A pioneering glass-compatible transparent temperature alarm system self-powered by luminescent solar concentrators(LSCs) is reported.Single green-emitted organic manganese halides(OMHs) of PEA_(2)MnBr_(2)I_(2),which h...A pioneering glass-compatible transparent temperature alarm system self-powered by luminescent solar concentrators(LSCs) is reported.Single green-emitted organic manganese halides(OMHs) of PEA_(2)MnBr_(2)I_(2),which has a unique temperature-dependent backward energy transfer process from selftrapped state to^(4)T_(1)energy level of Mn,is used for triggering the temperature alarm.The LSC with redemitted CsPbI_(3)perovskite-polymer composite films on the glass substrate is used for power supply.The spectrally separated nature between the green-emitted OMHs for temperature alarm and red-emitted CsPbI3in LSC for power supply allows for probing the signal light of temperature-responsive OMHs without the interference of LSCs,making it possible to calibrate the temperature visually just by a self-powered brightness detection circuit with LED indicators.Taking advantage of LSC without hot spot effects plaguing the solar cells,as-prepared temperature alarm system can operate well on both sunny and cloudy day.展开更多
The energy-transfer process between sodium (omega-[2-(alpha -naphthyl)ethoxy]undecanoate (FP-)* and sodium omega -9-anthrylmethyl glutarate (AFP(-)) is accelerated by the formation of ESAg when cetyltrimethylammonium ...The energy-transfer process between sodium (omega-[2-(alpha -naphthyl)ethoxy]undecanoate (FP-)* and sodium omega -9-anthrylmethyl glutarate (AFP(-)) is accelerated by the formation of ESAg when cetyltrimethylammonium chloride (S16(+)) has been added to the solvent system of FP-* and AFP(-). This result is yet another evidence for the formation of ESAg.展开更多
Based on investigation data of PHC content in Jiaozhou Bay,China from 1979 to 1983,the seasonal variations of PHC content and monthly changes of precipitation in Jiaozhou Bay were analyzed. The results showed that see...Based on investigation data of PHC content in Jiaozhou Bay,China from 1979 to 1983,the seasonal variations of PHC content and monthly changes of precipitation in Jiaozhou Bay were analyzed. The results showed that seen from the spatial and temporal distribution,the seasonal variation of PHC content in the surface water of Jiaozhou Bay was based on the flow of the rivers as well as human activity,so PHC content in the rivers depended on the flow of the rivers and human activity,and the peaks and valleys of PHC content appeared in various seasons. The seasonal variation of PHC content in the surface water of Jiaozhou Bay depended on its land transfer process. The land transfer process was composed of use of PHC by mankind,deposition of PHC in soil and on the earth's surface,and transportation of PHC to offshore waters of sea by rivers and surface runoff. PHC content depended on mankind during the process from being used to entering soil and on precipitation during the process of being transported from soil to ocean.展开更多
This paper investigates the thermal-coupled effect across the wall and the optimal heat transfer region of the wall for enhancing the energy saving effect of dividing wall column (DWC), and also studies the effects of...This paper investigates the thermal-coupled effect across the wall and the optimal heat transfer region of the wall for enhancing the energy saving effect of dividing wall column (DWC), and also studies the effects of feed thermal condition (q) and middle component composition of feed (cB) on the heat transfer process, the optimal heat transfer region, and the maximum heat transfer quantity across the wall. The simulation results show that the maximum heat transfer quantity across the wall and the potential for energy saving increase with the increase of q, while with the limitation of temperature difference across the wall, the beneficial heat transfer effect between certain range of stages, which are involved in the optimal heat transfer region, cannot be realized completely for a specific value of q. Besides, compared with q, a changing cB does not change the degree of realizing the beneficial heat transfer effect, but can bring about the variation of liquid split ratio (RL) and vapor split ratio (Rv). Thus, for achieving a maximum energy-saving effect of DWC, different q and cB need to find its own corresponding suitable heat transfer process across the wall.展开更多
Based on the investigation data of PHC content in Jiaozhou Bay,China during 1980-1981,the vertical distribution of PHC content in the water of Jiaozhou Bay was analyzed.The results showed that from 1980 to 1981,the ve...Based on the investigation data of PHC content in Jiaozhou Bay,China during 1980-1981,the vertical distribution of PHC content in the water of Jiaozhou Bay was analyzed.The results showed that from 1980 to 1981,the vertical distribution of PHC content in the water of Jiaozhou Bay depended on the water transfer process of PHC.During the water transfer process of PHC,PHC was input from pollution sources into the surface water of the bay firstly,and then it settled to the bottom.The horizontal distribution trends of PHC content in the surface and bottom water,the changes of PHC content in the surface and bottom water,and the vertical changes of PHC content showed that the settlement of PHC was fast and was consistent with PHC content.PHC accumulated at the bottom after continuous settlement of PHC,which revealed the water transfer process of PHC in Jiaozhou Bay.展开更多
The coupled heat and moisture transfer in a freezing process of wood particle material was mathematically modeled in the paper. The models were interactively solved by using the numerical method(the finite element met...The coupled heat and moisture transfer in a freezing process of wood particle material was mathematically modeled in the paper. The models were interactively solved by using the numerical method(the finite element method and the finite difference method). By matching the theoretical calculation to an experiment, the nonlinear problem was analyzed and the variable thermophysical parameters concerned was evaluated. The analysis procedure and the evaluation of the parameters were presented in detail. The result of the study showed that by using the method as described in the paper, it was possible to determine the variable (with respect to temperature, moisture content and freezing state) thermophysical parameters which were unknown or difficult to measure as long as the governing equations for a considered process were available. The method can significantly reduces the experiment efforts for determining thermophysical parameters which arc very complicated to measure. The determined variable of the effective heat conductivity of wood particle material was given in the paper. The error of the numerical calculation was also estimated by the comparison with a matched experiment.展开更多
The processes of heat and humidity transfer between air and water are what to be studied mainly in the paper, we put forward some main factors which influence the processes of heat and humidity transfer in the air was...The processes of heat and humidity transfer between air and water are what to be studied mainly in the paper, we put forward some main factors which influence the processes of heat and humidity transfer in the air washer. We come to the conclusion that we can change these main factors to achieve different heat and humidity transfer processes and decide processes of heat and humidity transfer of air and water with the initial temperature of spraying water in the air washer. All these results can make things convenient for the air conditioning management.展开更多
The article focuses on a theoretical and experimental framework for the quantification of interaction between nonlinear geomechnical and physicochemical processes in high-stress coal-bearing rock mass during mining un...The article focuses on a theoretical and experimental framework for the quantification of interaction between nonlinear geomechnical and physicochemical processes in high-stress coal-bearing rock mass during mining under high seismic risk due to large-scale blasting and earthquakes,as well as because of structural and temperature effects.The tests were aimed to examine and study comprehensively the piston mechanism of gas exchange and mass transfer processes,revealed recently at the Institute of Mining,SB RAS,as well as to explain the fact that the earthquake-induced low-velocity(quasi-meter range)pendulum waves(velocity to 1 m/s and frequency of 0.5–5 Hz)could stimulate an increase in the gas content in coal mines.In order to perform laboratory investigation at the Institute of Mining SB RAS,special-purpose stand for analyzing gas exchange and mass transfer processes in coal-bearing geomaterials under various thermodynamic conditions(P,V,T)and gas composition was constructed in cooperation with the Institute of Semiconductors Physics SB RAS.Matching of air flow rate with compression pressures allowed to obtain relations showing that air flow rate increases at the uncertain time interval under the increasing of the compression pressure.The same measurements was carried out with another gases such as Hydrogen H_(2),Helium He,methane CH_(4),carbon dioxide CO_(2) and carbon oxide CO.The laboratory tests aimed to detailed investigation of the previously revealed“piston mechanism”of gas exchange and mass transfer processes in the coal specimens and their quantitative description in terms of theory of the pendulum waves were carried in the first time.Consequently,there are some arguments for the testing of the opportunity of quantitative description of the“piston mechanism”related to gas exchange and mass transfer processes in the scale of coal mines.It is relevant when pendulum waves induced by powerful earthquakes and technical blasting reaches the mine.展开更多
Nonylphenol(NP)residues,as a typical endocrine disrupting chemical(EDC),frequently exist in sewage,surface water,groundwater and even drinking water,which poses a serious threat to human health due to its bioaccumulat...Nonylphenol(NP)residues,as a typical endocrine disrupting chemical(EDC),frequently exist in sewage,surface water,groundwater and even drinking water,which poses a serious threat to human health due to its bioaccumulation.In order to remove NP,a series of MIL-100(Fe)/Zn Fe_(2)O_(4)/flake-like porous carbon nitride(MIL/ZC)was synthesized through in-situ synthesis at room temperature.High performance of ternary MIL/ZC is used to degrade NP under visible light irradiation.The results show that 30MIL/ZC2(20 wt.%Zn Fe_(2)O_(4))ternary composite had the best photocatalytic activity(99.84%)when the dosage was 30 mg.Further mechanism analysis shows that the excellent photocatalytic activity of 30MIL/ZC2could be ascribed to the double charge transfer process between flake-like porous carbon nitride(PCN)and other catalysts in the ternary heterojunction,and the separation of photogenerated electron-hole pairs was more effective.In addition,the 30MIL/ZC2 also showed high stability after five cycles of the photodegradation reaction.Furthermore,the active substance(·O_(2)^(-))was considered to be the main active substance in the NP degradation process.Based on the research results,the possible photocatalytic reaction mechanism of 30MIL/ZC2ternary composite was proposed and discussed in detail.展开更多
A numerical model is proposed to analyze mass, momentum, and energy transfer between plasma andparticles in d.c. arc-heated and confined jet reactors at atmospheric pressure. It emphasizes the phasechange and thermal ...A numerical model is proposed to analyze mass, momentum, and energy transfer between plasma andparticles in d.c. arc-heated and confined jet reactors at atmospheric pressure. It emphasizes the phasechange and thermal chemistry of particles and includes some other effects such as flow turbulence, gascompressibility and temperature-dependence of the transport properties under the plasma condition.Example calculations for plasma-dissociated zircon process indicate the influences of reactor operationparameters on the plasma jet and particle behavior.展开更多
According to heat transfer principle and the process of solving engineering problems by finite element method, examples were given to demonstrate how finite element analysis can be used to describe transient heat tran...According to heat transfer principle and the process of solving engineering problems by finite element method, examples were given to demonstrate how finite element analysis can be used to describe transient heat transfer through fabrics. Details were given to describe how conduction and convection affect temperature distribution and heat loss during heat transfer processes by taking advantage of the quick calculation of FEA software MSC.Marc. Experimental results show good agreement with the theoretical results.展开更多
A 3-D mathematical model considering turbulence phenomena has been established based on a computational fluid dynamics technique, so called 3-D SOLA-VOF (Solution Algorithm-Volume of Fluid), to simulate the fluid flow...A 3-D mathematical model considering turbulence phenomena has been established based on a computational fluid dynamics technique, so called 3-D SOLA-VOF (Solution Algorithm-Volume of Fluid), to simulate the fluid flow of mold filling process of die casting. In addition, the mathematical model for simulating the heat transfer in die casting process has also been established. The computation program has been developed by the authors with the finite difference method (FDM) recently. As verification, the mold filling process of a S-shaped die casting has been simulated and the simulation results coincide with that of the benchmark test. Finally, as a practical application, the gating design of a motorcycle component was modified by the mold filling simulation and the dies design of another motorcycle component was optimized by the heat transfer simulation. All the optimized designs were verified by the production practice.展开更多
Interfacial charge transfer kinetics of the nanocrystalline CdSe thin film electrodes have been studied in sodium polysulfide solutions by intensity modulated photocurrent spectroscopy (IMPS). The interfacial direct a...Interfacial charge transfer kinetics of the nanocrystalline CdSe thin film electrodes have been studied in sodium polysulfide solutions by intensity modulated photocurrent spectroscopy (IMPS). The interfacial direct and indirect charge transfer and recombination processes were analyzed in terms of the parameters: normalized steady state photocurrents and surface state lifetimes obtained by measuring the IMPS responses under different applied potentials and different solution concentrations. IMPS responses of polycrystalline CdSe thin film electrodes were also presented for comparison.展开更多
Gas hydrates formation and dissociation processes inside porous media are always accompanied by water transfer behavior, which is similar to the water behavior of ice freezing and thawing processes. These processes ha...Gas hydrates formation and dissociation processes inside porous media are always accompanied by water transfer behavior, which is similar to the water behavior of ice freezing and thawing processes. These processes have been studied by many researchers, but all the studies are so far on the water transfer characteristics outside porous media and the water transfer characteristics inside porous media have been little known. In this study, in order to study the water transfer characteristics inside porous media during methane hydrate formation and dissociation processes, a novel apparatus with three pF-meter sensors which can detect water content changes inside porous media was applied. It was experimentally observed that methane hydrate formation processes were accompanied by water transfer from bottom to top inside porous media, however, the water behavior during hydrate dissociation processes was abnormal, for which more studies are needed to find out the real reason in our future work.展开更多
The electrical resistance-pressure strain sensitivity of carbon nanotube network (NTN)/polymer composite is investigated. In this research, polydimethylsiloxane (PDMS) is used as the polymer matrix. The composite of N...The electrical resistance-pressure strain sensitivity of carbon nanotube network (NTN)/polymer composite is investigated. In this research, polydimethylsiloxane (PDMS) is used as the polymer matrix. The composite of NTN embedded in PDMS matrix has been fabricated by using filtration and transfer process. The thickness of NTN/PDMS composite can be controlled. Electrical re- sistance and pressure strain of the NTN/PDMS composite are measured simultaneously. Electrical resistance of NTN/PDMS composite has been obtained as a function of pressure strain. The NTN/PDMS composite exhibits linear change in electrical re- sistance as a result of pressure strain and has improved electrical resistance-pressure strain sensitivity. The NTN/PDMS composite has 90.6% resistance change at 6% pressure strain. The electrical resistance-pressure strain sensitivity of NTN/PDMS composite using filtration and transfer process is 2.13 times of the traditional NTN/PDMS composite. The characteristic in electrical resis- tance change implies that NTN/PDMS composite can be used as pressure strain sensors and applied to sensor systems.展开更多
The concept of process intensification(PI) has absorbed diverse definitions and stays true to the mission—'do more with less', which is an approach purposed by chemical engineers to solve the global energy &a...The concept of process intensification(PI) has absorbed diverse definitions and stays true to the mission—'do more with less', which is an approach purposed by chemical engineers to solve the global energy & environment problems. To date, the focus of PI has been on processes mainly involving vapor/liquid systems. Based on the fundamental principles of vapor–liquid mass transfer process like distillation and absorption, there are three strategies to intensify interphase mass transfer: enhancing the overall driving force, improving the mass transfer coefficient and enlarging the vapor–liquid interfacial area. More specifically, this article herein provides an overview of various technologies to strengthen the vapor–liquid mass transfer, including application of external fields, addition of third substances, micro-chemical technology and usage of solid foam, with the objective to contribute to the future developments and potential applications of PI in scientific research and industrial sectors.展开更多
In this work, the in-situ TiC panicles reinforced composite coating was prepared by plasma transferred arc process on the surface of Q235 steel. Microstructures, phase composition and wear property of the coating were...In this work, the in-situ TiC panicles reinforced composite coating was prepared by plasma transferred arc process on the surface of Q235 steel. Microstructures, phase composition and wear property of the coating were investigated. The results showed that the composite coating consisted mainly of T-Ni, TiC, Cr23C6, Cr7C3, Ni3Si, CrB, Cr5B3 and FeNi3 phases, and was characterized by fine TiC panicles embedded in Ni matrix. The wear resistance of composite coating was significantly improved compared with that of the steel substrate. The wear volume loss of the substrate was 443 mm3, which was about 9 times as that of in-situ TiC particles reinforced composite coating (49 mm3 ). It is mainly attributed to the presence of chromium carbide particles and in-situ TiC particles and their favorable combination with Ni matrix.展开更多
In order to study water transfer characteristics inside non-saturated media during methane hydrate formation and dissociation processes,water changes on the top,middle and bottom locations of experimental media during...In order to study water transfer characteristics inside non-saturated media during methane hydrate formation and dissociation processes,water changes on the top,middle and bottom locations of experimental media during the reaction processes were continuously followed with a novel apparatus with three pF-meter sensors.Coarse sand,fine sand and loess were chosen as experimental media.It was experimentally observed that methane hydrate was easier formed inside coarse sand and fine sand than inside loess.Methane hydrate formation configuration and water transfer characteristics during methane hydrate formation processes were very different among the different non-saturated media,which were important for understanding methane hydrate formation and dissociation mechanism inside sediments in nature.展开更多
Fault diagnosis is an important measure to ensure the safety of production, and all kinds of fault diagnosis methods are of importance in actual production process. However, the complexity and uncertainty of productio...Fault diagnosis is an important measure to ensure the safety of production, and all kinds of fault diagnosis methods are of importance in actual production process. However, the complexity and uncertainty of production process often lead to the changes of data distribution and the emergence of new fault classes, and the number of the new fault classes is unpredictable. The reconstruction of the fault diagnosis model and the identification of new fault classes have become core issues under the circumstances. This paper presents a fault diagnosis method based on model transfer learning and the main contributions of the paper are as follows: 1) An incremental model transfer fault diagnosis method is proposed to reconstruct the new process diagnosis model. 2) Breaking the limit of existing method that the new process can only have one more class of faults than the old process, this method can identify M faults more in the new process with the thought of incremental learning. 3) The method offers a solution to a series of problems caused by the increase of fault classes. Experiments based on Tennessee-Eastman process and ore grinding classification process demonstrate the effectiveness and the feasibility of the method.展开更多
基金supported by the Natural Science Foundation of China(22075043,21875034,61704093)。
文摘A pioneering glass-compatible transparent temperature alarm system self-powered by luminescent solar concentrators(LSCs) is reported.Single green-emitted organic manganese halides(OMHs) of PEA_(2)MnBr_(2)I_(2),which has a unique temperature-dependent backward energy transfer process from selftrapped state to^(4)T_(1)energy level of Mn,is used for triggering the temperature alarm.The LSC with redemitted CsPbI_(3)perovskite-polymer composite films on the glass substrate is used for power supply.The spectrally separated nature between the green-emitted OMHs for temperature alarm and red-emitted CsPbI3in LSC for power supply allows for probing the signal light of temperature-responsive OMHs without the interference of LSCs,making it possible to calibrate the temperature visually just by a self-powered brightness detection circuit with LED indicators.Taking advantage of LSC without hot spot effects plaguing the solar cells,as-prepared temperature alarm system can operate well on both sunny and cloudy day.
文摘The energy-transfer process between sodium (omega-[2-(alpha -naphthyl)ethoxy]undecanoate (FP-)* and sodium omega -9-anthrylmethyl glutarate (AFP(-)) is accelerated by the formation of ESAg when cetyltrimethylammonium chloride (S16(+)) has been added to the solvent system of FP-* and AFP(-). This result is yet another evidence for the formation of ESAg.
文摘Based on investigation data of PHC content in Jiaozhou Bay,China from 1979 to 1983,the seasonal variations of PHC content and monthly changes of precipitation in Jiaozhou Bay were analyzed. The results showed that seen from the spatial and temporal distribution,the seasonal variation of PHC content in the surface water of Jiaozhou Bay was based on the flow of the rivers as well as human activity,so PHC content in the rivers depended on the flow of the rivers and human activity,and the peaks and valleys of PHC content appeared in various seasons. The seasonal variation of PHC content in the surface water of Jiaozhou Bay depended on its land transfer process. The land transfer process was composed of use of PHC by mankind,deposition of PHC in soil and on the earth's surface,and transportation of PHC to offshore waters of sea by rivers and surface runoff. PHC content depended on mankind during the process from being used to entering soil and on precipitation during the process of being transported from soil to ocean.
基金supported by the Natural Science Research Youth Foundation of Hebei Higher Education of China [QN2016084]the National Natural Science Foundation of China[21878066]
文摘This paper investigates the thermal-coupled effect across the wall and the optimal heat transfer region of the wall for enhancing the energy saving effect of dividing wall column (DWC), and also studies the effects of feed thermal condition (q) and middle component composition of feed (cB) on the heat transfer process, the optimal heat transfer region, and the maximum heat transfer quantity across the wall. The simulation results show that the maximum heat transfer quantity across the wall and the potential for energy saving increase with the increase of q, while with the limitation of temperature difference across the wall, the beneficial heat transfer effect between certain range of stages, which are involved in the optimal heat transfer region, cannot be realized completely for a specific value of q. Besides, compared with q, a changing cB does not change the degree of realizing the beneficial heat transfer effect, but can bring about the variation of liquid split ratio (RL) and vapor split ratio (Rv). Thus, for achieving a maximum energy-saving effect of DWC, different q and cB need to find its own corresponding suitable heat transfer process across the wall.
基金Supported by the Doctoral Degree Construction Library of Guizhou Minzu UniversitySupporting Plan Project for New Century Excellent Talents by Ministry of Education(NCET-12-0659)+5 种基金National Natural Science Foundation of China(31560107)Major Project of Science and Technology of Guizhou Province([2004]6007-01)Guizhou R&D Program for Social Development([2014]3036)Scientific Research Project for Introduction of Talents of Guizhou Minzu University([2014]02)Natural Scientific Research Project of Education Department of Guizhou Province,China(KY[2014]266)Joint Foundation of Science and Technology Department of Guizhou Province,China(LH[2014]7376)
文摘Based on the investigation data of PHC content in Jiaozhou Bay,China during 1980-1981,the vertical distribution of PHC content in the water of Jiaozhou Bay was analyzed.The results showed that from 1980 to 1981,the vertical distribution of PHC content in the water of Jiaozhou Bay depended on the water transfer process of PHC.During the water transfer process of PHC,PHC was input from pollution sources into the surface water of the bay firstly,and then it settled to the bottom.The horizontal distribution trends of PHC content in the surface and bottom water,the changes of PHC content in the surface and bottom water,and the vertical changes of PHC content showed that the settlement of PHC was fast and was consistent with PHC content.PHC accumulated at the bottom after continuous settlement of PHC,which revealed the water transfer process of PHC in Jiaozhou Bay.
文摘The coupled heat and moisture transfer in a freezing process of wood particle material was mathematically modeled in the paper. The models were interactively solved by using the numerical method(the finite element method and the finite difference method). By matching the theoretical calculation to an experiment, the nonlinear problem was analyzed and the variable thermophysical parameters concerned was evaluated. The analysis procedure and the evaluation of the parameters were presented in detail. The result of the study showed that by using the method as described in the paper, it was possible to determine the variable (with respect to temperature, moisture content and freezing state) thermophysical parameters which were unknown or difficult to measure as long as the governing equations for a considered process were available. The method can significantly reduces the experiment efforts for determining thermophysical parameters which arc very complicated to measure. The determined variable of the effective heat conductivity of wood particle material was given in the paper. The error of the numerical calculation was also estimated by the comparison with a matched experiment.
文摘The processes of heat and humidity transfer between air and water are what to be studied mainly in the paper, we put forward some main factors which influence the processes of heat and humidity transfer in the air washer. We come to the conclusion that we can change these main factors to achieve different heat and humidity transfer processes and decide processes of heat and humidity transfer of air and water with the initial temperature of spraying water in the air washer. All these results can make things convenient for the air conditioning management.
基金support of Russian Science Foundation (Project No.23-17-00148)as a part of R&D project (State registry No.121062200075-4).
文摘The article focuses on a theoretical and experimental framework for the quantification of interaction between nonlinear geomechnical and physicochemical processes in high-stress coal-bearing rock mass during mining under high seismic risk due to large-scale blasting and earthquakes,as well as because of structural and temperature effects.The tests were aimed to examine and study comprehensively the piston mechanism of gas exchange and mass transfer processes,revealed recently at the Institute of Mining,SB RAS,as well as to explain the fact that the earthquake-induced low-velocity(quasi-meter range)pendulum waves(velocity to 1 m/s and frequency of 0.5–5 Hz)could stimulate an increase in the gas content in coal mines.In order to perform laboratory investigation at the Institute of Mining SB RAS,special-purpose stand for analyzing gas exchange and mass transfer processes in coal-bearing geomaterials under various thermodynamic conditions(P,V,T)and gas composition was constructed in cooperation with the Institute of Semiconductors Physics SB RAS.Matching of air flow rate with compression pressures allowed to obtain relations showing that air flow rate increases at the uncertain time interval under the increasing of the compression pressure.The same measurements was carried out with another gases such as Hydrogen H_(2),Helium He,methane CH_(4),carbon dioxide CO_(2) and carbon oxide CO.The laboratory tests aimed to detailed investigation of the previously revealed“piston mechanism”of gas exchange and mass transfer processes in the coal specimens and their quantitative description in terms of theory of the pendulum waves were carried in the first time.Consequently,there are some arguments for the testing of the opportunity of quantitative description of the“piston mechanism”related to gas exchange and mass transfer processes in the scale of coal mines.It is relevant when pendulum waves induced by powerful earthquakes and technical blasting reaches the mine.
基金supported by the National Natural Science Foundation of China(No.21477050)the International Scientific and Technological Cooperation in Changzhou(No.CZ20140017)+2 种基金Postgraduate Research Innovation Project of Jiangsu Province(Nos.KYCX20_2561,KYCX20_2598)the Jiangsu Planned Projects for Postdoctoral Research Funds(No.2019K112)the Jiangsu Province subsidizes the recruitment of postdoctoral personnel(No.2019Z143)。
文摘Nonylphenol(NP)residues,as a typical endocrine disrupting chemical(EDC),frequently exist in sewage,surface water,groundwater and even drinking water,which poses a serious threat to human health due to its bioaccumulation.In order to remove NP,a series of MIL-100(Fe)/Zn Fe_(2)O_(4)/flake-like porous carbon nitride(MIL/ZC)was synthesized through in-situ synthesis at room temperature.High performance of ternary MIL/ZC is used to degrade NP under visible light irradiation.The results show that 30MIL/ZC2(20 wt.%Zn Fe_(2)O_(4))ternary composite had the best photocatalytic activity(99.84%)when the dosage was 30 mg.Further mechanism analysis shows that the excellent photocatalytic activity of 30MIL/ZC2could be ascribed to the double charge transfer process between flake-like porous carbon nitride(PCN)and other catalysts in the ternary heterojunction,and the separation of photogenerated electron-hole pairs was more effective.In addition,the 30MIL/ZC2 also showed high stability after five cycles of the photodegradation reaction.Furthermore,the active substance(·O_(2)^(-))was considered to be the main active substance in the NP degradation process.Based on the research results,the possible photocatalytic reaction mechanism of 30MIL/ZC2ternary composite was proposed and discussed in detail.
文摘A numerical model is proposed to analyze mass, momentum, and energy transfer between plasma andparticles in d.c. arc-heated and confined jet reactors at atmospheric pressure. It emphasizes the phasechange and thermal chemistry of particles and includes some other effects such as flow turbulence, gascompressibility and temperature-dependence of the transport properties under the plasma condition.Example calculations for plasma-dissociated zircon process indicate the influences of reactor operationparameters on the plasma jet and particle behavior.
文摘According to heat transfer principle and the process of solving engineering problems by finite element method, examples were given to demonstrate how finite element analysis can be used to describe transient heat transfer through fabrics. Details were given to describe how conduction and convection affect temperature distribution and heat loss during heat transfer processes by taking advantage of the quick calculation of FEA software MSC.Marc. Experimental results show good agreement with the theoretical results.
文摘A 3-D mathematical model considering turbulence phenomena has been established based on a computational fluid dynamics technique, so called 3-D SOLA-VOF (Solution Algorithm-Volume of Fluid), to simulate the fluid flow of mold filling process of die casting. In addition, the mathematical model for simulating the heat transfer in die casting process has also been established. The computation program has been developed by the authors with the finite difference method (FDM) recently. As verification, the mold filling process of a S-shaped die casting has been simulated and the simulation results coincide with that of the benchmark test. Finally, as a practical application, the gating design of a motorcycle component was modified by the mold filling simulation and the dies design of another motorcycle component was optimized by the heat transfer simulation. All the optimized designs were verified by the production practice.
文摘Interfacial charge transfer kinetics of the nanocrystalline CdSe thin film electrodes have been studied in sodium polysulfide solutions by intensity modulated photocurrent spectroscopy (IMPS). The interfacial direct and indirect charge transfer and recombination processes were analyzed in terms of the parameters: normalized steady state photocurrents and surface state lifetimes obtained by measuring the IMPS responses under different applied potentials and different solution concentrations. IMPS responses of polycrystalline CdSe thin film electrodes were also presented for comparison.
基金financially supported by the CAS Knowledge Innovation Key Project (Grant No. KZCX2-YW- 330)the National Science Fund FosteringTalents in Basic Research to Glaciology and Geocryology (Grant No. J0630966)
文摘Gas hydrates formation and dissociation processes inside porous media are always accompanied by water transfer behavior, which is similar to the water behavior of ice freezing and thawing processes. These processes have been studied by many researchers, but all the studies are so far on the water transfer characteristics outside porous media and the water transfer characteristics inside porous media have been little known. In this study, in order to study the water transfer characteristics inside porous media during methane hydrate formation and dissociation processes, a novel apparatus with three pF-meter sensors which can detect water content changes inside porous media was applied. It was experimentally observed that methane hydrate formation processes were accompanied by water transfer from bottom to top inside porous media, however, the water behavior during hydrate dissociation processes was abnormal, for which more studies are needed to find out the real reason in our future work.
基金supported by the National High-Tech Research & Develop-ment Program of China (Grant No. 2007AA04Z348)China Postdoctoral Science Foundation (Grant No. 20080440139)
文摘The electrical resistance-pressure strain sensitivity of carbon nanotube network (NTN)/polymer composite is investigated. In this research, polydimethylsiloxane (PDMS) is used as the polymer matrix. The composite of NTN embedded in PDMS matrix has been fabricated by using filtration and transfer process. The thickness of NTN/PDMS composite can be controlled. Electrical re- sistance and pressure strain of the NTN/PDMS composite are measured simultaneously. Electrical resistance of NTN/PDMS composite has been obtained as a function of pressure strain. The NTN/PDMS composite exhibits linear change in electrical re- sistance as a result of pressure strain and has improved electrical resistance-pressure strain sensitivity. The NTN/PDMS composite has 90.6% resistance change at 6% pressure strain. The electrical resistance-pressure strain sensitivity of NTN/PDMS composite using filtration and transfer process is 2.13 times of the traditional NTN/PDMS composite. The characteristic in electrical resis- tance change implies that NTN/PDMS composite can be used as pressure strain sensors and applied to sensor systems.
基金Supported by the National Key Research and Development Program of China(2018YFB0604903)National Natural Science Foundation of China(21776202,21336007)Major Science and Technology Program for Water Pollution Control and Treatment(2015ZX07202-013)
文摘The concept of process intensification(PI) has absorbed diverse definitions and stays true to the mission—'do more with less', which is an approach purposed by chemical engineers to solve the global energy & environment problems. To date, the focus of PI has been on processes mainly involving vapor/liquid systems. Based on the fundamental principles of vapor–liquid mass transfer process like distillation and absorption, there are three strategies to intensify interphase mass transfer: enhancing the overall driving force, improving the mass transfer coefficient and enlarging the vapor–liquid interfacial area. More specifically, this article herein provides an overview of various technologies to strengthen the vapor–liquid mass transfer, including application of external fields, addition of third substances, micro-chemical technology and usage of solid foam, with the objective to contribute to the future developments and potential applications of PI in scientific research and industrial sectors.
文摘In this work, the in-situ TiC panicles reinforced composite coating was prepared by plasma transferred arc process on the surface of Q235 steel. Microstructures, phase composition and wear property of the coating were investigated. The results showed that the composite coating consisted mainly of T-Ni, TiC, Cr23C6, Cr7C3, Ni3Si, CrB, Cr5B3 and FeNi3 phases, and was characterized by fine TiC panicles embedded in Ni matrix. The wear resistance of composite coating was significantly improved compared with that of the steel substrate. The wear volume loss of the substrate was 443 mm3, which was about 9 times as that of in-situ TiC particles reinforced composite coating (49 mm3 ). It is mainly attributed to the presence of chromium carbide particles and in-situ TiC particles and their favorable combination with Ni matrix.
基金supported by the CAS Knowledge Innovation Key Project (Grant No.KZCX2-YW-330)the National Science Fund Fostering Talents in Basic Research to Glaciology and Geocryology (Grant No.J0630966)
文摘In order to study water transfer characteristics inside non-saturated media during methane hydrate formation and dissociation processes,water changes on the top,middle and bottom locations of experimental media during the reaction processes were continuously followed with a novel apparatus with three pF-meter sensors.Coarse sand,fine sand and loess were chosen as experimental media.It was experimentally observed that methane hydrate was easier formed inside coarse sand and fine sand than inside loess.Methane hydrate formation configuration and water transfer characteristics during methane hydrate formation processes were very different among the different non-saturated media,which were important for understanding methane hydrate formation and dissociation mechanism inside sediments in nature.
文摘Fault diagnosis is an important measure to ensure the safety of production, and all kinds of fault diagnosis methods are of importance in actual production process. However, the complexity and uncertainty of production process often lead to the changes of data distribution and the emergence of new fault classes, and the number of the new fault classes is unpredictable. The reconstruction of the fault diagnosis model and the identification of new fault classes have become core issues under the circumstances. This paper presents a fault diagnosis method based on model transfer learning and the main contributions of the paper are as follows: 1) An incremental model transfer fault diagnosis method is proposed to reconstruct the new process diagnosis model. 2) Breaking the limit of existing method that the new process can only have one more class of faults than the old process, this method can identify M faults more in the new process with the thought of incremental learning. 3) The method offers a solution to a series of problems caused by the increase of fault classes. Experiments based on Tennessee-Eastman process and ore grinding classification process demonstrate the effectiveness and the feasibility of the method.