69 research outputs found
Synthesis of blue-shifted luminescent colloidal GaN nanocrystals through femtosecond pulsed laser ablation in organic solution
We demonstrate the synthesis of GaN nanocrystals (NCs) with the sizes of less than the doubled exciton Bohr radius leading quantum confinement effects via a single-step technique. The generation of colloidal GaN nanoparticles (NPs) in organic solution through nanosecond (ns) and femtosecond (fs) pulsed laser ablation (PLA) of GaN powder was carried out. Ns PLA in ethanol and polymer matrix resulted in amorphous GaN-NPs with the size distribution of 12.4 ± 7.0 and 6.4 ± 2.3 nm, respectively, whereas fs PLA in ethanol produced colloidal GaN-NCs with spherical shape within 4.2 ± 1.9 nm particle size distribution. XRD and selected area electron diffraction analysis of the product via fs PLA revealed that GaN-NCs are in wurtzite structure. Moreover, X-ray photoelectron spectroscopy measurements also confirm the presence of GaN nanomaterials. The colloidal GaN-NCs solution exhibits strong blue shift in the absorption spectrum compared to that of the GaN-NPs via ns PLA in ethanol. Furthermore, the photoluminescence emission behavior of fs PLA-generated GaN-NCs in the 295–400 nm wavelength range is observed with a peak position located at 305 nm showing a strong blue shift with respect to the bulk GaN. © 2016, Springer Science+Business Media Dordrecht
Thin film MoS2 nanocrystal based ultraviolet photodetector
We report on the development of UV range photodetector based on molybdenum disulfide nanocrystals (MoS2-NCs). The inorganic MoS2- NCs are produced by pulsed laser ablation technique in deionized water and the colloidal MoS2-NCs are characterized by transmission electron microscopy, Raman spectroscopy, X-ray diffraction and UV/VIS absorption measurements. The photoresponse studies indicate that the fabricated MoS 2- NCs photodetector (MoS2-NCs PD) operates well within 300-400 nm UV range, with diminishing response at visible wavelengths, due to the MoS2- NCs absorption characteristics. The structural and the optical properties of laser generated MoS2-NCs suggest promising applications in the field of photonics and optoelectronics. © 2012 Optical Society of America
The phase diagram of three-flavor quark matter under compact star constraints
The phase diagram of three-flavor quark matter under compact star constraints
is investigated within a Nambu--Jona-Lasinio model. Local color and electric
charge neutrality is imposed for beta-equilibrated superconducting quark
matter. The constituent quark masses and the diquark condensates are determined
selfconsistently in the plane of temperature and quark chemical potential. Both
strong and intermediate diquark coupling strengths are considered. We show that
in both cases, gapless superconducting phases do not occur at temperatures
relevant for compact star evolution, i.e., below T ~ 50 MeV. The stability and
stucture of isothermal quark star configurations are evaluated. For
intermediate coupling, quark stars are composed of a mixed phase of normal (NQ)
and two-flavor superconducting (2SC) quark matter up to a maximum mass of 1.21
M_sun. At higher central densities, a phase transition to the three-flavor
color flavor locked (CFL) phase occurs and the configurations become unstable.
For the strong diquark coupling we find stable stars in the 2SC phase, with
masses up to 1.326 M_sun. A second family of more compact configurations
(twins) with a CFL quark matter core and a 2SC shell is also found to be
stable. The twins have masses in the range 1.301 ... 1.326 M_sun. We consider
also hot isothermal configurations at temperature T=40 MeV. When the hot
maximum mass configuration cools down, due to emission of photons and
neutrinos, a mass defect of 0.1 M_sun occurs and two final state configurations
are possible.Comment: 12 pages, 11 figure
Thermal decomposition and gasification of biomass pyrolysis gases using a hot bed of waste derived pyrolysis char
Chars produced from the pyrolysis of different waste materials have been investigated in terms of their use as a catalyst for the catalytic cracking of biomass pyrolysis gases during the two-stage pyrolysis-gasification of biomass. The chars were produced from the pyrolysis of waste tyres, refused derived fuel and biomass in the form of date stones. The results showed that the hydrocarbon tar yields decreased significantly with all the char materials used in comparison to the non-char catalytic experiments. For example, at a cracking temperature of 800 °C, the total product hydrocarbon tar yield decreased by 70% with tyre char, 50% with RDF char and 9% with biomass date stones char compared to that without char. There was a consequent increase in total gas yield. Analysis of the tar composition showed that the content of phenolic compounds decreased and polycyclic aromatic hydrocarbons increased in the product tar at higher char temperatures
Interpratation and adaptation of dermoscopic terminology to our language: Consensus report of the Turkish society of dermatology dermoscopy working group
"Dermoscopic Terminology Consensus Meeting" was held at Ege University Medical Faculty Dermatology Department on the 24th of February in 2012 with the aim of establishing a common language in the translation of the dermoscopic terminology in English literature into Turkish. In this article, the Turkish terminology in which the consensus was reached at that meeting is presented together with the definitions and representative images as a dictionary. © 2013 by Turkish Society of Dermatology
CRUSE®—An innovative mobile application for patient monitoring and management in chronic spontaneous urticaria
Background: Chronic spontaneous urticaria (CSU) is unpredictable and can severely impair patients' quality of life. Patients with CSU need a convenient, user-friendly platform to complete patient-reported outcome measures (PROMs) on their mobile devices. CRUSE®, the Chronic Urticaria Self Evaluation app, aims to address this unmet need. Methods: CRUSE® was developed by an international steering committee of urticaria specialists. Priorities for the app based on recent findings in CSU were defined to allow patients to track and record their symptoms and medication use over time and send photographs. The CRUSE® app collects patient data such as age, sex, disease onset, triggers, medication, and CSU characteristics that can be sent securely to physicians, providing real-time insights. Additionally, CRUSE® contains PROMs to assess disease activity and control, which are individualised to patient profiles and clinical manifestations. Results: CRUSE® was launched in Germany in March 2022 and is now available for free in 17 countries. It is adapted to the local language and displays a country-specific list of available urticaria medications. English and Ukrainian versions are available worldwide. From July 2022 to June 2023, 25,710 observations were documented by 2540 users; 72.7% were females, with a mean age of 39.6 years. At baseline, 93.7% and 51.3% of users had wheals and angioedema, respectively. Second-generation antihistamines were used in 74.0% of days. Conclusions: The initial data from CRUSE® show the wide use and utility of effectively tracking patients' disease activity and control, paving the way for personalised CSU management
Effects of chlorhexidine and gaseous ozone on microleakage and on the bond strength of dentin bonding agents with compomer restoration on primary teeth
Background/purpose: The aim of this study was to evaluate microleakage and bond strength in primary tooth dentin after disinfection with chlorhexidine solution or gaseous ozone.
Materials and methods: Sixty primary first and second molar teeth without caries were collected. Thirty of these teeth were ground to expose the dentin surface and divided into three groups (n = 10 for each group). After the application of materials, the teeth were restored with compomer restorations. Dentin sticks were obtained from these specimens and used for the microtensile bond strength test. The effect on the microleakage of the same materials of compomer restorations was then tested. class V cavities were prepared on the facial surfaces of the remaining 30 sound primary first and second molars to which the materials were applied and that were restored with compomer. The teeth were thermocycled, stained with basic fuchsine, sectioned for microleakage evaluation, and examined under a stereomicroscope. Kruskall-Wallis, Mann-Whitney U, one-way ANOVA, and post hoc Tukey tests were used for statistical analyses.
Results: When the bond strength of the groups were compared, the difference between the ozone group and the control group was not significant (P > 0.05); however, the difference between the chlorhexidine group and either of the other two groups was significant (P < 0.05). The chlorhexidine group of teeth showed the lowest bond strength rates. When the occlusal and gingival microleakage rates among the groups were compared, the difference was insignificant (P > 0.05).
Conclusion: Ozone application may be an alternative antibacterial procedure because the bond strength increased after ozone application. Chlorhexidine decreased bonding significantly. There was no significant difference between the microleakage values
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