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Amplification effect on stimulated Brillouin scattering in the s-band forward G652 fiber raman amplifier

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Chinese Optics Letters 2005年第11期3卷 629-632页

作者：张在宣戴碧智李来晓徐海峰刘红林王剑锋李晨霞 Insoo s.Kim Optoelectronics Technology Institute China Jiliang University Hangzhou 310018 Optoelectronics Technology Institute China Jiliang University Hangzhou 310018 College of Optics and Electronics University of Shanghai for Science and Technology Shanghai 200093 Optoelectronics Technology Institute China Jiliaag University Hangzhou 310018 Optoelectronics Technology Institute China Jiliang University Hangzhou 310018 College of Optics and Electronics University of Shanghai for Science and Technology Shanghai 200093 Optical Technology research Group Korea Electrotechnology research Institute Seoul 437-808 Korea

The amplification effects on forward and backward stimulated Brillouin scattering （sBs） lines in the forward pumped s-band distributed G652 fiber raman amplifier （FrA） have been studied. There is a pump threshold power of stokes backward stimulated Brillouin scattering （B-sBs） line in the forward pumped G652 FrA, it is about 1 mW. The stokes B-sBs lines are amplified by FrA and fiber Brillouin amplifier （FBA）. The gain of amplification is given as Ga = Gr· GB where Get is raman gain and GB is Brillouin gain. In experimental work, the saturation gain of the first order stokes backward sBs line is about 58 dB and the saturation gain of 25-km G652 forward FrA is about 25 dB, so the gain of FBA is about 33 dB. The forward stimulated Brillouin scattering （F-sBs） is generated and amplified in s-band G652 FrA. The stimulated threshold powers of the forward first order stokes sBs （sB1^-）, second order stokes sBs （sB2^-）, and third order sBs （sB3） in the forward pumped FrA are 2.3, 1.6, and 1.6 mW, respectively. In experimental work, the saturation gains of sB1^-, sB2^, and sB3 are about 38, 62, and 60 dB, respectively. The saturation raman gain of 25-km G652 forward FrA is about 8.8 dB, so the Brillouin gains of sB1^-, sB2^-, and sB3 are about 29.2, 53.2, and 51.2 dB, respectively. The forward and backward cascaded sBs lines have been observed.

关键词： Light amplifiers Optical fibers Optical pumping

shipbuilding Market under New structure

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中国船检 2008年第4期 18-19页

作者： COsCO r&D Center Yang Fan

Before 1980’s,the world shipbuilding industry is vested in a structure of two poles,west Europe being one pole and Japan the other. By 1980’s,with development of shipbuilding industries in Korea and other countries,the dually-polarized situation of world shipbuilding was gradually broken and the multi-polarizing trend of development appeared. The world shipbuilding industry began to form with a quadrupole structure featuring Japan,Korea,west Europe,and China representing other countries/regions. Japan and Korea were the two powers in the quadruple. This quadrupole situation was basically maintained throughout 1980’s to 1990’s.

关键词： over shipbuilding Market under New structure

Mass stopping Power and range of Protons in Biological Human Body Tissues (Ovary, Lung and Breast)

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International Journal of Medical Physics, Clinical Engineering and radiation Oncology 2022年第1期11卷 48-59页

作者： Ahlam s. Almutairi Khalda T. Osman Department of Physics College of Science Qassim University AL-Rass Saudi Arabia Department of Physics College of Science Qassim University Buraydah Saudi Arabia

In this work, the mass stopping power and range of protons in biological human body tissues (ovary, lung and breast) were calculated at the energy ranging from 0.04 MeV to 200 MeV using the MATLAB Program. The data relating to the densities, average atomic number to mass number and excitation energy for the present tissues were collected from ICrU report 46. The mass stopping power was calculated by the Bethe formula. Moreover, the simple integration (continuous slowing down approximation) method was employed for calculating protons range at the tissues. The results of the mass stopping power versus energy and the range versus energy were presented graphically and the empirical formulae for calculating the mass stopping power and the ranges were obtained. The present results for mass stopping powers and ranges were compared with the results obtained by others. Good agreements were found between them, especially at the energy ranging from 3 to 200 MeV.

关键词： Human Body Tissues Protons range MATLAB Mass stopping Power

Calculation of Mass stopping Power and range of Protons as Well as Important radiation Quantities in some Biological Human Bodyparts (Water, Muscle, skeletal and Bone, Cortical)

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International Journal of Medical Physics, Clinical Engineering and radiation Oncology 2022年第2期11卷 99-112页

In this work, the electronic mass stopping power and the range of protons in some biological human body parts (Water, Muscle, skeletal and Bone, Cortical) were calculated in the energy range of protons 0.04 to 200 MeV using the theory of Bethe-Bloch formula as giving in the references. All these calculations were done using Matlab program. The data related to the densities, average atomic number to mass number and excitation energies for the present tissues and substances were collected from ICrU report 44 (1989). The present results for electronic mass stopping powers and ranges were compared with the data of PsTAr and good agreements were found between them, especially at energies between 1 - 200 MeV for stopping power and 4 - 200 MeV for the range. Also in this study, several important quantities in the field of radiation, such as thickness, linear energy transfer (LET), absorbed dose, equivalent dose, and effective dose of the protons in the given biological human body parts were calculated at protons energy 0.04 - 200 MeV.

关键词： Biological Human Bodyparts Protons range MatLab PsTAr Electronic Mass stopping Power LET Absorbed Dose Effective and Equivalent Dose

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G652光纤中背向自发拉曼散射的增益特性

光电子．激光 2006年第7期17卷 895-898页

作者：王剑锋张在宣徐海峰余向东 Insoo s KIM 中国计量学院光电子技术研究所浙江杭州310018 韩国电气技术研究院

讨论了背向自发raman散射脉冲在自生分布式G652光纤raman放大器中传输的增益特性。实验发现,反stokes raman(Asr)和stokes raman(sr)自生分布式脉冲光纤raman放大器的阈值抽运峰值功率是25.4 W和18.0 W。在入射功率为52 W时,Asr和sr的... 详细信息

讨论了背向自发raman散射脉冲在自生分布式G652光纤raman放大器中传输的增益特性。实验发现,反stokes raman(Asr)和stokes raman(sr)自生分布式脉冲光纤raman放大器的阈值抽运峰值功率是25.4 W和18.0 W。在入射功率为52 W时,Asr和sr的增益分别为5.0 dB和8.6 dB。放大的反stokes和stokes背向自发raman散射光时域反射(OTDr)曲线上放大的阈值时间位置随激发功率的增高前移并具有规律性。放大的Asr背向自发散射强度受光纤温度调制,具有温度效应,已应用于远程分布光纤raman温度传感器系统。

关键词： raman散射效应背向自发raman散射光纤受激raman散射(srs) 单模光纤放大的背向自发反stokes raman(Asr)散射温度效应光时域反射(OTDr)

Blue band nonlinear optics and photodarkening in silica microdevices

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Photonics research 2022年第9期10卷 2073-2080页

作者： KE TIAN JIBO YU FUCHUAN LEI JONATHAN WArD ANGZHEN LI PENGFEI WANG sÍLE NIC CHOrMAIC Okinawa Institute of science and Technology Graduate University OnnaOkinawa 904-0495Japan Key Laboratory of In-Fiber Integrated Optics of Ministry of Education College of Physics and Optoelectronic EngineeringHarbin Engineering UniversityHarbin 150001China Department of Microtechnology and Nanoscience Chalmers University of TechnologySE-41296 GothenburgSweden Physics Department University College CorkCorkIreland Key Laboratory of Optoelectronic Devices and systems of Ministry of Education and Guangdong Province College of Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China

There are extensive studies to date on optical nonlinearities in microcavities at the near and mid-Ir *** this research into the visible region is equally ***,we demonstrate a directly pumped,blue band Kerr frequency comb and stimulated raman scattering(srs)at 462 nm in a silica nanofiber-coupled whispering gallery microcavity ***,due to the high optical intensities achieved,photodarkening is unavoidable and can quickly degrade the optical quality of both the coupling optical nanofiber and the microcavity,even at very low pump ***,stable hyperparametric oscillation and srs are demonstrated in the presence of photodarkening by taking advantage of in-situ thermal *** work highlights the challenges of silica-based,short wavelength nonlinear optics in high-quality,small mode volume devices and gives an effective method to overcome this apparent limitation,thus providing a baseline for optics research in the blue region for any optical devices fabricated from silica.

关键词： pumped pump scattering

sutureless end-to-end bowel anastomosis in rabbit using low-power CO_2 laser

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World Journal of Gastroenterology 2000年第4期6卷 557-560页

作者： Zhong rong Li Yong Long Chi run Cong Ke Department of Pediatric surgery,Yu-Ying Children’s Hospital,Wenzhou Medical College,Wenzhou 325027,Zhejiang Province,China 温州医学院浙江温州

The use of laser energy to weld biological tissues and produce sutureless anastomosis has its advantages over conventional silk-sutured anastomosis since it was reported in small vessels[1] and fallopian tubes[2], in the late 1970s. since then, more investigators have welded a larger variety of tissues[3-13] and have expanded its application to welding trials of entertomies of rabbit and rat small intestine[14-17] sauer et al[18] reported results from Nd: YAG laser in reconstruction of end-to-end welding in rabbit small intestine. recently, controlled temperature during YAG and argon laser-assisted welding of entertomies of rabbit and rat was implemented to eliminate exponential increases in the rate of denaturation associated with rapidly increasing temperature[19，20]. Yet there was no report of sutureless end-to-end bowel anastomosis using low-power CO2 laser. This is a report of a circumferential end-to-end laser welding bowel anastomosis in rabbit by using 3 different CO2 laser powers to explore the feasibility of CO2 laser welding of a circumferential intestinal tissue and to determine the optimal laser-welding parameter. Then the appropriate CO2 laser power was chosen to weld bowels in rabbit and its long-term healing effect was evaluated.

关键词： laser surgery anastomosis surgical intestine small animals laboratory microscopy electron rabbits

How should Police respect and Protect Human rights?

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The Journal of Human rights 2007年第2期6卷 34-37页

作者： WANG XIUHONG Beijing People’s Police College. Beijing People's Police College

All people are equal before law and human rights must be respected and guaranteed. This is an established principle in China in bringing about a harmonious society. But how should police respect and ensure human fight... 详细信息

关键词： Pr How should Police respect and Protect Human rights

Progress of LHCD and IBW Heating Experiments on HT-7 Tokamak

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Plasma science and Technology 2009年第4期11卷 381-384页

作者：高翔赵燕平袭先祖胡立群单家方 K.TOI s.MOrITA 刘瑾许平徐强刘海庆杨建华万宝年李建刚 Institute of Plasma Physics Chinese Academy of Sciences National Institute for Fusion science Yunnan University

Experimental progress of lower hybrid current drive （LHCD） and ion Bernstein wave （IBW） heating was achieved significantly in HT-7. Long pulse plasmas, up to 400 s, were obtained by LHCD. High power lower hybrid wave （LHW）, with PLHW of 800 kW at 2.45 GHz, was launched and the current drive efficiency was studied for different wave powers. Electron temperature and Zeff were measured in LHCD discharges. Heating experiment and recent results of high power ion Bernstein wave, with PIBW of 600 kW at 27 MHz, were summarized.

关键词： LHCD IBW heating long duration