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11.
Dr. Baoyan Xing Dr. Sai Ge Prof. Jianguo Zhao Dr. Hui Yang Dr. Jie Song Dr. Yu Geng Dr. Yuying Qiao Prof. Ling Gu Prof. Peide Han Prof. Guibin Ma 《ChemistryOpen》2020,9(10):1018-1026
Solid-state NMR analysis on wurtzite alloyed CdSe1−xSx crystalline nanoparticles and nanobelts provides evidence that the 113Cd NMR chemical shift is not affected by the varying sizes of nanoparticles, but is sensitive to the S/Se anion molar ratios. A linear correlation is observed between 113Cd NMR chemical shifts and the sulfur component for the alloyed CdSe1−xSx (0<x<1) system both in nanoparticles and nanobelts (δCd=169.71⋅XS+529.21). Based on this correlation, a rapid and applied approach has been developed to determine the composition of the alloyed nanoscalar materials utilizing 113Cd NMR spectroscopy. The observed results from this system confirm that one can use 113Cd NMR spectroscopy not only to determine the composition but also the phase separation of nanomaterial semiconductors without destruction of the sample structures. In addition, some observed correlations are discussed in detail. 相似文献
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液相色谱-双通道原子荧光检测联用法同时测定砷和硒的形态 总被引:6,自引:0,他引:6
建立了一种利用高效液相色谱-双通道原子荧光检测联用同时进行砷和硒形态分析的方法。以10 mmol/L NH4H2PO4溶液(pH 5.6)(添加2.5%(体积分数)的甲醇)为流动相,在12 min内同时分离了三价砷(As(III))、一甲基砷(MMA)、二甲基砷(DMA)、五价砷(As(V))、硒代胱氨酸(SeCys)、硒代蛋氨酸(SeMet)和四价硒[Se(IV)]等化合物。As(III)、DMA、MMA、As(V)、SeCys、SeMet和Se(IV)的检出限分别为1,3,2,3,4,18和3 μg/L (进样量为200 μL),5次测定的相对标准偏差为1.9%~6.1%(As 100 μg/L, Se 300 μg/L)。应用该方法对人体尿样及硒酵母片中砷和硒的形态进行了分析,目标物在尿样中的加标回收率为83%~108%,在硒酵母片中的加标回收率为88%~105%。实验结果表明,该方法可用于尿样及药品中砷和硒形态的日常分析。该方法减少了样品的分析时间和试剂用量,降低了工作强度,提高了工作效率。 相似文献
14.
Dr. Fu Chen Dr. Guibin Ma Dr. Guy M. Bernard Prof. Roderick E. Wasylishen Prof. Ronald G. Cavell Dr. Robert McDonald Dr. Michael J. Ferguson 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(8):2826-2838
Several 1:1 adducts of gallium trihalides with triarylphosphines, X3Ga(PR3) (X=Cl, Br, and I; PR3=triarylphosphine ligand), were investigated by using solid‐state 69/71Ga and 31P NMR spectroscopy at different magnetic‐field strengths. The 69/71Ga nuclear quadrupolar coupling parameters, as well as the gallium and phosphorus magnetic shielding tensors, were determined. The magnitude of the 71Ga quadrupolar coupling constants (CQ(71Ga)) range from approximately 0.9 to 11.0 MHz . The spans of the gallium magnetic shielding tensors for these complexes, δ11?δ33, range from approximately 30 to 380 ppm; those determined for phosphorus range from 10 to 40 ppm. For any given phosphine ligand, the gallium nuclei are most shielded for X=I and least shielded for X=Cl, a trend previously observed for InIII–phosphine complexes. This experimental trend, attributed to spin‐orbit effects of the halogen ligands, is reproduced by DFT calculations. The signs of CQ(69/71Ga) for some of the adducts were determined from the analysis of the 31P NMR spectra acquired with magic angle spinning (MAS). The 1J(69/71Ga,31P) and ΔJ(69/71Ga, 31P) values, as well as their signs, were also determined; values of 1J(71Ga,31P) range from approximately 380 to 1590 Hz. Values of 1J(69/71Ga,31P) and ΔJ(69/71Ga,31P) calculated by using DFT have comparable magnitudes and generally reproduce experimental trends. Both the Fermi‐contact and spin‐dipolar Fermi‐contact mechanisms make important contributions to the 1J(69/71Ga,31P) tensors. The 31P NMR spectra of several adducts in solution, obtained as a function of temperature, are contrasted with those obtained in the solid state. Finally, to complement the analysis of NMR spectra for these adducts, single‐crystal X‐ray diffraction data for Br3Ga[P(p‐Anis)3] and I3Ga[P(p‐Anis)3] were obtained. 相似文献
15.
高效液相色谱与原子荧光光谱联用分析汞化合物形态的研究 总被引:15,自引:2,他引:15
建立了高效液相色谱与原子荧光光谱联用测定汞化合物形态的分析方法。实验对淋洗液组分浓度、氧化剂和还原剂浓度、载气流速及紫外消解管长度等操作条件进行了优化,获得了令人满意的分析结果。在优化的分离检测条件下,20μg/L的汞化合物标准溶液平行7次进样分析,甲基汞、无机汞和乙基汞的色谱峰高的相对标准偏差(RSD)分别为2.0%、2.9%和2.4%;3种汞化合物的线性范围为10~1000μg/L,25μL进样检出限分别为3、2和4μg/L。用建立的方法测定了脉红螺样品中甲基汞的含量,甲基汞和乙基汞的加标回收率分别为90%和92%。 相似文献
16.
本文研究了激光染料Coumarin-480,Oxazine-720,Oxazine-725在聚乙二醇介质中的荧光光谱。结果表明荧光光强度随着聚乙二醇浓度的不断增大而增强,荧光发射的最大峰位有较明显的红移,表明染料分子与聚乙二醇分子间形成了分子缔合物,缔合物愈稳定,荧光强度增强愈大,红移愈大。 相似文献
17.
近红外光谱法同时测定鱼粉中脂肪,蛋白质和水份 总被引:1,自引:0,他引:1
本文使用近红外光谱分析法同时测定鱼粉中的蛋白质,脂肪和水份。本法简便,无污染。 相似文献
18.
Jiao P Zhou H Otto M Mu Q Li L Su G Zhang Y Butch ER Snyder SE Jiang G Yan B 《Journal of the American Chemical Society》2011,133(35):13918-13921
To conquer complex and devastating diseases such as cancer, more coordinated and combined attack strategies are needed. We suggest that these can be beautifully achieved by using nanoconstruct design. We present an example showing that neuroblastoma cells are selectively killed by a nanoconstruct that specifically targets neuroblastoma cells, pushes cells to the vulnerable phase of the cell cycle, and greatly enhances radiation-induced cell death. The success of this multipronged attack approach launched by cell-embedded nanoconstructs demonstrates the power and flexibility of nanotechnology in treating cancer, a difficult task for a small molecule. 相似文献
19.
Facile synthesis of spiny mesoporous titania tubes with enhanced photocatalytic activity 总被引:2,自引:0,他引:2
We demonstrate here for the first time an original and facile approach to synthesizing a novel TiO(2) tube with a spiny mesoporous wall. The photocatalytic activity of the spiny mesoporous tube was greatly enhanced owing to the superior light reflecting ability of the tubular structure as well as the crosslinked spiny nanosheets. 相似文献
20.