新型受阻酚类季鏻盐改性蒙脱土的合成及应用

以2,6-二叔丁基苯酚(2,6酚)、盐酸、多聚甲醛及三苯基膦为原料合成新型受阻酚季鏻盐,通过IR、1 H-NMR、熔点的测定对产物进行表征。筛选得到最佳反应条件:甲苯为溶剂,2,6酚、盐酸、多聚甲醛、三苯基膦反应摩尔比r=1∶15∶15∶1,反应温度109℃,反应时间为12h。该条件下产率达到89.1%。使用受阻酚季鏻盐改性蒙脱土(OMMT),应用于无规共聚聚丙烯(PPR),结果表明改性后的PPR具有良好的耐加工性能。     

聚苯乙烯交联微球的氯甲基化方法研究

以异戊醇、多聚甲醛及氯化亚砜为主要原料,合成了氯甲基化试剂氯甲基异戊醚。并采用原位法对聚苯乙烯交联微球进行氯甲基化。利用傅里叶红外光谱仪对产物结构进行了表征,以莫尔滴定法对氯球的氯含量进行了测定。考察了各物料配比、反应时间对氯甲基化反应的影响规律。获得最佳反应条件为:异戊醇∶多聚甲醛∶氯化亚砜∶聚苯乙烯∶四氯化锡∶二氯甲烷(均为物质的量比)=1∶2.4∶2.4∶7.2∶0.8∶7.2,氯甲基异戊醚合成阶段反应温度为3~5℃,反应时间为7h;氯甲基化合成阶段反应温度为15~20℃,反应时间为12h,总计反应时间为19h。制得的氯球的氯含量可达18%(wt,质量分数)。     

氨基硫脲/季铵木质素对铂的吸附

木质素及其衍生物因具有经济高效和无污染等特点,在有价金属提取和有毒金属离子去除等领域具有广阔的应用前景。本研究采用氨基硫脲/季铵木质素吸附铂,通过FTIR分析揭示了吸附过程的机制,考察了盐酸浓度、Pt(IV)初始浓度、吸附时间和吸附剂用量对吸附效果的影响。结果表明,改性木质素中含有大量的酚羟基、胺基和季铵官能团,PtCl₆^2-被氨基硫脲/季铵木质素中的酚羟基还原成PtCl₄^2-后与胺基发生配合反应和氯离子发生离子交换反应,在盐酸浓度为0.5 mol·L^-1、Pt(IV)初始浓度为1 170 mg·L^-1和吸附时间为120 min的条件下,1 g·L^-1氨基硫脲/季铵木质素对Pt(IV)的饱和吸附容量为267.80 mg·g^-1,7 g·L^-1时的最大吸附率为88.50%。吸附过程遵循Freundlich模型和准二级动力学模型,表明吸附过程为单分子层非均质的化学吸附。     

新型壳聚糖季铵化改性工艺条件优化及其产品性能研究

壳聚糖的季铵盐改性物是一种重要的壳聚糖衍生物,本方法将壳聚糖(CTS)与2,3-环氧丙基三甲基氯化铵(GTA)发生醚化反应制备壳聚糖的季铵盐(HTCC),优化了制备壳聚糖季铵盐的工艺参数,确定最佳的工艺参数为:GTA与壳聚糖的质量比为4∶1,反应温度为70℃、反应时间为9h、pH=7.0时,产物取代度最高可达87.16%。将在优化的工艺条件下制备的壳聚糖季铵盐产品,用于安徽淮南的城市污水处理后,污水的浊度去除率达到98.58%。     

5-溴-3-叔丁基水杨醛的合成

以2-叔丁基苯酚、镁和多聚甲醛为原料,甲醇为溶剂,经甲酰化反应合成了3-叔丁基水杨醛,再经溴化反应合成了5-溴-3-叔丁基水杨醛.考察了溶剂、反应温度、物料比等对产品收率的影响.5-溴-3-叔丁基水杨醛合成的较优条件为:n(3-叔丁基水杨醛)∶n(液溴)=1∶1.1,反应溶剂为乙醇,反应温度60℃,反应时间8 h,产品经1H-NMR表征确认.     

HY型分子筛催化合成2,6-二甲基萘

考察了HY沸石催化2-甲基萘(2-MN)与均四甲苯(TeMB)转移甲基化合成2,6-二甲基萘(2,6-DMN)的反应条件,较适宜的反应条件是:n(2-MN):n(TeMB)=1,温度350℃,压力0.15MPa,空速4h-1.研究了负载改性的AlCl3-HY催化剂孔结构、表面酸性对2-MN与TeMB转移甲基化反应结果的影响.研究结果表明,AlCl3-HY催化剂比表面积和孔径减小,总酸量减少,LeW-is酸/Bronsted酸增加,用于催化2-MN与TeMB转移甲基化反应可以抑制三甲基萘的生成,提高2,6-DMN和β,β'-二甲基萘(β,β'-DMN)的选择性,其选择性分别达到18.5%和48.5%.     

PAMAM—COOH的合成、表征及对超细纤维合成革卫生性能的影响

分别采用盐酸和乙醛酸对0.5代聚酰胺-胺(G0.5 PAMAM)和1代聚酰胺-胺(G1 PAMAM)进行改性,得到了0.5代端羧基的树枝状大分子(G0.5PAMAM—COOH)和1.0代端羧基的树枝状大分子(G1 PAMAM—COOH)。采用单因素实验优化了乙醛酸改性G1 PAMAM的反应条件,即n(G1 PAMAM)∶n(乙醛酸)为1∶12,反应温度为35℃,反应时间为2h。采用G0.5 PAMAM—COOH和G1 PAMAM—COOH对超细纤维合成革基布进行改性,结果表明,改性后基布的透水汽性分别提高了26.97%和34.59%。SEM显示改性后基布纤维松散程度增加,孔隙变大。水接触角测试表明改性后基布上的亲水基团增多,经G0.5 PAMAM—COOH与G1 PAMMA—COOH改性的基布,其渗水时间较之未改性基布分别缩短了71.74%和78.26%,表明超细纤维合成革基布的卫生性能得到改善。     

新型聚苯胺衍生物——聚邻乙氧基苯胺的合成优化及性能研究

采用化学氧化法,以盐酸为掺杂剂合成一类新型的聚苯胺衍生物——聚邻乙氧基苯胺(POEA)。通过考察反应温度、反应时间、氧化剂用量、掺杂盐酸浓度对POEA溶解性和电性能的影响规律,优化其合成条件:在反应温度15℃,反应时间6h,盐酸摩尔浓度1.00mol/L,过硫酸铵(APS)与邻乙氧基苯胺(OEA)的质量配合比为1∶1条件下,制得的POEA的溶解度为67.52%、电导率达到0.00871S/cm,具有较好的热稳定性和电容性能,在电容电极材料领域应用前景较好。     

改性聚酰胺-胺阳离子树状大分子的合成与表征

以甲醇为溶剂、投料比为3.0GPAMAM/N,N-二甲基乙醇胺=1∶16,N,N-二甲基乙醇胺/环氧氯丙烷=1∶1、反应温度50℃、反应时间12h的优化条件下,利用环氧氯丙烷与整代产品进行加成反应,以及环氧氯丙烷与N,N-二甲基乙醇胺进行季铵化反应,对3.0GPAMAM树状大分子进行阳离子改性。并采用红外光谱(FT-IR)、核磁共振(NMR)对产品进行了结构表征。结果表明:所合成的产品与预期产物结构吻合较好,达到预期目标,且阳离子转化率达到90%以上。     

季铵盐改性蒙脱土的制备与表征

采用离子交换法将不同的季铵盐交换到蒙脱土的层间得到改性蒙脱土。以十二烷基二甲基苄基氯(1227)为例,研究了季铵盐离子交换反应的最佳反应条件为:当温度为60℃,时间为6h,1227/CEC的摩尔比为1.5∶1.0时,1227的交换率为82.65%。在相同的条件下,其它的单季铵盐的交换率也均大于80%。其中1431的交换率达到99.75%。热重分析(TG)、X-射线衍射(XRD)、红外光谱(FT-IR)的结果表明季铵盐已经插入蒙脱土的层间,且季铵盐的热稳定性明显提高。     

Insertion of triangulated surfaces into a meccano tetrahedral discretization by means of mesh refinement and optimization procedures

In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

Flow calorimeter for enthalpy increment measurements on condensed gases

A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.     

Refrigerators Enter a New Era of Health Preservation Frestech initiates the establishment of China's first standard for household sterilization refrigerators

On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.……     

A study of centrifugal cast high boron high speed steel

In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M₂(B,C), (W,Mo)₂(B,C), M₃(B,C), M₂₃(B,C)₆ type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm². The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K₁ mill housing of bar mill.     

Optimum-Simulation von Ernteprozessen

Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.