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With time-of-flight and electric field ionization detection technique, we investigate the motional Stark effect for highly excited Rydberg barium in high magnetic field and its active cancellation experimentally. In the experiment, the atom beam is aligned at a small angle of 15° with respect to the magnetic field. The motional Stark effect cancellation is demonstrated on two sets of. circularly polarized spectra in static magnetic field B = 1.00000 Tesla and B = 1.70000 Tesla, respectively, although the effect is very small (- 3.5 Vcm^-1) in our apparatus configuration. 相似文献
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掺铝氧化锌ZAO(ZnO:Al)薄膜研究 总被引:2,自引:0,他引:2
描述ZAO(ZnO:Al)薄膜的晶体结构,论述ZAO薄膜的光学、电学性质与其结构的关系,介绍了掺铝氧化锌ZAO薄膜的各种制备方法,并总结了ZAO薄膜在各种领域中的应用.提出了薄膜材料研究的关键问题以及今后的发展方向. 相似文献
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A Supercharged Fluorescent Protein as a Versatile Probe for Homogeneous DNA Detection and Methylation Analysis 下载免费PDF全文
Chunyang Lei Dr. Yan Huang Prof. Dr. Zhou Nie Jun Hu Lijun Li Guoyan Lu Yitao Han Prof. Dr. Shouzhuo Yao 《Angewandte Chemie (International ed. in English)》2014,53(32):8358-8362
Supercharged proteins are a new class of functional proteins with exceptional stability and potent ability to deliver bio‐macromolecules into cells. As a proof‐of‐principle, a novel application of supercharged proteins as a versatile biosensing platform for nucleic acid detection and epigenetics analysis is presented. Taking supercharged green fluorescent protein (ScGFP) as the signal reporter, a simple turn‐on homogenous method for DNA detection has been developed based on the polyionic nanoscale complex of ScGFP/DNA and toehold strand displacement. This assay shows high sensitivity and potent ability to detect single‐base mismatch. Furthermore, combined with bisulfite conversion, this ScGFP‐based assay was further applied to analyze site‐specific DNA methylation status of genomic DNA extracted from real human colon carcinoma tissue sample with ultrahigh sensitivity (4 amol methylated DNA). 相似文献
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Three new metal-organic complexes, namely [Zn(POA)2(H2O)2](1), [Zn(POA)2(H2O)2]·2H2O(2) and [Zn(POA)2]n(3), have been synthesized by organic ligand 2-carboxylic acid-4-nitropyridine-1-oxide(POA) and zinc(Ⅱ) ions. The structures of complexes 1~3 are characterized by single-crystal X-ray analysis, XRD powder diffraction analysis, infrared spectroscopy and thermal stability analysis method. Complex 1 belongs to monoclinic system, space group C2/c with a = 22.8215(15), b = 7.5613(16), c = 10.048(3) ?, β = 109.47°, V = 1634.7(6) ?~3, Z = 4, F(000) = 944, Dc = 1.900 g/cm^3, C(12)H(10)N4O(12)Zn, Mr = 467.61 and μ = 1.584 mm-1. The whole molecule presents "V" shape. Complex 2 is a centrosymmetric structure in triclinic system with space group P1: a = 7.4728(5), b = 7.6825(6), c = 8.5184(6) ?, α = 65.975(2), β = 79.87(2), γ = 89.855(2)°, V = 4384.1(5) ?~3, Z = 1, F(000) = 256, Dc = 1.908 g/cm^3, C(12)H(14)N4O(14)Zn, Mr = 503.64 and μ = 1.492 mm-1. Complex 3 is a one-dimensional chain structure belonging to monoclinic system and space group P21/c with a = 4.9456(6), b = 12.5322(14), c = 11.2514(13) ?, β = 97.313(11)°, V = 6916.8(14) ?~3, Z = 2, F(000) = 432, Dc = 2.072 g/cm^3, C(12)H6N4O(10)Zn, Mr = 431.58, and μ = 1.852 mm-1. In three complexes, six oxygen atoms from the surrounding coordination atoms form a ZnO6 distorted octahedral coordination geometry around the zinc ions. Meanwhile, fluorescent properties of the three complexes were investigated at room temperature. The fluorescence spectroscopic analysis demonstrated that the ligand POA shows red-shift after coordinating with the zinc(Ⅱ) ions. 相似文献
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The system of clustered regularly interspaced short palindromic repeats(CRISPR)and CRISPR-associated endonucleases(Cas)have been widely used in gene editing,disease treatment,molecular diagnosis and chromosome imaging.On account of the programmable target recognition of CRISPR-Cas system and the specific targeting function toward RNA of type Ⅵ class Ⅱ Cas proteins,CRISPR-Cas system has been deployed as RNA recognition and detection tools,exhibiting promising application potentials in the field of RNA detection and imaging.In this review,we summarize the latest research progresses as well as development prospects of CRISPR-Cas system in RNA diagnosis and live cell RNA imaging. 相似文献
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Pan Li Shijun Xu Chunyang Yu Zi‐Ying Li Jianping Xu Zi‐Mu Li Lingyi Zou Xuebing Leng Shan Gao Zhiqiang Liu Xiaoyun Liu Shaodong Zhang 《Angewandte Chemie (International ed. in English)》2020,59(18):7113-7121
Considerable efforts have been made to increase the topological complexity of mechanically interlocked molecules over the years. Three‐dimensional catenated structures composed of two or several (usually symmetrical) cages are one representative example. However, owing to the lack of an efficient universal synthetic strategy, interlocked structures made up of dissymmetric cages are relatively rare. Since the space volume of the inner cavity of an interlocked structure is smaller than that outside it, we developed a novel synthetic approach with the voluminous reductant NaBH(OAc)3 that discriminates this space difference, and therefore selectively reduces the outer surface of a catenated dimer composed of two symmetric cages, thus yielding the corresponding catenane with dissymmetric cages. Insight into the template effect that facilitates the catenation of cages was provided by computational and experimental techniques. 相似文献
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采用生长速率法检测了11科14种高原植物的乙醇提取物对6种植物病原真茵的抑制活性.实验结果显示,在样品的作用浓度为1 mg/mL时,香青、铁线莲、露蕊乌头的乙醇提取物对苹果腐烂病原茵有明显的抑制作用,抑制率分别为77.10%、68.14%、67.53%;香青、露蕊乌头、金露梅、木鳖子对苹果炭疽病原茵也有值得关注的抑制作... 相似文献
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