This paper explores how dissolution and precipitation reactions are coupled in batch reactor experimental systems at elevated temperatures. This is the fifth paper in our series of ‘‘Coupled Alkali Feldspar Dissolut...This paper explores how dissolution and precipitation reactions are coupled in batch reactor experimental systems at elevated temperatures. This is the fifth paper in our series of ‘‘Coupled Alkali Feldspar Dissolution and Secondary Mineral Precipitation in Batch Systems.'' In the previous four papers we presented batch experiments of alkali-feldspar hydrolysis and explored the coupling of dissolution and precipitation reactions(Fu et al. in Chem Geol91:955–964, 2009; Zhu and Lu in Geochim Cosmochim Acta 73:3171–3200, 2009; Zhu et al.in Geochim Cosmochim Acta 74:3963–3983, 2010; Lu et al. in Appl Geochem30:75–90, 2013). Here, we present the results of additionalK-rich feldspar hydrolysis experiments at 150 °C. Our solution chemistry measurements have constrained feldspar dissolution rates, and our high resolution transmission electron microscopy work has identified boehmite precipitation. Reaction path modeling of K-feldspar dissolution and boehmite precipitation simulated the coupled reactions, but only with forced changes of boehmite rate law in the middle of experimental duration. The results which are reported in this article lend further support to our hypothesis that slow secondary mineral precipitation explains part of the wellknown apparent discrepancy between lab measured and field estimated feldspar dissolution rates(Zhu et al. in Water–rock interaction, 2004).展开更多
Operating systems research has traditionally consisted of adding functions to the operating system or inventing and study new implementations. Regardless of the research goal, the single constant has been that the siz...Operating systems research has traditionally consisted of adding functions to the operating system or inventing and study new implementations. Regardless of the research goal, the single constant has been that the size and complexity of operating system increase over time. As a result, operating systems become the most single complex piece of software in a computer system. Today's operating system research is aimed at finding new ways to construct the operating system in order to increase its flexibility, allowing it to adapt to change in designing such extensible systems and the array of choices facing the operating system designer. We discuss such question for describing extensible operating systems and then advance four key design point for extensible operating systems, we analyze and argue each point that relate to different extensible technology. Provide scientific methodology for Operaring systems research or development.展开更多
对于海量实时数据而言,基于Flink on YARN平台可以对这些数据进行并行化处理。在接下来的工作机制和相关技术中,重点分析了基于此平台典型的流架构的数据传输模式,在此基础上,比对了流处理系统和批处理系统的差异点。对于不同数据处理系...对于海量实时数据而言,基于Flink on YARN平台可以对这些数据进行并行化处理。在接下来的工作机制和相关技术中,重点分析了基于此平台典型的流架构的数据传输模式,在此基础上,比对了流处理系统和批处理系统的差异点。对于不同数据处理系统,分析总结了Flink所面临的一些挑战,希望以此为Flink的进一步研究提供参考。展开更多
Biochar is charcoal produced at comparatively high temperature and used as an agricultural amendment, which also sequesters carbon. Most of the research on biochar manufacture in the United States has either focused o...Biochar is charcoal produced at comparatively high temperature and used as an agricultural amendment, which also sequesters carbon. Most of the research on biochar manufacture in the United States has either focused on large-scale continuous systems with multiple products or small batch systems with biochar as the only product. At James Madison University in Harrisonburg, Virginia, we have worked on a batch system to make high quality biochar while capturing the heat for use either as a backup system for hot water heating, or to heat a greenhouse in winter. The system is now in its third iteration. In the first, we used a small intramural grant to experiment with low cost material using a minimalist design. While the unit captured some heat, operation of the design was smoky and hazardous to handle. The second design, funded by a larger intramural research grant, captured considerable heat, made 8-10 kg of biochar per burn and captured up to 250 MJ per batch of biochar made, but remained smoky. The third generation pyrolysis unit was constructed on Avalon Acres Farm in Broadway, Virginia, funded by a 25 × 25 grant through James Madison University （JMU）. This unit makes the same amount of biochar, with less smoke, and sends the captured heat to a storage tank to help heat a greenhouse and home on the site. Our average efficiency of heat transfer is 12.5% of the total heat value of the starting woody biomass, a number we believe can at least double.展开更多
The equilibrium uptake of phenol and lead（II） ions, both singly and in combination, by granular activated carbon was studied in a batch system. The initial pH, temperature, mixing speed and contact time were fixed a...The equilibrium uptake of phenol and lead（II） ions, both singly and in combination, by granular activated carbon was studied in a batch system. The initial pH, temperature, mixing speed and contact time were fixed at 4, 30 ℃, 250 rpm and 6 hrs respectively. Adsorption isotherms were developed for both the single and binary component systems and expressed by ten models for single and four models for binary systems and model parameters were estimated by the non-linear regression method using STATISTICA version-6 and EXCEEL-2007 software. The maximum loading capacity （qm） of the phenol was 66.8234, 60.4823 mg/g and 37.0370, 13.0988 mg/g for lead in single and binary systems respectively. Desorption experiments indicate that the desorption efficiency with 0.1 M NaOH, 0.1 M HCI solution reaches 97.35%, 98% for phenol and lead respectively. There was only 3.58%, 4.93% decrease in removal efficiency for phenol and lead respectively when used regenerated GAC for one cycle.展开更多
基金grant from the State Key Laboratory of Ore Deposits at the Institute of Geochemistry, Chinese Academy of Sciences
文摘This paper explores how dissolution and precipitation reactions are coupled in batch reactor experimental systems at elevated temperatures. This is the fifth paper in our series of ‘‘Coupled Alkali Feldspar Dissolution and Secondary Mineral Precipitation in Batch Systems.'' In the previous four papers we presented batch experiments of alkali-feldspar hydrolysis and explored the coupling of dissolution and precipitation reactions(Fu et al. in Chem Geol91:955–964, 2009; Zhu and Lu in Geochim Cosmochim Acta 73:3171–3200, 2009; Zhu et al.in Geochim Cosmochim Acta 74:3963–3983, 2010; Lu et al. in Appl Geochem30:75–90, 2013). Here, we present the results of additionalK-rich feldspar hydrolysis experiments at 150 °C. Our solution chemistry measurements have constrained feldspar dissolution rates, and our high resolution transmission electron microscopy work has identified boehmite precipitation. Reaction path modeling of K-feldspar dissolution and boehmite precipitation simulated the coupled reactions, but only with forced changes of boehmite rate law in the middle of experimental duration. The results which are reported in this article lend further support to our hypothesis that slow secondary mineral precipitation explains part of the wellknown apparent discrepancy between lab measured and field estimated feldspar dissolution rates(Zhu et al. in Water–rock interaction, 2004).
文摘Operating systems research has traditionally consisted of adding functions to the operating system or inventing and study new implementations. Regardless of the research goal, the single constant has been that the size and complexity of operating system increase over time. As a result, operating systems become the most single complex piece of software in a computer system. Today's operating system research is aimed at finding new ways to construct the operating system in order to increase its flexibility, allowing it to adapt to change in designing such extensible systems and the array of choices facing the operating system designer. We discuss such question for describing extensible operating systems and then advance four key design point for extensible operating systems, we analyze and argue each point that relate to different extensible technology. Provide scientific methodology for Operaring systems research or development.
文摘对于海量实时数据而言,基于Flink on YARN平台可以对这些数据进行并行化处理。在接下来的工作机制和相关技术中,重点分析了基于此平台典型的流架构的数据传输模式,在此基础上,比对了流处理系统和批处理系统的差异点。对于不同数据处理系统,分析总结了Flink所面临的一些挑战,希望以此为Flink的进一步研究提供参考。
文摘Biochar is charcoal produced at comparatively high temperature and used as an agricultural amendment, which also sequesters carbon. Most of the research on biochar manufacture in the United States has either focused on large-scale continuous systems with multiple products or small batch systems with biochar as the only product. At James Madison University in Harrisonburg, Virginia, we have worked on a batch system to make high quality biochar while capturing the heat for use either as a backup system for hot water heating, or to heat a greenhouse in winter. The system is now in its third iteration. In the first, we used a small intramural grant to experiment with low cost material using a minimalist design. While the unit captured some heat, operation of the design was smoky and hazardous to handle. The second design, funded by a larger intramural research grant, captured considerable heat, made 8-10 kg of biochar per burn and captured up to 250 MJ per batch of biochar made, but remained smoky. The third generation pyrolysis unit was constructed on Avalon Acres Farm in Broadway, Virginia, funded by a 25 × 25 grant through James Madison University （JMU）. This unit makes the same amount of biochar, with less smoke, and sends the captured heat to a storage tank to help heat a greenhouse and home on the site. Our average efficiency of heat transfer is 12.5% of the total heat value of the starting woody biomass, a number we believe can at least double.
文摘The equilibrium uptake of phenol and lead（II） ions, both singly and in combination, by granular activated carbon was studied in a batch system. The initial pH, temperature, mixing speed and contact time were fixed at 4, 30 ℃, 250 rpm and 6 hrs respectively. Adsorption isotherms were developed for both the single and binary component systems and expressed by ten models for single and four models for binary systems and model parameters were estimated by the non-linear regression method using STATISTICA version-6 and EXCEEL-2007 software. The maximum loading capacity （qm） of the phenol was 66.8234, 60.4823 mg/g and 37.0370, 13.0988 mg/g for lead in single and binary systems respectively. Desorption experiments indicate that the desorption efficiency with 0.1 M NaOH, 0.1 M HCI solution reaches 97.35%, 98% for phenol and lead respectively. There was only 3.58%, 4.93% decrease in removal efficiency for phenol and lead respectively when used regenerated GAC for one cycle.
