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1.
用喷雾热解法制备出厚为2000A的掺Cr的Al2O3薄膜。XRD和XPS分析证明其为无定形的Al2-xCrxO3(x=0.072),SEM和椭圆仪分析结果验证了薄膜的均匀性。该薄膜表现出良好的绝缘性质和抗腐蚀性能。  相似文献   

2.
Ba,Sr,Ca在Co/γ—Al2O3催化剂上CO氧化的作用机制(II)   总被引:2,自引:0,他引:2  
用硝酸盐水溶液等量共浸法制备了分别在750℃和900℃焙烧的系列催化剂Co-M/γ-Al2O3(M=Ca,Sr,Ba,Co3O4/Al2O3=8wt%,M/Co=15mol%)测定了CO氧化转化率,用BET表面,XRD,XPS,DTA和TPR等手段研究了助剂Ba,Sr,Ca的作用,结果表明,加入助剂后,CO完全转化温度下降了20~60℃左右,助剂的作用顺序为Ca>Sr>Ba,实验表明,750℃和9  相似文献   

3.
ELECTRONMOMENTUMSPECTRAOFEXCITEDHe(21S)ANDHe(23S)ChenZhangjinShiQicunChenJiXuKezunDepartmentofModernPhysics,UniversityofScien...  相似文献   

4.
应用 ̄1HNMR技术推定了新合成的二(3-取代X基-2,4-戊二酮).N-甲基乙二胺合钴(Ⅲ)配合物:[Co(Xacac)_2(Me-en)]ClO_4(X=CH_3、Cl、NO_2)的Δ(R)∧(S)和Δ(S)∧(R)异构体的空间构型,测定了各配合物异构体手性配位氮原子上的重氢化速率常数k_D值(34.0℃).结果表明,取代基X对k_D值有着显著影响。  相似文献   

5.
DYNAMICDESCRIPTIONOFIONCLOUDINRFTRAPManBaoyuan1WangXiangtai2HuXierong1ZhuJunkong21DepartmentofOpticsofShandongUniversityJina...  相似文献   

6.
本文应用SCC-DV-Xa方法计算了(RSi)4Se6,(RSi)2Se3和R4Si3Se4(R=CH3,C2H5,Ph)等分子簇的结合能,轨道能级,电荷分布,状态密度,分析了簇的稳定性,NMR化学位移,紫外可见吸收和催化性能等,结果与实验相符。  相似文献   

7.
PdO引入对CuO/γ—Al2O3催化剂结构与性能的影响   总被引:1,自引:0,他引:1  
运用PTR,SEM,XRD阶梯扫描及CO和CH4氧化活性测定表征技术研究了CuO/γ-Al2O3催化剂及负载PdO对催化剂性能的影响。结果表明,CuO/γ-Al2O3催化剂上引入不同含量的PdO,使TPR还原峰温欠下降。对载体上CuO平均晶粒大小的测定表明随PdO含量的增加,CuO平均晶粒逐渐减小;SEM对PdO-CuO/γ-Al2O3催化剂上Cu元素分布的面扫描测定亦证实了随PdO含量的增加,催  相似文献   

8.
SnO2-TiO2复合颗粒的形态结构及其光催化活性   总被引:13,自引:0,他引:13  
在气溶胶反应器中,利用TiCl4高温氧化反应制备超细TiO2,采用均匀沉淀法在TiO2表面沉积SnO2制备SnO2-TiO2复合颗粒,应用TEM、EEDS、SRD、BET比表面积测试等手段对粒子进行表征。以活性艳红X-3B复合颗粒,应用TEM、EDS、XRD、BET比表面积测试等手段对粒子进行表征。以活性艳红X-3B溶液为处理对象考察复合颗粒的光催化活性。结果表明SnO2-TiO2复合颗粒的光催化  相似文献   

9.
Ni(II)与壳聚糖的配位作用及其催化性质的研究   总被引:7,自引:0,他引:7  
用ESR、XPS、IR、UV-Vis、DTA-TG和电导率法研究Ni(Ⅱ)与壳聚糖(CS)的配位作用、所形成的配位聚合物(配聚物)的组成和结构。确定Ni(Ⅱ)与CS分子以配位键相结合形成高自旋Ni-CS配聚物,配聚物的配位单元由1个Ni(Ⅱ)与3个CS单体单元的氨基N原子和仲羟基O原子形成扭曲的六配位的八面体结构所组成。此外,对Ni-CS配聚物与Na2SO3体系在MMA聚合中的催化性质进行了研究。  相似文献   

10.
书评     
书评AIPHANDBOOKOFCONDENSERMICROPHONESTheorxCalibrationandMeasurementsGeergeS.K.Wong,TOnyF.W.Embleton主编321+XVll页(AmericanInstitu...  相似文献   

11.
K2O-ZnO-Al2O3-B2O3-SiO2系掺Cr3+透明莫来石微晶玻璃的研究   总被引:1,自引:0,他引:1  
采用了X射线衍射、透射电镜和吸收光谱及荧光光谱技术研究了K2O-ZnO-Al2O3-B2O3-SiO2系掺Cr^3 玻璃的析晶性能和光谱。研究结果表明:在K2O-Al2O3-B2O3-SiO2系掺Cr^3 玻璃的基础上引入ZnO后,析晶性能明显改善;析晶温度降低,析出的纳米莫来石微晶均匀、规则;微晶玻璃的发光强度明显增强。  相似文献   

12.
巴里坤县位于新疆东部哈密地区,是连接内地与北疆的重要通道,巴里坤县境内的石人子沟遗址群是新疆东天山地区的古代游牧民族大型聚落遗址,其中西沟遗址M1墓和石人子沟遗址M011墓分别出土了一批战国晚期至西汉早期的古代玻璃珠,为了解这批玻璃珠的来源,采用激光剥蚀电感耦合等离子体发射光谱(LA-ICP-AES)和激光拉曼光谱(LRS)方法对这两批玻璃珠样品进行化学成分分析。结果表明,西沟遗址M1墓出土玻璃珠均为钠钙玻璃体系,以植物灰作为助熔剂,同时其中七件绿色玻璃珠样品均以锑酸铅作为乳浊剂;石人子沟遗址M011墓出土玻璃珠均为铅钡玻璃体系,以含铅矿物作为助熔剂。与同时期其他已经发表的玻璃数据进行比较,显示西沟遗址出土玻璃珠在成分上与美索不达米亚及古埃及钠钙玻璃不同,推测西沟遗址出土玻璃珠在中亚或新疆地区制作而成;石人子沟遗址出土玻璃珠的化学组成相对集中,应在同一地点制作而成,可能为中原地区传入。本研究证实了新疆巴里坤地区是古代东西方物质文化交流的重要节点,而游牧民族在玻璃制品传播和交流过程中扮演着重要的角色。  相似文献   

13.
Optically transparent Er3+-doped tellurite-based nanocrystallized glasses with the composition of 70TeO2·15Lie2O·0·15Nb2O5·0.5Er2O3(mol)have been perpared by a conventional melting quenching and the subsequent heat treatment porcesses.The sizes of grown nanocrystals in glass matrix appear to be35-50 nm from the X-ray diffraction (XRD) measurement. The microhardness measurement shows that the Vickers hardness values of the nanocrystallized tellurite glasses are larger (33%-62%) than those inthe base glass. The Raman spectra imply that the maximum phonon energy of the based glass decreases and shifts from 668 to 638 cm-1 after heat-treatment. Visible upconversion luminescence and infrared luminescence of the base glass and heat-treated glasses under 980-nm laser diode (LD) excitation are investigated. The 524-, 546- and 656-nm upconversion intensities by 980-nm pumping increase significantly.  相似文献   

14.
用溶胶-凝胶法制备以Eu-苯甲酸-1,10-菲咯啉为掺杂剂的SiO2,SiO2-B2O3和SiO2-B2O3-Na2O为基质的发光材料.材料经1000℃退火处理后,结构十分稳定.通过激发光谱和发射光谱、红外光谱、TEM、XRD研究了基质结构对Eu3 发光性能的影响.结果显示:在589和614 nm处显示Eu3 的特征发射带,对应于Eu3 的5D0→7Fj(j=1,2)跃迁;与直接掺入EuCl3的玻璃材料相比,以Eu-苯甲酸-1,10-菲咯啉为掺杂剂的玻璃材料,虽然Eu的掺杂量较小,但Eu的发光强度较大.与以SiO2为基质的玻璃材料相比,以SiO2-B2O3为基质的玻璃材料Eu3 的发光减弱,其红外光谱显示形成Si-O-B键,说明该结构对Eu3 的发光有猝灭作用,以SiO2-B2O3-Na2O为基质的玻璃材料Eu3 的发光明显增强,其红外光谱显示不存在SiOB键的振动吸收,可能是Na取代B的位置,形成Si-O-Na键,此结构对Eu3 的发光有一定的增强作用.  相似文献   

15.
A total of 46 stratified glass eye beads in Hubei Provincial Museum, Wuhan, China were analyzed in situ by means of portable X‐ray fluorescence and Raman spectrometers. These beads were excavated from the famous tomb of Marquis Yi of the Zeng State, which was dated back to the early Warring States Period (433 bc or little late), in Hubei Province. It is determined that most of these elegant glass beads belong to the typical soda‐lime‐silicate glasses with low contents of MgO and K2O. The colorants used within these beads are attributed to two types: antimony‐based compound opacifiers/colorants and the transition metals in their oxidized state such as Co, Cu, and Fe ions. According to their characteristics of typology, chemical composition, and micro‐crystals within samples, we classified them into three subtypes and evaluated the possible relations among them. In addition, through comparing with the similar contemporary samples unearthed from Xu Jialing Tomb (5th–4th century bc ) in Henan Province, we discussed the provenance of these stratified glass eye beads and relative issues briefly. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

16.
在硅片上沉积厚二氧化硅的火焰水解法研究   总被引:6,自引:1,他引:5  
用火焰水解和高温烧结的方法在单晶硅基片上制备了厚SiO2和B2O2-P2O2-SiO2光波导包层材料。并用扫描电镜(SEM)和X射线粉末衍射(XRD)方法对其微观形貌和物相结构进行了观察和检测。重点对硅基片上沉积厚SiO2时的龟裂和析晶问题进行了深入研究。从扫描电镜照片可以看出.火焰水解法形成的SiO2粉末呈多孔的蜂窝状结构。这种粉末具有很高的比表面积,因而很容易烧结成玻璃。X射线衍射图谱表明.这种粉末是完全非晶态的。经过烧结以后,从扫描电镜照片可以明显看出硅基片上的SiO2薄膜出现龟裂。同时,X射线衍射测试结果表明有少量SiO2析晶。而通过在SiO2中掺入B2O3、P2O5,上述龟裂和析晶完全消失。用这种工艺制备的SiO2波导包层材料厚度达到20μm以上,表面光滑、没有龟裂,而且是完全玻璃态的,可以用于制备性能优良的各种硅基二氧化硅波导器件。  相似文献   

17.
Cadmium telluride nanocrystals that form in the TeO2-Li2O-B2O3-P2O5 glass matrix have been synthesized and studied.They are investigated by X-ray diffraction(XRD),optical transmission and infrared spectroscopy.It has been shown that the long annealing time effect on present samples leads to the growth of CdTe nanoparticles and an increase of tellurium oxide on the surface of nanocrystallites.On the other hand,the infrared spectroscopy shows that the phosphate and borate networks of the glass matrices are mo...  相似文献   

18.
光热敏折变玻璃及其布拉格体光栅特性研究   总被引:3,自引:1,他引:2  
熊宝星  袁孝  张翔  封建胜  张桂菊  邹快盛 《光学学报》2012,32(8):816001-137
采用高温二次化料的方法制备了一种SiO2-Al2O3-ZnO-Na2O(F、Br)玻璃体系的光热敏折变(PTR)玻璃,通过紫外曝光、透射率光谱、X射线衍射(XRD)和差热分析等方法研究了其光热敏析晶机理。研究表明,PTR玻璃的光敏区为280~350nm,工作区为400~2700nm,最佳成核温度和析晶温度分别为490℃和595℃,析晶组分为NaF晶体。采用双光束干涉方法与"两步法"的热处理工艺在PTR玻璃中制备了周期为1000mm-1的布拉格体光栅,光栅的相对衍射效率达到91%,并验证了制备的布拉格体光栅具有角选择滤波能力。  相似文献   

19.
Oblate seed beads (2–4 mm) excavated on Mapungubwe hill, an Iron Age site in South Africa, were analysed with Raman microscopy and supportive techniques to determine the glass technology and pigments used to produce the beads. The Raman spectra and XRF analysis of the beads classify the glass as a typical soda/lime/potash glass similar to Islamic glass from the 8th century (Ommayad), but with higher levels of aluminium, iron and magnesium. The turquoise, bright green, bright yellow and orange colours were obtained by utilizing a combination of cassiterite (SnO2) and lead tin yellow type II (PbSn1−xSixO3). Doping with cobalt and manganese produced dark blue and plum‐coloured beads. The Fe‐S chromophore was detected through its resonance‐enhanced spectrum in the black beads. Corrosion of the black beads was investigated and an organic phase detected on the beads, which might have influenced the corrosion process. This detailed profile of the glass technology used to produce the Mapungubwe oblates might eventually help to determine their provenance. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   

20.
利用Raman光谱、X射线衍射(XRD)和热分析(DSC)技术研究了包容TiO2的磷酸钙玻璃的结构特点.结果表明,TiO2添加量小于3 mol%时,与磷酸钙形成均质玻璃.添加量为6~12 mol%时,玻璃基体中生成了Ca2P2O7和CaTi4(PO4)6品相.随着TiO2的加入,玻璃体系中发生了偏磷酸盐向焦磷酸盐和正磷酸盐的结构转变.TiO2添加量小于3 mol%时,加入TiO2增强了玻璃结构的内聚力,使得玻璃转变温度逐渐提高,玻璃的热稳定性增强.  相似文献   

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