一种微型FAIMS传感器芯片的研制

基于微机电系统(MEMS)技术,研制了一种微型高场非对称波形离子迁移谱(FAIMS)传感器芯片.芯片尺寸为18.8mm×12.4mm×1.2mm,由离子化区、迁移区、离子检测区组成.采用真空紫外灯离子源在大气压环境下对样品进行离子化,经过离子化区中聚焦电极的电场作用,实现离子在进入迁移区之前的聚焦,提高离子信号的强度.通过在上下玻璃上溅射Au/Cr(300nm/30nm)金属,并与厚度为200μm、采用感应耦合等离子体(ICP)工艺刻蚀的硅片键合,形成迁移区的矩形通道,尺寸为10mm×5mm×0.2mm.离子检测区为三排直径200μm、间距100μm交错排列的圆柱阵列式微法拉第筒,能同时检测正负离子.采用频率为2MHz,最大电压为364V,占空比为30%的高场非对称方波电压进行FAIMS芯片实验.以丙酮和甲苯为实验样品,载气流速80L·h-1,补偿电压从-10V到3V以0.1V的步长进行扫描,得到了丙酮和甲苯的FAIMS谱图,验证了FAIMS芯片的性能.丙酮和甲苯的FAIMS-MS实验进一步表明FAIMS系统实现了离子分离和过滤功能.     

射频电场幅值对高场非对称波形离子迁移谱检测对二甲苯的影响

高场非对称波形离子迁移谱(FAIMS)是一种利用非对称电场对气相分子进行分离检测的高灵敏度快速检测技术,超高的非对称波形电场是其迁移区的核心,非对称射频电场的幅值显著影响FAIMS的检测性能.实验以对二甲苯为样品,分析了非对称射频电场幅值对FAIMS检测性能的影响,实验表明随着射频电场幅值增大,检测灵敏度降低而分辨率增...     

利用芯片式高场非对称波形离子迁移谱技术快速检测苯丙氨酸

采用金属扩散管-芯片式高场非对称波形离子迁移谱(FAIMS)技术对苯丙氨酸进行了快速检测,设定测试压强为250 kPa,金属扩散管温度为190℃,在优化的最佳分析条件下,即:载气流速为2000 mL/min,分离电压为152.8 V时,在正模式下获得了苯丙氨酸的离子特征谱图和补偿电压特征值-0.62 V.另外,利用FAIMS对不同浓度的苯丙氨酸样品气进行了检测,确定了FAIMS检测的定量线性范围为6～20 mg/L和检出限为5.9 mg/L.本实验为FAIMS应用于苯丙氨酸的快速检测提供了重要参考.     

基于两维扫描高场不对称离子迁移谱技术检测挥发酚

要采用自制高场不对称波形离子迁移谱(FAIMS)仪对苯酚、2-甲酚、3-甲酚、4-甲酚以及2,4-二氯酚进行检测,通过结合补偿电压以及射频高压的二维扫描优化了对检测物的分辨.射频高场强度为1.6×104 V/cm时,2-甲酚与4-甲酚有最佳分辨效果,其余物质在高场强度大于1.8×104 V/cm时可以得到最佳分辨.研究...     

基于水分掺杂的高场非对称波形离子迁移谱检测硫化氢的研究

高场非对称波形离子迁移谱(FAIMS)是一种芯片级高灵敏度快速分析检测技术,其在大气压环境下工作的特点使之受环境影响明显,其中气体的湿度是显著影响因素,湿度的变化可引起迁移区离子反应机理以及迁移过程的变化。该文研究了干燥条件下痕量硫化氢的定量检测方法,确定了DF=33%时的检测线性范围与回归方程。利用PTFE管渗透作用,设定水浴温度为40～90℃,考察了不同含量水分对FAIMS检测硫化氢的影响。通过考察不同湿度下硫化氢的FAIMS特征谱图以及特征离子峰,研究了掺杂水分对于硫化氢谱峰峰值、补偿电压以及检测分辨率的影响。结果表明,FAIMS对于硫化氢的检测谱图清晰可见,能够准确定位其特征离子峰。随着气体中水分增多,不同分离电场下的产物离子峰峰值增大,说明湿度增大在一定程度上提高了灵敏度,DF=35%时的检出限为1.43×10~(-3) mg/m~3。     

利用高场非对称波形离子迁移谱技术快速鉴别降糖中药中的西药成分

为了快速检测降糖中成药中非法添加的西药成分,本研究采用热解吸-高场非对称波形离子迁移谱(FAIMS)技术扫描对比中成药降糖胶囊与对照标准品盐酸二甲双胍、盐酸苯乙双胍和格列本脲的图谱。设定热解吸管的加热温度为160℃,测试压强为107 kPa,电场强度范围设定为仪器最大电场强度的0~100%,补偿电压范围为"6~+6 V。实验中对3种标准品及其组合的谱图建立了含有补偿电压(CV)值、电场强度(E/N)值和电流强度(A I)3个变量的8组指纹识别点。结果表明,供试品与3种对照品混合物的图谱一致。经液相色谱比对实验验证,供试品中含有盐酸二甲双胍、盐酸苯乙双胍和格列本脲。本研究提出了一种基于FAIMS技术快速检测降糖中成药中非法添加西药成分的新方法。     

芯片级高场非对称波形离子迁移谱技术检测危险品

建立了吸气法-芯片级高场非对称波形离子迁移谱(FAIMS)技术,设置进样温度为50℃,载气与样品气流量分别为1500和100 mL/min时,测定了10种国家交通部门规定严禁携带的易燃易爆危险品。实验结果表明,利用FAIMS技术可以有效检测多种危险品。实验得到了10种危险品的FAIMS图谱,并对其进行了指纹识别。利用扩散管辅助技术得到10种物质的检测浓度范围约为0.1～20 mg/L。此方法方便快速,灵敏度高,具有很好的应用前景。     

高场不对称波形离子迁移谱快速检测水样中苯含量

建立了高场不对称波形离子迁移谱(FAIMS)检测水中苯含量的分析方法。研究了不同分离电压(Dispersion voltage,DV)下的苯标准谱图,获得用于苯识别的非线性函数二阶α2及四阶α4系数值分别为-3.8×10-5Td-2和5.1×10-8Td-4;通过平衡灵敏度与分离度,得到用于苯识别的最佳分离电压为800 V;通过不同质量浓度(0.08~0.64 mg/L)的苯样品与苯离子信号强度的关系,确定高场不对称波形离子迁移谱(FAIMS)对水中苯的检出限为0.89μg/L,远优于国家饮用水中苯浓度的限值10μg/L。本研究为水中苯检测提供了一种快速、高灵敏的方法。     

载气流速对高场不对称波形离子迁移谱的影响

载气流速是影响高场不对称波形离子迁移谱(FAIMS)的重要参数.以自制的高场不对称波形离子迁移谱仪为实验平台,在射频电场幅值3 kV/cm,频率500 kHz,占空比0.36的条件下,研究了载气流速对苯离子迁移谱谱峰强度和半峰宽的影响.实验结果表明: 载气流速为3.7 L/min时,苯样品的谱峰强度最大,仪器的灵敏度最高.随着载气流速的增加,谱峰半峰宽变宽,仪器的分辨率下降.载气流速为3 .0～3.7 L/min时仪器综合性能最佳.此结果对于控制迁移谱仪载气流速有重要的参考意义.     

热解析-高场非对称波形离子迁移谱(FAIMS)技术快速检测合成色素

采用热解析-高场非对称波形离子迁移谱(FAIMS)技术快速检测柯衣定、 孔雀石绿、 罗丹明B和甲基红4种合成色素. 通过对热解析温度和载气流量进行优化, 确定了不同色素的离子特征信号. 在最佳分析条件下, 热解析温度为160 ℃, 载气流量为1.6 L/min, 采用不同模式下补偿电压(CV)值定性, 以FAIMS在正模式下检测柯衣定(CV=0.41 V)和罗丹明B(CV=-0.89 V), 在负模式下检测甲基红(CV=-0.67 V)和孔雀石绿(CV=0.02 V); 用外标法定量检测了样品中的4种合成色素, 线性关系R²≥0.9967, 检出限为2.5~10 μg/L, 定量限为5~20 μg/L, 加标回收率≥78.2%, 相对标准偏差RSD≤8%. 本文为FAIMS技术快速检测合成色素提供了一定的技术基础.     

Dichroism of absorption and polarization of phosphorescence of molecules of the closed form of nitrobenzospirothiopyran

The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.     

Synthesis of phenolic components of Grains of Paradise

Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.     

非那雄胺合成工艺改进

非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。     

Study of hydration of two cements of different strengths

Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, M_o, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700^oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.     

Determination of heats of detonation and influence of components of composite explosives on heats of detonation of high explosives

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

     

Investigation of Kinetics of Solid-Phase Synthesis of Lithium Orthosilicate

The kinetics of the interaction between lithium carbonate and silica with various degrees of dispersion was investigated by TG and DTA methods. It was found that the utilization of pyrogenic silica with a specific surface area of about 300 m²g^-1 instead of aerosil with one of 175 m²g^-1 leads to an increase of the reaction rate between lithium carbonate and silica, which depends on the formation and growth of lithium orthosilicate crystals in the first stage, and is conditioned by the diffusion of lithium and oxygen ions through the lithium orthosilicate layer formed at temperatures above 800 K. This supposition is supported by the kinetic analysis results obtained with the use of the different models. The optimal regime of heating is recommended. This revised version was published online in July 2006 with corrections to the Cover Date.     

小环化合物中饱和碳质子化学位移的计算

小环化合物由于其张力、构型、构象和各向异性效应等原因,环碳上质子化学位移缺乏规律性,难以预测,对此作者曾提出一种近似算法。本文根据303种小环化合物中饱和碳质子的化学位移实验数据,将适于计算这类质子化学位移的公式表述为:     

恶臭嗅辨实验室建设探讨

针对恶臭测试的环境影响问题,提出了解决的实例方案,并对方案的要点及优缺点进行讨论,此方案在实际操作中具有较好的效果。     

Summary of development of the theory of stability of colloids and thin films

In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.