The trigonometric $$E_8$$ E 8 R-matrix

Letters in Mathematical Physics - An expression for the R-matrix associated with $${\mathcal {U}}_q({\widehat{\mathfrak e_8}})$$ in its 249-dimensional representation is given using the...     

不同初始温度时Na_8 Na_8团簇碰撞动力学研究

采用距离相关紧束缚的分子动力学模型 ,在不同初始温度T0 =0 .0 2K、50K、10 0K、2 0 0K、30 0K、4 0 0K时 ,对Na8 Na8在质心系轰击能量为 0 .0 12 5eV/n的中心碰撞时的反应动力学进行了研究。发现团簇碰撞动力学与初始温度密切相关。在T0 <10 0K时 ,初始温度不影响反应动力学 ,而在T0 =4 0 0K时将对反应动力学有强烈影响。     

Monolithic Uncooled 8 × 8 Bolometer Arrays Based on Poly-SiGe Thermistor

This paper presents a monolithic uncooled 8 × 8 bolometer array with polycrystalline silicon-germanium (poly-SiGe) thermistors as active elements. The poly-SiGe films are deposited by ultrahigh vacuum vapor deposition (UHV/CVD) system and the dependence of the temperature coefficient of resistance (TCR) on annealing temperature has been investigated. To decrease the thermal conductance of the bolometer, the poly-SiGe thermistor was formed on a four leg suspended microbridge. The improved porous silicon micromachining techniques described here enable the integration of the bolometer array with the MOS readout circuitry. The measurements and calculations show that the mean responsivity is 1.07 × 10⁴ V/W with an uncorrected uniformity of 10.5% and a thermal response time of 10.5 ms, and the detectivity of 3.75 × 10⁸ cm Hz^1/2/W is achieved at a chopping frequency of 30 Hz and a bias voltage of 5 V.     

用于高温等离子体实验的C_8H_8簿膜

一、引言 在核聚变、X射线激光和激光等离子体的研究中,对高温等离子体辐射的X射线诊断,是了解等离子体与激光相互作用的最基本的手段之一。对激光等离子体X射线光谱的分析认为,X射线光子能量在1keV附近的产额最高,所带的信息量亦最丰富,因此人们对等离子体的诊断研究大都集中在这一软X射线波段上。而用于该波段的各类探测器所需要的滤     

不同初始温度时Na8+Na8团簇碰撞动力学研究

采用距离相关紧束缚的分子动力学模型,在不同初始温度T0=0.02 K、50 K、100 K、200 K、300 K、400 K时,对Na8+Na8在质心系轰击能量为0.012 5 e V/n的中心碰撞时的反应动力学进行了研究。发现团簇碰撞动力学与初始温度密切相关 。在T0＜100 K时,初始温度不影响反应动力学,而在T0=400 K时将对反应动 力学有强烈影响。     

COMPACTIFICATION FROM E8 × E8 TO THE STANDARD MODEL

The comnactification of the D=10 E₈ × E₈ field theory limit of superstring to the D=4 SU₃ × SU₂ × U₁ standard model is investigated by means of the scheme developed by Manton, Forgacs and Chapline.     

Experiment at SPring-8

The GeV photon beam at SPring-8 is produced by backward-Compton scattering of laser photons from 8 GeV electrons. The maximum energy of the photon will be above 3 GeV, and the beam intensity will be 10⁷ photons/sec. Polarization of the photon beam will be 100 % at the maximum energy with fully polarized laser photons. We report the outline of the quark nuclear physics project with this high-quality high-intensity beam.     

Thermal and Spectrophotometric Analysis of Liquid Crystal 8CB/8OCB Mixtures

The binary system of 4-octyl-4′-cyanobiphenyl (8CB) and 4-octyloxy-4′-cyanobiphenyl (8OCB) has been studied by means of differential scanning calorimetry (DSC) and ultraviolet absorption spectrophotometry (UV). The phase-transition temperatures, enthalpies, and entropies have been determined by using calorimetric methods on DSC. The results indicate clearly the existence of three-phase regions across the crystalline-to-smectic A, smectic A-to-nematic, and nematic-to-isotropic transitions in the 8CB/8OCB mixtures. The obtained phase-transition temperatures of the 8CB/8OCB mixtures are between the data for 8CB and 8OCB. A few of the phase transitions cannot be observed at high heating rates. The phase-transition temperatures of the 8CB/8OCB mixtures rise with the heating rate between 2°C/min and 15°C/min. The activation energies were calculated by the Ozawa method for the phase transitions of 25% 8CB and 75% 8OCB liquid crystal mixtures. UV experiments were carried out to characterize the absorptivity constants of liquid crystal and their mixtures. The molar absorptivity and maximum absorption wavelengths were measured in chloroform solution by UV spectrophotometry. The maximum absorption wavelength of the 8CB/8OCB mixtures increases with decreasing percent weight of 8CB in 8OCB, a result associated with the different lengths of the alkyl chain.     

Thermal stability of cubane C8H8

The reasons for the anomalously high thermal stability of cubane C₈H₈ and the mechanisms of its decomposition are studied by numerically simulating the dynamics of this metastable cluster at T = 1050–2000 K using a tight-binding potential. The decomposition activation energy is found from the temperature dependence of the cubane lifetime obtained from the numerical experiment; this energy is fairly high, E _a = 1.9 ± 0.1 eV. The decomposition products are, as a rule, either C₆H₆ and C₂H₂ molecules or the isomer C₈H₈ with a lower energy. Original Russian Text ? M.M. Maslov, D.A. Lobanov, A.I. Podlivaev, L.A. Openov, 2009, published in Fizika Tverdogo Tela, 2009, Vol. 51, No. 3, pp. 609–612.     

Merrifield-Simmons Index and Its Entropy of the 4-8-8 Lattice

The Merrifield-Simmons index is a topological index used in structural chemistry for quantifying relevant properties of molecular structure. This index, in different names, has been studied on the square, triangular and hexagonal lattices by using the method of transfer matrix. To compute the Merrifield-Simmons index of more complicated lattices such as the 4-8-8 and triangular Kagomé lattices, the use of multi-step transfer matrices is needed. In this paper we introduce the concept of transfer multiplicity and use multi-step transfer matrices to derive a rigorous upper and lower bound for the entropy of Merrified-Simmons index of the 4-8-8 lattice. We show that this method can be used to deal with other complex 2-dimensional lattices.     

Editorial board page for “Spectroscopy Letters”, Volume 8, Number 8

This is a scanned image of the original Editorial Board page(s) for this issue.