Lithium‐Salt‐Containing High‐Molecular‐Weight Polystyrene‐block‐Polyethylene Oxide Block Copolymer Films

Ionic conductivity in relation to the morphology of lithium‐doped high‐molecular‐weight polystyrene‐block‐polyethylene oxide (PS‐b‐PEO) diblock copolymer films was investigated as solid‐state membranes for lithium‐ion batteries. The tendency of the polyethylene (PEO) block to crystallize was highly suppressed by increasing both the salt‐doping level and the temperature. The PEO crystallites completely vanished at a salt‐doping ratio of Li/EO>0.08, at which the PEO segments were hindered from entering the crystalline unit of the PEO chain. A kinetically trapped lamella morphology of PS‐b‐PEO was observed, due to PEO crystallization. The increase in the lamella spacing with increasing salt concentration was attributed to the conformation of the PEO chain rather than the volume contribution of the salt or the previously reported increase in the effective interaction parameter. Upon loading the salt, the PEO chains changed from a compact/highly folded conformation to an amorphous/expanded‐like conformation. The ionic conductivity was enhanced by amorphization of PEO and thereby the mobility of the PEO blocks increased upon increasing the salt‐doping level.     

Layer-by-layer fabrication of an anatase titania multilayer with gradual sponge-like morphology

The fabrication of a functional multilayer system with a gradually hierarchical order formed by individual titania thin films of different porosity is investigated. The porous or sponge-like nanostructures are fabricated using a diblock copolymer assisted sol–gel process. The successive spin-coating of the sol–gel solution onto the silicon substrate deposits a thin polymer nanocomposite film which is transformed to purely anatase titania nanostructures via calcination. In total, this procedure is repeated layer by layer for three times. This layer-by-layer approach is monitored with grazing incidence small-angle X-ray scattering (GISAXS) after each fabrication step. The GISAXS investigation is complemented in real space with a scanning electron microscopy characterization of the respective preparation stages. From the characterization, a porous titania multilayer system with gradually structured levels is clearly identified.     

Role of Nickel Nanoparticles in High‐Performance TiO2/Ni/Carbon Nanohybrid Lithium/Sodium‐Ion Battery Anodes

Super‐small sized TiO₂ nanoparticles are in situ co‐composited with carbon and nickel nanoparticles in a facile scalable way, using difunctional methacrylate monomers as solvent and carbon source. Good control over crystallinity, morphology, and dispersion of the nanohybrid is achieved because of the thermosetting nature of the resin polymer. The effects of the nickel nanoparticle on the composition, crystallographic phase, structure, morphology, tap density, specific surface area, and electrochemical performance as both lithium‐ion and sodium‐ion battery anodes are systematically investigated. It is found that the incorporation of the in situ formed nickel nanoparticles with certain content effectively enhances the electrochemical performance including reversible capacities, cyclic stability and rate performance as both lithium‐ion and sodium‐ion battery anodes. The experimental I‐V profiles at different temperatures and theoretical calculations reveal that the charge carriers are accumulated in the amorphous carbon regions, which act as scattering centers to the carriers and lower the carrier mobility for the composite. With increasing nickel content, the mobility of the charge carriers is significantly increased, while the number of the charge carriers maintains almost constant. The nickel nanoparticles provide extra pathways for the accumulated charge, leading to reduced scatterings among the charge carriers and enhanced charge‐carrier transportation.     

Kinetics of Collapse Transition and Cluster Formation in a Thermoresponsive Micellar Solution of P(S‐b‐NIPAM‐b‐S) Induced by a Temperature Jump

Structural changes at the intra‐ as well as intermicellar level were induced by the LCST‐type collapse transition of poly(N‐isopropyl acrylamide) in ABA triblock copolymer micelles in water. The distinct process kinetics was followed in situ and in real‐time using time‐resolved small‐angle neutron scattering (SANS), while a micellar solution of a triblock copolymer, consisting of two short deuterated polystyrene endblocks and a long thermoresponsive poly(N‐isopropyl acrylamide) middle block, was heated rapidly above its cloud point. A very fast collapse together with a multistep aggregation behavior is observed. The findings of the transition occurring at several size and time levels may have implications for the design and application of such thermoresponsive self‐assembled systems.     

Krein's method with certain singular kernel for solving the integral equation of the first kind

In this paper, we are going to obtain the spectral relations for the Fredholm integral equation of the first kind with certain singular kernel, by using Krein's method.     

Synthesis and Pharmacological Activity of Some Novel Macrocyclic Pentapeptidopyridine and 3,5-Bis(tripeptidohydrazone)pyridine Schiff Bases

Russian Journal of General Chemistry - New Schiff bases containing macrocyclic 3,5-pyridine pentapeptide, linear 3,5-bis(tripeptido)pyridine methyl ester and hydrazide moieties have been...     

Time-resolved ultrathin cobalt film growth on a colloidal polymer template

Cobalt (Co) sputter deposition onto a colloidal polymer template is investigated using grazing incidence small-angle X-ray scattering (GISAXS), scanning electron microscopy (SEM), and atomic force microscopy (AFM). SEM and AFM data picture the sample topography, GISAXS the surface and near-surface film structure. A two-phase model is proposed to describe the time evolution of the Co growth. The presence of the colloidal template results in the correlated deposition of an ultrathin Co film on the sample surface and thus in the creation of Co capped polystyrene (PS) colloids. Well below the percolation threshold, the radial growth is restricted and only height growth is observed.     

Androgen receptor antagonists and anti-prostate cancer activities of some synthesized steroidal candidates

In continuation of our previous work, a novel series of steroid derivatives were synthesized and their androgen receptor (AR) antagonist activities and in vivo antiandrogenic properties were evaluated. Twenty-one heterocyclic derivatives containing a cyanopyrane ring fused to a steroidal moiety were conveniently synthesized and screened for their antagonistic, antiandrogen and prostate anticancer activities comparable to that of bicalutamide as the reference control. Some of the compounds exhibited better antagonistic, antiandrogen and prostate anticancer activities than the reference controls. Initially the acute toxicity of the compounds was assayed via the determination of their LD(50). Synthetic steroidal structures fused to a substituted cyanopyrane ring seem to be a promising approach in the search for novel leads for potent antagonistic, antiandrogen and prostate anticancer agents.     

Eco-Friendly UPLC–MS/MS Method for Determination of a Fostamatinib Metabolite,Tamatinib, in Plasma: Pharmacokinetic Application in Rats

Fostamatinib is a prodrug of the active metabolite tamatinib, which is a spleen tyrosine kinase (Syk) inhibitor used in the treatment of primary chronic adult immune thrombocytopenia and rheumatoid arthritis. A highly sensitive, rapid, reliable, and green method was developed and validated using ultra-performance liquid chromatography and tandem mass spectrometry (UPLC–MS/MS) for quantification of tamatinib in rat plasma. Ibrutinib was used as internal standard and liquid–liquid extraction was applied using tert-butyl methyl ether. The analyte was separated on an Acquity^TM CSH C₁₈ (2.1 mm × 100 mm, 1.7 µm) column using mobile phase consisting of 10 mM ammonium acetate and acetonitrile (10:90) and the flow rate was 0.25 mL/min. Electrospray ionization (ESI) was carried out in positive mode. Quantitation of tamatinib and the IS was performed using multiple reaction monitoring mode with precursor-to-product transitions of m/z 471.1 > 122.0 and m/z 441.1 > 84.0, respectively. The calibration range was 0.1–1000.0 ng/mL and the linearity of the method was ≥0.997. The developed method greenness was investigated. All principal parameters for the method, including linearity, accuracy, precision, recovery, and stability, were within acceptable ranges. Tamatinib pharmacokinetic study in rats was successfully carried out using the developed method.