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891.
892.
We report the synthesis and the characterization of core-shell Au@Ag nanorods through reduction by the wet chemical method. UV-visible absorption spectra of core-shell Au@Ag nanorods demonstrate the longitudinal mode of localized surface plasmon resonances (LSPRs) can be tailored from 724 to 786 nm by controlling the thickness of the silver shell, as is assessed by transmission electron microscope (TEM). Furthermore, the tunable and well-controlled LSPRs of core-shell Au@Ag nanorods are also investigated by numerical simulation using the finite difference time domain (FDTD) method, which strongly supports the experimental observations. The growth mechanism for core-shell Au@Ag nanorods is proposed, according to experimental observations and numerical calculations.  相似文献   
893.
894.
Cai  Zheng-jie  Liu  Gui-qiang  Liu  Zheng-qi  Liu  Xiao-shan  Pan  Ping-ping  Huang  Shan  Wang  Yan  Liu  Mu-lin  Gao  Huogui 《Plasmonics (Norwell, Mass.)》2016,11(2):683-688

The optical properties of a novel nanostructure consisting of a hexagonal array of aligned vertically three-layered metal-dielectric-metal nanodisks on a silver film are theoretically studied through the finite-difference time-domain method. The novel nanostructure exhibits three obvious optical transmission bands due to the excitation of subradiant plasmon modes, superradiant plasmon modes, and Fano resonances. Surface plasmon polaritons of the underlying Ag film also play a significant role on these three optical transmission bands via coupling with localized surface plasmons of nanodisk pairs. Moreover, the nanostructure also exhibits a good tunability of optical response by modifying the sizes of cylinders, the thickness of underlying metal film, and the dielectric constant of middle layer. These results demonstrate the nanostructure with great advantages in optical sensors and filters.

  相似文献   
895.
Two transgenic rice lines (T2A‐1 and T1C‐19b) expressing cry2A and cry1C genes, respectively, were developed in China, targeting lepidopteran pests including Chilo suppressalis (Walker) (Lepidoptera: Crambidae). The seasonal expression of Cry proteins in different tissues of the rice lines and their resistance to C. suppressalis were assessed in comparison to a Bt rice line expressing a cry1Ab/Ac fusion gene, Huahui 1, which has been granted a biosafety certificate. In general, levels of Cry proteins were T2A‐1 > Huahui 1 > T1C‐19b among rice lines, and leaf > stem > root among rice tissues. The expression patterns of Cry protein in the rice line plants were similar: higher level at early stages than at later stages with an exception that high Cry1C level in T1C‐19b stems at the maturing stage. The bioassay results revealed that the three transgenic rice lines exhibited significantly high resistance against C. suppressalis larvae throughout the rice growing season. According to Cry protein levels in rice tissues, the raw and corrected mortalities of C. suppressalis caused by each Bt rice line were the highest in the seedling and declined through the jointing stage with an exception for T1C‐19b providing an excellent performance at the maturing stage. By comparison, T1C‐19b exhibited more stable and greater resistance to C. suppressalis larvae than T2A‐1, being close to Huahui 1. The results suggest cry1C is an ideal Bt gene for plant transformation for lepidopteran pest control, and T1C‐19b is a promising Bt rice line for commercial use for tolerating lepidopteran rice pests.  相似文献   
896.
选取超声波提取法对红松树皮中多酚类物质的提取工艺进行研究,以多酚提取率作为指标,采用单因素试验及正交试验,研究了物料比、乙醇浓度、提取时间、提取温度对红松多酚提取的影响。结果表明,超声波提取的最佳工艺条件是:物料比(g·m L~(-1))1∶30,乙醇浓度60%,提取时间2.0 h,提取温度80℃。本文也对红松多酚的抗炎作用进行了研究,并与杨树多酚、蓝莓多酚进行了比较,结果表明,在0.01~100μg·m L~(-1)范围内,3种多酚都有一定的抗炎作用,且抗炎作用大小顺序为:蓝莓多酚红松多酚杨树多酚。  相似文献   
897.
目的:了解临床医学专业课程建设情况,总结专科层次临床医学专业教育教学的主要成绩,查找专业建设存在的问题,为专科层次临床医学专业教育教学改革提出改进意见。方法:对我校2013届(应届生)306名、2011届和2012届(往届生)333名专科层次临床医学专业毕业生进行问卷调查,主要调查内容包括:课程内容、课程资源和课程评价。结果:专科层次临床医学专业毕业生认为本专业核心课程知识和技能模块设计合理,且应届毕业生认可度高于往届毕业生;对专业类纸质图书、纸质期刊等课程资源满意度高,认为专业类精品课程、教学视频等课程资源需要进一步改善;毕业生对专业知识考评认可度较高,应届生认可度优于往届生。结论:专科层次临床医学专业课程建设效果较好,特别是课程内容安排和课程评价合理,但在专业技能训练和课程资源建设方面需重点加强。  相似文献   
898.
899.
Simple sequence repeats (SSRs) have been widely used in the construction of linkage maps, quantitative trait loci (QTLs) mapping, and marker-assisted selection (MAS). The availability of the sequenced Actinidia chinensis (kiwifruit) genome allows for the inexpensive and efficient development of microsatellite markers. In this study, a total of 49,067 SSRs were identified and characterized in the genome sequences of kiwifruit. Dinucleotide repeats are the most abundant SSRs, with the AG/TC motif accounting for 44.2 % of all SSRs in the genome. Fifty-five newly derived SSRs, together with 46 previously available SSRs, were integrated into linkage maps of an interspecific kiwifruit population. In addition, eight sex-linked SSR markers (including one previously published SSR) were mapped in the sex-related region on the LG25, suggesting that recombination is partially suppressed to maintain dioecy in kiwifruit. The SSRs developed from this study are a valuable resource for kiwifruit genetics and will contribute to the use of MAS in early sex determination of dioecious plant breeding.  相似文献   
900.
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