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journal of Oceanology and Limnology 2024年第4期42卷 1261-1271页

作者： Yeshao peng Ziao ChEN Qiong DENG Zhen jIA Lingxin KONG peng ZhU Youhou XU Zhicai ShE Guangxi Key Laboratory of Beibu Gulf Marine Biodiversity Conservation Pinglu Canal and Beibu Gulf Coastal Ecosystem Observation and Research Station of GuangxiCollege of Marine SciencesBeibu Gulf UniversityQinzhou 535011China

The chloride channel 7 gene(CLC 7)of the hong Kong oyster Crassostrea hongkongensis was cloned and named ChCLC *** cDNA was 2572 bp in length,with a 5′non-coding region containing 25 bp,a 3′non-coding region containing 327 bp,and an open reading frame of 2298 *** 7 has 96.8%and 92.1%homology with CLC 7 of Crassostrea gigas and Crassostrea virginica,respectively,and it was clustered with CLC 7 of *** and ***-PCR showed that ChCLC 7 was expressed in all eight tissues,with the highest in adductor muscle and second in *** ChCLC 7 expression pattern in gill was altered significantly under high salinity stress with an overall upward and then downward *** RNA interference,the expression of ChCLC 7 and survival rate of oyster under high salinity stress was reduced significantly,and so did the concentration of hemolymph chloride ion in 48-96 h after RNA *** believed that ChCLC 7 could play an important role in osmoregulation of *** by regulating Cl^(-)*** study provided data for the analysis of molecular mechanism against oyster salinity stress.

关键词： Crassostrea hongkongensis chloride channel 7 salinity stress RNA interference

A new insight into LPSO phase transformation and mechanical properties uniformity of large-scale Mg-Gd-Y-Zn-Zr alloy prepared by multi-pass friction stir processing

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journal of Magnesium and Alloys 2024年第5期12卷 2041-2056页

作者： Xiaohu Guan Wen Wang Ting Zhang Pai peng Qiang Liu peng han Ke Qiao jun Cai Liqiang Wang Kuaishe Wang School of Metallurgical Engineering National and Local Joint Engineering Research Center for Functional Materials ProcessingXi’an University of Architecture and TechnologyNo.13 Yanta RoadXi’anShaanxi 710055China Xi’an Rare Metal Materials Institute Co.Ltd Xi’an 710016China State Key Laboratory of Metal Matrix Composites School of Material Science and EngineeringShanghai Jiao Tong UniversityNo.800 Dongchuan RoadShanghai 200240China

A large-scale fine-grained Mg-Gd-Y-Zn-Zr alloy plate with high strength and ductility was successfully prepared by multi-pass friction stir processing(MFSP)technology in this *** structure of grains and long period stacking ordered(LPSO)phase were characterized,and the mechanical properties uniformity was ***,a quantitative relationship between the microstructure and tensile yield strength was *** results showed that the grains in the processed zone(PZ)and interfacial zone(IZ)were refined from 50μm to 3μm and 4μm,respectively,and numerous original LPSO phases were *** IZ,some block-shaped 18R LPSO phases were transformed into needle-like 14h LPSO phases due to stacking faults and the short-range diffusion of solute *** severe shear deformation in the form of kinetic energy caused profuse stacking fault to be generated and move rapidly,greatly increasing the transformation rate of LPSO *** MFSP,the ultimate tensile strength,yield strength and elongation to failure of the large-scale plate were 367 MPa,305 MPa and 18.0% *** refinement and LPSO phase strengthening were the major strengthening mechanisms for the MFSP *** particularly,the strength of IZ was comparable to that of PZ because the strength contribution of the 14h LPSO phase offsets the lack of grain refinement strengthening in *** result opposes the widely accepted notion that IZ is a weak region in MFSP-prepared large-scale fine-grained plate.

关键词： Friction stir processing Multi-pass Mg-Gd-Y-Zn-Zr alloy LPSO phase transformation Mechanical properties

Improving corrosion resistance of additively manufactured WE43 magnesium alloy by high temperature oxidation for biodegradable applications

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journal of Magnesium and Alloys 2024年第3期12卷 940-953页

作者： jinge Liu Bangzhao Yin Fei Song Bingchuan Liu Bo peng peng Wen Yun Tian Yufeng Zheng Xiaolin Ma Caimei Wang State Key Laboratory of Tribology in Advanced Equipment Beijing100084China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Department of Orthopaedics Beijing Tsinghua Changgung HospitalInstitute for Precision MedicineTsinghua UniversityBeijing102218China Department of Orthopaedics Peking University Third HospitalBeijing 100191China Engineering Research Center of Bone and joint Precision Medicine Ministry of EducationBeijing 100191China School of Materials Science and Engineering Peking UniversityBeijing 100871China Beijing AKEC Medical Co. Ltd.Beijing 102200China

Laser powder bed fusion(L-PBF)has been employed to additively manufacture WE43 magnesium(Mg)alloy biodegradable implants,but WE43 L-PBF samples exhibit excessively rapid *** this work,dense WE43 L-PBF samples were built with the relativity density reaching 99.9%.high temperature oxidation was performed on the L-PBF samples in circulating air via various heating temperatures and holding *** oxidation and diffusion at the elevated temperature generated a gradient structure composed of an oxide layer at the surface,a transition layer in the middle and the *** oxide layer consisted of rare earth(RE)oxides,and became dense and thick with increasing the holding *** matrix was composed ofα-Mg,RE oxides and Mg_(24)RE_(5) *** precipitates almost disappeared in the transition *** passivation effect was observed in the samples treated by a suitable high temperature *** original L-PBF samples lost 40%weight after 3-day immersion in hank’s solution,and broke into fragments after 7-day *** casted and solution treated samples lost roughly half of the weight after 28-day *** high temperature oxidation samples,which were heated at 525℃ for 8 h,kept the structural integrity,and lost only 6.88%weight after 28-day *** substantially improved corrosion resistance was contributed to the gradient structure at the *** one hand,the outmost dense layer of RE oxides isolated the corrosive medium;on the other hand,the transition layer considerably inhibited the corrosion owing to the lack of ***,high temperature oxidation provides an efficient,economic and safe approach to inhibit the corrosion of WE43 L-PBF samples,and has promising prospects for future clinical applications.

关键词： Laser powder bed fusion Biodegradable magnesium alloy high temperature oxidation Corrosion resistance WE43.

Dissociation cross sections ofψ(3770),ψ(4040),ψ(4160),andψ(4415)mesons with nucleons

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Communications in Theoretical Physics 2024年第4期76卷 93-112页

作者： Ruo-Qing Ding Xiao-Ming Xu h j Weber Department of Physics Shanghai UniversityBaoshanShanghai 200444China Department of Physics University of VirginiaCharlottesvilleVA 22904United States of America

We study the dissociation of ψ(3770), ψ(4040), ψ(4160), and ψ(4415) mesons in collision with nucleons, which takes place in high-energy proton-nucleus collisions. The quark interchange between a nucleon and a ■ meson leads to the dissociation of the ■ meson. We consider the reactions:■, and■, where R stands for ψ(3770), ψ(4040), ψ(4160), or ψ(4415). A reaction of a neutron and a ■ meson corresponds to a reaction of a proton and the ■ meson by replacing the up quark with the down quark and vice versa. Transition-amplitude formulas are derived from the S-matrix *** cross sections are calculated with the transition amplitudes for scattering in the prior form and in the post form. The cross sections relate to nodes in the radial wave functions of ψ(3770), ψ(4040), ψ(4160), and ψ(4415) mesons.

关键词： inelastic nucleon-charmonium scattering quark interchange relativistic constituent quark potential model

Stable hydrogen isoscape in precipitation generated using data fusion for East China

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Science China Earth Sciences 2024年第9期67卷 2972-2988页

作者： jiacheng ChEN jie ChEN Xunchang john ZhANG Peiyi peng State Key Laboratory of Water Resources Engineering and Management Wuhan UniversityWuhan 430072China hubei Key Laboratory of Water System Science for Sponge City Construction Wuhan UniversityWuhan 430072China USDA-ARS Oklahoma and Central Plains Agricultural Research Center El Reno OK 73036USA Southwest Research Institute for hydraulic and Water Transport Engineering Chongqing Jiaotong UniversityChongqing 400016China

The stable hydrogen isotope in precipitation is an effective environmental tracer for climatic and hydrologic ***,accurate and high-precision precipitation hydrogen isoscapes are currently unavailable in *** this study,a data fusion method based on Convolutional Neural Networks(CNN)is used to fuse the hydrogen isotopic composition(δ^(2)h_(p))of observations and isotope-equipped general circulation model(iGCM)simulations.A precipitation hydrogen isoscape with a temporal resolution of monthly and a spatial resolution of 50-60 km is established for East China for the 1969-2017 *** to building the isoscape,the performance of three data fusion methods(DFMs)and two bias correction methods(BCMs)is *** results indicate that the CNN fusion method performs the best with a correlation coefficient larger than 0.90 and root mean square error smaller than 10.5‰ when using observation as a *** fusion methods based on back propagation and long short-term memory neural network perform similarly,while slightly outperforming the bias correction ***,the CNN method is used to generate the hydrogen isoscape,and the temporal and spatial distribution characteristics of the hydrogen isotope in precipitation are analyzed based on this *** generated isoscape shows similar spatial and temporal distribution characteristics to *** general,the distribution pattern of δ^(2)h_(p) is consistent with the temperature effect in northern China,and consistent with the precipitation amount effect in southern *** trend of the δ^(2)h_(p) time series is consistent with that of observed precipitation and ***,the generated isoscape effectively reproduces the observations,and has the characteristics of time continuity and relative spatial regularity,which can provide valuable data support for tracking atmospheric and hydrological processes.

关键词： Precipitation Precipitation isotope General circulation model Data fusion Dataset

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Existence of Positive Solutions to a Fractional-Kirchhoff System

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 225-240页

作者： peng-fei Li jun-hui Xie Dan Mu School of Mathematics and Statistics Hubei Minzu UniversityEnshi445000China

LetΩbe a bounded smooth domain in RN(N≥3).Assuming that 00 are constants,we consider the existence results for positive solutions of a class of fractional elliptic system below,{(a+b[u]^(2)_(s))(-Δ)^(s)u=vp+h_(1)(x... 详细信息

LetΩbe a bounded smooth domain in RN(N≥3).Assuming that 0h(p,q)≠(N+2s/N-2s,N+2s/N-2s),and a,b>0 are constants,we consider the existence results for positive solutions of a class of fractional elliptic system below,{(a+b[u]^(2)_(s))(-Δ)^(s)u=vp+h_(1)(x,u,v,▽u,▽v),x∈Ω,(-Δ)^(s)v=u^(q)+h_(2)(x,u,▽,▽u,▽v),x∈Q,u,v>0,x∈Ω,u=v=0,x∈RN\Ω.Under some assumptions of hi(x,u,v,▽u,▽v)(i=1,2),we get a priori bounds of the positive solutions to the problem(1.1)by the blow-up methods and rescaling *** on these estimates and degree theory,we establish the existence of positive solutions to problem(1.1).

关键词： fractional-Kirchhoff system a priori bounds degree theory positive solution

A numerical model study on the spatial and temporal variabilities of dissolved oxygen in Qinzhou Bay of the northern Beibu Gulf

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Acta Oceanologica Sinica 2024年第6期43卷 49-59页

作者： Gaolei Cheng Shiqiu peng Bin Yang Dongliang Lu State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Laboratory for Regional Oceanography and Numerical Modeling Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China Guangxi Key Laboratory of Marine Environmental Change and Disaster in the Beibu Gulf Beibu Gulf UniversityQinzhou 535011China

Oxygen facilitates the breakdown of the organic material to provide energy for *** concentration of dissolved oxygen(DO) in the water must exceed a certain threshold to support the normal metabolism of marine *** in the northern B eibu Gulf,Qinzhou B ay receives abundant freshwater and nutrients from several rivers which significantly influence the level of the dissolved ***,the spatial-temporal variations of DO as well as the associated driving mechanisms have been rarely studied through field *** this study,a three-dimension al coupled physical-biogeochemical model is used to investigate the spatial and seasonal variations of the DO and the associated driving mechanisms in Qinzhou B *** validation against observations indicates that the model can capture the seasonal and inter-annual variability of the DO concentration with the range of 5-10 mg/*** experiments show that the river discharges,winds and tides play crucial roles in the seasonal variability of the DO by changing the vertical mixing and stratification of the water column and the circulation *** winter,the tide and wind forces have strong effects on the DO distribution by enhancing the vertical mixing,especially near the bay *** summer,the river discharges play a dominant role in the DO distribution by inhibiting the vertical water exchange and delivering more nutrients to the Bay,which increases the DO depletion and results in lower DO on the bottom of the estuary salt *** findings can contribute to the preservation and management of the coastal environment in the northern Beibu Gulf.

关键词： river plume dissolved oxygen stratification physical-biological model

Microstructures and mechanical properties of laser-directed energy deposited CrCoNi medium-entropy alloy

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Rare Metals 2024年第7期43卷 3286-3300页

作者： Wen-jie Zhao Chang-Yu Liu peng-Cheng Che Zhi-Liang Ning hong-Bo Fan jian-Fei Sun Yong-jiang huang Alfonso h.W.Ngan National Key Laboratory for Precision hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China Space Environment Simulation Research Infrastructure Harbin Institute of TechnologyHarbin 150001China Department of Mechanical Engineering The University of Hong KongHong Kong 999077China

The distinctive intrinsic heat treatment(IhT)originating from cyclic reheating in the laser-directed energy deposition(LDED) has attracted growing attention in recent *** this investigation,simulations and experimental characterizations were performed to examine the impact of IhT on the micros true ture and mechanical properties of LDED-fabricated CrCoNi medium-entropy alloy(MEA).The results show that the intensity of the IhT is proportional to the utilized laser energy density(LED).As the LED increased,significant dynamic recrystallization and grain refinement occurred within the alloy due to the enhanced intensity of ***,the high LED leads to severe hot cracking within the as-built MEA,resulting in inferior *** decreasing LED,the hot cracking was effectively ***,low LED weakened the intensity of IhT and consequently inhibited kinetic conditions of dynamic recrystallization,resulting in a heterogeneous grain structure characterized by multi-scale-sized *** structure provides significant hetero-deformation-induced hardening during plastic deformation,enabling the alloy to have a sustainable work-hardening *** expect that this work will have implications in taking full advantage of the unique IhT of the LDED process to fabricate ME As with excellent metallurgical quality and mechanical performance.

关键词： Intrinsic heat treatment Laser-directed energy deposition CrCoNi MEA Dynamic recrystallization heterogeneous grain structure

Promoted surface charge density from interlayer Zn–N_(4) configuration in carbon nitride for enhanced CO_(2) photoreduction

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Nano Research 2024年第4期17卷 2400-2409页

作者： Xianjin Shi Yu huang Gangqiang Zhu Wei peng Meijuan Chen State Key Laboratory of Loess and Quaternary Geology(SKLLQG) Key Laboratory of Aerosol Chemistry and PhysicsInstitute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China Center of Excellence in Quaternary Science and Global Change Chinese Academy of SciencesXi’an 710061China University of Chinese Academy of Sciences Beijing 100049China School of Physics and Information Technology Shaanxi Normal UniversityXi’an 710062China School of human Settlements and Civil Engineering Xi’an Jiaotong UniversityXi’an 710049China

The solar-driven reduction of CO_(2) into valuable products is a promising method to alleviate global environmental problems and energy ***,the low surface charge density limits the photocatalytic conversion performance of CO_(2).herein,a polymeric carbon nitride(PCN)photocatalyst with Zn single atoms(Zn1/CN)was designed and synthesized for CO_(2) *** results of the CO_(2) photoreduction studies show that the CO and Ch_(4) yields of Zn1/CN increased fivefold,reaching 76.9 and 22.9μmol/(g·h),respectively,in contrast to the unmodified ***+plasma-etched X-ray photoelectron spectroscopy and synchrotron radiation-based X-ray absorption fine structure results reveal that Zn single atom is mainly present in the interlayer space of PCN in the Zn–N_(4) *** characterizations indicate that the interlayer Zn–N_(4) configuration can amplify light absorption and establish an interlayer charge transfer ***-assisted Kelvin probe force microscopy confirms that more photogenerated electrons are delivered to the catalyst surface through interlayer Zn–N_(4) configuration,which increases its surface charge ***,in-situ infrared spectroscopy combined with density functional theory calculation reveals that promoted surface charge density accelerates key intermediates(*COOh)conversion,thus achieving efficient CO_(2) *** work elucidates the role of internal single atoms in catalytic surface reactions,which provides important implications for the design of single-atom catalysts.

关键词： single-atom catalysts photocatalytic CO_(2)reduction interlayer modification charge transfer dynamics surface charge density

Decreased Nrf2 protein level and low sperm quality in intractable spermatocystitis

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Asian journal of Andrology 2024年第2期26卷 189-194页

作者： Shi-Ze Wang jian-Nan Liu Fen-Fang Zhou Ye-jin-peng Wang peng Zhang Song-Tao Cheng Department of Urology Sichuan Provincial People's HospitalUniversity of Electronic Science and Technology of ChinaChengdu 610072China Department of Urology Zhongnan Hospital of Wuhan UniversityWuhan 430071China Department of health Management and Clinical Medicine School of Medicine and HealthWuhan PolytechnicUniversityWuhan 430071China

To investigate the molecular etiology of low sperm quality in patients with intractable spermatocystitis,spermatozoa samples from patients with persistent hematospermia undergoing transurethral seminal vesiculoscopy and healthy volunteers were *** samples were collected from the seminal vesicles through transurethral seminal vesiculoscopy or by masturbation *** quality was analyzed by a WLjY-9000 color semen analysis *** of tumor necrosis factor alpha(TNFa)and interleukin-6(IL-6)in the seminal plasma was performed using enzyme-linked immunosorbent assay(ELISA).Measurement of h_(2)O_(2)in the seminal plasma was performed with a hydrogen peroxide *** protein levels of nuclear factor erythroid 2-related factor 2(Nrf2)and phosphorylated-Nrf2(p-Nrf2)were measured by western blot analysis and immunofluorescence *** sperm quality parameters and increased levels of inflammatory cytokines(TNFa,IL-6,and h_(2)O_(2))in the seminal plasma were detected among the semen samples from the patients with persistent ***2 and p-Nrf2 were strongly expressed in the nucleus and periphery of human sperm cells,according to the results of the immunofluorescence *** protein levels of Nrf2 and p-Nrf2 were significantly lower in the spermatozoa samples from patients with persistent hematospermia than in those from healthy volunteers with normal sperm *** results suggested that Nrf2 signaling might play a role in the low sperm quality of patients with intractable spermatocystitis.

关键词： h_(2)O_(2) Nrf2 sperm quality spermatocystitis