辐照损伤对锆合金电化学性能的影响

综述了堆内辐照对锆合金电化学性能影响的概况，浅析了堆内辐照损伤的机理，并重点探讨了主要的堆内辐照源——中子辐照对锆合金微观结构与氧化性能的影响。进一步阐述了堆外离子轰击模拟堆内中子辐照研究方法的进展概况，并就离子轰击实验参量的选择进行了较为深入的分析。     

Synthesis and electrochemical properties of Th-doped LiMn2O4 powders for lithium-ion batteries

To improve the cycle performance of eco-friendly and cost-effective spinel LiMN2O4 as the Li secondary batteries, the Th-doped LiThxMn1-xO4 spinel powers were synthesized by solid-state method. The starting materials, Li2CO3,MnO2 and Th(NO3)4·4H2O, were mixed uniformly using a traditional ball milling, which resulted in a uniform particle size distribution in the mixed powers. Tests of X-ray diffraction, SEM, impedance spectra and charge-discharge were carried out for LiThxMn1-xO4 cathode materials. Results show that the synthesized LiTh0.01Mn1.99O4 material exhibits standard spinel structure, regular particle morphology and excellent property of charge-discharge for big current. The capacity retention of the material modified by doping Th is more than 85.1% of the first discharge specific capacity of 111.5 mAh·g -1 after 20 cycles at the current rate 1C, while the pristine LiMN2O4 is only 57% of the first discharge specific capacity of 110.2 mAh·g-1 after the same cycles at the same current rate.     

40CrNiMo钢形变离子注入复合强化机理研究

对40CrNiMo钢施行形变离子注入复合强化处理工艺,通过对未处理件、形变强化处理件、离子注入件及形变与离子注入复合强化处理件的表面显微硬度、残余应力、摩擦磨损等性能的分析和比较,探讨形变离子注入的强化机理及最佳工艺参数。结果表明,经上述各种处理后,显微硬度和耐磨性均有所提高,其中形变与离子注入复合处理后的效果更为明显。分析表明,表层硬相化合物的形成及晶粒细化是材料表面耐磨性提高的主要原因,残余应力的增加提高了抗疲劳性。     

The effect of niobium ion implantation on the oxidation behavior of aγ-TiAl-based intermetallic

The effect of niobium implantation (2×10¹⁶ and 10¹⁷ ions/cm²) on the oxidation behavior of a -TiAl-based intermetallic alloy Ti–48Al–2Cr in air at 800°C has been examined. Isothermal studies with exposure times up to 200 hr and cyclic-oxidation tests up to 800 hr revealed a negligible effect for the low implantation dose. However, a remarkable decrease in oxidation rates was observed for the material implanted with 10¹⁷ Nb ions/cm². The improvement in the oxidation resistance appeared to be similar to that obtained by alloying of the intermetallic with a few atomic percent niobium. Possible mechanisms for the effect of niobium on the oxidation resistance of TiAl-base intermetallics are discussed in view of the results obtained for the implanted material.     

离子交换树脂非均相催化乙酰化合成乙酰甲胺磷

研究了在间易搅拌釜中以阳离子交换树脂为催化剂，由甲胺磷催化乙酰化合成乙酰甲胺磷。分别考察了不同类型离子交换树脂的催化乙酰化作用。并且研究了搅拌速度，催化剂用量以及反应温度对乙酰化反应的影响。研究结果表明，以NKC9型离子交换树脂在333.15K温度下具有最好的催化乙酰化作用。     

Magneto-sensitive nickel nanowires fabricated by electrodeposition into multi- and single-ion track templates

Polycarbonate templates of (30±1) μm thickness containing cylindrical etched-track nanochannels of (500±50) nm diameter were used for electrodeposition of Ni nanowires. Using 10⁴ channels per cm², the most favourable deposition potential of  − 1.0 V was determined in a potentiostatic mode by varying the deposition potential with respect to an Ag/AgCl reference electrode over a range between  − 0.1 V and  − 1.5 V. The deposition efficiency at  − 1.0 V was estimated around 10%. The resulting single wires had a resistance around 200 Ω and showed an anisotropic magnetoresistance (AMR) effect of 1%, applicable to directionally sensitive magnetic field sensors.     

废旧电池中有价金属回收利用探讨

随着中国经济的稳步发展和投资环境的不断优化,中国已成为电池的制造和消费大国,每年产生数亿只废旧电池。对废旧电池的回收利用已成为全社会关注的问题。介绍了废旧电池中有价金属的回收利用方法,着重介绍了锂离子二次电池正极材料有价金属的回收利用方法。指出,中国商品化的正极材料只有钴酸锂（LiCoO2）,这种正极材料钴含量高,且钴价值高,并且回收工艺可行,因此,从钴酸锂正极材料中回收钴等有价金属,对发展中国的循环经济具有重要意义。同时介绍了锂离子二次电池正极材料的研究现状。     

Cooperative effect of crystallization temperature and NaF addition in the formation process and hydrothermal stability of MCM-48 mesoporous molecular sieve

The hydrothermal stability of MCM-48 was conveniently and effectively improved by increasing the crystallization temperature and directly adding NaF to the synthesis gel. The crystallization temperature varied from 373 K to 403 K. The influences of NaF addition, crystallization temperature and crystallization time on the formation process and hydrothermal stability of MCM-48 were systematically studied here to solve the problem of poor reproducibility. Results from XRD patterns indicated that the crystallization temperature and crystallization time were very critical factors for the improvement of the hydrothermal stability besides NaF addition. The formation process of MCM-48 was significantly accelerated and the pore structure ordering was also greatly improved by increasing the crystallization temperature and F⁻/Si ratio. A high hydrothermally stable MCM-48 mesoporous molecular sieve was obtained after being crystallized at 393 K for 36 h in the presence of NaF, which endured the hydrothermal treatment in boiling water at least for 4 days. However, only an amorphous product was obtained when the crystallization temperature was further increased to 403 K. Results from Si MAS NMR, N₂ adsorption isotherms, TEM, Raman spectra and XRD patterns manifested that the improved stability of MCM-48 was attributed to the high silicates condensation degree and the excellent pore structure ordering. The possible reason for the successful formation of hydrothermally stable MCM-48 sample by controlling the crystallization temperature, time and F⁻/Si ratio was explained here.     

Investigation of transport phenomena in a hybrid ion exchange-electrodialysis system for the removal of copper ions

Hybrid ion exchange electrodialysis processes allow the removal of metal ions from dilute waste liquids and the recovery of more concentrated solutions. The work reported here was aimed at investigating the two steps in the treatment process, namely, adsorption of metal ions onto the packed bed of resin and electromigration (i.e., the transport of these ions in the complex system under the applied electrical field). The case of copper sulfate was investigated. Dowex resins with a cross-linking degree of 2 and 8% were used. The flux of copper through the resin bed and the current efficiency for ion transfer to the cathode compartment were determined as a function of potential gradient and copper ionic fraction in the bed. Apparent diffusion coefficients of Cu²⁺ in the overall system were deduced from the experimental data.     

Improvement of structural stability and electrochemical activity of a cathode material LiNi0.7Co0.3O2 by chlorine doping

In the process of Li⁺ intercalation-deintercalation, electron removal is accompanied simultaneously. Oxygen was found to compensate electron removal both in theoretical calculations and practical experiments. Chlorine addition to LiNi_0.7Co_0.3O₂ was expected to exchange electrons in that Cl⁻ was easier to lose electrons than O²⁻. LiNi_0.7Co_0.3O_2−xCl_x was identified as a pure hexagonal lattice of α-NaFeO₂ type by X-ray diffraction. X-ray photoelectron spectroscopy was used to analyze the influence of chlorine substitution on the oxidation state of transition-metal ions. Charge-discharge experiments and cyclic voltammetry confirmed that chlorine addition was an effective way to improve reversible capacity and structural stability in cycles.