On the P-wave contributions to the cross sections of tt and t̃t̃ near threshold

The approach used for the determination of S-wave amplitudes containing the application of the non-relativistic approximation in the case of P-waves leads to unphysical divergencies. We show how to avoid the latter in calculations of contributions to the cross section near threshold in agreement with field theory. This enables us to give quantitatively reliable predictions for the forward-backward asymmetry and for the axial contribution to the total cross section for the top-antitop system. Also the cross section for the production of stop-antistop near threshold is determined.     

Decouple a coupled KdV system of Nutku and Og̃uz

A coupled KdV system with a free parameter proposed by Nutku and Og̃uz is considered. It is shown that the system passes the WTC's Painlevé test for arbitrary value of the parameter. A further analysis yields that the parameter can be removed and the system can be decoupled.     

High-resolution laser spectroscopy of CaNH2: Analysis of the C̃2A1-X̃2A1 system

Laser excitation spectra of the $\text{C}\text{?}{}^2\text{A}{}_1\text{-}\text{X}\text{?}{}^2\text{A}{}_1$ system of CaNH₂ are reported. Due to the spectral density, individual lines could only be resolved and measured using a filtered fluorescence excitation technique, with a monochromator acting as an optical bandpass filter; 140 line positions were measured in this way and assigned to the parallel K_?1 = 1 subband of what is believed to be the vibrational 0-0 band. The molecular constants were determined from a weighted nonlinear least-squares fit of the line positions.

     

6.

Reasoning out the empirical rule d̃ < 2     

《Physics letters. A》1986,115(5):207-212

     

7.

The B̃2Σ−g (Πu) ← X̃2A1 system of nitrogen dioxide in neon matrices     

H.D. Bist  J.C.D. Brand  A.R. Hoy  V.T. Jones  R.J. Pirkle 《Journal of Molecular Spectroscopy》1977,66(3):411-420

The $\text{B}\text{?}\text{←}\text{X}\text{?}$ band system of NO₂, ${}^2\text{Σ}{}^{\mathrm{?}}{}_{\mathrm{g}}\text{(π}{}_{\mathrm{u}}\text{) ←}{}^2\text{A}{}_1$, has been measured in absorption in a neon matrix at 6 K, using ¹⁵NO₂ and N¹⁸O₂ in addition to the normal isotope. The spectrum consists essentially of a single, long progression of bands terminating on successive levels of the bending mode in the upper state. Transitions to odd- and even-v₂′ states occur with a uniform intensity distribution indicating that the rotation of the bent ground state of NO₂ about its near-prolate axis is hindered in the matrix. The observations strongly suggest that the top axis of the molecule coincides with a C₂ axis of neon crystals in the polycrystalline matrix. Relative to the vapor absorption the matrix spectrum is red shifted by about 150 cm^?1, the crystal field parameter V₂ and principal constants of the $\text{B}\text{?}$ state of ¹⁴N¹⁶O₂ in neon being

$\text{T}{}_{010}\text{14 571 cm}{}^{\mathrm{?1}}\text{: x}{}_{22}\text{, ?0.3 cm}{}^{\mathrm{?1}}\text{;}$

$\text{w}{}_2\text{460.2 cm}{}^{\mathrm{?1}}\text{: V}{}_2\text{, 80 cm}{}^{\mathrm{?1}}\text{.}$

     

8.

The vibrational structure of bromocyanoacetylene cation in the X̃2π and Ã2π electronic states studied by emission and laser exci     

《Journal of Electron Spectroscopy and Related Phenomena》1986,41(2):265-274

The vibrational frequencies of bromocyanoacetylene cation in its ground and first excited electronic states have been obtained by recording and analysing the emission and laser excitation spectra of the òπ-X̃²π transition. In the emission experiments the ions are produced rotationally cooled to ca. 10 K by means of a supersonic free jet and in the laser excitation measurements to ca. 100 K by Penning ionisation followed by collisional relaxation. The resulting narrowing of the vibronic bands in the spectra is such that the vibrational frequencies of most of the fundamentals could be inferred to within ± 2 cm⁻¹.     

9.

Simulation of the Ã2Σ+–X̃2Π absorption and emission spectra of the SiCCl radical     

Alexander O. Mitrushchenkov  Vincent Brites 《Molecular physics》2015,113(13-14):1695-1703

     

10.

Doppler-limited dye laser excitation spectroscopy of the 401 band of the Ã1A2-X̃1A1 system of D2CS     

《Journal of Molecular Spectroscopy》1987,126(1):29-31

     

11.

Hyperfine coupling constants of NCO in Ã2Σ+ by sub-Doppler spectroscopy     

《Journal of Molecular Spectroscopy》1986,120(2):414-420

     

12.

The optical double resonance spectrum of the B̃1A1 state of Cl2CS     

《Journal of Molecular Spectroscopy》1986,115(1):74-81

     

13.

Search for SUSY particles γ̃, ṽ, ẽ, W̃ in electron positron annihilation at 44 GeV     

《Physics letters. [Part B]》1987,194(1):167-172

     

14.

High-resolution photoelectron spectrum of the origin band of the X̃+ 2E ← X̃ 1A1 ionising transition of propyne     

U. Jacovella 《Molecular physics》2018,116(23-24):3602-3606

     

15.

An ab initio calculation of the rotation-vibration energies of the X̃2Σ+ state of CCH using the nonrigid bender Hamiltonian     

《Journal of Molecular Spectroscopy》1986,120(1):236-238

     

16.

NMR and Structural and Conformational Features of 2′-Hydroxychalcones and Flavones     

Artur M. S. Silva  Hilário R. Tavares  Ana I. N. R. A. Barros  José A. S. Cavaleiro 《光谱学快报》2013,46(8):1655-1667

New 2′-hydroxychalcone and flavone derivatives have been synthesised. Their [¹H] and [¹³C] NMR spectra were assigned by the application of COSY and HETCOR experiments and allowed the discussion of some structural aspects. It was shown on the basis of NOE experiments some configurational and conformational features of both type of compounds.     

17.

Laser ultrasonic generation and optical detection and processing     

《声学学报：英文版》1992,(3)

History,present situation and importancy of the laser-generatedultrasonic technique arc presented.Basic principles and some experimentalresults of laser ultrasonic generation and optical detection and processing arediscussed.Several problems about applying this technique to NDT are also dis-cussed in this paper.     

18.

Preparation and Luminescent Properties of ZnO Microrods and Microtubes   总被引：4，自引：0，他引：4       下载免费PDF全文

CHENJian-Gang GUOChang-Xin ZHANGLin-Li HUJun-Tao 《中国物理快报》2004,21(7):1366-1369

Hexagonal ZnO microrods and sub-microrods have been prepared through thermal decomposition of an equimolar (0.1 M) aqueous solution of Zn(NO3)2.4H20 and (CH2)6N4 a~t 90~C for different times (10-46h). The microrods were transformed into hollow hexagonal ZnO microtubes when the growth time reached 46 h. The Raman spectra and the photoluminescent (PL) spectra were measured. The PL spectra of microrods consist of two strong narrow near-UV bands at 380 nm and 400 nm assigned to free exciton emission and exciton-exciton collision, respectively.The PL spectrum of ZnO microtubes show only one peak in the near-UV region with peak located at 380nm with FWHM of about 20nm assigned to free exciton emission. When the growth time increased, the peak intensity of near-UV band decreased.     

19.

Research and Development of SWITRIM Code and Its Applications     

DENG Baiquan HUANG Jinhua FENG Kaiming CHEN Zhi 《核工业西南物理研究院年报(英文版)》2005,(1):108-110

The ftrst numerical simulation code package WITRIM has been developed to calculate the tritium inventory distribution and time-evolution in all sub-systems of FEB fusion reactor. The applications during recent six years indicate that it is reasonable and fully admitted by colleagues abroad. Some creative papers with new concept are published. For instance, we first time pointed out a new phenomenon of ＂tritium well depth and tritium well time＂ during the fusion reactor start-up phase. This is somewhat similar to, but quite different from the ＂iodine well depth and iodine well time＂ poisoning problem during restart-up process of a fission reactor. The authors not only proposed but also numerically solved this new phenomenon. The combination of the SWITRIM code package, user＇s guide, and application example are briefly introduced in this article.     

20.

Structure and stability of neutral and cationic AlnO clusters          下载免费PDF全文

杨鹏  葛建华  姜振益 《中国物理》2007,16(4):1014-1019

In this paper various structural possibilities for AlnO neutral and cationic isomers were investigated by using the B3LYP/6-311G（3df） method. Calculations of this paper predicted the existence of a number of previously unknown isomers. The stabilities of the AlnO （n = 2 - 7） clusters with even n are greater than those with odd n, however the stabilities Of cationic ions have the opposite odd-even alternation. The mass spectra observations of Al17O^＋ and Al19O^＋ ions support our theoretical predictions on their stabilities.     

		Main parameters
	$\text{X}\text{?}{}^2\text{A}{}_1$	$\text{C}\text{?}{}^2\text{A}{}_1$
$\text{T}{}_{\mathrm{k?1}}\text{= 1}$	3-	17375.129(5)
B	0.30079(6)	0.30562(6)
C	0.29319(6)	0.29789(8)
$\text{?}{}_{\mathrm{aa}}$	3-	?0.66(4)
$\text{?}{}_{\mathrm{bb}}$	3-	?0.0356(8)
$\text{?}{}_{\mathrm{cc}}$	3-	?0.0453(8)

The B̃2Σ−g (Πu) ← X̃2A1 system of nitrogen dioxide in neon matrices

The $\text{B}\text{?}\text{←}\text{X}\text{?}$ band system of NO₂, ${}^2\text{Σ}{}^{\mathrm{?}}{}_{\mathrm{g}}\text{(π}{}_{\mathrm{u}}\text{) ←}{}^2\text{A}{}_1$, has been measured in absorption in a neon matrix at 6 K, using ¹⁵NO₂ and N¹⁸O₂ in addition to the normal isotope. The spectrum consists essentially of a single, long progression of bands terminating on successive levels of the bending mode in the upper state. Transitions to odd- and even-v₂′ states occur with a uniform intensity distribution indicating that the rotation of the bent ground state of NO₂ about its near-prolate axis is hindered in the matrix. The observations strongly suggest that the top axis of the molecule coincides with a C₂ axis of neon crystals in the polycrystalline matrix. Relative to the vapor absorption the matrix spectrum is red shifted by about 150 cm^?1, the crystal field parameter V₂ and principal constants of the $\text{B}\text{?}$ state of ¹⁴N¹⁶O₂ in neon being

$\text{T}{}_{010}\text{14 571 cm}{}^{\mathrm{?1}}\text{: x}{}_{22}\text{, ?0.3 cm}{}^{\mathrm{?1}}\text{;}$

$\text{w}{}_2\text{460.2 cm}{}^{\mathrm{?1}}\text{: V}{}_2\text{, 80 cm}{}^{\mathrm{?1}}\text{.}$

     

The vibrational structure of bromocyanoacetylene cation in the X̃2π and Ã2π electronic states studied by emission and laser exci

The vibrational frequencies of bromocyanoacetylene cation in its ground and first excited electronic states have been obtained by recording and analysing the emission and laser excitation spectra of the òπ-X̃²π transition. In the emission experiments the ions are produced rotationally cooled to ca. 10 K by means of a supersonic free jet and in the laser excitation measurements to ca. 100 K by Penning ionisation followed by collisional relaxation. The resulting narrowing of the vibronic bands in the spectra is such that the vibrational frequencies of most of the fundamentals could be inferred to within ± 2 cm⁻¹.     

NMR and Structural and Conformational Features of 2′-Hydroxychalcones and Flavones

New 2′-hydroxychalcone and flavone derivatives have been synthesised. Their [¹H] and [¹³C] NMR spectra were assigned by the application of COSY and HETCOR experiments and allowed the discussion of some structural aspects. It was shown on the basis of NOE experiments some configurational and conformational features of both type of compounds.     

Laser ultrasonic generation and optical detection and processing

History,present situation and importancy of the laser-generatedultrasonic technique arc presented.Basic principles and some experimentalresults of laser ultrasonic generation and optical detection and processing arediscussed.Several problems about applying this technique to NDT are also dis-cussed in this paper.     

Preparation and Luminescent Properties of ZnO Microrods and Microtubes

Hexagonal ZnO microrods and sub-microrods have been prepared through thermal decomposition of an equimolar (0.1 M) aqueous solution of Zn(NO3)2.4H20 and (CH2)6N4 a~t 90~C for different times (10-46h). The microrods were transformed into hollow hexagonal ZnO microtubes when the growth time reached 46 h. The Raman spectra and the photoluminescent (PL) spectra were measured. The PL spectra of microrods consist of two strong narrow near-UV bands at 380 nm and 400 nm assigned to free exciton emission and exciton-exciton collision, respectively.The PL spectrum of ZnO microtubes show only one peak in the near-UV region with peak located at 380nm with FWHM of about 20nm assigned to free exciton emission. When the growth time increased, the peak intensity of near-UV band decreased.     

Research and Development of SWITRIM Code and Its Applications

The ftrst numerical simulation code package WITRIM has been developed to calculate the tritium inventory distribution and time-evolution in all sub-systems of FEB fusion reactor. The applications during recent six years indicate that it is reasonable and fully admitted by colleagues abroad. Some creative papers with new concept are published. For instance, we first time pointed out a new phenomenon of ＂tritium well depth and tritium well time＂ during the fusion reactor start-up phase. This is somewhat similar to, but quite different from the ＂iodine well depth and iodine well time＂ poisoning problem during restart-up process of a fission reactor. The authors not only proposed but also numerically solved this new phenomenon. The combination of the SWITRIM code package, user＇s guide, and application example are briefly introduced in this article.     

Structure and stability of neutral and cationic AlnO clusters

In this paper various structural possibilities for AlnO neutral and cationic isomers were investigated by using the B3LYP/6-311G（3df） method. Calculations of this paper predicted the existence of a number of previously unknown isomers. The stabilities of the AlnO （n = 2 - 7） clusters with even n are greater than those with odd n, however the stabilities Of cationic ions have the opposite odd-even alternation. The mass spectra observations of Al17O^＋ and Al19O^＋ ions support our theoretical predictions on their stabilities.