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排序方式: 共有112条查询结果,搜索用时 15 毫秒
1.
齐锋  刘文清  张玉钧  魏庆农  王锋平 《光子学报》2003,32(10):1234-1238
差分吸收光谱技术(DOAS)中采用线性最小二乘拟合方法,用痕量气体标准差分吸收截面对测量得到的差分吸收光谱进行拟合,得出大气中痕量气体的浓度.计算结果的准确性不仅取决于光谱的测量精度,而且受标准差分吸收截面以及仪器函数和温度等诸多因素的影响.详细地分析了计算误差的产生原因,提出了用高浓度样品池得到标准吸收截面的方法,针对光谱固有结构,以及温度对标准吸收截面的影响,改进了浓度反演算法.大量的实验表明,综合运用上述方法,即便对低浓度的样气,相对测量误差也能降低到10%以下.  相似文献   
2.
大孔吸附树脂处理含磺胺废水的研究   总被引:8,自引:0,他引:8  
利用大孔吸附树脂处理含磺胺废水。实验表明,DRHⅢ树脂对磺胺具有良好的吸附-解吸效果。原废水中磺胺浓度约为17.2g/L,COD约为13750mg/L,经树脂吸附处理后,废水中COD去除率约86%,磺胺的吸附率88.2%,树脂的解吸率为97.5%,磺胺的回收率约86.0%,其纯度达99.8%。在废水有效处理的同时实现了废物资源化,具有良好的环境效益和较高的经济效益。  相似文献   
3.
A novel polydopamine-graft-poly(2-methyl-2-oxazoline)(PDA-g-PMOXA) coating was prepared by immobilizing poly(2-methyl-2-oxazoline)(PMOXA) onto material surfaces through polydopamine (PDA) anchored coating for the first time.And then,the chemical composition,hydrophilicity,and protein-resistant properties of the PDA-g-PMOXA coating were studied using X-ray photoelectron spectroscopy(XPS),contact angel(CA) test,surface plasmon resonance(SPR),and quartz crystal microbalance with dissipation(QCM-D) measurement.Finally,the coating was applied to the capillary inner surface for protein separation by capillary electrophoresis(CE).  相似文献   
4.
低分子量的有机胶凝剂组装形成的有机凝胶可应用于药物缓释体系.本研究中,使用亲水的钙黄绿素和疏水的布洛芬为模型分子,研究其在谷氨酸衍生物有机凝胶体系中的缓释行为.研究表明,与药物分子与有机胶凝剂简单混合的体系相比,亲水或疏水的药物分子在有机凝胶体系中的释放速度显著减缓.SEM的研究发现药物粒子嵌入在有机凝胶的三维网络中,因此,有机凝胶的三维网络结构可认为是实现药物缓慢释放的基质,药物分子从网络中的释放受限导致了其从有机凝胶中的缓释行为.  相似文献   
5.
The double perovskite oxides Sr2Mg1-xF exMoO6-δ were investigated as catalysts for the methane oxidation.The structural properties of catalysts were characterized in detail by X-ray diffraction,X-ray photoelectron spectroscopy and X-ray absorption spectroscopy.The catalytic property was strongly influenced by the Fe substitution.The relation between catalytic performance and the degree of Fe substitution was examined with regard to the structure and surface characteristics of the mixed oxides.The Fe-containing catalysts exhibited higher activity attributable to the possible(Fe2+,Mo6+) and (Fe3+,Mo5+)valency pairs,and the highest activity was observed for Sr2Mg0.2Fe0.8MoO6-δ.The enhancement of the catalytic activity may be correlated with the Fe-relating surface lattice oxygen species and was discussed in view of the presence of oxygen vacancies.  相似文献   
6.
环三藜芦烃的分子识别与组装   总被引:1,自引:0,他引:1  
环三藜芦烃是一类基于藜芦醚与甲醛缩聚物的大环主体分子,其具有独特的C3对称结构和刚性的富电子空腔,在超分子化学、材料科学等方面具有潜在的应用价值,受到人们越来越多的重视.本文主要概述了近年来环三藜芦烃及其衍生物在分子识别与超分子组装方面的一些研究进展.  相似文献   
7.
各向异性本构关系在板料成形数值模拟中的应用   总被引:7,自引:0,他引:7  
对几种能表达面内各向异性的屈服准则Hill、Barlat-Lian、Barlat进行了比较。以弹性变形服从各向同性广义虎克定律的情况下,给出了基于张量算法推导的弹塑性本构关系的一般表达式,并由此导出了相应屈服准则的弹塑性本构关系的显式表达。借助ABAQUS软件本构模块用户子程序接口,分别实现了这些屈服准则在ABAQUS的嵌入。以模拟方形盒的拉延过程为例,分析了不同的屈服准则在板料成形过程数值模拟中的应用。模拟结果表明,基于弹塑性本构关系一般表达所列出的相应屈服准则的显式表达式是正确的;在采用壳元来模拟板料成形时,采用Barlat准则的模拟结果和采用Barlat-Lian准则的结果差别不大。  相似文献   
8.
A high detection efficiency calorimeter which is used to detect γ-rays with energies from 1 MeV up to 10 MeV as well as light charged particles has been proposed. Design of the geometry, results of the crystal tests and Monte Carlo simulations are presented in this paper. The simulation results confirm that the calorimeter can obtain high detection efficiency and good energy resolution with the current designed geometry. And the calorimeter is competent for the future External Target Facility (ETF) experiments.  相似文献   
9.
A novel hyperbranched poly(urethane-tetrazole)(HPUTZ) was synthesized via the A2+BB2' approach using hexadiisocyanate(HDI) and 3-(bis-(2-hydroxyethyl)) aminopropyltetrazole(HAPTZ).The molecular structure was characterized by FTIR and 1H NMR spectroscopy.The number average molecular weight was measured to be 1.05×104 g/mol with a polydispersity of 1.27 by GPC analysis.The HPUTZ was further cured by the semi-adduct(PEG-IPDI) from polyethylene glycol(PEG) reacting with isophorone diisocyanate(IPDI) to form th...  相似文献   
10.
许锐  刘超培 《中国物理 C》2010,34(2):224-226
Coherent X-ray microscopy has advanced towards higher-energy, more brilliant sources over the past decade since its demonstrations, and many advancements have been made towards optimizing this imaging technique. Here we present both the experimental instrument for obtaining diffraction patterns and the primary reconstruction of yeast cell 2D projection. In addition, the characteristics of the existing optics at BL29XUL of SPring-8 Facility and the method of image reconstruction are discussed.  相似文献   
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