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Cu-Catalyzed Selective Oxy-Cyanoalkylation of Allylamines with Cycloketone Oxime Esters and CO2

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Chinese Journal of Chemistry 2020年第1期38卷 69-76页

作者： Chuan-Kun Ran He Huang Xing-Hui Li Wei Wang Jian-Heng Ye si-shun yan Bi-Qin Wang Chun Feng Da-Gang Yu College of Chemistry and Materials Science Sichuan Normal UniversityChengduSichuan 610068China Key Laboratory of Green Chemistry&Technology of Ministry of Education College of ChemistrySichuan UniversityChengduSichuan 610064China Beijing National Laboratory for Molecular Sciences Beijing 100190China

Summaryof main observation and conclusion The radical-initiated carboxylativecyclization of allylamines with CO2represents an efficientand highly promising strategy to afford valuable ***,the radical precursorsand pathways to generate radicals in such processes are still ***,we report the firstCu-catalyzed selective oxy-cyanoalkylation of allylamines with cycloketone oxime esters and CO2viaC-C bond *** cyanoalkyl-substituted 2-oxazolidinones are obtained in moderate togood yields withhigh regio-and *** utility ofthis re-dox-neutral and cyanide-free method is demonstrated with mild conditions,broad substrate scope,good functional group tolerance and easy scalability.

关键词： amines ketone alkylation

Visible‐light photoredox‐catalyzed carboxylation of benzyl halides with CO_(2):Mild and transition‐metal‐free

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Chinese Journal of Catalysis 2022年第7期43卷 1667-1673页

作者： Ke Jing Ming‐Kai Wei si‐shun yan Li‐Li Liao Ya‐Nan Niu Shu‐Ping Luo Bo Yu Da‐Gang Yu Key Laboratory of Green Chemistry&Technology of Ministry of Education College of ChemistrySichuan UniversityChengdu 610064SichuanChina State Key Laboratory Breeding Base of Green Chemistry‐Synthesis Technology Zhejiang University of TechnologyHangzhou 310014ZhejiangChina

The visible‐light photoredox‐catalyzed carboxylation of benzyl chlorides and bromides with CO_(2) has been *** inexpensive organic dyes as photocatalysts and amines as electron donors,this carboxylation proceeds well in the absence of sensitive organometallic reagents,transition metal catalysts,or metallic reductants.A wide range of commercially available and inexpensive benzyl halides undergo such carboxylation to give valuable aryl acetic acids,including several pharmaceutical molecules and drug precursors,in moderate to high ***,this reaction features mild reaction conditions(one atmospheric pressure of CO_(2) and room temperature),broad substrate scope,good functional group tolerance,easy scalability,and low catalyst loading,thus providing an efficient approach for the assembly of aryl acetic acids.

关键词： Carbon dioxide Visible‐light photoredox catalysis Carboxylation Aryl acetic acids Benzyl halides

Unraveling colorectal cancer prevention:The vitamin D-gut flora-immune system nexus

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2394-2403页

作者： Zhi-Song Zhan Zu-shun Zheng Jing Shi Juan Chen si-Yi Wu Shi-yan Zhang Department of Dentistry Fuding HospitalFujian University of Traditional Chinese MedicineFuding 355200Fujian ProvinceChina Department of Physical Examination Fuding HospitalFujian University of Traditional Chinese MedicineFuding 355200Fujian ProvinceChina Department of Anesthesiology Fuding HospitalFujian University of Traditional Chinese MedicineFuding 355200Fujian ProvinceChina Department of Clinical Laboratory Fuding HospitalFujian University of Traditional Chinese MedicineFuding 355200Fujian ProvinceChina Department of Surgery Fuding HospitalFujian University of Traditional Chinese MedicineFuding 355200Fujian ProvinceChina

Colorectal cancer(CRC)is one of the most common cancers diagnosed in the *** environmental and genetic factors play a major role in the pathogenesis of CRC,extensive research has suggested that vitamin D may play a pivotal role in the development of *** D,primarily obtained through sunlight exposure,dietary sources,and supplements,has long been recognized for its essential functions in maintaining health,including immune *** article delves into the intricate relationship between vitamin D,the immune system,gut flora,and the prevention of *** presents a synthesis of epidemiological data,experimental studies,and clinical trials,highlighting the mechanisms by which vitamin D influences immune cell function,cytokine production,and *** enhancing the immune system’s surveillance and antitumor activity,vitamin D may offer a promising avenue for CRC ***,this comprehensive review delves into the prospective clinical applications of vitamin D supplementation and delineates the forthcoming avenues of research in this dynamic ***,the paper tentatively outlines a spectrum of prophylactic impacts of vitamin D on CRC,emphasizing its significant potential in reducing CRC risk through shedding light on its mechanisms,encompassing antineoplastic mechanisms,influences on the immune system,and modulation of the gut microbiome.

关键词： Colorectal cancer Vitamin D Immune system Gut flora Immunomodulation Microbial dysbiosis Cancer prevention

Global-local combined features to detect pain intensity from facial expression images with attention mechanism

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Journal of Electronic Science and Technology 2024年第3期22卷 80-93页

作者： Jiang Wu Yi Shi shun yan Hong-Mei yan yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou313001China MOE Key Laboratory for Neuroinformation School of Life Science and TechnologyUniversity of Electronic Science and Technology of ChinaChengdu611731China College of Engineering University of California at Santa BarbaraSanta Barbara93106USA

The estimation of pain intensity is critical for medical diagnosis and treatment of *** the development of image monitoring technology and artificial intelligence,automatic pain assessment based on facial expression and behavioral analysis shows a potential value in clinical *** paper reports a framework of convolutional neural network with global and local attention mechanism(GLA-CNN)for the effective detection of pain intensity at four-level thresholds using facial expression ***-CNN includes two modules,namely global attention network(GANet)and local attention network(LANet).LANet is responsible for extracting representative local patch features of faces,while GANet extracts whole facial features to compensate for the ignored correlative features between *** the end,the global correlational and local subtle features are fused for the final estimation of pain *** under the UNBC-McMaster Shoulder Pain database demonstrate that GLA-CNN outperforms other state-of-the-art ***,a visualization analysis is conducted to present the feature map of GLA-CNN,intuitively showing that it can extract not only local pain features but also global correlative facial *** study demonstrates that pain assessment based on facial expression is a non-invasive and feasible method,and can be employed as an auxiliary pain assessment tool in clinical practice.

关键词： Attention Convolutional neural network Facial expression Pain intensity

Visible-light photoredox-catalyzed selective carboxylation of C(sp~2)-F bonds in polyfluoroarenes with CO2

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Chinese Journal of Catalysis 2022年第9期43卷 2388-2394页

作者： Zhi‐Yu Bo si‐shun yan Tian‐Yu Gao Lei Song Chuan‐Kun Ran Yi He Wei Zhang Guang‐Mei Cao Da‐Gang Yu Key Laboratory of Green Chemistry&Technology of Ministry of Education College of ChemistrySichuan UniversityChengdu 610064SichuanChina

Visible light‐driven carboxylation with CO_(2) have emerged as a sustainable and powerful way to transfer waste to ***,it is still challenging for aryl fluorides due to the low reactivities of both C(sp2)−F bonds and CO_(2).Herein,we report the first photocatalytic carboxylation of aryl C−F bonds with CO_(2).The visible‐light photoredox catalysis enables selective carboxylation of strong C(sp2)−F bonds in diverse poly􀏐luoroarenes,such as penta‐,tetra‐,and tri‐fluoroarenes under mild conditions,providing a facile access to a series of important polyfluoroaryl carboxylic acids with good *** contrast to previous reports of direct capture of polyfluoroaryl radicals,mechanistic studies suggest that the reduction of fleeting polyfluoroaryl radicals into polyfluoroaryl anions might be involved in this transformation,which may open a new avenue for photocatalytic functionalization of aryl C−F bonds.

关键词： Carbon dioxide Visible-light photoredox catalysis Carboxylation C-F functionalization Polyfluoroarenes

An analytical model of hot rolling force for a thick plate by combining globally optimal approximation yield criterion and egg-circular velocity field

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Journal of Iron and Steel Research International 2024年第3期31卷 647-659页

作者： shun-hu Zhang Yi Zhang Wen-hao Tian yan Li Shagang School of Iron and Steel Soochow UniversitySuzhou 215021JiangsuChina

For the sake of solving the problem that it is difficult to be integrated for the Mises specific plastic power due to its nonlinearity,a new linear criterion,named the globally optimal approximation criterion,is constructed by the polygonal approximation to the Mises *** new criterion is proved to be the linear function of the principal stress componentsσ1,σ2 andσ3 and the trajectory of it on theπ-plane is a non-equiangular but equilateral dodecagon intersecting the Mises *** theoretical results of the current criterion described by the Lode stress parameters are in excellent accordance with the experimental ***,according to the trend that the metallic flow velocity between rollers aggrandizes gradually from the inlet to the outlet during the hot rolling of a thick plate,a biomimetic velocity field is proposed in which the horizontal velocity component fits the egg-circular curve *** velocity field and its simulated results agree quite ***,using the determined linear criterion,energy analysis of the constructed velocity field is utilized to obtain the interior deformation power,while the vector decomposition approach is utilized to obtain the frictional power and shear *** this basis,the overall power is obtained and the analytical solutions are generated for the rolling torque,rolling force and the coefficient of the stress state under different egg curves by minimizing the neutral ***,the parameter optimization of the characteristic parameterρwhich affects the slope of the egg-circular curve is carried out and the best egg-circular curve which can minimize the energy consumption is *** best agreement between the theoretical and observed values of rolling force and rolling torque is under this curve,and the mean relative errors of the rolling torque and rolling force are no more than 2.93%,while the maximum error is no more than 8.35%.

关键词： Yield criterion Plastic deformation Rolling force Velocity field Analytical solution

A new integrated model of deformation resistance and its application in prediction of rolling force of a thick plate

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Journal of Iron and Steel Research International 2024年第4期31卷 882-893页

作者： shun-hu Zhang yan Li Li-zhi Che Wen-hao Tian Shagang School of Iron and Steel Soochow UniversitySuzhou 215021JiangsuChina

The prediction accuracy of existing models of the rolling force of a thick plate is always very *** address this problem,a high-precision genetic algorithm-backpropagation network(GA-BP)model of deformation resistance was built,and its integration with the traditional fitted model was further ***,a novel rolling force model was obtained by embedding the integration model of deformation resistance in the original model of rolling *** to this research idea,the industrial data are normalized at *** this basis,the interactions among the process parameters were disclosed through the variance analysis,and then described by various virtual *** factors are set as part of input ***,the optimal structure of the GA-BP model of deformation resistance was determined and an integration model of deformation resistance was ***,a novel rolling force model is obtained by substituting the traditional fitted deformation resistance into the sims model with the integration model of the deformation *** results proves that the introduction of virtual factors can increase the hit rate of±5%from 75.8%to 78%and can reduce the root mean square error from 4.72%to 4.48%.Besides,it is found that the mean relative error of the traditional fitted deformation resistance is 0.142,while that of the modified deformation resistance is only *** addition,the mean relative error in the original rolling force model is 0.145,while that of the present model is only 0.03.

关键词： Integration model-Deformation resistance Variance analysis Virtual factor Genetic algorithm-backpropagation network model

Competitive intermetallics formation in Pd-Zn-Cd system via seeded growth from ultra-thin Pd nanosheets for electrocatalytic ethanol oxidation reaction

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Nano Research 2024年第9期17卷 8552-8559页

作者： Donghao Zhang Lianxi si Qianqian Ren Xintong yan Shi Hu Department of Chemistry School of ScienceTianjin Key Laboratory of Molecular Optoelectronic ScienceTianjin UniversityTianjin 300072China

Pd-based catalysts exhibit higher catalytic activity and durability in many electrochemical ***,the electrochemical performance can be further enhanced by fine-tune of the alloy *** binary alloys have been fully studied,the multicomponent alloys are far beyond understanding,which leaves cocktail effect a compromised explanation for the high-entropy *** Pd nanosheet-seeded growth was used to synthesize a Pd-Zn-Cd ternary alloy by accurately controlling the Pd-Zn-Cd molar ratio through adjusting the amount of introduced Cd *** analysis of the crystal phase structure of PdCdZnx and PdZn_(x)Cd_(1-x),the competitive relationship of Zn and Cd in the alloying process with Pd was unveiled:Pd1Cd1 intermetallics(IMC)is thermodynamically favored over Pd_(1)Zn_(1)IMC in the ternary ***,the increased structure stability of PdCd over PdZn does not bring about increased durability in the catalytic ethanol oxidation *** morphology selection of Pd seeds is also crucial for the study,as Pd cubes,Pd tetrahedrons,and Pd octahedrons do not form PdZn in the same *** successful alloying through the seeded growth depends on the maximum diffusion depth of foreign atoms into the seed.

关键词： PdZn alloy seed growth method ethanol oxidation reaction composition control ternary alloying

Superatom-assembled boranes,carboranes,and low-dimensional boron nanomaterials based on aromatic icosahedral B_(12)and C_(2)B_(10)

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Nano Research 2024年第7期17卷 6734-6740页

作者： Qiao-Qiao yan yan-Fang Wei Qiang Chen Yue-Wen Mu si-Dian Li Institute of Molecular Science Shanxi UniversityTaiyuan 030006China

Using the experimentally known aromatic icosahedral superatoms I_(h)B_(12)H_(12)2−and D_(5d)1,12-C_(2)B_(10)H_(12)as building blocks and based on extensive density functional theory calculations,we predict herein a series of core–shell superpolyhedral boranes and carboranes in a bottom-up approach,including the high-symmetry Th B_(12)@B_(152)H_(72)2−(2),C2h C_(2)B_(10)@B_(152)H_(72)(3),D_(3d)B_(12)@B_(144)H_(66)(4),I_(h)B_(12)@C_(24)B_(12)0H_(72)2−(6),and D_(5d)C_(2)B_(10)@C_(24)B_(12)0H_(72)(7).More interestingly,the superatom-assembled linear D2h B_(36)H_(32)^(2−)(8),close-packed planar D_(3d)B_(84)H_(60)^(2−)(10),and nearly close-packed core−shell D_(3d)B_(12)@B144H_(6)6(4)can be extended periodically to form the one-dimensional(1D)α-rhombohedral borane nanowire B_(12)H_(10)(Pmmm)(9),two-dimensional(2D)α-rhombohedral monolayer borophane B_(12)H_(6)(P m1)(11),and the experimentally known three-dimensional(3D)α-rhombohedral boron(R m)(12)which can be viewed as an assembly of the monolayer B_(12)H_(6)(11)staggered in vertical direction,setting up a bottom-up strategy to form low-dimensional boron-based nanomaterials from their borane“seeds”via partial or complete *** bonding analyses indicate that the high stability of these nanostructures originates from the spherical aromaticity of their icosahedral B_(12)or C_(2)B_(10)structural units which possess the universal skeleton electronic configuration of 1S21P61D101F8 following the Wade’s n+1 *** infrared(IR)and Raman spectra of the most-concerned neutral B_(12)@B144H_(6)6(4)and C_(2)B_(10)@C_(24)B_(12)0H_(72)(7)are computationally simulated to facilitate their experimental characterizations.

关键词： superatom-assembling bottom-up approach density functional theory superpolyhedral boranes superpolyhedral carboranes borophanes