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51.
电子衍射实验数据的采集与处理   总被引:5,自引:1,他引:5  
潘学军  吴倩 《物理实验》2004,24(6):26-28
使用数码相机拍摄采集电子衍射图片 ,利用Excel处理软件及绘图工具进行数据测量与处理 ,提高了实验效率  相似文献   
52.
Shan-Shan Wang 《中国物理 B》2021,30(11):118501-118501
Design and simulation results of a novel multifunctional electronic calibration kit based on microelectromechanical system (MEMS) single-pole double-throw (SPDT) switches are presented in this paper. The short-open-load-through (SOLT) calibration states can be completed simultaneously by using the MEMS electronic calibration, and the electronic calibrator can be reused 106 times. The simulation results show that this novel electronic calibration can be used in a frequency range of 0.1 GHz-20 GHz, the return loss is less than 0.18 dB and 0.035 dB in short-circuit and open-circuit states, respectively, and the insertion loss in through (thru) state is less than 0.27 dB. On the other hand, the size of this novel calibration kit is only 6 mm×2.8 mm×0.8 mm. Our results demonstrate that the calibrator with integrated radio-frequency microelectromechanical system (RF MEMS) switches can not only provide reduced size, loss, and calibration cost compared with traditional calibration kit but also improves the calibration accuracy and efficiency. It has great potential applications in millimeter-wave measurement and testing technologies, such as device testing, vector network analyzers, and RF probe stations.  相似文献   
53.
石俊杰  吴倩 《物理通报》2023,(8):136-139
介绍了GeoGebra软件解决杠杆动态平衡问题中的3类情形,借助其极佳的动态性,使相应的动态平衡过程形象地显示出来,突破这一教学难点,消除或降低学生的理解难度.  相似文献   
54.
CommentThestructuralintheinorganonickelperchlorateiswelldocumented[1,2].Amongthese,thestructuresinwhichperchlorateanionactsasatridentateligandareratherrare.Toourbestknowledge,inorganonickelperchloratecompoundcontainingtridentateperchlo鄄rateandtridentateh…  相似文献   
55.
Green single crystal of the title compound was accidentally obtained by the reaction of N,N′-bis(pyridylcarbonyl)-4,4′-diaminodiphenyl ether (L) with nickel perchlorate. In the structure of [Ni( μ3-OH)( μ3-ClO4)(H2O)]n, the local coordinating geometry around Ni center displays a distorted octahedron in which one coordination site of each metal atom was occupied by a water molecule. Each perchlorate anion and hydroxyl group acts as a tridentate bridging spacer to bind three Ni atoms, thus resulting in the formation of two-dimensional layered network. CSD: 414263.  相似文献   
56.
袁荣鑫  叶琼  吴倩  熊仁根 《无机化学学报》2004,20(12):1504-1506
An unexpected but welcome compound 1 obtained through organic synthesis, can find a lot of applications in electrochemistry, industrial extracting agent for gold and antiwear additive in lubricating oil. The Ni center in compound 1 has an octahedral geometry with a tetramethylammonium cation as a charge balance. CCDC: 252203.  相似文献   
57.
The triphenyltin complex with salicylidene-2-aminophenol(C_(31)H_(24)NO_2Sn,1)has been synthesized and characterized by elemental analysis,IR spectroscopy,thermogravimetric analysis,and X-ray single-crystal diffraction.The complex crystallizes in monoclinic system,P2_1/c space group with a=1.09515(8),b=1.17739(8),c=2.29075(14)nm,β=117.070(4)°,V=2.6302(3)nm~3,Z=4,D_c=1.417 g/cm~3,?=0.999 mm~(–1),F(000)=1123,R=0.0472 and w R=0.1169.X-ray single-crystal diffraction showed that 1 demonstrates a one-dimensional chain structure.The quantum chemical calculation of 1 has been investigated.Complex 1 emits fluorescence at 558 nm and exhibits certain inhibitory activity against NCI-H460,A549 and MCF-7.  相似文献   
58.
以HY分子筛和硝酸盐[M(NO3)2,M=Ni,Zr,Ca和Ce]为原料,通过浸渍法制得改性HY型分子筛(M/HY)催化剂,其结构和性能经XRD,比表面积,IR和SEM表征。考察了M/HY催化重质油轻质化的效果,结果表明,稀土金属的添加使重质油转化率得到了提高,平均转化率均在40%以上。从总选择性以及类汽油选择性来看,其中Ni/HY活性较好,类汽油选择性平均值为53.98%,最高达72.56%,选择性均优于HY分子筛(21.32%)。  相似文献   
59.
通过对陶器中酒类残留的检测分析,介绍了化学技术手段在考古工作中的应用。在实验中,学生通过萃取、抽滤、离心、旋转蒸发等实验步骤提取酒的标志物——有机酸,并对其进行高效液相色谱(HPLC)检测,最后结合陶片的考古背景分析陶片的可能用途。该实验依托于考古化学这一新兴交叉学科,面向化学、考古学等专业的学生开设,有助于学生了解并掌握分析化学中样品分离和制备、液相色谱分析等基本概念与操作,并对考古学的研究内容形成一定认识。  相似文献   
60.
以柠檬酸为络合剂,采用溶胶-凝胶法制备了一系列双钙钛矿型催化剂La_2NiBO_6(B=Mn,Fe,Co,Cu,Ce),其结构经SEM,XRD,N2-BET和H2-TPR表征。以甲烷燃烧反应为模板反应,研究了La_2NiBO_6的催化性能。结果表明:La_2NiCeO_6催化性能最好,起燃温度T_(10%)为461℃,最终转化温度T_(90%)为565℃。  相似文献   
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