A covering liquid method to intensify self-preservation effect for safety of methane hydrate storage and transportation

In this work,experiments and comprehensive insights into the proposed covering liquid method to intensify self-preservation effect for methane(CH_(4))storage are presented.The CH_(4)hydrate decomposition percentage was 17.6%with the pressure of 0.61 MPa after 12 h at 266.0 K without a covering liquid,which can be reduced to 12.4%,13.8%,13.0%,and 8.3%with the pressure of 0.26 MPa,0.33 MPa,0.51 MPa,and 0.37 MPa by covering with tetrahydrofuran(THF),cyclopentane(CP),cyclohexane,and n-tetradecane,respectively.When the temperature for CH_(4)hydrate decompositionwas 274.2 K,covering with THF,CP,cyclohexane,and n-tetradecane failed to inhibit CH_(4)hydrate decomposition.The results suggested that the covering liquid may form a new solid layer(a hydrate layer or other solidified layer)around the CH_(4)hydrate,which inhibit CH_(4)transfer below the freezing point of water.However,the new solid layer cannot resist the fast transfer of CH_(4)from decomposed CH_(4)hydrate above the freezing point of water.The same phenomenon was also observed in a sodium dodecyl sulfonate(SDS)-dry solution CH_(4)hydrate formation system.Therefore,the covering method can only intensify the self-preservation effect below the freezing point of water,but cannot generate a self-preservation effect.

Fluorescence Spectroscopic Studies on the Interaction Between a New Bismuth（Ⅲ） Schiff Base Complex and Bovine Serum Albumin

In this work, the binding interaction between a new bismuth（HI） Schiff base complex{ [Bi（valen）]C1.2H2O} [H2valen=N,N′bis（2-hydroxy-3-methoxyphenylmethylidene）-2,6-pyridinediamine, C2 IH19N3O4]and bovine serum albumin（BSA） was studied via fluorescence quenching method. The static quenching constant KLBand some thermodynamic parameters（e.g.,△G^θ, △H^θ and △S^θ） of the interaction were estimated. In particular, thebinding site between the complex and BSA was explored by molecular docking. On the basis of the mechanism ofFOrster energy transfer, the binding distance between the bismuth（Ⅲ） Schiff base complex and BSA（Trp.213） as wellas the transfer efficiency was obtained. Furthermore, the effect of the bismuth（Ⅲ） Schiff base complex on the con-formation of BSA was investigated using synchronous fluorescence spectroscopy.

Synthesis and Bioactivity of a Novel Bismuthoxide Schiff-base Complex Derived from Salen-like Ligand and Bismuth（III） Nitrate

In this paper, a novel bismuthoxide Schiff-base complex [Bi9O8（vanen）3（NO3）2（CH3OH）2（H2O）·3NO3· 5.5H2O]（abbreviated as Bivanen） was synthesized with Salen-like ligand Hzvanen[Hzvanen=N,N＇-ethylene bis（3-methoxysalicylideneimine）] and bismuth（III） nitrate. Its structure was characterized by IR spectra, NMR spectra and X-ray diffraction. In particular, the biology activities of the ligand and the complex against Schizosaecharomyees pombe（S, pombe） were studied using biological mierocalorimetry. The metabolic thermogenic curves of S. pombe were measured at 32.00 ℃. Then, some quantitative thermokinetic parameters of growth metabolism of S. pombe including the rate constant（k）, inhibition ratio（I） and half inhibition concentration（IC50） were calculated. Experimental results showed that the k values of S. pombe decreased while I values of S. pombe increased with the increase of concentrations of the ligand and the complex. The IC50 of the ligand and the complex were found to be 0.067 and 0.037 mmol/L, respectively.