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Retention and Mobility of Copper and Lead in Soils as Influenced by Soil Horizon Properties

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Pedosphere 2011年第5期21卷 603-614页

作者： B.CERQUEIRA E.F.COVELO M.L.ANDRADE F.A.vega Department of Plant Biology and Soil Science University of Vigo

The mobility and bioavailability of heavy metals in soils is largely governed by sorption and desorption ***2+ and Pb2+ are among the most potentially toxic heavy metals and they are present,often concomitantly,in many polluting spills and in *** objective was to assess and compare the competitive sorption and desorption capacities and sorption hysteresis of Cu2+ and Pb2+,as well as their migration through the profiles of four natural soils:a Humic Umbrisol,an Umbric Cambisol,an Endoleptic Luvisol and a Humic *** all horizons Pb2+ was invariably sorbed and retained to a greater extent than Cu2+.The sorption and retention of Cu2+ were most in?uenced by pH,e?ective cation exchange capacity(CECe) and Mn oxide *** the other hand,the fixation capacity of Pb2+ was most in?uenced by pH,CECe,and Mn oxide and organic matter *** and CECe were the individual soil properties most markedly in?uencing Cu2+ and Pb2+ sorption and *** all the horizons Pb2+ exhibited greater hysteresis than Cu2+.In each soil the hysteresis in the A horizon was greater than that in the B horizon,except in the Bt horizon of the Endoleptic Luvisol,due to its high pH and vermiculite *** on migration indices,Pb2+ was less mobile than Cu2+ in the studied soils.

关键词： desorption heavy metal hysteresis migration sorption

Hadronic spectra from deformed AdS backgrounds

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Chinese Physics C 2020年第6期44卷 109-122页

作者： Eduardo Folco Capossoli Miguel Angel Martín Contreras Danning Li Alfredo vega Henrique Boschi-Filho Instituto de Física Universidade Federal do Rio de Janeiro21.941-972-Rio de Janeiro-RJ-Brazil Departamento de Física/Mestrado Profissional em Práticas da Educação Básica(MPPEB) Colégio Pedro II20.921-903-Rio de Janeiro-RJ-Brazil Instituto de Física y Astronomía Universidad de ValparaísoA.Gran Bretaña 1111ValparaísoChile Department of Physics and Siyuan Laboratory Jinan UniversityGuangzhou 510632China

Because of the presence of modified warp factors in metric tensors,we use deformed AdS5 spaces to apply the AdS/CFT correspondence to calculate the spectra for even and odd glueballs,scalar and vector mesons,and baryons with different *** the glueball cases,we derive their Regge trajectories and compare them with those related to the pomeron and the *** the scalar and vector mesons,as well as baryons,the determined masses are compatible with the *** particular,for these hadrons we found Regge trajectories compatible with another holographic approach as well as with the hadronic spectroscopy,which present an universal Regge slope of approximately 1.1 GeV^2.

关键词： hadronic spectra AdS/QCD model Regge trajectories

基于机器学习的刀具磨损状态智能预测方法研究

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机电工程技术 2024年第2期53卷 29-34,123页

作者：梁璐娜魏建安袁雅阁吴国阳徐军贵州大学机械工程学院贵阳550025

以刀具为研究载体,运用人工智能和智能优化等先进技术,成功实现了刀具磨损状态的智能预测。研究重点在于建立有效的刀具磨损状态预测方法,全面解析刀具磨损机理、形式及磨钝标准等关键信息。同时,构建了自采刀具磨损状态监测平台,以便... 详细信息

以刀具为研究载体,运用人工智能和智能优化等先进技术,成功实现了刀具磨损状态的智能预测。研究重点在于建立有效的刀具磨损状态预测方法,全面解析刀具磨损机理、形式及磨钝标准等关键信息。同时,构建了自采刀具磨损状态监测平台,以便收集并处理相关数据。在数据处理过程中,采用小波滤噪和EMD-Shannon能量熵进行特征筛选,构建出特征空间数据集,为后续构建预测模型提供坚实的数据基础。结合支持向量机分类算法和智能优化算法,构建出刀具磨损状态的智能预测框架。此框架不仅提高了预测精度,也为维护人员提供了强有力的工具,利于更好地进行刀具磨损状态的预测和维护工作。为增强实际应用价值,将所取得的成果整合至基于MATLAB GUI的刀具磨损状态智能监测原型系统,以图形界面方式呈现预测结果,使用户直观地了解和掌握刀具的磨损状态。结果表明,该方法具有高精度,刀具磨损状态的识别精度可达84%,为相关领域提供了可靠的技术支持。

关键词：刀具磨损智能监测系统特征选择智能优化算法支持向量机

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Analysis and Prediction of Corrosion Risk in Atmospheric Distillation Tower Overhead System

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China Petroleum Processing & Petrochemical Technology 2021年第1期23卷 21-30页

作者： Niu luna Han Lei Chen Wenwu Pan Long Zhang Yanling Qu Dingrong State Key Laboratory of Safety and Control for Chemicals SINOPEC Research Institute of Safety EngineeringQingdao 266101

In order to optimize the atmospheric tower overhead low-temperature system,the physical parameters,multiphase composition,aqueous dew point temperature,and ammonium salt crystallization temperature are simulated with process simulation *** temperature distribution in overhead heat exchanger is calculated by heat transfer *** special parts with elbows near the inlet and outlet of heat exchanger are studied by fluid field *** indicate that under current operating conditions,the aqueous dew point temperature and initial crystallization temperature of NH4Cl are 91°C and 128°C,*** salt appears in the distillation tower and liquid water occurs in heat exchanger tubes,in which the dew point induced corrosion is the most direct factor for heat exchanger *** the heat exchanger,condensate water appearing in the area 2.7 meters away from the bundle inlet can give rise to corrosion risk under the moist NH4Cl and high concentration of acidic solution *** the pipes and elbows located near the inlet and the outlet of heat exchanger,the flow field presents an unsymmetrical *** risk areas are mainly concentrated on the external bend of elbows where the liquid water concentration is *** coupling of simulation methods established thereby is approved as an effective way to evaluate the corrosion risk in the atmospheric column overhead system and can provide a scientific basis for corrosion control.

关键词： atmospheric tower overhead simulation corrosion ammonium salt crystallization fluid field

不同粒径多花黄精粉物理特性及体外模拟胃肠消化特性研究

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食品工业科技 2024年第21期45卷 93-102页

作者：赵晨晨吕家慧刘畅童若楠王梦锦刘恒邢丽花于娇耿璐娜俞年军安徽中医药大学药学院安徽合肥230012 省部共建安徽道地中药材品质提升协同创新中心安徽合肥230012 亳州学院安徽亳州236800 安徽敬道生物科技有限公司安徽亳州236814 直接口服中药饮片亳州市重点实验室安徽亳州236000

为探究超微粉碎处理对多花黄精粉特性的影响,本文采用粉碎过筛处理制备不同粒径(50、100、200、325目)多花黄精粉末,并用扫描电子显微镜及傅里叶红外光谱对其物理特性开展研究,同时模拟体外胃肠消化过程。结果表明,经过粉碎及过筛处理后... 详细信息

为探究超微粉碎处理对多花黄精粉特性的影响,本文采用粉碎过筛处理制备不同粒径(50、100、200、325目)多花黄精粉末,并用扫描电子显微镜及傅里叶红外光谱对其物理特性开展研究,同时模拟体外胃肠消化过程。结果表明,经过粉碎及过筛处理后,多花黄精粉粒径大小具有显著性差异(P<0.05)。粉碎过程仅破坏了粉体的表面结构,并未破坏粉体的分子结构。多花黄精粉的休止角、溶解度随粒径的减小不断增加,而堆密度、润湿时间、持水力不断下降。此外,粉碎度为200目(75μm,超微粉Ⅰ)的粉体活性物质多糖含量为15.37%,显著高于其他样品(P<0.05)。体外模拟胃肠消化过程中,粉碎度为200目(75μm,超微粉Ⅰ)的粉体多糖释放量最高,且具有一定体外抗氧化能力。综上,多花黄精粉碎时粉体过200目筛时,多糖释放量最高。本实验为多花黄精粉末的产业化应用提供了理论依据。

关键词：多花黄精超微粉粒径粉体特性模拟胃肠消化抗氧化

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On Lagrange-Projection Schemes for Shallow Water Flows Over Movable Bottom with Suspended and Bedload Transport

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Numerical Mathematics(Theory,Methods and Applications) 2023年第4期16卷 1087-1126页

作者： Alessia Del Grosso Manuel J.Castro Díaz Christophe Chalons Tomás Morales de luna UniversitéParis-Saclay UVSQCNRSLaboratoire de Mathématiques de Versailles78000VersaillesFrance Dpto.de Análisis Matemático Facultad de CienciasUniversidad de MálagaCampus de Teatinos S/N29081 MálagaSpain

In the present work we aim to simulate shallow water flows over movable bottom with suspended and bedload *** order to numerically approximate such a system,we proceed step by *** start by considering shallow water equations with non-constant density of the mixture ***,the Exner equation is included to take into account bedload sediment ***,source terms for friction,erosion and deposition processes are ***,observe that the sediment particle could go in suspension into the water or being deposited on the *** the numerical scheme,we rely on well-balanced Lagrange-projection *** particular,since sediment transport is generally a slow process,we aim to develop semi-implicit schemes in order to obtain fast *** Lagrange-projection splitting is well-suited for such a purpose as it entails a decomposition of the(fast)acoustic waves and the(slow)material waves of the ***,in subsonic regimes,an implicit approximation of the acoustic equations allows us to neglect the corresponding CFL condition and to obtain fast numerical schemes with large time step.

关键词： Shallow water flows movable bottom erosion-deposition processes Lagrangeprojection schemes implicit-explicit schemes

Exploring kidney biopsy findings in congenital heart diseases:Insights beyond cyanotic nephropathy

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World Journal of Nephrology 2024年第1期13卷 25-32页

作者： Jose Daniel Juarez-Villa Iván Zepeda-Quiroz Sebastián Toledo-Ramírez Victor Hugo Gomez-Johnson Francisco Pérez-Allende Brian Ricardo Garibay-vega Francisco E Rodríguez Castellanos Bernardo Moguel-González Edgar Garcia-Cruz Salvador Lopez-Gil Department of Nephrology Instituto Nacional de Cardiología Ignacio ChavezMexico City 14080Mexico Congenital Heart Disease Instituto Nacional de Cardiología Ignacio ChavezMexico City 14080Mexico

BACKGROUND The association between congenital heart disease and chronic kidney disease is well *** mechanisms of kidney damage associated with congenital heart disease have been *** etiology of kidneydisease has commonly been considered to be secondary to focal segmental glomerulosclerosis(FSGS),however,this has only been demonstrated in case reports and not in observational or clinical *** To identify baseline and clinical characteristics,as well as the findings in kidney biopsies of patients with congenital heart disease in our *** This is a retrospective observational study conducted at the Nephrology Depart-ment of the National Institute of Cardiology“Ignacio Chávez”.All patients over 16 years old who underwent percutaneous kidney biopsy from January 2000 to January 2023 with congenital heart disease were included in the *** Ten patients with congenital heart disease and kidney biopsy were *** average age was 29.00 years±15.87 years with pre-biopsy proteinuria of 6193 mg/24 h±6165 mg/24 *** most common congenital heart disease was Fallot’s tetralogy with 2 cases(20%)and ventricular septal defect with 2(20%)*** the 10 cases,one case of IgA nephropathy and one case of membranoproliferative glomerulonephritis associated with immune complexes were found,receiving specific treatment after histopathological diagnosis,delaying the initiation of kidney replacement *** remaining 8 cases(80%),one case of FSGS with perihilar variety was found,while the other 7 cases were non-specific *** Determining the cause of chronic kidney disease can help in delaying the need for kidney replacement *** 2 out of 10 patients in our study,interventions were performed,and initiation of kidney replacement therapy was *** studies are needed to determine the usefulness of kidney biopsy in patients with congenital heart disease.

关键词： Renal biopsy Congenital heart disease Chronic kidney disease Focal segmental glomerulosclerosis

Biodegradable stents in gastrointestinal endoscopy

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World Journal of Gastroenterology 2014年第9期20卷 2212-2217页

作者： Vicente Lorenzo-Zú?iga Vicente Moreno-de-vega Ingrid Marín Jaume Boix Endoscopy Unit Department of Gastroenterology Hospital Universitari Germans Trias i Pujol 08916 Badalona Spain Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD) 08916 Badalona Spain

Biodegradable stents(BDSs)are an attractive option to avoid ongoing dilation or surgery in patients with benign stenoses of the small and large *** experience with the currently the only BDS for endoscopic placement,made of Poly-dioxanone,have shown promising *** some aspects should be improved as are the fact that BDSs lose their radial force over time due to the degradable material,and that can cause stent-induced mucosal or parenchymal *** complication rate and modest clinical efficacy has to be carefully considered in individual patients prior to placement of ***,the price of these stents therefore it is nowadays an important limitation.

关键词： Biodegradable stents Strictures Endoscopy Endoscopic placement Stenoses

The Teodorescu Operator in Clifford Analysis

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Chinese Annals of Mathematics,Series B 2012年第4期33卷 625-640页

作者： F.BRACKX H.De SCHEPPER M.E. luna-ELIZARRARS M.SHAPIRO Clifford Research Group Faculty of Engineering and Architecture Ghent University Belgium Instituto Politcnico Nacional Mexico City Mexico

Euclidean Clifford analysis is a higher dimensional function theory centred around monogenic functions, i.e., null solutions to a first order vector valued rotation in- variant differential operator called the Dirac operator. More recently, Hermitian Clifford analysis has emerged as a new branch, offering yet a refinement of the Euclidean case; it focuses on the simultaneous null solutions, called Hermitian monogenic functions, to two Hermitian Dirac operators and which are invariant under the action of the unitary group. In Euclidean Clifford analysis, the Teodorescu operator is the right inverse of the Dirac operator __0. In this paper, Teodorescu operators for the Hermitian Dirac operators c9~_ and 0_~, are constructed. Moreover, the structure of the Euclidean and Hermitian Teodor- escu operators is revealed by analyzing the more subtle behaviour of their components. Finally, the obtained inversion relations are still refined for the differential operators is- suing from the Euclidean and Hermitian Dirac operators by splitting the Clifford algebra product into its dot and wedge parts. Their relationship with several complex variables theory is discussed.

关键词： Clifford analysis Teodorescu operator Dirac operator