Redshift drift exploration for interacting dark energy

By detecting redshift drift in the spectra of Lyman-$\alpha$ forest of distant quasars, Sandage-Loeb (SL) test directly measures the expansion of the universe, covering the "redshift desert" of $2 \lesssim z \lesssim5$. Thus this method is definitely an important supplement to the other geometric measurements and will play a crucial role in cosmological constraints. In this paper, we quantify the ability of SL test signal by a CODEX-like spectrograph for constraining interacting dark energy. Four typical interacting dark energy models are considered: (i) $Q=\gamma H\rho_c$, (ii) $Q=\gamma H\rho_{de}$, (iii) $Q=\gamma H_0\rho_c$, and (iv) $Q=\gamma H_0\rho_{de}$. The results show that for all the considered interacting dark energy models, relative to the current joint SN+BAO+CMB+$H_0$ observations, the constraints on $\Omega_m$ and $H_0$ would be improved by about 60\% and 30--40\%, while the constraints on $w$ and $\gamma$ would be slightly improved, with a 30-yr observation of SL test. We also explore the impact of SL test on future joint geometric observations. In this analysis, we take the model with $Q=\gamma H\rho_c$ as an example, and simulate future SN and BAO data based on the space-based project WFIRST. We find that in the future geometric constraints, the redshift drift observations would help break the geometric degeneracies in a meaningful way, thus the measurement precisions of $\Omega_m$, $H_0$, $w$, and $\gamma$ could be substantially improved using future probes.Comment: 6 pages, 5 figures; accepted for publication in EPJC. arXiv admin note: text overlap with arXiv:1407.712

Comparison Between Single Loading–Unloading Indentation and Continuous Stiffness Indentation

Experiments are performed on fused silica, Si, and duplex stainless steel to examine whether the CSM (continuous stiffness indentation) method will provide approximately the “same” results of contact modulus and indentation hardness as those measured from the quasi-static single loading–unloading indentation. The experimental results show that the elastic modulus measured by the CSM method is compatible with that by the quasi-static loading–unloading method for hard materials, while there exists a percentage difference of ∼21.3% between the smallest value and the largest vale of the measured indentation hardnesses from the CSM method for fused silica and a percentage difference of ∼15.3% between the hardnesses measured by the CSM method and the single indentation for duplex stainless steel. The large percentage difference suggests that the indentation hardness measured by the CSM method may not be compatible with that measured by the quasi-static loading–unloading method for hard materials. The finite element results reveal the percentage difference between the indentation hardness at the wave peak and that at the wave valley for the CSM method increases with the increase of the ratio of elastic modulus to yield stress

An Efficient Process for Pretreatment of Lignocelluloses in Functional Ionic Liquids

Background and Aims. The complex structure of the lignocelluloses is the main obstacle in the conversion of lignocellulosic biomass into valuable products. Ionic liquids provide the opportunities for their efficient pretreatment for biomass. Therefore, in this work, pretreatment of corn stalk was carried out in ultrasonic-assisted ionic liquid including 1-butyl-3-methylimidazolium chloride [BMIM]Cl, 1-H-3-methylimidazolium chloride [HMIM]Cl, and 1-(1-propylsulfonic)-3-imidazolium chloride [HSO3-pMIM]Cl at 70°C for 2 h. We compared the pretreatments by ionic liquid with and without the addition of deionized water. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were employed to analyze the chemical characteristics of regenerated cellulose-rich materials. Results. [HMIM]Cl and [HSO3-pMIM]Cl were effective in lignin extraction to obtain cellulose-rich materials. FTIR analysis and SEM analysis indicated the effective lignin removal and the reduced crystallinity of cellulose-rich materials. Enzymatic hydrolysis of cellulose-rich materials was performed efficiently. High yields of reducing sugar and glucose were obtained when the corn stalk was pretreated by [HMIM]Cl and [HSO3-pMIM]Cl. Conclusions. Ionic liquids provided the ideal environment for lignin extraction and enzymatic hydrolysis of corn stalk and [HMIM]Cl and [HSO3-pMIM]Cl proved the most efficient ionic liquids. This simple and environmentally acceptable method has a great potential for the preparation of bioethanol for industrial production

Bis[1,3-bis­(1-methyl-1H-benzimidazol-2-yl)-2-oxapropane]­cadmium dipicrate acetonitrile sesquisolvate 0.25-hydrate

In the title compound, [Cd(C18H18N4O)2](C6H2N3O7)2·1.5CH3CN·0.25H2O, the CdII ion is coordinated by four N atoms and two O atoms from two tridentate 1,3-bis­(1-methyl-1H-benzimidazol-2-yl)-2-oxopropane ligands in a distorted octa­hedral coordination environment. The lengths of the chemically equivalent Cd—O bonds [2.4850 (16) and 2.5488 (16)Å] are signiificantly different. One of the picrate anions is disordered over two sets of sites, with refined occupancies of 0.504 (15) and 0.496 (15). A 0.5-occupancy acetonitrile solvent mol­ecule is disordered over two sites with equal occupancies. The H atoms of a 0.25-occupancy solvent water mol­ecule were neither located nor included in the refinement

Bis[1,3-bis­(1-ethyl-1H-benzimidazol-2-yl)-2-oxapropane]­cadmium(II) dipicrate dimethyl­formamide disolvate

In the title compound, [Cd(C20H22N4O)2](C6H2N3O7)2·2C3H7NO, the CdII ion is coordinated by four N atoms and two O atoms from two tridentate 1,3-bis­(1-ethyl-1H-benzimid­azol-2-yl)-2-oxapropane ligands in a distorted octa­hedral environment

Bis[N,N-bis­(1-allyl-1H-benzimidazol-2-ylmethyl-κN 3)benzyl­amine-κN]cadmium dipicrate

The crystal structure of the title compound, [Cd(C29H29N5)2](C6H2N3O7)2, consists of CdII complex cations and picrate anions. In the complex cation, the CdII ion is chelated by two bis­(1-allyl­benzimidazol-2-ylmeth­yl)benzyl­amine (babb) ligands in a distorted octa­hedral geometry. Extensive C—H⋯O hydrogen bonding occurs between cations and anions in the crystal structure