Green hydrogen from electrolysis of water has attracted widespread attention as a renewable power source.Among several hydrogen production methods,it has become the most promising technology.However,there is no large-...Green hydrogen from electrolysis of water has attracted widespread attention as a renewable power source.Among several hydrogen production methods,it has become the most promising technology.However,there is no large-scale renewable hydrogen production system currently that can compete with conventional fossil fuel hydrogen production.Renewable energy electrocatalytic water splitting is an ideal production technology with environmental cleanliness protection and good hydrogen purity,which meet the requirements of future development.This review summarizes and introduces the current status of hydrogen production by water splitting from three aspects:electricity,catalyst and electrolyte.In particular,the present situation and the latest progress of the key sources of power,catalytic materials and electrolyzers for electrocatalytic water splitting are introduced.Finally,the problems of hydrogen generation from electrolytic water splitting and directions of next-generation green hydrogen in the future are discussed and outlooked.It is expected that this review will have an important impact on the field of hydrogen production from water.展开更多
The degradation of phenol by pulsed discharge plasma above a liquid surface(APDP) and under a liquid surface(UPDP) was compared.The effects of discharge voltage,discharge distance,initial solution conductivity and ini...The degradation of phenol by pulsed discharge plasma above a liquid surface(APDP) and under a liquid surface(UPDP) was compared.The effects of discharge voltage,discharge distance,initial solution conductivity and initial p H on the removal of phenol were studied.It was concluded that the removal of phenol increases with increasing discharge voltage and with decreasing discharge distance in both APDP and UPDP systems.An increase in the initial solution’s conductivity has a positive effect in the APDP system but a negative effect in the UPDP system.In addition,alkaline conditions are conducive to the degradation of phenol in the APDP system,while acidic conditions are conducive in the UPDP system.Free radical quenching experiments revealed that ·O-2has an important influence on the degradation of phenol in the APDP system,while ·OH plays a key role in the UPDP system.This paper verifies the differences in the two discharge methods in terms of phenol removal.展开更多
This mini-review highlights selectively the recent research progress in the composites of Li Fe PO4 and graphene. In particularly, the different fabrication protocols, and the electrochemical performance of the compos...This mini-review highlights selectively the recent research progress in the composites of Li Fe PO4 and graphene. In particularly, the different fabrication protocols, and the electrochemical performance of the composites are summarized in detail. The structural and morphology characters of graphene sheets that may affect the property of the composites are discussed briefly. The possible ongoing researches in area are speculated upon.展开更多
N-doped coaxial CNTs@α-Fe_2O_3@C nanofibers have been successfully synthesized according to a facile solvothermal/hydrothermal method. The obtained CNTs@α-Fe_2O_3@C nanofibers composites exhibited spe- cial three-di...N-doped coaxial CNTs@α-Fe_2O_3@C nanofibers have been successfully synthesized according to a facile solvothermal/hydrothermal method. The obtained CNTs@α-Fe_2O_3@C nanofibers composites exhibited spe- cial three-dimensional (3-D) network structure, which endows they promising candidate for anode ma- terials of lithium ion battery. The coaxial property of CNTs@α-Fe_2O_3@C nanofibers could significantly improve the cycling and rate performance owing to the acceleration of charge/electron transfer, improve- ment of conductivity, maintaining of structural integrity and inhibiting the aggregation. The α-Fe_2O_3 nanoparticles with small size and high percentage of N-doped amount could further improve the elec- trochemical performance. As for the CNTs@α-Fe_2O_3@C nanofibers, the capacity presented a high value of 1255.4 mAh/g at 0.1 C, and retained at 1213.4 mAh/g after 60 cycles. Even at high rate of 5 C, the ca- pacity still exhibited as high as 319 mAh/g. The results indicated that the synthesized N-doped coaxial CNTs@α-Fe_2O_3@C nanofibers exhibited high cvcling and rate oerformance.展开更多
In this study, the effect of activated peroxydisulfate(PDS) by dielectric barrier discharge(DBD) plasma and activated carbon(HGAC) on the removal of acid orange Ⅱ(AOⅡ) was investigated. The effects of applied voltag...In this study, the effect of activated peroxydisulfate(PDS) by dielectric barrier discharge(DBD) plasma and activated carbon(HGAC) on the removal of acid orange Ⅱ(AOⅡ) was investigated. The effects of applied voltage, PDS dosage, HGAC dosage, initial pH value, and inorganic anions on the removal rate of AOⅡ were discussed. The main free radicals degrading azo dyes during the experiment were also studied. Experimental results show that the removal rate of AOⅡ in DBD/HGAC/PDS synergistic system is much higher than that in the single system. With the applied voltage of 16 kV, HGAC dosage of 1 g l-1, PDS and AOⅡ molar ratio of 200:1, initial pH value of 5.4 and concentration of AOⅡ solution of 20 mg l-1, the removal rate of AOⅡ reached 97.6% in DBD/HGAC/PDS process after 28 min of reaction.Acidic and neutral conditions are beneficial for AOⅡ removal. Sulfate and hydroxyl radicals play an important role in the removal of AOⅡ. Inorganic anions are not conducive to the removal of AOⅡ.展开更多
In order to improve the circuit complexity and reduce the long latency of B-1 operations,a novel B-1 operation in Galois Field GF(24)is presented and the corresponding systolic realization based on multiple-valued log...In order to improve the circuit complexity and reduce the long latency of B-1 operations,a novel B-1 operation in Galois Field GF(24)is presented and the corresponding systolic realization based on multiple-valued logic(MVL)is proposed.The systolic structure employs multiplevalued current mode(MVCM)by using dynamic source-coupled logic(SCL)to reduce the initial delay and the transistor and wire counts.The performance is evaluated by HSPICE simulation in 0.18μm CMOS technology and a comparison is conducted between our proposed implementation and those reported in the literature.The initial delay and the sum of transistors and wires in our MVL design are about 43%and 13%lower,respectively,in comparison with other corresponding binary CMOS implementations.The systolic architecture proposed is simple,regular,and modular,well suited for very large scale integration(VLSI)implementations.The combination of MVCM circuits and relevant algorithms based on MVL seems to be a potential solution for high performance arithmetic operations in GF(2k).展开更多
Antibiotic-resistant bacteria contamination in environments imposes great threats to human life health.This research aims to develop novel targeted antibacterial biochars for achieving high selectivity to kill pathoge...Antibiotic-resistant bacteria contamination in environments imposes great threats to human life health.This research aims to develop novel targeted antibacterial biochars for achieving high selectivity to kill pathogenic Escherichia coli(E.coli).The glycopolymer N-halamine-modified biochars(i.e.,BCPMA-Cl)were synthesized by the modification of biochars with poly[2-(methacrylamido)glucopyranose-coacrylamide](P(MAG-co-AM),followed by chlorination treatment.Based on the results of FTIR,turbidity,XPS,and UV–vis,BCPMA-Cl was successfully synthesized and demonstrated to be able to eliminate Staphylococcus aureus(S.aureus)and E.coli.Especially,BCPMA-Cl possessed extremely potent to specific-killing 10^(4) CFU·ml^(-1) of E.coli with lower hemolytic activity(<5%).Additionally,the antibacterial mechanisms of BCPMA-Cl against bacteria were contact-killing and release-killing contributed by active chlorine(i.e.,Cl^(+)).Therefore,this work provided a cost-effective and facile approach for preparation of functional biochars used for bacteria-specific therapeutic applications via livestock pollutants as well as showing a promising strategy to avoid bacterial resistance.展开更多
A polysilicon separated CMOS Schottky barrier diode is designed and tested in this study.By replacing the shallow trench isolation(STI)of a ploy ring,the series resistances of Schottky diodes are reduced,leading to ...A polysilicon separated CMOS Schottky barrier diode is designed and tested in this study.By replacing the shallow trench isolation(STI)of a ploy ring,the series resistances of Schottky diodes are reduced,leading to an improvement in cut-off frequencies.The device structure is detailed and a device model is developed.Our analysis on the device shows that the cut-off frequency increases with the decreasing of the Schottky contact area.Based on this observation,the Schottky contact area is set to0.38×0.38μm^2,which is the minimum contact diffusion area allowed by the process flow.The distance between the anode and the cathode is also discussed.Diodes with different dimensions are fabricated and measured.Through extensive measurements,the optimum dimensions are obtained.Bondpads with a reduced area are used to improve the measurement accuracy.The measurement results show that these diodes can achieve a cut-off frequency of 1.5 THz.Thus,it is possible to use these diodes in THz detection.展开更多
The concept of difference and sum co-array(DSCA)has become a new design idea for planar sparse arrays.Inspired by the shifting invariance property of DSCA,a specific configuration named here as the improved L-shaped a...The concept of difference and sum co-array(DSCA)has become a new design idea for planar sparse arrays.Inspired by the shifting invariance property of DSCA,a specific configuration named here as the improved L-shaped array is proposed.Compared to other traditional 2D sparse array configurations such as 2D nested arrays and hourglass arrays,the proposed configuration has larger central consecutive ranges in its DSCA,thus increasing the DOF.At the same time,the mutual coupling effect is also reduced due to the enlarged spacing between the adjacent sensors.Simulations further demonstrate the superiority of the proposed arrays in terms of detection performance and estimation accuracy.展开更多
A new AB^2 operation in Galois Field GF(24)is presented and its systolic realization based on multiple-valued logic(MVL)is proposed.The systolic structure of the operation employs multiple-valued current mode(MVCM)by ...A new AB^2 operation in Galois Field GF(24)is presented and its systolic realization based on multiple-valued logic(MVL)is proposed.The systolic structure of the operation employs multiple-valued current mode(MVCM)by using dynamic source-coupled logic(SCL)to reduce the transistor and wire counts,and the initial delay.The performance is evaluated by HSPICE simulation with 0.18.μm CMOS technology.A comparison is conducted between our proposed implementation and those reported in the literature.The transistor counts,the wire counts and the initial delay in our MVL design show savings of about 23%,45%,and 72%,in comparison with the corresponding binary CMOS implementation.The systolic architecture proposed is simple,regular,and modular,well suited for very large scale integration(VLSI)implementation.The combination of MVCM circuits and relevant algorithms based on MVL seems to be a potential solution for high performance arithmetic operations in GF(2^k).展开更多
In recent years,the fast-charging capability of the batteries is highly required,especially used for electric vehicles[1-4].Thus,the commercialized lithium-ion batteries(LIBs)which can be rapidly charged and stably cy...In recent years,the fast-charging capability of the batteries is highly required,especially used for electric vehicles[1-4].Thus,the commercialized lithium-ion batteries(LIBs)which can be rapidly charged and stably cycled have a huge market prospect[5-7].However,the Li+transmission rate inside the electrode material/interface is sluggish in fast-charge condition,which usually leads to battery impedance increase,Li metal deposition,and electrolyte decomposition.展开更多
Over the last 10 years,the China Geological Survey has deployed 137 slim-hole shale gas geological exploration wells for coring entire wellbores.These wells are primarily located in new blocks and geological formation...Over the last 10 years,the China Geological Survey has deployed 137 slim-hole shale gas geological exploration wells for coring entire wellbores.These wells are primarily located in new blocks and geological formations where neighboring well data are insufficient,beyond the scope of developed oil fields in China,or outside of oil and gas company mining-right areas.The drilling rig equipment,coring tools,and core drill bits of slim-hole shale gas drilling technology are different from those associated with traditional petroleum drilling.Many studies have been conducted on non-coring slim-hole drilling technology.This paper focuses on coring technology and drilling safety,summarizing a set of high-efficiency shale gas drilling equipment and technology systems based on geological drilling equipment and techniques(that can be used for solid mineral exploration).We report on:1)an improved vertical shaft drilling rig adapted to shale gas well control safety;2)high-efficiency core drilling techniques,focusing on coring tools,and techniques incorporating an inverted tower drilling tool combination,air circulation follow-through technology,and expanded casing technology;3)research progress on high-efficiency core drill bits,including non-planar tooth polycrystalline diamond compact bits and impregnated diamond core bits,along with their application effects.This research provides substantial advances in drill-core technology and improvements in exploration efficiency.Moreover,it provides a reference frame for well structural design and selection of construction technology for shale gas exploration drilling projects.展开更多
OBJECTIVE: To explore the long-term effects and pain relief mechanism of acupotomy by observing changes in nitric oxide synthase (NOS) and beta-en- dorphin (~3-EP) in the hypothalamus, spinal cord, and peripheral...OBJECTIVE: To explore the long-term effects and pain relief mechanism of acupotomy by observing changes in nitric oxide synthase (NOS) and beta-en- dorphin (~3-EP) in the hypothalamus, spinal cord, and peripheral blood of rats with third lumbar ver- tebrae (L3) transverse process syndrome. METHODS: Twenty-eight SD rats were randomly as- signed to normal, model, electroacupuncture (EA), and acupotomy group. The last three groups were put through an operation to emulate L3 transverse process syndrome. Fourteen days after the simulation operation, EA and acupotomy treatments were applied to the respective groups. Fifty-six days afterthe simulation operation, biochemistry tests and enzyme-linked immunosorbent assay were used to measure NOS and 13-EP in the hypothalamus, spinal cord, and peripheral blood. RESULTS: Rats with the simulation operation showed significantly higher levels of NOS and II3-EP in the hypothalamus, spinal cord, and peripheral blood than those in the normal group. The EA and acupotomy groups had significantly lower levels of NOS and β-EP than those in the model group. There was no statistical difference between the EA and acupotomy groups. CONCLUSION: EA and acupotomy treatments significantly lowered NOS and β-EP levels in the hypothalamus, spinal cord, and peripheral blood and alleviated L3 transverse process syndrome.展开更多
Background Overseas imported dengue fever is an important factor in local outbreaks of this disease in the mainland of China.To better prevent and control such local outbreaks,the epidemiological characteristics and t...Background Overseas imported dengue fever is an important factor in local outbreaks of this disease in the mainland of China.To better prevent and control such local outbreaks,the epidemiological characteristics and temporal-spatial distribution of overseas imported dengue fever cases in provincial-level administrative divisions(PLADs)where dengue fever is outbreak in the mainland of China were explored.Methods Using the Chinese National Notifiable Infectious Disease Reporting Information System(CNNDS),we identified overseas imported dengue fever cases in dengue fever outbreak areas in the mainland of China from 2005 to 2019 to draw the epidemic curve and population characteristic distribution of overseas imported cases in each PLAD.Based on spatial autocorrelation analysis of ArcGIS 10.5 and temporal-spatial scanning analysis of SaTScan 9.5,we analyzed the temporal-spatial distribution of overseas imported dengue fever in dengue fever outbreak areas in the mainland of China.Results A total of 11,407 imported cases,mainly from Southeast Asia,were recorded from 2005 to 2019 in these 13 PLADs.Of which 62.1%were imported into Yunnan and Guangdong Provinces.Among the imported cases,there were more males than females,mainly from the 21–50 age group.The hot spots were concentrated in parts of Yunnan,Guangdong and Fujian Provinces.We found the cluster of infected areas were expanding northward.Conclusions Based on the analysis of overseas imported dengue cases in 13 PLADs of the mainland of China from 2005 to 2019,we obtained the epidemiological characteristics and spatial distribution of imported dengue cases.Border controls need to pay attention to key population sectors,such as 21–50 years old men and education of key populations on dengue prevention.There is a need to improve the awareness of the prevention and control of imported cases in border areas.At the same time,northern regions cannot relax their vigilance.展开更多
The rich porous structure,high surface area and surface doping make nitrogen doping mesoporous carbon materials(N-MPC)attractive in various areas,including adsorption separation,electrochemical energy storage,catalysi...The rich porous structure,high surface area and surface doping make nitrogen doping mesoporous carbon materials(N-MPC)attractive in various areas,including adsorption separation,electrochemical energy storage,catalysis and other fields.Herein,polyvinylpyrrolidone(PVP)is introduced into the polymerization process of assembly of phenol/formaldehyde(PF)resin by means of hydrogen bonds and electrostatic interaction,which not only leads to the formation of uniform mesopores,but also leads to the increase of specific surface area and nitrogen doping.The amount of PVP and annealing temperature has no obvious effect on morphology,but subsequently has effect on the specific surface area and pore volume.When appropriate PVP dosage and annealing temperature are adopted,the obtained N-MPC shows abundant mesoporous,high surface area and suitable nitrogen doping.As electrode materials in supercapacitor,the N-MPC shows good performance with high capacitance good stability and rate performance,presenting its excellent promising in energy storage.展开更多
The support elderly parents receive from their grown-up children and the care they provide for grandchildren reflect the intergenerational relationships in Chinese families.Using data on only-child families in urban C...The support elderly parents receive from their grown-up children and the care they provide for grandchildren reflect the intergenerational relationships in Chinese families.Using data on only-child families in urban China from a 2015 survey conducted by the Institute of Population and Labor Economics,Chinese Academy of Social Sciences,this paper studies the status of care provided for grandchildren by parents of first-generation only-child in urban China and considers the effects this support has on the elderly.The data shows that over 80%of only-children parents have cared for their grandchildren.Most only-children also provide support for their elderly parents.Care for grandchildren provided by grandparents increases the economic and housekeeping support for the elderly provided by only-children.Only-children are the main beneficiaries of the intergenerational support that comes from the care for grandchildren provided by elderly parents.If the elderly parents have adequate retirement income and have little or no need for financial support,such intergenerational support resembles“altruism”.However,if the elderly parents do not have adequate retirement income,the satisfaction of their needs depends on resources like time and money available to their only-children.展开更多
This paper studies the status of empty nest only-child families in urban China,using data about these families taken from a 2015 survey conducted by the Institute of Population and Labor Economics,Chinese Academy of S...This paper studies the status of empty nest only-child families in urban China,using data about these families taken from a 2015 survey conducted by the Institute of Population and Labor Economics,Chinese Academy of Social Sciences.Factors that determine the timing of empty nest periods and their duration for only-child parents are also analyzed.The data shows that more than half of the only-child parents surveyed in 2015 lived in empty nests.Some of these parents had been empty-nesters for as many as 25 years.During the life cycle of families,the empty nest status of elderly only-child parents shows different characteristics at different stages,as the only-children begin attending universities,start to work,get married,and have children of their own.There are empty nest periods in only-child families when the only-child leaves the parents for several years and periods when the child returns home and lives with parents for years.The living arrangements of only-child parents depend mainly on changes in the life needs of their only-children.Intergenerational support is focused on meeting the needs of only-children.展开更多
基金supported by the National Natural Science Foundation of China(U23A20573,U23A20140,22109038)the Starting Research Funds of Hebei University of Science and Technology,Hebei Natural Science Foundation(D2022208001)+1 种基金the S&T Program of Hebei(23314401D)Hebei Pharmaceutical and Chemical Technology Innovation Center(225676121H).
文摘Green hydrogen from electrolysis of water has attracted widespread attention as a renewable power source.Among several hydrogen production methods,it has become the most promising technology.However,there is no large-scale renewable hydrogen production system currently that can compete with conventional fossil fuel hydrogen production.Renewable energy electrocatalytic water splitting is an ideal production technology with environmental cleanliness protection and good hydrogen purity,which meet the requirements of future development.This review summarizes and introduces the current status of hydrogen production by water splitting from three aspects:electricity,catalyst and electrolyte.In particular,the present situation and the latest progress of the key sources of power,catalytic materials and electrolyzers for electrocatalytic water splitting are introduced.Finally,the problems of hydrogen generation from electrolytic water splitting and directions of next-generation green hydrogen in the future are discussed and outlooked.It is expected that this review will have an important impact on the field of hydrogen production from water.
基金the financial support from National Natural Science Foundation of China (No. 51707093)。
文摘The degradation of phenol by pulsed discharge plasma above a liquid surface(APDP) and under a liquid surface(UPDP) was compared.The effects of discharge voltage,discharge distance,initial solution conductivity and initial p H on the removal of phenol were studied.It was concluded that the removal of phenol increases with increasing discharge voltage and with decreasing discharge distance in both APDP and UPDP systems.An increase in the initial solution’s conductivity has a positive effect in the APDP system but a negative effect in the UPDP system.In addition,alkaline conditions are conducive to the degradation of phenol in the APDP system,while acidic conditions are conducive in the UPDP system.Free radical quenching experiments revealed that ·O-2has an important influence on the degradation of phenol in the APDP system,while ·OH plays a key role in the UPDP system.This paper verifies the differences in the two discharge methods in terms of phenol removal.
基金the Science and Technology Commission of Shanghai Municipality (No. 12nm0503500)the National Science Foundation of China (Nos. 21376148, 11374205)
文摘This mini-review highlights selectively the recent research progress in the composites of Li Fe PO4 and graphene. In particularly, the different fabrication protocols, and the electrochemical performance of the composites are summarized in detail. The structural and morphology characters of graphene sheets that may affect the property of the composites are discussed briefly. The possible ongoing researches in area are speculated upon.
基金the National Natural Science Foundation of China (No. 91634108, 21376148 and 61503246)National Key Program(2017FYA0205300)
文摘N-doped coaxial CNTs@α-Fe_2O_3@C nanofibers have been successfully synthesized according to a facile solvothermal/hydrothermal method. The obtained CNTs@α-Fe_2O_3@C nanofibers composites exhibited spe- cial three-dimensional (3-D) network structure, which endows they promising candidate for anode ma- terials of lithium ion battery. The coaxial property of CNTs@α-Fe_2O_3@C nanofibers could significantly improve the cycling and rate performance owing to the acceleration of charge/electron transfer, improve- ment of conductivity, maintaining of structural integrity and inhibiting the aggregation. The α-Fe_2O_3 nanoparticles with small size and high percentage of N-doped amount could further improve the elec- trochemical performance. As for the CNTs@α-Fe_2O_3@C nanofibers, the capacity presented a high value of 1255.4 mAh/g at 0.1 C, and retained at 1213.4 mAh/g after 60 cycles. Even at high rate of 5 C, the ca- pacity still exhibited as high as 319 mAh/g. The results indicated that the synthesized N-doped coaxial CNTs@α-Fe_2O_3@C nanofibers exhibited high cvcling and rate oerformance.
基金National Natural Science Foundation Youth Project of China(No.51707093).
文摘In this study, the effect of activated peroxydisulfate(PDS) by dielectric barrier discharge(DBD) plasma and activated carbon(HGAC) on the removal of acid orange Ⅱ(AOⅡ) was investigated. The effects of applied voltage, PDS dosage, HGAC dosage, initial pH value, and inorganic anions on the removal rate of AOⅡ were discussed. The main free radicals degrading azo dyes during the experiment were also studied. Experimental results show that the removal rate of AOⅡ in DBD/HGAC/PDS synergistic system is much higher than that in the single system. With the applied voltage of 16 kV, HGAC dosage of 1 g l-1, PDS and AOⅡ molar ratio of 200:1, initial pH value of 5.4 and concentration of AOⅡ solution of 20 mg l-1, the removal rate of AOⅡ reached 97.6% in DBD/HGAC/PDS process after 28 min of reaction.Acidic and neutral conditions are beneficial for AOⅡ removal. Sulfate and hydroxyl radicals play an important role in the removal of AOⅡ. Inorganic anions are not conducive to the removal of AOⅡ.
基金Supported by the National Natural Science Foundation of China(61801027)。
文摘In order to improve the circuit complexity and reduce the long latency of B-1 operations,a novel B-1 operation in Galois Field GF(24)is presented and the corresponding systolic realization based on multiple-valued logic(MVL)is proposed.The systolic structure employs multiplevalued current mode(MVCM)by using dynamic source-coupled logic(SCL)to reduce the initial delay and the transistor and wire counts.The performance is evaluated by HSPICE simulation in 0.18μm CMOS technology and a comparison is conducted between our proposed implementation and those reported in the literature.The initial delay and the sum of transistors and wires in our MVL design are about 43%and 13%lower,respectively,in comparison with other corresponding binary CMOS implementations.The systolic architecture proposed is simple,regular,and modular,well suited for very large scale integration(VLSI)implementations.The combination of MVCM circuits and relevant algorithms based on MVL seems to be a potential solution for high performance arithmetic operations in GF(2k).
基金supported by the National Natural Science Foundation of China(21304044,51663019,and 22062017)the Natural Science Foundation of Inner Mongolia Autonomous Region(2015MS0520,2019JQ03 and 2019BS02004)+2 种基金the State Key Laboratory of Medicinal Chemical Biology(201603006 and 2018051)the State Key Laboratory of Polymer Physics and Chemistry(2018-08)the Program of Higher-Level Talents of Inner Mongolia University(30105-125136)。
文摘Antibiotic-resistant bacteria contamination in environments imposes great threats to human life health.This research aims to develop novel targeted antibacterial biochars for achieving high selectivity to kill pathogenic Escherichia coli(E.coli).The glycopolymer N-halamine-modified biochars(i.e.,BCPMA-Cl)were synthesized by the modification of biochars with poly[2-(methacrylamido)glucopyranose-coacrylamide](P(MAG-co-AM),followed by chlorination treatment.Based on the results of FTIR,turbidity,XPS,and UV–vis,BCPMA-Cl was successfully synthesized and demonstrated to be able to eliminate Staphylococcus aureus(S.aureus)and E.coli.Especially,BCPMA-Cl possessed extremely potent to specific-killing 10^(4) CFU·ml^(-1) of E.coli with lower hemolytic activity(<5%).Additionally,the antibacterial mechanisms of BCPMA-Cl against bacteria were contact-killing and release-killing contributed by active chlorine(i.e.,Cl^(+)).Therefore,this work provided a cost-effective and facile approach for preparation of functional biochars used for bacteria-specific therapeutic applications via livestock pollutants as well as showing a promising strategy to avoid bacterial resistance.
基金Supported by the National Natural Science Foundation of China(61401025)
文摘A polysilicon separated CMOS Schottky barrier diode is designed and tested in this study.By replacing the shallow trench isolation(STI)of a ploy ring,the series resistances of Schottky diodes are reduced,leading to an improvement in cut-off frequencies.The device structure is detailed and a device model is developed.Our analysis on the device shows that the cut-off frequency increases with the decreasing of the Schottky contact area.Based on this observation,the Schottky contact area is set to0.38×0.38μm^2,which is the minimum contact diffusion area allowed by the process flow.The distance between the anode and the cathode is also discussed.Diodes with different dimensions are fabricated and measured.Through extensive measurements,the optimum dimensions are obtained.Bondpads with a reduced area are used to improve the measurement accuracy.The measurement results show that these diodes can achieve a cut-off frequency of 1.5 THz.Thus,it is possible to use these diodes in THz detection.
基金Supported by the National Natural Science Foundation of China(61801024)。
文摘The concept of difference and sum co-array(DSCA)has become a new design idea for planar sparse arrays.Inspired by the shifting invariance property of DSCA,a specific configuration named here as the improved L-shaped array is proposed.Compared to other traditional 2D sparse array configurations such as 2D nested arrays and hourglass arrays,the proposed configuration has larger central consecutive ranges in its DSCA,thus increasing the DOF.At the same time,the mutual coupling effect is also reduced due to the enlarged spacing between the adjacent sensors.Simulations further demonstrate the superiority of the proposed arrays in terms of detection performance and estimation accuracy.
基金National Natural Science Foundation of China(61801027)。
文摘A new AB^2 operation in Galois Field GF(24)is presented and its systolic realization based on multiple-valued logic(MVL)is proposed.The systolic structure of the operation employs multiple-valued current mode(MVCM)by using dynamic source-coupled logic(SCL)to reduce the transistor and wire counts,and the initial delay.The performance is evaluated by HSPICE simulation with 0.18.μm CMOS technology.A comparison is conducted between our proposed implementation and those reported in the literature.The transistor counts,the wire counts and the initial delay in our MVL design show savings of about 23%,45%,and 72%,in comparison with the corresponding binary CMOS implementation.The systolic architecture proposed is simple,regular,and modular,well suited for very large scale integration(VLSI)implementation.The combination of MVCM circuits and relevant algorithms based on MVL seems to be a potential solution for high performance arithmetic operations in GF(2^k).
文摘In recent years,the fast-charging capability of the batteries is highly required,especially used for electric vehicles[1-4].Thus,the commercialized lithium-ion batteries(LIBs)which can be rapidly charged and stably cycled have a huge market prospect[5-7].However,the Li+transmission rate inside the electrode material/interface is sluggish in fast-charge condition,which usually leads to battery impedance increase,Li metal deposition,and electrolyte decomposition.
基金supported by project of China Geological Survey (Grant No.DD20230262,DD20221653,DD20221674,DD20190725,and DD20190561)the Science and Technology Innovation Fund of the Oil and Gas Survey (Grant No.[2023]-YC03).
文摘Over the last 10 years,the China Geological Survey has deployed 137 slim-hole shale gas geological exploration wells for coring entire wellbores.These wells are primarily located in new blocks and geological formations where neighboring well data are insufficient,beyond the scope of developed oil fields in China,or outside of oil and gas company mining-right areas.The drilling rig equipment,coring tools,and core drill bits of slim-hole shale gas drilling technology are different from those associated with traditional petroleum drilling.Many studies have been conducted on non-coring slim-hole drilling technology.This paper focuses on coring technology and drilling safety,summarizing a set of high-efficiency shale gas drilling equipment and technology systems based on geological drilling equipment and techniques(that can be used for solid mineral exploration).We report on:1)an improved vertical shaft drilling rig adapted to shale gas well control safety;2)high-efficiency core drilling techniques,focusing on coring tools,and techniques incorporating an inverted tower drilling tool combination,air circulation follow-through technology,and expanded casing technology;3)research progress on high-efficiency core drill bits,including non-planar tooth polycrystalline diamond compact bits and impregnated diamond core bits,along with their application effects.This research provides substantial advances in drill-core technology and improvements in exploration efficiency.Moreover,it provides a reference frame for well structural design and selection of construction technology for shale gas exploration drilling projects.
基金Supported by a Grant from the National Basic Research Program of China (973 Program)(No.2006CB504508)
文摘OBJECTIVE: To explore the long-term effects and pain relief mechanism of acupotomy by observing changes in nitric oxide synthase (NOS) and beta-en- dorphin (~3-EP) in the hypothalamus, spinal cord, and peripheral blood of rats with third lumbar ver- tebrae (L3) transverse process syndrome. METHODS: Twenty-eight SD rats were randomly as- signed to normal, model, electroacupuncture (EA), and acupotomy group. The last three groups were put through an operation to emulate L3 transverse process syndrome. Fourteen days after the simulation operation, EA and acupotomy treatments were applied to the respective groups. Fifty-six days afterthe simulation operation, biochemistry tests and enzyme-linked immunosorbent assay were used to measure NOS and 13-EP in the hypothalamus, spinal cord, and peripheral blood. RESULTS: Rats with the simulation operation showed significantly higher levels of NOS and II3-EP in the hypothalamus, spinal cord, and peripheral blood than those in the normal group. The EA and acupotomy groups had significantly lower levels of NOS and β-EP than those in the model group. There was no statistical difference between the EA and acupotomy groups. CONCLUSION: EA and acupotomy treatments significantly lowered NOS and β-EP levels in the hypothalamus, spinal cord, and peripheral blood and alleviated L3 transverse process syndrome.
文摘Background Overseas imported dengue fever is an important factor in local outbreaks of this disease in the mainland of China.To better prevent and control such local outbreaks,the epidemiological characteristics and temporal-spatial distribution of overseas imported dengue fever cases in provincial-level administrative divisions(PLADs)where dengue fever is outbreak in the mainland of China were explored.Methods Using the Chinese National Notifiable Infectious Disease Reporting Information System(CNNDS),we identified overseas imported dengue fever cases in dengue fever outbreak areas in the mainland of China from 2005 to 2019 to draw the epidemic curve and population characteristic distribution of overseas imported cases in each PLAD.Based on spatial autocorrelation analysis of ArcGIS 10.5 and temporal-spatial scanning analysis of SaTScan 9.5,we analyzed the temporal-spatial distribution of overseas imported dengue fever in dengue fever outbreak areas in the mainland of China.Results A total of 11,407 imported cases,mainly from Southeast Asia,were recorded from 2005 to 2019 in these 13 PLADs.Of which 62.1%were imported into Yunnan and Guangdong Provinces.Among the imported cases,there were more males than females,mainly from the 21–50 age group.The hot spots were concentrated in parts of Yunnan,Guangdong and Fujian Provinces.We found the cluster of infected areas were expanding northward.Conclusions Based on the analysis of overseas imported dengue cases in 13 PLADs of the mainland of China from 2005 to 2019,we obtained the epidemiological characteristics and spatial distribution of imported dengue cases.Border controls need to pay attention to key population sectors,such as 21–50 years old men and education of key populations on dengue prevention.There is a need to improve the awareness of the prevention and control of imported cases in border areas.At the same time,northern regions cannot relax their vigilance.
基金financially supported by the Beijing National Laboratory for Molecular Sciencesthe Hebei Province Introduction of Foreign Intelligence Projects(2018)the National Natural Science Foundation of China(No.21676070)。
文摘The rich porous structure,high surface area and surface doping make nitrogen doping mesoporous carbon materials(N-MPC)attractive in various areas,including adsorption separation,electrochemical energy storage,catalysis and other fields.Herein,polyvinylpyrrolidone(PVP)is introduced into the polymerization process of assembly of phenol/formaldehyde(PF)resin by means of hydrogen bonds and electrostatic interaction,which not only leads to the formation of uniform mesopores,but also leads to the increase of specific surface area and nitrogen doping.The amount of PVP and annealing temperature has no obvious effect on morphology,but subsequently has effect on the specific surface area and pore volume.When appropriate PVP dosage and annealing temperature are adopted,the obtained N-MPC shows abundant mesoporous,high surface area and suitable nitrogen doping.As electrode materials in supercapacitor,the N-MPC shows good performance with high capacitance good stability and rate performance,presenting its excellent promising in energy storage.
文摘The support elderly parents receive from their grown-up children and the care they provide for grandchildren reflect the intergenerational relationships in Chinese families.Using data on only-child families in urban China from a 2015 survey conducted by the Institute of Population and Labor Economics,Chinese Academy of Social Sciences,this paper studies the status of care provided for grandchildren by parents of first-generation only-child in urban China and considers the effects this support has on the elderly.The data shows that over 80%of only-children parents have cared for their grandchildren.Most only-children also provide support for their elderly parents.Care for grandchildren provided by grandparents increases the economic and housekeeping support for the elderly provided by only-children.Only-children are the main beneficiaries of the intergenerational support that comes from the care for grandchildren provided by elderly parents.If the elderly parents have adequate retirement income and have little or no need for financial support,such intergenerational support resembles“altruism”.However,if the elderly parents do not have adequate retirement income,the satisfaction of their needs depends on resources like time and money available to their only-children.
文摘This paper studies the status of empty nest only-child families in urban China,using data about these families taken from a 2015 survey conducted by the Institute of Population and Labor Economics,Chinese Academy of Social Sciences.Factors that determine the timing of empty nest periods and their duration for only-child parents are also analyzed.The data shows that more than half of the only-child parents surveyed in 2015 lived in empty nests.Some of these parents had been empty-nesters for as many as 25 years.During the life cycle of families,the empty nest status of elderly only-child parents shows different characteristics at different stages,as the only-children begin attending universities,start to work,get married,and have children of their own.There are empty nest periods in only-child families when the only-child leaves the parents for several years and periods when the child returns home and lives with parents for years.The living arrangements of only-child parents depend mainly on changes in the life needs of their only-children.Intergenerational support is focused on meeting the needs of only-children.