Metal Halide Lamps Research Articles

Visible-light-driven photocatalytic disinfection of raw surface waters (300–5000 CFU/mL) using reusable coated Ru/WO3/ZrO2

We selected ruthenium (Ru) to improve the photocatalytic activity of a WO3/ZrO2 composite. The synthesized Ru/WO3/ZrO2 was then compared to a benchmark photocatalyst (S-TiO2) in terms of photocatalytic disinfection of raw surface waters collected from the Nile Delta region, Egypt. The photocatalysts were immobilized on aluminum plates with polysiloxane to test them in repetitive cycles under the irradiation of a metal-halide lamp. Bacterial concentrations in the raw waters ranged from 300 to 5000 CFU/mL (CFU: colony-forming units) and different species and genus were detected including gram-negative (e.g., shigella, salmonella, vibrio parahaemolyticus, and vibrio cholera) and gram-positive bacteria (e.g., enterococcus). Ru/WO3/ZrO2 deactivated over 90 % of the bacterial content within 120 min for most sources, whereas S-TiO2 did not perform as highly. The bacterial count after 240 min of irradiation was below the detection limit for all different water sources. Moreover, the inhabitation of photocatalytic disinfection by natural organic matter (NOM) was investigated. Ru/WO3/ZrO2 was stable for four continuous cycles (960 min in total), suggesting the viability for practical application.

Effect of Different Spectral Power Distributions on Mesopic Visual Performance with Blue Light-filtering Intraocular Lens

ABSTRACT The purpose of this work is to analyze the interaction between the spectral transmittance of old-aged subjects, before and after cataract surgery and blue light-filtering intraocular lens implantation, and the spectral power distribution of common street lamps, under conditions typical of nighttime driving. We analyzed contrast threshold and visual reaction time in off-axis vision at different mesopic illumination conditions provided by high-pressure sodium and metal halide lamps. Three groups of subjects with different spectral transmittances participated: young subjects as control group, old-aged subjects with senile cataracts and the same subjects after cataract surgery and blue light-filtering IOL implantation. A clear interaction appears between the spectral power distribution and the spectral transmittance, depending on the visual task. Transparent ocular media allow benefiting from the greater short-wavelength content of the halide lamp. However, cataracts increase contrast threshold and visual reaction time values and also affects how the spectral power distribution influences these visual tasks. After surgery and intraocular lens implantation, visual performance improves for both lamps and the blue light-filter seems to influence spectral transmittance, which affects visual performance under light provided by greater short-wavelength content lamps. Cataract surgery is responsible for an improvement in contrast threshold and visual reaction time tasks, though blue light-filtering of the intraocular lens seems to prevent the visual system from benefiting from lamps with greater emission at short wavelengths.

Genetic diversity in developmental responses to light spectral quality in barley (Hordeum vulgare L.)

BackgroundPlants use light wavelength, intensity, direction and duration to predict imminent seasonal changes and to determine when to initiate physiological and developmental processes. Among them, crop responses to light are not fully understood. Here, we study how light quality affects barley development, using two broad-spectrum light sources, metal halide (M) and fluorescent (F) lamps. Eleven varieties with known allelic variants for the major flowering time genes were evaluated under controlled conditions (long days, same light intensity). Two experiments were carried out with fully-vernalized plants: 1) control treatments (M, F); 2) shifting chambers 10 days after the start of the experiment (MF, FM).ResultsIn general, varieties developed faster under longer exposure to M conditions. The greatest differences were due to a delay promoted by F light bulbs, especially in the time to first node appearance and until the onset of stem elongation. Yield related-traits as the number of seeds were also affected by the conditions experienced. However, not each variety responded equally, and they could be classified in insensitive and sensitive to light quality. Expression levels of flowering time genes HvVRN1, HvFT1 and PPD-H1 were high in M, while HvFT3 and HvVRN2 were higher under F conditions. The expression under shift treatments revealed also a high correlation between HvVRN1 and PPD-H1 transcript levels.ConclusionsThe characterization of light quality effects has highlighted the important influence of the spectrum on early developmental stages, affecting the moment of onset of stem elongation, and further consequences on the morphology of the plant and yield components. We suggest that light spectra control the vernalization and photoperiod genes probably through the regulation of upstream elements of signalling pathways. The players behind the different responses to light spectra found deserve further research, which could help to optimize breeding strategies.

Electrical Energy Conservation Aspects in Indian Railways

Indian Railways (IR) is the designated consumer of electricity in India. Railways utilize electrical energy to run railway on electric motors as well as for illumination of railway platforms, railway compartments, railway track, etc. Electricity in railways also utilized for railway traffic signalling. Electricity plays a very important role in Indian Railways. Indian Railways’ power demand is 2000 MW at present. Currently, there are only 60% of electrified railway tracks in India. The power requirement for 100% electrified broad gauge will increase from 2000 megawatts (MW) to 3400 MW. So, there is a need to reduce energy consumption by means of energy conservation. Formerly, the lighting systems used on railways are incandescent bulbs, fluorescent tubes, HPMV lamps, metal halide lamps and HPSV lamps. Lighting systems are one of the key areas of railway energy consumption. Today, LEDs are widely used for lighting in stations, service buildings, residential premises and more. This article gives a current condition, an initiative to reduce consumption, some energy conservation aspects in Indian Railways.

An energy saving potential analysis of lighting retrofit scenarios in outdoor lighting systems: A case study for a university campus

This study investigates the energy-saving potential and environmental effects of the whole outdoor lighting applications including the roads, footpaths and garden lights at Istiklal Campus of Burdur Mehmet Akif Ersoy University, Burdur, Turkey. 92% of the energy consumed for the outdoor lighting at the campus are used up by metal-halide lamps. Campus lighting is on automatically with the daylight sensor and operates for 10 h on average during the summer times and 13 h on average during the winter times. For this outdoor lighting system, energy-efficient lighting alternatives are investigated under four different scenarios. These scenarios are: shutting down some lamps 30 min after the education finishes at the campus; dimming for lamps; retrofitting the non-LED lights with effective LED lights and finally using the last two alternatives together. Next, potential energy-saving and the effects of this energy-saving on the environment are analyzed. According to the analysis results, a combination of retrofitting the lighting and dimming control systems are calculated to save 762 MWh electrical energy annually. With the reduced energy consumption, it is possible to cut down fossil fuels for electricity production and release 251 tons less carbon to the atmosphere annually. When the cost comparison is made for 12 years, it is predicted that about 1.3 million euros will be saved in the fourth scenario. Available traditional lighting systems in almost all of the cities in Turkey are inadequate in terms of energy efficiency. General lighting services constitute a significant part of the municipalities’ electricity costs in small cities. The scenarios proposed in this study can be applied by the municipalities on a city or neighborhood scale, taking into account criteria such as initial investment cost, energy savings, security, payback time and remote controllability & traceability.

Effects of Nozzle L/D on Near-Field Development and Macroscopic Spray Characteristics of Common-Rail Diesel Sprays

This study was performed to investigate the effects of L/D ratio of the nozzle on initial development and macroscopic spray behavior of diesel spray to understand the formation process of spray cone angle. Near-field and far-field spray visualization was performed for various injection pressures, and the effects of L/D ratio of the nozzle on spray cone angle were analyzed. A long-distance microscope and a CCD camera were used to obtain near-field spray images. Also, macroscopic spray development was evaluated using a high-speed camera and two metal halide lamps to compare the spray cone angle depending on L/D ratio. In the initial stage of injection, a laminar flow regime is observed, and downstream of the liquid column is deformed due to the large drag force of the surrounding gas. The area of the initial spray head, which has a small amount of momentum, becomes wider due to drag, and a strong eddy flow is formed around the deformed spray head. As the momentum of the supplied fuel increases over time, a mushroom-like structure is formed because momentum is continuously supplied at the center of the spray, while the outside of the spray head receives only drag force without providing additional momentum.

Effects of light quality and temperature on the photosynthesis and pigment content of a subtidal edible red alga Meristotheca papulosa (Solieriaceae, Gigartinales) from Japan

This study investigated the effects of different light spectral qualities and temperature on the photosynthesis and pigment content of a subtidal edible red alga, Meristotheca papulosa. Photosynthesis–irradiance (P–E) experiments were carried out under red (660 nm), blue (450 nm), green (525 nm, light-emitting diodes), and white light (visible light, metal halide lamp), and at 12, 20, and 28 °C, respectively. Maximum net photosynthetic rates (NPmax) were highest under green light. Other P–E parameter estimates were similar among algae under red, blue, and green light, including their lower initial slope (α) and higher saturation irradiances (Ek) as compared to those under white light. Additionally, NPmax and Ek under white light were highest at 28 °C, and lowest at 12 °C with characteristic photoinhibition at irradiances greater than 150 μmol photons m−2 s−1. Photosynthesis–temperature (P–T) experiment revealed that the maximum gross photosynthetic rate (GPmax) occurred at 22.1 °C, which was within the optimal temperature range of Fv/Fm (21.5–23.6 °C). Exposures to the different light qualities at 100 μmol photons m−2 s−1 for 7 days showed increased phycoerythrin (PE) concentration of algae under blue and green light, while chlorophyll-a and phycocyanin (PC) showed little variation in all light qualities. Therefore, considering future management prospects for M. papulosa mariculture, we suggest that green light could be utilized to enhance photosynthesis. Furthermore, if the aim is to achieve high PE content for an improved reddish-color fresh product, exposure to blue or green light could be a good alternative.

Mating success of the black soldier fly, Hermetia illucens (Diptera: Stratiomyidae), under four artificial light sources

Larvae of the black soldier fly (BSF) Hermetia illucens (L.) (Diptera: Stratiomyidae) are promising organisms to be used for organic waste bioconversion. Breeding BSF indoors has been suggested as a cost-effective approach for countries with long winters or low sunlight levels through the year. As the BSF mating is visually mediated, artificial illumination conditions are critical to a successful indoor breeding system. In this study, we tested four different types of artificial light sources for their effects on BSF mating success. They included: (1) a halogen lamp; (2) a combination of a white light-emitting diode (LED) lamp and a fluorescent ultra violet lamp; (3) a metal halide lamp, and (4) a specially designed light-emitting diode (BSFLED) lamp, whose design was based on the specific BSF adult visual spectral sensitivity. We determined the spectra of four artificial light sources, compared their spectral composition in relation to the BSF-visible spectrum, and compared their effects on the mating success of two different BSF colonies. BSFLED was the most energy efficient light source in spectral composition and led to the highest mating success in terms of the percentage of inseminated females and fertile clutches. Thus, BSFLED is the most suitable light source tested in our experiment for breeding BSF indoors. The colony effect and possible light flickering effect on BSF mating success were also detected. The implications of these findings are discussed.

Internal Cavitating Flow and External Spray Behavior Characteristics According to Length-to-Width Ratio of Transparent Nozzle Orifice

The purpose of this study is to investigate effects of length-to-width (L/W) ratio on cavitation flow inside a transparent acrylic nozzle orifice, and its effects on spray angle. Three visualization nozzles with different geometries (L/W = 2.0, 2.67, and 4.0) are used, and the working fluid is water. In order to visualize the development process of cavitation, the injection pressure of the working fluid is changed, and a high-speed camera is used with a metal-halide lamp. From experiments and analysis, some important facts are determined. As the injection pressure increases, the cavitation length and thickness increase linearly until the hydraulic flip occurs. Although the cavitation width varies according to the orifice width, the maximum cavitation thickness relative to the orifice width is almost constant at approximately 25% ∼ 30%. When the nozzle shape ratio increases, the discharge coefficient tends to increase because of the decrease in friction area. When entering the hydraulic flip region, the discharge coefficient decreases due to the reduction of the exit section area. The spray angle is affected by the cavitation number, cavitation length, cavitation thickness, and Reynolds number. The higher the injection pressure, the higher the turbulence intensity, and the greater the instability of the fluid flow.

Photocatalytic degradation of nitro‐aromatic explosives using visible‐light‐activated WO3: Optimization and catalyst modification

AbstractNitro‐aromatic explosives are hazardous, stable, and carcinogenic pollutants in industrial wastewaters. Photocatalytic degradation is one of the most efficient methods for the treatment of these types of pollutants. In this work, the degradation of p‐nitrophenol (PNP) as a typical nitro‐aromatic pollutant was studied using the synthesized catalyst WO3 under visible light irradiation. The synthesized catalyst was characterized using X‐ray diffraction, field‐emission scanning electron microscopy, and diffuse reflection spectroscopy. The effect of the operational parameters on the process efficiency, such as initial pH, initial concentration of PNP, catalyst dose, reaction temperature, calcination temperature (CT), and light source type, was studied. The effect of different morphologies of WO3 on the process efficiency was also evaluated. The results show that, under the optimum condition (pH = 11.5, catalyst dosage = 1000 μg/ml, and CT = 700°C) at T = 25°C and for initial PNP concentration of 20 μg/ml, the process can degrade and mineralize PNP by about 90% and 40.16%, respectively, after 240 min. Under the obtained optimum condition, mineralization of 2,4,6‐trinitrotoluene as a nitro‐aromatic explosive was evaluated, and 28% mineralization was observed after 240 min. The electrical energy consumption of the process was also assessed, and under the optimum condition, it was calculated as 602.3 and 94.0 kWh/m3 for the metal halide lamp and light‐emitting diode, respectively.

Preparation and Photocatalytic Property of Ag Modified Titanium Dioxide Exposed High Energy Crystal Plane (001)

TiO2 exposed high energy crystal plane (001) was prepared by the sol-gel process using butyl titanate as the titanium source and hydrofluoric acid as the surface control agent. Ag-TiO2 was prepared by depositing Ag on the crystal plane of TiO2 (101) with a metal halide lamp. The surface morphology, interplanar spacing, crystal phase composition, ultraviolet absorption band, element composition, and valence state of the samples were characterized by using field emission scanning electron microscopy (FESEM), transmission electron microscope (TEM), X-ray diffraction (XRD), ultraviolet-visible absorption spectrum (UV-Vis-Abs), and X-ray photoelectron spectroscopy (XPS), respectively. The formation mechanism of high energy crystal plane (001) was discussed, and the photocatalytic activities were evaluated by following degradation of methyl orange. The results show that TiO2 exposed the (001) crystal plane with a ratio of 41.8%, and Ag can be uniformly deposited on the crystal plane of TiO2 (101) by means of metal halide lamp deposition. Under the same conditions, the degradation rate of methyl orange by deposited Ag-TiO2 reaches as much as 93.63% after 60 min using the metal halide lamp (300 W) as an illuminant, 81.89% by non-deposited samples and 75.20% by nano-TiO2, causing a certain blue shift in the light absorption band edge of TiO2. Ag-TiO2 has the best photocatalytic performance at a pH value of 2.

Preparation and Photocatalytic Properties of CdS/F–TiO2 Composites

F–TiO2 was prepared by a simple precipitation method using titanium sulfate as the titanium source, hydrogen fluoride as the fluorine source and ammonia as the precipitant. CdS/F–TiO2 composites were prepared by hydrothermal synthesis of CdS and F–TiO2. The surface morphology, crystal phase composition, ultraviolet absorption band, fluorescence intensity, element composition, valence state, specific surface and pore structure of the samples were characterized by using field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), ultraviolet visible absorption spectrum (UV-Vis-Abs), Molecular fluorescence spectrophotometer (PL) and X-Ray photoelectron spectroscopy (XPS) and Surface area analyzer (BET), respectively. The effects of the dosage of the photocatalyst, pH value, the concentration of methyl orange and the addition of H2O2 on the photocatalytic performance were investigated with methyl orange solution as the target degradation product. The results showed the optimum condition for photodegradation of methyl orange by 1% CdS/F–TiO2 is that the pH value, the solid-liquid ratio, the concentration of methyl orange and the dosage of H2O2 is 2, 2 g/L, 10 mg/L and 3%, respectively. Under the same conditions, the degradation rate of methyl orange by 1% CdS/F–TiO2 was 93.36% when 300 W metal halide lamp was irradiated for 20 minutes, which was significantly higher than that of F–TiO2. CdS has a significant effect on the morphology, crystallinity, grain size and the compound probability of electrons and holes after the F–TiO2 modification. The composite causes a significant red shift at the edge of the F–TiO2 light absorption band. The photocatalytic degradation of methyl orange by 1% CdS/F–TiO2 follows the Langmuir-Hinshelwood first-order kinetic model.

Effect of light intensity on survival and photosynthetic efficiency of cultured corals of different ages

In this present study, we investigated the effects of increase and decrease of light intensity and photoperiods on growth, survival, and photosynthetic efficiency in three different corals, Pocillopora damicornis (Linnaeus, 1758), Acropora millepora (Ehrenberg, 1834) and Platygyra sinensis (Milne Edwards and Haime, 1849) with different ages (6-, 12-, and 24-month old). All experimented corals were cultured from sexual propagation. In light intensity trials, juvenile corals were transferred and exposed to different treatments (0, 21, 42, 85, and 169 μmol m−2 s−1 provided by 400-W metal halide lamps or equal to daily light integrals (DLI) of 0, 0.95, 1.89, 3.8, and 7.6 μmol m−2 s−1) for 2 weeks, while in the photoperiod experiment, the coral colonies were exposed to 5 different treatments (24/0, 18/6, 12/12, 6/18, and 0/24 h light-and-dark cycle). The results from the light intensity experiment showed that 2-year old Platygyra sinensis survived (100%) under all light intensity levels, while the survival rates of other coral species decreased, ranging between 20 and 80%, when the light intensity levels changed from the ambient light condition. For the photoperiod experiments, the results showed that 2-year old Platygyra sinensis and 1-year old Acropora millepora survived (100%) under all photoperiod levels. However, there was no significant difference on the growth of corals between different light intensity levels and different photoperiods. From this study, Platygyra sinensis seemed to have more tolerance to wider ranges of light intensities and photoperiods than other coral species. In addition, the results implied that corals were able to acclimate to a prolonged light period and light intensity, which can be feasible for future coral aquaculture.

Performance analysis of Light Emitting Diode, High Sodium Pressure and Metal Halide Lights

Light Emitting Diode (LED) lamps have been widely applied to street lighting in every country, but not a few still using conventional lamps like High Pressure Sodium (HPS) and Metal Halide (MH). This research presents the results of evaluating efficiency and photometric performance from street lighting lamps. The level of illumination and uniformity ratio will be calculated to make a quantitative comparison between LED lights and conventional lamps according to Indonesian National Standards. Research carried out on three different Street Lightings in Bandung with three different lights specification. Conditions in the field will be simulated using DIALux software. The results of this research are obtained that LED lamp is the most effective and efficient type of lamps compared with conventional lamps. This Research will be useful for the Public Works Agency in making decision on the selection of the new lamps technology for street lighting, determining the type of lamp should depends on needs and light quality.

High-Order Compensated Wireless Power Transfer for Dimmable Metal Halide Lamps

A high-order compensated wireless power transfer (WPT) system is proposed and implemented for dimmable metal halide (MH) lamps without using any ignitor or ballast. Possessing high ignition voltage and constant current output, the LCC - LC compensated WPT is identified to be more competent for MH lamps as compared with the four basic compensation networks as well as the double-sided LCC compensation networks. Meanwhile, dimming control and power stabilization are achieved by the phase-shift modulation, and the multilayer multitype coil is newly proposed to enhance the tolerance of varying coupling coefficients. For exemplification, a wireless dimmable MH lamp operating at 400 kHz has been designed and prototyped. Particularly, the system can tolerate coil deviation up to 20 cm and dim the lamp down to 30% of standard illuminance with the merit of acoustic resonance free. Both theoretical and experimental results are given to validate the feasibility of the proposed system.

Photocatalytic degradation of trimethoprim using S-TiO2 and Ru/WO3/ZrO2 immobilized on reusable fixed plates

In this study, photocatalytic degradation of trimethoprim by synthesized S-TiO2 and Ru/WO3/ZrO2 catalysts was investigated. Both photocatalysts have been immobilized on circular aluminum plates by polysiloxane to investigate their reusability performance. The morphology and structure of the catalysts were studied by high-resolution transmission electron microscopy, X-ray diffraction, and energy-dispersive X-ray spectroscopy. The photocatalytic experiments were carried out using suspended and attached catalysts using a metal halide lamp as a light source. The degradation efficiencies of trimethoprim were 100% and 98.2% at catalyst dose of 0.5 g/L, pH of 7.0 and irradiation time of 240 min using suspended Ru/WO3/ZrO2 and S-TiO2, respectively. After immobilization of the catalysts on the aluminum plates, the removal efficiencies in five repetitive cycles were 98%, 96.9%, 96.8%, 93.2% and 83.4% using Ru/WO3/ZrO2, while they were 88.6%, 86%, 84%, 78% and 75.9% in case of S-TiO2. The irradiation time of each cycle was 240 min, and the initial trimethoprim concentration was 10 mg/L. The degradation rates of trimethoprim were estimated in the case of suspended and immobilized S-TiO2 and Ru/WO3/ZrO2. The radical trapping experiments using various scavengers revealed that superoxide radicals, holes and hydroxyl radicals all participated in the photo-degradation process. Furthermore, the transformation products generated during the trimethoprim oxidation process were detected by liquid chromatography/mass spectroscopy to identify the possible degradation pathways.

Urban park lighting as a source of botanical light pollution

In this paper we are focusing on analysis of spectral power distribution (SPD) LED's lamp impact on botanical light pollution, described in relation to full moon light. We introduced new index RMPI which is called Photosynthesis Index in Relation to Moon. We found that in the case when lighting are realized by using LED luminaires instead of high pressure sodium (HPS) or metal halide (MH) lamps, light influence on plant vegetation process amplifies. Additionally our research shows that lamp's CCT is not a sufficient indicator of botanical light pollution and only SPD should be used for this purpose. Full Text: PDF ReferencesP. Tabaka, I. Fryc, Landscape Lighting as a Source of Light Pollution - the Effect of the Seasons on this Phenomenon, Lighting Conference of the Visegrad Countries, Lumen V4, 10.1109/LUMENV.2016.7745541 (IEEE 2016) CrossRef I. Fryc, F. Bisegna, P. Tabaka, Lighting on Recreation Grounds as a Source of Sky Glow - the Influence of Luminaire Type on this Phenomenon, Environment and Electrical Engineering and 2017 IEEE Industrial and Commercial Power Systems Europe (EEEIC / I&CPS Europe) 2017 IEEE International Conference, doi: 10.1109/EEEIC.2017.7977724, (IEEE 2017) CrossRef I. Fryc, P. Tabaka, Zanieczyszczenie Nocnego Nieboskłonu Światłem Emitowanym Przez Oprawy Oświetlenia Zewnętrznego, Przeglad Elektrotechniczny R. 93, No 6, doi: 10.15199/48.2017.06.1, (2017) CrossRef H.E. Schwarz, et al, Light Pollution: The Global View, ISBN 978-94-017-0125-9, (2003) DirectLink M. Aube, J. Roby, M. Kocifaj, Evaluating Potential Spectral Impacts of Various Artificial Lights on Melatonin Suppression, Photosynthesis, and Star Visibility, PLoS One CrossRef M. S. Sankhla, K. Sharma, R. Kumar, Impacts on Human & Environment of Night Time Galore International Journal of Applied Sciences and Humanities, Issue: 2; Vol. 3 (2019) CrossRef M. Tanaka, T. Horiuchi, S. Tominaga, Color Control of a Lighting System Using RGBW LEDs, Color Imaging XVI: Displaying, Processing, Hardcopy, and Applications, 78660W) CrossRef M. Mottus et al, Photosynthetically Active Radiation: Measurement and Modeling, Encyclopedia of Sustainability Science and Technology (2011) CrossRef J. Li, G. Li, H. Wang, X. W. Deng, "Phytochrome Signaling Mechanisms" The Arabidopsis Book Vol. 9, e0148 (2011) CrossRef J.B. Clark, G.R. Lister, Photosynthetic Action Spectra of Trees: I. Comparative Photosynthetic Action Spectra of One Deciduous and Four Coniferous Tree Species as Related to Photorespiration and Pigment Compements, Plant Physiol., NCBI 401-6 (1975) CrossRef DIN 5031-10, Optical radiation physics and illuminating engineering - Part 10: Photobiologically effective radiation, quantities, symbols and action spectra (2018) DirectLink C. ChiLing et al, Effect of Night Illumination on Growth and Yield of Soybean, Journal of Taiwan Agricultural Research, Vol.58 No.2, (2009) DirectLink J. Bennie et al, Ecological Effects of Artificial Light as Night on Wild Plants, Journal of Ecology, https://doi.org/10.1111/1365-2745.12551 (2016) CrossRef W.R. Chaney, Does Night Lighting Harm Trees? Circular FNR-FAQ-17 ( 2002) DirectLink

Synthesis of Fibrous Sm3+-Doped Titanium Dioxide Using Collagen Fiber As a Template and Its Photocatalytic Properties

Fibrous Sm3+-doped TiO2 (Sm/TiO2) was prepared using collagen fibers as a template. Samples were calcined at different temperatures to prepare TiO2 as well as Sm/TiO2, and effects of Sm-doping on crystallization, crystal transformation and grain size were investigated in detail. The morphology, crystalline structure, diffuse reflection spectrum and element chemical status of the products were characterized using scanning electron microscopy (SEM), X-ray diffractometer (XRD), ultraviolet visible spectrophotometry (UV–Vis DRS) and X-ray photoelectron spectroscopy (XPS), respectively. The photocatalytic performance was evaluated by the following degradation of methyl orange. The results show that the original fiber structure of collagen template is fully preserved when calcinations are carried out at 500–700°C. Sm-doping has an significant effect on crystallization and grain size of TiO2. After samarium doping, the band gap of sample decreased from 3.06 to 3.02 eV, the product has a significant red shift of optical absorption band edge, and the absorbance is also enhanced in visible region. The orbit component of O 1s for 4% Sm–TiO2 is shifted to a higher binding energy. The biggest enhancement in photocatalytic activity was obtained with a dopant amount of 4% samarium calcined at 600°C, and the degradation rate of methyl orange reaches 98.22% after 40 min using metal halide lamp (350 W) as illuminant, which is much higher than that of undoped one.

Optimal LED Filtering for Fluorescence Microscopy

Abstract

Solar radiation and the validity of infrared tympanic temperature during exercise in the heat.

We investigated the validity of infrared tympanic temperature (IR-Tty) during exercise in the heat with variations in solar radiation. Eight healthy males completed stationary cycling trials at 70% peak oxygen uptake until exhaustion in an environmental chamber maintained at 30°C with 50% relative humidity. Three solar radiation conditions, 0, 250 and 500W/m2, were tested using a ceiling-mounted solar simulator (metal-halide lamps) over a 3 × 2m irradiated area. IR-Tty and rectal temperature (Tre) were similar before and during exercise in each trial (P > 0.05). Spearman's rank correlation coefficient (rs) demonstrated very strong (250W/m2, rs = 0.87) and strong (0W/m2, rs = 0.73; 500W/m2, rs = 0.78) correlations between IR-Tty and Tre in all trials (P < 0.001). A Bland-Altman plot showed that mean differences (SD; 95% limits of agreement; root mean square error) between IR-Tty and Tre were - 0.11°C (0.46; - 1.00 to 0.78°C; 0.43 ± 0.16°C) in 0W/m2, - 0.13°C (0.32; - 0.77 to 0.50°C; 0.32 ± 0.10°C) in 250W/m2 and - 0.03°C (0.60; - 1.21 to 1.14°C; 0.46 ± 0.27°C) in 500W/m2. A positive correlation was found in 500W/m2 (rs = 0.51; P < 0.001) but not in 250W/m2 (rs = 0.04; P = 0.762) and 0W/m2 (rs = 0.04; P = 0.732), indicating a greater elevation in IR-Tty than Tre in 500W/m2. Percentage of target attainment within ± 0.3°C between IR-Tty and Tre was higher in 250W/m2 (100 ± 0%) than 0 (93 ± 7%) and 500 (90 ± 10%; P < 0.05) W/m2. IR-Tty is acceptable for core temperature monitoring during exercise in the heat when solar radiation is ≤ 500W/m2, and its accuracy increases when solar radiation is 250W/m2 under our study conditions.