二氧化钛在催化领域的研究进展

TiO2材料以其独特的性质成为催化领域的研究热点.综述了近年来TiO2在催化氧化、光催化剂、固体酸、烟气脱硝、催化加氢等领域的研究进展,并对TiO2在催化领域尚待深入研究的问题进行了探讨     

Synthesis and characterization of alkali‐soluble photosensitive polysiloxane urethane acrylate

A new negative temperature coefficient of resistor (NTCR) thermistors based on nitrile butadiene rubber/magnetite (NBR/Fe₃O₄) nanocomposites were successfully fabricated by conventional roll milling technique. X‐ray diffraction and transmission (TEM) analysis showed that the product is mainly magnetite nanoparticles with diameter of 10‐13 nm. The microstructure of (NBR/Fe₃O₄) nanocomposites were examined by scanning electron microscopy (SEM) and FTIR spectroscopy. The dispersion of magnetite nanoparticles in the NBR rubber matrix and interfacial bonding between them were rather good. The thermal stability of nanocomposites was also obviously improved with the inclusion of the magnetite nanoparticles. The thermal conductivity, thermal diffusivity and specific heat of nanocomposites were investigated. The electrical conductivity of the NBR/Fe₃O₄ increases with the rise in temperature exhibiting a typical negative temperature coefficient of resistance (NTCR) behavior like a semiconductor. The nature of the temperature variation of electrical conductivity and values of activation and hopping energy, suggest that the transport conduction process is controlled by hopping mechanism. Values of characteristics parameters of the thermistors like thermistor constant, thermistor sensitivity and thermistor stability is quite good for practical application as NTCR devices at high temperature. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

电火一体抗击无人机的拦截打击排序模型研究

在信息技术革命的推动下,空袭和反空袭作战模式以及相应的战争形态发生了巨大变化.一方面随着无人机武器的高速发展,无人机将可能成为未来空天战场的主力力量;另一方面,随着我军现代化程度的提升,火力装备水平和信息化电子对抗手段都有了质的飞跃,具备了"电火一体"抗击无人机的作战能力.同时由于信息技术的发展,使得战场态势复杂且瞬息...     

PLD preparation of GeS6 amorphous film and investigation on its photo-induced darkening phenomenon

GeS6 chalcogenide amorphous fi lm was deposited on glass substrate via PLD（pulsed laser deposition） technique. The performance and structure of the fi lm was characterized by XRD（X-ray diffraction）, SEM（Scanning Electron Microscopy）, EDS（Energy Dispersive Spectroscopy）, optical transmission spectra, and Raman spectra, etc. The GeS6 amorphous fi lm was irradiated by 532 nm linearly polarized light, and its photoinduced darkening was investigated. The results showed that the GeS6 chalcogenide amorphous fi lm was smooth and compact with uniform thickness and combined with the substrate fi rmly, and its chemical composition was in consistency with the bulky target. When laser energy was fi xed, the transparence of the fi lm declined with the increase of the laser irradiation time. Obvious photo-induced darkening and relaxation phenomenon of the fi lm after laser irradiation were observed in this investigation.     

不同碱源对Sm（OH）3纳米晶的结构和光催化性能的影响

以Sm(NO3)3·6H2O、氨水、NaOH、乙二胺和二乙烯三胺为主要原料,蒸馏水为溶剂,在水浴条件下分别制得了颗粒状和棒状结构的Sm(OH)3纳米晶.采用X-射线衍射仪(XRD)、扫描电子显微镜(SEM)和Lambda 950分光光度计分别对产物的物相、形貌和光学性能进行表征,研究了不同碱源对Sm(OH)3纳米晶的结构和光催化性能的影响.结果表明:水浴条件下,弱碱氨水不利于Sm(OH)3纳米晶的结晶生长过程的进行,所得产物呈现非晶颗粒的团聚体;在强碱乙二胺和二乙烯三胺作用下得到了结晶性良好的棒状结构的产物,且棒的长径比的增大有益于产物光催化性能的提高.     

化学镀在换热表面强化滴状凝结、阻垢、耐蚀研究进展

从换热器实际问题出发,分别回顾了化学镀层强化凝结换热、阻垢、耐蚀3个方面的研究进展。在强化凝结换热方面,阐述了以Ni-P化学镀为基础的界面表面能、镀层非晶含量、温度、压力以及添加PTFE等物质对在换热界面形成滴状凝结的影响。在化学镀阻垢方面,介绍了污垢的生长过程,讨论了镀层非晶含量、实验条件、梯度镀层以及添加W、BN、Sn、Cu等元素对镀层阻垢性能的影响。在化学镀耐腐蚀研究方面,阐述了镀层磷含量、梯度镀层、表面活性剂、镀液pH值、温度以及添加Cu、PTFE等元素对镀层抗腐蚀性能的影响。并根据实际生产情况,提出对镀层强化凝结换热、阻垢和耐腐蚀3个方面特性相互间的影响关系进行研究。同时提出,为了推进镀层技术工业化发展,还应解决镀层长效性的问题。     

Removal of Hg0 from flue gas using two homogeneous photo‐fenton‐like reactions

Removal of Hg⁰ using two homogeneous Photo‐Fenton‐Like reactions was first investigated in a photochemical reactor. Effects of process parameters on Hg⁰ removal were studied. Free radical and reaction products were analyzed. Removal pathways of Hg⁰ were discussed. Simultaneous removal of Hg⁰, NO, and SO₂ is also studied briefly. The results show that UV power, wavelength, H₂O₂ concentration, and solution pH have great effects on Hg⁰ removal. Hg⁰, and SO₂ concentrations, solution temperature, Fe³⁺, Cu²⁺, , and concentrations also have significant effects on Hg⁰ removal. However, concentrations of CO₂, NO, O₂, Cl^?, , , SiO₂, Al₂O₃, and Fe₂O₃ only have slight effects on Hg⁰ removal. Hg⁰/NO/SO₂ can be simultaneously removed by Photo‐Fenton‐Like reactions. ·OH was captured, and / /Hg²⁺ were also detected. Removals of Hg⁰ by photochemical oxidation and ·OH oxidation play a major role, and removal of Hg⁰ by H₂O₂ oxidation only plays a secondary role in removal of Hg⁰. © 2015 American Institute of Chemical Engineers AIChE J, 61: 1322–1333, 2015