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Infrared (IR) absorption spectra and X-ray powder diffraction (XRD) patterrns of sexpenfine cat's eye from Sichuan Province have been investigated, and infrared absorption bands of the serpentine have been assigned in this paper. The results indicate that the bands near 3 600 - 3 700 cm^-1 belong to the stretching absorption band VOH, the bands in 948 - 1 100 cm^-1 axe assigned to the stretching vibraling band Usvo, and the bands at 600 570 and 440 cm^-1 respectively belong to the bending vibration band VOH, δMg-O and δSi-O. The serpentine cat' s eye includes two types: chrysotile and antigorite. Chrysotile has a sharp and intensive band at 3 688 cm^-1 and a weak band at 3 643 cm^-1 , while antigorite has only one intensive band in the region. At vibration band VSi-O, chrysotile and antigorite have a similar feature at 1 071 cm^-1, but the band at 980 cm^-1 in anfigorite has been split into two bands in chrysotile - a strong one at 1 027 cm^-1 and a weak one at 949 cm^-1. In addition, antigorite has a characteristic bending vibrating band δMg-O at 570 cm^-1. Based on the analysis of the feature of crystal structure, their IR differences axe well explained.  相似文献   
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1 Introduction Becauseofthecombinationofanumberoffavorableproperties,suchashighhardness,highcarriermobilityandbreakdownvoltage,largebandgap ,lowdielectricconstant,andtransparencytovisiblelight,IRlightandmicrowaves,etc.[1] ,diamondfilmhasbeenconsider ablyprom…  相似文献   
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1IntroductionThe synthesis and characterization of nano-struc-tured materials are the subject of intense current re-search.Hyperfineγ-Fe2O3particle with good perfor-mance,such as magnetism,catalysis,gas-sensitivityand so on,are widely applied in various fields[1].It ishighly significant to research and develop the methodsfor synthesis of nanometerγ-Fe2O3.With the development of nano-science and nano-technology,the methods for preparation ofγ-Fe2O3have been greatly progressed,for example,…  相似文献   
4.
The preparation of nanometer γ-Fe2O3 through an electrochemical process was studied at room temperature, using a metal iron plate as sacrificing anode and a sheet of stainless steel as cathode, in non-aqueous mediate containing ( Bu)4 NBr as support electrolyte and 2 % (vol % ) water. The powdery particles obtained were then calcined at 300 ℃. The products were characterized by IR, XRD,SEM, TEM and laser particle size analyser, indicating the fine particle is a pure nanometer γ-Fe2O3. The morphology is like coneshaped and their average size is 22.0 nm. Furthermore the VSM spectrum shows that the particle's coercivity (3.9 × 103 A/m) is rather small, presenting the excellent super-paramagnetism.  相似文献   
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1IntroductionSerpentine used as inorganic material inindustry hasbeeninvestigated for many years[1-3].But there are noreports on serpentine cat’s eye owing to its rarity.During our recent field investigation in Sichuan Prov-ince,southwest of China,for the first ti me we discov-ered the rare serpentine cat’s eye with well-growntex-ture and,if properly polished,a vivid cat eye effect(see Fig.1).Weng,et al.[4]also reported the newdiscovery of nephrite cat’s eyes inthis region.Serpen-tine can…  相似文献   
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In this paper, a novel approach for highly efficient purification of cadmium by vacuum distillation was reported. During the cadmium vacuum distillation, a small quantity of cadmium oxide film, produced under lower vacuum, was intentionally induced into the evaporator, and the presence of cadmium oxide changed the behavior of impurities. Meantime, a thermodynamic model of the process, which described the phase composition in the evaporator and condenser during evaporation of cadmium, was established. The model was used to classify the impurities according to their behavior in the purification process. On the base of the model, the purification of cadmium by one-stage and two-stage distillation and the validity of the model were also discussed.  相似文献   
7.
Micro-indention and finite element method (FEM) are used to study the stress at the interface between diamond-like carbon (DLC) film and mercury cadmium telluride (MCT) substrate, with different coating thickness, deposition temperature and indention load. The FEM simulation results show that when Young's modulus ratio of the coating to the substrate Ec/Es相似文献   
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lintroductionDiamondisawide-band-semiconductorwithauniquealldextraordinalycombinationofelectronicpropelties(highbreakdownvoltagel"'l,electron/holemobilityl']andcall.iel'saturationvelocityl#]),mechanicalpropelties(highhardnessandstrength)andotherproperties…  相似文献   
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