- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Purification of the Recombinant Green Fluorescent Protein Using Aqueous Two-Phase System Composed of Recyclable CO2-Based Alkyl Carbamate Ionic Liquid
摘要： The formation of aqueous two-phase system (ATPS) with the environmentally friendly and recyclable ionic liquid has been gaining popularity in the field of protein separation. In this study, the ATPSs comprising N,N-dimethylammonium N′,N′-dimethylcarbamate (DIMCARB) and thermo-responsive poly(propylene) glycol (PPG) were applied for the recovery of recombinant green fluorescent protein (GFP) derived from Escherichia coli. The partition behavior of GFP in the PPG + DIMCARB + water system was investigated systematically by varying the molecular weight of PPG and the total composition of ATPS. Overall, GFP was found to be preferentially partitioned to the hydrophilic DIMCARB-rich phase. An ATPS composed of 42% (w/w) PPG 1000 and 4.4% (w/w) DIMCARB gave the optimum performance in terms of GFP selectivity (1,237) and yield (98.8%). The optimal system was also successfully scaled up by 50 times without compromising the purification performance. The bottom phase containing GFP was subjected to rotary evaporation of DIMCARB. The stability of GFP was not affected by the distillation of DIMCARB, and the DIMCARB was successfully recycled in three successive rounds of GFP purification. The potential of PPG + DIMCARB + water system as a sustainable protein purification tool is promising.
关键词： aqueous two-phase system,purification,recycling,poly(propylene glycol),green fluorescent protein,dialkyl carbamate
更新于2025-09-09 09:28:46
-
Environmentally-friendly technology for rapid on-line recycling of acrylonitrile-butadiene-styrene, polystyrene and polypropylene using near-infrared spectroscopy
摘要： The recovery of waste acrylonitrile-butadiene-styrene (ABS), polystyrene (PS) and polypropylene (PP) from waste white goods was inefficient due to their similar chemical and physical property. In this work, an environmental friendly equipment based on on-line dynamic recognition for recycling the waste white goods plastic stream (i.e. ABS, PS and PP mixture) was established. It included the recognition process utilizing the near infrared (NIR) range 1050nm-1350nm and separation process using the air ejection. In particular, NIR spectrum of waste plastic stream were acquired on-line and analyzed dynamically with the self-designed software. Results showed that although ABS, PS and PP share very similar chemical and physical property, it is possible to separate them with a high accuracy up to 99%. Meanwhile, the optimized operating parameters of the separation process were studied to guide the further industrial recycling process. The study revealed the potentiality of NIR technique as mechanical methods in recycling of plastics from the waste white goods.
关键词： on-line recognition,plastic separation,plastic recycling,NIR spectrum analysis
更新于2025-09-04 15:30:14
-
Recycling of Silicon Sludge and its Optical Properties
摘要： We have developed a mass production process of Si quantum dots using photo-induced chemical etching method with oxidation and etching agents and have investigated its optical properties. Average size of the fabricated Si quantum dots was estimated to be 2 nm. Absorption peaks of the fabricated quantum dots were observed in the short wavelength regions, e.g., 200 - 350 nm. On the other hand, in the case of raw sludge, absorption was not observed in the UV-visible wavelength regions due to the narrow energy band gap (e.g., 1.12 eV). The calculated energy band gap of fabricated Si quantum dots was calculated to be 3.5 eV by the modified Kubelka-Munk function. Blue emission peaks around 475 nm wavelengths were observed due to the quantum confinement effect. When the emission peak was fixed, two excitation peaks were observed in 340 nm and 380 nm, respectively, which seemed to be due to the energy band gap widening and/or surface coating with an ultrathin layer.
关键词： Silicon sludge,Recycling,Photoluminescence,Chemical etching
更新于2025-09-04 15:30:14
-
Near-infrared Zeeman spectroscopy for the spatially resolved measurement of helium emission spectra in Heliotron J
摘要： A passive spectroscopic method that can measure spatially resolved emission spectra only by observing from a single diagnostic port without assuming plasma symmetry was applied to the stellarator-heliotron device Heliotron J. The emission spectra from the inboard and outboard sides were separated using the difference in their Zeeman effects. On the basis of the fact that in a spectrum as a function of the wavelength, the magnitude of the wavelength splitting by the Zeeman effect relative to the Doppler broadening increases with the wavelength, the method was applied to a near-infrared helium emission line (He I 1s2s 3S?1s2p 3P, 1083 nm), and it was confirmed that the uncertainty in the separated spectra was reduced compared with that in the application to visible emission lines. From the emissivity of the separated spectra, the local recycling flux was evaluated using the inverse photon efficiency method.
关键词： Zeeman effect,plasma surface interaction,stellarator,recycling,plasma spectroscopy,tomography
更新于2025-09-04 15:30:14
-
Estudo das propriedades ópticas de vidros borosilicatos dopados com íons de Itérbio em fun??o da concentra??o
摘要： Rare Earth elements have been studied for different scientific areas due to its excellent spectroscopic and magnetic properties with possible application for construction of different optical and electric devices (MARTINS, 2005; LOUREN?O et al., 2011). In this work, it is studied the optical properties of Ytterbium (Yb3+) ions embedded in a lead-borosilicate glass matrix synthesized by the melting method, using the optical absorption and photoluminescence techniques. The Yb3+ ions were chosen to dope the glass matrix because it has an energy level scheme more simplified compared with other Rare-Earth ions, with only two energy levels, making it very attractive for the construction of high efficiency optical devices. Increasing the annealing temperature as well as the ion concentration in the matrix leads to a shift of the optical band gap of the matrix to higher energies. We believe that this shift (blue-shift) can be associated with the nanocrystallization process of the glass matrix SBP (SiO2, B2O3, PbO2). The reduction of radiative lifetime with increasing ion concentration in matrix was studied using the Stokowski empirical relation, in which, it studies processes of energy transfer as a function of Rare-Earth concentration.
关键词： LiCoO2 extraction,Recycling,Process optimization,Lithium-ion batteries
更新于2025-09-04 15:30:14