The paper approaches the problem of the command functions of galvanometer-based scanners (GS) that are necessary to produce the linear plus parabolic scanning function of the GS, which we have proved previously to p...The paper approaches the problem of the command functions of galvanometer-based scanners (GS) that are necessary to produce the linear plus parabolic scanning function of the GS, which we have proved previously to produce the highest possible duty cycle (i.e., time efficiency) of the device. We have completed this theoretical aspect (which contradicted what has been stated previously in the literature, where it has been considered that the linear plus sinusoidal scanning function was the best) with the experimental study of the most used scanning functions of the GSs (sawtooth, sinusoidal and triangular), with applications in biomedical imaging, in particular in optical coherence tomography, demonstrating that the triangular function is always the best one to be applied, from both an optical and a mechanical point of view. In the present study the input voltage/command function which should be applied to the GS to produce the desired triangular scanning function (with controlled non-linearity for the fastest possible stop-and-turn portions) was determined analytically, in relationship with the active torque that drives the device. This command function is analyzed with regard to the specific, respectively required parameters of the GS: natural frequency and damping factor, respectively scan speed and amplitude. The modeling in an open loop control structure of the GS is finally discussed as a trade-off between using the highest possible duty cycle and minimizing the maximum peaks of the input voltage.展开更多
Current research and ways of capturing mechanical energy are discussed in this paper. By the aid of the comprehensive thermodynamic analysis and Aspen simulation tool, the amount of a vailable work that can be produc...Current research and ways of capturing mechanical energy are discussed in this paper. By the aid of the comprehensive thermodynamic analysis and Aspen simulation tool, the amount of a vailable work that can be produced from capturing the pressure energy has been calculated. Based on the comprehensive thermodynamic analysis, two systems have been proposed to capture pressure energy of natural gas to generate electricity. In this study, the expression of exergy is given which can be used in evaluating purposes. A problem with this multidisciplinary study is the complicated boundary condition. In conclusion, a technical prospect on recoverable natural gas pressure energy has been presented based on total energy system theory.展开更多
为了系统分析产品社会生命周期评价的研究进展和技术框架,采用CiteSpace对来源于中国知网、Web of Science数据库的文献进行计量分析。结果表明:产品社会生命周期评价研究热点演进分为框架搭建(2008—2013年)、方法探索(2013—2016年)...为了系统分析产品社会生命周期评价的研究进展和技术框架,采用CiteSpace对来源于中国知网、Web of Science数据库的文献进行计量分析。结果表明:产品社会生命周期评价研究热点演进分为框架搭建(2008—2013年)、方法探索(2013—2016年)和体系标准化(2017—2020年)3个阶段;产品社会生命周期评价技术框架包括确定目标与范围、清单分析、影响评价与结果解释4个部分,清单分析的指标选择过程涉及40个子指标,其中与健康、人权相关的为核心指标;社会影响特征化可以通过参考量表法与影响路径法进行量化,参考量表法包括子类别评价法与社会热点数据库法,其中子类别评价法体系较为完善。展开更多
3-Aminopropyltriethoxysilane functionalized worm-like mesoporous silica monolithic(WMSM-NH2) was prepared and used as a new regenerable adsorbent for the removal of Cu2+ ions. The analysis results show that the WMS...3-Aminopropyltriethoxysilane functionalized worm-like mesoporous silica monolithic(WMSM-NH2) was prepared and used as a new regenerable adsorbent for the removal of Cu2+ ions. The analysis results show that the WMSM-NH2 monolithic had a high efficiency value of 99.3% for Cu2+ remediation when the Cu2+ solution was at an initial concentration of 10.32 mg/L. The regeneration study of the WMSM-NH2 monolithic presented that the adsorp- tion efficiency of 89.0% was remained and a mass of 92.0% was left after seven adsorption-desorption cycles were executed. The monolithic material with high resistance to the acid and good mechanical stability can facilitate the operations of adsorption and regeneration of the adsorbent.展开更多
基金the support of the US Department of State through Fulbright Scholar Grant 474/2009
文摘The paper approaches the problem of the command functions of galvanometer-based scanners (GS) that are necessary to produce the linear plus parabolic scanning function of the GS, which we have proved previously to produce the highest possible duty cycle (i.e., time efficiency) of the device. We have completed this theoretical aspect (which contradicted what has been stated previously in the literature, where it has been considered that the linear plus sinusoidal scanning function was the best) with the experimental study of the most used scanning functions of the GSs (sawtooth, sinusoidal and triangular), with applications in biomedical imaging, in particular in optical coherence tomography, demonstrating that the triangular function is always the best one to be applied, from both an optical and a mechanical point of view. In the present study the input voltage/command function which should be applied to the GS to produce the desired triangular scanning function (with controlled non-linearity for the fastest possible stop-and-turn portions) was determined analytically, in relationship with the active torque that drives the device. This command function is analyzed with regard to the specific, respectively required parameters of the GS: natural frequency and damping factor, respectively scan speed and amplitude. The modeling in an open loop control structure of the GS is finally discussed as a trade-off between using the highest possible duty cycle and minimizing the maximum peaks of the input voltage.
基金Supported by Tianjin Institute of Urban Construction(03046)
文摘Current research and ways of capturing mechanical energy are discussed in this paper. By the aid of the comprehensive thermodynamic analysis and Aspen simulation tool, the amount of a vailable work that can be produced from capturing the pressure energy has been calculated. Based on the comprehensive thermodynamic analysis, two systems have been proposed to capture pressure energy of natural gas to generate electricity. In this study, the expression of exergy is given which can be used in evaluating purposes. A problem with this multidisciplinary study is the complicated boundary condition. In conclusion, a technical prospect on recoverable natural gas pressure energy has been presented based on total energy system theory.
文摘为了系统分析产品社会生命周期评价的研究进展和技术框架,采用CiteSpace对来源于中国知网、Web of Science数据库的文献进行计量分析。结果表明:产品社会生命周期评价研究热点演进分为框架搭建(2008—2013年)、方法探索(2013—2016年)和体系标准化(2017—2020年)3个阶段;产品社会生命周期评价技术框架包括确定目标与范围、清单分析、影响评价与结果解释4个部分,清单分析的指标选择过程涉及40个子指标,其中与健康、人权相关的为核心指标;社会影响特征化可以通过参考量表法与影响路径法进行量化,参考量表法包括子类别评价法与社会热点数据库法,其中子类别评价法体系较为完善。
基金Supported by the National Natural Science Foundation of China(Nos. 50573030 and 21171065).
文摘3-Aminopropyltriethoxysilane functionalized worm-like mesoporous silica monolithic(WMSM-NH2) was prepared and used as a new regenerable adsorbent for the removal of Cu2+ ions. The analysis results show that the WMSM-NH2 monolithic had a high efficiency value of 99.3% for Cu2+ remediation when the Cu2+ solution was at an initial concentration of 10.32 mg/L. The regeneration study of the WMSM-NH2 monolithic presented that the adsorp- tion efficiency of 89.0% was remained and a mass of 92.0% was left after seven adsorption-desorption cycles were executed. The monolithic material with high resistance to the acid and good mechanical stability can facilitate the operations of adsorption and regeneration of the adsorbent.