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Abstract: The photocatalytic destruction of organic substances is an efficient method for the production of high-quality purified water for various applications. For photocatalytic purposes, titania is most widely studied due to its low cost, availability, untoxicity, and stable chemical structure. The combined application of a photocatalyst and hydrogen peroxide increases the degree of ecotoxicants destruction to CO2, H2O, and inorganic ions (mineralization) and shortens the reaction time to decrease the water treatment expenditures. Photocatalytic destruction kinetics was studied for a non-ionic surfactant, namely, octylphenol ethoxylate (Triton X-100) with hydrogen peroxide in an aqueous medium in reactors with immobilized TiO2. The conditions for achieving a high degree of mineralization of Triton X-100 (84–88% for 4–5 h at C0= 50 mg/dm3) were established in the H2O2/TiO2/UV (λ = 254 nm) system in a reactor with TiO2immobilized on a large-pore ceramic support alongside with its essential advantages as compared to the TiO2/UV system, where the maximum degree of mineralization of Triton X-100 was 2.5 times lower. The possibility of attaining a high degree of mineralization with hydrogen peroxide for Triton X-100 (up to 92% on TOC basis of 2 h) was demonstrated in a quartz reactor with a Degussa P-25 TiO2film on its inner surface at the external irradiation mode (λ = 254 nm) without additional TiO2powder.

Abstract—: Samples of amorphous silicon dioxide (SiO2) were obtained by acid decomposition of mineral raw materials (nepheline). Their physicochemical, acid–base, structural, and surface properties were studied by chemical analysis, potentiometric titration, and by the methods of Parks, Brunauer–Emmett–Taylor (BET), Barrett–Joyner–Halenda (BJH), and others. It was determined that the obtained SiO2samples are almost identical to pyrogenic amorphous silicon dioxide produced from reactive raw materials (pharmaceutical drug Polisorb MP) in content of impurities, pH of the aqueous extract, and pH values of the isoionic point and the zero-charge point and have larger values of specific external surface area and specific pore volume (by a factor of 1.1–1.9 and ~1.4, respectively). Based on the found values of the specific capacity of the adsorption monolayer of the surface of the SiO2samples and the Gibbs free energy change of sorption (ΔG0), it was concluded that the method of their preparation does not significantly affect the physicochemical properties of their surfaces and the mechanism of nitrogen sorption. On the basis of the results obtained, it was assumed that silicon dioxide produced by acid processing of mineral raw materials is promising as an enterosorbent in therapeutic practice.

Abstract: Alkylphenolpolyethoxylates whose bioresistant metabolites (alkylphenols, short-chain alkylphenolpolyethoxylates and alkylphenoxycarboxylic acids) are compounds with hormonal activity that pose a serious threat to living organisms are among the main types of nonionic surfactants widely used in industry and everyday life. Advanced oxidation processes (AOPs)—in particular, photocatalytic processes—are capable of effectively removing such impurities from an aqueous medium. However, photocatalytic oxidation of some synthetic surfactants with oxygen until their complete mineralization proceeds slowly. The combined use of a photocatalyst and oxidizing agents that are stronger than oxygen contributes to an increase in the degree of mineralization of organic impurities and a decrease in the reaction time compared to those achieved with separate treatment by both methods, which gives rise to the lower cost of water purification and improves the environmental friendliness of the combined process. The photocatalytic processes of degradation of nonionic surfactant octylphenol ethoxylate (Triton X-100) in an aqueous medium by ozone (O3), by ozone and UV radiation jointly (O3/UV), and by ozone and atmospheric oxygen in a TiO2Degussa P-25 suspension (O3/TiO2/UV and O2/TiO2/UV) under UV irradiation with a DB-15 low-pressure mercury quartz lamp (λ = 254 nm) have been studied. The parameters of photocatalytic ozonation have been determined to ensure the nearly complete destruction of Triton X-100 (97% according to total organic carbon). The advantages of photocatalytic ozonation of a Triton X-100 solution in comparison with ozonation, O3/UV treatment, and photocatalytic oxidation with air oxygen are demonstrated.

Abstract: Titanium dioxide, one of the most important photocatalysts for the oxidation of compounds dissolved in water, is active only under ultraviolet irradiation and inactive in the visible spectral region due to its broad bandgap. A promising strategy for the creation of active TiO2samples able to efficiently utilize visible sunlight and thereby to essentially decrease the cost of the photocatalytic treatment of natural and waste water is the introduction of several dopants. The efficiency of nitrogen doped and nitrogen and iron ion codoped titania samples synthesized by the sol-gel method with a bandgap narrowed to 2.59–2.99 eV in the photocatalytic destruction of humic acid (HA) in water (C= 55–60 mg/dm3) with atmospheric oxygen and hydrogen peroxide was studied depending on pH and a radiation source: an SVD-120 mercury quartz lamp (λ > 200 nm) or a GE CMG70 metal halide lamp (λ > 360 nm). The efficiency of doped TiO2samples in the photocatalytic oxidation of aqueous HA solutions depended on the iron content (0–1% of Fe), the used oxidant, pH of the medium, and the irradiation mode. A much higher degree of HA destruction was attained in an acidic medium (pH02.4) as compared to a neutral medium (pH07) in both irradiation modes. The application of hydrogen peroxide increased the degree of photocatalytic HA mineralization in the presence of all the synthesized samples in both irradiation modes as compared to the oxidation with dissolved oxygen and essentially approached the efficiency of synthesized photocatalysts to standard Degussa P-25 TiO2. On the whole, N-TiO2was most active among the synthesized photocatalysts. No clear dependence of the HA destruction degree on the Fe content in the samples (Fe,N-TiO2; 0.25–1.0%) were established at studied destruction parameters. In general, the codoped samples (Fe,N-TiO2) essentially inhibited HA destruction and, in a neutral medium, the inhibiting effect became stronger with increasing iron content in a sample in both irradiation modes. It seems probable that the recombination of photogenerated electron–hole charge carriers was intensified due to the selected method of N-TiO2codoping with Fe3+ions or the range of dopant concentrations.

Abstract: Developing titanium dioxide (TiO2) samples able to absorb and effectively utilize both ultraviolet radiation and visible light will lead to considerable reduction in costs of photocatalytic purification of natural and waste waters. Using the sol–gel method, we synthesized nanoscale titanium dioxide samples doped with nitrogen or co-doped with nitrogen and iron ions, with the samples having a narrower band gap of 2.59–2.99 eV. The synthesized N-TiO2and (Fe,N)-TiO2samples and the standard titanium dioxide Degussa P-25 are compared in terms of their activities in photocatalytic oxidation of aqueous salicylic acid solutions (0.2 mmol/L, pH 4) by dissolved oxygen or hydrogen peroxide upon irradiation with light from a SVD-120 lamp (λ > 200 nm) or a metal-halide GE CMH70 lamp (λ > 360 nm). The relative photocatalytic activity of doped TiO2samples in oxidation of aqueous salicylic acid solutions depends on their iron content (0–1% Fe), the type of oxidant used, and the irradiation conditions. In photocatalytic oxidation with oxygen, samples N-TiO2(λ > 200 nm) and (Fe,N)-TiO2(1.0% Fe) (λ > 360 nm) exhibit the highest degree of mineralization of salicylic acid among the doped TiO2samples, while (Fe,N)-TiO2(0.5% Fe) is the most effective in degradation of salicylic acid by hydrogen peroxide. Using hydrogen peroxide raises the degree of photocatalytic mineralization of salicylic acid in the presence of any of the synthesized samples under both types of irradiation conditions, compared to its oxidation by dissolved oxygen. In addition, the use of H2O2levels off the differences in the activity between synthesized TiO2samples with different doping level of iron that are observed in the O2/TiO2/UV photocatalytic system upon irradiation with UV–visible light (λ > 200 nm), while the extent of salicylic acid degradation in the presence of most active synthesized catalysts is considerably closer to that achieved with the standard photocatalyst.

An integrated approach is applied to reveal fine changes in the surface-normal structure of 1,2-dimyristoyl-sn-glycero-3-phospho-l-serine (DMPS) monolayers at the air–lipid–water interface occurring in a liquid expanded (LE)–liquid condensed (LC) transition. The combination of the Langmuir monolayer technique, X-ray reflectometry, and molecular dynamics (MD) modeling provides new insight into the molecular nature of electrostatic phenomena in different stages of lipid compression. A homemade setup with a laboratory X-ray source (λ = 1.54 Å) offers a nondestructive way to reveal the structural difference between the LE and LC phases of the lipid. The electron density profile in the direction normal to the interface is recovered from the X-ray reflectivity data with the use of both model-independent and model-based approaches. MD simulations of the DMPS monolayer are performed for several areas per lipid using the all-atom force field. Using the conventional theory of capillary waves, a comparison is made between the electron density profiles reconstructed from the X-ray data and those calculated directly from MD modeling, which demonstrates remarkable agreement between the experiment and simulations for all selected lipid densities. This confirms the validity of the simulations and allows an analysis of the contributions of the hydrophobic tails and hydrated polar groups to the electron density profile and to the dipole component of the electric field at the interface. According to the MD data, the dependence of the Volta potential on the area per lipid in the monolayer has a different molecular nature below and above the phase transition. In the LE state of the monolayer, the potential is determined mostly by the oriented water molecules in the polar region of the lipid. In the LE–LC transition, these molecules are displaced to the bulk, and their effect on the Volta potential becomes insignificant compared with the contribution of the hydrophobic tails. The hydrophobic tails are highly ordered in the state of the liquid crystal so that their dipole moments entirely determine the growth of the potential upon compression up to the monolayer collapse.

Background/objectives:: Chungkookjangis a Korean representative fermented soybean food. In this study, we investigated the effect of Korean traditional Chungkookjangcompared with placebo on body composition, dyslipidemia and risk factors for atherosclerosis in overweight/obese subjects. Subjects/methods:: This double-blind, randomized, controlled crossover trial was conducted on 120 overweight/obese subjects, aged 19–29 years. Subjects were randomly divided into a Chungkookjang(n=60) or a placebo (n=60) group. After 12 weeks, the groups were crossed over for an additional 12 weeks. During the intervention period, subjects were asked to maintain their usual diet and activity and not to take any functional foods or dietary supplements. The anthropometric measures, lipid profiles and atherogenic indices were determined at baseline and at the end of each 12-week period. Results:: The anthropometry measurements, percentage body fat, lean body mass, waist circumference and waist-to-hip ratio of women in the Chungkookjanggroup were significantly improved compared with the placebo group. Lipid profiles and high-sensitivity C-reactive protein of women in Chungkookjangwere significantly improved. The atherogenic indices of apolipoprotein B/apolipoprotein A1 decreased in both the placebo and the Chungkookjanggroup, and it also decreased below 0.55 for all the men and women in the Chungkookjanggroup. Conclusions:: In conclusion, these results suggest that supplementation with Chungkookjangmay improve body composition and risk factors for cardiovascular disease in overweight and obese adults.

Purpose:Spinal cord injury (SCI) is a catastrophe that causes disabilities and permanently changes people’s lives. The people have to adapt to the loss of self-care ability and may need long-term rehabilitation. The recovery can be problematic, affecting physiological, psychological, and financial aspects of life. The purpose of this study was to explore the lived experiences of persons with SCI living in Taiwan. Methods:In 2009, we conducted a qualitative study on 10 participants with SCI recruited from the Association of Spinal Cord Injury Persons in Taiwan. Open-ended interviews were conducted using a guide and tape recorder for subsequent transcription. A phenomenological method was used to collect data by interviews. Results:The core experience of persons with SCI was “finding a way to cope,” which was a process from despair to self-acceptance and composed of four categories: (a) shock and unpreparedness for the injury: the catastrophe of the injury itself and the underrecognition of physiological disabilities; (b) panic and fear: denying the injury and yearning for a miracle; (c) abyss of despair: imprinting of life, bearing the agony alone, and chaos of life; and (d) reflection on the meaning of life: adaptation to physical disabilities, self-acceptance, and growth. Conclusions:Our research was descriptive and focused on the structure of the lived experiences of persons with SCI. Many issues of inequality also revealed physical disabilities, such as difficulty looking professional, resulting in burden of stress and frustration. These results highlight persons with SCI should be classified as case management and integration of social welfare resources to facilitate care for persons with SCI after discharge.

We have developed two new types of lasers based on quantum-confined semiconductor optical amplifiers with an acousto-optic tunable filter in an external fibre ring cavity. The lasers offer continuous wavelength tuning ranges from 780 to 885 and from 880 to 1010 nm, 20 mW of cw output power, and a tuning rate up to 104 nm s-1 at an instantaneous spectral linewidth less than 0.1 nm.