预测水平管气-液环状流周向液膜厚度分布的理论模型

针对水平环状流液膜厚度沿周向分布的不对称性 ,用 5组双平行电导探针测量了水平管内气液环状流沿周向的瞬态液膜厚度 ,得到了平均液膜厚度沿周向的分布规律 .分析了液膜向上输送的机理 .为更为准确地预测液膜厚度 ,综合考虑了扰动波抽吸作用机理、气体二次流机理及液滴沉降和携带机理 ;通过量级比较和应力平衡的方法 ,提出了一个预测液膜厚度沿周向分布的理论模型 .数值模拟结果表明预测值与实验测量结果符合较好     

A facile one-step hydrothermal method to produce graphene–MoO3 nanorod bundle composites

We describe a facile in situ hydrothermal fabrication of graphene–MoO₃ nanorod bundle composites utilizing sodium salicylate. The structure, morphology and composition of graphen–MoO₃ composites were investigated by means of field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy and thermogravimetric-differential scanning calorimetry (TG-DSC). FESEM and TEM studies show that the presence of ordered MoO₃ nanorod bundles in composites, the characterization results of XRD, Raman spectra and TG-DSC analysis confirm the reduction of graphite oxide (GO) to graphene accompanying by the formation of MoO₃ nanorod bundles in the hydrothermal process. Due to characteristics of MoO₃ and graphene–MoO₃ composites, our findings may have implications in the synthesis and fabrication of well-defined functional graphene–MoO₃ hybrid materials. It may also provide a general approach for the preparation of graphene–metal oxide hybrid materials.     

中西医结合保留灌肠治疗放射性直肠炎临床观察(附病例36例)

放射性直肠炎是盆腔、腹腔、腹膜后恶性肿瘤经放射治疗后引起的常见并发症。我科近2年来采用中西医结合保留灌肠治疗取得显著疗效。     

利用拨号网络实现自动气象站观测资料的自动传输

通过建立拨号网络连接并在自动气象站监控软件(SAWSS)中正确设置自动站组网的方法,在宽带网络出现故障时,利用备份拨号网络实现自动气象站观测资料的即传即拨、传完即断,达到既可以保障观测资料传输的时效性,又可以减轻观测人员工作强度,节约办公经费的目的,可在各观测台站推广使用。     

基于神经网络的卷烟共线分拣系统自适应控制

针对目前方法自适应控制卷烟共线系统时,由于未能依据Lyapunov函数确定系统的控制规律,导致在实施系统自适应控制时,存在控制效果差、控制误差高和控制性能低的问题,提出基于神经网络的卷烟共线分拣系统自适应控制方法。首先依据Lyapunov函数确定系统的控制规律,建立对象控制模型并使用前馈神经网络训练模型,优化控制器参数,完成控制器的设计;再利用控制器的参数建立线性和非线性2种自适应控制方法;最后通过制定的切换规则,完成自适应算法的平滑转换,实现系统的自适应控制。实验结果表明,运用该方法控制系统时,控制效果好、控制误差低以及控制性能高。     

Solid biopolymer electrolytes based on all-cellulose composites prepared by partially dissolving cellulosic fibers in the ionic liquid 1-butyl-3-methylimidazolium chloride

This study investigated the effects of an ionic liquid, 1-butyl-3-methylimidazolium chloride ([Bmim]Cl), as a doping salt, on the properties of resulting solid biopolymer electrolytes (SPEs) based on all-cellulose composites. The conductivity of the resulting SPEs increased with the [Bmim]Cl loading. Both incubation time and chemical loading affected the tensile properties of the SPEs. The SPEs prepared under the optimum processing conditions exhibited a tensile strength and conductivity of 18.2 MPa and 1.28 × 10⁻³ S cm⁻¹, respectively, when tested at room temperature. FTIR and XPS spectra showed that the concentration of [Bmim]Cl in the SPEs was greater at the surface than at the interior. Treatment with [Bmim]Cl resulted in a decrease in the crystallinity and thermal stability of the SPEs as evidenced by XRD and TGA analyses. This study demonstrates that treatment of cellulosic materials with the ionic liquid [Bmim]Cl can create biomass-based SPEs with high conductivity, improved mechanical properties, good thermal stability and easy processability.     

Experimental Study on the Characteristics of Liquid Layer and Disturbance Waves in Horizontal Annular Flow

INTRODUCTIONGas-liquid two-phase annular flow is encountered ina wide range of industrial applications, including nuclear reactors, evaporators and condensers. The studyof annular flow not only because of the need to understand the heat transfer characteristics of such aflow, but also because annular flow may be precursory to liquid dryout in the challnel, which is significant in nuclear reactor safety and in corrosion pre-vention. An important feature of horizontal annularflow is the effe…     

谈建设项目管理与施工项目管理的区别

在实际工作中 ,建设项目管理与施工项目管理的概念经常混淆 ,本文从管理主体、管理范围、管理内容和管理目标等几个方面论述了二着的区别与联系 ,以避免在工程项目管理工作中因概念不清而产生混乱和失误     

Thermal,crystallization, and dynamic rheological behavior of wood particle/HDPE composites: Effect of removal of wood cell wall composition

This study investigated the effect of removal of wood cell wall composition on thermal, crystallization, and dynamic rheological behavior of the resulting high density polyethylene (HDPE) composites. Four types of wood particle (WP) with different compositions: native wood flour (WF), hemicellulose‐removed wood particle (HR), lignin‐removed wood particle (holocellulose, HC), and both hemicellulose and lignin removed particle (α‐cellulose, αC) were prepared and compounded with HDPE using extruder, both with and without maleated polyethylene (MAPE). Results show that removal of the hemicellulose improved the thermal stability of composites, while removal of the lignin facilitated thermal decomposition. WPs acted as nucleating agents and facilitated the process of crystallization, thereby increasing the crystallization temperature and degree of crystallinity. The crystallization nucleation and growth rate of αC and HR based composites without MAPE decreased, as compared with WF based one. Composite melts with and without MAPE exhibited a decreasing order of storage modulus, loss modulus, and complex viscosity as αC > WF > HR > HC and αC > HR > WF > HC, respectively. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40331.     

碳热还原-化合反应制备超细TiCN粉末工艺与特性表征研究

以TiO2和制粒碳为原料,采用搅拌球磨-碳氮化工艺,在N2气氛中,通过碳热原位还原-化合反应,制备Ti(C1-x,Nx)粉末。研究了3种反应温度(1 600、1 700℃和1 800℃)和4组原料粉末摩尔比(n(C)/n(Ti)=2.3、2.4、2.5和2.6)对Ti(C1-x,Nx)粉末的物相、化学成分和粒度的影响。结果表明,在实验条件下制备的粉末均为单一物相成分;随反应温度升高和n(C)/n(Ti)增大,Ti(C1-x,Nx)粉末的x值随之降低;1 600℃条件下,当n(C)/n(Ti)为2.4时,合成的Ti(C1-x,Nx)粉末近似化学式为Ti(C0.41,N0.59),O和Cf含量均为0.25%,平均粒径约为0.7μm;1 700℃条件下,当n(C)/n(Ti)为2.6时,合成的Ti(C1-x,Nx)粉末近似化学式分别为Ti(C0.59,N0.41),O和Cf含量分别为0.13%和0.31%,平均粒径约为0.8μm。在此工艺条件下,制备的粉末各项综合性能指标相对较好。