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rapid growth of a long-seed KDP crystal

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High Power Laser Science and Engineering 2020年第1期8卷 37-41页

作者： Duanyang Chen Bin Wang Hu Wang Xiangyu Zhu Ziyuan Xu Yuanan Zhao Shenghao Wang Kaizao Ni Lili Zheng Hui Zhang Hongji Qi Jianda Shao Key Laboratory of Materials for High Power Laser Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China School of Aerospace Engineering Tsinghua UniversityBeijing 100084China Department of Engineering Physics Tsinghua UniversityBeijing 100084China

To reduce the seed length while maintaining the advantages of the cuboid KDP-type crystal,a long-seed KDP crystal with size 471 mm×480 mm×400 mm is rapidly *** almost the same high cutting efficiency to obtain third harmonic generation oriented samples,this long-seed KDP-type crystal can be grown with a shorter seed than that of the cuboid KDP-type *** full width at half maximum of the high-resolution X-ray diffraction of the(200)crystalline face is 28.8 arc seconds,indicating that the long-seed KDP crystal has good crystalline *** the wavelength range of 377–1022 nm,the transmittance of the long-seed KDP crystal is higher than 90%.The fluence for the 50%probability of laser-induced damage(LID)is 18.5 J/cm^2(3 ns,355 nm).Several test points survive when the laser fluence exceeds 30 J/cm^2(3 ns,355 nm),indicating the good LID performance of the long-seed KDP *** present,the growth of a long-seed DKDP crystal is under way.

关键词： KDP crystal long-seed rapid growth

rapid growth of nickel dendrite in highly undercooled Ni-Mo alloys

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Science China(Technological Sciences) 2003年第6期46卷 593-606页

作者：姚文静魏炳波 Laboratory of Materials Science in Space Department of Applied PhysicsNorthwestern Polytechnical UniversityXi'an 710072China

Ni-39.3%Mo, Ni-45%Mo hypoeutectic alloys and Ni-47.7%Mo eutectic alloy have been rapidly solidified with different droplet sizes by containerless processing in a drop tube. For Ni-39.3%Mo hypoeutectic alloy, which corresponds to the maximum solid solubility of nickel phase, the solidification microstructure is characterized by nickel dendrite plus (Ni+NiMo) eutectic struc-ture. The undercooling of this alloy up to 182 K has been realized in the experiments. With an in-crease in undercooling, the dendritic microstructure is refined. The microstructural evolution of primary Ni phase in Ni-45%Mo hypoeutectic alloy evolves from remelted dendrite to equiaxed grains, whereas Ni-47.7%Mo eutectic alloy exhibits a structural transition from lamellar eutectic to anomalous eutectic. Theoretical analyses indicate that, for Ni-39.3%Mo, Ni-45%Mo and Ni-47.7%Mo alloys, the nickel phase shows a transition from solutal-diffusion-controlled growth to thermal-diffusion-controlled growth at undercoolings of 66.6, 81.9 and 85.0 K. The critical transition temperature decreases with a reduction in the nickel content.

关键词： dendrite rapid growth drop tube undercooling Ni-Mo

rapid growth of primary dendrite in highly undercooled copper-antimany alloy

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Progress in Natural Science:Materials International 2002年第12期12卷 57-61页

作者： YAO Wenjing , CAO Chongde and WEI Bingbo(Laboratory of Materials Science in Space, Department of Applied Physics, Northwestern Polytechnical University, Xi’an 710072, China) Laboratory of Materials Science in Space Department of Applied Physics Northwestern Polytechnical University Xi'an 710072 China

The droplets of Cu-11wt. %Sb hypoeutectic alloy have been rapidly solidified during containerless processing in a 3 m drop tube. The undercooling and cooling rates are estimated, and both play a dominant role in the dendritic growth of primary Cu phase. Undercoolings up to 200 K (0. I&TL, where TL is the liquidus temperature) have been obtained in the experiment. With the increase of undercooling, the microstructural evolution of primary Cu phase proceeds from remelted dendrites to the equiaxed grains. A coarse dendritic grain microstructure can form in the undercooling range of 61 - 102K and at cooling rates of 1.35X 102-2.66X 103K/s. The seg-regationless solidification of Cu-llwt. %Sb hypoeutectic alloy occurs when undercooling is more than 176 K. The growth of primary Cu phase is mainly controlled by solute diffusion.

关键词： rapid growth undercooling copper dendrlte drop tube.

Variation analysis of growth traits of four poplar clones under different water and fertilizer management

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Journal of Forestry Research 2020年第1期31卷 45-55页

作者： Ammar Khalil Mohamed Ahmed Luping Jiang Fang Wang Song Chen Xueyan Zhou Xiaona Pei Xiyang Zhao Guanzheng Qu State Key Laboratory of Tree Genetics and Breeding Northeast Forestry UniversityHarbin 150040People’s Republic of China Faculty of Forest Science and Technology University of Gezira22212 MadaniAbu HarazSudan

To determine appropriate quantities of water and fertilizer required for early growth of hybrid poplar cuttings,we recorded the growth traits of four clones grown under four factors(irrigation and nitrogen,phosphorus,and potassium fertilizers),each with four levels,using an orthogonal experimental design.A logistic model was used to estimate growth in *** growth curves for tree height were sigmoid,and the model R^2 values were greater than 0.9,which indicated that the fit was highly *** results for tree height and basal diameter indicated that all sources of variance showed significant differences(prapid growth period of poplar clones was 131 d,and the highest average increment in tree height during the rapid growth period was 138.78 *** highest average tree height for all clones under each factor was 219,210.51,200,and 201 cm when treated with either 1200 mL of water applied every third day,3 g of nitrogen,0 g of phosphorus,or 0 g of potassium,*** most suitable treatment for the early growth of hybrid poplar cuttings,as suggested by the developed logistic model,was 1200 mL of water applied every third day and three applications of 1 g nitrogen(in the form of CH4N2O).

关键词： Fertilizer management growth trait Logistic model Poplar rapid growth Variation

A MODEL FOR BAINITIC TRANSFORMATION KINETICS WITH PARABOLIC NUCLEATION RATE

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Acta Metallurgica Sinica(English Letters) 2001年第1期14卷 63-71页

作者： C.C. Liu, K.F. Yao and Z Liu (Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China) Dept. of Mech. Eng. Tsinghua Univ. Beijing 100084 China

Based on the assumptions of parabolic variation of nucleation rate versus time and transformation kinetics depending mainly on nucleation rate, a different model for bainitic transformation kinetics in hypoeutectoid steels was established. And this model was proved to be effective in the description of bainitic transformation by comparison with the result of conventional Avrami equation.

关键词： bainitic transformation kinetics parabolic nucleation rate rapid growth

阴离子杂质对KDP晶体生长习性的影响及快速生长研究

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人工晶体学报 2000年第S1期29卷 102-页

作者：傅有君王圣来孙洵李毅平曾红罗建平段爱东高樟寿山东大学晶体材料国家重点实验室济南250100

Great interest is being focused on the growth technique of KDP crystal,the first choice material for the fabrication of frequency converter and electro optic switcher used in the studies of inertial confinement fusion (ICF).To reduce the cost of growth,scientists are endeavoring to promote the growth ***“point seed” method is one of rapid growth techniques recently developed by Lawrence Livermore National *** the former technique,crystals are grown in all three directions at an averaged rate of 10 15mm/day. Impurities are regarded as one of the factors to inhibit the growth *** is generally accepted that high valence cationic ions,such as Fe 3+ ,Cr 3+ ,Al 3+ ,etc,are easy to be adsorbed on the prismatic faces and inhibit their *** anions,especially those have ability to form strong hydra bond,such as phosphate derivatives (polyphosphate,metaphosphate,pyrophosphate,etc) have significant inhibiting effects on the growth of KDP pyramidal *** is suggested that the H bonding is the key interaction force between the growing surface and the impurities.

关键词： KDP crystal nonlinear optical crystal crystal growth from salution rapid growth

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大尺寸KDP晶体生长

人工晶体学报 2000年第S1期29卷 116-117页

作者： GAO Zhang-shou LI Yi ping ZENG Hong WANG Sheng lai SUN Xun State Key Lab.of Crystal Materials Shandong UniversityJinan 250100China

KDP and its deuterated analog DKDP (K (D x H 1- x ) 2PO 4) are the first ch oice materials in the fabrication of optical switcher and frequency converter fo r inertial confinement fusion *** the past years,the growth technique has b een d eveloped *** aperture crystals can be grown with various methods,such as,temperature decreasing,solution circular flow,and rapid growth method,which i ntend to reduce the cost of production and satisfy the requirement of *** to rapid growth method,much attention has been paid to solution stability and the K DP crystal qualities of this method which has been proved that high speed can be *** has grown KDP crystal with dimension of 57mm×57mm×55mm,260 kil ogram in 59 *** method is very different from conventional method for grow ing KDP crystal in three directions *** addition to the growth of the pyramidal faces,rapid crystallization from supersaturated solution results in si gnificant growth of prismatic *** of growth solution and incorporat ion of metal impurities will occur in the prism sector as prism extends very muc h by this *** growth needs high supersaturation(10%—30%),so the grow th condition,such as ,raw materials,apparatus,temperature lowing proceed should be controlled very *** order to improve the utilization of KDP crystal g rown by point seed method,we developed 4 vessels circular technique on the bas e of 3 vessels circular technique recently.

关键词： KDP crystal nonlinear optical crystal rapid growth crystal growth from solution

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从高速增长走向和谐发展的中国经济

国民经济管理 2007年第11期

作者：陈佳贵黄群慧张涛

本文将中国经济快速增长的影响因素归结为7方面：工业化和城市化的快速推进为中国经济长期高速增长提供了充足动力：大众消费时代来临，消费需求成为支撑中国经济持续高速增长最稳定的因素：对外开放的深化，对中国经济具有重要推动作... 详细信息

本文将中国经济快速增长的影响因素归结为7方面：工业化和城市化的快速推进为中国经济长期高速增长提供了充足动力：大众消费时代来临，消费需求成为支撑中国经济持续高速增长最稳定的因素：对外开放的深化，对中国经济具有重要推动作用；高储蓄为中国经济持续高速增长提供了充足的资金保证：丰富的劳动力供给和日益提高的劳动力素质成为中国经济持续高速增长的基本要素：技术进步是中国经济持续高速增长的重要因素；“中国模式”的经济体制改革成就了中国经济的奇迹。同时，本文认为中国经济发展面临结构失衡的压力、来自分配差距扩大的压力、面临资源和环境方面的压力和人口快速老龄化的压力。综观中国经济的全局，支撑经济快速增长的因素还没有改变，只要我们认真贯彻落实科学发展观，坚持以人为本，坚持全面协调和可持续发展，认真对待、妥善处理好发展中的各种矛盾和问题，在未来10—15年时期里，中国经济继续保持7％以上的增长速度是完全可以做到的。但是，从现在所处的发展阶段和面临的问题看，今后中国最为重要、最为迫切的是要在科学发展观的统领下保持和谐发展，更加重视协调发展，更加重视经济增长的质量和效益，更加重视结构优化，更加重视深层次的改革。

关键词：中国经济高速增长和谐发展 China economy rapid growth harmonious development

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中国经济高速增长的代价分析