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231.
I. Grabec 《The European Physical Journal B - Condensed Matter and Complex Systems》2001,22(1):129-135
A physical law is represented by the probability distribution of a measured variable. The probability density is described
by measured data using an estimator whose kernel is the instrument scattering function. The experimental information and data
redundancy are defined in terms of information entropy. The model cost function, comprised of data redundancy and estimation
error, is minimized by the creation-annihilation process.
Received 24 February 2000 and Received in final form 21 February 2001 相似文献
232.
This paper describes the development of a non-contact system for measuring colour of printed material at web speeds. The system proposed uses a non-contact spectrophotometer based on a holographic grating, in conjunction with a conventional monochrome area scan camera, from which colour spectral data is extracted, whilst a xenon flash is used to illuminate colour samples. Software and hardware details of the system are given, along with the underlying mathematics for colour space conversion and measurement. Conversion equations from X, Y, Z chromaticity co-ordinates to the RGB system are presented, and also equations to convert from the L*a*b* colour space to X, Y, Z chromaticity co-ordinates. Experimental results are presented whereby the non-contact spectral system is shown to perform to a colour tolerance exceeding that of conventional colour video systems. 相似文献
233.
G A V Ramanamurthy K Ramachandra Rao Y Rama Krishna P Venkateswarlu K Bhaskara Rao P V Ramana Rao S Venkata Ratnam V Seshagiri Rao G J Nagaraju S Bhuloka Reddy 《Pramana》2001,56(5):697-703
The Measurement of K
β
K
/α
intensity ratios are measured in some 3d shell elements by using a 2 MeV proton beam along with a high resolution Si(Li) detector. The present Measurement of K
β
K
/α
intensity ratios are in good agreement with Scofield modified theoretical values, thus supporting the basic assumptions in
that theory. From the present Measurement of K
β
K
/α
intensity ratios, it is evident that due to chemical effects, the experimental Measurement of K
β
K
/α
intensity ratios will be increased while they will be decreased due to the presence of simultaneous M-shell vacancies which are produced due to proton excitation. 相似文献
234.
Dean A. Flinchbaugh L. F. Crawford David Bradley 《Accreditation and quality assurance》2001,6(12):493-500
A model is presented that correlates historical proficiency test data as the log of interlaboratory standard deviations versus
the log of analyte concentrations, independent of analyte (measurand) or matrix. Analytical chemistry laboratories can use
this model to set their internal measurement quality objectives and to apply the uncertainty budget process to assign the
maximum allowable variation in each major step in their bias-free measurement systems. Laboratories that are compliant with
this model are able to pass future proficiency tests and demonstrate competence to laboratory clients and ISO 17025 accreditation
bodies. Electronic supplementary material to this paper can be obtained by using the Springer LINK server located at http://dx.doi.org/
10.1007/s007690100398-y.
Received: 31 March 2001 Accepted: 11 September 2001 相似文献
235.
236.
Xiu-li Yan Xing Wu Jian-fei Zhou Zhi-guo Zhang Jinguo Wang 《Journal of Crystal Growth》2000,220(4):543-547
High optical quality Er3+:YVO4 laser crystals have been grown by using the floating zone method (FZ). The spectroscopic properties and 3 μm lasing of Er3+:YVO4 were investigated. It is found that the Er3+ concentration has a negative effect on the emission of the transition 4I13/2→4I15/2(1.55 μm ), and a positive effect on that of the 4I11/2→4I13/2 transition (2.68 μm). With direct upper-state pumping and a plane-concave cavity a self-terminating laser was achieved at the wavelength of 2.724 μm in the 30 at% Er3+ doped sample. 相似文献
237.
合成方法对MCM-22分子筛的结构、性质及催化性能的影响 总被引:5,自引:0,他引:5
在水热条件下分别以动态法和静态法合成了高纯度和高结晶度的MCM-22分子筛.采用N2吸附、XRD、TEM和FTIR等方法研究了制备方法对分子筛的结构及性质的影响.结果表明,动态法合成的MCM-22比静态法合成的分子筛的晶粒小,酸量低.在丙酮一步法合成甲基异丁基酮反应中,静态条件下合成的MCM-22为载体的催化剂的丙酮转化率较高,这是由于该分子筛的酸量较高所致.而MIBK的选择性则呈相反趋势,这可能与动态条件下合成的分子筛粒径小、孔道短有关. 相似文献
238.
GUO Xiong hua LI Shu ping HOU Wan guo ** HAN Shu hua HU Ji fan LI Dong qing . Key Laboratory for Colloid Interface Chemistry of State Education Ministry . Physics Microelectronics Institute Shandong University Jinan P.R. China . Department of Mechanical & Industrial Engineering University of Toronto Toronto MS G Canada 《高等学校化学研究》2003,19(2):211-215
IntroductionLayered double hydroxides( LDHs) with hy-drotalcite ( HT ) - type structure are composed oftrivalent and divalent metal ions and have the gen-eral formula[1] ,[M2 + 1-x M3 + x ( OH) 2 ]x+ An-x/ n· m H2 O,where M3 + is a trivalentmental ion,such as Al3 + ,Fe3 + ,La3 + ,Ni3 + ,Mn3 + etc.,M2 + is a divalentmetal ion,such as Mg2 + ,Zn2 + ,Ca2 + ,Cu2 + ,Co2 +etc.,An-is a charge compensating anion,such asOH-,Cl-,NO-3 ,CO2 -3 etc.,m is the number ofthe moles of co- intercalat… 相似文献
239.
240.
WU Ren-Ping YU Yan GU Ying Yun GUO Jin-Yu 《结构化学》2007,26(5):562-566
Deep color glass-ceramics is prepared by using gold tailings as the main raw material, and Cr2O3 is added as nucleation agent. Influence of different Cr2O3 additions on crystallization structure and properties of CaO-MgO-Al2O3-SiO2 glass-ceramics has been discussed so as to select optimum additions. DTA is employed to determine optimum crystallization and nucleation temperatures; XRD and SEM are used to characterize microstructure of each sample; and performance indexes, such as water absorption, bulk density, flexural strength and so on, are also determined. Experimental results show that when 3wt% Cr2O3 is introduced, fine glass-ceramics with diopside as the main crystal and Ca-Fe diopside as the second-crystal is obtained, and its corresponding performance indexes are as follows: water absorption 0.12%, bulk density 2.56 g/cm3, and flexural strength 70.01 Mpa. 相似文献