Based on a specially designed optical structure, an efficient cascaded third-harmonic-generation（THG） output of a 1064-nm, pico-seconds pulse laser is successively realized by using an NH_4H_2PO_4（ADP） crystal tha...Based on a specially designed optical structure, an efficient cascaded third-harmonic-generation（THG） output of a 1064-nm, pico-seconds pulse laser is successively realized by using an NH_4H_2PO_4（ADP） crystal that acts as the secondharmonic-generation component and sum-frequency-generation component. The maximum THG output is 1.61 mJ, and the highest conversion efficiency from 1064 nm to 355 nm reaches 35%, which are obviously superior to the results obtained using a KDP crystal under the same circumstance. The further phase-matching analysis indicates that this THG configuration of ADP crystal can be applied to various fundamental wavelengths in a range of 1 μm–1.1 μm. Compared with the previously reported KDP THG converter, which is based on a similar principle, the present ADP THG converter is favorable for large-energy, high-efficiency operation because of the larger effective nonlinear optical coefficient deffand higher laser damage threshold.展开更多
ADP (NH4H2PO4) crystals were grown through the traditional method and rapid growth technology. The optical homogeneity of rapid grown ADP crystals was analyzed by laser interferometry and X-ray topography. Laser inter...ADP (NH4H2PO4) crystals were grown through the traditional method and rapid growth technology. The optical homogeneity of rapid grown ADP crystals was analyzed by laser interferometry and X-ray topography. Laser interferometry revealed sector boundaries at which optical homogeneity decreased dramatically. The main defects that seriously reduced the optical homogeneity of the rapid grown ADP crystal were sector boundaries, growth bands and inclusions. The concentration of Fe and Cr impurities was tested by a plasma emission spectrometer. It was found that the preferential incorporation of metallic impurities into the prismatic faces resulted in high density of growth bands and inclusions, thus reducing optical homogeneity of the prismatic sector.展开更多
ADP晶体{100}面族生长的实时与非实时AFM（atomic force microscopy，AFM）研究表明，过饱和度σ处于0．005～0．04，生长温度介于293～313K之间时，晶面上观察到位错生长丘和其它晶体缺陷所形成的生长丘，晶面主要为台阶推进方式生长...ADP晶体{100}面族生长的实时与非实时AFM（atomic force microscopy，AFM）研究表明，过饱和度σ处于0．005～0．04，生长温度介于293～313K之间时，晶面上观察到位错生长丘和其它晶体缺陷所形成的生长丘，晶面主要为台阶推进方式生长；位错生长丘上空洞的出现与位错弹性理论相符；随过饱和度口降低，台阶形貌会发生相应变化；生长温度为298K时，台阶棱边能不小于6．2×10^-7／cm^2。展开更多
ADP晶体{100}面族微观形貌的非实时AFM（atomic force microscopy，AFM）成像表明，过饱和度σ=0．053时，晶面上出现二维成核生长；随σ增加至0．11，二维岛数量急剧增加，尺寸减小，分布渐趋均匀，二维成核生长逐渐增强，界面呈现出...ADP晶体{100}面族微观形貌的非实时AFM（atomic force microscopy，AFM）成像表明，过饱和度σ=0．053时，晶面上出现二维成核生长；随σ增加至0．11，二维岛数量急剧增加，尺寸减小，分布渐趋均匀，二维成核生长逐渐增强，界面呈现出由光滑向粗糙转变的特征；各二维岛形状趋近于长条形，表现出各向异性，长轴平行于[001]晶向；二维岛上有单分子高度的台阶和台阶聚并后高度为2～3nm的大台阶；二维岛间融合时取向相同；σ=0．053时，融合后所形成的较大二维岛的生长呈现出周边快中心慢的情况，将可能导致产生晶体缺陷。展开更多
In contrast with the coezyme, two coenzyme analogs, ADP-ribose and SNAD, bind non-cooperatively to D-glyceraldehyde-3-phosphate dehydrogenase (GAPDH). Palinurus versicolor (PV) GAPDH complexed with ADP-ribose and SNAD...In contrast with the coezyme, two coenzyme analogs, ADP-ribose and SNAD, bind non-cooperatively to D-glyceraldehyde-3-phosphate dehydrogenase (GAPDH). Palinurus versicolor (PV) GAPDH complexed with ADP-ribose and SNAD has been crystallized by the method of sitting-drop vapor diffusion. X-ray diffraction data analysis reveals that both crystals belong to the same space group (C2), and have similar cell dimensions: a =152.80 A, b =100.35 A, c =128.31 A, β=110.28° and a =153.41 A, b =100.51 A, c =128.44 A, β =110.48°, respectively. It is estimated that the asymmetric unit in each crystal contains 4 subunits. This is a novel crystal form which is quite different from that previously reported for holo- and apo-GAPDH from the same spurce. The result suggests that the binding of the two coenzyme analogs to GAPDH may lead to some significant conformational changes, which are different from those induced by the coenzyme binding. The self-rotation function indicates that the tetramer of these two GAPDH展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.61178060,51202129,and 91022034)the Independent Innovation Foundation of Shandong University,China(Grant No.2011GN056)the Natural Science Foundation for Distinguished Young Scholar of Shandong Province,China(Grant No.2012JQ18)
文摘Based on a specially designed optical structure, an efficient cascaded third-harmonic-generation（THG） output of a 1064-nm, pico-seconds pulse laser is successively realized by using an NH_4H_2PO_4（ADP） crystal that acts as the secondharmonic-generation component and sum-frequency-generation component. The maximum THG output is 1.61 mJ, and the highest conversion efficiency from 1064 nm to 355 nm reaches 35%, which are obviously superior to the results obtained using a KDP crystal under the same circumstance. The further phase-matching analysis indicates that this THG configuration of ADP crystal can be applied to various fundamental wavelengths in a range of 1 μm–1.1 μm. Compared with the previously reported KDP THG converter, which is based on a similar principle, the present ADP THG converter is favorable for large-energy, high-efficiency operation because of the larger effective nonlinear optical coefficient deffand higher laser damage threshold.
基金supported by the National Natural Science Foundation of China (Grant Nos. 10774081 & 10304009)the Natural Science Foundation of Shandong Province (Grant No. Y2007F16)the Fund of National En-gineering Research Center for Optoelectronic Crystalline Materials (Grant No. 2007k08)
文摘ADP (NH4H2PO4) crystals were grown through the traditional method and rapid growth technology. The optical homogeneity of rapid grown ADP crystals was analyzed by laser interferometry and X-ray topography. Laser interferometry revealed sector boundaries at which optical homogeneity decreased dramatically. The main defects that seriously reduced the optical homogeneity of the rapid grown ADP crystal were sector boundaries, growth bands and inclusions. The concentration of Fe and Cr impurities was tested by a plasma emission spectrometer. It was found that the preferential incorporation of metallic impurities into the prismatic faces resulted in high density of growth bands and inclusions, thus reducing optical homogeneity of the prismatic sector.
文摘ADP晶体{100}面族生长的实时与非实时AFM（atomic force microscopy，AFM）研究表明，过饱和度σ处于0．005～0．04，生长温度介于293～313K之间时，晶面上观察到位错生长丘和其它晶体缺陷所形成的生长丘，晶面主要为台阶推进方式生长；位错生长丘上空洞的出现与位错弹性理论相符；随过饱和度口降低，台阶形貌会发生相应变化；生长温度为298K时，台阶棱边能不小于6．2×10^-7／cm^2。
文摘ADP晶体{100}面族微观形貌的非实时AFM（atomic force microscopy，AFM）成像表明，过饱和度σ=0．053时，晶面上出现二维成核生长；随σ增加至0．11，二维岛数量急剧增加，尺寸减小，分布渐趋均匀，二维成核生长逐渐增强，界面呈现出由光滑向粗糙转变的特征；各二维岛形状趋近于长条形，表现出各向异性，长轴平行于[001]晶向；二维岛上有单分子高度的台阶和台阶聚并后高度为2～3nm的大台阶；二维岛间融合时取向相同；σ=0．053时，融合后所形成的较大二维岛的生长呈现出周边快中心慢的情况，将可能导致产生晶体缺陷。
基金supported by the National Natural Science Foundation of China(10979029,11204148 and 51172111)the Fundof National Engineering Research Center for Optoelectronic Crystalline Materials(2007k08)
文摘In contrast with the coezyme, two coenzyme analogs, ADP-ribose and SNAD, bind non-cooperatively to D-glyceraldehyde-3-phosphate dehydrogenase (GAPDH). Palinurus versicolor (PV) GAPDH complexed with ADP-ribose and SNAD has been crystallized by the method of sitting-drop vapor diffusion. X-ray diffraction data analysis reveals that both crystals belong to the same space group (C2), and have similar cell dimensions: a =152.80 A, b =100.35 A, c =128.31 A, β=110.28° and a =153.41 A, b =100.51 A, c =128.44 A, β =110.48°, respectively. It is estimated that the asymmetric unit in each crystal contains 4 subunits. This is a novel crystal form which is quite different from that previously reported for holo- and apo-GAPDH from the same spurce. The result suggests that the binding of the two coenzyme analogs to GAPDH may lead to some significant conformational changes, which are different from those induced by the coenzyme binding. The self-rotation function indicates that the tetramer of these two GAPDH
