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Aqueous amino acid salts are considered as an attractive alternative to alkanolamine solvents (e.g., MEA) for carbon dioxide (CO2) absorption. The kinetics of CO2 into unloaded aqueous solutions of potassium lysinate (LysK) was studied using a wetted wall column at concentrations ranging from 0.25 to 2.0 M and temperatures from 298 to 333 K. Physicochemical properties of aqueous LysK solutions such as density, viscosity, and physical solubility of CO2 were measured to evaluate the reaction rate constants. The reaction pathway is described using zwitterion mechanism taking into account the effect of ionic strength on the reaction rate. Under the fast pseudo-first-order regime, the reaction rate parameters were obtained and correlated in a power-law reaction rate expression. LysK shows higher chemical reactivity toward CO2 than the industrial standard MEA and most of amino acid salts. Its reaction rate constants increase considerably with concentration and temperature. The reaction order is found to be an average value of 1.58 with respect to LysK. The forward second-order kinetic rate constant, k2 0 , are obtained as 31615 and 84822 m3 kmol−1 s−1 at 298 and 313 K, respectively with activation energy of 51.0 kJ mol−1. The contribution of water to the zwitterion deprotonation seems to be more significant than that of LysK for the above-mentioned kinetic conditions

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The influence of inorganic filler TiO2 nanoparticles on the morphology and properties of polysulfone (PS) ultrafiltration membranes was investigated. PS/TiO2 composite membranes were prepared by a phase‐inversion method. TiO2 nanoparticles modified by sodium dodecyl sulfate were uniformly dispersed in an 18 wt % PS casting solution. The addition of TiO2 resulted in an increase in the pore density and porosity of the membrane skin layer. The pore size distribution changed from the log‐normal distribution to the bimodal distribution because of the presence of TiO2 nanoparticles, and some large pores were observed when the concentration of the filler was over 3 wt %. The skin layer was gradually thickened; meanwhile, the morphology sublayer changed from macrovoids to spongelike pores, in comparison with PS membranes without the filler. The addition of TiO2 also induced increases in the hydrophilicity, mechanical strength, and thermal stability. The ultrafiltration experiments showed when the concentration of TiO2 was less than 2 wt %, the permeability and rejection of the membrane was enhanced and then decreased drastically with a higher filler concentration (>3%). © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 879–887, 2006

The controllable oxidation of spiro‐OMeTAD and improving the stability of hole‐transport materials (HTMs) layer are crucial for good performance and stability of perovskite solar cells (PSCs). Herein, we report an efficient hybrid polyoxometalate@metal–organic framework (POM@MOF) material, [Cu2(BTC)4/3(H2O)2]6[H3PMo12O40]2 or POM@Cu‐BTC, for the oxidation of spiro‐OMeTAD with Li‐TFSI and TBP. When POM@Cu‐BTC is introduced to the HTM layer as a dopant, the PSCs achieve a superior fill factor of 0.80 and enhanced power conversion efficiency 21.44 %, as well as improved long‐term stability in an ambient atmosphere without encapsulation. The enhanced performance is attributed to the oxidation activity of POM anions and solid‐state nanoparticles. Therefore, this research presents a facile way by using hybrid porous materials to accelerate oxidation of spiro‐OMeTAD, further improving the efficiency and stability of PSCs.

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The in vivo implanted biomaterials are known to induce inflammatory response and recruit immune cells, which could be used as robust adjuvants for immunotherapy. However, the degree of inflammatory response induced by the implanted biomaterials is hard to control. In this work, we reported the application of three kinds of thermogels from the polypeptide methoxy poly(ethylene glycol)−polyalanine (mPEG− PAla) with various chiralities to regulate the levels of inflammatory responses in vivo. The mPEG−PLAla (EG 45 LA 28 ) and mPEG−PDAal (EG 45 DA 27 ) thermogels exhibited comparable storage modulus (G′) and loss modulus (G″), both of which were about two times higher than the values of the racemic mPEG−PAla (EG 45 RA) thermogel. The component D-alanine in the polypeptide thermogels led to controlled tissue inflammation after subcutaneous injection, and the content of D-alanine could adjust the level of inflammation. The expression of tumor necrosis factor (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) in subcutaneous tissue around the injected thermogel EG 45 DA 27 were 3.62, 1.52, and 4.55 times the levels of those after EG 45 RA thermogel injection and 4. 52, 7.38, and 7.96 times the levels of those after EG 45 LA 28 injection, respectively. The results indicated that the chiral polypeptide thermogels could induce a controllable inflammatory response in vivo and exhibit great potential as an efficient adjuvant for immunotherapy.

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