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Catalytic asymmetric dearomative azo-Diels–Alder reaction of 2-vinlyindoles

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Chinese Chemical Letters 2024年第4期35卷 357-362页

作者： yu-Hang Miao Zheng-Xu Zhang Xu-Yi huang yuan-Zhao hua Shi-Kun jia Xiao Xiao Min-Can Wang Li-Ping Xu Guang-jian Mei Green Catalysis Center and College of ChemistryZhengzhou UniversityZhengzhou 450052China School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255000China Institute of Pharmaceutical Science and Technology Zhejiang University of TechnologyHangzhou 310014China

Due to the high electrophilic nature of azo-dienophiles, azo-Diels–Alder proceeds rapidly even without the need of a catalyst and is therefore regarded as the “click reaction”. This spontaneity causes strong background reaction and poses a daunting challenge to chemists for developing the catalytic asymmetric version. Reported herein is the first catalytic asymmetric dearomative azo-Diels–Alder reaction between2-vinylindoles and triazoledione. This protocol makes use of the high energy barrier of dearomatization to avert the strong background reaction of azo-Diels–Alder reaction, allowing the implementation of the projected reaction at ambient temperature. Density functional theory calculations have been performed to gain insights into the reaction mechanism and the origins of the enantioselectivity. By using this method,a variety of tetracyclic indole derivatives have been readily prepared in good to excellent yields and with excellent diastereo-and enantio–selectivities(33 examples, up to 97% yield and >99% ee, >20:1 dr).

关键词： Catalytic asymmetric dearomatization Azo-Diels–Alder reaction 2-Vinylindoles Chiral phosphoric acid Tetracyclic indole derivatives

High-rate lithium-ion battery performance of a ternary sea urchin-shaped CoNiO_(2)@NiP_(6)Mo_(18)/CNTs composites

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Journal of Energy Chemistry 2024年第9期96卷 516-525页

作者： Li-ping Cui Shuang Sun Kai yu Shu Zhang Mei-lin Wang jia-jia Chen Bai-bin Zhou Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of EducationSchool of Chemistry and Chemical EngineeringHarbin Normal UniversityHarbin 150025HeilongjiangChina State Key Laboratory of Physical Chemistry of Solid Surfaces Department of ChemistryCollege of Chemistry and Chemical EngineeringCollaborative Innovation Centre of Chemistry for Energy MaterialsXiamen UniversityXiamen 361005FujianChina

Bimetallic oxides are attractive anode materials for lithium-ion batteries(LIBs)due to their large theoretical ***,the low conductivity,short cycle life,and poor rate capability are the bottlenecks for their further *** overcome above issues,the basket-like polymolybdate(NiP_(6)Mo_(18))and carbon nanotubes(CNTs)were uniformly embedded on the urchin-shaped CoNiO_(2)nanospheres to yield a ternary composites CoNiO_(2)@NiP_(6)Mo_(18)/CNTs via electrostatic *** multi-level morphology of urchin spinules accelerates the diffusion rate of Li^(+);CNT improves the conductivity and enhances cycle stability of the material;and heteropoly acid contributes more redox activity ***,CoNiO_(2)@NiP_(6)Mo_(18)/CNTs as an anode of LIBs exhibits a high initial capacity(1396.7 mA h g^(−1)at 0.1 A g^(−1)),long-term cycling stability(750.2 mA h g^(−1)after 300 cycles),and rate performance(450.3 mA h g^(−1)at 2 A g^(−1)),which are superior to reported metallic oxides anode of *** density functional theory(DFT)and kinetic mechanism suggest that CoNiO_(2)@NiP_(6)Mo_(18)/CNTs delivers an outstanding pseudocapacitance and rapid Li^(+)diffusion behaviors,which is due to the rich surface area of the urchin-like CoNiO_(2)with the uniform embeddedness of NiP_(6)Mo_(18)and *** study provides a new idea for optimizing the performance of bimetallic oxides and developing high-rate lithium-ion battery composites.

关键词： Bi-metal oxides Transition metal oxides Polyoxometalates Nanocomposite LIBs

Collective Movement Simulation:Methods and Applications

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Machine Intelligence Research 2024年第3期21卷 452-480页

作者： hua Wang Xing-yu Guo Hao Tao Ming-Liang Xu School of Computer and Artificial Intelligence Zhengzhou UniversityZhengzhou450001China Engineering Research Center of Intelligent Swarm Systems Ministry of EducationZhengzhou450001China National Supercomputing Center in Zhengzhou Zhengzhou450001China China Ship Development and Design Center Wuhan430060China

Collective movement simulations are challenging and important in many areas,including life science,mathematics,physics,information science and public *** this survey,we provide a comprehensive review of the state-of-the-art techniques for collective movement *** start with a discussion on certain concepts to help beginners understand it more ***,we analyze the intelligence among different collective objects and the emphasis in different ***,we classify existing collective movement simulation methods into four categories according to their effects,namely versatility,accuracy,dynamic adaptability,and assessment feedback ***,we introduce five applications of layout optimization,emergency control,dispatching,unmanned systems,and other derivative ***,we summarize possible future research directions.

关键词： Collective movement simulation multiple objects multiple discipline simulation effect collective intelligence

Preparation of maximally-entangled states with multiple cat-state qutrits in circuit QED

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Frontiers of physics 2024年第3期19卷 239-251页

作者： Chui-Ping Yang jia-Heng Ni Liang Bin yu Zhang Yang yu Qi-Ping Su Department of Physics Hangzhou Normal UniversityHangzhou 311121China School of Physics Nanjing UniversityNanjing 210093China Institute for Quantum Science and Technology University of CalgaryAlberta T2N 1N4Canada

In recent years,cat-state encoding and high-dimensional entanglement have attracted much ***,previous works are limited to generation of entangled states of cat-state qubits(two-dimensional entanglement with cat-state encoding),while how to prepare entangled states of cat-state qutrits or qudits(high-dimensional entanglement with cat-state encoding)has not been *** here propose to generate a maximally-entangled state of multiple cat-state qutrits(three-dimensional entanglement by cat-state encoding)in circuit *** entangled state is prepared with multiple microwave cavities coupled to a superconducting flux ququart(a four-level quantum system).This proposal operates essentially by the cavity-qutrit dispersive *** circuit hardware resource is minimized because only a coupler ququart is *** higher intermediate level of the ququart is occupied only for a short time,thereby decoherence from this level is greatly suppressed during the state ***,the state preparation time does not depend on the number of the qutrits,thus it does not increase with the number of the *** an example,our numerical simulations demonstrate that,with the present circuit QED technology,the high-fidelity preparation is feasible for a maximally-entangled state of two cat-state ***,we numerically analyze the effect of the inter-cavity crosstalk on the scalability of this *** proposal is universal and can be extended to accomplish the same task with multiple microwave or optical cavities coupled to a natural or artificial four-level atom.

关键词： maximally-entangled states cat state qutrit circuit QED

Adsorptive interaction between typical VOCs and various topological zeolites:Mixture effect and mechanism

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Journal of Environmental Sciences 2024年第2期136卷 626-636页

作者： Bo yu hua Deng yuqin Lu Tingting Pan Wenpo Shan Hong He Center for Excellence in Regional Atmospheric Environment and Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Adsorption is one of the most feasible and effective methods to alleviate the volatile organic compounds(VOCs)***,the mixture effect and mechanism for competitive adsorption of VOCs on zeolites are barely *** this study,toluene,acetone,and ethyl acetate as prevalent VOCs species were removed by four potential zeolites(13X,USY,Beta,ZSM-5)in both single-and multi-component *** structure-property relationship between adsorbate-adsorbent pairs was revealed by X-ray diffraction,scanning electron microscopy,energy dispersive spectrometer,X-ray fluorescence,N_(2) adsorption and density function theory *** molecular polarity and volatility of VOCs species played key roles in adsorption and the dynamic uptakes were generally listed as follows:ethyl acetate>toluene>*** for the above VOCs mixtures,13X zeolite selectively adsorbed oxygenated VOCs rather than *** contrast,USY exhibited a preference to trap *** acetate could be readily enriched by ZSM-5 and Beta *** possible explanations and implications are discussed based on the subtle change in electron *** results obtained are vital for understanding the mixture effect of VOCs adsorption and may guide the selection of proper adsorbent for real applications.

关键词： Adsorption Zeolites VOCs Mixture effect DFT

WNT5A Regulated by miR154-5p is Associated with Angiopoiesis and Invasion of Placental Site Trophoblastic Tumor (PSTT)

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Biomedical and Environmental Sciences 2024年第4期37卷 423-427页

作者： ZHANG Sai CHEN Zhi Xian ZHANG Mo DU Yan ZHOU jia Yi WU Jing yu Yin hua CAO Qi ZHAO Hong Bo Obstetrics and Gynecology Hospital Fudan UniversityShanghai 200011China Shanghai Key Laboratory of Female Reproductive Endocrine Related Diseases Shanghai 200011China

Placental site trophoblastic tumor(PSTT),a rare gestational trophoblastic neoplasm(GTN),exhibits slow growth,late-onset metastasis,and chemotherapy insensitivity[1,2].The invasive capacity of trophoblasts induces angiogenesis in PSTT,yet the specific mechanism remains unclear[3].PSTT is typically resistant to chemotherapy and hysterectomy stands as the primary therapeutic choice for patients with an overall cure rate of approximately 75%-80%[4,5].Therefore,investigating the precise emergence and progression of PSTT is crucial,aiming to identify novel targets for diagnosis and therapy.

关键词： chemotherapy diagnosis metastasis

Zinc glycine chelate ameliorates DSS‑induced intestinal barrier dysfunction via attenuating TLR4/NF‑κB pathway in meat ducks

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Journal of Animal Science and Biotechnology 2024年第2期15卷 765-778页

作者： Yaqi Chang Ke Wang Guangmang Liu hua Zhao Xiaoling Chen Jingyi Cai Gang jia Institute of Animal Nutrition Key Laboratory for Animal Disease‑Resistance Nutrition of ChinaMinistry of EducationSichuan Agricultural UniversityChengdu 611130SichuanChina

Background Zinc glycine chelate(Zn-Gly)has anti-inflammation and growth-promoting properties;however,the mechanism of Zn-Gly contribution to gut barrier function in Cherry Valley ducks during intestinal inflammation is ***-hundred 1-day-old ducks were divided into 5 groups(6 replicates and 10 ducks per replicate)in a completely randomized design:the control and dextran sulfate sodium(DSS)groups were fed a corn-soybean meal basal diet,and experimental groups received supplements of 70,120 or 170 mg/kg Zn in form of *** DSS and treatment groups were given 2 mL of 0.45 g/mL DSS daily during d 15–21,and the control group received normal *** experiment lasted 21 *** Compared with DSS group,70,120 and 170 mg/kg Zn significantly increased body weight(BW),villus height and the ratio of villus to crypt,and significantly decreased the crypt depth of jejunum at 21 *** number of goblet cells in jejunal villi in the Zn-Gly group was significantly increased by periodic acid-Schiff *** with control,the content of intestinal permeability marker D-lactic acid(D-LA)and fluxes of fluorescein isothiocyanate(FITC-D)in plasma of DSS group significantly increased,and 170 mg/kg Zn supplementation significantly decreased the D-LA content and FITC-D *** with control,contents of plasma,jejunum endotoxin and jejunum pro-inflammatory factors IL-1β,IL-6 and TNF-αwere significantly increased in DSS group,and were significantly decreased by 170 mg/kg Zn *** Zn significantly increased the contents of anti-inflammatory factors IL-10,IL-22 and sIgA and IgG in ***-time PCR and Western blot results showed that 170 mg/kg Zn supplementation significantly increased mRNA expression levels of CLDN-1 and expression of OCLN protein in jejunum,and decreased gene and protein expression of CLDN-2 compared with DSS *** 120 mg/kg Zn significantly promoted the expressions of IL-22 and *** Zn-Gly supplementation sign

关键词： Cherry Valley ducks Growth performance Gut inflammation Intestinal barrier Zn-Gly

A new fabrication method for enhancing the yield of linear micromirror arrays assisted by temporary anchors

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Microsystems & Nanoengineering 2024年第3期10卷 169-180页

作者： Xingchen Xiao Ting Mao Yingchao Shi Kui Zhou jia Hao Yiting yu Ningbo Institute of Northwestern Polytechnical University College of Mechanical EngineeringNorthwestern Polytechnical University710072 Xi’anChina Key Laboratory of Micro/Nano Systems for Aerospace(Ministry of Education) Shaanxi Province Key Laboratory of Micro and Nanoelectromechanical SystemsNorthwestern Polytechnical University710072 Xi’anChina

As one of the most common spatial light modulators,linear micromirror arrays(MMAs)based on microelectromechanical system(MEMS)processes are currently utilized in many ***,two crucial challenges exist in the fabrication of such devices:the adhesion of silicon microstructures caused by anodic bonding and the destruction of the suspended silicon film due to residual *** solve these issues,an innovative processing method assisted by temporary anchors is *** approach effectively reduces the span of silicon microstructures and improves the Euler buckling limit of the silicon ***,these temporary anchors are strategically placed within the primary etching areas,enabling easy removal without additional processing *** a result,we successfully achieved wafer-level,high-yield manufacturing of linear MMAs with a filling factor as high as 95.1%.Demonstrating superior capabilities to those of original MMAs,our enhanced version boasts a total of 60 linear micromirror elements,each featuring a length-to-width ratio of 52.6,and the entire optical aperture measures 5 mm×6 *** linear MMA exhibits an optical deflection angle of 20.4°at 110 Vdc while maintaining exceptional deflection flatness and *** study offers a viable approach for the design and fabrication of thin-film MEMS devices with high yields,and the proposed MMA is promising as a replacement for digital micromirror devices(DMDs,by TI Corp.)in fields such as spectral imaging and optical communication.

关键词： mirror exceptional anodic

Gastrointestinal contrast-enhanced ultrasonography for diagnosis and treatment of peptic ulcer in children

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World Journal of Gastroenterology 2024年第7期30卷 705-713页

作者： yu-hua Zhang Zhi-hua Xu Shuang-Shuang Ni Hong-Xia Luo Department of Ultrasound The Second Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325000Zhejiang ProvinceChina

BACKGROUND The detection rate of peptic ulcer in children is improving,with development of diagnostic *** is the gold standard for the diagnosis of peptic ulcer,but it is an invasive *** contrast-enhanced ultrasonography(CEUS)has the advantages of being painless,noninvasive,nonradioactive,easy to use,and *** To investigate the clinical value of CEUS for diagnosis and treatment of peptic ulcer in *** We investigated 43 children with digestive tract symptoms in our hospital from January 2021 to June *** children were examined by routine ultrasound,gastrointestinal CEUS,and *** pathological results of gastroscopy were taken as the gold *** ultrasonography was performed before gastrointestinal *** ultrasound showed the thickness of the gastroduodenal wall,gastric peristalsis,and the adjacent organs and tissues around the abdominal *** CEUS recorded the thickness of the gastroduodenal wall;the size,location and shape of the ulcer;gastric peristalsis;and adjacent organs and tissues around the abdominal *** results of routine ultrasound and gastrointestinal ultrasound were compared with those of gastroscopy to evaluate the diagnostic results and coincidence rate of routine ultrasound and gastrointestinal *** children received informed consent from their guardians for *** study was reviewed and approved by the hospital medical ethics *** Among the 43 children,17(15 male,2 female)were diagnosed with peptic ulcer by *** were 26 children with nonpeptic *** were eight cases of peptic ulcer and 35 of nonpeptic ulcer diagnosed by conventional *** diagnostic coincidence rate of peptic ulcer in children diagnosed by conventional ultrasound was 79.1%(34/43),which was significantly different from that of gastroscopy(P=0.033).It indicates that the coincidence rate of gastrointestinal contrast-enhanc

关键词： Contrast-enhanced ultrasound Peptic ulcer Children Gastrointestinal tract Abdominal pain Acoustic contrast agent