Removal of CO2 from High-Temperature Flue Gas by PDMS/IL composite membranes

Membrane separation of CO2 from high-temperature flue gas has economic benefits. Thus, the development of thermal-stable polymeric membranes with efficient permselectivity is very crucial. In this work, we designed a...

Synthesis of renewable alkylated decalins with p-quinone and 2-methyl-2,4-pentanediol

Decalins are the main component of JP-900, a coal-based thermal stable advanced aviation fuel. Meanwhile, these compounds are also widely used as additives to improve the volumetric heat value and...

Preparation and investigation of Dy3+/Tm3+ doped NaGd(MoO4)2 with thermal-stable and tunable white light emitting for LED applications

In this work, a series of Dy3+-doped, Tm3+-doped and Dy3+/Tm3+-codoped NaGd(MoO4)2 (NGM) were successfully prepared via high-temperature solid-state method. The crystal structure, band structure, elemental composition, and photoluminescence (PL) properties...

The phase transition of polyamide 6 with pre-stretching process at different temperatures

The temperature and strain fields are two key factors in the regulation of fibrous aggregate structure. In this paper, plate specimens of polyamide 6 were prepared by compression molding method. The oriented polyamide 6 plates were systematically analyzed from aspects of mechanical properties, thermal properties, crystal structure and crystal morphology. The maximum tensile strength and elastic modulus of polyamide 6 plate appeared at 120℃. The stretching process induced the formation of a more thermal stable α-form crystals. With the increase of stretching temperature, α-form crystals transformed into γ-form crystals gradually. The crystal chips transformed into fibrils during the stretching process. The structural evolution model of materials under the temperature and strain fields was established.

Organocatalytic Ring-Opening Polymerization of ε-Caprolactone Using bis(N-(N′-butylimidazolium)alkane Dicationic Ionic Liquids as the Metal-Free Catalysts: Polymer Synthesis, Kinetics and DFT Mechanistic Study

In this work, we successfully synthesized high thermal sTable 1,n-bis(N-(N′-butylimidazolium)alkane bishexafluorophosphates (1,n-bis[Bim][PF6], n = 4, 6, 8, and 10) catalysts in 55–70% yields from imidazole which were applied as non-toxic DILs catalysts with 1-butanol as initiator for the bulk ROP of ε-caprolactone (CL) in the varied ratio of CL/nBuOH/1,4-bis[Bim][PF6] from 200/1.0/0.25–4.0 to 700/1.0/0.25–4.0 by mol%. The result found that the optimal ratio of CL/nBuOH/1,4-bis[Bim][PF6] 400/1.0/0.5 mol% at 120 °C for 72 h led to the polymerization conversions higher than 95%, with the molecular weight (Mw) of PCL 20,130 g mol−1 (Đ~1.80). The polymerization rate of CL increased with the decreasing linker chain length of ionic liquids. Moreover, the mechanistic study was investigated by DFT using B3LYP (6–31G(d,p)) as basis set. The most plausible mechanism included the stepwise and coordination insertion in which the alkoxide insertion step is the rate-determining step.

Synthesis, Characterization and Thermal Studies of Fe(II), Co(II), Ni(II) and Cu(II) Complexes with bis-(4-benzylidenamino-phenyl)-methane Schiff base ligand

A new series of Co(II), Fe(II), Cu(II) and Ni(II) complexes of Bis–(4-benzylidenamino-phenyl)-methane (L) have been prepared and characterized. The complexes conform to general formula [CoL(H2O)3] Cl2, [FeL(H2O)5]SO4.2H2O, [CuL(H2O)5] NO3 and [NiL(H2O)3Cl2], Infra red spectra and elemental analysis reveal uni-dentate coordination of Schiff base to metal ions. Molar conductivity measurements show that complexes (I, III) behave as 2:1 electrolyte while complex (II) behave as 1:1 electrolyte. The thermal studies for complexes shows that the complexes are thermal stable.

Spectral studies of bismuth-containing pyrochlores

Thermal stable solid solutions of titanates, niobates, and tantalates of bismuth with a pyrochlore structure doped with 3d-metal atoms were studied using XPS and NEXAFS spectroscopy. Based on spectral studies, it was shown that the manganese, cobalt, nickel and copper atoms in these solid solutions have mainly charge state +2 and iron atoms – charge state +3.

Effect of organic additives on storage stability of camel liver catalase against environmental conditions

The storage stability of catalase is very low under practical reaction conditions. Therefore, this study is aimed to evaluate the storage stability of catalase from camel liver by treated it with polyethylene glycol (PEG), glycerol, bovine serum albumin (BSA) and glucose against different storage conditions. The effect of some additives as stabilizers on the storage stability of camel liver catalase at 4°C and 30°C after 30 and 90 days was studied. The enzyme with additives at 5%concentration was more stable at 4 and 30°C for 90 days of incubation than native enzyme. The activity of catalase was more thermal stable in presence of 5%additive. The activity of enzyme with 5%BSA and glucose was retained 60%of its activity at 60°C. At pH 11 the catalase with glucose retained 30%of its activity. The native enzyme lost 80%of its activity in presence of 5 mM β-mercaptoethanol, where the enzyme with additive retained 30–46%of its activity. At 8 M urea, the native enzyme and enzyme with 5%of all additives retained 28%and 61–77%of its activity, respectively. The catalase with additives retained 50–90%of its activity in presence of different dyes. The results appeared that the catalase with additives may be used for elimination of excess of hydrogen peroxide after bleaching of textile.