原油三维荧光分析中猝灭现象辨析

研究了原油的三维荧光猝灭现象，指出浓度过高是原油产生荧光猝灭的主要原因，将会造成三维荧光等值线图畸变，致使定量分析数据失真，谱图特征变异，难以获取原油特征三维指纹图。提出了避免荧光猝灭的预试方法，并列出了不同类型原油的最佳测试浓度。     

Fluorescence decay and quenching of pyrene labeled on sulfonate polyelectrolytes in salt-free aqueous solutions

Fluorescence decay and quenching of pyrene labels on copolymers of 2-acrylamido-2-methylpropanesulphonic acid (AMPS) and N,N-dimethylacrylamide were observed in dilute salt-free aqueous solutions as a function of the mole fraction F_AMPS of AMPS from 0 to 0.896. Monoexponential decay was found for the samples of F_AMPS<0.35 and biexponential decay for the samples of F_AMPS>0.35. The fast decay component is 80%, and the averaged lifetime 〈τ〉 and lifetime τ₁ of the fast decay is decreased with increasing F_AMPS. Quenching efficiency of Cu²⁺, I⁻, CH₃NO₂, and dinitrobenzene to the pyrene label was investigated in the framework of Stern-Volmer plot. With increasing F_AMPS the quenching efficiency of Cu²⁺ is increased while that of I⁻ decreased. For the neutral quenchers, the quenching rate constant k_q increases when F_AMPS<0.449 then decreases, showing a decline of accessibility to the pyrene label. These results were interpreted consistently with the counterion condensation concept, where condensed counterions caused the polyelectrolyte chains to aggregate. The existence of less-polar “temporal aggregated domain” in highly charged polyelectrolytes appears to lead to the slower decay and lower accessibility of the pyrene labels.     

Texaco气化炉激冷室热质传递过程模拟

对Ｔｅｘａｃｏ气化炉激冷室 热质传递过程进行了分析模拟，模拟结果与工业数据吻全良好。通过模拟揭示了现行激冷环损坏的主要原因，探讨了激冷环长周期运行的基本途径，提出了激冷环改进方案。     

A Rapid Freeze‐Quench Setup for Multi‐Frequency EPR Spectroscopy of Enzymatic Reactions

Electron paramagnetic resonance (EPR) spectroscopy in combination with the rapid freeze‐quench (RFQ) technique is a well‐established method to trap and characterize intermediates in chemical or enzymatic reactions at the millisecond or even shorter time scales. The method is particularly powerful for mechanistic studies of enzymatic reactions when combined with high‐frequency EPR (ν≥90 GHz), which permits the identification of substrate or protein radical intermediates by their electronic g values. In this work, we describe a new custom‐designed micro‐mix rapid freeze‐quench apparatus, for which reagent volumes for biological samples as small as 20 μL are required. The apparatus was implemented with homemade sample collectors appropriate for 9, 34, and 94 GHz EPR capillaries (4, 2, and 0.87 mm outer diameter, respectively) and the performance was evaluated. We demonstrate the application potential of the RFQ apparatus by following the enzymatic reaction of PpoA, a fungal dioxygenase producing hydro(pero)xylated fatty acids. The larger spectral resolution at 94 GHz allows the discernment of structural changes in the EPR spectra, which are not detectable in the same samples at the standard 9 GHz frequency.     

轴向分段原料气冷激式氨合成塔的稳态模拟

本文以中、小型合成氨厂内部套管换热式合成塔内件技术改造为背景，试把内件改为轴 向四段原料气冷激式．用ＩＢＭ－ＰＣ计算机进行模拟计算研究．结果表明．利用现有生产厂合成塔耐 高压的外筒，改造其低压内件为冷激式的触媒筐，可以省去触媒层中的换热管和下部换热器，从 而增加触媒的有效装填空间，提高触媒装填率，对各种规模合成塔单塔生产能力都能获得较大幅 度的提高（可达１２０～１６０％）．文中所采用的数学模型、参数和计算程序，经用引进的３０万吨／年 的装置验证，各主要工艺参数的误差小于７％，吻合较好．     

激光光声光谱用于液体样品定量分析的研究

本文报道了光声信号的猝灭现象。在液体样品的激光光声光谱分析中,当待测试样浓度较大时,光声信号强度随浓度增大而减弱。就该现象对液体样品的激光光声光谱测定的影响进行了探讨。     

带奇异项与奇异边界条件的抛物方程的整体解与非整体解

考虑了含奇异项的半线性抛物方程带奇异边界条件的初边值问题，证明了当奇异项取不同的符号时问题存在整体解或在有限时刻发生猝灭．     

Phase separation induced by shear quenching in polymer blends with a diblock copolymer

The effects of adding A–B diblock copolymer to a polymer blend (A/B) on phase‐separation kinetics and morphology have been investigated in a fixed shallow‐quench condition (ΔT = 1.5 °C) by in situ time‐resolved light scattering and phase‐contrast optical microscopy. A shear‐quench technique was used in this study instead of a conventional temperature‐quench method. Mixtures of nearly monodisperse low relative‐molecular masses of polybutadiene (M_w = 2.8 kg/mol), polystyrene (M_w = 2.6 kg/mol), and a near‐symmetric butadiene–styrene diblock copolymer (M_w = 6.3 kg/mol) as an interfacial modifier were studied. We observed that the addition of the diblock copolymer could either retard or accelerate the phase‐separation kinetics depending on the concentration of the diblock copolymer in the homopolymer blends. In contrast to the conventional temperature quench, we observed complex phase‐separation kinetics in the intermediate and late stages of phase separation by the shear‐quench technique. © 2001 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 39: 819–830, 2001     

网带炉织针淬火工艺的研究

分析了工厂网带炉条件下淬火织针表面硬度不足的原因。通过理论研究和现场实验,获得了较佳的加热温度、网带速度、保护气氛等工艺参数,进而提高了织针表面硬度。改进的工艺已被成功地应用于实际生产中。     

大型立式淬火炉温度分布参数系统动态解耦控制算法

针对大型立式淬火炉体积庞大,工况复杂,炉内温度分布呈本征非均匀性,具有多输入/多输出、非线性、强耦合等特性,难以实现炉内温度高精度高均匀性控制目标等问题,提出一种温度分布参数系统动态解耦控制算法,其原理是:采用有限维逼近方法将对象解耦为多个独立的子系统,简化控制器的实现过程;通过分析有限维逼近方法的收敛性,获得保证收敛性的空间和时间步长应满足的条件;解耦后的子系统采用自学习PID控制算法,实现炉内温度高精度和高均匀性控制以及升温过程的快速性和小超调。研究结果表明:温度均匀性由原来的-6～6℃提高到-2～2℃,升温时间由原来的40 min缩短到25 min,超调量由大于15℃减少到小于7℃。