基于拖拉机姿态特征的意象认知研究

目的 挖掘拖拉机姿态与意象偏好的关系,进而指导拖拉机的造型设计。方法 采用多元尺度分析法和聚类分析法筛选拖拉机的姿态样本;运用形态分析法分解并标定典型样本的姿态特征,通过语词聚类实验构建拖拉机姿态的意象空间;结合语义差分法和问卷调研获取用户对典型拖拉机样本的意象偏好,运用灰色关联分析法得到拖拉机姿态特征与意象的关联。结果 得到拖拉机的8个典型姿态样本,获取了拖拉机姿态的四个语义维度下的五个代表性语义词对。明确了拖拉机姿态的特征框架和语义结构,归纳得到拖拉机姿态的意象认知规律。结论 拖拉机的姿态特征蕴含着意象信息,研究结果可以为设计师解读用户的意象认知提供参考。     

Microstructure and Wear Resistance of Laser Clad Cobalt- based Composite Coating on TA15 Surface

利用横流CO2激光器在TA15钛合金表面通过优化的激光熔覆工艺制备出原位自生的多种颗粒增强钴基复合涂层,以增强表面的耐磨性和硬度。利用X射线衍射(XRD)、金相、扫描电镜(SEM)、硬度测试机和磨损试验机等方法对熔覆层进行分析。结果表明,熔覆层的显微结构主要由γ-Co、α-Ti固溶体和弥散分布的原位自生TiB2,、Cr5Si3,、TiC、WB、SiC、Co3Ti、NiC颗粒组成,这些多种颗粒增强相弥散分布在细小的树枝晶组织之间。熔覆层的显微硬度比基体提高很多,HV达到10000 MPa左右,约为基体硬度的3倍。与钛合金相比,熔覆层的耐磨性也有显著提高,其磨损率约为钛合金的1/12。熔覆层的磨损机理具有粘着磨损和磨粒磨损的混合特征。     

响应面优化超声辅助提取莲子心总生物碱工艺

利用响应面分析法对超声辅助提取莲子心中总生物碱的工艺条件进行优化。在单因素实验、Plackett-Burman实验设计和最陡爬坡实验的基础上,以莲子心总生物碱提取量为响应值,利用效应响应面法研究各因素及其交互作用对莲子心总生物碱提取量的影响,优选莲子心中总生物碱的提取工艺。作者采用非线性数学模型拟合的方式,使自变量和因变量的关系扩展到曲面,从而使实验数据更加精密。实验优化得出超声辅助提取莲子心总生物碱的最佳工艺条件为:料液质量体积比1 g∶40.4 mL,乙醇体积分数64.4%,超声提取时间40 min,模型预测可达到128.695 mg/g。在上述条件下,莲子心总生物碱的提取率可以达到128.673 mg/g,与模型预测值基本一致。     

九江市赛城湖健康评价研究

以九江市赛城湖为研究对象,结合江西省湖泊健康问题的现状与特点,构建了水文水资源、物理结构、化学、生物及社会服务功能五大准则层的评价指标体系,通过采样监测与资料调查分析,对2021年赛城湖健康状况进行评价。结果表明：（1）赛城湖的综合健康指数为79.25,湖泊健康状况为良好,虽然功能有一定程度受损,但仍处于可持续发展的健康状况。（2）赛城湖的水文水资源和物理结构方面的赋分均为满分;社会服务功能方面的赋分为85.49分;生物完整性方面的赋分为74.76分;化学方面的赋分为52.86分。（3）赛城湖的“EI营养状态指数”和“底泥重金属污染状况”两个指标是赛城湖整体健康状况的主要影响因子。研究结果可为九江市的生态文明建设及江西省其他地方开展河湖健康调查评价工作提供参考。     

Enhanced proton conduction in zirconium phosphate/ionic liquids materials for high-temperature fuel cells

This work reports the synthesis of high temperature proton conductors based on zirconium phosphate and imidazolium-based ionic liquids. This material is evaluated for high temperature proton exchange membrane fuel cells applications operating at 200 °C. The characterization results show high proton conductivity, enhanced water uptake properties, changes in structure, and exfoliation in zirconium phosphates crystal layers upon the introduction of the ionic liquid. The proton conductivity results demonstrate that there is an optimum amount of ionic liquid that can be introduced into zirconium phosphates to enhance its conductivity beyond which, the conductivity starts to decrease. At the optimum conditions, the addition of ionic liquids enhances the proton conductivity of the zirconium phosphates material by orders of magnitude. The results show a high proton conductivity the order of 10^?2 S cm^?1 at room temperature and high anhydrous proton conductivity of 10^?4 S cm^?1 at 200 °C. These findings indicate that the zirconium phosphate-ionic liquid material has a great potential as solid proton conductors for fuel cells applications operating at elevated temperatures.     

乳酸菌对果蔬产品的抑菌机理及应用

随着人们对健康饮食的日益重视,果蔬产品作为重要的营养来源备受关注。然而,果蔬的保藏一直是个难题,传统的果蔬保鲜剂往往依赖于化学物质,其在提高保鲜效果的同时却也带来了潜在的风险和不良影响,因此在果蔬生产和分销链中开发绿色有效的抗菌剂成为研究热点。近年来,利用乳酸菌来延缓果蔬腐败进程已引起研究人员的极大兴趣。乳酸菌可以减缓果蔬腐败,且没有重大不良反应,其作为果蔬防腐剂的应用潜力巨大。然而,乳酸菌的抑菌机理不明确,而且获得监管机构批准并可广泛用于商业用途的乳酸菌或其代谢产物数量仍然很少,导致其在果蔬保鲜贮藏中的应用还不够广泛。本文综述乳酸菌的抑菌机理、应用现状以及在抑制腐败菌方面的优势和局限性,总结近年有关乳酸菌作为果蔬产品抑菌剂的研究进展,并对乳酸菌的发展进行展望,为乳酸菌在果蔬保鲜中的应用提供理论依据。     

Organoclays assisted vat and disperse dyeing of poly(ethylene terephthalate) nanocomposite fabrics via melt spinning

Polyethylene terephthalate nanocomposites containing six modified montmorillonite nanoclays were prepared by a melt compounding technique. The effect of intercalated compounds of montmorillonite on textile mechanical properties of resultant polyethylene terephthalate nanocomposite fabrics was investigated. Winding was not possible, when the polymers were first compounded with the desired amount of montmorillonite and then spun, as filament breakage occurred. Spinable polymer were only obtained by mixing polyethylene terephthalate master batches with 4 wt% montmorillonite, which contained tallow intercalating compound with pure untreated polyethylene terephthalate to a montmorillonite content of 0.5 wt%, thus decreasing the concentration of thermally degraded polymer chains. After spinning the fibres were drawn and knitted into fabric samples for further testing. The prepared polyethylene terephthalate nanocomposite fabrics using montmorillonite exhibited higher colour strength using vat and disperse dyes compared with those of the reference fabrics made from fibres spun without montmorillonite clay content and regular fabrics. The carbocyclic‐based vat dyes have higher colour strength values on polyethylene terephthalate nanocomposite fabrics if compared with heterocyclic‐based vat dyes. The colour fastness ratings for both vat and disperse dyeings secured very good to excellent washing and perspiration fastness on polyethylene terephthalate nanocomposite fabrics. All dyed fabrics showed excellent light fastness using vat and disperse dyes. The preparation of polyethylene terephthalate nanocomposite fabrics with improved textile mechanical and vat dyeing properties needs further investigations.     

Influence of the Nd3+ ions content on the FTIR and the visible up-conversion luminescence properties of nano-structure BaTiO3, prepared by sol–gel technique

The nano-structure BaTiO₃ (BT) powder doped with different concentrations of Nd³⁺ ions were annealed at 750 °C for 1 h to form nano-structure tetragonal phase of BT powder. The structure properties studied using XRD and FTIR methods. Sensitized up-conversion luminescence observed under excitation of 808 nm diode laser, suggesting that the Nd³⁺ ions-doped BT might be an ideal up-conversion material for infrared excitation. The influence of increasing the concentration of the Nd³⁺ ions on the luminescence intensity investigated using laser diode. The up-conversion mechanisms in the doped system will be discussed by analyzing the energy level structures of the Nd³⁺ ions.     

Structure and electrical properties of ZnO doped barium-metaphosphate glasses

The zinc–barium–metaphosphate glasses (ZBP) with composition of (50 − x)BaO–xZnO–50P₂O₅; (0 ≤ x ≤ 50 mol %), have been successfully prepared. The influences of the amount of ZnO on the structure, physical and chemical properties, and crystallization behavior of the glasses were investigated using Fourier transform infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC), X-ray diffraction and energy dispersive X-ray techniques (XRD/EDX). The density and the glass transition temperature (T_g) of glass were measured using Archimedes' method and differential thermal analysis (DTA). The FTIR analysis revealed a shortening of the phosphate chains by the shift of (P–O–P)_as band to higher wave number owing to the substitution ZnO of BaO. The amount of ZnO was further increased, [ZnO4] tetrahedra were formed and ZnO acted as a glass network former, integrating the phosphate glass network. The density, chemical stability and the activation energy of crystallization of the glasses increased with the amount of ZnO, whereas the glass transition temperature decreased. The dc- and ac-conductivity were measured. The results obtained from ac-conductivity reveals that the values of σ(ω) increases on increasing frequency and it is also increases on increasing the ZnO content level. The dc-conductivity of all the glasses increases with an increase in temperature. The dielectric permittivity (?′) and loss factor (?″) were calculated in the frequency range of 50 Hz–1 MHz. The dipolar relaxation occurred between 10⁵–10⁶ Hz. Finally, the dielectric strength (Δ?) and the relaxation time (τ) were estimated.     

Universal access to information services—the need for user information and its relationship to device profiles

Users access information services with a variety of devices and with different interaction modes that depend on personal characteristics (including disabilities) and on the context of usage. With the appearance of mobile devices, the industry has focused its efforts on the standardization of device characteristics, thus giving to information providers some content adaptation facilities. However, little attention has been paid to the standardization of user profiles that will allow further customization and adaptation capabilities in mainstream services. This paper will present the authors experiences in outlining and implementing user profiles, as well as possible integration paths with device characteristics.