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Etching Mechanism of Ti_(3)C_(2)Cl_(2) MXene Phases by CuCl_(2)-Lewis Molten Salt Method

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 863-868页

作者：严明 ZhU Yu hUANG Jiangtao ChEN haoyu DENG Yuxiao ChEN Yanlin 王娟 jan-Michael Albina hubei Provincial Key Laboratory of Green Materials for Light Industry Hubei University of TechnologyWuhan 430068China New Materials and Green Manufacturing Talent Introduction and Innovation Demonstration Base Hubei University of TechnologyWuhan 430068China hubei Longzhong Laboratory Xiangyang 441000China

We described a method for obtaining fluorine-free Ti_(3)C_(2)Cl_(2)MXene phases by melting copper in CuCl_(2)instead of aluminum in Ti_(3)AlC_(2).XRD results show that when molten salt CuCl_(2)etches Ti_(3)AlC_(2),it forms an intermediate product Ti_(3)CuC_(2),and then reacts with Ti_(3)CuC_(2)to obtain Ti_(3)C_(2)Cl_(2).The reaction of Ti_(3)AlC_(2)and CuCl_(2)at a temperature of 800℃for 2 h to obtain Ti_(3)C_(2)Cl_(2)with an optimal lamellar structure is shown in SEM *** pseudopotential plane-wave(PP-PW)method is used to calculate on the electronic *** etching mechanism is investigated by the total energies of each *** chemical reaction of Ti_(3)AlC_(2)and CuCl_(2)will first become Ti_(3)CuC_(2)and Cu,and then become Ti_(3)C_(2)Cl_(2)during the Lewis acid etching process,which are consistent with the experimental results.

关键词： molten salt method CuCl_(2) MXene first-principles calculations etching mechanism

Assessment of the effectiveness of weight-adjusted antibiotic administration,for reduced duration,in surgical prophylaxis of primary hip and knee arthroplasty

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World Journal of Orthopedics 2024年第2期15卷 170-179页

作者： Tosan Okoro Michael Wan Takura Darlington Mukabeta Ella Malev Marketa Gross Claudia Williams Muhammad Manjra jan herman Kuiper John Murnaghan Department of Arthroplasty Robert Jones and Agnes Hunt Orthopaedic Hospital NHS Foundation TrustOswestry SY107AGUnited Kingdom School of Medicine Keele UniversityStaffordshire ST55BGUnited Kingdom St Joseph’s health Centre Unity Health TorontoToronto M6R 1B5Canada Department of Arthroplasty The Royal London HospitalBarts Health NHS TrustLondon E11BBUnited Kingdom Department of Arthroplasty Sunnybrook Holland Orthopaedic and Arthritis CentreToronto M4Y 1H1Canada Institute for Science and Technology in Medicine Keele UniversityStaffordshire ST51BGUnited Kingdom

BACKGROUND Prophylactic antibiotics have significantly led to a reduction in the risk of postoperative surgical site infections(SSI)in orthopaedic *** aim of using antibiotics for this purpose is to achieve serum and tissue drug levels that exceed,for the duration of the operation,the minimum inhibitory concentration of the likely organisms that are *** antibiotics reduce the rate of SSIs in lower limb arthroplasty from between 4%and 8%to between 1%and 3%.Controversy,however,still surrounds the optimal frequency and dosing of antibiotic *** To evaluate the impact of introduction of a weight-adjusted antibiotic prophylaxis regime,combined with a reduction in the duration of administration of post-operative antibiotics on SSI incidence during the 2 years following primary elective total hip and knee arthroplasty METhODS Following ethical approval,patients undergoing primary total hip arthroplasty(ThA)/total knee arthroplasty(TKA)with the old regime(OR)of a preoperative dose[cefazolin 2 g intravenously(IV)],and two subsequent doses(2 h and 8 h),were compared to those after a change to a new regime(NR)of a weight-adjusted preoperative dose(cefazolin 2 g IV for patients120 kg)and a post-operative dose at 2 *** primary outcome in both groups was SSI rates during the 2 years *** A total of n=1273 operations(ThA n=534,TKA n=739)were performed in n=1264 *** was no statistically significant difference in the rate of deep(OR 0.74%(5/675)vs NR 0.50%(3/598);fishers exact test P=0.72),nor superficial SSIs(OR 2.07%(14/675)vs NR 1.50%(9/598);chi-squared test P=0.44)at 2 years *** propensity score weighting and an interrupted time series analysis,there was also no difference in SSI rates between both groups[RR 0.88(95%CI 0.61 to 1.30)P=0.46].CONCLUSION A weight-adjusted regime,with a reduction in number of post-operative doses had no adverse impact on S

关键词： Antibiotics Weight-adjusted hip and knee arthroplasty Surgical site infection

A probe into the acid deposition mitigation path in China over the last four decades and beyond

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National Science Review 2024年第4期11卷 84-92页

作者： Qian Yu Xiaodong Ge haotian Zheng Jia Xing Lei Duan Dongwei Lv Dian Ding Zhaoxin Dong Yisheng Sun Posch Maximilian Danni Xie Yu Zhao Bin Zhao Shuxiao Wang jan Mulder Thorj?rn Larssen Jiming hao State Key Laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua University State Key Laboratory of Pollution Control &Resource Reuse and School of the Environment Nanjing University State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex School of EnvironmentTsinghua University International Institute for Applied System Analysis(IIASA) School of Land Engineering Chang'an University Faculty of Environmental Sciences and Natural Resource Management Norwegian University of Life Sciences Norwegian Institute for Water Research

China currently has the highest acid deposition globally, yet research on its status, impacts, causes and controls is lacking. here, we compiled data and calculated critical loads regarding acid deposition. The results showed that the abatement measures in China have achieved a sharp decline in the emissions of acidifying pollutants and a continuous recovery of precipitation p h, despite the drastic growth in the economy and energy consumption. however, the risk of ecological acidification and eutrophication showed no significant decrease. With similar emission reductions, the decline in areas at risk of acidification in China(7.0%) lags behind those in Europe(20%) or the USA(15%). This was because, unlike Europe and the USA, China's abatement strategies primarily target air quality improvement rather than mitigating ecological impacts. Given that the area with the risk of eutrophication induced by nitrogen deposition remained at 13%of the country even under the scenario of achieving the dual targets of air quality and carbon dioxide mitigation in 2035, we explored an enhanced ammonia abatement pathway. With a further 27% reduction in ammonia by 2035, China could largely eliminate the impacts of acid deposition. This research serves as a valuable reference for China's future acid deposition control and for other nations facing similar challenges.

关键词： acid deposition critical loads acidification eutrophication ammonia abatement

haplotype-based phylogenetic analysis and population genomics uncover the origin and domestication of sweetpotato

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Molecular Plant 2024年第2期17卷 277-296页

作者： Mengxiao Yan Ming Li Yunze Wang Xinyi Wang M-hossein Moeinzadeh Dora G.Quispe-huamanquispe Weijuan Fan Yijie Fang Yuqin Wang haozhen Nie Zhangying Wang Aiko Tanaka Bettina heider jan F.Kreuze Godelieve Gheysen hongxia Wang Martin Vingron Ralph Bock Jun Yang Shanghai Key Laboratory of Plant Functional Genomics and Resources Shanghai Chenshan Botanical GardenShanghai 201602China College of Life Sciences Chongqing Normal UniversityChongqing 401331China Biotechnology and Nuclear Technology Research Institute Sichuan Academy of Agricultural SciencesChengdu 610061China College of Life Sciences Shanghai Normal UniversityShanghai 200234China Department of Computational Molecular Biology Max Planck Institute for Molecular GeneticsIhnestraBe 63-7314195 BerlinGermany Department of Biotechnology Ghent University9000 GhentBelgium Guangdong Provincial Key Laboratory of Crops Genetics and Improvement Crop Research InstituteGuangdong Academy of Agricultural SciencesGuangzhou 510640China Graduate School of Bioagricultural Sciences Nagoya UniversityChikusaNagoya 464-8601Japan international Potato Center(CIP) LimaPeru CAS Center for Excellence of Molecular Plant Sciences Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200233China Max-Planck-Institut fur Molekulare Pflanzenphysiologie Am Muhlenberg 114476 Potsdam-GolmGermany

The hexaploid sweetpotato(lpomoea batatas)is one of the most important root crops ***,its genetic origin remains controversial,and its domestication history remains *** this study,we used a range of genetic evidence and a newly developed haplotype-based phylogenetic analysis to identify two probable progenitors of *** diploid progenitor was likely closely related to lpomoea ae-quatoriensis and contributed the B,subgenome,IbT-DNA2,and the lineage 1 type of chloroplast genome to *** tetraploid progenitor of sweetpotato was most likely *** 4x,which donated the B2 subgenome,IbT-DNA1,and the lineage 2 type of chloroplast *** most likely originated from reciprocal crosses between the diploid and tetraploid progenitors,followed by a subsequent whole-genome *** addition,we detected biased gene exchanges between the subgenomes;the rate of B,to B2 subgenome conversions was nearly three times higher than that of B2 to B subgenome *** analyses revealed that genes involved in storage root formation,maintenance of genome stabil-ity,biotic resistance,sugar transport,and potassium uptake were selected during the speciation and domestication of *** study sheds light on the evolution of sweetpotato and paves the way forimprovementofthiscrop.

关键词： sweetpotato origin gene conversion domestication IbT-DNA hPA

On p-convergent Operators on Banach Lattices

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Acta Mathematica Sinica,English Series 2018年第5期34卷 873-890页

作者： Elroy D.ZEEKOEI jan h.FOURIE Unit for Business Mathematics and Informatics North-West University (NWU)

The notion of a p-convergent operator on a Banach space was originally introduced in 1993 by Castillo and SAnehez in the paper entitled ＂Dunford-Pettis-like properties of continuous vector function spaces＂. In the present paper we consider the p-convergent operators on Banach lattices, prove some domination properties of the same and consider their applications （together with the notion of a weak p-convergent operator, which we introduce in the present paper） to a study of the Schur property of order p. Also, the notion of a disjoint p-convergent operator on Banach lattices is introduced, studied and its applications to a study of the positive Schur property of order p are considered.

关键词： p-convergent operator disjoint p-convergent operator weak p-convergent operator Schur property of order p positive Schur property of order p

The role of zonal flows in reactive fluid closures

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Plasma Science and Technology 2018年第7期20卷 41-49页

作者： jan weiland Chalmers University of Technology and EURATOM-VR Association SE-41296 GothenburgSweden

We will give an overview of results obtained by our reactive fluid model. It is characterised as a fluid model where all moments with sources in the experiment are kept. Furthermore, full account is taken for the highest moments appearing in unexpanded denominators also including full toroidicity. It has been demonstrated that the strength of zonal flows is dramatically larger in reactive fluid closures than in those which involve dissipation. This gives a direct connection between the fluid closure and the level of excitation of turbulence. This is because zonal flows are needed to absorb the inverse cascade in quasi 2D turbulence. This also explains the similarity in structure of the transport coefficients in our model with a reactive closure in the energy equation and models which have a reactive closure because of zero ion temperature such as the hasegawa-Wakatani model. Our exact reactive closure unifies several well-known features of tokamak experiments such as the L-h transition, internal transport barriers and the nonlinear Dimits upshift of the critical gradient for onset of transport. It also gives transport of the same level as that in nonlinear gyrokinetic codes. Since these include the kinetic resonance this confirms the validity of the thermodynamic properties of our model. Furthermore, we can show that while a strongly nonlinear model is needed in kinetic theory a quasilinear model is sufficient in the fluid description. Thus our quasilinear fluid model will be adequate for treating all relevant problems in bulk transport. This is finally confirmed by the reproduction by the model of the experimental power scaling of the confinement time Te ~ P-2/3. This confirms the validity of our reactive fluid model. This also gives credibility to our ITER simulations including the h-mode barrier. A new result is here, that alpha heating strongly reduces the slope of the h-mode barrier. This should significantly reduce the effects of ELM＇s.

关键词： turbulent transport improved mixing length estimates zonal flows toroidicity

Impact of surface phase coexistence on the development of step-free areas on Si（111）

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Frontiers of Materials Science 2015年第2期9卷 141-146页

作者： Andreas FISSEL Ayan Roy ChAUDhURI jan KRUGENER Philipp GRIBISCh h. Jorg OSTEN Institute of Electronic Materials and Devices Leibniz University Hannover Schneiderberg 32 30167 Hannover Germany

The step-flow growth condition of Si on Si（111） near the （7×7）-＂1×1＂ surface phase transition temperature Tc are analyzed within the framework of Burton- Cabrera-Frank theory. In particular, coexistence of both surface phases well below Tc and their specific influence on the step-flow growth behavior are considered. We presume that under dynamical condition of growth, the surface initially covered by only the （7×7） phase separates into domains surrounded by ＂1×1＂ areas. On such a surface, the overall supersaturation should be reduced drastically compared to a surface with only （7×7）, resulting in much larger critical terrace width for nucleation.

关键词： molecular beam epitaxy step-flow growth mode surface superstructure silicon

A Population Balance Model for Disperse Systems:Particle Size Distribution in Suspension Polymerization

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Chinese Journal of Chemical Engineering 1999年第4期7卷 332-344页

作者：陈中 Werner Pauer h.-U.Moritz jan Prss hans-Joachim Warnecke Chemical Engineering University of PaderbornPaderborn 33098Germany

On the basis of population balance a mathematical model is developed to describe the formation of polymer particle in styrene suspension polymerization. The characteristics of coalescence and breakage of droplets and the gel effect are analyzed in particular. Parameters of the models are estimated by experimental data on reaction conversion and particle size distribution. The results show that the model is suitable for predicting polymerization processes.

关键词： population balance model styrene suspension polymerization particle size distribution

A detailed mechanism of degradation behaviour of biodegradable as-ECAPed Zn-0.8Mg-0.2Sr with emphasis on localized corrosion attack

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Bioactive Materials 2023年第9期27卷 447-460页

作者： jan Pinc Andrea Skolakova Vojtech hybasek Sarka Msallamova Petr Vertat Petr Ashcheulov Martin Vondracek jan Duchon Ingrid McCarroll Matej hývl Swarnendu Banerjee jan Drahokoupil Jirí Kubasek Dalibor Vojtech Jaroslav Capek Institute of Physics of the Czech Academy of Sciences Na Slovance 1999/2Prague 818221Czech Republic University of Chemistry and Technology Faculty of Chemical TechnologyDepartment of Metals and Corrosion EngineeringTechnicka 516628Praha 6-DejviceCzech Republic Max-Planck-Institut Für Eisenforschung Max-Planck-Straße 140237DüsseldorfGermany

In this study, advanced techniques such as atom probe tomography, atomic force microscopy, X-ray photoelectron spectroscopy, and electrochemical impedance spectroscopy were used to determine the corrosion mechanism of the as-ECAPed Zn-0.8Mg-0.2Sr alloy. The influence of microstructural and surface features on the corrosion mechanism was investigated. Despite its significance, the surface composition before exposure is often neglected by the scientific community. The analyses revealed the formation of thin ZnO, MgO, and MgCO3 layers on the surface of the material before exposure. These layers participated in the formation of corrosion products, leading to the predominant occurrence of hydrozincite. In addition, the layers possessed different resistance to the environment, resulting in localized corrosion attacks. The segregation of Mg on the Zn grain boundaries with lower potential compared with the Zn-matrix was revealed by atom probe tomography and atomic force microscopy. The degradation process was initiated by the activity of micro-galvanic cells, specifically Zn - Mg2Zn11/SrZn13. This process led to the activity of the crevice corrosion mechanism and subsequent attack to a depth of 250 μm. The corrosion rate of the alloy determined by the weight loss method was 0.36 mm⋅a􀀀 1. Based on this detailed study, the degradation mechanism of the Zn-0.8Mg-0.2Sr alloy is proposed.

关键词： Biodegradable metals Zinc-based alloy Characterization Mechanism ECAP