C2 用于声化学研究的大功率超声系统的研制

根据声化学反应的特殊要求，我们研制了上前用于声化学研究的大功率超声系统，由参数可调节的超声发生器配合不同频率的换能器工作，并用它组合成杯式幅杆结构声化学反应器，解决了有关声化学设备的一些技术问题。为声化学技术从实验室规模向工业应用过渡做了必要的准备。     

多频超声辐照的声化学产额研究进展

声化学是一门新兴的交叉学科，具有很多用途，广泛地应用于医药，生物，海洋，航空，轻工，食品，化学，化工等诸多领域，打基础这年来对声化学的研究十分活跃，多频超声对声化学产额的影响是其中研究的热点之一。声化学反应的主动力是声空化，声化学产额与超声辐照频率有一定的关系。双频，三频正交超声辐照能显著地提高声化学产额，具有明显的增强效应。文章综述了这方面的研究进展情况，阐述了声化学产额的影响因素。提出了目前所存在的问题并进行展望。     

影响声化学产额的几个因素

声空化是声化学反应的主动力，对声化学产额的研究将能更好地利用声化学技术。从大量的实验研究报道结果来看．在既定的物理和化学条件下，声化学产额的高低主要取决于声化学反应器的类型和各类操作参量。文中对影响声化学产额的媒质参量和声学参量作了定性的讨论，这些参量包括媒质的粘滞性、可压缩性、反应器的几何形状、声压和频率等，同时从空化泡群的角度分析了这些参量之间的相互联系，结合目前声化学的研究现状，探讨了今后该领域急需解决的一些问题及发展方向。     

声化学主动力──声空化及其检测技术

本文简要介绍８０年代中期兴起的一个新的化学分枝─—声化学，从能量与物质相互作用的观点对声化学与其他化学分枝做了比较。井指出声化学的广阔应用前景。进而对声空化进行了讨论，强调声空化是声化学反应主动力的观点。最后详细介绍了声空化检测原理与方法的最新研究进展。     

频率对声致羟自由基形成的影响

本文用声化学效率的概念，报道了频率对声致羟自由基形成的影响，在氮气或空气环境中，高频超声辐照所致ＯＨ的化学产率比低频超声辐照时高。     

超声辐照促进声化学产额的研究及应用

针对多频超声促进声化学产额的研究热点问题,简述了单频、双频、三频超声辐照的声化学反映规律及其研究进展,分析了多频辐射能显著提高声化学产额的原因。指出了多频超声在医药方面的应用,尤其是在中药复方提取中更显示出其优越性,可以达到很好的提取率,多频辐射有很好的开发前景。     

声化学技术在强碱催化制备生物柴油中的应用

对声化学技术在强碱催化制备生物柴油方面的研究与应用进行了评述。介绍了催化剂种类及用量、温度、反应时间、醇种类及用量、频率与功率、原料种类等因素对超声场中酯交换反应的影响,同时也对超声促进连续酯交换,水力空化促进酯交换,以及超声辅助萃取酯交换法等声化学新技术进行了分析、评述,指出采用声化学方法具有环境友好、反应快速等优点,但在工程放大、设备设计等方面尚需进一步研究。     

超声雾化对声压谱和声化学反应的影响

超声雾化对声压谱和声化学反应的影响刘金春彭逸华（苏州城建环保学院苏州·２１５０１１）１引言空化动力学［１］表明，只有当气泡自然共振频率高于声波频率，气泡才能经历溃灭过程，形成局部瞬间高温和高压，为声化学反应提供有利的环境条件，这种空化称为有效空化。特...     

用碘释放法研究低频超声的声化学产额

本文用碘释放法研究了２８ｋＨｚ超声的声化学产额随扬强和辐照时间的变化。表明声化学产额随声强呈非线性变化，而随辐照时间近似呈线性变化。进而研究了由２８ｋＨｚ与１．０６ＭＨｚ组成的正交辐照系统的声化学产额。     

超声结合4,4-双甲基姜黄素对DNA损伤的实验研究

文章以4''，6-二脒基-2-苯基吲哚为荧光探针，通过荧光光谱方法研究了超声结合姜黄素类似物4，4-双甲基姜黄素（dimethylcurcumin，DMCU）对DNA的损伤作用，并采用氧化-萃取分光光度法及活性氧清除剂对超声作用过程中活性氧（Reactive Oxygen Species，ROS）的产生及其种类进行了检测和鉴别。结果表明，与单独DMCU作用或单独超声作用相比，超声与DMCU的协同作用对DNA的损伤效应更强，且损伤程度随超声照射时间和DMCU浓度的增加而增大。此外，DMCU在超声作用下会降解，且DMCU的降解速率和程度与一定条件下的DNA损伤程度有关，说明DMCU声化学反应中活性氧的产生是导致DNA损伤的原因。结果表明DMCU有可能成为一种新结构类型的声敏剂。     

Synthesis and kinetics research of ZnS nanoparticles prepared by sonochemical process

Abstract

ZnS nanocrystallites have been successfully prepared by a sonochemical process. The reaction kinetics of the process was also investigated. The as prepared ZnS nanocrystallites were characterised by XRD and TEM. Results show that ZnS nanoparticles can be obtained by sonochemical process using ZnCl₂ and thiacetamide as raw materials. It is found that the as prepared ZnS nanoparticles are hexagonal phase with spherical or spherical-like morphologies. The grain size decreases with increasing ultrasonic irradiation power. Reaction kinetics shows that the weight content of ZnS nanoparticles increases linearly with reaction time at different temperatures. The synthesis activation energy of ZnS nanoparticles is calculated to be 27·80 kJ mol^–1.     

Degradation of polycyclic aromatic hydrocarbons in aqueous solutions by ultrasonic irradiation

The effect of various operating conditions (initial concentration, liquid phase temperature, applied power, ultrasound frequency) and of the presence of matrix components (1-butanol, NaCl and FeSO(4)) on the sonochemical degradation of naphthalene, acenaphthylene and phenanthrene in water has been studied. A horn-type sonicator was used to deliver the ultrasound energy, while immersion sampling solid-phase microextraction (SPME) coupled with GC-MS was employed to follow concentration-time profiles of the chosen PAHs. At the operating conditions in question (initial concentrations of 150, 300 and 450 microg/l, temperatures of 20 and 40 degrees C, applied power of 45, 75 and 150 W and ultrasound frequencies of 24 and 80 kHz), all PAHs were susceptible to sonochemical treatment and, in most cases, complete degradation could be achieved in up to 120 min of treatment. Conversion was found to decrease with increasing initial concentration and temperature and decreasing power and frequency as well as in the presence of an excess of dissolved salts. Addition of 1-butanol, a known hydroxyl radical scavenger, substantially suppressed degradation throughout the course of the reaction, thus highlighting the role of oxidation reactions in PAHs degradation. In contrast, addition of Fe(2+) ions at a low concentration enhanced degradation through a Fenton-like reaction.     

Synthesis of monodisperse Fe3O4 nanoparticles by optimized sonochemical method using mono(ethylene glycol) (MEG)

In this study, we successfully synthesized monodisperse magnetite nanoparticles (NPs) (Fe3O4) by sonochemical method using mono (ethylene glycol) (MEG) as a modifier of the reaction environment and found that MEG could be a good candidate to prevent oxidation and toxicity in sonochemical synthesis. The microstructure and size distribution of the Fe3O4 NPs were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM) respectively. It revealed that the NPs prepared by MEG assisted sonochemical method show a smaller average size and better monodispersity compared to conventional sonochemical method. Due the the reduced average size and uniform size distribution nature of the NPs, it also showed good superparamagnetic properties with very low coercivity less than 0.5 Oe.     

Surface synthesis of PbS nanoparticles on silica spheres by a sonochemical approach

A simple sonochemical approach for the preparation of PbS nanoparticles homogeneously coated on sub-micrometer silica spheres has been described. The transmission electron microscopy and scanning electron microscopy images show that the PbS nanoparticles with size of 30 nm were coated on the silica spheres, without any free nanoparticles. X-ray diffraction reveals that the PbS nanoparticles are of cubic rock-salt structure. Moreover, by dissolving the silica cores with a diluted hydrofluoric acid solution, stable PbS hollow structures were obtained. It is considered that the sonochemical process in which triethanolamine acted as complex agent played an important role for the homogenouse coating of PbS nanoparticles on silica spheres.