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101.
The enhancement of teleportation fidelity by weak measurement or quantum measurement reversal is investigated. One qubit of a maximally entangled state undergoes the amplitude damping, and the subsequent application of weak measurement or quantum measurement reversal could improve the teleportation fidelity beyond the classical region. The improvement could not be attributed to the increasing of entanglement, quantum discord, classical correlation or total correlation. We declare that it should be owed to the probabilistic nature of the method. 相似文献
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103.
Synthesis and UCST‐type phase behavior of polypeptide with alkyl side‐chains in alcohol or ethanol/water solvent mixtures 下载免费PDF全文
Wenjun Liu Mengxiang Zhu Jiang Xiao Ying Ling Haoyu Tang 《Journal of polymer science. Part A, Polymer chemistry》2016,54(21):3425-3435
A series of thermoresponsive polypeptides bearing 1‐butyl, 1‐hexyl, or 1‐dodecyl side‐chains (i.e., 6a ‐ 6c ) were synthesized by copper‐mediated 1,3‐dipolar cycloaddition with high grafting efficiency (>95%) between side‐chain “clickable” polypeptide, namely poly(γ‐4‐(propargoxycarbonyl)benzyl‐L‐glutamate) ( 5 ) and 1‐azidoalkanes. 5 with different degree of polymerization (DP = 48–86) were prepared from triethylamine initiated ring‐opening polymerization of γ‐4‐(propargoxycarbonyl)benzyl‐L‐glutamic acid based N‐carboxyanhydride ( 4 ). 1H NMR, FTIR, and GPC results revealed the successful preparation of the resulting polypeptides. 6a ‐ 6c showed reversible UCST‐type phase behaviors in methanol, ethanol, and ethanol/water solvent mixtures depending on the polymer main‐chain length, alkyl side‐chain length, weight percentage of ethanol (fw) in the binary solvent, and so forth. FTIR analysis revealed the presence of the van der Waals interaction between the alkyl pendants of polypeptides and alkyl groups of alcoholic solvents. Variable‐temperature UV‐vis spectroscopy revealed that the UCST‐type phase transition temperature (Tpt) increased as polymer main‐chain length or concentration increased. In ethanol/water solvent mixtures, polypeptide with short alkyl pendant (i.e., 1‐butyl group) and short main‐chain length (DP = 41) showed the widest fw range and Tpts in the range of 61.0–71.1 °C. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 3425–3435 相似文献
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106.
One‐Pot Tandem Diastereoselective and Enantioselective Synthesis of Functionalized Oxindole‐Fused Spiropyrazolidine Frameworks 下载免费PDF全文
Liang‐Yong Mei Dr. Xiang‐Ying Tang Prof. Dr. Min Shi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(41):13136-13142
A highly efficient palladium(0)‐catalyzed asymmetric [3+2] cycloaddition using 3‐diazooxindoles serving as dipolarophiles affords functionalized pyrazolidine derivatives in an atom‐economical way. In addition, by trapping the pyrazolidine derivatives with maleimides, the corresponding spiropyrazolidine oxindoles containing multiple stereogenic centers have been obtained in high yields along with moderate to good levels of diastereoselectivity and enantioselectivity under mild conditions. Thus, a novel three‐component one‐pot tandem reaction has been developed. 相似文献
107.
Chai Lan-Qin Zhang Jian-Yu Chen Li-Chuan Li Yao-Xin Tang Li-Jian 《Research on Chemical Intermediates》2016,42(4):3473-3488
Research on Chemical Intermediates - A new mononuclear Zn(II) complex, [Zn(L 2 )2]·CH3OH (HL 2 = 1-(2-{[(E)-3,5-dichloro-2-hydroxybenzylidene]amino}phenyl)ethanone oxime),... 相似文献
108.
A Molecular Platform for Multistate Near‐Infrared Electrochromism and Flip‐Flop,Flip‐Flap‐Flop,and Ternary Memory 下载免费PDF全文
Bin‐Bin Cui Jian‐Hong Tang Jiannian Yao Yu‐Wu Zhong 《Angewandte Chemie (International ed. in English)》2015,54(32):9192-9197
A diruthenium complex with a redox‐active amine bridge has been designed, synthesized, and studied by single‐crystal X‐ray analysis and DFT and TDDFT calculations. It shows three well‐separated redox processes with exclusive near‐infrared (NIR) absorbance at each redox state. The electropolymerized film of a related vinyl‐functionalized complex displays multistate NIR electrochromism with low operational potential, good contrast ratio, and long retention time. Flip‐flop, flip‐flap‐flop, and ternary memories have been realized by using the obtained film (ca. 15–20 nm thick) with three electrochemical inputs and three NIR optical outputs that each displays three levels of signal intensity. 相似文献
109.
Synthesis and Design of Aggregation‐Induced Emission Surfactants: Direct Observation of Micelle Transitions and Microemulsion Droplets 下载免费PDF全文
Dr. Weijiang Guan Dr. Wenjuan Zhou Prof. Dr. Chao Lu Prof. Dr. Ben Zhong Tang 《Angewandte Chemie (International ed. in English)》2015,54(50):15160-15164
The direct visualization of micelle transitions is a long‐standing challenge owing to the intractable aggregation‐caused quenching of light emission in the micelle solution. Herein, we report the synthesis of a surfactant with a tetraphenylethene (TPE) core and aggregation‐induced emission (AIE) characteristics. The transition processes of surfactant micelles and the microemulsion droplets (MEDs) formed by the surfactant with a TPE core were clearly visualized by a high‐contrast fluorescence imaging method. The fluorescence intensity of the MEDs decreased as the size of MEDs increased as a result of weakening of the restriction of intramolecular rotation (RIR). The results of this study deepen our understanding of micelle‐transition processes and provide solid evidence in favor of the hypothesis that the AIE phenomenon has its origin in the RIR of fluorophores in the aggregate state. 相似文献
110.
A Filled‐Honeycomb‐Structured Crystal Formed by Self‐Assembly of a Janus Polyoxometalate–Silsesquioxane (POM–POSS) Co‐Cluster 下载免费PDF全文
Chi Ma Han Wu Zi‐Han Huang Dr. Ruo‐Hai Guo Dr. Min‐Biao Hu Dr. Christian Kübel Prof. Dr. Li‐Tang Yan Prof. Dr. Wei Wang 《Angewandte Chemie (International ed. in English)》2015,54(52):15699-15704
Clusters with diverse structures and functions have been used to create novel cluster‐assembled materials (CAMs). Understanding their self‐assembly process is a prerequisite to optimize their structure and function. Herein, two kinds of unlike organo‐functionalized inorganic clusters are covalently linked by a short organic tether to form a dumbbell‐shaped Janus co‐cluster. In a mixed solvent of acetonitrile and water, it self‐assembles into a crystal with a honeycomb superstructure constructed by hexagonal close‐packed cylinders of the smaller cluster and an orderly arranged framework of the larger cluster. Reconstruction of these structural features via coarse‐grained molecular simulations demonstrates that the cluster crystallization and the nanoscale phase separation between the two incompatible clusters synergistically result in the unique nano‐architecture. Overall, this work opens up new opportunities for generating novel CAMs for advanced future applications. 相似文献