“Five education”is pivotal for students’all-round development.However,primary English teaching currently faces challenges including the superficial implementation of“Five education”.This study employed action res...“Five education”is pivotal for students’all-round development.However,primary English teaching currently faces challenges including the superficial implementation of“Five education”.This study employed action research to explore practical methods for integrating English picture book with textbook to implement“Five education”.Through two rounds of iterative action research,a three-stage activity-based teaching path was developed and refined,enabling the progressive infusion of“Five education”objectives across the learning cycle.Findings demonstrated that this integrated approach-particularly when supported by strategies such as picture book background videos and audio-edited narrative connections-effectively deepened the implementation of“Five education”,mitigated student reading fatigue,and significantly improved students’reading fluency and labor initiative,thus provided a replicable practical paradigm for realizing“Five education simultaneously”.展开更多
The effects of leaching temperature(60−105°C),NH4Cl concentration(3−7 mol/L),liquid/solid ratio(4:1−12:1 mL/g),stirring speed(150−750 r/min),and leaching time(5−90 min)on the leaching rates of Zn and Pb were inve...The effects of leaching temperature(60−105°C),NH4Cl concentration(3−7 mol/L),liquid/solid ratio(4:1−12:1 mL/g),stirring speed(150−750 r/min),and leaching time(5−90 min)on the leaching rates of Zn and Pb were investigated.The leaching kinetics of Zn-and Pb-rich fuming dust with a NH4Cl solution was also studied.The leaching rates of Zn and Pb respectively reached 98.2%and 75.6%at leaching temperature of 100°C,an NH4Cl concentration of 7.0 mol/L,a liquid/solid ratio of 10:1 mL/g,a stirring speed of 450 r/min and leaching time of 60 min.The kinetics results indicate that the leaching of Zn and Pb conforms to the shrinking unreacted core model and is controlled by the internal diffusion of NH4Cl through the reacted fuming dust layer and external diffusion of NH4Cl through the leaching solution boundary layer,respectively.The apparent activation energies of Zn and Pb are 23.922 and 19.139 kJ/mol,respectively.This study demonstrates that the use of NH4Cl solution,without ammonia,is an environmentally friendly method for simultaneous extracting Zn and Pb from the fuming dust of lead blast furnace slag.展开更多
Correction to:Rare Met.https://doi.org/10.1007/s12598-019-01312-4 In the original publication,in Figure 3,part d has been mistakenly published same as part c.The correct version of Fig.3 is given in this Correction.
Rice is one of the most important staple food for over half of the world＇s population,and a substantial increase in productivity and quality of rice grain will be required to feed a growing human population.Grain siz...Rice is one of the most important staple food for over half of the world＇s population,and a substantial increase in productivity and quality of rice grain will be required to feed a growing human population.Grain size and shape are the two important components contributing to grain yield and quality,because they impact both yield potential and end-use quality.展开更多
Up to present,the problem of the evaluation of fault diagnosability for nonlinear systems has been investigated by many researchers.However,no attempt has been done to evaluate the diagnosability of multiple faults oc...Up to present,the problem of the evaluation of fault diagnosability for nonlinear systems has been investigated by many researchers.However,no attempt has been done to evaluate the diagnosability of multiple faults occurring simultaneously for nonlinear systems.This paper proposes a method based on differential geometry theories to solve this problem.Then the evaluation of fault diagnosability for affine nonlinear systems with multiple faults occurring simultaneously is achieved.To deal with the effect of control laws on the evaluation results of fault diagnosability,a design scheme of the evaluation of fault diagnosability is proposed.Then the influence of uncertainties on the evaluation results of fault diagnosability for affine nonlinear systems with multiple faults occurring simultaneously is analyzed.The numerical simulation results are obtained to show the effectiveness of the proposed evaluation scheme of fault diagnosability.展开更多
This paper studies local exponential synchronization of complex delayed networks with switching topology via switched system stability theory. First, by a common unitary matrix, the problem of synchronization is trans...This paper studies local exponential synchronization of complex delayed networks with switching topology via switched system stability theory. First, by a common unitary matrix, the problem of synchronization is transformed into the stability analysis of some linear switched delay systems. Then, when all subnetworks are synchronizable, a delay-dependent sufficient condition is given in terms of linear matrix inequalities （LMIs） which guarantees the solvability of the synchronization problem under an average dwell time scheme. We extend this result to the case that not all subnetworks are synchronizable. It is shown that in addition to average dwell time, if the ratio of the total activation time of synchronizable and non-synchronizable subnetworks satisfy an extra condition, then the problem is also solvable. Two numerical examples of delayed dynamical networks with switching topology are given, which demonstrate the effectiveness of obtained results.展开更多
Objective To research a protein chip method which can simultaneously quantitative detect β-Lactoglobulin （β-L） and Lactoferrin （Lf） at one time. Methods Protein chip printer was used to print both anti-β-L anti...Objective To research a protein chip method which can simultaneously quantitative detect β-Lactoglobulin （β-L） and Lactoferrin （Lf） at one time. Methods Protein chip printer was used to print both anti-β-L antibodies and anti-Lf antibodies on each block of protein chip. And then an improved sandwich detection method was applied while the other two detecting antibodies for the two antigens were added in the block after they were mixed. The detection conditions of the quantitative detection for simultaneous measurement of β-L and Lf with protein chip were optimized and evaluated. Based on these detected conditions, two standard curves of the two proteins were simultaneously established on one protein chip. Finally, the new detection method was evaluated by using the analysis of precision and accuracy. Results By comparison experiment, mouse monoclonal antibodies of the two antigens were chosen as the printing probe. The concentrations of β-L and Lf probes were 0.5 mg/mL and 0.5 mg/mL, respectively, while the titers of detection antibodies both of β-L and Lf were 1：2,000. Intra- and inter-assay variability was between 4.88% and 38.33% for all tests. The regression coefficients of protein chip comparing with ELISA for β-L and Lf were better than 0.734, and both of the two regression coefficients were statistically significant （r = 0.734, t = 2.644, P = 0.038; and r = 0.774, t = 2.998, P = 0.024）. Conclusion A protein chip method of simultaneously quantitative detection for β-L and Lf has been established and this method is worthy in further application.展开更多
A multifunctional integrated microfluidic biochip device was engineered to estimate the activity-toxicity and composition principle of medicine in a cell model in vitro. This biochip could be used for disease cells an...A multifunctional integrated microfluidic biochip device was engineered to estimate the activity-toxicity and composition principle of medicine in a cell model in vitro. This biochip could be used for disease cells and healthy cells in two modules of "Yin-Yang" on the same chip for detecting the medicine efficacytoxicity simultaneously, as well as adjust different gradient ratios of concentration through the Christmas tree structure in both "Yin-Yang" modules autonomously for detecting the best compatibility of medicine in maximum efficacy and minimal toxicity. In the applicability experiment, the best concentration of three chemical compounds including dinatin, diosmetin and cisplatin, were detected using the biochip and traditional 96-cell plate. Biochip assays showed perfect positive correlation compared with the results of traditional 96-cell plate, in addition presented advantages as less detection time and much lower price than the traditional 96-cell plate, which indicated the biochip is both convenient and feasible.Thus, the novel microfluidic chip-based multifunctional integrated system congregated the virtues of high throughput, rapid, sensitive, specific, cost-effective, and similar to the physical environment of the human body, which was especially suitable for the medicine efficacy-toxicity and compatibility evaluation.展开更多
Effective multiple optoelectronic feedback circuits for simultaneously suppressing low-frequency and relaxation oscillation intensity noise in a single-frequency phosphate fiber laser are demonstrated. The forward tra...Effective multiple optoelectronic feedback circuits for simultaneously suppressing low-frequency and relaxation oscillation intensity noise in a single-frequency phosphate fiber laser are demonstrated. The forward transfer function, which relates the laser output intensity to the pump modulations, is measured and analyzed. A custom two-path feedback system operating at different frequency bands is designed to adjust the pump current directly. The relative intensity noise is decreased by 20dB from 0.2 to 5kHz and over lOdB from 5 to lOkHz. The relaxation oscillation peak is suppressed by 22dB. In addition, a long term （24h） laser instability of less than 0.05% is achieved.展开更多
Here,superhydrophobic cuprous oxide(Cu2O)with hierarchical micro/nanosized structures was synthesized via sprayassisted layer by layer assembling.The asprepared superhydrophobic meshes with high contact angle(159.6...Here,superhydrophobic cuprous oxide(Cu2O)with hierarchical micro/nanosized structures was synthesized via sprayassisted layer by layer assembling.The asprepared superhydrophobic meshes with high contact angle(159.6°)and low sliding angle(1°)are covered with Cu_(2)O "coral reef"like micro/nanosized structures.Interestingly,the superhydrophobic mesh surfaces became superhydrophilic again due to the oxidization of Cu_(2)O to CuO by annealing at a higher temperature(300℃).And the superhydrophobic properties would be recovered by heating at 120℃.Furthermore,the superwetting meshes were applied to design a miniature device to separate light or heavy oil from the wateroil mixtures with excellent separation efficiency.These superwetting surfaces by simultaneously sprayassisted layer by layer assembling technique show the potential application in universal oilwater separation.展开更多
The bioavailability of five divalent cationic heavy metals （Pb, Cd, Cu, Zn and Ni） in 10 superficial sediment samples from Baihua Lake was assessed based on the molar ratio of simultaneously extracted metals （SEMs...The bioavailability of five divalent cationic heavy metals （Pb, Cd, Cu, Zn and Ni） in 10 superficial sediment samples from Baihua Lake was assessed based on the molar ratio of simultaneously extracted metals （SEMs） to acid volatile sulfide （AVS）. Atomic absorption spectrometry （AAS） and X-ray powder diffraction （XRD） were used to determine the heavy metal concentrations and examine the mineralogy of the crystalline phases, respectively. The AVS loadings in sediments from Baihua Lake ranged from 64.30 to 350.08 ~rnol/g （dry weight）. The corresponding SEM levels for the sampling sites varied from 1.770 to 14.660 vrnol/g. The molar ratio of SEMs to AVS ranged from 0.014 to 0.084 with a mean value of 0.034. The XRD analysis also confirmed the presence of some metal sulfides in sediments from Baihua Lake. The SEMs/AVS ratios for all sampling sites were significantly lower than 1.0, indicating that AVS in the sediments was sufficient to bind the five heavy metals; thus, these heavy metals are currently not significantly bioavailable to benthic organisms. Comparing the SEMs results to published guideline values for metal toxicity to benthic organisms in sediments, however, suggests that Zn and Ni pose a risk at some sampling locations in Baihua Lake.展开更多
Abstract： There is a high demand for unmanned aerial vehicle （UAV） flight stability when using vi- sion as a detection method for navigation control. To meet such demand, a new path planning meth- od for controllin...Abstract： There is a high demand for unmanned aerial vehicle （UAV） flight stability when using vi- sion as a detection method for navigation control. To meet such demand, a new path planning meth- od for controlling multi-UAVs is studied to reach multi-waypoints simultaneously under the view of visual navigation technology. A model based on the stable-shortest pythagorean-hodograph （PH） curve is established, which could not only satisfy the demands of visual navigation and control law, but also be easy to compute. Based on the model, a planning algorithm to guide multi-UAVs to reach multi-waypoints at the same time without collisions is developed. The simulation results show that the paths have shorter distance and smaller curvature than traditional methods, which could help to avoid collisions.展开更多
Implementing self-sustainable wireless communication systems is urgent and challenging for 5G and 6G technologies.In this paper,we elaborate on a system solution using the programmable metasurface(PMS)for simultaneous...Implementing self-sustainable wireless communication systems is urgent and challenging for 5G and 6G technologies.In this paper,we elaborate on a system solution using the programmable metasurface(PMS)for simultaneous wireless information and power transfers(SWIPT),offering an optimized wireless energy management network.Both transmitting and receiving sides of the proposed solution are presented in detail.On the transmitting side,employing the wireless power transfer(WPT)technique,we present versatile power conveying strategies for near-field or far-field targets,single or multiple targets,and equal or unequal power targets.On the receiving side,utilizing the wireless energy harvesting(WEH)technique,we report our work on multi-functional rectifying metasurfaces that collect the wirelessly transmitted energy and the ambient energy.More importantly,a numerical model based on the plane-wave angular spectrum method is investigated to accurately calculate the radiation fields of PMS in the Fresnel and Fraunhofer regions.With this model,the efficiencies of WPT between the transmitter and the receiver are analyzed.Finally,future research directions are discussed,and integrated PMS for wireless information and wireless power is outlined.展开更多
In the two fairs, the most advanced world level techonologies and products, including computers, electronics parts, individual infor-mation products were shown on 700-more exhibition sites.
We propose a system for simultaneously presenting numerous pieces of video content with absolute time metadata attached for effectively utilizing increasing number of pieces of video content. The proposed stored forma...We propose a system for simultaneously presenting numerous pieces of video content with absolute time metadata attached for effectively utilizing increasing number of pieces of video content. The proposed stored format used for the system is based on the MMT （MPEG （moving picture experts group） media transport） standardized method, which makes it possible to search by absolute time, and it is a format easy to access by HTTP. We implemented software that can simultaneously present multiple video files according to that format. The constructed system was able to provide service within a feasible processing time.展开更多
In this research article,we construct a family of derivative free simultaneous numerical schemes to approximate all real zero of non-linear polynomial equation.We make a comparative analysis of the newly constructed n...In this research article,we construct a family of derivative free simultaneous numerical schemes to approximate all real zero of non-linear polynomial equation.We make a comparative analysis of the newly constructed numerical schemes with a well-known existing simultaneous method for determining all the distinct real zeros of polynomial equations using computer algebra system Mat Lab.Lower bound of convergence of simultaneous schemes is calculated using Mathematica.Global convergence property of the numerical schemes is presented by taking random starting initial approximation and their convergence history are graphically presented.Some real life engineering applications along with some higher degree polynomials are considered as numerical test problems to show performance and efficiency of the derivative free family of numerical methods with comparison of an existing method of same order in literature.Local computational order of convergence,CPU time,graph of computational order of convergence and residual error graphs elaborate efficiency,robustness and authentication of the suggested family of numerical methods in its domain.展开更多
Alkane isomers(mainly C5-C7 alkanes),produced via catalytic isomerization reactions during oil refinement,are important raw chemicals in the petrochemical industry[1].They are used in a broad spectrum of chemical proc...Alkane isomers(mainly C5-C7 alkanes),produced via catalytic isomerization reactions during oil refinement,are important raw chemicals in the petrochemical industry[1].They are used in a broad spectrum of chemical processes,depending on their branching.Specifically,normal alkanes and monobranched isomers are premium ethylene feed,and dibranched isomers are desired components for high-rating gasolines[2].Consequently,the isomers must be separated before further use.展开更多
We study preemptive scheduling on m uniform machines with non-simultaneous available times to minimize the makespan.Each machine has a different speed and a different available time.We first provide a lower bound on t...We study preemptive scheduling on m uniform machines with non-simultaneous available times to minimize the makespan.Each machine has a different speed and a different available time.We first provide a lower bound on the optimal makespan of the problem by converting the real machines to virtual machines that guarantee a machine with an earlier available time having a greater speed at any time.展开更多
基金this paper is funded by Project Information:2023 Guangdong Undergraduate Colleges and Universities Teaching Quality and Teaching Reform Project Construction Project,Project Name:Action Research on Whole-area Nurturing of English Reading Teaching in Universities,Secondary and Primary Schools under the Perspective of Discipline Nurturing.Project serial number:895.
文摘“Five education”is pivotal for students’all-round development.However,primary English teaching currently faces challenges including the superficial implementation of“Five education”.This study employed action research to explore practical methods for integrating English picture book with textbook to implement“Five education”.Through two rounds of iterative action research,a three-stage activity-based teaching path was developed and refined,enabling the progressive infusion of“Five education”objectives across the learning cycle.Findings demonstrated that this integrated approach-particularly when supported by strategies such as picture book background videos and audio-edited narrative connections-effectively deepened the implementation of“Five education”,mitigated student reading fatigue,and significantly improved students’reading fluency and labor initiative,thus provided a replicable practical paradigm for realizing“Five education simultaneously”.
基金financial supports from the National Natural Science Foundation of China(No.51704107)the Department of Education Scientific Research of Hunan Province,China(No.22A0401)the Natural Science Foundation of Hunan Province,China(No.2024JJ7160).
文摘The effects of leaching temperature(60−105°C),NH4Cl concentration(3−7 mol/L),liquid/solid ratio(4:1−12:1 mL/g),stirring speed(150−750 r/min),and leaching time(5−90 min)on the leaching rates of Zn and Pb were investigated.The leaching kinetics of Zn-and Pb-rich fuming dust with a NH4Cl solution was also studied.The leaching rates of Zn and Pb respectively reached 98.2%and 75.6%at leaching temperature of 100°C,an NH4Cl concentration of 7.0 mol/L,a liquid/solid ratio of 10:1 mL/g,a stirring speed of 450 r/min and leaching time of 60 min.The kinetics results indicate that the leaching of Zn and Pb conforms to the shrinking unreacted core model and is controlled by the internal diffusion of NH4Cl through the reacted fuming dust layer and external diffusion of NH4Cl through the leaching solution boundary layer,respectively.The apparent activation energies of Zn and Pb are 23.922 and 19.139 kJ/mol,respectively.This study demonstrates that the use of NH4Cl solution,without ammonia,is an environmentally friendly method for simultaneous extracting Zn and Pb from the fuming dust of lead blast furnace slag.
文摘Correction to:Rare Met.https://doi.org/10.1007/s12598-019-01312-4 In the original publication,in Figure 3,part d has been mistakenly published same as part c.The correct version of Fig.3 is given in this Correction.
基金supported by grants from the National Natural Science Foundation of China (No.91635302)the National Key Research and Development Program of China (2016YFD0100401)+1 种基金the Chinese Academy of Sciences (XDA08010101)the State Key Laboratory of Plant Cell and Chromosome Engineering (PCCEKF-2017-04)
文摘Rice is one of the most important staple food for over half of the world＇s population,and a substantial increase in productivity and quality of rice grain will be required to feed a growing human population.Grain size and shape are the two important components contributing to grain yield and quality,because they impact both yield potential and end-use quality.
基金the Natural Science Foundation of Fujian Province,China(2019J05024)the Education Department Foundation of Fujian Province,China(JAT170091).
文摘Up to present,the problem of the evaluation of fault diagnosability for nonlinear systems has been investigated by many researchers.However,no attempt has been done to evaluate the diagnosability of multiple faults occurring simultaneously for nonlinear systems.This paper proposes a method based on differential geometry theories to solve this problem.Then the evaluation of fault diagnosability for affine nonlinear systems with multiple faults occurring simultaneously is achieved.To deal with the effect of control laws on the evaluation results of fault diagnosability,a design scheme of the evaluation of fault diagnosability is proposed.Then the influence of uncertainties on the evaluation results of fault diagnosability for affine nonlinear systems with multiple faults occurring simultaneously is analyzed.The numerical simulation results are obtained to show the effectiveness of the proposed evaluation scheme of fault diagnosability.
基金the National Natural Science Foundation of China (No.60874024, 60574013).
文摘This paper studies local exponential synchronization of complex delayed networks with switching topology via switched system stability theory. First, by a common unitary matrix, the problem of synchronization is transformed into the stability analysis of some linear switched delay systems. Then, when all subnetworks are synchronizable, a delay-dependent sufficient condition is given in terms of linear matrix inequalities （LMIs） which guarantees the solvability of the synchronization problem under an average dwell time scheme. We extend this result to the case that not all subnetworks are synchronizable. It is shown that in addition to average dwell time, if the ratio of the total activation time of synchronizable and non-synchronizable subnetworks satisfy an extra condition, then the problem is also solvable. Two numerical examples of delayed dynamical networks with switching topology are given, which demonstrate the effectiveness of obtained results.
基金Sponsored by the Young Scholar Scientific Research Foundation of China CDC[2015A202]:The establishment of testing platform of quantitatively detecting main protein of cow milk by using protein chip technique
文摘Objective To research a protein chip method which can simultaneously quantitative detect β-Lactoglobulin （β-L） and Lactoferrin （Lf） at one time. Methods Protein chip printer was used to print both anti-β-L antibodies and anti-Lf antibodies on each block of protein chip. And then an improved sandwich detection method was applied while the other two detecting antibodies for the two antigens were added in the block after they were mixed. The detection conditions of the quantitative detection for simultaneous measurement of β-L and Lf with protein chip were optimized and evaluated. Based on these detected conditions, two standard curves of the two proteins were simultaneously established on one protein chip. Finally, the new detection method was evaluated by using the analysis of precision and accuracy. Results By comparison experiment, mouse monoclonal antibodies of the two antigens were chosen as the printing probe. The concentrations of β-L and Lf probes were 0.5 mg/mL and 0.5 mg/mL, respectively, while the titers of detection antibodies both of β-L and Lf were 1：2,000. Intra- and inter-assay variability was between 4.88% and 38.33% for all tests. The regression coefficients of protein chip comparing with ELISA for β-L and Lf were better than 0.734, and both of the two regression coefficients were statistically significant （r = 0.734, t = 2.644, P = 0.038; and r = 0.774, t = 2.998, P = 0.024）. Conclusion A protein chip method of simultaneously quantitative detection for β-L and Lf has been established and this method is worthy in further application.
文摘A multifunctional integrated microfluidic biochip device was engineered to estimate the activity-toxicity and composition principle of medicine in a cell model in vitro. This biochip could be used for disease cells and healthy cells in two modules of "Yin-Yang" on the same chip for detecting the medicine efficacytoxicity simultaneously, as well as adjust different gradient ratios of concentration through the Christmas tree structure in both "Yin-Yang" modules autonomously for detecting the best compatibility of medicine in maximum efficacy and minimal toxicity. In the applicability experiment, the best concentration of three chemical compounds including dinatin, diosmetin and cisplatin, were detected using the biochip and traditional 96-cell plate. Biochip assays showed perfect positive correlation compared with the results of traditional 96-cell plate, in addition presented advantages as less detection time and much lower price than the traditional 96-cell plate, which indicated the biochip is both convenient and feasible.Thus, the novel microfluidic chip-based multifunctional integrated system congregated the virtues of high throughput, rapid, sensitive, specific, cost-effective, and similar to the physical environment of the human body, which was especially suitable for the medicine efficacy-toxicity and compatibility evaluation.
基金Supported by the National High-Technology Research and Development Program of China under Grant Nos 2013AA031502 and 2014AA041902the National Natural Science Foundation of China under Grant Nos 11174085,51132004,and 51302086+3 种基金the Guangdong Natural Science Foundation under Grant Nos S2011030001349 and S20120011380the China National Funds for Distinguished Young Scientists under Grant No 61325024the Science and Technology Project of Guangdong Province under Grant No 2013B090500028the’Cross and Cooperative’Science and Technology Innovation Team Project of Chinese Academy of Sciences under Grant No 2012-119
文摘Effective multiple optoelectronic feedback circuits for simultaneously suppressing low-frequency and relaxation oscillation intensity noise in a single-frequency phosphate fiber laser are demonstrated. The forward transfer function, which relates the laser output intensity to the pump modulations, is measured and analyzed. A custom two-path feedback system operating at different frequency bands is designed to adjust the pump current directly. The relative intensity noise is decreased by 20dB from 0.2 to 5kHz and over lOdB from 5 to lOkHz. The relaxation oscillation peak is suppressed by 22dB. In addition, a long term （24h） laser instability of less than 0.05% is achieved.
基金The authors gratefully acknowledge financial support from Guangdong Basic and Applied Basic Research Foundation,China(No.2019A15150101011282)Open Funds of National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials(2019008)the Fundamental Research Funds for the Central Universities(21619336).
文摘Here,superhydrophobic cuprous oxide(Cu2O)with hierarchical micro/nanosized structures was synthesized via sprayassisted layer by layer assembling.The asprepared superhydrophobic meshes with high contact angle(159.6°)and low sliding angle(1°)are covered with Cu_(2)O "coral reef"like micro/nanosized structures.Interestingly,the superhydrophobic mesh surfaces became superhydrophilic again due to the oxidization of Cu_(2)O to CuO by annealing at a higher temperature(300℃).And the superhydrophobic properties would be recovered by heating at 120℃.Furthermore,the superwetting meshes were applied to design a miniature device to separate light or heavy oil from the wateroil mixtures with excellent separation efficiency.These superwetting surfaces by simultaneously sprayassisted layer by layer assembling technique show the potential application in universal oilwater separation.
基金Supported by the National Natural Science Foundation of China(No.20967003)the Project of the Government of Guiyang City(No.[2010]5-2)
文摘The bioavailability of five divalent cationic heavy metals （Pb, Cd, Cu, Zn and Ni） in 10 superficial sediment samples from Baihua Lake was assessed based on the molar ratio of simultaneously extracted metals （SEMs） to acid volatile sulfide （AVS）. Atomic absorption spectrometry （AAS） and X-ray powder diffraction （XRD） were used to determine the heavy metal concentrations and examine the mineralogy of the crystalline phases, respectively. The AVS loadings in sediments from Baihua Lake ranged from 64.30 to 350.08 ~rnol/g （dry weight）. The corresponding SEM levels for the sampling sites varied from 1.770 to 14.660 vrnol/g. The molar ratio of SEMs to AVS ranged from 0.014 to 0.084 with a mean value of 0.034. The XRD analysis also confirmed the presence of some metal sulfides in sediments from Baihua Lake. The SEMs/AVS ratios for all sampling sites were significantly lower than 1.0, indicating that AVS in the sediments was sufficient to bind the five heavy metals; thus, these heavy metals are currently not significantly bioavailable to benthic organisms. Comparing the SEMs results to published guideline values for metal toxicity to benthic organisms in sediments, however, suggests that Zn and Ni pose a risk at some sampling locations in Baihua Lake.
文摘Abstract： There is a high demand for unmanned aerial vehicle （UAV） flight stability when using vi- sion as a detection method for navigation control. To meet such demand, a new path planning meth- od for controlling multi-UAVs is studied to reach multi-waypoints simultaneously under the view of visual navigation technology. A model based on the stable-shortest pythagorean-hodograph （PH） curve is established, which could not only satisfy the demands of visual navigation and control law, but also be easy to compute. Based on the model, a planning algorithm to guide multi-UAVs to reach multi-waypoints at the same time without collisions is developed. The simulation results show that the paths have shorter distance and smaller curvature than traditional methods, which could help to avoid collisions.
基金the National Key Research and Development Program of China under Grant Nos.2017YFA0700201,2017YFA0700202,2017YFA0700203,and 2021YFA1401001the 111 Project under Grant No.111⁃2⁃05,National Natural Science Foundation of China under Grant No.62001342+1 种基金Key Research and Development Program of Shaanxi under Grant No.2021TD⁃07Outstanding Youth Science Foundation of Shaanxi Province under Grant No.2019JC⁃15.
文摘Implementing self-sustainable wireless communication systems is urgent and challenging for 5G and 6G technologies.In this paper,we elaborate on a system solution using the programmable metasurface(PMS)for simultaneous wireless information and power transfers(SWIPT),offering an optimized wireless energy management network.Both transmitting and receiving sides of the proposed solution are presented in detail.On the transmitting side,employing the wireless power transfer(WPT)technique,we present versatile power conveying strategies for near-field or far-field targets,single or multiple targets,and equal or unequal power targets.On the receiving side,utilizing the wireless energy harvesting(WEH)technique,we report our work on multi-functional rectifying metasurfaces that collect the wirelessly transmitted energy and the ambient energy.More importantly,a numerical model based on the plane-wave angular spectrum method is investigated to accurately calculate the radiation fields of PMS in the Fresnel and Fraunhofer regions.With this model,the efficiencies of WPT between the transmitter and the receiver are analyzed.Finally,future research directions are discussed,and integrated PMS for wireless information and wireless power is outlined.
文摘In the two fairs, the most advanced world level techonologies and products, including computers, electronics parts, individual infor-mation products were shown on 700-more exhibition sites.
文摘We propose a system for simultaneously presenting numerous pieces of video content with absolute time metadata attached for effectively utilizing increasing number of pieces of video content. The proposed stored format used for the system is based on the MMT （MPEG （moving picture experts group） media transport） standardized method, which makes it possible to search by absolute time, and it is a format easy to access by HTTP. We implemented software that can simultaneously present multiple video files according to that format. The constructed system was able to provide service within a feasible processing time.
文摘In this research article,we construct a family of derivative free simultaneous numerical schemes to approximate all real zero of non-linear polynomial equation.We make a comparative analysis of the newly constructed numerical schemes with a well-known existing simultaneous method for determining all the distinct real zeros of polynomial equations using computer algebra system Mat Lab.Lower bound of convergence of simultaneous schemes is calculated using Mathematica.Global convergence property of the numerical schemes is presented by taking random starting initial approximation and their convergence history are graphically presented.Some real life engineering applications along with some higher degree polynomials are considered as numerical test problems to show performance and efficiency of the derivative free family of numerical methods with comparison of an existing method of same order in literature.Local computational order of convergence,CPU time,graph of computational order of convergence and residual error graphs elaborate efficiency,robustness and authentication of the suggested family of numerical methods in its domain.
基金supported by the Key Program of National Natural Science Foundation of China(22438001)the National Natural Science Foundation of China(22478251,52373212)+1 种基金the Shenzhen Science and Technology Program(KCXFZ20211020163818026)the Shenzhen Polytechnic University Research Fund(6024310024K)。
文摘Alkane isomers(mainly C5-C7 alkanes),produced via catalytic isomerization reactions during oil refinement,are important raw chemicals in the petrochemical industry[1].They are used in a broad spectrum of chemical processes,depending on their branching.Specifically,normal alkanes and monobranched isomers are premium ethylene feed,and dibranched isomers are desired components for high-rating gasolines[2].Consequently,the isomers must be separated before further use.
基金supported by the Zhejiang Provincial Natural Science Foundation of China(Nos.LZ23G010001 and LZ25F020012)the National Natural Science Foundation of China(Nos.62172356 and 61872321)the Ningbo Major Special Projects of the“Science and Technology Innovation 2025”(No.2024Z122)。
文摘We study preemptive scheduling on m uniform machines with non-simultaneous available times to minimize the makespan.Each machine has a different speed and a different available time.We first provide a lower bound on the optimal makespan of the problem by converting the real machines to virtual machines that guarantee a machine with an earlier available time having a greater speed at any time.
