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Comparative equilibrium studies of sorption of Pb(Ⅱ) ions by sodium and calcium alginate

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Journal of Environmental Sciences 2008年第7期20卷 827-831页

作者： KHOTIMCHENKO Maxim KOVALEV Valeri KHOTIMCHENKO yuri Department of pharmacy Vladivostok State Medical UniversityVladivostok 690990Russia Laboratory of Pharmacology Institute of Marine BiologyFar East Branch of Russian Academy of SciencesVladivostok 690041Russia. Laboratory of Pharmacology Institute of Marine BiologyFar East Branch of Russian Academy of SciencesVladivostok 690041Russia.Department of pharmacyVladivostok State Medical UniversityVladivostok 690990Russia

The absorption of Pb(Ⅱ) ions from aqueous solution by different alginate compounds was studied in a batch sorption *** soluble sodium alginate and insoluble calcium alginate beads were *** lead-binding capacity of both alginate compounds was highest within the pH range *** binding capacities and rates of Pb(lI) ions by alginate compounds were *** Langmuir,Freundlich,and Bruneaur,Emmet and Teller (BET) sorption models were applied to describe the isotherms and isotherm con...

关键词： heavy metal lead equilibrium study alginate wastewater

Analysis of the Cicatricial Acceleration Method (MAC®) in Skin Repair in Wistar Rattus norvegicus with Induced Chemical Burns

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Journal of Biosciences and Medicines 2024年第9期12卷 204-214页

作者： Marcus Vinicius de Mello Pinto Sandroval Francisco Torres Aline Ronis Sampaio Karin yuri Fernandez Iturra Miriam Viviane Baron Patricia Froes Carlos Ruiz da Silva Daiane Paza Maria Elena Silva Alvarez Josefa Jeanette Ugalde Juliano Tibola Esteban Fortuny Celulare Institute Petrpolis Brazil State University of Santa Catarina (UDESC) Florianopolis Brazil Bienus Clinic Santiago Chile Pontifical Catholic University of Rio Grande do Sul (PUC/RS) Porto Alegre Brazil International Research Group (IRG) Natal Brazil Academic Training Center (CTA) College So Paulo Brazil Fibrafisio Clinic Brusque Brazil Fisiocare Clinic Curic Chile Lua Clinic Coyhaique Chile Finis Terrae University Santiago Chile

Introduction: The cicatricial acceleration method (MAC®) promotes photobiological effects of an anti-inflammatory and healing nature. Its therapeutic radiation is emitted, producing photobiostimulant effects that result in rapid tissue repair and better tissue quality. The treatment of burns has always been a challenge, which involves both performing surgery and controlling and guiding scar regeneration, avoiding possible morbidities. Objective: To evaluate the effects of applying the MAC methodology with an AlGa (aluminum, gallium arsenide) laser on the time and quality of tissue repair in the skin of rats after induced chemical burns. Method: 22 adult male rats were subjected to a second-degree chemical burn on the back using 50% trichloroacetic acid. After the burns, the animals were randomly separated into 2 groups: control and experimental. The control group (G1) received placebo laser therapy and the laser group (G2) underwent laser irradiation with an energy density of 100 J/cm2. Histological analysis and macroscopic evaluation were carried out by means of the paper template method. Results: Group G1 showed (53%) of the necrosis area and group G2 showed (11%) necrosis area. Conclusion: The cicatricial acceleration method (MAC®) favored the repair of wounds caused by a 2nd-degree chemical burn, optimizing time and improving quality.

关键词： Chemical Burn Healing Scarring Cicatricial Acceleration Method (MAC®) Tissue Repair

Schreier rewriting beyond the classical setting Dedicated to our teacher Alfred Lvovich Shmelkin on his 70th birthday

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Science China Mathematics 2009年第2期52卷 231-243页

作者： BAHTURIN yuri OLSHANSKII Alexander Department of Mathematics and Statistics Memorial University of Newfoundland St. John'sNL A1C 5S7Canada Department of Algebra Faculty of Mathematics and Mechanics119899 Moscow Russia Department of Mathematics 1326 Stevenson Center Vanderbilt UniversityNashvilleTN 37240 USA

Using actions of free monoids and free associative algebras, we establish some Schreier-type formulas involving ranks of actions and ranks of subactions in free actions or Grassmann-type relations for the ranks of intersections of subactions of free actions. The coset action of the free group is used to establish a generalization of the Schreier formula in the case of subgroups of infinite index. We also study and apply large modules over free associative and free group algebras.

关键词： free algebra group monoid act G-set module

Evaluation of Energy Saving Operational Modes for Industrial Fracture Connected Processes on the Basis of Incubation Time Fracture Criterion

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Transactions of Tianjin University 2008年第B10期14卷 476-482页

作者： Bratov Vladimir Petrov yuri InstituteofProblemsofMechanicalEngineering 199178St.-PetersburgRussia St.-PetersburgStateUniversity 198504St.-PetersburgRussia

A problem for a central crack in a plate subjected to plane strain conditions is investigated. Mode I crack loading is created by a dynamic pressure pulse applied at a large distance from the crack. It was found that for a certain combination of amplitude and duration of the pulse applied, the energy transmitted to the sample has a strongly marked minimum, meaning that with the pulse amplitude or duration moving away from the optimal values, minimum energy required for initiation of crack growth increases rapidly. The results obtained indicate a possibility to optimise energy consumption of different industrial processes connected with fracture. Much could be gained in, for example, drilling or rock pounding where energy input accounts for the largest part of the process cost. Presumably further investigation of the effect observed can make it possible to predict optimal energy saving parameters, i.e. frequency and amplitude of impacts, for industrial devices, e.g. bores, grinding machines, and hence significantly reduce the process cost. The pre- diction can be given based on the parameters of the media fractured （material parameters, prevalent crack length and orientation, etc.）.

关键词： fracture energy saving incubation time fracture criterion

Atomic-scale mechanisms of void strengthening in tungsten

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Tungsten 2021年第1期3卷 65-71页

作者： yuri N.Osetsky Materials Science and Technology Division Oak Ridge National LaboratoryOak RidgeTN 37831USA

Neutron and heavy-ion irradiation of tungsten produces nanometer-size vacancy voids,gas-filled bubbles and dislocation *** defect features can a ect mechanical properties and the impact can be quite significant because of their high *** the basic mechanisms of mechanical properties degradation is necessary for predicting radiation e *** can be made using discrete dislocation dynamics or/and finite element approaches which,however,need local interaction mechanisms as *** knowledge can be provided only by atomic-scale *** paper reports the results of an extensive atomic-scale modeling study of the interactions between moving edge dislocations and voids in *** main focus is on the e ects of the void size and ambient *** resolved shear stress was calculated for voids up to 9 nm in *** results are compared with the theoretical approach and with those obtained earlier for voids in body centered cubic(bcc)*** important role of the void surface has been revealed.

关键词： Tungsten Neutron irradiation Voids Radiation-induced hardening Dislocations Dispersed barrier hardening

Preparation of a Hybrid Organic-inorganic Monolith for Extraction and Purification of Quercetin and Myricetin from Chamaecyparis obtusa

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Chemical Research in Chinese Universities 2014年第2期30卷 216-221页

作者： ZHU Tao LEE yuri ROW Kyungho School of Chemistry and Chemical Engineering Tianjin University of Technology Tianjin 300384 P.R.China Department of Chemical Engineering Inha University Incheon 402-751 Korea

A new hybrid organic-inorganic monolithic cartridge was synthesized and used as the selective sorbent for the extraction and purification of quercetin and myricetin from Chamaecyparis obtusa via a solid-phase extraction *** morphology of the monolithic material was examined by field emission-scanning electron microscopy and a Brunauer-Emmett-Teller（BET） *** adsorption capacity of the obtained material for quercetin and myricetin was investigated by fitting the adsorption data to four different adsorption equations,of which the LangmuirFreundlich isotherm was selected as the most suitable *** optimized conditions,good calibration curves were observed at nine concentrations ranged from 0.5 μg/mL to 100.0 μg/mL of quercetin and *** extraction recovery ranged from 74.5％ to 84.6％ and the inter-and intra-day relative standard deviations were ＜6％.This type of hybrid monolith has potential for the separation and purification of bioactive compounds from natural plant extracts.

关键词： Extraction Purification Adsorption isotherm Hybrid organic-inorganic monolith Quercetin Myricetin

Recovery of Brachiopod and Ammonoid Faunas Following the End-Permian Crisis:Additional Evidence from the Lower Triassic of the Russian Far East and Kazakhstan

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Journal of Earth Science 2014年第1期25卷 1-44页

作者： yuri D Zakharov Alexander M Popov Far Eastern Geological Institute Far Eastern BranchRussian Academy of Sciences

After the End-Permian mass extinction, ammonoids reached levels of taxonomic diver- sity higher than in the Changhsingian by the Dienerian Substage of the Induan. However, brachiopods exhibit a prolonged delay in recovery, and their taxonomic diversity had not recovered to Late Permian levels even by the Olenekian. The differential patterns of recovery between these two clades may reflect fundamental differences in physiology and behavior. Brachiopods were benthic organisms that were dependent on specific trophic sources, and their general reduction in size during the Early Triassic may have been a response to a relative paucity of food resources. In contrast, ammonoids were sluggish- nektic organisms that utilized a wider range of trophic sources and that suffered no comparable size decrease during the Early Triassic. Brachiopods may have been at a disadvantage also due to vulner- abilities associated with their larval stage, during which they had to locate a suitable substrate for set- tlement. In contrast, ammonoids had no larval stage and juveniles may have been dispersed widely into favorable habitats. These factors may account for differences in the relative success of ammonoids and brachiopods at high-latitude regions following the End-Permian mass extinction： ammonoids success- fully reeolonized the Boreal region during the Early Triassic whereas brachiopods did not.

关键词： Lower Triassic South Primorye Kazakhstan brachiopod ammonoid biotic recovery.

Transient near tip fields in crack dynamics

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Science China(Physics,Mechanics & Astronomy) 2011年第7期54卷 1309-1318页

作者： BRATOV Vladimir PETROV yuri UTKIN Alexander Institute of Problems of Mechanical Engineering Russian Academy of SciencesSt.-Petersburg 199178Russia St.-Petersburg State University St.-Petersburg 198504Russia

Transient effects of stress-strain fields in the vicinity of a stationary crack tip under high rate loads are *** analytical solutions to near tip stresses are compared to fields prescribed by leading terms(one or several) of Williams asymptotic *** of load application mode,time(or,which is the same,distance from a crack tip) and Poisson's ratio on this discrepancy is extensively *** effects connected with crack tip propagation speed are also *** inconsistencies between real(or received in numerical solutions of state *** element computations) crack tip fields and stress intensity factor(SIF) singular field observed by numerous researchers are *** scope of problems where SIF field can be used for correct prediction of dynamic stress-strain fields in the crack tip region is *** to correctly approximate fields that are not SIF dominated,accounting additional terms of Williams expansion,is studied.

关键词： transient crack tip fields dynamic fracture high-rate loads asymptotic expansions

S. V. Kovalevskaya system, its generalization and discretization

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Frontiers of Mathematics in China 2013年第5期8卷 1047-1065页

作者： Matteo PETRERA yuri B. SURIS Institut fiir Mathematik MA 7-2 Technische Universitat Berlin Str. des 17. Juni 13610623 Berlin Germany

We consider an integrable three-dimensional system of ordinary differential equations introduced by S. V. Kovalevskaya in a letter to G. Mittag- Leffler. We prove its isomorphism with the three-dimensional Euler top, and propose two integrable discretizations for it. Then we present an integrable generalization of the Kovalevskaya system, and study the problem of integrable discretization for this generalized system.

关键词： Birational map integrable map algebraically integrable system