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91.
采用氯化锌(ZnCl_(2))修饰镉基CdSe/ZnS蓝光量子点(B-QD)薄膜,发现与量子点表面结合力更强的ZnCl_(2)能够部分取代量子点长链配体油酸,有效钝化量子点表面缺陷,提高薄膜的荧光量子效率(PLQY)。此外,由于ZnCl_(2)具有偶极作用,使量子点真空能级提高0.2 eV,一方面可改善电子和空穴载流子注入平衡,另一方面可有效降低发光器件的启亮电压,提高器件的发光寿命。这种无机配体修饰量子点薄膜的方法可能为解决蓝光量子点发光二极管(B-QLEDs)因空穴注入困难和量子点表面缺陷导致器件性能不高的问题提供一个有效思路。 相似文献
92.
以p型硅和苝四甲酸二酐(perylene-3,4,9,10-tetracarboxylic acid dianhydride,PTCDA)为异质结,梳状金(Au)薄膜作为顶电极和光入射窗口制备了光敏二极管。研究表明,PTCDA的厚度和Au电极的厚度对光敏二极管的光响应度有很大的影响。对比不同PTCDA厚度的器件性能,在PTCDA厚度为100 nm时,光响应度最高达到0.3 A/W。进而采用最优化的100 nm厚的PTCDA薄膜制备硅基光敏二极管,对比不同Au电极厚度的器件性能。在Au厚度为20 nm时,器件的光响应度达到最优化的0.5 A/W。 相似文献
93.
Maria das Graças Andrade Korn Elane Santos da Boa Morte Daniele Cristina Muniz Batista dos Santos Jacira Teixeira Castro José Tiago Pereira Barbosa Alete Paixão Teixeira 《应用光谱学评论》2013,48(2):67-92
Abstract The present article gives an overview of recent publications and modern techniques of sample preparation for food analysis employing atomic and inorganic mass spectrometric techniques, such as flame atomic absorption spectrometry, chemical vapor generation atomic absorption and atomic fluorescence spectrometry, graphite furnace atomic absorption spectrometry, inductively coupled plasma optical emission spectrometry, and inductively coupled plasma mass spectrometry. Among the most frequently applied sample preparation techniques for food analysis are dry ashing, usually with the addition of an ashing aid, and acid digestion, preferably with the assistance of microwave energy. Slurry preparation, particularly with the assistance of ultrasound, is increasingly used to reduce acid consumption and sample preparation time. Direct analysis of solid samples is gaining importance in the field of food analysis as it offers the highest sensitivity, avoids the use of acids and other aggressive reagents, makes possible the analysis of micro‐samples, and can be applied for fast screening analysis, e.g., of fresh meat. 相似文献
94.
95.
This study reports the structural and spectroscopic characterization of a novel metal organic compound formulated as [Fe (bpy)3] [Fe (dipic)2]2.7H2O ( 1 ) (dipic = pyridine‐2,6‐dicarboxylate and bpy = 2,2′‐bipyridine). 1 was investigated by elemental analysis, FT‐IR spectroscopy, powder X‐ray diffraction and single crystal X‐ray diffraction (SC‐XRD), which revealed a triclinic structure of expected composition. Thermal degradation of 1 was also investigated. Complex 1 was used as a precursor to prepare superparamagnetic nanoparticles of Fe3O4 by thermal analysis. The obtained Fe3O4 was characterized by Fourier transformed infrared spectroscopy (FT‐IR), powder X‐ray diffraction (XRD) and scanning electron microscopy (SEM). Fe3O4 nanoparticles were used as a nano‐adsorbent to remove Cd2+ from water at room temperature. The results showed that this nano‐adsorbent is effective in removing Cd2+ from contaminated water sources, and that the maximal effectivity of adsorption occurs at pH = 6. Magnetic measurements of complex 1 and Fe3O4 nanoparticles at room temperature revealed paramagnetic and superparamagnetic behavior, respectively. 相似文献
96.
The new inorganic–organic hybrids based on SO3H‐functionalized ionic liquids (ILs) and Keggin‐type heteropoly acids (H3PW12O40, H3PMo12O40, and H4SiW12O40; HPAs) are prepared and characterized by FT‐IR, NMR, XRD, CV, SEM/EDX, ICP‐OES, BJH and UV. Different molecular structures according to the different inorganic part were also proved. Potentiometric titration showed a good relationship between catalytic activity and acidity of the catalysts. Electrochemical aspects showed electron transfer ability of the compounds. For understanding catalytic activities of the HPA‐IL hybrids in N‐formylation reaction, effect of catalyst composition, substrate, and reaction conditions were studied. The best SO3H‐functionalized ionic liquid catalyst was readily recovered and reused for four runs. Easy preparation of the catalyst, simple and easy work‐up, mild reaction conditions, low cost, excellent yields and short reaction times are the key features of this work. 相似文献
97.
We present novel inorganic–organic hybrid catalyst to accomplish domino multi‐component reaction (MCR) for synthesis of 3‐amino‐2′‐oxospiro[benzo[c]pyrano[3,2‐a]phenazine‐1,3′‐indoline]‐2‐carbonitrile/carboxylate derivatives. This methodology offers remarkable development by easy production of H3PMo12O40/Hyd‐SBA‐15 in regard to solving the problem of using harsh catalysts, also it demonstrates to be impressive and environmentally friendly in term of low reaction times and high yields. 相似文献
98.
建立了爆炸残留物中无机阴离子的毛细管离子色谱检测方法.分离柱为Dionex IonPac AS19Capillary柱,通过考察阴离子保留情况,选择以10μL·min-1流速的KOH梯度洗脱,进样量为0.4μL,对爆炸残留物中常见无机阴离子进行了分析.在上述条件下,Cl-,NO2-,ClO3-,NO3-,SO24-,SCN-,ClO4-能很好地分离,并在质量浓度为0.01~5.00μg·mL-1时与对应色谱峰面积之间的线性关系良好,检出限分别为0.36、0.46、1.25、0.92、1.06、1.61、2.65ng·mL-1,回收率为95.84%~102.40%.该方法简便、快速、准确,可用于实际样品的测定. 相似文献
99.
有机-无机自由基盐(DBTTF)6PMo12O40·2H2O的合成、性质和晶体结构 总被引:1,自引:0,他引:1
用电解法制备了有机-无机自由基盐(DBTTF)6PMo12O40·2H2O.用红外光谱、电子光谱和电子自旋共振谱进行了表征,测定了其磁化率、导电性和单晶的晶体结构,该晶体属三斜晶系,P1空间群,晶胞参数为a=1.378 7(7)nm,b=1.420 4(2)nm,c=1.570 2(2)nm,α=104.570(8)°,β=103.41(2)°,γ=95.80(2)°,V=2.853(2)nm3,Z=1,Dc=2.142 Mg·m-3,R=0.072 7. 相似文献
100.
随着互穿聚合物网络(IPN)的发展,出现了无机/有机杂化IPN,调整两组分或多组分互穿程度控制材料的结构、形态与性能,可使材料具有较宽的适用范围.此类材料具有高模量、高韧性,易成型加工. 相似文献