Evaluations of physico-chemical properties of TiO2/clinoptilolite synthesized via three methods on photocatalytic degradation of crystal violet

Different preparation routes for Ti O_2-supported natural and synthetic clinoptilolite(Ti O_2/CP) composites were thoroughly investigated on the basis of sol–gel, hydrothermal, and in-situ hydrothermal methods.The micro-structural features and physicochemical properties of resultant Ti O_2/CPs were characterized via X-ray diffraction patterns, scanning(transmission) electron microscope images, Fourier transform infrared spectra, inductively coupled plasma-optical emission spectrometry methods, BET-isotherms,UV–visible spectra, and surface charge potential distributions. The results showed that in-situ hydrothermal method led to well dispersions of loaded-Ti O_2 particles on the surface of leaf-like CP, while obviously aggregated Ti O_2 on a relatively distorted structure of CP was obtained using sol–gel and hydrothermal methods. Their adsorptive and photocatalytic efficiencies for removal of crystal violet(CV) dye in aqueous solution were also explored under UV-irradiations. The results demonstrated that Ti O_2/CPs synthesized via sol–gel and in-situ hydrothermal methods presented the excellent performances with 98%removal efficiencies as compare to the bare commercial Ti O_2 which achieved 53% removal of CV dye.While, the in-situ hydrothermally synthesized Ti O_2/CPs were the best due to their moderate energy cost,highest adsorption capacities and removal efficiencies. Particularly, the synthetic CPs as supports exhibited synergetic photocatalytic activities for the degradation of CV dye, which is attributed to their high surface areas, better adsorption capability, and fine dispersion of Ti O_2 particles. Adsorption and degradation kinetics of CV dye were found to follow the pseudo-second and pseudo-first order models,respectively.     

PCR‐RFLP and DAMD‐PCR genotyping for Salvia species

BACKGROUND: Identification of genotypes in Salvia is complicated owing to the morphological similarity and common occurrence of natural hybridisation within Salvia species. Species‐ and genotype‐specific DNA markers are very useful for plant identification, breeding and preservation programmes and can also provide a general overview on the prediction of plant essential oil yield. RESULTS: Polymerase chain reaction restriction fragment length polymorphism (PCR‐RFLP) was used for identification of species‐specific chloroplast and mitochondrial organelle DNA markers, and directed amplification of minisatellite DNA polymerase chain reaction (DAMD‐PCR) was used for genotyping of plant materials. Application of PCR‐RFLP resulted in species‐specific DNA markers, and use of DAMD‐PCR resulted in reproducible DNA patterns that are useful in Salvia genetic studies. Multivariate cluster analysis and principal coordinate analysis indicated that there were relationships between DNA marker patterns and essential oil yields at the species level. CONCLUSION: Results showed that genetic variations in Salvia are wide, and DNA patterns of relatedness among plant species appeared to correlate with essential oil yields. Further studies are required to confirm the application of PCR‐RFLP and DAMD‐PCR markers for selection of Salvia species with higher essential oil yield. Copyright © 2008 Society of Chemical Industry     

A feasibility study of grid-connected photovoltaic systems in Istanbul,Turkey

The application of renewable energy sources in electric power systems is increasing. There is a growing need for economic evaluation to inform photovoltaic (PV) allocation decisions for a range of decision-makers. In this study, power output and temperature data collected from PV modules in Istanbul, Turkey in 2009 have been analyzed to determine solar power generation potential. In addition to the measurements, technical and commercial parameters were also used to perform the evaluation. Different tariffs such as time-of-use and feed-in tariffs were considered in this study.     

Statistical pattern recognition for Structural Health Monitoring using time series modeling: Theory and experimental verifications

Statistical pattern recognition methodologies have gained considerable attention for Structural Health Monitoring (SHM) applications to detect changes in a structure (e.g. damage). For most of such applications, outlier analysis of the damage sensitive features obtained from the SHM data is used to detect the changes in the structure. There are a number of different approaches used by different research groups and it is widely accepted that success of a certain methodology may depend on the structure and/or structural change to be identified. Therefore, it is very important that promising methodologies are verified by using different test structures and damage cases. The main objective of this study is to investigate statistical pattern recognition methods in the context of SHM using different laboratory structures. Time series modeling, i.e. auto-regressive models, is used in conjunction with Mahalanobis distance-based outlier detection algorithms to identify different types of structural changes on different test structures. Similar approaches were reported in the literature but here the methodology is modified by using random decrement functions to eliminate the effects of the exogenous input. Then a number of tests are conducted by using two different test structures in laboratory conditions in order to evaluate the results in a comparable fashion. The first test specimen is a simply supported steel beam where the second structure is a highly redundant steel grid structure. Various damage conditions are simulated by using these structures. The ambient vibration data is analyzed by using the methodology described and results are presented. Finally, the advantages and drawbacks of the methodology are discussed in the light of experimental results.     

Effect of the catalyst supports on the removal of perchloroethylene (PCE) over chromium oxide catalysts

The oxidation of perchloroethylene (PCE) was investigated over chromium oxide catalysts supported on TiO₂, Al₂O₃, SiO₂, SiO₂–Al₂O₃ and activated carbon. The phase of chromium oxide on the catalyst surface is critical for the oxidation of PCE. The catalytic activity of PCE removal enhances as the formation of Cr(VI) species on the catalyst surface increases. The surface area and the type of the catalyst supports were also essential for high performance in the PCE oxidation. In addition, the structure of Cr(VI) on the catalyst surface also plays an important role for the decomposition of PCE. The polymerized Cr(VI) mainly formed by the interaction of metals with the support is the active reaction site for the present reaction system. CrO_x/TiO₂ reveals the strongest PCE removal activity among the catalysts examined in the present study. This revised version was published online in July 2006 with corrections to the Cover Date.     

Inelastic Scattering off a Nanomechanical Resonator

We study the dephasing rate of conduction electrons due to local vibrational modes. Bosonization allows us to evaluate the full T-matrix analytically. The inelastic scattering rate is strongly influenced by multiphonon excitations. For higher frequencies, it saturates to a finite, coupling dependent value. In the strong coupling limit, the phonon is almost completely softened, and the inelastic cross section reaches its maximal value. This represents a magnetic field insensitive contribution to the dephasing time in mesoscopic systems, in addition to magnetic impurities.      

Toxicity of copper oxide nanoparticles: a review study

Copper oxide nanoparticles (CuO NPs) use has exponentially increased in various applications (such as industrial catalyst, gas sensors, electronic materials, biomedicines, environmental remediation) due to their flexible properties, i.e. large surface area to volume ratio. These broad applications, however, have increased human exposure and thus the potential risk related to their short‐ and long‐term toxicity. Their release in environment has drawn considerable attention which has become an eminent area of research and development. To understand the toxicological impact of CuO NPs, this review summarises the in‐vitro and in‐vivo toxicity of CuO NPs subjected to species (bacterial, algae, fish, rats, human cell lines) used for toxicological hazard assessment. The key factors that influence the toxicity of CuO NPs such as particle shape, size, surface functionalisation, time–dose interaction and animal and cell models are elaborated. The literature evidences that the CuO NPs exposure to the living systems results in reactive oxygen species generation, oxidative stress, inflammation, cytotoxicity, genotoxicity and immunotoxicity. However, the physio‐chemical characteristics of CuO NPs, concentration, mode of exposure, animal model and assessment characteristics are the main perspectives that define toxicology of CuO NPs.Inspec keywords: catalysts, nanofabrication, reviews, oxidation, toxicology, gas sensors, cellular biophysics, copper compounds, nanoparticles, biochemistryOther keywords: copper oxide nanoparticles, environmental remediation, short‐ term toxicity, long‐term toxicity, human cell lines, CuO NPs exposure, physiochemical characteristics, mode of exposure, animal model, ssessment characteristics, toxicology, time‐dose interaction, oxidative stress, inflammation, cytotoxicity, genotoxicity, immunotoxicity, toxicological hazard assessment, algae species, bacterial species, fish, rats, CuO     

Nutraceuticals and Functional Foods: The Foods for the Future World

The health and wellness of human beings is largely dictated by the consumption of nutritious foods. Various studies have linked foods as helpful in combating a number of degenerative diseases; as such, a lot of research on functional attributes linked directly to the health benefits of various plant and animal foods have been witnessed in recent years. Although vast number of naturally occurring health-enhancing substances are of plant origin, there are a number of physiologically active components in animal products as well that deserve attention for their potential role in optimal health. Consumption of biologically active ingredients in fruits and vegetables has been linked to help combat diseases such as cancer, cardiovascular diseases, obesity, and gastrointestinal tract disorders. Lot of research is required to substantiate the potential health benefits of those foods for which the diet–health relationships are not sufficiently validated, and create a strong scientific knowledge base for proper application of naturally present foods in combating various diseases and disorders.     

Application of TOPSIS methodology to determine optimum hazelnut cake concentration and high pressure homogenization condition for hazelnut milk production based on physicochemical,structural and sensory properties

Vegetable milks containing antioxidants, fatty acids and vitamins can be recommended as an alternative to animal milks cause some health problems like lactose intolerance and milk protein allergy. Hazelnut oil cake which is a waste from hazelnut oil production cannot be used for human nutrition. Cold press hazelnut cake must be evaluation as food materials. The aim of this study was to evaluate the effect of cold pressed hazelnut cake concentration (5, 10, 15% w/v) and high pressure homogenization (HPH) (up to 100 MPa) on the physicochemical, structural and sensory properties of hazelnut milk and also determined the best conditions for hazelnut milk production by TOPSIS approach. Hazelnut milks produced from 15% hazelnut cake had the best physicochemical properties and physical stability, but the sensory properties of the milks were not acceptable due to viscoelastic behaviors. Physicochemical properties, physical stability and sensory characteristics of hazelnut milks were significantly affected by homogenization pressure (P?<?0.05). Colloidal stability and sensory properties of hazelnut milks were improved by increasing homogenization pressure. The viscosity values of hazelnut milks with 10 and 15% hazelnut cakes were significantly decreased by increasing the homogenization pressure. TOPSIS approach showed that 10% hazelnut cake concentration and 100 MPa homogenization pressure was the best condition for an acceptable hazelnut milk production.