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121.
湿化学反应法制备了CaCuxMn3-xMn4 O12(x=0.2,0.4,0.6,0.8,1.0,1.2,1.4)系列材料的前驱体,然后通过高温烧结做成样品,进一步丰富了这类样品的研究内容.X射线衍射表明掺杂Cu2+在x=0.2到x=1.4范围内这些材料都能够成单相.通过Rietveld全谱拟合的方法分析,结果表明随掺...  相似文献   
122.
Wang K  Dai L  Liu Q  Li H  Ju C  Wu J  Li H 《The Analyst》2011,136(20):4344-4349
We report a novel and facile electrodeposition method to fabricate a nano-structure film of the unsubstituted metal phthalocyanine on a glassy carbon electrode (GCE). In this electrodeposition system, unsubstituted iron(II) phthalocyanine (u-FePc) was chosen as the model complex of the unsubstituted metalphthalocyanine, and the ionic liquid 1-octyl-3-methylimidazolium trifluoroacetate was employed as the solvent and electrolyte, thus avoiding the use of additional costly supporting electrolyte. Excellent electrocatalytic performance of the u-FePc nano-structure film was first evaluated by electrocatalytic oxidation of ascorbic acid (AA). Compared with the bare GCE, the oxidation peak potential of AA at u-FePc/GCE shifted negatively about 264 mV, and the oxidation peak current increased about 1.8 times. Furthermore, the as-prepared film was employed for the investigation of luminol electrochemiluminescence (ECL) behavior in neutral solution, which showed excellent performance including under selected experimental conditions, the ECL intensity showing an acceptable linear relationship for luminol concentrations between 5 × 10(-8) and 5 × 10(-6) M, and a linear response to H(2)O(2) over a wide concentration range, from 1.0 × 10(-8) to 1.0 × 10(-5) M in 3.0 μM luminol solution.  相似文献   
123.
Abstract In this article, we extend the definition of uniformly starlike functions and uni- formly convex functions on the unit disk to the unit ball in C^n, give the discriminant criterions for them, and get some inequalities for them.  相似文献   
124.
Henan Wu  Xiaoqing Yue 《代数通讯》2013,41(4):1545-1558
In this article, we study the structure theory of a class of generalized loop Virasoro algebras. In particular, the derivation algebras, the automorphism groups, and the second cohomology groups of generalized loop centerless Virasoro algebras are determined.  相似文献   
125.
应用三维荧光技术,结合化学计量学中的二阶校正算法,在诺氟沙星和左氧氟沙星荧光光谱严重重叠,以及干扰物质存在下对血浆中两种喹诺酮类药物进行了同时定量分析。三维荧光激发波长范围265~510nm,发射波长范围300~650 nm。交替不对称三线性分解(AATLD)算法解析得到的诺氟沙星和左氧氟沙星的平均回收率分别为96.9%和103.9%。方法前处理简单、不需预先分离、可以快速定量分析血浆中光谱相互干扰的待测药物的含量。  相似文献   
126.
Under mild condition,using FeCl3 as catalyst,a series of functionalized diarylmethanes were prepared efficiently from the reactions of arenes with paraformaldehyde.This catalytic system is not sensitive to air and moisture.  相似文献   
127.
A new phenylethanoid glycoside,3-hydroxy-4-methoxy-β-phenylethoxy-O-α-L-rhamnopyranosyl-(1→3)-2-O-acetyl-O-β-D-glucopyranoside, named lophanthoside A,was isolated from Rabdosia lophanthoides(Buch.-Ham.ex D.Don) Hara.Its structure was determined by spectroscopic evidences.  相似文献   
128.
非均匀增益对激光模式的影响   总被引:1,自引:1,他引:0  
张虎  彭玉峰  程祖海 《光子学报》2002,31(6):685-688
利用快速傅里叶变换(FFT)法对有正支共焦非稳腔、流动增益介质的化学氧碘激光器(COIL)与二氧化碳激光器的模场进行了数值模拟,在此基础上分析了介质的非均匀增益对激光模式的影响,为新的腔型设计和光束质量的改善提供了依据..  相似文献   
129.
Hybrid organic-inorganic compounds have attracted increasing interest in recent years due to the possibility of combination of different characteristics of the compounds to get unusual structures, properties, or applications1. Polyoxometalates (POMs) whic…  相似文献   
130.
This paper describes the implementation and functionality of a base-band network for the remote control of scientific instruments, in particular scanning and transmission electron microscopes. The base-band network is a hard-wired connection between keyboard and pointing devices from the remote computers to the CPU of the instrument computer; the video signal is then routed back to the remote user and to a high resolution projection system. The system is independent of software and hardware platform, and is highly reliable.  相似文献   
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