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Chemical Research in Chinese Universities 2024年第1期40卷 55-63页

作者： WANG Tingting WANG Jia xi Yongjie HU Bin LI Fuwei State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China

Selective activation of C-O bond is of fundamental importance in the precise conversion of oxygenates into value-added compounds in an atom-economic and sustainable manner, and meanwhile, the structurally well-defined dual-atoms catalysts (DACs) have been scarcely investigated in this field. In this study, a series of transition metal DACs anchored on nitrogen-doped graphene (TM2/NC, TM=Pt, Ir, Rh, Pd, Ru, Co, Ni and Cu) was constructed to make a comprehensive investigation of their selectivity in the hydrogenative transformation of furfuryl alcohol (FAL), an important biomass platform molecule, to 1,2-pentanediol (1,2-PeD) via selective cleavage of furanic C5-O bond, by density functional theory (DFT) calculations and microkinetic modeling. We found that Ir2/NC demonstrated a high selectivity for the cleavage of furanic C5-O bond to produce 1,2-PeD, while the production of THFAL or 1,5-pentanediol (1,5-PeD) on other TM2/NC catalysts are more favorable. Furthermore, we found that the selective C-O bond cleavage of FAL furan ring is affected by the orbital overlap between the d-orbitals of the anchored metal atoms and the p-orbitals of the adsorbed C atom in FAL, suggesting that the selectivity of the C-O bond cleavage is inextricably related with the electronic property of the anchored metals.

关键词： Furfuryl alcohol Hydrogenation Dual-atom catalyst Density functional theory(DFT)calculation

High-responsivity on-chip waveguide coupled germanium photodetector for 2 μm waveband

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Photonics Research 2024年第1期12卷 115-122页

作者： JIANING WANG xi WANG YIHANG LI YANFU YANG QINGHAI SONG KE XU Guangdong Provincial Key Laboratory of Semiconductor Optoelectronic Materials and Intelligent Photonic Systems Harbin Institute of TechnologyShenzhen 518055China department of Electronic&Information engineering Harbin Institute of TechnologyShenzhen 518055China department of Science Harbin Institute of TechnologyShenzhen 518055China

Recently,the emerging 2μm waveband has gained increasing interest due to its great potential for a wide scope of *** with the existing optical communication windows at shorter wavelengths,it also offers distinct advantages of lower nonlinear absorption,better fabrication tolerance,and larger free carrier plasma effects for silicon photonics,which has been a proven device *** much progress has been witnessed for silicon photonics at the 2μm waveband,the primary challenge still exists for on-chip *** the maturity and compatibility of the waveguide coupled photodetectors made of germanium,the 2μm regime is far beyond its cutoff *** this work,we demonstrate an efficient and high-speed on-chip waveguidecoupled germanium photodetector operating at the 2μm *** weak sub-bandgap absorption of epitaxial germanium is greatly enhanced by a lateral separation absorption charge multiplication *** detector is fabricated by the standard process offered by a commercial *** device has a benchmark performance with responsivity of 1.05 A/W and 3 dB bandwidth of 7.12 GHz,which is able to receive high-speed signals with up to 20 Gbit/s data *** availability of such an efficient and fast on-chip detector circumvents the barriers between silicon photonic integrated circuits and the potential applications at the 2μm waveband.

关键词： waveguide responsivity wave

Enhancing competency of clinical research nurses:A comprehensive training and evaluation framework

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World Journal of Clinical Cases 2024年第7期12卷 1378-1381页

作者： Yang-xi Liu Yi Xu Tumor Interventional department Taizhou Municipal HospitalTaizhou 318099Zhejiang ProvinceChina

The Sun et al's training program for clinical research nurses(CRNs)in the World Journal of Clinical Cases is a comprehensive and scientific *** includes structured frameworks for CRN training,aiming to improve CRN *** program emphasizes practical abilities,updates training content,and improves evaluation *** cultivation of CRN talents focuses on enhancing the training system,establishing a multifaceted evaluation framework,and continuously refining the training *** feedback and evalua-tion are essential to improve CRNs'competency in practical settings.

关键词： Clinical research nurse Framework Nurse Operations Practice Structure

Recent Advances in Cobalt-Catalyzed Regio-or Stereoselective Hydrofunctionalization of Alkenes and Alkynes

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CCS Chemistry 2024年第5期6卷 1130-1156页

作者： Yan Li xi Lu Yao Fu Hefei National Research Center for Physical Sciences at the Microscale CAS Key Laboratory of Urban Pollutant ConversionAnhui Province Key Laboratory of Biomass Clean EnergyUniversity of Science and Technology of ChinaHefei 230026 Key Laboratory of Precision and Intelligent Chemistry Department of Applied ChemistrySchool of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026

Hydrofunctionalization of alkenes and alkynes is increasingly important in preparing and modifying carbon-centered organic molecules such as pharmaceuticals,agrochemicals,andmaterial *** development of transition-metal-catalysts has revolutionized the hydrofunctionalization of unsaturated hydrocarbons,greatly improving the synthetic efficiency and selectivity of these *** recent years,notable progress has been achieved in low-cost metal-catalyzed alkene and alkyne hydrofunctionalization reactions following the utilization of traditional precious metal catalysts,including palladium,platinum,and ***-abundant cobalt catalysts,which are low in toxicity and exhibit unique reactivity and selectivity,are widely implemented in academic and industrial *** this review,we highlight recent examples of cobalt-catalyzed hydrofunctionalization of alkenes and alkynes to provide an overview of hydrofunctionalization methods,particularly hydroalkylation *** reactions greatly expand the scope and utility of cobalt-catalyzed couplings of carbon—carbon *** also highlight the mechanistic considerations and selective determinants *** hope our discussion will be informative for future developments in cobalt catalysis and hydrofunctionalization reactions.

关键词： hydrofunctionalization cobalt-catalysis alkene alkyne regioselectivity stereoselectivity

Efficient optimization of electron transfer pathway by constructing phosphide/ceria interface boosts seawater hydrogen production

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Journal of Energy Chemistry 2024年第8期95卷 490-498,I0011页

作者： Yifan Zhao Lingfeng Yang Youyu Long Min xi Anran Chen Hua Zhang School of Materials and Energy Yunnan UniversityKunming 650091YunnanChina Electron Microscopy Centre of Yunnan University Yunnan UniversityKunming 650091YunnanChina

Developing efficient and durable hydrogen evolution reaction(HER)electrocatalysts is one of the most important issues for the commercialization of seawater electrolysis,but it remains ***,we report a CeO_(2)-CoP nanoneedle array catalyst loaded on Ti mesh(CeO_(2)-CoP/TM)with workfunction-induced directional charge transport *** CeO_(2)-CoP/TM catalyst showed superior HER catalytic activity and stability,with over potentials of 41 and 60 mV to attain 10 mA cm^(-2),in 1 M KOH and 1 M KOH+seawater electrolyte,*** results and theoretical calculations reveal that the work function drives the charge transfer from CeO_(2)to CoP,which effectively balances the electronic density of CoP and CeO_(2),optimizes the d-band center,and accelerates the water activation kinetics,thus enhancing the HER *** solar-driven water electrolysis device displays a high and stable solar-to-hydrogen conversion efficiency of 19.6%.This study offers a work function-induced directional charge transport strategy to design efficient and durable catalysts for hydrogen production.

关键词： Work function Heterostructure Charge transport Seawater splitting Solar-to-hydrogen

Insights into postural orthostatic tachycardia syndrome after COVID-19 in pediatric patients

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World Journal of Pediatrics 2024年第3期20卷 201-207页

作者： Ya-xi Cui Jun-Bao Du Hong-Fang Jin department of Pediatrics Peking University First HospitalNo.1 Xi-an Men StreetWest DistrictBeijing 100034China State Key Laboratory of Vascular Homeostasis and Remodeling Peking UniversityBeijing 100191China

The pandemic caused by the novel severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)profoundly threatened human health globally and greatly impacted the world economy[1].While most patients recovered,some suff... 详细信息

关键词： acute patients tachycardia

Kuicolong-yu enema decoction retains traditional Chinese medicine enema attenuates inflammatory response ulcerative colitis through TLR4/NF-κB signaling pathway

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World Journal of Gastrointestinal Surgery 2024年第4期16卷 1149-1154页

作者： Li Han Kun Tang xiao-Li Fang Jing-xi Xu xi-Yun Mao Ming Li department of Anorectal Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine Anhui HospitalHefei 230001Anhui ProvinceChina Anorectal Center The First Affiliated Hospital of Anhui University of Traditional Chinese MedicineHefei 230001Anhui ProvinceChina department of Spleen and Stomach Diseases Department of GastroenterologyAffiliated Wuhu Hospital of Traditional Chinese Medicine of Anhui College of Traditional Chinese MedicineWuhu 241000Anhui ProvinceChina

BACKGROUND Ulcer colitis(UC)is a chronic,nonspecific,and noninfectious inflammatory bowel ***,Toll-like receptors(TLRs)have been found to be closely associated with clinical inflammatory *** complete remission in patients with intermittent periods of activity followed by dormancy is ***,no study has explored the mechanism by which Kuicolong-yu enema decoction retains traditional Chinese medicine enemas to attenuate the inflammatory response in *** To explore the mechanism by which Kuicolong-yu enema decoction retains traditional Chinese medicine enemas to attenuate the inflammatory response in *** This prospective clinical study included patients who met the exclusion criteria in 2020 and *** patients with UC were divided into two groups(control and experimental).The peripheral blood of the experimental and control groups were collected under aseptic *** expression of TLR4 protein,NF-κB,IL-6,and IL-17 was detected in the peripheral blood of patients in the experimental group and control group before and 1 month after taking the *** co rrelation analysis was used to analyze the relationship between the expression level of TLR4 protein and the expression levels of downstream signal NF-κB and inflammatory factors IL-6 and IL-17,and P<0.05 was considered statistically *** There were no significant differences in the patient characteristics between the control and experimental *** results showed that the expression levels of TLR4 and NF-κB in the experimental group were significantly lower than those in the control group(P<0.05).The levels of IL-6 and IL-17 in the experimental group were significantly lower than those in the control group(P<0.05).The TLR4 protein expression in the experimental group was positively correlated with the expression level of downstream signal NF-κB and was positively correlated with the levels of downstream inflammatory cytokines IL-6 and IL-

关键词： Ulcerative colitis TLR4 NF-κB signaling pathway Kuicolong-yu enema

Microstructure,wear and friction behavior of CoCrAITaY-xCNTs composite coatings deposited by laser-induction hybrid cladding

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Rare Metals 2024年第4期43卷 1815-1827页

作者： Sheng-Feng Zhou Yu Long Yan-Liang Yi Cheng Deng Lian-xi Hu Institute of Advanced Wear&Corrosion Resistant and Functional Materials Jinan UniversityGuangzhou510632China Wuhan National Laboratory for Optoelectronics(WNLO) Huazhong University of Science and TechnologyWuhan430074China MOE Key Laboratory of New Processing Technology for Non-Ferrous Metals and Materials Guangxi Key Laboratory of Processing for Non-Ferrous Metals and Featured MaterialsGuangxi UniversityNanning530004China School of Mechatronics engineering Guangdong Polytechnic Normal UniversityGuangzhou510635China School of Materials Science and engineering Harbin Institute of TechnologyHarbin150001China

To improve the wear performance of CoCrAlYTa coating,part of the carbon nanotubes(CNTs)chemically reacted with Ta to form reinforcement phase(TaC),while the other CNTs were retained as lubrication ***,the CoCrAlYTa-xCNTs(x=0,1,2,and 4;wt%)composite coatings were prepared by laserinduction hybrid cladding(LIHC),and the microstructure and wear resistance of coatings were systematically *** show that the coatings are mainly composed of TaC,y-(Co,Cr)andβ-(Co,Cr)*** the CNTs content increases from 0 wt%to 4 wt%,the volume fraction of TaC increases from 13.11 vol%to 16.12 vol%.Meanwhile,the nano-hardness ofγ-(Co,Cr)andβ-(Co,Cr)Al are improved from 7.49 and 9.72 to 9.36 and 11.19 GPa,*** a result,the microhardness of coating increases from HV536.25 to HV 738.16,the wear rate decreases from32.4×10^(-3)to 6.1×10^(-3)mg·m^(-1),and the average friction coefficient decreases from 0.55 to *** good wear performance of the coating is attributed to the formation of TaC and the existence of remained CNTs lubricant film.

关键词： Carbon nanotube MCrAlY coating Friction and wear performance Laser-induction hybrid cladding

A unified Minorization-Maximization approach for estimation of general mixture models

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 343-362页

作者： HUANG xi-fen LIU Deng-ge ZHOU Yun-peng ZHU Fei School of Mathematics Yunnan Normal UniversityKunming 650092China department of Statistics and Actuarial Science The University of Hong KongHong KongChina

The mixed distribution model is often used to extract information from heteroge-neous data and perform modeling *** the density function of mixed distribution is complicated or the variable dimension is high,it usually brings challenges to the parameter es-timation of the mixed distribution *** application of MM algorithm can avoid complex expectation calculations,and can also solve the problem of high-dimensional optimization by decomposing the objective *** this paper,MM algorithm is applied to the parameter estimation problem of mixed distribution *** method of assembly and decomposition is used to construct the substitute function with separable parameters,which avoids the problems of complex expectation calculations and the inversion of high-dimensional matrices.

关键词： MM algorithm mixed distribution model parameter estimation assembly decomposition tech-nology parameter separation

Syntheses and properties of associative acrylamide copolymers containing short hydrophobic chains used in a friction reducer for slick-water fracturing

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Petroleum Science 2024年第3期21卷 1889-1901页

作者： Ya-xing Dai xian-Li Zhang Si-Yuan Liu Feng-Run-Ze Zhang Yi-xi Zhang Yu-Tong Sang Jing-xi Zheng Zhao-Sheng Liu Peng Zhang College of Chemistry and Chemical engineering Chongqing University of Science and TechnologyChongqing401331China College of Ecology and Environment Chongqing Resources and Environmental Protection of UniversityChongqing401331China China china Property Project department of Dezhou Mining Property Service CenterShengli Oilfield Company of SinopecDezhou253000ShandongChina

Two allyldimethylalkyl quaternary ammonium salt(AQAS)monomers,N,N-dimethylallylphenylpropylammonium bromide(AQAS1)and N,N-dimethylallylnonylammonium bromide(AQAS2),were synthesized and used to prepare modified polyacrylamide *** new drag reducers were synthesized from acrylamide(AM),sodium acrylate(Na AA)and a cationic modified monomer(AQAS1 or AQAS2)via aqueous solution polymerization,and the copolymers were named P(AM/Na AA/AQAS1)and P(AM/Na AA/AQAS2),*** structures of the drag reduction agents were confirmed by IR and1H NMR *** molecular weight(Mw)of P(AM/Na AA/AQAS1)was 1.79×10^(6)g/*** the copolymer concentration was 1000 mg/L and the flow rate was 45 L/min,in fresh water the highest drag reduction rate was 75.8%,in 10,000 mg/L Na Cl solution the drag reduction rate decreased to 72.9%.The molecular weight of P(AM/Na AA/AQAS2)was 3.17×10^(6)g/*** the copolymer concentration was500 mg/L and the flow rate was 45 L/min,the drag reduction rate reached 75.2%,and in 10,000 mg/L Na Cl solution the drag reduction rate was 73.3%,decreased by approximately 1.9%.The drag reduction rate for partially hydrolyzed polyacrylamide(HPAM)was also investigated,and the results showed that the drag reduction rates for 500 and 1000 mg/L HPAM solutions were merely 43.2%and 49.0%in brine,*** with HPAM,both of the above copolymers presented better drag reduction capacities.

关键词： Shale gas Slick water Drag reducer Modified monomer Copolymerization