The electrical properties of C_(60)-tetracyanoquinodimethane(TCNQ)thin films fabricated by using an ionized-cluster-beam method in a high vacuum system were investigated.The films were characterized by transmission el...The electrical properties of C_(60)-tetracyanoquinodimethane(TCNQ)thin films fabricated by using an ionized-cluster-beam method in a high vacuum system were investigated.The films were characterized by transmission electron microscopy(TEM)and electronic spectroscopy.The spectroscopic results evidenced the formation of the charge-transfer complex system in C_(60)-TCNQ thin films and the TEM results revealed the microstructure of the films.The film thickness is of about 100nm.The electromotive intensity at the transition point is a few 107 V/m.The possible mechanism of the electrical phenomena of the films is discussed in the paper.展开更多
Bi-Sr-Ca-Cu-O superconducting fibers have been successfully prepared by means of the laser-heated pedestal growth method.The superconductivity of the fiber sample is closely related to the composition of source materi...Bi-Sr-Ca-Cu-O superconducting fibers have been successfully prepared by means of the laser-heated pedestal growth method.The superconductivity of the fiber sample is closely related to the composition of source material,the power of focused laser beams,the pull rate of growing fiber,and the condition of post-annealing.The typical size of samples is 150μm×30mm.The onset of transition was 118K,and zero resistance was 85K.The majority phase in the fibers is the 85K(2-2-1-2)phase of the Bi-Sr-Ca-Cu-O materials.Samples are stable and reproduceable.展开更多
Surface self-diffusion measurements of tungsten atoms and other defects were carried out by means of field emission fluctuation method at various positions along the zones(011)-(112)and(011)-(001).The experimental res...Surface self-diffusion measurements of tungsten atoms and other defects were carried out by means of field emission fluctuation method at various positions along the zones(011)-(112)and(011)-(001).The experimental results shod that the self-diffusion on stepped surface can be used to investigate thermal roughening procedures.展开更多
Almost all the atoms in the hyperfine sublevel F=4,m_(F)=0("clock level")of cesium ground state have been pumped out by using a laser diode tuned on the Cs-D2 line;and 15.2%population difference(|δoo|)which...Almost all the atoms in the hyperfine sublevel F=4,m_(F)=0("clock level")of cesium ground state have been pumped out by using a laser diode tuned on the Cs-D2 line;and 15.2%population difference(|δoo|)which is more than two times better than what the traditional magnetical selecting state method could provide is found.This experimental result can be applied into building an optically pumped Cs beam frequency standard and better performance will be expected.展开更多
For solving the map-coloring problems,this paper presents an energy function,amore effective dynamic equation and a more simple convergence condition.For the first time westudy the map-coloring problems in the way of ...For solving the map-coloring problems,this paper presents an energy function,amore effective dynamic equation and a more simple convergence condition.For the first time westudy the map-coloring problems in the way of connecting discrete Hopfield neural network withthe orthogonal optimization,and as a practical example,a color map of China is given.展开更多
X-ray diffraction and dielectric studies were performed on synthesized ceramic samples of the section(1-x)(0.8PbMg_(1/3)Nb_(2/3)O_(3)·0.2BiScO_(3))・x(0.8PbTiO_(3)-PbMg_(1/3)Nb_(2/3)O_(3))with x=0-1 of the temary ...X-ray diffraction and dielectric studies were performed on synthesized ceramic samples of the section(1-x)(0.8PbMg_(1/3)Nb_(2/3)O_(3)·0.2BiScO_(3))・x(0.8PbTiO_(3)-PbMg_(1/3)Nb_(2/3)O_(3))with x=0-1 of the temary BiScO_(3)-PbTiO_(3)-PbMg_(1/3)Nb_(2/3)O_(3)(BS-PT-PMN)system,including the temperature dependence of thermally stimulated depolarization currents(TSDC).It was found that the samples are solid solutions with a perovskite structure,which have cubic symmetry in the range of x=0-0.587 and tetragonal symmetry in the range of x=0.680-1.In the intermediate composition range of x-0.587-0.680(morphotropic region-MR),the samples consist of a mixture of solid solutions of different symmetries.Data on the change in dielectric properties and TSDC(T)dependencies of solid solutions with a change in their composition were obtained.It was found that samples of compositions x=0-0.625 and 0.6875-1 exhibit relaxor-ferroelectric and conventional ferroelectric properties,respectively,while samples of compositions x=0.625-0.6875combine ferroelectric and relaxor-ferroelectric properties.展开更多
Ⅰ. INTRODUCTION In recent years, using of the pulse Fourier transform NMR spectrometer for measuring the nuclear magnetic resonance spin-lattice relaxation time （T1） has become an important method for the analyses ...Ⅰ. INTRODUCTION In recent years, using of the pulse Fourier transform NMR spectrometer for measuring the nuclear magnetic resonance spin-lattice relaxation time （T1） has become an important method for the analyses of molecular constructions and the study of molecular dynamics. We have carried out several experiments on this subject. In this paper, we will discuss some problems concerning the techniques for measuring the spin-lattice relaxation time （T1） and the nuclear Overhauser enhancement factor （NOE） of 13C nuclei, and a few ways of eliminating errors.展开更多
Ⅰ. ANALYSIS ON REALIZATION OF HIGH EFFICIENCY CONVERSION The information conversion from infrared to visible has already been discussed by some authors. The detection of weak infrared information will be more fascina...Ⅰ. ANALYSIS ON REALIZATION OF HIGH EFFICIENCY CONVERSION The information conversion from infrared to visible has already been discussed by some authors. The detection of weak infrared information will be more fascinating, if the up-conversion efficiency could be raised to a gain more than one展开更多
In the transmission of two-tone images, one-dimensional run-length coding (ODRLC) is one of the most commonly used approaches. T. S. Huang and others have found that the compression ratio of ODRLC can be improved by c...In the transmission of two-tone images, one-dimensional run-length coding (ODRLC) is one of the most commonly used approaches. T. S. Huang and others have found that the compression ratio of ODRLC can be improved by coding the black run-length (BRL) and the white run-length (WRL) separately. But展开更多
There are two basic kinds of photoemissive materials for the laser pulse detection.One is the photoemissive thin films containing alkali elements,such as Ag-O-Cs,Cs<sub>3</sub>Sb,[Cs]Na<sub>2</sub...There are two basic kinds of photoemissive materials for the laser pulse detection.One is the photoemissive thin films containing alkali elements,such as Ag-O-Cs,Cs<sub>3</sub>Sb,[Cs]Na<sub>2</sub>KSb.F.Gex et al.proposed that the Ag-O-Cs photocathode was the onlyphotoemissive material for detecting laser pulse with the duration≤10 ps and wavelength1.06μm.Another is pure metallic thin films,such as Au,Ag and Cu.The sensitivity ofphotocathodes containing alkali elements is higher than that of others,but this kind ofthin film cannot work at temperature higher than 150℃,nor can it be exposed to theatmosphere for the exposure will make it worthless.This causes the trouble for use。展开更多
The possible biohazards of exposure of human beings to electromagnetic fields in public as well as from occupational situation are always of concern; some EM safety guidelines have been worked out and continuously imp...The possible biohazards of exposure of human beings to electromagnetic fields in public as well as from occupational situation are always of concern; some EM safety guidelines have been worked out and continuously improved in many countries for human beings to live and work safely in the EM environment. As biological effects of EM exposure are of complexity and展开更多
A generalized theory of power-nonorthogonal coupled-modes in a lossless multi-waveguide structure is presented. A set of orthogonal eigenmodes in a multi-wave-guide structure with constant parameters is formed by comb...A generalized theory of power-nonorthogonal coupled-modes in a lossless multi-waveguide structure is presented. A set of orthogonal eigenmodes in a multi-wave-guide structure with constant parameters is formed by combining the nonorthogonal modes. In the waveguide structure with slowly varying parameters, however, the local modes formed by the same combination are still coupled. Finally, an example of two-waveguide coupler is given.展开更多
基金Supported in part by the Doctoral Programme Foundation of Higher Education Commission of Chinathe National Natural Science Foundation of Cliina.
文摘The electrical properties of C_(60)-tetracyanoquinodimethane(TCNQ)thin films fabricated by using an ionized-cluster-beam method in a high vacuum system were investigated.The films were characterized by transmission electron microscopy(TEM)and electronic spectroscopy.The spectroscopic results evidenced the formation of the charge-transfer complex system in C_(60)-TCNQ thin films and the TEM results revealed the microstructure of the films.The film thickness is of about 100nm.The electromotive intensity at the transition point is a few 107 V/m.The possible mechanism of the electrical phenomena of the films is discussed in the paper.
文摘Bi-Sr-Ca-Cu-O superconducting fibers have been successfully prepared by means of the laser-heated pedestal growth method.The superconductivity of the fiber sample is closely related to the composition of source material,the power of focused laser beams,the pull rate of growing fiber,and the condition of post-annealing.The typical size of samples is 150μm×30mm.The onset of transition was 118K,and zero resistance was 85K.The majority phase in the fibers is the 85K(2-2-1-2)phase of the Bi-Sr-Ca-Cu-O materials.Samples are stable and reproduceable.
文摘Surface self-diffusion measurements of tungsten atoms and other defects were carried out by means of field emission fluctuation method at various positions along the zones(011)-(112)and(011)-(001).The experimental results shod that the self-diffusion on stepped surface can be used to investigate thermal roughening procedures.
文摘Almost all the atoms in the hyperfine sublevel F=4,m_(F)=0("clock level")of cesium ground state have been pumped out by using a laser diode tuned on the Cs-D2 line;and 15.2%population difference(|δoo|)which is more than two times better than what the traditional magnetical selecting state method could provide is found.This experimental result can be applied into building an optically pumped Cs beam frequency standard and better performance will be expected.
文摘For solving the map-coloring problems,this paper presents an energy function,amore effective dynamic equation and a more simple convergence condition.For the first time westudy the map-coloring problems in the way of connecting discrete Hopfield neural network withthe orthogonal optimization,and as a practical example,a color map of China is given.
基金support of the Ministry of Education and Science of the Russian Federation as part of the state assignment for creating new youth laboratories(project FSFZ-2022-0007)using equipment of the Collective Usage Center RTU MIREA,which received support from the Ministry of Education and Science of the Russian Federation under Agreement No 075-15-2021-689.
文摘X-ray diffraction and dielectric studies were performed on synthesized ceramic samples of the section(1-x)(0.8PbMg_(1/3)Nb_(2/3)O_(3)·0.2BiScO_(3))・x(0.8PbTiO_(3)-PbMg_(1/3)Nb_(2/3)O_(3))with x=0-1 of the temary BiScO_(3)-PbTiO_(3)-PbMg_(1/3)Nb_(2/3)O_(3)(BS-PT-PMN)system,including the temperature dependence of thermally stimulated depolarization currents(TSDC).It was found that the samples are solid solutions with a perovskite structure,which have cubic symmetry in the range of x=0-0.587 and tetragonal symmetry in the range of x=0.680-1.In the intermediate composition range of x-0.587-0.680(morphotropic region-MR),the samples consist of a mixture of solid solutions of different symmetries.Data on the change in dielectric properties and TSDC(T)dependencies of solid solutions with a change in their composition were obtained.It was found that samples of compositions x=0-0.625 and 0.6875-1 exhibit relaxor-ferroelectric and conventional ferroelectric properties,respectively,while samples of compositions x=0.625-0.6875combine ferroelectric and relaxor-ferroelectric properties.
文摘Ⅰ. INTRODUCTION In recent years, using of the pulse Fourier transform NMR spectrometer for measuring the nuclear magnetic resonance spin-lattice relaxation time （T1） has become an important method for the analyses of molecular constructions and the study of molecular dynamics. We have carried out several experiments on this subject. In this paper, we will discuss some problems concerning the techniques for measuring the spin-lattice relaxation time （T1） and the nuclear Overhauser enhancement factor （NOE） of 13C nuclei, and a few ways of eliminating errors.
文摘Ⅰ. ANALYSIS ON REALIZATION OF HIGH EFFICIENCY CONVERSION The information conversion from infrared to visible has already been discussed by some authors. The detection of weak infrared information will be more fascinating, if the up-conversion efficiency could be raised to a gain more than one
文摘In the transmission of two-tone images, one-dimensional run-length coding (ODRLC) is one of the most commonly used approaches. T. S. Huang and others have found that the compression ratio of ODRLC can be improved by coding the black run-length (BRL) and the white run-length (WRL) separately. But
文摘There are two basic kinds of photoemissive materials for the laser pulse detection.One is the photoemissive thin films containing alkali elements,such as Ag-O-Cs,Cs<sub>3</sub>Sb,[Cs]Na<sub>2</sub>KSb.F.Gex et al.proposed that the Ag-O-Cs photocathode was the onlyphotoemissive material for detecting laser pulse with the duration≤10 ps and wavelength1.06μm.Another is pure metallic thin films,such as Au,Ag and Cu.The sensitivity ofphotocathodes containing alkali elements is higher than that of others,but this kind ofthin film cannot work at temperature higher than 150℃,nor can it be exposed to theatmosphere for the exposure will make it worthless.This causes the trouble for use。
文摘The possible biohazards of exposure of human beings to electromagnetic fields in public as well as from occupational situation are always of concern; some EM safety guidelines have been worked out and continuously improved in many countries for human beings to live and work safely in the EM environment. As biological effects of EM exposure are of complexity and
基金Project supported by the Science Foundation of China State Education Commission.
文摘A generalized theory of power-nonorthogonal coupled-modes in a lossless multi-waveguide structure is presented. A set of orthogonal eigenmodes in a multi-wave-guide structure with constant parameters is formed by combining the nonorthogonal modes. In the waveguide structure with slowly varying parameters, however, the local modes formed by the same combination are still coupled. Finally, an example of two-waveguide coupler is given.
