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Synthesis of high quality type-Ib diamond crystals in carats grade

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Chinese Science Bulletin 2010年第14期55卷 1372-1375页

作者： XIAO HongYu JIA XiaoPeng MA HongAn li shangsheng li Yong ZHAO Ming State Key Laboratory of Superhard Materials Jilin University Changchun 130012 China

High quality type-Ib tower-shape gem-diamond crystals in carats grade were synthesized in cubic anvil high pressure apparatus (SPD-6×1200) at 5.4 GPa and 1250-1450°C. The relationship between the growth time and the weight of growth diamond has been gained. The faces of {110} and {113} were found in the synthetic diamond crystals frequently. We found that the relative growth rate of {113} face was descending with the increase of growth temperature, and that of {110} face had no obvious change with the increase of the growth temperatures and the growth time. In the work, the crystal defects were studied carefully, and the reasons for the appearance of the defects were also obtained. Some diamond crystals have been polished into the anvil of DAC (Diamond Anvil Cell) and the diamond jewelry. Compared with natural diamond crystal, synthetic diamond crystal has the merits such as small grinding quantity, low cost, etc., so it can be widely used in super high pressure field and gemstone industry.

关键词：宝石级金刚石单晶合成克拉金刚石晶体质型经济增长生长温度钻石首饰

Effects of additive boron on HPHT diamond single crystals grown by TGM

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Science China(Physics,Mechanics & Astronomy) 2011年第12期54卷 2186-2190页

作者： XIAO HongYu QIN YuKun li shangsheng liANG ZhongZhu MA HongAn JIA XiaPeng Department of Mathematics and Physics Luoyang Institute of Science and Technology Luoyang 471023 China Henan Polytechnic University Jiaozuo 454000 China State Key Laboratory of Applied Optics Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences Changchun 130033 China National Lab of Superhard Materials Jilin University Changchun 130012 China

In this work, under pressure 5.4 GPa and temperature 1250-1400°C, large gem-diamond single crystals with perfect shape and different content of additive boron were synthesized using temperature gradient method. High-purity boron powders were added as boron source into the graphite powder, and the effects of additive boron on crystal growth habit were investigated in detail. The relationship between the growth rate and the amount of additive boron was studied. The scanning electron microscopy was employed to study the morphology of boron-doped diamond crystals. Raman spectroscopy and Hall measurements were used to investigate the crystal structures and the carrier concentration, respectively. The results show that with the increase of the content of boron added into graphite powder, the crystal growth rate and the carrier concentration increase firstly, and decrease afterwards, and the zone-center phonon line at 1332 cm 1 has small shift to lower energy. The defects occur on the crystal surface when excessive boron is added in the synthesis system.

关键词： HPHT boron-doped diamond catalyst carrier concentration

Effect of additive boron on type-Ib gem diamond single crystals synthesized under HPHT

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Chinese Science Bulletin 2010年第8期55卷 677-679页

作者： MA liQiu MA HongAn XIAO HongYu li shangsheng li Yong JIA XiaoPeng National Key Laboratory of Super Hard Materials Jilin University Changchun 130012 China Institute of Material Science and Engineering Henan Polytechnic University Jiaozuo 454000 China

The boron-doped type-Ib gem diamond crystals were synthesized successfully by adding amorphous boron into a system of graphite and Kovar catalyst under high pressure and high temperature (HPHT).The effect of additive boron on type-Ib gem diamond was extensively studied including the growth characteristic,morphology and nitrogen *** synthesized boron-doped type-Ib gem diamond crystals were characterized by optical microscope (OM),scanning electron microscope (SEM) and infrared spectrometer (IR).The results show that the growth region of the {111} face becomes wide,whereas the growth region of the {100} face becomes narrow and nearly disappears as increasing additive boron in the *** crystal will be opaque and imperfect,and the concentration of nitrogen will be decreased when the boron atoms are incorporated into gem diamond *** techniques are very important and will be widely applied.

关键词：宝石级金刚石高温高压硼原子添加剂金刚石单晶合成类型金刚石晶体

Effects of additive NaN_3 on the HPHT synthesis of large single crystal diamond grown by TGM

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Science China(Physics,Mechanics & Astronomy) 2010年第10期53卷 1831-1835页

作者： HUANG GuoFeng JIA XiaoPeng li shangsheng HU MeiHua li Yong ZHAO Ming YAN BingMin MA HongAn National Laboratory of Superhard Materials Jilin UniversityChangchun 130012China Henan Polytechnic University Jiaozuo 454000China

In this paper,large single crystal diamond with perfect shape and high nitrogen concentration approximately 1671-1742 ppm was successfully synthesized by temperature gradient method (TGM) under high pressure and high temperature (HPHT).The HPHT synthesis conditions were about 5.5 GPa and 1500-1550 *** azide (NaN3) with different amount was added as the source of nitrogen into the synthesis system of high pure graphite and kovar *** effects of additive NaN3 on crystal growth habit were investigated in *** crystal morphology,nitrogen concentration and existing form in synthetic diamond were characterized by means of scanning electron microscope (SEM) and infrared (IR) absorption spectra,*** results show that with an increase of the content of NaN3 added in the synthesis system,the region of synthesis temperature for high-quality diamond becomes narrow,and crystal growth rate is restricted,whereas the nitrogen concentration in synthetic diamond *** exists in diamond mainly in dispersed form (C-centers) and partially aggregated form (A-centers).The defects occur more frequently on crystal surface when excessive NaN3 is added in the synthesis system.

关键词： HPHT high nitrogen concentration TGM large single crystal diamond

Effects of carbon diffusing field in alloy solvent on the growth of tower-shape diamond single crystal

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Chinese Science Bulletin 2010年第1期55卷 7-10页

作者： XIAO HongYu MA HongAn TIAN Yu li Rui li shangsheng MA liQiu li Yong JIA XiaoPeng State Key Laboratory of Superhard Materials Jilin University Changchun 130012 China School of Materials Science and Engineering Henan Polytechnic University Jiaozuo 454000 China School of Materials Science and Engineering Changchun University of Science and Technology Changchun 130012 China

High-quality type-Ib tower-shape diamond single crystals were synthesized in cubic anvil high pressure apparatus (SPD-6×1200) at 5.4 GPa and 1250-1450°C. The (100) face of seed crystal was used as the growth face, and FeNiMnCo alloy was used as the solvent/catalyst. Two kinds of carbon diffusing fields (type-B and type-G) were simulated by finite element method (FEM). Using the two kinds of carbon diffusing fields, many diamond single crystals were synthesized. The effects of carbon diffusing fields on the crystal quality and β value (the ratio of height to diameter of diamond crystal) were studied. The results show that using type-B diffusing field, considerable inclusions appeared in tower-shape diamond crystals with high β values; however, using type- G diffusing field, inclusions were reduced markedly in high β values tower-shape diamond crystals, and the crystal, up to 0.6 carat in weight and 5.3 mm in size, was synthesized. Experimental phenomena were explained well with the help of the FEM.

关键词：金刚石单晶碳合金弥散效应塔型溶剂增长型金刚石晶体单晶合成

Dependence of nitrogen concentration in type Ib diamonds on synthesis temperature

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Chinese Science Bulletin 2009年第9期54卷 1459-1462页

作者： TIAN Yu JIA XiaoPeng ZANG ChuanYi li shangsheng XIAO HongYu ZHANG YaFei HUANG GuoFeng li Rui HAN QiGang MA liQiu li Yong CHEN XiaoZhou ZHANG Chong MA HongAn State Key Laboratory of Superhard Materials Jilin University Changchun 130012 China School of Materials Science and Engineering Henan Polytechnic University Jiazuo 454000 China School of Materials Science and Engineering Changchun University of Science and Technology Changchun 130012 China

Type Ib diamonds were grown by the temperature gradient method (TGM) at 5.5 GPa and 1500-1560 K in a china-type cubic anvil high pressure apparatus using Ni70Mn25Co5 alloy as solvent/catalyst. The concentration of nitrogen (CN) in type Ib diamonds synthesized at different synthesis temperatures was measured by a Fourier transform infrared (FTIR) spectrometer. The dependence of CN in diamond on synthesis temperature was studied. For the type Ib diamonds synthesized using Ni70Mn25Co5 as catalyst, its CN decreases along with the increase of synthesis temperature.

关键词：合成温度合成钻石氮浓度 Ib 依赖型傅里叶变换红外光谱温度梯度法合成金刚石

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重审手语的语言资格

中国特殊教育 2000年第4期 6-7+34+43页

作者：李尚生泉州师范学院!福建 362000

重新审视手语的语言资格不仅有利于手语的发展 ,也关系到聋校语言教育的发展方向。本文认为 ,手语在本质上已具备语言的基本特征 ,但在一定程度上和语言还有差距 ,手语是一种发展中的准语言 ,因此 ,既不能武断地剥夺手语的语言资格 ,也... 详细信息

重新审视手语的语言资格不仅有利于手语的发展 ,也关系到聋校语言教育的发展方向。本文认为 ,手语在本质上已具备语言的基本特征 ,但在一定程度上和语言还有差距 ,手语是一种发展中的准语言 ,因此 ,既不能武断地剥夺手语的语言资格 ,也不能盲目地抬高手语的语言地位。

关键词：手语语言资格

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P型和N型金刚石薄膜研究进展

材料导报 2016年第9期30卷 36-40页

作者：龚春生李尚升张贺河南理工大学材料科学与工程学院焦作454000

金刚石薄膜有着高的热导率,高的介质击穿场强,高的载流子迁移率以及宽的禁带等优点,是非常理想的功能材料。掺杂使金刚石薄膜具有独特的电学和热学性能,使其在半导体领域具有广阔的应用前景,近年来成为国内外研究的热点之一。综述了金... 详细信息

金刚石薄膜有着高的热导率,高的介质击穿场强,高的载流子迁移率以及宽的禁带等优点,是非常理想的功能材料。掺杂使金刚石薄膜具有独特的电学和热学性能,使其在半导体领域具有广阔的应用前景,近年来成为国内外研究的热点之一。综述了金刚石薄膜P型掺杂和N型掺杂的研究现状,对金刚石薄膜N型掺杂研究中存在的问题进行了分析和探索,并对N型金刚石的前景进行了展望。

关键词：金刚石薄膜 P型 N型

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基于电容器分组投切的电网谐波阻抗特性研究

高电压技术 2016年第10期42卷 3354-3360页

作者：李尚盛吴楠查晓明武汉大学电气工程学院武汉430072

投切电容器是计算电网谐波阻抗特性的常用操作方法,充分利用分组投切电容器的各组数据,可以更准确地计算电网谐波阻抗特性。为此,采用Prony算法滤除电压、电流响应中的稳态分量,得到其暂态分量。对电压、电流暂态分量进行离散Fourier变... 详细信息

投切电容器是计算电网谐波阻抗特性的常用操作方法,充分利用分组投切电容器的各组数据,可以更准确地计算电网谐波阻抗特性。为此,采用Prony算法滤除电压、电流响应中的稳态分量,得到其暂态分量。对电压、电流暂态分量进行离散Fourier变换,得到投切各组电容器时的电网谐波阻抗特性。各组电网谐波阻抗特性按照暂态时域能量大小进行权重分配,再利用3次样条插值对各离散频率处的阻抗进行拟合,构成最终的电网谐波阻抗特性。仿真结果表明,对于基于分组投切电容器的各组数据、采用时域能量权重系数法计算得到的电网谐波阻抗特性,其阻抗幅值和相位的绝对误差仅为考虑单组电容器投切时的25%,验证了所提方法的可行性。

关键词：谐波阻抗特性电能质量电容器组投切能量权重阻抗测量 Prony算法