The microemulsified acid system composed by diesel oil, hydrochloric acid and emulsifier was investi- gated in this paper. The stability of microemulsified acid and the phase behavior of the microemulsified system Wer...The microemulsified acid system composed by diesel oil, hydrochloric acid and emulsifier was investi- gated in this paper. The stability of microemulsified acid and the phase behavior of the microemulsified system Were studied. The size distribution and the corrosion inhibition performance were also observed. The results showed that the diesel oil microemulsified acid system possessed small size and good stability under different temperature.The tolerance to CaCl2 reached 80 g·L^-1. Compared with the same concentration hydrochloric acid solution, the corrosion inhibition performance of the diesel oil microemulsified acid system was remarkable.展开更多
The synthesis route was investigated and optimized for the preparation of iminodiacetic acid-polyethylene glycol (IDA-PEG) for immobilized metal ion affinity partitioning in aqueous two-phase systems. IDA-PEG was synt...The synthesis route was investigated and optimized for the preparation of iminodiacetic acid-polyethylene glycol (IDA-PEG) for immobilized metal ion affinity partitioning in aqueous two-phase systems. IDA-PEG was synthesized from PEG in two steps by the reaction of iminodiacetic acid with a monosubstituted derivative of epichlorohydrin-activated PEG. The Cu2+ content combined with IDA-PEG was determined by atomic absorption spectrometry as 0.5 mol·mol^-1 (PEG). Furthermore, the affinity partitioning behavior of lactate dehydrogenase in polyethylene glycol/hydroxypropyl starch aqueous two-phase systems was studied to clarify the affinity effect of the Cu(Ⅱ)-IDA-PEG.展开更多
There has been increasing research in developing offline web applications. This paper concentrates on developing a new methodology for the online assessment web applications that could be used while offline. It is imp...There has been increasing research in developing offline web applications. This paper concentrates on developing a new methodology for the online assessment web applications that could be used while offline. It is important to retrieve the critical data collected during an examination without a provision of a backup mechanism. There is a need for an assessment system that can adapt to work uninterruptedly and without loss of critical data while there is intermittent intemet discontinuity. This paper describes architecture and implementation of online assessment system with offline capabilities. Online assessment system with offline capabilities will not interrupt examinee's experience while appearing for an assessment test if intemet connection is not available. A development methodology is designed and a compliant framework is implemented to enhance online assessment system with offline capabilities.展开更多
A new reaction system was designed to economically convert glucose to lactic acid environment-friendly. Hydrophobic ionic liquids were chosen as solvent that can promote the decomposition reaction of glucose, and the ...A new reaction system was designed to economically convert glucose to lactic acid environment-friendly. Hydrophobic ionic liquids were chosen as solvent that can promote the decomposition reaction of glucose, and the catalytic performance of the solid bases was evaluated. Both the reaction temperature and time can affect the yield of lactic acid. A high yield (97%) of lactic acid was achieved under the optimal reaction condition. The IH NMR spectra and HPLC-MS were used to identify the formation of the lactic acid and variations of ionic liquid. It is found that ionic-liquids have a unique solvent effect for glucose and bases. Water can be used as solvent to extract calcium lactate. This shows a great potential of hydrophobic ionic liquids in the solid bases catalyzed reaction that is limited by the weak solubility of solid bases in organic and water solution.展开更多
In the established apparatus, the conversion ratios of cellulose sulfation (X) under different sulfation conditions were measured. The range of temperature was from -5℃ to +5℃, and the H2SO4 concentration was from 3...In the established apparatus, the conversion ratios of cellulose sulfation (X) under different sulfation conditions were measured. The range of temperature was from -5℃ to +5℃, and the H2SO4 concentration was from 3.1 mol·L-1 to 4.5mol·L-1. The experimental results were used for the establishment of the kinetic model for cellulose sulfation. With the model, X values and the yield of NaCS (Y) can be calculated, thus the reaction with respect to H2SO4 concentration is determined to be third order.展开更多
Noble and active gases are released from geological samples during gas extraction for noble gas isotope analyses. The active gases should be removed before inletting to mass spectrometers for the analyses. The normal ...Noble and active gases are released from geological samples during gas extraction for noble gas isotope analyses. The active gases should be removed before inletting to mass spectrometers for the analyses. The normal noble gas preparation systems can clean up most geological samples. However, authigenic minerals from sedimentary rocks in oil/gas fields contain organic matter, which cannot be cleaned up by the normal preparation systems and thus influence the noble gas analyses. We introduce a novel gas purification system (PRC patent No. ZL201320117751.2), which includes several reversible purification pumps with different absorbing and degassing temperatures. It can well clean up water steam, carbon dioxide and organic gas- es. Mica minerals are often used for 40Ar/39Ar dating. A muscovite sample (2082MS) which could not be cleaned up by the normal preparation system with two SAES NP10 getters, becomes the test sample for a comparative experiment in this study. The experiment is assigned into 4 sections with the organic gas removal system (OGRS) "Closed/Opened" in turn. When the OGRS is closed only with two NP10 getters for purification, the 40At intensities increase in curves with inlet time because of impurities, the 40Ar/39Ar dating results yield age errors about +2%-±1% (20-). When the OGRS is opened for purification, in contrast, the 40Ar intensities decrease linearly with inlet time. This indicates that the gases have been cleaned up effectively, and the 40Ar/39Ar results yield ages with errors in ±0.4%. The OGRS is very helpful to obtain high-quality analysis data.展开更多
Long-range magnetic orders in atomically thin ferromagnetic CrI3 trigger new fascinating physics and application perspectives.The physical properties of two-dimensional(2D)ferromagnetism CrI3 are significantly influen...Long-range magnetic orders in atomically thin ferromagnetic CrI3 trigger new fascinating physics and application perspectives.The physical properties of two-dimensional(2D)ferromagnetism CrI3 are significantly influenced by interlayer spacing and stacking order,which are sensitive to the hydrostatic pressure and external environments.However,there remains debate on the stacking order at low temperature.Here,we study the interlayer coupling and stacking order of non-encapsulated 2–5 layer and bulk CrI3 at 10 K by Raman spectroscopy;demonstrate a rhombohedral stacking in both antiferromagnetic and ferromagnetic CrI3.The opposite helicity dependence of Ag and Eg modes arising from phonon symmetry further validates the rhombohedral stacking.An anomalous temperature-dependent behavior is observed due to spin-phonon coupling below 60 K.Our study provides insights into the interlayer coupling and stacking orders of 2D ferromagnetic materials.展开更多
The great success of the Sojourner rover in the Mars Pathfinder mission set off a global upsurge of planetary exploration with autonomous wheeled mobile robots(WMRs),or rovers.Planetary WMRs are among the most intelli...The great success of the Sojourner rover in the Mars Pathfinder mission set off a global upsurge of planetary exploration with autonomous wheeled mobile robots(WMRs),or rovers.Planetary WMRs are among the most intelligent space systems that combine robotic intelligence(robint),virtual intelligence(virtint),and human intelligence(humint) synergetically.This article extends the architecture of the three-layer intelligence stemming from successful Mars rovers and related technologies in order to support the R&D of future tele-operated robotic systems.Double-layer human-machine interfaces are suggested to support the integration of humint from scientists and engineers through supervisory(Mars rovers) or three-dimensional(3D) predictive direct tele-operation(lunar rovers).The concept of multilevel autonomy to realize robint,in particular,the Coupled-Layer Architecture for Robotic Autonomy developed for Mars rovers,is introduced.The challenging issues of intelligent perception(proprioception and exteroception),navigation,and motion control of rovers are discussed,where the terrains' mechanical properties and wheel-terrain interaction mechanics are considered to be key.Double-level virtual simulation architecture to realize virtint is proposed.Key technologies of virtint are summarized:virtual planetary terrain modeling,virtual intelligent rover,and wheel-terrain interaction mechanics.This generalized three-layer intelligence framework is also applicable to other systems that require human intervention,such as space robotic arms,robonauts,unmanned deep-sea vehicles,and rescue robots,particularly when there is considerable time delay.展开更多
基金Supported by the Science Foundation for Post Doctorate of China (20060400629).
文摘The microemulsified acid system composed by diesel oil, hydrochloric acid and emulsifier was investi- gated in this paper. The stability of microemulsified acid and the phase behavior of the microemulsified system Were studied. The size distribution and the corrosion inhibition performance were also observed. The results showed that the diesel oil microemulsified acid system possessed small size and good stability under different temperature.The tolerance to CaCl2 reached 80 g·L^-1. Compared with the same concentration hydrochloric acid solution, the corrosion inhibition performance of the diesel oil microemulsified acid system was remarkable.
基金Supported by the National Natural Science Foundation of China(No.29736180).
文摘The synthesis route was investigated and optimized for the preparation of iminodiacetic acid-polyethylene glycol (IDA-PEG) for immobilized metal ion affinity partitioning in aqueous two-phase systems. IDA-PEG was synthesized from PEG in two steps by the reaction of iminodiacetic acid with a monosubstituted derivative of epichlorohydrin-activated PEG. The Cu2+ content combined with IDA-PEG was determined by atomic absorption spectrometry as 0.5 mol·mol^-1 (PEG). Furthermore, the affinity partitioning behavior of lactate dehydrogenase in polyethylene glycol/hydroxypropyl starch aqueous two-phase systems was studied to clarify the affinity effect of the Cu(Ⅱ)-IDA-PEG.
文摘There has been increasing research in developing offline web applications. This paper concentrates on developing a new methodology for the online assessment web applications that could be used while offline. It is important to retrieve the critical data collected during an examination without a provision of a backup mechanism. There is a need for an assessment system that can adapt to work uninterruptedly and without loss of critical data while there is intermittent intemet discontinuity. This paper describes architecture and implementation of online assessment system with offline capabilities. Online assessment system with offline capabilities will not interrupt examinee's experience while appearing for an assessment test if intemet connection is not available. A development methodology is designed and a compliant framework is implemented to enhance online assessment system with offline capabilities.
基金Project(2006BAE02B05) supported by the Key Projects in the National Science and Technology Pillar Program During the 11th Five-year Plan PeriodProject(2005CB221406) supported by the National Basic Research Program of China
文摘A new reaction system was designed to economically convert glucose to lactic acid environment-friendly. Hydrophobic ionic liquids were chosen as solvent that can promote the decomposition reaction of glucose, and the catalytic performance of the solid bases was evaluated. Both the reaction temperature and time can affect the yield of lactic acid. A high yield (97%) of lactic acid was achieved under the optimal reaction condition. The IH NMR spectra and HPLC-MS were used to identify the formation of the lactic acid and variations of ionic liquid. It is found that ionic-liquids have a unique solvent effect for glucose and bases. Water can be used as solvent to extract calcium lactate. This shows a great potential of hydrophobic ionic liquids in the solid bases catalyzed reaction that is limited by the weak solubility of solid bases in organic and water solution.
基金Supported by the National Natural Science Foundation of China(No.29676069).
文摘In the established apparatus, the conversion ratios of cellulose sulfation (X) under different sulfation conditions were measured. The range of temperature was from -5℃ to +5℃, and the H2SO4 concentration was from 3.1 mol·L-1 to 4.5mol·L-1. The experimental results were used for the establishment of the kinetic model for cellulose sulfation. With the model, X values and the yield of NaCS (Y) can be calculated, thus the reaction with respect to H2SO4 concentration is determined to be third order.
基金the National Science and Technology Major Project of China(Grant No.2011ZX05025-003-007)the 135 program of Chinese Academy of Sciences(Grant No.GIGCAS-135Y234151001)
文摘Noble and active gases are released from geological samples during gas extraction for noble gas isotope analyses. The active gases should be removed before inletting to mass spectrometers for the analyses. The normal noble gas preparation systems can clean up most geological samples. However, authigenic minerals from sedimentary rocks in oil/gas fields contain organic matter, which cannot be cleaned up by the normal preparation systems and thus influence the noble gas analyses. We introduce a novel gas purification system (PRC patent No. ZL201320117751.2), which includes several reversible purification pumps with different absorbing and degassing temperatures. It can well clean up water steam, carbon dioxide and organic gas- es. Mica minerals are often used for 40Ar/39Ar dating. A muscovite sample (2082MS) which could not be cleaned up by the normal preparation system with two SAES NP10 getters, becomes the test sample for a comparative experiment in this study. The experiment is assigned into 4 sections with the organic gas removal system (OGRS) "Closed/Opened" in turn. When the OGRS is closed only with two NP10 getters for purification, the 40At intensities increase in curves with inlet time because of impurities, the 40Ar/39Ar dating results yield age errors about +2%-±1% (20-). When the OGRS is opened for purification, in contrast, the 40Ar intensities decrease linearly with inlet time. This indicates that the gases have been cleaned up effectively, and the 40Ar/39Ar results yield ages with errors in ±0.4%. The OGRS is very helpful to obtain high-quality analysis data.
基金the financial support from the National Natural Science Foundation of China (51602040 and 51872039)the Science and Technology Program of Sichuan (M112018JY0025)the Scientific Research Foundation for New Teachers of UESTC (A03013023601007)
文摘Long-range magnetic orders in atomically thin ferromagnetic CrI3 trigger new fascinating physics and application perspectives.The physical properties of two-dimensional(2D)ferromagnetism CrI3 are significantly influenced by interlayer spacing and stacking order,which are sensitive to the hydrostatic pressure and external environments.However,there remains debate on the stacking order at low temperature.Here,we study the interlayer coupling and stacking order of non-encapsulated 2–5 layer and bulk CrI3 at 10 K by Raman spectroscopy;demonstrate a rhombohedral stacking in both antiferromagnetic and ferromagnetic CrI3.The opposite helicity dependence of Ag and Eg modes arising from phonon symmetry further validates the rhombohedral stacking.An anomalous temperature-dependent behavior is observed due to spin-phonon coupling below 60 K.Our study provides insights into the interlayer coupling and stacking orders of 2D ferromagnetic materials.
基金supported by the National Natural Science Foundation of China(Grant No.61370033)National Basic Research Program of China(Grant No.2013CB035502)+4 种基金Foundation of Chinese State Key Laboratory of Robotics and Systems(Grant Nos.SKLRS201401A01,SKLRS-2014-MS-06)the Fundamental Research Funds for the Central Universities(Grant No.HIT.BRETIII.201411)Harbin Talent Programme for Distinguished Young Scholars(No.2014RFYXJ001)Postdoctoral Youth Talent Foundation of Heilongjiang Province,China(Grant No.LBH-TZ0403)the"111 Project"(Grant No.B07018)
文摘The great success of the Sojourner rover in the Mars Pathfinder mission set off a global upsurge of planetary exploration with autonomous wheeled mobile robots(WMRs),or rovers.Planetary WMRs are among the most intelligent space systems that combine robotic intelligence(robint),virtual intelligence(virtint),and human intelligence(humint) synergetically.This article extends the architecture of the three-layer intelligence stemming from successful Mars rovers and related technologies in order to support the R&D of future tele-operated robotic systems.Double-layer human-machine interfaces are suggested to support the integration of humint from scientists and engineers through supervisory(Mars rovers) or three-dimensional(3D) predictive direct tele-operation(lunar rovers).The concept of multilevel autonomy to realize robint,in particular,the Coupled-Layer Architecture for Robotic Autonomy developed for Mars rovers,is introduced.The challenging issues of intelligent perception(proprioception and exteroception),navigation,and motion control of rovers are discussed,where the terrains' mechanical properties and wheel-terrain interaction mechanics are considered to be key.Double-level virtual simulation architecture to realize virtint is proposed.Key technologies of virtint are summarized:virtual planetary terrain modeling,virtual intelligent rover,and wheel-terrain interaction mechanics.This generalized three-layer intelligence framework is also applicable to other systems that require human intervention,such as space robotic arms,robonauts,unmanned deep-sea vehicles,and rescue robots,particularly when there is considerable time delay.