BACKGROUND This case of gestational gingival tumor is huge and extremely rare in clinical practice.As the growth location of this gingival tumor is in the upper anterior tooth area,it seriously affects the pregnant wo...BACKGROUND This case of gestational gingival tumor is huge and extremely rare in clinical practice.As the growth location of this gingival tumor is in the upper anterior tooth area,it seriously affects the pregnant woman's speech and food,causing great pain to the patient.The use of Nd:YGA water mist laser to remove the gingival tumor resulted in minimal intraoperative bleeding,minimal adverse reactions,and good postoperative healing,which is worthy of clinical promotion and application.CASE SUMMARY The patient,a pregnant woman,reported a large lump in her mouth on the first day of postpartum treatment.Based on medical history and clinical examination,the diagnosis was diagnosed as gestational gingival tumor.Postoperative pathological biopsy also confirmed this diagnosis.The use of Nd:YAG water mist laser to remove the tumor resulted in minimal intraoperative bleeding,clear surgical field of view,short surgical time,and good postoperative healing.CONCLUSION In comparison to traditional surgery,Nd:YAG water mist laser surgery is minimally invasive,minimizes cell damage,reduces bleeding,ensures a clear field of vision,and virtually eliminates postoperative edema,carbonization,and the risk of cross infection.It has unique advantages in oral soft tissue surgery for pregnant patients.Therefore,the clinical application of Nd:YAG water mist laser for the treatment of gestational gingival tumors is an ideal choice.展开更多
A multipulse Nd:YAG (Neodym-yttrium aluminium garnet) laser Thomson scattering diagnostic system developed was recently applied on HT-7 tokamak to obtain more accurate electron temperatures. A CAMAC-based real-time...A multipulse Nd:YAG (Neodym-yttrium aluminium garnet) laser Thomson scattering diagnostic system developed was recently applied on HT-7 tokamak to obtain more accurate electron temperatures. A CAMAC-based real-time computer system for laser control, data acquisition, analysis and calibration was investigated in detail. Furthermore, the reliability and accuracy of this diagnostic system were demonstrated by comparing the results with those of a soft-X ray diagnostic system.展开更多
A pulsed Nd:YAG (yttrium aluminum garnet) laser-based technique was employed to clad low silicon steel with preplaced Si and Fe mixed powders for high Si content. The surface morphology, microstructural evolution, ...A pulsed Nd:YAG (yttrium aluminum garnet) laser-based technique was employed to clad low silicon steel with preplaced Si and Fe mixed powders for high Si content. The surface morphology, microstructural evolution, phase composition, and Si distribution, within the obtained cladding coatings, were characterized by optical microscopy (OM), field emission scanning electron microscopy (FE-SEM), with associated energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM), and X-ray diffraction (XRD). The microhardness was also measured along the depth direction of the specimens, A crack- and pore-free cladding coating through excellent metallurgical bonding with the substrate was successfully prepared on low silicon steel by means of optimized single-track and multi-track laser cladding. The phases of the coating are a-Fe, T-Fe, and FeSi. The high microhardness of the lasercladding zone is considered as an increase in Si content and as the refined microstructure produced by the laser treatment. The Si contents of the cladding coatings were about 5.8wt% in the single-track cladding and 6.5wt% in the multi-track cladding, respectively.展开更多
We report the specification of a compact and stable side diode-pumped Q-switched pulsed Nd:YAG laser. We ex- perimentally study and compare the performance of the pulsed Nd:YAG laser in the free-running and Q-switch...We report the specification of a compact and stable side diode-pumped Q-switched pulsed Nd:YAG laser. We ex- perimentally study and compare the performance of the pulsed Nd:YAG laser in the free-running and Q-switched modes at different pulse repetition rates from 1 Hz to 100 Hz. The laser output energy is stabilized by using a special configu- ration of the optical resonator. In this laser, an unsymmetrical concave-concave resonator is used and this structure helps the mode volume to be nearly fixed when the pulse repetition rate is increased. According to the experimental results in the Q-switched operation, the laser output energy is nearly constant around 70 mJ with an FWHM pulse width of 7 ns at 100 Hz. The optical-to-optical conversion efficiency in the Q-switched regime is 17.5%.展开更多
Laser transformation hardening (LTH) was applied to the surface of the AISI 420 martensitic stainless steel by a pulsed Nd:YAG laser to obtain optimum hardness. The influences of process parameters (laser pulse en...Laser transformation hardening (LTH) was applied to the surface of the AISI 420 martensitic stainless steel by a pulsed Nd:YAG laser to obtain optimum hardness. The influences of process parameters (laser pulse energy, duration time, and travel speed) on the depth and hardness of laser treated area were investigated. Image analysis of SEM microstructure of AISI 420 showed that plate-like carbide have almost fully and (30-40)% of globular carbide particles dissolved into the matrix after laser transformation hardening by pulsed laser and the microstructure was refined to obtain controlled tempered martensite microstructure with 450 VHN hardness.展开更多
The influence of pumping laser pulse on the property of quasi-continuous-wave(QCW)diode-side-pumped Nd:YAG laser is investigated theoretically and experimentally.Under remaining a fixed duty cycle,the average output p...The influence of pumping laser pulse on the property of quasi-continuous-wave(QCW)diode-side-pumped Nd:YAG laser is investigated theoretically and experimentally.Under remaining a fixed duty cycle,the average output power increases,and the corresponding thermal focal length shorten with the increase of the pump pulse duration,which attributes to the decrease of the ratio of pulse buildup time to the pulse duration.At a pump power of 146 W,the laser output power changes from 65.1 W to 81.2 W when the pulse duration is adjusted from 150μs to 1000μs,confirming a significant enhancement of 24.7%.A laser rate equation model incorporating the amplified spontaneous emission is also utilized and numerically solved,and the simulated results agree well with the experimental data.展开更多
A hybrid-pumped Nd:YAG pulse laser with a double-pass two-rod configuration is presented. The focal length of offset lens is particularly studied to compensate for the thermal lens effect and depolarization. For inpu...A hybrid-pumped Nd:YAG pulse laser with a double-pass two-rod configuration is presented. The focal length of offset lens is particularly studied to compensate for the thermal lens effect and depolarization. For input pulse energy of 141 μJ with pulse duration of 754ps, the pulse laser system delivers 526mJ pulse energy and 728ps pulse width output at lO Hz with pulse profile shape preservation. The energy stability of the laser pulse is less than 3%, and the beam quality factor M2 is less than 2.26.展开更多
Ce3+, Yb3+ co-doped Y3Al5O12 films were prepared by pulse laser deposition. X-ray diffraction, X-ray photoelectron spectroscopy, photoluminescence spectra were used to characterize their structural and luminescent p...Ce3+, Yb3+ co-doped Y3Al5O12 films were prepared by pulse laser deposition. X-ray diffraction, X-ray photoelectron spectroscopy, photoluminescence spectra were used to characterize their structural and luminescent properties. Near-infrared quantum cutting from the films was observed via a cooperative energy transfer from Ce3+ to Yb3+ ions. The high quantum efficiency of the films implies that Ce3+,Yb3+ co-doped Y3A15O12 films have potential application by tuning the solar spectrum to enhance the efficiency of silicon solar cells.展开更多
Using pentamethylidyne dye as a saturable absorber,we have obtained pulses close to Fourier-transform limit from colliding pulse mode-locked Nd:YAG and Nd:phosphate glass lasers with minim pulse durations of 8 psec an...Using pentamethylidyne dye as a saturable absorber,we have obtained pulses close to Fourier-transform limit from colliding pulse mode-locked Nd:YAG and Nd:phosphate glass lasers with minim pulse durations of 8 psec and 3.7 psec,respectively.展开更多
Transparent thin layer indium tin oxide was coated on polyethylene tetraphetalate (PET) substrate by means of spin coating process and its opto-electronic properties have been investigated. The surface treated by puls...Transparent thin layer indium tin oxide was coated on polyethylene tetraphetalate (PET) substrate by means of spin coating process and its opto-electronic properties have been investigated. The surface treated by pulse Nd-YAG laser. Pulse frequency, duration and energy were, 1000 Hz, 0.2 to 20 ms and 25 to 40 J respectively. The effect of treatment on crystallization, optical properties and bonding processes of the thin layer was investigated. The results show that ITO coated on flexible PET substrates is conductive and transparent. The sheet transparency for a 350 nm thickness in the visible range is more than 83.6%. Using Nd-YAG laser increased conductivity by a factor of 100 times and causes higher bonding performances.展开更多
Background and Objective: Unwanted hair growth is a discomforting issue affecting both genders. People have tried various methods to get rid of this situation. This study aims to evaluate the efficacy and safety of a ...Background and Objective: Unwanted hair growth is a discomforting issue affecting both genders. People have tried various methods to get rid of this situation. This study aims to evaluate the efficacy and safety of a combined Alexandrite and Nd:YAG laser treatment for permanent hair removal, drawing insights from existing literature. Materials and Methods:This study included a total of 2127 patients (302 males, 1825 females) aged 18 - 65, with complete data, who underwent hair removal treatment between December 2018 and April 2021. These patients were treated using the Duetta laser system (Quanta system, Samarate, Italy), combining Alexandrite 755 nm and Nd:YAG 1064 nm wavelengths. The patients’ skin types were classified according to the Fitzpatrick classification scale. Target area/areas for laser hair removal was/were determined. Laser parameters, pulse counts, pain levels assessed through the Visual Pain Scale (VPS), and patient satisfaction were documented based on skin types. Findings: Across various skin types, Types I - II exhibited the highest treatment success rates (87%), with the axillary region achieving the highest rate (83%) and the face region achieving the lowest rate (75%). Pain scale analysis indicated that 98% of patients tolerated the procedure well. Patient satisfaction levels exceeded 90%. Evaluation of complication rates revealed minimal occurrences. Conclusion: The combined Alexandrite and Nd:YAG laser system demonstrates both efficacy and safety across diverse skin types, attributed to its notable success rates, minimal adverse effects, and high patient tolerance.展开更多
文摘BACKGROUND This case of gestational gingival tumor is huge and extremely rare in clinical practice.As the growth location of this gingival tumor is in the upper anterior tooth area,it seriously affects the pregnant woman's speech and food,causing great pain to the patient.The use of Nd:YGA water mist laser to remove the gingival tumor resulted in minimal intraoperative bleeding,minimal adverse reactions,and good postoperative healing,which is worthy of clinical promotion and application.CASE SUMMARY The patient,a pregnant woman,reported a large lump in her mouth on the first day of postpartum treatment.Based on medical history and clinical examination,the diagnosis was diagnosed as gestational gingival tumor.Postoperative pathological biopsy also confirmed this diagnosis.The use of Nd:YAG water mist laser to remove the tumor resulted in minimal intraoperative bleeding,clear surgical field of view,short surgical time,and good postoperative healing.CONCLUSION In comparison to traditional surgery,Nd:YAG water mist laser surgery is minimally invasive,minimizes cell damage,reduces bleeding,ensures a clear field of vision,and virtually eliminates postoperative edema,carbonization,and the risk of cross infection.It has unique advantages in oral soft tissue surgery for pregnant patients.Therefore,the clinical application of Nd:YAG water mist laser for the treatment of gestational gingival tumors is an ideal choice.
基金National Natural Science Foundation of China(Nos.10675126,10375068))
文摘A multipulse Nd:YAG (Neodym-yttrium aluminium garnet) laser Thomson scattering diagnostic system developed was recently applied on HT-7 tokamak to obtain more accurate electron temperatures. A CAMAC-based real-time computer system for laser control, data acquisition, analysis and calibration was investigated in detail. Furthermore, the reliability and accuracy of this diagnostic system were demonstrated by comparing the results with those of a soft-X ray diagnostic system.
基金the National Natural Science Foundation of China (No.50474084).
文摘A pulsed Nd:YAG (yttrium aluminum garnet) laser-based technique was employed to clad low silicon steel with preplaced Si and Fe mixed powders for high Si content. The surface morphology, microstructural evolution, phase composition, and Si distribution, within the obtained cladding coatings, were characterized by optical microscopy (OM), field emission scanning electron microscopy (FE-SEM), with associated energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM), and X-ray diffraction (XRD). The microhardness was also measured along the depth direction of the specimens, A crack- and pore-free cladding coating through excellent metallurgical bonding with the substrate was successfully prepared on low silicon steel by means of optimized single-track and multi-track laser cladding. The phases of the coating are a-Fe, T-Fe, and FeSi. The high microhardness of the lasercladding zone is considered as an increase in Si content and as the refined microstructure produced by the laser treatment. The Si contents of the cladding coatings were about 5.8wt% in the single-track cladding and 6.5wt% in the multi-track cladding, respectively.
文摘We report the specification of a compact and stable side diode-pumped Q-switched pulsed Nd:YAG laser. We ex- perimentally study and compare the performance of the pulsed Nd:YAG laser in the free-running and Q-switched modes at different pulse repetition rates from 1 Hz to 100 Hz. The laser output energy is stabilized by using a special configu- ration of the optical resonator. In this laser, an unsymmetrical concave-concave resonator is used and this structure helps the mode volume to be nearly fixed when the pulse repetition rate is increased. According to the experimental results in the Q-switched operation, the laser output energy is nearly constant around 70 mJ with an FWHM pulse width of 7 ns at 100 Hz. The optical-to-optical conversion efficiency in the Q-switched regime is 17.5%.
基金supported by the Tarbiat Modares University and Iranian National Center for Laser Science and Technology
文摘Laser transformation hardening (LTH) was applied to the surface of the AISI 420 martensitic stainless steel by a pulsed Nd:YAG laser to obtain optimum hardness. The influences of process parameters (laser pulse energy, duration time, and travel speed) on the depth and hardness of laser treated area were investigated. Image analysis of SEM microstructure of AISI 420 showed that plate-like carbide have almost fully and (30-40)% of globular carbide particles dissolved into the matrix after laser transformation hardening by pulsed laser and the microstructure was refined to obtain controlled tempered martensite microstructure with 450 VHN hardness.
基金Project supported by the National Key Research and Development Program of China(Grant No.2016YFB0402103)the Knowledge Innovation Program of the Chinese Academy of Sciences(Grant No.GJJSTD20180004)the Fund of Technical Institute of Physics and Chemistry,Chinese Academy of Sciences(Grant No.Y8A9021H11)。
文摘The influence of pumping laser pulse on the property of quasi-continuous-wave(QCW)diode-side-pumped Nd:YAG laser is investigated theoretically and experimentally.Under remaining a fixed duty cycle,the average output power increases,and the corresponding thermal focal length shorten with the increase of the pump pulse duration,which attributes to the decrease of the ratio of pulse buildup time to the pulse duration.At a pump power of 146 W,the laser output power changes from 65.1 W to 81.2 W when the pulse duration is adjusted from 150μs to 1000μs,confirming a significant enhancement of 24.7%.A laser rate equation model incorporating the amplified spontaneous emission is also utilized and numerically solved,and the simulated results agree well with the experimental data.
文摘A hybrid-pumped Nd:YAG pulse laser with a double-pass two-rod configuration is presented. The focal length of offset lens is particularly studied to compensate for the thermal lens effect and depolarization. For input pulse energy of 141 μJ with pulse duration of 754ps, the pulse laser system delivers 526mJ pulse energy and 728ps pulse width output at lO Hz with pulse profile shape preservation. The energy stability of the laser pulse is less than 3%, and the beam quality factor M2 is less than 2.26.
基金Funded by the China Postdoctoral Science Foundation(No.2012M511801)the National Natural Science Foundation of China(Nos.11474104 and 51372092)
文摘Ce3+, Yb3+ co-doped Y3Al5O12 films were prepared by pulse laser deposition. X-ray diffraction, X-ray photoelectron spectroscopy, photoluminescence spectra were used to characterize their structural and luminescent properties. Near-infrared quantum cutting from the films was observed via a cooperative energy transfer from Ce3+ to Yb3+ ions. The high quantum efficiency of the films implies that Ce3+,Yb3+ co-doped Y3A15O12 films have potential application by tuning the solar spectrum to enhance the efficiency of silicon solar cells.
文摘Using pentamethylidyne dye as a saturable absorber,we have obtained pulses close to Fourier-transform limit from colliding pulse mode-locked Nd:YAG and Nd:phosphate glass lasers with minim pulse durations of 8 psec and 3.7 psec,respectively.
文摘Transparent thin layer indium tin oxide was coated on polyethylene tetraphetalate (PET) substrate by means of spin coating process and its opto-electronic properties have been investigated. The surface treated by pulse Nd-YAG laser. Pulse frequency, duration and energy were, 1000 Hz, 0.2 to 20 ms and 25 to 40 J respectively. The effect of treatment on crystallization, optical properties and bonding processes of the thin layer was investigated. The results show that ITO coated on flexible PET substrates is conductive and transparent. The sheet transparency for a 350 nm thickness in the visible range is more than 83.6%. Using Nd-YAG laser increased conductivity by a factor of 100 times and causes higher bonding performances.
文摘Background and Objective: Unwanted hair growth is a discomforting issue affecting both genders. People have tried various methods to get rid of this situation. This study aims to evaluate the efficacy and safety of a combined Alexandrite and Nd:YAG laser treatment for permanent hair removal, drawing insights from existing literature. Materials and Methods:This study included a total of 2127 patients (302 males, 1825 females) aged 18 - 65, with complete data, who underwent hair removal treatment between December 2018 and April 2021. These patients were treated using the Duetta laser system (Quanta system, Samarate, Italy), combining Alexandrite 755 nm and Nd:YAG 1064 nm wavelengths. The patients’ skin types were classified according to the Fitzpatrick classification scale. Target area/areas for laser hair removal was/were determined. Laser parameters, pulse counts, pain levels assessed through the Visual Pain Scale (VPS), and patient satisfaction were documented based on skin types. Findings: Across various skin types, Types I - II exhibited the highest treatment success rates (87%), with the axillary region achieving the highest rate (83%) and the face region achieving the lowest rate (75%). Pain scale analysis indicated that 98% of patients tolerated the procedure well. Patient satisfaction levels exceeded 90%. Evaluation of complication rates revealed minimal occurrences. Conclusion: The combined Alexandrite and Nd:YAG laser system demonstrates both efficacy and safety across diverse skin types, attributed to its notable success rates, minimal adverse effects, and high patient tolerance.