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The mesoporous silica particles were prepared by the sol–gel method in one-step synthesis, in acidic conditions, from tetraethoxysilane (TEOS) and methyltriethoxysilane (MTES), varying the mole ratio of the silica precursors. Nitric acid was used as catalyst at room temperature and hexadecyltrimethyl ammonium bromide (CTAB) as structure directing agent. Optical properties, porosity and microstructure of the materials in function of the MTES/TEOS ratio were evaluated using infrared spectroscopy, nitrogen adsorption and small angle X-ray scattering. All materials showed the ordered pore structure and the high specific surfaces, making them suitable as the drug delivery systems. Drug loading and release tests using ketoprofen were performed to assess their performance for drug delivery applications. The amount of the methylated precursor used in the synthesis had little effect on the drug loading capacity, but had a strong influence on the initial rate of the drug release.

The aim is to re-dimension More's law in nano-chemical devices by modelling quasiparticle couplings (bondonic and bondotic) as QBits impulses on chemical-physical nanocompounds (graphene lattices with Stone-Wales rotations topological defects, but also for molecules governed by nano-mechanical chemical bonds) and their propagations as dynamic donors of chemical bond and coupled electron pairs instead of electrons and single atoms as "quantum dots". This represents the quantum-chemical basis of graphenetronics (semiconductors, transistors, and integrated circuits based on topological defective graphene) and of photo-activated moletronics (molecular machines). The paper presents the correlation of quantum potentials of electrochemical tunnelling with associated electrochemical currents and with electro-photo-chemical activation mechanism of molecular machines. [ABSTRACT FROM AUTHOR]

An immunosensors/sequential injection analysis system is proposed for the assay of thyroid hormones free L-T4 and free L-T3 in blood samples. The working concentration ranges for free L-T4 and free L-T3, are between 2.0 and 720.0 pmol/L and between 2.0 and 340.0 pmol/L, respectively, with detection limits of 1.0 and 1.7 pmol/L, respectively. The selectivity of the immunosensors, as well as the recovery tests done for free L-T4 and free L-T3 (99.90 ± 0.01% (n = 10) and 99.94 ± 0.02% (n = 10)), made the immunosensors/sequential injection analysis system suitable for the direct assay of thyroid hormones in blood samples. [ABSTRACT FROM AUTHOR]

Electroflotocoagulation is used for the treatment of liquid wastes of various origins, containing suspended matter. The metal hydroxide formed by electrochemical metallic ions generation acts to aggregate the colloidal impurities, and the hydrogen bubbles evolved at the cathode allow flotation of foam containing the impurities. The aggregates formed (containing the impurities) and lifted above the solution can then be removed. Electroflotocoagulation (simultaneous electrocoagulation and electroflotation) is studied as partially treatment method for non-ferrous heavy metals metallurgy wastewater (levigates). A pilot scale reactor for electroflotocoagulation is proposed. Different parameters are studied: pH variation during the process, anodic and cathodic current densities, cell voltage, energy consumption, hydrogen evolution etc. [ABSTRACT FROM AUTHOR]

Changing fuel consumption to a more ecological environmentally alternative is replacing fossil fuels with fuels generated from renewable resources. Ethanol, a renewable fuel, can be produced mainly from crops, lignocellulosic biomass and different other environmental wastes. Although ethanol has been produced mainly from crops, there is a great interest in using cheaper lignocellulosic materials as a feedstock for ethanol production. The aim of this paper is study of dilute acid hydrolysis of different types of biomass using the microwaves radiation. Acid hydrolysis of biomass will be accomplished in a speedwave TMMVS-2 system, at 130-170°C, for 35 minutes, at high pressure. Dilute-acid hydrolysis is a cheap and fast process to obtain sugar from lignocelluloses materials. The suggested method offers multiple advantages: an important decrease of energy consumption, reducing of reaction time and reaction temperature optimization by the microwave generator. The resulting compounds were analysed by HPLC chromatography and UV-VIS spectroscopy. [ABSTRACT FROM AUTHOR]

Quantum electrochemistry implies concepts, models, and approaches from a wide range of science including mathematics, physics, chemistry, mechanics, engineering, energy, biology, genetics, geology, soil sciences, etc. The rapid development of many areas in nanotechnology has determined the occurrence of new possibilities in the design of functional materials with special properties: optical, photonic, electronic, electrical, thermal, mechanical, chemical, biochemical, and so on [1]. These materials could be realized for specific applications, such as solar cells, rechargeable batteries, biosensors, supercapacitors, and others. The route from micromolecules to dynamic molecular nanosystems will be completed using the information obtained from the studies and works carried out so far [2, 3], which will be assembled as shown in Figure 1. Starting from the application of electrochemistry to the specific case of light-activated molecular machines, through the path integral formalism, will be established quantum electrochemical models applicable to molecular machines; these will subsequently be used for various photovoltaic applications, and the final result will be the quantum molecular electro-photo machines. [ABSTRACT FROM AUTHOR]

Graphene, a one-atom-thick honeycomb lattice of carbon atoms has extraordinary optical and electrical features like high electron mobility (100 times greater than silicon). The present challenge is to design and exploit semiconductorgraphene (SG), with controlled conductivity. Accordingly, two new forms of graphene are studied and employed, as new classes of n-doped, and p-doped semiconductors, so producing the so called, e-SG (electron-type semiconductor graphene, based on topological defective Graphene, as appeared by inherent Stone-Wales topological rotations in pristine Graphene 0-G) and h- SG (hole-type semiconductor graphene, when the structurally defective graphene is present). [ABSTRACT FROM AUTHOR]

The studies were focused on the relationship between morphology features and synthesis variables, looking for their implications in the drug loading and release capacities. Increasing the amount of methylated tri-alcoxide toward the tetra-alcoxide precursor caused shrinkage of the hexagonally ordered mesoporous structure and also the reduction of the pore diameters, while the total pore volumes and surface areas remain high and suitable for drug loading. In drug release profiles: silica prepared with the largest amount of hydrophobic precursor retained about twice as much of drug, compared with the sample obtained of pure TEOS.The studies were focused on the relationship between morphology features and synthesis variables, looking for their implications in the drug loading and release capacities. Increasing the amount of methylated tri-alcoxide toward the tetra-alcoxide precursor caused shrinkage of the hexagonally ordered mesoporous structure and also the reduction of the pore diameters, while the total pore volumes and surface areas remain high and suitable for drug loading. In drug release profiles: silica prepared with the largest amount of hydrophobic precursor retained about twice as much of drug, compared with the sample obtained of pure TEOS. [ABSTRACT FROM AUTHOR]

A sequential injection analysis/immunosensor system is proposed for the analysis of thyroxine (L-T4) in serum and in pharmaceutical formulations with a rate of 75 samples/hour. The immunosensor design is based on the physical immobilization of anti-L-T4 in carbon paste. The working concentration range of the immunosensor in the sequential injection analysis system is between 36 and 1080 ng/mL with a limit of detection of 24.6 ng/mL. The system is very reliable and very easy to design and operate.