Power electronic devices are of great importance in modern society.After decades of development,Si power devices have approached their material limits with only incremental improvements and large conversion losses.As ...Power electronic devices are of great importance in modern society.After decades of development,Si power devices have approached their material limits with only incremental improvements and large conversion losses.As the demand for electronic components with high efficiency dramatically increasing,new materials are needed for power device fabrication.Betaphase gallium oxide,an ultra-wide bandgap semiconductor,has been considered as a promising candidate,and variousβ-Ga_(2)O_(3)power devices with high breakdown voltages have been demonstrated.However,the realization of enhancement-mode(E-mode)β-Ga_(2)O_(3)field-effect transistors(FETs)is still challenging,which is a critical problem for a myriad of power electronic applications.Recently,researchers have made some progress on E-modeβ-Ga_(2)O_(3)FETs via various methods,and several novel structures have been fabricated.This article gives a review of the material growth,devices and properties of these E-modeβ-Ga_(2)O_(3)FETs.The key challenges and future directions in E-modeβ-Ga_(2)O_(3)FETs are also discussed.展开更多
BACKGROUND 99mTc-3PRGD2.SPECT/CT is a commonly used examination method in nuclear medicine.However,patients receiving 99mTc-3PRGD2.SPECT/CT have insufficient knowledge of this method and worry about the examination re...BACKGROUND 99mTc-3PRGD2.SPECT/CT is a commonly used examination method in nuclear medicine.However,patients receiving 99mTc-3PRGD2.SPECT/CT have insufficient knowledge of this method and worry about the examination results.AIM To investigate the effect of teach-back health education combined with structured psychological nursing on adverse emotion and cooperation in patients undergoing 99mTc-3PRGD2.SPECT/CT examination.METHODS Ninety patients undergoing 99mTc-3PRGD2.SPECT/CT examinations were divided into a study group and a control group using a simple random number table,and 45 cases were allocated to each group.Routine nursing was provided to the control group,and teach-back health education combined with structured psychological nursing was provided to the study group on the basis of the control group.Heart rate,diastolic blood pressure,systolic blood pressure,self-rating depression scale(SDS),and self-rating anxiety scale(SAS)were assessed before and after the intervention,and examination cooperation and intervention satisfaction were assessed in the two groups before,during,and after the examination.RESULTS Before the examination,heart rate,diastolic blood pressure,and systolic blood pressure in the study group were not significantly different from the values of the control group(P>0.05).The results of the study group before and after the examination were lower than those in the control group(P<0.05).Before the intervention,SDS and SAS scores in the study group were not significantly different from those in the control group(P>0.05).After the intervention,SDS and SAS scores in the study group were lower than those in the control group(P<0.05).The degree of cooperation was higher in the study group than in the control group(P<0.05).The satisfaction rate with the intervention was higher in the study group than in the control group(P<0.05).CONCLUSION Teach-back health education combined with structured psychological nursing can help maintain the stability of blood pressure and heart rate,relieve negative emotions,and improve the satisfaction and cooperation of patients undergoing 99mTc-3PRGD2.SPECT/CT examinations.展开更多
The degradation of formaldehyde gas was studied using UV/TiO2/O3 process under the condition of continuous flow mode. The effects of humidity, initial formaldehyde concentration, residence time and ozone adding amount...The degradation of formaldehyde gas was studied using UV/TiO2/O3 process under the condition of continuous flow mode. The effects of humidity, initial formaldehyde concentration, residence time and ozone adding amount on degradation of formaldehyde gas were investigated. The experimental results indicated that the combination of ozonation with photocatalytic oxidation on the degradation of formaldehyde showed a synergetic action, e.g,, it could considerably increase decomposing of formaldehyde. The degradation efficiency of formaldehyde was between 73.6% and 79.4% while the initial concentration in the range of 1.84--24 mg/m^3 by O3/TiO2flJV process. The optimal humidity was about 50% in UV/TiO2/O3 processs and degradation of formaldehyde increases from 39.0% to 94.1% when the ozone content increased from 0 to 141 mg/m^3. Furthermore, the kinetics of formaldehyde degradation reaction could be described by Langmuir-Hinshelwood model. The rate constant k of 46.72 mg/（m^3.min） and Langmuir adsorption coefficient K of 0.0268 m^3/mg were obtained.展开更多
The properties of C-H vibration softening for CH2 and CHa radicals absorbed on Cun（n=1-6） clusters have been investigated, using the density functional theory with hybrid functional. The results indicate that the ab...The properties of C-H vibration softening for CH2 and CHa radicals absorbed on Cun（n=1-6） clusters have been investigated, using the density functional theory with hybrid functional. The results indicate that the absorption of CH2 on Cu clusters is stronger than the case of CH3. The vibrational frequencies of C-H bonding agree with the experimental results obtained for CH2 and CH3 absorbed on Cu（111）. With the increase of cluster size, the softening （Einstein shift） of C-H vibrational modes become stronger.展开更多
We consider the quantum mechanical SU（2） transformation e^2λJzJ±e^-2λJz = e^±2λJ±as if the meaning of squeezing with e^±2λ being squeezing parameter. By studying SU（2） operators （J±,...We consider the quantum mechanical SU（2） transformation e^2λJzJ±e^-2λJz = e^±2λJ±as if the meaning of squeezing with e^±2λ being squeezing parameter. By studying SU（2） operators （J±, Jz） from the point of view of squeezing we find that （J±,Jz） can also be realized in terms of 3-mode bosonic operators. Employing this realization, we find the natural representation （the eigenvectors of J＋ or J-） of the 3-mode squeezing operator e^2λJz. The idea of considering quantum SU（2） transformation as if squeezing is liable for us to obtain the new bosonic operator realization of SU（2） and new squeezing operators.展开更多
基金supported in part by the National Basic Research Program of China(Grant No.2021YFB3600202)Key Laboratory Construction Project of Nanchang(Grant No.2020-NCZDSY-008)the Suzhou Science and Technology Foundation(Grant No.SYG202027)。
文摘Power electronic devices are of great importance in modern society.After decades of development,Si power devices have approached their material limits with only incremental improvements and large conversion losses.As the demand for electronic components with high efficiency dramatically increasing,new materials are needed for power device fabrication.Betaphase gallium oxide,an ultra-wide bandgap semiconductor,has been considered as a promising candidate,and variousβ-Ga_(2)O_(3)power devices with high breakdown voltages have been demonstrated.However,the realization of enhancement-mode(E-mode)β-Ga_(2)O_(3)field-effect transistors(FETs)is still challenging,which is a critical problem for a myriad of power electronic applications.Recently,researchers have made some progress on E-modeβ-Ga_(2)O_(3)FETs via various methods,and several novel structures have been fabricated.This article gives a review of the material growth,devices and properties of these E-modeβ-Ga_(2)O_(3)FETs.The key challenges and future directions in E-modeβ-Ga_(2)O_(3)FETs are also discussed.
文摘BACKGROUND 99mTc-3PRGD2.SPECT/CT is a commonly used examination method in nuclear medicine.However,patients receiving 99mTc-3PRGD2.SPECT/CT have insufficient knowledge of this method and worry about the examination results.AIM To investigate the effect of teach-back health education combined with structured psychological nursing on adverse emotion and cooperation in patients undergoing 99mTc-3PRGD2.SPECT/CT examination.METHODS Ninety patients undergoing 99mTc-3PRGD2.SPECT/CT examinations were divided into a study group and a control group using a simple random number table,and 45 cases were allocated to each group.Routine nursing was provided to the control group,and teach-back health education combined with structured psychological nursing was provided to the study group on the basis of the control group.Heart rate,diastolic blood pressure,systolic blood pressure,self-rating depression scale(SDS),and self-rating anxiety scale(SAS)were assessed before and after the intervention,and examination cooperation and intervention satisfaction were assessed in the two groups before,during,and after the examination.RESULTS Before the examination,heart rate,diastolic blood pressure,and systolic blood pressure in the study group were not significantly different from the values of the control group(P>0.05).The results of the study group before and after the examination were lower than those in the control group(P<0.05).Before the intervention,SDS and SAS scores in the study group were not significantly different from those in the control group(P>0.05).After the intervention,SDS and SAS scores in the study group were lower than those in the control group(P<0.05).The degree of cooperation was higher in the study group than in the control group(P<0.05).The satisfaction rate with the intervention was higher in the study group than in the control group(P<0.05).CONCLUSION Teach-back health education combined with structured psychological nursing can help maintain the stability of blood pressure and heart rate,relieve negative emotions,and improve the satisfaction and cooperation of patients undergoing 99mTc-3PRGD2.SPECT/CT examinations.
基金Project supported by the Science Project of Harbin City(No. H2001-12)the Youth Foundation of School of Municipal and Environmental Engineering in Harbin Institute of Technology(No. 01306914).
文摘The degradation of formaldehyde gas was studied using UV/TiO2/O3 process under the condition of continuous flow mode. The effects of humidity, initial formaldehyde concentration, residence time and ozone adding amount on degradation of formaldehyde gas were investigated. The experimental results indicated that the combination of ozonation with photocatalytic oxidation on the degradation of formaldehyde showed a synergetic action, e.g,, it could considerably increase decomposing of formaldehyde. The degradation efficiency of formaldehyde was between 73.6% and 79.4% while the initial concentration in the range of 1.84--24 mg/m^3 by O3/TiO2flJV process. The optimal humidity was about 50% in UV/TiO2/O3 processs and degradation of formaldehyde increases from 39.0% to 94.1% when the ozone content increased from 0 to 141 mg/m^3. Furthermore, the kinetics of formaldehyde degradation reaction could be described by Langmuir-Hinshelwood model. The rate constant k of 46.72 mg/（m^3.min） and Langmuir adsorption coefficient K of 0.0268 m^3/mg were obtained.
文摘The properties of C-H vibration softening for CH2 and CHa radicals absorbed on Cun（n=1-6） clusters have been investigated, using the density functional theory with hybrid functional. The results indicate that the absorption of CH2 on Cu clusters is stronger than the case of CH3. The vibrational frequencies of C-H bonding agree with the experimental results obtained for CH2 and CH3 absorbed on Cu（111）. With the increase of cluster size, the softening （Einstein shift） of C-H vibrational modes become stronger.
基金supported by the National Natural Science Foundation of China(Grant Nos.11175113 and 11275123)the Key Project of Natural Science Fund of Anhui Province,China(Grant No.KJ2013A261)
文摘We consider the quantum mechanical SU（2） transformation e^2λJzJ±e^-2λJz = e^±2λJ±as if the meaning of squeezing with e^±2λ being squeezing parameter. By studying SU（2） operators （J±, Jz） from the point of view of squeezing we find that （J±,Jz） can also be realized in terms of 3-mode bosonic operators. Employing this realization, we find the natural representation （the eigenvectors of J＋ or J-） of the 3-mode squeezing operator e^2λJz. The idea of considering quantum SU（2） transformation as if squeezing is liable for us to obtain the new bosonic operator realization of SU（2） and new squeezing operators.
