新型共缩聚杂萘联苯聚芳酰胺的合成与性能研究

采用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(A)、4,4'-二氨基二苯醚(B)、对苯二胺(C)共同作为共缩聚二胺单体,与对苯二甲酸采用Yamazaki膦酰化法,成功得到高分子量的共聚酰胺树脂,其特性粘度为0.79～2.10dL/g;以FT-IR表征了聚合物的结构;利用DSC、TGA研究了聚合物的耐热性能,结果表明该系列聚合物具有高的玻璃化转变温度(约300℃),氮气气氛中5%热失重温度在480℃以上,同时研究了聚合物的力学性能以及A在二胺单体中所占比例与聚合物溶解性的关系.部分聚合物可在N-甲基吡咯烷酮中溶解并浇注得到韧性薄膜.偏光显微镜观察表明大部分聚合物在一些极性溶剂中呈现溶致液晶织构.     

DHPZ-DA/DAPE/PPD/NDA杂萘聚芳酰胺的合成及性能

由自制二胺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(DHPZ-DA)、4,4‘-二氨基二苯醚(DAPE)和对苯二胺(PPD)与2,6-萘二酸(NDA)进行共缩聚反应,改变不同二胺的配比,所得聚芳酰胺树脂特征粘度为0.24 dL/g～2.78 dL/g ;以FT-IR、1H-NMR手段分析了聚合物的结构;用DSC、TGA手段研究了聚合物的耐热性能.结果表明,该类聚合物具有较高的玻璃化转变温度(280 ℃以上);氮气气氛中5%热失重温度在450 ℃以上;当DHPZ-DA DAPE在二胺中比例达70%时能溶于NMP中,当DHPZ-DA DAPE含量达80%时能溶于DMAc、DMF等非质子极性溶剂中.     

含二氮杂萘酮联苯结构新型聚芳酰胺的合成及性能研究

以一种甲氧基取代的新型含杂萘联苯结构的芳香二胺:2-(4-氨基苯基)-4-[3-甲氧基-4-(4-氨基苯氧基)苯基]-2,3-二氮杂萘-1-酮(OO-DA)为单体,采用Yamazaki体系,分别和3种芳香二酸进行溶液亲核缩聚反应,制得一类新型杂萘联苯型聚芳酰胺树脂,其特性粘度为0.89~1.03dL/g;以FT-IR1、H-NMR表征了聚合物的结构;利用DSC、TGA研究了聚合物的热性能,结果表明聚芳酰胺的玻璃化转变温度为281~307℃,氮气氛中5%热失重温度达440℃以上,800℃时残留质量>55%;在DMAC、NMP等极性非质子性溶剂中有良好的溶解性,所得聚酰胺膜的拉伸强度为69~93MPa,断裂伸长率8.65%~9.47%,拉伸模量1.49~1.78GPa,体积电阻率>1015Ω.cm。     

含醚键双二氮杂萘酮结构聚芳醚腈砜的合成与性能

文中以含醚键双二氮杂萘酮结构化合物4,4’-双(氧基(1,4-苯撑))-双二氮杂萘-1(2H)酮-二苯醚(OBDHPZ)为类双酚单体,与4,4’-二氟二苯砜(DFS)和2,6’-二氟苯腈(DFBN)进行高温溶液缩聚反应,通过调节聚合物分子主链中砜基和氰基等的含量,合成了一系列不同腈砜比的含醚键双二氮杂萘酮联苯结构聚芳醚腈砜树脂(PBPENS),其N-甲基吡咯烷酮(NMP)溶液在25℃的特性黏度为0.63～0.90 dL/g。通过红外光谱、核磁共振氢谱和广角X射线衍射仪表征了所合成聚芳醚腈砜的结构;通过差示扫描量热仪和热失重分析仪分析了该类聚芳醚腈砜的热性能,聚合物的玻璃化转变温度(T_g)在322～325℃,5%热失重温度(T_d5%)在485～500℃。该类聚合物在常温时可溶解于NMP、N,N-二甲基乙酰胺(DMAc)、氯仿等极性非质子有机溶剂;采用溶液浇筑法制备了含醚键双二氮杂萘酮结构聚芳醚腈砜薄膜,薄膜的拉伸强度可以达到56～65 MPa。     

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     

含二氮杂萘酮联苯结构聚芳酯的合成和性能

以新二酸4-[4-(4-羧基苯氧基)苯基]-2-(4-羧基苯基)二氮杂萘-1-酮(1)和4种商品二酚进行溶液缩聚反应,制备出一系列古杂萘联苯结构新型聚芳酯,其特性粘度在0．50-0．58 dL·g-1之间．以FT-IR．1H-NMR证明了聚合物的结构．该类聚芳醇的玻璃化转变温度在209-272℃之间,在N2气氛下10％的热失重温度在468-481℃之间．聚芳本具有无定型结构,可溶解于N-甲基吡咯烷酮(NMP),N,N-二甲基乙酰胺(DMAc),间甲酚,吡啶和氯仿(CHCls)中．扭曲和非共平面的结构存在使该系列聚芳酯既耐高温又具有良好的溶解性能．     

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．     

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.     

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.     

含间甲基取代杂萘联苯结构共聚芳酰胺的合成与性能

以新型的含间甲基取代杂萘联苯结构的二胺2-(4氨-基苯基)-4-[2甲-基-4-(4氨-基苯氧基)]-2,3-二氮杂萘-1-酮为单体,与2,6萘-二甲酸经溶液缩聚反应制备新型聚芳酰胺,以4,4二-苯醚二羧酸(OBBA)为第三单体对聚芳酰胺进行共缩聚改性,并研究了OBBA的含量及结构对聚芳酰胺性能的影响。当OBBA与NDA的摩尔配比为4∶6时共聚物黏度最大为1.82 dL/g。系列聚芳酰胺具有良好的溶解性,可溶于NM P、DM A c等极性非质子溶剂,玻璃化转变温度高于310℃,5%热失重温度大于445℃。     

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.……     

From Industry 4.0 to Research 4.0. Development of High Performance Fibers in the Light of Digitization

We associate a variety of innovations with the term ＂Industry 4.0＂. The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di...     

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.……     

Roman iron and steel: A review

ABSTRACT

The production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them.     

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.     

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