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New strategies for asymmetric photocatalysis: asymmetric organocatalytic/photoredox relay catalysis for efficient synthesis of polycyclic compounds containing vicinal amino alcohols

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Science China Chemistry 2024年第3期67卷 945-952页

作者： Jia-lu Zhang Wen-Bo He Xiu-Qin Hu peng-fei Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China State Key Laboratory of Veterinary Etiological Biology College of Veterinary MedicineLanzhou UniversityLanzhou Veterinary Research InstituteChinese Academy of Agricultural SciencesLanzhou 730000China MOE Frontiers Science Center for Rare Isotopes Lanzhou UniversityLanzhou 730000China

An asymmetric catalytic strategy in photocatalysis utilizing a chirality-induced approach through an organocatalytic/photoredox relay catalysis strategy is successfully achieved for the rapid construction of polycyclic compounds containing vicinal amino alcohols in a one-pot protocol. This methodology facilitates the efficient synthesis of diverse substituted polycyclic tetrahydroquinoline and benzofuran-derived vicinal amino alcohols, each containing five consecutive chiral centers, with high yields,excellent diastereoselectivities and enantioselectivities(up to 95% yield, >20:1 dr and 98% ee), under mild reaction conditions driven by sequential bifunctional squaramide organocatalyst-catalyzed [4+2] annulation and photocatalyst-catalyzed ketyl radical addition cyclization reaction process. Furthermore, investigations into the stereoselectivity mechanism and high-resolution mass spectrometry(HRMS) experiments on free radical trapping have provided evidence for elucidating the detailed mechanism of chirality-induced processes and chiral intermediate conversions in this procedure.

关键词： enantioselective photocatalysis asymmetric organocatalytic/photocatalysis relay catalysis five consecutive chiral centers chirality-induced strategy chirality vicinal amino alcohols

Well-dispersed Sb particles embedded on N-doped carbon nanofibers toward high-performance Li-ion battery

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Rare Metals 2024年第7期43卷 2994-3006页

作者： Ying Li Yi-Han Zhao lu-lu Zhao peng-fei Wang Ying Xie Ting-Feng Yi School of Materials Science and Engineering Northeastern UniversityShenyang 110819China Key Laboratory of Dielectric and Electrolyte Functional Material Hebei Province School of Resources and MaterialsNortheastern University at QinhuangdaoQinhuangdao 066004China Key Laboratory of Functional Inorganic Material Chemistry Ministry of EducationSchool of Chemistry and Materials ScienceHeilongjiang UniversityHarbin 150080China

The alloy-type material Sb is widely used in the anode materials of lithium-ion batteries(LIBs)due to its high theoretical specific ***,its serious volume expansion problem during alloying/dealloying of Li~+limits its practical *** this work,C-Sb composite was constructed as anode material of LIBs by electrospinning route for the first time,Sb was introduced into the polyacrylonitrile-based hard carbon and coal tar pitch-based soft carbon composite amorphous carbon fiber with a diameter of 300-600 nm,which realized high cycling *** C-Sb-2(the mass ratio of polyacrylonitrile to Sb source is 1:2)electrode displayed charge capacities of 1098.5,930.3,841.7,753.5,643.9 and 545.8 mAh·g^(-1)at 0.1,0.2,0.3,0.5,1 and 2 A·g^(-1),*** when the current density returned to 0.1 A·g^(-1),the charge capacity was 939.3 mAh·g^(-1),revealing good stability and *** introduction of Sb into the amorphous carbon improved its conductivity and addressed the volume expansion issue of high specific capacity Sb during charge/***-situ XRD analysis confirmed the high reversibility of the C-Sb-2 during charging and *** functional theory(DFT)calculations revealed the gradual enhancement of the interface interaction between Sb_(x)Li_(y) and amorphous carbon(AMC)with increasing lithium content,contributing to the anchoring of alloy nanoparticles on the AMC surface and buffering the volume change of the ***,the gradual lithiation of Sb facilitated the electron transfer from Sb_(x)Li_(y) to *** findings hold promise for designing lithium storage materials with exceptional performance,highlighting the potential of C-Sb composites as anode materials for efficient next-generation lithium storage.

关键词： Li-ion battery Metallic Sb Carbon Electrospinning Cycling stability

Mid-infrared computational temporal ghost imaging

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Light(Science & Applications) 2024年第6期13卷 1088-1097页

作者： Han Wu Bo Hu lu Chen fei peng Zinan Wang Goery Genty Houkun Liang College of Electronics and Information Engineering Sichuan UniversityChengduSichuan610064China College of Electrical Engineering Sichuan UniversityChengduSichuan610064China Key Lab of Optical Fiber Sensing&Communications University of Electronic Science&Technology of ChinaChengduSichuan611731China Laboratory of Photonics Tampere UniversityFI-33014TampereFinland

Ghost imaging in the time domain allows for reconstructing fast temporal objects using a slow *** technique involves correlating random or pre-programmed probing temporal intensity patterns with the integrated signal measured after modulation by the temporal ***,the implementation of temporal ghost imaging necessitates ultrafast detectors or modulators for measuring or pre-programming the probing intensity patterns,which are not available in all spectral regions especially in the mid-infrared ***,we demonstrate a frequency downconversion temporal ghost imaging scheme that enables to extend the operation regime to arbitrary wavelengths regions where fast modulators and detectors are not *** approach modulates a signal with temporal intensity patterns in the near-infrared and transfers the patterns to an idler via difference-frequency generation in a nonlinear crystal at a wavelength where the temporal object can be *** a proof-of-concept,we demonstrate computational temporal ghost imaging in the mid-infrared with operating wavelength that can be tuned from 3.2 to 4.3μ*** scheme is flexible and can be extended to other *** results introduce new possibilities for scan-free pump-probe imaging and the study of ultrafast dynamics in spectral regions where ultrafast modulation or detection is challenging such as the mid-infrared and THz regions.

关键词： ghost Ghost scheme

Thermal and ignition properties of hexanitrostilbene(HNS) microspheres prepared by droplet microfluidics

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Defence Technology（防务技术） 2023年第7期25卷 166-173页

作者： Rui-shan Han fei-peng lu Fang Zhang Yan-lan Wang Mi Zhou Guo-sheng Qin Jian-hua Chen Hai-fu Wang En-yi Chu State Key Laboratory of Explosion and Technology Beijing Institute of TechnologyBeijing100081China Science and Technology on Applied Physical Chemistry Laboratory Shaanxi Applied Physics-Chemistry Research InstituteXi'an710061ShaanxiChina

HNS-IV(Hexanitrostilbene-IV) is the main charge of the exploding foil initiators(EFI), and the microstructure of the HNS will directly affect its density, flowability, sensitivity, and stability. HNS microspheres were prepared using droplet microfluidics, and the particle size, morphology, specific surface area, thermal performance, and ignition threshold of the HNS microspheres were characterized and tested. The results shown that the prepared HNS microspheres have high sphericity, with an average particle size of 20.52 μm(coefficient of variation less than 0.2), and a specific surface area of 21.62 m^(2)/g(6.87 m^(2)/g higher than the raw material). Without changing the crystal structure and thermal stability of HNS-IV, this method significantly enhances the sensitivity of HNS-IV to short pulses and reduces the ignition threshold of the slapper detonator to below 1000 V. This will contribute to the miniaturization and low cost of EFI.

关键词： Microfluidics HNS microspheres Thermal stability Ignition threshold

Spin effect on redox acceleration and regioselectivity in Fe-catalyzed alkyne hydrosilylation

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National Science Review 2024年第2期11卷 155-167页

作者： peng He Meng-Yang Hu Jin-Hong Li Tian-Zhang Qiao Yi-Lin lu Shou-fei Zhu Frontiers Science Center for New Organic Matter State Key Laboratory and Institute of Elemento-Organic Chemistry Nankai University

Iron catalysts are ideal transition metal catalysts because of the Earths abundant, cheap, biocompatible features of iron salts. Iron catalysts often have unique open-shell structures that easily undergo spin crossover in chemical transformations, a feature rarely found in noble metal catalysts. Unfortunately, little is known currently about how the open-shell structure and spin crossover affect the reactivity and selectivity of iron catalysts, which makes the development of iron catalysts a low efficient trial-and-error program. In this paper, a combination of experiments and theoretical calculations revealed that the iron-catalyzed hydrosilylation of alkynes is typical spin-crossover catalysis. Deep insight into the electronic structures of a set of well-defined open-shell active formal Fe(0) catalysts revealed that the spin-delocalization between the iron center and the 1,10-phenanthroline ligand effectively regulates the iron center's spin and oxidation state to meet the opposite electrostatic requirements of oxidative addition and reductive elimination, respectively,and the spin crossover is essential for this electron transfer process. The triplet transition state was essential for achieving high regioselectivity through tuning the nonbonding interactions. These findings provide an important reference for understanding the effect of catalyst spin state on reaction. It is inspiring for the development of iron catalysts and other Earth-abundant metal catalysts, especially from the point of view of ligand development.

关键词： spin effect spin-delocalization spin crossover iron-catalysis alkyne hydrosilylation

Impairment of Autophagic Flux After Hypobaric Hypoxia Potentiates Oxidative Stress and Cognitive Function Disturbances in Mice

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Neuroscience Bulletin 2024年第1期40卷 35-49页

作者： Shuhui Dai Yuan Feng Chuanhao lu Hongchen Zhang Wenke Ma Wenyu Xie Xiuquan Wu peng luo Lei Zhang fei fei Zhou fei Xia Li Department of Neurosurgery Xijing HospitalFourth Military Medical UniversityXi'an 710000China National Translational Science Center for Molecular Medicine and Department of Cell Biology Fourth Military Medical UniversityXi'an 710000China Department of Neurosurgery The Central Hospital of BaojiBaoji 721000China Department of Ophthalmology Xijing HospitalFourth Military Medical UniversityXi'an 710000China

Acute hypobaric hypoxic brain damage is a potentially fatal high-altitude *** plays a critical role in ischemic brain injury,but its role in hypo-baric hypoxia(HH)remains *** we used an HH chamber to demonstrate that acute HH exposure impairs autophagic activity in both the early and late stages of the mouse brain,and is partially responsible for HH-induced oxidative stress,neuronal loss,and brain *** autophagic agonist rapamycin only promotes the initiation of *** proteome analysis,a screen showed that protein dynamin2(DNM2)potentially regulates autophagic *** of DNM2 significantly increased the formation of autolysosomes,thus maintaining autophagic flux in combination with ***,the enhancement of autophagic activity attenuated oxidative stress and neurological deficits after HH *** results contribute to evidence supporting the conclusion that DNM2-mediated autophagic flux represents a new therapeutic target in HH-induced brain damage.

关键词： Autophagy-Proteomics Oxidative stress Hypobaric hypoxia-Brain injury

Colonoscopy-assisted removal of an impaction foreign body at the rectosigmoid junction: A case report

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World Journal of Clinical Cases 2024年第11期12卷 1990-1995页

作者： peng-fei Zhou Jin-Gen lu Jia-Dong Zhang Jia-Wen Wang Department of Anorectal Surgery Longhua Hospital Shanghai University of Traditional Chinese MedicineShanghai 200000China

BACKGROUND When an anorectal foreign body is found,its composition and shape should be evaluated,and a timely and effective treatment plan should be developed based on the patient's symptoms to avoid serious complications such as intestinal perforation caused by displacement of the foreign *** SUMMARY A 54-year-old male was admitted to our outpatient clinic on June 3,2023,due to a rectal foreign body that had been embedded for more than 24 *** patient reported using a glass electrode tube to assist in the recovery of prolapsed hemorrhoids,however,the electrode tube was inadvertently inserted into the anus and could not be removed by the *** hospitalization,the patient underwent surgery,and the foreign body was dragged into the rectum with the aid of *** anus was dilated with a comb-type pulling hook and an anal fistula pulling hook to widen the anus and remove the foreign body,and the local anal symptoms were then relieved with topical *** patient was allowed to eat and drink,and an entire abdominal Computed tomography(CT)and colonoscopy were reviewed 3 d after *** revealed no foreign body residue and colonoscopy showed no metal or other residues in the colon and rectum,and no apparent intestinal tract *** The timeliness and rationality of the surgical and therapeutic options for this patient were based on a literature review of the clinical signs and conceivable conditions in such *** type,material and the potential risks of rectal foreign bodies should be considered.

关键词： Foreign body impaction Surgical therapy Rectum-sigmoid colon Colonoscopy Case report

Comparison of clinical features and outcomes of proliferative,fibrotic,and mixed subtypes of IgG4-related disease:A retrospective cohort study

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Chinese Medical Journal 2024年第3期137卷 303-311页

作者： Linyi peng Xinlu Zhang Jiaxin Zhou Jieqiong Li Zheng Liu Hui lu Yu peng Yunyun fei Yan Zhao Xiaofeng Zeng Wen Zhang Department of Rheumatology and Clinical Immunology Peking Union Medical College HospitalNational Clinical Research Center for Dermatologic and Immunologic DiseasesState Key Laboratory of Complex Severe and Rare DiseasesThe Ministry of Education Key LaboratoryBeijing 100730China Institute of Clinical Medicine Peking Union Medical College Hospital(PUMCH)Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China

Background:Immunoglobulin G4-related disease(IgG4-RD)is a recently recognized immune-mediated disorder that can affect almost any organ in the human ***4-RD can be categorized into proliferative and fibrotic subtypes based on patients’clinicopathological *** study aimed to compare the clinical manifestations,laboratory findings,and treatment outcomes of IgG4-RD among different ***:We prospectively enrolled 622 patients with newly diagnosed IgG4-RD at Peking Union Medical College Hospital from March 2011 to August *** patients were divided into three groups according to their clinicopathological characteristics:proliferative,fibrotic,and mixed *** compared demographic features,clinical manifestations,organ involvement,laboratory tests,and treatment agents across three *** then assessed the differences in treatment outcomes among 448 patients receiving glucocorticoids alone or in combination with ***,risk factors of relapse were revealed by applying the univariate and multivariate Cox regression ***:We classified the 622 patients into three groups consisting of 470 proliferative patients,55 fibrotic patients,and 97 mixed patients,*** found that gender distribution,age,disease duration,and frequency of allergy history were significantly different among *** terms of organ involvement,submandibular and lacrimal glands were frequently involved in the proliferative subtype,while retroperitoneum was the most commonly involved site in both fibrotic subtype and mixed *** comparison of laboratory tests revealed that eosinophils(P=0.010),total IgE(P=0.006),high-sensitivity C-reactive protein(P<0.001),erythrocyte sedimentation rate(P<0.001),complement C4(P<0.001),IgG(P=0.001),IgG1(P<0.001),IgG4(P<0.001),and IgA(P<0.001),at baseline were significantly different among three *** with proliferative and mixed subtypes,the fibrotic subtype showed the

关键词： IgG4-related disease Proliferative subtype Fibrotic subtype Clinical features Treatment outcome

Strong-coupling superconductivity with Tc above 70 K in Be-decorated monolayer T-graphene

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 99-105页

作者： Liu Yang peng-fei Liu Hao-Dong Liu Ya-Ping Li Na Jiao Hong-Yan lu Bao-Tian Wang Ping Zhang School of Physics and Physical Engineering Qufu Normal UniversityQufu 273165China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Spallation Neutron Source Science Center Dongguan 523803China Institute of Applied Physics and Computational Mathematics Beijing 100088China

Using first-principles calculations,we predict a new type of two-dimensional(2D)beryllium(Be)-decorated T-graphene named BeC_(2),where Be atoms are inserted into C–C bonds linking the carbon tetrarings of *** band structure shows that BeC_(2)is metallic,thus,the possible phonon-mediated superconductivity is explored based on the Eliashberg *** calculated electron-phonon coupling(EPC)constantλis up to 4.07,and the corresponding superconducting critical temperature(Tc)is 72.1 K,approaching the liquid nitrogen *** reason for the high Tc is the strong *** it is proved to be an anisotropic single-gap superconductor by analyzing the superconducting gap?kof BeC_(2).The electronic susceptibility calculation shows strong nesting effect in BeC_(2).Since rare 2D superconductors show such a strong EPC constantλwhich originates from the coupling between electrons in C-pzorbital and in-plane vibrations of Be and C atoms,the predicted BeC_(2)provides a new platform for investigating strong EPC 2D superconductor.

关键词： two-dimensional carbon-based superconductor electron-phonon coupling strong coupling high superconducting critical temperature