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Greatly enhanced corrosion/wear resistances of epoxy coating for Mg alloy through a synergistic effect between functionalized graphene and insulated blocking layer

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journal of Magnesium and Alloys 2024年第1期12卷 332-344页

作者： Z.Y.Xue X.j.Li j.H.Chu M.M.Li D.N.Zou L.b.Tong School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China State Key Laboratory of Advanced Design and Manufacturing for Vehicle body Hunan UniversityChangsha 410082China

The poor corrosion and wear resistances of Mg alloys seriously limit their potential applications in various *** conventional epoxy coating easily forms many intrinsic defects during the solidification process,which cannot provide sufficient *** the current study,we design a double-layer epoxy composite coating on Mg alloy with enhanced anti-corrosion/wear properties,via the spin-assisted assembly *** outer layer is functionalized graphene(FG)in waterborne epoxy resin(WEP)and the inner layer is Ce-based conversion(Ce)*** FG sheets can be homogeneously dispersed within the epoxy matrix to fill the intrinsic defects and improve the barrier *** Ce film connects the outer layer with the substrate,showing the transition *** corrosion rate of Ce/WEP/FG composite coating is 2131 times lower than that of bare Mg alloy,and the wear rate is decreased by~90%.The improved corrosion resistance is attributed to the labyrinth effect(hindering the penetration of corrosive medium)and the obstruction of galvanic coupling *** synergistic effect derived from the FG sheet and blocking layer exhibits great potential in realizing the improvement of multi-functional integration,which will open up a new avenue for the development of novel composite protection coatings of Mg alloys.

关键词： Mg alloy Functionalized graphene Epoxy coating Corrosion/wear resistance blocking layer

Inflow and outflow permeability tests in a very soft clay under low stresses

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journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3270-3283页

作者： j.W.S.Vargas F.A.b.Danziger F.R.Lopes T.Lunne Federal University of Rio de janeiro Rio de JaneiroBrazil Norwegian Geotechnical Institute OsloNorway

In situ inflow and outflow permeability tests with the bAT probe at SarapuíII soft clay test site are presented.A description of the bAT permeability test is provided,discussing its advantages and shortcomings,especially in the case of very soft clays under low *** pressures were monitored during probe installation and were found to be slightly lower than piezocone u2 pore pressures,consistent with the position of the *** role of filter tip saturation was investigated after the usual saturation procedure provided an unsatisfactory pore pressure response during probe *** show that the vacuum saturation procedure provides adequate response during installation and increases the reliability of the coefficient of permeability determination in early *** inflow and outflow tests yielded similar results,indicating that careful execution of the test can lead to good test repeatability regardless of the loading *** sequences of alternated inflow and outflow tests have yielded similar results,indicating that soil reconsolidation and filter clogging were negligible in the tests *** are presented concerning the relationship between index parameters and the in situ coefficient of permeability for SarapuíII clay,which plot outside the range of existing databases.

关键词： Permeability test Soft clay bAT probe Inflow and outflow tests

Revised in-depth meta-analysis on the efficacy of robot-assisted versus traditional free-hand pedicle screw insertion

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Laparoscopic, Endoscopic, and Robotic Surgery 2024年第4期7卷 155-165页

作者： Chumnanvej S. Pillai b.M. Suthakorn j. Neurosurgery Division Department of Surgery Faculty of Medicine Ramathibodi Hospital Mahidol University Bangkok Thailand Department of Anesthesiology and Operating Room Phramongkutklao Hospital Bangkok Thailand Center for biomedical and Robotics Technology (bART LAb) Faculty of Engineering Mahidol University Bangkok Thailand

Objective: Robot-assisted pedicle screw insertion has recently emerged as an alternative to the traditional free-hand technique. However, discrepancies in the accuracy of screw placement between the 2 methods have been highlighted by some comparative studies. This meta-analysis was conducted to synthesize evidence comparing these techniques. Methods: Searches were conducted in 5 electronic databases adhering to specific eligibility criteria for randomized and observational studies. The data were analyzed using RevMan software and the results are presented as odds ratios (ORs), mean differences, or standard mean differences (SMDs) with 95% confidence intervals (CIs). Our analysis included 12 studies (7 randomized trials and 5 observational studies, involving 883 patients and 4903 screws). Results: The results demonstrated a higher rate of Grade A Gertzbein and Robbins pedicle placement score (OR: 1.77; 95% CI: 1.10–2.87), a lower rate of revision surgeries (OR: 0.21; 95% CI: 0.09–0.52), and a shorter radiation exposure duration (SMD = −1.38, 95% CI: −2.32 to −0.44) in the robot-assisted group compared with the free-hand group. Nonetheless, the length of hospital stay, volume of intraoperative blood loss, postoperative visual analogue scale scores for back pain, and rate of wound infection were similar between the 2 groups. Significant heterogeneity was observed in some outcomes. Conclusion: Compared with the free-hand method, the robot-assisted technique provides greater accuracy and reduced radiation exposure. The efficacy of the robot-assisted technique is expected to improve further as experience with its use in surgery grows. © 2024 Zhejiang University

关键词： Fluoroscopy Free-hand Meta-analysis Pedicle screw placement Robotic surgery

Rescattering of stimulated Raman side scattering in nonuniform plasmas

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Matter and Radiation at Extremes 2024年第5期9卷 68-76页

作者： S.Tan Q.Wang Y.Chen W.b.Yao C.Z.Xiao j.F.Myatt School of Physics and Electronics Hunan UniversityChangsha 410082China Institute of Applied Physics and Computational Mathematics Beijing 100094China School of Electrical and Information Engineering Anhui University of Science and TechnologyHuainanAnhui 232001China Department of Electrical and Computer Engineering University of Alberta9211116 St.NWEdmontonAlberta T6G 1H9Canada

Rescattering of stimulated Raman side scattering(SRSS)is observed for the first time via two-dimensional(2D)particle-in-cell(PIC)*** construct a theoretical model for the rescattering process,which can predict the region of occurrence of mth-order SRSS and estimate its *** rescattering process is identified by the 2D PIC simulations under typical conditions of a direct-drive inertial confinement fusion *** electrons produced by second-order SRSS propagate nearly perpendicular to the density gradient and gain nearly the same energy as in first-order SRSS,but there is no cascade acceleration to produce superhot *** studies for a wide range of ignition conditions show that SRSS and associated rescatterings are robust and important processes in inertial confinement fusion.

关键词： nonuniform acceleration scattering

Advancing Evaluation of Microplastics Thresholds to Inform Water Treatment Needs and Risks

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Environment & Health 2024年第7期2卷 441-452页

作者： Omar S.Chowdhury Philip j.Schmidt William b.Anderson Monica b.Emelko Department of Civil and Environmental Engineering University of Waterloo200 University Avenue WestWaterlooON N2L 3G1Canada

Although human health impacts of microplastics are not well understood,concern regarding chemical contaminants retained on or within them is *** water providers are increasingly asked about these risks,but strategies for evaluating them and the extent of treatment needed to manage them are currently *** can potentially induce health effects if the concentration of contaminants adsorbed to them exceeds predetermined drinking water guidelines(e.g.,Maximum Contaminant Levels).The risk posed by microplastics due to adsorbed contaminants is difficult to determine,but a worst-case scenario can be evaluated by using adsorption ***,a“Threshold Microplastics Concentration”(TMC)framework is developed to evaluate whether waterborne microplastic concentrations can potentially result in the intake of regulated contaminants on/in microplastics at levels of human health concern and identify treatment targets for managing associated health *** the TMC does not indicate an immediate health risk;it informs the need for detailed risk assessment or further treatment evaluation to ensure particle removal targets are ***,the TMC concept and framework provide an updateable,science-based screening tool to determine if there is a need for detailed risk assessment or treatment modification due to waterborne microplastics in supplies used for potable water production.

关键词： drinking water treatment chemical contaminants adsorption capacity risk management maximum contaminant level

NONLINEAR FREE SURFACE ACTION WITH AN ARRAY OF VERTICAL CYLINDERS

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Acta Mechanica Sinica 2004年第3期20卷 247-262页

作者： HUANG j.b. Department of Engineering Science University of OxfordUK

Nonlinear diffraction of regular waves by an array of bottom-seated circular cylindersis investigated in frequency domain,based on a Stokes expansion approach.A complete semi-analyticalsolution is developed which allows an efficient evaluation of the second-order potentials in the entirefluid domain,and the wave forces on the *** are derived for the second-orderpotential in the vicinity of individual *** expressions have a simple form,thus providingan effective means for investigating the wave enhancement due to nonlinear interactions with *** on the present method,the wave run-up and free-surface elevations around an arrayof two,three and four cylinders are investigated numerically.

关键词： nonlinear wave diffraction water waves frequency analysis semi-analytical method

Efficient User Identity Linkage based on Aligned Multimodal Features and Temporal Correlation

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Computers, Materials and Continua 2024年第1期81卷 251-270页

作者： Gao j. Zheng K. Wang X. Wu C. Wu b. School of Cyberspace Security Beijing University of Posts and Telecommunications Beijing 100876 China Faculty of Information Technology Beijing University of Technology Beijing 100124 China

User identity linkage (UIL) refers to identifying user accounts belonging to the same identity across different social media platforms. Most of the current research is based on text analysis, which fails to fully explore the rich image resources generated by users, and the existing attempts touch on the multimodal domain, but still face the challenge of semantic differences between text and images. Given this, we investigate the UIL task across different social media platforms based on multimodal user-generated contents (UGCs). We innovatively introduce the efficient user identity linkage via aligned multi-modal features and temporal correlation (EUIL) approach. The method first generates captions for user-posted images with the bLIP model, alleviating the problem of missing textual information. Subsequently, we extract aligned text and image features with the CLIP model, which closely aligns the two modalities and significantly reduces the semantic gap. Accordingly, we construct a set of adapter modules to integrate the multimodal features. Furthermore, we design a temporal weight assignment mechanism to incorporate the temporal dimension of user behavior. We evaluate the proposed scheme on the real-world social dataset TWIN, and the results show that our method reaches 86.39% accuracy, which demonstrates the excellence in handling multimodal data, and provides strong algorithmic support for UIL. © 2024 The Authors. Published by Tech Science Press.

关键词： attention mechanism multimodal models temporal correlation User identity linkage

A comparison of laparoscopic to open pancreaticoduodenectomy for pancreatic adenocarcinoma by propensity score matching analysis

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Laparoscopic, Endoscopic, and Robotic Surgery 2024年第4期7卷 141-146页

作者： Mount j. Mount b. Poruk K. Tice M. Stauffer j.A. Department of Surgery Mayo Clinic Jacksonville FL United States Medical Education Heritage College of Osteopathic Medicine Ohio University Athens OH United States Medical Education The University of Toledo College of Medicine and Life Sciences Toledo OH United States

Objective: In previous studies, laparoscopic pancreaticoduodenectomy (LPD) has demonstrated safety and potential benefits over open pancreaticoduodenectomy (OPD) for pancreatic adenocarcinoma (PDAC). After performing both LPD and OPD procedures interchangeably in routine practice for a decade, the outcomes of LPD versus OPD for PDAC were analyzed and compared at a single institution. Our primary aim was to compare features of LPD and OPD in PDAC patients so that the suitable surgical approach may be chosen for each individual. Methods: From january 2010 through December 2020, all patients undergoing pancreaticoduodenectomy (PD) were identified, and information was collected prospectively. At a single institution, PD was performed on 589 patients, of whom 347 were OPD patients and 242 were LPD patients. After excluding those who underwent pancreatectomy for indications other than PDAC, total pancreatectomy, major vascular or concomitant organ resection, there were 237 patients (OPD = 157, LPD = 80). Then propensity score matching was completed to analyze 77 OPD patients versus 77 LPD patients to create a similar group of patients who underwent either LPD or OPD for PDAC. A comparison of perioperative data and 90-day outcomes with subsequent statistical analysis was performed. Results: Operative time (491 min vs. 281 min, p but overall morbidity was similar. blood loss, mortality and post-pancreatectomy hemorrhage were also similar for both groups, but total costs ($60,245 vs. $50,900, p = 0.002) were significantly higher for LPD than OPD. Recurrence and overall survival were similar for the two groups. Conclusion: In our experience, LPD does not offer any advantages over OPD for PDAC and is associated with a higher rate of complications and costs. © 2024 Zhejiang University

关键词： Laparoscopy Pancreatic ductal adenocarcinoma Pancreatic fistula Pancreaticoduodenectomy Whipple

Carbon Monoxide as C1 building block in Fine Chemical Synthesis

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Chinese journal of Chemistry 2024年第2期42卷 199-221页

作者： Rui M.b.Carrilho Mario j.F.Calvete Gabor Mikle Laszlo Kollar Mariette M.Pereira University of Coimbra Coimbra Chemistry CentreDepartment of ChemistryRua Larga3004-535 CoimbraPortugal Department of General and Inorganic Chemistry and ELKH-PTE Research Groupfor Selective Chemical Syntheses University of PecsIfjusag utja 6H-7624 PecsHungary

Carbon monoxide(CO)has become one of the most relevant and versatile renewable C1 building blocks for chemical synthesis,especially in the fine chemicals industry,due to the development of efficient and selective catalysts for its *** this review,we present a comprehensive critical analysis of the last 10 years literature on the use of CO as a renewable feedstock for fine chemicals *** review is organized by type of catalytic reaction,namely alkene and alkyne carbonylation,hydroformylation,carbonylation of aryl halides,carbonylative cross-coupling and C-H *** examples of the synthesis of relevant building blocks and/or known pharmaceuticals are *** is placed on examples of utilizing CO as the C1 building block in one or more catalytic *** catalyst used and the reaction conditions are consistently presented throughout all of the examples.

关键词： Carbon monoxide Fine chemicals Carbonylation Hydroformylation C-H functionalization