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Hydroformylation of formaldehyde to glycolaldehyde:An alternative synthetic route for ethylene glycol

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Chinese Journal of Chemical Engineering 2021年第7期34卷 3-16页

作者： Jie Wei Maoshuai Li Meiyan Wang Shixiang Feng weikang dai Qi Yang Yi Feng Wanxin Yang Cheng Yang Xinbin Ma Key Laboratory for Green Chemical Technology of Ministry of Education Collaborative Innovation Center of Chemical Science and EngineeringSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China

Hydroformylation of formaldehyde to glycolaldehyde(GA),as a vital reaction in both direct and indirect process of syngas to ethylene glycol(EG),shows great advantages in the aspects of the process complexity and clean *** hydroformylation of formaldehyde to GA is thermodynamically unfavourable,requiring the development of highly efficient hydroformylation catalytic systems,appropriate reaction conditions and in-depth understanding of the reaction *** this review,we have made a detailed summary on the reaction in terms of the reaction network,thermodynamics,metal complex catalysts(including central metals and ligands),reaction conditions(e.g.,temperature,pressure,formaldehyde source and solvent)and ***,the reaction mechanisms,involving neutral and anionic complex in the catalytic cycle,have been summarized and followed by a discussion on the impact of the crucial intermediates on the reaction pathways and product distribution.A brief overview of product separation and catalyst recovery has been presented in the final *** review gives new insights into the factors that impact on the formaldehyde hydroformylation and reaction mechanisms,which helps to design more efficient catalytic systems and reaction processes for EG production via the hydroformylation route.

关键词： Formaldehyde Syngas Hydroformylation Glycolaldehyde Ethylene glycol Mechanism

Enhanced selective hydrogenation of glycolaldehyde to ethylene glycol over Cu^(0)-Cu^(+)sites

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Chinese Journal of Chemical Engineering 2023年第5期57卷 141-150页

作者： Qi Yang weikang dai Maoshuai Li Jie Wei Yi Feng Cheng Yang Wanxin Yang Ying Zheng Jie Ding Mei-Yan Wang Xinbin Ma Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Selective hydrogenation of hydroxyaldehydes to polyalcohols is challenging due to the competitive hydrogenation of C=O and *** study develops heterogeneous Cu catalysts for the selective synthesis of ethylene glycol via batch liquid-phase hydrogenation of ***_(2)supported Cu,fabricated by ammonia evaporation,enables to catalyze the C=O bond hydrogenation with retaining the CAO bond intact,yielding higher selective hydrogenation activity with ethylene glycol selectivity up to 99.8%relative to MgO,Al_(2)O_(3),CeO_(2),and TiO_(2)supports and Cu/SiO_(2)synthesized by deposition–precipitation and *** confirm that highly efficient 20Cu/SiO_(2)-AE-623 K catalyst fabricated by ammonia evaporation is featured with larger Cu^(0)and Cu^(+)surface areas,of which the Cu^(+)species created from reducing copper phyllosilicate exhibit higher reactivity.A synergistic effect between Cu^(+)and Cu^(0)facilitates the selective adsorption/activation of glycolaldehyde on Cu^(+)sites and the dissociation of H_(2)on Cu^(0)sites,bringing a remarkable improvement in the selective hydrogenation performance.

关键词： Hydrogenation Multiphase reaction Biomass Copper phyllosilicate Ammonia evaporation

Organo-electroreduction enables arylcarboxylation of styrenes

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Science China Chemistry 2024年第11期67卷 3825-3832页

作者： Yanwei Wang Qian Wang Zile Zhu weikang Qi Youai Qiu State Key Laboratory and Institute of Elemento-Organic Chemistry Frontiers Science Center for New Organic Matter Haihe Laboratory of Sustainable Chemical Transformations College of Chemistry Nankai University

Electroreduction offers an alternative to generate high active intermediates from electrophiles(halides, alkenes, etc.) in organic synthesis. However, it still remains challenge to enable the transformations in controlled fashion for substrates with similar reduction potentials. Herein, an electroreductive arylcarboxylation of styrenes with aryl halides and CO2promoted by an organomediator has been developed. The reaction exhibits the remarkable reactivity control between styrenes and aryl halides bearing very similar reduction potentials, which is enabled by the addition of a simple organic mediator. The mediated process for different kinds of aryl halides(iodides and bromides) could be achieved by simply tuning the electronic effect of the skeleton of naphthalene. This protocol displays a broad substrate scope and the extension to late-stage modification of biorelevant molecules and their derivatives showed a bright prospect. Moreover, density functional theory(DFT) calculations and mechanistic studies have been conducted and provide solid support to rationalize the selectivity and reactivity control observed.

关键词： CO2 utilization reductive organo-mediator carboxylation electroreduction aryl halides

Tetrathiafulvalene esters with high redox potentials and improved solubilities for non-aqueous redox flow battery applications

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Green Energy & Environment 2024年第5期9卷 899-908页

作者： weikang Hu Jiaqi Xu Nanjie Chen Zongcai Deng Yuekun Lai Dongyang Chen College of Materials Science and Engineering Fuzhou UniversityFuzhou350116China College of Chemical Engineering Fuzhou UniversityFuzhou350116China

The exploitation of high performance redox-active substances is critically important for the development of non-aqueous redoxﬂow ***,three tetrathiofulvalene(TTF)derivatives with different substitution groups,namely TTF diethyl ester(TTFDE),TTF tetramethyl ester(TTFTM),and TTF tetraethyl ester(TTFTE),are prepared and their energy storage properties are *** has been found that the redox potential and solubility of these TTF derivatives in conventional carbonate electrolytes increases with the number of ester *** battery with a catholyte of 0.2 mol L^(-1) of TTFTE delivers a speciﬁc capacity of more than 10 Ah L^(-1) at the current density of 0.5 C with two discharge voltage platforms locating at as high as 3.85 and 3.60 V ***/Liþ.Its capacity retention can be improved from 2.34 Ah L^(-1) to 3.60 Ah L^(-1) after 100 cycles by the use of an anion exchange membrane to block the crossover of TTF *** excellent cycling stability of the TIF esters is supported by their well-delocalized electrons,as revealed by the density function theory ***,the introduction of more and larger electron-withdrawing groups is a promising strategy to simultaneously increase the redox-potential and solubility of redox-active ma-terials for non-aqueous redoxﬂow batteries.

关键词： Non-aqueous redox flow batteries Tetrathiofulvarene Redox potential Solubility Substituent effect

Synergism of preintercalated manganese ions and lattice water in vanadium oxide cathodes for high-capacity and long-life Zn-ion batteries

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Journal of Energy Chemistry 2024年第9期96卷 709-717页

作者： Mengjing Wu Rongrong Li Kai Yang Lijiang Yin weikang Hu Xiong Pu Key Laboratory of the Ministry of Education for Advanced Catalysis Material Institute of Physical ChemistryCollege of Chemistry and Materials ScienceZhejiang Normal UniversityJinhua 321004ZhejiangChina CAS Center for Excellence in Nanoscience Beijing Key Laboratory of Micro-nano Energy and SensorBeijing Institute of Nanoenergy and NanosystemsChinese Academy of SciencesBeijing 101400China School of Nanoscience and Engineering University of Chinese Academy of SciencesBeijing 100049China Chilwee Power Co.Ltd. Changxing 313100ZhejiangChina

Aqueous Zn-ion batteries(AZIBs)are recognized as a promising energy storage system with intrinsic safety and low cost,but its applications still rely on the design of high-capacity and stable-cycling cathode *** this work,we present an intercalation mechanism-based cathode materials for AZIB,*** vanadium oxide with pre-intercalated manganese ions and lattice water(noted as MVOH).The synergistic effect between Mn^(2+)and lattice H_(2)O not only expands the interlayer spacing,but also significantly enhances the structural *** in-situ and ex-situ characterizations clarify the Zn^(2+)/H^(+)co–(de)intercalation mechanism of MVOH in aqueous *** demonstrated remarkable structure stability,excellent kinetic behaviors and ion-storage mechanism together enable the MVOH to demonstrate satisfactory specific capacity of 450 mA h g^(−1)at 0.2 A g^(−1),excellent rate performance of 288.8 mA h g^(−1)at 10 A g^(−1)and long cycle life over 20,000 cycles at 5 A g^(−1).This work provides a practical cathode material,and contributes to the understanding of the ion-intercalation mechanism and structural evolution of the vanadium-based cathode for AZIBs.

关键词： Zn-ion batteries Vanadium oxide Pre-intercalation Lattice water Manganese ion

Féeton(B-L gauge boson)dark matter for the 511-keV gamma-ray excess and the prediction of low-energy neutrino flux

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Chinese Physics C 2024年第8期48卷 76-82页

作者： Jie Sheng Yu Cheng weikang Lin Tsutomu T.Yanagida Tsung-Dao Lee Institute&School of Physics and Astronomy Shanghai Jiao Tong UniversityChina Key Laboratory for Particle Astrophysics and Cosmology(MOE)&Shanghai Key Laboratory for Particle Physics and Cosmology Shanghai Jiao Tong UniversityShanghai 200240China South-Western Institute For Astronomy Research Yunnan UniversityKunming 650500China Kavli IPMU(WPI) UTIASUniversity of TokyoKashiwa277-8583Japan

The féeton is the gauge boson of the U(1)_(B−L) gauge *** the gauge coupling constant is extremely small,the féeton becomes a candidate for dark *** show that its decay to a pair of an electron and a positron explains the observed Galactic 511-keV gamma-ray excess in a consistent *** féeton dark matter decays mainly into pairs neutrino and *** low-energy experiments with improved directional capability will enable capturing these neutrino *** seesaw-motivated parameter space predicts a relatively short féeton lifetime that is comparable to the current cosmological constraint.

关键词： feeton 511-keV gamma-ray excess low-energy neutrino

Three-dimensional structural models,evolution and petroleum geological significances of transtensional faults in the Ziyang area,central Sichuan Basin,SW China

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Petroleum Exploration and Development 2024年第3期51卷 604-620页

作者： TIAN Fanglei GUO Tonglou HE Dengfa GU Zhanyu MENG Xianwu WANG Renfu WANG Ying ZHANG weikang LU Guo School of Energy Resources China University of Geosciences(Beijing)Beijing 100083China Key Laboratory of Marine Reservoir Evolution and Hydrocarbon Enrichment Mechanism Ministry of EducationBeijing 100083China Sinopec Southwest Oil and Gas Company Chengdu 610031China

With drilling and seismic data of Transtensional(strike-slip)Fault System in the Ziyang area of the central Sichuan Basin,SW China plane-section integrated structural interpretation,3-D fault framework model building,fault throw analyzing,and balanced profile restoration,it is pointed out that the transtensional fault system in the Ziyang 3-D seismic survey consists of the northeast-trending F_(I)19 and F_(I)20 fault zones dominated by extensional deformation,as well as 3 sets of northwest-trending en echelon normal faults experienced dextral shear *** them,the F_(I)19 and F_(I)20 fault zones cut through the Neoproterozoic to Lower Triassic Jialingjiang Formation,presenting a 3-D structure of an“S”-shaped *** before Permian and during the Early Triassic,the F_(I)19 and F_(I)20 fault zones underwent at least two periods of structural ***,the 3 sets of northwest-trending en echelon normal faults are composed of small normal faults arranged in pairs,with opposite dip directions and partially left-stepped *** before Permian,they had formed almost,restricting the eastward growth and propagation of the F_(I)19 fault *** F_(I)19 and F_(I)20 fault zones communicate multiple sets of source rocks and reservoirs from deep to shallow,and the timing of fault activity matches well with oil and gas generation *** there were favorable Cambrian-Triassic sedimentary facies and reservoirs developing on the local anticlinal belts of both sides of the F_(I)19 and F_(I)20 fault zones,the major reservoirs in this area are expected to achieve breakthroughs in oil and gas exploration.

关键词： transtensional(strike-slip)fault three-dimensional structural model structural evolution petroleum geological significance Ziyang area Sichuan Basin

Near-field wideband beam training for ELAA with uniform circular array

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Science China(Information Sciences) 2024年第6期67卷 370-383页

作者： Yuhao CHEN Linglong dai Department of Electronic Engineering Tsinghua UniversityBeijing National Research Center for Information Science and Technology (BNRist)

Extremely large-scale antenna array(ELAA) at millimeter wave(mmWave) and Terahertz(THz)band has been considered a key technology for combating high attenuation in high-frequency bands in future6G communications. Uniform circular arrays(UCAs) have attracted much attention because of their ability to provide flat beamforming gain at all angles. To realize efficient beamforming, beam training is widely used to acquire channel state information. However, with a large antenna number, the beam training overhead in ELAA systems becomes overwhelming. Moreover, with a large bandwidth, the beam defocus effect severely degrades beam training accuracy. To address these issues, this paper proposes a frequency-dependent focusing(FDF)-based beam training scheme to realize effective beam training in near-field wideband ELAA systems with UCA. Specifically, we first analyze the FDF property of UCA, where signals at different subcarriers can simultaneously focus on different distances. Then, by exploiting the FDF property to search different distances using different subcarriers simultaneously, we design a hierarchical codebook and propose an FDFbased beam training scheme. To reveal the effectiveness of the proposed scheme, we compare its necessary beam training overhead with that of existing schemes. Finally, the simulation results demonstrate that the proposed scheme can achieve accurate beam training in near-field wideband UCA systems with a low beam training overhead.

关键词： extremely large-scale antenna array (ELAA) uniform circular array (UCA) near-field wideband beam training

Seismic performance evaluation of water supply pipes installed in a full-scale RC frame structure based on a shaking table test

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 163-178页

作者： Wu Houli Guo Endong Wang Jingyi dai Xin dai Chenxi Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake AdministrationHarbin 150080China Key Laboratory of Earthquake Disaster Mitigation Ministry of Emergency ManagementHarbin 150080China

As an important part of nonstructural components,the seismic response of indoor water supply pipes deserves much *** paper presents shaking table test research on water supply pipes installed in a full-scale reinforced concrete(RC)frame *** material pipes and different methods for penetrating the reinforced concrete floors are combined to evaluate the difference in seismic *** response spectra and pipe acceleration amplification factors based on test data are discussed and compared with code provisions.A seismic fragility study of displacement demand is conducted based on numerical *** acceleration response and displacement response of different combinations are *** results show that the combination of different pipe materials and different passing-through methods can cause obvious differences in the seismic response of indoor riser pipes.

关键词： water supply pipe different materials shaking table test amplification factor seismic fragility