Electrochemical preparation and characterization of three-dimensional nanostructured Sn2S3 semiconductor films with nanorod network

Three-dimensional (3D) nanostructured Sn₂S₃ semiconductor films have been prepared on ITO-coated glass substrates by potentiostatic electrodeposition at −0.80 V (vs. SCE) from a novel plating bath containing K₄P₂O₃ as a complexing agent and Na₂SO₃ as a stabilizing agent and by subsequent annealing. Results showed that the annealing drove the as-deposited Sn₂S₃ films to grow from a granular structure into a nanorod network structure. The nanorods were around 50-100 nm in diameter and 1000 nm in length. The band gap of the annealed film was 1.65 eV and the conductivity was n type. The carrier mobility achieved up to 20.5 cm² V⁻¹ s⁻¹ due to the direct electrical pathways provided by the nanorod network.     

Geopolymerisation of a silica-rich tailing

A silica-rich tailing from vanadium extraction has been used for geopolymer synthesis in combination with metakaolin (MK) as an additional-Al source. Results show that alkaline roasting pretreatment effectively enhance geopolymerisation ability of the tailing in terms of XRD analysis and leaching tests. Strengths of samples can be improved by adding proper quantities of MK, or appropriately raising curing temperature. Curing temperature also affects the Si/Al ratio since higher curing temperature is more favorable for releasing Al. The highest compressive strength of 55.7 MPa can be obtained.     

Influence of imidazolium-based ionic liquids on the performance of polyaniline-CoFe2O4 nanocomposites

Using cobalt ferrite (CoFe₂O₄) nanoparticles of different content as nucleation sites, polyaniline-CoFe₂O₄ nanofiber composites were successfully synthesized at the interface of water and ionic liquid via in-situ polymerization. Structure and morphology were investigated by TGA, TEM, XRD, and FT-IR. The influence of ionic liquids on the structure, conductivity and magnetic property of polyaniline-CoFe₂O₄ nanocomposites were studied in detail. The results show that imidazolium-based ionic liquids BMIPF₆ acts as an anchor agent during the nanofiber composites formation process. Introduction of ionic liquids obviously improves the conductivity but weakens the magnetization of polyaniline-CoFe₂O₄ nanocomposites in the same [CoFe₂O₄]/[An] ratio.     

Composite membranes based on a novel benzimidazole grafted PEEK and SPEEK for fuel cells

Poly(ether ether ketone) (PEEK) and sulfonated poly(ether ether ketone) (SPEEK, IEC = 2.07 mequiv.g⁻¹) have been synthesized via nucleophilic aromatic substitution reaction. Bromomethylated poly(ether ether ketone) (PEEK-Br) is then prepared and reacted with 2-benzimidazolethiol to obtain the benzimidazole grafted poly(ether ether ketone) (PEEK-BI). The structures of PEEK-Br and PEEK-BI are characterized by ¹H NMR spectra. Composite membranes based on SPEEK and PEEK-BI are prepared and their properties used for fuel cells are studied in detail. The results show that the composite membranes exhibit greatly improved mechanical properties as well as reduced water uptake and methanol permeability compared with the pristine SPEEK membrane. The increased oxidative stability and selectivity indicate that the composite membranes are promising to be used as proton exchange membranes.     

室内空气质量的研究现状及展望

本文通过大量文献调研，详细论述了当前国内外室内空气质量的研究现状和展望，室内空气污染的特点，以及室内空气污染的污染源和污染物，同时也论述了控制室内空气污染采取的措施和方法。     

High anticorrosion chromate-free passive films made by Titanate and waterborne polyurethane on galvanized steel sheet

In this study, environmental friendly hybrid passive films on galvanized steel sheet were prepared from waterborne polyurethane and Titanate. The experimental results show that the optimized composition in passive solution was 30 g/L TiOSO₄, 5 g/L (NH₂)₂CS, 10 g/L NH₄F and 150 g/L WPU. The samples were dipped into passive solution for 10 s, dried at 120 °C for 15 s. Though the film's thickness is just 0.5 μm, the white rust resistance is excellent.     

Novel SnO2/MnO co-doped phosphate glasses with tunable luminescence properties

In the present work, novel SnO₂/MnO co-doped phosphate glasses are prepared and their tunable luminescence properties are presented. Under excitation at 267 nm, all co-doped glasses exhibit an assembly of SnO₂ blue emission at 420 nm and MnO red emission around 600 nm. With the increasing of MnO concentration, intensity of the SnO₂ blue emission decreases while that of MnO red emission increases. With the increasing of SnO₂ concentration, both SnO₂ and MnO emissions are greatly enhanced, resulting in the white light emitting.     

皮带给矿机减速器的模糊优化设计

针对常规的优化设计难以反映产品运行的真实工况，影响优化设计的效果，建立了圆柱齿轮减速器模糊优化的数学模型，并对实例进行了计算和分析     

高碱性合成磺酸钙清净剂的研制

研究了以重烷基苯磺酸为原料制备高碱性合成磺酸钙清净剂的合成工艺，合成磺酸钙的中试研究考察了实验室合成工艺的可行性。在对影响中和反应和碳酸化反应的各类因素进行研究的基础上确定了工艺路线和条件，制备出总碱值大于295的产品，所得产品的理化指标、模拟评定结果都达到了国内外同类产品水平。为工业试验和工业生产提供了必要的依据。     

基于高效假轨迹的隐私保护算法研究

为了解决LBS服务中用户轨迹隐私泄露的问题,提出了一种基于高效假轨迹的隐私保护算法。首先,该方案综合考虑用户所处区域的背景信息,以划分网格的方式,统计每个网格的历史服务请求概率,确保生成的每一个假位置与对应真实位置具有相同的历史服务请求概率;其次,结合网格历史服务请求概率并通过万有引力定律模型计算出用户位置转移概率;最后,生成与真实位置转移概率最相近的k-1条假轨迹实现K-匿名。实验结果表明,该方案能够更有效地保护用户的轨迹隐私。