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Palladium-catalyzed multi components oxy-aminofluorination and aminofluorination of gem-difluoroalkenes

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Chinese Chemical Letters 2024年第2期35卷 420-425页

作者： Fen Wu xin Li Junbiao Chang Dachang bai State Key Laboratory of Antiviral Drugs NMPA Key Laboratory for Research and Evaluation of Innovative DrugKey Laboratory of Green Chemical Media and ReactionsMinistry of EducationSchool of Chemistry and Chemical EngineeringPingyuan LaboratoryHenan Normal UniversityXinxiang 453007China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

Organofluorine compounds are widely used in the realm of drug discovery and material ***,we developed palladium catalyzed intermolecular aminofluorination and oxy-aminofluorination of gem‑difluoroalkenes with N-fluorobenzenesulfonimide(NFSI),in which NFSI was used as the nitrogen source and *** reaction provides an efficient and straightforward synthesis route of a series ofα-trifluoromethyl benzylic ***,three/four components oxy-aminofluorination processes were realized to giveα-trifluoromethyl benzylic ether with a terminal amino group,which proceed through C(sp^(3))-O bond cleavage of easily available ether and simultaneous introduced a fluorine,an amino and an oxy substituent in one pot with excellent *** divergent reactivity not only included the incorporation of one ether molecular,but also much more challenged two ether insertion with excellent selectivity through succession C(sp^(3))-O bonds *** protocol allows for concise synthesis of high value amines with fluoroalkyl-substituents and selectively transformation of easily available ethers by high-valent palladium catalysis.

关键词： Palladium Multi components Aminofluorination Oxy-aminofluorination C(sp^(3))-O bond cleavage

A low-noise,high-gain,and large-dynamic-range photodetector based on a JFET and a charge amplifier

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Frontiers of Information Technology & Electronic Engineering 2024年第2期25卷 316-322页

作者： Jinrong WANG Shuang'e WU Chengdong MI Yaner QIU xin'ai bai department of Physics Lyuliang UniversityLvliang033001China Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques South China University of TechnologyGuangzhou510640China

We demonstrate a low-noise,high-gain,and large-dynamic-range photodetector(PD)based on a junction field-effect transistor(JFET)and a charge amplifier for the measurement of quantum noise in Bell-state detection(BSD).Particular photodiode junction capacitance allows the silicon N-channel JFET 2sk152 to be matched to the noise requirement for charge amplifier *** electronic noise of the PD is effectively suppressed and the signal-to-noise ratio(SNR)is up to 15 dB at the analysis frequency of 2.75 MHz for a coherent laser power of 50.08µ*** combining of the inductor and capacitance,the alternating current(AC)and direct current(DC)branches of the PD can operate linearly in a dynamic range from 25.06µW to 17.50 *** PD can completely meet the requirements of SNR and dynamic range for BSD in quantum optics experiments.

关键词： Quantum noise Bell-state detection(BSD) Photodetector(PD) Junction field-effect transistor(JFET) Charge amplifier

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纯锆上离子注入钇和镧后的表面分析

物理学报 2005年第12期54卷 5914-5919页

作者：彭德全白新德潘峰孙辉清华大学材料科学与工程系北京100084

用金属蒸汽真空弧源,以40kV加速电压对纯锆样品分别进行了1016—1017/cm2的钇、镧离子注入,注入温度约为130℃.然后对注入样品进行表面分析.x射线光电子能谱分析表明,注入的钇以Y2O3形式存在,镧以La2O3形式存在.俄歇电子能谱表明,纯锆... 详细信息

用金属蒸汽真空弧源,以40kV加速电压对纯锆样品分别进行了1016—1017/cm2的钇、镧离子注入,注入温度约为130℃.然后对注入样品进行表面分析.x射线光电子能谱分析表明,注入的钇以Y2O3形式存在,镧以La2O3形式存在.俄歇电子能谱表明,纯锆基体表面的氧化膜厚度随着离子注入剂量的增加而增加,当离子注入剂量达到1017/cm2时,氧化膜的厚度达到了最大值.卢瑟福背散射显示镧层的厚度约为30nm,同时直接观察到当离子注入剂量为(La+Y)1017/cm2时,纯锆样品表面发生了严重的溅射.

关键词：纯锆钇和镧离子共注入卢瑟福背散射 x射线光电子能谱

Spark plasma sintering of tungsten-based WTaVCr refractory high entropy alloys for nuclear fusion applications

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 146-154页

作者： Yongchul Yoo Xiang Zhang Fei Wang xin Chen xing-Zhong Li Michael Nastasi bai Cui department of Mechanical&Materials Engineering University of Nebraska-LincolnLincolnNE 68588USA Nebraska Center for Materials and Nanoscience University of Nebraska-LincolnLincolnNE 68588USA department of Nuclear Engineering Texas A&M UniversityCollege StationTX 77843USA

W-based WTaVCr refractory high entropy alloys (RHEA) may be novel and promising candidate materials for plasma facing components in the first wall and diverter in fusion reactors. This alloy has been developed by a powder metallurgy process combining mechanical alloying and spark plasma sintering (SPS). The SPSed samples contained two phases, in which the matrix is RHEA with a body-centered cubic structure, while the oxide phase was most likely Ta2VO6through a combined analysis of X-ray diffraction (XRD),energy-dispersive spectroscopy (EDS), and selected area electron diffraction (SAED). The higher oxygen affinity of Ta and V may explain the preferential formation of their oxide phases based on thermodynamic calculations. Electron backscatter diffraction (EBSD) revealed an average grain size of 6.2μm. WTaVCr RHEA showed a peak compressive strength of 2997 MPa at room temperature and much higher micro-and nano-hardness than W and other W-based RHEAs in the literature. Their high Rockwell hardness can be retained to at least 1000°C.

关键词： refractory high entropy alloy plasma-facing material fusion reactor spark plasma sintering

Construction of shallow buried large-span metro stations using the small pipe roof-beam method

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Frontiers of Structural and Civil Engineering 2024年第1期18卷 122-136页

作者： Qian bai Wen ZHAO Yingda ZHANG Pengjiao JIA Xiangrui MENG Bo LU xin WANG Dazeng SUN School of Resources and Civil Engineering Northeastern UniversityShenyang 110819China Centre for Infrastructure Engineering and Safety School of Civil and Environmental EngineeringThe University of New South WalesNSW 2052Australia School of Rail Transportation Soochow UniversitySuzhou 215131China China Northeast Architectural design and Research Institute Co. Ltd.Shenyang 110006China

In relation to the Shifu Road Station project on Line 4 of the Shenyang Metro in China,a small-pipe roof-beam method for constructing subway stations is ***,a numerical simulation was performed to optimize the supporting parameters of the proposed method and determine the design ***,the deformation of the pipe roof and surface settlement during the construction process were ***,the surface settlement attributed to the excavation was studied through field monitoring,and the proposed method was compared with other *** results show that an increase in the pipe-roof spacing has little effect on the surface settlement and piperoof *** bearing capacity of the pipe roof can be efficiently utilized once the flexural stiffness reaches 2EI,and the flexural stiffness is not the dominant factor controlling the *** essential stages in controlling surface settlement are the excavations of the transverse pilot tunnels and the soil between *** final settlement value of the ground was 24.1 mm,resulting in a reduction in the construction period by at least five months while satisfying the control requirements.

关键词： subway station pipe-roof method surface settlement simulation on-site monitoring

Selective CO2 Electroreduction to Multi-Carbon Products on Organic-Functionalized CuO Nanoparticles by Local Micro-Environment Modulation

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NANO-MICRO LETTERS 2024年第1期16卷 1-13页

作者： Ren, Shan Cao, Xi Fan, Qikui Yang, Zhimao Wang, Fei Wang, xin bai, Licheng Yang, Jian Chinese Acad Sci Shenzhen Inst Adv Technol Mat Interfaces Ctr Shenzhen 518055 Guangdong Peoples R China Anhui Normal Univ Coll Chem & Mat Sci Key Lab Funct Mol Solids Minist Educ Wuhu 241002 Anhui Peoples R China Shenzhen Univ Coll Mat Sci & Engn Shenzhen 518071 Guangdong Peoples R China Xi An Jiao Tong Univ Sch Phys Xian 710049 Shaanxi Peoples R China

Surface functionalization of Cu-based catalysts has demonstrated promising potential for enhancing the electrochemical CO2 reduction reaction (CO2RR) toward multi-carbon (C2+) products, primarily by suppressing the parasitic hydrogen evolution reaction and facilitating a localized CO2/CO concentration at the electrode. Building upon this approach, we developed surface-functionalized catalysts with exceptional activity and selectivity for electrocatalytic CO2RR to C2+ in a neutral electrolyte. Employing CuO nanoparticles coated with hexaethynylbenzene organic molecules (HEB-CuO NPs), a remarkable C2+ Faradaic efficiency of nearly 90% was achieved at an unprecedented current density of 300 mA cm(-2), and a high FE (> 80%) was maintained at a wide range of current densities (100-600 mA cm(-2)) in neutral environments using a flow cell. Furthermore, in a membrane electrode assembly (MEA) electrolyzer, 86.14% FEC2+ was achieved at a partial current density of 387.6 mA cm(-2) while maintaining continuous operation for over 50 h at a current density of 200 mA cm(-2). In-situ spectroscopy studies and molecular dynamics simulations reveal that reducing the coverage of coordinated K & sdot;H2O water increased the probability of intermediate reactants (CO) interacting with the surface, thereby promoting efficient C-C coupling and enhancing the yield of C2+ products. This advancement offers significant potential for optimizing local micro-environments for sustainable and highly efficient C2+ production.

关键词： CO2 electroreduction to C2+ Neutral electrolyte Organic-functionalized CuO nanoparticles Local micro-environment modulation CARBON-DIOXIde ELECTROCHEMICAL REDUCTION

Tuning the band gap of the CIGS solar buffer layer Cd_(1-x)Zn_(x)S(x=0—1) to achieve high efficiency

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Optoelectronics Letters 2024年第2期20卷 100-106页

作者： TAN Zhiyuan XUE Yuming DAI Hongli WANG Luoxin HU Xiaofeng bai xin Institute of New Energy Intelligence Equipment School of Integrated Circuit Science and EngineeringTianjin University of TechnologyTianjin 300384China

To evaluate the impact of zinc sulfate(ZnSO_(4)) concentration on the structural properties of the films,Cd_(1-x)Zn_(x)S thin films were formed on glass substrates using chemical bath deposition(CBD) in this *** effect of ZnSO_(4) precursor concentration on the surface morphology,optical properties,and morphological structure of the Cd_(1-x)Zn_(x)S films was *** study the impact of zinc doping content on the performance metrics of Cu(In_(1-x)Ga_(x))Se_(2)(CIGS)cells in the experimental group and to improve the buffer layer thickness,simulations were run using one-dimensional solar cell capacitance simulator(SCAPS-1D) software.

关键词： CIGS (x) layer

Mesenchymal stem cells for repairing glaucomatous optic nerve

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 748-760页

作者： bai-Yu Hu Mei xin Ming Chen Ping Yu Liu-Zhi Zeng Eye School of Chengdu University of TCM Chengdu 610000Sichuan ProvinceChina department of Ophthalmology Chengdu First People’s HospitalChengdu 610095Sichuan ProvinceChina

Glaucoma is a common and complex neurodegenerative disease characterized by progressive loss of retinal ganglion cells(RGCs)and ***,there is no effective method to address the cause of RGCs ***,studies on neuroprotective strategies for optic neuropathy have increased in recent *** replacement and neuroprotection are major strategies for treating glaucoma and optic *** medicine research into the repair of optic nerve damage using stem cells has Received considerable *** cells possess the potential for multidirectional differentiation abilities and are capable of producing RGCfriendly microenvironments through paracrine *** article reviews a thorough researches of recent advances and approaches in stem cell repair of optic nerve injury,raising the controversies and unresolved issues surrounding the future of stem cells.

关键词： stem cell glaucoma retinal ganglion cell optic nerve axon regeneration

Bioinspired Hollow Mesoporous Silica Nanoparticles Coating on Titanium Alloy with Hierarchical Structure for Modulating Cellular Functions

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Journal of Bionic Engineering 2024年第3期21卷 1427-1441页

作者： Jiaxin Zhang He Liu Jincheng Wang Jing Shang Mingwei Xu Xiujie Zhu Chao Xu Haotian bai xin Zhao Orthopedic Institute of Jilin Province Orthopedic Medical CenterThe Second Hospital of Jilin UniversityChangchun130041China Key Laboratory of Bionic Engineering(Ministry of Education) Jilin UniversityChangchun130025China Institute of Structured and Architected Materials Liaoning Academy of MaterialsShenyang110167China

3D-printed Porous Titanium Alloy Implants(pTi),owing to their biologically inertness and relatively smooth surface morphology,adversely affect the biological functions of surrounding *** address the challenges,constructing a bioinspired interface that mimics the hierarchical structure of bone tissue can enhance the cellular functions of *** this context,Hollow Mesoporous Silica Nanoparticles(HMSNs),renowned for their unique physicochemical properties and superior biocompatibility,offer a promising direction for this *** this research,the initially synthesized HMSNs were used to construct a“hollow-mesoporous-macroporous”hierarchical bioinspired coating on the pTi surface through the Layer-by-Layer ***,diverse morphologies of coatings were established by adjusting the deposition strategy of PDDA/HMSNs on the pTi surface(pTi-HMSN-2,pTi-HMSN-4,pTi-HMSN-6).A range of techniques were employed to investigate the physicochemical properties and regulation of cellular biological functions of the diverse HMSN coating ***,the pTi-HMSN-4 and pTi-HMSN-6 groups exhibited the uniform coatings,leading to a substantial enhancement in surface roughness and ***,the coating constructed strategy of pTi-HMSN-4 possessed commendable *** on the aforementioned findings,both pTi-HMSN-4 and pTi-HMSN-6 facilitated the adhesion,spreading,and pseudopodia extension of BMSCs,which led to a notable upsurge in the expression levels of vinculin protein in *** analysis indicates that the coating,when PDDA/HMSNs are deposited four times,possesses favorable overall *** research will provide a solid theoretical basis for the translation of HMSN bioinspired coatings for orthopedic implants.

关键词： Hollow mesoporous silica nanoparticles Bioinspired coating Titanium alloy Hierarchical structure Cellular functions