无定形硒纳米粒子的交联酶模板法合成及其在生物传感器中的应用

本文以戊二醛交联的辣根过氧化物酶(HRP)为模板合成了均匀分散的无定形硒纳米粒子(粒径10~20 nm)，以所得合成产物为载体构建了HRP生物传感器。研究结果表明，无定形硒纳米粒子具有良好的生物相容性和吸附性，所得传感器灵敏度高，对测定底物的生物亲和性好。     

A New Predictive Equation for the Surface Tensions of Aqueous Mixed Ionic Solutions Conforming to the Linear Isopiestic Relation

The linear isopiestic relation has been used, together with the fundamental Butler equations, to establish a new simple predictive equation for the surface tensions of the mixed ionic solutions. This newly proposed equation can provide the surface tensions of multicomponent solutions using only the data of the corresponding binary subsystems of equal water activity. No binary interaction parameters are required. The predictive capability of the equation has been tested by comparing with the experimental data of the surface tensions for the systems HCl–LiCl–H₂O, HCl–NaClO₄–H₂O, HCl–CaCl₂–H₂O, HCl–SrCl₂–H₂O, HCl–BaCl₂–H₂O, LiCl–NaCl–H₂O, LiCl–KCl–H₂O, NaCl–KCl–H₂O, KNO₃–NH₄NO₃–H₂O, and LiCl–NaCl–KCl–H₂O at 298.15 K; KNO₃–NH₄Cl–H₂O, KBr–Sr(NO₃)₂–H₂O, NaNO₃–Sr(NO₃)₂–H₂O, NaNO₃ –(NH₄)₂SO₄–H₂O, KNO₃–Sr(NO₃)₂– H₂O, NH₄Cl–Sr(NO₃)₂–H₂O, NH₄Cl– (NH₄)₂SO₄–H₂O, KBr–KCl–H₂O, KBr–KCl–NH₄Cl–H₂O, KBr–KNO₃– Sr(NO₃)₂–H₂O, KBr–NH₄Cl–Sr(NO₃)₂–H₂O, KNO₃–NH₄Cl–Sr(NO₃)₂–H₂O, and NH₄Cl–(NH₄)₂SO₄–NaNO₃–H₂O at 291.15 K; and KBr–NaBr–H₂O at temperatures from 283.15 to 308.15 K. The agreement is generally quite good.     

Kinetics of hydrate formation using gas bubble suspended in water

An innovative experimental technique, which was devised to study the effects of temperature and pressure on the rate of hydrate formation at the surface of a gas bubble suspended in a stagnant water phase, was adapted in this work. Under such conditions, the hydrate-growth process is free from dynamic mass transfer factors. The rate of hydrate formation of methane and carbon dioxide has been systematically studied. The measured hydrate-growth data were correlated by using the molar Gibbs free energy as driving force. In the course of the experiments, some interesting surface phenomena were observed.     

A New Predictive Equation for the Depression in Freezing Points of Multicomponent Aqueous Solutions Conforming to the Linear Isopiestic Relation

The linear isopiestic relation has been used together with a well-known thermodynamic equation to establish a new predictive equation for freezing point depression. This equation can provide predictions for multicomponent solutions conforming to the linear isopiestic relation using only information on the corresponding binary subsystems. The predictive capability of the equation has been tested by comparing with the experimental data at 25°C reported in the literature and particularly those of Pathwardhan and Kumar. The systems used are NaCl—MgCl₂—H₂O, NaCl—BaCl₂—H₂O, NaCl—CaCl₂—H₂O, LiCl—NaCl—H₂O, LiCl—KCl—H₂O, LiCl—CsCl—H₂O, NaCl—KCl—H₂O, and NaBr—KBr—H₂O. The predictions of the two equations agree well with the experimental data although our new equation is, in general, better.     

一种危险液体混合物的拉曼光谱定性定量识别方法

危险液体混合物的拉曼光谱定性定量分析一直是现场应用难点,为解决该问题,分析了多种物质混合后拉曼光谱的峰位、峰值、峰型变化情况,选取拉曼光谱关键特征峰进行数学简化,构建了从混合物物质成分到混合物拉曼光谱的映射关系,该映射关系描述多种物质成分混合的混合物拉曼特征峰响应只和混合物中各成分本身拉曼特征峰响应以及各物质成分混合比例有关,各物质成分按混合比例贡献拉曼特征谱峰,共同形成最终的混合物拉曼光谱。由该映射关系求逆,可实现从采集到的混合物拉曼光谱计算出各物质成分的混合比例。基于此,设计了危险液体混合物成分定性定量识别方法,主要方法步骤包括,首先进行拉曼光谱数据采集,然后进行拉曼光谱数据处理并获得拉曼特征峰,再进行测试样品与数据谱库标准品的正反向特征峰匹配,如果正反向特征峰匹配系数都比较高,在满足一定阈值条件下,可认定测试样品是某种纯净物,如果不是纯净物,则进入混合物分析,通过拉曼光谱特征峰反向匹配系数筛选,确定混合物成分构成,混合物成分确定后再进行混合物成分比例计算,最终实现危险液体混合物定性定量分析。实验部分,选定丙酮、甲苯、三氯甲烷、乙醇及其混合物进行实验验证,当混合物样品是丙酮、乙醇两种成分按3∶7比例混合时,经拉曼光谱识别方法计算,混合成分计算值是丙酮占比0.245 7,乙醇占比0.706 0;当混合物样品是甲苯、三氯甲烷两种成分按3∶7比例混合时,经拉曼光谱识别方法计算,混合成分计算值是甲苯占比0.323 4,三氯甲烷占比0.763 0;当混合物样品是丙酮、甲苯、乙醇三种成分按4∶3∶3比例混合时,经拉曼光谱识别方法计算,混合成分计算值是丙酮占比0.795 9、甲苯占比0.303 5、乙醇占比0.287 5,实验结果表明,当危险液体混合物成分是两种或三种成分混合时,混合成分计算值基本和实际值吻合,应用危险液体混合物的拉曼光谱定性定量识别方法,可较准确的从拉曼混合光谱中解析出各混合物成分以及各成分在混合物中的比例,可以判断混合物每个拉曼特征谱峰都来自于哪个成分或哪些成分拉曼特征谱峰的混合,谱图解析结果良好,对危险液体混合物现场分析鉴别有较大应用价值。     

Higher-order crack tip fields for functionally graded material plate with transverse shear deformation

The crack tip fields are investigated for a cracked functionally graded material (FGM) plate by Reissner’s linear plate theory with the consideration of the transverse shear deformation generated by bending. The elastic modulus and Poisson’s ratio of the functionally graded plates are assumed to vary continuously through the coordinate y, according to a linear law and a constant, respectively. The governing equations, i.e., the 6th-order partial differential equations with variable coefficients, are derived in the polar coordinate system based on Reissner’s plate theory. Furthermore, the generalized displacements are treated in a separation-of-variable form, and the higher-order crack tip fields of the cracked FGM plate are obtained by the eigen-expansion method. It is found that the analytic solutions degenerate to the corresponding fields of the isotropic homogeneous plate with Reissner’s effect when the in-homogeneity parameter approaches zero.     

李群方法对一阶偏微分方程的应用

本文以李群为工具,给出了一种将一阶非线性偏微分方程化简为一阶拟线性方程或可积的一阶拟线性方程的方法.该方法可用于某些两个自变元的,接受一个或两个李群的一阶非线性偏微分方程,特别可用于某些单自由度Lagrange系统的Hamilton-Jacobi方程的求解.     

羟基氧化铁/膨胀石墨复合材料的制备及除砷机制

以膨胀石墨为载体材料,采用改进后的综合法制备的羟基氧化铁（FeOOH）为改性材料,在酸性及超声波振荡的条件下对膨胀石墨进行表面接枝,制得羟基氧化铁/膨胀石墨复合材料,并对材料进行扫描电子显微镜（SEM）、X射线衍射（XRD）、傅里叶变换红外光谱（FTIR）和X射线光电子能谱（XPS）表征,随后测试了其除砷性能,并探讨了反应机理.实验结果表明,复合材料中羟基氧化铁通过氢键与化学键均匀负载在了膨胀石墨表面,为亚微米级球状;使用0.5 g复合材料处理50 mL浓度为0.5 mg/L的模拟含砷废水,90 min后去除率可达到99%,且经过处理可以使废水中的砷浓度达到饮用标准;载铁量越高,材料的除砷性能越好,当载铁量达到55%时,使用0.5 g复合材料处理50 mL浓度为2.0 mg/L的模拟含砷废水,1 h后去除率达到72.6%,是普通膨胀石墨的3倍;该除砷过程由解离的羟基氧化铁与砷在复合材料附近完成,符合二级动力学方程和Temkin等温吸附模型.     

氧化镍-铁酸锌复合薄膜/锡掺杂玻璃光波导传感元件的制备及其对硫化氢气体的气敏性

用溶胶-凝胶法制成了NiO掺杂的ZnFe2O4溶胶,并用浸渍提拉法将其固定在锡掺杂玻璃光波导表面,研制了NiO-ZnFe2O4复合薄膜/锡掺杂玻璃光波导气敏元件,并对无机有毒气体进行了检测。 实验结果表明,在室温下,该传感元件对H2S气体具有一定的选择性响应,而对相同浓度的其它无机气体的响应相对较小,能够检测到1.0×10-9（体积比）的H2S气体,其响应和恢复时间分别是6和8 s。 该元件具有灵敏度高、响应-恢复快、可逆性和重复性好、容易制备,在室温下便于操作等特点。     

流体静高压原位磁测量的误差研究──（1）漏磁场的影响

 通过五种不同环境分别做原位磁测量和对比，详细研究了13层密绕直螺线管的漏磁通在同步箍紧式高静水压容器内引起的相对误差（Δc₀/c₀）。结果表明：（1）对于空心次级线圈，Δc₀/c₀为-1.90%～-1.27%（400 Hz）或-0.36%～-0.64%（1 000 Hz）。（2）对于钝铁纳米微粉的（Fe-5H）样品，其磁化曲线及起始磁化曲线均为直线，即具有恒磁导率μ。漏磁通过在高压容器内引起的相对误差，Δμ/μ＝3.9%～3.8%，比（2）约大一倍。