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排序方式: 共有171条查询结果,搜索用时 15 毫秒
71.
ZhiGuoHU ShiLiSONG JianJiWANG LinYANG 《中国化学快报》2004,15(6):707-710
In this paper, the effect of ionic liquids on the CaCO3 crystal growth has been studied for the first time. The obtained CaCO3 crystals were charactcred by the X-ray diffraction and scanning electron micrographs. The results showed that the control ability of ionic liquids for CaCO3 crystals growth was dependent on the counter anion very much. 相似文献
72.
Site-specific Deposition of Colloidal Pd Nanoparticles on Self-assembled Microtubules from Biolipid 总被引:3,自引:0,他引:3
Lipid microtubules with wound ribbon features were fabricated by self-assembling method, and the deposition patterns of colloidal Pd particles on tubular template were investigated. The result indicates that colloidal Pd nanoparticles are preferentially decorated on the helical markings in the interior and on the exterior of preformed tubule and to the edge of loosely helical ribbons to obtain helical deposition features. The multi-bilayer microstructure of tubules can be marked by fine Pd nanoparticles deposited at the edge of helical ribbon. There are the site-specific interactions between lipid tubular template and colloidal Pd particles at the helical edge. A new route was illustrated that colloidal Pd particles firstly attach at the edge of thin flat membranes, and then thin membranes roll up and reassemble into tubule together with particles to form helical deposition patterns. The site-specific deposition of Pd is unbeneficial to obtain the homogeneous metal film on tubules, but it can be utilized to reveal the different chemical nature of lipid molecular assembly. 相似文献
73.
HongXiaLIU ShuShengZHANG JianChenZHANG XiaoYANG LingBoQU YuFenZHAO 《中国化学快报》2005,16(5):643-646
The full scan ESI/MS and ESI/MS^2 of N-(O, O-diisopropyl) phosphoryl aromatic amino acids (DIPPAAAs), N-(O, O-diisopropyl) phosphoryl phenylalanine, N-(O, O-diisopropyl)phosphoryl tryptophan and N-(O, O-diisopropyl) phosphoryl tyrosine, were obtained. The specific ions for them were found. Their stability in the LC mobile phase was investigated using developed HPLC/UV/ESI/MS and the results demonstrated that the DIPPAAAs were stable in the mobile phase (5 mmol/L NH4Ac-MeCN (80:20,v/v, pH7.5) within 48 h. 相似文献
74.
A new transfer matrix method for long-period fiber gratings with coupled multiple cladding modes is proposed and numerically characterized. The transmission spectra of uniform and non-uniform longperiod fiber gratings are numerically characterized. The theoretical results excellently agree with the experimental measurements. Compared with commonly used methods,such as using the fourth-order adaptive step size control of the Runge-Kutta algorithm in solving the coupled mode equation,the new transfer matrix method exhibits a faster calculation speed. 相似文献
75.
Dan Wen Shule Sun Ying Liu Jienan Li Zedeng Yang Aliye Kureshi Yan Fu Henan Li Bowei Jiang Chuan Jin Jifeng Cai Lagabaiyila Zha 《Electrophoresis》2021,42(9-10):1115-1126
The flanking region variants of nonbinary SNPs and phenotype-informative SNPs (piSNPs) have been observed, which may greatly improve the discriminative ability after constituting microhaplotype. In this study, 30 microhaplotype loci based on the nonbinary SNPs and piSNPs (shown to be related to phenotypes such as hair and eye color) were selected. Genotyping were conducted on 100 unrelated northern Han Chinese, and the 26 populations from the 1000 Genome Project were also included for comparison of populations differentiation. The simulated study was conducted for evaluating the efficiency of kinship testing. These 30 microhaplotype loci we selected had good polymorphism, with a mean effective number of alleles (Ae) of 3.46. The average Ae increase was 1.27 compared with the target SNPs. The populations from the five regions worldwide could also be distinguished using these loci. The results of kinship testing showed that these microhaplotype loci had the similar ability as 15 STR loci of AmpFlSTRR IdentifilerR PCR Amplification Kit to identify the biological parent and a stronger ability to exclude the nonbiological parents. So, these 30 microhaplotype loci may be multifunctional for forensic application, including the ability of personal identification and kinship testing equivalent to 15 STR loci, and the power of ancestry inference for distinguishing the main intercontinental population. Moreover, our selected phenotypic microhaplotype loci may theoretically have phenotype prediction capabilities. But the phenotype prediction efficiency of these phenotypic microhaplotype loci may be worse than that of piSNPs and the detailed prediction accuracy of different populations needs to be further studied. 相似文献
76.
XU HongTao WANG XinShou TAO LeiMing & WU SiXin Key Laboratory for Special Functional Materials of Ministry of Education Henan University Kaifeng China 《中国科学:化学》2010,(3)
MCM-41-type mesoporous silica nanospheres(MSN) have been prepared using n-cetyltrimethylammonium bromide(CTAB) as a soft template.The pseudo-moire' rotational pattern inside the MSN results in many interior defects.Hollow mesoporous silica(HMS) spheres were synthesized by solvent extraction of the template from MSN.The morphology and structure of MSN and HMS were studied by TEM,XRD and nitrogen sorption techniques.A model drug,bromocresol green dye,was packed inside different regions of HMS through impregna... 相似文献
77.
Zhang H Zhou Y Li Y Bandosz TJ Akins DL 《Journal of colloid and interface science》2012,375(1):106-111
We have utilized wet-chemical etching of ellipsoidal silica nanoparticles (ESNs) to form silica nanoshells of a range of elliptical morphologies, with the thicknesses of the ellipsoidal silica nanoshells (ESSs) controlled through variation of synthesis conditions. A mechanism has been proposed to explain how the nanoshells are formed, and we demonstrate that the porosity of the silica ellipsoid plays a role in generating silica shells. Our self-templated, wet-etching approach is an attractive alternate procedure to the approaches presently in existence for the following reasons: (i) it is a facile, one-step process that directly produces ellipsoidal silica nanoshells, while overcoming barriers (such as requirement of removing a solid-core template seed) utilized in many reported chemical etching studies; (ii) it results in ellipsoidal silica nanostructures with dimension less than 100 nm; (iii) with an appropriate etchant, the roughness of the silica shells can be well-controlled; and (iv) it results in tunable, uniform size particles with controllable shell thicknesses. Moreover, the silica materials with the unique structures might be adjusted to meet practical application requirements. 相似文献
78.
合成了含Cd和Zn的离子液,使其提供金属离子,与Na2S反应制备离子液包裹的半导体纳米材料.X射线衍射和透射电子显微镜分析结果显示:在Cd离子液与Na2S反应中,得到的是尺寸在5~6nm、离子液包裹CdS纳米晶,而在Zn的体系中,最终产物为尺寸在1μm左右六方盘形貌的ZnO颗粒.用热力学和结晶动力学详细讨论了造成Cd和Zn体系在反应条件相同时,产物的形貌和结构差别的原因.荧光性质的测试结果表明:该方法制备的ZnO和CdS纳米粒子具有很好的荧光性能. 相似文献
79.
Guo Qiang Hu Zhong Quan Zhanga Song Qiang Xiea Wen Long Huangb a Institute of Chemistry & Biology Henan University Kaifeng China b China Pharmaceutical University Nanjing China 《中国化学快报》2010,(6)
<正>Five C3/C3 fluoroquinolone dimers tethered with a fused heterocyclic ring of s-triazolo[2,1-b][1,3,4]thiadiazole derived from antibacterial quinoiones were synthesized and characterized,and their in vitro antitumor activity against L1210,CHO cell lines was evaluated via the respective IC_(50) values. 相似文献
80.