The non-smooth surface morphology of dung beetle, Copris ochus, was analyzed. The bulldozing plates with bionic geometric non-smooth or the chemical uneven surface were designed for the soil sliding test based on the ...The non-smooth surface morphology of dung beetle, Copris ochus, was analyzed. The bulldozing plates with bionic geometric non-smooth or the chemical uneven surface were designed for the soil sliding test based on the simulation of the bumpy surface of the dung beetle. Special black metals— with different contents of alloys of manganese, silicon, chromium, copper and rare earth— were developed for making geometric non-smooth and chemical uneven surfaces by means of surface welding at the surfaces of a middle carbon steel plate. Four metals, with different surface properties including hardness and water contact angle were used to make the bulldozing plates for measuring the soil sliding resistance. Test results of soil sliding resistance indicate that all the geometric non-smooth plates and the chemical uneven plates reducing soil friction. Considering the materials and surface morphology, the bionic plate can reduce the soil sliding resistance from 18.1 % up to 42.2%, compared to the traditional smooth bulldozing plate made from middle carbon steel. The test results also show that the smaller the normal load, the greater effect on resistance reduction by the bionic non-smooth surface plates.展开更多
Objective: This study was performed with the purpose a report clinical cases involving condylar position and Nóbilo’s sliding plates. Background: Patients may present temporomandibular disorder (TMD), which is c...Objective: This study was performed with the purpose a report clinical cases involving condylar position and Nóbilo’s sliding plates. Background: Patients may present temporomandibular disorder (TMD), which is characterized by pain in masticatory muscles, temporomandibular joints and limited mandible movements. Treatment involving oral rehabilitation with the use of complete dentures with Nóbilo’s sliding plates has been an alternative for the treatment of TMD. Materials and Methods: Nine patients with a history of TMD signs and symptoms (RDC/TMD)—in particular, muscular and articular pain—received pain evaluations, mandibular movement analysis, transcranial radiography and an electromyographic analysis of the masseter and temporalis muscles before and after the use of complete dentures with Nóbilo’s sliding plates. Results: After treatment, the patients had reduced painful symptoms, an increase in mandibular movement and adequate electromyographic activity. The normalized EMG data were ta-bulated and analyzed statistically using SPSS version 17.0 for Windows (SPSS Inc., Chicago, IL, USA), and the values were compared by umpaired independent Student’s t-test. Conclusion: The use of Nóbilo’s sliding plates promoted improvements in electromyographic activity, muscular pain and man-dibular movement.展开更多
The West Henan large sliding structure is located in the southern part of the North China plate. It is a planar structural feature of a relatively large scale. To its northwest lie the Taihang Mountains, and to the so...The West Henan large sliding structure is located in the southern part of the North China plate. It is a planar structural feature of a relatively large scale. To its northwest lie the Taihang Mountains, and to the southwest the Funiu Mountain. In the east it extends between the broad plain and hilly land. Formed in the early Indosinian Period, its main sliding surface is the coal seam II 1 with the sliding direction from NW to SE, and a sliding area of about 23,000 km2. Affected by the big sliding, the coal seam II1 in West Henan occurs in the state of powder, and thickens to the SE. Some small penetrating sliding structures were developed over II 1 in the early Yanshanian Period, causing a disorder on the south border of the North China coal-accumulating basin in the late Palaeozoic Era. An exploration into the West Henan large sliding structure is of great importance in the geological study.展开更多
Magnesium aluminate spinel-corundum composite was prepared with waste slide plate and magnesia carbon brick. Microstructure and sintering ability of as-prepared magnesium aluminate spinel-corundum composite were inves...Magnesium aluminate spinel-corundum composite was prepared with waste slide plate and magnesia carbon brick. Microstructure and sintering ability of as-prepared magnesium aluminate spinel-corundum composite were investigated with XRD, SEM, and DSC/TG. With the addition of waste slide plate increasing or synthesis temperature rising, the bulk density of the specimen increases and the apparent porosity decreases, but the crystallinity of the specimen decreases and the magnesium aluminate spinel phase increases. The obtained composite contains 72% spinel and 26% corundum. Primary phase and secondary phase are bonded by glass phase. The results show that it is feasible to synthesis magnesium aluminate spinel-corundum material with waste slide plate and magnesia carbon brick.展开更多
The zirconia ceramic ring was prepared using fused monoclinic zirconia as main starting material, adopting composite stabilizer of magnesia, yttria and calcium nitrate, and applying recombination technology of traditi...The zirconia ceramic ring was prepared using fused monoclinic zirconia as main starting material, adopting composite stabilizer of magnesia, yttria and calcium nitrate, and applying recombination technology of traditional refractories and ceramics. Effect of the preparation process on material properties was comparatively studied, and the microstructure and phase composition were analyzed. The results show that adopting the high-speed mixing granulation process and the appropriate heat treatment can realize the control on the phase composition and microstructure, the zirconia ceramic ring with good thermal shock resistance and mechanical properties can be prepared.展开更多
Several kinds of slide nozzle plate such as Al2O3-C-ZrO2,MgO,Al2O3,Spinel-C and Al2O3-C SN plate for high oxygen steel used in BaoSteel have been analysed,the appearance and size of the SN plate after using have been ...Several kinds of slide nozzle plate such as Al2O3-C-ZrO2,MgO,Al2O3,Spinel-C and Al2O3-C SN plate for high oxygen steel used in BaoSteel have been analysed,the appearance and size of the SN plate after using have been measured.The Al2O3-C SN plate has longer service life in casting high oxygen steel,and the wear mechanism of different SN plates is discussed.展开更多
The basic formulation of Al2O3- C slide plates was65%( in mass,the same hereinafter) white fused corundum particles,25% white fused corundum fines,6% active α-Al2O3 micropowder,4% carbon black and flake graphite, and...The basic formulation of Al2O3- C slide plates was65%( in mass,the same hereinafter) white fused corundum particles,25% white fused corundum fines,6% active α-Al2O3 micropowder,4% carbon black and flake graphite, and additional 4% phenolic resin.Based on this formulation,3% Al powder,3% Si powder,and 3% Al + 3% Si powder were used to substitute equivalent white corundum fines to improve the hot mechanical properties of Al2O3- C slide plates. The specimens with dimensions of 140 mm × 25 mm × 25 mm were pressed at 150 MPa,dried at 200 ℃ for 24 h,and hot treated at 1 400 ℃ for 3 h in carbon embedded condition. Then hot modulus of rupture and thermal shock resistance of the specimens were tested and the phase compositions and microstructure were analyzed. The results show that specimen with 3% Al powder has the higher hot modulus of rupture but lower residual modulus of rupture after thermal shock than the specimen with3% Si powder; the specimen with 3% Al + 3% Si powders exhibits the highest hot modulus of rupture and the best thermal shock resistance; the change of mechanical property is closely related with the in-situ formed nonoxides: AlN in the form of bars is formed in specimens with Al powder; fibrous SiC whiskers are formed in specimens with Si powder; in the specimens with both Al and Sipowders,besides AlN and SiC whiskers,hexagonal tabular SiAlON is in-situ synthesized,which interlocks with each other.展开更多
The Indo-Pacific convergence region is the best target to solve the teo remaining challenges of the plate tectonics theory,i.e.,subduction initiation and the driving force of plate tectonics.Recent studies proposed th...The Indo-Pacific convergence region is the best target to solve the teo remaining challenges of the plate tectonics theory,i.e.,subduction initiation and the driving force of plate tectonics.Recent studies proposed that the Izu-Bonin subduction initiation belongs to spontaneous initiation,which implies that it started from extension,followed by low angle subduction.Numerical geodynamic modeling suggests that the initiation of plate subduction likely occurred along a transform fault,which put the young spreading ridge in direct contact with old oceanic crust.This,however,does not explain the simultaneous subduction initiation in the west Pacific region in the Cenozoic.Namely,the subduction initiations in the Izu-BoninMariana,the Aleutian,and the Tonga-Kermadec trenches are associated with oceanic crusts of different ages,yet they occurred at roughly the same time,suggesting that they were all triggered by a maj or change in the Pacific plate.Moreover,low angle subduction induces compression rather than extension,which requires external compression forces.Given that the famous Hawaiian-Emperor bending occurred roughly at the same time with the onset of westward subductions in the west Pacific,we propose that these Cenozoic subductions were initiated by the steering of the Pacific plate,which are classified as induced initiation.Induced subduction initiation usually occurs in young ocean basins,forming single-track subduction.The closure s of Neo-Tethys Oceans were likely triggered by plume s in the south,forming northward subductions.Interestingly,the Indian plate kept on moving northward more than 50 Ma after the collision between the Indian and Eurasian continents and the break-off of the subducted oceanic slab attached to it.This strongly suggests that slab pull is not the main driving force of plate tectonics,whereas slab sliding is.展开更多
Previous researches on the mixed mode fracture initiation criteria were mostly focused on opening mode fracture. In this study, the authors proposed a new criterion for mixed mode sliding fracture initiation, which is...Previous researches on the mixed mode fracture initiation criteria were mostly focused on opening mode fracture. In this study, the authors proposed a new criterion for mixed mode sliding fracture initiation, which is the maximum twin shear stress factor criterion. The authors studied a finite width plate with central slant crack, subject to a far field uniform uniaxial tensile or compressive stress.展开更多
文摘The non-smooth surface morphology of dung beetle, Copris ochus, was analyzed. The bulldozing plates with bionic geometric non-smooth or the chemical uneven surface were designed for the soil sliding test based on the simulation of the bumpy surface of the dung beetle. Special black metals— with different contents of alloys of manganese, silicon, chromium, copper and rare earth— were developed for making geometric non-smooth and chemical uneven surfaces by means of surface welding at the surfaces of a middle carbon steel plate. Four metals, with different surface properties including hardness and water contact angle were used to make the bulldozing plates for measuring the soil sliding resistance. Test results of soil sliding resistance indicate that all the geometric non-smooth plates and the chemical uneven plates reducing soil friction. Considering the materials and surface morphology, the bionic plate can reduce the soil sliding resistance from 18.1 % up to 42.2%, compared to the traditional smooth bulldozing plate made from middle carbon steel. The test results also show that the smaller the normal load, the greater effect on resistance reduction by the bionic non-smooth surface plates.
基金This study was supported by the Foundation for Research Support of São Paulo (FAPESP).
文摘Objective: This study was performed with the purpose a report clinical cases involving condylar position and Nóbilo’s sliding plates. Background: Patients may present temporomandibular disorder (TMD), which is characterized by pain in masticatory muscles, temporomandibular joints and limited mandible movements. Treatment involving oral rehabilitation with the use of complete dentures with Nóbilo’s sliding plates has been an alternative for the treatment of TMD. Materials and Methods: Nine patients with a history of TMD signs and symptoms (RDC/TMD)—in particular, muscular and articular pain—received pain evaluations, mandibular movement analysis, transcranial radiography and an electromyographic analysis of the masseter and temporalis muscles before and after the use of complete dentures with Nóbilo’s sliding plates. Results: After treatment, the patients had reduced painful symptoms, an increase in mandibular movement and adequate electromyographic activity. The normalized EMG data were ta-bulated and analyzed statistically using SPSS version 17.0 for Windows (SPSS Inc., Chicago, IL, USA), and the values were compared by umpaired independent Student’s t-test. Conclusion: The use of Nóbilo’s sliding plates promoted improvements in electromyographic activity, muscular pain and man-dibular movement.
文摘The West Henan large sliding structure is located in the southern part of the North China plate. It is a planar structural feature of a relatively large scale. To its northwest lie the Taihang Mountains, and to the southwest the Funiu Mountain. In the east it extends between the broad plain and hilly land. Formed in the early Indosinian Period, its main sliding surface is the coal seam II 1 with the sliding direction from NW to SE, and a sliding area of about 23,000 km2. Affected by the big sliding, the coal seam II1 in West Henan occurs in the state of powder, and thickens to the SE. Some small penetrating sliding structures were developed over II 1 in the early Yanshanian Period, causing a disorder on the south border of the North China coal-accumulating basin in the late Palaeozoic Era. An exploration into the West Henan large sliding structure is of great importance in the geological study.
文摘Magnesium aluminate spinel-corundum composite was prepared with waste slide plate and magnesia carbon brick. Microstructure and sintering ability of as-prepared magnesium aluminate spinel-corundum composite were investigated with XRD, SEM, and DSC/TG. With the addition of waste slide plate increasing or synthesis temperature rising, the bulk density of the specimen increases and the apparent porosity decreases, but the crystallinity of the specimen decreases and the magnesium aluminate spinel phase increases. The obtained composite contains 72% spinel and 26% corundum. Primary phase and secondary phase are bonded by glass phase. The results show that it is feasible to synthesis magnesium aluminate spinel-corundum material with waste slide plate and magnesia carbon brick.
文摘The zirconia ceramic ring was prepared using fused monoclinic zirconia as main starting material, adopting composite stabilizer of magnesia, yttria and calcium nitrate, and applying recombination technology of traditional refractories and ceramics. Effect of the preparation process on material properties was comparatively studied, and the microstructure and phase composition were analyzed. The results show that adopting the high-speed mixing granulation process and the appropriate heat treatment can realize the control on the phase composition and microstructure, the zirconia ceramic ring with good thermal shock resistance and mechanical properties can be prepared.
文摘Several kinds of slide nozzle plate such as Al2O3-C-ZrO2,MgO,Al2O3,Spinel-C and Al2O3-C SN plate for high oxygen steel used in BaoSteel have been analysed,the appearance and size of the SN plate after using have been measured.The Al2O3-C SN plate has longer service life in casting high oxygen steel,and the wear mechanism of different SN plates is discussed.
文摘The basic formulation of Al2O3- C slide plates was65%( in mass,the same hereinafter) white fused corundum particles,25% white fused corundum fines,6% active α-Al2O3 micropowder,4% carbon black and flake graphite, and additional 4% phenolic resin.Based on this formulation,3% Al powder,3% Si powder,and 3% Al + 3% Si powder were used to substitute equivalent white corundum fines to improve the hot mechanical properties of Al2O3- C slide plates. The specimens with dimensions of 140 mm × 25 mm × 25 mm were pressed at 150 MPa,dried at 200 ℃ for 24 h,and hot treated at 1 400 ℃ for 3 h in carbon embedded condition. Then hot modulus of rupture and thermal shock resistance of the specimens were tested and the phase compositions and microstructure were analyzed. The results show that specimen with 3% Al powder has the higher hot modulus of rupture but lower residual modulus of rupture after thermal shock than the specimen with3% Si powder; the specimen with 3% Al + 3% Si powders exhibits the highest hot modulus of rupture and the best thermal shock resistance; the change of mechanical property is closely related with the in-situ formed nonoxides: AlN in the form of bars is formed in specimens with Al powder; fibrous SiC whiskers are formed in specimens with Si powder; in the specimens with both Al and Sipowders,besides AlN and SiC whiskers,hexagonal tabular SiAlON is in-situ synthesized,which interlocks with each other.
基金the Strategic Priority Research Program(B)of the Chinese Academy of Sciences(No.XDB42020203,XDB18020102)the National Key R&D Program of China(No.2016YFC0600408)the Taishan Scholar Program of Shandong(No.TS201712075)。
文摘The Indo-Pacific convergence region is the best target to solve the teo remaining challenges of the plate tectonics theory,i.e.,subduction initiation and the driving force of plate tectonics.Recent studies proposed that the Izu-Bonin subduction initiation belongs to spontaneous initiation,which implies that it started from extension,followed by low angle subduction.Numerical geodynamic modeling suggests that the initiation of plate subduction likely occurred along a transform fault,which put the young spreading ridge in direct contact with old oceanic crust.This,however,does not explain the simultaneous subduction initiation in the west Pacific region in the Cenozoic.Namely,the subduction initiations in the Izu-BoninMariana,the Aleutian,and the Tonga-Kermadec trenches are associated with oceanic crusts of different ages,yet they occurred at roughly the same time,suggesting that they were all triggered by a maj or change in the Pacific plate.Moreover,low angle subduction induces compression rather than extension,which requires external compression forces.Given that the famous Hawaiian-Emperor bending occurred roughly at the same time with the onset of westward subductions in the west Pacific,we propose that these Cenozoic subductions were initiated by the steering of the Pacific plate,which are classified as induced initiation.Induced subduction initiation usually occurs in young ocean basins,forming single-track subduction.The closure s of Neo-Tethys Oceans were likely triggered by plume s in the south,forming northward subductions.Interestingly,the Indian plate kept on moving northward more than 50 Ma after the collision between the Indian and Eurasian continents and the break-off of the subducted oceanic slab attached to it.This strongly suggests that slab pull is not the main driving force of plate tectonics,whereas slab sliding is.
文摘Previous researches on the mixed mode fracture initiation criteria were mostly focused on opening mode fracture. In this study, the authors proposed a new criterion for mixed mode sliding fracture initiation, which is the maximum twin shear stress factor criterion. The authors studied a finite width plate with central slant crack, subject to a far field uniform uniaxial tensile or compressive stress.
