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IntroductionTheuseoflarge-PorezeolitessuchasXandYforcarelyzingtheesterificationhasbeenearlysuggestedbyBergklllandnorelationshipbetweentheactivityandsubdueaciditywasobserved.ItalianPatent[2]reportedthatdecationizedYzeolitesareveryactiveandselectivecatalyst… 相似文献
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阐述了计算机动态仿真航天员舱外活动(Extra Vehicular Activity,EVA)的必要性,分析了国外航天员运动仿真的现状,给出了应用计算多刚体系统动力学对航天员舱外活动进行仿真的详细步骤。建立了具体的仿真方法,考虑了反向运动学、反向动力学等,反向动力学采用Kane方法。选取典型的EVA,在对其进行适当简化的基础上,得出了描述该EVA系统运动的7节段6自由度动力学方程,对该EVA进行了仿真计算,并对结果进行了分析。 相似文献
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Wantao Tang Ting Tong Hong Wang Xuehe Lu Changping Yang Yushuai Wu Yuang Wang Prof. Jianbing Liu Prof. Baoquan Ding 《Angewandte Chemie (International ed. in English)》2023,62(51):e202315093
DNA nanostructures have played an important role in the development of novel drug delivery systems. Herein, we report a DNA origami-based CRISPR/Cas9 gene editing system for efficient gene therapy in vivo. In our design, a PAM-rich region precisely organized on the surface of DNA origami can easily recruit and load sgRNA/Cas9 complex by PAM-guided assembly and pre-designed DNA/RNA hybridization. After loading the sgRNA/Cas9 complex, the DNA origami can be further rolled up by the locking strands with a disulfide bond. With the incorporation of DNA aptamer and influenza hemagglutinin (HA) peptide, the cargo-loaded DNA origami can realize the targeted delivery and effective endosomal escape. After reduction by GSH, the opened DNA origami can release the sgRNA/Cas9 complex by RNase H cleavage to achieve a pronounced gene editing of a tumor-associated gene for gene therapy in vivo. This rationally developed DNA origami-based gene editing system presents a new avenue for the development of gene therapy. 相似文献
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流动注射电致化学发光法测定香烟中的绿原酸 总被引:8,自引:0,他引:8
1 引 言绿原酸(CA)是广泛存在于水果、绿茶、烟草、中药等高等植物中的一种多酚衍生物。CA不仅具有抗氧化、缓解紧张、刺激植物生长的功能,还会影响多种酶的活性;CA是原咖啡和烟草中苦味的主要来源,通过改变其含量可以改善咖啡和烟草的品质。因此,建立高灵敏度的CA检测方法对于研究植物生长、确定咖啡和烟草产地、提高其品质具有重要意义。本文研究发现CA能强烈抑制鲁米诺的电致化学发光强度,籍此建立了CA的流动注射电致化学发光抑制检测法,与化学发光方法相比,该法可获得更低的检出限和更宽的线性范围。结… 相似文献
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Yu‐Cheng Chen Jen‐Bin Shi Po‐Feng Wu Chih‐Jung Chen Shui‐Yuang Yang 《Crystal Research and Technology》2012,47(9):991-996
The chalcopyrite CuInS2 thin film was fabricated at 500 °C for 2 h by sulfurization of Cu‐In layers (as precursors) that were sulfurized in a glass tube with pure sulfur powder. The structural, morphological, and optical properties of CuInS2 thin films are characterized using X‐ray diffraction (XRD), field‐emission scanning electron microscope (FE‐SEM), and UV/Visible/NIR spectrophotometer. The study of UV/Visible/NIR absorption shows the band gap energy value of CuInS2 thin films is 1.5 eV. The XRD pattern shows the film is pure CuInS2; no other peaks, such as CuS or CuIn5S8 were observed. Furthermore, the surface of the CuInS2 film is compact characterized by FE‐SEM, which also shows the disappearance of CuS on the surface at 500 °C. 相似文献
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Mingchang Zhu Da Song Ning Liu Kehua Wang Junqi Su Meng Xiong Xi Zhang Yuang Xu Enjun Gao 《应用有机金属化学》2019,33(6)
Two isomeric Zinc (II) complexes constructed by 3,5‐bis(1‐imidazoly) pyridine has been synthesized and characterized by single crystal X‐ray diffraction, elemental analyses and infrared spectroscopy. The binding mode and ability of complex 1–2 with CT‐DNA were studied by UV and fluorescence spectra. The intrinsic binding constant Kb (Kb1 = 2.305 × 104 M?1, Kb2 = 3.095 × 104 M?1) and the observed association constant Kobs (Kobs1 = 1.523*106 M?1, Kobs2 = 2.057*106 M?1) indicated that the insertion ability of complex 2 with CT‐DNA is stronger than complex 1. Gel electrophoresis showed that complexes have a good ability to hydrolyze cleavage pBR322 plasmid DNA. The cytotoxicity and apoptosis studies showed that complexes exhibited excellent cytotoxic activity against HeLa cells, especially complex 2 had better growth inhibition than Cisplatin. Molecular docking study simulated the binding model of complexes with DNA (PDB:4av1), showing an imidazole plane of complex 2 can be inserted into a DNA base pair in relative parallel. Both complexes can be used as potential anticancer agents. 相似文献