镍铁纤维的形态结构及性能研究

采用圆铜管包覆拉拔镍铁合金丝后经电解化学处理制备出了单丝长度38～40mm,直径约10μm吸波镍铁纤维束丝。采用扫描电镜、X射线衍射、振动样品磁强计(VSM)及纺织纤维性能测试仪器对纤维的形貌、组分、磁性能及可纺性能进行了表征分析。实验结果表明此镍铁纤维截面呈不规则异形,纵向光滑有多道沟槽、无卷曲,长径比达3800以上,此结构有利于增强其可纺性能和吸波性能。纤维镍、铁总含量高达90%以上,比饱和磁化强度达63.45A.m2/kg,初始磁导率达2035H/m,远高于常规铁氧体吸波材料;其拉伸、弯曲、摩擦等可纺性能与不锈钢纤维、棉纤维做了对比,预测了镍铁纤维可用于纺织加工开发柔性吸波织物。     

不锈钢纤维织物电磁屏蔽效能的研究现状

不锈钢纤维织物具有电磁屏蔽效能良好及防辐射效果持久、透气性好、穿着舒适、加工方便等特点,是当今世界上应用最广泛的高效屏蔽织物.简要描述了不锈钢纤维混纺纱线、不锈钢纤维织物的制备方法及其产品开发现状,重点阐述了不锈钢纤维特性、纱线结构、织物结构及电磁波频率等因素对不锈钢纤维织物电磁屏蔽效能的影响规律.此外,还指出对电磁波屏蔽机理的探索和产品的开发是该材料领域今后的研究重点.     

远红外磁性纤维的研究

对远红外磁性纤维进行了力学、拉伸性能及其磁性能等的研究，结果发现，随着拉伸倍数的提高，纤维的强度增加；随着磁粉含量的增加，纤维的力学性能降低，聚合物组分的结晶度、熔融温度降低，磁性能增加；随着纤维样品厚度的增加，磁性能也增大。远红外磁性纤维具有较高的远红外线发射率，可达到86％(100℃)左右。用该种纤维织物改善血流动力学较单纯远红外纤维织物有明显提高。     

不锈钢纤维混纺织物微波反射性能研究

对不同掺量比例的不锈钢纤维/涤棉、不同入射角度和厚度的织物进行了微波反射性能测试研究,结果表明,在5%～30%(质量分数)不锈钢纤维掺量中,随着不锈钢纤维含量增加,织物的微波反射率呈现先增大后减小的趋势,当不锈钢纤维含量为20%(质量分数)时反射率达到最大。并对影响微波反射特性相关因素进行了分析探讨。     

静电纺丝法制备MWNTs／聚胺醚复合纳米纤维

摘要用静电纺丝法制备MWNTs／聚胺醚复合纳米纤维，将收集到的无纺布通过SEM观察其微观形貌，并用Image-ProPlus6．0软件测量纤维的直径；分别用TG和XRD测试了复合纤维的热性能和结晶行为。结果表明，MWNTs含量较多的纺丝溶液受到的电场力较大，比较容易得到纤维，且得到的纤维直径较细；MWNTs含量为l％时...     

纺织品设计中遗传算法的应用

近年来，保健纺织品中的功能纤维受经济发展影响，其应用有了更广阔的领域。磁性纤维织物以丙纶纤维为集体，采用共混纺丝法制成，在医疗、防护、屏蔽及生物技术中得到了广泛的应用。但丙纶磁性纤维的静电、透气等方面较差，因此此类纺织品舒适性能降低。为此，对其进行优化和设计有利于改变上述现状。本文则以纺织品混纺比的优化和设计为切入点，通过应用遗传算法确定纺织品的整体功能，从而得出最优化混纺比方案，尽可能弥补传统纺织品设计的随意性和片面性。     

单宁/醋酸复合纳米纤维的制备及抗菌性研究

利用静电纺丝技术制备了质量分数为11％的醋酸纳米纤维以及单宁（TA）质量分数为1％、3X、5％的单宁／醋酸复合纳米纤维膜；采用扫描电镜和傅里叶红外光谱进行了形貌表征和成分分析，用改良的振荡烧瓶法测试了纳米膜的抗菌性能。结果表明：在试验范围内均能制得连续均匀、表面光滑的纳米级纤维；TA的添加对纤维形态有影响，随着添加量的...     

土埋条件下生物基锦纶56与锦纶6纤维的老化行为

为探究生物基锦纶56与锦纶6纤维在土壤填埋条件下是否会发生老化甚至降解，研究了土壤填埋时间、水分输入量和活性污泥含量对织物性能的影响。结果表明，在室温、不含活性污泥的土壤中填埋老化40周后，生物基锦纶56织物降强率小于15%；在室温、含50%活性污泥和0.5 L/d水分输入量的条件下，生物基锦纶56织物在土埋16周后强力下降约35%，进一步增加土埋时间(到40周)、活性污泥含量和输水量，织物强力不再降低。老化后纤维表面出现明显的刻蚀和凹陷，结晶度增加了3%～6%，表明老化过程主要发生在纤维的无定形区。石油基锦纶6织物在相同实验条件下，强力下降均低于9%，表明生物基锦纶56纤维更容易在土埋条件下发生老化现象。     

兰州化物所研发改善纤维织物复合材料摩擦性能新方法

<正>聚四氟乙烯/芳纶纤维(PTFE/Nomex)混纺织物具有自润滑性、高强度,且应用范围广等特点。然而,芳纶纤维和聚四氟乙烯纤维的表面惰性及较小的粗糙度阻碍了织物和粘结树脂之间的有效粘结,从而影响了聚四氟乙烯/芳纶纤维混纺织物-聚合物基复合材料的抗磨损性能。填充剂填充和织物表面改性是改进织物复合材料摩擦性能的常用方法。但是,将润滑剂加入聚合物基体,在减少     

粉末涂料在纺织印染中的应用

粉末涂料不是以水或溶剂为分散介质，而是借助于空气为分散介质。因此，基本上无三废、 无公害、节能、使用安全、利用率高，并可获得与液态涂料使用性能相当的效果。1 应 用涂料对纤维没有亲和力，它溶于介质中，完全借助于高分子粘合剂与纤维粘合在一起，经高 温焙烘后，粘合剂在织物表面形成具有一定弹性的耐磨性透明树脂薄膜，薄膜层中的涂料粒 子粘附在纤维上。涂料可用于织物的染色，例如，棉／维混纺细布具有坚牢、透气性好、舒适保暖、价格便宜 等优良特点，但棉／维织物缺点是色泽欠佳，抗皱性和易染性差，在上色后有银丝夹花现象 …     

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 ...     

Effect of Oxide Assisted Metal Nanoparticles on Microstructure and Morphology of Gallium oxide Nanowires

Several researches have been reported about the characteristic of β-Ga2O3 nanowires which was synthesized on nickel oxide particle. But indeed, recent researches about synthesis of β-Ga2O3 nanowires on oxide-assisted transition metal are limited to nickel or cobalt oxide catalyst. In this work, Gallium oxide (β-Ga2O3 ) nanowires were synthesized by a simple thermal evaporation method from gallium powder in the range of 700 - 1000℃ using the iron, nickel, copper, cobalt and zinc oxide as a catalyst, respectively. The β-Ga2O3 nanowires with single crystalline without defects were successfully synthesized at the reaction temperature of 850, 900 and 950℃ in all the catalysts. But optimum experimental condition in synthesis of nanowires varied with the kind of catalyst. As increasing synthesis temperature,the morphology of gallium oxide nanowires changed from nanowires to nanorods, and its diameter increased. From these results, we could be proposed that the growth mechanism of β-Ga2O3 nanowires was changed with synthesis temperature of nanowires. Microstructure and morphology of Synthesized nanowire was characterized by HR-TEM, FE-SEM, EDX and XRD.     

The Influence of Nitrogen and Boron Implant into Silicon Substrate on the Phase and Internal Stress of c-BN Films

Cubic boron nitride(c-BN) film was deposited on a Si (100) substrate by the RF-magnetron sputtering.The mainly problems for fabrication of c-BN films are the low purity and high intrinsic compressive stress. In order to solve the two problems, the c-BN film with the buffer interlayer was deposited on the substrate which had been implanted with nitrogen and/or boron ions. The results show: the implantation of nitrogen ions can obviously increase c-BN content and reduce the internal stress slightly; while the implantation of boron shows no obvious improvement to the content of c-BN, which can reduce the internal stress in the film obviously. In addition, it is suggested that the implantation of nitrogen and boron shows the best result, which not only can increase the content of c-BN, but also reduce the internal stress in the c-BN film obviously.