Theoretical calculation for the equations of state and phase transitions of sodium and potassium hydrides

Abstract

The ionic overlap-compression model is used to calculate the equations of state, as well as the equilibrium properties, of sodium and potassium hydrides (NaH and KH). The present results agree with the experimental ones well. The NaC1-to-CsC1 phase transition pressures for both crystals are also determined. The agreement of the theoretical pressures (23.0 GPa for NaH and 4.9 GPa for KH) with the experimental measurements (29.3 GPa and 4 GPa) is rather good. The calculation shows that the effect of the zero-point vibration to the equilibrium properties and the transition pressures should not be ignored.     

Asymmetric Henry reactions of aldehydes with various nitroalkanes catalyzed by copper(II) complexes of novel chiral N‐monoalkyl cyclohexane‐1,2‐diamines

A number of novel chiral diamines 3 , (1R,2R)‐N‐monoalkylcyclohexane‐1,2‐diamines, were designed and synthesized from trans‐cyclohexane‐1,2‐diamine and applied to the catalytic asymmetric Henry reaction of benzaldehyde and nitromethane to provide β‐nitroalcohol in high yield (up to 99%) and good enantiomeric excess (up to 89%). By using ligand (1R,2R)‐N¹‐(4‐methylpentan‐2‐yl)cyclohexane‐1,2‐diamine ( 3g ), the reaction was optimized in terms of the metal ion, temperature, solvent and base. Further experiments indicated that the complex, 3g –Cu(OAc)₂, was an efficient catalyst in the asymmetric Henry reaction between different aldehydes and nitromethane, and the desired products have been obtained with high chemical yields (up to 99%) and high enantiomeric excess (up to 93%). The optimized catalyst promoted the diastereoselective Henry reaction of various aldehyde substrates and nitroalkane, which gave the corresponding anti‐selective adduct with up to 99% yield and 83:17 anti/syn selectivity. Upon scaling up to gram quantities, the β‐nitroalcohol was obtained in good yield (96%) with excellent selectivities (93% ee). The chiral induction mechanism was tentatively explained on the basis of a previously proposed transition‐state model. Copyright © 2014 John Wiley & Sons, Ltd.     

Recent quantitative research of near infrared spectroscopy in traditional Chinese medicine analysis

Traditional Chinese medicines (TCMs) have been used in China to prevent and cure diseases for centuries. Due to the complexity of TCMs, fast and highly efficient techniques are required to develop their quality control. Near infrared spectroscopy (NIRS) has been widely applied in TCM analysis for both nonpolar and polar components. This review describes an overview of experimental conditions (spectra pretreatments and multivariate techniques) investigated in NIRS for TCM components that are related to individual compounds such as lipids, essential oils, phenolics, alkaloids, saponins and carbohydrates. Their potential in the separation of TCMs using relevant applications with a particular focus on quantitative analysis is also demonstrated.     

MOTION EQUATIONS OF MULTILAYERED ELASTIC ELECTROCONDUCTIVE PLATES IN A MAGNETIC FIELD

ＭＯＴＩＯＮＥＱＵＡＴＩＯＮＳＯＦＭＵＬＴＩＬＡＹＥＲＥＤＥＬＡＳＴＩＣＥＬＥＣＴＲＯＣＯＮＤＵＣＴＩＶＥＰＬＡＴＥＳＩＮＡＭＡＧＮＥＴＩＣＦＩＥＬＤＧｏｕＸｉｎｇ－ｈｕａ（苟兴华）（ＳｉｃｈｕａｎＵｎｉｖｅｒｓｉｔｙ,Ｃｈｅｎｇｄｕ）ＺｈａｎｇＦａ...     

Energies,fine structures,and transition rates of the core‐excited states in BeII

The energies and fine structures of some doubly excited resonances of lithiumlike beryllium are calculated using the saddle‐point variational method. A restricted variational method is used to extrapolate a better nonrelativistic energy. Relativistic and mass polarization corrections are included. Oscillator strengths, transition rates, and wavelengths are also calculated. The results are compared with other theoretical and experiment data in the literature. © 2000 John Wiley & Sons, Inc. Int J Quant Chem 76: 656–661, 2000     

d-Allulose Ameliorates Skeletal Muscle Insulin Resistance in High-Fat Diet-Fed Rats

Background: d-Allulose is a rare sugar with antiobesity and antidiabetic activities. However, its direct effect on insulin sensitivity and the underlying mechanism involved are unknown. Objective: This study aimed to investigate the effect of d-allulose on high-fat diet (HFD)-induced insulin resistance using the hyperinsulinemic–euglycemic (HE)-clamp method and intramuscular signaling analysis. Methods: Wistar rats were randomly divided into three dietary groups: chow diet, HFD with 5% cellulose (HFC), and HFD with 5% d-allulose (HFA). After four weeks of feeding, the insulin tolerance test (ITT), intraperitoneal glucose tolerance test (IPGTT), and HE-clamp study were performed. The levels of plasma leptin, adiponectin, and tumor necrosis factor (TNF)-α were measured using the enzyme-linked immunosorbent assay. We analyzed the levels of cell signaling pathway components in the skeletal muscle using Western blotting. Results: d-allulose alleviated the increase in HFD-induced body weight and visceral fat and reduced the area under the curve as per ITT and IPGTT. d-Allulose increased the glucose infusion rate in the two-step HE-clamp test. Consistently, the insulin-induced phosphorylation of serine 307 in the insulin receptor substrate-1 and Akt and expression of glucose transporter 4 (Glut-4) in the muscle were higher in the HFA group than HFC group. Furthermore, d-allulose decreased plasma TNF-α concentration and insulin-induced phosphorylation of stress-activated protein kinase/Jun N-terminal kinase in the muscle and inhibited adiponectin secretion in HFD-fed rats. Conclusions: d-allulose improved HFD-induced insulin resistance in Wistar rats. The reduction of the proinflammatory cytokine production, amelioration of adiponectin secretion, and increase in insulin signaling and Glut-4 expression in the muscle contributed to this effect.     

A donor–acceptor compound composed of a di­nuclear zinc(II) complex of a Robson macro­cycle with 8‐methyl­quino­line

A donor–acceptor compound, di­aqua‐1κO,2κO‐[μ‐11,23‐dimethyl‐3,7,15,19‐tetra­aza­tri­cyclo­[19.3.1.1^9,13]hexacosa‐1(25),2,7,9,11,13(26),14,19,21,23‐decaene‐25,­26‐diolato‐1κ⁴N³,N⁷,O²⁵,O²⁶:­2κ⁴N¹⁵,N¹⁹,O²⁵,O²⁶]­dizinc(II) diperchlorate bis(8‐methyl­quinoline) ethanol disolvate, [Zn₂(C₂₄H₂₆N₄O₂)(H₂O)₂](ClO₄)₂·2C₁₀H₉N·2C₂H₆O, obtained by the reaction of a dinuclear zinc(II) complex of a Robson macrocycle (acceptor) and 8‐methyl­quinoline (donor), lies about an inversion centre and the coordination about the unique Zn atom is a distorted square pyramid. The fifth coordination site is occupied by the water mol­ecule, Zn—O = 2.016 (2) Å, and the average macrocyclic Zn—O and Zn—N distances are 2.059 (6) and 2.059 (3) Å, respectively.     

锌的表面增强喇曼散射效应

本文从莫育俊等人提出的天线共振子模型理论出发,计算了金属锌的SERS增强特性。天线共振子模型预言,在可见光区,锌的增强因子最大为10,而在红外则会达到很大的增强(10⁵以上).同时,我们通过实验分析了金属锌的SERS增强特性,得到了在可见光区锌的增强因子约为230.在考虑化学增强的情况下,理论计算结果同实验基本一致。     

The Angular Distributions of intermediate Mass Fragments Emittsd in 30 MeV/u 40Ar+58,64Ni and 115In Reactions

The angular distributions of intermediate mass fragments with Z=3-19 emitted in 30 MeV/u ⁴⁰Ar+^58,64Ni and ¹¹⁵In reactions over an angular range of 5°—140°have been measured.Exponential distribution function: dσ/dΩ=N·exp(-θ/a) was used tO fit the measured angular distributions.We have extracted the decay factor a that can be connected with the interaction time τ, and the factor N that is related to the intensity of the emission source.The relationships of a(Z) with Z and N(Z) with Z for different reaction systems and different angular ranges have been discussed. The dependence of angular distributions on isospin and the symmetry of reaction system have also been discussed.