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81.
Abstract: In this paper, we consider the transformation of a ray beam as it passes through an optical system containing a
glass plate with parallel surfaces inclined to the optical axis at the Brewster’s angle, by investigating the effects of the
optical system on amplitude and phase distributions. By applying generalized matrix optics and diffraction integrals and considering
the influence of a quarter of a wavelength of aberration on the transmitted amplitude and phase distributions at the focus
of a de-collimating lens, we find that the central peak amplitude descends from 1.0 to 0.8 and the phase distortion is less
than π/2. The general feature of the amplitude distribution shows an elongation along the y-axis perpendicular to the optical
axis in the direction of tilt of the inclined plate, and conforms to the inclination direction of the glass plate.
相似文献
82.
Juan Xu Yan Wang Chao Yang Jianyu Cao Zhidong Chen Chaoying Ni 《Journal of Solid State Electrochemistry》2018,22(12):3853-3862
The supercapacitive performances of supercapacitor mainly depend on the physical nanostructure and micro-morphology of electrode materials. Here, we demonstrated the design, synthesis and electrochemical performances of core-shell hollow carbon nanofiber@nickel-cobalt-layered double hydroxide (HCNF@ Ni0.67Co0.33-LDH) nanocomposites with an optimized Ni/Co molar ratio of 2:1. The HCNF was used as superiorly conductive core to sustain the nanoporous silky Ni0.67Co0.33-LDH shell, which can efficiently provide fast transport pathways for electrons and electrolyte ions. The outstanding specific capacitance of 2486 F g?1 at 1 A g?1 based on galvanostatic charge-discharge curves were acquired for the highly electroactive HCNF@Ni0.67Co0.33-LDH. Furthermore, the HCNF@Ni0.67Co0.33-LDH electrode delivered a distinguished rate capability with a specific capacitance of 1890 F g?1 even at 15 A g?1. Notably, an asymmetric supercapacitor with HCNF@Ni0.67Co0.33-LDH as cathode and HCNF as anode was devised, which presented a prominent specific capacitance of 228 F g?1, good energy density of 62.1 Wh kg?1, and impressive cycling stability (90.6% capacitance retention after 10,000 cycles). 相似文献
83.
Dr. Zeliang Zhuang Dr. Tao Jiang Prof. Dr. Jiaping Lin Dr. Liang Gao Dr. Chaoying Yang Dr. Liquan Wang Dr. Chunhua Cai 《Angewandte Chemie (International ed. in English)》2016,55(40):12522-12527
The self‐organization of pre‐assembled aggregates is an efficient stepwise strategy for fabricating nanostructures with a second level of hierarchy. Herein, we report that anisotropic spindle‐like micelles, self‐assembled from polypeptide graft copolymers with rigid backbones, can serve as ideal pre‐assembled subunits for constructing one‐dimensional materials with hierarchical structures. By adding organic solvents and dialyzing against water, reactive points can be generated at the ends of the spindle‐like micelles, which subsequently drive the anisotropic micelles to grow as rods in a chain and eventually self‐assemble into hierarchical nanowires in a stepwise manner. The second self‐assembly step is a hierarchical process that resembles step polymerization. Hierarchical structures can be precisely synthesized by this new type of polymerization. These nanostructures can be tailored by the activity of the reactive points, which depends on the nature of the solvent and the molecular architecture. 相似文献
84.
Guoqing Wei Lin Kong Jiasui Zhang Chaoying Ma Xiaoqing Wu Xueru Li 《Natural product research》2016,30(23):2704-2706
This study represents the first report on the chemical composition and biological activity of the essential oils from the leaves of Lindera nacusua (D. Don) Merr. Twenty-two compounds were identified and quantified, and the major components of the oil were Caryophyllene oxide (8.79%), Hexahydrofarnesyl acetone (6.83%), β-Selinene (5.02%), Neophytadiene (4.53%), Palmitic acid (4.42%), Phytol (4.36%), α-Copaene (3.89%), 4a,5,8,8a-β-Tetrahydro-2,4,5-trimethyl-1,4-naphthalindione (3.83%), α-Cadinol (3.17%), Bulnesol (2.65%) and 1,4-Dimethyl-7-(1-methylethyl) azulene (2.38%). The in vitro antibacterial activities of the essential oils were evaluated by the disc diffusion method. The inhibition zones against Staphylococcus aureus and Candida albicans were 23.7 and 23 mm. So the essential oil of L. nacusua showed potent antibacterial activity and potential high selectivity against S. aureus and C. albicans. 相似文献
85.
Fang Wang Li Cheng Yuanxin Cao Qisheng Wei Chaoying Tong Shuyun Shi 《Journal of separation science》2022,45(4):938-944
Traditional bioassay-guided investigation of bioactive compounds from natural products comprises critical steps, such as extraction, repeated column separation, and activity assay. Thus, the development of facile, rapid, and efficient technology is critically important. Here, a HepG2 cell-based extraction method was first developed to rapidly screen potential antitumor compounds from the seeds ofCassia obtusifolia. Then, an online extraction and enrichment–high-speed counter-current chromatography (HSCCC) strategy was fabricated to facilely and efficiently isolate target antitumor compounds, which included direct extraction from solid C. obtusifolia, removal of polar interferences, enrichment of target compounds, and preparative isolation by HSCCC using flow rate stepwise increasing mode. After further purification by Sephadex LH-20 column, five antitumor anthraquinones, aurantio-obtusin, 1-desmethylaurantio-obtusin, chryso-obtusin, obtusin, and questin, were obtained for structural characterization and bioassay verification. The results may not only provide new perspectives for facile and rapid investigation of bioactive compounds from complex natural products, but also offer a scientific basis for the potential applications of C. obtusifolia. 相似文献
86.
Jin Liguo Su Chaoying Wang Yuwen Dong Limin 《Journal of inclusion phenomena and macrocyclic chemistry》2022,102(3-4):235-249
Journal of Inclusion Phenomena and Macrocyclic Chemistry - Perovskite solar cells (PSCs) provide attractive prospects for the photovoltaic industry, but the harsh preparation conditions and... 相似文献
87.
Wan C Zhao F Bao X Kandasubramanian B Duggan M 《The journal of physical chemistry. B》2008,112(38):11915-11922
Novel porous aminopropyllsooctyl polyhedral oligomeric silsesquioxane (POSS) modified montmorillonite clay complexes (POSS-Mts) with large interlayer distance and specific surface area have been successfully prepared via ion-exchange reaction and followed by freeze-drying treatment. The morphology of the POSS-Mts is highly influenced by the POSS concentration, pH of the suspension and drying procedure, but the interlayer distance of the POSS-Mts does not change much when the POSS concentration is above 0.4 CEC. The POSS-Mts were used as Sn-catalyst supporters to initiate the ring-opening polymerization of cyclic butylene terephthalate oligomers (CBT) for the first time. No diffraction peak was detected by wide-angle X-ray diffraction for the polymerized composites (pCBT/POSS-Mt), even at 10 wt % loading of POSS-Mt. A clay network rather than exfoliation structure was observed unexpectedly in the composites by transmission electron microscopy. The pCBT/POSS-Mt composite with 10 wt % POSS-Mt was further melt-compounded with commercial PBT resin as a master batch. The tensile properties of the resultant PBT/POSS-Mt composites were highly improved as compared to the pristine PBT due to the homogeneous dispersion of POSS-Mt in the PBT matrix. 相似文献
88.
The numbers of level 2 and level 3 features that can be mapped by CdTe QDs are signifi cantly larger than those obtained by cyanoacrylate fuming (a standard technique being adopted at the forensic crime scene for examination of invisible fi ngerprints) and inkpad imaging. 相似文献
89.
原子吸收光谱法测定水生生物体内铜、锌、镍、铬、铅、镉 总被引:7,自引:0,他引:7
用硝酸-高氯酸体系消解螺蛳和水葫芦样品,采用火焰原子吸收光谱法测定铜、锌、镍、铬,用石墨炉原子吸收光谱法测定铅、镉。铜、锌、镍、铬、铅、镉的检出限分别为0.328、0.126、0.271、0.416、0.006 64、0.001 15 mg/kg,线性相关系数不小于0.999 0,测定结果的相对标准偏差为1.1%~3.7%,加标回收率为86.0%~94.2%。 相似文献
90.