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Textures and melt-crystal-gas interactions in granites 被引量:4
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作者 Jean-Louis Vigneresse 《Geoscience Frontiers》 SCIE CAS CSCD 2015年第5期635-663,共29页
Felsic intrusions present ubiquitous structures.They result from the differential interactions between the magma components(crystal,melt,gas phase) while it flows or when the flow is perturbed by a new magma injection... Felsic intrusions present ubiquitous structures.They result from the differential interactions between the magma components(crystal,melt,gas phase) while it flows or when the flow is perturbed by a new magma injection.The most obvious structure consists in fabrics caused by the interactions of rotating grains in a flowing viscous melt.New magma inputs through dikes affect the buk massif flow,considered as global within each mineral facies.A review of the deformation and flow types developing in a magma chamber identifis the patterns that could be expected.It determines their controlling parameters and summarizes the tools for their quantification.Similarly,a brief review of the theology of a complex multiphase magma identifies and suggests interactions between the different components.The specific responses each component presents lead to instability development.In particular,the change in vorticity orientation,associated with the switch between monoclinic to triclinic flow is a cause of many instabilities.Those are preferentially local.Illustrations include fabric development,shear zones and flow banding.They depend of the underlying rheology of interacting magmas.Dikes,enclaves,schlieren and ladder dikes result from the interactions between the magma components and changing boundary conditions.Orbicules,pegmatites,unidirectional solidification textures and miarolitic cavities result from the interaction of the melt with a gaseous phase.The illustrations examine what is relevant to the bulk flow,local structures or boundary conditions.In each case a field observation illustrates the instability.The discussion reformulates instability observations,suggesting new trails for ther description and interpretation in terms of local departure to a bulk flow.A brief look at larger structures and at their evolution tries to relate these instabilities on a broader scale.The helical structures of the Ricany pluton,Czech Republic and by the multiple granitic intrusions of Dolbel,Niger illustrate such events. 展开更多
关键词 Granitic magma INSTABILITIES triclinic flow Struct
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Structural, Thermal and Optical Studies of Oxypeucedanin Hydrate Monoacetate Micro-Crystals from <i>Prangos pabularia</i> 被引量:1
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作者 Javid Ahmad Banday Feroz Ahmad Mir +3 位作者 Saleem Farooq Mushtaq Ahmad Qurishi Surinder Koul Tej Kishen Razdan 《American Journal of Analytical Chemistry》 2012年第3期204-209,共6页
Oxypeucedanin hydrate monoacetate (Mol. Formula = C18H18O7) micro-crystals were obtained by acetylation of oxy-peucedanin hydrate, a furanocoumarin, isolated from the roots of Prangos pabularia. The composition relate... Oxypeucedanin hydrate monoacetate (Mol. Formula = C18H18O7) micro-crystals were obtained by acetylation of oxy-peucedanin hydrate, a furanocoumarin, isolated from the roots of Prangos pabularia. The composition related structural, thermal and optical properties were investigated. All the crystals were found to have triclinic structure. From thermal studies of these crystals, stability, melting point and other relevant informations were obtained. Their blue emission, less absorption in entire visible range and band gap predicts these crystals as good candidate for modern optoelectronic devices. 展开更多
关键词 Prangos pabularia Oxypeucedanin HYDRATE Monoaceate FURANOCOUMARIN triclinic Non-Linear Optical
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Dichroic Electro-Optical Behavior of Rhenium Sulfide Layered Crystal 被引量:1
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作者 Ching-Hwa Ho 《Crystal Structure Theory and Applications》 2013年第2期65-69,共5页
Dichroic behaviors of layered ReS2 have been characterized using angular dependent polarizedabsorption and resistivity measurements in the van der Waal plane. The angular dependent optical and electrical measurements ... Dichroic behaviors of layered ReS2 have been characterized using angular dependent polarizedabsorption and resistivity measurements in the van der Waal plane. The angular dependent optical and electrical measurements are carried out with angles ranging from θ= 0°(E || b) to θ= 90°(E ^b) with respect to the layer crystal’s b-axis. The angular de pendence of polarized energy gaps of ReS2 shows a sinusoidal variation of energies from ~1.341 eV (E ||b to ~1.391 eV (E ^ b). The experimental evidence of polarized energy gap leaves ReS2 apotential usage for fabrication of a polarized optical switch suitable for polarized optical communication in nearinfrared (NIR) region. Angular dependence of resistivities of ReS2 in?the vander Waal plane has also been evaluated. The relationship of inplane resistivities shows a sinusoidallike variation from θ= 0°(E ||b) to 90°(E ^ b) and repeated periodically to 360°. The experimental results of optical and electrical measurements indicated that ReS2 is not only an opticaldichroic layer but also an electricaldichroism material presented in the layer plane. 展开更多
关键词 triclinic CRYSTALS Optical Materials Polarization-Sensitive Devices
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The structure and dielectric properties of ionic compounds with flexible ammonium moiety 被引量:1
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作者 Hui-Ting Wang Li-Hui Kong +3 位作者 Ping-Ping Shi Qiang Li Qiong Ye Da-Wei Fu 《Chinese Chemical Letters》 SCIE CAS CSCD 2015年第3期382-386,共5页
The 3-morpholin-4-yl-propyl-ammine tetrafluoroborate(MPA^+)(BF4^-)(1) and the 3-morpholin-4-ylpropyl-ammine perchlorate(MPA^+)(ClO4^-)(2) were synthesized and separated as colorless block crystal.The(M... The 3-morpholin-4-yl-propyl-ammine tetrafluoroborate(MPA^+)(BF4^-)(1) and the 3-morpholin-4-ylpropyl-ammine perchlorate(MPA^+)(ClO4^-)(2) were synthesized and separated as colorless block crystal.The(MPA^+)(BF4^-) undergoes a reversible phase transition at ca.347.3 K with a hysteresis of16.1 K.Dielectric measurement also can confirm the transition.The crystal structure determined at300 K(monoclinic,P21/c,a = 9.978(2)A,b = 7.5206(15)A,c = 15.058(3)A,b = 96.99(3)8,v = 1121.6(4)A^3,z = 4) and 373 K(triclinic,P-1,a = 10.021(7)A,b = 7.662(3)A,c = 7.920(4)A,a = 95.012(14)8,b = 101.67(4)8,g = 91.48(3)8,v = 592.7(6)A^3,z = 2) reveal that this compound has two phase.The most distinct is the BF4^- anion is disorder at 373 K,which is probably the driving force of the phase transition.DSC measurement,dielectric measurement and the crystal structure of the compound 2 did not change at 300 K and 100 K. 展开更多
关键词 moiety ionic dielectric triclinic reversible monoclinic propyl ammonium anion cyclohexane
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Synthesis and Crystal Structure of 2-(4-Chlorophenyl)-1,4,5-triphenyl-1H-imidazole
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作者 Ali Mohammad Amani Kazem Barati 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第4期574-576,共3页
The compound 2-(4-chlorophenyl)-1,4,5-triphenyl-1H-imidazole(1,C27H19ClN2) has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction.The crystal of 1 belongs to the triclini... The compound 2-(4-chlorophenyl)-1,4,5-triphenyl-1H-imidazole(1,C27H19ClN2) has been synthesized and its crystal structure was determined by single-crystal X-ray diffraction.The crystal of 1 belongs to the triclinic system,space group P with a = 10.3350(19),b = 10.238(2),c = 11.201(2) ,α = 85.957(16),β = 83.148(15),γ = 66.467(15)°,V = 1078.5(4) 3,Mr = 406.89,Z = 2,F(000) = 422,Dc = 1.257 g/cm3,μ = 0.193 mm-1,T = 298(2) K,S = 1.092,R = 0.0702 and wR = 0.1258.The imidazole ring system is planar and makes a dihedral angle of 40.3° with the chlorobenzene ring. 展开更多
关键词 crystal structure IMIDAZOLE triclinic system
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Hydrazine processed Cu2SnS3 thin film and their application for photovoltaic devices
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作者 Jun HAN Ying ZHOU +7 位作者 Yang Tian Ziheng HUANG Xiaohua WANG Jie ZHONG Zhe XIA Bo YANG Haisheng SONG Jiang TANG 《Frontiers of Optoelectronics》 CSCD 2014年第1期37-45,共9页
Copper tin sulfide (Cu2SnS3) was a potential earth abundant absorber material for photovoltaic device application. In this contribution, triclinic Cu2SnS3 film with phase pure composition and large grain size was fa... Copper tin sulfide (Cu2SnS3) was a potential earth abundant absorber material for photovoltaic device application. In this contribution, triclinic Cu2SnS3 film with phase pure composition and large grain size was fabricated from a hydrazine solution process using Cu, Sn and S as the precursors. Absorption measurement revealed this Cu2SnS3 film had a direct optical band gap of 0.88 eV, and Hall effect measurement indicated the film was p-type with hole mobility of 0.86 cmE/Vs. Finally Mo/Cu2SnS3/ CdS/ZnO/AZO/Au was produced and the best device efficiency achieved was 0.78%. Also, this device showed improved device performance during ambient storage. This study laid some foundation for the further improve- ment of Cu2SnS3 solar cell. 展开更多
关键词 copper tin sulfide (Cu2SnN3) solar cell hydrazine solution process triclinic
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Reflection for three-dimensional plane waves in triclinic crystalline medium
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作者 Amares Chattopadhyay 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2007年第10期1309-1318,共10页
The propagation of three-dimensional plane waves at a traction free boundary of a half-space composed of triclinic crystalline material is discussed. A method has been developed to find the analytical expressions of a... The propagation of three-dimensional plane waves at a traction free boundary of a half-space composed of triclinic crystalline material is discussed. A method has been developed to find the analytical expressions of all the three phase velocities of quasi-P (qP), quasi-SV (qSV) and quasi-SH (qSH) in three dimensions. Closed form expressions in three dimensions for the amplitude ratios of reflection coefficients of qP, qSV and qSH waves in a triclinic medium are obtained. These expressions are used for numerically studying the variation of the reflection coetticients with the angle of incidence. The graphs are drawn for different polar angle and azimuth. Numerical results presented indicate that the anisotropy affect the reflection coetticients significantly in the three dimensional case compared to the two-dimensional case. 展开更多
关键词 THREE-DIMENSIONAL polar angle AZIMUTH REFLECTION triclinic medium quasi-P quasi-SV quasi-SH waves
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Synthesis and Molecular Structure of 5-Amino-7-(benzo[d][1,3]dioxol-5-yl)-2,3-dihydro-1H-indene-4,6-dicarbonitrile
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作者 刘雷芳 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第5期649-652,共4页
The title compound, C18H13N3O2, has been synthesized for the first time by the multicomponent reaction of cyclopentanone, malononitrile and benzo[d][1,3]dioxole-5-carbalde-hyde in the presence of triethylamine. The st... The title compound, C18H13N3O2, has been synthesized for the first time by the multicomponent reaction of cyclopentanone, malononitrile and benzo[d][1,3]dioxole-5-carbalde-hyde in the presence of triethylamine. The structure has been determined by NMR, MS and single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space group P with a = 10.476(5), b = 10.973(5), c = 13.825(5), α = 87.244(5), β = 73.296(5), γ = 82.097(5)°, C18H13N3O2, Mr = 303.31, V = 1507.6(11) 3, Z = 4, Dc = 1.336 g/cm3, F(000) = 632, μ = 0.090 mm-1, R = 0.0431 and wR = 0.1051. There exist intermolecular N-H…N hydrogen bonds in the title compound. 展开更多
关键词 crystal structure triclinic system multicomponent reaction
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TABLES OF SECOND-RANK ESTIMATED FORMULAS OF STRUCTURE SEMI-INVARIANT IN TRICLINIC AND MONOCLINIC SPACE GROUPS
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作者 刘永盛 《Chinese Science Bulletin》 SCIE EI CAS 1988年第21期1788-1793,共6页
In this report the second-rank estimated formulas of one phase structure semiinvariants of 15 space groups in triclinic and monoclinic crystal systems are given using the algebraic derivative method. These formulas ma... In this report the second-rank estimated formulas of one phase structure semiinvariants of 15 space groups in triclinic and monoclinic crystal systems are given using the algebraic derivative method. These formulas may be used to determine the phases of structure factors in direct phase determination. The mathematical esti- 展开更多
关键词 triclinic and MONOCLINIC space GROUPS crystal
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DETERMINATION AND REFINEMENT OF THE CRYSTAL STRUCTURE OF CHAIDAMUITE
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作者 李万茂 王奇光 《Science China Chemistry》 SCIE EI CAS 1990年第5期623-630,共8页
Chaidamuite (ZnFe(SO_4)_2(OH). 4H_2O), which is a new sulphate mineral, belongs to the triclinic system, space group P1, with the cell parameters corrected by the least-squares method: a=7.309(2), b=7.202(2), c=9.691(... Chaidamuite (ZnFe(SO_4)_2(OH). 4H_2O), which is a new sulphate mineral, belongs to the triclinic system, space group P1, with the cell parameters corrected by the least-squares method: a=7.309(2), b=7.202(2), c=9.691(3), α=89.64(3), β=105.89(3), γ=91.11(2)°, Z=2. The crystal structure has been determined by the Patterson method and Fourier syntheses and refined by the full-matrix least-squares method to an R factor of 0.032, using 2833 independent reflections. In the structure, a zigzag chain consists of [Fe(1)O_5(OH)] and [Fe(2)O_5(OH)] octahedra sharing the OH corners, and an octahedral-tetrahedral chain running parallel to the b axis consists of the zigzag chain of Fe octahedra and (SO_4) tetrahedra sharing four pairs of octahedral corners on either side of the zigzag chains. These chains are cross-linked by the isolated [Zn(1)O_2(H_2O)_4] and [Zn(2)O_2(H_2O)_4] octahedra into corrugated sheets parallel to the (100) plane. Adjacent sheets are hydrogenbonded through water molecules. 展开更多
关键词 Chaidamuite CRYSTAL STRUCTURE triclinic P1.
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Reflection of three-dimensional plane waves at the free surface of a rotating triclinic half-space under the context of generalized thermoelasticity 被引量:1
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作者 P.SINGH A.K.SINGH A.CHATTOPADHYAY 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2021年第9期1363-1378,共16页
The reflection of three-dimensional(3D) plane waves in a highly anisotropic(triclinic) medium under the context of generalized thermoelasticity is studied. The thermoelastic nature of the 3D plane waves in an anisotro... The reflection of three-dimensional(3D) plane waves in a highly anisotropic(triclinic) medium under the context of generalized thermoelasticity is studied. The thermoelastic nature of the 3D plane waves in an anisotropic medium is investigated in the perspective of the three-phase-lag(TPL), dual-phase-lag(DPL), Green-Naghdi-III(GNIII), Lord-Shulman(LS), and classical coupled(CL) theories. The reflection coefficients and energy ratios for all the reflected waves are obtained in a mathematical form. The rotational effects on the reflection characteristics of the 3D waves are discussed under the context of generalized thermoelasticity. Comparative analyses for the reflection coefficients of the waves among these generalized thermoelastic theories are performed. The energy ratios for each of the reflected waves establish the energy conservation law in the reflection phenomena of the plane waves. The highly anisotropic materials along with the rotation may have a significant role in the phenomenon of the reflection behavior of the 3D waves. Numerical computations are performed for the graphical representation of the study. 展开更多
关键词 REFLECTION energy ratio triclinic THERMOELASTICITY ROTATION three-dimensional(3D)wave
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水合(1,10-邻二氮菲)三苯基氯化锡的合成与晶体结构 被引量:1
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作者 付彩霞 高宗华 +1 位作者 马春林 张军红 《合成化学》 CAS CSCD 2005年第1期55-57,共3页
合成了水合(1,10邻二氮菲)三苯基氯化锡配合物,其结构经X射线单晶衍射,1HNMR,IR和元素分析表征,其晶体结构属于三斜晶系,P墿空间群a=1.2064(4)nm,b=1.2075(4)nm,c=1.8603(6)nm,α=99.562(6)°,β=99.567(5)°,γ=92.702(5)°... 合成了水合(1,10邻二氮菲)三苯基氯化锡配合物,其结构经X射线单晶衍射,1HNMR,IR和元素分析表征,其晶体结构属于三斜晶系,P墿空间群a=1.2064(4)nm,b=1.2075(4)nm,c=1.8603(6)nm,α=99.562(6)°,β=99.567(5)°,γ=92.702(5)°,V=2.6272(15)nm3,Z=4,F(000)=1176,R1=0.0593,wR2=0.1084。配合物由1,10邻二氮菲的两个氮原子通过NHO氢键与三苯基氯化锡连接组成。锡原子为五配位的三角双锥构型。 展开更多
关键词 配合物 三斜晶系 合成 晶体结构
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STUDY ON β-FORM POLYPROPYLENE
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作者 史观一 张景云 《Chinese Science Bulletin》 SCIE EI CAS 1982年第3期290-294,共5页
Isotactic polypropylene is capable of crystallizing in several forms. The α or monoclinie form is the most stable and prevalent form. A γ or triclinic modification exists, which is generally associated with high pre... Isotactic polypropylene is capable of crystallizing in several forms. The α or monoclinie form is the most stable and prevalent form. A γ or triclinic modification exists, which is generally associated with high pressure crystallization. A third crystalline modification, the β or hexagonal form, is occasionally found in commercial polypropylene, usually at low levels. Work by H. J. Leugering has shown that small amounts of a quinacridone colorant, permanent red E3B, preferentially nucleated 展开更多
关键词 HEXAGONAL crystalline preferentially POLYPROPYLENE permanent OCCASIONALLY capable STUDY ON heating triclinic
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CRYSTAL AND MOLECULAR STRUCTURE OF A CRYPTATE COMPLEX OF EUROPIUM: C_(18)H_(36)O_6N_2Eu_2(NO_3)_6·H_2O
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作者 杨光第 刘世昌 金钟声 《Chinese Science Bulletin》 SCIE EI CAS 1987年第3期214-215,共2页
For their special coordination function, cryptate compounds will play an important part in such fields as bionics, biophysics, medicine and pesticide. But, very few research results have been reported so far on lantha... For their special coordination function, cryptate compounds will play an important part in such fields as bionics, biophysics, medicine and pesticide. But, very few research results have been reported so far on lanthanide cryptate compounds, of which only 3 structures have been determined. 展开更多
关键词 pesticide LANTHANIDE H2O NO3 O6N2Eu2 slightly coordinated BIDENTATE reacting triclinic
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Effect of Misfit Strain on Pyroelectric Properties of (111) Oriented Pb(Zr_(1-x)Ti_x)O_3 Thin Films
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作者 Jian-Hua Qiu Zhi-Hui Chen +2 位作者 Xiu-Qin Wang Ning-Yi Yuan Jian-Ning Ding 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第10期453-458,共6页
Based on the Landau-Dovenshire theory,the thermodynamic potential of(111) oriented films is constructed to investigate the pyroelectric properties of Pb(Zr_(1-x)Ti_x)O_3 thin films.Due to the presence of nonlinear cou... Based on the Landau-Dovenshire theory,the thermodynamic potential of(111) oriented films is constructed to investigate the pyroelectric properties of Pb(Zr_(1-x)Ti_x)O_3 thin films.Due to the presence of nonlinear coupling terms resulted from the(111) epitaxy with substrates,the effects of misfit strain and electric field on the phase transitions at room temperature are more complex than that of(001) and(110) oriented films.Pb(Zr_(1-x)Ti_x)O_3 thin films with the Ti composition around the morphotropic phase boundary(MPB) have the giant dielectric and pyroelectric properties.Moreover,Pb(Zr_(1-x)Ti_x)O_3 thin films grown on the tensile substrates which induce the triclinic γ phase have the larger dielectric and pyroelectric properties than that on the compressive substrates.Therefore,the physical properties of(111)oriented Pb(Zr_(1-x)Ti_x)O_3 thin films can be adjusted by choosing the suitable substrates. 展开更多
关键词 FERROELECTRICS dielectric property pyroelectric effect
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CRYSTAL STRUCTURE OF GOSSYPOL ACETIC ACID
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作者 徐常富 贺存恒 +1 位作者 鲍光宏 穆善田 《Chinese Science Bulletin》 SCIE EI CAS 1981年第10期959-960,共2页
Gossypol acetic acid (C30H34O8-CH3COOH) is a contraceptive drug for man, which is being investigated clinically and pharmacologically at present in our country. The crystal structure of gossypol acetic acid has been d... Gossypol acetic acid (C30H34O8-CH3COOH) is a contraceptive drug for man, which is being investigated clinically and pharmacologically at present in our country. The crystal structure of gossypol acetic acid has been determined by single crystal X-ray analysis. Single crystal of gossypol acetic acid was obtained from acetone-acetic acid solution. According to X-ray diffraction photographs, the crystal is found to be triclinic with crystallographic parameters α=14.278, b=6.924, c=14.406; α=91.90°, β=92.34°, γ=98.71°and Z=2. The calculated density D=1.350 gcm-3, M. W.=578. 展开更多
关键词 acetic triclinic ACID ACETONE clinically determ TANGENT MERIT
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Hydrothermal Synthesis and Crystal Structure of [(CH_3CH_2)_4N]_4[(La_(12)(OH)_(12)MoO_(29) )], A Novel Cluster Compound with a MoO_5 Hexahedron Center Surrounded by La-O Octahedron
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作者 HUChang-wen HUANGWei-tong +6 位作者 ZHANGHong WANGXiu-li LIYang-guang DUANGLi-ying LANYang WANGLi WANGEn-bo 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第2期132-134,共3页
A novel compound [(CH 3CH 2) 4N] 4[(La 12 (OH) 12 MoO 29 )] was synthesized by hydrothermal reaction. The single crystal X ray diffraction shows that the compound crystallized in the monoclinic space group C2/c ; a =2... A novel compound [(CH 3CH 2) 4N] 4[(La 12 (OH) 12 MoO 29 )] was synthesized by hydrothermal reaction. The single crystal X ray diffraction shows that the compound crystallized in the monoclinic space group C2/c ; a =2 5729(4) nm, b =1 4318(1) nm, c =2 1217(4) nm, β =111 56(1)°, V =6 8235(7) nm 3, Z =4, R =0 0751. The basic building blocks of the crystal structure included one MoO 5 hexahedron and twelve LaO 6 octahedra which shared a common edge to form a [(La 12 (OH) 12 MoO 29 )] 4- unit. These units were held together by the [(CH 3CH 2) 4N] + ions. 展开更多
关键词 Hydrothermal synthesis Layer Lanthanum triclinic system
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模拟表生环境水钠锰矿亚结构转化及钙锰矿的形成 被引量:5
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作者 赵怀燕 龚爱蓉 +4 位作者 殷辉 刘凡 谭文峰 邱国红 冯雄汉 《地球科学(中国地质大学学报)》 EI CAS CSCD 北大核心 2014年第2期227-239,共13页
水钠锰矿是土壤与沉积物中最为常见的氧化锰矿物,依据其MnO6层对称特点分为六方和三斜两种亚结构类型.六方水钠锰矿在表生环境中可通过Mn2+的化学或生物氧化形成,而环境中三斜水钠锰矿的形成及进一步转化为钙锰矿的途径尚不清楚.以两种... 水钠锰矿是土壤与沉积物中最为常见的氧化锰矿物,依据其MnO6层对称特点分为六方和三斜两种亚结构类型.六方水钠锰矿在表生环境中可通过Mn2+的化学或生物氧化形成,而环境中三斜水钠锰矿的形成及进一步转化为钙锰矿的途径尚不清楚.以两种六方水钠锰矿(酸性水钠锰矿和水羟锰矿)为前驱物,采用X射线吸收光谱(EXAFS)、X射线衍射(XRD)、电镜(FESEM/TEM)及化学组成分析等技术方法模拟表生环境研究了水钠锰矿从六方向三斜的亚结构转化及生成钙锰矿的化学条件和矿物学机制.结果表明,适当Mn(Ⅱ)浓度和弱碱性条件(pH≥8)可使六方水钠锰矿逐渐转化为三斜水钠锰矿,继而经Mg2+交换、常压回流得到了长纤维状的钙锰矿,其晶体生长以溶解-结晶为主.Mn(Ⅱ)与六方水钠锰矿MnO6八面体层内的Mn(Ⅳ)反应生成Mn(Ⅲ)并填充层内空位,使水钠锰矿对称型由六方向三斜转变.与酸性水钠锰矿相比,水羟锰矿结晶弱、层状堆积混乱度高,与Mn(Ⅱ)反应迅速,层结构向三斜水钠锰矿转化快.pH升高,促进六方水钠锰矿对Mn(Ⅱ)的吸附和Mn(Ⅱ)与Mn(Ⅳ)间的反应,六方水钠锰矿转化为三斜水钠锰矿的速率加快."六方水钠锰矿→三斜水钠锰矿"可能是环境中三斜水钠锰矿的重要来源,及进一步形成钙锰矿的重要化学生成机制. 展开更多
关键词 水钠锰矿 六方水钠锰矿 三斜水钠锰矿 钙锰矿 转化 环境地质
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剪切带运动学:重点评述三斜模式和区分韧性滑动擦痕与拉伸线理的重要性 被引量:4
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作者 林寿发 姜大志 +3 位作者 Paul F. Williams Shoufa LIN Dazhi JIANG Paul F WILLIAMS 《地质通报》 CAS CSCD 北大核心 2007年第9期1139-1153,共15页
详细评述了剪切带运动学和内部几何学研究的新进展。剪切带内的递进变形一般为三斜对称,单斜剪切带(包括简单剪切带)是特例情形。理论模拟表明,如同许多天然剪切带中所见到的,在三斜剪切带中,拉伸线理的方位可从近水平到平行于倾向连续... 详细评述了剪切带运动学和内部几何学研究的新进展。剪切带内的递进变形一般为三斜对称,单斜剪切带(包括简单剪切带)是特例情形。理论模拟表明,如同许多天然剪切带中所见到的,在三斜剪切带中,拉伸线理的方位可从近水平到平行于倾向连续变化。过去一般将拉伸线理的方向当作剪切运动方向的做法是以简单剪切模式为基础的,不适合于一般剪切带。在三斜剪切带中,拉伸线理和剪切方向之间不存在简单关系。然而,C面上的韧性滑动擦痕平行于剪切方向发育,是剪切方向的可靠标志。因此,在剪切带运动学解释中区分韧性滑动擦痕与拉伸线理非常重要。 展开更多
关键词 剪切带 运动学 三斜模式 剪切方向 拉伸线理 韧性滑动擦痕
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三斜相GdBO_3:Eu的溶胶 凝胶法制备及其格位选择激发下的光谱(英文) 被引量:2
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作者 张巍巍 谢平波 +3 位作者 张慰萍 张运生 楼立人 夏上达 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2001年第3期323-329,共7页
用溶胶 凝胶法合成了具有三斜结构的低温相GdBO3,并与用常规的固相反应制备的类球方解石结构的样品作了比较。在高于 1 0 0 0℃时发生了三斜相向常规相的相变。三斜相GdBO3:Eu的荧光光谱表明阳离子在基质晶格中占据了两种格位 ,用A和B... 用溶胶 凝胶法合成了具有三斜结构的低温相GdBO3,并与用常规的固相反应制备的类球方解石结构的样品作了比较。在高于 1 0 0 0℃时发生了三斜相向常规相的相变。三斜相GdBO3:Eu的荧光光谱表明阳离子在基质晶格中占据了两种格位 ,用A和B来分别标明。选择激发A、B格位上Eu3+ ,结果揭示了GdBO3结构上的变化和Eu3+ 之间的能量传递过程。在较高的Eu3+ 掺杂浓度时 ,两个格位均有较强的发光 ;在低温和低浓度条件下 ,得到了可分辨的相应于不同格位的发光 ,并观察到了两个格位间不同几率的能量相互传递。 展开更多
关键词 溶胶-凝胶 选择激发 能量传递 相变 制备 光谱
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