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Green Vertical‑Cavity Surface‑Emitting Lasers Based on InGaN Quantum Dots and Short Cavity 被引量:1
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作者 Tao Yang Yan‑Hui Chen +7 位作者 Ya‑Chao Wang Wei Ou Lei‑Ying Ying Yang Mei Ai‑Qin Tian Jian‑Ping Liu Hao‑Chung Guo Bao‑Ping Zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第12期115-125,共11页
Room temperature low threshold lasing of green GaNbased vertical cavity surface emitting laser(VCSEL)was demonstrated under continuous wave(CW)operation.By using self-formed InGaN quantum dots(QDs)as the active region... Room temperature low threshold lasing of green GaNbased vertical cavity surface emitting laser(VCSEL)was demonstrated under continuous wave(CW)operation.By using self-formed InGaN quantum dots(QDs)as the active region,the VCSEL emitting at 524.0 nm has a threshold current density of 51.97 A cm^(-2),the lowest ever reported.The QD epitaxial wafer featured with a high IQE of 69.94%and theδ-function-like density of states plays an important role in achieving low threshold current.Besides,a short cavity of the device(~4.0λ)is vital to enhance the spontaneous emission coupling factor to 0.094,increase the gain coefficient factor,and decrease the optical loss.To improve heat dissipation,AlN layer was used as the current confinement layer and electroplated copper plate was used to replace metal bonding.The results provide important guidance to achieving high performance GaN-based VCSELs. 展开更多
关键词 green vertical cavity surface emitting laser GaN Low threshold InGaN quantum dots
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An all-solid-state high power quasi-continuous-wave tunable dual-wavelength Ti:sapphire laser system using birefringence filter 被引量:1
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作者 丁欣 马洪梅 +4 位作者 邹雷 邹跃 温午麒 王鹏 姚建铨 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第7期1991-1995,共5页
This paper describes a tunable dual-wavelength Ti:sapphire laser system with quasi-continuous-wave and high-power outputs. In the design of the laser, it adopts a frequency-doubled Nd:YAG laser as the pumping source... This paper describes a tunable dual-wavelength Ti:sapphire laser system with quasi-continuous-wave and high-power outputs. In the design of the laser, it adopts a frequency-doubled Nd:YAG laser as the pumping source, and the birefringence filter as the tuning element. Tunable dual-wavelength outputs with one wavelength range from 700 nm to 756.5 nm, another from 830 nm to 900mn have been demonstrated. With a pump power of 23 W at 532 nm, a repetition rate of 7 kHz and a pulse width of 47.6 ns, an output power of 5.1 W at 744.8 nm and 860.9 nm with a pulse width of 13.2 ns and a line width of 3 nm has been obtained, it indicates an optical-to-optical conversion efficiency of 22.2%. 展开更多
关键词 all-solid-state DUAL-WAVELENGTH Ti:sapphire laser birefringence filter
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Selective Laser Melting of Novel SiC and TiC Strengthen 7075 Aluminum Powders for Anti-Cracks Application
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作者 Yingjie Li Hanlin Liao 《Journal of Materials Science and Chemical Engineering》 2024年第4期136-142,共7页
The aerospace and military sectors have widely used AA7075, a type of 7075 aluminum alloy, due to its exceptional mechanical performance. Selective laser melting (SLM) is a highly effective method for producing intric... The aerospace and military sectors have widely used AA7075, a type of 7075 aluminum alloy, due to its exceptional mechanical performance. Selective laser melting (SLM) is a highly effective method for producing intricate metallic components, particularly in the case of aluminum alloys like Al-Si-Mg. Nevertheless, the production of high-strength AA7075 by SLM is challenging because of its susceptibility to heat cracking and elemental vaporization. In this study, AA7075 powders were mechanically mixed with SiC and TiC particles. Subsequently, this new type of AA7075 powder was effectively utilized in green laser printing to create solid components with fine-grain strengthening microstructures consisting of equiaxial grains. These as-printed parts exhibit a tensile strength of up to 350 MPa and a ductility exceeding 2.1%. Hardness also increases with the increasing content of mixed powder, highlighting the essential role of SiC and TiC in SLM for improved hardness and tensile strength performance. . 展开更多
关键词 Selective laser Melting (SLM) AA 7075 Fine Grain Strengthen TiC SIC green laser
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Effect of inhomogeneous broadening on threshold current of GaN-based green laser diodes 被引量:3
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作者 Yipeng Liang Jianping Liu +7 位作者 Masao Ikeda Aiqin Tian Renlin Zhou Shuming Zhang Tong Liu Deyao Li Liqun Zhang Hui Yang 《Journal of Semiconductors》 EI CAS CSCD 2019年第5期67-70,共4页
The inhomogeneous broadening parameter and the internal loss of green LDs are determined by experiments and theoretical fitting. It is found that the inhomogeneous broadening plays an important role on the threshold c... The inhomogeneous broadening parameter and the internal loss of green LDs are determined by experiments and theoretical fitting. It is found that the inhomogeneous broadening plays an important role on the threshold current density of green LDs. The green LD with large inhomogeneous broadening even cannot lase. Therefore, reducing inhomogeneous broadening is a key issue to improve the performance of green LDs. 展开更多
关键词 GaN green laser DIODE INHOMOGENEOUS BROADENING threshold current density
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A high-power high-stability Q-switched green laser with intracavity frequency doubling using a diode-pumped composite ceramic Nd:YAG laser 被引量:7
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作者 王与烨 徐德刚 +2 位作者 刘长明 王卫鹏 姚建铨 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第9期315-320,共6页
We successfully obtain a high-average-power high-stability Q-switched green laser based on diode-side-pumped composite ceramic Nd:YAG in a straight piano-concave cavity. The temperature distribution in composite cera... We successfully obtain a high-average-power high-stability Q-switched green laser based on diode-side-pumped composite ceramic Nd:YAG in a straight piano-concave cavity. The temperature distribution in composite ceramic Nd:YAG crystal is numerically analyzed and compared with that of conventional Nd:YAG crystal. By using a composite ceramic Nd:YAG rod and a type-II high gray track resistance KTP (HGTR-KTP) crystal, a green laser with an average output power of 165 W is obtained at a repetition rate of 25 kHz, with a diode-to-green optical conversion of 14.68%, and a pulse width of 162 ns. To the best of our knowledge, both the output power and optical-to-optical efficiency are the highest values for green laser systems with intracavity frequency doubling of this novel composite ceramic Nd:YAG laser to date. The power fluctuation at around 160 W is lower than 0.3% in 2.5 hours. 展开更多
关键词 high-average-power green laser high stability composite ceramic Nd:YAG rod
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Diode end-pumped self-Q-switched and mode-locked Nd,Cr:YAG /KTP green laser 被引量:2
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作者 杜仕峰 王素梅 +5 位作者 张东香 冯宝华 张春雨 张玲 张治国 张世文 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第7期1522-1525,共4页
We first experimentally demonstrate a laser-diode end-pumped self-Q-switched and mode-locked Nd,Cr:YAG green laser with a KTP crystal as the intra-cavity frequency doubler. The device produces an average output power... We first experimentally demonstrate a laser-diode end-pumped self-Q-switched and mode-locked Nd,Cr:YAG green laser with a KTP crystal as the intra-cavity frequency doubler. The device produces an average output power of 680 mW at 532 nm. The corresponding pulse width of the Q-switched envelope of the green laser is 170 + 20 ns. The mode-locked pulses have a repetition rate of approximately 183 MHz and the average pulse duration is estimated to be around sub-nanosecond. It is found that the intra-cavity frequency doubling greatly improves the modulation depth and stability of the mode-locked pulses within the Q-switched envelope. 展开更多
关键词 frequency doubling Nd Cr:YAG crystal self-Q-switched and mode-locked pulses green laser
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Infrared Laser Pumped Green and Blue Laser Emissions from a Single Solid State Material Doped by Rare Earth Ions
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作者 黄艺东 黄妙良 +1 位作者 陈雨金 罗遵度 《Journal of Rare Earths》 SCIE EI CAS CSCD 2003年第3期307-314,共8页
The possible ways and progress of infrared or red laser pumped green and blue laser emissions from a single solid state material doped by rare earth ions are outlined. The green and blue lasers realized from infrared ... The possible ways and progress of infrared or red laser pumped green and blue laser emissions from a single solid state material doped by rare earth ions are outlined. The green and blue lasers realized from infrared laser pumped rare earth doped nonlinear laser crystals by means of self frequency conversion and from infrared laser pumped rare earth doped bulk, fiber and microsphere materials by means of frequency upconversion are introduced in detail. Other kinds of devices and methods are also compared. The typical nonlinear laser crystals such as YAl 3(BO 3) 4, GdAl 3(BO 3) 4, YCa 4O(BO 3) 3 , GdCa 4O(BO 3) 3, and the typical upconversion fluoride fibers are compared and analyzed. The major problems remaining to be solved and the developing trends in the area are also discussed. 展开更多
关键词 OPTICS solid state laser material blue and green lasers rare earth
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LD Pumped High Efficient Intracavity Frequency-Doubled Green Laser
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作者 陈进 于意仲 +2 位作者 朱孟 王鹏 王杰 《Transactions of Tianjin University》 EI CAS 2003年第1期1-6,共6页
A laser diode (LD) pumped Q switched high efficient intracavity frequency doubled Nd ∶YAG laser is reported here. The authors have designed an optical coupler and pointed out that the key to increasing harmonic conve... A laser diode (LD) pumped Q switched high efficient intracavity frequency doubled Nd ∶YAG laser is reported here. The authors have designed an optical coupler and pointed out that the key to increasing harmonic conversion efficiency is to decrease the loss of fundamental wave. In the experiments, a fundamental mode output laser was acquired. When the pumping power was 12 W, 2.6 W average output power at 1 064 nm with AO Q switch was obtained. 2.1 W average output power at 532 nm was obtained with intracavity frequency doubling, and the highest second harmonic conversion efficiency was 82 0 0. 展开更多
关键词 LD pumped solid state laser high efficient intracavity frequency doubled green laser
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Novel closed-cycle reaction mode for totally green production of Cu_(1.8)Se nanoparticles based on laser-generated Se colloidal solution
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作者 Zhangyu Gu Yisong Fan +7 位作者 Yixing Ye Yunyu Cai Jun Liu Shouliang Wu Pengfei Li Junhua Hu Changhao Liang Yao Ma 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第7期41-48,共8页
Non-stoichiometric copper selenide(Cu_(2-x)Se,x=0.18~0.25)nanomaterials have attracted extensive attentions due to their excellent thermoelectric,optoelectronic and photocatalytic performances.However,efficient produc... Non-stoichiometric copper selenide(Cu_(2-x)Se,x=0.18~0.25)nanomaterials have attracted extensive attentions due to their excellent thermoelectric,optoelectronic and photocatalytic performances.However,efficient production of Cu_(2-x)Se nanoparticles(NPs)through a green and convenient way is still hindered by the inevitable non-environmentally friendly operations in common chemical synthesis.Herein,we initially reveal the coexistence of seleninic acid content and elemental selenium(Se)NPs in pulsed laser-generated Se colloidal solution.Consequently,we put forward firstly a closedcycle reaction mode for totally green production of Cu_(1.8)Se NPs to exclude traditional requirements of high temperature and toxic precursors by using Se colloidal solution.In such closed-cycle reaction,seleninic acid works as the initiator to oxidize copper sheet to release cuprous ions which can catalyze the disproportion of Se NPs to form Se O_(3)^(2-)and Se^(2-)ions and further produce Cu_(2-x)Se NPs,and the by-product SeO_(3)^(2-)ions promote subsequent formation of cuprous from the excessive Cu sheet.In experiments,the adequate copper(Cu)sheet was simply dipped into such Se colloidal solution at 70℃,and then the stream of Cu_(1.8)SeNPs could be produced until the exhaustion of selenium source.The conversion rate of Se element reaches to more than 75%when the size of Se NPs in weakly acidic colloidal solution is limited between 1 nm and 50 nm.The laser irradiation duration shows negative correlation with the size of Se NPs and unobvious impact to the p H of the solution which both are essential to the high yield of Cu_(1.8)SeNPs.Before Cu sheet is exhausted,Se colloidal solution can be successively added without influences to the product quality and the Se conversion rate.Such green methodology positively showcases a brand-new and potential strategy for mass production of Cu_(2-x)Se nanomaterials. 展开更多
关键词 non-stoichiometric copper selenide green production selenium colloidal solution laser irradiation in liquids
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A 54-fs diode-pumped Kerr-lens mode-locked Yb:LuYSiO_(5) laser
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作者 于洋 陈月航 +8 位作者 田文龙 郑立 王阁阳 白川 田轩 麦海静 苏玉龙 朱江峰 魏志义 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期255-258,共4页
We demonstrate a Kerr-lens mode-locked Yb:Lu YSiO_(5)(Yb:LYSO)laser with the pulse duration of 54 fs,corresponding to a spectral bandwidth of 25 nm centered at 1062 nm.To the best of our knowledge,this is the shortest... We demonstrate a Kerr-lens mode-locked Yb:Lu YSiO_(5)(Yb:LYSO)laser with the pulse duration of 54 fs,corresponding to a spectral bandwidth of 25 nm centered at 1062 nm.To the best of our knowledge,this is the shortest pulse duration obtained from Yb:LYSO laser.At the repetition rate of 378.3 MHz,an output power of 111.6 m W is obtained using an output coupler with 0.6%transmittance,which can maintain long-time stable mode-locking more than 13 h. 展开更多
关键词 DIODE-PUMPED MODE-LOCKING FEMTOSECOND all-solid-state laser
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Cutting Experiment of Fraxinus mandshurica UsingWaterjet-Assisted CO_(2)Laser
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作者 Yueqiang Yu Minzheng Jiang +6 位作者 Sheng Gao Ting Jiang Bakary S.Doumbia Bo Yan Tingang Ma Kexin Ren Yinsong Liu 《Journal of Renewable Materials》 EI 2023年第9期3583-3593,共11页
High-quality wood products and valuable wood crafts receive everyone’s favor with the rapid development of the economy.In order to improve the cutting surface quality of wood forming parts,the cutting experiment of r... High-quality wood products and valuable wood crafts receive everyone’s favor with the rapid development of the economy.In order to improve the cutting surface quality of wood forming parts,the cutting experiment of renewable Fraxinus mandshurica was conducted by waterjet-assisted CO_(2)laser(WACL)technology.A quadratic mathematical model for describing the relationship between surface roughness changes and cutting parameters was established.The effects of cutting speed,flow pressure and laser power on the kerf surface roughness of Fraxinus mandshurica when cutting transversally were discussed by response surface method.The experimental results showed that kerf surface roughness decreased under a lower laser power,higher cutting speed and higher flow pressure.When the cutting speed was 30 mm/s,flow pressure was 1.58 MPa and laser power was 45 W,the actual surface roughness of the optimized Fraxinus mandshurica was 2.41μm,and it was in accord with the theoretically predicted surface roughness value of 2.54μm,so the model fitted the actual situation well.Through the analysis of 3D profile morphology and micromorphology,it was concluded that the optimized kerf surface of Fraxinus mandshurica was smoother,the cell wall was not destroyed and the tracheid was clear.It provides the theoretical basis for wood micromachining. 展开更多
关键词 green processing waterjet-assisted CO_(2)laser machining transverse cutting response surface method surface roughness
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直出式绿激光膀胱肿瘤剜除术与经尿道膀胱肿瘤等离子电切在治疗非肌层浸润性膀胱癌的围手术期疗效的比较
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作者 汪群锋 梁朝朝 +1 位作者 朱劲松 陈志洁 《现代泌尿生殖肿瘤杂志》 2024年第2期85-88,共4页
目的比较直出式绿激光膀胱肿瘤剜除术与经尿道膀胱肿瘤等离子电切术治疗非肌层浸润性膀胱癌(NMIBC)的疗效。方法回顾性分析2019年3月至2020年3月于安庆市立医院泌尿外科治疗的80例NMIBC患者的临床资料,通过随机数表法将80例患者均分为两... 目的比较直出式绿激光膀胱肿瘤剜除术与经尿道膀胱肿瘤等离子电切术治疗非肌层浸润性膀胱癌(NMIBC)的疗效。方法回顾性分析2019年3月至2020年3月于安庆市立医院泌尿外科治疗的80例NMIBC患者的临床资料,通过随机数表法将80例患者均分为两组,其中实验组采用直出式绿激光膀胱肿瘤剜除术,对照组采用经尿道膀胱肿瘤等离子电切术。对两组的术中出血量、术后膀胱冲洗时间、留置尿管时间、术后住院时间以及术中、术后并发症发生情况进行比较分析。结果两组患者手术均顺利完成,实验组在手术时间、复发率方面与对照组相比差异无统计学意义(P>0.05)。实验组术中出血量、术后膀胱冲洗时间、留置尿管时间、术后住院时间小于对照组;实验组在术后出血、闭孔神经反射和膀胱穿孔发生率明显低于对照组,差异有统计学意义(P<0.05)。结论直出式绿激光膀胱肿瘤剜除术治疗NMIBC较经尿道膀胱肿瘤等离子电切术更安全、有效,具有微创、出血少、并发症风险低等优点,值得临床推广使用。 展开更多
关键词 直出式绿激光 等离子电切术 非肌层浸润性膀胱癌 手术治疗
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基于三维激光点云数据的校园绿地乔木三维绿量对比研究——以广西生态工程职业技术学院为例
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作者 肖万娟 唐健灵 +1 位作者 骆姚瑶 苏玉峰 《绿色科技》 2024年第11期15-21,共7页
树冠是指树干以上连同其生枝叶的部分,其体积的大小是估算树木三维绿量的重要参数。校园绿地中乔木树冠形态各异,结构复杂,树木树冠体积的准确、自动、无损测量是校园绿地调查中的一个重要研究项目。随机抽取广西生态工程职业技术学院内... 树冠是指树干以上连同其生枝叶的部分,其体积的大小是估算树木三维绿量的重要参数。校园绿地中乔木树冠形态各异,结构复杂,树木树冠体积的准确、自动、无损测量是校园绿地调查中的一个重要研究项目。随机抽取广西生态工程职业技术学院内5个树种共计25棵乔木的三维激光点云数据与树木三维绿量冠幅-冠高公式法进行了对比研究。以三维激光扫描仪获取的三维激光点云数据基于不规则三角网法计算乔木树冠体积。计算结果对比表明:测量值与参考值的均方根误差RMSE为2.913、绝对误差最大值为7.22 m3,最小值为0.17 m3;相对误差最大值为11.06%,最小值为0.12%;平均绝对误差为2.20 m3,平均相对误差为3.13%,该算法不用考虑树冠的形状,减少了人为判别导致的差异。因此,以三维激光扫描仪获取点云数据,运用不规则三角网法自动提取校园绿地乔木树冠体积快捷、有效、可推广。 展开更多
关键词 乔木三维绿量 树冠体积 三维激光点云 大学校园绿地
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509 nm高功率宽调谐外腔面发射激光器
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作者 王涛 彭雪芳 +6 位作者 贺亮 沈小雨 朱仁江 蒋丽丹 佟存柱 宋晏蓉 张鹏 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第12期198-204,共7页
报道了一种高功率宽调谐外腔面发射绿光激光器,利用设计的1018 nm半导体增益芯片、折叠镜以及后端镜构成结构紧凑的V型腔,使用长度为10 mm的Ⅰ类相位匹配三硼酸锂(LiB_(3)O_(5),LBO)非线性频率变换晶体进行腔内倍频,实现了509 nm波长的... 报道了一种高功率宽调谐外腔面发射绿光激光器,利用设计的1018 nm半导体增益芯片、折叠镜以及后端镜构成结构紧凑的V型腔,使用长度为10 mm的Ⅰ类相位匹配三硼酸锂(LiB_(3)O_(5),LBO)非线性频率变换晶体进行腔内倍频,实现了509 nm波长的高功率绿光输出.通过在腔内插入双折射滤波片(birefringent filter,BRF),可获得连续调谐的激光波长.当BRF厚度为1 mm时,基频激光和倍频绿光的波长调谐范围分别为47.1 nm和20.1 nm.可调谐绿光的最大输出功率为8.23 W,对应的倍频转换效率为68.2%,相应的从吸收泵浦光到倍频绿光的光-光转换效率为16.6%. 展开更多
关键词 外腔面发射激光器 腔内倍频 双折射滤波片 可调谐
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不同经尿道前列腺切除术治疗良性前列腺增生的疗效与安全性分析
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作者 吴奔 周睿 +3 位作者 鲍彤 汪群峰 疏翀 吴骁翔 《实用医学杂志》 CAS 北大核心 2024年第22期3202-3207,共6页
目的探究不同经尿道前列腺切除术治疗良性前列腺增生的疗效与安全性分析。方法选取2021年1月至2023年5月本院收治的良性前列腺增生患者215例临床资料开展回顾性分析,根据手术方式分为经尿道前列腺等离子电切术治疗的等离子电切术组(n=81... 目的探究不同经尿道前列腺切除术治疗良性前列腺增生的疗效与安全性分析。方法选取2021年1月至2023年5月本院收治的良性前列腺增生患者215例临床资料开展回顾性分析,根据手术方式分为经尿道前列腺等离子电切术治疗的等离子电切术组(n=81)、经尿道前列腺激光切除术治疗的激光切除术组(n=92)、经尿道前列腺绿激光剜除术治疗的绿激光剜除术组(n=42),比较三组围手术期指标(手术时间、术中出血量、膀胱冲洗时间、留置尿管时间、术后血红蛋白浓度、住院时间)、尿动力学指标(RUV、IPSS评分、Qmax、QOL评分)、术后并发症发生情况的差异。结果绿激光剜除术组、激光切除术组总有效率高于等离子电切术组(P<0.05)。3组住院时间比较差异无统计学意义(P>0.05),但绿激光剜除术组手术时间>激光切除术组>等离子电切术组(P<0.05),绿激光剜除术组、激光切除术组术中出血量、膀胱冲洗时间、留置尿管时间<等离子电切术组,且术后血红蛋白浓度>等离子电切术组(P<0.05)。重复测量方差分析结果显示,3组术后1个月、术后3个月RUV、IPSS评分、QOL评分与术前相比均降低,而Qmax与术前相比均升高(P<0.05),且激光切除术组与绿激光剜除术组术后1个月、术后3个月RUV、IPSS评分、QOL评分均低于等离子电切术组,Qmax均高于等离子电切术组(P<0.05),但激光切除术组与绿激光剜除术组术后1个月、术后3个月RUV、IPSS评分、Qmax、QOL评分比较差异无统计学意义(P>0.05)。绿激光剜除术组术后并发症总发生率<激光切除术组<等离子电切术组(7.14%vs.21.74%vs.35.80%,P<0.05)。结论3种手术方式治疗良性前列腺增生均具有较好疗效,但经尿道前列腺激光切除术与绿激光剜除术疗效与安全性均优于经尿道前列腺等离子电切术,可促进患者早期康复,且经尿道前列腺绿激光剜除术治疗安全性最好。 展开更多
关键词 良性前列腺增生 经尿道 等离子电切术 激光切除术 绿激光剜除术
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Cu箔集流体飞秒激光深刻蚀织构化及其对锂离子电池性能的影响
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作者 王京博 曹利 +2 位作者 李松原 肖荣诗 黄婷 《表面技术》 EI CAS CSCD 北大核心 2024年第1期115-122,共8页
目的 使用飞秒激光在Cu箔表面深刻蚀织构化,制备微纳沟槽结构,提高锂离子电池Si电极循环稳定性。方法 系统研究激光能量密度、单位点有效脉冲数对厚度为9μm的Cu箔的表面形貌和微纳结构的影响规律,根据结果设计不同沟槽密度和沟槽深度... 目的 使用飞秒激光在Cu箔表面深刻蚀织构化,制备微纳沟槽结构,提高锂离子电池Si电极循环稳定性。方法 系统研究激光能量密度、单位点有效脉冲数对厚度为9μm的Cu箔的表面形貌和微纳结构的影响规律,根据结果设计不同沟槽密度和沟槽深度的Cu箔,并组装成Si电极锂离子半电池,通过循环测试及循环后电极形貌揭示其稳定性提升的内在机理。结果 最佳的激光能量密度为3.18 J/cm^(2),此时改变单位点有效脉冲数和扫描间距可有效控制刻蚀沟槽的密度和深度。Si电极的循环稳定性随着Cu箔表面沟槽密度和沟槽深度的增加而逐渐提升,当沟槽密度为75%、沟槽深度为6μm时,循环300圈后剩余的容量高达911 mA·h/g,保持率为89%,电极形貌相对最完整、稳定。结论 刻蚀表面纳米结构增加了电极层与集流体之间的黏结强度;微米沟槽结构进一步保护了电极层,缓解了体积膨胀效应。采用Cu箔集流体深刻蚀显著改善了Si电极的剥离和开裂现象,实现了其电化学性能的提升。 展开更多
关键词 绿光飞秒激光 激光刻蚀 Cu箔集流体 Si电极 循环稳定性
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基于Ti3C2Tx-PVA被动调Q的低噪声556 nm腔内倍频黄绿光激光器
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作者 徐知微 闫佳乐 +3 位作者 王国珍 李奔 陆宝乐 白杨 《光子学报》 EI CAS CSCD 北大核心 2024年第3期38-48,共11页
采用液相剥离法获得厚度约为3.2 nm、层数约为3至4层的碳化钛纳米片(Ti_(3)C_(2)T_(x)),结合旋涂法制备出Ti_(3)C_(2)T_(x)-聚乙烯醇(Ti_(3)C_(2)T_(x)-PVA)薄膜,并借助拉曼光谱、原子力显微镜和平衡双探测系统对Ti_(3)C_(2)T_(x)纳米... 采用液相剥离法获得厚度约为3.2 nm、层数约为3至4层的碳化钛纳米片(Ti_(3)C_(2)T_(x)),结合旋涂法制备出Ti_(3)C_(2)T_(x)-聚乙烯醇(Ti_(3)C_(2)T_(x)-PVA)薄膜,并借助拉曼光谱、原子力显微镜和平衡双探测系统对Ti_(3)C_(2)T_(x)纳米片的物相组成、厚度及可饱和吸收性能进行了表征。将Ti_(3)C_(2)T_(x)-PVA薄膜作为可饱和吸收体应用于一种808 nm半导体激光二极管端面泵浦Nd∶YAG陶瓷/LBO腔内倍频的556 nm黄绿激光器中实现被动调Q。在分析布儒斯特偏振器和双折射晶体协同选频滤波机理的基础上,通过两者的协同使用,抑制了1116 nm和1123 nm处光谱腔内振荡并进一步压缩了1112 nm处p-偏振光的纵模个数。在5.1 W最高激光二极管泵浦功率下,获得了平均输出功率为86.2 mW、重复频率为745.8 kHz、脉冲宽度为46 ns的556 nm被动调Q脉冲黄绿激光输出。4 h内测得功率不稳定度和激光噪声仅为±0.39%和0.37%,光束质量评价因子为M2x=1.837和M^(2)^(y)=1.975。Ti_(3)C_(2)T_(x)-PVA薄膜被动调Q结合“布儒斯特偏振器+双折射晶体”协同选频滤波技术方案为开发高稳定性、低噪声脉冲黄绿激光提供有价值的参考。 展开更多
关键词 被动调Q Ti3C2Tx-PVA 低噪声 556 nm黄绿激光 选频滤波
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可调谐DFB激光器泵浦的PPLN绿色倍频光源
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作者 白思思 阙天行 +2 位作者 李京儒 连霜 姜培培 《激光杂志》 CAS 北大核心 2024年第7期42-48,共7页
为研制脉冲宽度、重复频率以及输出功率可调谐至单光子级别的可见光波段高重频纳秒级窄脉冲光源,提出了一种基于增益调制型DFB激光器和PPLN晶体的绿色倍频光源设计方案。通过自制的纳秒级高速驱动电路以脉冲方式驱动DFB激光器产生固定... 为研制脉冲宽度、重复频率以及输出功率可调谐至单光子级别的可见光波段高重频纳秒级窄脉冲光源,提出了一种基于增益调制型DFB激光器和PPLN晶体的绿色倍频光源设计方案。通过自制的纳秒级高速驱动电路以脉冲方式驱动DFB激光器产生固定波长的泵浦源;利用光纤半导体衰减器调节衰减量,调制泵浦光强度;采用PPLN晶体作为非线性晶体材料,通过其可调谐特性得到准相位匹配的绿色倍频激光输出。实验结果表明,DFB激光器输出的泵浦光功率和中心波长稳定,脉冲宽度1.02 ns~10.25 ns、工作频率1 Hz~10 MHz连续独立可调,泵浦光功率衰减至-44.61 dB时工作于532.96 nm波段的绿色倍频光输出脉冲平均光子数约为384 N,倍频光-光转换效率9.3%。 展开更多
关键词 纳秒级窄脉冲 增益调制 DFB激光器 绿色倍频激光 光纤半导体衰减器
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激光加工氧化铝生瓷微结构制备方法
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作者 马栋栋 淦作腾 +3 位作者 张鑫磊 王杰 程换丽 刘曼曼 《微纳电子技术》 CAS 2024年第8期45-51,共7页
Al_(2)O_(3)陶瓷具备机械强度高、耐热性好、耐腐蚀的优势。基于激光减材加工技术,介绍了Al_(2)O_(3)生瓷激光减材加工的基本原理。通过建立激光能量密度模型,计算改变激光加工参数时的激光能量密度,从而对加工深度进行预测。通过对比... Al_(2)O_(3)陶瓷具备机械强度高、耐热性好、耐腐蚀的优势。基于激光减材加工技术,介绍了Al_(2)O_(3)生瓷激光减材加工的基本原理。通过建立激光能量密度模型,计算改变激光加工参数时的激光能量密度,从而对加工深度进行预测。通过对比激光加工功率、填充间距、扫描速度和激光重复频率的实验结果,分析了不同加工参数对Al_(2)O_(3)生瓷加工深度和表面粗糙度的影响规律。实验结果表明,通过使用合适的加工参数,在Al_(2)O_(3)生瓷上可制备深度12~280μm和表面粗糙度0.5~1.0μm的腔体。单脉冲能量是影响Al_(2)O_(3)生瓷加工深度的主要因素。在激光能量密度不变的情况下,单脉冲能量(20~200μJ)越高,加工深度越深。该研究验证了激光减材加工技术在Al_(2)O_(3)生瓷腔体直接成型加工中的可行性,推动了激光加工腔体技术在陶瓷封装外壳中的应用。 展开更多
关键词 激光减材加工 Al_(2)O_(3)生瓷 加工深度 表面粗糙度 单脉冲能量
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清热渗湿汤辅助治疗良性前列腺增生PVP术后临床研究
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作者 沈剑超 戎路华 +3 位作者 董丽萍 徐晔 张建华 方志海 《新中医》 CAS 2024年第5期95-99,共5页
目的:观察清热渗湿汤辅助治疗良性前列腺增生(BPH)经尿道选择性绿激光前列腺汽化术(PVP)术后的临床疗效。方法:采用随机数字表法将150例择期行PVP的BPH患者分为观察组与对照组各75例。2组均给予PVP治疗,对照组术后加用盐酸坦洛新缓释片... 目的:观察清热渗湿汤辅助治疗良性前列腺增生(BPH)经尿道选择性绿激光前列腺汽化术(PVP)术后的临床疗效。方法:采用随机数字表法将150例择期行PVP的BPH患者分为观察组与对照组各75例。2组均给予PVP治疗,对照组术后加用盐酸坦洛新缓释片治疗,观察组在对照组基础上联合清热渗湿汤治疗。比较2组治疗前后中医证候积分、国际前列腺症状评分(IPSS评分)、排尿功能、生活质量(QOL)评分、性激素水平;比较2组临床疗效及不良反应发生率。结果:观察组总有效率92.00%,高于对照组78.67%(P<0.05)。2组治疗后中医证候积分、IPSS评分、QOL评分均较治疗前降低(P<0.05),且观察组治疗后上述指标低于对照组(P<0.05)。2组治疗后日间排尿次数、夜间排尿次数、尿急次数、残余尿量(PVR)、促黄体生成素(LH)、雌二醇(E_(2))水平均较治疗前降低(P<0.05),最大尿流率(Qmax)、睾酮(T)、催乳素(PRL)水平均升高(P<0.05);观察组治疗后日间排尿次数、夜间排尿次数、尿急次数、PVR、LH、E_(2)水平低于对照组(P<0.05);Qmax、T、PRL水平高于对照组(P<0.05)。2组不良反应发生率比较,差异无统计学意义(P>0.05)。结论:清热渗湿汤辅助治疗PVP术后BPH疗效确切,能改善患者排尿功能与性激素水平,提高生活质量,安全性较高。 展开更多
关键词 良性前列腺增生 经尿道选择性绿激光前列腺汽化术 清热渗湿汤 盐酸坦洛新缓释片 排尿功能 性激素
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