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Cu-catalyzed regioselective diborylation of 1,3-enynes for the efficient synthesis of 1,4-diborylated allenes

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Chinese Chemical Letters 2024年第5期35卷 141-144页

作者： Wujun jian Mong-Feng Chiou Yajun Li Hongli Bao Song yang National Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationCenter for R&D of Fine Chemicals of Guizhou UniversityGuiyang 550025China Strait Institute of Flexible Electronics(SIFE Future Technologies)Fujian Normal UniversityFuzhou 350117China Key Laboratory of Coal to Ethylene Glycol and Its Related Technology State Key Laboratory of Structural ChemistryFujian Institute of Research on the Structure of MatterUniversity of Chinese Academy of SciencesFuzhou 350002China

Borylation of 1,3-enynes with bis(boronate)compounds often ends up with the formation of hydroborylated products,leaving the diborylation of 1,3-enynes for the formation of 1,4-diborylated allenes to be ***,a copper-catalyzed chemo-,regio-,and stereo-selective diborylation of 1,3-enynes for the efficient construction of 1,4-diborylated allenes under base-free conditions was reported.A wide range of 1,3-enynes bearing various functional groups can participant in the reaction and afforded the corresponding 1,4-diborylated allenes in good to excellent yields,which was enabled by the protocol of Bpin to BF3K *** borylcopper species was supposed to selectively attack the C-C triple bond of the 1,3-enynes.

关键词： Copper catalysis Regioselective 1,3-Enynes Borylation Allenes

Bi_(2)S_(3) nanofiber bunch for highly efficient CO_(2) electroreduction to formate at low overpotential

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Rare Metals 2024年第7期43卷 3391-3399页

作者： Li Wang Wen-Ke Gui Shan jiang Liang Wang jian-Ping yang State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China Centre for Catalysis and Clean Energy Griffith UniversityGold Coast CampusGold CoastQLD 4222Australia

Electrochemical conversion of CO_(2) into valuable chemicals represents a promising strategy to alleviate the environmental issues caused by excessive CO_(2) levels in the *** this work,Bi_(2)S_(3) with different morphologies have been fabricated via facile hydrothermal method to investigate the CO_(2) electrochemical reduction process.

关键词： process. facile Electrochemical

Effectiveness and safety of tenofovir amibufenamide in chronic hepatitis B patients

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World Journal of Gastroenterology 2024年第26期30卷 3261-3263页

作者： Li-yang Meng Chao-Ting yang jian-Feng Bao Jin-Song Huang The Fourth Clinical Medical College Zhejiang Chinese Medical UniversityHangzhou 310053Zhejiang ProvinceChina Department of Hepatology Hangzhou Xixi HospitalZhejiang University School of MedicineHangzhou 310023Zhejiang ProvinceChina

This letter to the editor relates to the study entitled“Tenofovir amibufenamide vs tenofovir alafenamide for treating chronic hepatitis B:A real-world study”,which was recently published by Peng et *** B virus infection represents a significant health burden worldwide and can lead to cirrhosis and even liver *** antiviral drugs currently used to treat patients with chronic hepatitis B infection still have many side effects,so it is crucial to identify safe and effective drugs to inhibit viral replication.

关键词： Tenofovir amibufenamide Chronic hepatitis B Non-alcoholic fatty liver disease Alanine transaminase normalization Virological response

Artificial neural network-based method for discriminating Compton scattering events in high-purity germaniumγ-ray spectrometer

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Nuclear Science and Techniques 2024年第2期35卷 64-84页

作者： Chun-Di Fan Guo-Qiang Zeng Hao-Wen Deng Lei Yan jian.yang Chuan-Hao Hu Song Qing yang Hou College of Nuclear Technology and Automation Engineering Chengdu University of TechnologyChengdu 610059China

To detect radioactive substances with low activity levels,an anticoincidence detector and a high-purity germanium(HPGe)detector are typically used simultaneously to suppress Compton scattering background,thereby resulting in an extremely low detection limit and improving the measurement ***,the complex and expensive hardware required does not facilitate the application or promotion of this ***,a method is proposed in this study to discriminate the digital waveform of pulse signals output using an HPGe detector,whereby Compton scattering background is suppressed and a low minimum detectable activity(MDA)is achieved without using an expensive and complex anticoincidence detector and *** electric-field-strength and energy-deposition distributions of the detector are simulated to determine the relationship between pulse shape and energy-deposition location,as well as the characteristics of energy-deposition distributions for fulland partial-energy deposition *** relationship is used to develop a pulse-shape-discrimination algorithm based on an artificial neural network for pulse-feature *** accurately determine the relationship between the deposited energy of gamma(γ)rays in the detector and the deposition location,we extract four shape parameters from the pulse signals output by the *** learning is used to input the four shape parameters into the ***,the pulse signals are identified and classified to discriminate between partial-and full-energy deposition *** partial-energy deposition events are removed to suppress Compton *** proposed method effectively decreases the MDA of an HPGeγ-energy dispersive *** results show that the Compton suppression factors for energy spectra obtained from measurements on ^(152)Eu,^(137)Cs,and ^(60)Co radioactive sources are 1.13(344 keV),1.11(662 keV),and 1.08(1332 keV),respectively,and that the corresponding MDAs are 1.4%,5.

关键词： High-purity germaniumγ-ray spectrometer Pulse-shape discrimination Compton scattering Artificial neural network Minimum detectable activity

Current status and challenges in the application of microbial PHA particles

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Particuology 2024年第4期87卷 286-302页

作者： Jiaxuan Liu Ziqi Zhou Haoru Li Xinyu yang Zeyu Wang jian Xiao Dai-Xu Wei Key Laboratory of Resource Biology and Biotechnology in Western China Ministry of EducationSchool of MedicineDepartment of Life Sciences and MedicineNorthwest UniversityXi'an710069China School of Clinical Medicine Qujing Medical CollegeQujing655000China School of Physics and Electronic Information Shangrao Normal UniversityShangrao334001China Zigong Affiliated Hospital of Southwest Medical University Zigong Psychiatric Research CenterZigong Institute of Brain ScienceZigong643002China

Polyhydroxyalkanoates(PHAs)are diversiform biopolyesters with a similar structure and different side chain groups,synthesized by a variety of *** to their excellent biodegradability and biocompatibility,PHAs have been used for many applications,including medical implants,antibacterial agents and ***-architecture is an emerging area for the use of *** review summarizes the current status and challenges of PHAs-based particles on the micro-and nano-scale,including their production,degradation,biological safety,and surface *** also focus on the applications of PHA particles in drug delivery systems,environment protection,tissue engi-neering,vaccine engineering,food science,biotechnology and ***,the future development trends of PHAs-based particles are prospected.

关键词： Polyhydroxyalkanoates(PHAs) Particles Synthetic biology Tissue engineering

Research on the solid particle erosion wear of pipe steel for hydraulic fracturing based on experiments and numerical simulations

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Petroleum Science 2024年第4期21卷 2779-2792页

作者： Si-Qi yang jian-Chun Fan Ming-Tao Liu De-Ning Li Jun-Liang Li Li-Hong Han jian-Jun Wang Shang-Yu yang Si-Wei Dai Lai-Bin Zhang State Key Laboratory of Oil and Gas Equipment CNPC Tubular Goods Research Institute Key Laboratory of Oil and Gas Safety and Emergency Technology China University of Petroleum Oil Production Technology Research Institute of Liaohe Oilfield Company Tianjin Gas Storage Branch PetroChina Dagang Oilfield Company Petroleum Production Engineering Research Institute Daqing Oilfield Company

Erosion wear is a common failure mode in the oil and gas industry. In the hydraulic fracturing, the fracturing pipes are not only in high-pressure working environment, but also suffer from the impact of the high-speed solid particles in the fracturing fluid. Beneath such complex conditions, the vulnerable components of the pipe system are prone to perforation or even burst accidents, which has become one of the most serious risks at the fracturing site. Unfortunately, it is not yet fully understood the erosion mechanism of pipe steel for hydraulic fracturing. Therefore, this article provides a detailed analysis of the erosion behavior of fracturing pipes under complex working conditions based on experiments and numerical simulations. Firstly, we conducted erosion experiments on AISI 4135 steel for fracturing pipes to investigate the erosion characteristics of the material. The effects of impact angle, flow velocity and applied stress on erosion wear were comprehensively considered. Then a particle impact dynamic model of erosion wear was developed based on the experimental parameters, and the evolution process of particle erosion under different impact angles, impact velocities and applied stress was analyzed. By combining the erosion characteristics, the micro-structure of the eroded area, and the micro-mechanics of erosion damage, the erosion mechanism of pipe steel under fracturing conditions was studied in detail for the first time. Under high-pressure operating conditions, it was demonstrated through experiments and numerical simulations that the size of the micro-defects in the eroded area increased as the applied stress increased, resulting in more severe erosion wear of fracturing pipes.

关键词： Erosion wear Applied stress Particle impact dynamics Erosion mechanism

The influence of yttrium and manganese additions on the degradation and biocompatibility of magnesium-zinc-based alloys:In vitro and in vivo studies

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Journal of Magnesium and Alloys 2024年第2期12卷 608-624页

作者： Lei Shi yang Yan Chun-sheng Shao Kun Yu Bo Zhang Liang-jian Chen Third Xiangya Hospital Central South UniversityChangsha 410013China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China School of Materials Science and Engineering Central South UniversityChangsha 410083China Department of Mechanical Engineering City University of Hong KongHong KongChina

The repair and regeneration of bone defects are highly challenging orthopedic ***,Mg-based implants have gained popularity due to their unique biodegradation and elastic modulus similar to that of human *** aim of our study is to develop a magnesium alloy with a controllable degradation that can closely match bone tissue to help injuries heal in vivo and avoid cytotoxicity caused by a sudden increase in ion *** this study,we prepared and modified Mg-3Zn,Mg-3Zn-1Y,and Mg-2Zn-1Mn by hot extrusion,and used Mg-2.5Y-2.5Nd was as a *** then investigated the effect of additions of Y and Mn on alloys'*** results show that Mn and Y can improve not only compression strength but also corrosion *** alloy Mg-2Zn-1Mn demonstrated good cytocompatibility in vitro,and for this reason we selected it for implantation in *** degraded Mg-2Zn-1Mn implanted a bone defect area did not cause obvious rejection and inflammatory reaction,and the degradation products left no signs of damage to the heart,liver,kidney,or ***,we find that Mg-2Zn-1Mn can promote an osteoinductive response in vivo and the formation of bone regeneration.

关键词： Magnesium alloy Biodegradation Biocompatibility Bone regeneration Bone defect repair

Mineralogical properties and co-sintering characteristics of fluxed iron ore with magnetite concentrates

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Journal of Iron and Steel Research International 2024年第2期31卷 318-328页

作者： Le-le Niu Zheng-jian Liu jian-liang Zhang Yao-zu Wang Zhen-xing yang Si-da Li Chang-dong Shan Ben Feng School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Institute of Artificial Intelligence University of Science and Technology BeijingBeijing100083China Xinxing Casting Pipe Xinjiang Co. Bayingol841300XinjiangChina

To investigate the feasibility of co-sintering of fluxed iron ore with magnetite concentrates, the mineralogical properties of a novel fluxed iron ore were studied using particle size analysis, microscopic morphology characterization, and X-ray diffraction Rietveld analysis. Following that, the experiments for granulation performance and basic sintering characteristics were designed under seven different fluxed iron ore ratios, and the integrated ranking of different fluxed iron ore ratios was determined using gray relation analysis. Finally, the results of the industrial trails were combined with the feasibility analysis. Test and experimental results show that the fraction of the fluxed iron ore particles larger than 0.5 mm can account for more than 48%, and the particles have two morphologies: spherical-rough and flaky-smooth. Ca elements are found in the form of calcite (CaCO3) and dolomite (CaMg(CO3)2). The average particle size of granules and powder removal rate can be improved from 2.50 to 3.16 mm and 39.60% to 24.20%, respectively, with the increase in the fluxed iron ore ratio. Furthermore, the fluxed iron ore can improve assimilability and liquid fluidity of magnetite concentrates. In terms of overall granulation performance and sintering characteristics, the fluxed iron ore ratios are graded from best to worst as follows: 12%, 15%, 9%, 18%, 21%, 6% and 3%. The industrial trails show that when the fluxed iron ore ratio is increased, the beneficial effect of the superior sintering characteristics of the fluxed iron ore itself is ideally balanced with the negative effect of the lower amount of additional CaO at 12% ratio, and thus, it is feasible to bring the fluxed iron ore into production at a level of roughly 12%.

关键词： Fluxed iron ore Magnetite concentrate Granulation performance Sintering characteristics Gray relation analysis

Research progress on electronic and active site engineering of cobalt‐based electrocatalysts for oxygen evolution reaction

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Carbon Energy 2024年第8期6卷 134-165页

作者： Chuansheng He Linlin yang Jia Wang Tingting Wang jian Ju Yizhong Lu Wei Chen School of Materials Science and Engineering University of JinanJinanChina Catalonia Energy Research Institute—IREC Sant Adriàde BesòsBarcelonaSpain Department of Electronic and Biomedical Engineering University of BarcelonaBarcelonaSpain Graduate School of Integrated Sciences for Life Hiroshima UniversityHigashi‐HiroshimaHiroshimaJapan Wenzhou Institute University of Chinese Academy of SciencesWenzhouChina Oujiang Lab WenzhouChina School of Chemistry and Pharmaceutical Science Guangxi Normal UniversityGuilinChina

Electrocatalytic water splitting has been identified as a potential candidate for producing clean hydrogen energy with zero carbon ***,the sluggish kinetics of oxygen evolution reaction on the anode side of the watersplitting device significantly hinders its practical ***,the efficiency of oxygen evolution processes depends greatly on the availability of cost‐effective catalysts with high activity and *** recent years,extensive theoretical and experimental studies have demonstrated that cobalt(Co)‐based nanomaterials,especially low‐dimensional Co‐based nanomaterials with a huge specific surface area and abundant unsaturated active sites,have emerged as versatile electrocatalysts for oxygen evolution reactions,and thus,great progress has been made in the rational design and synthesis of Co‐based nanomaterials for electrocatalytic oxygen evolution *** the remarkable progress in this area,in this timely review,we highlight the most recent developments in Co‐based nanomaterials relating to their dimensional control,defect regulation(conductivity),electronic structure regulation,and so ***,a brief conclusion about recent progress achieved in oxygen evolution on Co‐based nanomaterials,as well as an outlook on future research challenges,is given.

关键词： Co‐based nanomaterial dimension regulation electronic structure and active site oxygen evolution reaction