Reaction condition optimization and kinetic investigation of roasting zinc oxide ore using (NH<Subscript>4</Subscript>)<Subscript>2</Subscript>SO<Subscript>4</Subscript>

An orthogonal test was used to optimize the reaction conditions of roasting zinc oxide ore using (NH₄)₂SO₄. The optimized reaction conditions are defined as an (NH₄)₂SO₄/zinc molar ratio of 1.4:1, a roasting temperature of 440°C, and a thermostatic time of 60 min. The molar ratio of (NH₄)₂SO₄/zinc is the most predominant factor and the roasting temperature is the second significant factor that governs the zinc extraction. Thermogravimetric–differential thermal analysis was used for (NH₄)₂SO₄ and zinc mixed in a molar ratio of 1.4:1 at the heating rates of 5, 10, 15, and 20 K·min-1. Two strong endothermic peaks indicate that the complex chemical reactions occur at approximately 290°C and 400°C. XRD analysis was employed to examine the transformations of mineral phases during roasting process. Kinetic parameters, including reaction apparent activation energy, reaction order, and frequency factor, were calculated by the Doyle–Ozawa and Kissinger methods. Corresponding to the two endothermic peaks, the kinetic equations were obtained.     

基于Matlab的小世界网络仿真

本文基于Matlab软件实现小世界网络模型算法,并利用Pajek软件做出小世界网络的图像,为培养学生的数学建模能力提供了一个较好的案例。     

葫芦科作物离体雌核发育的研究进展

对葫芦科作物离体雌核发育的研究进行了综述,包括离体雌核发育的研究现状、以及基因型、胚囊发育时期、培养基、预处理、培养方式等因素对离体雌核发育的影响,并对离体雌核研究的发育趋势进行了预测.     

基于年度变更平衡表的土地利用结构演变预测——以苏州市为例

目前,基于年度变更平衡表对土地利用演变进行预测的研究较少.本文利用苏州市1998~2008年土地利用变更平衡表,运用Markov预测模型对全市土地利用结构变化进行模拟、检验和预测,并对苏州市土地利用结构何时达到稳定状态进行了探究.结果表明:基于变更平衡表,运用马尔科夫模型预测土地利用结构的方法是切实可行的;至2020年,苏州市农用地、农村居民点用地、未利用地面积逐年减少,且耕地面积减少最明显;城镇建设用地、独立工矿用地、交通运输用地面积逐年增加;到2042年,苏州市的土地利用结构将逐步趋于稳定.本文的研究对于土地利用年度变更平衡表的深入应用有一定的借鉴意义.     

Numerical analysis of the two-phase pressure drop and liquid distribution in single-screw expander prototype

In this paper, the numerical simulations have been carried out to evaluate the two-phase pressure drop and liquid distribution in screw channel. The numerical models are validated against the present experimental data with statistical accuracy. The effects of pitch circle diameter （PCD）, inlet velocity and inlet sectional liquid holdup on the pressure drop and liquid distribution characteristics in the screw channel are illustrated. It is found that decreasing the PCD and increasing the inlet sectional liquid holdup can increase the liquid holdup on the outer side in screw channel. The PCD and the inlet sectional liquid holdup need to be considered in evaluating the two-phase frictional pressure drop per unit length in the screw channel. The PCD has an effect on the development of the average pressure in the various cross sections, and the inlet sectional liquid holdup has no visible impact on the changing process of the pressure drop in the screw channel. The correlation developed predicts the two-phase frictional pressure drop in the screw channel with great statistical accuracy.     

Dynamics of a qubit—TLS system under resonant microwave driving

We demonstrate the effect of different coupling strengths between a microscopic two-level system(TLS)and a microwave field on the dynamics of a qubit—TLS system when the bipartite system is subject to resonant microwave driving.Rabi beating with a different TLSmicrowave coupling strength is demonstrated in simulations.Entanglement,quantified by the concurrence between the qubit and TLS,both for pure states and mixed states,is simulated.When decoherence is considered,entanglement of the bipartite system oscillates with damping and exhibits entanglement sudden death and/or entanglement sudden death and revival.     

Research progress of trust evaluation model

Software systems in distributed environment are changing from a close and relatively static form, whose users are familiar with each other, to an open and highly dynamic mode, which can be visited by public. In such circumstance, trust evaluation model becomes focus of intense research at current time. Trust evaluation model establishes a management framework of trust relationship between entities, involving expression and measurement of trust, comprehensive calculation of direct trust value and recommended trust value, and recognition of malicious entities and recommendations. Based on the analysis of several typical trust evaluation models, the classification of trust evaluation ideas and modes is discussed, the questions existing in current research and the directions of future research are pointed out.     

摩梭建筑艺术中的宗教禁忌与文化内涵

宗教禁忌的基本功能是确定人们在认识上和社会生活与交往中一些不可逾越的界限,将人类文化与生活纳入有序的制度化模式之中.这种功能影响到了摩梭人的生活方式与造物理念,同时也清晰的反映在他们房屋构建的时间与空间的划分上.这种划分并不是一种纯粹物理性质的划分,而是有着明显的文化内涵.摩梭人不仅为了栖身而分割空间,更要赋予房屋建筑以意义.     

Research on characters of surrounding rock in complex geology conditions and supporting time

The methods combined by test, field monitoring and theoretical analysis were adopted to do the systemic research on the rock mass from micro-structure to macro-deformation, and rheological model of Jinchuan rock mass was established to discuss the reasonable supporting time. Resuhs show that supporting after suitable stress and displacement release can benefit for the long-term stability of surrounding rock.     

基于硝酸盐为前驱体的溶胶凝胶法制备CuInSe2薄膜

采用低成本的无机盐为前驱体,通过溶胶凝胶法制备了高质量的黄铜矿结构CulnSe2太阳能电池光吸收层薄膜.先将制备得到的溶胶通过旋涂甩胶的方法成膜,再先后置于氢气中还原和在硒蒸气中进行硒化处理,即可得到所需薄膜.通过XRD,XRF,SEM和Raman散射等对材料的结构和形貌进行表征.结果表明:采用这种简单的方法所制备的薄膜除了具备平整度好、结晶度高和致密性好等优点外,Raman散射还表明薄膜表面不存在Cu2-xSe等杂相,上述优点非常有利于后续高质量的薄膜太阳能电池的制作.最后,讨论了CuInSe2薄膜中分层现象的产生以及形成机理.