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Comparative studies on Y(Ⅲ)and Dy(Ⅲ)extraction from hydrochloric and nitric acids by Cyanex 572 as a novel extractant

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Journal of Rare Earths 2018年第12期36卷 1342-1350页

作者： n.E.El-hefny M.S.Gasser sh.sh.Emam W.h.Mahmoud h.F.Aly hot Laboratories Centre Atomic Energy Authority Faculty of Science Ain Shams University

Extraction of Y(III) and Dy(III) from hydrochloric and nitric acids by Cy-572 in kerosene was studied. The factors affecting the extraction were separately investigated. The stoichiometry of the extracted species was deduced on the basis of slope analysis method. Evaluation of extraction equilibrium and stripping investigation was studied as well as saponification effect of Cy-572. The composition of the extracted metal species in the organic phase was found to be [MA·(hA)] for Y(III) or Dy(III) in both media.1.0 mol/L hCI is the best stripping agent for each metal ion from the studied acidic media in one *** Cy-572 does not exhibit any selectivity towards the extraction of Y(III) or Dy(III) from both hCI and hnOsolutions. Based on the obtained results, the data were compared and the separation feasibility between lanthanides and Y(III) in the two media was discussed.

关键词： Extraction Cyanex-572 Yttrium Lanthanides Separation factor Saponification

Experimental and numerical study on plasma nitriding of AISI P20 mold steel

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International Journal of Minerals,Metallurgy and Materials 2016年第9期23卷 1065-1075页

作者： n.nayebpashaee h.Vafaeenezhad sh.Kheirandish M.Soltanieh Materials Processing Simulation Laboratory(MPS-LAB) School of Materials and Metallurgical EngineeringIran University of Science and Technology(IUST) School of Materials and Metallurgical Engineering Iran University of Science and Technology(IUST)

In this study, plasma nitriding was used to fabricate a hard protective layer on AISI P20 steel, at three process temperatures（450℃, 500℃, and 550℃） and over a range of time periods（2.5, 5, 7.5, and 10 h）, and at a fixed gas n2：h2 ratio of 75vol%：25vol%. The morphology of samples was studied using optical microscopy and scanning electron microscopy, and the formed phase of each sample was determined by X-ray diffraction. The elemental depth profile was measured by energy dispersive X-ray spectroscopy, wavelength dispersive spectroscopy, and glow dispersive spectroscopy. The hardness profile of the samples was identified, and the microhardness profile from the surface to the sample center was recorded. The results show that ε-nitride is the dominant species after carrying out plasma nitriding in all strategies and that the plasma nitriding process improves the hardness up to more than three times. It is found that as the time and temperature of the process increase, the hardness and hardness depth of the diffusion zone considerably increase. Furthermore, artificial neural networks were used to predict the effects of operational parameters on the mechanical properties of plastic mold steel. The plasma temperature, running time of imposition, and target distance to the sample surface were all used as network inputs; Vickers hardness measurements were given as the output of the model. The model accurately reproduced the experimental outcomes under different operational conditions; therefore, it can be used in the effective simulation of the plasma nitriding process in AISI P20 steel.

关键词： tool steel plasma nitriding sputtering neural networks

Silk-based nerve guidance conduits with macroscopic holes modulate the vascularization of regenerating rat sciatic nerve

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neural Regeneration Research 2025年第6期20卷 1789-1800页

作者： Carina hromada Patrick heimel Markus Kerbl LászlóGál Sylvia nürnberger Barbara Schaedl James Ferguson nicole Swiadek Xavier Monforte Johannes C.heinzel Antal nógrádi Andreas h.Teuschl-Woller David hercher Department Life Science Engineering University of Applied Sciences Technikum WienViennaAustria Austrian Cluster for Tissue Regeneration ViennaAustria Ludwig Boltzmann Institute for Traumatology The Research Center in Cooperation with AUVAViennaAustria University Clinic of Dentistry Medical University of ViennaViennaAustria Department of Plastic Reconstructive and Aesthetic SurgeryLandesklinikum Wiener Neustadt2700 Wiener NeustadtAustria Department of Anatomy Histology and EmbryologyAlbert Szent-Györgyi Medical SchoolUniversity of SzegedSzegedHungary Medical University of Vienna Department of Orthopedics and Trauma SurgeryDevision of Trauma SurgeryViennaAustria Department of hand- PlasticReconstructive and Burn SurgeryBG Unfallklinik TuebingenUniversity of TuebingenTuebingenGermany

Peripheral nerve injuries induce a severe motor and sensory deficit. Since the availability of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the use of tubular nerve guidance conduits(tnGCs). however, the use of tnGCs results in poor functional recovery and central necrosis of the regenerating tissue, which limits their application to short nerve lesion defects(typically shorter than 3 cm). Given the importance of vascularization in nerve regeneration, we hypothesized that enabling the growth of blood vessels from the surrounding tissue into the regenerating nerve within the tnGC would help eliminate necrotic processes and lead to improved regeneration. In this study, we reported the application of macroscopic holes into the tubular walls of silk-based tnGCs and compared the various features of these improved silk^(+) tnGCs with the tubes without holes(silk^(–) tnGCs) and autologous nerve transplants in an 8-mm sciatic nerve defect in rats. Using a combination of micro-computed tomography and histological analyses, we were able to prove that the use of silk^(+) tnGCs induced the growth of blood vessels from the adjacent tissue to the intraluminal neovascular formation. A significantly higher number of blood vessels in the silk^(+) group was found compared with autologous nerve transplants and silk^(–), accompanied by improved axon regeneration at the distal coaptation point compared with the silk^(–) tnGCs at 7 weeks postoperatively. In the 15-mm(critical size) sciatic nerve defect model, we again observed a distinct ingrowth of blood vessels through the tubular walls of silk^(+) tnGCs, but without improved functional recovery at 12 weeks postoperatively. Our data proves that macroporous tnGCs increase the vascular supply of regenerating nerves and facilitate improved axonal regeneration in a short-defect model but not in a critical-size defect model. This study suggests that further optimizatio

关键词： axon regeneration blood vessel functional recovery macroporous nerve lesion peripheral nerve repair sciatic nerve silk-based nerve guidance conduit vascularization

Green ionic metal-organic frameworks as nanocatalysts for CO_(2)fixation

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nano Research 2025年第1期18卷 260-269页

作者： nuria Martín Miguel Maireles-Porcar Julián Sánchez Velandia Belén Altava Francisco G.Cirujano Eduardo García-Verdugo Departamento de Química Inorgánica y Orgánica Universidad Jaume IAv.Sos Baynats/nCastellóde la PlanaCastellón 12071Spain

Co,ni,and Zn iso-reticular coordination polymers of 2,5-dihydroxyterphthalic acid(h_(2)dot)can be rapidly obtained under room temperature and aqueous conditions using either sodium or ammonium hydroxide as the bases to deprotonate the *** use of metal bromides and tetrabutylammonium hydroxide(TBAOh)as the base allows the green synthesis of ionic metal-organic frameworks(MOFs),characterized by X-ray diffraction(XRD),Fourier transform infrared(FTIR),scanning electron microscopy(SEM),thermo gravimetric analysis(TGA),h-nuclear magnetic resonance(nMR),elemental analysis,and X-ray photoelectron spectroscopy(XPS),and employed in the pressure,solvent,and additive-free CO_(2)fixation to epoxides by its cycloaddition to epichlorohydrin,exhibiting a cooperative behavior between the MOF and the ionic liquid formed within the framework,achieving TOns of the confined tetrabutylammonium bromide(TBABr)up to 700.

关键词： metal-organic frameworks(MOFs) ionic liquids heterogeneous catalysis CO_(2)conversion

Effects of Charge Inheritance on high Zn-Al Based Alloy

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Journal of Materials Science & Technology 1995年第2期11卷 153-156页

作者： GEnG, h MA, JJ YAnG, sh sh.ndong Polytechnic Univ Jinan China

The effects of several kinds of charges on microstructure and mechanical properties of ZA27 zinc alloy have been studied. Experimental results show that a certain amount of the mechining charge, granular charge and remelting charge treated in suitable way can increase greatly the mechanical properties of ZA27 alloy. It is thought that the charges possess microstructure inheritance to ZA27 alloy, so cause the property changes according to the viewpoints of casting alloy inheritance.

关键词： Zinc alloys

Sliding Wear Behavior of a Grey Cast Iron Surface Remelted by TIG

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Journal of Materials Science & Technology 2009年第5期25卷 622-628页

作者： h.Mohamadzadeh h.Saghafian sh.Kheirandish Department of Metallurgy and Materials Engineering Iran University of Science and TechnologyTehranIran

The sliding wear behavior of a grey cast iron surface remelted by tungsten inert gas （TIG） was studied and compared with the unremelted one in the current work. To evaluate the wear behavior a Pin-on-Disk wear test machine was used. Pins which were prepared from the samples with the remelted layers of different thicknesses of 1.2, 1.8, 2.5 and 3 turn were worn on an AISID3 steel counterface having a hardness of 63hRC under the applied loads of 54, 76 and gg n at a constant sliding velocity of 0.45 m/s. Scanning electron microscopy （SEM） equipped with energy dispersive X-ray analysis （EDS） and X-ray diffraction （XRD） techniques were used to characterize worn surface and subsurface and also wear debris obtained from the wear tests under different test conditions. Results showed that surface remelted grey cast iron have better wear properties for all applied normal loads in comparison with unremelted ones. Microscopic studies on the worn surfaces and subsurfaces of samples revealed that dominant wear mechanism for surface remelted samples was mild oxidative, while it was severe for unremelted samples. Increasing remelted layer thickness and then forming grosser microstructure lead to a decline of wear properties, whereas lower thickness of remelted layer with finer microstructure due to having higher cooling rate through remelting process can withstand better against wear.

关键词： Grey cast Iron Surface remelted Tungsten inert gas (TIG) Wear

Dry Sliding Oxidative Wear in Plain Carbon Dual Phase Steel

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Journal of Iron and Steel Research International 2007年第4期14卷 43-48页

作者： V Abouei h Saghafian sh Kheirandish Department of Metallurgy and Materials Engineering Iran University of Science and TechnologyNarmak 16844TehranIran

To investigate the tribological potential of the dual phase （DP） steel as a wear resistant material, the wear and the friction characteristics of this steel, which consists of hard martensite islands embedded in a ductile ferrite matrix, have been investigated and compared with those observed in plain carbon hardened （h） steel that has the same carbon content of 0.2%. Dry sliding wear tests have been carried out using a pin-on-disk wear testing machine at different normal loads of 21.3 n, 28. 5 n, 35.7 n, and 42.6 n and at a constant sliding velocity of 1.20 m/s. The analysis of surface and wear debris of samples showed that the wear mechanism was mainly mild oxidative. The friction and the wear rate of the h steel and the DP Steel have been explained with respect to the microstructure and the wear mechanism.

关键词： dual phase steel wear microstructure heat treatment

Evaluation of Four Coals for Blast Furnace Pulverized Coal Injection

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Journal of Iron and Steel Research International 2010年第3期17卷 8-12,20页

作者： sh Raygan h Abdizadeh A Eskandari Rizi School of Metallurgy and Materials Engineering University of Tehran

One of the effective methods of reducing coke consumption is pulverized coal injection. The most important problems encountered in this method are reduced permeability, unburned and high ash content. To select the best coal for injection, suitable tests can be used. Therefore, experiments such as proximate and ultimate analysis, Rock- Eval and combustion tests were performed on four kinds of coals from different mines, including Sarakhs, Sangrood, Karmozd, and Tabas. The results of proximate and ultimate analysis indicated that although the sulfur content and ash content of selected coals were a little high, they were suitable for coal injection. The results of combustion experiments and Rock-Eval tests showed that Karmozd coal was the best one to be injected into blast furnace. The result indicated that the mixing of coals could improve the combustion properties of pulverized coals.

关键词： pulverized coal blast furnace non-coking coal

Effects of Silicon Content and Intercritical Annealing on Manganese Partitioning in Dual Phase Steels

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Journal of Iron and Steel Research International 2010年第5期17卷 44-50页

作者： A nouri h Saghafian sh Kheirandish Department of Metallurgy and Materials Engineering Iran University of Science and Technology

Steels of constant manganese and carbon contents with silicon content of 0.34 %- 2.26% were cast. The as-cast steels were then hot rolled at 1 100 ℃ in five passes to reduce the cast ingot thickness from 80 to 4 mm, air cooled to room temperature and cold rolled to 2 mm in thickness. Dual phase microstructures with different volume fraction of martensite were obtained through the intercritical annealing of the steels at different temperatures for 15 min followed by water quenching. In addition to intercritical annealing temperature, silicon content also altered the volume fraction of martensite in dual phase steels. The partitioning of manganese in dual phase silicon steels was investigated using energy-dispersive spectrometer （EDS）. The partitioning coefficient, defined as the ratio of the amounts of alloying element in the austenite to that in the adjacent ferrite, for manganese increased with increasing intercritieal annealing temperature and silicon content of steels. It was also found that the solubility of manganese in ferrite and austenite decreased with increasing intereritical temperature. The results were discussed by the diffusivity and the solubility of manganese in ferrite and austenite existed in dual phase silicon steels.

关键词： partitioning dual phase steel intercritical annealing temperature silicon manganese