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Oxidation,Mechanical and Tribological Behaviors of the Ni/cBN Abrasive coating-coated Titanium Alloys

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Acta Metallurgica Sinica(English Letters) 2021年第7期34卷 1007-1020页

作者： Y.D.Liu j.H.Liu w.S.Gu H.L.Li w.H.Li Z.L.Pei j.Gong c.Sun School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

In order to improve the oxidation and wear resistance of blades tip of titanium alloys as well as the sealing performance of the gas turbine engine,a Ni/cBN abrasive coating was prepared on titanium alloys through composite ***,mechanical and tribological properties of the abrasive coating were ***,the effect of the oxidation on the mechanical and tribological properties was also *** results revealed that the abrasive coating underwent slight oxidation within 700℃.Meanwhile,some intermetallic compounds,Ni3Ti,NiTi and NiTi2,were formed at the coating/substrate interface during *** to the pinning effect of cBN particles and the different thermal expansion coefficients of the coating and substrate,the coating/substrate interface was cracked after oxidation at 700℃.Tensile results showed that the presence of coating reduced the strength of the alloy significantly at room temperature,while only marginal variations of the strength of the coated and uncoated specimens at elevated ***,the wear tests indicated that the coating had the excellent cutting ability and wear resistance,which can effectively protect the blades tip of titanium *** the temperature increased,the wear resistance decreased due to the decrease in the mechanical properties of the Ni/cBN coating.

关键词： Abrasive coating Oxidation Mechanical properties wear Titanium alloy

Bo′s abdominal acupuncture improves disordered metabolism in obese type 2 diabetic rats through regulating fibroblast growth factor 21 and its related adipokines

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journal of Traditional chinese Medicine 2023年第6期43卷 1200-1208页

作者： QIN Xihui pang jianli XIONG Guan FENG jie School of Pharmaceutical Sciences Guangxi Medical UniversityNanning 530021China Department of Endocrinology Ruikang Hospital Affiliated to Guangxi University of Traditional Chinese MedicineNanning 530011China Department of Gynecology and obstetrics the Eighth People’s Hospital of NanningNanning 530007China

OBjEcTIVE:To investigate the effect of Bo′s abdominal acupuncture(BOAA)on fibroblast growth factor 21(FGF21)and its related adipokines in type 2 diabetes mellitus(T2DM)***:This study established obese T2DM rat model by high-fat diet(HFD)with a dose of streptozotocin(STZ,30 mg/kg).Obese T2DM rats were randomly subdivided into four groups(n=10):negative,BOAA,conventional acupuncture(cOA group)and metformin group(Met group)*** biochemical parameters,mRNAs,and proteins were analyzed using enzyme-lined immunoassays kits,quantitative polymerase chain reaction and western ***:Treatment with BOAA attenuated the histopathological changes in visceral fat and restored the alterations in the levels of body weight,fasting blood glucose(FBG),homeostasis model assessment for insulin resistance(HOMA-IR).BOAA treatment significantly decreased the levels of triglyceride,total cholesterol,low density lipoprotein cholesterol,leptin,and increased the serum levels of high-density lipoprotein cholesterol,fibroblast growth factor 21(FGF21),adiponectin(ADP),peroxisome proliferator-activated receptorγ(PPAR-γ),c-peptide(c-P)in obese T2DM ***,BOAA treatment significantly increased the mRNA expressions of FGF21,ADP,leptin,PPAR-γ,PPAR-αand adenosine 5‘-monophosphate(AMP)-activated protein kinase(AMPK).Besides,BOAA treatment upregulated the protein expressions of fibroblast growth factor receptors3(FGFR3),PPAR-α,extracellular signal-regulated kinase(ERK),phosphorylated ERK(p-ERK),AMPK,p-AMPK,Liver kinase B1(LKB1),phosphorylated LKB1(p-LKB1),acetyl-coA carboxylase(Acc)and phosphorylated Acc(p-Acc),while downregulated the protein expressions of FGF21 and PPAR-γin visceral ***:BOAA treatment reduced FBG and body weight,and improved insulin sensitivity through regulating FGF21 signaling pathway and its related adipokine in obese T2DM rats.

关键词： diabetes mellitus type 2 obesity fibroblast growth factors adipokines insulin resistance Bo′s abdominal acupuncture

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Microstructure and Properties of wB_(2)/cr Multilayer Films with Different Bilayer Numbers Deposited by Magnetron Sputtering

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Acta Metallurgica Sinica(English Letters) 2022年第4期35卷 693-702页

作者： w.B.Shi Y.M.Liu w.H.Li T.Li H.Lei j.Gong c.Sun Shi-changxu Innovation center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China college of Materials Science and Engineering Xi'an Shiyou UniversityXi'an 710065China

The influence of the bilayer number on the microstructure,mechanical properties,adhesion strength and tribological behaviors of the wB_(2)/cr multilayer films was systematically investigated in the present *** groups of wB_(2)/cr films with the same modulation ratio were synthesized by magnetron sputtering *** crystalline structure of the films was determined by X-ray *** morphologies and the microstructure of the films were observed by scanning electron microscopy,atomic force microscopy and transmission electron ***,Nano indenter,scratch tester and ball-on-disc tribometer were used to evaluate the mechanical and tribological *** bilayer numbers varied from 5 to 40,the hardness increased first and then decreased with the maximum hardness of 33.9 GPa when the bilayer number is *** H/E^(*)and H^(3)/E^(*2)values calculated to evaluate the fracture toughness showed the similar changing trend with *** adhesion strength reached the maximum of 67 N when the bilayer number is *** surface roughness and friction coefficient decreased with increasing bilayer *** wear mechanism was also investigated,and the results suggested that the multilayer film with bilayer number of 30 exhibited the best wear resistance(1.78×10^(–7)mm^(3)/Nm),benefiting from the contribution of high hardness,fracture toughness and adhesion strength.

关键词： wB_(2)/cr multilayer Magnetron sputtering Bilayer number Tribological behavior

Effect of High Magnetic Field on Growth Behavior of compound Layers during Reactive Diffusion between Solid cu and Liquid Al

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journal of Materials Science & Technology 2011年第9期27卷 856-860页

作者： B. Xu w.P. Tong c.Z. Liu H. zhang L. Zuo j.c. He Key Laboratory of National Education Ministry for Electromagnetic Processing of Materials Northeastern University Shenyang 110004 China Department of Materials Engineering Shenyang Institute of Aeronautical Engineering Shenyang 110034 China

The effect of magnetic field on the growth behavior of compound layer was examined at the interface between the solid cu and liquid AI during reactive diffusion. It was found that the thickness of compound layer was reduced by the high magnetic field. The growth activation energy in β, γ1 and ε2 layers under a high magnetic field was larger than those in non magnetic circumstances, the increment percentage being 4.8%, 13.3% and 5.5%, respectively.

关键词： Diffusion Activation energy High magnetic field Al cu

cu-assisted austenite reversion and enhanced TRIP effect in maraging stainless steels

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journal of Materials Science & Technology 2022年第9期104卷 52-58页

作者： M.c.Niu K.Yang j.H.Luan w.wang Z.B.jiao School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shi-changxu Innovation center for Advance Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Department of Mechanical Engineering The Hong Kong Polytechnic UniversityHong KongChina Department of Materials Science and Engineering City University of Hong KongHong KongChina The Hong Kong Polytechnic University Shenzhen Research Institute ShenzhenGuangdongChina

control of the formation and stability of reverted austenite is critical in achieving a favorable combination of strength,ductility,and toughness in high-strength *** this work,the effects of cu precipitation on the austenite reversion and mechanical properties of maraging stainless steels were investigated by atom probe tomography,transmission electron microscopy,and mechanical *** results indicate that cu accelerates the austenite reversion kinetics in two manners:first,cu,as an austenite stabilizer,increases the equilibrium austenite fraction and hence enhances the chemical driving force for the austenite formation,and second,cu-rich nanoprecipitates promote the austenite reversion by serving as heterogeneous nucleation sites and providing Ni-enriched chemical conditions through interfacial *** addition,the cu precipitation hardening compensates the strength drop induced by the formation of soft reverted *** tensile deformation,the metastable reverted austenite transforms to martensite,which substantially improves the ductility and toughness through a transformation-induced plasticity(TRIP)*** cu-added maraging stainless steel exhibits a superior combination of a yield strength of~1.3 GPa,an elongation of~15%,and an impact toughness of~58 j.

关键词： Maraging stainless steel TRIP effect Austenite reversion cu-rich nanoprecipitate

PREcIPITATION BEHAVIOR OF M_(2)N IN A HIGH-NITROGEN AUSTENITIc STAINLESS STEEL DURING ISOTHERMAL AGING

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Acta Metallurgica Sinica(English Letters) 2007年第2期20卷 95-101页

作者： F. Shi L.j. wang w.F. cui c.M. Liu School of Materials ＆ Metallurgy Northeastern UniversityShenyang 110004 China

The precipitation behavior of M2N and the microstructural evolution in a cr-Mn austenitic stainless steel with a high nitrogen content of 0.43mass% during isothermal aging has been investigated using optical microscopy （ OM）, scanning electron microscopy （SEM）, and transmission electron microscopy （TEM）. The aging treatments have led to the decomposition of nitrogen supersaturated austenitic matrix through discontinuous cellular precipitation. The precipitated cells comprise alternate lamellae of M2N precipitate and austenitic matrix. This kind of precipitate morphology is similar to that of pearlite. However, owing to the non-eutectoidic mechanism of the reaction, the growth characteristic of the cellular precipitates is different from that of pearlite in Fe-c binary alloys. M2N precipitate in the cell possesses a hexagonal crystal structure with the parameters a = 0.4752nm and c = 0.4429nm, and the orientation relationship between the M2V precipitates and austenite determined from the SADP is [01^-10]M2N//[101]γ, [2^-1^-10]M2N//[010]γ.

关键词： austenitic stainless steel high nitrogen microstructureisothermal aging precipitation

EFFEcT OF SUBMERGED ENTRY NOZZLE (SEN) PARAMETERS AND SHAPE ON 3-D FLUID FLOw IN MOULD FOR BEAM BLANK cONTINUOUS cASTING

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Acta Metallurgica Sinica(English Letters) 2004年第5期17卷 705-712页

作者： Y.P.Du j.w.Yang R.Shi X.c.cui SchoolofMaterialScience TaiyuanUniversityofScience＆TechnologyTaiyuan080024China SchoolofMechanism YanshanUniversityQinghuangdao066004China

According to turbulent theory and characteristics of beam blank continuous casting, 3-D model to represent the flow of beam blank mould is established. The predicted results indicate that the exit obliquity of up 15°(+15°) should be adopted, which will benefit the floatation of non-metallic inclusion and purification of the molten steel. when the nozzle angle is 120°, the flow pattern is reasonable. Proper nozzle depth can be 200mm. Turbulent kinetic of meniscus can be reduced by adopting the square nozzle and suitable area of side outlet when casting speed increases. The results are consistent with those of water model experiment, so the model is exact and reasonable. The model can provide important information for design of SEN and defining of immersion depth.

关键词： SEN parameter SEN shape beam blank continuous casting 3-D flow distribution turbulent kinetic energy

Nanocrystal Model for Liquid Metals and Amorphous Metals

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journal of Materials Science & Technology 2010年第1期26卷 69-74页

作者： X.L. Tian, c.w. Zhan, j.X. Hou, X.c. chen and j.j. Sun Key Laboratory of Liquid Structure and Heredity of Materials, Ministry of Education, Shandong University, jinan 250061, china [a] Key Laboratory of Liquid Structure and Heredity of Materials Ministry of Education Shandong University jinan 250061 china

A nanocrystal model for liquid metals and amorphous metals has been developed. with the nanocrystal model, the broadening peak profiles （BPPs） of cu, Al, Al65cu20Fe15 alloy, cu7oNi30 alloy and Fe50Si50 alloy were gained by broadening the X-ray diffraction （XRD） peaks of a crystal lattice. By comparing the BPPs with the XRD intensity curves measured on the liquid metals, it is found that the BPPs are closely in agreement with the XRD intensity curves, respectively, except the FesoSiso alloy. Therefore, the nanocrystal model can be used to determine if the atomic cluster structure of the liquid metal is similar to the structure of its crystal lattice.

关键词： Liquid metal Atomic cluster Structure crystal lattice

Probability to retrieve testicular spermatozoa in azoospermic patients

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Asian journal of Andrology 2000年第3期2卷 199-205页

作者： H.-j.Glanden L.-c.Horn w.Dorschner U.Paasch j.Kratzsch Department of Dermatology/Andrology Unit Department of Dermatology Department of PathologyDepartment of Dermatology Department of UrologyDepartment of Dermatology/Andrology UnitDepartment of Clinical Chemistry and Pathological Biochemistry University of Leipzig D-04103 Leipzig Germany

Aim: The degree of probability to retrieve spermatozoa from testicular tissue for intracytoplasmic sperm injection intooocytes is of interest for counselling of infertility patients. we investigated the relation of sperm retrieval to clinical dataand histological pattern in testicular biopsies from azoospermic patients. Methods: In 264 testicular biopsies from142 azoospermic patients, the testicular tissue was shredded to separate the spermatozoa, histological semi-thin sec-tions of which were then evaluated using johnsen score. Results: The retrieval of spermatozoa correlated signifi-cantly (P with the testicular volume (r = 0.49), the FSH concentration ( r = -0.66), the maximum score(r = 0.85) and the mean johnsen score (r = 0.81). In the multivariate regression analysis the successful testicularsperm extraction showed the closest relationship to the maximum score. The testicular volume correlated significantlywith the mean johnsen score ( r = 0.64, P concentration mainly with the maxi-mum score ( r = -0.77; P with a history cryptorchidism showed a significantly lower johnsenscore compared to the patients who did not have any testicular disease in the past (3.7 ± 2.4 vs. 5.9 ± 2. 5; P conclusion: In a limited range, the testicular volume and the FSH concentration in serum were related to thejohnsen score which correlated significantly with the sperm retrieval. The successful sperm retrieval can be expected inall azoospermic patients irrespective of the results of clinical examination. However, the probability of retrieval of sper-matozoa decreased significantly in patients with a FSH level > 18 U/L, tesficular volume johnsen scorejohnsen score < 7.

关键词： sperm extraction testicular histology azoospermia male infertility follicle stimulating hormone