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为确定萝北石墨尾矿资源的合理回收工艺,通过X-射线粉晶衍射、碳元素分析、扫描电镜和电子偏光显微镜等仪器和方法对萝北石墨尾矿进行了详细的工艺矿物学研究.结果表明:该石墨尾矿主要由石英、长石(钾长石和钙长石)、绢云母、方解石、赤铁矿、透闪石、绿泥石和残留的少量石墨(2.5;)组成.石英和长石为主要物相,其总量超过尾矿的三分之二.绢云母占总量的7;左右,大多呈细小片状或伸长薄片状,延伸方向上长度为0.03 ~0.5mm,大部分集中在0.15 ~0.4 mm,大多结合在石英和长石等较大颗粒的表面或边缘.石墨多呈细小片状和不规则的粒状、条状,延伸方向上长度为0.02~0.5 mm,集中在0.1~0.25 mm范围内.较大片层独立分布,小片层常常包覆于石英或长石的表面.绢云母和石墨在200目下明显富集,使其从尾矿中被回收利用成为可能. 相似文献
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以乙酸锌、正丁胺及水杨醛为原料在甲醇介质中反应,合成得到了席夫碱配合物N-亚水杨基正丁胺锌[Zn(CH3CH2 CH2CH2N=CHC6H4O)2],用元素分析、红外光谱、核磁共振氢谱和热重分析进行了谱学表征,培养了该配合物的单晶,并通过单晶X射线衍射测得其晶体结构为四方晶系, 空间点群为P-4,a=1.4380(2)nm,b=1.4380(2)nm,c=0.53803(18)nm,α=β =γ=90°,V=1.1126(4)nm3 ;Dc =1.247 g/cm3;Z=2;F(000) = 400;μ =1.12mm-1.锌离子位于变形四面体的中心,分别与两个席夫碱N原子和两个酚氧负离子形成配合物. 相似文献
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利用显微Raman光谱技术,对比研究了CdZnTe晶体无位错区和位锘密集区的Raman光谱.研究发现,CdZnTe晶体无位错区的Raman光谱出现了与Te有关的A1模(119 cm-1)、类CdTe的TO1模(138 cm-1)和类ZnTe 的TO2模(179 cm-1);CdZnTe晶体位错密集区的Raman光谱中仅出现了与Te有关的A1模和类CdTe的TO1模,CdZnTe晶体类ZnTe的TO2模消失.对CdZnTe试样位错密集区进行变温光致发光谱测试,结果表明,束缚在中性施主上的激子的离解为电子空穴对,电子空穴的非辐射复合过程吸收了类ZnTe的TO2模声子能量,造成Raman 光谱中类ZnTe的TO2模缺失. 相似文献
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以氧氯化锆生产排放的酸性锆硅渣为主要原料,经脱酸除杂得到硅凝胶,按nCaO∶nSiO2=1∶1、W∶S(水/固质量比)=30∶1与消石灰加水混合均匀,采用动态水热法合成硬硅钙石。利用XRD、FT-IR、SEM等方法,研究了硬硅钙石的合成条件和合成机理。结果表明,锆硅渣经消石灰中和水洗可有效脱酸除杂,并可降低硅凝胶的[SiO4]4-聚合度,提高其反应活性。用此硅凝胶作硅源,在200℃下反应6 h即可合成长径比为40~60的纯相纤维状硬硅钙石。反应过程中,硬硅钙石系由CSH凝胶直接转化而成,未经历托贝莫来石相的过渡。 相似文献
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本文以硝酸镁、硝酸铝为原料,以碳酸钠和氢氧化钠为沉淀剂和pH值调节剂,采用液相沉淀法制备了纳米镁铝水滑石层状化合物(Mg-Al-LDHs),利用X射线衍射(XRD)、扫描电镜(SEM)及X射线能谱分析仪(EDS)系统比较研究了pH值、反应温度、镁铝比等条件对合成LDHs晶体微结构及晶体生长的影响,同时利用生长基元的配位体理论对其生长机理进行了初步探讨,在此基础上,以甲基橙(MO)模拟染料废水为吸附对象,考察了最佳条件下制备的LDHs培烧产物的吸附性能和吸附机理.研究结果表明:pH值、温度的增加有利于生成结构单一、结晶性、规整性较好的镁铝水滑石晶体,产物晶粒尺寸及径厚比呈增大趋向.当反应温度等于或大于80℃时,温度的升高对镁铝水滑石晶体的形态影响较小.镁铝比的改变对产物的物相影响较小,但影响产物的结晶及生长,当镁铝比为3∶1时,所得产物晶粒的规整度、均一性最好,尺寸约为70-100 nm,厚度为20 nm左右,镁铝比为1∶1时,晶粒粒径明显减小,约为30 nm左右.最佳条件下合成的纳米镁铝水滑石焙烧产物具有较好的吸附性能,随着时间的增加,吸附脱色率逐渐增加,当吸附时间达到70 min,LDO对染料的吸附逐渐达到饱和平衡,脱色率达到90;以上,吸附动力学研究表明LDHs对甲基橙的吸附过程更符合准一级动力学方程,其R2值更接近1,吸附等温线符合Iangmuir模型. 相似文献
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合成了配合物[Zn(C28H20N4O2)(CH3OH)]并对其进行了元素分析和红外光谱表征.X射线单晶结构分析表明该配合物为一单螺旋结构,Zn(Ⅱ)原子呈现扭曲的三角双锥配位构型.晶体中分子间存在的边对面和边对边的π…π作用、C-H…π作用以及O-H…O氢键作用使其形成三维网状结构.该晶体属于三斜晶系P(1-)空间群,晶胞参数分别为:α=0.9303(2)nm,b=1.0413(2)nm,c=1.4625(3)nm,α=96.340(10)°,β=103.160(10)°,γ=112.500(10)°,V=1.2434(4)nm3,Z=2dc=1.447g cm-3,T=293(2)K,μ=1.027mm-1,F(000)=560,R1=0.0463,wR2=0.0941[I>2K(I)]. 相似文献
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Amitabha Datta Nirmal Kumar Karan Samiran Mitra Volker Gramlich 《Journal of chemical crystallography》2003,33(7):579-583
The nickel(II) complex [Ni(C4H3NCH=N–(CH2)3–N=CHC4H3N)], (1) containing the symmetrical N4 tetradentate Schiff base ligand, which is the 2:1 condensation product of pyrrole-2-carboxaldehyde and 1,3-diaminopropane respectively, was prepared. Structural investigation shows that it is monomeric, having space group P21/c, a = 7.989(7), b = 17.406(14), c = 9.193(5) Å, = 90, = 100.39(6), = 90, and Z = 4. The coordination geometry around the nickel atom is slightly distorted square planar and the conformation of the six-membered ring containing the metal,azomethine nitrogens and three carbon atoms of the connecting 1,3-diaminopropane is a symmetric boat. 相似文献
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V. V. Atuchin V. G. Kesler I. A. Lisova L. D. Pokrovsky N. A. Pylneva A. M. Yurkin 《Crystal Research and Technology》2003,38(10):896-902
The electronic and structural properties of LiB3O5 (LBO) surfaces have been studied by X‐ray photoemission spectroscopy (XPS) and reflectance high‐energy electron diffraction (RHEED). The as‐grown (110) crystal face and mechanically polished (001) surfaces have been investigated comparatively. Electronic structure of LBO has been determined on as‐grown (110) crystal face previously cleaned by chemical etching with RHEED control. The correlation of valence band structure and measured binding energies with earlier reported results has been discussed. Core‐level spectroscopy reveals strong enriching of mechanically polished LBO surface with carbon, when nanodiamond powder is used as an abrasive. So high carbon level as C:B = 0.7 has been observed at the surface while the ratio Li:B:O remains according to LBO chemical composition. The association of LBO Kikuchi‐lines with strong background has been shown by RHEED analysis of the surface. Thus, the polished LBO surface constitutes a high structure quality LBO with the inclusions of some amorphous carbon compound. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Element‐specific structural analysis at the buried interface of a low electron density contrast system is important in many applied fields. The analysis of nanoscaled Si/B4C buried interfaces is demonstrated using resonant X‐ray reflectivity. This technique combines information about spatial modulations of charges provided by scattering, which is further enhanced near the resonance, with the sensitivity to electronic structure provided by spectroscopy. Si/B4C thin‐film structures are studied by varying the position of B4C in Si layers. Measured values of near‐edge optical properties are correlated with the resonant reflectivity profile to quantify the element‐specific composition. It is observed that, although Si/B4C forms a smooth interface, there are chemical changes in the sputtered B4C layer. Nondestructive quantification of the chemical changes and the spatial distribution of the constituents is reported. 相似文献
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Yannan Qian Rui Wang Lili Xing Yanling Xu Chunhui Yang Xinrong Liu 《Crystal Research and Technology》2011,46(11):1137-1142
Congruent Er3+(3 mol%):LiNbO3 crystals codoped with ZnO (X mol %, X=0, 3, 6 and 7) were grown by the Czochralski technique. The Er contents in the crystals were measured by an inductively coupled plasma atomic emission spectrometer (ICP‐AES). Under 800 nm excitation, the upconversion emission spectra reveal an enhancement of the green emission with respect to the red emission when the Zn2+ ions are introduced into Er:LiNbO3 crystal. The effect of Zn2+ ions concentration on the intensity ratio of the green to red emission has been investigated. Two cross‐relaxation processes (2H11/2 + 4I13/2 → 4I11/2 + 4F9/2 and 4F7/2 + 4I11/2 → 4F9/2 + 4F9/2) are involved in populating the 4F9/2 state, which bypass the green‐emitting states. The OH‐ absorption spectra indicate that the Zn2+ codoping leads to a decreased concentration of Er3+ cluster sites contributing to the enhancement of the green emission. The studies on UV‐vis absorption spectra show that the heavily codoped with Zn2+ results in the reformation of the Er3+ cluster sites in Er:LiNbO3. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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Resonant X‐ray reflectivity can combine the layer sensitivity of the reflectivity technique with the chemical composition sensitivity of the absorption technique. The idea is demonstrated through a depth profile study of the chemical composition of a multi‐element thin‐film system at the soft X‐ray spectral range near the boron K absorption edge. The composition profile of a multi‐element low‐contrast (<0.6%) thin film is determined from the free surface to buried interfaces within a few atomic percentages of precision and with a nanometre depth resolution. 相似文献
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本文基于密度泛函理论的平面波超软赝势方法,采用第一性原理研究了含Cd空位缺陷CdS和含S空位缺陷纤锌矿CdS的几何结构、能带结构、电子态密度及光学性质。通过计算分析可知,含Cd空位缺陷的CdS体系均为p型半导体,含S空位缺陷的CdS体系跃迁方式均由直接跃迁变为间接跃迁。Cd、S空位缺陷的CdS体系的态密度总能量降低。空位CdS体系相较于本征CdS体系的静介电常数均有提高,并随着空位浓度的增大而增大,Cd空位缺陷体系更为明显,极化能力得到显著提升。空位Cd的CdS体系相较于本征CdS体系在红外波段存在明显的吸收,空位S的CdS体系相较于本征CdS体系在可见光波段存在明显的吸收。 相似文献
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The title compound, 5-amino-4-cyano-1-[(5-methyl-1-t-butyl-4-pyrazolyl)carbonyl]-3-methylthio-1H-pyrazole 5, was synthesized by the treatment of 4 (5-methyl-1-t-butylpyrazole-4-carbohydrazide) with 2-cyano-3, 3-dimethylthio-acrylonitrile, and its crystal structure was determined by X-ray diffraction method. The crystal belongs to monoclinic, space group P21/c with unit cell parameters a = 13.566(4) Å, b = 10.833(3) Å, c = 11.202(3) Å, α = 90°, β = 98.073(5)°, γ = 90°, V = 1629.9(8) Å3, Z = 4, D
c = 1.298, M
r = 318.40, μ = 0.210 mm−1, F(000) = 672, R
1 = 0.0488 and wR
2 = 0.1250. 相似文献