双低频超声辐射对碘化钾溶液碘释放量影响的研究

用碘释放分析了２４ｋＨｚ,３１ｋＨｚ超声的声化学产率随声强的关系,进而研究了由２４ｋＨｚ与３１ｋＨｚ喇叭型及２４ｋＨｚ喇叭型与３１ｋＨｚ阶梯形变幅轩组成的相向辐射系统的声化学产额．结果表明,双频辐射增强的声化学产额与辐射端面积有关,本文对此现象给出理论解释．     

低频双束超声辐照的频率效应(英文)

两束正交的低兆赫兹的超声辐照可以进一步提高声化学产率,这一现象可望引出一种加速声化学反应的新方法     

基于有机物超声降解的动力学共振模型

为了深化对声化学机理的认识,从声场下空化泡的微观动力学出发,在研究分析现有模型基础上,进一步考虑空化泡的振荡过程及崩溃时界面的传质,提出以共振空化泡为中心的假设,经理论推导建立了新的模型．该模型较深刻表述了实际声化学作用过程,能较准确地反映实际声化学效应和解释各种实验结果．尽管新模型的推导机理与现有模型不同,然而所得到的数学方程与其是等价的,而且从化学动力学深度上拓宽了模型的应用范围,更具普适性．     

声致荧光法及其应用研究

提出了声致荧光法及其光谱检测系统,并由此到出了鲁米诺-氢氧化钠水溶液的声致荧光发射光谱,实现了产化学反应器内超声空化场的声致荧光成像．     

阿莫西林的γ辐照降解过程与机理试验研究

探讨了在60 Co γ-射线辐照下水中阿莫西林的降解过程,考察了阿莫西林初始浓度、吸收剂量对其辐照降解的影响,利用LC-MS分析了阿莫西林的辐解产物,初步揭示了阿莫西林的降解途径.试验结果表明,γ辐照可有效降解水中的阿莫西林,初始浓度较低有利于阿莫西林的降解.阿莫西林的降解率随吸收剂量增大而增大,G值则随吸收剂量增加而降低,阿莫西林去除率随吸收剂量的变化呈指数关系.当阿莫西林的初始浓度为10 mg/L和100 mg/L,辐照剂量为15 kGy时,其降解率分别为100%和95.14%.阿莫西林经过辐照后主要存在6种辐解产物,其准分子离子质量分别为M＋H＋：278、384、382、336、340、294,初步推断其降解过程主要涉及羟基自由基的氧化.     

超声化学在合成纳米材料中的应用

随着纳米科技的飞速发展,合成纳米材料的新方法层出不穷。在这些新方法当中,超声化学方法近年来引起了越来越多的关注。本文中介绍了超声化学法制备纳米材料的原理,并详细介绍了超声化学法在控制合成纳米材料形态方面的应用。     

解吸用声化学反应器的设计与标定

针对溶液中气体解吸的使用特点,自行设计了一套频率、功率、温度、溶液高度等可控的声化学反应器.采用量热法作为检测手段标定声化学反应器超声功率,研究柠檬酸溶液高度、温度和溶液浓度对实际分散在溶液中的超声功率的影响.结果表明,分散在柠檬酸溶液中的超声功率在液位为8 cm时最大;柠檬酸溶液初始温度升高,分散在溶液中的超声功率直线下降;柠檬酸溶液浓度对分散在溶液中的超声功率影响较小.应用所设计的声化学反应器可大大提高柠檬酸盐溶液中二氧化硫的解吸率,5 h时,超声辐射的解吸率要比无超声时高25%.     

双制式温控型声化学反应器研究

在分析传统声化学反应器缺陷的基础上,研制了一种新型声化学反应器.该反应器具有冷却和加热两种温控方式.对反应器的冷却降温性能进行了实验分析.结果表明,该反应器独特设计的冷却降温结构,克服了传统声化学反应器的缺陷,既可有效控制反应介质的温度,又不破坏反应介质中的声场及其超声空化状态.     

A blind modulation recognition algorithm based on cyclic spectral correlation

Cyclic spectral correlation above the bifrequency plane for the received signal was calculated by the strip spectral correlation algorithm （SSCA）and then was normalized. The result was expressed by matrix. The sum of error-square was computed between corresponding elements for the theoretical sampling matrix of all kinds of modulated signals and calculated matrix. The modulation type was recognized by exploiting the minimum value of the sum of error-square. No extracted characteristic parameter and prior information are needed for identifying the modulation type compared to the conventional methods. In addition, the new method extends the recognition scope and has high recognition probability at low SNR. The simulation results obtained by means of Monter-Carlo method proved the presented algorithm.     

Effect of radiation on wettability and floatability of sulfide minerals

The feasibility for modifying the wettability and floatability of sulfide minerals by electron beam irradiation has been studied experimentally. The wettability of crystalline pyrite and floatability of some sulfide as pyrite, arsenopyrite, chalcopyrite and marmatite after irradiation were examined by flotation in a modified Hallimond tube. Experimental results show that the hydrophobicity of crystalline pyrite enhances with the increase of irradiation dose in a low dose range. And the flotation responses of sulfide minerals on irradiation dosevary with the mineral species and particle size. The floatability of minerals can be regulated by altering irradiation dose. An explanationfor the mechanism has been suggested based on the principle of radiation chemistry.     

Development of the CAS-IBB single-particle microbeam for localized irradiation of living cells

A single-particle microbeam facility has been constructed at the Key Laboratory of Ion Beam Bioengineering (LIBB), Chinese Academy of Sciences (CAS). The system was designed to deliver a defined numbers of hydrogen ions, produced by a van de Graaff accelerator, in an energy range of 2.0-3.0 MeV, into an area smaller than that of the nucleus of an individual living cell. The beam is collimated by a borosilicate glass capillary that forms the beam-line exit. An integrated computer program recognizes the cells and locates them one by one over the microbeam exit for irradiation. We present technical details of the CAS-LIBB microbeam facility, particularly on the collimator, hardware, control program, as well as cell irradiation protocols available. Various factors contributing to the targeting and positioning precision are discussed along with accuracy measurement results.     

四棱台容器对声化学产率的影响

依据四棱台和四棱柱形状的差异,研究了声化学产率.结果表明,斜四棱台的效果最佳,大约是倒四棱台的3 倍;倒四棱台(斗形状)的效果最差.这表明声化学产率与容器形状有关.     

经激光辐照的40Cr钢的疲劳性能

在本试验研究中,选原始状态完全相同的 40Cr 钢两种圆棒形试样,一种是未经激光辐照,另一种经激光大面积辐照强化处理,同时进行疲劳试验,以考查其疲劳性能的变化,通过金相观察,断口形貌分析和疲劳试验数据的处理分析,证明40Cr钢圆棒形试样用激光辐照强化处理以提高其疲劳性能是有效的和实际可能的,使40Cr钢疲劳极限提高了55％,使疲劳寿命明显地提高,最高可达56.2倍。     

Fullerenes C60 and C70 in flames

The fullerenes C60 and C70 were first identified in carbon vapour produced by laser irradiation of graphite, and have recently been produced in macroscopic quantities by vaporization of graphite with resistive heating. It has also been suggested that fullerenes might be formed in sooting flames, and indeed all-carbon ions with mass/charge ratios suggestive of fullerenes have been detected in flames. These species were assumed to have the cage structures of fullerenes, but the mass spectroscopic evidence could not establish this conclusively. We have now collected samples of condensible compounds and soot from hydrocarbon combustion under a range of conditions, and analysed these using conventional techniques in an effort to detect fullerenes. Spectroscopic studies reveal the presence of C60 and C70 in yields and ratios that depend on temperature, pressure, carbon/oxygen ratio and residence time in the flame. Control of these conditions allows optimal yields of 3 g of fullerenes per kilogram of fuel carbon burned, and variation of the C70/C60 ratio over the range 0.26-5.7.     

Photochemistry of hypocrellin derivatives under anaerobic conditions

To improve the red absorption and solubility of hypocrellin, we have synthesized a series of hypocrellin B derivatives. The photochemistry of these new compounds in anaerobic media has been investigated by using electronic paramagnetic resonance (EPR) and spectrophotometric methods. The semiquinone anion radicals can be produced by self-electron transfer on irradiation, with the formation efficiency and EPR hyperfine structures of the semiquinone anion radicals dependent on the structures of the derivatives. When an electron donor is present, the electron transfer from electron donor to hypocrellin B derivatives enhanced the production of the corresponding semiquinone anion radical; in addition, the semiquinone anion radical and hydroquinone can be detected spectrophotometrically. Structural modifications exert little effect on the absorption position of semiquinone anion radical and hydroquinone, but influence their formation efficiency significantly.     

太阳辐射变化对光伏电站最佳倾角的影响分析

从中国典型资源区选取6个一级辐射站(北京、额济纳旗、格尔木、拉萨、喀什、郑州站)1961—2016年的太阳总辐射、水平面直接辐射和散射辐射数据资料,在用气候倾向估计法分析太阳辐射的变化趋势和利用Klein-Hay模型计算分析最佳倾角的基础上,分析太阳辐射变化对光伏电站最佳倾角的影响.结果显示:(1)近56年,6个一级辐射站的太阳辐射量的总体变化趋势是下降的;除格尔木市和郑州市外,其他4个城市的水平面直接辐射量呈下降趋势;从2003年开始,北京市出现散射比大于直射比的情况;1976年后,郑州市的散射比大于直射比;格尔木、喀什、拉萨市近56年的直射比均高于散射比;额济纳旗市的直射比、散射比变化不明显. (2) 6个典型资源区一级辐射站的最佳倾角随着太阳辐射量的降低而减小;北京、喀什、拉萨市的最佳倾角的下降受总辐射量和直射比的影响;格尔木市和郑州市的最佳倾角的下降受总辐射量和散射比的影响.     

超声化学的基本原理及其在化学合成和环境保护方面的应用

超声波技术作为一种物理手段和工具，能够在化学反应常用的介质中产生一系列接近于极端的条件，这种能量不仅能够激发或促进许多化学反应、加快化学反应速度，甚至还可以改变某些化学反应的方向，产生一些令人意想不到的效果和奇迹。目前对超声化学的研究已涉及到化学、材料学、环保等许多领域。本文介绍了超声化学的基本原理及其在有机合成、治理难生物降解有毒有机污染物方面的应用。     

基于频谱分析方法的超声空化场三维重建及其分布

超声空化是声化学反应的主动力,采用水听器对超声清洗槽内的超声空化场进行定量测量,通过频谱分析对声场能量进行分离,并利用非线性能量来表征空化能量,再通过MATLAB软件对测量结果进行三维重建,该方法同时具备了定量性和直观性两种优势.同时,通过图形用户界面(GUI)对程序进行封装,增强了该方法的可操作性.基于此方法,进一步研究了液体中超声空化场的三维分布情况,并对其分布规律进行了探讨,从而为声化学反应提供了理论指导.     

声化学应用研究进展综述

本文简述了声化学的基本原理，综述了声化学在化学领域中的应用以及与之有关的声化学反应器的研究进展情况，为研究声化学的科研人员提供有益的参考．关键词##4声化学;;应用;;声化学反应器     

萘亚胺类化合物对DNA光敏剪切作用的初步研究

研究了Ｎ－（Ｎ,Ｎ－二甲基）－乙胺－１,８－萘硫酰亚胺和Ｎ－（Ｎ,Ｎ－二甲基）－乙胺－１,８－萘酰亚胺对小牛胸腺ＤＮＡ的嵌入结合反应,并求取了嵌入常数,它们可以把质粒ｐＵＣ１９的超螺旋ＤＮＡ剪切为开环ＤＮＡ,在紫外光作用下,这种能力会得到不同程度的提高。