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Influence of the interaction of calcium carbonate particles with surfactants on the degree of water pollution in small rivers

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Ecological Processes 2017年第1期6卷 184-191页

作者： petru Spataru Francisco Fernandez Joseph W.Sista Tudor Spataru Oxana Spinu Igor Povar Institute of Chemistry of the Academy of Sciences of Moldova 3 Academiei str.ChisinauMD 2028Republic of Moldova Natural Sciences Department Hostos Community College500 Grand ConcourseBronxNY 10451USA Chemistry Department Columbia University3000 BroadwayNew YorkNY 10027USA.

Introduction:The influence of the interaction of calcium carbonate(CaCO3)and surface-active substances(SAS;surfactants)with different chain lengths and cationic and anionic hydrophilic centers has been ***:Laboratory simulations indicate reduced negative influences on cationic SAS nitrification/self-purification processes in the presence of anionic *** suggests the role of complex ionic formation[anionic SAS*cationic SAS]as a cause of this ***-Vis spectra of lauryl sulfate(LS)and of cetyltrimethylammonium(CTMA),as well as of their mixtures in ratios of 2:1 and 1:1,treated by fine particles of CaCO3,display decreased amounts of SAS in analyzed solutions and their presence on the surface of CaCO3 ***-Vis spectra reveal the decomposition of the complex[anionic SAS(SAS-An)*cationic SAS(SAS-Ct)]in solutions when CaCO3 is *** can be bonded by LS through hydrophobic chains,on the surface of CaCO3 ***,CaCO3 modifies the nature of LS and CTMA *** leads to an increased degree of toxicity of cationic SAS in aquatic *** amounts of CTMA in aqueous solutions are diminished in the presence of ammonium ion NH4+(2 mg/L).In the presence of two orders higher concentration of ammonium ion,this effect strongly increases,making the association *** structure of cationic SAS does not influence this *** obtained results have been confirmed both by timed natural aquatic sample analysis and laboratory simulations using water from Moldovan small rivers(Isnovat,Raut,and Bic).Conclusions:UV-Vis spectra and laboratory simulations demonstrate the change due to the addition of calcium *** and laboratory tests of water samples from Isnovat,Bic,and Raut Rivers,establish the cationic SAS negative influence on treatment and self-purification processes.

关键词： Anionic and cationic surface-active substances Calcium carbonate Small rivers Cetyltrimethylammonium Lauryl sulfate Tetrabutylammonium Toxicity Water pollution

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Transit time ultrasound perivascular flow probe technology is superior to MR imaging on hepatic blood flow measurement in a porcine model

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Hepatobiliary & Pancreatic Diseases International 2018年第6期17卷 538-545页

作者： Mohamed Bekheit Chloe Audebert petru Bucur Hans Adriaensen Emilie Bled Mylène Wartenberg Irene Vignon-Clementel Eric Vibert Inserm Unité 1193 112 Boulevard Paul Valliant CuturierVillejuifFrance Institute of medical sciences University of AberdeenAberdeenUK Centre de recherche Inria de Paris ParisFrance Sorbonne Universités UPMC University of Paris 6Laboratoire Jacques-LouisLionsParisFrance CHRU hopitaux de ToursChirurgie Héato-biliaire et pancréatiqueTransplantation HéatiqueToursFrance Plateforme Chirurgie et Imagerie pour le Recherche et l’Enseignement(CIRE) ImagerieUMR-PRC37380 NouzillyCentre INRA Val de LoireFrance AP-HP Hoital Paul BrousseCentre Héato-BiliaireVillejuifFrance

Background: The hepatic hemodynamics is an essential parameter in surgical planning as well as in various disease processes. The transit time ultrasound(TTUS) perivascular flow probe technology is widely used in clinical practice to evaluate the hepatic inflow, yet invasive. The phase-contrast-MRI(PC-MRI) is not invasive and potentially applicable in assessing the hepatic blood flow. In the present study, we compared the hepatic inflow rates using the PC-MRI and the TTUS probe, and evaluated their predictive value of post-hepatectomy adverse events. Methods: Eighteen large white pigs were anaesthetized for PC-MRI and approximately 75% hepatic resection was performed under a unified protocol. The blood flow was measured in the hepatic artery(Qha), the portal vein(Qpv), and the aorta above the celiac trunk(Qca) using PC-MRI, and was compared to the TTUS probe. The Bland-Altman method was conducted and a partial least squares regression(PLS) model was implemented. Results: The mean Qpv measured in PC-MRI was 0.55 ± 0.12 L/min, and in the TTUS probe was 0.74 ± 0.17 L/min. Qca was 1.40 ± 0.47 L/min in the PC-MRI and 2.00 ± 0.60 L/min in the TTUS probe. Qha was 0.17 ± 0.10 L/min in the PC-MRI, and 0.13 ± 0.06 L/min in the TTUS probe. The Bland-Altman method revealed that the estimated bias of Qca in the PC-MRI was 32%(95% CI:-49% to 15%); Qha 17%(95% CI:-15% to 51%); and Qpv 40%(95% CI:-62% to 18%). The TTUS probe had a higher weight in predicting adverse outcomes after 75% resection compared to the PC-MRI( β= 0.35 and 0.43 vs β = 0.22 and 0.07, for tissue changes and premature death, respectively). Conclusions: There is a tendency of the PC-MRI to underestimate the flow measured by the TTUS probes. The TTUS probe measures are more predictive of relevant post-hepatectomy outcomes.

关键词： Hepatic blood flow Phase contrast MRI Transit time ultrasound probe Porcine model Liver surgery

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Nanoparticles and Nanostructured Thin Films Based on Strong Polycations of Integral type

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复旦学报（自然科学版） 2005年第5期44卷 855-856页

作者： E. S. Dragan M. mihai S. Schwarz "petru Poni" Institute of Macromolecular Chemistry Iasi 700487 Romania"Petru Poni" Institute of Macromolecular Chemistry Iasi 700487 RomaniaInstitute of Polymer Research Dresden 01069 Germany

Nonstoichiometric interpolyelectrolyte complexes (NIPECs) as nanoparticles, on the one side, and nanostructured thin films with controlled architecture, deposited on some planar surfaces, on the other side,have been designed by eco-friendly techniques using strong polycations (PC) containing quaternary ammonium groups in the backbone and either strong polyanions or multicharged azo dyes.

关键词：纳米离子纳米结构薄膜密度分布电子散射聚阳离子

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Convergence and Error of Some Numerical Methods for Solving a Convection-Diffusion Problem

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Applied Mathematics 2013年第5期4卷 72-79页

作者： Gabriela Nut Ioana Chiorean petru Blaga Applied Mathematics Department Babes-Bolyai University Cluj Napoca Romania

We use the local Fourier analysis to determine the properties of the multigrid method when used in modeling the skin penetration of a drug. The analyses of these properties can be very in designing an efficient structure of the multigrid method and in comparing the element and finite difference discretization techniques. After the theoretical results obtained, we also present some numerical results for a problem for which the solution is known.

关键词： Time Dependent Convection Diffusion Multigrid Method Finite Element and Finite Differences Discretization

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电子商务应用：一个基于多层架构的在线商场

电子商务应用：一个基于多层架构的在线商场

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作者： Hileni petru Josephat 河海大学

学位级别：硕士

当今,Internet的使用遍及人类社会的各个方面,它给人们的生活带来了各种各样的变化,而电子商务就是其中之一。通过Internet处理事务,无数的个人和商业行为更多的获益。电子商务对传统的商业运作产生了巨大的影响。任何设计能否获得成... 详细信息

当今,Internet的使用遍及人类社会的各个方面,它给人们的生活带来了各种各样的变化,而电子商务就是其中之一。通过Internet处理事务,无数的个人和商业行为更多的获益。电子商务对传统的商业运作产生了巨大的影响。任何设计能否获得成功的一个关键因素是其系统架构是否合理可行。本文论述一种电子商务应用,它是基于多层架构的网上交易系统。多层架构是一种发展趋势,对企业级运用和基于web的运用产生了深远影响。在线交易系统运行在计算机上,能够通过网络完成在线订货和在线支付。随着在线客户的不断增加,需要系统能够尽量不出错并且随时能够提供服务。因此,本系统在电子商务领域具有很高的可靠性,安全性,灵活性。在三层结构(即多层结构),中间层位于系统客户端和远端数据库之间。中间层把客户端界面和数据独立出来,这样就提高了整个系统的灵活性,高性能,可伸缩性,可管理性,安全性和可扩展性。在本文阐述的多层架构中,客户端和数据库可以通过中间层进行通信,为客户提供高质量的服务,而这一点也是该架构能为电子商务提供的。由于Web的大范围应用,Internet标准极大的改变着分布式计算。基于Web的多层架构是基于组件的两层结构的理想发展方向,也比较适合小型网上交易。这种架构正随着网络的发展越来越流行,可以预见在近些年中,这种分布式系统将会得到极大的发展。

关键词： Internet 电子商务多层架构在线交易 Web应用商业逻辑

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Using a Computer Driven PID Regulator for Controlling the Vacuum Pump of a Mechanical Milking Machine

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Computer Technology and Application 2013年第8期4卷 395-399页

作者： Rsca Radu Carlescu petru Tenu loan Faculty of Agriculture University of Agricultural Sciences and Veterinary Medicine Ia~i 700490 Romania

Conventional vacuum control in a milking system is accomplished by using a vacuum pump, sized for the maximum air flows into the milking system, running at a full speed. The difference between the pump capacity and the necessary flow of air is compensated by allowing air to enter the system through a regulator. The solution presented in this paper uses a VFD （variable frequency driver） in order to drive the vacuum pump at a controlled speed, so that the air removed equals the air entering the milking system. The VFD technology is able to adjust the rate of air removal from the milking system, by changing the speed of the vacuum pump motor. The VFD is controlled by a computer using a virtual instrument in order to emulate a PID （proportion integration differentiation） regulator. The tests aimed to evaluate the vacuum regulator characteristics and vacuum stability. A statistical analysis of the experimental results was performed and it showed that there was a significant difference between the experimental results obtained for the two methods of vacuum regulation （with vacuum regulator and VFD controller respectively）. The experimental results proved that the used of the VFD controller led to a higher vacuum stability in terms of the error between the set vacuum value and the achieved values.

关键词： Variable frequency drive milking equipment vacuum stability.

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FEM Study of the Strain Kinematics in the 3D Nanofibrous Structure Prepared by the Electrospinning Process

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Applied Mathematics 2013年第5期4卷 80-90页

作者： Michal petru Ondrej Novak David Vejrych Petr Lepsik Institute for Nanomaterials Advanced Technologies and InovationTechnical University of LiberecLiberecCzech Republic Department of Nonwovens Technical University of LiberecLiberecCzech Republic Department of Machine Elements and Mechanism Technical University of LiberecLiberecCzech Republic

Finite element model (FEM) was used for the study and description of the arising 3D nanofiber structure strain caused by the pressure of the flowing gas. Computer simulation using an adaptive networking through implicit FEM algorithm can be utilized for a significant improvement of the study of anisotropic strain in the deformed 3D nanostructure. The created model is based on the empirical Laplace-Poisson differential equation for the flow, where gas particles are moving with certain kinetic energy. The kinetic energy depends on the speed, time and temperature and affects the resulting strain of 3D nanofiber structure. The simulation results were compared to the results obtained from the image analysis of real samples and showed that this FEM model can determine individual phases of structure strain. The comparison shows that the developed FEM model can be an important tool in the study of the strain in the arising 3D nano- fiber structure and it can provide valuable information for optimization of 3D nanofiber structure production by the electrospinning process.

关键词： FEM Strain 3D Nanofibrous Structure Electrospinning Gas Flow

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Results Regarding Online Asset Management System for a Transformer Station

Results Regarding Online Asset Management System for a Trans...

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The 2012 International Conference on Advanced Material and Manufacturing Science (ICAMMS 2012)

作者： Puiu petru Gabriel Ababei Stefan University "Vasile Alecsandri"

This paper work presents results from the application of maintenance management system in a transformer *** this area of asset management,it is necessary to use the asset management（AM） methods to build a single structure,taking into account the principle of best investment ***,this paper presents the results obtained from a Lab View simulation for such a *** research has been made on the base of economic aspects,technical characteristics of the equipment and the parameters characterizing their operation.

关键词： Asset management transformer station LabView

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Could there be an interplay between periodontal changes and pancreatic malignancies?

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World Journal of Clinical Cases 2023年第3期11卷 545-555页

作者： Bogdan Silviu Ungureanu Dorin Nicolae Gheorghe Flavia Mirela Nicolae Sandu Ramboiu petru Adrian Radu Valeriu MarinȘurlin Victor Dan Eugen Strambu Dan Ionut Gheonea Alexandra Roman PetraȘurlin Department of Gastroenterology University of Medicine and Pharmacy of CraiovaCraiova 200349Romania Department of Periodontology Research Center of Periodontal-Systemic ImplicationsUniversity of Medicine and Pharmacy of CraiovaCraiova 200349Romania Department 1st of Surgery University of Medicine and Pharmacy of CraiovaCraiova 200349Romania Department of General Surgery “Carol Davila”University of Medicine and PharmacyBucharest 020021Romania Department of Periodontology "Iuliu Hațieganu"University of Medicine and PharmacyCluj-Napoca 400012Romania

The term"periodontal disease"refers to a group of chronic inflammatory illnesses caused by specific microorganisms from subgingival biofilm,that affect the toothsupporting *** research has also shown that periodontal infection plays a role in aggravating systemic disease states at distal sites,reinforcing the significance of the oral cavity for general ***,it has been suggested that gastroenterological malignancies may be promoted by hematogenous,enteral or lymphatic translocation of *** the past 25 years,the global burden of pancreatic cancer(PC)has more than doubled,making it one of the major causes of cancer-related *** has been linked to at least 50%increased risk of PC and it could be considered a risk factor for this malignancy.A recent study performed on 59000 African American women with a follow up of 21 years showed that participants who had poor dental health had higher chances of *** findings,according to researchers,might be related to the inflammation that some oral bacteria *** the mortality of PC,periodontitis considerably raises the chance of dying from *** alterations in the gut,oral cavity and pancreatic tissues of PC patients occur when compared to healthy flora,demonstrating a link between PC and *** may also contribute to PC development,although the underlying pathway is not yet *** function of the microbiome in PC risk has drawn more focus over the last *** risk of PC has been linked to the oral microbiome,specifically increased levels of Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans and decreased relative abundance of Leptotrichia and Fusobacteria,suggesting that it may have an impact on the inflammatory condition by expanding,altering,and regulating the commensal *** who received periodontal treatment had significantly decreased incidence rate ratios for *** analyzing patterns in

关键词： Periodontal disease Pancreatic cancer Microbiome Periodontitis Periopathogens Periodontal medicine

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Performance Evaluation of the Fe-IR-120（Na）-DEHPA Impregnated Resin in the Removal Process of As（V） from Aqueous Solution

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材料科学与工程（中英文B版） 2011年第4期1卷 421-432页

作者： Mihaela Ciopec Adina Negrea Lavinia Lupa Comeliu Davidescu petru Negrea Paula Sfarloaga Faculty of Industrial Chemistry and Environmental Engineering University ＂Politehnica＂ Timisoara Piata Victoriei No.2Timisoara 300006 Romania National Institute for Research and Development in Electrochemistry and Condensed Matter Timisoara Plautius AndronescuNo. 1 Timisoara 300224 Romania

In the present paper the performance of a new functionalized material Fe-IR-120(Na)-DEHPA in the removal process of As(V) from aqueous solutions, has been investigated. The new material was obtained trough impregnation of Amberlite IR-120(Na) with di(2-ethylhexyl) phosphoric acid (DEHPA) trough the dry method. Trough impregnation of the Amberlite IR-120(Na) was obtained a resin with two functional groups which was further loaded with Fe(III) ions because of the high affinity of arsenic towards iron. The physicochemical methods of analysis (FTIR spectroscopy, EDX and SEM) approved that the impregnation with DEHPA and the iron loading, respectively, occurred. By applying the kinetic model to the experimental data it was found that the removal of As(V) ions by Fe-IR-120(Na)-DEHPA follows the pseudo-second-order rate kinetics. The linear Langmuir and Freundlich isotherm models were used to represent the experimental data and these could be well interpreted by the Langmuir isotherm. RL values between 0 and 1.0 further indicate a favorable adsorption of As(V) ions onto Fe-IR-120(Na)-DEHPA. The maximum As(V) ions uptake calculated from Langmuir model was 21.8 μg/g.

关键词： DEHPA 浸渍树脂水溶液 Langmuir模型 IR NA 搬运过程绩效评价

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