We report here the observation of 16 µm superradiance laser action generated from optical pumping of CF4 gas molecules (which is cooled to 140 Kº by a boil-off liquid-N2) by a TEA-CO2 laser 9R12 line. Output laser pulses of 7 mJ and 200 ns have been obtained.
The technical of Flame Thermal Spray had been used in producing a cermet
composite based on powders of stabilized zirconium oxide containing amount of
Yatteria oxide (ZrO2- 8Y2O3) reiforced by minerals powders of bonding material
(Ni-Cr- Al- Y) in different rates of additions (25, 35, 50) on stainless steel base type
(304) after preparing it by the way of Grit Blasting.
Before heat treatment, the coated cermet layers were characterized for porosity
and electric resistivity. All samples were heat treated in vacuum furnace at different
temperature and times. The physical tests had been operated after heat treatment
and gave best results especially porosity, which found to be reduced dramatically
and producing hig
In this work, metal oxides nanostructures, mainly, copper oxide (CuO), nickel oxide (NiO), titanium dioxide (TiO2), and multilayer structure were synthesized by dc reactive magnetron sputtering technique. The structural purity and nanoparticle size of the prepared nanostructures were determined. The individual metal oxide samples (CuO, NiO and TiO2) showed high structural purity and minimum particle sizes of 34, 44, 61 nm, respectively. As well, the multilayer structure showed high structural purity as no elements or compounds other than the three oxides were founds in the final sample while the minimum particle size was 18 nm. This reduction in nanoparticle size can be considered as an advantage for the dc reactive magnetron sputtering tec
... Show MoreIn this work, a novel design for the NiO/TiO2 heterojunction solar cells is presented. Highly-pure nanopowders prepared by dc reactive magnetron sputtering technique were used to form the heterojunctions. The electrical characteristics of the proposed design were compared to those of a conventional thin film heterojunction design prepared by the same technique. A higher efficiency of 300% was achieved by the proposed design. This attempt can be considered as the first to fabricate solar cells from highly-pure nanopowders of two different semiconductors.
Background: Pilonidal sinus is a recurrence pathology that affects the gluteal area, cleft part of it. It affects many parts but mainly the sacral area and may present with various forms; from the asymptomatic cyst to severe infection in a form of painful abscess or sinus. The treatment of pilonidal sinus ranges from observation with good hygiene to excision of the sinus left wide incision. Recurrence may follow the excisional procedure and may need more operations. Many conservative ways had been used for the management of the sinus; laser (phototherapy) is one kind that may use. this paper aims to test the efficiency of the laser (diode 980nm) in the treatment of the sinus. material:
... Show MoreNanoparticle has pulled in expanding consideration with the developing enthusiasm for nanotechnology which hold potential as essential segments for development applications. In the present work, a copper nanoparticle is manufactured as a suspension in distilled water by beating a bulk copper target with laser source (532 nm wavelength, 10 ns pulse duration and 10 Hz repletion rate) via method. UV- visible absorption spectra and AFM analysis has been done to observe the effect of repetition rate for the pulsation of laser. Copper nanoparticles (Cu-NPs) were successfully synthesized with green color. The Cu- NPs have very high purity because the preparation was managed in aqueous media to eliminate ambient contaminations. Absorption
... Show MoreThe present work was done in an attempt to build systematic procedures for treating warts by 810 nm diode laser regarding dose parameters, application parameters and laser safety. The study was done in Al- Kindy Teaching Hospital in Baghdad, Iraq during the period from 1st October 2003 till 1st April 2004. Fifteen patients completed the treatment and they were followed for the period of 3 months. Recalcitrant and extensive warts were selected for the study. Patients were randomly divided into 3 groups to be treated by different laser powers 9, 12 and 15 W, power density of 286 W/cm2, 381W/cm2, 477 W/cm2 pulse duration of 0.2 s, interval of 0.2 s and repeated pulses were used. The mode of application was either circular or radial. Pain oc
... Show MoreThis research aims to design a high-speed laser diode driver and photodetector, the result is the
design of the high-speed laser diode driver with a short pulse of 10 ns at 30 KHz frequency and the
delivered maximum pulse voltage is 5.5 mV. Also, its optical output power of the laser diode driver is
about 2.529 mW for the centroied wavelength 1546.7 nm with FWHM of 286 pm and (1270-1610) nm.
The design of the circuit based on bipolar transistor where the input pulse signal is simply generated by
an arduino kit with 15 kHz frequency and then compensated to trigger to small signal amplifier which
was is simply NPN C3355 transistor and the output is a current driver to the laser diode. OptiSystem
software and Electronic
Activated carbon prepared from date stones by chemical activation with ferric chloride (FAC) was used an adsorbent to remove phenolic compounds such as phenol (Ph) and p-nitro phenol (PNPh) from aqueous solutions. The influence of process variables represented by solution pH value (2-12), adsorbent to adsorbate weight ratio (0.2-1.8), and contact time (30-150 min) on removal percentage and adsorbed amount of Ph and PNPh onto FAC was studied. For PNPh adsorption,( 97.43 %) maximum removal percentage and (48.71 mg/g) adsorbed amount was achieved at (5) solution pH,( 1) adsorbent to adsorbate weight ratio, and (90 min) contact time. While for Ph adsorption, at (4) solution pH, (1.4) absorbent to adsorbate weight ratio, and (120 min) contact
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