It is undeniable that wireless communication technology has become a very important component of modern society. One aspect of modern society in which application of wireless communication technologies has tremendous ...It is undeniable that wireless communication technology has become a very important component of modern society. One aspect of modern society in which application of wireless communication technologies has tremendous potential is in agricultural production. This is especially true in the area of sensing and transmission of relevant farming information such as weather, crop development, water quantity and quality, among others, which would allow farmers to make more accurate and timely farming decisions. A good example would be the application of wireless communication technology to transmit soil moisture data in real time to help farmers make irrigation scheduling decisions. Although many systems are commercially available for soil moisture monitoring, there are still many important factors, such as cost, limiting widespread adoption of this technology among growers. Our objective in this study was, therefore, to develop and test an affordable wireless communication system for monitoring soil moisture using Decagon EC-5 sensors. The new system uses Arduino-compatible microcontrollers and communication systems to sample and transmit values from four Decagon EC-5 soil moisture sensors. Developing the system required conducting lab calibrations for the EC-5 sensors for the microcontroller operating in either 10-bit or 12-bit analog-to-digital converter (ADC) resolution. The system was successfully tested in the field and reliably collected and transmitted data from a wheat field for more than two months.展开更多
The utilization of phosphors that achieve full-spectrum lighting has emerged as a prevailing trend in the advancement of white light-emitting diode(WLED)lighting.In this study,we successfully prepared a novel green ph...The utilization of phosphors that achieve full-spectrum lighting has emerged as a prevailing trend in the advancement of white light-emitting diode(WLED)lighting.In this study,we successfully prepared a novel green phosphor Ba_(2)Sc_(2)((BO_(3))_(2)B_(2)O_(5)):Ce^(3+)(BSBO:Ce^(3+))that can be utilized for full-spectrum lighting and low-temperature sensors.BSBO:Ce^(3+)exhibits a broad-band excitation spectrum centered at 410 nm,and a broad-band emission spectrum centered at 525 nm.The internal and external quantum efficiencies of BSBO:Ce^(3+)are 99%and 49%,respectively.The thermal stability of BSBO:Ce^(3+)can be improved by substituting partial Sc atoms with smaller cations.The thermal quenching mechanism of BSBO:Ce^(3+)and the lattice occupancy of Ce ions in BSBO are discussed in detail.Furthermore,by combining the green phosphor BSBO:Ce^(3+),the commercial blue phosphor and the red phosphor on a 405 nm chip,a white light source was obtained with a high average color rendering index(CRI)of 96.6,a low correlated color temperature(CCT)of 3988 K,and a high luminous efficacy of 88.0 Im/W.The lu-minous efficacy of the WLED exhibits negligible degradation during the 1000 h light aging experiment.What's more,an emission peak at 468 nm appears when excited at 352 nm and 80 K,however,the relative intensity of the peaks at 468 and 525 nm gradually weakens with increasing temperature,indicating the potential of this material as a low-temperature sensor.展开更多
A pseudorotaxane and its polypseudorotaxanes formed between pillar[5]arene moieties and noctylpyrazinium cations as novel fluorescent sensors for the selective detection of halogen ions were reported.A collapse of the...A pseudorotaxane and its polypseudorotaxanes formed between pillar[5]arene moieties and noctylpyrazinium cations as novel fluorescent sensors for the selective detection of halogen ions were reported.A collapse of these pillar[5]arene-based pseudorotaxanes and polypseudorotaxanes occurred upon the addition of Cl,Br,and I（tetrabutylammonium salts）,respectively,leading to their fluorescence recovery.The fluorescence enhancement of the pseudorotaxane and the polypseudorotaxanes increases in the order of I展开更多
The macrocyclic ligand,15-crown-5,was used as an ionophore for fabrication of a polyvinyl chloride（PVC） based membrane sensor for Ag（Ⅰ） cation.For construction of the Ag（Ⅰ） cation selective electrode the best ...The macrocyclic ligand,15-crown-5,was used as an ionophore for fabrication of a polyvinyl chloride（PVC） based membrane sensor for Ag（Ⅰ） cation.For construction of the Ag（Ⅰ） cation selective electrode the best response characteristics were obtained using the composition： 15-crown-5/PVC/o-nitrophenyloctylether（NPOE）/sodium tetraphenyl borate（NaTPB） in the percentage ratio of 5.6/30/60.5/3.9（w/w/w/w）.The electrochemical sensor shows a linear dynamic range 1.0 10 7–1.0 10 1mol/L and a Nernstian slope of 58.9 0.5 mV/decade with a detection limit of 8.09 10 8mol/L for Ag（Ⅰ） cation.It has a fast response time of 〈10 s and can be used for at least 8 weeks without any considerable divergences in its potential response.It was successfully used as an indicator electrode in potentiometric titration of Ag（Ⅰ）cation with I and Cl anions and also for the determination of this metal cation in radiology waste water.展开更多
Nowadays,the widespread application of 5G has promoted rapid development in different areas,particularly in the Internet of Things(IoT),where 5G provides the advantages of higher data transfer rate,lower latency,and w...Nowadays,the widespread application of 5G has promoted rapid development in different areas,particularly in the Internet of Things(IoT),where 5G provides the advantages of higher data transfer rate,lower latency,and widespread connections.Wireless sensor networks(WSNs),which comprise various sensors,are crucial components of IoT.The main functions of WSN include providing users with real-time monitoring information,deploying regional information collection,and synchronizing with the Internet.Security in WSNs is becoming increasingly essential because of the across-the-board nature of wireless technology in many fields.Recently,Yu et al.proposed a user authentication protocol forWSN.However,their design is vulnerable to sensor capture and temporary information disclosure attacks.Thus,in this study,an improved protocol called PSAP-WSNis proposed.The security of PSAP-WSN is demonstrated by employing the ROR model,BAN logic,and ProVerif tool for the analysis.The experimental evaluation shows that our design is more efficient and suitable forWSN environments.展开更多
In the past decade,people have conducted extensive research on the synthesis and application properties of various functionalized pillararenes.Pillararenes show good application prospects in the field of sensors due t...In the past decade,people have conducted extensive research on the synthesis and application properties of various functionalized pillararenes.Pillararenes show good application prospects in the field of sensors due to the rich host-vip recognition in their rigid electron-rich cavities.However,most reported pillararenes are functionalized by alkoxy modification,which results in poor charge transfer nature and weak fluorescence response.A π-conjugated charge-transfer system P5BN was obtained by introducing electron-donating triarylamine(Ar_(3)N)and electron-deficient triarylborane(Ar_(3)B)into pillar[5]arene skeleton,which significantly improved its luminescence behavior and was further used for fluorescence detection applications.The molecular structure showed that P5BN provided a good macrocyclic cavity to encapsulate amino acids molecules of suitable size.It was found that P5BN,as a fluorescent sensor,showed a highly sensitive and selective response to L-arginine(L-Arg),resulting in a significant enhancement of the fluorescence at 408 nm of P5BN with the lowest detection concentration being 2.21×10^(-8) mol/L.The recognition mechanism was demonstrated through experiments and DFT theoretical calculations.展开更多
文摘It is undeniable that wireless communication technology has become a very important component of modern society. One aspect of modern society in which application of wireless communication technologies has tremendous potential is in agricultural production. This is especially true in the area of sensing and transmission of relevant farming information such as weather, crop development, water quantity and quality, among others, which would allow farmers to make more accurate and timely farming decisions. A good example would be the application of wireless communication technology to transmit soil moisture data in real time to help farmers make irrigation scheduling decisions. Although many systems are commercially available for soil moisture monitoring, there are still many important factors, such as cost, limiting widespread adoption of this technology among growers. Our objective in this study was, therefore, to develop and test an affordable wireless communication system for monitoring soil moisture using Decagon EC-5 sensors. The new system uses Arduino-compatible microcontrollers and communication systems to sample and transmit values from four Decagon EC-5 soil moisture sensors. Developing the system required conducting lab calibrations for the EC-5 sensors for the microcontroller operating in either 10-bit or 12-bit analog-to-digital converter (ADC) resolution. The system was successfully tested in the field and reliably collected and transmitted data from a wheat field for more than two months.
基金the National Natural Science Foundation of China(22003035,21963006,22073061)the Project of Shaanxi Province Youth Science and Technology New Star(2023KJXX-076)the National Training Program of Innovation and Entrepreneurship for Undergraduates(202314390018)。
文摘The utilization of phosphors that achieve full-spectrum lighting has emerged as a prevailing trend in the advancement of white light-emitting diode(WLED)lighting.In this study,we successfully prepared a novel green phosphor Ba_(2)Sc_(2)((BO_(3))_(2)B_(2)O_(5)):Ce^(3+)(BSBO:Ce^(3+))that can be utilized for full-spectrum lighting and low-temperature sensors.BSBO:Ce^(3+)exhibits a broad-band excitation spectrum centered at 410 nm,and a broad-band emission spectrum centered at 525 nm.The internal and external quantum efficiencies of BSBO:Ce^(3+)are 99%and 49%,respectively.The thermal stability of BSBO:Ce^(3+)can be improved by substituting partial Sc atoms with smaller cations.The thermal quenching mechanism of BSBO:Ce^(3+)and the lattice occupancy of Ce ions in BSBO are discussed in detail.Furthermore,by combining the green phosphor BSBO:Ce^(3+),the commercial blue phosphor and the red phosphor on a 405 nm chip,a white light source was obtained with a high average color rendering index(CRI)of 96.6,a low correlated color temperature(CCT)of 3988 K,and a high luminous efficacy of 88.0 Im/W.The lu-minous efficacy of the WLED exhibits negligible degradation during the 1000 h light aging experiment.What's more,an emission peak at 468 nm appears when excited at 352 nm and 80 K,however,the relative intensity of the peaks at 468 and 525 nm gradually weakens with increasing temperature,indicating the potential of this material as a low-temperature sensor.
基金the financial support of the National Natural Science Foundation of China (No. 21202083)Natural Science Foundation of Jiangsu (Nos. BK2011055, BK2011551)the China Postdoctoral Science Foundation (No. 2012M511717)
文摘A pseudorotaxane and its polypseudorotaxanes formed between pillar[5]arene moieties and noctylpyrazinium cations as novel fluorescent sensors for the selective detection of halogen ions were reported.A collapse of these pillar[5]arene-based pseudorotaxanes and polypseudorotaxanes occurred upon the addition of Cl,Br,and I（tetrabutylammonium salts）,respectively,leading to their fluorescence recovery.The fluorescence enhancement of the pseudorotaxane and the polypseudorotaxanes increases in the order of I
文摘The macrocyclic ligand,15-crown-5,was used as an ionophore for fabrication of a polyvinyl chloride（PVC） based membrane sensor for Ag（Ⅰ） cation.For construction of the Ag（Ⅰ） cation selective electrode the best response characteristics were obtained using the composition： 15-crown-5/PVC/o-nitrophenyloctylether（NPOE）/sodium tetraphenyl borate（NaTPB） in the percentage ratio of 5.6/30/60.5/3.9（w/w/w/w）.The electrochemical sensor shows a linear dynamic range 1.0 10 7–1.0 10 1mol/L and a Nernstian slope of 58.9 0.5 mV/decade with a detection limit of 8.09 10 8mol/L for Ag（Ⅰ） cation.It has a fast response time of 〈10 s and can be used for at least 8 weeks without any considerable divergences in its potential response.It was successfully used as an indicator electrode in potentiometric titration of Ag（Ⅰ）cation with I and Cl anions and also for the determination of this metal cation in radiology waste water.
文摘Nowadays,the widespread application of 5G has promoted rapid development in different areas,particularly in the Internet of Things(IoT),where 5G provides the advantages of higher data transfer rate,lower latency,and widespread connections.Wireless sensor networks(WSNs),which comprise various sensors,are crucial components of IoT.The main functions of WSN include providing users with real-time monitoring information,deploying regional information collection,and synchronizing with the Internet.Security in WSNs is becoming increasingly essential because of the across-the-board nature of wireless technology in many fields.Recently,Yu et al.proposed a user authentication protocol forWSN.However,their design is vulnerable to sensor capture and temporary information disclosure attacks.Thus,in this study,an improved protocol called PSAP-WSNis proposed.The security of PSAP-WSN is demonstrated by employing the ROR model,BAN logic,and ProVerif tool for the analysis.The experimental evaluation shows that our design is more efficient and suitable forWSN environments.
文摘In the past decade,people have conducted extensive research on the synthesis and application properties of various functionalized pillararenes.Pillararenes show good application prospects in the field of sensors due to the rich host-vip recognition in their rigid electron-rich cavities.However,most reported pillararenes are functionalized by alkoxy modification,which results in poor charge transfer nature and weak fluorescence response.A π-conjugated charge-transfer system P5BN was obtained by introducing electron-donating triarylamine(Ar_(3)N)and electron-deficient triarylborane(Ar_(3)B)into pillar[5]arene skeleton,which significantly improved its luminescence behavior and was further used for fluorescence detection applications.The molecular structure showed that P5BN provided a good macrocyclic cavity to encapsulate amino acids molecules of suitable size.It was found that P5BN,as a fluorescent sensor,showed a highly sensitive and selective response to L-arginine(L-Arg),resulting in a significant enhancement of the fluorescence at 408 nm of P5BN with the lowest detection concentration being 2.21×10^(-8) mol/L.The recognition mechanism was demonstrated through experiments and DFT theoretical calculations.
