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Atroposelective Synthesis of 2-Arylindoles via Chiral Phosphoric Acid-Catalyzed Direct Amination of Indoles

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Chinese Journal of Chemistry 2024年第7期42卷 731-735页

作者： wen Bao Ye-Hui Chen Yu-Wei Liu Shao-hua Xiang Bin Tan School of Pharmacy&StateKey Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhouGansu 730000China Shenzhen Grubbs Institute Department of ChemistrySouthern University of Science and TechnologyShenzhenGuangdong 518055China

Indole-based atropisomers are a very important class of axially chiral ***,the atroposelective synthesis of axially chiral 2-arylindole remains largely *** this study,we report the successful synthesis of atropisomeric 2-arylindoles using direct amination of indoles with p-quinonediimines in the presence of chiral phosphoric acid as a *** acts as an aminating reagent through formal polarity inversion of *** malonate group on the 2-aryl of 2-indoles was found to be essen-tial for high enantioselectivity of the *** could be due to the additional interaction between the ester group and the cata-lyst,as well as the intramolecular hydrogen *** findings provide a new strategy for the asymmetric construction of 2-arylindole atropisomers.

关键词： Chiral phosphoric acid Quinonediimines Direct amination Nucleophilic addition Asymmetric catalysis Enantioselectivity Axially chiral 2-arylindole Atroposelective synthesis

Deformation of Rigid Conjugate Self-dual Galois Representations

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Acta Mathematica Sinica,English Series 2024年第7期40卷 1599-1644页

作者： Yi Feng LIU Yi Chao TIAN Liang xiao Wei ZHANG Xin wen ZHU Institute for Advanced Study in Mathematics Zhejiang UniversityHangzhou 310058P.R.China Morningside Center of Mathematics AMSSChinese Academy of SciencesBeijing 100190P.R.China New Cornerstone Lab Beijing International Center for Mathematical ResearchPeking Ui Beijing 100871P.R.China Department of Mathematics Massachusetts Institute of TechnologyCambridge MA 02139United States Department of Mathematics Stanford UniversityStanfordCA 94305United States

In this article,we study deformations of conjugate self-dual Galois *** study is ***,we prove an R=T type theorem for a conjugate self-dual Galois representation with coefficients in a finite field,satisfying a certain property called ***,we study the rigidity property for the family of residue Galois representations attached to a symmetric power of an elliptic curve,as well as to a regular algebraic conjugate self-dual cuspidal representation.

关键词： Galois deformation rigid conjugate self-dual Galois representations

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Correlation between longitudinal crack occurrence and mold heat transfer in continuous casting based on process data mining

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Journal of Iron and Steel Research International 2024年第5期31卷 1139-1152页

作者： Zhi-qiang Peng Zi-bing Hou Kai Yi Kun-hui Guo Dong-wei Guo Guang-hua wen College of Materials Science and Engineering Chongqing UniversityChongqing400044China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing400044China

The correlation between the longitudinal crack occurrence and integrated heat transfer of the mold with data mining methods was ***,three kinds of support vector machine models based on principal component analysis with different input features were established to explore the effect of integrated heat transfer on the accuracy of the prediction model for the longitudinal *** results show that the accuracy was improved while features including mean and standard deviation of integrated heat transfer were ***,the difference in integrated heat transfer between defect and normal samples under the same process parameters was quantitatively *** with normal samples,the temperature difference of cooling water for defect samples decreased by 0.65%,and the temperature difference fluctuation increased by 31.1%.Finally,the literature data were used to provide support for the quantitative correlation according to defect formation mechanism.A new criterion for the prediction of longitudinal crack and a discovering method for correlation between product quality and process parameters in the manufacturing industry have been provided.

关键词： Continuous casting slab Longitudinal surface crack Heat transfer Data mining Quantitative correlation

Experimental observation of spontaneous symmetry breaking in a quantum phase transition

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 34-39页

作者： wen Ning Ri-hua Zheng Jia-Hao Lu Fan Wu Zhen-Biao Yang Shi-Biao Zheng Fujian Key Laboratory of Quantum Information and Quantum Optics College of Physics and Information EngineeringFuzhou UniversityFuzhou 350108China Hefei National Laboratory Hefei 230088China

Spontaneous symmetry breaking(SSB)plays a central role in understanding a large variety of phenomena associated with phase transitions,such as superfluid and *** far,the transition from a symmetric vacuum to a macroscopically ordered phase has been substantially *** process bridging these two distinct phases is critical to understanding how a classical world emerges from a quantum phase transition,but so far remains unexplored in *** here report an experimental demonstration of such a process with a quantum Rabi model engineered with a superconducting *** move the system from the normal phase to the superradiant phase featuring two symmetry-breaking field components,one of which is observed to emerge as the classical *** results demonstrate that the environment-induced decoherence plays a critical role in the SSB.

关键词： quantum phase transition Rabi model spontaneous symmetry breaking superconducting circuit Schrodinger cat states

Formation of free-surface vortex and vortex suppression by rotating stopper-rod at end of tundish casting

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Journal of Iron and Steel Research International 2024年第5期31卷 1104-1116页

作者： Qing Fang Peng Zhao hua Zhang wen-hao Zhou Gang Yu Jia-hui Wang Hong-wei Ni The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina Hunan Valin Xiangtan Iron and Steel Co. Ltd.Xiangtan411101HunanChina Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan430081HubeiChina

A rotating stopper-rod technique was proposed to suppress the formation of free-surface vortex in the *** large eddy simulation model coupled with volume of fluid model was developed to study the steel–slag–gas three-phase flow *** critical slag entrapment height of the free-surface vortex and mass of residual steel were predicted at different rotating speeds(30,60,90 and 120 r/min)of the rotating *** numerical model was verified by water model *** results showed that by rotating the stopper-rod in the opposite direction of the vortex above the submerged entry nozzle,the formation of vortex can be effectively disturbed and the critical height of the free-surface vortex can be *** for the 2nd strand,when the rotating speeds are 30,60,90 and 120 r/min,the critical height of the free-surface vortex above the 2nd strand is 7.3,4.7,6.3 and 7.4 cm,respectively.A reasonable rotating speed should be 60 r/min,which can reduce about 2 tons of residual *** rotating speeds just can reduce about 1.6 tons of residual steel.

关键词： Tundish Free-surface vortex Stopper-rod Numerical simulation Multiphase flow

Unique method for removal of knotted lumbar epidural catheter: A case report

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World Journal of Clinical Cases 2024年第10期12卷 1824-1829页

作者： Nian-hua Deng xiao-Cong Chen Shou-Bo Quan Anesthesia and Surgery Center Dongguan Songshan Lake Central HospitalDongguan 523326Guangdong ProvinceChina

BACKGROUND Combined spinal-epidural(CSE)anesthesia is the preferred anesthesia method for cesarean *** use of an epidural catheter is essential for administering additional drugs intraoperatively and managing postoperative ***,the insertion of epidural catheters is associated with various complications,such as total spinal anesthesia,symptoms indicative of spinal nerve root irritation,and challenges in epidural catheter *** SUMMARY We present a case report of a challenging epidural catheter removal due to *** lumbar computed tomography scan results revealed that the catheter formed a tight knot in the epidural *** used a novel extubation method and successfully removed the *** The operator can use opposite forces to"spiral"apart the spinal joints by positioning the patient's body in a specific *** findings indicate that,when combined with imaging examination results,this method is effective for the removal of epidural catheters.

关键词： Epidural catheter Knotting Challenging extubation Case report

Current and future research directions in cellular metabolism of colorectal cancer:A bibliometric analysis

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3732-3737页

作者： Bo-wen Jiang Xiu-hua Zhang Rui Ma wen-Yu Luan Yan-Dong Miao Department of Emergency Yantai Affiliated Hospital of Binzhou Medical UniversityThe Second Medical College of Binzhou Medical UniversityYantai 264100Shandong ProvinceChina Department of Oncology Laiyang Central HospitalYantai 265200Shandong ProvinceChina Department of Cancer Center Yantai Affiliated Hospital of Binzhou Medical UniversityThe Second Medical College of Binzhou Medical UniversityYantai 264100Shandong ProvinceChina

The primary aim of this study was to analyze the evolving trends and key focal points in research on cellular metabolism of colorectal cancer(CRC).Relevant publications on cellular metabolism in CRC were sourced from the Science Citation Index Expanded within the Web of Science Core Collection *** analysis and visualization were conducted using VOSviewer(version 1.6.18)software and CiteSpace 6.1.R6(64-bit)Basic.A comprehensive compilation of 4722 English-language publications,covering the period from January 1,1991 to December 31,2022,was carefully identified and included in the *** the authors,“Ogino,Shuji”contributed the most publications in this field,while“Giovannucci,E”garnered the highest number of *** journal“Cancer Research”ranked first in both publication volume and ***,“Shanghai Jiao Tong University”emerged as the top contributor in terms of published articles,while“Harvard University”led in citation *** country-based analysis,the United States held the top position in both publication output and citations,closely followed by *** increasing recognition of the significance of cellular metabolism in CRC underscores its potential for novel therapeutic approaches aimed at improving CRC management and prognosis.

关键词： Cellular metabolism Colorectal cancer Bibliometric analysis Metabolic reprogramming Cellular metabolism

Two-dimensional bifunctional electrocatalyst(Mo-NiFe-LDH)with multilevel structure for highly efficient overall water splitting

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Rare Metals 2024年第6期43卷 2613-2622页

作者： Bao-Jie Zhang Bin Chang Shi-Peng Qiu Gang Zhao xiao Wang Xi-Jin Xu Lan Mu wen-Bo Liao xiao-Jing Dong School of Physics and Technology University of JinanJinan 250000China KAUST Catalysis Center(KCC) King Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Kingdomof SaudiArabia School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China School of Physics and Physical Engineering Qufu Normal UniversityQufu273100China

To effectively address energy challenges,it is crucial to explore efficient and stable bifunctional nonprecious metal *** this study,a Mo-doped nickeliron layered double hydroxide with flower-cluster architecture was successfully prepared by a one-step hydrothermal method,which demonstrated a good water splitting *** an appropriate amount of Mo doping,some lattice distortions in the material provided reactive sites for the adsorption and conversion of intermediates,thus optimising the charge distribution of the ***,the multidimensional void structures formed after doping had a larger specific surface area and accelerated the penetration of the electrolyte,which significantly improved the activity of the catalyst in alkaline *** 10 mA·cm^(-2),the hydrogen and oxygen evolution overpotentials of Mo-doped nickel-iron double hydroxides(Mo-NiFe LDH/NF-0.2)were 167 and 220 mV,respectively,with an excellent durability up to 24 *** the Mo-NiFe LDH/NF-0,2 catalyst was used as the cathode and anode of an electrolytic cell,the catalyst achieved a current density of 10 mA·cm^(-2)at an applied voltage of 1.643 *** study provides a novel approach for designing excellent bifunctional electrocatalysts containing nonprecious metals.

关键词： Bifunctional electrocatalysts 2D multilevel structure Overall water splitting Mo-doped Ni-Fe LDH

SnS_(2) nanosheets decorated SnO_(2) hollow multishelled nanostructures for enhanced sensing of triethylamine gas

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Rare Metals 2024年第5期43卷 2339-2348页

作者： wen-Di Liu Ya Xiong Ao Shen Xin-Zhen Wang xiao Chang wen-Bo Lu Jian Tian School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590China College of Physics Qingdao UniversityQingdao 266071China Zernike Institute for Advanced Materials University of Groningen9747 AG GroningenThe Netherlands

Highly sensitive,fast and low-temperature detection of triethylamine(TEA)gas based on SnO_(2) is attractive yet remains ***,SnS_(2) nanosheets(NSs)/SnO_(2) hollow multishelled structures(HoMSs)-based sensors are designed by the synthesis of SnO_(2) HoMSs,followed by in situ sulfuration with *** varying the thioacetamide levels,Sn S_(2)/SnO_(2) heterostructures with different SnS_(2) contents were obtained and their TEA gas sensing performances were investigated.

关键词： SnS attractive sheets