[Objective] The aim was to get optimized conditions for date powder with good color and taste.[Method] The pectinase enzymolysis and vacuum freeze-drying technology were used in the extract process of date powder.[Res...[Objective] The aim was to get optimized conditions for date powder with good color and taste.[Method] The pectinase enzymolysis and vacuum freeze-drying technology were used in the extract process of date powder.[Result] The production boasts of superior quality were with rich fragrance and uniform particle under certain process conditions.The optimized conditions for pectinase enzymolysis were:the amount of pectinase reached to 0.1% of that of date syrup,enzymolysis temperature and time were 50 ℃ and 50 min respectively,the pH value was 4.0.The optimized conditions for vaccum freeze-drying were:10% altodextrin,three times volumn of water with the thickness of 7 mm.[Conclusion] The optimized conditions were obtained in this study to produce instant date powder from Ziziphus jujuba.展开更多
Manufacturing process,diffusion co-efficient and areal capacity are the three main criteria for regulating thick electrodes for lithium-ion batteries(LIBs).However,simultaneously regulating these criteria for LIBs is ...Manufacturing process,diffusion co-efficient and areal capacity are the three main criteria for regulating thick electrodes for lithium-ion batteries(LIBs).However,simultaneously regulating these criteria for LIBs is desirable but remains a significant challenge.In this work,niobium pentoxide(Nb_(2)O_(5))anode and lithium iron phosphate(LiFePO_(4))cathode materials were chosen as the model materials and demonstrate that these three parameters can be simultaneously modulated by incorporation of micro-carbon fibers(MCF)and carbon nanotubes(CNT)with both Nb_(2)O_(5) and LFP via vacuum filtration approach.Both as-prepared MNC-20 anode and MLC-20 cathode achieves high reversible areal capacity of≈5.4 m A h cm^(-2)@0.1 C and outstanding Li-ion diffusion coefficients of≈10~(-8)cm~2 s~(-1)in the half-cell configuration.The assembled MNC-20‖MLC-20 full cell LIB delivers maximum energy and power densities of244.04 W h kg^(-1)and 108.86 W kg^(-1),respectively.The excellent electrochemical properties of the asprepared thick electrodes can be attributed to the highly conductive,mechanical compactness and multidimensional mutual effects of the MCF,CNT and active materials that facilitates rapid Li-ion diffusion kinetics.Furthermore,electrochemical impedance spectroscopy(EIS),symmetric cells analysis,and insitu Raman techniques clearly validates the enhanced Li-ion diffusion kinetics in the present architecture.展开更多
The ZrO2 ceranfic was successfully jointed to stainless steel by vacuum brazing with active filler metal. The AgCuTi active filler metal was used and the joining was performed at a temperature of 850 ℃ for 10 rain. T...The ZrO2 ceranfic was successfully jointed to stainless steel by vacuum brazing with active filler metal. The AgCuTi active filler metal was used and the joining was performed at a temperature of 850 ℃ for 10 rain. The microstructures of the joints were characterized by metallographic microscopy, scanning electron microscopy （SEM）, and energy dispersive spectroscopy （EDS）. Metallographic microscopy analysis shows that the morphology of the cross section was a sandwich structure and the TiO is observed in the surface of ZrO2/ stainless steel. The diffusion and enrichment of the elements are the key roles in the brazing of ZrO2 ceramic and stainless steel. The formation of TiCu compounds inhibited the further diffusion of titanium into stainless steel or the ZrO2 ceramic to form TiO compound. In the experimental conditions, the average tensile strength is 80MPa for the joint of ZrO2 ceramic / AgCuTi/ stainless steel systems. A complete joint is formed between the ZrO2 ceramic and stainless steel with the leakage rate at the degree of 10 ^-12 Pa · m^3/s.展开更多
The free shrinkage of ceramic or metal is restricted due to solidification of the solder. Hence the shrinkage stress arises and the jointing strength is reduced during the brazing of high-voltage vacuum interrupters ...The free shrinkage of ceramic or metal is restricted due to solidification of the solder. Hence the shrinkage stress arises and the jointing strength is reduced during the brazing of high-voltage vacuum interrupters （HVVIs）. The solder bound contour was gained by solved energy bound equation. The finite element model of weld beads was established with Surface Evolver software. Then the stress in two different cooling techniques （ natural cooling and force cooling） was calculated with ANSYS. Comparing the stress, a better cooling technique was selected for HVVIs. Its cooling time is shortened by 3 hours while the jointing stress doesn＇ t increase and the tensile strength of ceramic to metal seal is not decreased. The stress-rupture tests have validated the calculated results. More important, a method is found, by which the brazing technique could be improved in advance instead of blind experiments.展开更多
Based on the Husimi operator in pure state form introduced by Fan et al,which is a squeezed coherentstate projector,and the technique of integration within an ordered product (IWOP) of operators,as well as the entangl...Based on the Husimi operator in pure state form introduced by Fan et al,which is a squeezed coherentstate projector,and the technique of integration within an ordered product (IWOP) of operators,as well as the entangledstate representations,we obtain the Husimi functions of the excited squeezed vacuum states (ESVS) and two marginaldistributions of the Husimi functions of the ESVS.展开更多
Jetting succeeded by accumulation is the characteristic of the vacuum filling,which is different from the conventional pressure-driven flow.In order to simulate this kind of flow,a three-dimensional theoretical model ...Jetting succeeded by accumulation is the characteristic of the vacuum filling,which is different from the conventional pressure-driven flow.In order to simulate this kind of flow,a three-dimensional theoretical model in terms of incompressible and viscous flow is established,and an iterative method combined with finite element method(FEM)is proposed to solve the flow problem.The Lagranian-VOF method is constructed to trace the jetting and accumulated flow fronts.Based on the proposed model and algorithm,a simulation program is developed to predict the velocity,pressure,temperature,and advancement progress.To validate the model and algorithm,a visual experimental equipment for vacuum filling is designed and construted.The vacuum filling experiments with different viscous materials and negative pressures were conducted and compared with the corresponding simulations.The results show the flow front shape closely depends on the fluid viscosity and less relates to the vacuum pressure.展开更多
Conventional mechanical method and mechanical method combined with vacuum freeze-drying technology were used to make the ultra-fine powders of edible fungus (Auricularia auricular). The content of basic nutrients, ami...Conventional mechanical method and mechanical method combined with vacuum freeze-drying technology were used to make the ultra-fine powders of edible fungus (Auricularia auricular). The content of basic nutrients, amino acid, micro structure and their properties of raw edible fungus and the edible fungus powders obtained with the two methods were analyzed and compared. The granularity size and micro-structure of the pulverized samples were analyzed by SEM and TEM technology. The average granularity size of the edible fungus powder obtained with mechanical method was 1–5 μm, while that obtained with mechanical method combined with vacuum freeze-drying process was 0.5–1 μm. The ultra-fine powders of edible fungus obtained with the two methods had better water recovery capability and quality, and their preserving time was longer than that of raw edible fungus. All the properties of the ultra-fine powders of edible fungus obtained with the vacuum freeze-drying technology were evidently superior to that of the conventional mechanical method. Keywords Auricularia auricula - Edible fungus - Ultra-fine powders - Vacuum freeze-drying CLC number TS205 Document code B Biography: YANG Chun-yu (1975), female, Ph. D. in Engineering Technology Center of Forestry and Wood Workine, Machinery, Northeast Forestry University, Harbin 150040, P. R. China.Responsible editor: Zhu Hong展开更多
基金Supported by Key Projects of Henan Institute of Science and Technology (06013)
文摘[Objective] The aim was to get optimized conditions for date powder with good color and taste.[Method] The pectinase enzymolysis and vacuum freeze-drying technology were used in the extract process of date powder.[Result] The production boasts of superior quality were with rich fragrance and uniform particle under certain process conditions.The optimized conditions for pectinase enzymolysis were:the amount of pectinase reached to 0.1% of that of date syrup,enzymolysis temperature and time were 50 ℃ and 50 min respectively,the pH value was 4.0.The optimized conditions for vaccum freeze-drying were:10% altodextrin,three times volumn of water with the thickness of 7 mm.[Conclusion] The optimized conditions were obtained in this study to produce instant date powder from Ziziphus jujuba.
基金supported by the Science and Technology Innovation Program of Hunan Province(2022WZ1012)the Hunan Joint International Laboratory of Advanced Materials and Technology for Clean Energy(2020CB1007)the Natural Science Foundation of Guangzhou(202201020147)。
文摘Manufacturing process,diffusion co-efficient and areal capacity are the three main criteria for regulating thick electrodes for lithium-ion batteries(LIBs).However,simultaneously regulating these criteria for LIBs is desirable but remains a significant challenge.In this work,niobium pentoxide(Nb_(2)O_(5))anode and lithium iron phosphate(LiFePO_(4))cathode materials were chosen as the model materials and demonstrate that these three parameters can be simultaneously modulated by incorporation of micro-carbon fibers(MCF)and carbon nanotubes(CNT)with both Nb_(2)O_(5) and LFP via vacuum filtration approach.Both as-prepared MNC-20 anode and MLC-20 cathode achieves high reversible areal capacity of≈5.4 m A h cm^(-2)@0.1 C and outstanding Li-ion diffusion coefficients of≈10~(-8)cm~2 s~(-1)in the half-cell configuration.The assembled MNC-20‖MLC-20 full cell LIB delivers maximum energy and power densities of244.04 W h kg^(-1)and 108.86 W kg^(-1),respectively.The excellent electrochemical properties of the asprepared thick electrodes can be attributed to the highly conductive,mechanical compactness and multidimensional mutual effects of the MCF,CNT and active materials that facilitates rapid Li-ion diffusion kinetics.Furthermore,electrochemical impedance spectroscopy(EIS),symmetric cells analysis,and insitu Raman techniques clearly validates the enhanced Li-ion diffusion kinetics in the present architecture.
基金supported by the National Key R&D Program of China(Grant No.2017YFB0305700)
文摘The ZrO2 ceranfic was successfully jointed to stainless steel by vacuum brazing with active filler metal. The AgCuTi active filler metal was used and the joining was performed at a temperature of 850 ℃ for 10 rain. The microstructures of the joints were characterized by metallographic microscopy, scanning electron microscopy （SEM）, and energy dispersive spectroscopy （EDS）. Metallographic microscopy analysis shows that the morphology of the cross section was a sandwich structure and the TiO is observed in the surface of ZrO2/ stainless steel. The diffusion and enrichment of the elements are the key roles in the brazing of ZrO2 ceramic and stainless steel. The formation of TiCu compounds inhibited the further diffusion of titanium into stainless steel or the ZrO2 ceramic to form TiO compound. In the experimental conditions, the average tensile strength is 80MPa for the joint of ZrO2 ceramic / AgCuTi/ stainless steel systems. A complete joint is formed between the ZrO2 ceramic and stainless steel with the leakage rate at the degree of 10 ^-12 Pa · m^3/s.
基金Sponsored by the National Natural Science Foundation of China(50377003).
文摘The free shrinkage of ceramic or metal is restricted due to solidification of the solder. Hence the shrinkage stress arises and the jointing strength is reduced during the brazing of high-voltage vacuum interrupters （HVVIs）. The solder bound contour was gained by solved energy bound equation. The finite element model of weld beads was established with Surface Evolver software. Then the stress in two different cooling techniques （ natural cooling and force cooling） was calculated with ANSYS. Comparing the stress, a better cooling technique was selected for HVVIs. Its cooling time is shortened by 3 hours while the jointing stress doesn＇ t increase and the tensile strength of ceramic to metal seal is not decreased. The stress-rupture tests have validated the calculated results. More important, a method is found, by which the brazing technique could be improved in advance instead of blind experiments.
基金Supported by National Natural Science Foundation of China under Grant No.10574060Shandong Province of China under Grant No.Y2008A23Liaocheng University of China under Grant No.X071049
文摘Based on the Husimi operator in pure state form introduced by Fan et al,which is a squeezed coherentstate projector,and the technique of integration within an ordered product (IWOP) of operators,as well as the entangledstate representations,we obtain the Husimi functions of the excited squeezed vacuum states (ESVS) and two marginaldistributions of the Husimi functions of the ESVS.
基金the National Science Foundation of China(No.11672271)Shenzhen Zhaowei Machinery&Electronics CO.,LTD.(No.20210035A and 20210035B)for this research work are gratefully acknowledged.
文摘Jetting succeeded by accumulation is the characteristic of the vacuum filling,which is different from the conventional pressure-driven flow.In order to simulate this kind of flow,a three-dimensional theoretical model in terms of incompressible and viscous flow is established,and an iterative method combined with finite element method(FEM)is proposed to solve the flow problem.The Lagranian-VOF method is constructed to trace the jetting and accumulated flow fronts.Based on the proposed model and algorithm,a simulation program is developed to predict the velocity,pressure,temperature,and advancement progress.To validate the model and algorithm,a visual experimental equipment for vacuum filling is designed and construted.The vacuum filling experiments with different viscous materials and negative pressures were conducted and compared with the corresponding simulations.The results show the flow front shape closely depends on the fluid viscosity and less relates to the vacuum pressure.
文摘Conventional mechanical method and mechanical method combined with vacuum freeze-drying technology were used to make the ultra-fine powders of edible fungus (Auricularia auricular). The content of basic nutrients, amino acid, micro structure and their properties of raw edible fungus and the edible fungus powders obtained with the two methods were analyzed and compared. The granularity size and micro-structure of the pulverized samples were analyzed by SEM and TEM technology. The average granularity size of the edible fungus powder obtained with mechanical method was 1–5 μm, while that obtained with mechanical method combined with vacuum freeze-drying process was 0.5–1 μm. The ultra-fine powders of edible fungus obtained with the two methods had better water recovery capability and quality, and their preserving time was longer than that of raw edible fungus. All the properties of the ultra-fine powders of edible fungus obtained with the vacuum freeze-drying technology were evidently superior to that of the conventional mechanical method. Keywords Auricularia auricula - Edible fungus - Ultra-fine powders - Vacuum freeze-drying CLC number TS205 Document code B Biography: YANG Chun-yu (1975), female, Ph. D. in Engineering Technology Center of Forestry and Wood Workine, Machinery, Northeast Forestry University, Harbin 150040, P. R. China.Responsible editor: Zhu Hong
