Free ions

Ebook "The role of water in ATP hydrolysis energy transduction by protein machinery" introduces recent progress in biological energetics from ATP hydrolysis to molecular machineries. The role of water is now recognized to be essential in biological molecular energetics. Although energetics is a rather distant field to many biologists, any working models for protein machineries such as protein motors, transporters, and other enzymes must be consistent with their energetics.

346p tracanhphuonghoa1007 22-04-2024 7 2   Download

Ebook "Particle induced electron emission I (Springer tracts in modem physics, Volume 122)" discusses collision-induced electron emission from nearly free-electron metals by ion or electron impact. This subject is, as is well known, of acute importance in understanding plasma-wall interactions in thermonuclear reactors. It is also the basis for one of the most exciting technological developments of the last few years - scanning electron miscroscopy.

141p coduathanh1122 27-03-2024 2 1   Download

Ebook "Multiscale and multiphysics computational frameworks for nano- and bio-systems" develops multiscale and multiphysics simulation methods to understand nano- and bio-systems by overcoming the limitations of time- and length-scales. Here the key issue is to extend current computational simulation methods to be useful for providing microscopic understanding of complex experimental systems.

191p manmanthanhla0201 26-02-2024 5 1   Download

Ebook "Applications of EPR in radiation research" presented in eight themes: elementary radiation processes (in situ and low temperature radiolysis, quantum solids); solid state radiation chemistry (crystalline, amorphous and heterogeneous systems); biochemistry, biophysics and biology applications (radicals in biomaterials, spin trapping, free-radical-induced DNA damage); materials science (polymeric and electronic materials, materials for treatment of nuclear waste, irradiated food);...

766p nhanphanguyet 28-01-2024 5 2   Download

The ketalization reaction of glycerol with acetone for solketal formation was performed using a gel-type ion exchange resin, Indion 225H in a solvent-free medium. The experimental parameters molar ratio, catalyst loading, rate of stirring, and temperature were analyzed and evaluated for their impact on the conversion of glycerol. A kinetic model based on the Langmuir–Hinshelwood–Hougen– Watson (LHHW) equation described the kinetics of the heterogeneous system.

11p lyhuyenthu 31-01-2023 10 2   Download

We produced and characterized copper(II)-chitosan complexes fabricated via in-situ precipitation as antibioticfree antibacterial biomaterials. Copper was bound to chitosan from a dilute acetic acid solution of chitosan and copper(II) chloride exploiting the ability of the polysaccharide to chelate metal ions.

9p vihermione 06-01-2023 3 2   Download

Immobilized metal chelate affinity chromatography (IMAC) support was practiced for α-amylase immobilization. Poly(hydroxyethylmethacrylate-methacryloylamidotryptophan)-Ni2+[p(HEMA-MAT)-Ni2+] nanospheres, average diameter 100 nm, were produced by surfactant free emulsion polymerization. Characterizations of p(HEMAMAT)-Ni2+ nanospheres were carried out by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscope (SEM). In addition, average particle size, size distribution, and surface charge were specified.

13p langthannam 29-12-2021 14 1   Download

In this study peripherally tetra-substituted metal-free, metallophthalocyanines bearing (3,4-dimethoxybenzyl) oxy groups have been synthesized and characterized. Electrochemical properties of novel phthalocyanines 4, 5, 6, and 7 were determined by cyclic and square wave voltammetry in order to define their possible applications in different electrochemical technologies. CoII and TiIVO metal ions behave as redox active cations in the core of the CoPc and TiOPc complexes, respectively

12p langthannam 29-12-2021 5 0   Download

Poly(N-isopropylacrylamide-co-allyl acetic acid) [p(NIPAM-co-AAAc)] microgels were synthesized in aqueous medium by free radical emulsion polymerization using N-isopropylacrylamide as monomer, allylacetic acid as comonomer, and N,N-methylene-bis-acrylamide as cross-linker. Silver nanoparticles were fabricated inside the microgels by in situ reduction of silver ions. Microgels were analyzed by UV-visible spectroscopy, FTIR, XRD, TEM, and DLS. The formation of silver nanoparticles was confirmed by UV-visible spectroscopy.

13p langthannam 29-12-2021 8 0   Download

This paper describes the synthesis of a series of metal-free phthalocyanines and metallophthalocyanines peripherally substituted by macrocycles of different ring sizes with the same donor atom sets. The effects of varying ring size of the macrocycle on the spectroscopic and metal ion binding properties of phthalocyanines were examined. For these purposes, electronic absorption properties for metal-free phthalocyanines and metallophthalocyanines were studied in dimethylformamide and tetrahydrofuran.

14p langthannam 29-12-2021 3 0   Download

A new method based on the combination of carrier element-free coprecipitation and flame atomic absorption spectrometric determination has been investigated for simultaneous separation and preconcentration of Pb(II) and Cu(II) ions in some environmental solid and liquid samples. The 2-{3-(4-methylbenzyl)-4-[2-(1H-indol-3-yl)ethyl]-5-oxo-4,5-dihydro-1H-1,2,4-triazol-1-yl}-N’-(phenylmethylene) acetohydrazide (MITA) was utilized as an organic coprecipitating agent without using a carrier element for coprecipitation of the analyte ions.

10p langthannam 29-12-2021 8 0   Download

Schiff base derivatives NBAR and NSAR were developed for selective detection of Al3+ in aqueous solution. UV-vis spectroscopic studies revealed that NBAR and NSAR showed marked sensitivity and selectivity to Al3+ in acetonitrile (ACN)/water (v/v, 1:1, pH 6.80). The NBAR and NSAR receptors bound Al3+ in a 2:1 stoichiometry with apparent binding constants 4.09 × 10 11 M−2 and 1.65 × 10 12 M−2, respectively. They also displayed distinct changes in color upon the alteration of free Al3+ levels in solution with reversible responses and showed little interference with other metal ions.

10p langthannam 29-12-2021 3 0   Download

In the present study, the antioxidant properties of peripherally and nonperipherally water-soluble tetra (quinoline 5-sulfonic acid) substituted metal-free (1, 2), Zn(II) (3, 4), Co(II) (5, 6), and Mn(III)Cl (7, 8) phthalocyanine (Pc) derivatives were reported. In order to determine the antioxidant properties of the Pc compounds, three different commonly known antioxidant methods were used: DPPH (α,α-diphenyl-β-picrylhydrazyl) radical scavenging, ferrous ion chelating, and reducing power assays.

10p tudichquannguyet 29-11-2021 10 0   Download

Freestanding tin oxide-boron oxide/reduced graphene oxide (SnO2 -B2 O3 /rGO) nanocomposite anode was produced for Li-ion cells. This binder-free flexible paper anode structure was fabricated by combining SnO2 -B2 O3 composite and graphene oxide which were synthesized through the sol–gel method and Hummers’ method, respectively. Field emission gun scanning electron microscopy, high-resolution transmission electron microscopy, energy dispersive X-ray spectrometer, Fourier transform infrared spectroscopy, Raman spectroscopy, and X-ray diffraction were utilized to characterize anode materials.

14p tudichquannguyet 29-11-2021 4 0   Download

In this study, the catalytic activity and stability of flowerlike hybrid horseradish peroxidase (HRP) nanobiocatalyst (HRPCu2+) obtained from Cu2+ ions and HRP enzyme in the polymerization reaction of guaiacol were analyzed. We demonstrated that HRP-Cu2+ and hydrogen peroxide (H2O2) initiator showed significantly increased catalytic activity and stability on the polymerization of guaiacol compared to that of free HRP enzyme. Poly(guaiacol) was observed with quite high yields (88%) and molecular weights (38,000 g/mol) under pH 7.

23p tudichquannguyet 29-11-2021 5 1   Download

Gram-negative bacterium Neisseria meningitidis, responsible for human infectious disease meningitis, acquires the iron (Fe3+) ion needed for its survival from human transferrin protein (hTf). For this transport, transferrin binding proteins TbpA and TbpB are facilitated by the bacterium. The transfer cannot occur without TbpA, while the absence of TbpB only slows down the transfer. Thus, understanding the TbpA-hTf binding at the atomic level is crucial for the fight against bacterial meningitis infections.

9p tudichquannguyet 29-11-2021 8 1   Download

The goal of many proteomics experiments is to determine the abundance of proteins in biological samples, and the variation thereof in various physiological conditions. High-throughput quantitative proteomics, specifically label-free LC-MS/MS, allows rapid measurement of thousands of proteins, enabling large-scale studies of various biological systems.

14p viwyoming2711 16-12-2020 10 1   Download

The (1–x)BiFe0.91(Mn0.47Ti0.53)0.09O3–xBaTiO3 (BFMT–BT) lead-free ceramics have been fabricated by using the conventional solid-state reaction method. The phase structure of BFMT−BT investigated with X-ray diffraction shows a single perovskite phase. Although 20% mol of Bi2O3 was added into the raw materials in excess, the evaporation of Bi3+ ions during calcining and sintering processes is from 20 to 30% wt. relative to other elements. The effect of BaTiO3 content on the electrical properties of BFMT−BT ceramic was investigated.

8p nguaconbaynhay9 03-12-2020 4 1   Download

Carbon ion Radiotherapy for prostate cancer is widely used, however reports are limited from single institute or short follow up. We performed a prospective observational study (GUNMA0702) to evaluate the feasibility and efficacy of carbon ion radiotherapy for localized and locally advanced prostate cancer.

8p vikuala271 13-06-2020 11 1   Download

Pancreatic adenocarcinoma is a high-mortality neoplasm with a documented 5-years-overall survival around 5%. In the last decades, a real breakthrough in the treatment of the disease has not been achieved.

7p vikuala271 13-06-2020 7 1   Download