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本文简要的介绍了用He-Ne激光器做光源的激光衍射式粒度分布测定器检测钻井用泥浆中微小粒子分布的情况。 相似文献
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临床观察表明低能量He-Ne激光血管内照射结合氧疗治疗脑梗塞,疗效较单用低能量He-Ne激光血管内照射血液效果更佳,是一种治疗脑梗塞简便有效的方法,病人乐于接受,值得深入研究。 相似文献
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本文提出采用 He—Ne 激光和远红外 HCN 激光在空气中声光衍射的方法,标定 HCN 激光器作等离子体密度涨落散射研究时探测器的灵敏度。实验中用激光外差探测测定出 He—Ne 激光一级和零级衍射光强的比值,这对于用 HCN 激光器作等离子体密度涨落研究有重要意义。 相似文献
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激光对蚕豆幼苗紫外线-B辐射损伤的防护作用 总被引:14,自引:3,他引:11
用不同剂量的He Ne激光和CO2 激光辐射蚕豆 (ViciafabaL .)种子胚 ,对其幼苗进行丙二醛 (MDA)和抗坏血酸 (AsA)含量测定。结果发现He Ne激光的效果优于CO2 激光 ;He Ne激光的最佳辐射剂量为 5 4 3mW·mm-2 ,最佳辐射时间为 5min。先用He Ne激光辐射蚕豆种子 ,待其长至幼苗时 ,在光背景 (PAR) 70 μmol·m-2 ·s-1条件下 ,用 3 0 3kJ·m-2 UV B照射 7h/d ,然后对其超氧化物歧化酶 (SOD) ,过氧化物酶 (POD) ,过氧化氢酶(CAT)酶活性以及同工酶谱进行测定。结果发现 ,He Ne激光辐射可提高SOD ,POD ,CAT酶活性 ;改变SOD ,CAT同工酶谱。从而说明 ,激光对UV B辐射损伤植物具有一定的防护作用。 相似文献
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我院近期用CO_2激光打洞,He—Ne激光 局部照射治愈8侧耳廓假性囊肿。 我们用30W的CO_2激光机在囊肿上、下方各打一个洞,每天用8mW的He—Ne激光仪照射局部15分钟,3~8天即全部治愈。 相似文献
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氦氖激光对促进人工种植牙骨整合的临床研究 总被引:1,自引:0,他引:1
随机对126例牙列缺损患者施人工种植牙术前、术后氦氖激光照射,防治种植术后感染,促进骨整合,设照射组和对照组各115枚牙、结果提高了手术成功率,有效地防治了术后感染,通过临床观察和结果统计分析,有极显著意义,氦氖激光能使种植区域的免疫,循环,创口愈合及骨痂代谢均处于最佳状态,提高种植成功率. 相似文献
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An InGaAsP 1.5 ?m laser, with one facet antireflection coated, has been incorporated into a diffraction grating external cavity. The lasing wavelength could be tuned over a 55 nm range about the centre wavelength of 1.5 ?m by rotating the grating. Furthermore, it was found that the emission spectrum was extremely narrow; beat-frequency measurements at 1523 nm against an HeNe laser showed it to be of the order of 10 kHz. 相似文献
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激光的生物学效应,一方面依赖于激光特性,另一方面依赖于生物体内部对激光的敏感性。本文介绍应用He-Ne激光处理油松种子获得了有益的试验结果,并从植物细胞的双分子层结构模型出发,讨论了对生物细胞膜物理特性及膜渗透性的影响,并探讨了激光处理油松种子提高萌发率的作用机理。 相似文献
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A photodisplacement microscope has been realised, using a modulated semiconductor laser as the heating source and a phase sensitive HeNe laser probe for detection. Experimental results indicate that the instrument can have a wide range of applicability, including problems in nondestructive examination. 相似文献
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本文报导了相位共轭反馈He-Ne激光器的噪声特性,观测到激光起伏存在两种变化过程,即几十赫兹的快变过程和秒量级的慢变过程,在远离半腔长整数倍处,相位共轭反馈只影响其激光器本征噪声的周期性,其噪声幅度变化较小,在一倍腔长处,噪声起伏约为激光输出的35%. 相似文献
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Ahrenkiel R. Thomas S. Prinz G. Krebs J. Maisch W. 《Quantum Electronics, IEEE Journal of》1980,16(3):253-255
Synchronization of CO2 and red HeNe laser beams have been achieved by using a CO2 laser to quench the ferrimagnetic Faraday effect in thin films of(CO, Cr, Fe)3 O4 and (CO, Cr, Fe)3 O4 which have a large Faraday effect at 6328 Å switching occurs in subnanosecond times. 相似文献
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An extremely simple, but highly effective method of frequency stabilisation of HeNe is demonstrated. It allows production of frequency stabilities in the sub-(parts in 109) region without external optical resonators, and without modulation signals to determines relative extrema of the laser output signal (Lamb dip). The principle of regulation is explained, and measured data are presented, which were obtained by heterodyning two independently `self?-frequency-stabilised HeNe lasers at 1.52?m. 相似文献
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The linewidth of a 1.5 ?m semiconductor laser has been reduced from > 1 GHz to < 1.5 MHz by injection locking the laser to the low-power narrow-linewidth output from an HeNe laser operating at 1.523 ?m. A collimated-beam power of 750 ?W was obtained in the injection-locked semiconductor laser mode. 相似文献