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。     

无水型双(全氟丁基磺酰)亚胺锂的合成与表征

以全氟丁基磺酰氟为原料,经胺化、成盐、中和、置换反应合成了无水型双(全氟丁基磺酰)亚胺锂。优化了双(全氟丁基磺酰)亚胺三乙胺盐的合成条件。较优的条件为:n(C4F9SO2NH2)∶n(C4F9SO2F):n(NEt3)=1:1.04:1.4,反应温度80℃,反应时间42h。在该条件下,反应收率可达99%以上,合成双(全氟丁基磺酰)亚胺锂的总收率为53.3%。通过FT-IR、1 H-NMR、MS和ICP等对中间体及最终产物进行了表征。     

N,N′-二己基对苯二胺的合成

以对苯二胺为起始反应物,利用取代N-烷基化方法,与1-溴己烷进行直接烷基化反应,通过元素分析和光谱分析,证实了合成产物为N,N′-二己基对苯二胺,反应产物收率大于60%,单N-己基化选择性达到100%。     

氟碳丙烯酸酯对聚丙烯酰胺的改性

用N-丙基,N-羟乙基全氟辛基磺酰胺(FC)与丙烯酸反应得到了N-丙基,N-羟乙基全氟辛基磺酰胺丙烯酸酯(FCA),再通过与丙烯酰胺共聚得了氟碳改性聚丙烯酰胺P(AM—FCA)。考察了共聚物中FCA单体含量、溶液温度、盐浓度、P(AM—FCA)质量分数对溶液粘度的影响．结果表明．在实验范围内．共聚物溶液的表现粘度随P(AM—FCA)质量分数和盐浓度的增加而增加,随溶液温度和FCA单体含量的增加出现极值,共聚物和聚丙烯酰胺相比,具有良好抗温、耐盐性能,可望作为三次采油用驱油荆。     

一种新型的聚酰胺预聚物——对二甲酰氯基二苯氧基乙烷/丁烷的合成

以对羟基苯甲酸和1,2-二溴乙烷或1,4-二溴丁烷为原料,以无水N,N-二甲基乙酰胺为溶剂,在回流温度下,反应30min制得对二羧基二苯氧基乙烷/丁烷,收率:76.4 %,纯度:99.5%;再通过二氯亚砜进行酰氯化4h,最后得到了目标化合物,收率:89.32%,纯度:98.9%.这是一种新型的聚酰胺预聚物.反应产物的结构分别用元素分析、IR、1HNMR进行了表征.该路线反应时间短,产品的总收率高,纯度高.     

4-马来酰亚胺基取代邻苯二甲酰亚胺的合成研究

以4-氨基邻苯二甲酰亚胺和马来酸酐为原料,分别采用两步法和一步法合成了4-马来酰亚胺基取代邻苯二甲酰亚胺,探索了两种合成方法的最佳工艺条件,并通过红外光谱(FT-IR)、核磁共振氢谱(~1 H-NMR)对中间产物和目标产物进行了结构表征。分别采用两步法和一步法合成了4-马来酰亚胺基取代邻苯二甲酰亚胺,并对两种合成方法的工艺条件进行了优化。实验结果表明:采用一步法合成4-马来酰亚胺基取代邻苯二甲酰亚胺的最佳工艺条件为:甲苯与N,N-二甲基甲酰胺(DMF)为共溶剂的体积配比为1∶1,4-氨基邻苯二甲酰亚胺用量0.005mol,马来酸酐用量0.006mol,快速加热到120℃下反应,制得的4-马来酰亚胺基取代邻苯二甲酰亚胺的产率可达60.3%。由于一步法可对反应溶剂甲苯进行回收,相比两步法生产成本低。     

PBAMO-GAP-PBAMO三嵌段共聚物的制备及表征EI北大核心CSCD

以三氟化硼四氢呋喃络合物(BF_3·THF)为催化剂,用端羟基聚环氧氯丙烷(PECH)大分子引发3,3-双氯甲基氧杂环丁烷(BCMO)开环聚合得到三嵌段共聚醚,再经过叠氮化反应得到聚3,3-双叠氮甲基氧杂环丁烷-聚叠氮缩水甘油醚-聚3,3-双叠氮甲基氧杂环丁烷(PBAMO-GAP-PBAMO)三嵌段共聚物。采用红外光谱、核磁共振碳谱、凝胶渗透色谱和差示扫描量热分析等对产物的结构和性能进行了测试和表征。对聚合反应和叠氮化反应的条件进行了研究,结果表明,聚合反应时间为8 h、PECH与BCMO的质量比为1∶2,并以N,N-二甲基乙酰胺作叠氮化反应溶剂时,得到的聚合产物相对分子质量可达6242,叠氮取代率达98.2%;产物的玻璃化转变温度为-46.1℃,热分解温度为235. 1℃。     

PBAMO-GAP-PBAMO三嵌段共聚物的制备及表征

以三氟化硼四氢呋喃络合物(BF_3·THF)为催化剂,用端羟基聚环氧氯丙烷(PECH)大分子引发3,3-双氯甲基氧杂环丁烷(BCMO)开环聚合得到三嵌段共聚醚,再经过叠氮化反应得到聚3,3-双叠氮甲基氧杂环丁烷-聚叠氮缩水甘油醚-聚3,3-双叠氮甲基氧杂环丁烷(PBAMO-GAP-PBAMO)三嵌段共聚物。采用红外光谱、核磁共振碳谱、凝胶渗透色谱和差示扫描量热分析等对产物的结构和性能进行了测试和表征。对聚合反应和叠氮化反应的条件进行了研究,结果表明,聚合反应时间为8 h、PECH与BCMO的质量比为1∶2,并以N,N-二甲基乙酰胺作叠氮化反应溶剂时,得到的聚合产物相对分子质量可达6242,叠氮取代率达98.2%;产物的玻璃化转变温度为-46.1℃,热分解温度为235. 1℃。     

形状记忆聚氨酯丙烯酸酯的制备及性能

先以二元醇(1,4-丁二醇(BDO))引发ε-己内酯(ε-CL)开环聚合得到不同相对分子质量的4种聚己内酯二醇软段,再与六亚甲基二异氰酸酯(HDI)和甲基丙烯酸羟乙酯(HEMA)反应得到聚氨酯丙烯酸酯(PUA)。其中多元醇、二异氰酸酯和甲基丙烯酸羟乙酯的摩尔比为1∶2∶2。将制得的PUA溶于N,N-二甲基甲酰胺制备60%的溶液,加入光引发剂后紫外光固化制得聚氨酯丙烯酸酯薄膜。用傅里叶变换红外光谱、核磁和凝胶渗透色谱进行聚氨酯丙烯酸酯的结构和组成表征,通过差示扫描量热法、热失重分析、动态力学热分析(DMA)、力学性能测试等对PUA薄膜进行性能分析。并使用DMA的应力控制模式表征其形状记忆效应,发现当软段相对分子质量超过2000时,PUA膜具有极好的形状固定率和回复率,均高达98%以上,具有良好的重复性能。     

N,N-二-2,3-环氧丙基月桂胺的合成工艺研究

通过将月桂胺(DA)与环氧氯丙烷发生开环反应所得的氯醇分子进一步在KOH-H2O溶液中进行闭环反应,制备得到具有良好反应活性的表面活性剂中间体N,N-二-2,3-环氧丙基月桂胺(EDA)。采用FTIR,1 H-NMR,13 C-NMR等表征手段对产物的结构进行了表征。研究了闭环反应温度、碱的用量、环氧氯丙烷的用量、碱的种类和闭环反应时间等反应条件对产物中EDA含量的影响,在此基础上确定了N,N-二-2,3-环氧丙基月桂胺的最优化反应条件。     

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.     

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.……     

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.     

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.……     

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.     

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.     

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.