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SCIENTIFIC PRINCIPLES FOR MOdIFICATION OF WATER-SOLUBLE POLYMERS. FORMATION OF MACROMOLECULAR COMPLEXES

Chinese Journal of Polymer Science 1998年第3期16卷 268-278页

作者： PAUTOV V.d. ANUFRIEVA E.V. KRAKOVYAK M.g. Institute of Macromolecular Compounds RAS Bolshoy pr. 31 St. Petersburg 199004 RussiaInstitute of Macromolecular Compounds RAS Bolshoy pr. 31 St. Petersburg 199004 RussiaInstitute of Macromolecular Compounds RAS Bolshoy pr. 31 St. Petersburg 199004 Russia

The study of nanosecond dynamics of macromolecules with the lumines-cent methods make it possible to investigate the formation and functioning of polymericcomplexes, polymeric conjugates and macromolecular metal complexes, which are widelyused for solving many practical tasks. The nanosecond dynamics of macromolecules are ahighly sensitive indicator of interpolymer complexes (IPC) formation. It enables us to solvethe problems of studying IPC formation and stability and to investigate the interpolymerreactions of exchange and substitution. The investigation of changes in the rotational mo-bility of globular protein molecules as a whole makes it possible to determine the complexcomposition and its stability, and to control the course of polymer-protein conjugate forma-tion reaction. The nanosecond dynamics of polymers interacting with surfacants' ions (S)are the sensitive indicator of the S-polymer complex formation. A method for determin-ing the equilibrium constants of the S-polymer complex formation was developed on thebasis of the study of polymer chains mobility. It is established that nanosecond dynamicsinfluences the course of chemical reactions in polymer chains. Moreover, the marked effectof the nanosecond dynamics is also revealed in the study of photophysical processes (theformation of excimers and energy migration of electron excitation) in polymers with pho-toactive groups. It was found that the efficiency of both processes increases with increasingthe mobility of side chains, the carriers of photoactive groups.

关键词： Modification of water-soluble polymers Formation of complexes

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Effect of Some Heterocyclic derivatives on the Removal of Copper Ions from Wastewater by Cementation

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Journal of Materials Science & Technology 2004年第5期20卷 539-546页

作者： A.A.Taha M.g.Marei d.E.Abd El-khalek department of Chemistry Faculty of ScienceUniversity of AlexandriaAlexandriaEgyptDepartment of ChemistryFaculty of ScienceUniversity of AlexandriaAlexandriaEgyptDepartment of ChemistryFaculty of ScienceUniversity of AlexandriaAlexandriaEgypt

Removal of copper ions from copper sulphate solutions on a rotating zinc rod in absence and in presence of 3(2H)-furanones and 4H-pyran-4-one derivatives was investigated experimentally. Variables studied were initial copper ions concentration, rotational speed of the zinc rod, temperature and concentration of organic additives. It was found that cementation reaction is first order in presence and in absence of additives. Increasing concentration of initial copper ions, rotational speed of the zinc rod and temperature were found to increase the rate of cementation. In presence of organic additives an enhancement of the rate was observed, except in presence of methoxyfuranone the rate was found to decrease by an amount ranging from 11.74% to 33.79%. Rate acceleration or inhibition is associated mainly with changes in the structure of the additives as well as its concentration. The apparent activation energy for the cementation process in presence of different additives was estimated and was found to be ranged between 11.8 kJ/mol and 25.95 kJ/mol. These values suggest that the copper removal process in presence of these additives is controlled by diffusion. A scanning electron microscopy study of copper deposits obtained in presence of tolylfuranone, phenylpyrone and methoxyfuranone correlate with their behaviour during the kinetic study. different reaction conditions and the physical properties of solutions were studied to obtain dimensionless correlation among all these parameters. It was found that on applying cementation reaction on a sample from industrial wastewater in presence of phenylpyrone about 91.9% of Cu2+ are removed.

关键词： Cementation of copper Furanone and pyrone derivatives

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Effect of Rotation Rate on Microstructures and Mechanical Properties of FSW Mg-Zn-Y-Zr Alloy Joints

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Journal of Materials Science & Technology 2011年第12期27卷 1157-1164页

作者： g.M. Xie Z.Y. Ma Z.A. Luo P. Xue g.d. Wang The State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110819 China Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of SciencesShenyang 110016 China

Friction stir welding （FSW） of Mg-Zn-Y-Zr plates with 6 mm in thickness was successfully carried out under a wide range of rotation rates of 600-1200 r/rain with a constant traverse speed of 100 mm/min. After FSW, the coarse grains in the parent material （PM） were changed into fine equiaxed recrystallized grains at the＇nugget zone （NZ）. Furthermore, the coarse Mg-Zn-Y particles （W-phase） were broken up and dispersed homogenously into the Mg matrix. With increasing rotation rates, the size of the W-phase particles at the NZ significantly decreased, but the recrystallized grain size tended to increase. The hardness values of the NZs for all the FSW joints were higher than those of the PM, and the lowest hardness values were detected in the heat affected zone （HAZ）. The fracture occurred in the thermo-mechanical affected zone （TMAZ） on the advancing side for all the FSW joints in the tensile test, due to the incompatibility of the plastic deformation between the NZ and TMAZ caused by remarkably different orientation of grains and W-phase particles. The strength of FEW ioint reaches 90% of that of its PM

关键词： Friction stir welding Magnesium alloys Microstructure Mechanical property

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Seismic response of bridge pier on rigid caisson foundation in soil stratum

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Earthquake Engineering and Engineering Vibration 2008年第1期7卷 33-43页

作者： C. Tsigginos N. gerolymos d. Assimaki g. gazetas National Technical University of Athens Greece Civil Engineer Civil Engineering National Technical University of Athens Greece Lecturer Civil Engineering Georgia Institute of Technology Atlanta USA Assistant Professor Civil Engineering National Technical University of Athens Greece Professor

An analytical method to study the seismic response of a bridge pier supported on a rigid caisson foundation embedded in a deep soil stratum underlain by a homogeneous half space is developed. The method reproduces the kinematic and inertial responses, using translational and rotational distributed Winkler springs and dashpots to simulate the soil-caisson interaction. Closed-form solutions are given in the frequency domain for vertical harmonic S-wave excitation. Comparison with results from finite element （FE） analysis and other available solutions demonstrates the reliability of the model. Results from parametric studies are given for the kinematic and inertial responses. The modification of the fundamental period and damping ratio of the bridge due to soil-structure interaction is graphically illustrated.

关键词： caisson embedded foundations kinematic response inertial response Winkler model effective period effective damping

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Cryptotanshinone ameliorates cladribine-induced cognitive impairment in rats

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Asian Pacific Journal of Tropical Biomedicine 2023年第7期13卷 296-305页

作者： Khadga Raj Aran g.d.gupta Shamsher Singh Neuroscience division Department of PharmacologyISF College of Pharmacy(An Autonomous College)MogaPunjabIndia-142001 I.K.gujral Punjab Technical University JalandharIndia department of Pharmaceutics ISF College of PharmacyMogaPunjabIndia-142001

Objective:To evaluate the neuroprotective effect of cryptotanshinone against cladribine-induced cognitive impairment in ***:Rats were administered with cladribine(1 mg/kg,p.o.)and cryptotanshinone(10 and 20 mg/kg,i.p.)for four *** tests such as Morris water maze and elevated plus maze were conducted to check memory impairment caused by *** day 29,all rats were sacrificed,and the brains were separated for estimation of neuroinflammatory factors,biochemical parameters,neurotransmitters,Aβ(1-42),blood-brain barrier permeability,nuclear factor erythroid 2-related factor 2(Nrf2),and brain-derived neurotrophic factor(BdNF).Results:Treatment with cryptotanshinone dose-dependently enhanced spatial memory,improved the levels of neurotransmitter and antioxidant enzymes,and suppressed proinflammatory cytokine *** also decreased Aβ(1-42)accumulation and increased the levels of Nrf2 and BdNF in the ***,the histopathological results showed that cryptotanshinone reduced cladribine-induced neuronal death in the ***:Cryptotanshinone exhibits a promising neuroprotective effect against cladribine-induced cognitive impairment in preclinical studies,and may be a potential phytochemical for the treatment and management of cognitive impairment.

关键词： Alzheimer's disease Cladribine Cryptotanshinone Neurotransmitters Neuroprotective Proinflammatory cytokines Cognitive deficit

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Study of Nanodispersed Iron Oxides Produced in Steel drilling by Contracted Electric-Arc Air Plasma Torch

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Plasma Science and Technology 2008年第3期10卷 352-357页

作者： P.STEFANOV d.gALANOV g.VISSOKOV d.PANEVA B.KUNEV I.MITOV ISMA Ltd. Samokovsko Chaussee Str. 1738 Sofia Bulgaria Institute of Catalysis Bulgarian Academy of Sciences Sofia Bulgaria

The optimal conditions on the plasma-forming gas flowrate, discharge current and voltage, distance between the plasma-torch nozzle and the metal plate surface for the process of penetration in and vaporization of steel plates by the contracted electric-arc air plasma torch accompanied by water quenching, were determined. The X-ray structural and phase studies as well as Mossbauer and electron microscope studies on the samples treated were performed. It was demonstrated that the vaporized elemental iron was oxidized by the oxygen present in the air plasma jet to form iron oxides （wiistite, magnetite, hematite）, which, depending on their mass ra- tios, determined the color of the iron oxide pigments, namely, beginning from light yellow, through deep yellow, light brown, deep brown, violet, red-violet, to black. A high degree of dispersity of the iron oxides is thus produced, with an averaged diameter of the particles below 500 nm, and their defective crystal structure form the basis of their potential application as components of iron-containing catalysts and pigments.

关键词： nanodispersed iron oxides preparation plasma torch

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Positive MR and Large Temperature—Field Sensitivity in Manganite Based Heterostructures

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Journal of Materials Science & Technology 2013年第10期29卷 989-994页

作者： Uma Khachar P.S.Solanki R.J.Choudhary d.M.Phase d.g.Kuberkar department of Physics Saurashtra University UgCe-dAE Consortium for Scientifc Research

Studies on the ZnO/La0.5Pr0.2Sr0.3Mn03 （LPSMO）/SrNb0.002Ti0.99803 （SNTO） heterostructure having varying thickness of p-type LPSMO （100 nm - LP1） and （200 nm - LP2） manganite are carried out. ZnO/LPSMO （n-p） and LPSMO/SNTO （p-n） junctions of both the heterostructures exhibit good rectifying behavior in a wide range of temperature and applied field. Forward and reverse bias characteristics of both the junctions of heterostructures show opposite behavior. The observation of negative magnetoresistance （MR） at 5 K and positive MR at 300 K, in both the heterostructures, has been explained in the context of interface region effects and filling of energy bands of LPSMO manganite. Further, at high temperature, the heterostructures exhibit large temperature （46%K-1） and field （40%T-1） sensitivities. dependence of transport, magnetotransport, I-V and sensing properties of the heterostructures, on the temperature, field and film thicknesses have been discussed in this communication.

关键词： Interfaces Thin films Pulsed laser deposition X-ray diffraction Electric properties

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Parameter uncertainty in biomathematical model described by one-prey two-predator system with mutualism

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International Journal of Biomathematics 2017年第6期10卷 147-182页

作者： d. Pal g. S. Mahapatra g. P. Samanta Chandrahati dilip Kumar High School (HS) Chandrahati 712504 West Bengal India department of Mathematics National Institute of Technology-Puducherry Karaikal 609605 India department of Mathematics Indian Institute of Engineering Science and Technology Shibpur Howrah 711103 India

In this paper, a three-species system consisting of two predators which are in mutual- ism with each other and preying on the same single prey is considered. Also, the prey and first predator are harvested under optimal conditions. The values of the biological parameters depend on the collection of data from the experts as well as on the nature of the environment in which prey predator system are considered. So the biological para- meters are not precise in reality. This paper presents a different approach to study the prey-predator model with imprecise biological parameters. All the possible equilibrium points are identified and the local as well as global stability criteria under imprecise- ness are discussed. The possibility of existence of bionomic equilibrium is discussed. The optimal harvesting policy is studied using Pontryagin＇s maximum principle. Numerical examples are provided to support the proposed approach.

关键词： Mutualism equilibrium stability bioeconomic optimal control intervalnumber.

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Advancements in Liver Tumor detection:A Comprehensive Review of Various deep Learning Models

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 91-122页

作者： Shanmugasundaram Hariharan d.Anandan Murugaperumal Krishnamoorthy Vinay Kukreja Nitin goyal Shih-Yu Chen deptartment of Artificial Intelligence and data Science Vardhaman College of EngineeringHyderabad501218India deptartment of CSE V.S.B College of EngineeringKarur639111India deptartment of Electrical and Electronics Engineering Vardhaman College of EngineeringHyderabad501218India Centre for Research Impact&Outcome Chitkara UniversityRajpura140401PunjabIndia department of Computer Science and Engineering School of Engineering and TechnologyCentral University of HaryanaMahendergarh123031HaryanaIndia department of Computer Science and Information Engineering National Yunlin University of Science and TechnologyYunlin64002Taiwan Intelligence Recognition Industry Service Research Center National Yunlin University of Science and TechnologyYunlin64002Taiwan

Liver cancer remains a leading cause of mortality worldwide,and precise diagnostic tools are essential for effective treatment *** Tumors(LTs)vary significantly in size,shape,and location,and can present with tissues of similar intensities,making automatically segmenting and classifying LTs from abdominal tomography images crucial and *** review examines recent advancements in Liver Segmentation(LS)and Tumor Segmentation(TS)algorithms,highlighting their strengths and limitations regarding precision,automation,and *** metrics are utilized to assess key detection algorithms and analytical methods,emphasizing their effectiveness and relevance in clinical *** review also addresses ongoing challenges in liver tumor segmentation and identification,such as managing high variability in patient data and ensuring robustness across different imaging *** suggests directions for future research,with insights into technological advancements that can enhance surgical planning and diagnostic accuracy by comparing popular *** paper contributes to a comprehensive understanding of current liver tumor detection techniques,provides a roadmap for future innovations,and improves diagnostic and therapeutic outcomes for liver cancer by integrating recent progress with remaining challenges.

关键词： Liver tumor detection liver tumor segmentation image processing liver tumor diagnosis feature extraction tumor classification deep learning machine learning

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The Investigations into β-Cyclodextrinas HPLC Mobile Phase Chiral Additives　*** Adsorption of β-Cyclodextrin and Its Methylated derivative on an OdS Stationary Phase

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中国药科大学学报 1997年第1期 33-37页

作者：ＨｏｎｇｘｉＬＩＡＮＧＤ．Ｇ．ＤｕｒｈａｍＴｈｅＳｃｈｏｏｌｏｆＰｈａｒｍａｃｙＴｈｅＲｏｂｅｒｔＧｏｒｄｏｎＵｎｉｖｅｒｓｉｔｙＴｈｅＡｎａｌｙｔｉｃａｌ＆ＣｏｍｐｕｔｅｒＣｅｎｔｒｅＣｈｉｎａＰｈａｒｍａｃｅｕｔｉｃａｌＵｎｉｖｅｒｓｉｔｙ

通过ＨＰＬＣ结合旋光光度定量的方法，探讨了流动相添加剂β－环糊精及其２，６－二甲基衍生物的吸附性质。结果表明β－环糊精在ＯＤＳ固定相上不吸附，而其２，６－二甲基衍生物则呈典型的单分子层吸附。

关键词： β-环糊精吸附 OdS固定相手性流动相添加剂

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