低品位白钨矿选矿技术的研究发展

系统地介绍我国低品位白钨矿选矿技术现状及发展。详细阐述了浮选、非浮选选矿工艺以及选矿联合工艺在低品位白钨矿的选矿中的作用及其进展。重点指出对于品位低、组分复杂、细粒嵌布的白钨矿,单一选矿工艺已经很难解决问题,加大力度研究重、磁、浮、化等选矿工艺之间联系,组成联合工艺,实现各个工艺之间的优劣势互相补充,协同效应最大化,是未来大力度开发利用低品位白钨矿,保持我国钨业持续发展的发展方向。     

采空区群失稳模型构建及隔离矿柱安全厚度研究

许多金属矿山存在采空区群安全隐患。基于CMS对某矿山的采空区群开展定期探测,形成动态监测机制,精确获取采空区群三维边界;研究构建空区群连锁式失稳模型：基于突变理论分析方法,构建了采空区顶板-隔离矿柱力学模型,提出隔离矿柱失稳的判据,计算合理的隔离矿柱安全厚度,阻断空区群连锁失稳过程。运用数值模拟验证了计算结果的合理性。研究表明通过精确控制隔离矿柱的安全厚度,可有效阻断空区群连锁失稳导致的工程灾害;计算结果为下一步资源回采方案提供了设计参考。     

金属矿山全尾砂胶结充填对地下水中重金属含量的影响试验

为了探讨金属矿山尾砂胶结充填是否会对地下水造成污染,本试验分别采用1:4和1:6两种不同的灰砂比(水泥/尾砂)制成胶结充填体试块在不同来源地下水水样中浸泡。浸泡后水样中的重金属含量与《地下水质量标准》(GB/T 14848-93)Ⅲ类标准规定的含量限值进行对照分析。结果表明：灰砂比为1:4和1:6的金属矿山全尾砂胶结充填体试块放置14 d后分别被6种水样浸泡90 d后均不会使地下水中重金属含量增加,且含量均低于《地下水质量标准》(GB/T 14848-93)Ⅲ类标准规定的含量限值,不会对生产、生活用水产生不良影响,故其用于井下空区充填是完全可行的。     

污水厂污泥中类二噁英类物质污染水平的研究进展

污水厂污泥的农业资源化利用是污泥处置的重要方法之一,但污泥中所含有毒有害的类二噁英类物质会制约污泥的农业利用.本文综述了污水厂污泥中类二口恶英类物质的污染水平和特点,为进一步制定和完善我国农用污泥中类二口恶英类物质控制标准提供科学的依据.     

压力交换式能量回收器在反渗透海水淡化技术中的应用

在反渗透海水淡化系统中，高压系统中采用压力交换式能量回收器，大大地降低海水淡化的能耗。压力交换式能量回收器的能量回收效率达到95％以上，本文从其工作原理和反渗透海水淡化设计上阐述其应用的优点。     

樟树叶片提取物抑菌作用研究

通过制备樟树叶片提取物及该提取物对霉菌与细菌的抑制作用的研究，结果表明樟树叶片（脂溶性）抑菌物比（水溶性）抑菌物的抑菌效果强，且（脂溶性）抑菌化合物对霉菌（青霉、曲霉、根霉）的抑制效果比细菌（大肠杆菌、枯草芽孢杆菌）强。     

Preparation of heat‐resistant gradient‐index polymer optical fiber rods based on poly(N‐isopropylmaleimide‐co‐methyl methacrylate)

Using the interfacial gel polymerization method, a heat‐resistant gradient‐index polymer optical fiber (GI POF) was developed based on the copolymer of methyl methacrylate (MMA) and N‐isopropylmaleimide (IPMI) as the matrix material and bromobenzene (BB) as dopant. The gradient distribution of IPMI in the GI POF rod was determined by element analysis. IPMI had great advantage in improving glass transition temperature (T_g) and forming a gradient‐index profile. There was a significant enhancement in the heat‐resistant property in comparison with a conventional GI POF rod. The combination of high thermal stability and easy fabrication makes the novel BB–IPMI–MMA system very suitable for heat‐resistant GI POF. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 280–283, 2003     

Ultrafast-laser-treated poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) electrodes with enhanced conductivity and transparency for semitransparent perovskite solar cells

Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is an important organic electrode for solution-processed low-cost electronic devices. However, it requires doping and post-solvent treatment to improve its conductivity, and the chemicals used for such treatments may affect the device fabrication process. In this study, we developed a novel route for exploiting ultrafast lasers (femtosecond and picosecond laser) to simultaneously enhance the conductivity and transparency of PEDOT:PSS films and fabricate patterned solution-processed electrodes for electronic devices. The conductivity of the PEDOT:PSS film was improved by three orders of magnitude (from 3.1 to 1024 S·cm^–1), and high transparency of up to 88.5% (average visible transmittance, AVT) was achieved. Raman and depth-profiling X-ray photoelectron spectroscopy revealed that the oxidation level of PEDOT was enhanced, thereby increasing the carrier concentration. The surface PSS content also decreased, which is beneficial to the carrier mobility, resulting in significantly enhanced electrical conductivity. Further, we fabricated semitransparent perovskite solar cells using the as-made PEDOT:PSS as the transparent top electrodes, and a power conversion efficiency of 7.39% was achieved with 22.63% AVT. Thus, the proposed route for synthesizing conductive and transparent electrodes is promising for vacuum and doping-free electronics.     

Guaranteed cost distributed fuzzy observer‐based control for a class of nonlinear spatially distributed processes

The guaranteed cost distributed fuzzy (GCDF) observer‐based control design is proposed for a class of nonlinear spatially distributed processes described by first‐order hyperbolic partial differential equations (PDEs). Initially, a T–S fuzzy hyperbolic PDE model is proposed to accurately represent the nonlinear PDE system. Then, based on the fuzzy PDE model, the GCDF observer‐based control design is developed in terms of a set of space‐dependent linear matrix inequalities. In the proposed control scheme, a distributed fuzzy observer is used to estimate the state of the PDE system. The designed fuzzy controller can not only ensure the exponential stability of the closed‐loop PDE system but also provide an upper bound of quadratic cost function. Moreover, a suboptimal fuzzy control design is addressed in the sense of minimizing an upper bound of the cost function. The finite difference method in space and the existing linear matrix inequality optimization techniques are used to approximately solve the suboptimal control design problem. Finally, the proposed design method is applied to the control of a nonisothermal plug‐flow reactor. © 2013 American Institute of Chemical Engineers AIChE J, 59: 2366–2378, 2013     

The cytotoxicity evaluation of magnetic iron oxide nanoparticles on human aortic endothelial cells

One major obstacle for successful application of nanoparticles in medicine is its potential nanotoxicity on the environment and human health. In this study, we evaluated the cytotoxicity effect of dimercaptosuccinic acid-coated iron oxide (DMSA-Fe₂O₃) using cultured human aortic endothelial cells (HAECs). Our results showed that DMSA-Fe₂O₃ in the culture medium could be absorbed into HAECs, and dispersed in the cytoplasm. The cytotoxicity effect of DMSA-Fe₂O₃ on HAECs was dose-dependent, and the concentrations no more than 0.02 mg/ml had little toxic effect which were revealed by tetrazolium dye assay. Meanwhile, the cell injury biomarker, lactate dehydrogenase, was not significantly higher than that from control cells (without DMSA-Fe₂O₃). However, the endocrine function for endothelin-1 and prostacyclin I-2, as well as the urea transporter function, was altered even without obvious evidence of cell injury in this context. We also showed by real-time PCR analysis that DMSA-Fe₂O₃ exposure resulted in differential effects on the expressions of pro- and anti-apoptosis genes of HAECs. Meanwhile, it was noted that DMSA-Fe₂O₃ exposure could activate the expression of genes related to oxidative stress and adhesion molecules, which suggested that inflammatory response might be evoked. Moreover, we demonstrated by in vitro endothelial tube formation that even a small amount of DMSA-Fe₂O₃ (0.01 and 0.02 mg/ml) could inhibit angiogenesis by the HAECs. Altogether, these results indicate that DMSA-Fe₂O₃ have some cytotoxicity that may cause side effects on normal endothelial cells.