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Chinese Journal of Chemistry 2024年第12期42卷 1399-1406页

作者： Yu Bao Zhi-Jie Song Jin-Long Dai Shenghu Yan Yue Zhang jia-yin wang Guigen Li School of Pharmacy Changzhou UniversityChangzhouJiangsu 213164China Department of Chemistry and Biochemistry Texas Tech University79409USA

Comprehensive Summary A general and convenient photoredox-catalyzed acylation and alkylcyanation of MBH acetates has been established,enabling the assembly of the C(sp2)–C(sp3)bond by a nitrogen-centered radical strategy for the synthesis of trisubstituted alkenes in moderate to excellent chemical yields(48 examples in total).The reaction of MBH acetates with acyl(indanone)oxime esters afforded trisubstituted alkenes containing 1,4-dicarbonyl ***,the use of Eosin Y as a photocatalyst in the catalytic system resulted in the formation of distal cyano group-anchored trisubstituted alkenes via deconstructive functionalization of cycloketone oxime ***,these resulting 1,4-dicarbonyl compounds could be applied to late-stage transformations,providing important methods for the synthesis of dihydropyridazin-3(2H)-one.

关键词： Photocatalysis Radical reactions MBH acetates Oxime esters Stereoselectivity Acylation Alkylation Green chemistry

Aggregation-Induced Catalysis: Asymmetric Catalysis with Chiral Aggregates

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Research 2024年第1期2023卷 525-532页

作者： Yao Tang Yu wang Qingkai Yuan Sai Zhang jia-yin wang Shengzhou Jin Ting Xu Junyi Pan Kazimierz Surowiec Guigen Li Department of Chemistry and Biochemistry Texas Tech UniversityLubbockTX 79409-1061USA School of Chemistry and Chemical Engineering Nanjing UniversityNanjing 210093China School of Pharmacy Continuous Flow Engineering Laboratory of National Petroleum and Chemical IndustryChangzhou UniversityChangzhouJiangsu 213164China

So far,there have been 4 methods to control chirality including the use of chiral auxiliaries,reagents,solvents,and catalysts documented in literature and *** them,asymmetric catalysts are normally divided into homogeneous and heterogeneous *** this report,we present a new type of asymmetric control—asymmetric catalysis via chiral aggregates that would not belong to the above *** new strategy is represented by catalytic asymmetric dihydroxylation reaction of olefins in which chiral ligands are aggregated by taking advantage of typical aggregation-induced emission systems containing tetrahydrofuran and H_(2)O *** was proven that the chiral induction can be enhanced from er of 78:22 to 97:3 simply by changing the ratios of these 2 cosolvents.

关键词： chiral asymmetric Chiral

Experimental Investigation of Bubble Behaviors in Subcooled Flow Boiling

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Journal of Thermal Science 2012年第2期21卷 184-188页

作者： Peng Guan Li jia Liaofei yin Shuo wang Department of Power Engineering School of Mechanical and Electronic Control Engineering Beijing Jiaotong Univer-sity Shangyuancun No.3 100044 Beijing China

The experimental investigation on vapor bubble growth is performed for analyzing subcooled boiling in a vertical annular channel with inner heating surface and upward water flow under atmospheric pressure. Bulk liquid mass flux ranges from 79 kg/m2s to 316 kg/m2s, and subcooling is from 40 K to 60 K. The bubble behaviors from inception to collapse are captured by High-speed photography. The performance of bubble growth recorded by the high-speed photography is given in this paper. The bubble behaviors, effect of the bubble slippage on the heat transfer, and various forces acting on the bubble are discussed.

关键词： subcooled boiling annular channel bubble behaviors visualization

Engaging Yne-Allenes in Cycloaddition Reactions: Recent Developments

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Chinese Journal of Chemistry 2022年第10期40卷 1224-1242页

作者： jia-yin wang Wen-Juan Hao Shu-jiang Tu Bo jiang School of Chemistry&Materials Science Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional MaterialsJiangsu Normal UniversityXuzhouJiangsu 221116China

Yne-allenes bearing both a C-C triple bond and an allene unit are a class of focal substrates in organic synthesis,in view of their structure diversity,.high reactivity and intermediate variety in the past *** yne-allenes in numerous annulation cascades provides efficient and direct accesses to elaborate functionalized polycyclic molecular architectures in a convergent *** are lots of types of catalytic chemical reactions such as intramolecular cyclizations,cycloisomerizations,intermolecular annulations,and bicyclizations as well as tricyclizations with the assistance of Lewis acids,Bronsted acids,bases,transition metals,and otherr c *** review provides an overview of the chemistry developed with transformations of yne-allenes by discussing their general and specific reactivities,presenting and commenting on their mechanisms as well as their applications.

关键词： Yne-alenes Cycloaddition Domino reactions Carbocycles Heterocycles

Reversible Wide-Range Tuneable Luminescence of a Dual-Stimuli- Responsive Silver Cluster-Assembled Material

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Chinese Journal of Chemistry 2019年第11期37卷 1120-1124,I0002页

作者： Xiao-Hong Ma jia-yin wang Jun-Jie Guo Zhao-Yang wang Shuang-Quan Zang College of Chemistry and Molecular Engineering Zhengzhou UniversityZhengzhouHenan 450001China

Background and Originality Content In recent years,the construction of atomically precise noble metal nanoclusters has been extensively studied[1] owing to their favorable photophysical properties and promising applications in photoluminescent materials,optical sensors,catalysis,and biological labelling.[2,3] As a distinct family of noble metal clusters,silver chalcogenolate clusters(SCCs)[4]are a new category of materials with many unusual properties.

关键词： properties. noble silver

Efficient image encryption scheme with synchronous substitution and diffusion based on double S-boxes

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Chinese Physics B 2018年第8期27卷 170-178页

作者： Xuan-Ping Zhang Rui Guo Heng-Wei Chen Zhong-Meng Zhao jia-yin wang School of Electronic and Information Engineering Xi ＇an Jiaotong UniversityXi＇ an 710049China

Single or multiple S-boxes are widely used in image encryption schemes, and in many image encryption schemes the asynchronous encryption structure is utilized, which separates the processes of substitution and diffusion. In this paper, we analyze the defects of this structure based on the example of an article and crack it using a simpler method. To address the defects of the asynchronous encryption structure, a novel encryption scheme is proposed, in which the structure of synchronous substitution and diffusion based on double S-boxes is utilized, so the processes of substitution and diffusion are combined together and the attackers cannot crack the cryptosystem by any of the processes. The simulation results and security analysis show that the proposed encryption scheme is safer and more efficient to expediently use in the real-time system.

关键词： image encryption S-box crack synchronous substitution and diffusion

Aggregation-Induced Synthesis (AIS): Asymmetric Synthesis via Chiral Aggregates

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Research 2022年第4期2022卷 731-739页

作者： Hossein Rouh Yao Tang Ting Xu Qingkai Yuan Sai Zhang jia-yin wang Shengzhou Jin Yu wang Junyi Pan Hannah LWood James D.McDonald Guigen Li Department of Chemistry and Biochemistry Texas Tech UniversityLubbockTexas 79409-1061USA Institute of Chemistry and BioMedical Sciences School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093China

A new chiral aggregate-based tool for asymmetric synthesis has been developed by taking advantage of chiral aggregates of GAP(Group-Assisted Purification)reagents,N-phosphonyl *** tool was proven to be successful in the asymmetric GAP synthesis of functionalized 2,3-dihydrobenzofurans by reacting salicyl N-phosphonyl imines with dialkyl bromomalonates in various cosolvent *** chiral induction can be controlled by differentiating between two asymmetric directions simply by changing the ratios of cosolvents which are commonly adopted in AIE(aggregation-induced emission)*** formation of chiral aggregates was witnessed by a new analytical tool-aggregation-induced polarization(AIP).The present synthetic method will be broadly extended for general organic synthesis,particularly,for asymmetric synthesis and asymmetric catalysis in the future.

关键词： asymmetric chiral synthesis

Orientational Chirality,Its Asymmetric Control,and Computational Study

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Research 2023年第1期2022卷 545-552页

作者： Shengzhou Jin Yu wang Yao Tang jia-yin wang Ting Xu Junyi Pan Sai Zhang Qiankai Yuan Anis Ur Rahman James D.McDonald Guo-Qiang wang Shuhua Li Guigen Li School of Chemistry and Chemical Engineering Nanjing UniversityNanjing210093China Department of Chemistry and Biochemistry Texas Tech UniversityLubbockTX 79409-1061USA Continuous Flow Engineering Laboratory of National Petroleum and Chemical Industry Changzhou UniversityChangzhouJiangsu 213164China

Orientational chirality was discovered and characterized by a C(sp)-C(sp3)axis-anchored chiral center and a remotely anchored blocker.X-ray structural analysis proved that orientatiomers are stabilized by through-space functional groups,making it possible for 1 R-or S-chiral center to exhibit 3 orientational isomers simply by rotating operations.A new model system was proposed,fundamentally different from the traditional Felkin-Ahn-type or Cram-type *** these traditional models,chiral C(sp^(3))center and blocking C(sp^(3))carbons are connected adjacently,and there exist 6 energy barriers during rotating along the C(sp^(2))-C(sp^(3))*** comparison,the present orientational chirality model shows that a chiral C(sp)-C(sp^(3))carbon is remotely located from a blocking ***,it is focused on the steric dialog between a chiral C(sp^(3))center and a remotely anchored functional *** exist 3 energy barriers for either(R)-or(S)-C(sp)-C(sp^(3))stereogenicity in the new *** amide auxiliary was proven to be an excellent chiral auxiliary in controlling rotations of orientatiomers to give complete *** asymmetric synthesis of individual orientatiomers was conducted via multistep synthesis by taking advantage of the Suzuki-Miyaura cross-coupling and Sonogashira coupling *** functional theory computational study presented optimized conformers and relative energies for individual *** discovery would be anticipated to result in a new stereochemistry topic and have a broad impact on chemical,biomedical,and material sciences in the future.

关键词： chiral Chiral rotating

Towards Domain-agnostic Depth Completion

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Machine Intelligence Research 2024年第4期21卷 652-669页

作者： Guangkai Xu Wei yin jianming Zhang Oliver wang Simon Niklaus Simon Chen jia-wang Bian Zhejiang University Hangzhou 310058China Dajiang Technology Shenzhen 518057China Adobe Research California 95110USA University of Oxford Oxford OX12JDUK

Existing depth completion methods are often targeted at a specific sparse depth type and generalize poorly across task *** present a method to complete sparse/semi-dense,noisy,and potentially low-resolution depth maps obtained by various range sensors,including those in modern mobile phones,or by multi-view reconstruction *** method leverages a data-driven prior in the form of a single image depth prediction network trained on large-scale datasets,the output of which is used as an input to our *** propose an effective training scheme where we simulate various sparsity patterns in typical task *** addition,we design two new benchmarks to evaluate the generalizability and robustness of depth completion *** simple method shows superior cross-domain generalization ability against state-of-the-art depth completion methods,introducing a practical solution to highqualitydepthcapture onamobile device.

关键词： Monocular depth estimation depth completion zero-shot generalization scene reconstruction neural network.

Catalytic Enantioselective Construction of 6-4 Ring-Junction All-Carbon Stereocenters and Mechanistic Insights

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Chinese Journal of Chemistry 2022年第15期40卷 1767-1776页

作者： jia-yin wang Chen-Long Li Ting Xu Meng-Fan Li Wen-Juan Hao Shu-jiang Tu jianyi wang Guigen Li Zhi-Xiang Yu Bo jiang School of Chemistry&Materials Science Jiangsu Normal UniversityXuzhouJiangsu 221116China College of Chemistry Peking UniversityBeijing 100871China Medical College Guangxi UniversityNanningGuangxi 530004China Institute of Chemistry&Biomedical Sciences Nanjing UniversityNanjingJiangsu 210093China Department of Chemistry and Biochemistry Texas Tech UniversityLubbockTexas 79409-1061United States

Comprehensive Summary Developing reactions for the synthesis of 6-6-4 and 6-4 carbocyclic scaffolds with a chiral quaternary center at the bridgehead position is highly desired,considering the existence of such skeletons in natural products with biological activities and the potential of using these molecules for downstream studies in chemical biology and medicinal *** here is accessing these target skeletons with high chemo-,regio-and enantio-selectivities through Pd(ll)/chiral N,N'-disulfonyl bisimidazoline(Bim)ligand-catalyzed asymmetric reaction of yne-allenones and arylboronic acids.

关键词： Asymmetric catalysis Palladium Michael addition Chiral cyclobutenes Mechanism