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Author(s):  
Daniel Wendler ◽  
Ralph Dux ◽  
Rainer Fischer ◽  
Michael Griener ◽  
Elisabeth Wolfrum ◽  
...  

Abstract The thermal helium beam diagnostic at ASDEX Upgrade is used to infer the electron density ne and temperature Te in the scrape-off layer and the pedestal region from the emission of visible lines of the locally injected helium. The link between ne and Te and the emission is provided by a collisional radiative model, which delivers the evolution of the populations of the relevant excited states as the He atoms travel through the plasma. A computationally efficient method with just three effective states is shown to provide a good approximation of the population dynamics. It removes an artificial rise of Te at the plasma edge when using a simple static model. Furthermore, the re-absorption of the vacuum ultra-violet resonance lines has been introduced as additional excitation mechanism being mainly important in the region close to the injection point. This extra excitation leads to a much better fit of the measured line ratios in this region for larger puff rates.


2022 ◽  
Author(s):  
Venkatesh D ◽  
Pavalamalar S ◽  
Silambarasan R ◽  
Anbalagan K

Abstract The photocatalytic activity of well-fabricated, economical SnO2/TiO2 nanocomposite synthesized via hydrothermal route was validated using the (NH3-trz)[Fe(dipic)2] complex under ultra-violet illumination. The structural features of (NH3-trz)[Fe(dipic)2] complex was explored in detail. The catalysts were systematically examined with XRD, SEM, FT-IR UV-vis, PL, micro-Raman, VSM, AFM, HRTEM. The photoreactivity of the model compound (NH3-trz)[Fe(dipic)2] in water/binary solvent systems was investigated. The rate of photoreaction (k) of nanocomposite (0.1432 sec-1) is higher than the SnO2 (0.0373 sec-1) and TiO2 (0.1422 sec-1) in H2O:PriOH (70:30%) than the rest of the solvents system. The pathways, mechanistic feature of accumulated reactive species on nanocomposite to induce adherent [Fe(dipic)2]- anion and photo-reductive products were studied. The generation of hydroxyl radical on the surface of each catalyst can be identified as 7-hydroxycoumarin and discussed.


2022 ◽  
Author(s):  
Andrew Cassidy ◽  
Rachel L. James ◽  
Anita Dawes ◽  
David Field

An exciton gives rise to an absorption peak in vacuum ultra-violet spectroscopy of solid ammonia, with time-resolved evolution of the peak revealing the rate of nucleation and phase change.


2022 ◽  
Vol 123 ◽  
pp. 111920
Author(s):  
Yiheng Ping ◽  
Lei Lei ◽  
Peng Qiao ◽  
Jun Zheng ◽  
Shixu Tao ◽  
...  
Keyword(s):  

2022 ◽  
Author(s):  
Prasenjit Prasad Sukul ◽  
Kaushal Kumar ◽  
Hendrik Christoffel Swart

Borate oxyfluoride glasses are transparent in the infra-red, ultra violet and visible regions and represent an ideal host matrix for optically active dopants. Due to their lower phonon energies compared...


2021 ◽  
Vol 27 (6) ◽  
pp. 1453-1460
Author(s):  
Da-Yeon Hong ◽  
Min-Ju Kim ◽  
Young-Jin So

In this study, natural motifs were extracted based on the trend colors selected by Pantone in 2018-2021, and the image was shaped to produce hair design works that reflected the trend colors. In Artwork I, the ultra violet color has a wisteria motif, and the hair color is expressed using the ombré technique. Artwork II Living Coral color has a coral reef in the sea as a motif, and the hair color is expressed in a two-tone technique. Artwork III Classic blue color has a blue zebra-patterned seashell as a motif, and hair color is expressed using weaving and balayage techniques. Artwork IV Illuminating and Ultimate Gray color are inspired by autumn birch trees, and hair color is expressed using weaving and two-tone techniques. In this way, it was confirmed that creative and diverse design expressions are possible by completing trendy hairstyles with various techniques by incorporating each Pantone color into nature.


Author(s):  
Md Mizanur Rahman ◽  
◽  
Bidhan Chandra Nath ◽  
Subrato Paul ◽  
Md. Golam Kibria Bhuiyan ◽  
...  

This research intends to design, assemble and evaluate the performance of an eco-friendly solar light trap to reduce the insect population in rice fields as well as to minimize the use of harmful chemical pesticides. An AutoCAD drawing tool 2016 was used to sketch the design of solar light trap. The main component of this light trap was bulb, solar panel and battery. Design of solar panel and battery was done considering by 5W LED bulb. A total of five bulbs with different colors were selected to test the insect’s reaction by visible light. Study indicated that ultra violet-blue bulb showed the best performance compare to others based on the high percentage of insect trap (31.22%). A 20-watt solar panel and two 4.5 ah batteries of 6 volts were used to operate the solar light trap. The current, voltage, solar intensity was recorded to check overall performance of solar panel. The solar panel generated more power in April than May due to higher solar radiation in the study area. Study suggested that only 4.26 sunshine hours were required to full charge the battery. The solar light trap was operated 5.5 hour in night which was sufficient to reduce the insects in rice field. Moreover, the light sensor was showed 100% functional for ON/OFF purposes. The dominant insects like yellow stem borer (YSB), green leafhopper (GLH) were mostly observed. The average largest numbers of YSB and GLH were 900 and 600 respectively. In conclusion, the solar light trap is eco-friendly, low cost, easy and self-sufficient in term of solar energy. Finally, the newly developed light trap could be helpful for manufactures, decision makers, and engineering community as well as farmers as a best tool to protect nature in comparison to other pesticide using practices.


2021 ◽  
Vol 24 (02) ◽  
Author(s):  
Rizana Azees ◽  
Asitha T. Cooray ◽  
K.G.U.R. Kumarasinghe

Cobalt (Co2+) is an essential constituent in the human body while excessive exposure leads to severe systemic toxic reactions which highlight the importance of developing effective methods to detect Co2+ ions. A simple and highly efficient fluorescence enhanced turn OFF-ON chemosensor was synthesized to detect the paramagnetic Co2+. The ligand, N-((1H-indol-3-yl)(phenyl)methyl)aniline (L), was synthesized in 92% yield by means of hydrated ferric chloride catalyzed one -pot multicomponent microwave irradiation in the presence of Indole, benzaldehyde, and aniline as reactants. The major green principles of waste prevention, high atom economy (94.3%), green solvent, higher energy efficiency, and catalysis were the highlights of the ligand synthesis. The ligand exhibited remarkable fluorescence enhancement with Co2+ and a turn ON ratio of over 160-fold in MeOH/H2O (at pH 3.5) solution at an excitation wavelength of 369 nm in the Ultra-Violet range. The detection limit of L- Co2+ was 2.2 μM. The excitation and the emission spectra indicated stoke’s shift of 93 nm which supports the fluorescence enhancement observed in L- Co2+ with respect to the free ligand. The Job’s plot indicated fluorometric sensing of Co2+ ascribed to the complex formation with a stoichiometric ratio of 2:1 (L- Co2+). Furthermore, the high linearity (r2 =0.992) observed in the Benesi Hildebrand plot in a wide concentration range of 0.5−80 μM confirmed the above stoichiometric ratio. The association constant (Ka) for the L-Co2+ was determined to be 8.382 ×1 04 M−1 ± 5.8 ×103M−1.The prepared Co2+ fluorometric probe indicated long-term stability in −18 ℃ up to 45 days. Furthermore, the presence of Fe2+ and Fe3+ in the medium with Co2+ exhibited an interference effect in the fluorescence intensities. Upon further concentration studies, it was evident that the interference of Fe2+ and Fe3+ starts around 10.00 μM and rises exponentially. Keywords: MCR, Green synthesis, Fluorescent Chemo-sensor, Turn OFF-ON, Cobalt (II), indole derivatives


2021 ◽  
Vol 37 (6) ◽  
pp. 1447-1451
Author(s):  
Arpita Biswas

Synthesis of Zincoxide nanoparticles (ZnO NPs) with definite size and shape and their morphological characterization rationally is really a challenging aspect at present due to the ongoing demand of these nanosize particles for their divergent use in different field of science and technology. Reduction of Zinc acetate dihydrate by sodium hydroxide was performed to produce ZnO NPs by following precipitation method. Here the whole reaction was completed in aqueous medium in low temperature. To characterize the synthesized ZnO NPs some recent techniques like X-Ray diffraction study (XRD), Ultra-Violet Visible (UV-Vis) spectroscopy, Field emission scanning electron microscopy (FESEM), Transmission electron microscopy (TEM), Selected area electron diffraction (SAED) and Electron diffraction X-ray (EDX) were used systematically.


INDIAN DRUGS ◽  
2021 ◽  
Vol 58 (11) ◽  
pp. 7-17
Author(s):  
Goutam K. Jena ◽  
Chinam N. Patra ◽  

Skin carcinoma is a frequently occurring cancer caused due to ultra violet rays of the Sun. It starts from normal skin cells but later on transforms into cells which undergo uncontrolled mitosis. Skin cancer is not as deadly as other cancers and has no metastasis and is not life threatening. Conventional chemotherapy has in general failed to treat skin cancer due to non specific targeting, which is accompanied by several side effects. Novel therapeutic approach based on nanotechnology have emerged as the best alternative for skin cancer treatment. We presented current scenario of nano based particulate drug carrier approaches for effective therapy for skin carcinoma by reducing side effects. This approach also reduces frequency of administration and improves patient compliance. Nanotechnology has emerged as the best alternative for conventional therapy for the effective treatment of skin cancer. Nanoparticles can specifically target skin carcinoma and are able to sustain drug release and reduce side effects to a greater extent.


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