Global transposable characteristics in the complete DNA sequence of the yeast

Global transposable characteristics in the complete DNA sequence of the Saccharomyces cevevisiae yeast is determined by using the metric representation and recurrence plot methods. On the basis of the correlation distance of nucleotide strings, 16 chromosome sequences of the yeast, which are divided into 5 groups, display 4 kinds of the fundamental transposable characteristics: a short increasing period, a long increasing quasi-period, a long major value and hardly relevant.

Mechanism Responsible for the Complete Suppression of Karman Vortex in Flows Past a Wavy Square-Section Cylinder

The Karman vortex shedding is totally suppressed in flows past a wavy square-section cylinder at a Reynolds number of 100 and the wave steepness of 0.025. Such a phenomenon is illuminated by the numerical simulations. In the present study, the mechanism responsible for it is mainly attributed to the vertical vorticity. The geometric disturbance on the rear surface leads to the appearance of spanwise flow near the base. The specific vertical vorticity is generated on the rear surface and convecting into the near wake. The wake flow is recirculated with the appearance of the pair of recirculating cells. The interaction between the upper and lower shear layers is weakened by such cells, so that the vortex rolls could not be formed and the near wake flow becomes stable.

The many-particle scattering system He++ on He: Experiment and a complete unified description

Highly differential experimental results of the scattering system He++ on He at 30 keV are presented as well as a complete unified theoretical description where excitation, transfer and ionization are treated simultaneously on an ab initio level. The agreement even for highly differential cross sections is nearly complete although no explicit correlation besides Pauli correlation is included in the calculations.

Photon production in a chemically equilibrating quark-gluon plasma at finite Baryon density: Complete leading order results

We investigate hard photon production of the near-collinear bremsstrahlung and a new process called the inelastic pair annihilation, fully including the LPM effect, in a chemically equilibrating quark-gluon plasma at finite baryon density, and find that the effect of the system evolution on the photon production and large contribution of the bremsstrahlung make the total photon yield of the two processes as a strongly increasing function of the initial quark chemical potential.

Investigation of two-proton emission from excited states of the odd-Z nucleus P-28 by complete-kinematics measurements

An experiment to study exotic two-proton emission from excited levels of the odd-Z nucleus P-28 was performed at the National Laboratory of Heavy Ion Research-Radioactive Ion Beam Line (HIRFL-RIBLL) facility. The projectile P-28 at the energy of 46.5 MeV/u was bombarding a Au-197 target to populate the excited states via Coulomb excitation. Complete-kinematics measurements were realized by the array of silicon strip detectors and the CsI + PIN telescope. Two-proton events were selected and the relativistic-kinematics reconstruction was carried out. The spectrum of relative momentum and opening angle between two protons was deduced from Monte Carlo simulations. Experimental results show that two-proton emission from P-28 excited states less than 17.0 MeV is mainly two-body sequential emission or three-body simultaneous decay in phase space. The present simulations cannot distinguish these two decay modes. No obvious diproton emission was found.

Novel Oligo-9,9 '-spirobifluorenes through ortho-Linkage as Full Hydrocarbon Host for Highly Efficient Phosphorescent OLEDs

4-Bromo-9,9'-spirobifluorene is facilely synthesized, and from this precursor, two ortho-linked oligo-9,9'-spirobifluorenes, 44BSF and 24TSF, are constructed. Devices with 24TSF as the full-hydrocarbon host material and Ir(ppy)(3) or (ppq)(2)Ir(acac) as the triplet emitter show maximum external quantum efficiencies of 12.6 and 10.5% for green and red electrophosphorescence, respectively.

Crystal structure of a noval poly(aryl ether ketone) containing meta-phenyl linkage

Crystal structure of a novel aryl ether ketone polymer poly(aryl ether ketone ether ketone ketone containing meta-phenyl linkage)(PEKEKmK) was determined by means of WAXD and ED. An orthorhombic unit cell is proposed containing two chains with a=0.772 nm, b=0.604 nm and c=2.572 nm. According to the orthorhombic system, the 10 reflections of this polymer were indexed.

Synthesis and crystallization of a novel poly(ether ketone ether ketone ketone) containing meta-phenylene linkage: PEKEKK(T/I)

Poly(ether ketone ether ketone ketone) containing meta-phenylene linkage (PEKEKK(T/I)) was synthesized by electrophilic Friedel-Crafts acylation condensation of 1, 4-diphenoxybenzophenone with terephthaloyl chloride (T) and isophthaloyl chloride (I) with a T/I ratio of 1 and characterized by LR,DSC,TGA and WAXD. PEKEKK(T/I) has two different crystal structures: a conventional Farm I structure, the same as that observed in PEEK and PEK, wich is usually developed from melt crystallization, and a new Form II structure which can be developed from cold crystallization or solvent induced crystallization (by exposing the glassy sample to methylene chloride).

Crystallization behavior of a novel ether ketone polymer containing meta-phenylene linkage: PEKEKK (T/I)

Nonisothermal and isothermal melt crystallization kinetics of a novel aryl ether ketone polymer containing meta-phenylene linkages, PEKEKK (T/I), were studied by differential scanning calorimetry (DSC). The Avrami equation modified by Jeziorny and a new approach by combining the Avrami equation with the Ozawa equation could describe the nonisothermal crystallization. Isothermal crystallization could also be described by the Avrami equation. The activation energies were 187 and 159 kJ/mol for nonisothermal and isothermal crystallization, respectively. Using the Hoffman-Weeks method, the equilibrium melting point T-m(o) was estimated as 353 degrees C. From the spherulitic growth equation proposed by Hoffman and Lauritzen, the nucleation parameter K-g of the isothermal melt crystallization was estimated as 5.49 x 10(5) K-2. The crystallization characteristics of PEKEKK (T/I) were compared with those of all-para PEKEKK. The differences were explained by differences in the chain flexibility of the two polymers.

Isothermal and nonisothermal crystallization of poly(aryl ether ketone ketone) with all-para phenylene linkage

Isothermal and nonisothermal crystallization behavior for PEKK(T) was studied using differential scanning calorimetry (DSC), transmission electron microscopy (TEM), and electron diffraction (ED). In the isothermal crystallization process, the Avrami parameters obtained were n = 2.33-2.69, which shows crystal growth of two-dimensional extensions consistent with our observations by TEM. The lamellar thickness increases with the crystallization temperature of PEKK(T) crystallized isothermally from the melt. However, for the nonisothermal crystallization of PEKK(T), the results from the modified Avrami analysis show two different crystallization processes. Avrami exponents n(1) = 3.61-5.30, obtained from the primary crystallization process, are much bigger than are the secondary n(2) = 2.26-3.04 and confirmed by the observation of the spherulite morphology. PEKK(T) crystallized isothermally from the melt possesses the same crystal structure (Form I) as that from nonisothermal melt crystallization. The results from TEM observation show that the spherulite radius decreases with an increasing cooling rate. (C) 2001 John Wiley & Sons, Inc.

Complete assignment of H-1-NMR resonances of the king cobra neurotoxin CM-11

The king cobra(Ophiophagus hannah) neurotoxin CM-11 is long-chain peptide with 72 amino acid residues. Its complete assignment of H-1-NMR resonances was obtained using various 2D-NMR technologies, including DQF-COSY, clean-TOCSY and NOESY.

SYNTHESIS, CHARACTERIZATION AND CATALYTIC BEHAVIOR OF LA2-XSRXCOO4+/-LAMBDA (X=0-2) IN COMPLETE OXIDATION

A series of mixed oxides La2-xSrxCoO4+/-lambda (x=0-2) with varying x values was synthesized. The crystal structure of this series of mixed oxides was studied by using XRD. The result showed that when x=0.25-1.5 the mixed oxides possessing K2NiF4 structure are formed. The valences of the transition metal Co and the relation between +/-lambda content and x value by using chemical analysis method have been measured, too. The redox property of this series of mixed oxides and different kinds of oxygen species were studied by IR, TPD, TPR, XPS and SEM methods. The catalytic activity in the complete oxidation of CO and CH4 was investigated and the relationships between the activity, composition and structure of the mixed oxides have been elucidated.