用AT89C51单片机和MAX505 DAC研制的程控信号源

本文介绍了用单片机AT89C51和MAX505 DAC制作程控信号源的原理,并在其中对AT89C51单片机和MAX505 DAC的工作原理及特性,怎样用单片机的中断控制和串行接口控制作为重点给予了阐述。     

图像处理技术在低逸出功印刷型FED中的应用

采用低成本、大面积、低逸出功FED阴极材料及其阴极浆料,研制了大面积印刷式FED(样机),具有自主知识产权,在国内外属首创。介绍了低逸出功可印刷型场致发射显示系统的工作原理、数字视频图像的转换和处理、视频数据的传输、列灰度驱动和行驱动集成电路以及FPGA控制技术等。为了改善场致发射显示器的显示效果,通过理论分析和实际验证提出了亮度非均匀性校正、γ校正、自动功率控制等相应的解决方案。将图像处理技术应用到驱动电路中,改善了图像的亮度均匀性和灰度再现质量,降低了整机的功耗。首次将本技术应用于大屏幕低逸出功印刷型63.5cm(25英寸)VGA级彩色FED驱动系统中,研制出了能显示彩色视频图像的彩色FED显示器样机。亮度达400cd/m2、对比度为1000∶1,电路灰度等级为256级。     

Development of Improved High-Performance Liquid Chromatography Method for the Determination of Residual Caprylic Acid in Formulations of Human Immunoglobulins

Quality control of human immunoglobulin formulations produced by caprylic acid precipitation necessitates a simple, rapid, and accurate method for determination of residual caprylic acid. A high-performance liquid chromatography method for that purpose was developed and validated. The method involves depletion of immunoglobulins, the major interfering components that produce high background noise, by precipitation with acetonitrile (1:1, v/v). Chromatographic analysis of caprylic acid, preserved in supernatant with no loss, was performed using a reverse-phase C18 column (2.1 × 150 mm, 3 μm) as a stationary phase and water with 0.05% TFA–acetonitrile (50:50, v/v) as a mobile phase at a flow rate of 0.2 mL/min and run time of 10 min. The developed method was successfully validated according to the ICH guidelines. The validation parameters confirmed that method was linear, accurate, precise, specific, and able to provide excellent separation of peaks corresponding to caprylic acid and the fraction of remaining immunoglobulins. Furthermore, a 2⁴⁻¹ fractional factorial design was applied in order to test the robustness of developed method. As such, the method is highly suitable for the quantification of residual caprylic acid in formulations of human immunoglobulins for therapeutic use, as demonstrated on samples produced by fractionation of convalescent anti-SARS-CoV-2 human plasma at a laboratory scale. The obtained results confirmed that the method is convenient for routine quality control.     

透平叶栅三维粘性气动反问题的控制理论方法

将基于控制理论的形状优化设计方法应用于粘性可压流动条件下的透平叶栅三维气动反设计,详细推导了三维N-S方程伴随系统的偏微分方程组及其各类边界条件.讨论了伴随系统的解的适定性条件,并由此给出应用N-S方程进行气动优化的目标函数的选取限制.研究了伴随方程的数值求解技术,给出敏感性导数的最终计算式,结合拟牛顿算法发展了三维透平叶栅粘性反问题的气动设计方法.     

一维光子晶体热辐射光谱控制模拟研究

将一维金属-介质光子晶体应用于热辐射光谱控制,基于电磁波理论建立了光谱能量关系和光谱特性计算方法.采用钨(W)和二氧化硅(SiO2)设计了一维金属-介质光子晶体,从麦克斯韦方程组出发,研究了该一维结构的光谱特性.研究结果表明,该结构能够有效地结合材料自身光谱属性和光子晶体的光谱控制特性实现热辐射光谱特性的选择控制,可被用于热光伏系统实现热辐射光谱控制.     

红外光谱法直接鉴别苦丁茶的研究

本文利用傅立叶变换红外光谱(FTIR)法快速、直接地测定了11种苦丁茶,并对所获得的指纹图谱进行特征峰指认和对比分析。结果表明:各种苦丁茶化学成分相同,而由于各成分间的相对含量的不同,使每种样品都有自己独特的红外谱图,不同产地、不同级别苦丁茶的红外吸收频率、吸收峰的相对强度都存在比较大的差异。同时还运用傅立叶变换红外光谱技术对不同产地、不同级别苦丁茶的混合化学体系进行了全组分快速分析,为苦丁茶的鉴别及质量控制提供了可靠的依据。     

Products of Photo- and Thermochemical Rearrangement of 19-Membered di-tert-Butyl-Azoxybenzocrown

The preparation and characterization of products of the photochemical and thermochemical rearrangements of 19-membered azoxybenzocrowns with two, bulky, tert-butyl substituents in benzene rings in the para positions to oligooxyethylene fragments (meta positions to azoxy group, i.e., t-Bu-19-Azo-O have been presented. In photochemical rearrangement, two colored typical products were expected, i.e., 19-membered o-hydroxy-m,m′-di-tert-butyl-azobenzocrown (t-Bu-19-o-OH) and 19-membered p-hydroxy-m,m′-di-tert-butyl-azobenzocrown (t-Bu-19-p-OH). In experiments, two colored atypical macrocyclic derivatives, one 6-membered and one 5-membered ring, bearing an aldehyde group (t-Bu-19-al) or intramolecular ester group (t-Bu-20-ester), were obtained. Photochemical rearrangement led to one more macrocyclic product being isolated and identified: a 17-membered colorless compound, without an azo moiety, t-Bu-17-p-OH. The yield of the individual compounds was significantly influenced by the reaction conditions. Thermochemical rearrangement led to t-Bu-20-ester as the main product. The structures of the four crystalline products of the rearrangement—t-Bu-19-o-OH, t-Bu-19-p-OH, t-Bu-20-ester and t-Bu-17-p-OH—were determined by the X-ray method. Structures in solution of atypical derivatives (t-Bu-19-al and t-Bu-20-ester) and t-Bu-19-p-OH were defined using NMR spectroscopy. For the newly obtained hydroxyazobenzocrowns, the azo–phenol⇄quinone–hydrazone tautomeric equilibrium was investigated using spectroscopic methods. Complexation studies of alkali and alkaline earth metal cations were studied using UV-Vis absorption spectroscopy. ¹H NMR spectroscopy was additionally used to study the cation recognition of metal cations. Cation binding studies in acetonitrile have shown high selectivity towards calcium over magnesium for t-Bu-19-o-OH.     

稀土化合物在高分子科学中的应用研究进展

综述了稀土化合物在高分子科学中的广泛应用:烯烃聚合/共聚合催化剂、聚氯乙烯的热稳定剂、填充改性聚合物和制备功能材料等,并涉及了笔者在稀土催化接枝改性领域的最新研究成果.     

锰卟啉/钒取代杂多酸配合物的合成、表征和性能研究

利用碘化四对(4-三甲氨基苯基)锰卟啉与钒取代杂多酸H5 PMo10 V2O40,在水溶液中,室温下反应合成了锰卟啉/钒取代杂多酸配合物,用红外和紫外光谱技术对其结构进行了表征,发现该配合物中包含着金属卟啉的环状结构与杂多酸的笼状结构,并且二者以化学键的形式键合在一起.以该化合物作为催化剂,以过氧化氢水溶液为氧化剂,在温和的条件下研究了锰卟啉/钒杂多酸配合物对苯的羟基化反应的影响,考察了催化剂的催化活性,探讨了催化剂对苯羟基化反应的活性中心.研究结果表明,杂多酸中的钒原子是其主要的催化活性中心,锰卟啉的存在可以有效地提高其催化活性.     

反射式红外传感器在智能型节水系统中的应用

利用反射式红外传感器和少量的电子器件(单稳态触发器),研制了智能型节水控制系统。该系统能够识别是否有人入厕,酌情产生冲洗信号, 躯动进水电磁阀开启,向浮球式水箱内注水,待注满足以冲刷干净所需的两水箱水后,便自动地切断电磁阀中电源,达到了既卫生又节约的目的。在某一教学楼应用该系统一年多来,与无使用此系统的同规模另一教学楼相比,节水约70％。该系统元件少、成本低、结构合理、工作可靠、安装容易、维修方便,有广阔的应用前景。