The paper firstly analyzes the influence factor on material removal rate of curved optical work-pieces in the bonnet polishing. Then the experiments are conducted to reveal the effects of several polishing parameters ...The paper firstly analyzes the influence factor on material removal rate of curved optical work-pieces in the bonnet polishing. Then the experiments are conducted to reveal the effects of several polishing parameters on the material removal rate when the spherical optical glasses are polished with different curvature radius, such as the decrement of the bonnet, the rotational speed of the bonnet and the curvature radius of the work-piece＇s surface using a bonnet trial-manufacturing machine developed by our assignment groups. In the end, the curvilinear relationships between these parameters and the material removal rate are acquired and the laws of the effects on material removal rate in bonnet polishing by several parameters are given. When the spherical-pieces are polished with smaller curvature radius, it is not proportional to either bonnet decrement or bonnet rotational speed as described by the Preston equation although the removal rate increases as the relative velocity or the applied pressure increases. Therefore, for the purpose of calculating more accurately the material removal of the spherical work-pieces, the Preston equation should be modified and studied further.展开更多
The effect of particle shape on the porosity and compressive strength of porous hydroxyapatite （HA） scaffolds was investigated by sintering the mixture of rod-shaped HA （r-HA） and spherical HA （s-HA） with polyac...The effect of particle shape on the porosity and compressive strength of porous hydroxyapatite （HA） scaffolds was investigated by sintering the mixture of rod-shaped HA （r-HA） and spherical HA （s-HA） with polyacrylamide used as the sacrificial template. It was found, for the first time, that addition of r-HA into s-HA could exponentially decrease the porosity of sintered HA scaffolds and enhance their compressive strength with the increase of r-HA content. The mechanism, according to the results from scanning electron microscopy and X-ray diffraction, lies in the restriction of s-HA to the grain formation and growth of r-HA during sintering and results in the fusion of r-HA with s-HA. These findings suggest that mixture of r-HA and s-HA might provide a new and facile way to improve the compressive strength of oorous HA scaffolds.展开更多
Oil and gas will remain the dominant components of global primary energy consumption during the energy transition period.Innovations in petroleum geology and exploration and development technologies are critical for a...Oil and gas will remain the dominant components of global primary energy consumption during the energy transition period.Innovations in petroleum geology and exploration and development technologies are critical for advancing the energy revolution.Building on a systematic review of the formation and evolution of classical petroleum geology,this paper proposes a new theoretical content and research framework of multi-spheric interaction-driven hydrocarbon formation and enrichment through in-depth analyses of the Earth's multi-spheric coupling mechanisms and cross-spheric cycling processes of volatiles.The core concept of this new theory lies in the principles of Earth system science and multi-spheric interactions,and the aim is to unravel the interplay between Earth system materials and energy cycles and dynamic processes in controlling hydrocarbon formation and enrichment.We reassess the global oil and gas resource potential and identify future exploration priorities and frontier domains for petroleum geology.By focusing on volatile-mediated multi-spheric exchange processes and setting them as a breakthrough,this framework aims to examine the genetic linkages among deep Earth processes,climatic environments,basin evolution,biological activities,and petroleum systems.The additional goals of this research are to decode the spatiotemporal distribution of hydrocarbon resources across diverse scales and types and to establish a novel theoretical paradigm for optimizing target prioritization of both mature field revitalization and frontier play assessment.By integrating the theory of multi-spheric interaction-driven hydrocarbon formation and enrichment with the artificial intelligence powered large-scale model tailored to the petroleum exploration and production industry,this initiative provides transformative scientific and technological underpinning for advancing the ongoing global energy revolution.展开更多
基金Foundation of Harbin Institute of Technology,China(No.HIT.2001.10)Harbin Municipal Youth Foundation of China(No.2002AFQXJ040).
文摘The paper firstly analyzes the influence factor on material removal rate of curved optical work-pieces in the bonnet polishing. Then the experiments are conducted to reveal the effects of several polishing parameters on the material removal rate when the spherical optical glasses are polished with different curvature radius, such as the decrement of the bonnet, the rotational speed of the bonnet and the curvature radius of the work-piece＇s surface using a bonnet trial-manufacturing machine developed by our assignment groups. In the end, the curvilinear relationships between these parameters and the material removal rate are acquired and the laws of the effects on material removal rate in bonnet polishing by several parameters are given. When the spherical-pieces are polished with smaller curvature radius, it is not proportional to either bonnet decrement or bonnet rotational speed as described by the Preston equation although the removal rate increases as the relative velocity or the applied pressure increases. Therefore, for the purpose of calculating more accurately the material removal of the spherical work-pieces, the Preston equation should be modified and studied further.
基金supported by the National Natural Science Foundation of China (Nos. 11532004 and 31370946)the National Science and Technology Support Program of China (No. 2012BAI17B03-4)+1 种基金the Development of Strategic Emerging Industries of Shenzhen Project (Nos. JCYJ20140417113430596 and CXZZ201404171134 30716)the Science and Technology Project of Guangdong Province (No. 2015A010105021)
文摘The effect of particle shape on the porosity and compressive strength of porous hydroxyapatite （HA） scaffolds was investigated by sintering the mixture of rod-shaped HA （r-HA） and spherical HA （s-HA） with polyacrylamide used as the sacrificial template. It was found, for the first time, that addition of r-HA into s-HA could exponentially decrease the porosity of sintered HA scaffolds and enhance their compressive strength with the increase of r-HA content. The mechanism, according to the results from scanning electron microscopy and X-ray diffraction, lies in the restriction of s-HA to the grain formation and growth of r-HA during sintering and results in the fusion of r-HA with s-HA. These findings suggest that mixture of r-HA and s-HA might provide a new and facile way to improve the compressive strength of oorous HA scaffolds.
基金supported by the National Natural Science Foundation of China(Grant Nos.42288201,42202162,92255303,and 42372162)。
文摘Oil and gas will remain the dominant components of global primary energy consumption during the energy transition period.Innovations in petroleum geology and exploration and development technologies are critical for advancing the energy revolution.Building on a systematic review of the formation and evolution of classical petroleum geology,this paper proposes a new theoretical content and research framework of multi-spheric interaction-driven hydrocarbon formation and enrichment through in-depth analyses of the Earth's multi-spheric coupling mechanisms and cross-spheric cycling processes of volatiles.The core concept of this new theory lies in the principles of Earth system science and multi-spheric interactions,and the aim is to unravel the interplay between Earth system materials and energy cycles and dynamic processes in controlling hydrocarbon formation and enrichment.We reassess the global oil and gas resource potential and identify future exploration priorities and frontier domains for petroleum geology.By focusing on volatile-mediated multi-spheric exchange processes and setting them as a breakthrough,this framework aims to examine the genetic linkages among deep Earth processes,climatic environments,basin evolution,biological activities,and petroleum systems.The additional goals of this research are to decode the spatiotemporal distribution of hydrocarbon resources across diverse scales and types and to establish a novel theoretical paradigm for optimizing target prioritization of both mature field revitalization and frontier play assessment.By integrating the theory of multi-spheric interaction-driven hydrocarbon formation and enrichment with the artificial intelligence powered large-scale model tailored to the petroleum exploration and production industry,this initiative provides transformative scientific and technological underpinning for advancing the ongoing global energy revolution.
