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Ni-Catalyzed Enantioselective Difunctionalization of Alkynes to Azepine Derivatives Bearing a Quaternary Center and an Unprotected Imine

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Chinese Journal of Chemistry 2024年第8期42卷 873-878页

作者： Jian Long Zhiwu Lu xiao-Lin Li Peng Xue wen-Bo Liu Engineering Research Center of Organosilicon Compounds&Materials(Ministry of Education)and College of Chemistry and Molecular Sciences Wuhan UniversityWuhanHubei430072 China

Comprehensive Summary,The azepine ring is a prominent structural scaffold in biologically significant molecules. In this study, we present a Ni(II)-catalyzed asymmetric difunctionalization of alkynes, involving intermolecular regioselective arylation and intramolecular nitrile addition, enabling the synthesis of enantioenriched azepine derivatives. This reaction simultaneously installs an all-carbon quaternary stereocenter and introduces an unprotected imine functionality, showing great promise for subsequent transformations. The reaction exhibits good tolerance toward various functional groups, resulting in high yields and enantioselectivities. The synthetic utility of this methodology is further demonstrated through gram-scale synthesis and product derivatization. This research offers an efficient approach to the synthesis of seven-membered nitrogen heterocycles.

关键词： Nickel Asymmetric catalysis N-Heterocycles Alkyne functionalization Quaternary centers

A Comparative Study on the Post-Buckling Behavior of Reinforced Thermoplastic Pipes(RTPs)Under External Pressure Considering Progressive Failure

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China Ocean Engineering 2024年第2期38卷 233-246页

作者： DING Xin-dong WANG Shu-qing LIU wen-cheng YE xiao-han College of Engineering Ocean University of ChinaQingdao 266100China Shandong Provincial Key Laboratory of Ocean Engineering Ocean University of ChinaQingdao 266100China Department of Marine Technology Norwegian University of Science and Technology(NTNU)Trondheim NO-7491Norway

The collapse pressure is a key parameter when RTPs are applied in harsh deep-water *** investigate the collapse of RTPs,numerical simulations and hydrostatic pressure tests are *** the numerical simulations,the eigenvalue analysis and Riks analysis are combined,in which the Hashin failure criterion and fracture energy stiffness degradation model are used to simulate the progressive failure of composites,and the“infinite”boundary conditions are applied to eliminate the boundary *** for the hydrostatic pressure tests,RTP specimens were placed in a hydrostatic chamber after filled with *** has been observed that the cross-section of the middle part collapses when it reaches the maximum *** collapse pressure obtained from the numerical simulations agrees well with that in the ***,the applicability of NASA SP-8007 formula on the collapse pressure prediction was also *** has a relatively greater difference because of the ignorance of the progressive failure of *** the parametric study,it is found that RTPs have much higher first-ply-failure pressure when the winding angles are between 50°and 70°.Besides,the effect of debonding and initial ovality,and the contribution of the liner and coating are also discussed.

关键词： reinforced thermoplastic pipes post-buckling behavior progressive failure of composites debonding initial ovality

Upadacitinib for refractory ulcerative colitis with primary nonresponse to infliximab and vedolizumab:A case report

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World Journal of Clinical Cases 2024年第9期12卷 1685-1690页

作者： Xuan Xu Jing-wen Jiang bing-Yun Lu Xia-Xi Li Department of Gastroenterology Shenzhen HospitalSouthern Medical UniversityShenzhen 518100Guangdong ProvinceChina The First Clinical Medical School Southern Medical UniversityGuangzhou 510515Guangdong ProvinceChina

BACKGROUND Many patients with ulcerative colitis(UC)do not respond well to,or tolerate conventional and biological *** is currently no consensus on the treatment of refractory *** have demonstrated that the selective Janus kinase 1 inhibitor upadacitinib,a small-molecule drug,is effective and safe for treating ***,no studies have revealed that upadacitinib is effective in treating refractory UC with primary nonresponse to infliximab and *** SUMMARY We report the case of a 44-year-old male patient with a chief complaint of bloody diarrhoea with mucus and pus,in addition to *** patient had recurrent disease after receiving mesalazine,prednisone,azathioprine,infliximab and vedolizumab over four *** on the endoscopic findings and pathological biopsy,the patient was diagnosed with refractory *** particular,the patient showed primary nonresponse to infliximab and *** on the patient’s history and recurrent disease,we decided to administer *** hospitalisation,the patient was received upadacitinib under our *** weeks after the initiation of upadacitinib treatment,the patient’s symptoms and endoscopic findings improved *** notable adverse reactions have been reported to *** Our case report suggests that upadacitinib may represent a valuable strategy for treating refractory UC with primary nonresponse.

关键词： Upadacitinib Refractory ulcerative colitis Primary nonresponse Infliximab Vedolizumab Case report

Progress in the treatment of advanced hepatocellular carcinoma with immune combination therapy

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World Journal of Gastrointestinal Oncology 2024年第2期16卷 273-286页

作者： Di Pan Hao-Nan Liu Peng-Fei Qu xiao Ma Lu-Yao Ma xiao-xiao Chen Yu-Qin Wang xiao-bing Qin Zheng-Xiang Han Department of Oncology The Affiliated Hospital of Xuzhou Medical UniversityXuzhou 221000Jiangsu ProvinceChina Department of Gastroenterology The Second Affiliated Hospital of Xuzhou Medical UniversityXuzhou 221000Jiangsu ProvinceChina Department of General Surgery The Affiliated Hospital of Xuzhou Medical UniversityXuzhou 221000Jiangsu ProvinceChina

Advanced hepatocellular carcinoma(HCC)is a severe malignancy that poses a serious threat to human *** to challenges in early diagnosis,most patients lose the opportunity for radical treatment when ***,recent advancements in cancer immunotherapy provide new directions for the treatment of *** instance,monoclonal antibodies against immune check-point inhibitors(ICIs)such as programmed cell death protein 1/death ligand-1 inhibitors and cytotoxic t-lymphocyte associated antigen-4 significantly improved the prognosis of patients with ***,tumor cells can evade the immune system through various *** the rapid development of genetic engineering and molecular biology,various new immunotherapies have been used to treat HCC,including ICIs,chimeric antigen receptor T cells,engineered cytokines,and certain cancer *** review summarizes the current status,research progress,and future directions of different immunotherapy strategies in the treatment of HCC.

关键词： Hepatocellular carcinoma Immunotherapies Immune checkpoint inhibitor Clinical efficacy Adverse reactions

Visible-light-driven photocatalysis degradation of antibiotic pollutants by La-doped CeO_(2) nanorods:synergy of La doping and oxygen vacancy

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Rare Metals 2024年第7期43卷 3134-3145页

作者： Shi-Hai Cao Jing-Ru Qu Yu-Qi Zhao Yun-Tong Sun wen-Tong Gao bing Han Yao Lu College of Environmental Engineering Nanjing Institute of TechnologyNanjing 211167China School of Materials Science and Engineering Nanjing Institute of TechnologyNanjing 211167China School of Chemistry Chemical Engineering and BiotechnologyNanyang Technological UniversitySingapore 637459Singapore Institute of Environmental Health and Ecological Security School of Environment and Safety EngineeringJiangsu UniversityZhenjiang 212013China Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment Suzhou University of Science and TechnologySuzhou215009China

Elemental doping is an effective strategy to enhance photocatalytic activity and extend the light absorption range of single-component *** this work,a series of La-doped CeO_(2) nanorods(La-CeO_(2)-x) with La content of 1 wt%-15 wt% are synthesized by a simple hydrothermal method and further used as photocatalyst for sulfamerazine(SMR) *** prepared La-CeO_(2)-x nanorods exhibit a great improvement in electron-hole pair migration and visible-light response due to the synergistic effect of abundant oxygen vacancies and heterogeneous elements(La).Consequently,La-CeO_(2)-x exhibited excellent visible-light photocatalytic performances and chemical stability for SMR degradation,the La-CeO_(2)-5 sample achieved the highest SMR degradation rate of 81%,which was 3.4 times higher than that of the original CeO_(2).Furthermore,three possible degradation pathways of SMR in La-CeO_(2) photocatalytic reactions were proposed by liquid chromatography-mass spectrometry ***,density functional theory calculations were carried out to provide an in-depth understanding of the structure-performance *** its excellent properties and better photocatalytic performance,this study demonstrates that La doping in CeO_(2) is an effective way to increase oxygen vacancy and improve the photochemical properties of photocatalysts.

关键词： CeO_(2)nanorod La-doped Photocatalysis Oxygen vacancy Sulfamerazine

A strained π-extended[10]cycloparaphenylene carbon nanoring

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Chinese Chemical Letters 2024年第5期35卷 171-174页

作者： Kang Wei Jiayu Li wen Zhang bing Yuan Ming-De Li Pingwu Du Key Laboratory of Precision and Intelligent Chemistry Anhui Laboratory of Advanced Photon Science and TechnologyDepartment of Materials Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province Shantou UniversityShantou 515063China

Herein,we report the facile synthesis of a highly strained hexabenzocoronene-containing carbon nanoring,cyclo[4]-paraphenylene[2]-2,11-hexabenzocoronenylene([4,2]CPHBC),as the segment of a[10,10]single-walled carbon nanotube([10,10]SWNT).[4,2]CPHBC was synthesized based on the platinummediated assembly of diborylbiphenyl and diborylhexabenzocoronene,forming a tetranuclear platinum complex,followed by reductive *** nanoring molecule was confirmed by NMR and HRMS,and its photophysical properties were studied using steady-state and time-resolved ***,the selective supramolecular host-guest interaction between[4,2]CPHBC and C_(60) was also investigated.

关键词： CPP Hexabenzocoronene Fullerene Supramolecular chemistry

P-and SV-wave dispersion and attenuation in saturated microcracked porous rock with aligned penny-shaped fractures

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Petroleum Science 2024年第1期21卷 143-161页

作者： Sheng-Qing Li wen-Hao Wang Yuan-Da Su Jun-Xin Guo xiao-Ming Tang School of Geosciences China University of Petroleum(East China)Qingdao 266580ShandongChina Laoshan National Laboratory Qingdao 266071ShangdongChina Guangdong Provincial Key Laboratory of Geophysical High-resolution Imaging Technology Southern University of Science and TechnologyShenzhen 518055GuangdongChina Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen 518055GuangdongChina

P-and SV-wave dispersion and attenuation have been extensively investigated in saturated poroelastic media with aligned ***,there are few existing models that incorporate the multiple wave attenuation mechanisms from the microscopic scale to the macroscopic ***,in this work,we developed a unified model to incorporate the wave attenuation mechanisms at different scales,which includes the microscopic squirt flow between the microcracks and pores,the mesoscopic wave-induced fluid flow between fractures and background(FB-WIFF),and the macroscopic Biot's global flow and elastic scattering(ES)from the *** Tang's modified Biot's theory and the mixed-boundary conditions,we derived the exact frequency-dependent solutions of the scattering problem for a single penny-shaped fracture with oblique incident P-and *** then developed theoretical models for a set of aligned fractures and randomly oriented fractures using the Foldy *** results indicated that microcrack squirt flow considerably influences the dispersion and attenuation of P-and SV-wave *** coupling effects of microcrack squirt flow with the FB-WIFF and ES of fractures cause much higher velocity dispersion and attenuation for P waves than for SV *** oriented fractures substantially reduce the attenuation caused by the FB-WIFF and ES,particularly for the ES attenuation of SV *** a comparison with existing models in the limiting cases and previous experimental measurements,we validated our model.

关键词： Aligned fractures P-and SV-wave Dispersion and attenuation Microcracked porous background FB-WIFF Elastic scattering Squirt flow

Effect of Artificial Electric Field Surface by Wave-Driven Triboelectricity on Anti-Bioadhesion for Riser Protection

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China Ocean Engineering 2024年第3期38卷 483-490页

作者： YI Peng QIU Hong-yuan LI Yong CAI Bao-ping Javad MOSTAGHIMI ZHANGwen-jie xiao wen-sheng College of Mechanical and Electrical Engineering China University of PetroleumQingdao 266580China CNOOC EnerTech Equipment Technology Co. Ltd.Tianjin 300450China Department of Mechanical&Industrial Engineering University of TorontoToronto ONM5S3G8Canada

Biofouling has been a persistent problem in marine riser system, resulting in energy waste and equipment damage. Inthis study, a kind of water wave-driven contact-mode flexible triboelectric nanogeneration has been prepared byusing graphene-doped PDMS as dielectric friction material. When the graphene content is 2%, the average outputvoltage can reach 46 V under the contact frequency 10 Hz. The flexible triboelectric nanogeneration encapsulationmodule is impinged by water waves to generate alternating microelectric field on the riser surface and destroy theadhesion conditions of microorganisms during the biofilm stage. In the biofouling experiments at different stages, thebiofouling area of the platymonas subcordiformis has been reduced by 53%, 62% and 61%. It provides a new ideafor effective treatment of biofouling of mussels, oysters and barnacles attached to risers.

关键词： wave-drive triboelectric nanogeneration alternating microelectric field anti-biofouling

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