99,硫酸二甲酯的平均回收率为83.8%~104.7%,相对标准偏差为2.7%~8.2%;硫酸二乙酯的平均回收率为84.7%~104.8%,相对标准偏差为3.5%~8.7%。方法前处理简单,灵敏度高,可满足水基类、乳液类、膏霜类、啫喱类、粉类和油状化妆品中硫酸二甲酯和硫酸二乙酯的检测要求。