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基于碲锌镉探测器的高精度毫米级厚度测量技术研究
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作者 吕亮亮 刘军涛 +6 位作者 李公平 高旭东 宗畅 张正宏 孙淑义 潘小东 李畅 《同位素》 CAS 2023年第3期285-294,共10页
目前厚度测量精度不高或者测量方式复杂,为设计一套操作简单、高效、无损、适用范围广的高精度厚度测量装置,本研究利用^(241)Am放射源和碲锌镉(CZT)探测器,开发一套高精度厚度测量系统,同时提出采用测量条件补偿法实现样品无损、高精... 目前厚度测量精度不高或者测量方式复杂,为设计一套操作简单、高效、无损、适用范围广的高精度厚度测量装置,本研究利用^(241)Am放射源和碲锌镉(CZT)探测器,开发一套高精度厚度测量系统,同时提出采用测量条件补偿法实现样品无损、高精度在线测量。利用Geant4程序对厚度测量系统进行模拟设计,确定准直孔尺寸、源与探测器相对位置和屏蔽层厚度等关键参数。利用搭建的厚度测量系统测量纸张、圆台型样品、陶瓷和高速钢等样品。结果表明,该系统对厚度精度在百微米量级时,可以实现高效、实时在线厚度测量;当对测量精度要求提高时,通过延长测量时间、采用测量条件补偿法等,可实现高精度测量。对于1 mm厚的物质,测量精度可达1μm;该系统长时间工作稳定,24 h内相对标准偏差约为0.057%。 展开更多
关键词 高精度厚度测量 无损测量 碲锌镉探测器 Geant4模拟程序 单能γ吸收法
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A Study of the Characteristics of Microorganisms for Effective Degradation of Marine Oil Spills 被引量:6
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作者 Zhang Zhongzhi Wei Xiaofang +3 位作者 zong chang Yu Hongwen Li Chengjian He Ruibing 《Petroleum Science》 SCIE CAS CSCD 2006年第1期61-67,共7页
Four microorganism strains were isolated from coastal petroleum-polluted soil and sand samples of Bohai Sea oilfield; they were found to degrade marine oil spills effectively. The experimental results show that the de... Four microorganism strains were isolated from coastal petroleum-polluted soil and sand samples of Bohai Sea oilfield; they were found to degrade marine oil spills effectively. The experimental results show that the degradation efficiency of crude oil with these four strains (XT-4, SZ-1-25, B-4-9, BS-3-12) is 95.97%, 96.01%, 97.99% and 98.99%, respectively, in their optimum conditions. The characteristics of bacterial biodegradation are investigated. The simulation biotreatment of oil-contaminated beach sand, with an initial oil content of 5,664mg/kg-dry-sand, shows that the residual oil content is 2,700 mg/kg-dry-sand and 2,679 mg/kg-dry-sand after 170 days' treatment with two bacteria (B-4-9, BS-3- 12), respectively. 展开更多
关键词 Petroleum pollution halophilic bacteria BIODEGRADATION simulation biotreatment of beach sand
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Near-infrared dyes, nanomaterials and proteins 被引量:1
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作者 zong chang Feng Liu +4 位作者 Liang Wang Mengying Deng Chunhua Zhou Qinchao Sun Jun Chu 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第10期1856-1882,共27页
Taking the advantage of reduced scattering and low autofluorescence background, the NIR fluorescence probes, such as fluorescence proteins, organic molecules and nanoparticles, not only hold the promise of in vivo ima... Taking the advantage of reduced scattering and low autofluorescence background, the NIR fluorescence probes, such as fluorescence proteins, organic molecules and nanoparticles, not only hold the promise of in vivo imaging of biological processes in physiology and pathology with high signal-to-noise ratio, but also for clinical diagnosis. In this review, we provide an overview of the recent progress on NIR probes,focusing on fundamental mechanisms of NIR dyes and nanoparticles, and protein engineering strategies for NIR proteins. 展开更多
关键词 NEAR-INFRARED II Small organic DYE Nanoparticles NEAR-INFRARED FLUORESCENT protein BACTERIOPHYTOCHROME Fluorogen
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Mild N-deacylation of secondary amides by alkylation with organocerium reagents 被引量:1
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作者 Ai-E Wang zong chang +1 位作者 Yong-Peng Liu Pei-Qiang Huang 《Chinese Chemical Letters》 SCIE CAS CSCD 2015年第9期1055-1058,共4页
Secondary amides are a class of highly stable compounds serving as versatile starting materials,intermediates and directing groups(amido groups) in organic synthesis.The direct deacylation of secondary amides to rel... Secondary amides are a class of highly stable compounds serving as versatile starting materials,intermediates and directing groups(amido groups) in organic synthesis.The direct deacylation of secondary amides to release amines is an important transformation in organic synthesis.Here,we report a protocol for the deacylation of secondary amides and isolation of amines.The method is based on the activation of amides with Tf_2O.followed by addition of organocerium reagents,and acidic work-up.The reaction proceeded under mild conditions and afforded the corresponding amines,isolated as their hydrochloride salts,in good yields.In combination with the C-H activation functionalization methodology,the method is applicable to the functionalization of aniline as well as conversion of carboxylic derivatives to functionalized ketones. 展开更多
关键词 N-Deacylation Amides Amines Organocerium
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