To assess whether a development strategy will be profitable enough,production forecasting is a crucial and difficult step in the process.The development history of other reservoirs in the same class tends to be studie...To assess whether a development strategy will be profitable enough,production forecasting is a crucial and difficult step in the process.The development history of other reservoirs in the same class tends to be studied to make predictions accurate.However,the permeability field,well patterns,and development regime must all be similar for two reservoirs to be considered in the same class.This results in very few available experiences from other reservoirs even though there is a lot of historical information on numerous reservoirs because it is difficult to find such similar reservoirs.This paper proposes a learn-to-learn method,which can better utilize a vast amount of historical data from various reservoirs.Intuitively,the proposed method first learns how to learn samples before directly learning rules in samples.Technically,by utilizing gradients from networks with independent parameters and copied structure in each class of reservoirs,the proposed network obtains the optimal shared initial parameters which are regarded as transferable information across different classes.Based on that,the network is able to predict future production indices for the target reservoir by only training with very limited samples collected from reservoirs in the same class.Two cases further demonstrate its superiority in accuracy to other widely-used network methods.展开更多
The development of novel single-atom catalysts with optimal electron configuration and economical noble-metal cocatalyst for efficient photocatalytic hydrogen production is of great importance,but still challenging.He...The development of novel single-atom catalysts with optimal electron configuration and economical noble-metal cocatalyst for efficient photocatalytic hydrogen production is of great importance,but still challenging.Herein,we fabricate Pt and Co single-atom sites successively on polymeric carbon nitride(CN).In this Pt_(1)-Co_(1)/CN bimetallic single-atom catalyst,the noble-metal active sites are maximized,and the single-atomic Co_(1)N_4sites are tuned to Co_(1)N_3sites by photogenerated electrons arising from the introduced single-atomic Pt_(1)N_4sites.Mechanism studies and density functional theory(DFT)calculations reveal that the 3d orbitals of Co_(1)N_3single sites are filled with unpaired d-electrons,which lead to the improved visible-light response,carrier separation and charge migration for CN photocatalysts.Thereafter,the protons adsorption and activation are promoted.Taking this advantage of long-range electron synergy in bimetallic single atomic sites,the photocatalytic hydrogen evolution activity over Pt_(1)-Co_(1)/CN achieves 915.8 mmol g^(-1)Pt h^(-1),which is 19.8 times higher than Co_(1)/CN and 3.5 times higher to Pt_(1)/CN.While this electron-synergistic effect is not so efficient for Pt nanoclusters.These results demonstrate the synergistic effect at electron-level and provide electron-level guidance for the design of efficient photocatalysts.展开更多
The lack of effective charge transfer driving force and channel limits the electron directional migration in nanoclusters(NC)-based heterostructures,resulting in poor photocatalytic performance.Herein,a Z-scheme NC-ba...The lack of effective charge transfer driving force and channel limits the electron directional migration in nanoclusters(NC)-based heterostructures,resulting in poor photocatalytic performance.Herein,a Z-scheme NC-based heterojunction(Pt1Ag28-BTT/CoP,BTT=1,3,5-benzenetrithiol)with strong internal electric field is constructed via interfacial Co-S bond,which exhibits an absolutely superiority in photocatalytic performance with 24.89 mmol·h^(−1)·g−1 H_(2)production rate,25.77%apparent quantum yield at 420 nm,and~100%activity retention in stability,compared with Pt1Ag28-BDT/CoP(BDT=1,3-benzenedithiol),Ag29-BDT/CoP,and CoP.The enhanced catalytic performance is contributed by the dual modulation strategy of inner core and outer shell of NC,wherein,the center Pt single atom doping regulates the band structure of NC to match well with CoP,builds internal electric field,and then drives photogenerated electrons steering;the accurate surface S modification promotes the formation of Co-S atomic-precise interface channel for further high-efficient Z-scheme charge directional migration.This work opens a new avenue for designing NC-based heterojunction with matchable band structure and valid interfacial charge transfer.展开更多
Rapid industrialization has accordingly increased the demand for energy.This has resulted in the increasingly severe energy and environmental crises.Hydrogen production,based on the photocatalytic water splitting driv...Rapid industrialization has accordingly increased the demand for energy.This has resulted in the increasingly severe energy and environmental crises.Hydrogen production,based on the photocatalytic water splitting driven by sunlight,is able to directly convert solar energy into a usable or storable energy resource,which is considered to be an ideal alternative energy source to assist in solving the energy crisis and environmental pollution.Unfortunately,the hydrogen production efficiency of single phase photocatalysts is too low to meet the practical requirements.The construction of heterostructured photocatalyst systems,which are comprised of multiple components or multiple phases,is an efficient method to facilitate the separation of electron‐hole pairs to minimize the energy‐waste,provide more electrons,enhance their redox ability,and hence improve the photocatalytic activity.We summarize the recent progress in the rational design and fabrication of nanoheterostructured photocatalysts.The heterojunction photocatalytic hydrogen generation systems can be divided into type‐I,type‐II,pn‐junction and Z‐scheme junction,according to the differences in the transfer of the photogenerated electrons and holes.Finally,a summary and some of the challenges and prospects for the future development of heterojunction photocatalytic systems are discussed.展开更多
Exploring low-cost cocatalyst to take over noble metal cocatalyst is still challenging in the field of photocatalytic proton reduction.Herein,Ni-P alloy clusters are anchored onto the surface of polymeric carbon nitri...Exploring low-cost cocatalyst to take over noble metal cocatalyst is still challenging in the field of photocatalytic proton reduction.Herein,Ni-P alloy clusters are anchored onto the surface of polymeric carbon nitride through a chemical plating method and serve as highly efficient and stable cocatalyst toward photocatalytic proton reduction.An effective role in promoting the charge separation and migration of the photocatalytic system is demonstrated for Ni-P clusters,which essentially enhance the photocatalytic H2-production rate to a value of 1506μmol h^–1 g^–1.This performance is comparable to that of the benchmark of Pt-modified carbon nitride.This work highlights that the Ni-P alloy could be a potential alternative to noble metal cocatalyst in the photocatalytic reactions.展开更多
Background:In vitro embryo production(IVP)and embryo transfer(ET)are two very common assisted reproductive technologies(ART)in human and cattle.However,in pig,the combination of either procedures,or even their use sep...Background:In vitro embryo production(IVP)and embryo transfer(ET)are two very common assisted reproductive technologies(ART)in human and cattle.However,in pig,the combination of either procedures,or even their use separately,is still considered suboptimal due to the low efficiency of IVP plus the difficulty of performing ET in the long and contorted uterus of the sow.In addition,the potential impact of these two ART on the health of the offspring is unknown.We investigated here if the use of a modified IVP system,with natural reproductive fluids(RF)as supplements to the culture media,combined with a minimally invasive surgery to perform ET,affects the output of the own IVP system as well as the reproductive performance of the mother and placental molecular traits.Results:The blastocyst rates obtained by both in vitro systems,conventional(C-IVP)and modified(RF-IVP),were similar.Pregnancy and farrowing rates were also similar.However,when compared to in vivo control(artificial insemination,AI),litter sizes of both IVP groups were lower,while placental efficiency was higher in AI than in RF-IVP.Gene expression studies revealed aberrant expression levels for PEG3 and LUM in placental tissue for C-IVP group when compared to AI,but not for RF-IVP group.Conclusions:The use of reproductive fluids as additives for the culture media in pig IVP does not improve reproductive performance of recipient mothers but could mitigate the impact of artificial procedures in the offspring.展开更多
An innovative in-flight glass melting technology with induced thermal plasmas was developed for the purpose of energy conservation and environmental protection. Two-dimensional modeling was used to simulate the thermo...An innovative in-flight glass melting technology with induced thermal plasmas was developed for the purpose of energy conservation and environmental protection. Two-dimensional modeling was used to simulate the thermofluid fields in the plasma torch. The in-flight melting behavior of glass raw material was investigated by various analysis methods. Results showed that the plasma temperature was up to 10000 K with a maximum velocity over 30 m/s, which made it possible to melt the granulated glass raw material within milliseconds. The carbonates in the raw material decomposed completely and the compounds in the raw material attainted 100% vitrification during the in-flight time from the nozzle exit to substrate. The particle melting process is similar to the unreacted-core shrinking model.展开更多
Frost can cause serious economic losses in cranberry fields, particularly in northern regions. When the air temperature reaches a low critical threshold, sprinklers are operated to protect vines, to insure crop produc...Frost can cause serious economic losses in cranberry fields, particularly in northern regions. When the air temperature reaches a low critical threshold, sprinklers are operated to protect vines, to insure crop production and profitability. To avoid frost injury, proper positioning of temperature sensors is critical. A field experiment was designed and conducted to determine the optimal installation height of sensors above soil surface. Temperature data was used to investigate the spatial temperature gradient in the section of a cranberry field. A computer simulation of the temperature profile was performed to simulate the effect of wind velocity on the prediction of air temperature. For optimal use, sensors should be installed at the height of the canopy and several meters away from a dike. On nights with low wind velocities, the canopy air temperature was 2.7°C below that of 500 cm above the ground. The sensors should be put at least five m away from a dike to avoid the transfer of heat from the dike to the sensor. Also, multiple sensors should be installed because of the large variations in air temperature that were measured across the experiment. The simulated temperature indicated that wind velocity strongly influenced the temperature estimation;the effect of the wind on temperatures gradients was greater when the wind velocity was low (<2.3 m/s).展开更多
With the development of internet technology, customers play more and more important roles in new product development. The paper defines customer knowledge; then analyses the modes of customer knowledge transferring ba...With the development of internet technology, customers play more and more important roles in new product development. The paper defines customer knowledge; then analyses the modes of customer knowledge transferring based on SECI model and information emission model. Finally customer knowledge transferring mechanism is discussed.展开更多
Knowledge-based transfer learning techniques have shown good performance for brain tumor classification,especially with small datasets.However,to obtain an optimized model for targeted brain tumor classification,it is...Knowledge-based transfer learning techniques have shown good performance for brain tumor classification,especially with small datasets.However,to obtain an optimized model for targeted brain tumor classification,it is challenging to select a pre-trained deep learning(DL)model,optimal values of hyperparameters,and optimization algorithm(solver).This paper first presents a brief review of recent literature related to brain tumor classification.Secondly,a robust framework for implementing the transfer learning technique is proposed.In the proposed framework,a Cartesian product matrix is generated to determine the optimal values of the two important hyperparameters:batch size and learning rate.An extensive exercise consisting of 435 simulations for 11 state-of-the-art pre-trained DL models was performed using 16 paired hyperparameters from the Cartesian product matrix to input the model with the three most popular solvers(stochastic gradient descent with momentum(SGDM),adaptive moment estimation(ADAM),and root mean squared propagation(RMSProp)).The 16 pairs were formed using individual hyperparameter values taken from literature,which generally addressed only one hyperparameter for optimization,rather than making a grid for a particular range.The proposed framework was assessed using a multi-class publicly available dataset consisting of glioma,meningioma,and pituitary tumors.Performance assessment shows that ResNet18 outperforms all other models in terms of accuracy,precision,specificity,and recall(sensitivity).The results are also compared with existing state-of-the-art research work that used the same dataset.The comparison was mainly based on performance metric“accuracy”with support of three other parameters“precision,”“recall,”and“specificity.”The comparison shows that the transfer learning technique,implemented through our proposed framework for brain tumor classification,outperformed all existing approaches.To the best of our knowledge,the proposed framework is an efficient framework that helped reduce the computational complexity and the time to attain optimal values of two important hyperparameters and consequently the optimized model with an accuracy of 99.56%.展开更多
In this paper, lab scale production carried out of calcium carbonate in 400 mL open cylindrical beaker reactor following fuzzy logic approach is reported. 10 grams of Calcium hydroxide is mixed in 250 mL deionized wat...In this paper, lab scale production carried out of calcium carbonate in 400 mL open cylindrical beaker reactor following fuzzy logic approach is reported. 10 grams of Calcium hydroxide is mixed in 250 mL deionized water. Continuous jet supply of carbon dioxide is maintained at controlled flow rate. Reaction histories are noted for different reaction temperatures. Continuous constant magnetic stirring is applied to maintain homogeneity. The data obtained is fuzzified by constructing universe of discourse of temperature, reaction time, and amounts of reactants with reaction conversion. Rule based model is tabulated and results show that fuzzy logic approach is promising to set on data to plan and scale up the process. It is also found that a jump can not be made at this time with few studies of fuzzy logic applications to physiochemical processes unless otherwise amassing and storing up plentiful deduced explorations.展开更多
Global warming that triggered the climate change is largely due to increased CO2 concentrations. Utilization of Chlorella sp. to reduce CO2 gas is a promising potential. Chlorella can efficiently reduce CO2 and easily...Global warming that triggered the climate change is largely due to increased CO2 concentrations. Utilization of Chlorella sp. to reduce CO2 gas is a promising potential. Chlorella can efficiently reduce CO2 and easily be adapted into the photobioreactor system engineering. In this research, the type of microalgae which is used is Chlorella vulgaris in Benneck medium. The system of used reactor is mid-scale bubble column photobioreactor flowed by air which contains 5% CO2. Chlorella vulgaris biomass production will be increased by adjusting the cell density in the photobioreactor. These arrangements will be implemented through a continuous treatment of cell entrapment. The arrangement of cell density in continuous reactor has been proven to increase production of Chlorella vulgaris biomass about 1.25 times more than cultivation without arrangement of cell density by using the same number of inoculums. The results also have shown that the average rate of CO2 fixation and Carbon Transfer Rate (CTR) are obtained at cell entrapment condition about 17 times larger. Continuous cellular entrapment method is very potential to be developed as a method for the production of biomass. Lipids and carotene that have been produced from Ch. vulgaris respectively are 18.24% and 9.42 ppm.展开更多
Conventional chemical oxidation of aldehydes such as furfural to corresponding acids by molecular oxygen usually needs high pressure to increase the solubility of oxygen in aqueous phase,while electrochemical oxidatio...Conventional chemical oxidation of aldehydes such as furfural to corresponding acids by molecular oxygen usually needs high pressure to increase the solubility of oxygen in aqueous phase,while electrochemical oxidation needs input of external electric energy.Herein,we developed a liquid flow fuel cell(LFFC)system to achieve oxidation of furfural in anode for furoic acid production with co-production of hydrogen gas.By controlling the electron transfer in cathode for reduction of oxygen,efficient generation of electricity or production of H_(2)O_(2)were achieved.Metal oxides especially Ag_(2)O have been screened as the efficient catalyst to promote the oxidation of aldehydes,while liquid redox couples were used for promoting the kinetics of oxygen reduction.A novel alkaline-acidic asymmetric design was also used for anolyte and catholyte,respectively,to promote the efficiency of electron transfer.Such an LFFC system achieves efficient conversion of chemical energy of aldehyde oxidation to electric energy and makes full use the transferred electrons for high-value added products without input of external energy.With(VO_(2))_(2)SO_(4)as the electron carrier in catholyte for four-electron reduction of oxygen,the peak output power density(Pmax)at room temperature reached 261 mW/cm^(2)with furoic acid and H_(2)yields of 90%and 0.10 mol/mol furfural,respectively.With anthraquinone-2-sulfonate(AQS)as the cathodic electron carrier,Pmaxof 60 mW/cm^(2)and furoic acid,H_(2)and H_(2)O_(2)yields of 0.88,0.15 and 0.41 mol/mol furfural were achieved,respectively.A new reaction mechanism on furfural oxidation on Ag_(2)O anode was proposed,referring to one-electron and two-electron reaction pathways depending on the fate of adsorbed hydrogen atom transferred from furfural aldehyde group.展开更多
The orderly transfer of the manufacturing industry is a major action in China’s industrial restructuring.From the perspective of industrial transfer,we used the concentration ratio to depict the trend of the industri...The orderly transfer of the manufacturing industry is a major action in China’s industrial restructuring.From the perspective of industrial transfer,we used the concentration ratio to depict the trend of the industrial transfer of energy-intensive manufacturing in the eastern,central,and western regions since the policy of large-scale development of western China was implemented.We measured the total factor productivity(TFP)of western China using the DEAMalmquist index method.We conducted a regression analysis to measure the effect of western China’s undertaking of the transfer of the energy-intensive manufacturing industry.The findings of this study show that during 2000–2019,eleven provinces(as well as autonomous regions and municipalities)in western China undertook the transfer of the energy-intensive manufacturing industry from the eastern and central regions to varying degrees,exhibiting significant phase features regarding the rate and scale of transfers.Further investigation also demonstrated that the transfer of energy-intensive manufacturing industries has a U-shaped enabling effect on TFP in western China with the scale effect greater than the technology effect.Therefore,it is necessary to transition from“extensive industrial transfer”at the cost of the labor force,land,and resources to“modern industrial transfer”featured by technology and efficiency improvements to contribute to industrial restructuring in western China effectively.展开更多
基金This work is supported by the National Natural Science Foundation of China under Grant 52274057,52074340 and 51874335the Major Scientific and Technological Projects of CNPC under Grant ZD2019-183-008+2 种基金the Major Scientific and Technological Projects of CNOOC under Grant CCL2022RCPS0397RSNthe Science and Technology Support Plan for Youth Innovation of University in Shandong Province under Grant 2019KJH002111 Project under Grant B08028.
文摘To assess whether a development strategy will be profitable enough,production forecasting is a crucial and difficult step in the process.The development history of other reservoirs in the same class tends to be studied to make predictions accurate.However,the permeability field,well patterns,and development regime must all be similar for two reservoirs to be considered in the same class.This results in very few available experiences from other reservoirs even though there is a lot of historical information on numerous reservoirs because it is difficult to find such similar reservoirs.This paper proposes a learn-to-learn method,which can better utilize a vast amount of historical data from various reservoirs.Intuitively,the proposed method first learns how to learn samples before directly learning rules in samples.Technically,by utilizing gradients from networks with independent parameters and copied structure in each class of reservoirs,the proposed network obtains the optimal shared initial parameters which are regarded as transferable information across different classes.Based on that,the network is able to predict future production indices for the target reservoir by only training with very limited samples collected from reservoirs in the same class.Two cases further demonstrate its superiority in accuracy to other widely-used network methods.
基金the support of the National Natural Science Foundation of China (22002118,22208262,52271228,52202298,52201279,51834009,51801151)the Natural Science Foundation of Shaanxi Province (2021JQ-468,2020JZ-47)+2 种基金the Natural Science Foundation of Shaanxi Provincial Department of Education (21JP086)the Postdoctoral Research Foundation of China (2020 M683528,2020TQ0245,2018M633643XB)the Hundred Talent Program of Shaanxi Province。
文摘The development of novel single-atom catalysts with optimal electron configuration and economical noble-metal cocatalyst for efficient photocatalytic hydrogen production is of great importance,but still challenging.Herein,we fabricate Pt and Co single-atom sites successively on polymeric carbon nitride(CN).In this Pt_(1)-Co_(1)/CN bimetallic single-atom catalyst,the noble-metal active sites are maximized,and the single-atomic Co_(1)N_4sites are tuned to Co_(1)N_3sites by photogenerated electrons arising from the introduced single-atomic Pt_(1)N_4sites.Mechanism studies and density functional theory(DFT)calculations reveal that the 3d orbitals of Co_(1)N_3single sites are filled with unpaired d-electrons,which lead to the improved visible-light response,carrier separation and charge migration for CN photocatalysts.Thereafter,the protons adsorption and activation are promoted.Taking this advantage of long-range electron synergy in bimetallic single atomic sites,the photocatalytic hydrogen evolution activity over Pt_(1)-Co_(1)/CN achieves 915.8 mmol g^(-1)Pt h^(-1),which is 19.8 times higher than Co_(1)/CN and 3.5 times higher to Pt_(1)/CN.While this electron-synergistic effect is not so efficient for Pt nanoclusters.These results demonstrate the synergistic effect at electron-level and provide electron-level guidance for the design of efficient photocatalysts.
基金the Natural Science research project of Universities in Anhui Province(No.KJ2021ZD0001)the Natural Science Foundation of Anhui Province(No.2208085MB20)the National Natural Science Foundation of China(No.22101001).
文摘The lack of effective charge transfer driving force and channel limits the electron directional migration in nanoclusters(NC)-based heterostructures,resulting in poor photocatalytic performance.Herein,a Z-scheme NC-based heterojunction(Pt1Ag28-BTT/CoP,BTT=1,3,5-benzenetrithiol)with strong internal electric field is constructed via interfacial Co-S bond,which exhibits an absolutely superiority in photocatalytic performance with 24.89 mmol·h^(−1)·g−1 H_(2)production rate,25.77%apparent quantum yield at 420 nm,and~100%activity retention in stability,compared with Pt1Ag28-BDT/CoP(BDT=1,3-benzenedithiol),Ag29-BDT/CoP,and CoP.The enhanced catalytic performance is contributed by the dual modulation strategy of inner core and outer shell of NC,wherein,the center Pt single atom doping regulates the band structure of NC to match well with CoP,builds internal electric field,and then drives photogenerated electrons steering;the accurate surface S modification promotes the formation of Co-S atomic-precise interface channel for further high-efficient Z-scheme charge directional migration.This work opens a new avenue for designing NC-based heterojunction with matchable band structure and valid interfacial charge transfer.
基金supported by the National Natural Science Foundation of China (51572253,21271165)Scientific Research Grant of Hefei Science Center of CAS (2015SRG-HSC048)Cooperation between NSFC and Netherlands Organization for Scientific Research (51561135011)~~
文摘Rapid industrialization has accordingly increased the demand for energy.This has resulted in the increasingly severe energy and environmental crises.Hydrogen production,based on the photocatalytic water splitting driven by sunlight,is able to directly convert solar energy into a usable or storable energy resource,which is considered to be an ideal alternative energy source to assist in solving the energy crisis and environmental pollution.Unfortunately,the hydrogen production efficiency of single phase photocatalysts is too low to meet the practical requirements.The construction of heterostructured photocatalyst systems,which are comprised of multiple components or multiple phases,is an efficient method to facilitate the separation of electron‐hole pairs to minimize the energy‐waste,provide more electrons,enhance their redox ability,and hence improve the photocatalytic activity.We summarize the recent progress in the rational design and fabrication of nanoheterostructured photocatalysts.The heterojunction photocatalytic hydrogen generation systems can be divided into type‐I,type‐II,pn‐junction and Z‐scheme junction,according to the differences in the transfer of the photogenerated electrons and holes.Finally,a summary and some of the challenges and prospects for the future development of heterojunction photocatalytic systems are discussed.
基金supported by the National Natural Science Foundation of China(21773179,U1705251 and 21433007)the Natural Science Foundation of Hubei Province of China(2017CFA031)the Excellent Dissertation Cultivation Funds of Wuhan University of Technology(2016-YS-001)~~
文摘Exploring low-cost cocatalyst to take over noble metal cocatalyst is still challenging in the field of photocatalytic proton reduction.Herein,Ni-P alloy clusters are anchored onto the surface of polymeric carbon nitride through a chemical plating method and serve as highly efficient and stable cocatalyst toward photocatalytic proton reduction.An effective role in promoting the charge separation and migration of the photocatalytic system is demonstrated for Ni-P clusters,which essentially enhance the photocatalytic H2-production rate to a value of 1506μmol h^–1 g^–1.This performance is comparable to that of the benchmark of Pt-modified carbon nitride.This work highlights that the Ni-P alloy could be a potential alternative to noble metal cocatalyst in the photocatalytic reactions.
基金This study was funded by Spanish Ministry of Economy and Competitiveness(MINECO)and European Regional Development Fund(FEDER)grant AGL2015–66341-R and Fundación Seneca,Agencia de Ciencia y Tecnología de la Region de Murcia grant 20040/GERM/16.EPO received funding from“Ayudas para estancias en el extranjero de jóvenes investigadores y estudiantes de doctorado en las líneas de actuación de Campus Mare Nostrum”,R-47/2018,to a doctoral stay at the Babraham Institute(Cambridge,U.K.).
文摘Background:In vitro embryo production(IVP)and embryo transfer(ET)are two very common assisted reproductive technologies(ART)in human and cattle.However,in pig,the combination of either procedures,or even their use separately,is still considered suboptimal due to the low efficiency of IVP plus the difficulty of performing ET in the long and contorted uterus of the sow.In addition,the potential impact of these two ART on the health of the offspring is unknown.We investigated here if the use of a modified IVP system,with natural reproductive fluids(RF)as supplements to the culture media,combined with a minimally invasive surgery to perform ET,affects the output of the own IVP system as well as the reproductive performance of the mother and placental molecular traits.Results:The blastocyst rates obtained by both in vitro systems,conventional(C-IVP)and modified(RF-IVP),were similar.Pregnancy and farrowing rates were also similar.However,when compared to in vivo control(artificial insemination,AI),litter sizes of both IVP groups were lower,while placental efficiency was higher in AI than in RF-IVP.Gene expression studies revealed aberrant expression levels for PEG3 and LUM in placental tissue for C-IVP group when compared to AI,but not for RF-IVP group.Conclusions:The use of reproductive fluids as additives for the culture media in pig IVP does not improve reproductive performance of recipient mothers but could mitigate the impact of artificial procedures in the offspring.
基金the New Energy and Industrial Technology Development Organization of Japan(No.A0006)
文摘An innovative in-flight glass melting technology with induced thermal plasmas was developed for the purpose of energy conservation and environmental protection. Two-dimensional modeling was used to simulate the thermofluid fields in the plasma torch. The in-flight melting behavior of glass raw material was investigated by various analysis methods. Results showed that the plasma temperature was up to 10000 K with a maximum velocity over 30 m/s, which made it possible to melt the granulated glass raw material within milliseconds. The carbonates in the raw material decomposed completely and the compounds in the raw material attainted 100% vitrification during the in-flight time from the nozzle exit to substrate. The particle melting process is similar to the unreacted-core shrinking model.
文摘Frost can cause serious economic losses in cranberry fields, particularly in northern regions. When the air temperature reaches a low critical threshold, sprinklers are operated to protect vines, to insure crop production and profitability. To avoid frost injury, proper positioning of temperature sensors is critical. A field experiment was designed and conducted to determine the optimal installation height of sensors above soil surface. Temperature data was used to investigate the spatial temperature gradient in the section of a cranberry field. A computer simulation of the temperature profile was performed to simulate the effect of wind velocity on the prediction of air temperature. For optimal use, sensors should be installed at the height of the canopy and several meters away from a dike. On nights with low wind velocities, the canopy air temperature was 2.7°C below that of 500 cm above the ground. The sensors should be put at least five m away from a dike to avoid the transfer of heat from the dike to the sensor. Also, multiple sensors should be installed because of the large variations in air temperature that were measured across the experiment. The simulated temperature indicated that wind velocity strongly influenced the temperature estimation;the effect of the wind on temperatures gradients was greater when the wind velocity was low (<2.3 m/s).
文摘With the development of internet technology, customers play more and more important roles in new product development. The paper defines customer knowledge; then analyses the modes of customer knowledge transferring based on SECI model and information emission model. Finally customer knowledge transferring mechanism is discussed.
文摘Knowledge-based transfer learning techniques have shown good performance for brain tumor classification,especially with small datasets.However,to obtain an optimized model for targeted brain tumor classification,it is challenging to select a pre-trained deep learning(DL)model,optimal values of hyperparameters,and optimization algorithm(solver).This paper first presents a brief review of recent literature related to brain tumor classification.Secondly,a robust framework for implementing the transfer learning technique is proposed.In the proposed framework,a Cartesian product matrix is generated to determine the optimal values of the two important hyperparameters:batch size and learning rate.An extensive exercise consisting of 435 simulations for 11 state-of-the-art pre-trained DL models was performed using 16 paired hyperparameters from the Cartesian product matrix to input the model with the three most popular solvers(stochastic gradient descent with momentum(SGDM),adaptive moment estimation(ADAM),and root mean squared propagation(RMSProp)).The 16 pairs were formed using individual hyperparameter values taken from literature,which generally addressed only one hyperparameter for optimization,rather than making a grid for a particular range.The proposed framework was assessed using a multi-class publicly available dataset consisting of glioma,meningioma,and pituitary tumors.Performance assessment shows that ResNet18 outperforms all other models in terms of accuracy,precision,specificity,and recall(sensitivity).The results are also compared with existing state-of-the-art research work that used the same dataset.The comparison was mainly based on performance metric“accuracy”with support of three other parameters“precision,”“recall,”and“specificity.”The comparison shows that the transfer learning technique,implemented through our proposed framework for brain tumor classification,outperformed all existing approaches.To the best of our knowledge,the proposed framework is an efficient framework that helped reduce the computational complexity and the time to attain optimal values of two important hyperparameters and consequently the optimized model with an accuracy of 99.56%.
文摘In this paper, lab scale production carried out of calcium carbonate in 400 mL open cylindrical beaker reactor following fuzzy logic approach is reported. 10 grams of Calcium hydroxide is mixed in 250 mL deionized water. Continuous jet supply of carbon dioxide is maintained at controlled flow rate. Reaction histories are noted for different reaction temperatures. Continuous constant magnetic stirring is applied to maintain homogeneity. The data obtained is fuzzified by constructing universe of discourse of temperature, reaction time, and amounts of reactants with reaction conversion. Rule based model is tabulated and results show that fuzzy logic approach is promising to set on data to plan and scale up the process. It is also found that a jump can not be made at this time with few studies of fuzzy logic applications to physiochemical processes unless otherwise amassing and storing up plentiful deduced explorations.
文摘Global warming that triggered the climate change is largely due to increased CO2 concentrations. Utilization of Chlorella sp. to reduce CO2 gas is a promising potential. Chlorella can efficiently reduce CO2 and easily be adapted into the photobioreactor system engineering. In this research, the type of microalgae which is used is Chlorella vulgaris in Benneck medium. The system of used reactor is mid-scale bubble column photobioreactor flowed by air which contains 5% CO2. Chlorella vulgaris biomass production will be increased by adjusting the cell density in the photobioreactor. These arrangements will be implemented through a continuous treatment of cell entrapment. The arrangement of cell density in continuous reactor has been proven to increase production of Chlorella vulgaris biomass about 1.25 times more than cultivation without arrangement of cell density by using the same number of inoculums. The results also have shown that the average rate of CO2 fixation and Carbon Transfer Rate (CTR) are obtained at cell entrapment condition about 17 times larger. Continuous cellular entrapment method is very potential to be developed as a method for the production of biomass. Lipids and carotene that have been produced from Ch. vulgaris respectively are 18.24% and 9.42 ppm.
基金supported by the National Natural Science Foundation of China(No.2187817622178197)。
文摘Conventional chemical oxidation of aldehydes such as furfural to corresponding acids by molecular oxygen usually needs high pressure to increase the solubility of oxygen in aqueous phase,while electrochemical oxidation needs input of external electric energy.Herein,we developed a liquid flow fuel cell(LFFC)system to achieve oxidation of furfural in anode for furoic acid production with co-production of hydrogen gas.By controlling the electron transfer in cathode for reduction of oxygen,efficient generation of electricity or production of H_(2)O_(2)were achieved.Metal oxides especially Ag_(2)O have been screened as the efficient catalyst to promote the oxidation of aldehydes,while liquid redox couples were used for promoting the kinetics of oxygen reduction.A novel alkaline-acidic asymmetric design was also used for anolyte and catholyte,respectively,to promote the efficiency of electron transfer.Such an LFFC system achieves efficient conversion of chemical energy of aldehyde oxidation to electric energy and makes full use the transferred electrons for high-value added products without input of external energy.With(VO_(2))_(2)SO_(4)as the electron carrier in catholyte for four-electron reduction of oxygen,the peak output power density(Pmax)at room temperature reached 261 mW/cm^(2)with furoic acid and H_(2)yields of 90%and 0.10 mol/mol furfural,respectively.With anthraquinone-2-sulfonate(AQS)as the cathodic electron carrier,Pmaxof 60 mW/cm^(2)and furoic acid,H_(2)and H_(2)O_(2)yields of 0.88,0.15 and 0.41 mol/mol furfural were achieved,respectively.A new reaction mechanism on furfural oxidation on Ag_(2)O anode was proposed,referring to one-electron and two-electron reaction pathways depending on the fate of adsorbed hydrogen atom transferred from furfural aldehyde group.
文摘The orderly transfer of the manufacturing industry is a major action in China’s industrial restructuring.From the perspective of industrial transfer,we used the concentration ratio to depict the trend of the industrial transfer of energy-intensive manufacturing in the eastern,central,and western regions since the policy of large-scale development of western China was implemented.We measured the total factor productivity(TFP)of western China using the DEAMalmquist index method.We conducted a regression analysis to measure the effect of western China’s undertaking of the transfer of the energy-intensive manufacturing industry.The findings of this study show that during 2000–2019,eleven provinces(as well as autonomous regions and municipalities)in western China undertook the transfer of the energy-intensive manufacturing industry from the eastern and central regions to varying degrees,exhibiting significant phase features regarding the rate and scale of transfers.Further investigation also demonstrated that the transfer of energy-intensive manufacturing industries has a U-shaped enabling effect on TFP in western China with the scale effect greater than the technology effect.Therefore,it is necessary to transition from“extensive industrial transfer”at the cost of the labor force,land,and resources to“modern industrial transfer”featured by technology and efficiency improvements to contribute to industrial restructuring in western China effectively.