超声马达转子摩擦材料厚度对驱动性能的影响研究

制备了一系列不同厚度的摩擦材料 ,利用超声马达摩擦特性模拟试验装置 ,研究了摩擦材料厚度对超声马达空载转速和堵转力矩的影响 .基于一个简化的行波超声马达定子和转子接触模型 ,用有限元法计算了定子和转子接触变形随摩擦材料厚度的变化规律 ,提出了定子和转子具有合理接触变形的摩擦材料厚度范围 .根据试验和理论计算结果确定了摩擦材料最佳厚度 ,为超声马达摩擦材料厚度设计提供了理论依据     

1.315μm附近CO2的高分辨率吸收光谱

 利用可调谐激光长程吸收光谱测量系统，记录到1.315μm附近高气压（80kPa和40kPa）CO₂的高分辨率吸收光谱，拟合分析获得谱线参数，结果与HITRAN 2k的数据基本一致。用程差法测量了绝对吸收，氧碘激光频率(7 603.138 5cm^-1)的总吸收截面为(0.23~0.29)×^-24cm²。仅计算谱线吸收的吸收截面为0.18×10^-24cm²。在1.315μm波段COCO₂存在连续吸收，吸收截面为(0.05~0.11)×10^-24cm²。还讨论了测量误差问题。     

微分方程解的存在与惟一性的一种证明

运用Banach压缩定理可证明微分方程解的存在与惟一性.     

人力资源与区域经济发展分析

人力资源是实现区域经济发展的最重要条件之一，从已有的经济理论模型理论研究及本建立经济数学模型实证研究表明，人力资源数量，质量，结构，流动都影响区域经济发展，加快区域经济发展，必须加大教育投入，创造条件吸引人才，加强技术技能培训，增加第三产业作人力资源等。     

再谈应用数学的发展——对“试谈”的补充意见

本文采用校勘的格式对 [1]提出补充意见     

Quantitative determination of 15 bioactive triterpenoid saponins in different parts of Acanthopanax henryi by HPLC with charged aerosol detection and confirmation by LC–ESI‐TOF‐MS

Triterpenoid saponins are difficult to analyze using high‐performance liquid chromatography coupled to UV/vis spectrophotometry due to their lack of chromophores. This study describes the first analytical method for the determination of 15 triterpenoid saponins from the leaves, stems, root bark, and fruits of Acanthopanax henryi, using a high‐performance liquid chromatography with charged aerosol detection coupled with electrospray ionization mass spectrometry method. The separation was carried out on a Kinetex XB‐C18 column with an acetonitrile/water gradient as the mobile phase, followed by charged aerosol detection. The operating conditions of charged aerosol detection were set at 24 kPa for nitrogen pressure and 100 pA for the detection range. Liquid chromatography with electrospray ionization mass spectrometry is described for the identification of compounds in plant samples. The electrospray ionization mass spectrometry method involved the use of the [M + Na]⁺ and [M + NH₄]⁺ ions for compounds 1 – 15 in the positive ion mode with an extracted ion chromatogram. The developed method was fully validated in terms of linearity, sensitivity, precision, repeatability, and recovery, then subsequently applied to evaluate the quality of A. henryi.     

Technology of preparing anode films and the effect of co-sensitization in dye-sensitized solar cells

Nanocrystalline N–Zn/TiO₂ anode films were prepared by doping element N and Zn. These element-doped films have a better performance in dye-sensitized solar cell than the non-doped film. The test shows that the best thickness of N–Zn/TiO₂ anode film is 13.5 μm. UV–Visible measurements show that there is a complementarity in ultraviolet–visible absorbance range between P3OT and N719, both are used as dyes in this study, the former is prepared and the latter is commercially available. SEM shows a significant mass increase of anode film after treated with TiCl₄. Solar cells based on N–Zn/TiO₂ anode film with TiCl₄ treatment was firstly co-sensitized by N719/P3OT. A solar-to-electric energy conversion efficiency of 3.54 % was obtained. Compared with the traditional dye-sensitized solar cell, the photoelectric conversion efficiency, V _oc and J _sc have been increased.     

2-巯基苯并咪唑衍生物的设计、合成及抗肿瘤活性研究

为了从苯并咪唑类衍生物中寻找新的活性化合物,以溴乙酸作为起始原料,设计合成了17个2-巯基苯并咪唑衍生物4a～4q。采用噻唑蓝(MTT)法测试了目标化合物对人宫颈癌细胞(He La)、人乳腺癌细胞(MCF-7)、人肝癌细胞(HepG2)、人非小细胞肺癌细胞(A549)的增殖抑制活性。结果显示,大部分化合物具有较好的抗肿瘤活性,其中,((1H-苯并[d]咪唑-2-基)硫基)-1-(4-二苯甲基哌嗪-1-基)乙烷-1-酮(4l)对HepG2细胞的抑制活性最好,IC_(50)值为12. 62±0. 78μmol/L,接近于对照药品吉非替尼(9. 72±0. 38μmol/L)。此外,利用分子对接方法对目标化合物的构效关系进行了讨论。     

UNIPOL气相聚乙烯反应器块料生成热历史研究

本文采用热分析(DSC)的方法对UNIPOL气相流化床聚乙烯反应器块料生成过程所经历的热历史进行了详细测试与对比分析。结果发现,在反应器排产线性低密度聚乙烯LLDPE DFDA-7042时,DSC曲线上出现了多重熔融峰,其一次升温熔融峰值和熔融焓值均高于对应粉料的,表明块料经历了更为复杂的熔融再结晶过程,结晶更为完善;而在排产高密度聚乙烯HDPE DMDA-8007时,DSC曲线上只有一个完整的熔融峰,其一次升温熔融峰值和熔融焓值与对应粉料的基本相同,表明块料未经历复杂的熔融再结晶热历史过程。不同牌号块料经历的热历史不同,反映了其结块机理的不同。使用不同催化剂生产DFDA-7042时产生的块料均经历了复杂的熔融再结晶过程。通过对块料形成过程热历史的追溯,加深了对块料形成机理的认识。