BY分子筛的合成、表征及其裂化性能考察

采用水热晶化法合成了含杂原子硼的Y型分子筛，利用MAS NMR、XRD、IR等表征方法，证明了硼进入Y型分子筛的骨架中。利用吡啶吸附红外光谱、轻油微反装置分别测定了Y和BY分子筛的表面酸性及其裂化性能。结果表明，硼的引入增加了Y分子筛的B酸中心数目以及裂化和氢转移反应活性，导致裂化汽油中的烯烃明显降低，芳烃随之增加。     

Study on the recovery of hydrogen from refinery (hydrogen + methane) gas mixtures using hydrate technology

A novel technique for separating hydrogen from (H2 CH4) gas mixtures through hydrate formation/dissociation was proposed. In this work, a systematic experimental study was performed on the separation of hydrogen from (H2 CH4) feed mixtures with various hydrogen contents (mole fraction x = 40%-90%). The experimental results showed that the hydrogen content could be enriched to as high as ~94% for various feed mixtures using the proposed hydrate technology under a temperature slightly above 0℃ and a pressure below 5.0 MPa. With the addition of a small amount of suitable additives, the rate of hydrate formation could be increased significantly. Anti-agglomeration was used to disperse hydrate particles into the condensate phase. Instead of preventing hydrate growth (as in the kinetic inhibitor tests), hydrates were allowed to form, but only as small dispersed particles. Anti-agglomeration could keep hydrate particles suspended in a range of condensate types at 1℃ and 5 MPa in the water-in-oil emulsion.     

一类多乘积规划的加速算法

针对一类多乘积规划问题(MP),给出一个加速算法.首先导出一个与(MP)等价的逆凸问题(RCP),然后构造问题(RCP)的线性松弛化问题.算法的主要特点是提出了两个加速技巧,这些技巧可以用于改善算法的收敛速度.数值算例表明算法是可行的.     

聚苯硫醚/聚四氟乙烯复合涂层研究进展

聚苯硫醚、聚四氟乙烯均是耐高温、耐腐蚀的树脂,同时聚四氟乙烯有极低表面能,而聚苯硫醚与金属有良好结合力,结合二者的优点,有望制备出集合耐腐蚀、耐高温、超疏水等优异性能为一体的功能涂层,因此以聚苯硫醚、聚四氟乙烯为主要原料的复合涂料自1992年以来便倍受关注。本文从聚苯硫醚、聚四氟乙烯各自的性能出发,综述了聚苯硫醚/聚四氟乙烯复合涂层三种不同制备工艺:分层涂覆、共混涂覆、梯度涂覆;详细说明了涂层的五大优异性能:耐腐蚀性、超疏水性能、阻垢性能、耐高温性以及耐磨性能,最后本文还描述了聚苯硫醚/聚四氟乙烯复合涂层的广阔应用前景。     

小麦茎秆性状与单穗重的相关分析与通径分析

利用2010-2011连续两年河南科技学院小麦试验田所得的试验资料,对6个不同小麦品种的茎秆性状与单穗重进行相关分析与通径分析.相关分析结果表明,所考查的茎秆性状与单穗重的相关程度依次为:茎重>茎粗>株高>茎长>壁厚;茎重与单穗重(r_(5y)=0.8213~(**))和茎粗与茎重(r_(25)=0.7218~(**))、茎长与株高(r_(13)=0.9582~(**))的相关分别呈极显著,茎粗与单穗重(r_(2y)=0.5990~*)、茎重与株高(r_(13)=0.6550~*)均达显著水平.通径分析结果显示,考查的茎部性状对单穗重的直接效应(绝对值)依次为:茎重>株高>茎长>壁厚>茎粗.茎重的直接正效应(p_(x_5→x_5→y)=1.3986~(**))最大,茎长(p_(x_1→x_1→y)=0.6297~*)次之,壁厚(p_(x_3→x_3→y)=0.2323)居三,株高的直接负效应(p_(x_3→x_3→y)=-1.1617~(**))极显著;5个茎部性状的决策系数依次为:茎重(0.3414)>壁厚(-0.0030)>茎粗(-0.1959)>茎长(一0.2063)>株高(一1.9800).据此明确了茎重、壁厚为提高小麦单穗重的主选因素,株高是主控因素.在注重对基部节间短、粗、茎壁厚性状选择的同时,适当控制株高,是选育高产抗倒小麦品种的有效途径.     

基于实验班管理模式的实验开放教学网络管理系统

针对开放式实验教学中存在的问题,研发了基于实验班管理模式的实验开放教学网络管理系统.本文介绍了该系统的研制背景、基本结构、主要功能及其特点.     

Role of surface roughness in the magnesite flotation and its mechanism

Surface roughness has a significant influence on mineral flotation. The assisting effect of surface roughness on minerals flotation is extensively investigated from its physical properties (e.g., the existing form of asperity and its size), however, the associated effect on mineral flotation based on the differences in surface chemical property caused by surface roughness has been rarely touched. With such a question in mind, in this study, we investigated the flotation recoveries of two batches of magnesite particles with varying degree of surface roughness produced by two different mills, and associated the flotation performances to their surface chemical properties (amount of adsorption sites for the collector) via a series of detections, including Scanning Electron Microscope-Energy Dispersive Spectrometry (SEM-EDS) observations, X-ray photoelectron spectroscopy (XPS) analysis, adsorption capacity tests, and contact angle measurements. Finally, we concluded that rougher magnesite particles could provide more active sites (Mg²⁺) for a larger capacity of sodium oleate (NaOL), thereby improving the hydrophobicity and floatability.     

多硫化钴CoSx结构与稳定性的密度泛函研究

采用量子化学密度泛函方法计算得到CoSx(x=1~6)6组化合物的同分异构体及CoS2的晶体结构.对其分子结构与稳定性、光谱性质及其晶体结构性质进行了分析讨论.发现CoSx和晶体结构中Co原子均带部分正电荷,S原子均带部分负电荷;Co可与不同比例的S原子形成配位键,并有很强的结合能.随着S原子比例的增加配位键伸长,结合能增大.计算的晶体结构数据很好地与实验测定结构吻合.计算结果可为锂插层研究提供有用的信息.     

Physical analysis of normally-off ALD Al2O3/GaN MOSFET with different substrates using self-terminating thermal oxidation-assisted wet etching technique

Based on the self-terminating thermal oxidation-assisted wet etching technique, two kinds of enhancement mode Al$_{2}$O$_{3}$/GaN MOSFETs (metal-oxide-semiconductor field-effect transistors) separately with sapphire substrate and Si substrate are prepared. It is found that the performance of sapphire substrate device is better than that of silicon substrate. Comparing these two devices, the maximum drain current of sapphire substrate device (401 mA/mm) is 1.76 times that of silicon substrate device (228 mA/mm), and the field-effect mobility ($\mu_{\rm FEmax}$) of sapphire substrate device (176 cm$^{2}$/V$\cdot$s) is 1.83 times that of silicon substrate device (96 cm$^{2}$/V$\cdot$s). The conductive resistance of silicon substrate device is 21.2 $\Omega {\cdot }$mm, while that of sapphire substrate device is only 15.2 $\Omega {\cdot }$mm, which is 61% that of silicon substrate device. The significant difference in performance between sapphire substrate and Si substrate is related to the differences in interface and border trap near Al$_{2}$O$_{3}$/GaN interface. Experimental studies show that (i) interface/border trap density in the sapphire substrate device is one order of magnitude lower than in the Si substrate device, (ii) Both the border traps in Al$_{2}$O$_{3}$ dielectric near Al$_{2}$O$_{3}$/GaN and the interface traps in Al$_{2}$O$_{3}$/GaN interface have a significantly effect on device channel mobility, and (iii) the properties of gallium nitride materials on different substrates are different due to wet etching. The research results in this work provide a reference for further optimizing the performances of silicon substrate devices.