共查询到20条相似文献,搜索用时 62 毫秒
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本文通过差热分析(DTA)和X射线粉末衍射(XRD)方法研究了赝二元系LiFCaAlF5的相平衡关系,该赝二元系在LiF:CaAlF5=1:1处形成一致融熔化合物LiCaAlF6,其熔点为814℃,并分别在LiF ̄LiCaAlF6和LiCaAlF6 ̄CaAlF5区域形成两个共晶体系,采用坩埚下降法生长出氟化物激光晶体Cr^3+:LiCaAlF6。 相似文献
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尽管升华方法在除去氧化物方面很有成效,但也必须注意ZrF4和HfF4的水解温度和脱水温度.由于升华方法不能有效地除去象FeF3等氟化物杂质.作者根据FeF63-,CoF63-是属于外轨道络合物,它们是不稳定的和容易离解出Fe3+和CO3+,同时FeZrF6·6H2O也易于离解出Fe2+,以致使(NH4)3ZrF7和(NH4)3HfF7可以用DDTC-CHCl3,在pH3~3.5的有效萃取成为可能.在ZrF4-HfF4的二元组分系统中,它们的升华、凝华过程是遵循图2的相平衡规律进行的.用XRD检测升华产品,为无水单斜态的ZrF4或HfF4晶体,用GFAAS检测,升华前后Fe含量各自为0.8ppm和0.5ppm,批生产量250g. 相似文献
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3.2美能达AF85mm f/1.4G 这款镜头镜头号为:20801191。最大光圈F1.4,采用浮动对焦设计,圆形9瓣光圈叶片,有特宽的橡胶对焦环、焦点固定按钮。 主要性能规格 焦距:85mm光圈范围: F1.4至F22镜头组成: 6组7片视场角: 28°30’最短摄影距离: 0.85m最大摄影倍率: 0.128滤镜尺寸: 72mm外形尺寸: 78mm(最长)× 72. 5mm(直径)重量: 550g 焦距实测值为85.75mm。与标称值的相对误差为0.9%。 摄影分辨率测试条件同上,该款镜头的分辨率如表2。… 相似文献
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Two new barium indium phosphates BaIn2P4O14 and Ba3In2P4O16 were synthesized by high temperature solution growth method and structurally characterized by single crystal X-ray diffraction analysis. They represent first compounds in the Ba-In-P-O systems. BaIn2P4O14 and Ba3In2P4O16 display different types of 3D architectures. The projections of both structures concern about the existence of the intersecting tunnels. In compound BaIn2P4O14, the tunnels are built up of the corner-sharing InO6 octahedra and P2O7 groups, whereas in compound Ba3In2P4O16, they are formed by corner sharing of PO4 tetrahedra and InO6 octahedra. The electronic band structure calculations of two compounds have been performed with the density functional theory method. The study of calculations and optical diffuse reflectance experimental results show both compounds are insulators with direct band-gap. 相似文献
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The far-infrared spectra of a Bi2Sr2CaCu2O8 single crystal at 2.7 and 298 K is reported for the spectral range of 30–350 cm–1. Several characteristic bands of Cooper pairs are found at 2.7 K in the far infrared region, and accompanied by low-energy side bands. 相似文献
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Single crystals of Y2Cu2O5 were obtained in the flux growth process by controlled heating of a mixture of Y2O3, BaO, and CuO in a molar ratio of 1820. These crystals were analyzed by a single-crystal X-ray diffraction analysis. The crystal contains polymeric chains of Cu2O5 interspersed by yttrium ions surrounded by octahedral arrangements of oxygen atoms. Crystal data: space group=Pna21,a=10.799(2) Å,b=3.4990(5) Å,c=12.459(2) Å,Z=4, 380 reflections,R=0.026,R
w=0.030. 相似文献
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J. Fernndez M. A. Illarramendi I. Iparraguirre I. Aramburu J. Azkargorta M. Voda M. Al-Saleh R. Balda 《Optical Materials》2004,26(4):483
In this paper we report an experimental demonstration of broadband wavelength self-tuning in Rb5Nd(MoO4)4 laser crystal (RNM) together with the theoretical treatment which explains the system behaviour based on its birefringent properties. The self-frequency tuning in RNM was obtained by inserting an a-cut plate inside the laser resonator close to the Brewster's angle. At a given position of the crystal plate, when the wavelength of the oscillating mode corresponds to an integral number of full-wave retardation in the plate, the laser operates in the p polarization of the Brewster surface with no losses. The experimental self-frequency tuning of the laser emission along the free spectral range of the RNM crystal (1062.94–1067.84 nm) was obtained by rotating the birefringent gain plate in its own plane. To investigate the tuning characteristics of the spectral filter, we have used the Jones-vector formalism. The calculated wavelength-selective tuning matches the experimental observations. 相似文献
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自变频激光晶体Nd3+:GdAl3(BO3)4的研究 总被引:1,自引:0,他引:1
采用熔盐法生长出尺寸为30mm的Nd3+:GdAl3(BO3)4优质晶体,进行了吸收光谱和荧光光谱的测定研究,计算得到晶体发射截面为σe1061.9=2.9×10-19cm2和σe1338mm=5.5×10-20cm2.采用染料激光器作为泵浦源,对晶体进行了自变频激光实验研究,在紫外可调谐(378-382nm)、绿光531nm、蓝光(436-443nm)、红光(669nm)和红外可调谐(1305-1365nm)波段实现了激光输出,输出的最大功率分别为:105μJ/脉冲、119.5μJ/脉冲、445μJ/脉冲、19μJ/脉冲和31μJ/脉冲. 相似文献
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采用固态反应方法合成了有序的铁基硼磷酸盐Fe2BP3O12,用X射线粉末衍射方法精修了其晶体结构,属三方晶系,空间群为P3,a=8.02703(6)A,c=7.40168(9)A,V=413.02(1)A3,Dx=3.2758(1)(g/cm3),Z=2,对于55个参数,用188条衍射线及18001个衍射强度全谱数据点精修到R(I)=6.35%,R(p)=15.36%,所对应的R(dbw)=10.12%.B原子具有三角形氧配位,P和Fe的氧配位分别是四面体和八面体.Fe的两配位八面体共面形成新结构单元,BO3三角形联接磷氧和铁氧多面体形成三维结构.对比同构的铬硼磷酸盐,此化合物期望具有类似的非线性光学及其它非线性物理性质. 相似文献
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采用中频感应提拉法生长出尺寸为φ60mm×110mm的CeLu1.6Yo.4SiO5(LYSO)晶体,与LSO晶体相比,LYSO晶体的优势是提高了晶体质量、降低了熔点和原料成本等.在室温下测试了LYSO晶体的透过光谱、激发光谱和发射光谱,结果表明Y的加入使LSO晶体的吸收边向短波方向偏移.Ce3+的4f1→5d1跃迁吸收导致紫外区产生三个吸收带.发射光谱具有Ce3+典型的双峰特征,经Gaussian多峰值拟合,双峰395nm和418nm归属于Ce1发光中心,而435nm的发光峰与Ce2发光中心有关. 相似文献