含二氮杂萘酮结构聚芳酯的合成及其在绝缘漆中的应用

以二酸4-[4-(4-羧基苯氧基)苯基]-2-(4-羧基苯基)二氮杂萘-1-酮(Ⅰ)与4,4'二羟基二苯丙烷进行溶液缩聚反应合成了一种含有二氮杂萘酮结构的聚芳酯,采用FT-IR,1H NMR对其结构进行了表征,利用差示扫描量热仪(DSC),热重分析仪(TGA)研究了聚芳酯的热性能.结果表明所合成的聚芳酯具有高的玻璃化转变温度(227℃),在氮气气氛中5%的热失重温度高于455℃.聚芳酯可溶解于N-甲基吡咯烷酮(NMP),N,N-二甲基乙酰胺(DMAc),氯仿等多种溶剂,该类聚芳酯制成的绝缘漆,具有机械强度高,柔韧性和附着力好,以及良好的电绝缘性能.     

含1-(萘-1-磺酰基)萘结构聚芳醚的合成及表征

以氯苯、α-氯代萘、氯磺酸、二氯亚砜为原料,合成了4-氯-1-萘磺酰氯,经Frield-Craft磺酰基化反应,合成了含两个1,4-萘结构的4-氯-1-(4′-氯-1-萘磺酰基)萘(CCNSN)。CCNSN分别与双酚A、酚酞、对苯二酚及4-(4-羟基苯基)-2,3-二氮杂萘-1-酮经溶液亲核取代逐步聚合反应,合成了4种含1-(萘-1-磺酰基)萘结构的聚芳醚(Pa~Pd)。用NMR、FT-IR对单体和聚合物进行了表征,证明其结构正确;用DSC、TGA和WAXD等方法对聚合物的热性能及结晶性进行了表征,结果表明,聚合物的玻璃化转变温度在226℃~318℃之间,氮气环境下,5%热失重的起始温度均在450℃以上,说明具有良好的热稳定性;考察了聚合物的溶解性能,除Pc不溶于常见的有机溶剂外,Pa、Pb、Pd皆可溶于氯仿(CHCl3)、1,1,2,2-四氯乙烷(TCE)和N,N-二甲基乙酰胺(DMAC)、N-甲基吡咯烷酮(NMP)等非质子极性溶剂。     

含氮杂环结构溶致液晶聚芳酰胺的合成和性能

将二胺1,2-二氢-2-(4-氨基苯基)-4-[4-(4氨基苯氧基)-苯基]-二氮杂萘-1-酮和对苯二胺与对苯二甲酰氯进行低温溶液缩聚反应并改变两种二胺的比例,制备出一系列共聚酰胺树脂.结果表明,共聚酰胺树脂的特性粘度为1.76-3.29 dL/g;随着主链中二氮杂萘酮结构比例的增加,聚合物的溶解性逐渐得到改善;该类聚合物具有较高的玻璃化转化温度(312～351 ℃);在氮气气氛中10%热失重温度为513～534 ℃;聚合物呈现无定型的状态,并且可以在浓硫酸、N-甲基吡咯烷酮/氯化锂、N,N-二甲基乙酰胺/氯化锂中呈现溶致液晶织构.     

新型可溶性聚芳醚腈酮的合成及其在绝缘漆领域的应用

以4种含杂萘联苯结构的类双酚单体分别与2,6-二氯苯腈、4,4-二氟酮进行亲核缩聚反应,制备了一系列新型含杂萘联苯结构的聚芳醚腈酮树脂.研究了不同类双酚单体结构对聚合物性能的影响.所制备聚合物均具有较高的分子量,特性粘度在0.50dL/g以上,可溶解于N-甲基吡咯烷酮(NMP),N,N-二甲基乙酰胺(DMAc),氯仿等极性非质子型有机溶剂中.聚合物的结构以FT-IR进行表征;利用差示扫描量热仪(DSC)和热重分析仪(TGA)研究了聚合物的耐热性能,结果表明,该类聚芳醚腈酮树脂具有优异的耐热性能,玻璃化转变温度(Tg)在255～277℃之间,10%热失重温度(Td)在498℃以上.由该系列聚芳醚腈酮材料制成的绝缘漆具有良好的电绝缘性能,较高的机械强度,良好的柔韧性和附着力.     

杂萘联苯结构可交联聚芳醚腈的合成与表征

以4-(4-羟基苯基)-2,3-二氮杂萘-1-酮(DHPZ)、4-(3-烯丙基-4-羟基苯基)-2,3-二氮杂萘-1-酮(allyl-DHPZ)和2,6-二氟苯腈(DFBN)为单体,采用芳香亲核取代法,通过改变单体的物质的量配比,合成了系列可溶解可交联的聚芳醚腈(PAENs)。通过核磁共振测试证明了所合成的单体以及聚合物的结构,凝胶渗透色谱仪测定了聚合物的相对分子质量(珚Mw为45130~58403),红外光谱和差示扫描量热仪分析了聚合物的热交联反应过程。所合成的聚芳醚腈在室温时可溶于氯仿、二甲基乙酰胺、二甲基甲酰胺和甲基吡咯烷酮等极性有机溶剂,交联后的聚合物不溶于任何有机溶剂(凝胶含量最高达到98.6%),具有良好的热稳定性能(1%热失重为450℃)。     

新型杂环氯代聚芳醚的合成与性能

以自制的新型氯代类双酚化合物4-(3-氯-4-羟基苯基）-2,3-二氮杂萘-1-酮（OC-HPPZ）为单体,分别与4,4/-二氟二苯酮、4,4/-二氯二苯砚和1,4-双-（4-氯代苯甲酰基）苯进行缩聚反应,合成了一类新型的具有较高分子质量的聚芳醚材料。利用FTIR、1H NMR等分析手段研究了类双酚化合物OC-HPPZ及其聚合物的结构;采用差示扫描量热仪（DSC）、热重分析仪（TGA）研究了聚合物的耐热性能,结果表明,新型聚芳醚砜、聚芳醚酮和聚芳醚酮酮具有优异的耐热性能和热稳定性能,其玻璃化转变温度为234～287℃,在氮气氛中5%热失重温度均高于420℃,新型氯代聚芳醚在氯仿、N、N-二甲基乙酰胺等极性有机溶剂中可溶解并浇铸得到透明、韧性的薄膜。     

甲基取代杂萘联苯型聚芳醚的合成、表征及性能

以自制的新型甲基取代类双酚 4 - ( 3-甲基 - 4 -羟基苯基 ) - 2 - 3-二氮杂萘 - 1-酮 ( OM- HPPZ)为单体与4 ,4′-二氟二苯酮、4 ,4′-二氯二苯砜进行亲核缩聚反应 ,制得了一类新型甲基取代聚芳醚酮、聚芳醚砜及其共聚物聚芳醚砜酮树脂。在适宜的聚合条件下 ,获得了高分子量的聚合物 ,聚醚酮的特性粘度可达0 .70× 10 2 m L/ g;通过调节砜酮比例 ( S/ K)可获得不同分子量、不同玻璃化温度的共聚物 ( PPESK)。利用 DSC、TGA研究了聚合物的耐热性能 ,结果表明 ,新型聚芳醚玻璃化温度高 ( 2 5 2℃～ 2 90℃ ) ,耐热稳定性好 ( 5 %热失重温度高于 4 16℃ ) ,在氯仿、DMAc等极性有机溶剂中可溶解成膜 ,以 FT- IR和 1H-NMR研究了类双酚单体 OM- HPPZ和聚合物的结构 ,证明与设计结构完全一致     

含氟-吡啶环聚酰亚胺的合成与性能

用4-苯基-2,6-双[3-(4-氨基-2-三氟甲基苯氧基)苯基]吡啶(m,p-6FPAPP)作为二胺,3,3′,4,4′-二苯酮四甲酸二酐(BTDA)及2,2-双[4-(3,4-二羧基苯氧基)苯基]丙烷二酐(BPADA)作为二酐,以N,N-二甲基甲酰胺(DMF)为溶剂,通过常规的两步法,合成了可溶性含氟聚酰亚胺。用FT-IR、DSC、TGA、UV-vis、溶解性和吸水率测试对聚合物的结构和性能进行了表征。结果表明,FT-IR测试在1780 cm-1、1720 cm-1和1380 cm-1左右出现了聚酰亚胺的特征吸收峰。所得聚酰亚胺在常见溶剂(如间甲酚,DMF,N,N-二甲基乙酰胺(DMAc),二甲基亚砜(DMSO),N-甲基吡咯烷酮(NMP),四氢呋喃(THF))中可溶解;在氮气氛中,玻璃化转变温度(Tg)为202.1℃~219.7℃,10%失重温度为537.0℃~572.8℃,800℃质量保持率为60.7%~63.1%。PI膜的紫外截止波长为375 nm~380 nm,吸水率为0.55%~0.63%。     

含间甲基取代新型聚芳酰胺的合成和性能

以一种含间甲基取代新型杂萘联苯结构的芳香二胺:2-(4-氨基苯基)-4-[2-甲基-4-(4-氨基苯氧基)]-2,3-二氮杂萘-1-酮(MM-DA)为单体,制备出一类新型的杂萘联苯型聚芳酰胺,以FT-IR、1H-NMR证明了它的聚合物结构, 其特性粘度为1．72-2．08 dL．g-1,玻璃化转变温度为315-337℃,在氮气气氛中5％热失重温度高于440℃．聚芳酰胺在 DMAc、NMP等极性非质子溶剂中有良好的溶解性．聚芳酰胺膜的拉伸强度为81-99 MPa,断裂伸长率为11．4％-20．8％, 拉伸模量为1．91-2．34 GPa．扭曲非共平面结构的存在使该系列聚芳酰胺耐高温、具有良好的溶解性能和力学性能．     

聚芳醚砜醚酮共聚物的合成与表征

通过低温溶液亲电共缩聚合成了聚芳醚醚酮醚砜醚酮(Ia)、聚芳醚酮酮醚砜醚酮(Ib),甲基取代、双邻位甲基取代的聚芳醚酮酮醚酮醚砜醚酮(Ic、Id)等4种结构新型的共聚物。用傅里叶红外光谱仪(FT-IR)、核磁共振(1H-NMR)、差示扫描量热仪(DSC)、热重分析(TGA)、X射线衍射仪(WAXD)对聚合物进行了结构表征和性能测试。结果表明,共聚物有较高的玻璃化转变温度(Tg)177℃~188℃;较高的热分解温度(Td5%≥460℃),共聚物能溶解于N-甲基-2-吡咯烷酮,四氯乙烷和浓硫酸中;甲基取代的共聚物溶解性得到了明显改善,室温下还能溶于二氯甲烷、二氯乙烷、氯仿、N,N-二甲基甲酰胺、N,N-二甲基乙酰胺中。     

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.……     

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.     

Thixotropy of Systems with Shear Thinning and Plastic Flow Behavior

The definition of the thixotropy is a decrease in viscosity with time in shear and a subsequent recovery of viscosity after the shear deformation is removed.We ...     

Brainstorming for ISO Strategy 2016-2020

正Responding to ISO’s appeal for survey for the to-be-developed ISO Strategy Plan for 2016-2020,SAC hosted a special workshop over the needs and comments of various fi elds on June 8 in Beijing.The workshop was attended by ISO President-elect and Ansteel General Manager Zhang Xiaogang,SAC Vice-Administrator Yu Xinli,and 30 experts from     

CNAS Passes APLAC's PTP Review

正The review group of Asia Pacific Laboratory Accreditation Cooperation(APLAC)carried out a 4-day peer review of the proficiency testing provider(PTP)for China National Accreditation Service for Conformity Assessment(CNAS)from July 28 to 31,2014.CNAS passed the PTP review with excellent performance.Two senior peer reviewers of APLAC made a comprehensive,rigorous and detailed review of CNAS’s PTP accreditation activities,and made the on-spot inspection of the review groups in Shanghai and Shenzhen respectively.