Nd:YAG laser pulses of 9 nanosecond pulse duration and operating wavelength at 1.06 μm, were utilized to drill high thermal conductivity and high reflectivity aluminum and copper foils. The results showed a dependence of drilled holes characteristics on laser power density and the number of laser pulses used. Drilled depth of 74 ϻm was obtained in aluminum at 11.036×108 W/cm2 of laser power density. Due to its higher melting point, copper required higher laser power density and/or larger number of laser pulses to melt, and a maximum depth of 25 μm was reached at 13.46×108 W/cm2 using single laser pulse.
Breast mass is by far the most important clinical problem that concerns the breast today. This study was carried out to evaluate diode laser as a cutting tool in breast mass excision and as a hemostatic tool for coagulation during surgery. Using 810 nm diode laser with optical fiber 600μm in diameter of conical tip, udder (cow's breast) tissue, and three female patients (mean age of 35.5 y with clinically palpable breast mass) had been used in this study. The patients were followed up regularly postoperatively. In preliminary work on udder tissue, the power needed for cutting and excision was 15W (power density= 5.3 kW/cm2). The time consumed for excision of a piece of udder tissue, 40×10×3 mm in dimensions was 5 min. The depth range
... Show MoreOne of the troublesome duties in chemical industrial units is determining the instantaneous drop size distribution, which is created between two immiscible liquids within such units. In this work a complete system for measuring instantaneous droplet size is constructed. It consists of laser detection system (1mW He-Ne laser), drop generation system (turbine mixer unit), and microphotography system. Two immiscible liquids, water and kerosene were mixed together with different low volume fractions (0.0025, 0.02) of kerosene (as a dispersed phase) in water (as a continuous phase). The experiments were carried out at different rotational speed (1180- 2090 r.p.m) of the turbine mixer. The Sauter mean diameter of the drops was determined by la
... Show MorePyogenic granuloma is one of the inflammatory hyperplasia seen in the oral cavity. The
present study included 10 patients with pyogenic granuloma, involving 4 males and 6 females with 1:1.5
male to female ratio. Patient ages ranged from 5 to 85 years (mean, 30 years) and half of the lesions had
pedunculated base, with surface ulceration in 10% of cases. Treatment consisted of resection, using 810
nm diode lasers. Eight patients were anesthetized during the surgical operation by local infiltration of
anesthesia. Only three patients reported mild post-operative pain within the first 24 hours of the healing
period. During the surgical operation there was no significant bleeding so clear surgical field. There was
no blee
Pyogenic granuloma is one of the inflammatory hyperplasia seen in the oral cavity. The
present study included 10 patients with pyogenic granuloma, involving 4 males and 6 females with 1:1.5
male to female ratio. Patient ages ranged from 5 to 85 years (mean, 30 years) and half of the lesions had
pedunculated base, with surface ulceration in 10% of cases. Treatment consisted of resection, using 810
nm diode lasers. Eight patients were anesthetized during the surgical operation by local infiltration of
anesthesia. Only three patients reported mild post-operative pain within the first 24 hours of the healing
period. During the surgical operation there was no significant bleeding so clear surgical field. There was
no blee
The Optical Fiber sensor based on the Surface Plasmon Resonance (SPR) technology has
been a successful performance sensing and presents high sensitivity. This thesis investigates the
performance of several structure of SPR sensor in field of refractive index and chemical
applications. A structure of Multi-Mode Fiber- Single Mode Fiber- Multi Mode Fiber (MMFSMF-MMF)
Porous silicon (P-Si) has been produced in this work by photoelectrochemical (PEC) etching process. The irradiation has been achieved using diode laser of (2 W) power and 810 nm wavelength. The influence of various irradiation times on the properties of P-Si material such as P-Si layer thickness, surface aspect, pore diameter and the thickness of walls between pores as well as porosity and etching rate was investigated by depending on the scanning electron micrograph (SEM) technique and gravimetric measurements.
Semiconductor laser is used in processing many issues related to the scientific, military, medical, industrial and agricultural fields due to its unique properties such as coherence and high strength where GaN-based components are the most efficient in this field. Current technological developments mention to the strong connection of GaN with sustainable electronic and optoelectronic devices which have high-efficiency. The threshold current density of Al0.1Ga0.9N/GaN triple quantum well laser structure was investigated to determine best values of the parameters affecting the threshold current density that are well width, average thickness of active region, cavity length, reflectivity of cavity mirrors and optical confinement factor. The opt
... Show MoreFluorescence excitation by Nd:YAG pumped dye laser and single vibrational level fluorescence
spectra of 1,3 benzodioxole in a supersonic jet have been obtained and interpreted. The previous assignment of
the 0 0
0 band was incorrect. In addition, many other bands involving n20 and n19 vibrations of a2 symmetry were
confirmed. As far as a1 totally symmetric vibration is concerned. The n14 was assigned to be located in the fivemembered
ring whereas n13 seem to be located in the benzene ring as a result of the electronic transition in the
benzene ring which affects n13 and not n14 wavenumber.
Verrucae vulgares are commonly encountered. The present work is designed in an attempt to build a systematic procedure for treating warts by carbon dioxide laser regarding dose parameters, application parameters and laser safety.
Patients and Methods: The study done in the department of dermatology in Al-Najaf Teaching Hospital in Najaf, Iraq. Forty-two patients completed the study and follow up period for 3 months. Recalcitrant and extensive warts were selected to enter the study. Carbon dioxide laser in a continuous mode, in non-contact application, with 1 mm spot size was used. The patients were divided into two groups. The first group of patients consisted of 60 lesions divided to 6 equal groups, in whom we use different outputs a