A facile co-solvent strategy for preparation of graphene nanoplatelet powder: An industrially viable innovative approach

We report an industrially viable promising approach to produce micrometer-sized multilayer graphene nanoplatelet powder (MGNP) in a scalable quantity via microwave-assisted exfoliation of graphite (MEG) and fragmented into MGNP through liquid-phase exfoliation in the co-solvent mixture by kitchen mixer (KM). KM allows rapid delaminating MEG into MGNP by shear force dominated exfoliation. Majority of MGNPs are with a diameter of few micrometers and thickness is in nanometers. MGNP are crystalline with very limited defects was confirmed by Raman measurements and transmission electron microscopy. This process transforms, more than 86% of graphite flakes into MGNP. This advanced approach opens a new pathway to produce MGNP in bulk quantity as it is feasible, rapid, and cost-effective.     

From Long Infrared to Very Long Infrared Wavelength Focal Plane Arrays Made with HgCdTe n + n ?/ p Ion Implantation Technology

This paper aims at studying the feasibility of very long infrared wavelength (VLWIR) (12–18 μm) focal plane arrays using n-on-p planar ion-implanted technology. To explore and analyze the feasibility of such VLWIR detectors, a set of four Cd _x Hg_1−x Te LPE layers with an 18 μ cutoff at 50 K has been processed at Defir (LETI/LIR–Sofradir joint laboratory), using both our “standard” n-on-p process and our improved low dark current process. Several 320 × 256 arrays, 30-μm pitch, have been hybridized on standard Sofradir readout circuits and tested. Small dimension test arrays characterization is also presented. Measured photonic currents with a 20°C black body suggest an internal quantum efficiency above 50%. Typical I(V) curves and thermal evolution of the saturation current are discussed, showing that standard photodiodes remain diffusion limited at low biases for temperatures down to 30 K. Moreover, the dark current gain brought by the improved process is clearly visible for temperatures higher than 40 K. Noise measurements are also discussed showing that a very large majority of detectors appeared background limited under usual illumination and biases. In our opinion, such results demonstrate the feasibility of high-performance complex focal plane arrays in the VLWIR range at medium term.     

二维无机功能材料

简要介绍了一种通过层状结构材料剥离成单分子层的无机二维功能材料。     

Effect of Particle Size on Monometallic and Bimetallic (Au,Pd)/C on the Liquid Phase Oxidation of Glycerol

The influence of metal particle size of monometallic and bimetallic supported catalysts (Au, Pd, Au–Pd)/C was studied using as a model reaction the liquid phase oxidation of glycerol. By tuning the metal particle size from 2 to 16 nm a progressive decrease of activity and simultaneously an increase in the selectivity to sodium glycerate was observed. Moreover, the influence of the temperature was studied and it was found that by increasing the temperature, only with a large particle size the formed glycerate was retained and not over-oxidized to tartronate.     

La-OMS-2催化剂催化甲苯氧化制苯甲醛

合成了氧化锰八面体(OMS-2)分子筛,采用离子交换法和浸渍法制备了稀土金属La改性的OMS-2分子筛(La-OMS-2)催化剂,并用于甲苯液相选择性氧化制苯甲醛,考察了催化剂用量、反应温度、反应时间、氧气流量及溶剂种类对甲苯转化率和苯甲醛选择性的影响,对La-OMS-2催化剂进行了X射线衍射表征和BET比表面积测定。实验结果表明,离子交换法制备的La-OMS-2-A催化剂的活性高于浸渍法制备的La-OMS-2-B催化剂,在甲苯0.1mol、溶剂冰乙酸10mL、氧气流量60mL/min、La-OMS-2-A催化剂用量0.10g、反应温度353K、反应时间1.0h的条件下,甲苯转化率达61%,苯甲醛收率为56%。加入La对OMS-2分子筛中的MnO晶格结构产生了影响,提高了苯甲醛的收率。     

铝-锂合金腐蚀性能研究综述

综述了铝-锂合金孔蚀、晶间腐蚀、应力腐蚀断裂(SCC)及剥蚀的研究现状。阐述了加工状态、热处理、显徽组织及腐蚀介质对一些铝-锂合金孔蚀及晶间腐蚀行为与SCC敏感性的影响及其影响机制．同时报道了一些研究铝-锂合金剥蚀的新方法，并提出了进一步研究的方向．     

铝合金剥蚀过程的电化学阻抗谱分析

研究了轧制态及峰时效8090铝—锂合金、拉应力作用下及无应力作用时双级过时效7075铝合金的剥蚀发展过程，测量并拟合了合金发生剥蚀后的电化学阻抗谱。结果表明：发生剥蚀后，合金电化学阻抗谱由高—中频和中—低频容抗弧组成；可从电化学阻抗谱的拟合参数(变化趋势)得到剥蚀的相关信息。如剥蚀发展速度、剥蚀形貌、剥蚀表层是否脱落等．     

对甲基苯甲酸液相催化氧化动力学

研究了以醋酸钴和醋酸锰为催化剂、氢溴酸为促进剂,在169～192 ℃下对甲基苯甲酸(p-TA)的液相氧化反应动力学.采用幂函数动力学模型对实验数据进行了拟合.结果表明,对甲基苯甲酸液相氧化反应是串联反应,甲基苯甲酸和中间产物对羧基苯甲醛的反应级数均为1.拟合得到的活化能数据表明对甲基苯甲酸氧化为整个反应的控制步骤.利用该动力学模型能够成功预测186 ℃下液相组分随时间的变化趋势.实验表明,当金属离子的配比满足[Co2 ]/[Mn2 ]为3∶1时,催化剂具有最高的活性.     

液相催化调聚合成卤代烃的催化剂研究进展

综述了卤代烷与烯烃调聚合成卤代烃的催化剂体系，包括铜催化剂、铁催化剂、镍催化剂和复合金属催化剂等无载体型催化剂和负载型催化剂。     

液相沉淀法制备纳米TiO2及其光催化性能的研究

提出了一种以TiSO₄为前驱体的制备锐钛矿型纳米TiO₂的液相沉淀法。通过控制适宜的制备条件，可将Ti^4+的初始浓度提高到15 mol·L^-1。以丙烯酰胺的光催化降解为模型反应，考察了所制备TiO₂的光催化活性。与萃取沉淀法制备的TiO₂和工业催化剂相比，该法制备的TiO₂不仅产率高，而且催化活性较好。