Hanle lifetime measurements of SrI 1P1 and CaI 1P1 levels excited by a neutral beam of 1 1S0 helium atoms

A 0.8 keV He(1 ¹S₀) beam was used to coherently excite the ¹P₁ levels of Sr and Ca targets. The coherence appears as an alignment of the excited state with respect to the beam axis. We report here the results of a Hanle measurement, or a zero-field level-crossing experiment, performed on these coherently excited levels. The radiative lifetimes of the SrI ¹P₁ and CaI ¹P₁ levels were measured to be 4.7 ns and 5.3 ns, respectively. These values are in good agreement with conventional Hanle measurements.     

1H NMR Studies of 1-Ethylimidazole Binding to Cytochrome C

Abstract

Kinetic and equilibrium data for 1-EtIm binding to cyt c at temperature range of 303–319K have been determined at pH 7.0 by using ¹HNMR method. Thermodynamic values (ΔH°=39.5 kJ mol^?1, ΔS° = 154 J mol^?1K^?1 and Ea = 142 kJ mol^?1) are obtained from Van't Hoff and Arrhenius's relations. Some hyperfine shifted resonances of l-EtIm cyt c have been assigned for the first time using 1D saturation transfer experiments. The origin of the asymmetric spin density distribution in heme groups of 1-EtIm cyt c and the reason of low affinity of cytochrome c for 1-EtIm are also discussed move toward upfield from original position. However, Te-2, 4 substituents in cyt c are more electron withdrawing than the propionic acid side chains, which lead to the 5-methyl group going toward downfield.     

1 states and the 1f-2p shell model

The observed 1⁺ cross sections from (³He, p) reactions on even Ca, Ti, Cr and Fe targets are analyzed in terms of an approximate sum rule. It is shown that the summed 1⁺ cross sections in a qualitative way depend on the proton and neutron number of the target as predicted from the shell model.     

The A 1Σ+ → X 1Σ+ bands of the isotopic lithium hydrides

In order to obtain a better understanding of the X¹Σ⁺ ground state and the A¹Σ⁺ state potential energy curves of lithium hydride and to examine in detail the concept of “mass-reduced quantum numbers” for both an ordinary (X¹Σ⁺) and an anomalous (A¹Σ⁺) electronic state, the emission spectra of the A¹Σ⁺ → X¹Σ⁺ bands of the isotopic lithium hydrides and deuterides were photographed in the 3000–5000-Å region with a 3.4-m Ebert Spectrograph. The bands found involved v″ = 0 to 7 to various v′ = 0 to 17 for ⁶LiH, and v″ = 0 to 7 to various v′ = 1 to 16 for ⁶LiD. Additional bands involving v″ = 4 and 5 were also found for ⁷LiH. The vibrational-rotational spectroscopic analysis of ⁷LiH, ⁶LiH, and ⁶LiD are reported here, as are the reanalyses of the ⁷LiH and ⁷LiD data reported by Crawford and Jorgensen. New Rydberg-Klein-Rees (RKR) A¹Σ⁺ and X¹Σ⁺ potential curves have been constructed for each individual molecule and are reported, but detailed isotopic comparisons will be reported in subsequent publications.     

Five-nucleon spectroscopic amplitudes for 1p-shell nuclei

Spectroscopic amplitudes of the ⁵He or ⁵Li cluster in the ground and first excited states are given for lp-shell nuclei. These Spectroscopic amplitudes are calculated with the aid of intermediate-coupling wave functions of initial and final nuclei. Sum rules for pickup and stripping reactions are presented. The selectivity in excitation of the final states in pickup and stripping reactions of the ⁵He or ⁵Li cluster for some targets are discussed.     

Spectroscopic parameters and molecular constants of HI(X~1Σ~+),DI(X~1Σ~+) and TI(X~1Σ~+) isotope molecules

The potential energy curve (PEC) of HI(X¹Σ⁺) molecule is studied using the complete active space self-consistent field method followed by the highly accurate valence internally contracted multireference configuration interaction approach at the correlation-consistent basis sets, aug-cc-pV6Z for H and aug-cc-pV5Z-pp for I atom. Using the PEC of HI(X¹Σ⁺), the spectroscopic parameters of three isotopes, HI(X¹Σ⁺), DI(X¹Σ⁺) and TI(X¹Σ⁺), are determined in the present work. For the HI(X¹Σ⁺), the values of D₀, D_e, R_e, ω_e, ω_eχ_e, α_e and B_e are 3.1551 eV, 3.2958 eV, 0.16183 nm, 2290.60 cm^-1, 40.0703 cm^-1, 0.1699 cm^-1 and 6.4373 cm^-1, respectively; for the DI (X¹Σ⁺), the values of D₀, D_e, R_e, ω_e, ω_eχ_e, α_e and B_e are 3.1965 eV, 3.2967 eV, 0.16183 nm, 1626.8 cm^-1, 20.8581 cm^-1, 0.0611 cm^-1 and 3.2468 cm^-1, respectively; for the TI (X¹Σ⁺), the values of D₀, D_e, R_e, ω_e, ω_eχ_e, α_e and B_e are of 3.2144 eV, 3.2967 eV, 0.16183 nm, 1334.43 cm^-1, 14.0765 cm^-1, 0.0338 cm^-1 and 2.1850 cm^-1, respectively. These results accord well with the available experimental results. With the PEC of HI(X¹Σ⁺) molecule obtained at present, a total of 19 vibrational states are predicted for the HI, 26 for the DI, and 32 for the TI, when the rotational quantum number J is equal to zero (J = 0). For each vibrational state, vibrational level G(?), inertial rotation constant B_? and centrifugal distortion constant D_? are determined when J = 0 for the first time, which are in excellent agreement with the experimental results.     

JF1/B6F1 Ngly1−/− mouse as an isogenic animal model of NGLY1 deficiency

N-Glycanase 1 (NGLY1) deficiency is a congenital disorder caused by mutations in the NGLY1 gene. Because systemic Ngly1^−/− mice with a C57BL/6 (B6) background are embryonically lethal, studies on the mechanism of NGLY1 deficiency using mice have been problematic. In this study, B6-Ngly1^−/+ mice were crossed with Japanese wild mice-originated Japanese fancy mouse 1 (JF1) mice to produce viable F₂ Ngly1^−/− mice from (JF1×B6)F₁ Ngly1^−/+ mice. Systemic Ngly1^−/− mice with a JF1 mouse background were also embryonically lethal. Hybrid F1 Ngly1^−/− (JF1/B6F1) mice, however, showed developmental delay and motor dysfunction, similar to that in human patients. JF1/B6F1 Ngly1^−/− mice showed increased levels of plasma and urinary aspartylglycosamine, a potential biomarker for NGLY1 deficiency. JF1/B6F1 Ngly1^−/− mice are a useful isogenic animal model for the preclinical testing of therapeutic options and understanding the precise pathogenic mechanisms responsible for NGLY1 deficiency.     

Some perturbation calculations for 1s2p, 1s 22p,and 1s 22s

The Dalgarno interchange theorem is used, together with the U function approach, to evaluate the first order perturbation corrections to <r ₁ ^-1+r ₂ ^-1> and <r ₁ + r ₂> for the two-electron states 1s2p ¹ P and 1s2p ³ P. The results for <r ₁ + r ₂> are extended by using a screening approximation, and are compared with the results of accurate variational calculations. The first order perturbation correction to spin-weighted expectation values of type <ΣV(r_j )s_zj > is given for the three-electron states 1s ²2p ² P and 1s ²2s ² S. The case V(r_j ) = r _j ^-1 is treated in detail.     

Density functional study of hypophosphite adsorption on Ni (1 1 1) and Cu (1 1 1) surfaces

Surface structures and electronic properties of hypophosphite, H₂PO₂⁻, molecularly adsorbed on Ni(1 1 1) and Cu(1 1 1) surfaces are investigated in this work by density functional theory at B3LYP/6-31++g(d, p) level. We employ a four-metal-atom cluster as the simplified model for the surface and have fully optimized the geometry and orientation of H₂PO₂⁻ on the metal cluster. Six stable orientations have been discovered on both Ni (1 1 1) and Cu (1 1 1) surfaces. The most stable orientation of H₂PO₂⁻ was found to have its two oxygen atoms interact the surface with two PO bonds pointing downward. Results of the Mulliken population analysis showed that the back donation from 3d orbitals of the transition metal substrate to the unfilled 3d orbital of the phosphorus atom in H₂PO₂⁻ and 4s orbital's acceptance of electron donation from one lone pair of the oxygen atom in H₂PO₂⁻ play very important roles in the H₂PO₂⁻ adsorption on the transition metals. The averaged electron configuration of Ni in Ni₄ cluster is 4s^0.634p^0.023d^9.35 and that of Cu in Cu₄ cluster is 4s^1.004p^0.033d^9.97. Because of this subtle difference of electron configuration, the adsorption energy is larger on the Ni surface than on the Cu surface. The amount of charge transfers due to above two donations is larger from H₂PO₂⁻ to the Ni surface than to the Cu surface, leading to a more positively charged P atom in Ni_nH₂PO₂⁻ than in Cu_nH₂PO₂⁻. These results indicate that the phosphorus atom in Ni_nH₂PO₂⁻ complex is easier to be attacked by a nucleophile such as OH⁻ and subsequent oxidation of H₂PO₂⁻ can take place more favorably on Ni substrate than on Cu substrate.     

Classical CP N−1 crystal

Two-dimensional Euclidean CP ^N?1 ffields are conformal-transformed into fields with periodic spatial (crystal-like) structures, both at zero temperature and at finite temperature. Specific solutions of the crystal-like CP ^N?1 model are discussed     

2p-1h states in 17N

States populated in the ¹⁵N(t,p)¹⁷N reaction at 15 MeV are compared with those in the ¹⁶O(t,p)¹⁸O reaction at the same energy. On the basis of this comparison several spins and parities are assigned. Cross-section ratios are in rough agreement with a weak-coupling model.     

N1−3H configurations in 4He

Wavefunctions for N¹?³H configurations in ⁴He are calculated using NN → N¹N transition potentials V and ³HN → N¹³H transition potentials from a two-nucleon exchange mechanism. The radial N¹?³H momentum distributions peak at ～ fm^?1 which is much lower than the short-ranged V. For (πN) S-wave isobars, e.g. N¹(1535) and N¹(1700), N¹?³H probabilities are estimated to be ～2‰ each, while those for N¹'s in higher (πN) partial waves are much smaller.     

Causality in 1+1-dimensional Yukawa model-II

The limits g → large, M → large with (g ³/M) ?=? const. of the 1+1-dimensional Yukawa model are discussed. The conclusion of the results on bound states of the Yukawa model in this limit (obtained in arXiv:0908.4510v3 [hep-th]) is taken into account. It is found that model reduces to an effective non-local ? ³ theory in this limit. Causality violation also is observed in this limit.     

Lifetimes of the levels 31P, 41P and 51P in Li II by the beam-foil technique

Radiative lifetimes of the Li II levels 3¹P, 4¹P and 5¹P are extracted from the observed vacuum-UV-transitions 3¹P → 2¹S, 4¹P → 2¹S, and 5¹P → 2¹S, respectively. The measured values agree well with theory.     

Self-Alignment of 1P1-Levels of Alkaline-Earth Elements in a Hollow Cathode Discharge

The self-alignment of some ¹P¹- level of alkaline-earth elements in a hollow cathode discharge is investigated. The radiative lifetimes and the signal broadening constants are determined from the Hanle signals.     

Levelcrossing experiments in the first excited1 P 1 states of the alkaline earths

The hyperfine structure of the lowest¹P₁ state of²⁵Mg,⁴³Ca,⁸⁷Sr,¹³⁵Ba and¹³⁷Ba have been measured by the level-crossing and anticrossing technique. The magnetic dipole and electric quadrupole coupling constants determined by these measurements are²⁵Mg(3s3p¹P₁):A=? 7.7(5) MHz; 16 MHz>B>0 MHz,⁴³Ca(4s4p¹P₁):A=? 15.3(4) MHz; ¦B¦<12 MHz,⁸⁷Sr (5s5p¹P₁:A=? 3.4(4) MHz;B=39(4) MHz,¹³⁵Ba(6s6p¹P₁):A=? 97.5(1.0) MHz;B=31(9)MHz,¹³⁷Ba(6s6p¹P₁):A=?109.2(1.2) MHz;B=51(12)MHz. The results have been compared with the predictions of the Breit-Wills theory of the two-electron hyperfine structure using the experimental data on the³P states. Large discrepancies have been observed which are due to different radial wave functions of thes andp electron in the triplet and singlet system. This effect has been taken into account by fitting the data with the aid of two additional parameters. That this procedure is justified is shown by an analysis of the fine structure splitting, the life times, and the isotopic shifts in thesp configurations of group II elements.     

High-lyingM 1-states of spherical nuclei

The cross section of inelastic scattering of slow electrons at large angles with excitation of high-lying 1⁺-states in²⁰⁸Pb are calculated in DWBA. The calculations are carried out both in the random-phase approximation and with the interaction of one-and two-phonon states in the framework of semi-microscopic quasi-particle-phonon model. A group of noncollective 1⁺-states with a large excitation probability in backward (e, é)-scattering is found in the excitation energy region of 17–21 MeV. We discuss also the problem of existence, properties, and possibility of discovery the high-lying collective 1⁺-states (2?ω M 1-resonance) predicted by Speth et al.