多羟基POSS对改性环氧网络热性能的影响

为改性双酚A型环氧树脂(DGEBA)的热性能,利用γ-氨丙基T8(A-POSS)与苯基缩水甘油醚(PGE)反应制得改性剂多羟基POSS(SP2-POSS),并利用不同质量分数的SP2-POSS(分别为8%,15%,30%,45%,60%,75%)掺杂改性DGEBA高分子交联体系.对改性的DGEBA体系分别进行结构和热性能测试,结构测试结果表明,改性后的体系确实有多羟基存在;热性能测试结构表明,多羟基的存在使得体系的交联度提高,从而使反应固化热、玻璃化转变温度、热失重温度有所提高,其中含75%的改性DGEBA高分子体系具有最好的热性能.     

Nano-scratch test for POSS films based on vinyltrimethoxysilane and modified with titanium tetrabutoxide

Polyhedral oligomeric Silsesquioxanes (POSS) derived from vinyhrimethoxysilane (VMS) and modified with titanium tetrabutoxide (TTBO) (PVT) were prepared by sol-gel process catalyzed by hydrochloric acid (molar ratio: [HCl]/Si = 0.05), and heating at 45℃ during 3 days. The PVT films (f-PVT) with different TTBO content, 5, 20 and 25wt% TTBO, were prepared by adding the stoichiometric amount of benzoyl peroxide (BPO) to PVT solutions in ethanol, dip-coating over glass substrates, and curing using an appropriate thermal cycle and time. The hardness and elastic modulus of f-PVT were tested by continuous stiffness measurement (CSM) of nanoindentation, and the tribological behaviors were comparatively investigated with a nanoscratch test. The influenee of the different TTBO contents on the mechanical properties of f-PVT was discussed.The scratch and friction coefficient prufiles of f-PVT were illustrated. As the results of the test, f-PVT with 20% TTBO showed the better scratch resistance and tribological behavior.     

Influence of POSS modifier on NLO properties of the hybrid materials

The sol-gel-based nonlinear optical (NOL) mate-rials can be divided into two classes: (1) the guest-host-doped systems and (2) the chromophore boned tomain-chain hybrids[1, 2]. The intrinsic problems in thefirst class are the weak interactions between guest andhost parts. This issue can be solved by linking NLO-ac-tive organic chromophores to the inorganic matrix (thesecond class). One of the various methods to fabricatethis class of the NLO hybrid materials is when the de-sired chromophor…     

Cage and ladder structures of silsesquioxanes characterized by UV-MALDI-TOF mass spectrometry

The molar mass distribution of SSO in the first generation derived from the hydrolytic condensation of two trialkoxysilanes, [3- (Methacryloxy) propyl] trimethoxysilane (MPMS) and vinyltrimethoxysilane (VMS), are determined by UV-MALDI-TOF MS. The comparisons of theoretical masses with experimental masses are calculated using the proposed compounds, which are assigned to formulas Tn (OH)_m, T_n (OMe)_y or T_n(OH)_x(OMe)_y[T=RSiO_(1.5-(x+y)/2n), R=——(CH_2)_3OOCCH(CH_3)CH_2 and——CHCH_2]. Both the proposed cage and ladder structures of SSO derived from similar sol-gel process of monomers are illustrated. The causes for the difference in structures between SSO_M and SSO_v is discussed as well.     

直接法制备三乙氧基硅烷的正交实验研究

为了提高产率、降低成本,采用反歧化法制备了催化剂氯化亚铜,又以氟化铵为助催化剂进行直接催化硅粉和乙醇反应制备三乙氧基硅烷。采用XRD、XRF和SEM对催化剂进行了表征。用正交实验方法探索了不同的工艺条件对硅粉转化率、产物选择性和产物收率的影响。正交实验结果表明,各因素对产物收率影响由大至小的顺序为：主催化剂占硅粉质量比...     

Effect of corrosive solutions on C-S-H microstructure in portland cement paste with fly ash

By means of ²⁹Si and ²⁷Al magic angle spinning nuclear magnetic resonance (MAS NMR) combined with deconvolution technique, X-ray diffraction (XRD), scanning electron microscopy (SEM) as well as energy dispersive X-ray system(EDX), the effect of 5 wt% corrosive solutions (viz. 5 wt% Na₂SO₄, MgSO₄, Na2SO4+NaCl and Na₂SO₄+NaCl+Na₂CO₃) on C-S-H microstructure in Portland cement containing 30 wt% fly ash was investigated.The results show that, in MgSO₄ solution, Mg²⁺ promotes the decalcification of C-S-H by SO ₄ ^2- ,increasing silicate tetrahedra polymerization and mean chain length (MCL) of C-S-H. However, the substituting degree of Al³⁺ for Si⁴⁺ (Al[4]/Si) in the paste does not change evidently. Effect of Na²SO⁴ solution on C-S-H is not significantly influenced by NaCl solution, while the MCL and Al[4]/Si of C-S-H in fly ashcement paste slightly change. However, the decalcification of C-S-H by SO ₄ ^2- and CO ₃ ^2- attack, as well as the activation of fly ash by SO ₄ ^2- attack will increase the MCL and Al[4]/Si, which are both higher than that under Na₂SO₄ corrosion, MgSO₄ or Na₂SO₄ +NaCl coordination corrosion.     

纳米碳管／二氧化硅复合凝胶玻璃的XPS研究

分别以物理掺杂和化学掺杂的方式,采用溶胶-凝胶法制备了未经表面修饰纳米碳管（CNTs）和经r-氨基丙基三乙氧基硅烷（NH2（CH2）3Si（OC2H5）3,APTES）修饰纳米碳管的有机改性SiO2复合凝胶玻璃。在此基础上,以X射线光电子能谱（XPS）为表征手段,对所得两种复合凝胶玻璃中SiO2基质和掺杂CNTs的化学状态进行研究。结果表明,掺杂CNTs改变了复合凝胶玻璃中C和O的原子百分比,对SiO2基质的网络结构产生影响,但对SiO2基质的组成未产生显著影响;无论是在物理掺杂还是化学掺杂的有机改性SiO2复合凝胶玻璃中,CNTs与SiO2间均存在一定的Si—C结合键;在CNTs-SiO2复合凝胶玻璃中,以APTES作为桥梁,实现了CNTs与SiO2网络间的化学键合。     

功能化四氧化三铁的合成和表征及其对钙离子的吸附

结合磁性纳米颗粒及功能基团各自的特性,设计了具有可以螯合金属离子的功能型磁性纳米颗粒,以获得选择性高、操作简易且回收后可重复利用的钙离子吸附剂.以三氯化铁和硫酸亚铁为铁源,采用化学共沉淀法在氩气保护下制备磁性纳米颗粒四氧化三铁;通过硅烷化反应在磁性纳米颗粒上依次包覆二氧化硅及γ-氨丙基三乙氧基硅烷.以甲基丙烯酸及乙二胺为原料通过迈克尔加成及酰胺化反应合成了含酰胺键、酯基、氨基功能基团的磁性纳米颗粒.X-射线粉末衍射线、傅立叶红外、扫描电镜、热重分析、X-射线光电子能谱等技术的分析结果表明已合成各中间体及功能化的纳米颗粒.原子吸收光谱研究表明该纳米颗粒可通过其配位基团按理论配比螯合钙离子.随着功能基含量的增加,吸附钙离子的能力也会随之增强,因此,含较多功能基的该类磁性纳米颗粒有望用作水中钙离子的吸附剂.     

嵌段改性聚氨酯胶粘剂的研究

应用本体聚合的方法合成了聚甲基丙烯酸甲酯羟基预聚物(PMMA-BDO)嵌段改性的聚氨酯(PU)胶粘剂.采用正交实验的方法考察了扩链剂(BDO)与聚酯二元醇(PBA)摩尔比、二苯基甲烷-4.4-二异氰酸酯(MDI)中-NCO与聚酯二元醇中的-OH摩尔比、PMMA-BOO与PBA质量配比对嵌段改性聚氨酯胶粘剂剥离强度的影响,从中优化出最佳反应条件,同时用红外光谱进行了结构分析.     

Synthesis of the novel fluoride-containing organic silane

A fluoride-containing organic silane was synthesized by the reaction of N-ethyl-N-hydroxy-ethyl perfluorinated octyl sulfonamide (EHPOS), N-(β-aminoethyl)-γ-aminopropyl trimethoxy silane (ATS) and cis-butenedioic anhydride (CA). The experimental results show that the yield of product is up to 87% when the molar ratio of EHPOS: CA: ATS is 1: 1.05: 1.1. EHPOS and CA were maintained at 115 °C for 3 hours, then after cooling the reaction solution to 75 °C, ATS was added and reacted for another 3.5 hours at 145 °C. The structure of the product and thermal properties were characterized by Fourier transform infrared (FTIR) and thermogravimetric analysis (TGA), respectively. Results show that fluoride-containing organic silane has excellent thermal stability below 185 °C. Funded by the Military Defense Project (No. 200701HX03)     

磁性MnFe2O4/Ag复合纳米粒子的 制备与抑菌性能测试

采用水热法合成了磁性空心MnFe2O4纳米粒子,然后用3-氨丙基三乙氧基硅烷对其表面进行了改性并吸附银离子,还原后成功制备了磁性MnFe2O4/Ag复合纳米粒子,并采用X射线衍射仪、透射电镜、磁强计、紫外光谱等对试样进行了表征.通过抑菌圈法对MnFe2O4/Ag复合纳米粒子的抑菌性能进行了测试.结果表明:磁性空心MnFe2O4纳米粒子没有抑菌性能;MnFe2O4/Ag对大肠杆菌的抑菌圈半径为1.78 cm,对金黄色葡萄球菌的抑菌圈半径为2.14 cm;MnFe2O4/Ag的抑菌持久性检测结果说明,所制备的载银磁性复合纳米粒子抑菌剂的稳定性较好,抑菌性能较持久.     

Preparation and Property of Bisphenol A Bis （diphenyl phosphate） Oligomer

Bisphenol A bis(diphenyl phosphate)oligomer(BDP)is prepared successfully from the reactants consisting of phosphorus oxychloride(POCl3),bisphenol A and phenol with a Friedel-Crafts catalyst.The resultant products were examined with thermo-gravimetric analysis(TGA)and high performance liquid chromatography(HPLC).Thermogravimetry data shows that BDP decomposes at 375 ℃ when 5% weight lost.Experiments results show that catalyst is preferably AlCl3 and the amount of it is preferably 1% relative to bisphenol A by mole.POCl3/bisphenol A mole ratio is preferably about 5∶1 to 6∶1.Experiments unclosed that a seal apparatus is very important to the properties of product.     

Microstructural Evolution Mechanism of C-(A)-S-H Gel in Portland Cement Pastes Affected by Sulfate Ions

The microstructural evolution of C-(A)-S-H gel in Portland cement pastes immersed in pure water and 5.0 wt% Na₂SO₄ solution for different ages was comparatively investigated, by means of ²⁹Si NMR spectroscopy, and SEM-EDS analysis. Additionally, molecular dynamics simulation was performed to study the aluminum coordination status and interaction of sulfate ions in C-(A)-S-H gel. The results showed significant changes in the microstructural evolution of C-(A)-S-H gel in Portland cement paste. Sulfate attack has decalcifying and dealuminizing effect on C-(A)-S-H gel which is evident from increase in mean chain length (MCL) and decrease in Ca/Si & Al[4]/Si ratios of C-(A)-S-H gel. Additionally, Molecular dynamics simulation proves that Al[4] substituted in silicate chains of C-(A)-S-H gel is thermodynamically metastable, which may explain its migration from the silicate chains and transformation to Al[6], thus lowering the Al[4]/Si ratio of C-(A)-S-H gel. SO₄^2- ions can carry the interfacial Ca²⁺ ions into the pore solution by the diffusion-absorption-desorption process, which unravels the mechanism of sulfate attack on C-(A)-S-H gel.     

DNT同分异构体的能量分辨质谱

用能量分辨质谱（ＥＲＭＳ）来鉴别质谱分析中的同分异构体化合物，系统探讨了同分异构的硝基芳香化合物２，３－ＤＮＴ和３，５－ＤＮＴ（分子量为１８２）在电子轰击（ＥＩ）方式下，裂分途径与其分子内能的相互关系以及离子的结构和裂分途径相对于碰撞能量（ＣＥ）的依赖关系（裂分曲线）．结果表明，利用同分异构化合物在能量分辨中的显著差异可以辨别它们的结构。     

Chemical component analysis of volatile oil in drug pair Herba Ephedrae-Ramulus Cinnamomi by GC-MS and CRM

Active volatile components in drug pair(DP)Herba Ephedrae-Ramulus Cinnamomi(HE-RC),single drug HE and RC were analyzed by gas chromatography/mass spectrometry(GC/MS),chemometric resolution method(CRM)and overall volume integration.By means of CRM,the two-dimensional data obtained from GC-MS instruments were resolved into a pure chromatogram and a mass spectrum of each chemical compound.In total,97,62,and 78 volatile chemical components in volatile oil of HE,RC,and DP HE-RC,were respectively determined qualitatively and quantitatively,accounting for 90.08%,91.62%,and 89.76% total contents of volatile oil of HE,RC,and DP HE-RC respectively.It is further demonstrated that the numbers of volatile components of DP HE-RC are almost the sum of those of two single drugs,but some relative contents of them are changed.Some new components,such as 1,6-dimethylhepta-1,3,5-triene,tetracyclo[4.2.1.1(2,5).0(9,10)]deca-3,7-diene,globulol and(E,E)-6,10,14-trimethyl-5,9,13-pentadecatrien-2-one are found in DP HE-RC because of chemical reactions and physical changes during decoction.     

Si(NH)2热分解法制备Si3N4晶须的影响因素

利用Si（NH）2热分解法制备了Si3N4晶须，对实验原理和实验过程进行了详细描述，对实验中存在的温度、残留碳、微量氧、坩埚材质等可能影响晶须生长的诸多因素进行了分析讨论，说明了诸影响因素的影响程度和参与机理。通过对工艺过程中诸影响因素的控制，可以制备高质量Si3N4晶须或改性Si3N4晶须，对研究开发该法批量生产性能优异的Si3N4晶须的工作具有重要的参考意义。     

2-取代-2，3-二氢-4(1H)-喹唑啉酮衍生物合成方法

在氯化铝催化作用下,以水为溶剂,将2-氨基苯甲酰胺和醛/酮室温研磨后,温度为60℃时加热反应,可有效环化合成一系列2-取代-2,3-二氢-4(1H)-喹唑啉酮衍生物。比较不同催化剂的催化活性,考察了催化剂和水的用量对收率的影响。结果表明,在n(2-氨基苯甲酰胺)/n(醛/酮)=1：1,催化剂摩尔分数为1％,水体积2 m...     

Hydration Characteristics of Sodium Sulfate Slag Cement System

The hydration characteristics by thermal analysis ( DTA ) were determined, and an isothermal calorimeter (IC) was used to study the pastes . The experimental results indicate: (1) The main hydration products of SSC are C-S-H( I ) gel with a low Ca/Si ratio, crystalline Thomsonite-type and AFt-type phases containing certain alkali cations; (2) No phases of the AFm-type and high alkaline Ca( OH)2 in SSC system could benefit the hydrated cements to improve its strength and durability; (3) Crystalline Thomsonite-type and AFt-type phases containing Na will greatly reduce free alkali and alleviate the harmness of alkali aggregate reaction ( AAR) in SSC system; (4) Similar to ordinary Portland cement( OPC), the hydration process of SSC could be classified into five stages : initial, induction, acceleration, deceleration and decay; (5) Regardless of the activator used, the apparent activation energy is higher with the increased slag in cement system, and the rising temperature could promote the hydration of SSC.     

木质素单体模化物的热解与产物分析

采用苯酚、邻苯二酚、愈创木酚和紫丁香酚为木质素单体模化物,利用两段裂解反应器-在线气相色谱仪（GCs）进行热解实验和产物分析,采用多色谱柱对无机气体（IGs）、C₁~C₅烃（C₁~C₅ LHs）、非芳基含氧化合物、酚和芳烃进行定量分析,以确定羟基和甲氧基对木质素热解过程中开环反应及产物分布的影响. 结果显示：羟基和甲氧基可以提高模化物的转化率,且羟基和甲氧基的存在影响芳基开环反应、芳基取代反应和重排反应间的竞争关系,使热解产物分布存在明显差异. 4种模化物热解产物主要是芳环的开环反应产物,包括IGs（质量分数为27.29%~33.56%）和C₁~C₅烃（20.46%~39.51%）. 一氧化碳产率（23.82%~29.18%）随羟基数增加而升高,随甲氧基数增加而降低;二氧化碳产率（0.19%~9.61%）随甲氧基数增加而升高. 羟基和甲氧基的存在降低了C₁~C₅烃的质量选择性,促进了烷基苯、大分子化合物和焦炭的形成.     

雷尼替丁吡啶钌体系伏安行为的研究

雷尼替丁是含呋喃环的胺类化合物,加入吡啶钌使其电化学行为发生改变,从而导致雷尼替丁和吡啶钌电化学发光共反应。本文采用循环伏安技术,详细地研究了该体系的电化学行为和电化学发光行为。实验表明在磷酸盐缓冲溶液中(pH7.50),雷尼替丁的电化学发光共反应体系,发光稳定性好、灵敏度高。