Titania nanofibers were fabricated using the industrial Nanospider(TM) technology. The preparative protocol was optimized by screening various precursor materials to get pure anatase nanofibers. Composite films were prepared by mixing a commercial paste of nanocrystalline anatase particles with the electrospun nanofibers, which were shortened by milling. The composite films were sensitized by Ru-bipyridine dye (coded C106) and the solar conversion efficiency was tested in a dye-sensitized solar cell filled with iodide-based electrolyte solution (coded Z960). The solar conversion efficiency of a solar cell with the optimized composite electrode (η = 7.53% at AM 1.5 irradiation) outperforms that of a solar cell with pure nanoparticle film (η = 5.44%). Still larger improvement was found for lower light intensities. At 10% sun illumination, the best composite electrode showed η = 7.04%, referenced to that of pure nanoparticle film (η = 4.69%). There are non-monotonic relations between the film's surface area, dye sorption capacity and solar performance of nanofiber-containing composite films, but the beneficial effect of the nanofiber morphology for enhancement of the solar efficiency has been demonstrated.

• MeSH
• 2,2'-dipyridyl analogy a deriváty   chemie   MeSH
• barvicí látky chemie   MeSH
• elektrody MeSH
• elektrolyty chemie   MeSH
• nanočástice chemie   MeSH
• nanovlákna chemie   ultrastruktura   MeSH
• organokovové sloučeniny chemie   MeSH
• polymery chemie   MeSH
• sluneční energie * MeSH
• titan chemie   MeSH
• zdroje elektrické energie * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

A solar drying was investigated as one of perspective techniques for fish processing in Cambodia. The solar drying was compared to conventional drying in electric oven. Five typical Cambodian fish species were selected for this study. Mean solar drying temperature and drying air relative humidity were 55.6 °C and 19.9%, respectively. The overall solar dryer efficiency was 12.37%, which is typical for natural convection solar dryers. An average evaporative capacity of solar dryer was 0.049 kg · h(-1). Based on coefficient of determination (R(2)), chi-square (χ(2)) test, and root-mean-square error (RMSE), the most suitable models describing natural convection solar drying kinetics were Logarithmic model, Diffusion approximate model, and Two-term model for climbing perch and Nile tilapia, swamp eel and walking catfish and Channa fish, respectively. In case of electric oven drying, the Modified Page 1 model shows the best results for all investigated fish species except Channa fish where the two-term model is the best one. Sensory evaluation shows that most preferable fish is climbing perch, followed by Nile tilapia and walking catfish. This study brings new knowledge about drying kinetics of fresh water fish species in Cambodia and confirms the solar drying as acceptable technology for fish processing.

• MeSH
• manipulace s potravinami přístrojové vybavení   metody   MeSH
• ryby * MeSH
• sluneční energie * MeSH
• teoretické modely * MeSH
• vysoušení přístrojové vybavení   metody   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Kambodža MeSH

• MeSH
• lidé MeSH
• periodicita MeSH
• sluneční energie MeSH
• srdeční frekvence MeSH
• Check Tag
• lidé MeSH

The potential of solar cells have not been fully tapped due to the lack of energy conversion efficiency. There are three important mechanisms in producing high efficiency cells to harvest solar energy; reduction of light reflectance, enhancement of light trapping in the cell and increment of light absorption. The current work represent studies conducted in surface modification of single-crystalline silicon solar cells using wet chemical etching techniques. Two etching types are applied; alkaline etching (KOH:IPA:DI) and acidic etching (HF:HNO3:DI). The alkaline solution resulted in anisotropic profile that leads to the formation of inverted pyramids. While acidic solution formed circular craters along the front surface of silicon wafer. This surface modification will leads to the reduction of light reflectance via texturizing the surface and thereby increases the short circuit current and conversion rate of the solar cells.

• MeSH
• analýza selhání vybavení MeSH
• design vybavení MeSH
• hydroxidy chemie   MeSH
• křemík chemie   MeSH
• kyseliny chemie   MeSH
• nanočástice chemie   ultrastruktura   MeSH
• povrchové vlastnosti MeSH
• sloučeniny draslíku chemie   MeSH
• sluneční energie * MeSH
• smáčivost MeSH
• zdroje elektrické energie * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

• MeSH
• sluneční energie MeSH
• znečištění životního prostředí prevence a kontrola   MeSH

• MeSH
• agrese MeSH
• chování psychologie   MeSH
• davové chování MeSH
• občanské nepokoje psychologie   MeSH
• počasí MeSH
• sluneční energie MeSH

We investigate the impact of solar activity changes on mortality from cardiovascular causes of death in the period 1994-2011 in the Czech Republic. This period coincides with the time of solar cycle no. 23 and the surrounding minima when there was an unusually low level of solar activity. We use long-period daily time series of numbers of deaths by cause, solar activity indices (the relative sunspot number, and the intensity of solar radio flux), geomagnetic indices (Kp-the planetary index that indicates the fluctuation rate of horizontal components of the geomagnetic field, the Auroral Electrojet, and the disturbance storm time), and physical parameters describing the ionospheric effects (the critical frequency of the ionospheric F2 layer and the content of free electrons in the ionosphere). The results of the analysis confirm the hypothesis that there is no direct correlation between the geomagnetic solar index, Kp, and the number of deaths from acute myocardial infarction (code I21) or brain stroke (code I64) during the maxima of the solar cycle. On the other hand, the ionospheric parameters explain a greater part of the variability in the number of deaths for acute myocardial infarction or brain stroke than the model with solar parameters. The analysis shows that, because the values are geographically specific, the ionospheric parameters may describe the variability in the number of deaths from cardiovascular causes better than the solar indices. The cardiovascular diseases thus respond to the changes in the solar activity and to abnormal solar events indirectly through a concentration of electrical charges in the earth's environment.

• MeSH
• časové faktory MeSH
• cévní mozková příhoda diagnóza   mortalita   MeSH
• ekosystém * MeSH
• elektromagnetická pole MeSH
• infarkt myokardu diagnóza   mortalita   MeSH
• kardiovaskulární nemoci diagnóza   mortalita   MeSH
• kosmické záření MeSH
• lidé MeSH
• lineární modely MeSH
• příčina smrti MeSH
• prognóza MeSH
• rizikové faktory MeSH
• shluková analýza MeSH
• sluneční aktivita * MeSH
• sluneční energie MeSH
• stochastické procesy MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika epidemiologie   MeSH

• MeSH
• kosmické záření škodlivé účinky   MeSH
• sluneční energie škodlivé účinky   MeSH
• sluneční záření škodlivé účinky   MeSH
• zdraví MeSH
• životní prostředí MeSH

• MeSH
• kardiovaskulární nemoci etiologie   MeSH
• magnetismus MeSH
• Měsíc MeSH
• náhlá smrt etiologie   MeSH
• počasí MeSH
• sluneční energie MeSH

• MeSH
• antioxidancia MeSH
• biopotraviny MeSH
• péče o kůži MeSH
• potravní doplňky MeSH
• stárnutí kůže etnologie   MeSH
• Publikační typ
• příručky MeSH

• Konspekt
• Odívání. Péče o tělo
• NLK Obory
• dermatovenerologie
• nutriční terapie, dietoterapie a výživa
• estetická medicína