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Enantioselective Alkylation of Aldehydes with Organoborons Enabled by Nickel/N-Heterocyclic Carbene Catalysis

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Chinese Journal of Chemistry 2024年第18期42卷 2161-2165页

作者： Song-Yang Liu zi-chao Wang Shi-liang Shi College of Chemistry and Material Science Shanghai Normal University100 Guilin RoadShanghai 200234China State Key Laboratory of Organometallic Chemistry Shanghai Institute of rganic ChemitryUniversity of Chinee Academy of Scienc Chinese Academy of Sciences345 Lingling RoadShanghai 200032China

Transition-metal-catalyzed asymmetric alkylation of aldehydes represents a straightforward strategy for the synthesis of chiral secondary ***,efficient methods using organoborons as coupling reagents are ***,we report a highly enantioselective nickel-catalyzed alkylation reaction of aldehydes,using readily available alkylborons as nucleophiles.A wide variety of chiral secondary alcohols were prepared from commercially available aldehydes with high *** key to the excellent enantioselectivity and chemoselectivity was the employment of a bulky C2-symmetric chiral NHC *** protocol features excellent enantiocontrol,mild conditions,and good functional group compatibility.

关键词： Enantioselective alkylation Nickel catalysis N-Heterocyclic carbene Organoborons Chiral alcohols Asymmetric catalysis C-C coupling Synthetic methods

Ultrahard X-ray multifunctional application beamline at the SSRF

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Nuclear Science and Techniques 2024年第6期35卷 14-25页

作者： Ke Yang Zhao-Hui Dong Chun-Yin Zhou zi-Long Zhao Dong-Xu liang Sai-chao Cao Ai-Guo Li Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China

The ultrahard X-ray multifunctional application beamline(BL12SW)is a phase-II beamline project at the Shanghai Syn-chrotron Radiation *** primary X-ray techniques used at the beamline are high-energy X-ray diffraction and imaging using white and monochromatic *** main scientific objectives of ultrahard X-ray beamlines are focused on two research *** is the study of the structural properties of Earth’s interior and new materials under extreme high-temperature and high-pressure conditions,and the other is the characterization of materials and processes in near-real service *** beamline utilizes a superconducting wiggler as the light source,with two diamond windows and SiC discs to filter out low-energy light(primarily below 30 keV)and a Cu filter assembly to control the thermal load entering the subsequent optical *** beamline is equipped with dual *** first was a meridional bending Laue monochromator cooled by liquid nitrogen,achieving a full-energy coverage of 30-162 *** second was a sagittal bending Laue monochromator installed in an external building,providing a focused beam in the horizontal direction with an energy range of 60-120 *** were four experimental hutches:two large-volume press experimental hutches(LVP1 and LVP2)and two engineering material experimental hutches(ENG1 and ENG2).Each hutch was equipped with various near-real service conditions to satisfy different *** example,LVP1 and LVP2 were equipped with a 200-ton DDIA press and a 2000-ton dual-mode(DDIA and Kawai)press,***1 and ENG2 provide in situ tensile,creep,and fatigue tests as well as high-temperature *** June 2023,the BL12SW has been in trial *** is expected to officially open to users by early 2024.

关键词： Shanghai Synchrotron Radiation Facility Ultrahard X-ray High energy diffraction High energy imaging Engineering materials Earth science

Resource allocation for D2D-assisted haptic communications

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Digital Communications and Networks 2024年第1期10卷 63-74页

作者： Yan Wu chao Yue Yang Yang liang Ao College of Telecommunication Engineering Army Engineering University of PLANanjing210000China

Haptic communications is recognized as a promising enabler of extensive services by enabling real-time haptic control and feedback in remote environments,e.g.,teleoperation and autonomous *** the strict transmission requirements on reliability and latency,Device-to-Device(D2D)communications is introduced to assist haptic *** particular,the teleoperators with poor channel quality are assisted by auxiliaries,and each auxiliary and its corresponding teleoperator constitute a D2D ***,the haptic interaction and the scarcity of radio resources pose severe challenges to the resource allocation,especially facing the sporadic packet ***,the contentionbased access scheme is applied to achieve low-latency transmission,where the resource scheduling latency is omitted and users can directly access available *** this context,we derive the reliability index of D2D pairs under the contention-based access scheme,i.e.,closed-loop packet error ***,the reliability performance is guaranteed by bidirectional power control,which aims to minimize the sum packet error probability of all D2D *** game theory is introduced to solve the problem with low ***,a distributed power control algorithm based on synchronous log-linear learning is proposed to converge to the optimal Nash *** results demonstrate the superiority of the proposed learning algorithm.

关键词： Haptic communications D2D Power control Contention-based access Potential game

Screening of transition metal oxides for electrocatalytic nitrate reduction to ammonia at large currents

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Nano Research 2024年第5期17卷 3902-3910页

作者： Qiongfei Wu Weijie Zhu Dongxu Ma chao liang Zhoucheng Wang Hanfeng liang State Key Laboratory of Physical Chemistry of Solid Surfaces Tan Kah Kee Innovation LaboratoryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China College of Chemical Engineering Tianjin UniversityTianjin 300072China

Electrochemical nitrate reduction reaction(NO_(3)RR)towards ammonia,as an emerging and appealing technology alternative to the energy-intensive Haber-Bosch process and inefficient nitrogen reduction reaction,has recently aroused wide concern and ***,the current research of the NO_(3)RR towards ammonia lacks the overall performance comparison of various *** this,we here make a comparison of 12 common transition metal oxide catalysts for the NO_(3)RR under a high cathodic current density of 0.25 A·cm^(-2),wherein Co_(3)O_(4) catalyst displays the highest ammonia Faradaic efficiency(85.15%)and moderate activity(ca.-0.25 V *** hydrogen electrode).Other external factors,such as nitrate concentrations in the electrolyte and applied potential ranges,have also been specifically investigated for the NO_(3)RR.

关键词： nitrate reduction reaction ammonia production transition metal oxides Co_(3)O_(4)

Crust and Upper Mantle Density Structures beneath the Eastern Tianshan Region and Its Tectonic Implications

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Journal of Earth Science 2024年第3期35卷 828-838页

作者： Yiming Liu chao Chen Qing liang Zhengwang Hu Hubei Subsurface Multi-Scale Imaging Key Laboratory School of Geophysics and GeomaticsChina University of GeosciencesWuhan 430074China

The deformation mechanisms of the Tianshan orogenic belt(TOB)are one of the most important unresolved issues in the collision of the Indian and Eurasian *** better understand the lithospheric deformation of the eastern Tianshan orogenic belt,we combined the S-wave tomography and gravity data to develop a three-dimensional(3D)density model of the crust and upper mantle beneath the eastern Tianshan *** show that the crust of the eastern Tianshan is mainly characterized by positive density anomalies,revealing widespread subduction-related magmatism during the *** however have also observed extensive low-density anomalies beneath the eastern Tianshan at depths deeper than~100 km,which is likely linked to a relatively hot *** most fundamental differences of the lithosphere within the eastern Tianshan occur in the uppermost *** uppermost mantle layers in the Bogda Shan and Harlik Shan are relatively *** is likely associated with an eclogite body in the uppermost *** most significant negative anomaly of the uppermost mantle is however found in the Jueluotage tectonic belt and the central Tianshan Block and is possibly associated with depleted mantle *** suggest that these differences related to compositional changes may control the strength of the lithospheric mantle and have affected the uplift of the northern and southern segments of the eastern Tianshan after the Permian.

关键词： constrained inversion gravity anomaly three-dimensional lithospheric density structure eastern Tianshan geodynamics geophysics.

High-Performance Inverted Perovskite Solar Cells with Sol-Gel-Processed Sliver-Doped NiOx Hole Transporting Layer

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Energy & Environmental Materials 2024年第4期7卷 205-214页

作者： Haibin Wang Zhiyin Qin Xinjian Li Chun Zhao chao liang School of Advanced Technology Xi'an Jiaotong-Liverpool University Department of Electrical Engineering and Electronics University of Liverpool School of Humanities and Social Sciences Xi'an Jiaotong-Liverpool University Key Laboratory of Materials Physics of Ministry of Education School of Physics and Microelectronics Zhengzhou University MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter School of Physics National Innovation Platform (Center) for Industry-Education Integration of Energy Storage Technology Xi'an Jiaotong University

Nickel oxide （NiOx） has been established as a highly efficient and stable holetransporting layer （HTL） in perovskite solar cells （PSCs）.However,existing deposition methods for NiOxhave been restricted by high-vacuum processes and fail to address the energy level mismatch at the NiOx/perovskite interface,which has impeded the development of PSCs.

关键词： Ag-NiOX/NiOX hole transporting layer inverted perovskite solar cells

Enhanced degradation of refractory organics in ORR-EO system with a blue TiO_(2)nanotube array modified Ti-based Ni-Sb co-doped SnO_(2)anode

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Chinese Chemical Letters 2024年第8期35卷 391-395页

作者： Yifen He chao Qu Na Ren Dawei liang Department of Materials Chemistry School of Materials Science&EngineeringBeihang UniversityBeijing 102206China Department of Environmental Science Faculty of Environment&LifeBeijing University of TechnologyBeijing 100124China

Recently,a novel 2-electron oxygen reduction reaction(ORR)based electro-oxidation(EO)system was developed,which utilizes a H_(2)O_(2)generation cathode instead of H_(2)evolution cathode.A Ti-based Ni-Sb co-doped SnO_(2)(Ti/NATO)anode was selected for efficient degradation of refractory organics and O_(3)*** synergistic reaction of O3/H_(2)O_(2)further accelerated the generation of hydroxyl radicals(·OH)in the ORR-EO ***,the catalytic activity and long-term effectiveness of the Ti/NATO anode limited the large-scale application of the ORR-EO *** this study,a blue TiO_(2)nanotube array(blue-TiO_(2)-NTA)inter-layer was introduced into the fabrication process between the Ti substrate and NATO catalyst *** to the Ti/NATO anode,the Ti/blue-TiO_(2)-NTA/NATO anode achieved higher efficiency of organic removal and O_(3)***,the accelerated lifetime of the Ti/blue-TiO_(2)-NTA/NATO anode was increased by 7 times compared to the Ti/NATO *** combined with CNTs-C/PTFE air cathode in ORR-EO system,all anodic oxidation and O_(3)/H_(2)O_(2)processes achieved higher•OH *** 92%of TOC in leachate bio-effluent was effectively eliminated with a relatively low energy cost of 45 kWh/t.

关键词： Electro-oxidation Blue TiO_(2)nanotube array O_(3)/H_(2)O_(2)process Refractory organics Leachate bio-effluent

Microstructural evolution,mechanical properties and degradation mechanism of PS-PVD quasi-columnar thermal barrier coatings exposed to glassy CMAS deposits

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Rare Metals 2024年第7期43卷 3329-3340页

作者： zi-Yue Yu liang-liang Wei Xing-Ye Guo Bao-Peng Zhang Qing He Hong-Bo Guo School of Materials Science and Engineering Beihang UniversityBeijing100191China Key Laboratory of High-Temperature Structure Materials and Protective Coatings(Ministry of Industry and Information Technology) Beihang UniversityBeijing 100191China Surface Engineering Research Institute Chinese Academy of Agricultural Mechanization SciencesBeijing 100083China

Thermal barrier coatings(TBCs) applied in aeroengines tend to be attacked by molten calcia-magnesiaalumino-silicate(CMAS) at high operating ***-stabilized zirconia(YSZ) coatings with quasicolumnar microstructure were fabricated by plasma spray physical vapor deposition(PS-PVD) *** chemic al changes,micros tructural transform ation,mechanical properties and degradation mechanisms of the CM AS-interacted TBCs in the thermal cycling tests were *** YSZ grains were dissolved in the CMAS melts,and then the ZrO_(2) grains were reprecipitated with spherical shape,accompanying with phase transformation from tetragonal(t) to monoclinic(m).The thermal cycling tests reveal that the YSZ coating fails at the early stage due to the attack of *** fractures in intracolumns lead to partial spallation of the *** failure of the coating occurs at the interfaces between thermally grown oxides(TGO) layer and YSZ topcoat;especially,the hardness and Young's modulus of the YSZ coatings increase intensively,as the coatings were infiltrated by the CMAS for a long time.

关键词： CMAS Thermal barrier coatings Young's modulus Thermal cycling behavior PS-PVD

A low-melting-point metal doping strategy for the synthesis of small-sized intermetallic Pt_(5)Ce fuel cell catalysts

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Nano Research 2024年第9期17卷 8112-8118页

作者： zi-Jun Zou Shi-Yi Yin Yao Tang Sheng-liang Zhong Lei Wang Shi-Long Xu Hai-Wei liang College of Chemistry and Chemical Engineering Jiangxi Normal UniversityNanchang 330022China Department of Chemistry University of Science and Technology of ChinaHefei 230026China School of Materials and Chemical Engineering Anhui Jianzhu UniversityHefei 230601China

Carbon-supported platinum-lanthanum(Pt-Ln)intermetallic compound(IMC)nanoparticles with high activity and robust stability have been demonstrated as promising cathode catalysts for proton-exchange membrane fuel ***,the preparation of Pt-Ln IMC catalysts needs high-temperature annealing treatment that inevitably causes nanoparticle sintering,resulting in significant reduction of the electrochemical surface area and mass-based ***,we prepare small-sized M-doped Pt_(5)Ce(M=Ga,Cd,and Sb)IMCs catalysts via a low-melting-point metal doping *** speculate that the doping of low-melting-point metals can facilitate the generation of vacancies in the crystal lattice through thermal activation and thus reduce the kinetic barriers for the formation of intermetallic Pt_(5)Ce *** prepared Ga-doped Pt_(5)Ce catalyst exhibits a higher electrochemical active surface area(81 m^(2)·gPt^(-1))and a larger mass activity(0.45 A·mgPt^(-1)at 0.9 V)over the undoped Pt_(5)Ce and commercial Pt/C *** the membrane electrode assembly test,the Ga-doped Pt_(5)Ce cathode delivers a power density of 0.98 W·cm^(-2)at 0.67 V,along with a voltage loss of only 27 mV at 0.8 A·cm^(-2)at the end of accelerated stability test.

关键词： P5Ce low-melting-point metal small-sized intermetallic compound catalysis fuel cells