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graphite-like and diamond-like Carbon Coatings with Exceptional Tribological Properties

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材料热处理学报 2004年第05B期25卷 796-802页

作者： m. Jarratt S. K. Field d.g. Teer Teer Coatings Ltd. West Stone House West Stone Berry Hill Industrial Estate Droitwich WR9 9AS UKTeer Coatings Ltd. West Stone House West Stone Berry Hill Industrial Estate Droitwich WR9 9AS UKTeer Coatings Ltd. West Stone House West Stone Berry Hill Industrial Estate Droitwich WR9 9AS UK

Two hard, carbon-based solid lubricant coatings, graphit-iC? and dymon-iC?, have been developed that offer considerable benefits for industry. Both of these new coatings have a high tribological load-bearing capacity, exceptional wear resistance and very low friction, even in dry or lubricant-starved contact. This is in contrast to many commercial diamond-like carbon, dLC coatings, which tend to be highly stressed and therefore brittle, making them unsuitable for high load bearing industrial applications. The development of the new solid lubricant coatings is described, and details of their tribological performance in dry, water and oil-lubricated environments are given. The structure of the coatings has been investigated and related to the tribological properties, and the mechanism for the low friction and wear rates is discussed. The coatings have been used to successfully improve the lifetime and efficiency of many highly loaded mechanical parts, including automotive fuel injection components, gears, bearings, tappets (cam followers), gudgeon (wrist) pins, etc. They also offer benefits for tooling and are widely used in forming or machining of non-ferrous alloys, and extensively on dies and moulds. Other industrial application areas include electrical devices that require either high conductivity or insulation, optical devices requiring abrasion resistance and surgical tools and implants.

关键词： dLC 摩擦力碳覆层固体润滑剂

SCIENTIFIC PRINCIPLES FOR mOdIFICATION OF WATER-SOLUBLE POLYmERS. FORmATION OF mACROmOLECULAR COmPLEXES

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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

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

Regression analysis of squeezing-induced hybrid nanofluid flow in darcy-Forchheimer porous medium

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 193-208页

作者： K.mUHAmmAd m.SARFRAZ department of Humanities and Sciences School of Electrical Engineering and Computer Science National University of Sciences and Technology department of mathematics Quaid-i-Azam University

This article presents a mathematical model addressing a scenario involving a hybrid nanofluid flow between two infinite parallel plates. One plate remains stationary, while the other moves downward at a squeezing velocity. The space between these plates contains a darcy-Forchheimer porous medium. A mixture of water-based fluid with gold(Au) and silicon dioxide(Si O2) nanoparticles is formulated. In contrast to the conventional Fourier's heat flux equation, this study employs the Cattaneo-Christov heat flux equation. A uniform magnetic field is applied perpendicular to the flow direction, invoking magnetohydrodynamic(mHd) effects. Further, the model accounts for Joule heating, which is the heat generated when an electric current passes through the fluid. The problem is solved via NdSolve in mATHEmATICA. Numerical and statistical analyses are conducted to provide insights into the behavior of the nanomaterials between the parallel plates with respect to the flow, energy transport, and skin *** findings of this study have potential applications in enhancing cooling systems and optimizing thermal management strategies. It is observed that the squeezing motion generates additional pressure gradients within the fluid, which enhances the flow rate but reduces the frictional drag. Consequently, the fluid is pushed more vigorously between the plates, increasing the flow velocity. As the fluid experiences higher flow rates due to the increased squeezing effect, it spends less time in the region between the plates. The thermal relaxation, however, abruptly changes the temperature, leading to a decrease in the temperature fluctuations.

关键词： Nanofluidics

Effect of Yttrium Addition on microstructural Characteristics and Superplastic Behavior of Friction Stir Processed ZK60 Alloy

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Journal of materials Science & Technology 2013年第12期29卷 1116-1122页

作者： Z.A.Luo g.m.Xie Z.Y.ma g.L.Wang g.d.Wang State Key Laboratory of Rolling and Automation Northeastern University Shenyang National Laboratory for materials Science Institute of Metal ResearchChinese Academy of Sciences

As-extruded ZK60 and ZK60-Y magnesium alloy plates were successfully processed via friction stir processing （FSP） at a tool rotation rate of 1600 r/rain and a traverse speed of 200 mm/min. FSP resulted in the formation of equiaxed recrystallized microstructures with the average grain sizes of ,-8.5 and -4.7 μm in the ZK60 and ZK60-Y alloys, respectively. moreover, FSP broke and dispersed the mgZn2 and W-phase （mg3Zn3Y2） particles and dissolved mgZn2 phase in the FSP ZK60 alloy. With the addition of rare earth element yttrium （Y） into the ZK60 alloy, the ratio of the high angle grain boundaries （HAgBs） in the FSP alloys increased from 64% to 90%, and a certain amount of twins appeared in the FSP ZK60-Y alloy. The maximum elongation of 1200% and optimum strain rate of 3 X 10-3 s-1 achieved at 450 °C in the FSP ZK60-Y alloy were substantially higher than those of the FSP ZK60 alloy. This is attributed to the fine grains with high ratio of HAgBs and the distribution of a large number of dispersed second phase particles with high thermal stability in the FSP ZK60-Y alloy. grain boundary sliding was identified as the primary deformation mechanism in the FSP ZK60 and ZK60-Y alloys from the superplastic data analyses and surficial morphology observations.

关键词： magnesium alloy Friction stir processing Rare earth element microstructure Superplasticity

An unusual cause of cholecystitis:Heterotopic pancreatic tissue in the gallbladder

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World Journal of gastroenterology 2007年第2期13卷 313-315页

作者： glsm zlem Elpek Sevgi Bozova gkben Y■d■r■m Kpesiz mehmet ■■ Akdeniz University Medical School Department of Pathology Yeni T■p Dekanl■k 07070 Antalya Turkey Akdeniz University Medical School Department of General Surgery Yeni T■p Dekanl■k 07070 Antalya Turkey

gallbladder localization of heterotopic pancreas （HP） is uncommon and very rarely gives rise to symptoms. Herein we report a case of HP found in the gallbladder neck presented with signs and symptoms of cholecystitis. The patient was a 40-year old male, suffering from epigastric pain, abdominal fullness and fever. On physical examination, the right upper abdomen was tender with a positive murphy＇s sign. Ultrasonographic examination showed a hydropic gallbladder without stones and he underwent a cholecystectomy. Pathological examination revealed an intramural nodule （9 ram） in the neck region which is consisted of acini, ducts and islet cells of an aberrant pancreatic tissue. Although HP is encountered rarely in the gallbladder and is found incidentally during pathological studies, this case emphasizes that HP might cause symptoms and present clinically as cholecystitis. For this reason, in patients presenting with symptomatic gallbladder diseases, including cholecystitis without any other pathology, HP should be taken into consideration before it is diagnosed as ＂idiopathic＇：

关键词： Heterotopic tissues Pancreas Acalculous cholecystitis gallbladder

Passive electrochemical hydrogen recombiner for hydrogen safety systems:prospects

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Nuclear Science and Techniques 2023年第6期34卷 215-224页

作者： A.V.Avdeenkov d.g.Bessarabov d.g.Zaryugin All Russian Research Institute for Nuclear Power Plants Operation JSC 25 Ferganskaya Str.MoscowRussia109507 HySA Center Faculty of EngineeringNorth-West UniversityPotchefstroom2520South Africa State Atomic Energy Corporation Rosatom 24 Bolshaya Ordynka Str.MoscowRussia119017

This paper presents the concept of a passive electrochemical hydrogen recombiner(PEHR).The reaction energy of the recombination of hydrogen and oxygen is used as a source of electrical energy according to the operating principle for hydrogen fuel cells to establish forced circulation of the hydrogen mixture as an alternative to natural circulation(as is not utilized in conventional passive autocatalytic hydrogen recombiners currently used in nuclear power plants(NPPs)).The proposed concept of applying the physical operation principles of a PEHR based on a fuel cell simultaneously increases both productivity in terms of recombined hydrogen and the concentration threshold of flameless operation(the‘ignition’limit).Thus,it is possible to reliably ensure the hydrogen explosion safety of NPPs under all conditions,including beyond-design *** experimental setup was assembled to test a laboratory sample of a membrane electrode assembly(mEA)at various hydrogen concentrations near the catalytic surfaces of the electrodes,and the corresponding current–voltage characteristics were *** simplest mEA based on the Advent P1100W PBI membrane demonstrated stable performance(delivery of electrical power)over a wide range of hydrogen concentrations.

关键词： Recombiner Catalytic ignition Hydrogen explosion safety Hydrogen fuel cell membrane electrode assembly

Intensity of parasitic infestation in silver carp,Hypophthalmichthys molitrix

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第12期13卷 1024-1028页

作者： m.m.ALAm m.A.KHAN m.A.HUSSAIN d.mOUmITA A.g.mAZLAN K.d.SImON department of Fisheries University of RajshahiRajshahi 6205Bangladesh School of Environmental and Natural Resource Sciences Faculty of Science and TechnologyUniversiti Kebangsaan Malaysia43600 UKM BangiSelangorD.E.Malaysia

Silver carp,Hypopthalmichthys molitrix is one of the most economically valuable fish species in ***,its production is often hindered by parasite-induced *** present study reports the intensity of parasitic infestation in 216 specimens of *** collected from different fish markets in Rajshahi City,*** different parasite species (Trichodina pediculatus,dactylogyrus vastator,Ichthyophthirius multifilis,gyrodactylus elegans,Lernaea sp.,Apiosoma sp.,myxobolus rohitae,Camallanus ophiocephali,and Pallisentis ophiocephali) were recovered from the gill,skin,stomach,and intestine of host *** highest level of infection was observed for host skin,while lower levels were observed for host gill,stomach,and *** results also revealed that the intensity of parasite infection in different organs of *** varied with the *** particular,the highest levels of infection were recorded during the winter period (November-February),when fish are most susceptible to *** findings of the study will help in the management and conservation of ***.

关键词： Freshwater fish disease Parasites Carpfishery Infestation Aquaculture Bangladesh

Effect of Sodium metasilicate on Structural, Optical, dielectric and mechanical Properties of AdP Crystal

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Journal of materials Science & Technology 2016年第1期32卷 62-67页

作者： mohd Anis m.d. Shirsat S.S. Hussaini B.Joshi g.g. muley department of Physics Sant Gadge Baba Amravati University Amravati 444602 Maharashtra India Crystal growth Laboratory Department of Physics MiUiya Arts Science and Management Science College Beed 431122 Maharashtra India Intelligent materials Research Laboratory Department of Physics Dr. Babasaheb Ambedkar Marathwada University Aurangabad 431005 Maharashtra India Science and Engineering Research Board New Delhi 110016 India

For the first time, sodium metasilicate （SmS） doped ammonium dihydrogen phosphate （AdP） crystal was grown by slow evaporation solution technique. The unit cell parameters of grown crystal were deter- mined by means of single crystal X-ray diffraction technique. The qualitative analysis of SmS doped AdP crystal was carried out using energy dispersive X-ray and Fourier transform infrared analysis. The in- crease in optical transparency of doped AdP crystal was ascertained in the range of 200-900 nm using the UV-visible spectral analysis. The vital optical constants were evaluated using the transmittance data to explore various optical device applications of crystal. The assertive influence of SmS on mechanical and dielectric behavior of AdP crystal was investigated by means of Vickers microhardness analysis and dielectric studies, respectively. The enhancement in second harmonic generation （SHg） efficiency of SmS doped AdP crystal with reference to potassium dihydrogen phosphate （KdP） and AdP was confirmed from Kurtz-Perry SHg test. The Kerr lensing nonlinearity in SmS doped AdP crystal was identified by means of Z-scan analysis and the third order nonlinear optical susceptibility （χ3） was found to be 6.19 × 10-5 esu, which vitalizes its application for laser stabilization systems.

关键词： Crystal growth Nonlinear optical materials dielectric properties Optical properties