高速钢表面PN＋PVD复合处理工艺和性能研究

采用多弧离子镀设备,在高速钢W18Cr4V上先进行等离子氮化,再沉积TiN薄膜,研究了不同渗氮温度和时间对PN＋TiN薄膜组织和性能的影响。结果表明,温度为500℃左右和时间为2h以上条件下对W18Cr4V进行渗氮处理后再沉积TiN薄膜,可以得到最佳的薄膜表面显微硬度（1800～2000HV0.05）和膜／基结合力（50N）,涂层耐磨性也得到明显提高。     

儿茶素在离子交换纤维上的扩散机理研究

研究了静态下儿茶素在自制的聚丙烯基阴离子交换纤维上的扩散机理。结果表明，离子交换纤维对儿茶素的吸附主要以扩散而不是以交换为主控步骤．在反应的初期．以液膜扩散为主，反应3min后．以孔隙扩散控制为主。     

离子交换树脂吸附TP5的热力学和动力学研究

针对凝胶型阳离子交换树脂对TP5的吸附行为,研究了间歇反应中TP5水溶液的吸附热力学与动力学特性。热力学研究表明,TP5在所用树脂上的吸附平衡数据符合Langmu ir吸附等温方程。在283.15~303.15 K之间,TP5的质量浓度在10 g/L时,离子交换树脂对TP5的吸附过程可分两个阶段,第一阶段受液膜扩散控制,第二阶段主要吸附过程受颗粒扩散的控制。利用TP5在不同条件下的动态吸附性能实验,考察了pH值、温度、溶液初始浓度、搅拌转速等因素的影响。采用两相阻力模型描述了TP5在离子交换介质中的动态吸附性能,通过计算得到了TP5在吸附剂颗粒中的颗粒扩散系数,有助于进一步研究小肽在吸附过程中的传质现象。     

Magnetic Behavior of Trinuclear Vanadium(II)–Diamine Complexes. Part 2. Large Intramolecular Antiferromagnetic Exchange Interactions in a Triangular Unit

This study reports the magnetic structures of newly reported trinuclear vanadium(II)–diamine complexes. Using the isotropic Heisenberg exchange Hamiltonian, it is suggested that there are strong intramolecular antiferromagnetic interactions among the vanadium(II) ions. It is also suggested that these complexes are good candidates to the geometrically frustrated systems. For part 1 see A. Bayri, J. Inorg. Organomet. Polym. Mater., (in press) An erratum to this article can be found at     

Antiferromagnetic Exchange Interactions. Part 1. Newly Reported Nickel(II) Complex of the Antiprine Schiff Base of 3-Formylsalicylic Acid

This study reports the magnetic properties of newly reported nickel(II) complex of the antiprine Schiff base of 3-formylsalicylic acid. Using the isotropic magnetic interaction model it is suggested that there is a strong antiferromagnetic interactions between metal centers in dimeric units. It is also suggested that the system become demagnetized below a certain temperature. An erratum to this article can be found at     

UV固化粉末涂料的研究与应用

综述了UV光固化粉末涂料与技术以及主体树脂的研究与发展概况,介绍了UV光固化粉末涂料的特性及应用领域。     

正交法选择COPNA树脂的最佳合成条件

COPNA树脂可作为炭／炭复合材料的基体前驱体。为提高以苯甲醛为交联荆，蔡为单体，浓硫酸为催化剂的缩合多核芳香烃（COPNA）树脂的残炭率，采用正交实验，研究了合成COPNA树脂的交联荆与单体的摩尔比、催化荆的用量、反应温度等因素对树脂的残炭率的影响。结果表明：影响因子强度大小依次为交联剂与单体的摩尔比、催化荆用量、反应温度。通过正交实验得到的最佳反应条件是交联剂与单体的摩尔比为2．5、催化剂的用量为5％、反应温度170℃，此条件下合成的COPNA树脂的残炭率达到76％。     

Microstructure evolution in Si+ ion irradiated and annealed Ti3SiC2 MAX phase

Ti₃SiC₂ samples were irradiated by a 6-MeV Si⁺ ion to a fluence of 2 $\times$ 10¹⁶ Si⁺ ions/cm² at 300°C followed by annealing at 900°C for 5 h. A transmission electron microscope was used to characterize microstructural evolution. The phase of Ti₃SiC₂ transformed from the hexagonal close-packed (HCP) to a face-centered cubic structure after irradiation. Hexagonal screw dislocation networks were identified at the deepest position of the irradiated area, which are the products of dislocations reactions. After annealing, the irradiated region has reverted to the original HCP structure. High-density cavities and stacking faults were formed along the basal planes. In addition, ripplocations have been observed in the irradiated region in the Ti₃SiC₂ sample after annealing. Our insights into the formation processes and corresponding mechanisms of these defect structures might be helpful in the material design of advanced irradiation tolerance materials.     

高能电子束辐射对硼酚醛树脂的影响

对硼酚醛树脂进行了高能电子束辐射,并进行了差热分析、热失重分析、残炭率和炭化后的粉末电阻率测试.结果表明硼酚醛树脂辐射前在100～200 ℃之间有一个明显的吸热反应峰,固化温度范围较大;而经过辐射后,100～300 ℃反应峰较少,硼酚醛树脂的固化温度范围明显减小,且固化温度降低.炭化后粉末电阻率由辐射前的3899.6 μΩ·m显著提高为辐射后的4951.6 μΩ·m;残炭率由60.6%降低为58.1%.     

铜离子-氧化锌/十六烷基铵基吡啶-蒙脱石吸附大肠杆菌的能力

以蒙脱石(montmorillonite,MMT)、铜离子(Cu2 )、氧化锌(ZnO)和十六烷基铵基吡啶(cetylpyridinium,CP)为主要原料,制备了MMT基系列细菌吸附剂Cu2 -ZnO/CP-MMT,Cu2 -ZnO/MMT,ZnO/MMT和MMT,并比较它们吸附大肠杆菌(Escherichia coli,E.coli)的能力.结果表明:上述材料与E.coli作用1.5 h后均可达到吸附平衡,吸附率大小顺序为Cu2 -ZnO/CP-MMT＞Cu2 -ZnO/MMT＞ZnO/MMT＞MMT.介质的pH值、离子强度和吸附温度对MMT基矿物材料吸附E.coli的能力有不同程度的影响.MMT基矿物材料吸附E.coli为吸热过程,在实验温度范围内自发进行.