A Ni layer with a thickness of about 100 nm was sputtered on Cu substrates,followed by an ultrasonic seeding with nanodiamond suspension.High-quality diamond film with its crystalline grains close to thermal equilibri...A Ni layer with a thickness of about 100 nm was sputtered on Cu substrates,followed by an ultrasonic seeding with nanodiamond suspension.High-quality diamond film with its crystalline grains close to thermal equilibrium shape was deposited on Cu substrates by hot-filament chemical vapor deposition（HF-CVD）,and the sp2 carbon content was less than 5.56%.The nucleation and growth of diamond film were investigated by micro-Raman spectroscopy,scanning electron microscopy,and X-ray diffraction.The results show that the nucleation density of diamond on the Ni-modified Cu substrates is 10 times higher than that on blank Cu substrates.The enhancement mechanism of the nucleation kinetics by Ni modification layer results from two effects：namely,the nanometer rough Ni-modified surface shows an improved absorption of nanodiamond particles that act as starting points for the diamond nucleation during HF-CVD process;the strong catalytic effect of the Ni-modified surface causes the formation of graphite layer that acts as an intermediate to facilitate diamond nucleation quickly.展开更多
The differential cubature solution to the problem of a Mindlin plate lying on the Winkler foundation with two simply supported edges and two clamped edges was derived.Discrete numerical technology and shape functions ...The differential cubature solution to the problem of a Mindlin plate lying on the Winkler foundation with two simply supported edges and two clamped edges was derived.Discrete numerical technology and shape functions were used to ensure that the solution is suitable to irregular shaped plates.Then,the mechanical model and the solution were employed to model the protection layer that isolates the mining stopes from sea water in Sanshandao gold mine,which is the first subsea mine of China.Furthermore,thickness optimizations for the protection layers above each stope were conducted based on the maximum principle stress criterion,and the linear relations between the best protection layer thickness and the stope area under different safety factors were regressed to guide the isolation design.The method presented in this work provides a practical way to quickly design the isolation layer thickness in subsea mining.展开更多
The Ni-Cr alloy electrodepositing technology on iron substrate in the chlorid-sulfate solution and the impacts of main processing parameters on coating composition were studied. The optimal Ni-Cr alloy electrodepositi...The Ni-Cr alloy electrodepositing technology on iron substrate in the chlorid-sulfate solution and the impacts of main processing parameters on coating composition were studied. The optimal Ni-Cr alloy electrodepositing conditions are that the cathode current density is 16 A/dm^2,the plating solution temperature is 30℃ and the pH value is 2.5. The bright, compact coating gained under the optimal conditions has good cohesion and 24.1% Cr content. The results show that the coating is composed of crystalline, the average grain size is 82 nm and the higher the Cr content of coating, the larger the rigidity, and the higher the corrosion resistance. The rigidity of coating reaches 78.6(HR30T) and the passivation area broadens to 1.4 V when the Cr content of coating is 24.1%.展开更多
基金Project(20110933K) supported by the State Key Laboratory of Powder Metallurgy,ChinaProject(2012QNZT002) supported by the Freedom Explore Program of Central South University,ChinaProject(CSUZC2012024) supported by the Open-End Fund for the Valuable and Precision Instruments of Central South University,China
文摘A Ni layer with a thickness of about 100 nm was sputtered on Cu substrates,followed by an ultrasonic seeding with nanodiamond suspension.High-quality diamond film with its crystalline grains close to thermal equilibrium shape was deposited on Cu substrates by hot-filament chemical vapor deposition（HF-CVD）,and the sp2 carbon content was less than 5.56%.The nucleation and growth of diamond film were investigated by micro-Raman spectroscopy,scanning electron microscopy,and X-ray diffraction.The results show that the nucleation density of diamond on the Ni-modified Cu substrates is 10 times higher than that on blank Cu substrates.The enhancement mechanism of the nucleation kinetics by Ni modification layer results from two effects：namely,the nanometer rough Ni-modified surface shows an improved absorption of nanodiamond particles that act as starting points for the diamond nucleation during HF-CVD process;the strong catalytic effect of the Ni-modified surface causes the formation of graphite layer that acts as an intermediate to facilitate diamond nucleation quickly.
基金Projects(51504044,51204100)supported by National Natural Science Foundation of ChinaProject(14KF05)supported by the Research Fund of The State Key Laboratory of Coal Resources and Mine Safety,CUMT,China+3 种基金Project(cstc2016jcyj A1861)supported by the Research Fund of Chongqing Basic Science and Cutting-Edge Technology Special Projects,ChinaProject(2015CDJXY)supported by the Fundamental Research Funds for the Central UniversitiesProject supported by the China Postdoctoral Science FoundationProject(2011DA105287-MS201503)supported by the Independent Subject of State Key Laboratory of Coal Mine Disaster Dynamics and Control,China
文摘The differential cubature solution to the problem of a Mindlin plate lying on the Winkler foundation with two simply supported edges and two clamped edges was derived.Discrete numerical technology and shape functions were used to ensure that the solution is suitable to irregular shaped plates.Then,the mechanical model and the solution were employed to model the protection layer that isolates the mining stopes from sea water in Sanshandao gold mine,which is the first subsea mine of China.Furthermore,thickness optimizations for the protection layers above each stope were conducted based on the maximum principle stress criterion,and the linear relations between the best protection layer thickness and the stope area under different safety factors were regressed to guide the isolation design.The method presented in this work provides a practical way to quickly design the isolation layer thickness in subsea mining.
基金Project (59674025) supported by the National Natural Science Foundation of China
文摘The Ni-Cr alloy electrodepositing technology on iron substrate in the chlorid-sulfate solution and the impacts of main processing parameters on coating composition were studied. The optimal Ni-Cr alloy electrodepositing conditions are that the cathode current density is 16 A/dm^2,the plating solution temperature is 30℃ and the pH value is 2.5. The bright, compact coating gained under the optimal conditions has good cohesion and 24.1% Cr content. The results show that the coating is composed of crystalline, the average grain size is 82 nm and the higher the Cr content of coating, the larger the rigidity, and the higher the corrosion resistance. The rigidity of coating reaches 78.6(HR30T) and the passivation area broadens to 1.4 V when the Cr content of coating is 24.1%.
