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1.
DeterminationofStandardMolarEnthalpiesofFormationofComplexesofRareEarthBromideswithGlycineSunTongshan(孙同山),WangFenglian(王凤廉),...  相似文献   

2.
DeterminationofCrystalStructureofBritholite-YZhangJian-Hong;(张建洪);FangZe;(方泽);LiaoLi-Bing;(廖立兵)(ChinaUniversityofGeosciences,...  相似文献   

3.
Greatinteresthasbeenarousedinthestudyofcomplexesofrareearthsaltswithaminoacidsbecauserareearthionspossesssomespecialfunctionsinbiochemistry .Theycanbeusedasaprobetolabelthecalciumion .Moreover,aminoacidsarethestructureunitofproteins .Gaoandcoworkersrece…  相似文献   

4.
of tend     
《铁合金》2007,(4)
on transplant are as follows: autologous tendon, allogeneic tendon, artificial tendon and tissue engineered tendon. Recently, studies on allogeneic tendon are more and more favorable. In late 1980s, establishment and development of tissue engineering bring a new way for repairing de  相似文献   

5.
Muntin  A. V.  Sevidov  A. E.  Tikhonov  S. M.  Ionov  S. M.  Zinoviev  A. V.  Labyshkina  T. A. 《Metallurgist》2021,65(3-4):305-313
Metallurgist - We present the analysis of the mechanism of in-service wear of the working rolls of wide-band rolling mills on an example of a 1950 mill from the casting-rolling complex of the...  相似文献   

6.
InvestigationofCrystallizationIncorporationofEr-implantedSiliconWanYa(万亚);LiDaiqing(李岱青)(DepartmentofChemistry,YantaiTeachers...  相似文献   

7.
In 192 2 ,AmericanMeehanappliedthefirstpatentforinoculatedcastiron .Nowtherearemorethan 10 0 0kindsofinoculantsintheworld .Thein oculationmeansthatsomematerialisputintomeltedirontocausesome physicalandchemicalchangeswhicharedifferentfromthosecausedbythealloyingelementinthecastiron .Intheearlydays ,themaincontentofinoculantwassilicon ,andsoonafterwardscalcium ,aluminium ,barium ,strontiumandmanga nese ,etcwereincluded .In 196 1,ceriumwasintro ducedintoinoculant .Nowtheinoculantsarewidelyappli…  相似文献   

8.
Influence of Light Rare Earth on Toughness of Welded Seam of LAHS Steel   总被引:1,自引:0,他引:1  
The influence mechanism of light rare earth elements, which are transited to the welding seam of low-alloy high strength (LAHS) steel through the covering of the electrode, on the toughness of the welding seam was studied. The experimental results show that proper amount of rare earth elements can desulfurate, dehydrogenate, reduce inclusions and purify the structure of the welding seam. Rare earth element additions have .the effect on welding seam and, at the same time, the transformation of side-batten ferrite is resisted while the pin-ferrite structure is promoted. The improvement of the toughness of the welding seam is due to the purifying action of rare earth elements as well as their refining effect on the structure. However, the toughness of the welding seam can decrease when the amount of light rare earth elements are added excessively because the crystal grains become coarser, porosities appear and the inclusions increase as well. The experimental results show that the suitable amount of light rare earth element additions is about 2%.  相似文献   

9.
Based on the thermodynamical principle the new formula for calculation of heat of fusion and its error havebeen derived from binary phase diagrams which could be classified to eutectic,solid solution,degenerate eutecticand involving a compound phase diagram and so on.Using these formulae heats of fusion of some rare earth ox-ides have been predicted.  相似文献   

10.
The adsorption-desorption behavior of the mixed rare earth elements(RE)on the main types ofsoils of China,kaolinite and synthetic oxides was studied.The isothermal adsorption of RE was fitted toLangmuir.Freundlich and Temkin equations.The main factors determining the RE adsorption capacity ofthe soils are the type of clay mineral and the content of amorphous iron oxide in the soils.The above two fac-tors and the pH of soil determine the RE adsorption ability of the soils.The soil and synthetic iron,manga-nese oxides strongly adsorb RE specifically.  相似文献   

11.
Conclusions We examined the behavior of two materials during high-temperature oxidation: the singlephase -sialon and the material based on -sialon containing up to 8% residual -Si3N4 and the glass phase produced by reaction sintering of the charge based on -modification of silicon nitride. The results show that the maximum oxidation resistance in the temperature range 800–1300°C is exhibited by the single-phase -sialon Si5.5Al0.5O0.5N7.5. The oxidation resistance decreases in the presence of the residual -Si3N4 and the glass phase in the material. The oxidation kinetics are also determined by the structure and composition of the oxide film. The kinetic curves are governed by a parabolic law which indicates that oxidation of the sialons is limited by the diffusion processes. No marked changes were detected in the lattice spacing of the sialon after oxidation.Translated from Poroshkovaya Metallurgiya, No. 6(306), pp. 69–73, June, 1988.  相似文献   

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13.
Effect of Cerium on the Viscosity of Liquid Fe-C Alloy of Eutectic Content   总被引:1,自引:0,他引:1  
The viscosities of liquid Fe-4.30C and Fe-4.30C-Ce alloys were measured by oscillating crucible viscometer. The results show that viscosity of Fe-4.30C alloy changes from 5.50 to 8.30 MPa~s when the liquid is cooled from 1425℃ to the melting point. The abnormity of viscosity of Fe-4.30C alloy near the melting point is reasonable due to the formation of graphite. The addition of cerium especially with content higher than 0.21% causes an evidently decrease in viscosity for eutectic alloy resulting from increase of free volume and size decrease of atom cluster in the liquids. It can be concended that the existence of C-Ce compound contributes to the discontinuous of viscosity at 1340 ~ 1370 ℃ for the Fe-4.30C-Ce alloy by experinments with differential scanning calorimeter.  相似文献   

14.
Nanocompositemagnetsareoneofcandidatesformagnetsinthenextgeneration .Inananocompositemagnet,theexistenceofmagneticallysoftgrainswithahighsaturationmagnetizationenhancestherema nence,andconsequentlyahigh (BH ) max valueisachieved[1] .Asthemagnetizationinthesoftgrainsispreventedfromtheirreversalbytheintergrainex changeinteractionbetweensoftandhardgrains ,theintergrainexchangeinteractionplaysanimportantroleindeterminingmagneticproperties .Therefore ,itscontrolisconsideredtobeakeytechnologyforobt…  相似文献   

15.
正In March 2006,Henan Luanchuan County was awarded"China’s Capital of Molybdenum"honorable title by the China Mining Association.In the following decade,Luanchuan County rose to instant fame in China with the reputation of"China’s Capital of Molybdenum",then,how did"China’s Capital of Molybdenum"forge its glory?  相似文献   

16.
The tribological properties of ceramic composites of the system TiN?AlN are studied in the concentration range 10–90% AlN. It was found that materials which contain 25, 50, and 75% AlN have a low friction coefficient. Their rate of wear when paired with steel is neglible—2.9–6.0 μm/km (the wear rate of a steel-steel 024 couple is 1000 μm/km). Thin oxide films are formed during friction at high velocities and pressures. These films have relatively high adhesion with respect to materials of the TiN?AlN system and relatively low adhesion with respect to steel. The films may act as a solid lubricant, thus reducing the friction coefficient and wear. This is particularly true of the materials 25% TiN?75% AlN and 50% TiN?50% AlN.  相似文献   

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The main bibliographic impact factors of ARCHIVOS DE BRONCONEUMOLOGIA for the past two years are estimated. Citations of ARCHIVOS DE BRONCONEUMOLOGIA in 1996 and 1997 by Medicina Clínica and all citing journals grouped under the heading "Respiratory System" in the Science Citation Index were counted. The year the citation appeared and the year of publication of the article in ARCHIVOS DE BRONCONEUMOLOGIA were recorded. The total number of articles published by ARCHIVOS DE BRONCONEUMOLOGIA between 1994 and 1996 were also counted. Based on these data we calculated our journal's impact factor for each year studied. Relative impact factor was also figured. In 1996 the exposure factor achieved was 1.602, the half-life of articles was 2.00 years, the impact factor was 0.069 and the relative impact factor was 1.371. In 1997 the exposure index was 1.477, the citation half-life was 3.00 years and the impact factor was 0.030. In conclusion, the international impact of ARCHIVOS DE BRONCONEUMOLOGIA is modest, although our relative impact factor is greater than that of some other internal medicine publications or specialized journals listed in Journal Citation Reports.  相似文献   

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