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排序方式: 共有321条查询结果,搜索用时 312 毫秒
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Wai Chung Fu Zheng Wang Dr. Wesley Ting Kwok Chan Prof. Dr. Zhenyang Lin Prof. Dr. Fuk Yee Kwong 《Angewandte Chemie (International ed. in English)》2017,56(25):7166-7170
A versatile π-extension reaction was developed based on the three-component cross-coupling of aryl halides, 2-haloarylcarboxylic acids, and norbornadiene. The transformation is driven by the direction and subsequent decarboxylation of the carboxyl group, while norbornadiene serves as an ortho-C−H activator and ethylene synthon via a retro-Diels–Alder reaction. Comprehensive DFT calculations were performed to account for the catalytic intermediates. 相似文献
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Dr. Ming-Yu Wu Jong-Kai Leung Li Liu Dr. Chuen Kam Dr. Kelvin Yuen Kwong Chan Prof. Dr. Ronald A. Li Prof. Dr. Shun Feng Dr. Sijie Chen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(26):10413-10417
The chromosome periphery (CP) is a complex network that covers the outer surface of chromosomes. It acts as a carrier of nucleolar components, helps maintain chromosome structure, and plays an important role in mitosis. Current methods for fluorescence imaging of CP largely rely on immunostaining. We herein report a small-molecule fluorescent probe, ID-IQ , which possesses aggregation-induced emission (AIE) property, for CP imaging. By labelling the CP, ID-IQ sharply highlighted the chromosome boundaries, which enabled rapid segmentation of touching and overlapping chromosomes, direct identification of the centromere, and clear visualization of chromosome morphology. ID-IQ staining was also compatible with fluorescence in situ hybridization and could assist the precise location of the gene in designated chromosome. Altogether, this study provides a versatile cytogenetic tool for improved chromosome analysis, which greatly benefits the clinical diagnostic testing and genomic research. 相似文献
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A simple and green technique has been developed to prepare hierarchical biomorphic ZrO2-CeO2, using silkworm silk as the template. Different from traditional immersion technics, the whole synthesis process depends more on the restriction or direction functions of the silkwormsilk template. The analytic results showed that ZrO2-CeO2 exhibited a well-crystallized hierarchically interwoven hollow fiber structure with 16-28 μm in diameter. The grain size of the sample calcined at 800 oC was about 14 nm. Consequently, the interwoven meshwork at three dimensions is formed due to the direction of biotemplate. The action mechanism is summarily discussed here. It may bring the biomorphic ZrO2-CeO2 nanomaterials with hierarchical interwoven structures to more applications, such as catalysts. 相似文献
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Acta Mathematicae Applicatae Sinica, English Series - We present some exact integrability cases of the extended Liénard equation y″ + f(y)(y′)n + k(y)(y′)m + g(y)y′ +... 相似文献
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The catalytic cross‐dehydrogenative coupling (CDC) reaction has received intense attention in recent years. The attractive feature of this coupling process is the formation of a C? C bond from two C? H moieties under oxidative conditions. In this Focus Review, recent advances in the palladium‐catalyzed CDC reactions of C(sp2)? H bond are summarized, with a focus on the period from 2011 to early 2013. 相似文献
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In this paper, we use the Ehlich-Zeller-Gärtel inequality to derive an algorithm for finding the global minima of polynomials over hyperrectangles as well as to provide a bounding method for the branch-and-bound algorithm. The latter application of the inequality results in an improved algorithm which gives simultaneously a decreasing upper bound and an increasing lower bound for the global minimum at each iteration. The algorithm can be used also to find the Lipschitz constant of a polynomial. 相似文献
10.
Palladium‐Catalyzed Regioselective Aromatic Extension of Internal Alkynes through a Norbornene‐Controlled Reaction Sequence 下载免费PDF全文
Dr. Qingyang Zhao Dr. Wai Chung Fu Prof. Dr. Fuk Yee Kwong 《Angewandte Chemie (International ed. in English)》2018,57(13):3381-3385
A regioselective aromatic π‐extension reaction of internal alkynes is reported. The proposed method employs three easily available components, namely aryl halides, 2‐haloarylcarboxylic acids, and disubstituted acetylenes. The transformation is driven by a controlled reaction sequence of C?H activation, decarboxylation, and annulation to give poly(hetero)aromatic compounds in a site‐selective fashion. Unlike in previously reported palladium‐catalyzed three‐component annulations, alkyne carbopalladation is the last step of this tandem reaction. 相似文献