纳米碳管/聚合物功能复合材料

纳米碳管(Carbonnanotubes,CNT)具有π π共轭电子结构,可与结构相似的聚合物(Polymer)通过范德华力结合形成复合材料。导电聚合物(Electricallyconductingpolymer,ECP)包覆多壁纳米碳管(Multi walledcarbonnanotubes,MWNT)后,可用于诸如超级电容器等电子器件。共轭发光聚合物修饰纳米碳管形成的CNT polymer复合材料,具有很强的发光性能,有望用于电子接收器和光电器件。通过连结氨基聚合物,可使多壁纳米碳管溶解和功能化,从而将纳米碳管引入生物学系统中。研究结果表明,CNT polymer复合物有许多潜在的应用,有待进一步发展。     

ZnO纳米棒/CNTs复合阴极的制备及其场发射性能的研究

采用水热法和喷涂法制备ZnO纳米棒/CNTs复合材料,并测试其场发射性能。首先采用水热法在ITO电极基面生长ZnO纳米棒阵列,随后通过喷涂技术在ZnO纳米棒阵列表面沉积碳纳米管(CNTs)。使用扫描电子显微镜和X-射线衍射分别表征样品的结构和形貌特征。结果表明,经喷涂沉积的CNT薄膜均匀地包裹在ZnO纳米棒尖端。对该复合材料采用二极结构测试其场发射性能,通过测试结果发现,ZnO纳米棒/CNTs复合材料可明显改善ZnO纳米棒阵列及CNT薄膜的场发射性能,该复合材料具有低开启电场强度(约0.96V/μm),高场增强因子(9881)。因此,ZnO纳米棒/CNTs复合材料是最有前景的场发射阴极材料之一。     

纳米碳管的孔结构、相关物性和应用

评述了纳米碳管（CNT）的纳米孔隙结构及其决定的特殊物化性质,以及潜在的应用。CNT孔径体系由多层次的孔隙组合而成,开口的一维中空管腔是最基本的孔隙结构,其纳米级的尺度和物理形态决定了它的超常吸附性质和其它物化特性,使CNT成为极具潜力的纳米级能量载体;提供了进行一维物理化学过程的极限反应空间,是真正意义上的纳米反应器;CNT的比表面积和孔径结构及其决定的吸附性质还决定或者影响着许多其它物化性质（如电磁性质）。发展纳米碳管中的物理化学研究,制备基于大表面积、可控孔结构CNT的纳米器件,是CNT领域的重要研究方向。     

无机纳米ZnO或蒙脱土颗粒掺杂对低密度聚乙烯介电性能的影响

选择在低密度聚乙烯（LDPE）中掺杂无机纳米ZnO和蒙脱土（MMT）颗粒,探讨不同形态无机纳米颗粒对LDPE介电性能的影响。利用熔融共混法配合不同冷却方式制备不同结晶形态的纳米ZnO/LDPE和MMT/LDPE复合材料。通过FTIR、偏光显微镜（PLM）、SEM、DSC和热刺激电流（TSC）对试样进行表征,并。研究了纳米ZnO/LDPE和MMT/LDPE复合材料的交流击穿特性,结果表明：掺杂适当质量分数并经表面修饰的无机纳米颗粒可有效的避免其团聚现象,提高纳米ZnO/LDPE和MMT/LDPE复合材料的结晶速率,使结晶结构更完善,同时无机纳米颗粒掺杂使LDPE的陷阱密度和深度均有所增加,载流子入陷在试样内部形成界面"局域态"。经油冷却方式制备的纳米ZnO/LDPE和MMT/LDPE复合材料击穿场强比空气自然冷却分别高13.6%和14.4%,当掺杂纳米粒子质量分数为3wt%时,复合材料击穿场强出现最大值,其中纳米ZnO/LDPE复合材料比MMT/LDPE复合材料的击穿场强值高0.68%;电导率试验结果表明：纳米ZnO/LDPE复合材料电导率比MMT/LDPE复合材料低。介电性能测试表明,在1~10⁵ Hz的测试频率范围内,纳米ZnO/LDPE复合材料和MMT/LDPE复合材料介电常数降低,介质损耗角正切值有所提高。     

ZnO/BaTiO3纳米复合材料的制备及其发光性质

采用溶胶-凝胶技术制备了ZnO/BaTiO3纳复合材料，用X射线衍射仪（XRD）、透射电子显微镜（TEM）测定了不同温度处理后样品的组成、结构、形貌和尺寸。对复合材料室温下的光致发光谱分析发现，复合材料的发光强度比纯的纳米ZnO发光显著增强；纳米ZnO中氧空位引起的510nm发光带的峰位随着热处理温度的不同而分别出现蓝移和红移现象。其中蓝移主要是量子尺寸效应引起的，而红移则可能与致密化的BaTiO3所提供的高介电场有关。     

生物质炭/ZnO复合材料的制备及其吸附-光催化性能

以纳米晶纤维素（NCC）为形貌诱导模板,醋酸锌（Zn（CH₃COO）₂·2H₂O）为Zn源,采用原位聚合法制备NCC/ZnO纳米杂化物,再经550℃高温碳化,得到生物质炭/ZnO复合材料。采用TEM、XRD、BET、UV-Vis测试研究生物质炭与ZnO固体质量比（0.03:1、0.17:1、0.67:1）对生物质炭/ZnO复合材料形貌、晶体结构、孔结构及光吸收性能的影响。并进一步以亚甲基蓝（MB）为模型污染物,研究生物质炭/ZnO复合材料的吸附-光催化性能,阐明其吸附-光催化机制。结果表明,经550℃高温碳化后,NCC转化为具有石墨微晶结构的生物质炭,其骨架结构得以保留,纳米ZnO均匀负载在生物质炭表面,形成生物质炭/ZnO复合材料。与纯纳米ZnO相比,生物质炭/ZnO复合材料比表面积显著提高,具备优异的吸附性能,同时,NCC转化得到的生物质炭有效提高了ZnO的光生电子-空穴对的分离率。生物质炭/ZnO复合材料通过吸附-光催化协同效应去除水体中的MB,去除率显著增加。当生物质炭与ZnO的固体质量比为0.17:1时,生物质炭/ZnO复合材料的平均孔径为188.99 nm,比表面积为33.51 m2/g,在室温条件下,避光吸附30 min后,再使用500 W紫外灯照射20 min,即对MB降解率达到99.8%。      

双模CNT/Al复合材料变形过程的代表性体积单元模拟

目的 研究双模CNT/Al复合材料在塑性加工过程中的微观结构演变行为。方法 通过ABAQUS/Python二次开发,对双模CNT/Al复合材料代表性体积单元(RVE)进行参数化建模,并基于显式动力学求解器和欧拉-拉格朗日耦合技术,对双模CNT/Al复合材料RVE模型的单向压缩过程和挤压过程进行数值模拟分析。结果 单向压缩模拟结果显示,结构心部异质区两侧的等效塑性应变较大,结构边缘基体区域的等效塑性应变相对较小;最大等效应力位于结构边角处的基体区域,而结构心部异质区的等效应力则相对较小。通过对异质区材料和形态的影响规律进行分析发现,当异质区为粗晶材料时,其变形后的形态更趋于扁平,而当异质区为细晶材料时,其变形后的形态更接近椭圆。通过挤压过程的模拟,实现了对变形过程中双模组织结构变化的分析,模拟结果显示,材料表面与模具贴合良好,异质区随变形的进行被不断拉长,部分异质区由于拉伸程度过大,甚至出现了分离的情况。结论 提出的模拟方法为双模CNT/Al复合材料的挤压变形工艺设计和变形后组织结构预测提供了有效手段。     

原位制备季铵盐聚合物/纳米ZnO复合抗菌剂

以二甲基二烯丙基氯化铵(DMDAAC)、甲基丙烯酸(MAA)、烯丙基缩水甘油醚(AGE)、纳米ZnO为原料,通过原位法制备了聚二甲基二烯丙基氯化铵-甲基丙烯酸-烯丙基缩水甘油醚/纳米ZnO(PDMDAAC-AGE-MAA/纳米ZnO)复合材料,考察了纳米ZnO用量对复合材料性能的影响,通过FT-IR、XRD和TEM对其结构进行了表征,将其应用于棉织物整理中.结果表明:当纳米ZnO为0.8％时,PDMDAAC-AGE-MAA/纳米ZnO复合材料的稳定性最佳;复合材料中存在环氧基团以及纳米氧化锌的特征吸收峰,纳米ZnO在复合材料中具有良好的分散性;将其整理织物后,与原布相比,经10次标准洗涤织物对金黄色葡萄球菌和大肠杆菌的抗菌率高达80％以上,对白色念珠菌的抗菌性可达75％以上,具有良好的耐洗牢度;经过整理后的织物断裂强力无影响.     

微波辐照合成聚乳酸/氧化锌柱撑有机皂石纳米复合材料及其聚合动力学与结构表征

采用微波水解法制备氧化锌(ZnO)柱撑有机皂石,并以其为催化剂在微波辐照下通过D,L-丙交酯开环聚合制备聚乳酸(PLA)/ZnO柱撑有机皂石纳米复合材料。通过正交实验,获得最优聚合参数,PLA/ZnO柱撑有机皂石纳米复合材料的珨Mw为39322。聚合动力学研究表明该聚合反应为3级反应,表观速率常数为157.264mol-2·L2·s-1。通过X射线衍射、扫描电子显微镜、透射电子显微镜、差示扫描量热分析和热重分析对ZnO柱撑有机皂石、纳米ZnO和PLA/ZnO柱撑有机皂石纳米复合材料的结构进行了表征和分析,结果表明纳米ZnO柱撑有机皂石具有剥离型结构,能显著提高PLA复合材料的结晶性能和热稳定性。     

ZnO/BaTiO3纳米复合材料的制备及其发光性质

采用溶胶-凝胶技术制备了ZnO/BaTiO₃纳米复合材料,用X射线衍射仪(XRD)、透射电子显微镜(TEM)测定了不同温度处理后样品的组成、结构、形貌和尺寸.对复合材料室温下的光致发光谱分析发现,复合材料的发光强度比纯的纳米ZnO发光显著增强;纳米ZnO中氧空位引起的510nm发光带的峰位随着热处理温度的不同而分别出现蓝移和红移现象.其中蓝移主要是量子尺寸效应引起的,而红移则可能与致密化的BaTiO₃所提供的高介电场有关.     

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...     

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.     

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.     

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.……     

Synthesis of Alumina-Zirconia Nanocomposites by Solgel Process

Al₂O₃-ZrO₂ nanocomposites were developed starting with the solgel process. Composite alumina-zirconia nanopowders were synthesized from metallorganic precursors (Aluminium secondary butoxide and zirconium Iso propoxide) using the solgel process. The parameters affecting the synthesis—solvent, concentration of precursor, R/H ratio (i.e., dilution of water in solvent)—were varied as also the temperature and pH. BET and TEM were used to measure nanosize. Diffuse reflectance spectroscopy and also qualitative optical absorption led to identical particle size estimate. The variation of process parameters was used to study the effect and interdependence of process parameters. Artificial Neural Networks was used to rigorously analyze the process. Although this led to confirmation of interdependence of parameters, the presence of a single overwhelming solvent variable was also established. Then the optimal process was used to synthesize more nanopowder. To produce bulk nanocomposite the nanopowders were sintered by varying the temperature and time period. The sintered lithoids were probed with a vickers hardness tester to measure elastic modulus, hardness, and fracture toughness. The results showed high elastic modulus, modest hardness, and very high fracture toughness.     

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.     

Analysis of marine hydrobiont lipid extracts as possible cryoprotective agents

We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.     

Low-Temperature Properties of Silver

Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.     

Early ironwork in Biscay: Survey,excavation, experimentation and materials characterization. An integral study of the mountainside ironworks (ferrerías de monte or “haizeolak”)

ABSTRACT

The production of iron in Biscay (Basque Country, Spain) has been a hallmark of this territory of the North of the Iberian Peninsula throughout its history. The Archaeology team of the Basque Country Mining Museum has spent 13 years, so far, studying the origins of this activity through the evidences left at the old pre-hydraulic iron production workshops known as mountainside ironworks (ferrerías de monte) or haizeolak. It has catalogued 170 archaeometallurgical sites of this type in Biscay, and the archeological excavation of some of them has led to the knowledge of the different stages of the production process that took place in these workshops. The team has also experimentally reproduced the work carried out in a mountainside ironworks from the High Middle Ages, and it has currently started the characterization process of this type of activity through the study of the collected materials.