Thermal equation of state of goethite (α-FeOOH)

ABSTRACT

The pressure–volume–temperature (P–V–T) equation of state (EoS) of natural goethite (α-FeOOH) has been determined by an X-ray diffraction study using synchrotron radiation. Fitting the volume data to the third-order Birch–Murnaghan EoS yielded an isothermal bulk modulus, B₀ of 85.9(15)?GPa, and a pressure derivative of the bulk modulus, B′, of 12.6(8). The temperature derivative of the bulk modulus, (?B/?T)_P, was –0.022(9)?GPa?K^?1. The thermal expansion coefficient α₀ was determined to be 4.0(5)?×?10^?5?K^?1.     

Investigation of pulsed laser ablation process of Hg_(0.8)Cd_(0.2)Te

The vaporization threshold was measured under the irradiation of 1.064-μm,10-ns pulsed laser.Then we calculated the vaporization temperature based on the conservation law of energy and analyzed the vaporization time based on our established model.These results coincided well with the information from the micrograph of scanning electron microscope(SEM)and the spectra of the plasma.Besides,the laser ablation rate was also computed and discussed theoretically.     

A Study of Electromagnetic Transition of △(1232) Resonance

Point form relativistic dynamics of relativistic quantum mechanics is employed to estimate the photon and electroproduction amplitudes of △(1232) resonance. Results are compared with the non-relativistic work, and the differences between the two frame works are discussed.     

Abnormal Suppression of Vector-Tensor Decays of ψ(2S)

The hadronic decays ψ(2S)→ρα₂ and K^*0K₂^*0+c.c. have been studied in a sample of 3.6×10⁶ ψ(2S) events.Measurements of their branching fractions are presented.Both channels violate the “15% rule” predicted by perturbative QCD compared with the corresponding J/ψ decays.These results serve as new examples of abnormal suppression of ψ(2S) decays into vector-tensor final states that was first observed in ψ(2S)→ωf₂     

Analyticity of solutions of theO(N) nonlinear σ-model

We consider continuous weak solutions of the Euler-Lagrange equation associated with the Euclideand-dimensionalO(N) nonlinear -model. We show for arbitraryN and arbitraryd that such solutions with locally square integrable gradient are real analytic.     

Contents of the following issues of Opticheskiĭ Zhurnal (Journal of Optical Technology)

Chronicle

Contents of the following issues of Opticheskiĭ Zhurnal (Journal of Optical Technology)     

Strong decays ofΨ(4.03) andΨ(4.16) as radial excitations of charmonium

Considering the signals detected at 4.03 and 4.16 GeV as radial excitations of charmonium, we study their relative decay rates intoD \(\bar D\) ,D \(\bar D^* \) ,D ^* \(\bar D\) ,D ^* \(\bar D^* \) . We point out that one can understand these two peaks as ac \(\bar c\) 3S?2D wave state system with a large mixing angle in a Coulomb+linear interquark potential. We also examine the possibility that these two signals are respectively 3S and 4S wave excitations by studying a logarithmic charmonium potential model. We show that both these interpretations lead to drastically different predictions for the Ψ (4.16) decay rates (eitherD \(\bar D^* \) +D ^* \(\bar D\) orD \(\bar D\) mode is strongly suppressed) which would be very instructive to test experimentally.     

Studies of left-handed Z DNA: Characteristics of Raman spectra of d(GpCpGpCpGpC)

Studies of laser Raman spectra of synthesized DNA fragment, d (GpCpGpCpGpC), were performed. The similarities and differences between the characteristic spectra of the oligomer and those of its structural components, 5′-dGMP and 5′-dCMP, were dis cussed. The information obtained on the characteristic Raman spectrum susceptible to B-Z conformation transition of oligomer might be helpful in further investigation of the biology of left-handed DNA.     

Contents of the following issues of Opticheskiĭ Zhurnal (Journal of optical technology)

Chronicle

Contents of the following issues of Opticheskiĭ Zhurnal (Journal of optical technology)     

Absolute Intensities of the 10-µm Bands of (16)O(3)

Two hundred ninety experimental absolute intensities of nu(1) and nu(3) transitions of ozone have been measured, with good accuracy (<2%). They are used to derive the transition-moment parameters for these bands. The agreement between our observed and calculated line intensities is satisfactory. This work shows that the intensities of these two bands are on average 4% smaller than those used in the literature. In addition, 20 intensities of the nu(2) + nu(3) - nu(2) band confirm this value. Also, 42 line intensities of the 2nu(1)-nu(3) band are reported. Copyright 2001 Academic Press.     

Synthesis and Characterization of Terpolymers of poly(L-lactide-glycolide-ε-caprolactone)

Random terpolymers of poly(L-lactide-glycolide-ε-caprolactone) (PLLGC) was prepared by ring-opening polymerization of L-lactide, glycolide and ε-caprolactone monomers initiated with stannous octanoate. Fourier transform infrared spectra, nuclear magnetic resonance and gel permeation chromatography were employed to characterize the obtained PLLGC terpolymers. The effects of polymerization temperature, reaction time, the amount of initiator and the polymerization pressure on the weight average molecular mass and polydispersity index of the PLLGC were investigated. In addition, the water contact angle of the PLLGC was also tested. The characterization of chemical structure showed that the PLLGC was successfully synthesized. For instance, a PLLGC terpolymer with a weight average molecular mass of about 12.435?×?10⁴?Da and a polydispersity index of 1.28 was obtained when the polymerization was conducted with a molar ratio of monomer to initiator ([M]/[I]) of 2000, polymerization temperature of 140?°C, polymerization pressure of 5.0?Pa and reaction time of 24?h. The random incorporation of ε-CL monomer units decreased the wettability of the PLGA copolymers.     

Structure Properties of Light Nuclei(Ⅰ)Structure of Li Isotopes

The structure properties of Li isotopes are investigated in the framework of large-basis shell model.0hω calculation can reproduce the structure of ^6,7Li, but for some states of ^8,9 Li far from β-stability line the effect of(0+2)hω excitation should be taken into account for reproducing the experiment at data.For drip line nuclei,enlarging model space or changing the interaction can not reproduce the exotic properties of nucleus ¹¹Li.The exotic properties of some states of nuclei ^6—8Li are also briefly discussed.     

Parameters of the energy spectrum of semiconductive solid solutions of the tetradic system (AlSb)x(HgTe)1−x

From the analysis of the spectra of photoluminescence and transparency in the temperature interval (2–77) K there are determined in the paper, the gap-width and its temperature coefficient as a function of the composition of the melt of (AlSb)_x(HgTe)_1–x. It is shown that for compositions (0.8 x 1) with a lowering of the temperature, the edge of the fundamental absorption is shifted into the domain of large energies, and for compositions (0.05 , x 0.20) with a lowering of temperature, the edge of the fundamental absorption is shifted into the long-wave domain of the spectrum. The dependence of E_g(x, T) has a nonlinear character.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 4, pp. 67–70, April, 1991.     

Study of vibrational relaxation of O_3 (001)using photoacoustic technique

I.IntroductionStudyofvibrationalkineticsofozonemoleculesintheatmosphericairisimportantowingtostronginfluenceofthereagent'svibrationalexcitationonratesofchemicalreactionwithparticipationofozone,aproblemreferredtodestructionoftheozonelayerintheatmosphere[1].Majorityofexperimentaldataonvibrationalrelaxationconstantsofozonemoleculeswasobtainedbythelaserfluorescence[2landdoubleresonancel3]techniques.Thesetechniquesallowustomeasuretherateconstantsoflevelpopulationvariationoccurringalloverthepossible…     

Observation of the Molecular Quenching of μp(2S) Atoms

Kinetic energy distributions of muonic hydrogen atoms μp(1S) have been obtained by means of a time-of-flight technique for hydrogen gas pressures between 4 and 64 hPa. A high energy component of ∼900 eV observed in the data is interpreted as the signature of long-lived μp(2S) atoms, which are quenched in a non-radiative process leading to the observed high energy: the collision of a thermalized μp(2S) atom with a hydrogen molecule H₂ results in the resonant formation of a {[(ppμ)⁺]^*pee}^* molecule. Then the (ppμ)⁺ complex undergoes Coulomb de-excitation and the ∼1.9 keV excitation energy is shared between a μp(1S) atom and one proton. The preliminary analysis of the time spectra gives a long-lived μp(2S) population of ∼1% of all stopped muons, and a quenching rate of ∼4⋅10¹¹ s⁻¹. This revised version was published online in August 2006 with corrections to the Cover Date.     

Spectrophotometric Study of Basicity of Some Substituted α-(Benzamtoomethyl)phenylhydrazines

The protonation behavior at 25°C in water and in aqueous sulfuric acid solutions of some substituted α-(p-R-benzamidomethyl)phenyl hydrazines (R=H, CH₃, Cl, Br) was investigated by UV spectrophotometry. The absorption spectra in sulfuric acid solutions were analyzed by the method of multivariate analysis. The premonition constants of hydrazine (pK₁) and amide (pK₂) moieties were determined; pK₂ values were calculated from the reconstituted absorption spectra by Cox - Yates method. Dependence of pK₂ on Hammett's a constants was discussed.     

Determination of the number of ψ(3686)events at BESⅢ

The numbers of ψ(3686) events accumulated by the BESⅢ detector for the data taken during 2009 and2012 are determined to be(107.0±0.8)×10~6 and(341.1±2.1)×10~6, respectively, by counting inclusive hadronic events,where the uncertainties are systematic and the statistical uncertainties are negligible. The number of events for the sample taken in 2009 is consistent with that of the previous measurement. The total number of ψ(3686) events for the two data taking periods is(448.1±2.9)×10~6.     

Irreducible Representation of Quantum SLq(3) Algebra (Ⅰ)

The explicit forms of the irreducible representation matricea for the quantum SLq(3) enveloping algebra are computed in analogy to the irreducible tensor technique in the classical SU(3) algebra.     

A simulation study of rapid solidification and crystal configuration of Cu_(70)Ni_(30) alloy

1 Introduction It is well known that the performances of metal materials are mainly determined by their special microcosmic configuration formed in the concreting processes. For under- standing the relationship between the configuration and performance, it is very impor- tant both in theory and practice to find out the form and transition feature of microcos- mic configuration by tracking the concreting processes of liquid metals. Cu-Ni alloy is a completely solid solution or a single-phase al…