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湘南桂阳六合土话的否定词 被引量:4
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作者 邓永红 《语言研究》 CSSCI 北大核心 2006年第2期81-84,共4页
桂阳六合土话的否定词主要有五个:唔[■45]、唔曾[■45 t■hi■13]、冇得[mo45 ti■42]、冇[mo45]和莫[mo45]。否定名词性成分通常用“冇得”和“冇”;否定谓词性成分用“唔”和“唔曾”;对主观意愿、某种习惯或某种状态的否定,通常用... 桂阳六合土话的否定词主要有五个:唔[■45]、唔曾[■45 t■hi■13]、冇得[mo45 ti■42]、冇[mo45]和莫[mo45]。否定名词性成分通常用“冇得”和“冇”;否定谓词性成分用“唔”和“唔曾”;对主观意愿、某种习惯或某种状态的否定,通常用“唔”;对完成体的否定,则说成“唔曾”;表禁止否定用“莫”。 展开更多
关键词 桂阳土话 否定词 湘南 读音
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桂阳六合土话的“AX了”式状态形容词 被引量:2
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作者 邓永红 《湘南学院学报》 2013年第4期46-52,60,共8页
具有丰富的"AX了"式状态形容词是桂阳六合土话鲜明特色之一,如"红绯了、酸共了、东了、亻松怪了"。详尽搜集考察了六合土话"AX了"式状态形容词,并对其进行了详细的描述。"A"多为形容词性语素。... 具有丰富的"AX了"式状态形容词是桂阳六合土话鲜明特色之一,如"红绯了、酸共了、东了、亻松怪了"。详尽搜集考察了六合土话"AX了"式状态形容词,并对其进行了详细的描述。"A"多为形容词性语素。"X"为后缀,大多数语源不清楚了,只起记音作用。"了"也是后缀,跟六合土话表动作完成或变化已经实现动态助词的读音相同。并通过调查和已有文献了解到"AX了"式状态形容词在湘南土话、西南官话、湘语中均有分布,但数量不一。结论:在同一方言中不同的"AX了"有些是词,有些是短语。 展开更多
关键词 桂阳土话 “AX了”式状态形容词 句法功能 地理分布
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安徽“合六巢”区域旅游资源整合与开发 被引量:3
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作者 尹长丰 《决策咨询通讯》 2009年第4期64-67,共4页
区域旅游整合开发是现代旅游业发展的必然趋势。全面整合旅游资源,联合开发出一个特色鲜明、文化深厚、可游性强的区域性旅游圈,对提高区域旅游竞争力,实现旅游经济可持续发展具有重要意义。在分析了安徽"合六巢"区域旅游资... 区域旅游整合开发是现代旅游业发展的必然趋势。全面整合旅游资源,联合开发出一个特色鲜明、文化深厚、可游性强的区域性旅游圈,对提高区域旅游竞争力,实现旅游经济可持续发展具有重要意义。在分析了安徽"合六巢"区域旅游资源整合可行性的基础上,提出了安徽"合六巢"区域旅游资源整合的具体措施。 展开更多
关键词 “合巢” 旅游资源 开发 研究
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“合六巢”区域旅游资源整合开发研究
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作者 尹长丰 《特区经济》 北大核心 2009年第5期196-197,共2页
区域旅游整合开发是现代旅游业发展的必然趋势。全面整合旅游资源,联合开发出一个特色鲜明、文化深厚、可游性强的区域性旅游圈,对提高区域旅游竞争力,实现旅游经济可持续发展具有重要意义。本文首先分析了"合六巢"区域旅游... 区域旅游整合开发是现代旅游业发展的必然趋势。全面整合旅游资源,联合开发出一个特色鲜明、文化深厚、可游性强的区域性旅游圈,对提高区域旅游竞争力,实现旅游经济可持续发展具有重要意义。本文首先分析了"合六巢"区域旅游资源整合可行性的基础上,提出了"合六巢"区域旅游资源整合的具体措施。 展开更多
关键词 “合巢” 旅游资源 开发 研究.
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Environmentally benign and economic synthesis of covalent triazine-based frameworks 被引量:2
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作者 张玲 刘学 +2 位作者 杨瑞霞 黄年玉 邓伟侨 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第3期583-588,共6页
Covalent triazine-based frameworks(CTFs) are important microporous materials with a wide range of applications.Here,we demonstrate an environmentally benign and economic synthetic pathway to CTFs.The monomers used f... Covalent triazine-based frameworks(CTFs) are important microporous materials with a wide range of applications.Here,we demonstrate an environmentally benign and economic synthetic pathway to CTFs.The monomers used for CTFs,aromatic nitriles,were obtained by cyanation using nontoxic potassium hexacyanoferrate(Ⅱ) in place of commonly used toxic cyanides.Then,the CTFs were synthesized by trimerization of the corresponding cyano monomers in molten zinc chloride.A series of CTFs was synthesized,and the highest Brunauer-Emmett-Teller surface area measured in this series was 2404 m^2/g.Among the synthesized CTFs,CTF_(DCP) exhibited excellent CO_2 adsorption properties,with a CO_2 uptake of 225 mg/g at 0℃. 展开更多
关键词 Covalent triazine-based framework Aryl bromide CYANATION Potassium hexacyanoferrate(Ⅱ) Palladium acetate
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小型水库高产养鱼技术 被引量:1
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作者 张喜富 《农技服务》 2012年第7期876-876,共1页
介绍了小型水库高产养鱼应做到六"合":清野消毒时间要合适;鱼种放养要合理;肥料施用要配合;"三网搭配"要适合;养殖模式要综合;鱼病预防与治疗结合。
关键词 养鱼 小型水库 六“合”
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Synthesis and characterization of porous cobalt oxide/copper oxide nanoplate as novel electrode material for supercapacitors 被引量:2
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作者 张水蓉 胡志彪 +3 位作者 刘开宇 刘艳珍 何方 谢清亮 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第12期4054-4062,共9页
A promising Co3O4/Cu O composite electrode material was successfully synthesized through a facile hydrothermal and calcination process. Effects of the surfactants hexadecyltrimethyl ammonium bromide(CTAB) and polyvi... A promising Co3O4/Cu O composite electrode material was successfully synthesized through a facile hydrothermal and calcination process. Effects of the surfactants hexadecyltrimethyl ammonium bromide(CTAB) and polyvinylpyrrolidone(PVP) on the morphology and electrochemical performance of the composite were investigated. Powder X-ray diffraction(XRD), scanning electron microscopy(SEM), transmission electron microscopy(TEM) and nitrogen adsorption-desorption experiment were employed to characterize the microstructures and morphologies of the composite. Meanwhile, the electrochemical performances of the samples were studied using cyclic voltammetry(CV), galvanostatic charge-discharge test and electrochemical impedance spectroscopy(EIS). The results show that the porous Co3O4/Cu O-CTAB nanoplates own the best performance and exhibits a high specific capacitance of 398 F/g at 1 A/g with almost 100% capacitance retention over 2000 cycles, and it retains 90% of capacitance at 10 A/g. 展开更多
关键词 cobalt oxide/copper oxide composite hexadecyltrimethylammonium bromide(CTAB) polyvinylpyrrolidone(PVP) hydrothermal method SUPERCAPACITORS
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Cu(Ⅱ),Ni(Ⅱ)Complexation with Acid Alizarine Blue B in the Presence of Cetyltrimethylammonium Bromide
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作者 沈荣 郜洪文 俞汉青 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第2期178-182,共5页
The coordination reactions of Cu(Ⅱ) and Ni(Ⅱ) with acid alizarine blue B (AABB) in the presence of cetyltrimethylammonium bromide (CTAB) micelle were investigated using the microsurface adsorptionspectral co... The coordination reactions of Cu(Ⅱ) and Ni(Ⅱ) with acid alizarine blue B (AABB) in the presence of cetyltrimethylammonium bromide (CTAB) micelle were investigated using the microsurface adsorptionspectral correction technique (MSASC). The aggregation of AABB on CTAB followed the Langmuir isothermal adsorption law. The enrichment of AABB on CTAB sensitized the complexation between Cu(Ⅱ) or Ni(Ⅱ)and AABB. The binding ratio of AABB to CTAB was 1:2.5, and monomeric aggregate, AABB2CTAB5, was formed with an adsorption constant of 5.95×10^5 at 20 ℃ or 2.48×10^5 at 40 ℃. In the ternary complexation, the ratio of AABB:Cu and AABB:Ni were 1:1 and 1:2.5, respectively. Two types of aggregates, Cu2.AABB2·CTAB80 and Ni5.AABB2.CTAB80, were formed. 展开更多
关键词 Microsurface adsorption-spectral correction technique Langmuir aggregation Acid alizarine blue B Cetyltrimethylammonium bromide Ternary complex
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Protection behavior of fluorine-containing cover gases on molten magnesium alloys 被引量:4
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作者 熊守美 王先飞 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第7期1228-1234,共7页
The sulphur hexa-fluoride gas(SF6), which is commonly used as the cover gas of molten magnesium alloys in the magnesium industry today, has an extremely high global warming potential(GWP). The protection mechanism... The sulphur hexa-fluoride gas(SF6), which is commonly used as the cover gas of molten magnesium alloys in the magnesium industry today, has an extremely high global warming potential(GWP). The protection mechanism of SF6 containing cover gases on molten magnesium alloys was presented. The cover gas protects the melt by reacting with the melt to form a coherent protective film on the melt surface. The film contains MgO and MgF2. Particles containing MgF2 form on the interface between the oxide film and the bulk magnesium alloy, which correspond to the concave areas from the surface observation. These particles increase the Pilling and Bedworth ratio of surface film and enhance the protective capability of the films. Based on the understanding of the mechanism of SF6, a melting technology in a sealed furnace was proposed, and the protection behavior of magnesium alloys in the sealed melting furnace was investigated under the protective atmosphere containing HFC-134a. The morphology and composition of the surface film were also studied. Experiments to evaluate the protective effect of two other fluorine containing gases with low GWPs on AZglD alloy in the sealed furnace were also carried out, and the results show that the new gases are potential substitutes for SF6. 展开更多
关键词 magnesium alloy melt protection SF6 surface film protection mechanism
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High efficient removal and mineralization of Cr(VI)from water by functionalized magnetic fungus nanocomposites 被引量:3
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作者 CHEN Run-hua CHENG Yu-ying +3 位作者 WANG Ping LIU Zhi-ming WANG Yu-guang WANG Yang-yang 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第5期1503-1514,共12页
A hydroxyl-functionalized magnetic fungus nanocomposite(MFH@GO)was prepared by a simple one-pot method for the removal of Cr(VI)from wastewater.The adsorption behavior of MFH@GO to Cr(VI)in wastewater was discussed in... A hydroxyl-functionalized magnetic fungus nanocomposite(MFH@GO)was prepared by a simple one-pot method for the removal of Cr(VI)from wastewater.The adsorption behavior of MFH@GO to Cr(VI)in wastewater was discussed in detail.At pH of 5.0 and temperature of 323.15 K,MFH@GO had higher adsorption capacity to Cr(VI)(58.4 mg/g)than the unmodified fungus and GO.Fourier transform infrared spectroscopy(FTIR),X-ray diffraction(XRD),thermogravimetry and differential thermal analysis(TG-DTA),scanning electron microscopy and energy dispersive X-Ray spectroscopy(SEM-EDX)were employed to determine the characteristics of MFH@GO.Results showed that magnetic graphene oxide nanoparticles significantly enhanced the physiochemical properties of the fungi.In addition,the adsorption mechanisms analyses show that Cr(VI)could be reduced and mineralized into ferric chromate in residues.These results suggested that MFH@GO could be used as an promising and alternative biosorbent for removal of Cr(VI)from industrial wastewater. 展开更多
关键词 wastewater CR(VI) fungus nanocomposites BIOMINERALIZATION
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Optical Properties of CdS.Nanobelts and Nanosaws Synthesized by Thermal Evaporation Method 被引量:1
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作者 Zhi-wei Peng Bing-suo Zou 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2012年第2期226-230,I0004,共6页
By a simple one-step H2-assisted thermal evaporation method, high quality CdS nanos- tructures have been successfully fabricated on Au coated Si substrates in large scale. The as-synthesized CdS nanostructures consist... By a simple one-step H2-assisted thermal evaporation method, high quality CdS nanos- tructures have been successfully fabricated on Au coated Si substrates in large scale. The as-synthesized CdS nanostructures consisted of sword-like nanobelts and toothed nanosaws with a single-crystal hexagonal wurtzite structure. The deposition temperature played an important role in determining the size and morphology of the CdS nanostruetures. A combination of vapor-liquid-solid and vapor-solid growth mechanisms were proposed to interpret the formation of CdS nanostructures. Photoluminescence measurement indicated that the nanobelts and nanosaws have a prominent green emission at about 512 nm, which is the band-to-band emission of CdS. The waveguide characteristics of both types of CdS nanos-truetures were observed and discussed. 展开更多
关键词 CdS nanostructures Thermal evaporation PHOTOLUMINESCENCE Optical waveguide
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Superlattice Patterns in Coupled Turing Systems 被引量:1
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作者 刘富成 贺亚峰 潘宇扬 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第5期971-976,共6页
In this paper, superlattice patterns have been investigated by using a two linearly coupled Brusselator model. It is found that superlattice patterns can only be induced in the sub-system with the short wavelength. Th... In this paper, superlattice patterns have been investigated by using a two linearly coupled Brusselator model. It is found that superlattice patterns can only be induced in the sub-system with the short wavelength. Three different coupling methods have been used in order to investigate the mode interaction between the two Turing modes. It is proved in the simulations that interaction between activators in the two sub-systems leads to spontaneous formation of black eye pattern and/or white eye patterns while interaction between inhibitors leads to spontaneous formation of super-hexagonal pattern. It is also demonstrated that the same symmetries of the two modes and suitable wavelength ratio of the two modes should also be satisfied to form superlattice patterns. 展开更多
关键词 superlattice pattern turing instability mode interaction
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Synthesis and Crystal Structure of Potassium Triethylenetetraaminehexaacetatodi [Oxo-vanadium(Ⅳ)] Hexahydrate, K_2[V_2O_2(ttha)]·6(H_2O)
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作者 JIANGYa-Qi XIEZhao-Xiong 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2003年第4期423-426,共4页
The title complex, potassium triethylenetetraaminehexaacetatodi [oxo-vanadium (Ⅳ)] hexahydrate K2[V2O2(ttha)]6(H2O), was synthesized in aqueous solution and its crystal structure has been determined by X-ray diffract... The title complex, potassium triethylenetetraaminehexaacetatodi [oxo-vanadium (Ⅳ)] hexahydrate K2[V2O2(ttha)]6(H2O), was synthesized in aqueous solution and its crystal structure has been determined by X-ray diffraction. The complex belongs to a triclinic system, space group P?with a = 6.645(1), b = 9.870(2), c = 13.263(3) ? a = 70.68(3), b = 76.27(3), g = 71.66(3), V = 770.5(3) 3, Mr = 808.58, Dc = 1.743 g/cm3, Z = 1, m = 0.968 mm-1, l(MoKa) = 0.71073 and F(000) = 416. The final R = 0.0465 and wR = 0.1091 for 2974 observed diffractions with I ≥ 2s(I). In the complex, the V atom is octahedrally coordinated to the oxo ligand, two N and three O atoms of the triethylenetetraaminehexaacetic (TTHA) ligand. All of the ten chelating sites are coordinated to the two vanadium atoms, and the coordination octahedron is distorted. Each [V2O2(ttha)]2- ion is further connected by the K+ ions through carboxyl groups of TTHA6- ion, forming a two dimensional network structure. 展开更多
关键词 VANADIUM COMPLEX TTHA crystal structure
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Fully Quantized Theory of Six-Wave Mixing with Matter Waves
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作者 ZHOU Qing Ping 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第2期477-478,共2页
We show that Wu-Yang theory of fully quantized four-wave mixing can be generalized to the six-wave mixing and derive the analytical solution of the coupled equations describing the quantum dynamics of six-wave mixing.
关键词 multiwave mixing fully quantized theory matter waves
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Synthesis and Crystal Structure of a New Hexadentate Ligand N,N'-Bis(di(2-pyridyl)methyl)ethylenediamine
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作者 YEBao-Hui CHENXiao-Ming 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第3期242-246,共5页
The reaction of di(2-pyridyl)ketone with ethylenediamine produced hexadentate Schiff base 1 which can be reduced to form a new ligand N,N-bis(di(2-pyridyl)-methyl)ethylene- diamine (BDPM) in ethanol solution. The two ... The reaction of di(2-pyridyl)ketone with ethylenediamine produced hexadentate Schiff base 1 which can be reduced to form a new ligand N,N-bis(di(2-pyridyl)-methyl)ethylene- diamine (BDPM) in ethanol solution. The two compounds were characterized by elemental analyses and spectroscopic methods. Their structures were determined by X-ray diffraction study. Crystal data for 1: C24H20N6, Mr = 392.5, monoclinic, P21/c, a = 13.871(3), b = 13.510(2), c = 12.153(2) ? b = 112.97(2)? Z = 4, V = 2094.1(6) ?, Dc = 1.245 g/cm3, m(MoKa) = 0.078 mm-1, F(000) = 824, the final R = 0.0545 and wR = 0.0557 for 2048 observed reflections (I > 2s(I)); for BDPM: C24H24N6, Mr = 396.49, monoclinic, C2/c, a = 21.411(3), b = 8.053(1), c = 11.868(1) ? b = 92.63(1)? Z = 4, V = 2044.2(4) 3, Dc = 1.288 g/cm3, m(MoKa) = 0.080 mm-1, F(000) = 840, the final R = 0.0401 and wR = 0.0939 for 1673 observed reflections (I > 2s(I)). 展开更多
关键词 synthesis crystal structure hexadentate ligand di-2-pyridyl ketone
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Hexanuclear ring cobalt complex for photochemical CO_(2) to CO conversion 被引量:1
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作者 Xiangyu Meng Rui Li +6 位作者 Junyi Yang Shiming Xu Chenchen Zhang Kejia You Baochun Ma Hongxia Guan Yong Ding 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第9期2414-2424,共11页
Photosynthesis in nature has been deemed as the most significant biochemical reaction,which maintains a relatively stable content of O_(2) and CO_(2) in the atmosphere.Herein,for a deeper comprehension of natural phot... Photosynthesis in nature has been deemed as the most significant biochemical reaction,which maintains a relatively stable content of O_(2) and CO_(2) in the atmosphere.Herein,for a deeper comprehension of natural photosynthesis,an artificial photosynthesis model reaction of photochemical CO_(2) to CO conversion(CO_(2)+2 H^(+)+2e^(-)→CO+H_(2)O)catalyzed by a homogeneous hexanuclear ring cobalt complex{K_(2)[CoO_(3)PCH_(2)N(CH_(2)CO_(2))_(2)]}_(6)(Co6 complex)is developed.Using the[Ru(bpy)_(3)]^(2+)as a photosensitizer and TEOA as a sacrificial electron donor,an optimal turnover frequency of 503.3 h^(‒1) and an apparent quantum efficiency of 0.81%are obtained.The good photocatalytic CO_(2) reduction performance is attributed to the efficient electron transfer between Co6 complex and[Ru(bpy)_(3)]^(2+),which boosts the photogenerated carriers separation of the photosensitizer.It is confirmed by the j‐V curves,light‐assisted UV‐vis curves,steady‐state photoluminescence spectra and real‐time laser flash photolysis experiments.In addition,the proposed catalytic mechanism for CO_(2) reduction reaction catalyzed by the Co6 complex is explored by the potassium thiocyanate poison experiment,Pourbaix diagram and density functional theory calculations. 展开更多
关键词 PHOTOSYNTHESIS Homogeneous catalysis CO_(2)reduction reaction Density functional theory Hexanuclear ring cobalt complex
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Lubrication properties of silver-palladium alloy prepared by ion plating method for high temperature stud bolt 被引量:2
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作者 Jung-Dae KWON Sunghun LEE +3 位作者 Koo-Hyun LEE Jong-Joo RHA Kee-Seok NAN Se-Hun KWON 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第A01期12-16,共5页
As a solid lubricant, silver-palladium (Ag-Pd) alloy coating was investigated for the application to high temperature stud bolt. A glue layer nickel (Ni) film was deposited on the surface of the hex bolt sample and th... As a solid lubricant, silver-palladium (Ag-Pd) alloy coating was investigated for the application to high temperature stud bolt. A glue layer nickel (Ni) film was deposited on the surface of the hex bolt sample and then Ag-Pd alloy coating was performed on it using ion plating method. The friction coefficient of Ag-Pd alloy film coated bolt was lower than that of N-5000 oil coated bolt by the result of axial force measurement. The cyclic test of heat treatment was conducted to evaluate the durability of Ag-Pd alloy film coated bolt. In a cycle, sample was assembled into the block using torque wrench, followed by heating and disassembling. It was not successful to disassemble the N-5000 oil coated bolt from the block after only one cycle. However, the Ag-Pd alloy film coated bolt was able to be disassembled softly till 12 cycles. 展开更多
关键词 solid lubricant silver-palladium alloy ion plating
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Synthesis and Crystal Structure of[Na(DB18C6)(H_2O)_2]_2Mo_6O_(19)·3DMF·2CH_3OH 被引量:2
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作者 Lu Xiao-Ming Zhao Ya-Ping +2 位作者 Qu Er-Ling Xiao Ling-Mei Liu Shun-Cheng(Department of Chemistry, Capital Normal University, Beijing, 100037)Jin Xiang-Lin(Institute of Physical Chemistry, Beijing Uniuersity, Beijing, 100871) 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1996年第4期293-296,共4页
The title complex [Na (DB_18C_6) (H_2O)_2]_2Mo_6O_19·3DMF · 2CH_3OH (Ⅰ) , a new type of crown hexamolybdate supermolecule, has been synthesized. Its crystal structure has been determined by X-ray diffractio... The title complex [Na (DB_18C_6) (H_2O)_2]_2Mo_6O_19·3DMF · 2CH_3OH (Ⅰ) , a new type of crown hexamolybdate supermolecule, has been synthesized. Its crystal structure has been determined by X-ray diffraction analysis. The crystal C_49H_32 Mo_6N_2Na_2O_40 is tetragonal, space group P4/mbm, a= 17.108(2), c= 28. 285 (6) A ,V=8279(2) A ̄ 3, Z=4 , M_r= 1960. 8 , D_x=1. 573 g/cm ̄3 , P=9. 51cm ̄(-1). F(000)=3936. The final agreement factors R=0. 058 and R_w= 0. 062 for 1777 independent reflections with F>4σ(F). In contrast to what we have reported about [Na(DB_18C_6)(CH_3OH)]_2Mo_6O_19(Ⅱ) where the whole complex was linked together, the cation [Na (DB_18C_6 ) (H_2O)_2] ̄ + , that has crystallographic D_2h symmetry, combines with the anion with the symmetry O_h by electronic interaction. 展开更多
关键词 hexamolybdate anion crown ether complex crystal structure
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段玉裁的古音体系及其对方音的态度
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作者 乔全生 《西南交通大学学报(社会科学版)》 2020年第4期34-43,共10页
段玉裁古音体系体大思精,《六书音均表》即是段氏潜心商订的古音学力作,形成了段氏古音学的完整体系,但是书中几乎不提方言,而是用合韵说解释异部相押。事实上,段氏并非没有方音观念,其拒斥方音完全是出于维护同质性理想化古音体系的考... 段玉裁古音体系体大思精,《六书音均表》即是段氏潜心商订的古音学力作,形成了段氏古音学的完整体系,但是书中几乎不提方言,而是用合韵说解释异部相押。事实上,段氏并非没有方音观念,其拒斥方音完全是出于维护同质性理想化古音体系的考虑,"今韵古分十七部表"就是其同质性理想化古音体系的重要显现。然而,同质性理想化的语音体系会导致古音体系的严重缺陷,如:韵类关系古今无变、在今音中寻求古音音值、拒斥以个别字的流变审取古音的方音说。 展开更多
关键词 音韵学 古音学研究 段玉裁 古音体系 方音 韵说 书音均表》
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Effects of h-BN content on properties of Ni-Cr/h-BN composite 被引量:1
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作者 韦小凤 王日初 +2 位作者 冯艳 彭超群 朱学卫 《Journal of Central South University》 SCIE EI CAS 2011年第5期1334-1339,共6页
Ni-Cr/h-BN self-lubricating composities were prepared by powder metallurgy (P/M) method.The effects of hexagonal boron nitride (h-BN) content on the mechanical and tribological properties of the Ni-Cr/h-BN composites ... Ni-Cr/h-BN self-lubricating composities were prepared by powder metallurgy (P/M) method.The effects of hexagonal boron nitride (h-BN) content on the mechanical and tribological properties of the Ni-Cr/h-BN composites were investigated.The corresponding frictional models were established to analyze the formation of the lubricant h-BN films on the surfaces of the Ni-Cr/h-BN composites.The results show that,when the content of h-BN increases from 5% to 15% (mass fraction),the bending strength of the Ni-Cr/h-BN composite decreases from 96.670 MPa to 17.319 MPa,and the hardness (HB) decreases from 33 to 14.The friction coefficient of the Ni-Cr/h-BN composite decreases firstly from 0.385 to 0.216,and then increases to 0.284,while the wear rate decreases firstly from 4.14×10-9 kg/(N·m) to 1.35×10-9 kg/(N·m),then increases to 2.36×10-9 kg/(N·m).The best comprehensive mechanical and tribological properties can be obtained between 10% and 12% h-BN addition. 展开更多
关键词 Ni-Cr/h-BN composite hexagonal boron nitride solid lubricating film friction coefficient wear rate
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