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1.
Guozong Zheng Genbo Su Xinxin Zhuang Guohui Li Jiancheng Wang Zhengdong Li 《Crystal Research and Technology》2010,45(2):145-148
KDP crystals were rapidly grown from solutions doped with different Nd3+ concentrations. During the growth process, “foggy” inclusions were selectively captured in the pyramidal sector of KDP crystal and hourglass shaped crystals were obtained. It is found that the nonuniform distribution of Nd3+ ions causes remarkable differences in optical quality between prismatic and pyramidal sectors. With increasing Nd3+ concentration, the optical quality is greatly decreased for pyramidal sectors, while the change is not so obvious for prismatic sectors. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
2.
Guozong Zheng Genbo Su Xinxin Zhuang Xiuqin Lin Zhengdong Li 《Crystal Research and Technology》2008,43(8):811-816
KDP crystals were rapidly grown from solution doped with different Ba2+ concentrations. The effects of Ba2+ on the growth rate, morphology and quality of KDP crystals were discussed. Significant changes in shapes and volume of the grown crystals have been observed. During the growth process, defect region expands gradually with the increasing Ba2+ concentration. Samples were cut from different parts of the as‐grown crystals for investigating the optical quality, including transmission spectrum, scattering centers. Through comparison, it is found that the nonuniform distribution of Ba2+ ions causes remarkable difference in optical quality between prismatic and pyramidal sectors. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
3.
Single crystals of calcium iodate, monohydrate [Ca(IO3)2, H2O] have been grown by gel technique. Prismatic, prismatic pyramidal, needle shaped and hopper crystals were obtained. These crystals were also grown by doping impurities such as copper and iron. Kinetics of growth parameters was investigated. Structural analysis was carried out by using X‐ray powder diffraction method. Microtopographical study of the habit faces, such as prismatic and pyramidal, of as grown crystals was carried out. Some surface structures are reported. These crystals were etched by various etchants and appropriate etchant is reported. 相似文献
4.
受到晶体尺寸以及非线性光学性能的影响,目前可供选择的非线性晶体非常有限。DKDP晶体作为传统大尺寸光电材料,在光参量啁啾脉冲放大(OPCPA)装置中得到了应用。高氘化的DKDP晶体有更好的光学性能,然而生长出高氘化DKDP晶体对生长环境等有更加严格的要求。本文通过改良的原料合成罐以及生长槽,采用点籽晶快速生长法成功生长出高氘DKDP晶体。按照Ⅰ类(θ=37.23°, φ=45°)切割方式制备样品,并对其氘含量、透过率、光学均匀性以及晶体激光损伤阈值进行测试。实验结果表明,晶体的平均氘含量达到98.49%,在可见-近红外波段下具有较宽的透过波段和较高的透过性能。R-on-1的测试结果显示,在3 ns、527 nm条件下,DKDP晶体的激光损伤阈值达到了19.92 J/cm2。晶体光学均匀性均方根达到了1.833×10-9,表明晶体具有良好的光学均匀性。 相似文献
5.
通过传统降温法生长了不同EDTA和KCl剂量掺杂的KDP晶体,并观察了晶体的光散射情况,测定了晶体柱区样品的透过率和晶体中Fe、Cr、Cl三种杂质元素的含量,结果表明:低浓度的EDTA(0.01 mol;)和KCl(<1.5 mol;)掺杂可以提高晶体的透过率,但高浓度掺杂(0.01 mol;EDTA, 2.0 mol; KCl)会导致晶体散射严重,透过率降低,KCl浓度达到2.5 mol;后晶体生长受到抑制,晶体缺陷严重;晶体中铁Fe3+、Cr3+的总含量随着掺杂浓度的增加而减少,晶体中并没有发现Cl元素存在. 相似文献
6.
A. P. Voronov G. N. Babenko V. M. Puzikov A. D. Roshal’ V. I. Salo 《Crystallography Reports》2008,53(4):708-712
The features of doping of KDP crystals with cerium ions and organocerium complexes with alizarin complexon and arsenazo III have been investigated. It is established that “direct” doping by introducing cerium salts into the initial solution cannot be implemented. The effect of organometallic complexes of cerium on the crystal growth has been studied. Organocerium complexes predominantly enter the prismatic or pyramidal growth sectors. It is shown that the complex arsenazo III + Ce blocks the growth of the prismatic sector. Cerium-doped KDP crystals exhibit a photoluminescence band peaking at the wavelength λmax= 350 nm. 相似文献
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Y.‐J. Fu Z.‐S. Gao S.‐L. Wang Y.‐P. Li H. Zeng Ai‐D. Duan J.‐P. Luo 《Crystal Research and Technology》2000,35(2):177-184
Phosphite, which often exists in growth solutions obtained directly from commercial P2O5 , was found to have significant inhibiting effects on the growth of pyramidal face of KDP crystals. K(DxH1‐x)2PO4 (referred to as DKDP) crystals with different deuterium fraction x were grown and the optical performances were investigated. The absorption coefficients at 1.05 μm decreases monotonically with the increase of x. The transmission threshold shift from 1.65μm at x=0 to 2.10 μm at x=0.96. The high temperature phase transition temperature and latent heat were measured using the method of differential scanning calorimetry (DSC). Thermal conditioning experiments were carried out at 180°C and 140°C for KDP and DKDP, respectively. After conditioning, a different degree of improvement was observed in the optical homogeneity of the samples, while the laser damage threshold and light absorption coefficient showed no significant change. 相似文献
9.
A. P. Voronov V. I. Salo V. M. Puzikov V. F. Tkachenko Yu. T. Vydaĭ 《Crystallography Reports》2006,51(4):696-701
The conditions for the growth of potassium dihydrogen phosphate (KDP) and ammonium dihydrogen phosphate (ADP) crystals with concentrations of the thallium activator in the initial solution of 0.01, 0.1, and 1.0 wt % are investigated. It is shown that the character of incorporation and distribution of thallium in the KDP and ADP lattices is limited, apparently, by the difference in the ionic radii of K+, NH 4 + , and Tl+ cations and the charge state of prismatic {100} and pyramidal {101} growth planes. Doping of KDP and ADP with thallium (to 0.1 and 1.0 wt %, respectively) does not deteriorate the structural quality of these crystals. The dependence of the lattice parameters a and c on the thallium impurity concentration is investigated. The absorption bands of thallium in the KDP:Tl+ and ADP:Tl+ crystals peak at 218 and 215 nm, respectively, while the photoluminescence band peaks at 280 nm for both types of crystals. The relative light yield upon excitation of scintillations by α particles (Pu239) and β particles (Bi207) is measured. 相似文献
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Yu. Velikhov I. Pritula I. Ganina M. Kolybayeva V. Puzikov A. N. Levchenko 《Crystal Research and Technology》2007,42(1):27-33
Potassium dihydrogen phosphate (KDP) crystals doped with xylenol orange (XO) and methylthymol blue (MTB) are grown from aqueous solutions by the method of solvent evaporation at room temperature under the conditions of natural convection and by the method of temperature lowering. Studied is the influence of the mother solution acidity on the character of the crystal coloration. The color and coloration intensity of the grown crystals are shown to strongly depend on the solution's pH. It is revealed that the crystal habit changes in the presence of organic dyes. The optical transmission spectra and the luminescence spectra of KDP:XO solutions and of the grown crystals are measured. The effect of thermal treatment and UV‐irradiation on the coloration stability of the crystals is studied. It is found that the laser damage threshold in the prismatic impurity rich colored sectors of KDP:XO is the same as that in the prismatic sectors of pure KDP crystals. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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B. B. Parekh V. S. Joshi V. Pawar V. S. Thaker M. J. Joshi 《Crystal Research and Technology》2009,44(1):31-35
A novel method of growing calcium tartrate single crystals was developed in which the crystals were hanging freely in solution assisted by fine filaments of fungi (Aspergillums niger). Spores of A. niger were inoculated and allowed to grow in the supernatant solution of calcium chloride and tartaric acid (1:1) on the silica hydro‐gel impregnated with orthophosphoric acid. Transparent, prismatic, calcium tartrate crystals were grown hanging in the filamentous network of the fungi after 10 days in the supernatant solution. This network of the mycelium facilitated and mimicked the gel. The grown crystals were identified as calcium tartrate trihydrate and characterized by powder XRD, FTIR and TGA. This technique provides an alternate and a novel technique to grow crystals. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
14.
The effects of Bi impurity on the morphology and growth mechanism of (physical) vapor-deposited Cd crystals were investigated. Scanning electron microscopic observation revealed, for the first time, hexagonal prismatic Cd crystals which were grown on the Bi contaminated pyrex glass tube wall. This kind of morphology does not appear in the case of pure Cd without the impurity Bi. The top of the hexagonal prismatic crystal was usually rounded hemispherically. X-ray microprobe investigations showed that the tip of the crystals contained about 57 wt% Bi. It was concluded that the Cd hexagonal prismatic crystals grow by the mechanism of vapor-liquid-solid with the impurity Bi. 相似文献
15.
Zhong De‐Gao Teng Bing Wang Shu‐Hua Jiang Xue‐Jun Li Ming He Lin‐Xiang Huang Wan‐Xia 《Crystal Research and Technology》2009,44(9):925-929
Mixed crystals of potassium dihydrogen phosphate and ammonium dihydrogen phosphate were grown onto point seeds by the method of temperature reduction. It was found that the regeneration process of z‐cut point seeds became more and more difficult with increasing KH2PO4 concentration in the solution mixture. The interior stress and cracking of the mixed crystals were analyzed by synchrotron X‐ray topography. Large numbers of stress stripes were found at the seed and sectors boundaries. The lattice parameters of the pyramid and prismatic sectors of the prepared mixed crystal were calculated according to the X‐ray diffraction patterns. With solution containing 8 mol % KH2PO4, the lattice volumes of the prismatic sector of the mixed crystal were 1.3% larger than that of the pyramid sector of the crystal. Chemical etching revealed microcracks with length of hundreds of microns in the mixed crystals, which tended to spread and led to crystal cracking. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
16.
The technique and results of hydrothermal growth of single crystals of the high-pressure phase of α-PbO2 are described. Dark brown crystals of predominantly prismatic habit with characteristic sizes of 550 × 100 × 150 μm3 were obtained at p = 4 GPa by cooling an aqueous solution in the temperature range t = 600–300°C. 相似文献
17.
S. K. Geetha R. Perumal S. Moorthy Babu P. M. Anbarasan 《Crystal Research and Technology》2006,41(3):221-224
Potassium hydrogen phthalate (KAP) single crystals were grown by slow evaporation and slow cooling techniques. The growth procedure like temperature cooling rate, evaporation rate, solution pH, concentration of the solute, supersaturation ratio etc., has been varied to have optically transparent crystals. Efforts were made to dope the KAP crystals with rubidium, sodium and lithium ions. The dopant concentration has been varied from 0.01 to 10 mole percent. Good quality single crystals were grown with different concentrations of dopants in the mother phase. Depending on the concentration of the dopants and the solution pH value, there is modification of habit. Rubidium ions very much improve the growth on the prismatic faces. The transparency of the crystals is improved with rubidium and sodium doping. The role of the dopants on the non‐linear optical performance of KAP indicates better efficiency for doped crystals. The grown crystals were characterized with XRD, FT‐IR, chemical etching, Vickers microhardness and SHG measurements. The influence of the dopants on the optical, chemical, structural, mechanical and other properties of the KAP crystals was analysed. © 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim 相似文献
18.
Zhong De‐Gao Teng Bing Dong Sheng‐Ming Wang Qing‐Guo Zhao Yan‐Shuai Huang Wan‐Xia Yu Tao 《Crystal Research and Technology》2009,44(5):500-504
Solubility curves of KDP (KH2PO4) in solutions with different pH values were measured. It was found that the solubility of KDP crystal increased with the reduction pH value of solution. Transparent KDP crystal was grown from solution with 1.5 pH by point seed. Chemical etching experiments revealed that pyramid sector of the crystal displayed more growth defects. Growth defects, such as growth striation and inclusion, were analyzed by white‐beam synchrotron radiation X‐ray topography. The reasons for the formation of these growth defects were discussed. Transmittance spectra test of both prismatic sector and pyramidal sector was performed. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
19.
T. I. Dyuzheva L. M. Lityagina N. A. Nikolaev B. N. Martynov N. A. Bendeliani 《Crystallography Reports》2006,51(2):342-343
Single crystals of the high-pressure ?-FeOOH phase are grown from an aqueous solution at p = 7 GPa in the temperature range 580–350°C. Dark brown crystals of prismatic habit are obtained that have characteristic sizes of 0.1 × 0.1 × 0.7 mm. A region of the t-x phase diagram of the H2O-Fe2O3 system at p = 7 GPa is constructed on the basis of the data obtained. 相似文献
20.
S. Veintemillas Verdaguer 《Journal of Crystal Growth》1987,80(2):289-297
KDP crystals grown from boiling solutions present well developed prismatic sectors and show a good crystalline quality while being obtained at high growth rates. 相似文献