Xem 1-18 trên 18 kết quả Vibrational frequencies
  • During the years surrounding the new millennium, the field of vibrational optical activity (VOA), comprised principally of vibrational circular dichroism (VCD) and vibrational Raman optical activity (ROA), underwent a transition from a specialized area of research that had been practiced by a handful of pioneers into an important newfield of spectroscopy practiced by an increasing number of scientists worldwide. This transition was made possible by the development of commercial instrumentation and software for the routine measurement and quantum chemical calculation ofVOA.

    pdf388p hotmoingay 03-01-2013 18 4   Download

  • This book is a compilation of some selected articles devoted to the analysis and control of vibrations. Vibrations are a phenomenon found in many engineering systems; their harmful effects are translated into low performance, noise, energy misspend, discomfort and system breakdown, among others. These are the reasons why, in the last years, researchers have made great efforts in seeking ways to eliminate them totally or partially.

    pdf290p greengrass304 15-09-2012 34 15   Download

  • In the present paper the governing equations for dynamical analysis of corrugated cross-ply laminated composite plates in the form of a sin wave are developed based on the Kirchoff-Love’s theory and the extension of Seydel’s technique. The problems of natural vibration and forced vibration of a plate with various boundary conditions are studied. Effects of factors as geometry dimensions, order of laminate as well as waved-amplitude on frequency of natural vibration, amplitude of forced vibration of the corrugated cross-ply laminated composite plates are also analysed. ...

    pdf8p tuanlocmuido 19-12-2012 18 1   Download

  • This thesis aimed to apply the SEM for dynamic analysis of cracked beam subjected moving harmonic force in the frequency domain. Namely, the frequency response of a cracked beam subjected to moving harmonic force is obtained explicitly and examined in dependence upon the load and crack parameters. This task is acknowledged herein spectral analysis of cracked beam subjected to moving load.

    pdf27p change00 04-05-2016 6 1   Download

  •  Infrared (IR) Spectroscopy: – First real IR spectra measured by Abney and Festing in 1880’s – Technique made into a routine analytical method between 1903- 1940 (especially by Coblentz at the US NBS) – IR spectroscopy through most of the 20th century is done with dispersive (grating) instruments, i.e. monochromators – Fourier Transform (FT) IR instruments become common in the 1980’s, led to a great increase in sensitivity and resolution  Raman Spectroscopy: – In 1928, C. V.

    pdf31p qdung92ct 03-07-2012 50 9   Download

  • In any structure or assembly, certain whole-body motions and certain deformations are more common than others; the most likely (easiest to excite) motions will occur at certain natural frequencies. Certain exciting or forcing frequencies may coincide with the natural frequencies (resonance) and give relatively severe vibration responses. We will now discuss the much-simplified system shown in Fig.

    pdf21p liemthanh 16-12-2009 43 6   Download

  • Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Observation of the low frequency vibrational modes of bacteriophage M13 in water by Raman spectroscopy

    pdf11p dauphong7 13-01-2012 26 3   Download

  • Integrating statistics and dynamics within a single volume, the book will support the study of engineering mechanics throughout an undergraduate course. The theory of two- and three-dimensional dynamics of particles and rigid bodies, leading to Euler's equations, is developed. The vibration of one- and two-degree-of-freedom systems and an introduction to automatic control, now including frequency response methods, are covered.

    pdf96p kennybibo 14-07-2012 19 3   Download

  • A new procedure for calculation and analysis of dispersion relation and real atomic vibration of fcc crystals containing dopant atom has been developed using anharmonic effective potential. Analytical expressions for dispersion relation separated by acoustic and optical branches; forbidden zone; effective force constant; Debye frequency and temperature; amplitude and phase of real vibration of atomic chain containing dopant atom have been derived. They contain Morse potential parameters characterizing vibration of each pair of atoms. ...

    pdf8p tuanlocmuido 19-12-2012 17 2   Download

  • The first set of indicators focuses on formal accounts; the mechanics of the use of these accounts ( frequency of use, mode of access); the purpose of these accounts (personal or business, receipt of payments from work, government, or family); barriers to account use; and alternatives to formal accounts (mobile money). The account penetration indicator measures individual or joint ownership of formal accounts—accounts at a formal financial institution such as a bank, credit union, co- operative, post office, or microfinance institution.

    pdf9p mebachano 01-02-2013 8 2   Download

  • As the authors state in their introduction, family mealtimes may initially seem to be an unlikely topic for a publication that aims to present research information relevant to pending social policy. However, this paper convincingly argues that there is more than meets the eye in regard to the topic’s relevance to policy. First, Fiese and Schwartz clearly portray the importance of family mealtimes to child health and well-being. They explore frequency, climate and family food choices as aspects of the phenomenon.

    pdf15p connhobinh 10-12-2012 17 1   Download

  • 14 Active Vibration Absorption and Delayed Feedback Tuning 14.1 14.2 Nejat Olgac University of Connecticut Introduction Delayed Resonator Dynamic Absorbers The Delayed Resonator Dynamic Absorber with Acceleration Feedback • Automatic Tuning Algorithm for the Delayed Resonator Absorber • The Centrifugal Delayed Resonator Torsional Vibration Absorber Martin Hosek University of Connecticut 14.3 Multiple Frequency ATVA and Its Stability Synopsis • Stability Analysis; Directional Stability Chart Method • Optimum ATVA for Wide-Band Applications 14.

    pdf42p medinova 28-10-2010 33 11   Download

  • Due to the success of the first edition of The Engineering Handbook published in 1995 I am pleased to provide the second edition ten years later fully updated and expanded. Purpose The purpose of The Engineering Handbook, Second Edition is to provide in a single volume a ready reference for the practicing engineer in industry, government, and academia. The book in its comprehensive format is divided into 30 sections which encompass the field of engineering and includes 19 brand new chapters and 131 fully updated contributions.

    pdf0p thix1minh 16-10-2012 48 11   Download

  • Tham khảo sách 'the engineering the handbook - second edition ii (end)', khoa học tự nhiên, hoá học phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả

    pdf0p thix1minh 16-10-2012 26 11   Download

  • NOISE AND DISTORTION 2.1 Introduction 2.2 White Noise 2.3 Coloured Noise 2.4 Impulsive Noise 2.5 Transient Noise Pulses 2.6 2.7 2.8 2.9 2.10 Thermal Noise Shot Noise Electromagnetic Noise Channel Distortions Modelling Noise N oise can be defined as an unwanted signal that interferes with the communication or measurement of another signal. A noise itself is a signal that conveys information regarding the source of the noise. For example, the noise from a car engine conveys information regarding the state of the engine.

    pdf15p khinhkha 30-07-2010 64 8   Download

  • Acoustics is a discipline that deals with many types of fields wave phenomena. Originally the field of Acoustics was consecrated to the sound, that is, the study of small pressure waves in air detected by the human ear. The scope of this field of physics has been extended to higher and lower frequencies and to higher intensity levels. Moreover, structural vibrations are also included in acoustics as a wave phenomena produced by elastic waves. This book is focused on acoustic waves in fluid media and elastic perturbations in heterogeneous media....

    pdf0p ktcn_1 10-07-2012 31 7   Download

  • CHAPTER 23 VIBRATION AND SHOCK Wayne T\istin Equipment Reliability Institute Santa Barbara, California 23.1 23.2 23.3 23.4 VIBRATION ROTATIONAL IMBALANCE VIBRATION MEASUREMENT ACCELERATION MEASUREMENT 661 23.5 SHOCK MEASUREMENT AND ANALYSIS 23.6 SHOCKTESTING SHAKE TESTS FOR ELECTRONIC ASSEMBLIES 692 695 705 668 673 23.7 681 23.1 VIBRATION In any structure or assembly, certain whole-body motions and certain deformations are more common than others; the most likely (easiest to excite) motions will occur at certain natural frequencies.

    pdf21p hadalabo 29-09-2010 26 4   Download

  • The ultrasonic transducer behaves as a ‘speaker’ in send mode (from 40 to 50 kHz). The electronics of the ultrasonic transducer produces electrical pulses to set the piezoceramic element in motion (conversion of electrical energy to mechanical energy). The piezoceramic element is located on the inside of the outer diaphragm. The outer diaphragm vibrates in line with the resonance frequency and produces ultrasonic waves. The short pulse sequences hit an obstacle and are bounced back (reflected).

    pdf12p nhacnenzingme 23-03-2013 13 3   Download

Đồng bộ tài khoản