环氧衍生物开环法制备壳聚糖季铵盐

采用异丙醇为溶剂,以壳聚糖（CTS）、2,3-环氧丙基三甲基氯化铵（GTA）为原料,用环氧衍生物开环法制备了壳聚糖季铵盐（HACC）,通过单因素实验,考察了反应物摩尔比、反应时间、反应温度等因素对产物取代度的影响,结果表明,制备壳聚糖季铵盐的最优工艺条件为：n（CTS）∶n（GTA）=1∶4,壳聚糖相对分子质量（简称分子量,下同）3.2×10^5,碱化时间14 h,预处理壳聚糖含水率20%,反应pH=7,反应温度75℃,反应时间8 h。通过红外光谱、扫描电镜、热重分析对壳聚糖、壳聚糖季铵盐的结构、外观形貌、热稳定性进行了表征与分析,结果表明,壳聚糖季铵化改性以N取代为主,改性后外貌和粒度有了明显变化,并且热稳定性降低。

反应温度对猪油环氧化的影响

猪油在甲酸催化下 ,按H2 O2 /C =C摩尔比为 1 5∶1用双氧水进行原位环氧化。通过考察温度对产物碘值和环氧指数的影响 ,发现随温度的升高 ,产物碘值逐渐减小 ;环氧指数先增大后减小 ,6 3℃时达到最大值。

船舶整体艉管环氧浇注安装方法

介绍船舶整体艉管环氧浇注安装法,即直接通过环氧树脂将已装配的轴承和各种艉管附件进行固定,缩短安装时间,提高效率,降低了风险,满足了船台周期的要求。逐渐成为造船厂优先选择的工艺方法。

环氧衍生物开环法制备壳聚糖季铵盐的工艺研究

采用异丙醇为溶剂,以壳聚糖(CTS)、2,3-环氧丙基三甲基氯化铵(GTA)为原料,用环氧衍生物开环法制备了壳聚糖季铵盐(HACC)。通过单因素实验,研究了反应物摩尔比、反应时间、反应温度等因素对产物取代度的影响。结果表明,制备壳聚糖季铵盐的最优工艺为:nCTS∶nGTA=1∶4,反应时间8 h,反应温度75℃,反应pH值为7,碱化时间14 h,壳聚糖分子量3.2×105,反应体系含水率20%。通过红外光谱、扫描电镜、热重仪对壳聚糖、壳聚糖季铵盐的结构、外观形貌以及热稳定性进行了表征与分析,结果表明壳聚糖季铵化改性以N-取代为主,改性后外貌和粒度有了明显变化,且热稳定性降低。

用环氧砂浆固定法修复失效的重型剪机地脚螺栓

1 设备简介广西柳钢中板厂2号电动剪板机,型号为 Q_(11)25×3800,长6700毫米,宽3560毫米高5000毫米,重85吨,。剪机的左右两机架原设计各有5颗 M42地脚螺栓固定,机架之间由纵剪刀床相连接,如图1所示。

芳纶纤维湿法缠绕容器研究进展

研究了高性能 Ｆ—１２ 芳纶纤维的湿法成型工艺，研制了与 Ｆ—１２ 纤维匹配性良好的湿法环氧配方， 同时进行了 Φ１５０ ｍｍ 、Φ４８０ ｍ ｍ 容器的湿法成型工艺参数的优化试验， 初步探讨了湿法成型中的含胶量控制技术。结果表明， Ｈ Ｒ１８ 湿法配方与 Ｆ—１２ 纤维的匹配性和工艺性良好， 而且湿法成型工艺参数经优化后可明显提高容器的特性系数 Ｐ Ｖ／ Ｗｃ 值。

1,3-丙二醇的生产与应用

1,3-丙二醇是合成聚对苯二甲酸丙二醇酯 (PTT)的单体 ,PTT具有广泛应用领域 ,本文着重阐述 1,3-丙二醇的性能、合成及几种生产方法的比较。

橡胶籽油基多元醇的制备与表征

以环氧橡胶籽油(ERSO)为原料,甲醇和异丙醇为开环试剂,氟硼酸为催化剂,制备橡胶籽油基多元醇,以产物羟值为指标对制备工艺进行了优化,并对产物进行了表征。研究结果表明,橡胶籽油基多元醇的最佳制备条件为反应时间30 min,反应温度70℃,醇与ERSO的质量比为4∶1,氟硼酸用量为ERSO质量的1%,异丙醇与甲醇质量比为1∶1。通过验证实验可知,在此条件下制备的橡胶籽油基多元醇酸值为2.68 mg/g,羟值为219.32 mg/g,平均相对分子质量为870.21,含水量为0.08%,黏度为4 791 m Pa·s。同时,通过FT-IR、~1H NMR和^(13)C NMR分析表征了橡胶籽油基多元醇的化学结构,结果表明,ERSO中的环氧基发生了开环反应,生成了多元醇。

现浇彩色水磨石地面空鼓的灌浆粘补

介绍了采用环氧灌浆法粘补现浇彩色水磨石地面空鼓缺陷．着重叙述了粘补剂组成与制备、粘补工艺过程。实际证明，其在技术上是可行的．在经济上是合理的，值得推广应用。

洛阳体育场改造加固工程设计

通过对洛阳体育场改造加固工程设计加以总结,介绍该大型露天场所的加固改造要点和工程竣工后的社会效益。

混胺硫酸拆分生产工艺研究

为解决企业合成磷霉素钠所遇到的排放处理等实际问题,研究采用右环氧工艺合成法,以右旋1,2-环氧顺丙烯磷酸左旋苯乙胺盐作为起始原料,来拆分混旋苯乙胺,使其变废为宝,重新作为合成磷霉素钠等产品的基础原料。以年产万吨的磷霉素钠计算,每年可以消除约上万吨废弃物的排放,而且可以合成约2 000 t的手性苯乙胺,产生数千万元的经济效益。

压力前池防渗处理

用上堵下截法处理压力前池渗漏,确保厂房基础安全。

Preparation and properties of PEO/LiClO_4/KH560-SiO_2 composite polymer electrolyte by sol-gel composite-in-situ method

Composite polymer electrolytes based on polyethylene oxide(PEO) were prepared by using LiClO4 as doping salt and silane-modified SiO2 as filler. SiO2 was formed in-situ in (PEO)8LiClO4 matrix by the hydrolysis and condensation reaction of Si(OC4H9)4. The crystallinity,morphology and ionic conductivity of composite polymer electrolyte films were examined by differential scanning calorimetry,scanning electron microscopy,atom force microscopy and alternating current impedance spectroscopy,respectively. Compared with the crystallinity of the unmodified SiO2 as inert filler,that of composite polymer electrolytes is decreased. The results show that silane-modified SiO2 particles are uniformly dispersed in (PEO)8LiClO4 composite polymer electrolyte film and the addition of silane-modified SiO2 increases the ionic conductivity of the (PEO)8LiClO4 more noticeably. When the mass fraction of SiO2 is about 10%,the conductivity of (PEO)8LiClO4-modified SiO2 attains a maximum value of 4.8×10-5 S·cm-1.

砼防碳化处理在五里桥泵站中的应用

通过具体工程实例,详细阐述了五里桥泵站中砼防碳化处理的各种方法。针对不同的碳化深度和结构部位,综合考虑加固维修后的结构安全耐用、工程投资最省以及便于施工等诸多因素,相应采取不同的设计方案。对今后砼防碳化处理具有很好的参考借鉴价值。

Ship-in-bottle synthesis of NaY zeolite encapsulated Cosalen complex and its catalytic performance for cyclohexane oxidation

N, N＇-bis （salicylidene） ethylenediiminocobalt （Cosalen） was encapsulated into microporous NaY zeolite via the technique of ＂ship-in-bottle＂. The encapsulated complex （Cosalen-NaY） was characterized by Fourier-transform infrared spectrum, ultraviolet-visible spectrum, Brunaner-Emmett-Teller surface areas, X-ray diffraction, thermogravimetry-differential thermal analysis and scanning electron microscope. The reaction of cyclohexane oxidation using oxygen was chosen to investigate the catalytic performance of Cosalen-NaY, and the effects of oxygen pressure, temperature and reaction time were also studied. The results show that Cosalen complex is encapsulated into the supercage of the zeolite and the structure of NaY zeolite remains integrity and the thermal stability of Cosalen is greatly enhanced after encapsulation. Cosalen-NaY shows the better activity in the oxidation of cyclohexane without reductant and solvent. The conversion of cyclohexane is up to 13.4% at 150 ℃ for 3 h under oxygen pressure of 0.85 MPa, with the higher total selectivity to cyclohexanol, cyclohexanone, cyclohexyl hydroperoxide （CHHP） and acid （79.2%） than the neat complex （55.5%）. NaY zeolite cartier maybe contributes to the results. There is no obvious induction period to initiate the reaction; furthermore, the amount of CHHP among the products is small, which indicates that the Cosalen-NaY has the strong ability to accelerate the decomposition of CHHP. Recycling tests show that the hybrid material can be used repeatedly with a negligible loss of active sites.

Start-up and Performance of a Novel Reactor----Jet Biogas Inter-loop Anaerobic Fluidized Bed

A novel anaerobic reactor, jet biogas inter-loop anaerobic fluidized bed （JBILAFB）, was designed and constructed. The start-up and performance of the reactor was investigated in the Process. of .artificial glucose wastewater treatment. With the wastewater recycle ratio of 2.5 ： 1, the recycled wastewater with biogas could mix sludge and wastewater in the JBILAFB reactor completely. The start-up of the JBILAFB reactor could be completed in less than 70 d through maintenance of hydraulic retention time （HR^I＂） and stepwise increase of feed total organic carbon （TOC） concentration. After the start-up, with the volumetric TOC loadings of 14.3 kg·m ^-3·d^-1, the TOC removal ratio, the effluent pH, and the volatile fatty acids （VFA）/alkalinity of the JBILAFB reactor were more than 80%, close to 7.0 and less than 0.4, respectively. Moreover, CH4 was produced at more than 70% of the theoretical value, The reactor exhibited high stability under the condition of high volumetric TOC loading. Sludge granules in the JBILAFB reactor were developed during the start-up and their sizes were enlarged with the stepwise increase of volumetric TOC loadings from 0.8 kg.m^-3.d ^-1 to 14.3 kg.m^-3.d^-1. Granules, an offwhite color and a similar spherical shape, were mainly comprised of global-like bacteria. These had good methanogenic activity and settleability, which were formed probably through adhesion of the bacteria. Some inorganic metal compounds such as Fe, Ca, Mg, Al, etc. were advantageous to the formation of the granules.

Cycloaddition of CO_2 and propylene oxide by using M(HBTC)(4,4'-bipy)·3DMF(M=Ni,Co,Zn) metal-organic frameworks

Three pillar-layered metal-organic frameworks（MOFs） based on M（HBTC）（4,4＇-bipy）.3DMF（M =Ni, Co, and Zn; HBTC = 1,3,5-benzenetricarboxylic acid, 4,4＇-bipy = 4,4′-bipyridine） were synthesized using a solvothermal method. Zn（HBTC）（4,4＇-bipy）.3DMF was synthesized for the first time using both a solvothermal and microwave method, and subsequently characterized by various physicochemical methods. The structure of M（HBTC）（4,4＇-bipy）.3DMF consisted of honeycomb grid layers of M2＋ ions and BTC units, which were further linked by the 4,4＇-bipy pillars to form a three-dimensional highly porous framework. All the MOFs displayed excellent synergistic catalytic properties with alkyl ammonium halides（TBAX） in the solventless fixation of CO_2 with epoxides to produce cyclic carbonates. The catalytic activities of these MOFs followed the trend Zn Co Ni,which was explained by the acid-base bifunctional properties. The microwave-synthesized Zn（HBTC）（4,4＇-bipy）.3DMF material exhibited physical, chemical, and catalytic properties that were similar to those of the catalyst obtained using a conventional solvothermal synthesis. The scope of various parameters, including recyclability, was studied, and a plausible reaction mechanism was suggested.

Study on Kinetics of Cathodic Reduction of Dissolved Oxygen in 3.5% Sodium Chloride Solution

Electrochemical reduction of dissolved oxygen in seawater on metals is of great importance for corrosion studies. The present paper studied cathodic reduction of dissolved oxygen on Q235 carbon steel in 3.5% sodium chloride （NaCl） solutions by cyclic voltammetry （CV）, electrochemical impedance spectroscopy （EIS）, rotating disk electrode （RDE） and rotating ring-disk electrode （RRDE）. The cyclic voltammetric results demonstrated the cathodic process on Q235 carbon steel in O2-saturated 3.5% NaCl solution contains three reactions： dissolved oxygen reduction, iron oxides reduction and hydrogen evolution. The peak potential of oxygen reduction reaction （ORR） is - 0.85 V vs Ag/AgCl, 3 molL^-1 KCI. The EIS results indicated that the ORR occurring on Q235 carbon steel is a 4-electron process and that no finite diffusion is caused by the intermediate of H2O2 produced by ORR. The RDE and RRDE voltammograms confirmed the EIS results and it was found that the number of transferred electrons for ORR was nearly 4, i.e., dissolved oxygen reduced to water.

广州石化重催四机组改造安装分析

重催旧机组由于振动大、效率低,已无法满足生产的要求,为此对四机组进行了改造。调整设备的某些参数、利用旧基础,采用环氧砂浆座浆法和合理的对中安装工序。改造后,四机组能满足生产长期稳定运行的需要。

A direct electrochemical route from oxides to TiMn_2 hydrogen storage alloy

This study is for investigating the direct electro-deoxidation of mixed TiO2-Mn02 powder to prepare TiMn2 alloy in molten calcium chloride. The influences of process parameters, such as sintering temperature, cell voltage, and electrolysis time, on the electrolysis process were examined to investigate the mechanism of alloy formation. The composition and morphology of the products were analyzed by XRD and SEM, respectively. The electrochemical property of TiMn2 alloy was investigated by cyclic voltammetry measurements. The results show that pure TiMn2 can be prepared by direct electrochemical reduction of mixed TiO2/Mn02 pellets at a voltage of 3.1 V in molten calcium chloride of 900 ℃ for 7 h. The electro-deoxidation proceeds from the reduction of manganese oxides to Mn, which is reduced by Ti02 or CaTiOB to form TiMn2 alloy. The cyclic voltammetry measurements using pow- der microelectTode show that the prepared TiMn2 alloy has good electrochemical hydrogen storage property.