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Sample records for attached vibrational probe

  1. Probing zeolites by vibrational spectroscopies.

    Science.gov (United States)

    Bordiga, Silvia; Lamberti, Carlo; Bonino, Francesca; Travert, Arnaud; Thibault-Starzyk, Frédéric

    2015-10-21

    This review addresses the most relevant aspects of vibrational spectroscopies (IR, Raman and INS) applied to zeolites and zeotype materials. Surface Brønsted and Lewis acidity and surface basicity are treated in detail. The role of probe molecules and the relevance of tuning both the proton affinity and the steric hindrance of the probe to fully understand and map the complex site population present inside microporous materials are critically discussed. A detailed description of the methods needed to precisely determine the IR absorption coefficients is given, making IR a quantitative technique. The thermodynamic parameters of the adsorption process that can be extracted from a variable-temperature IR study are described. Finally, cutting-edge space- and time-resolved experiments are reviewed. All aspects are discussed by reporting relevant examples. When available, the theoretical literature related to the reviewed experimental results is reported to support the interpretation of the vibrational spectra on an atomic level.

  2. Comparative evaluation of probing depth and clinical attachment level using a manual probe and Florida probe

    OpenAIRE

    Amandeep Kour; Ashish Kumar; Komal Puri; Manish Khatri; Mansi Bansal; Geeti Gupta

    2016-01-01

    Background: To compare and evaluate the intra- and inter-examiner efficacy and reproducibility of the first-generation manual (Williams) probe and the third-generation Florida probe in terms of measuring pocket probing depth (PD) and clinical attachment level (CAL). Materials and Methods: Forty subjects/4000 sites were included in this comparative, cross-sectional study. Group- and site-wise categorizations were done. Based on gingival index, PD, and CAL, patients were divided into four group...

  3. Comparative evaluation of probing depth and clinical attachment level using a manual probe and Florida probe

    Directory of Open Access Journals (Sweden)

    Amandeep Kour

    2016-01-01

    Full Text Available Background: To compare and evaluate the intra- and inter-examiner efficacy and reproducibility of the first-generation manual (Williams probe and the third-generation Florida probe in terms of measuring pocket probing depth (PD and clinical attachment level (CAL. Materials and Methods: Forty subjects/4000 sites were included in this comparative, cross-sectional study. Group- and site-wise categorizations were done. Based on gingival index, PD, and CAL, patients were divided into four groups, i.e., periodontally healthy, gingivitis, mild to moderate periodontitis, and severe periodontitis. Further, based on these parameters, a total of 4000 sites, with 1000 sites in each category randomly selected from these 40 patients, were taken. Full mouth PD and CAL measurements were recorded with two probes, by Examiner 1 and on Ramfjord teeth by Examiner 2. Results: Full mouth and Ramfjord teeth group- and site-wise PD obtained with the manual probe by both the examiners were statistically significantly deeper than that obtained with the Florida probe. The full mouth and Ramfjord teeth mean CAL measurement by Florida probe was higher as compared to manual probe in mild to moderate periodontitis group and sites, whereas in severe periodontitis group and sites, manual probe recorded higher CAL as compared to Florida probe. Conclusion: Mean PD and CAL measurements were deeper with the manual probe as compared to the Florida probe in all the groups and sites, except for the mild-moderate periodontitis group and sites where the CAL measurements with the manual probe were less than the Florida probe. Manual probe was more reproducible and showed less interexaminer variability as compared to the Florida probe.

  4. Dissociative electron attachment and vibrational excitation of CF{sub 3}Cl: Effect of two vibrational modes revisited

    Energy Technology Data Exchange (ETDEWEB)

    Tarana, Michal [Department of Physics and Astronomy, University of Nebraska, Lincoln, Nebraska 68588 (United States); JILA, University of Colorado and NIST, Boulder, Colorado 80309-0440 (United States); Houfek, Karel; Horacek, Jiri [Institute of Theoretical Physics, Faculty of Mathematics and Physics, Charles University in Prague, V Holesovickach 2, Prague (Czech Republic); Fabrikant, Ilya I. [Department of Physics and Astronomy, University of Nebraska, Lincoln, Nebraska 68588 (United States); Department of Physics and Astronomy, Open University, Walton Hall, Milton Keynes MK7 6AA (United Kingdom)

    2011-11-15

    We present a study of dissociative electron attachment and vibrational excitation processes in electron collisions with the CF{sub 3}Cl molecule. The calculations are based on the two-dimensional nuclear dynamics including the C-Cl symmetric stretch coordinate and the CF{sub 3} symmetric deformation (umbrella) coordinate. The complex potential energy surfaces are calculated using the ab initio R-matrix method. The results for dissociative attachment and vibrational excitation of the umbrella mode agree quite well with experiment whereas the cross section for excitation of the C-Cl symmetric stretch vibrations is about a factor-of-three too low in comparison with experimental data.

  5. Mapping electric currents around skeletal muscle with a vibrating probe

    OpenAIRE

    1984-01-01

    A vibrating microelectrode, or vibrating probe (Jaffe and Nuccitelli, 1974), was used to map the pattern of artificially created electric currents flowing around single muscle fibers at the edge of frog cutaneous pectoris muscles. When a muscle fiber was impaled with a micropipette, a "point sink" of current was often created at the site of impalement because of injury to the cell membrane. Current, being drawn from the flanking membrane, flowed into the cell only at this point. This defined ...

  6. Phosphate vibrations probe local electric fields and hydration in biomolecules

    OpenAIRE

    Nicholas M Levinson; Bolte, Erin E.; Miller, Carrie S.; Corcelli, Steven A.; Boxer, Steven G.

    2011-01-01

    The role of electric fields in important biological processes like binding and catalysis has been studied almost exclusively by computational methods. Experimental measurements of the local electric field in macromolecules are possible using suitably calibrated vibrational probes. Here we demonstrate that the vibrational transitions of phosphate groups are highly sensitive to an electric field and quantify that sensitivity, allowing local electric field measurements to be made in phosphate-co...

  7. Phosphate vibrations probe local electric fields and hydration in biomolecules

    Science.gov (United States)

    Levinson, Nicholas M.; Bolte, Erin E.; Miller, Carrie S.

    2011-01-01

    The role of electric fields in important biological processes like binding and catalysis has been studied almost exclusively by computational methods. Experimental measurements of the local electric field in macromolecules are possible using suitably calibrated vibrational probes. Here we demonstrate that the vibrational transitions of phosphate groups are highly sensitive to an electric field and quantify that sensitivity, allowing local electric field measurements to be made in phosphate-containing biological systems without chemical modification. PMID:21809829

  8. Vibration Damping Via Acoustic Treatment Attached To Vehicle Body Panels

    Science.gov (United States)

    Gambino, Carlo

    Currently, in the automotive industry, the control of noise and vibration is the subject of much research, oriented towards the creation of innovative solutions to improve the comfort of the vehicle and to reduce its cost and weight. This thesis fits into this particular framework, as it aims to investigate the possibility of integrating the functions of sound absorptioninsulation and vibration damping in a unique component. At present the bituminous viscoelastic treatments, which are bonded to the car body panels, take charge of the vibration damping, while the sound absorption and insulation is obtained by means of the poroacoustic treatments. The solution proposed here consists of employing porous materials to perform both these functions, thus allowing the partial or complete removal of the viscoelastic damping treatments from the car body. This should decrease the weight of the vehicle, reducing fuel consumption and emissions, and it might also benefit production costs.

  9. Equilibria and vibration of a buckled beam with attached masses or spring-mass systems

    Science.gov (United States)

    Plaut, Raymond H.; Virgin, Lawrence N.

    2016-09-01

    A buckled beam with immovable pinned ends is considered. Attached to the beam are either one concentrated mass, two concentrated masses, a spring-mass system (that could model a human, robot, or passive vibration absorber), or a horizontal rigid bar with two vertical end springs (a "bounce-pitch" system that could model an animal or a vehicle). In the theoretical analysis, the beam is modeled as an inextensible elastica. Equilibrium configurations are determined first. Then small free vibrations about equilibrium are examined, and the lowest frequencies and corresponding modes are computed. The effects of various parameters are investigated, such as the ratio of the span to the total arc length of the beam, the locations and weights of the attached masses and systems, and the stiffnesses of the springs. For the case of a single attached mass, experiments are conducted and the results are compared to the theoretical ones.

  10. Study of a vibrating fiber probing system for 3-D micro-structures: performance improvement

    Science.gov (United States)

    Murakami, H.; Katsuki, A.; Sajima, T.; Suematsu, T.

    2014-09-01

    This paper presents a system for measuring 3D micro-structures that uses an optical fiber probe equipped with a piezo element that causes the probe to vibrate. The optical fiber probe consists of a stylus shaft with a diameter of 3 µm and a glass ball with a diameter of 5 µm attached to the tip. The stylus is vibrated in a circular motion in a single plane. The vibrator mechanism is introduced to prevent adhesion of the stylus tip to the surface being measured. This adhesion, which adversely affects the accuracy and time of the measurement, is caused by intermolecular, electrostatic, and liquid bridge forces. The measuring principle involves monitoring the vibrational amplitude of the stylus shaft that is required to prevent the adhesion of the stylus tip to the surface being measured, this amplitude being measured optically. In our previous report (Murakami et al 2012 Key Eng. Mater. 523-524 907-12), we found that the stylus shaft actually moves in an elliptical motion when it is set to describe a circular motion in the X-Y plane. Therefore, when a measurement is taken, it is necessary to adjust the motion of the piezoelectric tube to compensate for the difference between the diameter of the perfect circle and the actual elliptical motion of the stylus shaft displacement. In this study, the stylus characteristics were examined and the motion of the stylus shaft was then corrected to attain the desired circular motion. Next, the expansion of the measuring area by using a line laser was investigated. Finally, an experiment involving the measurement of a micro-hole was performed to demonstrate the practicality of the vibrating fiber probe. As a result, it was shown that the displacement between the diameter of the perfect circle and the actual elliptical motion of the stylus tip was about 0.034 µm after compensation. In addition, it was confirmed that the measurement area can be expanded by using an optical slit, but the standard deviation of the

  11. Rate coefficients for dissociative attachment and resonant electron-impact dissociation involving vibrationally excited O{sub 2} molecules

    Energy Technology Data Exchange (ETDEWEB)

    Laporta, V. [Istituto di Metodologie Inorganiche e dei Plasmi, CNR, Bari, Italy and Department of Physics and Astronomy, University College London, London WC1E 6BT (United Kingdom); Celiberto, R. [Dipartimento di Ingegneria Civile, Ambientale, del Territorio, Edile e di Chimica, Politecnico di Bari, Italy and Istituto di Metodologie Inorganiche e dei Plasmi, CNR, Bari (Italy); Tennyson, J. [Department of Physics and Astronomy, University College London, London WC1E 6BT (United Kingdom)

    2014-12-09

    Rate coefficients for dissociative electron attachment and electron-impact dissociation processes, involving vibrationally excited molecular oxygen, are presented. Analytical fits of the calculated numerical data, useful in the applications, are also provided.

  12. Modeling and experimental vibration analysis of nanomechanical cantilever active probes

    International Nuclear Information System (INIS)

    Nanomechanical cantilever (NMC) active probes have recently received increased attention in a variety of nanoscale sensing and measurement applications. Current modeling practices call for a uniform cantilever beam without considering the intentional jump discontinuities associated with the piezoelectric layer attachment and the NMC cross-sectional step. This paper presents a comprehensive modeling framework for modal characterization and dynamic response analysis of NMC active probes with geometrical discontinuities. The entire length of the NMC is divided into three segments of uniform beams followed by applying appropriate continuity conditions. The characteristics matrix equation is then used to solve for system natural frequencies and mode shapes. Using an equivalent electromechanical moment of a piezoelectric layer, forced motion analysis of the system is carried out. An experimental setup consisting of a commercial NMC active probe from Veeco and a state-of-the-art microsystem analyzer, the MSA-400 from Polytec, is developed to verify the theoretical developments proposed here. Using a parameter estimation technique based on minimizing the modeling error, optimal values of system parameters are identified. Mode shapes and the modal frequency response of the system for the first three modes determined from the proposed model are compared with those obtained from the experiment and commonly used theory for uniform beams. Results indicate that the uniform beam model fails to accurately predict the actual system response, especially in multiple-mode operation, while the proposed discontinuous beam model demonstrates good agreement with the experimental data. Such detailed and accurate modeling framework can lead to significant enhancement in the sensitivity of piezoelectric-based NMC sensors for use in variety of sensing and imaging applications

  13. Dissociative electron attachment and electron-impact resonant dissociation of vibrationally excited O2 molecules

    CERN Document Server

    Laporta, V; Tennyson, J

    2015-01-01

    State-by-state cross sections for dissociative electron attachment and electron-impact dissociation for molecular oxygen are computed using ab initio resonance curves calculated with the R-matrix method. When O2 is in its vibrational ground state, the main contribution for both processes comes from the $^2\\Pi_u$ resonance state of $O_2^-$ but with a significant contribution from the $^4\\Sigma$ resonant state. Vibrational excitation leads to an increased contribution from the low-lying $^2\\Pi_{g}$ resonance, greatly increased cross sections for both processes, and the threshold moving to lower energies. These results provide important input for models of O2-containing plasmas in nonequilibrium conditions.

  14. A Nonlocal Model of Dissociative Electron Attachment andVibrational Excitation of NO

    Energy Technology Data Exchange (ETDEWEB)

    Trevisan, Cynthia S.; Houfek, Karel; Zhang, Z.; Orel, Ann E.; McCurdy, C. William; Rescigno, Thomas N.

    2005-01-01

    We present the results of a study of elastic scattering and vibrational excitation of NO by electron impact in the low-energy (0-2eV) region where the cross sections are dominated by resonance contributions. The {sup 3}{Sigma}{sup -}, {sup 1}{Delta} and {sup 1}{Sigma}{sup +} NO{sup -} resonance lifetimes are taken from our earlier study [Phys. Rev. A 69, 062711(2004)], but the resonance energies used here are obtained from new configuration-interaction studies. Here we employ a more elaborate nonlocal treatment of the nuclear dynamics, which is found to remedy the principal deficiencies of the local complex potential model we employed in our earlier study, and gives cross sections in better agreement with the most recent experiments. We also present cross sections for dissociative electron attachment to NO leading to ground state products, O{sup -}({sup 2}P) + N({sup 4}S). The calculations show that, while the peak cross sections starting from NO in its ground vibrational state are very small ({approx} 10{sup -20}cm{sup 2}), the cross sections are extremely sensitive to vibrational excitation of the target and should be readily observable for target NO molecules excited to {nu} = 10 and above.

  15. A nonlocal, ab initio model of dissociative electron attachment and vibrational excitation of NO

    Energy Technology Data Exchange (ETDEWEB)

    Trevisan, Cynthia S.; Houfek, Karel; Zhang, Zhiyong; Orel, Ann E.; McCurdy, C. William; Rescigno, Thomas N.

    2005-02-01

    We present the results of an ab initio study of elastic scattering and vibrational excitation of NO by electron impact in the low-energy (0-2 eV) region where the cross sections are dominated by resonance contributions. The 3Sigma-, 1Delta and 1Sigma+ NO- resonance lifetimes are taken from our earlier study [Phys. Rev. A 69, 062711 (2004)], but the resonance energies used here are obtained from new configuration-interaction studies. Here we employ a more elaborate nonlocal treatment of the nuclear dynamics, which is found to remedy the principal deficiencies of the local complex potential model we employed in our earlier study, and gives cross sections in better agreement with the most recent experiments. We also present cross sections for dissociative electron attachment to NO leading to groundstate products. The calculations show that, while the peak cross sections starting from NO in its ground vibrational state are very small, the cross sections are extremely sensitive to vibrational excitation of the target and should be readily observable for target NO molecules excited to v = 10 and above.

  16. Vibrational dynamics of aqueous hydroxide solutions probed using broadband 2DIR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Mandal, Aritra [Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, University of Chicago, Chicago, Illinois 60637 (United States); Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Tokmakoff, Andrei, E-mail: tokmakoff@uchicago.edu [Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, University of Chicago, Chicago, Illinois 60637 (United States)

    2015-11-21

    We employed ultrafast transient absorption and broadband 2DIR spectroscopy to study the vibrational dynamics of aqueous hydroxide solutions by exciting the O–H stretch vibrations of the strongly hydrogen-bonded hydroxide solvation shell water and probing the continuum absorption of the solvated ion between 1500 and 3800 cm{sup −1}. We observe rapid vibrational relaxation processes on 150–250 fs time scales across the entire probed spectral region as well as slower vibrational dynamics on 1–2 ps time scales. Furthermore, the O–H stretch excitation loses its frequency memory in 180 fs, and vibrational energy exchange between bulk-like water vibrations and hydroxide-associated water vibrations occurs in ∼200 fs. The fast dynamics in this system originate in strong nonlinear coupling between intra- and intermolecular vibrations and are explained in terms of non-adiabatic vibrational relaxation. These measurements indicate that the vibrational dynamics of the aqueous hydroxide complex are faster than the time scales reported for long-range transport of protons in aqueous hydroxide solutions.

  17. Vibrational dynamics of aqueous hydroxide solutions probed using broadband 2DIR spectroscopy

    International Nuclear Information System (INIS)

    We employed ultrafast transient absorption and broadband 2DIR spectroscopy to study the vibrational dynamics of aqueous hydroxide solutions by exciting the O–H stretch vibrations of the strongly hydrogen-bonded hydroxide solvation shell water and probing the continuum absorption of the solvated ion between 1500 and 3800 cm−1. We observe rapid vibrational relaxation processes on 150–250 fs time scales across the entire probed spectral region as well as slower vibrational dynamics on 1–2 ps time scales. Furthermore, the O–H stretch excitation loses its frequency memory in 180 fs, and vibrational energy exchange between bulk-like water vibrations and hydroxide-associated water vibrations occurs in ∼200 fs. The fast dynamics in this system originate in strong nonlinear coupling between intra- and intermolecular vibrations and are explained in terms of non-adiabatic vibrational relaxation. These measurements indicate that the vibrational dynamics of the aqueous hydroxide complex are faster than the time scales reported for long-range transport of protons in aqueous hydroxide solutions

  18. Probing and extracting the structure of vibrating SF6 molecules with inner-shell photoelectrons

    Science.gov (United States)

    Nguyen, Ngoc-Ty; Lucchese, R. R.; Lin, C. D.; Le, Anh-Thu

    2016-06-01

    We propose a scheme for probing the structure of vibrating molecules with photoelectrons generated from ultrashort soft-x-ray pulses. As an example we analyze below-100-eV photoelectrons liberated from the S (2 p ) orbital of vibrating SF6 molecules to image very small structural changes of molecular vibration. In particular, photoionization cross sections and photoelectron angular distributions (PAD) at nonequilibrium geometries can be retrieved accurately with photoelectrons near the shape resonance at 13 eV. This is achieved with a pump-probe scheme, in which the symmetric stretch mode is first Raman excited predominantly by a relatively short laser pulse and then later probed at different time delays by a few-femtosecond soft-x-ray pulse with photon energy near 200 eV.

  19. Spectroscopic probes of vibrationally excited molecules at chemically significant energies

    Energy Technology Data Exchange (ETDEWEB)

    Rizzo, T.R. [Univ. of Rochester, NY (United States)

    1993-12-01

    This project involves the application of multiple-resonance spectroscopic techniques for investigating energy transfer and dissociation dynamics of highly vibrationally excited molecules. Two major goals of this work are: (1) to provide information on potential energy surfaces of combustion related molecules at chemically significant energies, and (2) to test theoretical modes of unimolecular dissociation rates critically via quantum-state resolved measurements.

  20. Vibrational excitations in molecular layers probed by ballistic electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Kajen, Rasanayagam Sivasayan; Chandrasekhar, Natarajan [Institute of Materials Research and Engineering, 3 Research Link, 117602 (Singapore); Feng Xinliang; Muellen, Klaus [Max-Planck-Institut fuer Polymerforschung, Postfach 3148, D-55021 Mainz (Germany); Su Haibin, E-mail: n-chandra@imre.a-star.edu.sg, E-mail: muellen@mpip-mainz.mpg.de, E-mail: hbsu@ntu.edu.sg [Division of Materials Science, Nanyang Technological University, 50 Nanyang Avenue, 639798 (Singapore)

    2011-10-28

    We demonstrate the information on molecular vibrational modes via the second derivative (d{sup 2}I{sub B}/dV{sup 2}) of the ballistic electron emission spectroscopy (BEES) current. The proposed method does not create huge fields as in the case of conventional derivative spectroscopy and maintains a zero bias across the device. BEES studies carried out on three different types of large polycyclic aromatic hydrocarbon (PAH) molecular layers show that the d{sup 2}I{sub B}/dV{sup 2} spectra consist of uniformly spaced peaks corresponding to vibronic excitations. The peak spacing is found to be identical for molecules within the same PAH family though the BEES onset voltage varies for different molecules. In addition, injection into a particular orbital appears to correspond to a specific vibrational mode as the manifestation of the symmetry principle.

  1. Cable vibration control with both lateral and rotational dampers attached at an intermediate location

    Science.gov (United States)

    Chen, Lin; Sun, Limin; Nagarajaiah, Satish

    2016-09-01

    Lateral dampers have been extensively studied and implemented for supplementing modal damping in cable vibration mitigation. When considering the cable flexural stiffness that is actually present, albeit small, there is another degree of freedom of the cable at the lateral damper, namely the rotation, that can be constrained by a rotational damper to achieve larger additional damping. This is of particular significance for long cables where the near-anchorage lateral damper alone is usually insufficient. The problem of a cable with bending stiffness, attached with both lateral and rotational dampers at an intermediate point, is therefore considered in this study. The characteristic equation of the resulting system is formulated by assembling the dynamic stiffness from the two segments divided by the damper, which is subsequently solved using argument principle method. Dynamics of the controlled system is thus discussed in general through parametric analysis. For the case where the damper location is close to the anchorage, asymptotic solutions for complex frequency and damping ratio are provided; explicit formulas for determining the optimal damper coefficients are also derived. It is found that when the lateral and rotational damper coefficients are properly balanced, the proposed strategy can achieve up to 30 percent damping enhancement compared to the case with only the lateral damper, in practical cable bending stiffness range.

  2. Double resonant absorption measurement of acetylene symmetric vibrational states probed with cavity ring down spectroscopy

    CERN Document Server

    Karhu, J; Vainio, M; Metsälä, M; Hoekstra, S; Halonen, L

    2016-01-01

    A novel mid-infrared/near-infrared double resonant absorption setup for studying infrared-inactive vibrational states is presented. A strong vibrational transition in the mid-infrared region is excited using an idler beam from a singly resonant continuous-wave optical parametric oscillator, to populate an intermediate vibrational state. High output power of the optical parametric oscillator and the strength of the mid-infrared transition result in efficient population transfer to the intermediate state, which allows measuring secondary transitions from this state with a high signal-to-noise ratio. A secondary, near-infrared transition from the intermediate state is probed using cavity ring down spectroscopy, which provides high sensitivity in this wavelength region. Due to the narrow linewidths of the excitation sources, the rovibrational lines of the secondary transition are measured with sub-Doppler resolution. The setup is used to access a previously unreported symmetric vibrational state of acetylene, $\

  3. Attachments

    International Nuclear Information System (INIS)

    In this attachment to the Annual report 1999 of the Nuclear Regulatory Authority of the Slovak Republic (UJD) the economic and personnel data of the UJD, used abbreviations, as well as the International nuclear event scales - INES are presented. Professional level of staff of the UJD is influenced by the education structure of its staff, when nearly 75% of the total number of staff has a university degree. A of 31.12.1999 there were 79 employees as average calculated number. Financing of the regulator in 1999 was mainly provided from the state budget, which represented 96% of all expenditures. The total volume of expenditures for UJD activity funded from the state budget achieved as of 31.12.1999 Slovak crowns (SK) 67 067 thousands. In the main category of expenditures an amount of SK 63 499 thous. was used for current activities, and the difference of SK 3 587 thous. was used for raising capital assets. Significant increase expenditures in the evaluated year compared to the 1998 was caused by a special purpose payment made by the Slovakia into the Fund for reconstruction of the Chernobyl cover (SK 19 996 thous.) funded through the budget chapter of the regulator. In the structure of current expenditures the highest share is taken by current transfers to abroad in total of SK 22 543 thous., i.e. contribution to reconstruction of Chernobyl cover made to the EBRD and contributions to the Fund of Technical Co-operation of the IAEA. For procurement of goods and services an amount of SK 19 814 thous. was spent, of which SK 7 054 thous. was used for funding science and technology tasks which were contracted out. The decision-making process in performing state supervision forced UJD to contact out various expert opinions and studies, for which UJD paid SK 2 058 thous. in total. Other expenditures in a volume of SK 10 702 thous. represent travel expenses, goods and services for UJD, rent for offices and other inevitable expenses. Salaries of staff represented SK 15 953

  4. Power enhancing by reversing mode sequence in tuned mass-spring unit attached vibration energy harvester

    Directory of Open Access Journals (Sweden)

    Jae Eun Kim

    2013-07-01

    Full Text Available We propose a vibration energy harvester consisting of an auxiliary frequency-tuned mass unit and a piezoelectric vibration energy harvesting unit for enhancing output power. The proposed integrated system is so configured that its out-of-phase mode can appear at the lowest eigenfrequency unlike in the conventional system using a tuned unit. Such an arrangement makes the resulting system distinctive: enhanced output power at or near the target operating frequency and very little eigenfrequency separation, not observed in conventional eigenfrequency-tuned vibration energy harvesters. The power enhancement of the proposed system is theoretically examined with and without tip mass normalization or footprint area normalization.

  5. A framework for the analysis of vibrations of structures with uncertain attachments

    Science.gov (United States)

    Li, Shuo; Mace, Brian R.; Ferguson, Neil S.; Halkyard, Roger

    2016-09-01

    Attachments affect the dynamic response of an assembled structure. When engineers are modelling structures, small attachments will often not be included in the “bare” model, especially in the initial design stages. The location of these attachments might be poorly known, yet they affect the response of the structure. This paper considers how attachments jointed to the structure at uncertain points, can be included in the dynamic model of a structure. Two approaches are proposed. In the time domain, a combination of component mode synthesis, characteristic constraint modes and modal analysis gives a computationally efficient basis for subsequent analysis using, for example, Monte Carlo simulation. The frequency domain approach is based on assembly of frequency response functions of bare structure and attachment. Numerical examples of a beam and a plate with a point mass added at an uncertain location are considered and predictions compared with experiment results.

  6. Double resonant absorption measurement of acetylene symmetric vibrational states probed with cavity ring down spectroscopy

    Science.gov (United States)

    Karhu, J.; Nauta, J.; Vainio, M.; Metsälä, M.; Hoekstra, S.; Halonen, L.

    2016-06-01

    A novel mid-infrared/near-infrared double resonant absorption setup for studying infrared-inactive vibrational states is presented. A strong vibrational transition in the mid-infrared region is excited using an idler beam from a singly resonant continuous-wave optical parametric oscillator, to populate an intermediate vibrational state. High output power of the optical parametric oscillator and the strength of the mid-infrared transition result in efficient population transfer to the intermediate state, which allows measuring secondary transitions from this state with a high signal-to-noise ratio. A secondary, near-infrared transition from the intermediate state is probed using cavity ring-down spectroscopy, which provides high sensitivity in this wavelength region. Due to the narrow linewidths of the excitation sources, the rovibrational lines of the secondary transition are measured with sub-Doppler resolution. The setup is used to access a previously unreported symmetric vibrational state of acetylene, ν 1 + ν 2 + ν 3 + ν4 1 + ν5 - 1 in the normal mode notation. Single-photon transitions to this state from the vibrational ground state are forbidden. Ten lines of the newly measured state are observed and fitted with the linear least-squares method to extract the band parameters. The vibrational term value was measured to be at 9775.0018(45) cm-1, the rotational parameter B was 1.162 222(37) cm-1, and the quartic centrifugal distortion parameter D was 3.998(62) × 10-6 cm-1, where the numbers in the parenthesis are one-standard errors in the least significant digits.

  7. A novel universal real-time PCR system using the attached universal duplex probes for quantitative analysis of nucleic acids

    Directory of Open Access Journals (Sweden)

    Wilson Zoe A

    2008-06-01

    Full Text Available Abstract Background Real-time PCR techniques are being widely used for nucleic acids analysis, but one limitation of current frequently employed real-time PCR is the high cost of the labeled probe for each target molecule. Results We describe a real-time PCR technique employing attached universal duplex probes (AUDP, which has the advantage of generating fluorescence by probe hydrolysis and strand displacement over current real-time PCR methods. AUDP involves one set of universal duplex probes in which the 5' end of the fluorescent probe (FP and a complementary quenching probe (QP lie in close proximity so that fluorescence can be quenched. The PCR primer pair with attached universal template (UT and the FP are identical to the UT sequence. We have shown that the AUDP technique can be used for detecting multiple target DNA sequences in both simplex and duplex real-time PCR assays for gene expression analysis, genotype identification, and genetically modified organism (GMO quantification with comparable sensitivity, reproducibility, and repeatability with other real-time PCR methods. Conclusion The results from GMO quantification, gene expression analysis, genotype identification, and GMO quantification using AUDP real-time PCR assays indicate that the AUDP real-time PCR technique has been successfully applied in nucleic acids analysis, and the developed AUDP real-time PCR technique will offer an alternative way for nucleic acid analysis with high efficiency, reliability, and flexibility at low cost.

  8. Transient Conformational Changes of Sensory Rhodopsin II Investigated by Vibrational Stark Effect Probes.

    Science.gov (United States)

    Mohrmann, Hendrik; Kube, Ines; Lórenz-Fonfría, Víctor A; Engelhard, Martin; Heberle, Joachim

    2016-05-19

    Sensory rhodopsin II (SRII) is the primary light sensor in the photophobic reaction of the halobacterium Natronomonas pharaonis. Photoactivation of SRII results in a movement of helices F and G of this seven-helical transmembrane protein. This conformational change is conveyed to the transducer protein (HtrII). Global changes in the protein backbone have been monitored by IR difference spectroscopy by recording frequency shifts in the amide bands. Here we investigate local structural changes by judiciously inserting thiocyanides at different locations of SRII. These vibrational Stark probes absorb in a frequency range devoid of any protein vibrations and respond to local changes in the dielectric, electrostatics, and hydrogen bonding. As a proof of principle, we demonstrate the use of Stark probes to test the conformational changes occurring in SRII 12 ms after photoexcitation and later. Thus, a methodology is provided to trace local conformational changes in membrane proteins by a minimal invasive probe at the high temporal resolution inherent to IR spectroscopy. PMID:27111635

  9. Free vibration analysis of elastically supported Timoshenko columns with attached masses by transfer matrix and finite element methods

    Indian Academy of Sciences (India)

    Oktay Demirdaǧ

    2008-02-01

    This paper deals with the free vibration of Timoshenko columns with attached masses having rotary inertia. The support of the model is elastically restrained against rotation. The concept of fixity factor is used to define the stiffness of the elastic connection relative to that of the column. The governing equation of the column elements is solved by applying the separation of variables method in the transfer matrix method (TMM) algorithm. The same problems are solved, also, by finite element method (FEM) algorithm in which the matrices in equation of motion are obtained for Timoshenko column, and the results are compared with the ones of TMM. The comparison graphs are presented in numerical analysis to show the effectiveness of the considered methods, and it is resulted that FEM gives closer results to TMM.

  10. Live-Cell Bioorthogonal Chemical Imaging: Stimulated Raman Scattering Microscopy of Vibrational Probes.

    Science.gov (United States)

    Wei, Lu; Hu, Fanghao; Chen, Zhixing; Shen, Yihui; Zhang, Luyuan; Min, Wei

    2016-08-16

    Innovations in light microscopy have tremendously revolutionized the way researchers study biological systems with subcellular resolution. In particular, fluorescence microscopy with the expanding choices of fluorescent probes has provided a comprehensive toolkit to tag and visualize various molecules of interest with exquisite specificity and high sensitivity. Although fluorescence microscopy is currently the method of choice for cellular imaging, it faces fundamental limitations for studying the vast number of small biomolecules. This is because common fluorescent labels, which are relatively bulky, could introduce considerable perturbation to or even completely alter the native functions of vital small biomolecules. Hence, despite their immense functional importance, these small biomolecules remain largely undetectable by fluorescence microscopy. To address this challenge, a bioorthogonal chemical imaging platform has recently been introduced. By coupling stimulated Raman scattering (SRS) microscopy, an emerging nonlinear Raman microscopy technique, with tiny and Raman-active vibrational probes (e.g., alkynes and stable isotopes), bioorthogonal chemical imaging exhibits superb sensitivity, specificity, and biocompatibility for imaging small biomolecules in live systems. In this Account, we review recent technical achievements for visualizing a broad spectrum of small biomolecules, including ribonucleosides and deoxyribonucleosides, amino acids, fatty acids, choline, glucose, cholesterol, and small-molecule drugs in live biological systems ranging from individual cells to animal tissues and model organisms. Importantly, this platform is compatible with live-cell biology, thus allowing real-time imaging of small-molecule dynamics. Moreover, we discuss further chemical and spectroscopic strategies for multicolor bioorthogonal chemical imaging, a valuable technique in the era of "omics". As a unique tool for biological discovery, this platform has been applied to

  11. Exact free vibration of multi-step Timoshenko beam system with several attachments

    Science.gov (United States)

    Farghaly, S. H.; El-Sayed, T. A.

    2016-05-01

    This paper deals with the analysis of the natural frequencies, mode shapes of an axially loaded multi-step Timoshenko beam combined system carrying several attachments. The influence of system design and the proposed sub-system non-dimensional parameters on the combined system characteristics are the major part of this investigation. The effect of material properties, rotary inertia and shear deformation of the beam system for each span are included. The end masses are elastically supported against rotation and translation at an offset point from the point of attachment. A sub-system having two degrees of freedom is located at the beam ends and at any of the intermediate stations and acts as a support and/or a suspension. The boundary conditions of the ordinary differential equation governing the lateral deflections and slope due to bending of the beam system including the shear force term, due to the sub-system, have been formulated. Exact global coefficient matrices for the combined modal frequencies, the modal shape and for the discrete sub-system have been derived. Based on these formulae, detailed parametric studies of the combined system are carried out. The applied mathematical model is valid for wide range of applications especially in mechanical, naval and structural engineering fields.

  12. Probing Bogoliubov Quasiparticles in Superfluid ^3He with a `Vibrating-Wire Like' MEMS Device

    Science.gov (United States)

    Defoort, M.; Dufresnes, S.; Ahlstrom, S. L.; Bradley, D. I.; Haley, R. P.; Guénault, A. M.; Guise, E. A.; Pickett, G. R.; Poole, M.; Woods, A. J.; Tsepelin, V.; Fisher, S. N.; Godfrin, H.; Collin, E.

    2016-05-01

    We have measured the interaction between superfluid ^3He-B and a micro-machined goalpost-shaped device at temperatures below 0.2 T_c. The measured damping follows well the theory developed for vibrating wires, in which the Andreev reflection of quasiparticles in the flow field around the moving structure leads to a nonlinear frictional force. At low velocities, the damping force is proportional to velocity, while it tends to saturate for larger excitations. Above a velocity of 2.6 mm s^{-1}, the damping abruptly increases, which is interpreted in terms of Cooper-pair breaking. Interestingly, this critical velocity is significantly lower than that reported with other mechanical probes immersed in superfluid ^3He. Furthermore, we report on a nonlinear resonance shape for large motion amplitudes that we interpret as an inertial effect due to quasiparticle friction, but other mechanisms could possibly be invoked as well.

  13. A new aromatic probe - The ring stretching vibration Raman spectroscopy frequency

    Science.gov (United States)

    Guo, Yan-bo; Liu, Zi-zhong; Liu, Hong-xia; Zhang, Feng-ying; Yin, Jun-qing

    2016-07-01

    A new aromatic criterion is presented to determine the aromatic degree of the high symmetric molecules. Group theory is used to explain the correlation between the aromatic degree and the value of Ring Stretching Vibration Raman Spectroscopic Frequency (RSVRSF). The calculations of the geometrical optimization, nucleus-independent chemical shifts (NICS) and values of the Raman Spectroscopy for the aromatic molecules-LnHn (L = C, Si, Ge, n = 3, 5-8) were performed using the Density Functional Theory (DFT) Method, as well as the correlations between the values of their RSVRSF and NICS values by Statistic Package for Social Science (SPSS17.0). There are high positive correlations between the theoretical calculated the NICS values and the value of the RSVRSF (A1g/A1‧) of the LnHn (L = C, Si, Ge, n = 3, 5-8). The bigger the aromatic degree, the bigger the RSVRSF is. The value of the RSVRSF is a new probe of aromaticity. Expectedly, it is predicted that the experimental determination of the aromatic degree can be achieved by the determination of the ring stretching vibration (A1g/A1‧) Raman spectrum frequencies for the aromatic target molecules.

  14. Probing QED and fundamental constants through laser spectroscopy of vibrational transitions in HD+

    CERN Document Server

    Biesheuvel, J; Hilico, L; Eikema, K S E; Ubachs, W; Koelemeij, J C J

    2016-01-01

    The simplest molecules in nature, molecular hydrogen ions in the form of H2+ and HD+, provide an important benchmark system for tests of quantum electrodynamics in complex forms of matter. Here, we report on such a test based on a frequency measurement of a vibrational overtone transition in HD+ by laser spectroscopy. We find that the theoretical and experimental frequencies are equal to within 0.6(1.1) parts per billion, which represents the most stringent test of molecular theory so far. Our measurement not only confirms the validity of high-order quantum electrodynamics in molecules, but also enables the long predicted determination of the proton-to-electron mass ratio from a molecular system, as well as improved constraints on hypothetical fifth forces and compactified higher dimensions at the molecular scale. With the perspective of comparisons between theory and experiment at the 0.01 part-per-billion level, our work demonstrates the potential of molecular hydrogen ions as a probe of fundamental physica...

  15. Probing QED and fundamental constants through laser spectroscopy of vibrational transitions in HD(.).

    Science.gov (United States)

    Biesheuvel, J; Karr, J-Ph; Hilico, L; Eikema, K S E; Ubachs, W; Koelemeij, J C J

    2016-01-01

    The simplest molecules in nature, molecular hydrogen ions in the form of H2(+) and HD(+), provide an important benchmark system for tests of quantum electrodynamics in complex forms of matter. Here, we report on such a test based on a frequency measurement of a vibrational overtone transition in HD(+) by laser spectroscopy. We find that the theoretical and experimental frequencies are equal to within 0.6(1.1) parts per billion, which represents the most stringent test of molecular theory so far. Our measurement not only confirms the validity of high-order quantum electrodynamics in molecules, but also enables the long predicted determination of the proton-to-electron mass ratio from a molecular system, as well as improved constraints on hypothetical fifth forces and compactified higher dimensions at the molecular scale. With the perspective of comparisons between theory and experiment at the 0.01 part-per-billion level, our work demonstrates the potential of molecular hydrogen ions as a probe of fundamental physical constants and laws. PMID:26815886

  16. Negative ion resonances in carbon monoxide. Probing dissociative electron attachment in CO by velocity slice imaging

    Science.gov (United States)

    Gope, Krishnendu; Tadsare, Vishvesh; Prabhudesai, Vaibhav S.; Mason, Nigel J.; Krishnakumar, E.

    2016-06-01

    Dissociative electron attachment to CO leading to the formation of O- is studied using the velocity slice imaging technique. The angular distributions we obtained for the C(3P) and the C(1D) limits are found to be considerably different from a recent set of measurements [Tian et al., Phys. Rev. A 88, 012708 (2013); Wang et al., J. Chem. Phys. 143, 066101 (2015)] using a similar technique. The analysis of our results indicate incoherent contributions from states of Σ and Π symmetries to both these dissociation channels and rules out the need to invoke coherent excitation of several resonances, in contrast to what has been done in the above publications. We try to correlate these resonances to those observed in inelastic scattering and transmission experiments. We also confirm the presence of a third dissociation channel leading to C(1S) limit.

  17. Molecular Dynamics in Dissociative Electron Attachment to CO probed by Velocity Slice Imaging

    CERN Document Server

    Nag, Pamir

    2014-01-01

    Angular distribution and kinetic energy distribution of O$^-$/CO ions formed by dissociative electron attachment process has been studied for 9, 9.5, 10, 10.5, 11, 11.5 eV incident electron energies using time sliced velocity map imaging spectrometer. The angular distribution of the ions formed with different kinetic energy for same incident electron energy are studied separately. The kinetic energy distribution is energy dependent and a second peak appears after 10.5 eV incident electron energy. We found the existence of two processes leading to the O$^-$ formation, $e^- +\\text{CO}(^1\\Sigma^+) \\rightarrow \\text{CO}^{-*} \\rightarrow \\text{O}^- (^2P) + \\text{C}^* (^3P) $ and $e^- + \\text{CO}(^1\\Sigma^+) \\rightarrow \\text{CO}^{-*} \\rightarrow \\text{O}^- (^2P) + \\text{C}^* (^1D)$. We have investigated the symmetry of intermediate state for different incident electron energies and found the presence of $\\Sigma$ and $\\Pi$ state at 9, 9.5 and 10 eV. At 10.5, 11 and 11.5 eV in the first process $\\Sigma, \\, \\Pi$ and ...

  18. Formation and properties of electroactive fullerene based films with a covalently attached ferrocenyl redox probe

    Energy Technology Data Exchange (ETDEWEB)

    Wysocka-Zolopa, Monika [Institute of Chemistry, University of Bialystok, Hurtowa 1, 15-399 Bialystok (Poland); Winkler, Krzysztof, E-mail: winkler@uwb.edu.pl [Institute of Chemistry, University of Bialystok, Hurtowa 1, 15-399 Bialystok (Poland); Caballero, Ruben [Instituto de Nanociencia, Nanotecnologia y Materiales Moleculares (INAMOL), Universidad de Castilla-La Mancha, 45071 Toledo (Spain); Langa, Fernando, E-mail: Fernando.lpuente@uclm.es [Instituto de Nanociencia, Nanotecnologia y Materiales Moleculares (INAMOL), Universidad de Castilla-La Mancha, 45071 Toledo (Spain)

    2011-06-30

    Highlights: > Formation of redox active films of ferrocene derivatives of C{sub 60} and palladium. > Fullerene moieties are covalently bonded to palladium atoms to form a polymeric network. > Electrochemical activity at both positive and negative potentials. > Charge transfer processes accompanied by transport of supporting electrolyte to and from the polymer layers. - Abstract: Redox active films have been produced via electrochemical reduction in a solution containing palladium(II) acetate and ferrocene derivatives of C{sub 60} (Fc-C{sub 60} and bis-Fc-C{sub 60}). In these films, fullerene moieties are covalently bonded to palladium atoms to form a polymeric network. Fc-C{sub 60}/Pd and bis-Fc-C{sub 60}/Pd films form uniform and relatively smooth layers on the electrode surface. These films are electrochemically active in both the positive and negative potential regions. At negative potentials, reduction of fullerene moiety takes place resulting in voltammetric behavior resembles typical of conducting polymers. In the positive potential range, oxidation of ferrocene is responsible for the formation of a sharp and symmetrical peak on the voltammograms. In this potential range, studied films behave as typical redox polymers. The charge associated with the oxidation process depends on the number of ferrocene units attached to the C{sub 60} moiety. Oxidation and reduction of these redox active films are accompanied by transport of supporting electrolyte to and from the polymer layer. Films also show a higher permeability to anions than to cations.

  19. Probing anharmonic properties of nuclear surface vibration by heavy-ion fusion reactions

    OpenAIRE

    Takigawa, N.; Hagino, K.; Kuyucak, S

    1997-01-01

    Describing fusion reactions between ^{16}O and ^{154}Dy and, between ^{16}O and ^{144}Sm by the $sd-$ and $sdf-$ interacting boson model, we show that heavy-ion fusion reactions are strongly affected by anharmonic properties of nuclear surface vibrations and nuclear shape, and thus provide a powerful method to study details of nuclear structure and dynamics.

  20. Vibrational excitons in ionophores: Experimental probes for quantum coherence-assisted ion transport and selectivity in ion channels

    CERN Document Server

    Ganim, Ziad; Vaziri, Alipasha

    2011-01-01

    Despite a large body of work, the exact molecular details underlying ion-selectivity and transport in the potassium channel have not been fully laid to rest. One major reason has been the lack of experimental methods that can probe these mechanisms dynamically on their biologically relevant time scales. Recently it was suggested that quantum coherence and its interplay with thermal vibration might be involved in mediating ion-selectivity and transport. In this work we present an experimental strategy for using time resolved infrared spectroscopy to investigate these effects. We show the feasibility by demonstrating the IR absorption and Raman spectroscopic signatures of potassium binding model molecules that mimic the transient interactions of potassium with binding sites of the selectivity filter during ion conduction. In addition to guide our experiments on the real system we have performed molecular dynamic-based simulations of the FTIR and 2DIR spectra of the entire KcsA complex, which is the largest comp...

  1. Probing roles of lipopolysaccharide, type 1 fimbria, and colanic acid in the attachment of Escherichia coli strains on inert surfaces.

    Science.gov (United States)

    Chao, Yuanqing; Zhang, Tong

    2011-09-20

    The roles of bacterial surface polymers in reversible (phase I) and irreversible (phase II) attachment (i.e., lipopolysaccharides (LPS), type 1 fimbria, and capsular colanic acid (CA)) were investigated in situ by combining fluorescence microscopy and atomic force microscopy. Fluorescence microscopy was used to evaluate the phase I attachment by counting the total number of cells on the substrata, and AFM was applied to image the phase II cells and measure the lateral detachment force to characterize phase II attachment. Also, by comparing the number of cells in phases I and II, the transformation ratio was calculated and used as an index to evaluate the roles of different polymers in the attachment process. Escherichia coli K-12 and its six mutants, which had different surface polymers in terms of LPS structures, CA contents, and type 1 fimbriae, were used as the test strains. Six different materials were applied as substrata, including glass, two metals (aluminum and stainless steel), and three plastics (polyvinyl chloride, polycarbonate, and polyethylene). The results indicated that LPS significantly enhanced phases I and II attachment as well as the transformation ratio from phase I to II. Like LPS, type 1 fimbriae largely increased the phase I attachment and the transformation ratio; however, they did not significantly influence the adhesion strength in phase II. CA had a negative effect on attachment in phases I and II by decreasing the adhered number of cells and the lateral detachment force, respectively, but had no influence on the transformation ratio. PMID:21842859

  2. Dynamic characterization of small fibers based on the flexural vibrations of a piezoelectric cantilever probe

    Science.gov (United States)

    Zhang, Xiaofei; Ye, Xuan; Li, Xide

    2016-08-01

    In this paper, we present a cantilever-probe system excited by a piezoelectric actuator, and use it to measure the dynamic mechanical properties of a micro- and nanoscale fiber. Coupling the fiber to the free end of the cantilever probe, we found the dynamic stiffness and damping coefficient of the fiber from the resonance frequency and the quality factor of the fiber-cantilever-probe system. The properties of Bacillus subtilis fibers measured using our proposed system agreed with tensile measurements, validating our method. Our measurements show that the piezoelectric actuator coupled to cantilever probe can be made equivalent to a clamped cantilever with an effective length, and calculated results show that the errors of measured natural frequency of the system can be ignored if the coupled fiber has an inclination angle of alignment of less than 10°. A sensitivity analysis indicates that the first or second resonant mode is the sensitive mode to test the sample’s dynamic stiffness, while the damping property has different sensitivities for the first four modes. Our theoretical analysis demonstrates that the double-cantilever probe is also an effective sensitive structure that can be used to perform dynamic loading and characterize dynamic response. Our method has the advantage of using amplitude-frequency curves to obtain the dynamic mechanical properties without directly measuring displacements and forces as in tensile tests, and it also avoids the effects of the complex surface structure and deformation presenting in contact resonance method. Our method is effective for measuring the dynamic mechanical properties of fiber-like one-dimensional (1D) materials.

  3. Metal-Catalyzed Chemical Reaction of Single Molecules Directly Probed by Vibrational Spectroscopy.

    Science.gov (United States)

    Choi, Han-Kyu; Park, Won-Hwa; Park, Chan-Gyu; Shin, Hyun-Hang; Lee, Kang Sup; Kim, Zee Hwan

    2016-04-01

    The study of heterogeneous catalytic reactions remains a major challenge because it involves a complex network of reaction steps with various intermediates. If the vibrational spectra of individual molecules could be monitored in real time, one could characterize the structures of the intermediates and the time scales of reaction steps without ensemble averaging. Surface-enhanced Raman scattering (SERS) spectroscopy does provide vibrational spectra with single-molecule sensitivity, but typical single-molecule SERS signals exhibit spatial heterogeneities and temporal fluctuations, making them difficult to be used in single-molecule kinetics studies. Here we show that SERS can monitor the single-molecule catalytic reactions in real time. The surface-immobilized reactants placed at the junctions of well-defined nanoparticle-thin film structures produce time-resolved SERS spectra with discrete, step-transitions of photoproducts. We interpret that such SERS-steps correspond to the reaction events of individual molecules occurring at the SERS hotspot. The analyses of the yield, dynamics, and the magnitude of such SERS steps, along with the associated spectral characteristics, fully support our claim. In addition, a model that is based on plasmonic field enhancement and surface photochemistry reproduces the key features of experimental observation. Overall, the result demonstrates that it is possible, under well-controlled conditions, to differentiate the chemical and physical processes contributing to the single-molecule SERS signals, and thus shows the use of single-molecule SERS as a tool for studying the metal-catalyzed organic reactions. PMID:26964567

  4. Interfacial Water Structure in Langmuir Monolayer and Gibbs Layer Probed by Sum Frequency Generation Vibrational Spectroscopy

    Institute of Scientific and Technical Information of China (English)

    张贞; 郭源

    2012-01-01

    Langmuir monolayer and Gibbs layer exhibit surface-active properties and it can be used as simple model systems to investigate the physicochemical properties of biological membranes. In this report, we presented the OH stretching vibration of H2O in the 4"-n-pentyl-4-cyano-p-terphenyl (5CT), nonadecanenitrile (C18CN) Langmuir monolayer and compared them with CH3CN Gibbs layer at the air/water interface with polarization SFG-VS. This study demonstrated that the hydrogen bond network is different in the Langmuir monolayer of 5CT, C18CN from CH3CN Gibbs layer at the air/water interface which showed two different water structures on the different surface layer. The results provided a deeper insight into understanding the hydrogen bond on the interfaces.

  5. Hydrogen Bonding in Ionic Liquids Probed by Linear and Nonlinear Vibrational Spectroscopy

    CERN Document Server

    Roth, C; Kerlé, D; Friedriszik, F; Lütgens, M; Lochbrunner, S; Kühn, O; Ludwig, R

    2012-01-01

    Three imidazolium-based ionic liquids of the type [Cnmim][NTf2] with varying alkyl chain lengths (n = 1, 2 and 8) at the 1 position of the imidazolium ring were studied applying IR, linear Raman, and multiplex CARS spectroscopy. The focus has been on the CH-stretching region of the imidazolium ring, which is supposed to carry information about a possible hydrogen bonding network in the ionic liquid. The measurements are compared to calculations of the corresponding anharmonic vibrational spectra for a cluster of [C2mim][NTf2] consisting of four ion pairs. The results support the hypothesis of moderate hydrogen bonding involving the C(4)-H and C(5)-H groups and somewhat stronger hydrogen bonds of the C(2)-H groups.

  6. Probing elasticity at the nanoscale: Terahertz acoustic vibration of small metal nanoparticles.

    Science.gov (United States)

    Juvé, Vincent; Crut, Aurélien; Maioli, Paolo; Pellarin, Michel; Broyer, Michel; Del Fatti, Natalia; Vallée, Fabrice

    2010-05-12

    The acoustic response of surface-controlled metal (Pt) nanoparticles is investigated in the small size range, between 1.3 and 3 nm (i.e., 75-950 atoms), using time-resolved spectroscopy. Acoustic vibration of the nanoparticles is demonstrated, with frequencies ranging from 1.1 to 2.6 THz, opening the way to the development of THz acoustic resonators. The frequencies, measured with a noncontact optical method, are in excellent agreement with the prediction of a macroscopic approach based on the continuous elastic model, together with the bulk material elastic constants. This demonstrates the validity of this model at the nanoscale and the weak impact of size reduction on the elastic properties of a material, even for nanoparticles formed by less than 100 atoms.

  7. Nitrous oxide vibrational energy relaxation is a probe of interfacial water in lipid bilayers.

    Science.gov (United States)

    Chieffo, Logan R; Shattuck, Jeffrey T; Pinnick, Eric; Amsden, Jason J; Hong, M K; Wang, Feng; Erramilli, Shyamsunder; Ziegler, Lawrence D

    2008-10-01

    Ultrafast infrared spectroscopy of N 2O is shown to be a sensitive probe of hydrophobic and aqueous sites in lipid bilayers. Distinct rates of VER of the nu 3 antisymmetric stretching mode of N 2O can be distinguished for N 2O solvated in the acyl tail, interfacial water, and bulk water regions of hydrated dioleoylphosphatidylcholine (DOPC) bilayers. The lifetime of the interfacial N 2O population is hydration-dependent. This effect is attributed to changes in the density of intermolecular states resonant with the nu 3 band ( approximately 2230 cm (-1)) resulting from oriented interfacial water molecules near the lipid phosphate. Thus, the N 2O VER rate becomes a novel and experimentally convenient tool for reporting on the structure and dynamics of interfacial water in lipids and, potentially, in other biological systems. PMID:18793010

  8. Chemotherapeutic response to cisplatin-like drugs in human breast cancer cells probed by vibrational microspectroscopy.

    Science.gov (United States)

    Batista de Carvalho, A L M; Pilling, M; Gardner, P; Doherty, J; Cinque, G; Wehbe, K; Kelley, C; Batista de Carvalho, L A E; Marques, M P M

    2016-06-23

    Studies of drug-cell interactions in cancer model systems are essential in the preclinical stage of rational drug design, which relies on a thorough understanding of the mechanisms underlying cytotoxic activity and biological effects, at a molecular level. This study aimed at applying complementary vibrational spectroscopy methods to evaluate the cellular impact of two Pt(ii) and Pd(ii) dinuclear chelates with spermine (Pt2Spm and Pd2Spm), using cisplatin (cis-Pt(NH3)2Cl2) as a reference compound. Their effects on cellular metabolism were monitored in a human triple-negative metastatic breast cancer cell line (MDA-MB-231) by Raman and synchrotron-radiation infrared microspectroscopies, for different drug concentrations (2-8 μM) at 48 h exposure. Multivariate data analysis was applied (unsupervised PCA), unveiling drug- and concentration-dependent effects: apart from discrimination between control and drug-treated cells, a clear separation was obtained for the different agents studied - mononuclear vs. polynuclear, and Pt(ii) vs. Pd(ii). Spectral biomarkers of drug action were identified, as well as the cellular response to the chemotherapeutic insult. The main effect of the tested compounds was found to be on DNA, lipids and proteins, the Pd(ii) agent having a more significant impact on proteins while its Pt(ii) homologue affected the cellular lipid content at lower concentrations, which suggests the occurrence of distinct and unconventional pathways of cytotoxicity for these dinuclear polyamine complexes. Raman and FTIR microspectroscopies were confirmed as powerful non-invasive techniques to obtain unique spectral signatures of the biochemical impact and physiological reaction of cells to anticancer agents. PMID:27063935

  9. Triggering the apoptosis of targeted human renal cancer cells by the vibration of anisotropic magnetic particles attached to the cell membrane

    Science.gov (United States)

    Leulmi, Selma; Chauchet, Xavier; Morcrette, Melissa; Ortiz, Guillermo; Joisten, Hélène; Sabon, Philippe; Livache, Thierry; Hou, Yanxia; Carrière, Marie; Lequien, Stéphane; Dieny, Bernard

    2015-09-01

    Cancer cells develop resistance to chemotherapy, and the side effects encountered seriously limit the effectiveness of treatments. For these reasons, the search for alternative therapies that target cancer cells without affecting healthy tissues is currently one of the most active areas of research on cancer. The present study focuses on a recently proposed approach for cancer cell destruction based on the targeted triggering of cancer cell spontaneous death through the mechanical vibration of anisotropic magnetic micro/nanoparticles attached to the cell membranes at low frequencies (~20 Hz) and in weak magnetic fields (~30 mT). The study was conducted in vitro, on human renal cancer cells with superparamagnetic-like particles. Three types of such particles made of NiFe or magnetite were prepared and characterized (either synthetic antiferromagnetic, vortex or polycrystalline with random grain anisotropy). The triggering of the apoptosis of these cancer cells was demonstrated with NiFe vortex particles and statistically characterized by flow-cytometry studies. The death pathway via apoptosis and not necrosis was identified by the clear observation of caspase activation.

  10. Experimental and numerical investigations on the performance of particle dampers attached to a primary structure undergoing free vibration in the horizontal and vertical directions

    Science.gov (United States)

    Wang, Yanrong; Liu, Bin; Tian, Aimei; Tang, Wei

    2016-06-01

    Particle damping (PD) has been well known for its simplicity and high efficiency in attenuating structure vibration. Recent studies on PD have focused mainly on new types of dampers and applications. Meanwhile, excitation applied to the primary structure is still limited to either horizontal or vertical direction, perpendicular or parallel to gravity. In this study, the characteristics of PD under horizontal-vertical excitations (HVE) are investigated numerically and experimentally. The particle damper, which is attached to the top free end of an L-shaped cantilever beam, is simultaneously excited in the horizontal and vertical directions in the context of free decay. An equivalent model capable of motion in both the horizontal and vertical directions is generated. Given an initial displacement disturbance, this model starts vibrating freely in the vertical plane. A code based on the 3D discrete element method is programmed, and the high coincidence between the numerical and experimental results shows that this equivalent model is capable of high-fidelity simulation for PD under HVE. Parametric studies have been implemented to characterize the basic nonlinear damping capacity of particle dampers under this new operating condition. The effects of seven dimensionless independent parameters on the specific damping capacity (SDC) are investigated, including dimensionless acceleration amplitude, particle mass ratio, dimensionless horizontal and vertical impact clearances, coefficients of friction and restitution, and amplitude ratio of the horizontal excitation to the vertical excitation. The results show that the basic damping properties of PD under HVE are similar to those of PD under only vertical excitation. However, PD under HVE signifies its own characteristics because of the existence of horizontal excitation: (1) The impact clearances in both the horizontal and vertical directions have significant effects on the SDC because of the significant increase in oblique

  11. Structure-Dependent Vibrational Dynamics of Mg(BH4)2 Polymorphs Probed with Neutron Vibrational Spectroscopy and First-Principles Calculations

    Energy Technology Data Exchange (ETDEWEB)

    Dimitrievska, Mirjana; White, James L.; Zhou, Wei; Stavila, Vitalie; Klebanoff, Leonard E.; Udovic, Terrence J.

    2016-09-28

    The structure-dependent vibrational properties of different Mg(BH4)2 polymorphs (..alpha.., ..beta.., ..gamma.., and ..delta.. phases) were investigated with a combination of neutron vibrational spectroscopy (NVS) measurements and density functional theory (DFT) calculations, with emphasis placed on the effects of the local structure and orientation of the BH4- anions. DFT simulations closely match the neutron vibrational spectra. The main bands in the low-energy region (20-80 meV) are associated with the BH4- librational modes. The features in the intermediate energy region (80-120 meV) are attributed to overtones and combination bands arising from the lower-energy modes. The features in the high-energy region (120-200 meV) correspond to the BH4- symmetric and asymmetric bending vibrations, of which four peaks located at 140, 142, 160, and 172 meV are especially intense. There are noticeable intensity distribution variations in the vibrational bands for different polymorphs. This is explained by the differences in the spatial distribution of BH4- anions within various structures. An example of the possible identification of products after the hydrogenation of MgB2, using NVS measurements, is presented. These results provide fundamental insights of benefit to researchers currently studying these promising hydrogen-storage materials.

  12. Positron-attachment to small molecules: Vibrational enhancement of positron affinities with configuration interaction level of multi-component molecular orbital approach

    Energy Technology Data Exchange (ETDEWEB)

    Tachikawa, Masanori [Quantum Chemistry Division, Graduate School of NanoBioScience, Yokohama City University, 22-2 Seto, Kanazawa, Yokohama 236-0027 (Japan)

    2015-12-31

    To theoretically demonstrate the binding of a positron to small polarized molecules, we have calculated the vibrational averaged positron affinity (PA) values along the local vibrational contribution with the configuration interaction level of multi-component molecular orbital method. This method can take the electron-positron correlation contribution into account through single electronic - single positronic excitation configurations. The PA values are enhanced by including the local vibrational contribution from vertical PA values due to the anharmonicity of the potential.

  13. Probing highly-obscured galaxy nuclei with vibrationally excited HCN - Extreme luminosity densities inside self-absorbed v=0 HCN and HCO+

    CERN Document Server

    Aalto, S; Gonzalez-Alfonso, E; Muller, S; Sakamoto, K; Fuller, G A; Garcia-Burillo, S; van der Werf, P; Neri, R; Spaans, M; Combes, F; Viti, S; Muehle, S; Armus, L; Evans, A; Sturm, E; Cernicharo, J; Henkel, C; Greve, T R

    2015-01-01

    We present high resolution (0."4) IRAM PdBI and ALMA mm and submm observations of the (Ultra) Luminous Infrared Galaxies ((U)LIRGs) IRAS17208-0014, Arp220, IC860 and Zw049.057 that reveal intense line emission from vibrationally excited (v2=1) J=3-2 and 4-3 HCN. The emission is emerging from buried, compact (r5e13 Lsun/kpc2. These nuclei are likely powered by accreting supermassive black holes (SMBHs) and/or hot (>200 K) extreme starbursts. Vibrational, v2=1, lines of HCN are excited by intense 14 micron mid-infrared emission and are excellent probes of the dynamics, masses and physical conditions of (U)LIRG nuclei when H2 column densities exceed 1e24 cm-2. It is clear that these lines open up a new interesting avenue to gain access to the most obscured AGNs and starbursts. Vibrationally excited HCN acts as a proxy for the absorbed mid-infrared emission from the embedded nuclei, which allows for reconstruction of the intrinsic, hotter dust SED. In contrast, the ground vibrational state (v=0), J=3-2 and 4-3 ro...

  14. A System for a Water Thickness Gauging in a Bellows Tube was Developed, by using a Special UT Probe Attachment and an Immersion Ultrasonic Inspection

    International Nuclear Information System (INIS)

    A thickness gauging for most engineering materials can be measured ultrasonically, including metals, plastics, ceramics, composites, epoxies, and glass, as well as liquid levels and the thickness of certain biological specimens. Precision ultrasonic thickness gauges for liquid levels usually operate at frequencies between 500 KHz and 100 MHZ, by using piezoelectric transducers to generate bursts of sound waves when excited by electrical pulses. In this experiment, a residual water level gauging in a bellow tube is measured by using an immersion ultrasonic technique and a special UT probe attachment. There are two kinds of transducers according to the water thickness. In this case, the enhanced S/N ratio could be obtained from the 15 MHz frequency transducer more than a 2.25 MHz frequency transducer, because of the good resolution of the transducer with a wide band frequency, and we could also obtain the frequency domain from each time domain signal by the FFT function. It is possible to analyze the signal patterns and some information from the frequency domain. (authors)

  15. Probing Structural Transitions in the Intrinsically Disordered C-Terminal Domain of the Measles Virus Nucleoprotein by Vibrational Spectroscopy of Cyanylated Cysteines

    Science.gov (United States)

    Bischak, Connor G.; Longhi, Sonia; Snead, David M.; Costanzo, Stéphanie; Terrer, Elodie; Londergan, Casey H.

    2010-01-01

    Four single-cysteine variants of the intrinsically disordered C-terminal domain of the measles virus nucleoprotein (NTAIL) were cyanylated at cysteine and their infrared spectra in the C≡N stretching region were recorded both in the absence and in the presence of one of the physiological partners of NTAIL, namely the C-terminal X domain (XD) of the viral phosphoprotein. Consistent with previous studies showing that XD triggers a disorder-to-order transition within NTAIL, the C≡N stretching bands of the infrared probe were found to be significantly affected by XD, with this effect being position-dependent. When the cyanylated cysteine side chain is solvent-exposed throughout the structural transition, its changing linewidth reflects a local gain of structure. When the probe becomes partially buried due to binding, its frequency reports on the mean hydrophobicity of the microenvironment surrounding the labeled side chain of the bound form. The probe moiety is small compared to other common covalently attached spectroscopic probes, thereby minimizing possible steric hindrance/perturbation at the binding interface. These results show for the first time to our knowledge the suitability of site-specific cysteine mutagenesis followed by cyanylation and infrared spectroscopy to document structural transitions occurring within intrinsically disordered regions, with regions involved in binding and folding being identifiable at the residue level. PMID:20816082

  16. 2D IR Spectroscopy of Histidine: Probing Side-Chain Structure and Dynamics via Backbone Amide Vibrations

    OpenAIRE

    Ghosh, Ayanjeet; Tucker, Matthew J.; Gai, Feng

    2014-01-01

    It is well known that histidine is involved in many biological functions due to the structural versatility of its side chain. However, probing the conformational transitions of histidine in proteins, especially those occurring on an ultrafast time scale, is difficult. Herein we show, using a histidine dipeptide as a model, that it is possible to probe the tautomer and protonation status of a histidine residue by measuring the two-dimensional infrared (2D IR) spectrum of its amide I vibrationa...

  17. Optically probing Al—O and O—H vibrations to characterize water adsorption and surface reconstruction on α-alumina: An experimental and theoretical study

    Energy Technology Data Exchange (ETDEWEB)

    Tong, Yujin, E-mail: tong@fhi-berlin.mpg.de; Kirsch, Harald; Wolf, Martin; Campen, R. Kramer, E-mail: campen@fhi-berlin.mpg.de [Fritz Haber Institute of the Max Planck Society, 14195 Berlin (Germany); Wirth, Jonas; Saalfrank, Peter [Institute of Chemistry, University of Potsdam, 14476 Potsdam OT Golm (Germany)

    2015-02-07

    Oxide/water interfaces are ubiquitous in a wide variety of applications and the environment. Despite this ubiquity, and attendant decades of study, gaining molecular level insight into water/oxide interaction has proven challenging. In part, this challenge springs from a lack of tools to concurrently characterize changes in surface structure (i.e., water/oxide interaction from the perspective of the solid) and O—H population and local environment (i.e., water/oxide interaction from the water perspective). Here, we demonstrate the application of surface specific vibrational spectroscopy to the characterization of the interaction of the paradigmatic α-Al{sub 2}O{sub 3}(0001) surface and water. By probing both the interfacial Al—O (surface phonon) and O—H spectral response, we characterize this interaction from both perspectives. Through electronic structure calculation, we assign the interfacial Al—O response and rationalize its changes on surface dehydroxylation and reconstruction. Because our technique is all-optical and interface specific, it is equally applicable to oxide surfaces in vacuum, ambient atmospheres and at the solid/liquid interface. Application of this approach to additional alumina surfaces and other oxides thus seems likely to significantly expand our understanding of how water meets oxide surfaces and thus the wide variety of phenomena this interaction controls.

  18. Product Attachment

    OpenAIRE

    Mugge, R.

    2007-01-01

    The topic of this doctoral research is the concept of product attachment for ordinary consumer durables. Product attachment is defined as the strength of the emotional bond a consumer experiences with a specific product. Specifically, the research investigated how this bond develops over time and the relationship between product attachment and product lifetime. In addition, we studied which determinants may affect the strength of the emotional bond with products and uncovered the role of the ...

  19. Product Attachment

    NARCIS (Netherlands)

    Mugge, R.

    2007-01-01

    The topic of this doctoral research is the concept of product attachment for ordinary consumer durables. Product attachment is defined as the strength of the emotional bond a consumer experiences with a specific product. Specifically, the research investigated how this bond develops over time and th

  20. Vibration control of multi-degrees-of-freedom system with dynamic absorbers based on power flow

    Institute of Scientific and Technical Information of China (English)

    WANG Quanjuan; HUANG Wenhua; XIA Songbo; LI Jimin; SUN Zhizhuo

    2003-01-01

    In accordance with a multiple degrees of freedom vibration system with dynamicvibration absorbers (DVAs), an equivalent admittance matrix and the power flows input majorstructure and minor structure are deduced on the basis of the theories of structure mobility.Furthermore, regarding the net power flow of main vibration system as the controlled object,probed into are the single and multiple model controls of multi-degrees-of-freedom system withone or several absorbers attached. And the control mechanism and effect of dynamic vibrationabsorbers are revealed.

  1. 2008 Vibrational Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Philip J. Reid

    2009-09-21

    The conference focuses on using vibrational spectroscopy to probe structure and dynamics of molecules in gases, liquids, and interfaces. The goal is to bring together a collection of researchers who share common interests and who will gain from discussing work at the forefront of several connected areas. The intent is to emphasize the insights and understanding that studies of vibrations provide about a variety of systems.

  2. Facile sonochemical synthesis and morphology control of CePO{sub 4} nanostructures via an oriented attachment mechanism: Application as luminescent probe for selective sensing of Pb{sup 2+} ion in aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Shiralizadeh Dezfuli, Amin [Center of Excellence in Electrochemistry, Faculty of Chemistry, University of Tehran, Tehran (Iran, Islamic Republic of); Ganjali, Mohammad Reza, E-mail: ganjali@khayam.ut.ac.ir [Center of Excellence in Electrochemistry, Faculty of Chemistry, University of Tehran, Tehran (Iran, Islamic Republic of); Biosensor Research Center, Endocrinology and Metabolism Molecular–Cellular Sciences Institute, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Norouzi, Parviz [Center of Excellence in Electrochemistry, Faculty of Chemistry, University of Tehran, Tehran (Iran, Islamic Republic of); Biosensor Research Center, Endocrinology and Metabolism Molecular–Cellular Sciences Institute, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of)

    2014-09-01

    CePO{sub 4} nanostructures with hexagonal phase were controllably synthesized using Ce(NO{sub 3}){sub 3} reaction with NH{sub 4}H{sub 2}PO{sub 4} through a sonochemical method by simply varying the reaction conditions. By adding ethanol and polyethylene glycol (PEG), coral-reef nanostructures (CRNs) were synthesized and controlling over pH caused to nanorods/nanowires. Oriented attachment (OA) is proposed as dominant mechanism on the growth of nanostructures which is in competition with Ostwald ripening (OR). The crystal structure and morphology of the nanostructures were characterized by X-ray diffraction (XRD) and field-emission scanning electron microscopy (FE-SEM), respectively. The luminescent properties of CePO{sub 4} with different morphologies have been studied. Among the nanostructures, nanoparticles with the highest intensity of fluorescent have been used as luminescent probe for selective sensing of Pb{sup 2+} ion in aqueous solution. - Highlights: • Facile sonochemical method has been used for synthesis of CePO{sub 4} nanostructures. • Coral-reef as a new morphology of nanostructures is introduced. • CePO{sub 4} NPs have been used as luminescent probe for selective sensing of Pb{sup 2+} ion.

  3. Vibrational Spectroscopy of Biomembranes

    Science.gov (United States)

    Schultz, Zachary D.; Levin, Ira W.

    2011-07-01

    Vibrational spectroscopy, commonly associated with IR absorption and Raman scattering, has provided a powerful approach for investigating interactions between biomolecules that make up cellular membranes. Because the IR and Raman signals arise from the intrinsic properties of these molecules, vibrational spectroscopy probes the delicate interactions that regulate biomembranes with minimal perturbation. Numerous innovative measurements, including nonlinear optical processes and confined bilayer assemblies, have provided new insights into membrane behavior. In this review, we highlight the use of vibrational spectroscopy to study lipid-lipid interactions. We also examine recent work in which vibrational measurements have been used to investigate the incorporation of peptides and proteins into lipid bilayers, and we discuss the interactions of small molecules and drugs with membrane structures. Emerging techniques and measurements on intact cellular membranes provide a prospective on the future of vibrational spectroscopic studies of biomembranes.

  4. Probing the Vibrational Spectroscopy of the Deprotonated Thymine Radical by Photodetachment and State-Selective Autodetachment Photoelectron Spectroscopy via Dipole-Bound States

    Science.gov (United States)

    Huang, Dao-Ling; Zhu, Guo-Zhu; Wang, Lai-Sheng

    2016-06-01

    Deprotonated thymine can exist in two different forms, depending on which of its two N sites is deprotonated: N1[T-H]^- or N3[T-H]^-. Here we report a photodetachment study of the N1[T-H]^- isomer cooled in a cryogenic ion trap and the observation of an excited dipole-bound state. Eighteen vibrational levels of the dipole-bound state are observed, and its vibrational ground state is found to be 238 ± 5 wn below the detachment threshold of N1[T-H]^-. The electron affinity of the deprotonated thymine radical (N1[T-H]^.) is measured accruately to be 26 322 ± 5 wn (3.2635 ± 0.0006 eV). By tuning the detachment laser to the sixteen vibrational levels of the dipole-bound state that are above the detachment threshold, highly non-Franck-Condon resonant-enhanced photoelectron spectra are obtained due to state- and mode-selective vibrational autodetachment. Much richer vibrational information is obtained for the deprotonated thymine radical from the photodetachment and resonant-enhanced photoelectron spectroscopy. Eleven fundamental vibrational frequencies in the low-frequency regime are obtained for the N1[T-H]^. radical, including the two lowest-frequency internal rotational modes of the methyl group at 70 ± 8 wn and 92 ± 5 wn. D. L. Huang, H. T. Liu, C. G. Ning, G. Z. Zhu and L. S. Wang, Chem. Sci., 6, 3129-3138 (2015)

  5. Experimental and modeling study of thermal rate coefficients and cross sections for electron attachment to C(60).

    Science.gov (United States)

    Viggiano, Albert A; Friedman, Jeffrey F; Shuman, Nicholas S; Miller, Thomas M; Schaffer, Linda C; Troe, Jürgen

    2010-05-21

    Thermal electron attachment to C(60) has been studied by relative rate measurements in a flowing afterglow Langmuir probe apparatus. The rate coefficients of the attachment k(1) are shown to be close to 10(-6) cm(3) s(-1) with a small negative temperature coefficient. These results supersede measurements from the 1990s which led to much smaller values of k(1) with a large positive temperature coefficient suggesting an activation barrier. Theoretical modeling of k(1) in terms of generalized Vogt-Wannier capture theory shows that k(1) now looks more consistent with measurements of absolute attachment cross sections sigma(at) than before. The comparison of capture theory and experimental rate or cross section data leads to empirical correction factors, accounting for "intramolecular vibrational relaxation" or "electron-phonon coupling," which reduce k(1) below the capture results and which, on a partial wave-selected level, decrease with increasing electron energy.

  6. Experimental and modeling study of thermal rate coefficients and cross sections for electron attachment to C(60).

    Science.gov (United States)

    Viggiano, Albert A; Friedman, Jeffrey F; Shuman, Nicholas S; Miller, Thomas M; Schaffer, Linda C; Troe, Jürgen

    2010-05-21

    Thermal electron attachment to C(60) has been studied by relative rate measurements in a flowing afterglow Langmuir probe apparatus. The rate coefficients of the attachment k(1) are shown to be close to 10(-6) cm(3) s(-1) with a small negative temperature coefficient. These results supersede measurements from the 1990s which led to much smaller values of k(1) with a large positive temperature coefficient suggesting an activation barrier. Theoretical modeling of k(1) in terms of generalized Vogt-Wannier capture theory shows that k(1) now looks more consistent with measurements of absolute attachment cross sections sigma(at) than before. The comparison of capture theory and experimental rate or cross section data leads to empirical correction factors, accounting for "intramolecular vibrational relaxation" or "electron-phonon coupling," which reduce k(1) below the capture results and which, on a partial wave-selected level, decrease with increasing electron energy. PMID:20499963

  7. Investigation for parametric vibration of rolling mill

    Institute of Scientific and Technical Information of China (English)

    唐华平; 丁睿; 吴运新; 钟掘

    2002-01-01

    The vibration unsteady condition of rolling mill caused by flexural vibration of strip has been investigated. The parametric flexural vibration equation of rolled strip has been established. The parametric flexural vibration stability of rolled strip has been studied and the regions of stability and unstability have been determined based on Floquet theory and perturbation method. The flexural-vibration of strip is unstable when the frequency of variable tension is two times as the natural frequency of flexural-vibration strip. The characteristic of current in a temp driving motor's main loop has been studied and tested, it has been proved that there are 6 harmonic component and 12 harmonic component in main loop of driving motor electricity. The vertical vibration of working roller has been tested, the test result approves that the running unsteady is caused by parametric vibration. It attaches importance to the parametric vibration of rolling mill.

  8. Vibration Mitigation of Nonlinear Vibrating Structures using Nonlinear Energy Sinks

    OpenAIRE

    Viguié, Régis; Peeters, Maxime; Kerschen, Gaëtan; Golinval, Jean-Claude

    2008-01-01

    The tuned mass damper (TMD) is a simple and efficient device, but it is only effective when it is precisely tuned to the frequency of a vibration mode. Because nonlinear vibrating structures have resonant frequencies that vary with the amount of total energy in the system, the efficiency of a TMD is questionable in this case. In the present study, the performance of an essentially nonlinear attachment, termed a nonlinear energy sink (NES), is assessed. It is shown that, unlike the TMD, an ...

  9. Clinical evaluation of mandibular implant overdentures via Locator implant attachment and Locator bar attachment

    Science.gov (United States)

    Seo, Yong-Ho; Bae, Eun-Bin; Kim, Jung-Woo; Lee, So-Hyoun; Jeong, Chang-Mo; Jeon, Young-Chan

    2016-01-01

    PURPOSE The aim of this study was to evaluate the clinical findings and patient satisfaction on implant overdenture designed with Locator implant attachment or Locator bar attachment in mandibular edentulous patients. MATERIALS AND METHODS Implant survival rate, marginal bone loss, probing depth, peri-implant inflammation, bleeding, plaque, calculus, complications, and satisfaction were evaluated on sixteen patients who were treated with mandibular overdenture and have used it for at least 1 year (Locator implant attachment: n=8, Locator bar attachment: n=8). RESULTS Marginal bone loss, probing depth, plaque index of the Locator bar attachment group were significantly lower than the Locator implant attachment group (P.05). The replacement of the attachment components was the most common complication in both groups. Although there was no correlation between marginal bone loss and plaque index, a significant correlation was found between marginal bone loss and probing depth. CONCLUSION The Locator bar attachment group indicates lesser marginal bone loss and need for maintenance, as compared with the Locator implant attachment group. This may be due to the splinting effect among implants rather than the types of Locator attachment. PMID:27555901

  10. Direct observation of the cyclic dimer in liquid acetic acid by probing the C=O vibration with ultrafast coherent Raman spectroscopy.

    Science.gov (United States)

    Lütgens, Matthias; Friedriszik, Frank; Lochbrunner, Stefan

    2014-09-01

    We present a comparison of spontaneous Raman and ultrafast coherent anti-Stokes Raman scattering (CARS) spectra of the C=O vibration of liquid acetic acid. The former technique cannot clearly reveal the number of contributions in the spectrum. However, the additional time and spectrally resolved CARS experiment supports strictly the existence of four modes, which proves the coexistence of more than one H-bonded configuration in liquid acetic acid. A comparably slowly dephasing mode which is obscured by a broad band in the linear Raman spectrum is assigned to the cyclic dimer and can be observed freed from all other contributions by ultrafast CARS.

  11. Paternal Attachment, Parenting Beliefs and Children's Attachment

    Science.gov (United States)

    Howard, Kimberly S.

    2010-01-01

    Relationships between fathers' romantic attachment style, parenting beliefs and father-child attachment security and dependence were examined in a diverse sample of 72 fathers of young children. Paternal romantic attachment style was coded based on fathers' endorsement of a particular style represented in the Hazan and Shaver Three-Category…

  12. Vibrational spectroscopy at electrified interfaces

    CERN Document Server

    Wieckowski, Andrzej; Braunschweig, Björn

    2013-01-01

    Reviews the latest theory, techniques, and applications Surface vibrational spectroscopy techniques probe the structure and composition of interfaces at the molecular level. Their versatility, coupled with their non-destructive nature, enables in-situ measurements of operating devices and the monitoring of interface-controlled processes under reactive conditions. Vibrational Spectroscopy at Electrified Interfaces explores new and emerging applications of Raman, infrared, and non-linear optical spectroscopy for the study of charged interfaces. The book draws from hu

  13. Femtosecond nonlinear spectroscopy at surfaces: Second-harmonic probing of hole burning at the Si(111)7x7 surface and Fourier-transform sum-frequency vibrational spectroscopy

    International Nuclear Information System (INIS)

    The high temporal resolution and broad bandwidth of a femtosecond laser system are exploited in a pair of nonlinear optical studies of surfaces. The dephasing dynamics of resonances associated with the adatom dangling bonds of the Si(111)7 x 7 surface are explored by transient second-harmonic hole burning, a process that can be described as a fourth-order nonlinear optical process. Spectral holes produced by a 100 fs pump pulse at about 800 nm are probed by the second harmonic signal of a 100 fs pulse tunable around 800 nm. The measured spectral holes yield homogeneous dephasing times of a few tens of femtoseconds. Fits with a Lorentzian spectral hole centered at zero probe detuning show a linear dependence of the hole width on pump fluence, which suggests that charge carrier-carrier scattering dominates the dephasing dynamics at the measured excitation densities. Extrapolation of the deduced homogeneous dephasing times to zero excitation density yields an intrinsic dephasing time of ∼ 70 fs. The presence of a secondary spectral hole indicates that scattering of the surface electrons with surface optical phonons at 570 cm-1 occurs within the first 200 fs after excitation. The broad bandwidth of femtosecond IR pulses is used to perform IR-visible sum frequency vibrational spectroscopy. By implementing a Fourier-transform technique, we demonstrate the ability to obtain sub-laser-bandwidth spectral resolution. FT-SFG yields a greater signal when implemented with a stretched visible pulse than with a femtosecond visible pulse. However, when compared with multichannel spectroscopy using a femtosecond IR pulse but a narrowband visible pulse, Fourier-transform SFG is found to have an inferior signal-to-noise ratio. A mathematical analysis of the signal-to-noise ratio illustrates the constraints on the Fourier-transform approach

  14. Femtosecond nonlinear spectroscopy at surfaces: Second-harmonic probing of hole burning at the Si(111)7x7 surface and fourier-transform sum-frequency vibrational spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    McGuire, John Andrew

    2004-11-24

    The high temporal resolution and broad bandwidth of a femtosecond laser system are exploited in a pair of nonlinear optical studies of surfaces. The dephasing dynamics of resonances associated with the adatom dangling bonds of the Si(111)7 x 7 surface are explored by transient second-harmonic hole burning, a process that can be described as a fourth-order nonlinear optical process. Spectral holes produced by a 100 fs pump pulse at about 800 nm are probed by the second harmonic signal of a 100 fs pulse tunable around 800 nm. The measured spectral holes yield homogeneous dephasing times of a few tens of femtoseconds. Fits with a Lorentzian spectral hole centered at zero probe detuning show a linear dependence of the hole width on pump fluence, which suggests that charge carrier-carrier scattering dominates the dephasing dynamics at the measured excitation densities. Extrapolation of the deduced homogeneous dephasing times to zero excitation density yields an intrinsic dephasing time of {approx} 70 fs. The presence of a secondary spectral hole indicates that scattering of the surface electrons with surface optical phonons at 570 cm{sup -1} occurs within the first 200 fs after excitation. The broad bandwidth of femtosecond IR pulses is used to perform IR-visible sum frequency vibrational spectroscopy. By implementing a Fourier-transform technique, we demonstrate the ability to obtain sub-laser-bandwidth spectral resolution. FT-SFG yields a greater signal when implemented with a stretched visible pulse than with a femtosecond visible pulse. However, when compared with multichannel spectroscopy using a femtosecond IR pulse but a narrowband visible pulse, Fourier-transform SFG is found to have an inferior signal-to-noise ratio. A mathematical analysis of the signal-to-noise ratio illustrates the constraints on the Fourier-transform approach.

  15. Adult Attachment and Psychotherapy

    OpenAIRE

    Rietzschel, Julia

    2012-01-01

    This thesis explores the association between adult attachment and psychological therapy by examining attachment as an outcome variable of therapy, as well as a predictor of therapy outcome. The literature review systematically explores research that has examined changes in attachment representations during psychological therapy. The purpose of the review is to enhance understanding of change processes in adult attachment and to provide empirical support to the premises of attachment theory. I...

  16. Attachment behavior in rats

    OpenAIRE

    Sigling, H.O.

    2009-01-01

    This thesis describes studies into the rat as an animal model for attachment, along the lines of Bowlby's attachment theory. First, the relation between attachment and human psychopathology is reviewed. The conclusion is that psychopathology is more frequent in insecure attached persons and that there is a relationship between specific types of insecure attachment and specific types of psychiatric disorders. Next, a reinterpretation of the literature on social preference experiments in rodent...

  17. Ship Vibrations

    DEFF Research Database (Denmark)

    Sørensen, Herman

    1997-01-01

    Methods for calculating natural frequencies for ship hulls and for plates and panels.Evaluation of the risk for inconvenient vibrations on board......Methods for calculating natural frequencies for ship hulls and for plates and panels.Evaluation of the risk for inconvenient vibrations on board...

  18. Adult attachment styles

    Directory of Open Access Journals (Sweden)

    Maša Žvelc

    2007-01-01

    Full Text Available Theory of attachment primarily described early relationships between a child and his caretakers. In the last twenty years there is a growing interest in adult attachment research. Theories and research findings of adult attachment stem from two different methodological approaches. The first approach measures adult attachment through Adult Attachment Interview (AAI; Main, 1991 where the attachment is assessed through the narratives of adult people of their early child experiences with their primary caretakers. The second approach measures adult attachment with the help of self-evaluative questionnaires, developed by (a Hazan and Shaver (1987 who started this approach in the field of personality and social psychology, and (b Bartholomew and Horowitz (1991. Research shows that there is significant correlation between early and adult attachment style. Attachment styles are passed from generation to generation. Basic adult attachment styles are: securely attached, preoccupied, fearful-avoidant, dismissing-avoidant and disorganized. Previous research using Barholomew and Horowitz (1991 Relationship Questionnaire on 176 Slovenian students showed that 48% students are securely attached, 29% are fearful-avoidant, 10% are dismissing-avoidant, and 13% have preoccupied attachment style. Theory of attachment is very useful for understanding the behavior and subjective experiences of children and adults. It is applicable to different contexts (psychotherapy, counseling, education .... The paper proposes further research focused on integration of adult attachment styles and types of object relations measured by Test of object relations (Žvelc, 1998 and Pictorial test of Separation and Individuation (Žvelc, 2003.

  19. Vibration characteristics of BWR primary containment vessel

    International Nuclear Information System (INIS)

    This paper reports on a part of a seismic proving test of a BWR Primary Containment Vessel (PCV), a vibration analysis that is carried out considering the effect of reinforcement around attached masses such as equipment hatches and a personnel airlock. A deflected shape with the local attached masses and reinforcement is expanded using free vibration modes of an axisymmetric PCV without attached masses and reinforcement. The free vibration modes are calculated considering a coupling effect between the PCV shell and suppression pool water using conical shell finite elements and ring fluid elements. The same expanding functions and free vibration modes are used to express strain energy, kinetic energy and work done by inertia forces due to input acceleration considering locally varying thickness of the PCV and attached masses. The equations of motion are obtained by substituting the strain energy, kinetic energy, and work done by inertia forces into the Lagrange's equation. Calculated natural frequencies, free vibration modes and frequency response functions are compared with numerical results obtained by a general shell finite element analysis and with test results using the large-scale high-performance vibration table of Tadotsu Engineering Laboratory, Nuclear Power Engineering Test Center (NUPEC). The comparison shows a reasonable agreement, leading to better understanding of the dynamic characteristics of the BWR PCV

  20. Electron-attachment processes

    International Nuclear Information System (INIS)

    Topics covered include: (1) modes of production of negative ions, (2) techniques for the study of electron attachment processes, (3) dissociative electron attachment to ground-state molecules, (4) dissociative electron attachment to hot molecules (effects of temperature on dissociative electron attachment), (5) molecular parent negative ions, and (6) negative ions formed by ion-pair processes and by collisions of molecules with ground state and Rydberg atoms

  1. Belt attachment and system

    Science.gov (United States)

    Schneider, Abraham D.; Davidson, Erick M.

    2016-02-02

    Disclosed herein is a belt assembly including a flexible belt with an improved belt attachment. The belt attachment includes two crossbars spaced along the length of the belt. The crossbars retain bearings that allow predetermined movement in six degrees of freedom. The crossbars are connected by a rigid body that attaches to the bearings. Implements that are attached to the rigid body are simply supported but restrained in pitching rotation.

  2. Attachment Without Fear

    OpenAIRE

    Bell, David C.

    2009-01-01

    John Bowlby hypothesized an attachment system that interacts with caregiving, exploration, and fear systems in the brain, with a particular emphasis on fear. Neurobiological research confirms many of his hypotheses and also raises some new questions. A psychological model based on this neurobiological research is presented here. The model extends conventional attachment theory by describing additional attachment processes independent of fear. In this model, the attachment elements of trust, o...

  3. Special Attachments. Module 19.

    Science.gov (United States)

    South Carolina State Dept. of Education, Columbia. Office of Vocational Education.

    This module on special attachments, one in a series dealing with industrial sewing machines, their attachments, and operation, covers four topics: gauges; cording attachment; zipper foot; and hemming, shirring, and binding. For each topic these components are provided: an introduction, directions, an objective, learning activities, student…

  4. Precision Attachment: Retained Overdenture

    OpenAIRE

    Jayasree, K; Mrs.M.Bharathi; Nag, V. Dileep; B. Vinod

    2011-01-01

    Precision attachments are small interlocking devices to connect prosthesis and abutments that offer a variety of solutions to the challenge of balance between functional stability and cosmetic appeal. Precision attachments have wide applications, used in fixed removable bridge, removable partial dentures, overdentures, implant retained overdentures, and maxillofacial prosthesis. Attachment retained overdentures helps in distribution of masticatory forces, minimizes trauma to abutments and sof...

  5. Attachment and Psychopathology

    Directory of Open Access Journals (Sweden)

    Mehmet Fatih Ustundag

    2011-06-01

    Full Text Available The type of attachment defined in the early stages of life and thought to be continuous, is a phenomenon that shapes the pattern of how a person makes contact with others. The clinical appearance of every type of attachment is different and each one has prospective and retrospective phenomenological reflections. In all stages of life and in close relationships, it can be observed if a person gets in close contact with someone else and if this relation bears supportive and protective qualities. According to attachment theorists, once it is defined as safe or unsafe during nursing period, it shows little change. Starting from Bowlby’s work, unsafe attachment type is considered as the determining factor of psychopathology in the later periods of life, while safe attachment is considered as in relation with healthy processes. The nature’s original model is safe attachment. Anxious/indecisive attachment, an unsafe attachment type, is associated with anxiety disorders and depressive disorder, while avoidant attachment is associated with behavior disorder and other extroverted pathologies. Disorganized/disoriented attachment is considered to be together with dissociative disorder. The aim of this paper is to review attachment theory and the relation between attachment and psychopathology.

  6. Effects of pitch accents in attachment ambiguity resolution

    OpenAIRE

    Lee, Eun-Kyung; Watson, Duane G.

    2011-01-01

    Previous work has found that listeners prefer to attach ambiguous syntactic constituents to nouns produced with a pitch accent (Schafer et al., 1996). This study examines what factors underlie previously established accent attachment effects by testing whether these effects are driven by a preference to attach syntactic constituents to new or important information (the Syntax Hypothesis) or whether there is a bias to respond to post-sentence probe questions with an accented word (the Salience...

  7. Urban vibrations

    DEFF Research Database (Denmark)

    Morrison, Ann; Knudsen, L.; Andersen, Hans Jørgen

    2012-01-01

      lab   studies   in   that   we   found   a   decreased   detection   rate   in   busy   environments.   Here   we   test   with   a   much   larger   sample   and   age   range,   and   contribute   with   the   first   vibration  sensitivity  testing  outside  the  lab  in  an  urban   public......In   this   paper   we   describe   a   field   study   conducted   with   a   wearable   vibration   belt   where   we   test   to   determine   the   vibration   intensity   sensitivity   ranges   on   a   large   diverse   group   of   participants   with   evenly   distributed  ages  and...

  8. Blade attachment assembly

    Science.gov (United States)

    Garcia-Crespo, Andres Jose; Delvaux, John McConnell; Miller, Diane Patricia

    2016-05-03

    An assembly and method for affixing a turbomachine rotor blade to a rotor wheel are disclosed. In an embodiment, an adaptor member is provided disposed between the blade and the rotor wheel, the adaptor member including an adaptor attachment slot that is complementary to the blade attachment member, and an adaptor attachment member that is complementary to the rotor wheel attachment slot. A coverplate is provided, having a coverplate attachment member that is complementary to the rotor wheel attachment slot, and a hook for engaging the adaptor member. When assembled, the coverplate member matingly engages with the adaptor member, and retains the blade in the adaptor member, and the assembly in the rotor wheel.

  9. Vibrating minds

    CERN Multimedia

    2009-01-01

    Ed Witten is one of the leading scientists in the field of string theory, the theory that describes elementary particles as vibrating strings. This week he leaves CERN after having spent a few months here on sabbatical. His wish is that the LHC will unveil supersymmetry.

  10. Vibrating Manipulation

    Institute of Scientific and Technical Information of China (English)

    SHEN Guo-quan; CUI Yi-jun

    2003-01-01

    @@ As a manipulation with unique therapeutic effect in TCM Tuina manipulations, Vibrating manipulation has significantly stronger effection on viscera, blood vessel, smooth muscle and gland secretion than other Tuina manipulations and it is mainly used in internal medicine, gynecology and miscellaneous diseases.

  11. Vibration sensor

    OpenAIRE

    Matěj, J.

    2015-01-01

    This paper lays out a design of a system for reading the radar antenna gearbox vibrations. Firstly it names different types of sensors and defines their suitability for this usage. It describes their important electric and frequency properties. Secondly it shows a design of the data transmission system from the transducer to a computer and describes measured data changes according to the gearbox faults.

  12. Vibration transmission characteristics of the legs of freely standing honeybees

    DEFF Research Database (Denmark)

    Rohrseitz, Kristin; Kilpinen, Ole

    1997-01-01

    The leg vibrations of honeybees standing on a vibrating substrate were measured with laser Doppler vibrometry, both in freely standing bees and in bees attached to a holder. In both cases, no resonances were found. In the fixed bee preparation, the legs moved with approximately the same amplitude...

  13. Temperament and Attachment Disorders

    Science.gov (United States)

    Zeanah, Charles H.; Fox, Nathan A.

    2004-01-01

    Reviewed in this article is research on children with reactive attachment disorder (RAD) who exhibit specific patterns of socially aberrant behavior resulting from being maltreated or having limited opportunities to form selective attachments. There are no data explaining why 2 different patterns of the disorder, an emotionally withdrawn-inhibited…

  14. Attachment and Early Maltreatment.

    Science.gov (United States)

    Egeland, Byron; Sroufe, L. Alan

    1981-01-01

    Attachment outcomes of 31 maltreatment cases (involving extreme neglect or abuse), selected from a total poverty sample of 267 high-risk mothers and their children, were compared to those of a subsample of 33 cases with a history of excellent care. Attachment was assessed when infants were 12 and 18 months old. (Author/MP)

  15. Attachment Security and Pain

    DEFF Research Database (Denmark)

    Andersen, Tonny Elmose; Lahav, Yael; Defrin, Ruth;

    2015-01-01

    The present study assesses for the first time, the possible disruption effect of posttraumatic stress symptoms (PTSS) with regard to the protective role of attachment on pain, among ex-POWs. While secure attachment seems to serve as a buffer, decreasing the perception of pain, this function may...

  16. Mobile Probing and Probes

    DEFF Research Database (Denmark)

    Duvaa, Uffe; Ørngreen, Rikke; Weinkouff Mathiasen, Anne-Gitte;

    2013-01-01

    Mobile probing is a method, developed for learning about digital work situations, as an approach to discover new grounds. The method can be used when there is a need to know more about users and their work with certain tasks, but where users at the same time are distributed (in time and space...... to mobile probing being a flexible method for uncovering the unknowns, as a way of getting rich data to the analysis and design phases. On the other hand it is difficult to engage users to give in depth explanations, which seem easier in synchronous dialogs (whether online or face2face). The development...

  17. Mobile Probing and Probes

    DEFF Research Database (Denmark)

    Duvaa, Uffe; Ørngreen, Rikke; Weinkouff, Anne-Gitte;

    2012-01-01

    Mobile probing is a method, which has been developed for learning about digital work situations, as an approach to discover new grounds. The method can be used when there is a need to know more about users and their work with certain tasks, but where users at the same time are distributed (in time...... point to mobile probing being a flexible method for uncovering the unknowns, as a way of getting rich data to the analysis and design phases. On the other hand it is difficult to engage users to give in depth explanations, which seem easier in synchronous dialogs (whether online or face2face...

  18. Adolescent attachment and psychopathology.

    Science.gov (United States)

    Rosenstein, D S; Horowitz, H A

    1996-04-01

    The relationships among attachment classification, psychopathology, and personality traits were examined in a group of 60 psychiatrically hospitalized adolescents. The concordance of attachment classification was examined in 27 adolescent-mother pairs. Both adolescent and maternal attachment status were overwhelmingly insecure and were highly concordant. Adolescents showing a dismissing attachment organization were more likely to have a conduct or substance abuse disorder, narcissistic or antisocial personality disorder, and self-reported narcissistic, antisocial, and paranoid personality traits. Adolescents showing a preoccupied attachment organization were more likely to have an affective disorder, obsessive-compulsive, histrionic, borderline or schizotypal personality disorder, and self-reported avoidant, anxious, and dysthymic personality traits. The results support a model of development of psychopathology based partially on relational experiences with parents.

  19. Viscous-pendulum damper suppresses structural vibrations

    Science.gov (United States)

    Reed, W. H., III

    1964-01-01

    The viscous pendulum damper consists of a cylinder containing round trays on which round lead slugs rest. When assembled, the container is filled with a viscous liquid and attached, with axis vertical, to the structure. The device permits varying the damping of structural vibrations.

  20. Vibration sensors

    International Nuclear Information System (INIS)

    These sensors, which aim is the surveillance of the fast breeder reactor internal structure, were designed considering the following requirements: - long term utilization under low frequencies conditions (1 to 50 Hz) and detection of accelerations lower than 0,01 g, - operation with a temperature up to 6000C and receiving important neutron and gamma flux. Monoaxial sensors with a liquid vibrating mass (sodium) were thus developed, based on the electromagnetic flow meter principles (Faraday effect)

  1. Anisotropy of weakly vibrated granular flows.

    Science.gov (United States)

    Wortel, Geert H; van Hecke, Martin

    2015-10-01

    We experimentally probe the anisotropy of weakly vibrated flowing granular media. Depending on the driving parameters-flow rate and vibration strength-this anisotropy varies significantly. We show how the anisotropy collapses when plotted as a function of the driving stresses, uncovering a direct link between stresses and anisotropy. Moreover, our data suggest that for small anisotropies, the shear stresses vanish. Anisotropy of the fabric of granular media thus plays a crucial role in determining the rheology of granular flows. PMID:26565148

  2. Anisotropy of Weakly Vibrated Granular Flows

    OpenAIRE

    Wortel, Geert; Van Hecke, Martin

    2014-01-01

    We experimentally probe the anisotropy of the fabric of weakly vibrated, flowing granular media. Depending on the driving parameters --- flow rate and vibration strength --- this anisotropy varies significantly. We show how the anisotropy collapses when plotted as function of the driving stresses, uncovering a direct link between stresses and anisotropy. Moreover, our data suggests that for small anisotropies, the shear stresses vanish. Anisotropy of the fabric of granular media thus plays a ...

  3. Gerotor and bearing system for whirling mass orbital vibrator

    Science.gov (United States)

    Brett, James Ford; Westermark, Robert Victor; Turner, Jr., Joey Earl; Lovin, Samuel Scott; Cole, Jack Howard; Myers, Will

    2007-02-27

    A gerotor and bearing apparatus for a whirling mass orbital vibrator which generates vibration in a borehole. The apparatus includes a gerotor with an inner gear rotated by a shaft having one less lobe than an outer gear. A whirling mass is attached to the shaft. At least one bearing is attached to the shaft so that the bearing engages at least one sleeve. A mechanism is provided to rotate the inner gear, the mass and the bearing in a selected rotational direction in order to cause the mass, the inner gear, and the bearing to backwards whirl in an opposite rotational direction. The backwards whirling mass creates seismic vibrations.

  4. Attachment-related psychodynamics.

    Science.gov (United States)

    Shaver, Phillip R; Mikulincer, Mario

    2002-09-01

    Because there has been relatively little communication and cross-fertilization between the two major lines of research on adult attachment, one based on coded narrative assessments of defensive processes, the other on simple self-reports of 'attachment style' in close relationships, we here explain and review recent work based on a combination of self-report and other kinds of method, including behavioral observations and unconscious priming techniques. The review indicates that considerable progress has been made in testing central hypotheses derived from attachment theory and in exploring unconscious, psychodynamic processes related to affect-regulation and attachment-system activation. The combination of self-report assessment of attachment style and experimental manipulation of other theoretically pertinent variables allows researchers to test causal hypotheses. We present a model of normative and individual-difference processes related to attachment and identify areas in which further research is needed and likely to be successful. One long-range goal is to create a more complete theory of personality built on attachment theory and other object relations theories.

  5. The neurobiology of attachment.

    Science.gov (United States)

    Insel, T R; Young, L J

    2001-02-01

    It is difficult to think of any behavioural process that is more intrinsically important to us than attachment. Feeding, sleeping and locomotion are all necessary for survival, but humans are, as Baruch Spinoza famously noted, "a social animal" and it is our social attachments that we live for. Over the past decade, studies in a range of vertebrates, including humans, have begun to address the neural basis of attachment at a molecular, cellular and systems level. This review describes some of the important insights from this work.

  6. Multidimensional time-resolved spectroscopy of vibrational coherence in biopolyenes.

    Science.gov (United States)

    Buckup, Tiago; Motzkus, Marcus

    2014-01-01

    Multidimensional femtosecond time-resolved vibrational coherence spectroscopy allows one to investigate the evolution of vibrational coherence in electronic excited states. Methods such as pump-degenerate four-wave mixing and pump-impulsive vibrational spectroscopy combine an initial ultrashort laser pulse with a nonlinear probing sequence to reinduce vibrational coherence exclusively in the excited states. By carefully exploiting specific electronic resonances, one can detect vibrational coherence from 0 cm(-1) to over 2,000 cm(-1) and map its evolution. This review focuses on the observation and mapping of high-frequency vibrational coherence for all-trans biological polyenes such as β-carotene, lycopene, retinal, and retinal Schiff base. We discuss the role of molecular symmetry in vibrational coherence activity in the S1 electronic state and the interplay of coupling between electronic states and vibrational coherence.

  7. EMBEDDED COMPUTER BASED ACTIVE VIBRATION CONTROL SYSTEM FOR VIBRATION REDUCTION OF FLEXIBLE STRUCTURES

    Directory of Open Access Journals (Sweden)

    Venkata Ratnam Tatavolu

    2013-01-01

    Full Text Available Research on Active Vibration Control System (AVCS is being carried out to reduce structural vibrations caused by unwanted vibrations in many application areas such as in space, aircraft structures, satellites, automobiles and civil structures (bridges, particularly at low frequencies. The unwanted vibration may cause damage to the structure or degradation to the structure’s performance. The AVCS comprises physical plant, a sensor to detect the source vibration, a DSP based electronic controller using an actuator connected to the structure generates a counter force that is appropriately out of phase but equal in amplitude to the source vibration. As a result two equal and opposite forces cancel each other by the principle of super position and structure stops vibrating. The main objective of this research work is to develop an embedded computer based real time AVCS for reducing low frequency tonal vibration response of a vibrating flexible cantilever beam by automatic modification of the vibrating beam’s structural response and to verify the performance of the developed system experimentally. The developed AVCS is a generic design platform that can be applied for designing adaptive feed forward AVC and feedback AVC. This study presents the vibration control methodology adapted for reducing tonal vibration generated by a sine generator connected to the primary source actuator attached to one end of the cantilever beam. The secondary actuator is attached to the beam on the other end through the AVCS to reduce primary vibration by destructive interference with the original response of the system, caused by the primary source of vibration. Adaptive feed forward Active Vibration Control (AVC technique is used with Filtered-X Least Mean Square (FxLMS algorithm using FIR digital filter. A cantilever beam was considered as plant and embedded computer based AVCS was tested and evaluated using an experimental setup. The experimental results are

  8. Attachment and Psychotherapy

    OpenAIRE

    McKay, J.M.

    2010-01-01

    The aim of this study was to explore the relationship between therapy outcome, the therapeutic alliance and both patient and therapist attachment styles. 14 therapists and 27 patients participated. 78.57% (n = 11) therapists and 29.63% (n = 8) patients were classified as securely attached by self-report measures. It was predicted that more patients of secure therapists would show clinically significant improvement as determined by CORE-OM scores. However, 21.05% of patients with a secure atta...

  9. Propellant grain dynamics in aft attach ring of shuttle solid rocket booster

    Science.gov (United States)

    Verderaime, V.

    1979-01-01

    An analytical technique for implementing simultaneously the temperature, dynamic strain, real modulus, and frequency properties of solid propellant in an unsymmetrical vibrating ring mode is presented. All dynamic parameters and sources are defined for a free vibrating ring-grain structure with initial displacement and related to a forced vibrating system to determine the change in real modulus. Propellant test data application is discussed. The technique was developed to determine the aft attach ring stiffness of the shuttle booster at lift-off.

  10. Linear and nonlinear piezoelectric shunting strategies for vibration mitigation

    Directory of Open Access Journals (Sweden)

    Soltani P.

    2014-01-01

    Full Text Available This paper studies linear and nonlinear piezoelectric vibration absorbers that are designed based on the equal-peak method. A comparison between the performance of linear mechanical and electrical tuned vibration absorbers coupled to a linear oscillator is first performed. Nonlinearity is then introduced in the primary oscillator to which a new nonlinear electrical tuned vibration absorber is attached. Despite the frequency-energy dependence of nonlinear oscillations, we show that the nonlinear absorber is capable of effectively mitigating the vibrations of the nonlinear primary system in a large range of forcing amplitudes.

  11. Wideband Piezomagnetoelastic Vibration Energy Harvesting

    DEFF Research Database (Denmark)

    Lei, Anders; Thomsen, Erik Vilain

    2014-01-01

    This work presents a small-scale wideband piezomagnetoelastic vibration energy harvester (VEH) aimed for operation at frequencies of a few hundred Hz. The VEH consists of a tape-casted PZT cantilever with thin sheets of iron foil attached on each side of the free tip. The wideband operation...... is achieved by placing the cantilever in a magnetic field induced by either one or two magnets located oppositely of the cantilever. The attraction force created by the magnetic field and iron foils introduces a mechanical force in opposite direction of the cantilevers restoring force causing a spring...

  12. Attachment and coercive sexual behavior.

    Science.gov (United States)

    Smallbone, S W; Dadds, M R

    2000-01-01

    This study examined the relationships between childhood attachment and coercive sexual behavior. One hundred sixty-two male undergraduate students completed self-report measures of childhood maternal attachment, childhood paternal attachment, adult attachment, antisociality, aggression, and coercive sexual behavior. As predicted, insecure childhood attachment, especially insecure paternal attachment, was associated with antisociality, aggression, and coercive sexual behavior. Moreover, childhood attachment independently predicted coercive sexual behavior after antisociality and aggression were statistically controlled. The hypothesis that paternal avoidant attachment would predict coercive sexual behavior independently of its relationship with aggression and antisociality was also supported. Posthoc analysis indicated that maternal anxious attachment was associated with antisociality and that paternal avoidant attachment was associated with both antisociality and coercive sexual behavior. These results are consistent with criminological and psychological research linking adverse early family experiences with offending and lend support to an attachment-theoretical framework for understanding offending behavior in general and sexual offending behavior in particular.

  13. Ladder attachment platform

    Science.gov (United States)

    Swygert,; Richard, W [Springfield, SC

    2012-08-28

    A ladder attachment platform is provided that includes a base for attachment to a ladder that has first and second side rails and a plurality of rungs that extend between in a lateral direction. Also included is a user platform for having a user stand thereon that is carried by the base. The user platform may be positioned with respect to the ladder so that it is not located between a first plane that extends through the first side rail and is perpendicular to the lateral direction and a second plane that extends through the second side rail and is perpendicular to the lateral direction.

  14. Theory of vibration protection

    CERN Document Server

    Karnovsky, Igor A

    2016-01-01

    This text is an advancement of the theory of vibration protection of mechanical systems with lumped and distributed parameters. The book offers various concepts and methods of solving vibration protection problems, discusses the advantages and disadvantages of different methods, and the fields of their effective applications. Fundamental approaches of vibration protection, which are considered in this book, are the passive, parametric and optimal active vibration protection. The passive vibration protection is based on vibration isolation, vibration damping and dynamic absorbers. Parametric vibration protection theory is based on the Shchipanov-Luzin invariance principle. Optimal active vibration protection theory is based on the Pontryagin principle and the Krein moment method. The book also contains special topics such as suppression of vibrations at the source of their occurrence and the harmful influence of vibrations on humans. Numerous examples, which illustrate the theoretical ideas of each chapter, ar...

  15. MOWER ATTACHMENT NOISE

    OpenAIRE

    Mosdzianowski, G.

    1990-01-01

    The noise produced by grass mowing attachments fitted to small tractors and combining a number of rotary blades with a total cutting width of up to 120 cm was investigated. The paper develops a noise reduction concept based on an analysis of sound sources.

  16. Attachment and Personality Disorders

    Science.gov (United States)

    Sinha, Preeti; Sharan, Pratap

    2007-01-01

    Personality disorders (PDs) arise from core psychopathology of interpersonal relationships and understanding of self and others. The distorted representations of self and others, as well as unhealthy relationships that characterize persons with various PDs, indicate the possibility that persons with PDs have insecure attachment. Insecure…

  17. Picturing Urban Green Attachments

    DEFF Research Database (Denmark)

    Blok, Anders; Meilvang, Marie Leth

    2015-01-01

    In this article, we explore the cultural-political tensions and ambiguities of urban ecology, by way of following how activists move and translate between ‘familiar’ and ‘public’ engagements in the green city. Empirically, we locate our exploration in and around Nordhavnen (The North Harbor...... in the plural’ in the city. In particular, we stress the role assumed in such engagements by various image-making practices, as means for activists to express, share and render publicly visible a range of embodied urban attachments. Pragmatic sociology, we conclude, may contribute to a novel understanding...... of urban politics as inclusive learning processes, more hospitable to a wider diversity of familiar attachments to cities and their ecologies....

  18. Turbine nozzle attachment system

    Science.gov (United States)

    Norton, Paul F.; Shaffer, James E.

    1995-01-01

    A nozzle guide vane assembly having a preestablished rate of thermal expansion is positioned in a gas turbine engine and being attached to conventional metallic components. The nozzle guide vane assembly includes a pair of legs extending radially outwardly from an outer shroud and a pair of mounting legs extending radially inwardly from an inner shroud. Each of the pair of legs and mounting legs have a pair of holes therein. A plurality of members attached to the gas turbine engine have a plurality of bores therein which axially align with corresponding ones of the pair of holes in the legs. A plurality of pins are positioned within the corresponding holes and bores radially positioning the nozzle guide vane assembly about a central axis of the gas turbine engine.

  19. Two-dimensional vibrational-electronic spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Courtney, Trevor L.; Fox, Zachary W.; Slenkamp, Karla M.; Khalil, Munira, E-mail: mkhalil@uw.edu [Department of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195 (United States)

    2015-10-21

    Two-dimensional vibrational-electronic (2D VE) spectroscopy is a femtosecond Fourier transform (FT) third-order nonlinear technique that creates a link between existing 2D FT spectroscopies in the vibrational and electronic regions of the spectrum. 2D VE spectroscopy enables a direct measurement of infrared (IR) and electronic dipole moment cross terms by utilizing mid-IR pump and optical probe fields that are resonant with vibrational and electronic transitions, respectively, in a sample of interest. We detail this newly developed 2D VE spectroscopy experiment and outline the information contained in a 2D VE spectrum. We then use this technique and its single-pump counterpart (1D VE) to probe the vibrational-electronic couplings between high frequency cyanide stretching vibrations (ν{sub CN}) and either a ligand-to-metal charge transfer transition ([Fe{sup III}(CN){sub 6}]{sup 3−} dissolved in formamide) or a metal-to-metal charge transfer (MMCT) transition ([(CN){sub 5}Fe{sup II}CNRu{sup III}(NH{sub 3}){sub 5}]{sup −} dissolved in formamide). The 2D VE spectra of both molecules reveal peaks resulting from coupled high- and low-frequency vibrational modes to the charge transfer transition. The time-evolving amplitudes and positions of the peaks in the 2D VE spectra report on coherent and incoherent vibrational energy transfer dynamics among the coupled vibrational modes and the charge transfer transition. The selectivity of 2D VE spectroscopy to vibronic processes is evidenced from the selective coupling of specific ν{sub CN} modes to the MMCT transition in the mixed valence complex. The lineshapes in 2D VE spectra report on the correlation of the frequency fluctuations between the coupled vibrational and electronic frequencies in the mixed valence complex which has a time scale of 1 ps. The details and results of this study confirm the versatility of 2D VE spectroscopy and its applicability to probe how vibrations modulate charge and energy transfer in a

  20. Universally Rigid Framework Attachments

    CERN Document Server

    Ratmanski, Kiril

    2010-01-01

    A framework is a graph and a map from its vertices to R^d. A framework is called universally rigid if there is no other framework with the same graph and edge lengths in R^d' for any d'. A framework attachment is a framework constructed by joining two frameworks on a subset of vertices. We consider an attachment of two universally rigid frameworks that are in general position in R^d. We show that the number of vertices in the overlap between the two frameworks must be sufficiently large in order for the attachment to remain universally rigid. Furthermore, it is shown that universal rigidity of such frameworks is preserved even after removing certain edges. Given positive semidefinite stress matrices for each of the two initial frameworks, we analytically derive the PSD stress matrices for the combined and edge-reduced frameworks. One of the benefits of the results is that they provide a general method for generating new universally rigid frameworks.

  1. Attachment disorganization in different clinical groups: What underpins unresolved attachment?

    OpenAIRE

    Juen Florian; Arnold Lisa; Meissner Dominik; Nolte Tobias; Buchheim Anna

    2013-01-01

    This paper summarizes findings and clinical implications of research on attachment disorganization in diverse clinical groups. Disorganized/unresolved attachment is overrepresented in these groups compared to healthy control participants, but disorder specific characteristics of this attachment pattern are still poorly understood. The focus of this study was to explore defensive processes in participants whose narratives were classified as disorganized/unresolved using the Adult Attach...

  2. Behavior of Cell on Vibrating Micro Ridges

    Directory of Open Access Journals (Sweden)

    Haruka Hino

    2015-06-01

    Full Text Available The effect of micro ridges on cells cultured at a vibrating scaffold has been studied in vitro. Several parallel lines of micro ridges have been made on a disk of transparent polydimethylsiloxane for a scaffold. To apply the vibration on the cultured cells, a piezoelectric element was attached on the outside surface of the bottom of the scaffold. The piezoelectric element was vibrated by the sinusoidal alternating voltage (Vp-p < 16 V at 1.0 MHz generated by a function generator. Four kinds of cells were used in the test: L929 (fibroblast connective tissue of C3H mouse, Hepa1-6 (mouse hepatoma, C2C12 (mouse myoblast, 3T3-L1 (mouse fat precursor cells. The cells were seeded on the micro pattern at the density of 2000 cells/cm2 in the medium containing 10% FBS (fetal bovine serum and 1% penicillin/ streptomycin. After the adhesion of cells in several hours, the cells are exposed to the ultrasonic vibration for several hours. The cells were observed with a phase contrast microscope. The experimental results show that the cells adhere, deform and migrate on the scaffold with micro patterns regardless of the ultrasonic vibration. The effects of the vibration and the micro pattern depend on the kind of cells.

  3. Probing halo molecules with nonresonant light

    CERN Document Server

    Lemeshko, Mikhail

    2009-01-01

    We show that halo molecules can be probed by "shaking" in a pulsed nonresonant laser field. The field introduces a centrifugal term which expels the highest vibrational level from the potential that binds it. Our numerical simulations as well as an analytic model applied to the Rb$_2$ and KRb Feshbach molecules indicate that shaking by feasible laser pulses can be used to accurately recover the square of the vibrational wavefunction and, by inversion, also the molecular potential.

  4. Positron-molecule interactions: resonant attachment, annihilation, and bound states

    CERN Document Server

    Gribakin, G F; Surko, C M; 10.1103/RevModPhys.82.2557

    2010-01-01

    This article presents an overview of current understanding of the interaction of low-energy positrons with molecules with emphasis on resonances, positron attachment and annihilation. Annihilation rates measured as a function of positron energy reveal the presence of vibrational Feshbach resonances (VFR) for many polyatomic molecules. These resonances lead to strong enhancement of the annihilation rates. They also provide evidence that positrons bind to many molecular species. A quantitative theory of VFR-mediated attachment to small molecules is presented. It is tested successfully for selected molecules (e.g., methyl halides and methanol) where all modes couple to the positron continuum. Combination and overtone resonances are observed and their role is elucidated. In larger molecules, annihilation rates from VFR far exceed those explicable on the basis of single-mode resonances. These enhancements increase rapidly with the number of vibrational degrees of freedom. While the details are as yet unclear, intr...

  5. Attachment as an Organizational Construct

    Science.gov (United States)

    Sroufe, L. Alan; Waters, Everett

    1977-01-01

    Discusses the conflict between situational influences and stable individual differences in attachment behavior and attempts to resolve this conflict by examining the functions, outcomes, and context sensitivity of attachment behavior and the underlying behavioral control systems that organize it. (JMB)

  6. Mechanical vibration to electrical energy converter

    Science.gov (United States)

    Kellogg, Rick Allen; Brotz, Jay Kristoffer

    2009-03-03

    Electromechanical devices that generate an electrical signal in response to an external source of mechanical vibrations can operate as a sensor of vibrations and as an energy harvester for converting mechanical vibration to electrical energy. The devices incorporate a magnet that is movable through a gap in a ferromagnetic circuit, wherein a coil is wound around a portion of the ferromagnetic circuit. A flexible coupling is used to attach the magnet to a frame for providing alignment of the magnet as it moves or oscillates through the gap in the ferromagnetic circuit. The motion of the magnet can be constrained to occur within a substantially linear range of magnetostatic force that develops due to the motion of the magnet. The devices can have ferromagnetic circuits with multiple arms, an array of magnets having alternating polarity and, encompass micro-electromechanical (MEM) devices.

  7. DEMONSTRATION OF MULTIPLE ANTIGENIC DETERMINANTS ON 'MYCOPLASMA PNEUMONIAE' ATTACHMENT PROTEIN BY MONOCLONAL ANTIBODIES

    Science.gov (United States)

    Distinct multiple antigenic determinants of the attachment protein of Mycoplasma pneumoniae have been identified by limited proteolytic cleavage using specific monoclonal antibodies. Western blots prepared from the gels containing the cleaved fragments were probed with antiserum ...

  8. Fast and reliable method of conductive carbon nanotube-probe fabrication for scanning probe microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Dremov, Vyacheslav, E-mail: dremov@issp.ac.ru; Fedorov, Pavel; Grebenko, Artem [Institute of Solid State Physics, RAS, 142432 Chernogolovka (Russian Federation); Interdisciplinary Center for Basic Research, Moscow Institute of Physics and Technology, 141700 Dolgoprudniy (Russian Federation); Fedoseev, Vitaly [Institute of Solid State Physics, RAS, 142432 Chernogolovka (Russian Federation)

    2015-05-15

    We demonstrate the procedure of scanning probe microscopy (SPM) conductive probe fabrication with a single multi-walled carbon nanotube (MWNT) on a silicon cantilever pyramid. The nanotube bundle reliably attached to the metal-covered pyramid is formed using dielectrophoresis technique from the MWNT suspension. It is shown that the dimpled aluminum sample can be used both for shortening/modification of the nanotube bundle by applying pulse voltage between the probe and the sample and for controlling the probe shape via atomic force microscopy imaging the sample. Carbon nanotube attached to cantilever covered with noble metal is suitable for SPM imaging in such modulation regimes as capacitance contrast microscopy, Kelvin probe microscopy, and scanning gate microscopy. The majority of such probes are conductive with conductivity not degrading within hours of SPM imaging.

  9. Structural Vibration Control Using Solid Particle Damper

    Directory of Open Access Journals (Sweden)

    Haseena. A

    2015-11-01

    Full Text Available In this paper the effectiveness of a solid particle damper to control structural vibration is experimentally investigated. The vibration control performance and its influencing parameters are examined by a Multi Degree of Freedom (MDOF structure attached with a particle damper (PD under horizontal excitation. In a particle damping system damping is achieved using solid particles or granules and is a passive damping method. Here the enclosure filled with particles is attached to the primary structure undergoing vibration. As the primary structure vibrates, particles undergo inelastic collision within the enclosure resulting high amount of energy dissipation. Based on the analytical study of undamped frame in ANSYS WORKBENCH, dimensions of the frame were fixed and shake table study of a two storied steel frame with and without damper system are carried out. Results shows that effectiveness of damping depends on various parameters like mass, particle size, shape etc. The effectiveness is compared with a friction damper (FD and is observed that PD is more efficient than FD since 31.80% energy is dissipated more in PD compared to FD

  10. Attachment Behaviors in Autistic Children.

    Science.gov (United States)

    Sigman, Marian; Ungerer, Judy A.

    1984-01-01

    Observation of 14 autistic and 14 nonautistic children of equivalent mental age revealed that autistic Ss showed evidence of attachment to their mothers. Among autistic Ss, those showing increased attachment behaviors in response to separation and reunion demonstrated more advanced symbolic play skills than those showing no attachment change.…

  11. Attachment Theory: Retrospect and Prospect.

    Science.gov (United States)

    Bretherton, Inge

    1985-01-01

    Provides overview of attachment theory as parented by John Bowlby in "Attachment and Loss". Uses two major concepts from this work to interpret refinements and elaborations of attachment theory attibuted to Mary Ainsworth. Considers how recent insights into development of socioemotional understanding and development of event representation can be…

  12. Anharmonic Vibrational Dynamics of DNA Oligomers

    CERN Document Server

    Kühn, O; Krishnan, G M; Fidder, H; Heyne, K

    2008-01-01

    Combining two-color infared pump-probe spectroscopy and anharmonic force field calculations we characterize the anharmonic coupling patterns between fingerprint modes and the hydrogen-bonded symmetric NH$_2$ stretching vibration in adenine-thymine dA$_{20}$-dT$_{20}$ DNA oligomers. Specifically, it is shown that the anharmonic coupling between the NH$_2$ bending and the CO stretching vibration, both absorbing around 1665 cm-1, can be used to assign the NH$_2$ fundamental transition at 3215 cm-1 despite the broad background absorption of water.

  13. Probe Storage

    NARCIS (Netherlands)

    Gemelli, Marcellino; Abelmann, Leon; Engelen, Johan B.C.; Khatib, Mohammed G.; Koelmans, Wabe W.; Zaboronski, Olog; Campardo, Giovanni; Tiziani, Federico; Laculo, Massimo

    2011-01-01

    This chapter gives an overview of probe-based data storage research over the last three decades, encompassing all aspects of a probe recording system. Following the division found in all mechanically addressed storage systems, the different subsystems (media, read/write heads, positioning, data chan

  14. Vibrations and Stability

    DEFF Research Database (Denmark)

    Thomsen, Jon Juel

    and physics. This edition includes a new chapter on the useful effects of fast vibrations and many new exercise problems. Written for: Students in mechanical or structural engineering. Keywords: Nonlinear Vibrations, Bifurcations, Chaotic Vibrations, Vibrations and Stability.......About this textbook An ideal text for students that ties together classical and modern topics of advanced vibration analysis in an interesting and lucid manner. It provides students with a background in elementary vibrations with the tools necessary for understanding and analyzing more complex...... dynamical phenomena that can be encountered in engineering and scientific practice. It progresses steadily from linear vibration theory over various levels of nonlinearity to bifurcation analysis, global dynamics and chaotic vibrations. It trains the student to analyze simple models, recognize nonlinear...

  15. ACTIVE VIBRATION SUPPRESSION VIA LINEARIZING HYSTERESIS OF PIEZOCERAMIC ACTUATORS

    Institute of Scientific and Technical Information of China (English)

    HU Hong; SHI Hongyan; BEN MRAD Ridha

    2007-01-01

    A novel active Vibration control technique on the basis of linearized piezoelectric actuators is presented. An experimental apparatus consisting of a cantilever beam to which are attached strain patches and piezoceramic actuators to be used for active Vibration suppression is described. A dynamical model of the cantilever beam using Lagrange's equation and two coordinate Systems are presented. Based on the Lyapunov's direct method, an active Vibration Controller with hysteresis compensation is designed. The Controller is designed so that it guarantees the global stability of the overall System. The Controller developed is assessed experimentally.

  16. Attachment Theory in Tourism

    Directory of Open Access Journals (Sweden)

    Maximiliano Korstanje

    2007-01-01

    Full Text Available The following work is intended to a revision on attachment theory. The postulates of the theory of the sure base point that the system of exploration meets in narrow relation the system of conducts of attachment and the figure of the keepers. The conducts that characterize and symbolize the relation of the adult with the environment are carried back to the early age, in the moment in which the child develops the affective capacity. What difference does exist between someone who decides to journey to England and that one that one decides to travel to Mar del Plata? How it is possible to study this topic of on a manner trustworthy? These three questions were key to begin the investigation. Nevertheless, the matter began to find certain limitations linked to the methodology that had to be in use. It is possible to use careless they on the leisure scope, a theory which still demonstrates certain inconsistencies in its own clinical application?

  17. Attachment is a dynamic system

    Directory of Open Access Journals (Sweden)

    Zlatka Cugmas

    2003-04-01

    Full Text Available On the basis of the study of recent scientific literature about the development of attachment, the author answers the following questions: which are the postulates the theory of attachment has about the stability of the patterns of attachment, which level of stability in the patterns of attachment from infancy to adulthood these studies illuminate and which factors significantly influence the (instability of the patterns of attachment in time. The theory of attachment assumes that normal circumstances elicit stability. Changes, however, can be the result of important events influencing the sensitivity of the object of attachment. Agreement has not yet been reached regarding the percentage of stability in the patterns of attachment. There is more agreement regarding attachment in adulthood than that in childhood. The results depend on the size and characteristics of the subjects of the research, the measuring instruments, type of data analysis etc. The author concludes that attachment is a dynamic system influenced by significant changes in life (the cognitive development of the child, external care, parents' divorce, different stressful situations. As the influence of stressful events on the individual person' s quality of attachment is examined, it is necessary to consider also his/her temperamental characteristics, role of other people in their lives, etc.

  18. Mapping and measuring place attachment

    DEFF Research Database (Denmark)

    Brown, Greg; Raymond, Christopher Mark; Corcoran, Jonathan

    2015-01-01

    ) identify how participant socio-demographic and home location attributes influence place attachment, (4) provide some guidance for mapping place attachment in future research. We found large spatial variability in individual place attachment and mapped landscape values using both area and distance......-based measures. The area of place attachment is influenced by occupational roles such as farming or conservation, as well as home location, especially in coastal versus non-coastal contexts. The spatial distribution of mapped landscape values or values home range is related to, but not identical to mapped place...... attachment with just over half of landscape values located outside the area of mapped place attachment. Economic livelihood values, as an indicator of place dependence, and social values, as an indicator of place identity, are more likely to be mapped within the place attachment area. Aggregated place...

  19. Vibration of plates

    CERN Document Server

    Chakraverty, Snehashish

    2008-01-01

    Plates are integral parts of most engineering structures and their vibration analysis is required for safe design. This work provides a comprehensive introduction to vibration theory and analysis of two-dimensional plates. It offers information on vibration problems along with a discussion of various plate geometries and boundary conditions.

  20. Autoparametric vibrations of a nonlinear system with pendulum

    Directory of Open Access Journals (Sweden)

    2006-01-01

    Full Text Available Vibrations of a nonlinear oscillator with an attached pendulum, excited by movement of its point of suspension, have been analysed in the paper. The derived differential equations of motion show that the system is strongly nonlinear and the motions of both subsystems, the pendulum and the oscillator, are strongly coupled by inertial terms, leading to the so-called autoparametric vibrations. It has been found that the motion of the oscillator, forced by an external harmonic force, has been dynamically eliminated by the pendulum oscillations. Influence of a nonlinear spring on the vibration absorption near the main parametric resonance region has been carried out analytically, whereas the transition from regular to chaotic vibrations has been presented by using numerical methods. A transmission force on the foundation for regular and chaotic vibrations is presented as well.

  1. Vibration of hydraulic machinery

    CERN Document Server

    Wu, Yulin; Liu, Shuhong; Dou, Hua-Shu; Qian, Zhongdong

    2013-01-01

    Vibration of Hydraulic Machinery deals with the vibration problem which has significant influence on the safety and reliable operation of hydraulic machinery. It provides new achievements and the latest developments in these areas, even in the basic areas of this subject. The present book covers the fundamentals of mechanical vibration and rotordynamics as well as their main numerical models and analysis methods for the vibration prediction. The mechanical and hydraulic excitations to the vibration are analyzed, and the pressure fluctuations induced by the unsteady turbulent flow is predicted in order to obtain the unsteady loads. This book also discusses the loads, constraint conditions and the elastic and damping characters of the mechanical system, the structure dynamic analysis, the rotor dynamic analysis and the system instability of hydraulic machines, including the illustration of monitoring system for the instability and the vibration in hydraulic units. All the problems are necessary for vibration pr...

  2. Theoretical and experimental study of the dynamic response of absorber-based, micro-scale, oscillatory probes for contact sensing applications

    Science.gov (United States)

    Kafashi, Sajad; Strayhorn, Ralph; Eldredge, Jeff D.; Kelly, Scott D.; Woody, Shane C.; Smith, Stuart T.

    2016-06-01

    This paper presents two models for predicting the frequency response of micro-scale oscillatory probes. These probes are manufactured by attaching a thin fiber to the free end of one tine of a quartz tuning fork oscillator. In these studies, the attached fibers were either 75 μm diameter tungsten or 7 μm diameter carbon with lengths ranging from around 1 to 15 mm. The oscillators used in these studies were commercial 32.7 kHz quartz tuning forks. The first theoretical model considers lateral vibration of two beams serially connected and provides a characteristic equation from which the roots (eigenvalues) are extracted to determine the natural frequencies of the probe. A second, lumped model approximation is used to derive an approximate frequency response function for prediction of tine displacements as a function of a modal force excitation corresponding to the first mode of the tine in the absence of a fiber. These models are used to evaluate the effect of changes in both length and diameter of the attached fibers. Theoretical values of the natural frequencies of different modes show an asymptotic relationship with the length and a linear relationship with the diameter of the attached fiber. Similar results are observed from experiment, one with a tungsten probe having an initial fiber length of 14.11 mm incrementally etched down to 0.83 mm, and another tungsten probe of length 8.16 mm incrementally etched in diameter, in both cases using chronocoulometry to determine incremental volumetric material removal. The lumped model is used to provide a frequency response again reveals poles and zeros that are consistent with experimental measurements. Finite element analysis shows mode shapes similar to experimental microscope observations of the resonating carbon probes. This model provides a means of interpreting measured responses in terms of the relative motion of the tine and attached fibers. Of particular relevance is that, when a "zero" is observed in the

  3. Borderline disorder and attachment pathology.

    Science.gov (United States)

    West, M; Keller, A; Links, P; Patrick, J

    1993-02-01

    In this paper, the authors investigate the theoretical and empirical association between dysfunctions of the attachment system and borderline personality disorder. Attachment theory focuses on the maintenance of a sense of safety and security through a close personal relationship with a particular person. Based on a biological behavioural system, functional attachment relationships in adulthood rely on experiences and expectations of security within the relationship. These issues are also important to the definition and dynamics of borderline personality disorder. The dimensions and patterns of reciprocal attachment were compared with other scales measuring components of psychopathology and interpersonal relationships. In a sample of 85 female outpatients, only four of the attachment scales--feared loss, secure base, compulsive care-seeking and angry withdrawal--identified patients with high scores on a measure of borderline disorder. Of these four scales, feared loss had the predominant effect. These empirical results support the hypothesized relationship between dysfunctions of the attachment system and borderline disorder.

  4. Attachment theory: Old and new approach

    OpenAIRE

    Polovina Nada

    2005-01-01

    The article is an attempt to present holistically the key concepts of attachment theory rediscovered for its potentials. The presented concepts include: narrow definition of attachment, behavioral control system of attachment, attachment working model and patterns of attachment. The concepts are presented in the context of child attachment theory and adult attachment theory, in addition to description of the development of attachment. Concepts, as well as developmental processes are presented...

  5. A 4 K cryogenic probe for use in magnetic resonance force microscopy experiments

    Science.gov (United States)

    Smith, Doran D.; Alexson, Dimitri A.; Garbini, Joseph L.

    2013-09-01

    The detailed design of a mechanically detected nuclear magnetic resonance probe using the SPAM (Springiness Preservation by Aligning Magnetization) geometry, operating at 4 K, in vacuum, and a several-Tesla magnetic field is described. The probe head is vibration-isolated well enough from the environment by a three-spring suspension system that the cantilever achieves thermal equilibrium with the environment without the aid of eddy current damping. The probe uses an ultra-soft Si cantilever with a Ni sphere attached to its tip, and magnetic resonance is registered as a change in the resonant frequency of the driven cantilever. The RF system uses frequency sweeps for adiabatic rapid passage using a 500 μm diameter RF coil wound around a sapphire rod. The RF coil and optical fiber of the interferometer used to sense the cantilever's position are both located with respect to the cantilever using a Garbini micropositioner, and the sample stage is mounted on an Attocube nanopositioner.

  6. Attachment theory and therapeutic relationships

    OpenAIRE

    Boysan, Zehra

    2015-01-01

    The aims of this study were to examine the associations between current self-reported attachment styles, retrospective reports of childhood experiences, and the development of the therapeutic alliance. It was hypothesised that anxious and avoidant attachment would be correlated with negative childhood experiences and that both attachment anxiety and avoidance would be inversely correlated with the therapeutic alliance. The third hypothesis stated that negative childhood recollections would co...

  7. Adult attachment and psychosocial functioning

    OpenAIRE

    Pielage, Suzanne Brenda

    2006-01-01

    In the trilogy Attachment, Separation and Loss (1969, 1973, 1980), Bowlby theorized that early experiences with caregivers affect the quality of individuals’ later (romantic) relationships and, consequently, their mental health. The current thesis set out to examine the relationships between adult attachment and psychosocial functioning, predominately in the realm of close relationships. In the first part of the thesis, the focus lay on the assessment of the adult attachment construct. In Cha...

  8. Vibration compensating beam scanning interferometer for surface measurement

    OpenAIRE

    Jiang, Xiang; Martin, Haydn; Wang, Kaiwei

    2007-01-01

    Light beam scanning using a dispersive element and wavelength tuning is coupled with fibre-optic interferometry to realize a new surface measurement instrument. The instrument is capable of measuring nano-scale surface structures and form deviation. It features active vibration compensation and a small optical probe size that may be placed remotely from the main apparatus. Active vibration compensation is provided by the multiplexing of two interferometers with near common paths. Closed loop ...

  9. Attachment disorganization in different clinical groups: What underpins unresolved attachment?

    Directory of Open Access Journals (Sweden)

    Juen Florian

    2013-01-01

    Full Text Available This paper summarizes findings and clinical implications of research on attachment disorganization in diverse clinical groups. Disorganized/unresolved attachment is overrepresented in these groups compared to healthy control participants, but disorder specific characteristics of this attachment pattern are still poorly understood. The focus of this study was to explore defensive processes in participants whose narratives were classified as disorganized/unresolved using the Adult Attachment Projective Picture System (AAP. Besides the predominance of disorganized attachment, clinical participants demonstrated more “segregated system material” especially in stories representing aloneness and more “Personal Experience material” compared to healthy individuals. Within the disorganized/ unresolved clinical individuals, BPD and PTSD patients showed the highest proportion of attachment disorganization and were less able to use other attachment-related defenses to maintain organized. Furthermore, PTSD patients were emotionally overwhelmed by the projective attachment scenes compared to the other clinical groups as indexed by an incapacity to complete sections of the AAP. BPD and addicted patients were characterized by a high degree of self-other boundary confusion. Depressive and schizophrenic patients showed a high overall defensive intensity to remain organized.

  10. Parallel scanning probe arrays: their applications

    Directory of Open Access Journals (Sweden)

    Chang Liu

    2008-01-01

    Full Text Available Since the invention of the scanning tunneling microscope (STM1 and the atomic force microscope (AFM2, the field of scanning probe microscopy (SPM instruments has grown steadily and has had a profound influence in materials research, chemistry, biology, nanotechnology, and electronics3,4. Today, scanning probe instruments are used for metrology, characterization5, detection6, manipulation7, patterning8,9, and material modification. A wide range of scanning probe applications are available, taking advantage of various modes of tip–substrate interactions, including force, optics10,11, electrochemistry12, electromagnetics, electrostatics, thermal and mass transfer13,14, and vibration15,16.

  11. Probing Capacity

    CERN Document Server

    Asnani, Himanshu; Weissman, Tsachy

    2010-01-01

    We consider the problem of optimal probing of states of a channel by transmitter and receiver for maximizing rate of reliable communication. The channel is discrete memoryless (DMC) with i.i.d. states. The encoder takes probing actions dependent on the message. It then uses the state information obtained from probing causally or non-causally to generate channel input symbols. The decoder may also take channel probing actions as a function of the observed channel output and use the channel state information thus acquired, along with the channel output, to estimate the message. We refer to the maximum achievable rate for reliable communication for such systems as the 'Probing Capacity'. We characterize this capacity when the encoder and decoder actions are cost constrained. To motivate the problem, we begin by characterizing the trade-off between the capacity and fraction of channel states the encoder is allowed to observe, while the decoder is aware of channel states. In this setting of 'to observe or not to o...

  12. DNA probes

    International Nuclear Information System (INIS)

    The creation of DNA probes for detection of specific nucleotide segments differs from ligand detection in that it is a chemical rather than an immunological reaction. Complementary DNA or RNA is used in place of the antibody and is labelled with 32P. So far, DNA probes have been successfully employed in the diagnosis of inherited disorders, infectious diseases, and for identification of human oncogenes. The latest approach to the diagnosis of communicable and parasitic infections is based on the use of deoxyribonucleic acid (DNA) probes. The genetic information of all cells is encoded by DNA and DNA probe approach to identification of pathogens is unique because the focus of the method is the nucleic acid content of the organism rather than the products that the nucleic acid encodes. Since every properly classified species has some unique nucleotide sequences that distinguish it from every other species, each organism's genetic composition is in essence a finger print that can be used for its identification. In addition to this specificity, DNA probes offer other advantages in that pathogens may be identified directly in clinical specimens

  13. Protein Attachment on Nanodiamonds.

    Science.gov (United States)

    Lin, Chung-Lun; Lin, Cheng-Huang; Chang, Huan-Cheng; Su, Meng-Chih

    2015-07-16

    A recent advance in nanotechnology is the scale-up production of small and nonaggregated diamond nanoparticles suitable for biological applications. Using detonation nanodiamonds (NDs) with an average diameter of ∼4 nm as the adsorbents, we have studied the static attachment of three proteins (myoglobin, bovine serum albumin, and insulin) onto the nanoparticles by optical spectroscopy, mass spectrometry, and dynamic light scattering, and electrophoretic zeta potential measurements. Results show that the protein surface coverage is predominantly determined by the competition between protein-protein and protein-ND interactions, giving each protein a unique and characteristic structural configuration in its own complex. Specifically, both myoglobin and bovine serum albumin show a Langmuir-type adsorption behavior, forming 1:1 complexes at saturation, whereas insulin folds into a tightly bound multimer before adsorption. The markedly different adsorption patterns appear to be independent of the protein concentration and are closely related to the affinity of the individual proteins for the NDs. The present study provides a fundamental understanding for the use of NDs as a platform for nanomedical drug delivery. PMID:25815400

  14. The effect of vibration on bed voidage behaviors in fluidized beds with large particles

    Directory of Open Access Journals (Sweden)

    H. Jin

    2007-09-01

    Full Text Available The effects of vibration parameters, operating conditions and material properties on bed voidage were investigated using an optical fiber probe approach in a vibrating fluidized bed with a diameter of 148 mm. Variables studied included frequency (0-282 s-1, amplitude (0 mm-1 mm, bed height (0.1 m-0.4 m as well as four kinds of particles (belonging to Geldart's B and D groups. The axial and radial voidage distribution with vibration is compared with that without vibration, which shows vibration can aid in the fluidization behaviors of particles. For a larger vibration amplitude, the vibration seriously affects bed voidage. The vibration energy can damp out for particle layers with increasing the bed height. According to analysis of experimental data, an empirical correlation for predicting bed voidage, giving good agreement with the experimental data and a deviation within ±15%, was proposed.

  15. The effect of vibration on bed voidage behaviors in fluidized beds with large particles

    Energy Technology Data Exchange (ETDEWEB)

    Jin, H.; Zhang, J.; Zhang, B.

    2007-07-01

    The effects of vibration parameters, operating conditions and material properties on bed voidage were investigated using an optical fiber probe approach in a vibrating fluidized bed with a diameter of 148 mm. Variables studied included frequency (0-282 s{sup -1}), amplitude (0 mm-1 mm), bed height (0.1 m-0.4 m) as well as four kinds of particles (belonging to Geldart's B and D groups). The axial and radial voidage distribution with vibration is compared with that without vibration, which shows vibration can aid in the fluidization behaviors of particles. For a larger vibration amplitude, the vibration seriously affects bed voidage. The vibration energy can damp out for particle layers with increasing the bed height. According to analysis of experimental data, an empirical correlation for predicting bed voidage, giving good agreement with the experimental data and a deviation within {+-}15%, was proposed. 20 refs., 8 figs., 2 tabs.

  16. 2010 GRC VIBRATIONAL SPECTROSCOPY AUGUST 1 - AUGUST 6, 2010

    Energy Technology Data Exchange (ETDEWEB)

    Brooks Pate

    2010-08-06

    The Vibrational Spectroscopy conference focuses on using vibrational spectroscopy to probe structure and dynamics of molecules in gases, liquids, and at interfaces. The conference explores the wide range of state-of-the-art techniques based on vibrational motion. These techniques span the fields of time-domain, high-resolution frequency-domain, spatially-resolved, nonlinear and multidimensional spectroscopies. The conference highlights the application of these techniques in chemistry, materials, biology, and medicine. The theory of molecular vibrational motion and its connection to spectroscopic signatures and chemical reaction dynamics is the third major theme of the meeting. The goal is to bring together a collection of researchers who share common interests and who will gain from discussing work at the forefront of several connected areas. The intent is to emphasize the insights and understanding that studies of vibrations provide about a variety of molecular systems ranging from small polyatomic molecules to large biomolecules and nanomaterials.

  17. Vibration and Acoustic Radiation from Submerged Spherical Double-Shell

    Institute of Scientific and Technical Information of China (English)

    陈军明; 黄玉盈; 陈应波

    2003-01-01

    Based on the motion differential equations of vibration and acoustic coupling system for a thin elastic spherical double-shell with several elastic plates attached to the shells, in which Dirac-δ functions are employed to introduce the forces and moments applied by the attachments, and by means of expanding field quantities as the Legendre series, a semi-analytic solution is derived for the solution to the vibration and acoustic radiation from a submerged spherical double-shell. This solution has a satisfying computational effectiveness and precision for arbitrary frequency range excitation. It is concluded that the internal plates attached to shells can change significantly the mechanical and acoustical characteristics of shells, and make the coupling system have a very rich resonance frequency spectrum. Moreover, the present method can be used to study the acoustic radiation mechanism of the type of structure.

  18. Ultrafast vibrational energy relaxation of the water bridge.

    Science.gov (United States)

    Piatkowski, Lukasz; Wexler, Adam D; Fuchs, Elmar C; Schoenmaker, Hinco; Bakker, Huib J

    2012-05-14

    We report the energy relaxation of the OH stretch vibration of HDO molecules contained in an HDO:D(2)O water bridge using femtosecond mid-infrared pump-probe spectroscopy. We found that the vibrational lifetime is shorter (~630 ± 50 fs) than for HDO molecules in bulk HDO:D(2)O (~740 ± 40 fs). In contrast, the thermalization dynamics following the vibrational relaxation are much slower (~1.5 ± 0.4 ps) than in bulk HDO:D(2)O (~250 ± 90 fs). These differences in energy relaxation dynamics strongly indicate that the water bridge and bulk water differ on a molecular scale.

  19. Nonlinear targeted energy transfer of two coupled cantilever beams coupled to a bistable light attachment

    Science.gov (United States)

    Mattei, P.-O.; Ponçot, R.; Pachebat, M.; Côte, R.

    2016-07-01

    In order to control the sound radiation by a structure, one aims to control vibration of radiating modes of vibration using "Energy Pumping" also named "Targeted Energy Transfer". This principle is here applied to a simplified model of a double leaf panel. This model is made of two beams coupled by a spring. One of the beams is connected to a nonlinear absorber. This nonlinear absorber is made of a 3D-printed support on which is clamped a buckled thin small beam with a small mass fixed at its centre having two equilibrium positions. The experiments showed that, once attached onto a vibrating system to be controlled, under forced excitation of the primary system, the light bistable oscillator allows a reduction of structural vibration up to 10 dB for significant amplitude and frequency range around the first two vibration modes of the system.

  20. Electron attachment to SF6 and lifetimes of SF6- negative ions

    CERN Document Server

    Gerchikov, L G

    2008-01-01

    We study the process of low-energy electron capture by the SF6 molecule. Our approach is based on the model of Gauyacq and Herzenberg [J. Phys. B 17, 1155 (1984)] in which the electron motion is coupled to the fully symmetric vibrational mode through a weakly bound or virtual s state. By tuning the two free parameters of the model, we achieve an accurate description of the measured electron attachment cross section and good agreement with vibrational excitation cross sections of the fully symmetric mode. An extension of the model provides a limit on the characteristic time of intramolecular vibrational relaxation in highly-excited SF6-. By evaluating the total vibrational spectrum density of SF6-, we estimate the widths of the vibrational Feshbach resonances of the long-lived negative ion. We also analyse the possible distribution of the widths and its effect on the lifetime measurements, and investigate nonexponential decay features in metastable SF6-.

  1. Reorientation of the ‘free OH’ group in the top-most layer of air/water interface of sodium fluoride aqueous solution probed with sum-frequency generation vibrational spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Feng, Ran-Ran; Guo, Yuan; Wang, Hongfei

    2014-09-17

    Many experimental and theoretical studies have established the specific anion, as well as cation effects on the hydrogen-bond structures at the air/water interface of electrolyte solutions. However, the ion effects on the top-most layer of the air/water interface, which is signified by the non-hydrogen-bonded so-called ‘free O-H’ group, has not been discussed or studied. In this report, we present the measurement of changes of the orientational angle of the ‘free O-H’ group at the air/water interface of the sodium fluoride (NaF) solutions at different concentrations using the interface selective sum-frequency generation vibrational spectroscopy (SFG-VS) in the ssp and ppp polarizations. The polarization dependent SFG-VS results show that the average tilt angle of the ‘free O-H’ changes from about 35.3 degrees ± 0.5 degrees to 43.4 degrees ± 2.1degrees as the NaF concentration increase from 0 to 0.94M (nearly saturated). Such tilt angle change is around the axis of the other O-H group of the same water molecule at the top-most layer at the air/water interface that is hydrogen-bonded to the water molecules below the top-most layer. These results provide quantitative molecular details of the ion effects of the NaF salt on the structure of the water molecules at the top-most layer of the air/water interfacial, even though both the Na+ cation and the F- anion are believed to be among the most excluded ions from the air/water interface.

  2. Diameters in preferential attachment models

    NARCIS (Netherlands)

    Dommers, S.; Van der Hofstad, R.; Hooghiemstra, G.

    2010-01-01

    In this paper, we investigate the diameter in preferential attachment (PA-) models, thus quantifying the statement that these models are small worlds. The models studied here are such that edges are attached to older vertices proportional to the degree plus a constant, i.e., we consider affine PA-mo

  3. Association between attachment and schizotypy

    OpenAIRE

    Dunne, Colm

    2011-01-01

    Background: The human genome project has affirmed the importance of non-genetic factors in human development. Attachment style is considered to be a diathesis for psychopathology and an important determinant regarding interpersonal functioning. Epidemiological research has indicated that there is significant aetiological continuity between symptoms of schizotypy and clinical symptoms of schizophrenia. Limited research has investigated the association between attachment and schi...

  4. Attachment, caring and prosocial behavior

    NARCIS (Netherlands)

    Erez, Ayelet

    2007-01-01

    The thesis focuses on 5 studies examining the role of adult attachment in volunteering by defining volunteerism as a form of caregiving. By that we suggest an effect of one behavioral system, attachment, on another, caring or prosocial behaviors in individual or group settings. Studies 1 and 2 ex

  5. Vibrating fuel grapple. [LMFBR

    Science.gov (United States)

    Chertock, A.J.; Fox, J.N.; Weissinger, R.B.

    A reactor refueling method is described which utilizes a vibrating fuel grapple for removing spent fuel assemblies from a reactor core. It incorporates a pneumatic vibrator in the grapple head which allows additional withdrawal capability without exceeding the allowable axial force limit. The only moving part in the vibrator is a steel ball, pneumatically driven by a gas, such as argon, around a track, with centrifugal force created by the ball being transmitted through the grapple to the assembly handling socket.

  6. Vibrational properties of uracil

    Institute of Scientific and Technical Information of China (English)

    WANG Zhiping; ZHANG Fengshou; ZENG Xianghua; ZHOU Hongyu; GU Bin; CHENG Wei

    2006-01-01

    A semiempirical molecular dynamics model is developed to study the vibrational frequencies of uracil at very low kinetic temperature by using the Fourier transform of velocity autocorrelation function of trajectories of molecular dynamics simulations. The finite difference harmonic method is used to assign the vibrational frequency of each mode. The calculated frequencies are found to be in good agreement with experimental measurements. Moreover, we make up for the lost vibrational modes in experiments self-consistently. A total of 30 vibrational modes and their corresponding frequencies are reported.

  7. PREFACE: Vibrations at surfaces Vibrations at surfaces

    Science.gov (United States)

    Rahman, Talat S.

    2011-12-01

    This special issue is dedicated to the phenomenon of vibrations at surfaces—a topic that was indispensible a couple of decades ago, since it was one of the few phenomena capable of revealing the nature of binding at solid surfaces. For clean surfaces, the frequencies of modes with characteristic displacement patterns revealed how surface geometry, as well as the nature of binding between atoms in the surface layers, could be different from that in the bulk solid. Dispersion of the surface phonons provided further measures of interatomic interactions. For chemisorbed molecules on surfaces, frequencies and dispersion of the vibrational modes were also critical for determining adsorption sites. In other words, vibrations at surfaces served as a reliable means of extracting information about surface structure, chemisorption and overlayer formation. Experimental techniques, such as electron energy loss spectroscopy and helium-atom-surface scattering, coupled with infra-red spectroscopy, were continually refined and their resolutions enhanced to capture subtleties in the dynamics of atoms and molecules at surfaces. Theoretical methods, whether based on empirical and semi-empirical interatomic potential or on ab initio electronic structure calculations, helped decipher experimental observations and provide deeper insights into the nature of the bond between atoms and molecules in regions of reduced symmetry, as encountered on solid surfaces. Vibrations at surfaces were thus an integral part of the set of phenomena that characterized surface science. Dedicated workshops and conferences were held to explore the variety of interesting and puzzling features revealed in experimental and theoretical investigations of surface vibrational modes and their dispersion. One such conference, Vibrations at Surfaces, first organized by Harald Ibach in Juelich in 1980, continues to this day. The 13th International Conference on Vibrations at Surfaces was held at the University of

  8. Infrared vibrational nanocrystallography and nanoimaging

    Science.gov (United States)

    Muller, Eric A.; Pollard, Benjamin; Bechtel, Hans A.; van Blerkom, Peter; Raschke, Markus B.

    2016-01-01

    Molecular solids and polymers can form low-symmetry crystal structures that exhibit anisotropic electron and ion mobility in engineered devices or biological systems. The distribution of molecular orientation and disorder then controls the macroscopic material response, yet it is difficult to image with conventional techniques on the nanoscale. We demonstrated a new form of optical nanocrystallography that combines scattering-type scanning near-field optical microscopy with both optical antenna and tip-selective infrared vibrational spectroscopy. From the symmetry-selective probing of molecular bond orientation with nanometer spatial resolution, we determined crystalline phases and orientation in aggregates and films of the organic electronic material perylenetetracarboxylic dianhydride. Mapping disorder within and between individual nanoscale domains, the correlative hybrid imaging of nanoscale heterogeneity provides insight into defect formation and propagation during growth in functional molecular solids. PMID:27730212

  9. Investigating two-photon double ionization of D2 by XUV-Pump -- XUV-Probe experiments at FLASH

    Energy Technology Data Exchange (ETDEWEB)

    FLASH Collaboration; Jiang, Y.; Rudenko, A.; Perez-Torres, J.; Foucar, L.; Kurka, M.; Kuhnel, K.; Toppin, M.; Plesiat, E.; Morales, F.; Martin, F.; Herrwerth, O.; Lezius, M.; Kling, M.; Jahnke, T.; Dorner, R.; Sanz-Vicario, J.; van Tilborg, J.; Belkacem, A.; Schulz, M.; Ueda, K.; Zouros, T.; Dusterer, S.; Treusch, R.; Schroter, C.; Moshammer, R.; Ullrich, J.

    2010-08-02

    Using a novel split-mirror set-up attached to a Reaction Microscope at the Free electron LASer in Hamburg (FLASH) we demonstrate an XUV-pump -- XUV-probe ((hbar omega = 38 eV) experiment by tracing the ultra-fast nuclear wave-packet motion in the D2+ (1s sigma g-state) with<10 fs time resolution. Comparison with time-dependent calculations yields excellent agreement with the measured vibrational period of 22+-4 fs in D2+, points to the importance of the inter-nuclear distance dependent ionization probability and paves the way to control sequential and non-sequential two-photon double ionization contributions.

  10. TIME-RESOLVED VIBRATIONAL SPECTROSCOPY

    Energy Technology Data Exchange (ETDEWEB)

    Andrei Tokmakoff, MIT (Conference Chair); Paul Champion, Northeastern University; Edwin J. Heilweil, NIST; Keith A. Nelson, MIT; Larry Ziegler, Boston University

    2009-05-14

    This document contains the Proceedings from the 14th International Conference on Time-Resolved Vibrational Spectroscopy, which was held in Meredith, NH from May 9-14, 2009. The study of molecular dynamics in chemical reaction and biological processes using time-resolved spectroscopy plays an important role in our understanding of energy conversion, storage, and utilization problems. Fundamental studies of chemical reactivity, molecular rearrangements, and charge transport are broadly supported by the DOE’s Office of Science because of their role in the development of alternative energy sources, the understanding of biological energy conversion processes, the efficient utilization of existing energy resources, and the mitigation of reactive intermediates in radiation chemistry. In addition, time-resolved spectroscopy is central to all five of DOE’s grand challenges for fundamental energy science. The Time-Resolved Vibrational Spectroscopy conference is organized biennially to bring the leaders in this field from around the globe together with young scientists to discuss the most recent scientific and technological advances. The latest technology in ultrafast infrared, Raman, and terahertz spectroscopy and the scientific advances that these methods enable were covered. Particular emphasis was placed on new experimental methods used to probe molecular dynamics in liquids, solids, interfaces, nanostructured materials, and biomolecules.

  11. University scientists test Mars probe equipment

    CERN Multimedia

    2002-01-01

    Scientists at Leicester University have spent four years researching and designing the Flight Model Position Adjustable Workbench (PAW) at the university. It will be attached to the Beagle 2 probe before being sent to the Red Planet in the spring (1/2 page).

  12. Floor Vibrations - as Induced and Reduced by Humans

    DEFF Research Database (Denmark)

    Pedersen, Lars

    The work is a contribution to the problem of modelling human-induced dynamic loads on floors and to the problem of modelling the interaction between stationary crowds of people and a vibrating floor. Experimental investigations are made to examine, update and refine currently available models....... As for dynamic loads focus is placed on heel impact excitation and actions of jumping people causing floor vibrations. As for interaction between stationary humans and the vibrating floor focus is on modelling humans as oscillating spring-mass-damper systems attached to the floor rather than as simple added mass....... The appropriateness and accuracy of this modelling approach is evaluated. Implications of human-floor interaction are studied with focus on the impact of the interaction on the size of vibration levels of human-occupied floors and on the impact on floor dynamic characteristics. The influence of the interaction...

  13. The vibrational spectrum of the atoms in the grain boundaries of nanocrystalline Pd

    Energy Technology Data Exchange (ETDEWEB)

    Stuhr, U. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Wipf, H.; Hahn, H. [Technische Hochschule Darmstadt (Germany); Natter, H.; Hemperlmann, R. [Universitaet des Saarlandes, Saarbruecken (Germany); Andersen, K. [Institut Max von Laue - Paul Langevin (ILL), 38 - Grenoble (France)

    1997-09-01

    The vibrational excitations of the atoms in nanocrystalline Pd was investigated by neutron-time-of-flight spectroscopy. Hydrogen was used as a probe for the vibrations in the grain boundaries. The separation between the H and Pd vibrations was done by spin analysis. The results show that in the grain boundary the density of states of low energy excitations ({<=}5 meV) is drastically increased. (author) 3 figs., 3 refs.

  14. Vibration Suppression of Electronic Box by a Dual Function Piezoelectric Energy Harvester-Tuned Vibration Absorber

    Directory of Open Access Journals (Sweden)

    Sajid Rafique

    2014-04-01

    Full Text Available Over the past few years, remarkable developments in piezoelectric materials have motivated many researchers to work in the field of vibration energy harvesting by using piezoelectric beam like smart structures. This paper aimed to present the most recent application of a dual function piezoelectric device which can suppress vibration and harvest vibration energy simultaneously and a brief illustration of conventional mechanical and electrical TVAs (Tuned Vibration Absorber. It is shown that the proposed dual function device combines the benefits of conventional mechanical and electrical TVAs and reduces their relative disadvantages. Conversion of mechanical energy into electrical energy introduces damping and, hence, the optimal damping required by this TVA is generated by the energy harvesting effects. This paper presents the methodology of implementing the theory of 'electromechanical' TVAs to suppress the response of any real world structure. The work also illustrates the prospect of extensive applications of such novel "electromechanical" TVAs in defence and industry. The results show that the optimum degree of vibration suppression of an electronic box is achieved by this dual function TVA through suitable tuning of the attached electrical circuitry

  15. Vibration Suppression of an Axially Moving String with Transverse Wind Loadings by a Nonlinear Energy Sink

    Directory of Open Access Journals (Sweden)

    Ye-Wei Zhang

    2013-01-01

    Full Text Available Nonlinear targeted energy transfer (TET is applied to suppress the excessive vibration of an axially moving string with transverse wind loads. The coupling dynamic equations used are modeled by a nonlinear energy sink (NES attached to the string to absorb vibrational energy. By a two-term Galerkin procedure, the equations are discretized, and the effects of vibration suppression by numerical methods are demonstrated. Results show that the NES can effectively suppress the vibration of the axially moving string with transverse wind loadings, thereby protecting the string from excessive movement.

  16. Mechanical vibration and shock analysis, sinusoidal vibration

    CERN Document Server

    Lalanne, Christian

    2014-01-01

    Everything engineers need to know about mechanical vibration and shock...in one authoritative reference work! This fully updated and revised 3rd edition addresses the entire field of mechanical vibration and shock as one of the most important types of load and stress applied to structures, machines and components in the real world. Examples include everything from the regular and predictable loads applied to turbines, motors or helicopters by the spinning of their constituent parts to the ability of buildings to withstand damage from wind loads or explosions, and the need for cars to m

  17. Picking up good vibrations

    NARCIS (Netherlands)

    Eijk, A.

    2010-01-01

    The methods that need to be employed to develop the better vibration guidelines to assess the integrity of a reciprocating compressor system are discussed. An R&D project of the European Forum of Reciprocating Compressors (EFRC) has been initiated to develop guidelines for vibrations in reciprocatin

  18. Hydroelastic Vibrations of Ships

    DEFF Research Database (Denmark)

    Jensen, Jørgen Juncher; Folsø, Rasmus

    2002-01-01

    A formula for the necessary hull girder bending stiffness required to avoid serious springing vibrations is derived. The expression takes into account the zero crossing period of the waves, the ship speed and main dimensions. For whipping vibrations the probability of exceedance for the combined ...

  19. Vibration Theory, Vol. 3

    DEFF Research Database (Denmark)

    Nielsen, Søren R. K.

    The present textbook has been written based on previous lecture notes for a course on stochastic vibration theory that is being given on the 9th semester at Aalborg University for M. Sc. students in structural engineering. The present 4th edition of this textbook on linear stochastic vibration...

  20. Vibration Theory, Vol. 3

    DEFF Research Database (Denmark)

    Nielsen, Søren R. K.

    The present textbook has been written based on previous lecture notes for a course on stochastic vibration theory that is being given on the 9th semester at Aalborg University for M. Sc. students in structural engineering. The present 2nd edition of this textbook on linear stochastic vibration...

  1. Everything You Want To Know about Attachment.

    Science.gov (United States)

    Honig, Alice Sterling

    This paper discusses infant attachment, which it defines as a long-lasting emotional bond revealed when a child under stress seeks out and tries to stay close to a specific figure. The paper addresses: (1) What is attachment? Who are the pioneers in attachment theory?; (2) How do we notice attachment in action?; (3) Is attachment the only…

  2. Attachment at work and performance.

    Science.gov (United States)

    Neustadt, Elizabeth A; Chamorro-Premuzic, Tomas; Furnham, Adrian

    2011-09-01

    This paper examines the relations between self-reported attachment orientation at work and personality, self-esteem, trait emotional intelligence (aka emotional self-efficacy), and independently assessed career potential and job performance. Self-report data were collected from 211 managers in an international business in the hospitality industry; independent assessments of these managers' job performance and career potential were separately obtained from the organization. A self-report measure of romantic attachment was adapted for application in the work context; a two-factor solution was found for this measure. Secure/autonomous attachment orientation at work was positively related to self-esteem, trait emotional intelligence, extraversion, agreeableness, and conscientiousness, and also to job performance. Not only was secure/autonomous attachment orientation at work statistically predictive of job performance, but the new measure also made a distinct contribution, beyond conscientiousness, to this prediction. PMID:21838647

  3. Social attachments and traumatic stress

    Directory of Open Access Journals (Sweden)

    Richard A. Bryant

    2016-03-01

    Full Text Available The extent to which we engage with our social world has been central to our survival as a species and, accordingly, is relevant to how we cope with trauma and adversity. This review summarises current knowledge about the importance of social connections from an evolutionary perspective, as well as integrating this with a discussion of prevailing attachment theories. Experimental research supporting the potential benefit of attachments for managing adversity are presented, along with a review of how these benefits are moderated by individual differences in attachment style. The potential impact of trauma on attachment systems, and the manner in which this can compound trauma stress is discussed. Finally, a broader overview of social network analysis is introduced and it is proposed that a more sociocentric framework of trauma response would promote a fuller understanding of how social processes moderate trauma response.

  4. Electron attachment to fluorocarbon radicals

    Science.gov (United States)

    Shuman, Nicholas

    2014-10-01

    Most plasma environments contain populations of short-lived species such as radicals, the chemistry of which can have significant effects on the overall chemistry of the system. However, few experimental measurements of the kinetics of electron attachment to radicals exist due to the inherent difficulties of working with transient species. Calculations from first principles have been attempted, but are arduous and, because electron attachment is so sensitive to the specifics of the potential surface, their accuracy has not been established. Electron attachment to small fluorocarbon radicals is particularly important, as the data are needed for predictive modeling of plasma etching of semiconductor materials, a key process in the industrial fabrication of microelectronics. We have recently developed a novel flowing afterglow technique to measure several types of otherwise difficult to study plasma processes, including thermal electron attachment to radicals. Variable Electron and Neutral Density Attachment Mass Spectrometry (VENDAMS) exploits dissociative electron attachment in a weakly ionized plasma as a radical source. Here, we apply VENDAMS to a series of halofluorocarbon precursors in order to measure the kinetics of thermal electron attachment to fluorocarbon radicals. Results are presented for CF2, CF3, C2F5,C2F3,1-C3F7, 2-C3F7, and C3F5 from 300 K to 900 K. Both the magnitude and the temperature dependences of rate coefficients as well as product branching between associative and dissociative attachment are highly system specific; however, thermal attachment to all species is inefficient, never exceeding 5% of the collision rate. The data are analyzed using a recently developed kinetic modeling approach, which uses extended Vogt-Wannier theory as a starting point, accounts for dynamic effects such as coupling between the electron and nuclear motions through empirically validated functional forms, and finally uses statistical theory to determine the fate of

  5. Attachment Narratives in Refugee Children

    DEFF Research Database (Denmark)

    De Haene, L.; Dalgård, Nina Thorup; Montgomery, E.;

    2013-01-01

    J Trauma Stress. 2013 Jun;26(3):413-7. doi: 10.1002/jts.21820. Attachment narratives in refugee children: interrater reliability and qualitative analysis in pilot findings from a two-site study.......J Trauma Stress. 2013 Jun;26(3):413-7. doi: 10.1002/jts.21820. Attachment narratives in refugee children: interrater reliability and qualitative analysis in pilot findings from a two-site study....

  6. Vibrational Spectroscopy and Dynamics of Water.

    Science.gov (United States)

    Perakis, Fivos; Marco, Luigi De; Shalit, Andrey; Tang, Fujie; Kann, Zachary R; Kühne, Thomas D; Torre, Renato; Bonn, Mischa; Nagata, Yuki

    2016-07-13

    We present an overview of recent static and time-resolved vibrational spectroscopic studies of liquid water from ambient conditions to the supercooled state, as well as of crystalline and amorphous ice forms. The structure and dynamics of the complex hydrogen-bond network formed by water molecules in the bulk and interphases are discussed, as well as the dissipation mechanism of vibrational energy throughout this network. A broad range of water investigations are addressed, from conventional infrared and Raman spectroscopy to femtosecond pump-probe, photon-echo, optical Kerr effect, sum-frequency generation, and two-dimensional infrared spectroscopic studies. Additionally, we discuss novel approaches, such as two-dimensional sum-frequency generation, three-dimensional infrared, and two-dimensional Raman terahertz spectroscopy. By comparison of the complementary aspects probed by various linear and nonlinear spectroscopic techniques, a coherent picture of water dynamics and energetics emerges. Furthermore, we outline future perspectives of vibrational spectroscopy for water researches. PMID:27096701

  7. Fingertip contact suppresses the destabilizing influence of leg muscle vibration

    Science.gov (United States)

    Lackner, J. R.; Rabin, E.; DiZio, P.

    2000-01-01

    Touch of the hand with a stationary surface at nonmechanically supportive force levels (physiotherapy vibrator (120 Hz) was applied approximately 5 cm above the malleolous to stimulate the peroneus longus and brevis tendons. Touch conditions involved contact of the right index finger with a laterally positioned surface ( 0.05) from each other and both had significantly less mean sway amplitude of head and of center of pressure than the other conditions (P < 0.01). In experiment 2, eight subjects stood heel-to-toe under touch and no-touch conditions involving 40-s duration trials of peroneus tendon vibration at different duty cycles: 1-, 2-, 3-, and 4-s ON and OFF periods. The vibrator was attached to the subject's leg and remotely activated. In the no-touch conditions, subjects showed periodic postural disruptions contingent on the duty cycle and mirror image rebounds with the offset of vibration. In the touch conditions, subjects were much less disrupted and showed compensations occurring within 500 ms of vibration onset and mirror image rebounds with vibration offset. Subjects were able to suppress almost completely the destabilizing influence of the vibration in the 3- and 4-s duty cycle trials. These experiments show that haptic contact of the hand with a stable surface can suppress abnormal proprioceptive and motor signals in leg muscles.

  8. Electrorheological vibration system

    Science.gov (United States)

    Korobko, Evguenia V.; Shulman, Zinovy P.; Korobko, Yulia O.

    2001-07-01

    The present paper is devoted to de3velopment and testing of an active vibration system. The system is intended for providing efficient motion of a piston in a hydraulic channel for creation of shocks and periodic vibrations in a low frequency range by means of the ER-valves based on an electrosensitive working me dium, i.e. electrorheological fluids. The latter manifests the electrorheological (ER) effect, i.e. a reversible change in the rheological characteristics of weak-conducting disperse compositions in the presence of constant and alternating electric fields. As a result of the experimental study of the dependence of viscoelastic properties of the ER-fluid on the magnitude and type of an electric field, the optimum dimensions of the vibrator and the its valves characteristics of the optimal electrical signal are determined. For control of an ER- vibrator having several valves we have designed a special type of a high-voltage two-channel impulse generator. Experiments were conducted at the frequencies ranged from 1- 10 Hz. It has been shown, that a peak force made 70% of the static force exercised by the vibrator rod. A phase shift between the input voltage and the load acceleration was less than 45 degree(s)C which allowed servocontrol and use of the vibrator for attendant operations. It was noted that a response of the vibrator to a stepwise signal has a delay only of several milliseconds.

  9. Fluid Surface Damping: A Technique for Vibration Suppression of Beams

    Directory of Open Access Journals (Sweden)

    Hany Ghoneim

    1997-01-01

    Full Text Available A fluid surface damping (FSD technique for vibration suppression of beamlikestructures is proposed. The technique is a modification of the surface layer damping method. Two viscoelastic surface layers containing fluid-filled cavities are attached symmetrically to the opposite surfaces of the beam. The cavities on one side are attached to the corresponding cavities on the other side via connection passages. As the beam vibrates, the fluid is pumped back and forth through the connecting passages. Therefore, in addition to the viscoelastic damping provided by the surface layers, the technique offers viscous damping due to the fluid flow through the passage. A mathematical model for the proposed technique is developed, normalized, and solved in the frequency domain to investigate the effect of various parameters on the vibration suppression of a cantilever beam. The steady-state frequency response for a base white-noise excitation is calculated at the beam's free tip and over a frequency range containing the first five resonant frequencies. The parameters investigated are the flow-through passage viscous resistance, the length and location of the layers, the hydraulic capacitance of the fluid-filled cavities, and inertia of the moving fluid (hydraulic inertance. Results indicate that the proposed technique has promising potential in the field of vibration suppression of beamlike structures. With two FSD elements, all peak vibration amplitudes can be well suppressed over the entire frequency spectrum studied.

  10. Effect of Muscle Vibration on Postural Balance of Parkinson’s Diseases Patients in Bipedal Quiet Standing

    OpenAIRE

    Han, Jintae; Jung, Jaemin; Lee, Junghoon; Kim, Eunjung; Lee, Myunghee; Lee, Keunhee

    2013-01-01

    [Purpose] The purpose of this study was to investigate the effect of muscle vibration applied to the lower extremities on static postural balance of patients with Parkinson’s disease (PD). [Subjects] Seven subjects with Parkinson’s disease participated in this study. [Methods] The oscillators of vibration were attached to the muscle bellies of the tibialis anterior, gastrocnemius, biceps femoris, and rectus femoris on both sides of the lower extremities with adhesive tape. A vibration frequen...

  11. Coherent vibrational dynamics

    CERN Document Server

    Lanzani, Guglielmo; De Silvestri, Sandro

    2007-01-01

    Vibrational spectroscopy is a powerful investigation tool for a wide class of materials covering diverse areas in physics, chemistry and biology. The continuous development in the laser field regarding ultrashort pulse generation has led to the possibility of producing light pulses that can follow vibrational motion coupled to the electronic transitions in molecules and solids in real time. Aimed at researchers and graduate students using vibrational spectroscopy, this book provides both introductory chapters as well as more advanced contents reporting on recent progress. It also provides a good starting point for scientists seeking a sound introduction to ultrafast optics and spectroscopic techniques.

  12. Quenching methods for background reduction in luminescence-based probe-target binding assays

    Science.gov (United States)

    Cai, Hong; Goodwin, Peter M; Keller, Richard A.; Nolan, Rhiannon L.

    2007-04-10

    Background luminescence is reduced from a solution containing unbound luminescent probes, each having a first molecule that attaches to a target molecule and having an attached luminescent moiety, and luminescent probe/target adducts. Quenching capture reagent molecules are formed that are capable of forming an adduct with the unbound luminescent probes and having an attached quencher material effective to quench luminescence of the luminescent moiety. The quencher material of the capture reagent molecules is added to a solution of the luminescent probe/target adducts and binds in a proximity to the luminescent moiety of the unbound luminescent probes to quench luminescence from the luminescent moiety when the luminescent moiety is exposed to exciting illumination. The quencher capture reagent does not bind to probe molecules that are bound to target molecules and the probe/target adduct emission is not quenched.

  13. Vibration Analysis of a Residential Building

    Directory of Open Access Journals (Sweden)

    Sampaio Regina Augusta

    2015-01-01

    Full Text Available The aim of this paper is to present the results of a study regarding vibration problems in a 17 storey residential building during pile driving in its vicinity. The structural design of the building was checked according to the Brazilian standards NBR6118 and NBR6123, and using commercial finite element software. An experimental analysis was also carried out using low frequency piezo-accelerometers attached to the building structure. Structure vibrations were recorded under ambient conditions. Four monitoring tests were performed on different days. The objective of the first monitoring test was an experimental modal analysis. To obtain de modal parameters, data was processed in the commercial software ARTEMIS employing two methods: the Stochastic Subspace Identification and the Frequency Domain Decomposition. Human comfort was investigated considering the International Standard ISO 2631. The Portuguese standard, NP2074, was also used as a reference, since it aims to limit the adverse effects of vibrations in structures caused by pile driving in the vicinity of the structure. The carried out experimental tests have shown that, according to ISO2301, the measure vibration levels are above the acceptance limits. However, velocity peaks are below the limits established by NP2074. It was concluded that, although the structure has adequate capacity to resist internal forces according to normative criteria, it has low horizontal stiffness, which could be verified by observing the vibration frequencies and mode shapes obtained with the finite element models, and its similarity with the experimental results. Thus, the analyses indicate the occurrence of discomfort by the residents.

  14. Determining the static electronic and vibrational energy correlations via two-dimensional electronic-vibrational spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Hui; Lewis, Nicholas H. C.; Oliver, Thomas A. A.; Fleming, Graham R., E-mail: grfleming@lbl.gov [Department of Chemistry, University of California, Berkeley, California 94720 (United States); Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, Californial 94720 (United States); Kavli Energy NanoSciences Institute at Berkeley, Berkeley, California 94720 (United States)

    2015-05-07

    Changes in the electronic structure of pigments in protein environments and of polar molecules in solution inevitably induce a re-adaption of molecular nuclear structure. Both changes of electronic and vibrational energies can be probed with visible or infrared lasers, such as two-dimensional electronic spectroscopy or vibrational spectroscopy. The extent to which the two changes are correlated remains elusive. The recent demonstration of two-dimensional electronic-vibrational (2DEV) spectroscopy potentially enables a direct measurement of this correlation experimentally. However, it has hitherto been unclear how to characterize the correlation from the spectra. In this paper, we present a theoretical formalism to demonstrate the slope of the nodal line between the excited state absorption and ground state bleach peaks in the spectra as a characterization of the correlation between electronic and vibrational transition energies. We also show the dynamics of the nodal line slope is correlated to the vibrational spectral dynamics. Additionally, we demonstrate the fundamental 2DEV spectral line-shape of a monomer with newly developed response functions.

  15. Damping Vibration at an Impeller

    Science.gov (United States)

    Hager, J. A.; Rowan, B. F.

    1982-01-01

    Vibration of pump shaft is damped at impeller--where vibration-induced deflections are greatest--by shroud and seal. Damping reduces vibrational motion of shaft at bearings and load shaft places on them. Flow through clearance channel absorbs vibration energy.

  16. Activating Attachments Reduces Memories of Traumatic Images.

    Science.gov (United States)

    Bryant, Richard A; Foord, Rachael

    2016-01-01

    Emotional memories, and especially intrusive memories, are a common feature of many psychological disorders, and are overconsolidated by stress. Attachment theory posits that activation of mental representations of attachment figures can reduce stress and boost coping. This study tested the proposition that attachment activation would reduce consolidation of emotional and intrusive memories. Sixty-seven undergraduate students viewed subliminal presentations of traumatic and neutral images, which were preceded by subliminal presentations of either attachment-related images or non-attachment-related images; free recall and intrusive memories were assessed two days later. Participants with low avoidant attachment tendencies who received the attachment primes recalled fewer memories and reported fewer intrusions than those who received the non-attachment primes. Unexpectedly, those with high anxious attachment tendencies reported fewer memories. These findings generally accord with attachment theory, and suggest that consolidation of emotional memories can be moderated by activation of attachment representations. PMID:27631498

  17. NIF Ambient Vibration Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Noble, C.R.; Hoehler, M.S., S.C. Sommer

    1999-11-29

    LLNL has an ongoing research and development project that includes developing data acquisition systems with remote wireless communication for monitoring the vibrations of large civil engineering structures. In order to establish the capability of performing remote sensing over an extended period of time, the researchers needed to apply this technology to a real structure. The construction of the National Ignition Facility provided an opportunity to test the data acquisition system on a large structure to monitor whether the facility is remaining within the strict ambient vibration guidelines. This document will briefly discuss the NIF ambient vibration requirements and summarize the vibration measurements performed during the Spring and Summer of 1999. In addition, a brief description of the sensors and the data acquisition systems will be provided in Appendix B.

  18. NIF Ambient Vibration Measurements

    International Nuclear Information System (INIS)

    LLNL has an ongoing research and development project that includes developing data acquisition systems with remote wireless communication for monitoring the vibrations of large civil engineering structures. In order to establish the capability of performing remote sensing over an extended period of time, the researchers needed to apply this technology to a real structure. The construction of the National Ignition Facility provided an opportunity to test the data acquisition system on a large structure to monitor whether the facility is remaining within the strict ambient vibration guidelines. This document will briefly discuss the NIF ambient vibration requirements and summarize the vibration measurements performed during the Spring and Summer of 1999. In addition, a brief description of the sensors and the data acquisition systems will be provided in Appendix B

  19. Vibration enhanced quantum transport

    CERN Document Server

    Semião, F L; Milburn, G J

    2009-01-01

    In this paper, we study the role of a collective vibrational motion in the phenomenon of electronic energy transfer (EET) between chromophores with different electronic transition frequencies. Previous experimental work on EET in conjugated polymer samples has suggested that the common structural framework of the macromolecule introduce correlations in the energy gap fluctuations which cause coherent EET. We present a simple model describing the coupling between the chromophores and a common vibrational mode, and find that vibration can indeed lead to an enhancement in the transport of excitations across the quantum network. Furthermore, in our model phase information is partially retained in the transfer process from a donor to an acceptor, as experimentally demonstrated in the conjugated polymer system. Consequently, this mechanism of vibration enhanced quantum transport might find applications in quantum information transfer of qubit states or entanglement.

  20. Vibrational Excitation of Ammonia Molecules by FEL-SUT

    CERN Document Server

    Ogi, Yoshihiro

    2004-01-01

    Free Electron Laser at Tokyo University of Science (FEL-SUT) was employed for exciting single vibrational modes of ammonia molecules. FEL is tuned to 10.5 μm, corresponding to the X1A1' (ν2 = 1) ← (ν2 = 0) transition of NH3. The population of the vibrationally excited states is probed by the (2 + 1) resonance enhanced multiphoton ionization (REMPI) technique via the B 1E" Rydberg state. Maximum excitation efficiency of ν2 = 1 ← ν2 = 0 transition was about 50 %, which was estimated by taking account of Franck-Condon factors and the rotational line strengths. Rotational analyses of the spectra revealed that vibrational ladder climbing up to ν2 = 2 in NH3 was realized for the first time. Experimental results on ν4 vibrational excitation of NH3 and ND3 will be also reported.

  1. Modeling vibration response and damping of cables and cabled structures

    Science.gov (United States)

    Spak, Kaitlin S.; Agnes, Gregory S.; Inman, Daniel J.

    2015-02-01

    In an effort to model the vibration response of cabled structures, the distributed transfer function method is developed to model cables and a simple cabled structure. The model includes shear effects, tension, and hysteretic damping for modeling of helical stranded cables, and includes a method for modeling cable attachment points using both linear and rotational damping and stiffness. The damped cable model shows agreement with experimental data for four types of stranded cables, and the damped cabled beam model shows agreement with experimental data for the cables attached to a beam structure, as well as improvement over the distributed mass method for cabled structure modeling.

  2. Hamiltonian Dynamics of Preferential Attachment

    CERN Document Server

    Zuev, Konstantin; Krioukov, Dmitri

    2015-01-01

    Prediction and control of network dynamics are grand-challenge problems in network science. The lack of understanding of fundamental laws driving the dynamics of networks is among the reasons why many practical problems of great significance remain unsolved for decades. Here we study the dynamics of networks evolving according to preferential attachment, known to approximate well the large-scale growth dynamics of a variety of real networks. We show that this dynamics is Hamiltonian, thus casting the study of complex networks dynamics to the powerful canonical formalism, in which the time evolution of a dynamical system is described by Hamilton's equations. We derive the explicit form of the Hamiltonian that governs network growth in preferential attachment. This Hamiltonian turns out to be nearly identical to graph energy in the configuration model, which shows that the ensemble of random graphs generated by preferential attachment is nearly identical to the ensemble of random graphs with scale-free degree d...

  3. Diameters in preferential attachment models

    OpenAIRE

    Dommers, S.; van der Hofstad, R.; Hooghiemstra, G.

    2010-01-01

    In this paper, we investigate the diameter in preferential attachment (PA-) models, thus quantifying the statement that these models are small worlds. The models studied here are such that edges are attached to older vertices proportional to the degree plus a constant, i.e., we consider affine PA-models. There is a substantial amount of literature proving that, quite generally, PA-graphs possess power-law degree sequences with a power-law exponent \\tau>2. We prove that the diameter of the PA-...

  4. Vibration reduction on automotive shafts using piezoceramics

    Science.gov (United States)

    Kunze, Holger; Riedel, Mathias; Schmidt, Knut; Bianchini, Emanuele

    2003-08-01

    This paper reports an experimental study on active vibration reduction for automotive shafts with the use of piezoelectric material. The work focuses on an axle of an Audi A2. The demand in the automobile sector for higher comfort in the vehicle is of a great importance alongside the requirements of lighter weight and low fuel consumption. These requirements are typically in conflict with each other. One solution is the use of intelligent materials instead of viscoelastic materials and proof mass absorbers. These solutions are quite heavy especially at low frequencies. Active vibration control and piezoelectric devices are advantageous in this application due to their low mass to performance ratio. Our research study explores the use of such piezoelectric devices for an axle. In conjunction with electronics it will reduce vibrations in the first natural bending mode of the axle. Laboratory tests simulated the condition present in the road. At first a stationary set up was used, then a simulated disturbance was input at the attachment points of the shaft. Finally, a test with rotating shaft was performed. Piezoelectric devices (custom QuickPacks from ACX, a Division of Cymer) were used as sensors and as actuators to properly control the axle during the different operating conditions. The power consumption of each actuator pair was less than 20W. The work described here details the test setup, the control strategy, the hardware implementation as well as the test results obtained.

  5. Bubble oscillations and motion under vibration

    CERN Document Server

    O'Hern, Tim; Torczynski, John

    2011-01-01

    Bubbles under vibration can behave in unusual ways, e.g., moving downward against the force of buoyancy. While the bubble downward motion due to the Bjerknes force is well known at acoustic frequencies close to the bubble resonant frequency, these experiments demonstrate that these effects can be observed at relatively low frequencies as well. Experiments were performed in a thin, quasi-two-dimensional rectangular acrylic box partially filled with 20-cSt PDMS silicone oil with overlying ambient air. The apparatus was subjected to sinusoidal axial vibration that produced breakup of the gas-liquid free surface, producing liquid jets into the air, droplets pinching off from these jets, gas cavities in the liquid from impacts of these droplets, and bubble transport below the interface. Vibration conditions for the attached videos are 280 Hz frequency, 15 g acceleration, and 94 micron peak-to-peak displacement. Behaviors shown in the videos include the following. 1. Free surface breakup into jets and droplets, and...

  6. Structural Interfaces and Attachments in Biology

    CERN Document Server

    Birman, Victor; Genin, Guy

    2013-01-01

    Attachment of dissimilar materials in engineering and surgical practice is a perennial challenge. Bimaterial attachment sites are common locations for injury, repeated injury, and mechanical failure. Nature presents several highly effective solutions to the challenge of bimaterial attachment that differ from those found in engineering practice. Structural Interfaces and Attachments in Biology describes the attachment of dissimilar materials from multiple perspectives. The text will simultaneously elucidate natural bimaterial attachments and outline engineering principles underlying successful attachments to the communities of tissue engineers and surgeons. Included an in-depth analysis of the biology of attachments in the body and mechanisms by which robust attachments are formed, a review of current concepts of attaching dissimilar materials in surgical practice and a discussion of bioengineering approaches that are currently being developed. This book also: Provides the first comprehensive treatment of phys...

  7. Attachment patterns and separation anxiety symptom

    OpenAIRE

    Sakineh - Mofrad; Rohani - Abdullah; Ikechkwu - Uba

    2010-01-01

    Literature suggests that child attachment and anxiety symptoms are related. One purpose of the present study was to assess whether attachment patterns related differently to separation anxiety symptoms (fear of being alone, and fear of abandonment). Three attachment patterns assessed were secure, avoidant and ambivalent attachment. Findings indicated that ambivalent attachment was most consistently related with higher separation anxiety symptom. And also, different associations were found bet...

  8. Bar overdentures utilizing the Locator attachment.

    Science.gov (United States)

    Schneider, A L; Kurtzman, G M

    2001-01-01

    Implant-retained overdentures are a restorative option for both the fully and partially edentulous arches. A new attachment, the Locator, which features a reduced interarch requirement and the advantage of built-in guide planes providing precise insertion, is described. The Locator is an advancement in attachment technology, with an improved design combined from the best features of a ball attachment, an ERA attachment, and a cap attachment.

  9. Monitoring of living cell attachment and spreading using reverse symmetry waveguide sensing

    DEFF Research Database (Denmark)

    Horvath, R.; Pedersen, H.C.; Skivesen, N.;

    2005-01-01

    The effect of the attachment and spreading of living cells on the modes of a grating coupled reverse symmetry waveguide sensor is investigated in real time. The reverse symmetry design has an increased probing depth into the sample making it well suited for the monitoring of cell morphology....... As a result, significant changes in the incoupling peak height and peak shape were observed during cell attachment and spreading. It is suggested that the area under the incoupling peaks reflects the initial cell attachment process, while the mean peak position is mostly governed by the spreading of the cells...

  10. PRECISION ATTACHMENTS; APPLICATIONS AND LIMITATIONS

    Directory of Open Access Journals (Sweden)

    Prabhakar

    2012-12-01

    Full Text Available ABSTRACT: A unique concern of a removable denture when compare d to others is retention. Retention is the ability of the prosthesis to resist the movement of denture away from the supporting tissues/teeth. The component of removable d enture which provides retention is called as direct retainer. 1,3,4 A direct retainer can be either an extracoronal or intracoronal retainer. Extracoronal direct retainer uses mechanical resistance to displa cement through components placed on external surface of abutment teeth. Intracoronal retainer is either cast or attached to tally within the restored natural contours of an abutment tooth. 1 One of the main drawbacks of extracoronal retainers used in partial dentures is visibility. Many patients find themselves in an aest hetically compromised state when these retainers are placed on teeth in visible area. Preci sion attachments provide solution for this problem. Also, precision attachments provide better ve rtical support and better stimulation to the underlying tissue through intermittent vertical massage. 1,9 Although the history of intracoronal retainers goes back to 5 th and 4 th centuries BC, technically more sound developments began in early 2 0 th century AD, with Dr. Herman E. S. Chayes formulating the principle of internal attachme nt in 1906. Since then precision attachments are playing an important role in removabl e and fixed partial denture, conventional and implant supported overdenture. 9

  11. Adult attachment and psychosocial functioning

    NARCIS (Netherlands)

    Pielage, Suzanne Brenda

    2006-01-01

    In the trilogy Attachment, Separation and Loss (1969, 1973, 1980), Bowlby theorized that early experiences with caregivers affect the quality of individuals’ later (romantic) relationships and, consequently, their mental health. The current thesis set out to examine the relationships between adult a

  12. Role of combination vibrations in resonant positron annihilation

    OpenAIRE

    Young, J A; Gribakin, Gleb; Lee, C. M. R.; Surko, C.M.

    2008-01-01

    Positrons can attach to molecules via vibrational Feshbach resonances, leading to very large annihilation rates. The predictions of a recent theory for this process are validated for deuterated methyl halides where all modes are dipole coupled to the incident positron. Data and analysis are presented for methanol and ethylene, demonstrating the importance of combination and overtone resonances and the ability of the theory to account for these features. The mechanism for these resonances and ...

  13. Analiza vibracij gonilnika turbopuhala: An analysis of turbocharger impeller vibrations:

    OpenAIRE

    Sekavčnik, Mihael

    2000-01-01

    The paper presents the results of experimental studies of natural vibrations of turbocharger blades. In order to excite the structure of a turbocharger impeller (composite blade-disc system), impulse disturbance and acoustic harmonic excitation were used. The response of the system was measured using accelerometers attached to the impeller blades. The logaritmic decrement method was used to determine the damping ratio. Measurements showed that the blades are most responsive (the largest ampli...

  14. Surface-Bulk Vibrational Correlation Spectroscopy.

    Science.gov (United States)

    Roy, Sandra; Covert, Paul A; Jarisz, Tasha A; Chan, Chantelle; Hore, Dennis K

    2016-05-01

    Homo- and heterospectral correlation analysis are powerful methods for investigating the effects of external influences on the spectra acquired using distinct and complementary techniques. Nonlinear vibrational spectroscopy is a selective and sensitive probe of surface structure changes, as bulk molecules are excluded on the basis of symmetry. However, as a result of this exquisite specificity, it is blind to changes that may be occurring in the solution. We demonstrate that correlation analysis between surface-specific techniques and bulk probes such as infrared absorption or Raman scattering may be used to reveal additional details of the adsorption process. Using the adsorption of water and ethanol binary mixtures as an example, we illustrate that this provides support for a competitive binding model and adds new insight into a dimer-to-bilayer transition proposed from previous experiments and simulations. PMID:27058265

  15. Vibrational control of electron-transfer reactions: a feasibility study for the fast coherent transfer regime.

    Science.gov (United States)

    Antoniou, P; Ma, Z; Zhang, P; Beratan, D N; Skourtis, S S

    2015-12-14

    Molecular vibrations and electron-vibrational interactions are central to the control of biomolecular electron and energy-transfer rates. The vibrational control of molecular electron-transfer reactions by infrared pulses may enable the precise probing of electronic-vibrational interactions and of their roles in determining electron-transfer mechanisms. This type of electron-transfer rate control is advantageous because it does not alter the electronic state of the molecular electron-transfer system or irreversibly change its molecular structure. For bridge-mediated electron-transfer reactions, infrared (vibrational) excitation of the bridge linking the electron donor to the electron acceptor was suggested as being capable of influencing the electron-transfer rate by modulating the bridge-mediated donor-to-acceptor electronic coupling. This kind of electron-transfer experiment has been realized, demonstrating that bridge-mediated electron-transfer rates can be changed by exciting vibrational modes of the bridge. Here, we use simple models and ab initio computations to explore the physical constraints on one's ability to vibrationally perturb electron-transfer rates using infrared excitation. These constraints stem from the nature of molecular vibrational spectra, the strengths of the electron-vibrational coupling, and the interaction between molecular vibrations and infrared radiation. With these constraints in mind, we suggest parameter regimes and molecular architectures that may enhance the vibrational control of electron transfer for fast coherent electron-transfer reactions.

  16. EFFECT OF PARTICLE SIZE AND PACKING RATIO OF PID ON VIBRATION AMPLITUDE OF BEAM

    OpenAIRE

    P.S. Kachare; Bimleshkumar

    2013-01-01

    Everything in the universe that has mass possesses stiffness and intrinsic damping. Owing to the stiffness property, mass will vibrate when excited and its intrinsic damping property will act to stop the vibration. The particle impact damper (PID) is a very interesting damper that affects impact and friction effects of particles by means of energy dissipation. PID is a means for achieving high structural damping by using a particle-filled enclosure attached to a structure. The particles absor...

  17. Effect of disorder on ultrafast exciton dynamics probed by single molecule spectroscopy

    OpenAIRE

    Hernando, Jordi; van Dijk; Jacob P. Hoogenboom; Garcia-Lopez, Juan José; David N. Reinhoudt; Crego-Calama, Mercedes; Garcia-Parajo, Maria F.; Hulst, van, N.F.

    2006-01-01

    We present a single-molecule study unraveling the effect of static disorder on the vibrational-assisted ultrafast exciton dynamics in multichromophoric systems. For every single complex, we probe the initial exciton relaxation process by an ultrafast pump-probe approach and the coupling to vibrational modes by emission spectra, while fluorescence lifetime analysis measures the amount of static disorder. Exploiting the wide range of disorder found from complex to complex, we demonstrate that s...

  18. An improved fabrication method for carbon nanotube probe

    Institute of Scientific and Technical Information of China (English)

    XU Zong-wei; GUO Li-qiu; DONG Shen; ZHAO Qing-liang

    2008-01-01

    An improved arc discharge method is developed to fabricate the carbon nanotube probe.In this method,the silicon probe and the carbon nanotube were manipulated under an optical microscope.When the silicon probe and the carbon nanotube were very close,30-60 V dc or ac was applied between them,and the carbon nanotube was divided and attached to the end of the silicon probe.Comparing with the arc discharge method,the new method need not coat the silicon probe with metal in advance,which Can greatly reduce the fabrication difficulty and cost.The fabricated carbon nanotube probe exhibits the good property of hish aspect ratio and can reflect the true topography more accurately than the silicon probe.

  19. Performance Study of Diagonally Segmented Piezoelectric Vibration Energy Harvester

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Eun [Catholic Univ. of Daegu, Daegu (Korea, Republic of)

    2013-08-15

    This study proposes a piezoelectric vibration energy harvester composed of two diagonally segmented energy harvesting units. An auxiliary structural unit is attached to the tip of a host structural unit cantilevered to a vibrating base, where the two components have beam axes in opposite directions from each other and matched short-circuit resonant frequencies. Contrary to the usual observations in two resonant frequency-matched structures, the proposed structure shows little eigenfrequency separation and yields a mode sequence change between the first two modes. These lead to maximum power generation around a specific frequency. By using commercial finite element software, it is shown that the magnitude of the output power from the proposed vibration energy harvester can be substantially improved in comparison with those from conventional cantilevered energy harvesters with the same footprint area and magnitude of a tip mass.

  20. Surface Acoustic Wave Vibration Sensors for Measuring Aircraft Flutter

    Science.gov (United States)

    Wilson, William C.; Moore, Jason P.; Juarez, Peter D.

    2016-01-01

    Under NASA's Advanced Air Vehicles Program the Advanced Air Transport Technology (AATT) Project is investigating flutter effects on aeroelastic wings. To support that work a new method for measuring vibrations due to flutter has been developed. The method employs low power Surface Acoustic Wave (SAW) sensors. To demonstrate the ability of the SAW sensor to detect flutter vibrations the sensors were attached to a Carbon fiber-reinforced polymer (CFRP) composite panel which was vibrated at six frequencies from 1Hz to 50Hz. The SAW data was compared to accelerometer data and was found to resemble sine waves and match each other closely. The SAW module design and results from the tests are presented here.

  1. Forced response of a cantilever beam with a dry friction damper attached. I - Theory. II - Experiment

    Science.gov (United States)

    Dowell, E. H.; Schwartz, H. B.

    1983-01-01

    A theoretical and experimental study of the forced vibration response of a cantilevered beam with Coulomb damping nonlinearity is described. Viscous damping in the beam is neglected. Beam and dry friction damper configurations of interest for applications to turbine blade vibrations are considered. It is shown that the basic phenomena found by Dowell (1983) for a simply supported beam with an attached dry friction damper of specific geometry also apply to a cantilevered beam and a more general representation of the dry friction damper and its associated mass and stiffness.

  2. Carbon monoxide dissociative attachment and resonant dissociation by electron-impact

    Science.gov (United States)

    Laporta, V.; Tennyson, J.; Celiberto, R.

    2016-02-01

    Low-energy dissociative electron attachment and resonant electron impact dissociation of CO molecule are considered. Ro-vibrationally resolved cross sections and rate coefficients for both the processes are calculated using an ab-initio model based on the low-lying \\text{X}{{}2}\\Pi resonance of CO-. Final results show that the cross sections increases very rapidly as a function of the ro-vibrational level; these cross sections should be useful for understanding kinetic dissociation of CO in strongly non-equilibrium plasmas.

  3. Electron attachment to SF(6) and lifetimes of SF(6)(-) negative ions

    OpenAIRE

    Gerchikov, L. G.; Gribakin, Gleb

    2008-01-01

    We study the process of low-energy electron capture by the SF(6) molecule. Our approach is based on the model of Gauyacq and Herzenberg [J. P. Gauyacq and A. Herzenberg, J. Phys. B 17, 1155 (1984)] in which the electron motion is coupled to the fully symmetric vibrational mode through a weakly bound or virtual s state. By tuning the two free parameters of the model, we achieve an accurate description of the measured electron attachment cross section and good agreement with vibrational excitat...

  4. Alkyl CH Stretch Vibrations as a Probe of Conformational Preferences

    Science.gov (United States)

    Sibert, Edwin L. Sibert, Iii; Buchanan, Evan G.; Zwier, Timothy S.

    2013-06-01

    Theoretical IR spectra of 1,2-diphenoxyethane (C_6H_5-O-CH_2-CH_2-O-C_6H_5 DPOE) and 1,2-diphenylethane (C_6H_5-CH_2-CH_2-C_6H_5 DPE) are presented and compared to results of single-conformation spectroscopy of jet cooled molecules. The theoretical transition energies and intensites are obtained from a model based on a local mode Hamiltonian that includes all local cubic stretch-bend couplings that are then projected onto the normal modes. The model parameters are obtained from density functional theory methods. Full dimensional calculations are compared to those of reduced dimensions that include anharmonic CH streches Fermi coupled to scissor modes. Excellent agreement is found. Scale factors of select terms in the reduced dimensional Hamiltonian are determined by fitting the theoretical Hamiltonian to the anti DPE spectrum. Using the same scaling, Hamiltonians for other conformers of the above molecules are generated and used to predict structures by comparing to experimentally determined spectra in the alkyl CH stretch region. The level patterns in the resulting spectra are elucidated in terms of the model parameters. The model results are extended to interpret the spectra of more complicated macrocycles containing multiple -CH_2CH_2- ethano bridges such as the dibenzo-15-crown-5 ether and 2,2,2-paracyclophane.

  5. Mechanics of membrane-cytoskeleton attachment in Paramecium

    Science.gov (United States)

    Campillo, C.; Jerber, J.; Fisch, C.; Simoes-Betbeder, M.; Dupuis-Williams, P.; Nassoy, P.; Sykes, C.

    2012-12-01

    In this paper we assess the role of the protein MKS1 (Meckel syndrome type 1) in the cortical membrane mechanics of the ciliated protist Paramecium. This protein is known to be crucial in the process of cilium formation, and we investigate its putative role in membrane-cytoskeleton attachment. Therefore, we compare cells where the gene coding for MKS1 is silenced to wild-type cells. We found that scanning electron microscopy observation of the cell surface reveals a cup-like structure in wild-type cells that is lost in silenced cells. Since this structure is based on the underlying cytoskeleton, one hypothesis to explain this observation is a disruption of membrane attachment to the cytoskeleton in the absence of MKS1 that should affect plasma membrane mechanics. We test this by probing the mechanics of wild-type and silenced cells by micropipette aspiration. Strikingly, we observe that, at the same aspiration pressure, the membrane of silenced cells is easily aspirated by the micropipette whereas that of wild-type cells enters only at a moderate velocity, an effect that suggests a detachment of the membrane from the underlying cytoskeleton in silenced cells. We quantify this detachment by measuring the deformation of the cell cortex and the rate of cell membrane entry in the micropipette. This study offers a new perspective for the characterization of membrane-cytoskeleton attachment in protists and paves the way for a better understanding of the role of membrane-cortex attachment in cilium formation.

  6. Scintillation probe with photomultiplier tube saturation indicator

    Science.gov (United States)

    Ruch, Jeffrey F.; Urban, David J.

    1996-01-01

    A photomultiplier tube saturation indicator is formed by supplying a supplemental light source, typically an light emitting diode (LED), adjacent to the photomultiplier tube. A switch allows the light source to be activated. The light is forwarded to the photomultiplier tube by an optical fiber. If the probe is properly light tight, then a meter attached to the indicator will register the light from the LED. If the probe is no longer light tight, and the saturation indicator is saturated, no signal will be registered when the LED is activated.

  7. Vibrational spectroscopy at high external pressures the diamond anvil cell

    CERN Document Server

    Ferraro, John R

    1984-01-01

    Vibrational Spectroscopy at High External Pressures: The Diamond Anvil Cell presents the effects of high pressure on the vibrational properties of materials as accomplished in a diamond anvil cell (DAC). The DAC serves the dual purpose of generating the pressures and being transparent to infrared radiation, allowing the observation of changes caused by pressure. The optical probes highlighted will deal principally with infrared and Raman scattering, although some observations in the visible region will also be presented. The book begins with a discussion of the effects of pressure and pres

  8. Bound and continuum vibrational states of the bifluoride anion

    Science.gov (United States)

    Špirko, V.; Šindelka, M.; Shirsat, R. N.; Leszczynski, J.

    2003-07-01

    The energies of the bound vibrational states and energy density spectra of the continuum vibrational states of FHF - are calculated, 'exactly' and 'adiabatically', using a new ab initio (CCSD(T)) potential energy surface. Statistical properties of the bound states are probed in terms of the density of states and nearest neighbor level spacing distributions (NNSD). Importantly, the approximate 'adiabatic' densities coincide nearly quantitatively with their 'exact' counterparts. A quantitative fitting of the NNSDs is achieved with a new empirical modification of the Wigner distribution.

  9. Vibrations and waves

    CERN Document Server

    Kaliski, S

    2013-01-01

    This book gives a comprehensive overview of wave phenomena in different media with interacting mechanical, electromagnetic and other fields. Equations describing wave propagation in linear and non-linear elastic media are followed by equations of rheological models, models with internal rotational degrees of freedom and non-local interactions. Equations for coupled fields: thermal, elastic, electromagnetic, piezoelectric, and magneto-spin with adequate boundary conditions are also included. Together with its companion volume Vibrations and Waves. Part A: Vibrations this work provides a wealth

  10. Vibrational spectroscopy of resveratrol

    Science.gov (United States)

    Billes, Ferenc; Mohammed-Ziegler, Ildikó; Mikosch, Hans; Tyihák, Ernő

    2007-11-01

    In this article the authors deal with the experimental and theoretical interpretation of the vibrational spectra of trans-resveratrol (3,5,4'-trihydroxy- trans-stilbene) of diverse beneficial biological activity. Infrared and Raman spectra of the compound were recorded; density functional calculations were carried out resulting in the optimized geometry and several properties of the molecule. Based on the calculated force constants, a normal coordinate analysis yielded the character of the vibrational modes and the assignment of the measured spectral bands.

  11. Man-Induced Vibrations

    DEFF Research Database (Denmark)

    Jönsson, Jeppe; Hansen, Lars Pilegaard

    1994-01-01

    work has been done on the measurement of the exact load functions and related reponse analysis. A recent work using a spectral description has been performed by Per-Erik Erikson and includes a good literature survey. Bachmann and Ammann give a good overview of vibrations caused by human activity. Other...... concerned with spectator-induced vertical vibrations on grandstands. The idea is to use impulse response analysis and base the load description on the load impulse. If the method is feasable, it could be used in connection with the formulation of requirements in building codes. During the last two decades...

  12. Vibration Propagation in Spider Webs

    Science.gov (United States)

    Hatton, Ross; Otto, Andrew; Elias, Damian

    Due to their poor eyesight, spiders rely on web vibrations for situational awareness. Web-borne vibrations are used to determine the location of prey, predators, and potential mates. The influence of web geometry and composition on web vibrations is important for understanding spider's behavior and ecology. Past studies on web vibrations have experimentally measured the frequency response of web geometries by removing threads from existing webs. The full influence of web structure and tension distribution on vibration transmission; however, has not been addressed in prior work. We have constructed physical artificial webs and computer models to better understand the effect of web structure on vibration transmission. These models provide insight into the propagation of vibrations through the webs, the frequency response of the bare web, and the influence of the spider's mass and stiffness on the vibration transmission patterns. Funded by NSF-1504428.

  13. A self-assembled microlensing rotational probe

    OpenAIRE

    Brody, James P; Quake, Stephen R.

    1999-01-01

    A technique to measure microscopic rotational motion is presented. When a small fluorescent polystyrene microsphere is attached to a larger polystyrene microsphere, the larger sphere acts as a lens for the smaller microsphere and provides an optical signal that is a strong function of the azimuthal angle. We demonstrate the technique by measuring the rotational diffusion constant of the microsphere in solutions of varying viscosity and discuss the feasibility of using this probe to measure ro...

  14. Proximal Probes Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Proximal Probes Facility consists of laboratories for microscopy, spectroscopy, and probing of nanostructured materials and their functional properties. At the...

  15. Adult attachment processes: individual and couple perspectives.

    Science.gov (United States)

    Bartholomew, K

    1997-09-01

    This paper overviews a new approach to understanding the range of difficulties experienced in close attachment relationships in adulthood. Drawing on the work of Bowlby, four prototypic adult attachment patterns are defined in terms of the intersection of two underlying dimensions, the positivity of the person's self-image and the positivity of the person's image of others (Bartholomew, 1990; Bartholomew & Horowitz, 1991). The distinct interpersonal difficulties associated with each attachment pattern are described. Findings are presented indicating that individual differences in attachment have implications for the quality of adults' romantic relationships, and that attachment theory may be helpful in understanding violent spousal relationships. Five current issues in the study of adult attachment are addressed: the stability of attachment patterns, the associations between attachment and general personality factors, the relative merits of categorical and prototype assessments of attachment, the identification of multiple attachments in adulthood, and the specificity of adult attachment patterns. It is suggested that the four-category model of adult attachment is especially sensitive to the range and complexity of attachment-related difficulties experienced in adulthood.

  16. Development of vibrating insoles

    NARCIS (Netherlands)

    Hijmans, J.M.; Geertzen, J.H.B.; Schokker, B.; Postema, K.

    2007-01-01

    The objective of this study was to describe the development of vibrating insoles. Insoles, providing a subsensory mechanical noise signal to the plantar side of the feet, may improve balance in healthy young and older people and in patients with stroke or diabetic neuropathy. This study describes th

  17. High-Temperature Vibration Damper

    Science.gov (United States)

    Clarke, Alan; Litwin, Joel; Krauss, Harold

    1987-01-01

    Device for damping vibrations functions at temperatures up to 400 degrees F. Dampens vibrational torque loads as high as 1,000 lb-in. but compact enough to be part of helicopter rotor hub. Rotary damper absorbs energy from vibrating rod, dissipating it in turbulent motion of viscous hydraulic fluid forced by moving vanes through small orifices.

  18. Plate-shaped non-contact ultrasonic transporter using flexural vibration.

    Science.gov (United States)

    Ishii, Takahiko; Mizuno, Yosuke; Koyama, Daisuke; Nakamura, Kentaro; Harada, Kana; Uchida, Yukiyoshi

    2014-02-01

    We developed a plate-shaped non-contact transporter based on ultrasonic vibration, exploiting a phenomenon that a plate can be statically levitated at the place where its gravity and the acoustic radiation force are balanced. In the experiment, four piezoelectric zirconate titanate elements were attached to aluminum plates, on which lattice flexural vibration was excited at 22.3 kHz. The vibrating plates were connected to a loading plate via flexible posts that can minimize the influence of the flexure induced by heavy loads. The distribution of the vibration displacement on the plate was predicted through finite-element analysis to find the appropriate positions of the posts. The maximum levitation height of this transporter was 256 μm with no load. When two vibrating plates were connected to a loading plate, the maximum transportable load was 4.0 kgf. PMID:23876434

  19. Attaching Chuck Keys to Machine Tools

    Science.gov (United States)

    Richardson, V.

    1984-01-01

    Chuck keys attached to portable machine tools by retracting lanyards. Lanyard held taut by recoil caddy attached to tool base. Chuck key available for use when needed and safely secured during operation of tool.

  20. Vibrational Conical Intersections: Implications for Ultrafast Vibrational Dynamics

    Science.gov (United States)

    Dawadi, Mahesh; Prasad Thapaliya, Bishnu; Bhatta, Ram; Perry, David

    2015-03-01

    The presence of conical intersections (CIs) between electronic potential energy surfaces is known to play a key role in ultrafast electronic relaxation in diverse circumstances. Recent reports have documented the existence of vibrational CIs connecting vibrationally adiabatic surfaces. Just as electronic CIs are now appreciated to be ubiquitous, controlling the rates of many photochemical processes, the present work on methanol and methyl mercaptan suggests that vibrational CIs may also be widespread, possibly controlling the outcome of some high-energy processes where vibrationally excited species are present. Other examples of vibrational CIs include the vibrational Jahn-Teller effect in C3V organic molecules and transition metal complexes. While the present work addresses only the couplings within bound molecules, the concept of vibrational CIs providing pathways for ultrafast relaxation also applies to molecular collisions. This work is supported by DOE (DEFG02-90ER14151).

  1. Oxytocin enhances the experience of attachment security

    OpenAIRE

    Buchheim, Anna; Heinrichs, Markus; George, Carol; Pokorny, Dan; Koops, Eva; Henningsen, Peter; O’Connor, Mary-Frances; Gundel, Harald

    2009-01-01

    Repeated interactions between infant and caregiver result in either secure or insecure relationship attachment patterns, and insecure attachment may affect individual emotion-regulation and health. Given that oxytocin enhances social approach behavior in animals and humans, we hypothesized that oxytocin might also promote the experience of attachment security in humans. Within a 3-week interval 26 healthy male students classified with an insecure attachment pattern were invited twice to an ex...

  2. Attachment Theory, Foster Parents and Diversity Tolerance

    OpenAIRE

    Kenny, Michael; Fleming, Ted

    2009-01-01

    relevance to attachment within the biological and foster family. Yet every foster parent has a childhood attachment history that influences their interpersonal relationships in adulthood. The primary concern of the foster parent and their supports is with the foster child. But as a result the foster parent may distract or block reflection on their own attachment history. This presentation will focus on attachment theory and the adult, with particular reference to the foster parent. The pre...

  3. Development of foster mother-child attachment

    OpenAIRE

    Korhonen, J

    2014-01-01

    The impact of early attachment relationships and child-adult attachment relationships to children’s social and emotional development has been recognised for a long time. Since the pioneering attachment theories of John Bowlby and Mary Ainsworth highlighting the importance of secure child-adult attachments, many other theories from various perspectives have risen to fill in the gaps. These theories are examined with the framework of foster care in mind. In Finland, the primary solution fo...

  4. Numerical and Experimental Study of Friction Damping Blade Attachments of Rotating Bladed Disks

    OpenAIRE

    Charleux, D.; Gibert, C; Thouverez, F.; Dupeux, J.

    2006-01-01

    In order to mitigate high cycle fatigue risks in bladed disks, the prediction of the vibration levels early in the design process is important. Therefore, the different sources of damping need to be modeled accurately. In this paper the impact of friction in blade attachments on forced response is investigated both numerically and experimentally. An efficient multiharmonic balance method is proposed in order to compute the forced response of bladed disks with contact and friction nonlineariti...

  5. Effect of Vibration Frequency on Serratus Anterior Muscle Activity during Performance of the Push-up Plus with a Redcord Sling

    OpenAIRE

    Kim, Eui-ryong; Oh, Jae-Seop; Yoo, Won-Gyu

    2014-01-01

    [Purpose] We investigated the effect of vibration at various frequencies on serratus anterior (SA) muscle activity. [Subjects] Ten male subjects were recruited. [Methods] The subjects performed the push-up plus exercise supported by straps above the surface and vertical ropes in the Redcord sling. During the push-up plus, vibrations of 0, 30, 50, or 90 Hz were applied to the Redcord sling using a mechanical vibration apparatus attached to the rope. SA muscle activity was recorded using electr...

  6. 21 CFR 872.3165 - Precision attachment.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Precision attachment. 872.3165 Section 872.3165...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3165 Precision attachment. (a) Identification. A precision attachment or preformed bar is a device made of austenitic alloys or alloys containing 75...

  7. Improved Active Vibration Isolation Systems

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The control force, feedback gain, and actuator stroke of several active vibration isolation systems were analyzed based on a single-layer active vibration isolation system. The analysis shows that the feedback gain and actuator stroke cannot be selected independently and the active isolation system design must make a compromise between the feedback gain and actuator stroke. The performance of active isolation systems can be improved by the joint vibration reduction using an active vibration isolation system with an adaptive dynamic vibration absorber. The results show that the joint vibration reduction method can successfully avoid the compromise between the feedback gain and actuator stroke. The control force and the object vibration amplitude are also greatly reduced.

  8. Probe tip heating assembly

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz, Roger William; Oh, Yunje

    2016-10-25

    A heating assembly configured for use in mechanical testing at a scale of microns or less. The heating assembly includes a probe tip assembly configured for coupling with a transducer of the mechanical testing system. The probe tip assembly includes a probe tip heater system having a heating element, a probe tip coupled with the probe tip heater system, and a heater socket assembly. The heater socket assembly, in one example, includes a yoke and a heater interface that form a socket within the heater socket assembly. The probe tip heater system, coupled with the probe tip, is slidably received and clamped within the socket.

  9. Application of vibrational microspectroscopy to biology and medicine

    OpenAIRE

    Singh, Bhawana; Gautam, Rekha; Kumar, Srividya; Kumar, Vinay BN; Nongthomba, Upendra; Nandi, Dipankar; Mukherjee, Geetashree; Santosh, Vani; Somasundaram, Kumaravel; Umapathy, Siva

    2012-01-01

    Vibrational microspectroscopic (Raman and infrared (IR)) techniques are rapidly emerging as effective tools to probe the basic processes of life. This review mainly focuses on the applications of Raman and IR microspectroscopy to biology and biomedicine, ranging from studies on cellular components in single cells to advancement in techniques for in vitro to in vivo applications. These techniques have proved to be instrumental in studying the biological specimen with minimum perturbation, i.e....

  10. Molecular vibrational energy flow

    Science.gov (United States)

    Gruebele, M.; Bigwood, R.

    This article reviews some recent work in molecular vibrational energy flow (IVR), with emphasis on our own computational and experimental studies. We consider the problem in various representations, and use these to develop a family of simple models which combine specific molecular properties (e.g. size, vibrational frequencies) with statistical properties of the potential energy surface and wavefunctions. This marriage of molecular detail and statistical simplification captures trends of IVR mechanisms and survival probabilities beyond the abilities of purely statistical models or the computational limitations of full ab initio approaches. Of particular interest is IVR in the intermediate time regime, where heavy-atom skeletal modes take over the IVR process from hydrogenic motions even upon X H bond excitation. Experiments and calculations on prototype heavy-atom systems show that intermediate time IVR differs in many aspects from the early stages of hydrogenic mode IVR. As a result, IVR can be coherently frozen, with potential applications to selective chemistry.

  11. Granular Media-Based Tunable Passive Vibration Suppressor

    Science.gov (United States)

    Dillon, Robert P.; Davis, Gregory L.; Shapiro, Andrew A.; Borgonia, John Paul C.; Kahn, Daniel L.; Boechler, Nicholas; Boechler,, Chiara

    2013-01-01

    and vibration suppression device is composed of statically compressed chains of spherical particles. The device superimposes a combination of dissipative damping and dispersive effects. The dissipative damping resulting from the elastic wave attenuation properties of the bulk material selected for the granular media is independent of particle geometry and periodicity, and can be accordingly designed based on the dissipative (or viscoelastic) properties of the material. For instance, a viscoelastic polymer might be selected where broadband damping is desired. In contrast, the dispersive effects result from the periodic arrangement and geometry of particles composing a linear granular chain. A uniform (monatomic) chain of statically compressed spherical particles will have a low-pass filter effect, with a cutoff frequency tunable as a function of particle mass, elastic modulus, Poisson fs ratio, radius, and static compression. Elastic waves with frequency content above this cutoff frequency will exhibit an exponential decay in amplitude as a function of propagation distance. System design targeting a specific application is conducted using a combination of theoretical, computational, and experimental techniques to appropriately select the particle radii, material (and thus elastic modulus and Poisson fs ratio), and static compression to satisfy estimated requirements derived for shock and/or vibration protection needs under particular operational conditions. The selection of a chain of polymer spheres with an elastic modulus .3 provided the appropriate dispersive filtering effect for that exercise; however, different operational scenarios may require the use of other polymers, metals, ceramics, or a combination thereof, configured as an array of spherical particles. The device is a linear array of spherical particles compressed in a container with a mechanism for attachment to the shock and/or vibration source, and a mechanism for attachment to the article requiring

  12. Pickin’ up good vibrations

    CERN Multimedia

    Katarina Anthony

    2015-01-01

    In preparation for the civil engineering work on the HL-LHC, vibration measurements were carried out at the LHC’s Point 1 last month. These measurements will help evaluate how civil engineering work could impact the beam, and will provide crucial details about the site’s geological make-up before construction begins.   A seismic truck at Point 1 generated wave-like vibrations measured by EN/MME. From carrying out R&D to produce state-of-the-art magnets to developing innovative, robust materials capable of withstanding beam impact, the HL-LHC is a multi-faceted project involving many groups and teams across CERN’s departments. It was in this framework that the project management mandated CERN's Mechanical and Materials Engineering (EN/MME) group to measure the propagation of vibrations around Point 1. Their question: can civil engineering work for the HL-LHC – the bulk of which is scheduled for LS2 – begin while the LHC is running? Alth...

  13. Vibrating Rays Theory

    CERN Document Server

    Bilbao, Luis; Minotti, Fernando

    2014-01-01

    The present work is aimed to explain why we started to consider Vibrating Rays Theory (VRT) as a viable representation of nature, and to elaborate some of its consequences. In 1846 Faraday introduced the concept of vibrating rays, in which an atom is conceived as having rays that extend to infinity and move with it. According to this point of view, electromagnetic radiative phenomena correspond to vibration of these rays, which propagate at speed c relative to the rays (and the atom). Although a discussion on this subject might seem to be out-of-date, there are many reasons that justified this debate. The first reason is based on the fact that the constancy of the speed of light, irrespective of the source movement, has not been demonstrated experimentally in a conclusive way. In fact, only ballistic emission theories can be discarded by the experimental results. The second reason is based on the fact that study of radiometric data from spacecrafts indicates the existence of different kinds of anomalous Doppl...

  14. Vibrational stability of graphene

    Directory of Open Access Journals (Sweden)

    Yangfan Hu

    2013-05-01

    Full Text Available The mechanical stability of graphene as temperature rises is analyzed based on three different self-consistent phonon (SCP models. Compared with three-dimensional (3-D materials, the critical temperature Ti at which instability occurs for graphene is much closer to its melting temperature Tm obtained from Monte Carlo simulation (Ti ≃ 2Tm, K. V. Zakharchenko, A. Fasolino, J. H. Los, and M. I. Katsnelson, J. Phys. Condens. Matter 23, 202202. This suggests that thermal vibration plays a significant role in melting of graphene while melting for 3-D materials is often dominated by topologic defects. This peculiar property of graphene derives from its high structural anisotropy, which is characterized by the vibrational anisotropic coefficient (VAC, defined upon its Lindermann ratios in different directions. For any carbon based material with a graphene-like structure, the VAC value must be smaller than 5.4 to maintain its stability. It is also found that the high VAC value of graphene is responsible for its negative thermal expansion coefficient at low temperature range. We believe that the VAC can be regarded as a new criterion concerning the vibrational stability of any low-dimensional (low-D materials.

  15. Multiple cell configuration electromagnetic vibration energy harvester

    International Nuclear Information System (INIS)

    This paper reports the design of an electromagnetic vibration energy harvester that doubles the magnitude of output power generated by the prior four-bar magnet configuration. This enhancement was achieved with minor increase in volume by 23% and mass by 30%. The new 'double cell' design utilizes an additional pair of magnets to create a secondary air gap, or cell, for a second coil to vibrate within. To further reduce the dimensions of the device, two coils were attached to one common cantilever beam. These unique features lead to improvements of 66% in output power per unit volume (power density) and 27% increase in output power per unit volume and mass (specific power density), from 0.1 to 0.17 mW cm-3 and 0.41 to 0.51 mW cm-3 kg-1 respectively. Using the ANSYS multiphysics analysis, it was determined that for the double cell harvester, adding one additional pair of magnets created a small magnetic gradient between air gaps of 0.001 T which is insignificant in terms of electromagnetic damping. An analytical model was developed to optimize the magnitude of transformation factor and magnetic field gradient within the gap.

  16. Piezoelectric energy harvesting from hybrid vibrations

    Science.gov (United States)

    Yan, Zhimiao; Abdelkefi, Abdessattar; Hajj, Muhammad R.

    2014-02-01

    The concept of harvesting energy from ambient and galloping vibrations of a bluff body with a triangular cross-section geometry is investigated. A piezoelectric transducer is attached to the transverse degree of freedom of the body in order to convert these vibrations to electrical energy. A coupled nonlinear distributed-parameter model is developed that takes into consideration the galloping force and moment nonlinearities and the base excitation effects. The aerodynamic loads are modeled using the quasi-steady approximation. Linear analysis is performed to determine the effects of the electrical load resistance and wind speed on the global damping and frequency of the harvester as well as on the onset of instability. Then, nonlinear analysis is performed to investigate the impact of the base acceleration, wind speed, and electrical load resistance on the performance of the harvester and the associated nonlinear phenomena that take place. The results show that, depending on the interaction between the base and galloping excitations, and the considered values of the wind speed, base acceleration, and electrical load resistance, different nonlinear phenomena arise while others disappear. Short- and open-circuit configurations for different wind speeds and base accelerations are assessed. The results show that the maximum levels of harvested power are accompanied by a minimum transverse displacement when varying the electrical load resistance.

  17. Submicron Surface Vibration Profiling Using Doppler Self-Mixing Techniques

    Directory of Open Access Journals (Sweden)

    Tânia Pereira

    2014-01-01

    Full Text Available Doppler self-mixing laser probing techniques are often used for vibration measurement with very high accuracy. A novel optoelectronic probe solution is proposed, based on off-the-shelf components, with a direct reflection optical scheme for contactless characterization of the target’s movement. This probe was tested with two test bench apparatus that enhance its precision performance, with a linear actuator at low frequency (35 µm, 5–60 Hz, and its dynamics, with disc shaped transducers for small amplitude and high frequency (0.6 µm, 100–2500 Hz. The results, obtained from well-established signal processing methods for self-mixing Doppler signals, allowed the evaluation of vibration velocity and amplitudes with an average error of less than 10%. The impedance spectrum of piezoelectric (PZ disc target revealed a maximum of impedance (around 1 kHz for minimal Doppler shift. A bidimensional scan over the PZ disc surface allowed the categorization of the vibration mode (0, 1 and explained its deflection directions. The feasibility of a laser vibrometer based on self-mixing principles and supported by tailored electronics able to accurately measure submicron displacements was, thus, successfully demonstrated.

  18. Self-induced vibration of plane submerged water jets; Nijigen suifunryu no jirei shindo

    Energy Technology Data Exchange (ETDEWEB)

    Sudo, K.; Hibara, H. [Hiroshima University, Hiroshima (Japan). Faculty of Engineering; Shimada, N. [Maritime Safety School, Kyoto (Japan); Harada, M. [Hiroshima University, Hiroshima (Japan); Ishibashi, Y. [Chiba Polytechnic College, Chiba (Japan)

    1999-10-25

    This paper is concerned with an experimental investigation on a self-induced vibration of plane submerged water jets, which occurs, as pointed out in the previous authors' report{sup (10)}, under the condition of a reduced Froude number, Fr{sup *}{identical_to}0.7{approx}1.0 when water jets issue into quiescent water with a free surface. Flow fields are visualized by using injected dye and tracer particles, and interesting data are drawn from the obtained photographs. As the results, it is clarified that the self-induced vibration of water jets is caused by attachment of a jet to a water surface owing to the Coanda effect and branching of a jet at an attachment point, and that the frequency of vibration is independent of water level. (author)

  19. Calculation of bulkhead vibrations in a supported shell simulating a plane fuselage

    Science.gov (United States)

    Efimtsov, B. M.; Lazarev, L. A.

    2014-09-01

    Noise from external sources penetrates a plane cabin through the board construction in several ways. They include direct penetration through loose-fiber layers and indirect penetration through the attachment points of interior panels to transverse ribs (bulkheads). The analytical method of calculating vibrations of an orthogonally supported shell (developed by us earlier) makes it possible to correctly calculate bulkhead vibrations. As a result, noise penetration into the cabin through the attachment points of interior panels can be determined analytically. The first part of the solution to this problem is presented (i.e., the relations and examples of calculating bulkhead vibrations upon point excitation of the shell and excitation by pressure fluctuations of the turbulent boundary layer are given).

  20. Control Application of Piezoelectric Materials to Aeroelastic Self-Excited Vibrations

    Directory of Open Access Journals (Sweden)

    Mohammad Amin Rashidifar

    2014-01-01

    Full Text Available A method for application of piezoelectric materials to aeroelasticity of turbomachinery blades is presented. The governing differential equations of an overhung beam are established. The induced voltage in attached piezoelectric sensors due to the strain of the beam is calculated. In aeroelastic self-excited vibrations, the aerodynamic generalized force of a specified mode can be described as a linear function of the generalized coordinate and its derivatives. This simplifies the closed loop system designed for vibration control of the corresponding structure. On the other hand, there is an industrial interest in measurement of displacement, velocity, acceleration, or a contribution of them for machinery condition monitoring. Considering this criterion in quadratic optimal control systems, a special style of performance index is configured. Utilizing the current relations in an aeroelastic case with proper attachment of piezoelectric elements can provide higher margin of instability and lead to lower vibration magnitude.

  1. Theoretical Analysis of Vibration Frequency of Graphene Sheets Used as Nanomechanical Mass Sensor

    Directory of Open Access Journals (Sweden)

    Toshiaki Natsuki

    2015-09-01

    Full Text Available Nanoelectromechanical resonator sensors based on graphene sheets (GS show ultrahigh sensitivity to vibration. However, many factors such as the layer number and dimension of the GSs will affect the sensor characteristics. In this study, an analytical model is proposed to investigate the vibration behavior of double-layered graphene sheets (DLGSs with attached nanoparticles. Based on nonlocal continuum mechanics, the influences of the layer number, dimensions of the GSs, and of the mass and position of nanoparticles attached to the GSs on the vibration response of GS resonators are discussed in detail. The results indicate that nanomasses can easily be detected by GS resonators, which can be used as a highly sensitive nanomechanical element in sensor systems. A logarithmically linear relationship exists between the frequency shift and the attached mass when the total mass attached to GS is less than about 1.0 zg. Accordingly, it is convenient to use a linear calibration for the calculation and determination of attached nanomasses. The simulation approach and the parametric investigation are useful tools for the design of graphene-based nanomass sensors and devices.

  2. Random vibration movements of liquid nanosized Pb inclusions in Al

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, E.; Andersen, J.S.; Levinsen, M.; Steenstrup, S.; Prokofjev, S.; Zhilin, V.; Dahmen, U.; Radetic, T.; Turner, J.H

    2004-07-15

    Transmission electron microscopy has been used to study the behavior of liquid nanosized Pb inclusions in Al ribbons made by rapid solidification. In situ heating experiments carried out in the temperature range from around 375 to 450 deg. C have shown that liquid inclusions with sizes from around 10-50 nm, that are trapped on dislocations, perform random vibrations around their positions of attachment with vibration periods of some fractions of seconds. The amplitudes of the vibrations in directions perpendicular to the dislocations are a few nanometers, while the motion in directions parallel to the dislocations can be more than an order of magnitude larger. Under conditions where two or more inclusions, attached to a dislocation line, display one-dimensional random motion the inclusions are rarely seen to coalesce. Movement of the inclusions has been monitored by video and shorter sequences have been digitized and analyzed frame-by-frame. The analysis shows that the step lengths have Gaussian distributions indicative of random walks. Fractal analysis of the paths shows that the fractal dimension is close to two which agrees well with the observations that the inclusions carry out linear random walks in a confined space.

  3. THE ORNL ATOM PROBE

    OpenAIRE

    Miller, M

    1986-01-01

    The ORNL Atom Probe is a microanalytical tool for studies in materials science. The instrument is a combination of a customized version of the vacuum system of the VG FIM-100 atom probe, an ORNL-designed microcomputer-controlled digital timing system, and a double curved CEMA Imaging Atom Probe detector. The atom probe combines four instruments into one - namely a field ion microscope, an energy compensated time-of-flight mass spectrometer, an imaging atom probe, and a pulsed laser atom probe.

  4. Mobile Game Probes

    DEFF Research Database (Denmark)

    Borup Lynggaard, Aviaja

    2006-01-01

    This paper will examine how probes can be useful for game designers in the preliminary phases of a design process. The work is based upon a case study concerning pervasive mobile phone games where Mobile Game Probes have emerged from the project. The new probes are aimed towards a specific target...... group and the goal is to specify the probes so they will cover the most relevant areas for our project. The Mobile Game Probes generated many interesting results and new issues occurred, since the probes came to be dynamic and favorable for the process in new ways....

  5. MEASUREMENT OF ADHESION FORCES IN AIR WITH THE VIBRATION METHOD

    Institute of Scientific and Technical Information of China (English)

    Siegfried; Ripperger; Konrad; Hein

    2005-01-01

    The vibration method represents a practical method for the measurement of adhesion forces and adhesion force distributions. This method causes sinusoidally altemating stresses and yields detachment and contact forces between particles and substrate of the same order of magnitude. Alternating contact forces of the vibration method can cause an adhesion force intensification through flattening of asperities. The measuring principle of the vibration method and the analysis of experimental results are described in the article. Normal adhesion forces (pull-off forces) are measured using the vibration method and the colloidal probe technique. The results of both methods show good agreement for small particle sizes. The influence of the detachment force direction is shown by comparing tangential and normal adhesion forces measured using particle reentrainment in a turbulent air flow and the vibration method, respectively. The surface roughness of the substrate and the relative humidity are shown to significantly influence the measured adhesion forces. For the calculation of the adhesion forces, an approach by Rabinovich was combined with approximations of plastic micro asperity flattening. The Rabinovich approach accounts for roughness effects on the van der Waals force by incorporating the rms roughness of the interacting surfaces. rms-values of the particles and substrates were measured with atomic force microscopy at different scanning areas.

  6. Potential of viscous dampers for vibration mitigation of transmission overhead lines

    Science.gov (United States)

    Bassam, A.; Soltani, Amir

    2015-04-01

    One of the important parameters in the design of transmission lines is the evaluation of the susceptibility of these cables to vibrations and if necessary, providing proper means to mitigate these vibrations. Transmission lines are especially susceptible to vibrations as a result of their light weight. Viscous dampers are one of the tools that can be applied to mitigate cable vibrations. However, the damping ratio obtained by these dampers is very limited. The present study provides a finite element formulation for an isoparametric cable element. A comparison is made between the results of presented approach with finite series method to validate the model. Additionally, a comparison is made between linear and non-linear behavior of a cable under sweep sinusoidal excitations with different amplitudes. Finally, a case study is conducted to investigate the potential of additional damping provided by a third viscous damper for the case in which two rubber bushings are already attached to the cable near the anchorages. Based on this case study, the dependency between the third damper location and optimum viscosity for maximum vibration mitigation that can be given to a cable with rubber bushings is investigated. The results of the present study show that although rubber bushings may help mitigating vibrations, they reduce the effect of additional damping devices. Additionally, for non-sagged cables, the nonlinearity is negligible in moderate vibrations. Lastly, if the third damper viscosity is selected properly, it can be very effective in further mitigating the vibrations amplitudes.

  7. VIBRATION ISOLATION SYSTEM PROBABILITY ANALYSIS

    Directory of Open Access Journals (Sweden)

    Smirnov Vladimir Alexandrovich

    2012-10-01

    Full Text Available The article deals with the probability analysis for a vibration isolation system of high-precision equipment, which is extremely sensitive to low-frequency oscillations even of submicron amplitude. The external sources of low-frequency vibrations may include the natural city background or internal low-frequency sources inside buildings (pedestrian activity, HVAC. Taking Gauss distribution into account, the author estimates the probability of the relative displacement of the isolated mass being still lower than the vibration criteria. This problem is being solved in the three dimensional space, evolved by the system parameters, including damping and natural frequency. According to this probability distribution, the chance of exceeding the vibration criteria for a vibration isolation system is evaluated. Optimal system parameters - damping and natural frequency - are being developed, thus the possibility of exceeding vibration criteria VC-E and VC-D is assumed to be less than 0.04.

  8. Computer analysis of railcar vibrations

    Science.gov (United States)

    Vlaminck, R. R.

    1975-01-01

    Computer models and techniques for calculating railcar vibrations are discussed along with criteria for vehicle ride optimization. The effect on vibration of car body structural dynamics, suspension system parameters, vehicle geometry, and wheel and rail excitation are presented. Ride quality vibration data collected on the state-of-the-art car and standard light rail vehicle is compared to computer predictions. The results show that computer analysis of the vehicle can be performed for relatively low cost in short periods of time. The analysis permits optimization of the design as it progresses and minimizes the possibility of excessive vibration on production vehicles.

  9. Attachment theory: A review of research

    Directory of Open Access Journals (Sweden)

    Polovina Nada

    2005-01-01

    Full Text Available Research of attachment is numerous and versatile. They differ according to problems addressed, methodology applied (longitudinal studies, studies with horizontal designs, different instruments used, different methods of data analysis, and characteristics of samples involved (concerning age socio/economic status, family ecology. The research is commonly relied on the core assumptions of the theory itself, and the shared characteristic is orientation to explore complex phenomena of human experience and functioning. From the vast variety of research only those who most directly test the basic assumptions of the attachment theory are focused and addressed in the paper: representation of patterns of attachment in the childhood and adulthood, stability and change of attachment security from infancy to early adulthood, transgenerational transmission of attachment characteristics, the place and the role of attachment behavioral system in the personality development. The aim of the paper is to highlight the basic research and theory issues and directions, and illustrate them with concrete research date.

  10. Wear simulation effects on overdenture stud attachments.

    Science.gov (United States)

    Rutkunas, Vygandas; Mizutani, Hiroshi; Takahashi, Hidekazu; Iwasaki, Naohiko

    2011-01-01

    The aim of this study was to evaluate wear effects on overdenture resilient attachments. Six commercially available attachments were investigated: ERA orange and white (EO and EW), Locator pink, white and blue (LRP, LRW and LRB) and OP anchor (OP). Five specimens were used for wear simulation while other two specimens served as controls. Fifteen thousands insertion-removal cycles were simulated. Dimensional changes and surface characteristics were evaluated using light microscopy and SEM, respectively. Sudden decrease of retentive force was characteristic for EO and EW attachments. Retentive force of Locator attachments fluctuated throughout the wear simulation period. Dimensional changes and surface wear was more expressed on plastic cores than on plastic rings of attachment males. Based on SEM analysis, some of the specimens obtained smoother surface after wear simulation. Mechanism of retention loss of resilient overdenture attachments can be only partially explained by dimensional changes and surface alterations.

  11. Association Between Insecure Attachment and ADHD

    DEFF Research Database (Denmark)

    Storebo, Ole Jakob; Darling Rasmussen, Pernille; Simonsen, Erik

    2016-01-01

    Objective: Psychological theories have postulated an association between insecure attachment and ADHD. The objective of this study is to investigate possible association between insecure attachment and ADHD in children and adults. Method: Review of literature was performed using the Psyc......INFO, Medline, and EMBASE databases. Results: Twenty-nine studies were included in the review. Overall, the studies showed that parental attachment problems and environmental mediating factors were significantly associated with childhood ADHD. Adults with ADHD had a much higher incidence of insecure attachment...... styles than reported in the general population. Conclusion: There seems to be a clear association between ADHD and insecure attachment. It is likely that early intervention in the form of parent training and pharmacological treatment may prevent development of attachment problems. But such studies have...

  12. DESIGN OF THE CONTACT POTENTIALS DIFFERENCE PROBES

    Directory of Open Access Journals (Sweden)

    K. U. Pantsialeyeu

    2016-01-01

    Full Text Available The contact potential difference probes distinguished by great variety and produced mostly in the laboratory for specific experimental applications. As a rule, they consist of commercially available instrumentation, and have a number of disadvantages: large dimensions, complexity and high cost, small sensitivity, operating speed, noiseproof, etc. The purpose of this paper is to describe the basic approaches to design of the small dimension, complete contact potential difference probes, providing high sensitivity, operating speed, and noise immunity. In this paper the contact potential difference probe, which is a electrometer with dynamic capacitor plate at about 0.1–5 mm2 . These probes are could be used in scanning systems, such as a Scanning Kelvin Probe, as well as for controlling system of manufacturing processes, e.g. under friction. The design of such contact potential difference probes conducted using modern electronic components, unique circuitry and design solutions described in detail at paper. The electromechanical modulator applied for mechanical vibrations of the reference sample. To provide a high amplitude and phase stability the upgraded generator with Wien bridge was used instead traditional oscillation sensor. The preamplifier made on the base of modern operational amplifiers with femtoampere current input. The power of the preamplifier designed with «floating ground». It allows keeping the relation constant potential to the probe components when changing over a wide range the compensation voltage. The phase detector-integrator based on the electronic antiphase switches with the modulation frequency of the contact potential difference and the integrator. Fullwave phase detection would greatly increase the sensitivity of the probe. In addition, the application of the phase detection allows suppressing noise and crosstalk at frequencies different from the modulation frequency. The preamplifier and the reference sample

  13. Chaotic vortex induced vibrations

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, J.; Sheridan, J. [Fluids Laboratory for Aeronautical and Industrial Research (FLAIR), Department of Mechanical and Aerospace Engineering, Monash University, Melbourne, Victoria 3800 (Australia); Leontini, J. S. [Department of Mechanical and Product Design Engineering, Swinburne University of Technology, Hawthorn, Victoria 3122 (Australia); Lo Jacono, D. [Institut de Mécanique des Fluides de Toulouse (IMFT), CNRS, UPS and Université de Toulouse, 31400 Toulouse (France)

    2014-12-15

    This study investigates the nature of the dynamic response of an elastically mounted cylinder immersed in a free stream. A novel method is utilized, where the motion of the body during a free vibration experiment is accurately recorded, and then a second experiment is conducted where the cylinder is externally forced to follow this recorded trajectory. Generally, the flow response during both experiments is identical. However, particular regimes exist where the flow response is significantly different. This is taken as evidence of chaos in these regimes.

  14. Lattice Vibrations in Chlorobenzenes:

    DEFF Research Database (Denmark)

    Reynolds, P. A.; Kjems, Jørgen; White, J. W.

    1974-01-01

    Lattice vibrational dispersion curves for the ``intermolecular'' modes in the triclinic, one molecule per unit cell β phase of p‐C6D4Cl2 and p‐C6H4Cl2 have been obtained by inelastic neutron scattering. The deuterated sample was investigated at 295 and at 90°K and a linear extrapolation to 0°K...... by consideration of electrostatic forces or by further anisotropy in the dispersion forces not described in the atom‐atom model. Anharmonic effects are shown to be large, but the dominant features in the temperature variation of frequencies are describable by a quasiharmonic model....

  15. Structural Acoustics and Vibrations

    Science.gov (United States)

    Chaigne, Antoine

    This structural chapter is devoted to vibrations of structures and to their coupling with the acoustic field. Depending on the context, the radiated sound can be judged as desirable, as is mostly the case for musical instruments, or undesirable, like noise generated by machinery. In architectural acoustics, one main goal is to limit the transmission of sound through walls. In the automobile industry, the engineers have to control the noise generated inside and outside the passenger compartment. This can be achieved by means of passive or active damping. In general, there is a strong need for quieter products and better sound quality generated by the structures in our daily environment.

  16. Nonlinear interferometric vibrational imaging

    CERN Document Server

    Marks, D L

    2003-01-01

    Coherent Anti-Stokes Raman Scattering (CARS) processes are ``coherent,'' but the phase of the anti-Stokes radiation is usually lost by most incoherent spectroscopic CARS measurements. We propose a novel Raman microscopy imaging method called Nonlinear Interferometric Vibrational Imaging, which measures Raman spectra by obtaining the temporal anti-Stokes signal through nonlinear interferometry. With a more complete knowledge of the anti-Stokes signal, we show through simulations that a high-resolution Raman spectrum can be obtained of a molecule in a single pulse using broadband radiation. This could be useful for identifying the three-dimensional spatial distribution of molecular species in tissue.

  17. Anharmonic vibrations in nuclei

    CERN Document Server

    Fallot, M; Andrés, M V; Catara, F; Lanza, E G; Scarpaci, J A; Chomaz, Ph.

    2003-01-01

    In this letter, we show that the non-linearitites of large amplitude motions in atomic nuclei induce giant quadrupole and monopole vibrations. As a consequence, the main source of anharmonicity is the coupling with configurations including one of these two giant resonances on top of any state. Two-phonon energies are often lowered by one or two MeV because of the large matrix elements with such three phonon configurations. These effects are studied in two nuclei, 40Ca and 208Pb.

  18. Emergence of tempered preferential attachment from optimization

    OpenAIRE

    D'Souza, Raissa M.; Borgs, Christian; Chayes, Jennifer T.; Berger, Noam; Kleinberg, Robert D.

    2007-01-01

    We show how preferential attachment can emerge in an optimization framework, resolving a long-standing theoretical controversy. We also show that the preferential attachment model so obtained has two novel features, saturation and viability, which have natural interpretations in the underlying network and lead to a power-law degree distribution with exponential cutoff. Moreover, we consider a generalized version of this preferential attachment model with independent saturation and viability, ...

  19. Explaining gender differences in preschoolers’ attachment style

    OpenAIRE

    Tønnessen, Ellen

    2014-01-01

    Gender has throughout most attachment literature not been considered an important factor in the development of individual differences in attachment. However, some studies on preschoolers, especially using story completion/narrative measures of attachment representations, have found prominent gender differences. The present study aims to replicate such gender differences, and to examine possible explanatory variables. This will be done by using a large community sample of preschoolers from Nor...

  20. Attachment theory: Old and new approach

    Directory of Open Access Journals (Sweden)

    Polovina Nada

    2005-01-01

    Full Text Available The article is an attempt to present holistically the key concepts of attachment theory rediscovered for its potentials. The presented concepts include: narrow definition of attachment, behavioral control system of attachment, attachment working model and patterns of attachment. The concepts are presented in the context of child attachment theory and adult attachment theory, in addition to description of the development of attachment. Concepts, as well as developmental processes are presented from the stand point of pioneers in this field (John Bowlby and Mary Ainsworth as well as from the standpoint of their successors (Everett Waters and Malcolm West. Compacted ness of the theory, possibilities for operationalization of its key concepts and its application to empirical studies of complex psychological issues that have never been scientifically explored, makes it a very prospective theory in view of possible integration of existing research findings and initiating new research and new practices in psychotherapy, social work and work in schools. The goal of this integral presentation of attachment theory is to highlight its benefits and possibilities for understanding and research complex field of human's psychosocial functioning.

  1. Oxytocin enhances the experience of attachment security

    Science.gov (United States)

    Buchheim, Anna; Heinrichs, Markus; George, Carol; Pokorny, Dan; Koops, Eva; Henningsen, Peter; O’Connor, Mary-Frances; Gundel, Harald

    2011-01-01

    Summary Repeated interactions between infant and caregiver result in either secure or insecure relationship attachment patterns, and insecure attachment may affect individual emotion-regulation and health. Given that oxytocin enhances social approach behavior in animals and humans, we hypothesized that oxytocin might also promote the experience of attachment security in humans. Within a 3-week interval 26 healthy male students classified with an insecure attachment pattern were invited twice to an experimental session. Within each session, a single dose of oxytocin or placebo was administered, using a double-blind, placebo-controlled within-subject design. In both conditions, subjects completed an attachment task based on the Adult Attachment Projective Picture System (AAP). Thirty-two AAP picture system presentations depicted attachment-related events (e.g. illness, solitude, separation, loss), and were each accompanied by four prototypical phrases representing one secure and three insecure attachment categories. In the oxytocin condition, a significant proportion of these insecure subjects (N = 18; 69%) changed their rankings of “secure attachment” phrases towards the more appropriate for the AAP picture presentation, and the same subjects decreased in overall rating of the “insecure attachment” phrases. In particular, there was a significant decrease in the number of subjects ranking the pictures with “insecure-preoccupied” phrases from the placebo to the oxytocin condition. We find that a single dose of intranasally administered oxytocin is sufficient to induce a significant increase in the experience of attachment security in adults classified previously as insecure. PMID:19457618

  2. Sine-Bar Attachment For Machine Tools

    Science.gov (United States)

    Mann, Franklin D.

    1988-01-01

    Sine-bar attachment for collets, spindles, and chucks helps machinists set up quickly for precise angular cuts that require greater precision than provided by graduations of machine tools. Machinist uses attachment to index head, carriage of milling machine or lathe relative to table or turning axis of tool. Attachment accurate to 1 minute or arc depending on length of sine bar and precision of gauge blocks in setup. Attachment installs quickly and easily on almost any type of lathe or mill. Requires no special clamps or fixtures, and eliminates many trial-and-error measurements. More stable than improvised setups and not jarred out of position readily.

  3. Attachment fixation of the overdenture: part II.

    Science.gov (United States)

    Mensor, M C

    1978-01-01

    Many attachment systems of the bar or stud type increase the stability of an overdenture. When selecting an attachment it is essential to consider the skill of the dentist-laboratory team as well as the dexterity of the patient and to use the easiest system that will still improve stabilization. Generally simplicity in design, ease of maintenance, and minimum leverage should be paramount considerations in selection. Use of a guide such as the EM Gauge and of the EM Attachment Selector significantly reduces the confusion in selecting attachments and increases the working armamentarium for stabilizing an overdenture. PMID:340660

  4. Overdenture locator attachments for atrophic mandible.

    Science.gov (United States)

    Mahajan, Neerja; Thakkur, Rahul K

    2013-10-01

    Implant-supported overdentures provide a good opportunity for dentists to improve oral health and quality-of-life of patients. Atrophic mandible poses a significant challenge to successful oral rehabilitation with dental implants. In this article, the fabrication of lower overdenture by two narrow platform implants is described with dual retentive, resilient, self-locating locator attachment system. The locator attachment system has the lowest profile in comparison with the ball and bar attachments and is versatile up to 40° of divergence between two implants. By using locators as attachments, we can meet functional, economic and social expectation of patients with ease and satisfaction.

  5. Overdenture locator attachments for atrophic mandible

    Directory of Open Access Journals (Sweden)

    Neerja Mahajan

    2013-01-01

    Full Text Available Implant-supported overdentures provide a good opportunity for dentists to improve oral health and quality-of-life of patients. Atrophic mandible poses a significant challenge to successful oral rehabilitation with dental implants. In this article, the fabrication of lower overdenture by two narrow platform implants is described with dual retentive, resilient, self-locating locator attachment system. The locator attachment system has the lowest profile in comparison with the ball and bar attachments and is versatile up to 40΀ of divergence between two implants. By using locators as attachments, we can meet functional, economic and social expectation of patients with ease and satisfaction.

  6. Development of X-ray mini-probes for the Digiray RGX system

    International Nuclear Information System (INIS)

    We have developed and tested a variety of X-ray mini-probes for the Reverse Geometry X-radiography trademark,1 (RGX) system each having their own advantages and disadvantages. These mini-probes consist of small scintillators (as small as 2 mm in diameter and 5 mm long) attached to optical light guides (as long as 14 m) coupled to photomultipliers. Images produced with these probes show that even smaller probes and/or longer light guides may be fashioned. Such probes may be useful in both non-destructive evaluation and medical imaging. ((orig.))

  7. Ultrathin lensed fiber-optic probe for optical coherence tomography.

    Science.gov (United States)

    Qiu, Y; Wang, Y; Belfield, K D; Liu, X

    2016-06-01

    We investigated and validated a novel method to develop ultrathin lensed fiber-optic (LFO) probes for optical coherence tomography (OCT) imaging. We made the LFO probe by attaching a segment of no core fiber (NCF) to the distal end of a single mode fiber (SMF) and generating a curved surface at the tip of the NCF using the electric arc of a fusion splicer. The novel fabrication approach enabled us to control the length of the NCF and the radius of the fiber lens independently. By strategically choosing these two parameters, the LFO probe could achieve a broad range of working distance and depth of focus for different OCT applications. A probe with 125μm diameter and lateral resolution up to 10μm was demonstrated. The low-cost, disposable and robust LFO probe is expected to have great potential for interstitial OCT imaging. PMID:27375934

  8. Ultrathin lensed fiber-optic probe for optical coherence tomography.

    Science.gov (United States)

    Qiu, Y; Wang, Y; Belfield, K D; Liu, X

    2016-06-01

    We investigated and validated a novel method to develop ultrathin lensed fiber-optic (LFO) probes for optical coherence tomography (OCT) imaging. We made the LFO probe by attaching a segment of no core fiber (NCF) to the distal end of a single mode fiber (SMF) and generating a curved surface at the tip of the NCF using the electric arc of a fusion splicer. The novel fabrication approach enabled us to control the length of the NCF and the radius of the fiber lens independently. By strategically choosing these two parameters, the LFO probe could achieve a broad range of working distance and depth of focus for different OCT applications. A probe with 125μm diameter and lateral resolution up to 10μm was demonstrated. The low-cost, disposable and robust LFO probe is expected to have great potential for interstitial OCT imaging.

  9. Displacements analysis of self-excited vibrations in turning

    CERN Document Server

    Bisu, Claudiu-Florinel; Gérard, Alain; K'Nevez, Jean-Yves; 10.1007/s00170-08-1815-8

    2009-01-01

    The actual research deals with determining by a new protocol the necessary parameters considering a three-dimensional model to simulate in a realistic way the turning process on machine tool. This paper is dedicated to the experimental displacements analysis of the block tool / block workpiece with self-excited vibrations. In connexion with turning process, the self-excited vibrations domain is obtained starting from spectra of two accelerometers. The existence of a displacements plane attached to the tool edge point is revealed. This plane proves to be inclined compared to the machines tool axes. We establish that the tool tip point describes an ellipse. This ellipse is very small and can be considered as a small straight line segment for the stable cutting process (without vibrations). In unstable mode (with vibrations) the ellipse of displacements is really more visible. A difference in phase occurs between the tool tip displacements on the radial direction and on the cutting one. The feed motion direction...

  10. Model reduction and analysis of a vibrating beam microgyroscope

    KAUST Repository

    Ghommem, Mehdi

    2012-05-08

    The present work is concerned with the nonlinear dynamic analysis of a vibrating beam microgyroscope composed of a rotating cantilever beam with a tip mass at its end. The rigid mass is coupled to two orthogonal electrodes in the drive and sense directions, which are attached to the rotating base. The microbeam is driven by an AC voltage in the drive direction, which induces vibrations in the orthogonal sense direction due to rotation about the microbeam axis. The electrode placed in the sense direction is used to measure the induced motions and extract the underlying angular speed. A reduced-order model of the gyroscope is developed using the method of multiple scales and used to examine its dynamic behavior. © The Author(s) 2012 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  11. A principle of similarity for nonlinear vibration absorbers

    CERN Document Server

    Habib, Giuseppe

    2016-01-01

    This paper develops a principle of similarity for the design of a nonlinear absorber, the nonlinear tuned vibration absorber (NLTVA), attached to a nonlinear primary system. Specifically, for effective vibration mitigation, we show that the NLTVA should feature a nonlinearity possessing the same mathematical form as that of the primary system. A compact analytical formula for the nonlinear coefficient of the absorber is then derived. The formula, valid for any polynomial nonlinearity in the primary system, is found to depend only on the mass ratio and on the nonlinear coefficient of the primary system. When the primary system comprises several polynomial nonlinearities, we demonstrate that the NLTVA obeys a principle of additivity, i.e., each nonlinear coefficient can be calculated independently of the other nonlinear coefficients using the proposed formula.

  12. Characterisation of vibration input to flywheel used on urban bus

    Science.gov (United States)

    Wang, L.; Kanarachos, S.; Christensen, J.

    2016-09-01

    Vibration induced from road surface has an impact on the durability and reliability of electrical and mechanical components attached on the vehicle. There is little research published relevant to the durability assessment of a flywheel energy recovery system installed on city and district buses. Relevant international standards and legislations were reviewed and large discrepancy was found among them, in addition, there are no standards exclusively developed for kinetic energy recovery systems on vehicles. This paper describes the experimentation of assessment of road surface vibration input to the flywheel on a bus as obtained at the MIRA Proving Ground. Power density spectra have been developed based on the raw data obtained during the experimentation. Validation of this model will be carried out using accelerated life time tests that will be carried out on a shaker rig using an accumulated profile based on the theory of fatigue damage equivalence in time and frequency domain aligned with the model predictions.

  13. Contact resonances of U-shaped atomic force microscope probes

    Energy Technology Data Exchange (ETDEWEB)

    Rezaei, E.; Turner, J. A., E-mail: jaturner@unl.edu [Mechanical and Materials Engineering, University of Nebraska-Lincoln, W342 Nebraska Hall, Lincoln, Nebraska 68588 (United States)

    2016-01-21

    Recent approaches used to characterize the elastic or viscoelastic properties of materials with nanoscale resolution have focused on the contact resonances of atomic force microscope (CR-AFM) probes. The experiments for these CR-AFM methods involve measurement of several contact resonances from which the resonant frequency and peak width are found. The contact resonance values are then compared with the noncontact values in order for the sample properties to be evaluated. The data analysis requires vibration models associated with the probe during contact in order for the beam response to be deconvolved from the measured spectra. To date, the majority of CR-AFM research has used rectangular probes that have a relatively simple vibration response. Recently, U-shaped AFM probes have created much interest because they allow local sample heating. However, the vibration response of these probes is much more complex such that CR-AFM is still in its infancy. In this article, a simplified analytical model of U-shaped probes is evaluated for contact resonance applications relative to a more complex finite element (FE) computational model. The tip-sample contact is modeled using three orthogonal Kelvin-Voigt elements such that the resonant frequency and peak width of each mode are functions of the contact conditions. For the purely elastic case, the frequency results of the simple model are within 8% of the FE model for the lowest six modes over a wide range of contact stiffness values. Results for the viscoelastic contact problem for which the quality factor of the lowest six modes is compared show agreement to within 13%. These results suggest that this simple model can be used effectively to evaluate CR-AFM experimental results during AFM scanning such that quantitative mapping of viscoelastic properties may be possible using U-shaped probes.

  14. Contact resonances of U-shaped atomic force microscope probes

    International Nuclear Information System (INIS)

    Recent approaches used to characterize the elastic or viscoelastic properties of materials with nanoscale resolution have focused on the contact resonances of atomic force microscope (CR-AFM) probes. The experiments for these CR-AFM methods involve measurement of several contact resonances from which the resonant frequency and peak width are found. The contact resonance values are then compared with the noncontact values in order for the sample properties to be evaluated. The data analysis requires vibration models associated with the probe during contact in order for the beam response to be deconvolved from the measured spectra. To date, the majority of CR-AFM research has used rectangular probes that have a relatively simple vibration response. Recently, U-shaped AFM probes have created much interest because they allow local sample heating. However, the vibration response of these probes is much more complex such that CR-AFM is still in its infancy. In this article, a simplified analytical model of U-shaped probes is evaluated for contact resonance applications relative to a more complex finite element (FE) computational model. The tip-sample contact is modeled using three orthogonal Kelvin-Voigt elements such that the resonant frequency and peak width of each mode are functions of the contact conditions. For the purely elastic case, the frequency results of the simple model are within 8% of the FE model for the lowest six modes over a wide range of contact stiffness values. Results for the viscoelastic contact problem for which the quality factor of the lowest six modes is compared show agreement to within 13%. These results suggest that this simple model can be used effectively to evaluate CR-AFM experimental results during AFM scanning such that quantitative mapping of viscoelastic properties may be possible using U-shaped probes

  15. Detection of protease and protease activity using a single nanoscrescent SERS probe

    Science.gov (United States)

    Liu, Gang L.; Ellman, Jonathan A.; Lee, Luke P.; Chen, Fanqing Frank

    2013-01-29

    This invention pertains to the in vitro detection of proteases using a single peptide-conjugate nanocrescent surface enhanced Raman scattering (SERS) probes with at least nanomolar sensitivity. The probe enables detection of proteolytic activity in extremely small volume and at low concentration. In certain embodiments the probes comprise an indicator for the detection of an active protease, where the indicator comprises a nanocrescent attached to a peptide, where said peptide comprises a recognition site for the protease and a Raman tag attached to the peptide.

  16. Measurement of the Resonant Characteristics of a Single Bubble Vibration by Using a Laser Doppler Vibrometer

    Science.gov (United States)

    Yoshikawa, Taisuke; Kotera, Hironori; Yoshida, Kenji; Koyama, Daisuke; Nakamura, Kentaro; Watanabe, Yoshiaki

    2011-07-01

    We constructed the experimental system with a laser Doppler vibrometer (LDV) for measuring the vibration of a single microbubble. It was demonstrated that the system enabled the capture of the vibration with an amplitude of nanometer order. We attempted to experimentally measure the resonant characteristics of a bubble attached to a wall by using the system. As a result, we succeeded in measuring the characteristics and evaluating the Q factor and the resonant radius at a driving frequency of 27.8 kHz, although these values are different from those predicted on the basis of the theory for a single free bubble. The LDV measurement system is expected to an effective tool for evaluating bubble vibrations with very small displacement amplitudes, such as the vibration of a microcapsule.

  17. Experimental investigation of the flow-induced vibration of hydrofoils in cavitating flows

    Science.gov (United States)

    Wang, Guoyu; Wu, Qin; Huang, Biao; Gao, Yuan

    2015-12-01

    The objective of this paper is to investigate the correlation between fluid induced vibration and unsteady cavitation behaviours. Experimental results are presented for a modified NACA66 hydrofoil, which is fixed at α=8°. The high-speed camera is synchronized with a single point Laser Doppler Vibrometer to analyze the transient cavitating flow structures and the corresponding structural vibration characteristics. The results showed that, with the decreasing of the cavitation number, the cavitating flows in a water tunnel display several types of cavitation patterns, such as incipient cavitation, sheet cavitation and cloud cavitation. The cavity shedding frequency reduces with the decrease of the cavitation number. As for the cloud cavitation regime, the trend of the vibration velocity goes up with the growth of the attached cavity, accompanied with small amplitude fluctuations. Then the collapse and shedding of the large-scale cloud cavities leads to substantial increase of the vibration velocity fluctuations.

  18. Study on thermally induced vibration of flexible boom in various thermal environments of vacuum chamber

    Science.gov (United States)

    Kong, Changduk; Oh, Kyung-Won; Park, Hyun-Bum; Sugiyama, Y.

    2005-02-01

    In order to simulate the thermally-induced vibration phenomenon of the flexible thin boom structure of the spacecraft such as the thin solar panel and the flexible cantilever with the attached tip mass in space, the thermally-induced vibration including thermal flutter of the flexible thin boom with the concentrated tip mass was experimentally investigated at various thermal environments using a heat lamp and both vacuum and air condition using the vacuum chamber. In this experimental study, divergence speed, natural frequency and thermal strains of the thermally-induced vibration were comparatively evaluated at various thermal environment conditions. Finally the thermally-induced vibration of the flexible boom structure of the earth orbit satellite in solar radiation environment from the earth eclipse region including umbra and penumbra was simulated using the vacuum chamber and power control of the heating lamp.

  19. Fatigue life evaluation of mechanical components using vibration fatigue analysis technique

    International Nuclear Information System (INIS)

    Unit brackets attached on a cross member and subjected to random loads often fail due to self-vibration. To prevent such failures, it is necessary to understand the fatigue failure mode and to evaluate the fatigue life using test or analysis techniques. The objective of this study is to develop test specifications for components, which are applicable to predict fatigue life at the stage of initial product design, for the unit brackets by using a vibration fatigue technique. For this objective, the necessity of a fatigue analysis considering resonant effect was reviewed. Also, a series of vibration fatigue analyses were carried out by changing the acceleration's direction and magnitude. Then, a methodology was proposed to determine the optimum vibration fatigue test specification of the component, which gives an equivalent failure mode with the vehicle test condition

  20. Development of Fluorescent Protein Probes Specific for Parallel DNA and RNA G-Quadruplexes.

    Science.gov (United States)

    Dang, Dung Thanh; Phan, Anh Tuân

    2016-01-01

    We have developed fluorescent protein probes specific for parallel G-quadruplexes by attaching cyan fluorescent protein to the G-quadruplex-binding motif of the RNA helicase RHAU. Fluorescent probes containing RHAU peptide fragments of different lengths were constructed, and their binding to G-quadruplexes was characterized. The selective recognition and discrimination of G-quadruplex topologies by the fluorescent protein probes was easily detected by the naked eye or by conventional gel imaging.

  1. 14 CFR 33.43 - Vibration test.

    Science.gov (United States)

    2010-01-01

    ... Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: AIRCRAFT ENGINES Block Tests; Reciprocating Aircraft Engines § 33.43 Vibration test. (a) Each engine must undergo a vibration survey to establish the torsional and bending vibration...

  2. Biliprotein maturation: the chromophore attachment.

    Science.gov (United States)

    Scheer, H; Zhao, K-H

    2008-04-01

    Biliproteins are a widespread group of brilliantly coloured photoreceptors characterized by linear tetrapyrrolic chromophores, bilins, which are covalently bound to the apoproteins via relatively stable thioether bonds. Covalent binding stabilizes the chromoproteins and is mandatory for phycobilisome assembly; and, it is also important in biliprotein applications such as fluorescence labelling. Covalent binding has, on the other hand, also considerably hindered biliprotein research because autocatalytic chromophore additions are rare, and information on enzymatic addition by lyases was limited to a single example, an EF-type lyase attaching phycocyanobilin to cysteine-alpha84 of C-phycocyanin. The discovery of new activities for the latter lyases, and of new types of lyases, have reinvigorated research activities in the subject. So far, work has mainly concentrated on cyanobacterial phycobiliproteins. Methodological advances in the process, however, as well as the finding of often large numbers of homologues, opens new possibilities for research on the subsequent assembly/disassembly of the phycobilisome in cyanobacteria and red algae, on the assembly and organization of the cryptophyte light-harvesting system, on applications in basic research such as protein folding, and on the use of phycobiliproteins for labelling.

  3. Coexistence in preferential attachment networks

    CERN Document Server

    Antunović, Tonći; Racz, Miklos Z

    2013-01-01

    Competition in markets is ubiquitous: cell-phone providers, computer manufacturers, and sport gear brands all vie for customers. Though several coexisting competitors are often observed in empirical data, many current theoretical models of competition on small-world networks predict a single winner taking over the majority of the network. We introduce a new model of product adoption that focuses on word-of-mouth recommendations to provide an explanation for this coexistence of competitors. The key property of our model is that customer choices evolve simultaneously with the network of customers. When a new node joins the network, it chooses neighbors according to preferential attachment, and then chooses its type based on the number of initial neighbors of each type. This can model a new cell-phone user choosing a cell-phone provider, a new student choosing a laptop, or a new athletic team member choosing a gear provider. We provide a detailed analysis of the new model; in particular, we determine the possibl...

  4. Hamiltonian dynamics of preferential attachment

    International Nuclear Information System (INIS)

    Prediction and control of network dynamics are grand-challenge problems in network science. The lack of understanding of fundamental laws driving the dynamics of networks is among the reasons why many practical problems of great significance remain unsolved for decades. Here we study the dynamics of networks evolving according to preferential attachment (PA), known to approximate well the large-scale growth dynamics of a variety of real networks. We show that this dynamics is Hamiltonian, thus casting the study of complex networks dynamics to the powerful canonical formalism, in which the time evolution of a dynamical system is described by Hamilton’s equations. We derive the explicit form of the Hamiltonian that governs network growth in PA. This Hamiltonian turns out to be nearly identical to graph energy in the configuration model, which shows that the ensemble of random graphs generated by PA is nearly identical to the ensemble of random graphs with scale-free degree distributions. In other words, PA generates nothing but random graphs with power-law degree distribution. The extension of the developed canonical formalism for network analysis to richer geometric network models with non-degenerate groups of symmetries may eventually lead to a system of equations describing network dynamics at small scales. (paper)

  5. Vibrations and Stability: Solved Problems

    DEFF Research Database (Denmark)

    Thomsen, Jon Juel

    Worked out solutions for exercise problems in J. J. Thomsen 'Vibrations and Stability: Advanced Theory, Analysis, and Tools', Springer, Berlin - Heidelberg, 2003.......Worked out solutions for exercise problems in J. J. Thomsen 'Vibrations and Stability: Advanced Theory, Analysis, and Tools', Springer, Berlin - Heidelberg, 2003....

  6. The study of eccentric vibrator

    International Nuclear Information System (INIS)

    The developed mathematical model of the motion of the eccentric vibrator allowed to define two own frequencies of oscillations of the mechanical system. To confirm the nominated theoretical positions, the motion of the eccentric vibrator is simulated with the aid of the ADAMS (Automated Dynamic Analysis of Mechanical Systems) software complex

  7. Measuring Patients’ Attachment Avoidance in Psychotherapy: Development of the Attachment Avoidance in Therapy Scale (AATS

    Directory of Open Access Journals (Sweden)

    András Láng

    2012-11-01

    Full Text Available A new scale measuring patient-therapist attachment avoidance was developed. Attachment Avoidance in Therapy Scale is a new measure based on the Bartholomew model of adult attachment (Bartholomew & Horowitz, 1991 and the Experience in Close Relationships Scale (Brennan, Clark, & Shaver, 1998 to measure patients’ attachment avoidance towards therapists. With 112 patient-therapist dyads participating in the study, validation of a preliminary scale – measuring both attachment anxiety and attachment avoidance in therapy – took place using therapists’ evaluations of patients’ relational behavior and patients’ self-reports about their attitude toward psychotherapy. Analysis of the data revealed six underlying scales. Results showed all six scales to be reliable. Validation of scales measuring attachment anxiety failed. The importance of Attachment Avoidance in Therapy Scale and its subscales is discussed.

  8. Traversing probe system

    International Nuclear Information System (INIS)

    This invention comprises a rotatable annular probe-positioner which carries at least one radially disposed sensing probe, such as a Pitot tube having a right-angled tip. The positioner can be coaxially and rotatably mounted within a compressor casing or the like and then actuated to orient the sensing probe as required to make measurements at selected stations in the annulus between the positioner and compressor casing. The positioner can be actuated to (a) selectively move the probe along its own axis, (b) adjust the yaw angle of the right-angled probe tip, and (c) revolve the probe about the axis common to the positioner and casing. A cam plate engages a cam-follower portion of the probe and normally rotates with the positioner. The positioner includes a first-motor-driven ring gear which effects slidable movement of the probe by rotating the positioner at a time when an external pneumatic cylinder is actuated to engage the cam plate and hold it stationary. When the pneumatic cylinder is not actuated, this ring gear can be driven to revolve the positioner and thus the probe to a desired circumferential location about the above-mentioned common axis. A second motor-driven ring gear included in the positioner can be driven to rotate the probe about its axis, thus adjusting the yaw angle of the probe tip. The positioner can be used in highly corrosive atmosphere, such as gaseous uranium hexafluoride. 10 claims, 6 figures

  9. The origins of vibration theory

    Science.gov (United States)

    Dimarogonas, A. D.

    1990-07-01

    The Ionian School of natural philosophy introduced the scientific method of dealing with natural phenomena and the rigorous proofs for abstract propositions. Vibration theory was initiated by the Pythagoreans in the fifth century BC, in association with the theory of music and the theory of acoustics. They observed the natural frequency of vibrating systems and proved that it is a system property and that it does not depend on the excitation. Pythagoreans determined the fundamental natural frequencies of several simple systems, such as vibrating strings, pipes, vessels and circular plates. Aristoteles and the Peripatetic School founded mechanics and developed a fundamental understanding of statics and dynamics. In Alexandrian times there were substantial engineering developments in the field of vibration. The pendulum as a vibration, and probably time, measuring device was known in antiquity, and was further developed by the end of the first millennium AD.

  10. An Attachment Model of University Connectedness

    Science.gov (United States)

    Wilson, Steffen; Gore, Jonathan

    2013-01-01

    Students with high levels of connectedness to the university have been found to be more likely to complete their college degree than are students with low levels of university connectedness. This study examined the role of parental and peer attachment as distal predictors of school connectedness. As predicted, it was found that attachment style to…

  11. An Attachment Perspective on Anger among Adolescents

    Science.gov (United States)

    Konishi, Chiaki; Hymel, Shelley

    2014-01-01

    Extending John Bowlby's hypothesis that dysfunctional anger is a predictable outcome of insecure attachments to parents, this study investigated the relationship between current parent-adolescent attachment and both the experience and expression of anger. Participants included 776 students (379 boys and 397 girls) in grades 8-12. As predicted…

  12. Attachment, emotion regulation and adult crying

    NARCIS (Netherlands)

    Maas, J.; Laan, A.; Vingerhoets, A.J.J.M.

    2011-01-01

    Attachment serves to facilitate the contact with and proximity to the primary caregiver, in that way contributing to a safe exploration of the environment. However, due to inconsistencies in the reaction of the caregiver or her/his absence, insecure attachment styles may develop. This chapter summar

  13. Attachment of Salmonella spp. to pork meat

    DEFF Research Database (Denmark)

    Hansen, Trine; Riber, Leise; Löfström, Charlotta;

    2011-01-01

    Five strains of Salmonella, one wildtype and four knock-out mutants (the prg, flhDC, yhjH and fliC genes) were investigated based on their probability to attach and subsequently detach from a surface of pork fillet. The attachment followed by detachment was measured and modelled for two different...

  14. Attachment and Socioemotional Problems in Middle Childhood

    Science.gov (United States)

    Moss, Ellen; Lecompte, Vanessa

    2015-01-01

    In this article, we will evaluate the evidence concerning links between attachment and behavior problems in the middle childhood period. We will first provide a general introduction to the question of attachment and maladaptation in the middle childhood period, and then examine the recent empirical evidence with respect to both externalizing and…

  15. Romantic adult attachment and basic personality structure

    Directory of Open Access Journals (Sweden)

    Jelena Zeleskov Djoric

    2012-03-01

    Full Text Available The main goal of this study was localization of attachment dimensions in the space described by basic personality traits. Study purported to examine relations between attachment and basic personality structure, in a sample of 203 respondents. Romantic adult attachment was measured by the Experience in Close Relationship Scale, basic personality structure was assessed by the NEO-PI-R personality inventory, and Disintegration, which represents operationalization of Schizotypy as a basic personality trait, was estimated by the Delta 10 test. The results of Principal component analysis showed that attachment dimensions are not separate constructs in relation to basic personality traits. Furthermore, results indicate that attachment dimensions represent emotional dysregulation in close interpersonal relationships, because positive correlations are found between dimensions of Attachment and Mania (.35, Anxiety (.51 and Depression (.55. Negative correlations have been obtained between Attachment and Positive emotions (-.34 and Feelings (-.31. These results suggest that Attachment dimensions should be considered as an expression of basic personality traits in romantic adult's relationships.

  16. Attachment and Dependency in Developmental Perspective.

    Science.gov (United States)

    Sroufe, L. Alan; And Others

    1983-01-01

    Distinguishes between attachment (the relationship between infant and caregiver) and dependency (the reliance of the child on adults for nurturance, attention, or assistance). Assesses preschool children with varying attachment histories and suggests that the roots of overdependency lie in the quality of the early infant-caregiver relationship.…

  17. Attachment Theory Applied to Juvenile Sex Offending.

    Science.gov (United States)

    Goodrow, Kenneth K.; Lim, Mee-Gaik

    1998-01-01

    Attachment theory is applied to identify systemic patterns encouraging juveniles to commit sexual offenses. The role of the helping system in perpetuating offenses is reviewed. The priority of family integrity and the role of professionals in breaking cycles of abuse and repairing earlier destructive emotional attachments are discussed. (EMK)

  18. Attachment Parenting: A Style That Works.

    Science.gov (United States)

    Sears, William

    1995-01-01

    Discusses the benefits of attachment parenting, which emphasizes parental commitment, a low-stress pregnancy, childbirth preparation, breast-feeding with child-led weaning, prompt response to the baby's crying, flexible sleeping arrangements, close-knit father-mother-baby functioning, and the avoidance of detachment parenting. Attachment parenting…

  19. Anxiety, cortisol, and attachment predict plasma oxytocin

    NARCIS (Netherlands)

    Tops, Mattie; Van Peer, Jacobien M.; Korf, Jakob; Wijers, Albertus A.; Tucker, Don M.

    2007-01-01

    Oxytocin and attachment seem to interact in suppressing subjective anxiety and physiological stress responses. In this study we investigated the relationships between individual differences in trait attachment scores, state and trait anxiety, plasma cortisol, and plasma oxytocin levels in healthy pr

  20. Forgiveness and health: The role of attachment

    NARCIS (Netherlands)

    Lawler-Row, K.A.; Hyatt-Edwards, L.; Wünsch, K.L.; Karremans, J.C.T.M.

    2011-01-01

    Attachment was examined for its association to forgiveness and health. Young adults were interviewed about a time of conflict with a parent; during rest and interview periods, readings of blood pressure and heart rate were taken. Participants completed surveys of forgiveness, attachment, relationshi

  1. Adolescent Self-Esteem, Attachment and Loneliness

    Science.gov (United States)

    Dhal, Anubha; Bhatia, Sangeeta; Sharma, Vidhi; Gupta, Priyanka

    2007-01-01

    Objectives: To assess self-esteem, loneliness and attachment styles among adolescents and examine their association with each other and with age and gender. Method: Adolescents (55 males and 55 females) from a public school in Delhi, aged 10-13 years were administered Coopersmith Self-Esteem Inventory (School Form), Attachment Scale and UCLA…

  2. Genetic and Environmental Influences on Adolescent Attachment

    Science.gov (United States)

    Fearon, Pasco; Shmueli-Goetz, Yael; Viding, Essi; Fonagy, Peter; Plomin, Robert

    2014-01-01

    Background: Twin studies consistently point to limited genetic influence on attachment security in the infancy period, but no study has examined whether this remains the case in later development. This study presents the findings from a twin study examining the relative importance of genetic and environmental influences on attachment in…

  3. Adult Attachment, Culturally Adjusted Attachment, and Interpersonal Difficulties of Taiwanese Adults

    Science.gov (United States)

    Wang, Chia-Chih DC; Scalise, Dominick A.

    2010-01-01

    This study examines the applicability of Western adult attachment perspectives to interpersonal difficulties experienced by individuals with indigenous Chinese cultural backgrounds. A total of 275 Taiwanese university students completed self-report surveys of adult attachment, ideal attachment, and interpersonal problems. Culturally adjusted…

  4. Attachment and children's biased attentional processing: evidence for the exclusion of attachment-related information.

    Directory of Open Access Journals (Sweden)

    Eva Vandevivere

    Full Text Available Research in both infants and adults demonstrated that attachment expectations are associated with the attentional processing of attachment-related information. However, this research suffered from methodological issues and has not been validated across ages. Employing a more ecologically valid paradigm to measure attentional processes by virtue of eye tracking, the current study tested the defensive exclusion hypothesis in late childhood. According to this hypothesis, insecurely attached children are assumed to defensively exclude attachment-related information. We hypothesized that securely attached children process attachment- related neutral and emotional information in a more open manner compared to insecurely attached children. Sixty-two children (59.7% girls, 8-12 years completed two different tasks, while eye movements were recorded: task one presented an array of neutral faces including mother and unfamiliar women and task two presented the same with happy and angry faces. Results indicated that more securely attached children looked longer at mother's face regardless of the emotional expression. Also, they tend to have more maintained attention to mother's neutral face. Furthermore, more attachment avoidance was related to a reduced total viewing time of mother's neutral, happy, and angry face. Attachment anxiety was not consistently related to the processing of mother's face. Findings support the theoretical assumption that securely attached children have an open manner of processing all attachment-related information.

  5. The Antimicrobial Activity of Porphyrin Attached Polymers

    Science.gov (United States)

    Thompson, Lesley

    2008-03-01

    We are interested in testing the antimicrobial activity of a porphyrin that is attached to a polymer. The porphyrin (5-(4-carboxyphenyl)-10,15,20-tris-(4-pryridyl)) was synthesized from methyl 4-formyl benzoate, 4-pyridinecarboxaldehyde, and pyrrole and attached to a copolymer of polystyrene/poly(vinyl benzyl chloride), which was synthesized by free radical polymerization. The antimicrobial activity of the polymer-attached porphyrin was then determined for gram-negative E. Coli grown to 0.80 OD. In this procedure, glass slides were coated with polymer-attached porphyrin via dip-coating, and the E. Coli bacteria were plated in Luria Broth media. The plates were subsequently exposed to light overnight before they were incubated as porphyrins act as photo-sensitizers when irradiated with light. The polymer-attached porphyrin did exhibit antimicrobial activity and parameters that affect its efficiency will be discussed.

  6. Job Cognition and Justice Influencing Organizational Attachment

    Directory of Open Access Journals (Sweden)

    Sangeeta Sahu

    2014-02-01

    Full Text Available Organizational attachment echoes the psychological bond between employee and employer relations, differing from affective component of commitment in terms of employees’ psychological and behavioral involvement. This study examines the extent to which employee perception about procedural, distributive justice and job cognition contributes toward organizational attachment in India. The effect of justice and job cognition variables relates differently to previous studies from western part of the globe. First, in past studies, procedural justice predicted commitment, whereas, for Indian employees, distributive justice contributed to organizational attachment. Second, the contribution of extrinsic job cognition in organizational attachment was evident in the model developed using Structural Equation Modeling (SEM; AMOS. Organizations must take cognizance of the outcomes exhibited by the behavior of managers while following the laid down policies and processes. Cognition of fairness at workplace and attachment can play key role in limiting retention. Practical implications and future research directions are discussed.

  7. Attachment to groups: theory and measurement.

    Science.gov (United States)

    Smith, E R; Murphy, J; Coats, S

    1999-07-01

    Aspects of people's identification with groups may be understood by borrowing theoretical ideas and measurement strategies from research on attachment in close relationships. People have mental models of the self as a group member and of groups as sources of identity and esteem. These models affect thoughts, emotions, and behaviors related to group membership. Three studies show that two dimensions of attachment to groups, attachment anxiety and avoidance, can be assessed with good reliability, validity, and over-time stability. These factors are distinct from relationship attachment and from other measures of group identification. Group attachment predicts several important outcomes, including emotions concerning the group, time and activities shared with a group, social support, collective self-esteem, and ways of resolving conflict. This conceptualization provides new insights into the nature of people's psychological ties to groups.

  8. Security of attachment and preschool friendships.

    Science.gov (United States)

    Park, K A; Waters, E

    1989-10-01

    Attachment theory proposes that the quality of the mother-child tie predicts the quality of a child's other close relationships. The purpose of this study was to test whether security of attachment to mother is related to the quality of a preschooler's best friendships. 33 4-year-old and their best friends participated (mean age = 46 months). Attachment Q-set data were collected to score security of mother-child attachment. Security data were used to classify the friend pairs as secure-secure or secure-insecure. Best friend dyads were observed for a 1-hour free-play session. Each pair's behavior was described with the Dyadic Relationships Q-set, a measure designed to describe the behavior of a pair of children. Secure-secure pairs were more harmonious, less controlling, more responsive, and happier than secure-insecure pairs. The results are related to previous work on attachment and social competence.

  9. Experimental validation of finite element and boundary element methods for predicting structural vibration and radiated noise

    Science.gov (United States)

    Seybert, A. F.; Wu, T. W.; Wu, X. F.

    1994-01-01

    This research report is presented in three parts. In the first part, acoustical analyses were performed on modes of vibration of the housing of a transmission of a gear test rig developed by NASA. The modes of vibration of the transmission housing were measured using experimental modal analysis. The boundary element method (BEM) was used to calculate the sound pressure and sound intensity on the surface of the housing and the radiation efficiency of each mode. The radiation efficiency of each of the transmission housing modes was then compared to theoretical results for a finite baffled plate. In the second part, analytical and experimental validation of methods to predict structural vibration and radiated noise are presented. A rectangular box excited by a mechanical shaker was used as a vibrating structure. Combined finite element method (FEM) and boundary element method (BEM) models of the apparatus were used to predict the noise level radiated from the box. The FEM was used to predict the vibration, while the BEM was used to predict the sound intensity and total radiated sound power using surface vibration as the input data. Vibration predicted by the FEM model was validated by experimental modal analysis; noise predicted by the BEM was validated by measurements of sound intensity. Three types of results are presented for the total radiated sound power: sound power predicted by the BEM model using vibration data measured on the surface of the box; sound power predicted by the FEM/BEM model; and sound power measured by an acoustic intensity scan. In the third part, the structure used in part two was modified. A rib was attached to the top plate of the structure. The FEM and BEM were then used to predict structural vibration and radiated noise respectively. The predicted vibration and radiated noise were then validated through experimentation.

  10. Exploiting synthetic aperture radar imagery for retrieving vibration signatures of concealed machinery

    Science.gov (United States)

    Pérez, Francisco; Campbell, Justin B.; Jaramillo, Monica; Dunkel, Ralf; Atwood, Thomas; Doerry, Armin; Gerstle, Walter H.; Santhanam, Balu; Hayat, Majeed M.

    2016-05-01

    It has been demonstrated that the instantaneous acceleration associated with vibrating objects that are directly imaged by synthetic aperture radar (SAR) can be estimated through the application of the discrete fractional Fourier transform (DFrFT) using the information contained in the complex SAR image. In general, vibration signatures may include, for example, the number of chirped sinusoids as well as their respective base frequencies and chirp rates. By further processing the DFrFT-processed data for clutter-noise rejection by means of pseudo- subspace methods, has been shown that the SAR-vibrometry method can be reliable as long as the signal-to-noise ratio (SNR) and the signal-to-clutter ratio (SCR) of the slow-time SAR signal at the range-line of interest exceeds 15dB. Meanwhile, the Nyquist theorem dictates that the maximum measurable vibration frequency is limited by half of the pulse-repetition frequency. This paper focuses on the detection and estimation of vibrations generated by machinery concealed within buildings and other structures. This is a challenging task in general because the vibration signatures of the source are typically altered by their housing structure; moreover, the SNR at the surface of the housing structure tends to be reduced. Here, experimental results for three different vibrating targets, including one concealed target, are reported using complex SAR images acquired by the General Atomics Lynx radar at resolutions of 1-ft and 4-in. The concealed vibrating target is actuated by a gear motor with an off-balance weight attached to it, which is enclosed by a wooden housing. The vibrations of the motor are transmitted to a chimney that extends above the housing structure. Using the SAR vibrometry approach, it is shown that it is possible to distinguish among the three vibrating objects based upon their vibration signatures.

  11. Vibration Mitigation without Dissipative Devices: First Large-Scale Testing of a State Switched Inducer

    Directory of Open Access Journals (Sweden)

    Daniel Tirelli

    2014-01-01

    Full Text Available A new passive device for mitigating cable vibrations is proposed and its efficiency is assessed on 45-meter long taut cables through a series of free and forced vibration tests. It consists of a unilateral spring attached perpendicularly to the cable near the anchorage. Because of its ability to change the cable dynamic behaviour through intermittent activation, the device has been called state switched inducer (SSI. The cable behaviour is shown to be deeply modified by the SSI: the forced vibration response is anharmonicc and substantially reduced in amplitude whereas the free vibration decay is largely sped up through a beating phenomenon. The vibration mitigation effect is mainly due to the activation and coupling of various vibration modes, as evidenced in the response spectra of the equipped cable. This first large-scale experimental campaign shows that the SSI outperforms classical passive devices, thus paving the way to a new kind of low-cost vibration mitigation systems which do not rely on dissipation.

  12. Development of the magnetic force-induced dual vibration energy harvester using a unimorph cantilever

    Science.gov (United States)

    Umaba, M.; Nakamachi, E.; Morita, Y.

    2015-12-01

    In this study, a high frequency piezoelectric energy harvester converted from the human low vibrated motion energy was newly developed. This hybrid energy harvester consists of the unimorph piezoelectric cantilever, the pendulum and a pair of permanent magnets. One magnet was attached at the edge of cantilever, and the counterpart magnet at the edge of pendulum. The mechanical energy provided through the human walking motion, which is a typical ubiquitous existence of vibration, is converted to the electric energy via the piezoelectric unimorph cantilever vibration. At first, we studied the energy convert mechanism and analyze the performance of novel energy harvester, where the resonance free vibration of unimorph piezoelectric cantilever generated a high electric power. Next, we equipped the counterpart permanent magnet at the edge of pendulum, which vibrates with a very low frequency caused by the human walking. Then the counterpart magnet was set at the edge of unimorph piezoelectric cantilever, which vibrated with a high frequency. This low-to-high frequency convert "dual vibration system" can be characterized as an enhanced energy harvester. We examined and obtained average values of voltage and power in this system, as 8.31 mV and 0.33 μW. Those results show the possibility to apply for the energy harvester in the portable and implantable Bio-MEMS devices.

  13. Structure and behaviour of proteins, nucleic acids and viruses from vibrational Raman optical activity

    DEFF Research Database (Denmark)

    Barron, L.D.; Blanch, E.W.; McColl, I.H.;

    2003-01-01

    On account of its sensitivity to chirality Raman optical activity (ROA), which may be measured as a small difference in vibrational Raman scattering from chiral molecules in right- and left-circularly polarized incident light, is a powerful probe of structure and behaviour of biomolecules in aque...

  14. Vibrational study of isolated 18-crown-6 ether complexes with alkaline-earth metal cations

    NARCIS (Netherlands)

    Gamez, F.; Hurtado, P.; Martinez-Haya, B.; G. Berden,; Oomens, J.

    2011-01-01

    Laser infrared multiple photon dissociation (IRMPD) spectroscopy has been employed to probe the C-O and C-C stretching vibrational modes of 18-crown-6 ether (18c6) complexes with alkaline-earth metals (Mg(2+), Ca(2+). Sr(2+) and Ba(2+)) stored in the cell of a Fourier Transform Ion Cyclotron Resonan

  15. Vibrational study of isolated 18-crown-6 ether complexes with alkaline-earth metal cations

    NARCIS (Netherlands)

    F. Gámez; P. Hurtado; B. Martínez-Haya; G. Berden; J. Oomens

    2011-01-01

    Laser infrared multiple photon dissociation (IRMPD) spectroscopy has been employed to probe the C-O and C-C stretching vibrational modes of 18-crown-6 ether (18c6) complexes with alkaline-earth metals (Mg2+, Ca2+, Sr2+ and Ba2+) stored in the cell of a Fourier Transform Ion Cyclotron Resonance mass

  16. Nonlinear vibration energy harvesting based on variable double well potential function

    Science.gov (United States)

    Yang, Wei; Towfighian, Shahrzad

    2016-04-01

    Converting ambient mechanical energy to electricity, vibration energy harvesting, enables powering of the low-power remote sensors. Nonlinear energy harvesters have the advantage of a wider frequency spectrum compared to linear resonators making them more efficient in scavenging the broadband frequency of ambient vibrations. To increase the output power of the nonlinear resonators, we propose an energy harvester composed of a cantilever piezoelectric beam carrying a movable magnet facing a fixed magnet at a distance. The movable magnet on the beam is attached to a spring at the base of the beam. The spring-magnet system on the cantilever beam creates the variable double well potential function. The spring attached to the magnet is in its compressed position when the beam is not deflected, as the beam oscillates, the spring energy gradually releases and further increases the amplitude of vibration. To describe the motion of the cantilever beam, we obtained two coupled partial differential equations by assuming the cantilever beam as Euler-Bernoulli beam considering the effect of the moving magnet. Method of multiple scales is used to solve the coupled equations. The cantilever beam with the two magnets is a bi-stable system. Making one magnet movable can create internal resonance that is explored as a mechanism to increase the frequency bandwidth. The effect of system parameters on the frequency bandwidth of the resonator is investigated through numerical solutions. This study benefits vibration energy harvesting to achieve a higher performance when excited by the wideband ambient vibrations.

  17. Longitudinal association between adolescent attachment, adult romantic attachment, and emotion regulation strategies.

    Science.gov (United States)

    Pascuzzo, Katherine; Cyr, Chantal; Moss, Ellen

    2013-01-01

    Attachment security towards parents and peers in adolescence, and romantic attachment styles and emotion regulation strategies in young adulthood, were evaluated using an eight-year longitudinal design. Fifty-six young adults completed the Inventory of Parent and Peer Attachment (IPPA) at age 14, and then, at age 22, the Experience in Close Relationships (ECR) and the Coping Inventory for Stressful Situations (CISS), an emotion regulation questionnaire concerning coping strategies, including task-oriented versus emotion-oriented foci. Results indicated that greater insecurity to parents and peers in adolescence predicted a more anxious romantic attachment style and greater use of emotion-oriented strategies in adulthood. Concurrently, anxious adult attachment style was related to more emotion-oriented strategies, whereas an avoidant attachment style was related to less support-seeking. Analyses also identified emotion-oriented coping strategies as a partial mediator of the link between adolescent attachment insecurity to parents and adult anxious attachment, and a complete mediator of the association between adolescent attachment insecurity to peers and adult anxious attachment. These findings support the core assumption of continuity in attachment theory, where relationships to parents influence close romantic relationships in adulthood.

  18. Slides with no attached paper

    International Nuclear Information System (INIS)

    This document brings together the different presentations (slides) given at the workshop but with no attached paper. These slides refer to the following presentations: - Presentation of ITN (Instituto Tecnologico e Nuclear); - Minor Actinide Partitioning (Dominique Warin); - Transmutation (Janne Wallenius); - Radioactive Waste Management, IGD-TP (Gerald Ouzounian); - Present status of the Swedish nuclear waste management programme (Peter Wikberg); - The U.S. Fuel Cycle Research and Development Program - Separations Research and Development (Terry Todd); - Strategies and national programs of closed fuel cycles - Russian Expert Vision (Mikhael Kormilitsyn) - Extraction Studies Of Potential Solvent Formulations For The GANEX Process (Fiona MacLachlan); - Investigations of The Fundamental Chemistry of the TALSPEAK Process (Ken Nash); - Extraction Separation of Trivalent Minor Actinides and Lanthanides by Hexa-dentate Nitrogen-donor Extractant, TPEN, and its Analogs (Kenji Takeshita); - Fluorinated Diluents for HLW Processing - technological point of view (Vasiliy Babain); - Extraction properties of some new pyridine molecules and search for better diluents (Irena Spendlikova); - Kinetics of extraction of Eu3+ ion by TODGA and CyMe4-BTBP studied using the RMC technique (Trong Hung Vu); - Redox Chemistry of Neptunium in Solutions of Nitric Acid (Alena Paulenova); - NMR applied to actinide ions and their complexes. In search of covalency effects (Geoffrey Vidick); - Towards 'Stability Rules' for Radiolysis of bis-DGA compounds (Ana Nunez); - Pyroprocess Research Activities at IGCAR, Kalpakkam, India (K. Nagarajan); - Critical issues of nuclear energy systems employing molten salt fluorides: from ISTC No. 1606 to No. 3749 (1. year of project activity) and MARS/EVOL cooperation (Victor Ignatiev); - Conversion processes: Internal Gelation and the Sphere-pac concept (Manuel Pouchon); - A Combined Nuclear Technology and Nuclear Chemistry Master. A Unique Initiative

  19. An attachment research perspective on ADHD.

    Science.gov (United States)

    Kissgen, Ruediger; Franke, Sebastian

    2016-06-01

    Since the beginning of clinical attachment research in the mid-1980s the number of research projects in this area has been continuously increasing. The research questions so far can be allocated to numerous medical disciplines such as psychosomatic medicine, adult psychiatry or child and adolescent psychiatry. Recently, children with ADHD and their families have also become subjects of this branch of research. Their specific behavioral characteristics from early childhood on constitute unique challenges on the parent-child interaction. If these interactions develop in a suboptimal way, children may develop an insecure or even a disorganized attachment quality. The latter represents a risk factor for a clinically significant psychopathological development.This article initially presents basic principles of attachment theory and discusses the relevance of the cardinal symptoms of ADHD for clinical attachment research. Subsequently, it outlines and discusses the main results of existing research regarding attachment and ADHD. It concludes with a perspective on research questions that need to be addressed in the future with regard to a transgenerational model that highlights the importance of parental attachment representations to the development of children's attachment quality.

  20. Preschool teacher attachment and attention skills.

    Science.gov (United States)

    Commodari, Elena

    2013-01-01

    Attention underlies and energizes all cognitive and behavioral activities. Many studies showed that the quality of child attachment (both to parental and non parental figures) influences cognitive functions and attention. This study aimed to investigate the relationships among attachment to preschool teachers and attention in a sample of preschoolers. In particular, the study analyzed whether child attachment security to preschool teachers influences the different aspects of their attention skills. In addition, gender- and age-related differences in attention and teacher attachment were explored. Research was conducted using two standardized instruments: the Attention and Concentration Battery, and the Attachment Q Sort. Participants were 279 children (147 male, 132 female) who attended two preschools in a town in Southern Italy. Descriptive analyses, t-tests analyses, and correlation and regression analyses were carried out. Findings highlighted several interesting points concerning the relationships that occur among attachment to preschool teachers and attention. Children with secure attachments presented higher reaction time and better auditory, visual, and visual spatial selectivity and maintenance.

  1. Environmental and genetic influences on early attachment.

    Science.gov (United States)

    Gervai, Judit

    2009-01-01

    Attachment theory predicts and subsequent empirical research has amply demonstrated that individual variations in patterns of early attachment behaviour are primarily influenced by differences in sensitive responsiveness of caregivers. However, meta-analyses have shown that parenting behaviour accounts for about one third of the variance in attachment security or disorganisation. The exclusively environmental explanation has been challenged by results demonstrating some, albeit inconclusive, evidence of the effect of infant temperament. In this paper, after reviewing briefly the well-demonstrated familial and wider environmental influences, the evidence is reviewed for genetic and gene-environment interaction effects on developing early attachment relationships. Studies investigating the interaction of genes of monoamine neurotransmission with parenting environment in the course of early relationship development suggest that children's differential susceptibility to the rearing environment depends partly on genetic differences. In addition to the overview of environmental and genetic contributions to infant attachment, and especially to disorganised attachment relevant to mental health issues, the few existing studies of gene-attachment interaction effects on development of childhood behavioural problems are also reviewed. A short account of the most important methodological problems to be overcome in molecular genetic studies of psychological and psychiatric phenotypes is also given. Finally, animal research focusing on brain-structural aspects related to early care and the new, conceptually important direction of studying environmental programming of early development through epigenetic modification of gene functioning is examined in brief. PMID:19732441

  2. Environmental and genetic influences on early attachment

    Directory of Open Access Journals (Sweden)

    Gervai Judit

    2009-09-01

    Full Text Available Abstract Attachment theory predicts and subsequent empirical research has amply demonstrated that individual variations in patterns of early attachment behaviour are primarily influenced by differences in sensitive responsiveness of caregivers. However, meta-analyses have shown that parenting behaviour accounts for about one third of the variance in attachment security or disorganisation. The exclusively environmental explanation has been challenged by results demonstrating some, albeit inconclusive, evidence of the effect of infant temperament. In this paper, after reviewing briefly the well-demonstrated familial and wider environmental influences, the evidence is reviewed for genetic and gene-environment interaction effects on developing early attachment relationships. Studies investigating the interaction of genes of monoamine neurotransmission with parenting environment in the course of early relationship development suggest that children's differential susceptibility to the rearing environment depends partly on genetic differences. In addition to the overview of environmental and genetic contributions to infant attachment, and especially to disorganised attachment relevant to mental health issues, the few existing studies of gene-attachment interaction effects on development of childhood behavioural problems are also reviewed. A short account of the most important methodological problems to be overcome in molecular genetic studies of psychological and psychiatric phenotypes is also given. Finally, animal research focusing on brain-structural aspects related to early care and the new, conceptually important direction of studying environmental programming of early development through epigenetic modification of gene functioning is examined in brief.

  3. Molecular vibrations the theory of infrared and Raman vibrational spectra

    CERN Document Server

    Wilson, E Bright; Cross, Paul C

    1980-01-01

    Pedagogical classic and essential reference focuses on mathematics of detailed vibrational analyses of polyatomic molecules, advancing from application of wave mechanics to potential functions and methods of solving secular determinant.

  4. Magnetic damping of ski vibrations

    Energy Technology Data Exchange (ETDEWEB)

    Yonnet, J.-P. [CNRS, St. Martin d' Heres (France). Lab. d' Electrotech. de Grenoble; Patton, A.C.; Philippe; Arnould; Bressan, C. [CNRS, St. Martin d' Heres (France). Lab. d' Electrotech. de Grenoble]|[Skis Dynastar S.A., Sallanches (France)

    1998-07-01

    An original damping device has been developed to reduce ski vibrations. Ski movement is transmitted to a conductive sheet situated in a multipole magnetic field created by permanent magnets. The conductive sheet is simultaneously submitted to eddy current and friction forces, giving the damping effect. The eddy current damper is more efficient for high frequency than for low frequency vibrations and consequently is very well adapted to ski vibrations. Bench and snow tests show the positive effects of the damper, which will be commercially available before the end of this year. (orig.)

  5. Active vibration control of a free-free beam by using a tendon mechanism

    Science.gov (United States)

    Tani, Junji; Ueda, Hiroki

    This paper is concerned with an active vibration control of a free-free beam. The beam is reduced to a finite-degree-of-freedom system by the modal analysis, in which the mode function is derived from the transfer matrix method. A control force is produced by a pair of tendons and a DC servo motor attached to the beam. The state of the beam is presumed by the minimum order state observer and the control force is determined by the digital optimum regulator theory. It is found that the active tendon control method is effective to suppress the vibration of the free-free beam.

  6. Modeling and vibration control of an active membrane mirror

    Science.gov (United States)

    Ruggiero, Eric J.; Inman, Daniel J.

    2009-09-01

    The future of space satellite technology lies in ultra-large mirrors and radar apertures for significant improvements in imaging and communication bandwidths. The availability of optical-quality membranes drives a parallel effort for structural models that can capture the dominant dynamics of large, ultra-flexible satellite payloads. Unfortunately, the inherent flexibility of membrane mirrors wreaks havoc with the payload's on-orbit stability and maneuverability. One possible means of controlling these undesirable dynamics is by embedding active piezoelectric ceramics near the boundary of the membrane mirror. In doing so, active feedback control can be used to eliminate detrimental vibration, perform static shape control, and evaluate the health of the structure. The overall motivation of the present work is to design a control system using distributed bimorph actuators to eliminate any detrimental vibration of the membrane mirror. As a basis for this study, a piezoceramic wafer was attached in a bimorph configuration near the boundary of a tensioned rectangular membrane sample. A finite element model of the system was developed to capture the relevant system dynamics from 0 to 300 Hz. The finite element model was compared against experimental results, and fair agreement found. Using the validated finite element models, structural control using linear quadratic regulator control techniques was then used to numerically demonstrate effective vibration control. Typical results show that less than 12 V of actuation voltage is required to eliminate detrimental vibration of the membrane samples in less than 15 ms. The functional gains of the active system are also derived and presented. These spatially descriptive control terms dictate favorable regions within the membrane domain for placing sensors and can be used as a design guideline for structural control applications. The results of the present work demonstrate that thin plate theory is an appropriate modeling

  7. Frequency Identification of Vibration Signals Using Video Camera Image Data

    Directory of Open Access Journals (Sweden)

    Chia-Hung Wu

    2012-10-01

    Full Text Available This study showed that an image data acquisition system connecting a high-speed camera or webcam to a notebook or personal computer (PC can precisely capture most dominant modes of vibration signal, but may involve the non-physical modes induced by the insufficient frame rates. Using a simple model, frequencies of these modes are properly predicted and excluded. Two experimental designs, which involve using an LED light source and a vibration exciter, are proposed to demonstrate the performance. First, the original gray-level resolution of a video camera from, for instance, 0 to 256 levels, was enhanced by summing gray-level data of all pixels in a small region around the point of interest. The image signal was further enhanced by attaching a white paper sheet marked with a black line on the surface of the vibration system in operation to increase the gray-level resolution. Experimental results showed that the Prosilica CV640C CMOS high-speed camera has the critical frequency of inducing the false mode at 60 Hz, whereas that of the webcam is 7.8 Hz. Several factors were proven to have the effect of partially suppressing the non-physical modes, but they cannot eliminate them completely. Two examples, the prominent vibration modes of which are less than the associated critical frequencies, are examined to demonstrate the performances of the proposed systems. In general, the experimental data show that the non-contact type image data acquisition systems are potential tools for collecting the low-frequency vibration signal of a system.

  8. The fourth pattern of attachment: Disorganized / disoriented

    Directory of Open Access Journals (Sweden)

    Zlatka Cugmas

    2003-09-01

    Full Text Available On the basis of the study of recent scientific literature about the development of attachment behavior, the author answers the following questions about: the behavior children categorized as Disorganized/disorientated or Controlling in the procedure of the Strange situation; the life circumstances, in which these children live; the reasons for lack of balanced strategies of attachment and characteristics of their general manner of adaptation. The author finds the characteristics of the mothers' (insensitivity to be significantly influential for the emergence of the fourth pattern of attachment. These children are heterogeneous regarding adaptation in general. Professional help preceding negative consequences for their socioemotional development is neccesary.

  9. Development of a Vibration Powered Micro Generator and its Application to Harvest the Vibration Energy of the KRI KKP-811’s Engine

    Directory of Open Access Journals (Sweden)

    Harus L.G.

    2010-01-01

    Full Text Available Vibration energy harvesting has been receiving a considerable amount of interest as a means of powering wireless sensors and low-power devices. In this paper, an energy harvester is presented to convert ambient mechanical vibration into electrical energy employing magnetoelectric generator. The harvester uses single magnet-spring attached on the coil. When the harvester is excited, the magnet moves relative to the coil, undergoes magnetic field variations and produces a power output. To obtain a maximum power output, the mass of magnet is varied. The magnetoelectric generator with various masses of magnets was tested by a harmonic exciter with various frequencies and amplitudes. The one with maximum power output was then applied to harvest the ambient vibration energy of KRI KKP-811’s Engine. The results show that this prototype can harvest maximum energy of 2μW when it is placed at the base/foundation of the engine.

  10. Vibration transmissibility characteristics of smart spring vibration isolation system

    Institute of Scientific and Technical Information of China (English)

    倪德; 朱如鹏; 陆凤霞; 鲍和云; 付秋菊

    2014-01-01

    The objective of this work was to study the vibration transmissibility characteristics of the undamped and damped smart spring systems. The frequency response characteristics of them were analyzed by using the equivalent linearization technique, and the possible types of the system motion were distinguished by using the starting and ending frequencies. The influences of system parameters on the vibration transmissibility characteristics were discussed. The following conclusions may be drawn from the analysis results. The undamped smart spring system may simultaneously have one starting frequency and one ending frequency or only have one starting frequency, and the damped system may simultaneously have two starting frequencies and one ending frequency. There is an optimal control parameter to make the peak value of the vibration transmissibility curve of the system be minimum. When the mass ratio is far away from the stiffness ratio, the vibration transmissibility is small. The effect of the damping ratio on the system vibration transmissibility is significant while the control parameter is less than its optimal value. But the influence of the relative damping ratio on the vibration transmissibility is small.

  11. 30 CFR 77.1436 - Drum end attachment.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Drum end attachment. 77.1436 Section 77.1436... Hoisting Wire Ropes § 77.1436 Drum end attachment. (a) For drum end attachment, wire rope shall be attached... anchor bolts, clamps, or wedges, provided that the attachment is a design feature of the hoist...

  12. Give Them Roots, Then Let Them Fly: Understanding Attachment Therapy.

    Science.gov (United States)

    McKelvey, Carole A., Ed.

    This book describes attachment theory, presents the attachment therapy program in place at the Evergreen Attachment Center at Evergreen, Colorado, and examines the implications of attachment therapy. The chapters are: (1) "An Overview" (Carole A. McKelvey, John Alston); (2) "Attachment Theory and Assessment" (Michael Orlans, Terry Levy); (3)…

  13. Carbon nanotubes as in vivo bacterial probes

    Science.gov (United States)

    Bardhan, Neelkanth M.; Ghosh, Debadyuti; Belcher, Angela M.

    2014-09-01

    With the rise in antibiotic-resistant infections, non-invasive sensing of infectious diseases is increasingly important. Optical imaging, although safer and simpler, is less developed than other modalities such as radioimaging, due to low availability of target-specific molecular probes. Here we report carbon nanotubes (SWNTs) as bacterial probes for fluorescence imaging of pathogenic infections. We demonstrate that SWNTs functionalized using M13 bacteriophage (M13-SWNT) can distinguish between F‧-positive and F‧-negative bacterial strains. Moreover, through one-step modification, we attach an anti-bacterial antibody on M13-SWNT, making it easily tunable for sensing specific F‧-negative bacteria. We illustrate detection of Staphylococcus aureus intramuscular infections, with ~3.4 × enhancement in fluorescence intensity over background. SWNT imaging presents lower signal spread ~0.08 × and higher signal amplification ~1.4 × , compared with conventional dyes. We show the probe offers greater ~5.7 × enhancement in imaging of S. aureus infective endocarditis. These biologically functionalized, aqueous-dispersed, actively targeted, modularly tunable SWNT probes offer new avenues for exploration of deeply buried infections.

  14. Analysis of a piezoelectric bimorph plate with a central-attached mass as an energy harvester.

    Science.gov (United States)

    Jiang, Shunong; Hu, Yuantai

    2007-07-01

    This article analyzes the performance of a piezoelectric energy harvester in the flexural mode for scavenging ambient vibration energy. The energy harvester consists of a piezoelectric bimorph plate with a central-attached mass. The linear piezoelectricity theory is applied to evaluate the performance dependence upon the physical and geometrical parameters of the model bimorph plate. The analytical solution for the flexural motion of the piezoelectric bimorph plate energy harvester shows that the output power density increases initially, reaches a maximum, then decreases monotonically with the increasing load impedance, which is normalized by a parameter that is a simple combination of the physical and geometrical parameters of the scavenging structure, the bimorph plate, and the frequency of the ambient vibration, underscoring the importance for the load circuit to have the impedance desirable by the scavenging structure. The numerical results illustrate the considerably enhanced performances by adjusting the physical and geometrical parameters of the scavenging structure. PMID:17718336

  15. Vibration insensitive optical ring cavity

    Institute of Scientific and Technical Information of China (English)

    Miao Jin; Jiang Yan-Yi; Fang Su; Bi Zhi-Yi; Ma Long-Sheng

    2009-01-01

    The mounting configuration of an optical ring cavity is optimized for vibration insensitivity by finite element analysis. A minimum response to vertical accelerations is found by simulations made for different supporting positions.

  16. A distributed optical fiber sensing system for synchronous vibration and loss measurement

    Science.gov (United States)

    Zhang, Xu-ping; Qiao, Wei-yan; Sun, Zhen-hong; Shan, Yuan-yuan; Zeng, Jie; Zhang, Yi-xin

    2016-09-01

    We propose a fully distributed fusion system combining phase-sensitive optical time-domain reflectometry (Φ-OTDR) and OTDR for synchronous vibration and loss measurement by setting an ingenious frequency sweep rate ( FSR) of the optical source. The relationships between FSR, probe pulse width and repeat period are given to balance the amplitude fluctuation of OTDR traces, the dead zone probability and the measurable frequency range of vibration events. In the experiment, we achieve synchronous vibration and loss measurement with FSR of 40 MHz/s, the proble pulse width of 100 ns and repeat rate of 0.4 ms. The fluctuation of OTDR trace is less than 0.45 dB when the signal-to-noise ratio ( SNR) is over 12 dB for a captured vibration event located at 9.1 km. The proposed method can be used for not only detection but also early warning of damage events in optical communication networks.

  17. Spectroscopic investigation of the vibrational quasi-continuum arising from internal rotation of a methyl group

    Energy Technology Data Exchange (ETDEWEB)

    Hougen, J.T. [NIST, Gaithersburg, MD (United States)

    1993-12-01

    The goal of this project is to use spectroscopic techniques to investigate in detail phenomena involving the vibrational quasi-continuum in a simple physical system. Acetaldehyde was chosen for the study because: (i) methyl groups have been suggested to be important promotors of intramolecular vibrational relaxation, (ii) the internal rotation of a methyl group is an easily describle large-amplitude motion, which should retain its simple character even at high levels of excitation, and (iii) the aldehyde carbonyl group offers the possibility of both vibrational and electronic probing. The present investigation of the ground electronic state has three parts: (1) understanding the {open_quotes}isolated{close_quotes} internal-rotation motion below, at, and above the top of the torsional barrier, (2) understanding in detail traditional (bond stretching and bending) vibrational fundamental and overtone states, and (3) understanding interactions involving states with multiquantum excitations of at least one of these two kinds of motion.

  18. Vibrational spectra and normal coordinate analysis of p-cresol and its deuterated analogs

    Science.gov (United States)

    Takeuchi, Hideo; Watanabe, Noriko; Harada, Issei

    I.r. and Raman spectra of p-cresol and its seven deuterated analogs were investigated in dilute solutions of hydrophobic solvents. Assignments of the observed i.r. and Raman bands were made on the basis of isotopic frequency shifts, Raman polarization properties, i.r. intensifies and normal coordinate calculations. The calculated normal frequencies are in good agreement with the experimental ones: the average error below 1700 cm -1 is 3.8 cm -1 for 164 in-plane vibrations and 3.3 cm -1 for 59 out-of-plane vibrations. The calculated vibrational modes may be useful in analysing the vibrational spectra of tyrosine. It is suggested that several doublets due to Fermi resonance and a trio of Raman bands in the 1260-1160 cm -1 region are potential probes for the micro-environments of tyrosine side chains in proteins.

  19. Structural, Dynamic, and Vibrational Properties during Heat Transfer in Si/Ge Superlattices: A Car-Parrinello Molecular Dynamics Study

    OpenAIRE

    Ji, Pengfei; Zhang, Yuwen; Yang, Mo

    2016-01-01

    The structural, dynamic, and vibrational properties during the heat transfer process in Si/Ge superlattices, are studied by analyzing the trajectories generated by the ab initio Car-Parrinello molecular dynamics simulation. The radial distribution functions and mean square displacements are calculated and further discussions are made to explain and probe the structural changes relating to the heat transfer phenomenon. Furthermore, the vibrational density of states of the two layers (Si/Ge) ar...

  20. Vibrational Spectral Studies of Gemfibrozil

    Science.gov (United States)

    Benitta, T. Asenath; Balendiran, G. K.; James, C.

    2008-11-01

    The Fourier Transform Raman and infrared spectra of the crystallized drug molecule 5-(2,5-Dimethylphenoxy)-2,2-dimethylpentanoic acid (Gemfibrozil) have been recorded and analyzed. Quantum chemical computational methods have been employed using Gaussian 03 software package based on Hartree Fock method for theoretically modeling the grown molecule. The optimized geometry and vibrational frequencies have been predicted. Observed vibrational modes have been assigned with the aid of normal coordinate analysis.

  1. Harmonic vibrations of multispan beams

    DEFF Research Database (Denmark)

    Dyrbye, Claes

    1996-01-01

    Free and forced harmonic vibrations of multispan beams are determined by a method which implies 1 equation regardless of the configuration. The necessary formulas are given in the paper. For beams with simple supports and the same length of all (n) spans, there is a rather big difference between...... the n´th and the (n+1)´th eigenfrequency. The reason for this phenomenon is explained.Keywords: Vibrations, Eigenfrequencies, Beams....

  2. Vibration Theory, Vol. 1B

    DEFF Research Database (Denmark)

    Asmussen, J. C.; Nielsen, Søren R. K.

    The present collection of MATLAB exercises has been published as a supplement to the textbook, Svingningsteori, Bind 1 and the collection of exercises in Vibration theory, Vol. 1A, Solved Problems. Throughout the exercise references are made to these books. The purpose of the MATLAB exercises is ...... is to give a better understanding of the physical problems in linear vibration theory and to surpress the mathematical analysis used to solve the problems. For this purpose the MATLAB environment is excellent....

  3. Cryogenic devices attached to electron accelerators

    International Nuclear Information System (INIS)

    The cryoeenic equipement attached to electron accelerators used at the CEN.G for fundamental research on point defects in solids is presented and some of their essential technical characteristics are briefly described

  4. Attachment and the Roots of Competence.

    Science.gov (United States)

    Sroufe, L. Alan

    1981-01-01

    Describes research with 12- to 18-month-old infants (N=108) determining whether the quality of an infant's attachment to his/her primary caregiver could predict the nature of his/her emerging personality. (CS)

  5. Are anxiously attached women better mindreaders?

    Science.gov (United States)

    Hünefeldt, Thomas; Laghi, Fiorenzo; Ortu, Francesca

    2013-08-01

    This research was aimed at providing first evidence concerning the relationship between adults' self-reported attachment style and their performance on a standard 'theory of mind' task. Based on adult attachment theory, we hypothesized that the two dimensions of self-reported adult attachment, anxiety and avoidance, are differently related to 'theory of mind,' and that this relationship is moderated by variables concerning the 'theory of mind' stimuli. The 'Experiences in Close Relationships' questionnaire and the 'Reading the Mind in the Eyes' test were administered to 132 young women. In line with our expectations, women's attachment-related anxiety was associated with better mind reading concerning stimuli that were emotionally neutral or difficult to recognize.

  6. Broadband pump-probe spectroscopy with sub-10-fs resolution for probing ultrafast internal conversion and coherent phonons in carotenoids

    International Nuclear Information System (INIS)

    We use pump-probe spectroscopy with broadband detection to study electronic energy relaxation and coherent vibrational dynamics in carotenoids. A fast optical multichannel analyzer combined with a non-collinear optical parametric amplifier allows simultaneous acquisition of the differential transmission dynamics on the 500-700 nm wavelength range with sub-10-fs temporal resolution. The broad spectral coverage enables on the one hand a detailed study of the ultrafast bright-to-dark state internal conversion process; on the other hand, the tracking of the motion of the vibrational wavepacket launched on the ground state multidimensional potential energy surface. We present results on all-trans β-carotene and on a long-chain polyene in solution. The developed experimental setup enables the straightforward acquisition and analysis of coherent vibrational dynamics, highlighting time-frequency domain features with extreme resolution

  7. Vibrational Infrared Lifetime of the Anesthetic nitrous oxide gas in solution

    CERN Document Server

    Chieffo, Logan; Shattuck, Jeffrey; Hong, Mi K; Ziegler, Lawrence; Erramilli, Shyamsunder

    2006-01-01

    The lifetime of the asymmetric fundamental stretching 2218 cm$^{-1}$ vibration of the anesthetic gas nitrous oxide (N$_2$O) dissolved in octanol and olive oil is reported. These solvents are model systems commonly used to assess anesthetic potency. Picosecond time-scale molecular dynamics simulations have suggested that protein dynamics or membrane dynamics play a role in the molecular mechanism of anesthetic action. Ultrafast infrared spectroscopy with 100 fs time resolution is an ideal tool to probe dynamics of anesthetic molecules on such timescales. Pump-probe studies at the peak of the vibrational band yield a lifetime of $55 \\pm 1$ ps in olive oil and $52 \\pm 1 ps$ in octanol. The similarity of lifetimes suggests that energy relaxation of the anesthetic is determined primarily by the hydrophobic nature of the environment, consistent with models of anesthetic action. The results show that nitrous oxide is a good model system for probing anesthetic-solvent interactions using nonlinear infrared spectroscop...

  8. Attachment of Gold Nanoparticles to Carbon Nanotubes

    Institute of Scientific and Technical Information of China (English)

    Xi Cheng MA; Ning LUN; Shu Lin WEN

    2005-01-01

    Carbon nanotubes were initially chemically modified with an H2SO4-HNO3 treatment,and subsequently activated with Pd-Sn catalytic nuclei via a one-step activation approach. These activated nanotubes were used as precursors for obtaining gold nanoparticles-attached nanotubes via simple electroless plating. This approach provides an efficient method for attachment of metal nanostructures to carbon nanotubes. Such novel hybrid nanostructures are attractive for many applications.

  9. God as an Attachment Figure : A Case Study of the God Attachment Language and God Concepts of Anxiously Attached Christian Youths in South Africa

    NARCIS (Netherlands)

    Counted, Victor

    2016-01-01

    This study examines the role of the Christian God as an attachment figure, using the attachment language criteria of a strong and enduring affectionate bond. Respondents were 15 anxiously attached Christian youths, purposefully selected for in-depth interviews to explore their God attachment languag

  10. Ratiometric Fluorescent pH Probes Based on Glycopolymers.

    Science.gov (United States)

    Li, Zhiyun; Zhang, Pengshan; Lu, Wei; Peng, Lun; Zhao, Yun; Chen, Gaojian

    2016-09-01

    Effectively detecting pH changes plays a critical role in exploring cellular functions and determining physiological and pathological processes. A novel ratiometric pH probe based on a glycopolymer, armored with properties of serum-stability, tumor-targeting, and pH monitoring, is designed. Random copolymers of 2-(methacrylamido) glucopyranose and fluorescein O-methacrylate are first synthesized by reversible addition fragmentation chain transfer polymerization. Acryloxyethyl thiocarbamoyl rhodamine B is then attached to the polymer chain to prepare ratiometric fluorescent pH probes via a thiol-ene reaction. The synthesized polymeric probes are characterized by NMR, gel permeation chromatography, UV-vis spectroscopy, and transmission electron microscopy, and the fluorescence responses are examined in phosphate buffer at different pHs. The cytotoxicity and confocal imaging experiments of the probes are detected using HeLa cells, demonstrating a low toxicity and superior biocompatibility for detecting pH changes in bioapplications. PMID:27439338

  11. Attachment of Adolescents to Parents: Turkey Profile

    Directory of Open Access Journals (Sweden)

    Turkan Dogan

    2016-12-01

    Full Text Available The present study aims to determine the attachment of adolescents to their parents according to geographical regions in Turkey and gender. The research group consisted of 6061 adolescents. With an age average of 15.53 years. The Inventory of Attachment to Parents and Friends- Brief Form (EABE was used as data acquisition tool. The results of the study indicated significant difference between the scores of students regarding the inventory of attachment to parents according to regions. Evaluating the findings regarding attachment to father and mother together, the findings were similar, and the attachment levels of adolescents in Middle Anatolia, Eastern Anatolia and Black Sea Region were found to be higher than the ones in other regions. This result may be related with socioeconomic, geographical and cultural structures of the regions. Examining the finding according to gender variable, the scores of male students are significantly lower than the scores of female students. As a result according to the data gained from a wide sample group; the main factors for the attachment of adolescents to their parents in Turkey are the geographical regions in Turkey and the gender. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2016; 8(4.000: 406-419

  12. Removable partial overdentures with mechanical (precision) attachments.

    Science.gov (United States)

    Mensor, M C

    1990-10-01

    Mechanical attachments for overdentures have been available in various forms for over a century. The explosive interest in osseointegration and the effort on the part of the profession to avoid the complete denture as a treatment modality has stirred the interest in positive retentive elements for overdentures represented by the mechanical stud and bar attachments. The cited references provide a resource as a trouble-free guide in the selection and use of the various stud and bar attachment systems. The clinical examples show a pattern of application not generally discussed by the manufacturers, illustrating the simplicity of use with the options for all attachments including magnets. The discussion on magnets comes from 9 years of clinical experience. Rare earth magnets provide excellent adjunct retention, and their assembly follows the same protocol and complexity as stud attachment systems. All magnets, at the present state of the art, have a corrosion potential with the exception of the Laser Sealed Units (Golden Dental, Golden, CO). Finally, the mechanics of the attachment overdenture serves as an excellent training field for the osseointegrated prosthesis, be it the classic Brånemark (Nobelpharma USA, Chicago, IL) restorative or the implant overdenture concept. PMID:2227040

  13. Attachment Theory and the Social Work Curriculum

    Directory of Open Access Journals (Sweden)

    Timothy Page

    2007-05-01

    Full Text Available Attachment theory, as developed by Bowlby and Ainsworth, represented a major departure from the current theories of human development of the time, particularly in its rejection of the major tenets of psychoanalytic theory and its integration of core ideas from evolution theory and cybernetics (Ainsworth & Bowlby, 1991. Attachment theory posits that a foundational human instinct, the desire to achieve safety and protection through proximity to a protective figure, is responsible for the formation of a special class of life-long affectional bonds, referred to as “attachments.” Emotional security is derived to a great extent, according to the theory, from experience with caregivers who are consistently responsive to the developing infant’s expression of attachment behavior toward them. Forty years of empirical research has shown that attachment is a universal characteristic that predicts children’s development of cognitive and social competence, emotional regulation, and positive self-image (Weinfield, Sroufe, Egeland, & Carlson, 1999. Social work educators are currently challenged to better integrate the findings of attachment research into their curricula to reflect more the current state of developmental science.

  14. VESPA: The vibrational spectrometer for the European Spallation Source

    Science.gov (United States)

    Fedrigo, Anna; Colognesi, Daniele; Bertelsen, Mads; Hartl, Monika; Lefmann, Kim; Deen, Pascale P.; Strobl, Markus; Grazzi, Francesco; Zoppi, Marco

    2016-06-01

    VESPA, Vibrational Excitation Spectrometer with Pyrolytic-graphite Analysers, aims to probe molecular excitations via inelastic neutron scattering. It is a thermal high resolution inverted geometry time-of-flight instrument designed to maximise the use of the long pulse of the European Spallation Source. The wavelength frame multiplication technique was applied to provide simultaneously a broad dynamic range (about 0-500 meV) while a system of optical blind choppers allows to trade flux for energy resolution. Thanks to its high flux, VESPA will allow the investigation of dynamical and in situ experiments in physical chemistry. Here we describe the design parameters and the corresponding McStas simulations.

  15. Structure, attachment properties, and ecological importance of the attachment system of English ivy (Hedera helix)

    OpenAIRE

    Melzer, Björn; Seidel, Robin; Steinbrecher, Tina; Speck, Thomas

    2011-01-01

    Root climbers such as English ivy (Hedera helix) rely on specialized adventitious roots for attachment, enabling the plants to climb on a wide range of natural and artificial substrates. Despite their importance for the climbing habit, the biomechanical properties of these specialized adventitious roots compared with standard roots and their performance in the attachment to different host species or inert substrates have not been studied. Here organs and tissues involved in the attachment are...

  16. Neurobiology of secure infant attachment and attachment despite adversity: a mouse model

    OpenAIRE

    Roth, T.L.; Raineki, C.; Salstein, L.; Perry, R; Wilson, T. A. Sullivan; Sloan, A.; Lalji, B.; Hammock, E.; Wilson, D. A.; Levitt, P; Okutani, F.; Kaba, H. (Harry); R.M. Sullivan

    2013-01-01

    Attachment to an abusive caregiver has wide phylogenetic representation, suggesting that animal models are useful in understanding the neural basis underlying this phenomenon and subsequent behavioral outcomes. We previously developed a rat model, in which we use classical conditioning to parallel learning processes evoked during secure attachment (odor-stroke, with stroke mimicking tactile stimulation from the caregiver) or attachment despite adversity (odor-shock, with shock mimicking maltr...

  17. Simulating Displacement and Velocity Signals by Piezoelectric Sensor in Vibration Control Applications

    Directory of Open Access Journals (Sweden)

    G. J. Sheu

    2012-01-01

    Full Text Available Intelligent structures with built-in piezoelectric sensor and actuator that can actively change their physical geometry and/or properties have been known preferable in vibration control. However, it is often arguable to determine if measurement of piezoelectric sensor is strain rate, displacement, or velocity signal. This paper presents a neural sensor design to simulate the sensor dynamics. An artificial neural network with error backpropagation algorithm is developed such that the embedded and attached piezoelectric sensor can faithfully measure the displacement and velocity without any signal conditioning circuitry. Experimental verification shows that the neural sensor is effective to vibration suppression of a smart structure by embedded sensor/actuator and a building structure by surface-attached piezoelectric sensor and active mass damper.

  18. Electron impact cross sections of vibrationally and electronically excited molecules

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Jung-Sik, E-mail: jsyoon@nfri.re.kr [Plasma Technology Research Center, National Fusion Research Institute, 814-2, Osikdo-Dong, Gunsan, Jeollabuk-Do, 573-540 (Korea, Republic of); Song, Mi-Young; Kwon, Deuk-Chul; Choi, Heechol [Plasma Technology Research Center, National Fusion Research Institute, 814-2, Osikdo-Dong, Gunsan, Jeollabuk-Do, 573-540 (Korea, Republic of); Kim, Chang-Geun [National Center for Standard Reference Data, Korea Research Institute of Standards and Science, Doryong-Dong, Yuseong-Gu, Daejeon 305-340 (Korea, Republic of); Kumar, Vijay [B-82, Aarohi Twin Bungalows, Near Govt. Tubewell, Bopal, Ahmedabad-380058 (India)

    2014-10-30

    It is well known that the electron impact cross sections for elastic and inelastic processes for the vibrationally and electronically excited molecules are predominantly different than those for molecules in the ground state. Collisions of low energy electrons with excited molecules play an important role in explaining the behavior of gas discharges in laser and plasma physics, in planetary atmospheres, stars, and interstellar medium and in plasmas widely used in the fabrication of microelectronics. This explains as to why there is a need for having validated sets of electron impact cross sections for different processes. This work reviews the subject of electron collisions with vibrationally and electronically excited molecules in a comprehensive way. The survey has been carried out for a few excited molecules such as H{sub 2}, D{sub 2}, T{sub 2}, HD, HT, DT, N{sub 2}, O{sub 2}, and CO{sub 2}. This review includes the discussion on the methods to produce and detect vibrationally and electronically excited molecules. We will take up the cross section data available in the literature for such molecules on electron scattering, dissociation, ionization and attachment processes and will discuss, evaluate and well-validate the same wherever and whenever possible.

  19. Experimental investigation of jet pulse control on flexible vibrating structures

    Science.gov (United States)

    Karaiskos, Grigorios; Papanicolaou, Panos; Zacharopoulos, Dimitrios

    2016-08-01

    The feasibility of applying on-line fluid jet pulses to actively control the vibrations of flexible structures subjected to harmonic and earthquake-like base excitations provided by a shake table is explored. The operating principles and capabilities of the control system applied have been investigated in a simplified small-scale laboratory model that is a mass attached at the top free end of a vertical flexible slender beam with rectangular cross-section, the other end of which is mounted on an electrodynamic shaker. A pair of opposite jets placed on the mass at the top of the cantilever beam applied the appropriate forces by ejecting pressurized air pulses controlled by on/off solenoid electro-valves via in house developed control software, in order to control the vibration caused by harmonic, periodic and random excitations at pre-selected frequency content provided by the shaker. The dynamics of the structure was monitored by accelerometers and the jet impulses by pressure sensors. The experimental results have demonstrated the effectiveness and reliability of Jet Pulse Control Systems (JPCS). It was verified that the measured root mean square (RMS) vibration levels of the controlled structure from harmonic and earthquake base excitations, could be reduced by approximately 50% and 33% respectively.

  20. Laparoscopic four-way ultrasound probe with histologic biopsy facility using a flexible tru-cut needle

    DEFF Research Database (Denmark)

    Durup Scheel-Hincke, J; Mortensen, M B; Pless, T;

    2000-01-01

    Laparoscopic ultrasound (LUS) is widely used in the staging of upper gastrointestinal malignancies. However, accurate N-staging and pathological confirmation of metastases have proved difficult. A new four-way laparoscopic ultrasound probe has been developed. The probe has a biopsy attachment......, the equipment and the technique are described....

  1. Attachment, personality, and psychopathology among adult inpatients: self-reported romantic attachment style versus Adult Attachment Interview states of mind.

    Science.gov (United States)

    Riggs, Shelley A; Paulson, Adrienne; Tunnell, Ellen; Sahl, Gayla; Atkison, Heather; Ross, Colin A

    2007-01-01

    The present study examined self-reported romantic attachment style and Adult Attachment Interview (AAI) states of mind regarding early attachment relationships, personality dimensions, and psychopathology in a psychiatric sample of trauma survivors. Inpatients (N = 80) admitted to a hospital trauma treatment program were administered the Experiences in Close Relationships Scale, AAI, Millon Clinical Multiaxial Inventory-III, Dissociative Experiences Scale, and Dissociative Disorder Interview Schedule. Self-report and AAI attachment classifications were not related, and different results emerged for the two measures. Self-reported romantic attachment style was significantly associated with personality dimensions, with fearful adults showing the most maladaptive personality profiles. Findings suggested that self-report dimensions of self and other independently contribute to different forms of psychological dysfunction. AAI unresolved trauma was uniquely associated with dissociation and posttraumatic stress disorder, whereas unresolved trauma and unresolved loss jointly contributed to schizotypal and borderline personality disorder scores. The differences in findings between the two measures are discussed with a view toward the developmental and clinical implications. PMID:17241494

  2. Synthesis and fluorescence characteristics of ATP-based FRET probes.

    Science.gov (United States)

    Hardt, Norman; Hacker, Stephan M; Marx, Andreas

    2013-12-28

    Adenosine triphosphate (ATP) analogues labelled with two dyes suitable for undergoing Förster Resonance Energy Transfer (FRET) have the potential to be valuable tools to continuously study the enzymatic activity of ATP consuming enzymes. Here, we present a synthesis strategy that allows obtaining these ATP analogues in a straight-forward manner. Earlier studies indicate that modifying ATP at the O2'- and the γ-position is a very promising starting point for the design of these probes. We synthesized probes modified with five different combinations of dyes attached to these positions and investigated their fluorescence characteristics in the non-cleaved state as well as after enzymatic hydrolysis. All presented probes largely change their fluorescence characteristics upon cleavage. They include ratiometric FRET probes as well as dark quenched analogues. For typical in vitro applications a combination of the sulfonated polymethine dyes Sulfo-Cy3 and Sulfo-Cy5 seems to be most promising due to their excellent solubility in aqueous buffer and a large change of fluorescence characteristics upon cleavage. For this combination of dyes we also synthesized analogues modified at the γ- and the C2- or the O3'-position, respectively, as these attachment sites are also well accepted by certain ATP consuming enzymes. These analogues show comparably large changes in fluorescence characteristics. Overall, we present new ATP-based FRET probes that have the potential to enable monitoring the enzymatic activity of ATP consuming enzymes. PMID:24173528

  3. Application of a load-bearing passive and active vibration isolation system in hydraulic drives

    Science.gov (United States)

    Unruh, Oliver; Haase, Thomas; Pohl, Martin

    2016-09-01

    Hydraulic drives are widely used in many engineering applications due to their high power to weight ratio. The high power output of the hydraulic drives produces high static and dynamic reaction forces and moments which must be carried by the mounts and the surrounding structure. A drawback of hydraulic drives based on rotating pistons consists in multi-tonal disturbances which propagate through the mounts and the load bearing structure and produce structure borne sound at the surrounding structures and cavities. One possible approach to overcome this drawback is to use an optimised mounting, which combines vibration isolation in the main disturbance direction with the capability to carry the reaction forces and moments. This paper presents an experimental study, which addresses the vibration isolation performance of an optimised mounting. A dummy hydraulic drive is attached to a generic surrounding structure with optimised mounting and excited by multiple shakers. In order to improve the performance of the passive vibration isolation system, piezoelectric transducers are applied on the mounting and integrated into a feed-forward control loop. It is shown that the optimised mounting of the hydraulic drive decreases the vibration transmission to the surrounding structure by 8 dB. The presented study also reveals that the use of the active control system leads to a further decrease of vibration transmission of up to 14 dB and also allows an improvement of the vibration isolation in an additional degree of freedom and higher harmonic frequencies.

  4. An investigation of vibration-induced protein desorption mechanism using a micromachined membrane and PZT plate.

    Science.gov (United States)

    Yeh, Po Ying; Le, Yevgeniya; Kizhakkedathu, Jayachandran N; Chiao, Mu

    2008-10-01

    A micromachined vibrating membrane is used to remove adsorbed proteins on a surface. A lead zirconate titanate (PZT) composite (3 x 1 x 0.5 mm) is attached to a silicon membrane (2,000 x 500 x 3 microm) and vibrates in a flexural plate wave (FPW) mode with wavelength of 4,000/3 microm at a resonant frequency of 308 kHz. The surface charge on the membrane and fluid shear stress contribute in minimizing the protein adsorption on the SiO(2) surface. In vitro characterization shows that 57 +/- 10% of the adsorbed bovine serum albumin (BSA), 47 +/- 13% of the immunoglobulin G (IgG), and 55.3~59.2 +/- 8% of the proteins from blood plasma are effectively removed from the vibrating surface. A simulation study of the vibration-frequency spectrum and vibrating amplitude distribution matches well with the experimental data. Potentially, a microelectromechanical system (MEMS)-based vibrating membrane could be the tool to minimize biofouling of in vivo MEMS devices. PMID:18427993

  5. Ultrafast time-resolved pump-probe spectroscopy of PYP by a sub-8 fs pulse laser at 400 nm.

    Science.gov (United States)

    Liu, Jun; Yabushita, Atsushi; Taniguchi, Seiji; Chosrowjan, Haik; Imamoto, Yasushi; Sueda, Keiichi; Miyanaga, Noriaki; Kobayashi, Takayoshi

    2013-05-01

    Impulsive excitation of molecular vibration is known to induce wave packets in both the ground state and excited state. Here, the ultrafast dynamics of PYP was studied by pump-probe spectroscopy using a sub-8 fs pulse laser at 400 nm. The broadband spectrum of the UV pulse allowed us to detect the pump-probe signal covering 360-440 nm. The dependence of the vibrational phase of the vibrational mode around 1155 cm(-1) on the probe photon energy was observed for the first time to our knowledge. The vibrational mode coupled to the electronic transition observed in the probe spectral ranges of 2.95-3.05 and 3.15-3.35 eV was attributed to the wave packets in the ground state and the excited state, respectively. The frequencies in the ground state and excited state were determined to be 1155 ± 1 and 1149 ± 1 cm(-1), respectively. The frequency difference is due to change after photoexcitation. This means a reduction of the bond strength associated with π-π* excitation, which is related to the molecular structure change associated with the primary isomerization process in the photocycle in PYP. Real-time vibrational modes at low frequency around 138, 179, 203, 260, and 317 cm(-1) were also observed and compared with the Raman spectrum for the assignment of the vibrational wave packet.

  6. Phase-referenced probe interferometer for biological surface profiling and displacement measurements

    Science.gov (United States)

    Fang-Yen, Christopher; Chu, Mark C.; Seung, H. Sebastian; Dasari, Ramachandra R.; Feld, Michael S.

    2007-12-01

    We present a probe-based, phase-referenced low coherence interferometer in which the reference field is provided by a fiber end reflection. A gradient-index microlens focuses light onto a sample and collects reflected light. We use the probe interferometer to measure surface profiles of the compound eye of a housefly (Musca domestica) and measure nanometer-scale vibrations in a test sample.

  7. Adaptive learning algorithms for vibration energy harvesting

    International Nuclear Information System (INIS)

    By scavenging energy from their local environment, portable electronic devices such as MEMS devices, mobile phones, radios and wireless sensors can achieve greater run times with potentially lower weight. Vibration energy harvesting is one such approach where energy from parasitic vibrations can be converted into electrical energy through the use of piezoelectric and electromagnetic transducers. Parasitic vibrations come from a range of sources such as human movement, wind, seismic forces and traffic. Existing approaches to vibration energy harvesting typically utilize a rectifier circuit, which is tuned to the resonant frequency of the harvesting structure and the dominant frequency of vibration. We have developed a novel approach to vibration energy harvesting, including adaptation to non-periodic vibrations so as to extract the maximum amount of vibration energy available. Experimental results of an experimental apparatus using an off-the-shelf transducer (i.e. speaker coil) show mechanical vibration to electrical energy conversion efficiencies of 27–34%

  8. Vibration Compensation for Scanning Tunneling Microscope

    Institute of Scientific and Technical Information of China (English)

    LI Meng-chao; FU Xing; WEI Xiao-lei; HU Xiao-tang

    2003-01-01

    The influence of vibration is already one of main obstacles for improving the nano measuring accuracy.The techniques of anti-vibration,vibration isolation and vibration compensation become an important branch in nano measuring field.Starting with the research of sensitivity to vibration of scanning tunneling microscope(STM),the theory,techniques and realization methods of nano vibration sensor based on tunnel effect are initially investigated,followed by developing the experimental devices.The experiments of the vibration detection and vibration compensation are carried out.The experimental results show that vibration sensor based on tunnel effect is characterized by high sensitivity,good frequency characteristic and the same vibratory response characteristic consistent with STM.

  9. SIMULATION OF VIBRATION STRESS RELIEF AFTER WELDING BASED ON FEM

    Institute of Scientific and Technical Information of China (English)

    X.C.Zhao; Y.D.Zhang; H.W.Zhang; Q.Wu

    2008-01-01

    A finite element model is developed for the simulation of vibration stress relief (VSR) after welding.For the nonresonant vibration,the reduction in stress strongly depends on the amplitude of vibration.For the resonant vibration,the vibration frequency is the key for stress relief.The vibration frequency should be close to the structure natural frequency for the desired vibration mode.Only small vibration amplitude is required,which will be amplified during vibration.Vibration time does not have a major impact on vibration stress relief.When the amplitude of vibration stress relief is large,the treatment will be more effective.

  10. Vibration modeling of structural fuzzy with continuous boundary.

    Science.gov (United States)

    Friis, Lars; Ohlrich, Mogens

    2008-02-01

    From experiments it is well known that the vibration response of a main structure with many attached substructures often shows more damping than structural losses in the components can account for. In practice, these substructures, which are not attached in an entirely rigid manner, behave like a multitude of different sprung masses each strongly resisting any motion of the main structure (master) at their base antiresonance. The "theory of structural fuzzy" is intended for modeling such high damping. In the present article the theory of fuzzy structures is briefly outlined and a method of modeling fuzzy substructures examined. This is done by new derivations and physical interpretations are provided. Further, the method is extended and simplified by introducing a simple deterministic approach to determine the boundary impedance of the structural fuzzy. By using this new approach, the damping effect of the fuzzy with spatial memory is demonstrated by numerical simulations of a main beam structure with fuzzy attachments. It is shown that the introduction of spatial memory reduces the damping effect of the fuzzy and in certain cases the damping effect may even be eliminated completely. PMID:18247876

  11. Parental incarceration, attachment and child psychopathology.

    Science.gov (United States)

    Murray, Joseph; Murray, Lynne

    2010-07-01

    Theory and evidence relating parental incarceration, attachment, and psychopathology are reviewed. Parental incarceration is a strong risk factor for long-lasting psychopathology, including antisocial and internalizing outcomes. Parental incarceration might threaten children's attachment security because of parent-child separation, confusing communication about parental absence, restricted contact with incarcerated parents, and unstable caregiving arrangements. Parental incarceration can also cause economic strain, reduced supervision, stigma, home and school moves, and other negative life events for children. Thus, there are multiple possible mechanisms whereby parental incarceration might increase risk for child psychopathology. Maternal incarceration tends to cause more disruption for children than paternal incarceration and may lead to greater risk for insecure attachment and psychopathology. Children's prior attachment relations and other life experiences are likely to be of great importance for understanding children's reactions to parental incarceration. Several hypotheses are presented about how prior insecure attachment and social adversity might interact with parental incarceration and contribute to psychopathology. Carefully designed longitudinal studies, randomized controlled trials, and cross-national comparative research are required to test these hypotheses.

  12. Surface-attachment sequence in Vibrio Cholerae

    Science.gov (United States)

    Utada, Andrew; Gibiansky, Maxsim; Wong, Gerard

    2013-03-01

    Vibrio cholerae is a gram-negative bacterium that causes the human disease cholera. It is found natively in brackish costal waters in temperate climates, where it attaches to the surfaces of a variety of different aquatic life. V. cholerae has a single polar flagellum making it highly motile, as well as a number of different pili types, enabling it to attach to both biotic and abiotic surfaces. Using in-house built tracking software we track all surface-attaching bacteria from high-speed movies to examine the early-time attachment profile of v. cholerae onto a smooth glass surface. Similar to previous work, we observe right-handed circular swimming trajectories near surfaces; however, in addition we see a host of distinct motility mechanisms that enable rapid exploration of the surface before forming a more permanent attachment. Using isogenic mutants we show that the motility mechanisms observed are due to a complex combination of hydrodynamics and pili-surface interactions. Lauga, E., DiLuzio, W. R., Whitesides, G. M., Stone, H. A. Biophys. J. 90, 400 (2006).

  13. Design for Vibrator Field Experiment Based- on Vibrator- earth System

    Institute of Scientific and Technical Information of China (English)

    Chen Zubin; Lin Jun; Liang Tiecheng; Zhang Linhang

    2000-01-01

    Source- generated energy in seismic vibrator records high frequency harmonic behavior. Conventional vibratorearth coupling model was set up on the linear system. Some assumptions in the application of linear theory to the vibrator problem play an insignificant role in the overall coupling structure. Obviously, non- linear behaviors can be modeled using a "hard - spring" form of the Duffing equation. Model dedicates that a qualitatively similar harmonic component is present for a broad range of possible mathematical descriptions. After some qualitative analysis about the non- linear system, some conclusion can be drawn. Firstly, The design of the vibrator weight should be abided by two points as followed: In order to avoid decoupling for the vibrator to the earth, the weight should be greater than the peak of the driving force amplitude as to keep the resultant force pointing to the earth's core. On the other hand, for the limited energy output, the vibrator overweight may damage the system high - frequency ability. Secondly, as the driving force frequency approaching to the ground hard- spring inherent frequency, the energy transmission was found to climb its peak from the system energy absorbed curve. At last, due to the non- linear coupling model system, its load curve would come into unstable frequency range,which might limit the application of the Vibroseis conventional sweeping pattern - linear sweep. A new sweeping pattern was listed: the driving signal was the pseudo- random sequence modulated by a fixed frequency cosine signal satisfying with the exploration precision and absorbing efficiency. The synthesized signal was ready to be realized by the electromagnetic driven system. Even the side- lobes noise of its auto- correlation function was restrained well. The theory coming from the Vibrator- earth coupling model was applied to the design of the Portable High- frequency Vibrator System (PHVS), and the good result was obtained. By the analysis of the

  14. Design and synthesis of fluorescent and biotin tagged probes for the study of molecular actions of FAF1 inhibitor.

    Science.gov (United States)

    Yoo, Sung-eun; Yu, Changsun; Jung, SeoHee; Kim, Eunhee; Kang, Nam Sook

    2016-02-15

    To study the molecular action of ischemic Fas-mediated cell death inhibitor, we prepared fluorescent-tagged and biotin-tagged probes of the potent inhibitor, KR-33494, of ischemic cell death. We used the molecular modeling technique to find the proper position for attaching those probes with minimum interference in the binding process of probes with Fas-mediated cell death target, FAF1.

  15. Application of tuned liquid damper in vibration suppression of wind towers

    Energy Technology Data Exchange (ETDEWEB)

    Poshnejad, A. [Ryerson Polytechnic Univ., Toronto, ON (Canada)

    2010-07-01

    The structural responses of a wind turbine were simulated with an attached damping tuned liquid damper (TLD) designed to control vibrations. The proposed TLD was an annular liquid container designed to be installed below the nacelle around the tower body. The TLD-structure system was formulated as a nonlinear coupled response between the TLD hydrodynamic force and the structure response. The effectiveness of the damper was compared with the dampers typically used in antenna designs. A circuit shallow TLD was used as a vibration damper. The sloshing behaviour of water was then modelled using a computational fluid dynamics (CFD) tool and an equivalent mechanical model. Vibration dynamics were considered for the rotor blades; the mechanical-electrical drive train; the yaw system; and the entire wind turbine. Results of the investigation demonstrated that the TLD effectively increased the damping of the wind tower. tabs., figs.

  16. Experimental Comparison of two Active Vibration Control Approaches: Velocity Feedback and Negative Capacitance Shunt Damping

    Science.gov (United States)

    Beck, Benjamin; Schiller, Noah

    2013-01-01

    This paper outlines a direct, experimental comparison between two established active vibration control techniques. Active vibration control methods, many of which rely upon piezoelectric patches as actuators and/or sensors, have been widely studied, showing many advantages over passive techniques. However, few direct comparisons between different active vibration control methods have been made to determine the performance benefit of one method over another. For the comparison here, the first control method, velocity feedback, is implemented using four accelerometers that act as sensors along with an analog control circuit which drives a piezoelectric actuator. The second method, negative capacitance shunt damping, consists of a basic analog circuit which utilizes a single piezoelectric patch as both a sensor and actuator. Both of these control methods are implemented individually using the same piezoelectric actuator attached to a clamped Plexiglas window. To assess the performance of each control method, the spatially averaged velocity of the window is compared to an uncontrolled response.

  17. Simple vibration modeling of structural fuzzy with continuous boundary by including two-dimensional spatial memory

    DEFF Research Database (Denmark)

    Friis, Lars; Ohlrich, Mogens

    2008-01-01

    -dimensional continuous boundary. Additionally, a simple method for determining the so-called equivalent coupling factor is presented. The validity of this method is demonstrated by numerical simulations of the vibration response of a master plate structure with fuzzy attachments. It is revealed that the method performs......Many complicated systems of practical interest consist basically of a well-defined outer shell-like master structure and a complicated internal structure with uncertain dynamic properties. Using the "fuzzy structure theory" for predicting audible frequency vibration, the internal structure......-dimensional continuous boundary was examined in a companion paper (L. Friis and M. Ohlrich, "Vibration modeling of structural fuzzy with continuous boundary," J. Acoust. Soc. Am. 123, 718-728 (2008)). In the present paper, this method is extended, such that it allows modeling of fuzzy substructures with a two...

  18. Extended abstracts: Microbeam Probes of Cellular Radiation Response [final report

    International Nuclear Information System (INIS)

    In July 1999, we organized the 4th International Workshop: Microbeam Probes of Cellular Radiation Response, held in Killiney Bay, Dublin, Ireland, on July 17-18. Roughly 75 scientists (about equal numbers of physicists and biologists) attended the workshop, the fourth in a bi-annual series. Extended abstracts from the meeting were published in the Radiation Research journal, vol. 153, iss. 2, pp. 220-238 (February 2000)(attached). All the objectives in the proposal were met

  19. Vibrations on board and health effects

    DEFF Research Database (Denmark)

    Jensen, Anker; Jepsen, Jørgen Riis

    2014-01-01

    There is only limited knowledge of the exposure to vibrations of ships’ crews and their risk of vibration-induced health effects. Exposure to hand-arm vibrations from the use of vibrating tools at sea does not differ from that in the land-based trades. However, in contrast to most other work places...... of the health consequences of whole body vibrations in land-transportation, such exposure at sea may affect ships’ passengers and crews. While the relation of back disorders to high levels of whole body vibration has been demonstrated among e.g. tractor drivers, there are no reported epidemiological evidence...

  20. Research on cylindrical shell vibration reduction systems

    Institute of Scientific and Technical Information of China (English)

    XING Xiao-liang; WANG Min-qing

    2008-01-01

    Longitudinal and horizontal vibration must both be reduced in an effective vibration isolation system. We present a cylindrical shell vibration isolator as a dynamic system composed of four springs and dampers. Vibration is directly produced by the motion of machinery, and more is subsequently generated by harmonic frequencies within their structure. To test the effectiveness of our isolator, we first determined equations for the transmission of vibration from the machine to its cylindrical shell. Damping effects produced by the vibration parameters of our system are then analyzed.

  1. Parent Attachment, Childrearing Behavior, and Child Attachment: Mediated Effects Predicting Preschoolers' Externalizing Behavior

    Science.gov (United States)

    Roskam, Isabelle; Meunier, Jean-Christophe; Stievenart, Marie

    2011-01-01

    Attachment theory provides an interesting background for thinking about externalizing behavior (EB) in early childhood and for understanding how parenting influences the child's outcomes. The study examined how attachment and parenting could be combined to explain preschoolers' EB. Data were collected from 117 preschoolers aged from 4 to 6…

  2. Measuring Lifestyle and Attachment: An Empirical Investigation Linking Individual Psychology and Attachment Theory

    Science.gov (United States)

    Peluso, Paul R.; Peluso, Jennifer P.; Buckner, Janine P.; Kern, Roy M.; Curlette, William

    2009-01-01

    P. R. Peluso, J. P. Peluso, J. F. White, and R. M. Kern (2004) reviewed the theoretical constructs underlying the similarities between lifestyle and attachment style. Specifically, they suggested that the individual psychology construct of lifestyle (or style of life) and attachment style should be empirically investigated. The present research…

  3. Maternal Attachment Representations, Maternal Sensitivity, and the Infant-Mother Attachment Relationship.

    Science.gov (United States)

    Pederson, David R.; Gleason, Karin E.; Moran, Greg; Bento, Sandi

    1998-01-01

    Examined the mediating role of maternal sensitivity for the association between maternal attachment representations and the quality of infant-mother attachment. Found that autonomous mothers and mothers in secure relationships were more sensitive at home than nonautonomous mothers and mothers in nonsecure relationships, respectively. Infants in…

  4. Analysis of a Lorentz force based vibration exciter using permanent magnets mounted on a piezoelectric stack

    Indian Academy of Sciences (India)

    Arghya Nandi; Sumanta Neogy; Sankha Bhaduri

    2011-02-01

    This work presents performance analysis of a Lorentz force based noncontact vibration exciter by mounting a couple of permanent magnets on a piezoelectric stack. A conductor is attached to the structure to be excited and is placed midway between unlike poles of a couple of permanent magnets. The permanent magnets are placed on a piezoelectric stack. This stack, because of its nano-positioning capabilities, can impart an accurate and adjustable harmonic vibratory motion to the couple of permanent magnets. The piezoelectric stack, because of its high stiffness remains uncoupled with the dynamics of the structure. Due to the relative motion between the magnets and the conductor, Lorentz force is generated within the conductor. This Lorentz force is responsible for vibration of the structure in a plane parallel to the pole faces of the magnets. This keeps the magnetic field almost independent of the vibration of the structure and the chance of the structure hitting the magnet during large vibration is totally eliminated. If the amplitude of displacement of the stack is kept constant, the non-contact excitation force in this exciter remains proportional to the excitation frequency. Though use of this exciter eliminates mass (apart from that of the conductor attached to the structure) and stiffness coupling, a known damping term gets added to that of the excited structure.

  5. Mechanical Vibrations Modeling and Measurement

    CERN Document Server

    Schmitz, Tony L

    2012-01-01

    Mechanical Vibrations:Modeling and Measurement describes essential concepts in vibration analysis of mechanical systems. It incorporates the required mathematics, experimental techniques, fundamentals of modal analysis, and beam theory into a unified framework that is written to be accessible to undergraduate students,researchers, and practicing engineers. To unify the various concepts, a single experimental platform is used throughout the text to provide experimental data and evaluation. Engineering drawings for the platform are included in an appendix. Additionally, MATLAB programming solutions are integrated into the content throughout the text. This book also: Discusses model development using frequency response function measurements Presents a clear connection between continuous beam models and finite degree of freedom models Includes MATLAB code to support numerical examples that are integrated into the text narrative Uses mathematics to support vibrations theory and emphasizes the practical significanc...

  6. Source model for blasting vibration

    Institute of Scientific and Technical Information of China (English)

    DING; Hua(丁桦); ZHENG; Zhemin(郑哲敏)

    2002-01-01

    By analyzing and comparing the experimental data, the point source moment theory and the cavity theory, it is concluded that the vibrating signals away from the blasting explosive come mainly from the natural vibrations of the geological structures near the broken blasting area. The source impulses are not spread mainly by the inelastic properties (such as through media damping, as believed to be the case by many researchers) of the medium in the propagation pass, but by this structure. Then an equivalent source model for the blasting vibrations of a fragmenting blasting is proposed, which shows the important role of the impulse of the source's time function under certain conditions. For the purpose of numerical simulation, the model is realized in FEM, The finite element results are in good agreement with the experimental data.

  7. Vibration analysis of atomising discs

    Energy Technology Data Exchange (ETDEWEB)

    Deng, H; Ouyang, H, E-mail: H.Ouyang@liverpool.ac.u [Department of Engineering, University of Liverpool, Liverpool L69 3GH (United Kingdom)

    2009-08-01

    The centrifugal atomisation of metallic melts using a spinning disc is an important process for powder production and spray deposition. In the manufacturing process the high-temperature melt flows down to the surface of the atomising disc spinning at very high speed. It is observed that there is a hydraulic jump of the melt flow prior to atomisation. In this paper, the dynamic model of the atomising disc as a spinning Kirchhoff plate with this hydraulic jump is established. The flowing melt is modelled as moving mass and weight force in the radial direction. Using a Galerkin method, it is found that the vibration properties of the atomising disc vary with the disc clamping ratio. The amplitude of the vibration is largely raised when the clamping ratio is smaller than the critical jump radius ratio. It is also found that the disc vibration is non-stationary before becoming steady and the amplitude decreases with increasing disc speed.

  8. An Ultrasonographic Periodontal Probe

    Science.gov (United States)

    Bertoncini, C. A.; Hinders, M. K.

    2010-02-01

    Periodontal disease, commonly known as gum disease, affects millions of people. The current method of detecting periodontal pocket depth is painful, invasive, and inaccurate. As an alternative to manual probing, an ultrasonographic periodontal probe is being developed to use ultrasound echo waveforms to measure periodontal pocket depth, which is the main measure of periodontal disease. Wavelet transforms and pattern classification techniques are implemented in artificial intelligence routines that can automatically detect pocket depth. The main pattern classification technique used here, called a binary classification algorithm, compares test objects with only two possible pocket depth measurements at a time and relies on dimensionality reduction for the final determination. This method correctly identifies up to 90% of the ultrasonographic probe measurements within the manual probe's tolerance.

  9. Hard probes 2006 Asilomar

    CERN Multimedia

    2006-01-01

    "The second international conference on hard and electromagnetic probes of high-energy nuclear collisions was held June 9 to 16, 2006 at the Asilomar Conference grounds in Pacific Grove, California" (photo and 1/2 page)

  10. Attachment theory: a biological basis for psychotherapy?

    Science.gov (United States)

    Holmes, J

    1993-10-01

    John Bowlby bemoaned the separation between the biological and psychological approaches in psychiatry, and hoped that attachment theory, which brings together psychoanalysis and the science of ethology, would help bridge the rift between them. Recent findings in developmental psychology have delineated features of parent-infant interaction, especially responsiveness, attunement, and modulation of affect, which lead to either secure or insecure attachment. Similar principles can be applied to the relationship between psychotherapist and patient--the provision of a secure base, the emergence of a shared narrative ('autobiographical competence'), the processing of affect, coping with loss--these are common to most effective psychotherapies and provide the basis for a new interpersonal paradigm within psychotherapy. Attachment theory suggests they rest on a sound ethological and hence biological foundation.

  11. Application of impact dampers in vibration control of flexible structures

    Science.gov (United States)

    Akl, Fred A.; Butt, Aamir S.

    1995-01-01

    Impact dampers belong to the category of passive vibration devices used to attenuate the vibration of discrete and continuous systems. An impact damper generally consists of a mass which is allowed to travel freely between two defined stops. Under the right conditions, the vibration of the structure to which the impact damper is attached will cause the mass of the impact damper to strike the structure. Previous analytical and experimental research work on the effect of impact dampers in attenuating the vibration of discrete and continuous systems have demonstrated their effectiveness. It has been shown in this study that impact dampers can increase the intrinsic damping of a lightly-damped flexible structure. The test structure consists of a slender flexible beam supported by a pin-type support at one end and supported by a linear helical flexible spring at another location. Sinusoidal excitation spanning the first three natural frequencies was applied in the horizontal plane. The orientation of the excitation and the test structure in the horizontal plane minimizes the effect of gravity on the behavior of the test structure. The excitation was applied using a linear sine sweep technique. The span of the test structure, the mass of the impact damper, the distance of travel, and the location of the impact damper along the span of the test structure were varied. The damping ratio are estimated for sixty test configurations. The results show that the impact damper significantly increases the damping ratio of the test structure. Statistical analysis of the results using the method of multiple linear regression indicates that a reasonable fit has been accomplished. It is concluded that additional experimental analysis of flexible structures in microgravity environment is needed in order to achieve a better understanding of the behavior of impact damper under conditions of microgravity. Numerical solution of the behavior of flexible structures equipped with impact

  12. Family systems theory, attachment theory, and culture.

    Science.gov (United States)

    Rothbaum, Fred; Rosen, Karen; Ujiie, Tatsuo; Uchida, Nobuko

    2002-01-01

    Family systems theory and attachment theory have important similarities and complementarities. Here we consider two areas in which the theories converge: (a) in family system theorists' description of an overly close, or "enmeshed," mother-child dyad, which attachment theorists conceptualize as the interaction of children's ambivalent attachment and mothers' preoccupied attachment; (b) in family system theorists' description of the "pursuer-distance cycle" of marital conflict, which attachment theorists conceptualize as the interaction of preoccupied and dismissive partners. We briefly review family systems theory evidence, and more extensively review attachment theory evidence, pertaining to these points of convergence. We also review cross-cultural research, which leads us to conclude that the dynamics described in both theories reflect, in part, Western ways of thinking and Western patterns of relatedness. Evidence from Japan suggests that extremely close ties between mother and child are perceived as adaptive, and are more common, and that children experience less adverse effects from such relationships than do children in the West. Moreover, in Japan there is less emphasis on the importance of the exclusive spousal relationship, and less need for the mother and father to find time alone to rekindle romantic, intimate feelings and to resolve conflicts by openly communicating their differences. Thus, the "maladaptive" pattern frequently cited by Western theorists of an extremely close mother-child relationship, an unromantic, conflictual marriage characterized by little verbal communication and a peripheral, distant father, may function very differently in other cultures. While we believe that both theories will be greatly enriched by their integration, we caution against the application of either theory outside the cultures in which they were developed.

  13. DOWNHOLE VIBRATION MONITORING & CONTROL SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Martin E. Cobern

    2004-08-31

    The deep hard rock drilling environment induces severe vibrations into the drillstring, which can cause reduced rates of penetration (ROP) and premature failure of the equipment. The only current means of controlling vibration under varying conditions is to change either the rotary speed or the weight-on-bit (WOB). These changes often reduce drilling efficiency. Conventional shock subs are useful in some situations, but often exacerbate the problems. The objective of this project is development of a unique system to monitor and control drilling vibrations in a ''smart'' drilling system. This system has two primary elements: (1) The first is an active vibration damper (AVD) to minimize harmful axial, lateral and torsional vibrations. The hardness of this damper will be continuously adjusted using a robust, fast-acting and reliable unique technology. (2) The second is a real-time system to monitor drillstring vibration, and related parameters. This monitor adjusts the damper according to local conditions. In some configurations, it may also send diagnostic information to the surface via real-time telemetry. The AVD is implemented in a configuration using magnetorheological (MR) fluid. By applying a current to the magnetic coils in the damper, the viscosity of the fluid can be changed rapidly, thereby altering the damping coefficient in response to the measured motion of the tool. Phase I of this program entailed modeling and design of the necessary subsystems and design, manufacture and test of a full laboratory prototype. Phase I of the project was completed by the revised end date of May 31, 2004. The objectives of this phase were met, and all prerequisites for Phase II have been completed.

  14. Reduction of Structural Vibrations by Passive and Semiactively Controlled Friction Dampers

    Directory of Open Access Journals (Sweden)

    L. Gaul

    2014-01-01

    Full Text Available Reduction of structural vibrations is of major interest in mechanical engineering for lowering sound emission of vibrating structures, improving accuracy of machines, and increasing structure durability. Besides optimization of the mechanical design or various types of passive damping treatments, active structural vibration control concepts are efficient means to reduce unwanted vibrations. In this contribution, two different semiactive control concepts for vibration reduction are proposed that adapt to the normal force of attached friction dampers. Thereby, semiactive control concepts generally possess the advantage over active control in that the closed loop is intrinsically stable and that less energy is required for the actuation than in active control. In the chosen experimental implementation, a piezoelectric stack actuator is used to apply adjustable normal forces between a structure and an attached friction damper. Simulation and experimental results of a benchmark structure with passive and semiactively controlled friction dampers are compared for stationary narrowband excitation. For simulations of the control performance, transient simulations must be employed to predict the achieved vibration damping. It is well known that transient simulation of systems with friction and normal contact requires excessive computational power due to the nonlinear constitutive laws and the high contact stiffnesses involved. However, commercial finite-element codes do not allow simulating feedback control in a general way. As a remedy, a special simulation framework is developed which allows efficiently modeling interfaces with friction and normal contact by appropriate constitutive laws which are implemented by contact elements in a finite-element model. Furthermore, special model reduction techniques using a substructuring approach are employed for faster simulation.

  15. Sensibility to Changes of Vibrational Modes of Excited Electron: Sum Frequency Signals Versus Difference Frequency Signals*

    Institute of Scientific and Technical Information of China (English)

    GU An-Na; LIANG Xian-Ting

    2011-01-01

    In this paper, we investigate a two electronic level system with vibrational modes coupled to a Brownian oscillator bath. The difference frequency generation (DFG) signals and sum frequency generation (SFG) signals are calculated. It is shown that, for the same model, the SFG signals are more sensitive than the DFG signals to the changes of the vibrational modes of the electronic two-level system. Because the SFG conversion efficiency can be improved by using the time-delay method, the findings in this paper predict that the SFG spectrum may probe the changes of the microstructure more effectively.

  16. Effect of attachment strategies on bipartite networks

    DEFF Research Database (Denmark)

    Ganguly, N.; Saha, S.; Maiti, A.;

    2013-01-01

    rate. Here, we focus on the case where one of the partitions can be assumed to be fixed while the other partition grows in time as observed in the codon-gene or alphabet-word network. We show that subtle changes in growth dynamics, particularly in the attachment kernel, can lead to drastic changes...... of the emergent topological properties. We present a detail analysis of various growth strategies, including sequential and parallel addition of nodes, as well as with and without replacement attachment kernels. Analytical results have been compared with stochastic simulations as well as with real systems showing...

  17. Assortativity in generalized preferential attachment models

    CERN Document Server

    Krot, Alexander

    2016-01-01

    In this paper, we analyze assortativity of preferential attachment models. We deal with a wide class of preferential attachment models (PA-class). It was previously shown that the degree distribution in all models of the PA-class follows a power law. Also, the global and the average local clustering coefficients were analyzed. We expand these results by analyzing the assortativity property of the PA-class of models. Namely, we analyze the behavior of $d_{nn}(d)$ which is the average degree of a neighbor of a vertex of degree $d$.

  18. Innovative Techniques Simplify Vibration Analysis

    Science.gov (United States)

    2010-01-01

    In the early years of development, Marshall Space Flight Center engineers encountered challenges related to components in the space shuttle main engine. To assess the problems, they evaluated the effects of vibration and oscillation. To enhance the method of vibration signal analysis, Marshall awarded Small Business Innovation Research (SBIR) contracts to AI Signal Research, Inc. (ASRI), in Huntsville, Alabama. ASRI developed a software package called PC-SIGNAL that NASA now employs on a daily basis, and in 2009, the PKP-Module won Marshall s Software of the Year award. The technology is also used in many industries: aircraft and helicopter, rocket engine manufacturing, transportation, and nuclear power."

  19. [Raman active vibrations of aluminosilicates].

    Science.gov (United States)

    Pan, Feng; Yu, Xue-hui; Mo, Xuan-xue; You, Jing-lin; Wang, Chen; Chen, Hui; Jiang, Guo-chang

    2006-10-01

    Raman spectra of aluminosilicate minerals, namely kyanite, andalusite, and sillimanite and K2O-Al2O3-SiO2 glasses were recorded. Four alumino-silicon tetrahedral model clusters were calculated by self-consistent (SCF) molecular orbital ab-ini-tio calculation of the quantum chem (QC) method. The result shows a decrease tendency in Raman frequencies in the 800-1200 cm(-1) frequency region with increase in four-coordinated Al content, which is assigned to the Si--Onb symmetry stretching vibrations. The Raman spectra in the 700-800 cm(-1) frequency region is attributed to Al-Onb symmetry stretching vibrations. PMID:17205741

  20. The vibration of rolling discs

    OpenAIRE

    Ferguson, Neil Stuart

    1988-01-01

    The study presented is a fundamental investigation into the vibration of a rolling disc and an analysis of the sound which is then produced by the disc response. In order to characterise the disc's behaviour the free and forced vibration of a thin disc is analysed with the additional conditions which occur in rolling. These conditions include the geometric boundary conditions, the effect of the in-plane load, the change due to rotation of the disc and the effect of contact on the disc which i...

  1. Localized vibrations of graphene nanoribbons

    Science.gov (United States)

    Savin, A. V.; Kivshar, Yu. S.

    2016-08-01

    Vibrational modes of graphene nanoribbons are studied. It is demonstrated that in an unstretched graphene nanoribbon, localized vibrations (in the form of breathers) can occur only at the edges. The largest number of localized edge oscillations is expected for the nanoribbons with the armchair structure. Stretching of a nanoribbon can lead to the appearance of new types of strongly localized oscillations. When a nanoribbon is stretched, in its oscillatory spectrum a frequency gap appears in which the frequencies of the localized modes are located. An armchair nanoribbon can support localized modes only at its edges, while a highly stretched zigzag nanoribbon can support them both at the edges and inside the nanoribbon.

  2. Design and Calibration Tests of an Active Sound Intensity Probe

    Directory of Open Access Journals (Sweden)

    Thomas Kletschkowski

    2008-01-01

    Full Text Available The paper presents an active sound intensity probe that can be used for sound source localization in standing wave fields. The probe consists of a sound hard tube that is terminated by a loudspeaker and an integrated pair of microphones. The microphones are used to decompose the standing wave field inside the tube into its incident and reflected part. The latter is cancelled by an adaptive controller that calculates proper driving signals for the loudspeaker. If the open end of the actively controlled tube is placed close to a vibrating surface, the radiated sound intensity can be determined by measuring the cross spectral density between the two microphones. A one-dimensional free field can be realized effectively, as first experiments performed on a simplified test bed have shown. Further tests proved that a prototype of the novel sound intensity probe can be calibrated.

  3. Period of vibration of axially vibrating truly nonlinear rod

    Science.gov (United States)

    Cveticanin, L.

    2016-07-01

    In this paper the axial vibration of a muscle whose fibers are parallel to the direction of muscle compression is investigated. The model is a clamped-free rod with a strongly nonlinear elastic property. Axial vibration is described by a nonlinear partial differential equation. A solution of the equation is constructed for special initial conditions by using the method of separation of variables. The partial differential equation is separated into two uncoupled strongly nonlinear second order differential equations. Both equations, with displacement function and with time function are exactly determined. Exact solutions are given in the form of inverse incomplete and inverse complete Beta function. Using boundary and initial conditions, the frequency of vibration is obtained. It has to be mentioned that the determined frequency represents the exact analytic description for the axially vibrating truly nonlinear clamped-free rod. The procedure suggested in this paper is applied for calculation of the frequency of the longissimus dorsi muscle of a cow. The influence of elasticity order and elasticity coefficient on the frequency property is tested.

  4. 30 CFR 57.19026 - Drum end attachment.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Drum end attachment. 57.19026 Section 57.19026... Wire Ropes § 57.19026 Drum end attachment. (a) For drum end attachment, wire rope shall be attached— (1... bolts, clamps, or wedges, provided that the attachment is a design feature of the hoist drum....

  5. 30 CFR 56.19026 - Drum end attachment.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Drum end attachment. 56.19026 Section 56.19026... Ropes § 56.19026 Drum end attachment. (a) For drum end attachment, wire rope shall be attached— (1... bolts, clamps, or wedges, provided that the attachment is a design feature of the hoist drum....

  6. 30 CFR 75.1436 - Drum end attachment.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Drum end attachment. 75.1436 Section 75.1436... attachment. (a) For drum end attachment, wire rope shall be attached— (1) Securely by clips after making one... that the attachment is a design feature of the hoist drum. Design feature means either the...

  7. Attachment and the Processing of Social Information in Adolescence

    Science.gov (United States)

    Dykas, Matthew J.; Cassidy, Jude

    2007-01-01

    A key proposition of attachment theory is that experience-based cognitive representations of attachment, often referred to as internal working models of attachment, influence the manner in which individuals process attachment-relevant social information (Bowlby, 1969/1982, 1973, 1980; Bretherton & Munholland, 1999; Main, Kaplan, & Cassidy, 1985).…

  8. An Attachable Electromagnetic Energy Harvester Driven Wireless Sensing System Demonstrating Milling-Processes and Cutter-Wear/Breakage-Condition Monitoring.

    Science.gov (United States)

    Chung, Tien-Kan; Yeh, Po-Chen; Lee, Hao; Lin, Cheng-Mao; Tseng, Chia-Yung; Lo, Wen-Tuan; Wang, Chieh-Min; Wang, Wen-Chin; Tu, Chi-Jen; Tasi, Pei-Yuan; Chang, Jui-Wen

    2016-02-23

    An attachable electromagnetic-energy-harvester driven wireless vibration-sensing system for monitoring milling-processes and cutter-wear/breakage-conditions is demonstrated. The system includes an electromagnetic energy harvester, three single-axis Micro Electro-Mechanical Systems (MEMS) accelerometers, a wireless chip module, and corresponding circuits. The harvester consisting of magnets with a coil uses electromagnetic induction to harness mechanical energy produced by the rotating spindle in milling processes and consequently convert the harnessed energy to electrical output. The electrical output is rectified by the rectification circuit to power the accelerometers and wireless chip module. The harvester, circuits, accelerometer, and wireless chip are integrated as an energy-harvester driven wireless vibration-sensing system. Therefore, this completes a self-powered wireless vibration sensing system. For system testing, a numerical-controlled machining tool with various milling processes is used. According to the test results, the system is fully self-powered and able to successfully sense vibration in the milling processes. Furthermore, by analyzing the vibration signals (i.e., through analyzing the electrical outputs of the accelerometers), criteria are successfully established for the system for real-time accurate simulations of the milling-processes and cutter-conditions (such as cutter-wear conditions and cutter-breaking occurrence). Due to these results, our approach can be applied to most milling and other machining machines in factories to realize more smart machining technologies.

  9. An Attachable Electromagnetic Energy Harvester Driven Wireless Sensing System Demonstrating Milling-Processes and Cutter-Wear/Breakage-Condition Monitoring.

    Science.gov (United States)

    Chung, Tien-Kan; Yeh, Po-Chen; Lee, Hao; Lin, Cheng-Mao; Tseng, Chia-Yung; Lo, Wen-Tuan; Wang, Chieh-Min; Wang, Wen-Chin; Tu, Chi-Jen; Tasi, Pei-Yuan; Chang, Jui-Wen

    2016-01-01

    An attachable electromagnetic-energy-harvester driven wireless vibration-sensing system for monitoring milling-processes and cutter-wear/breakage-conditions is demonstrated. The system includes an electromagnetic energy harvester, three single-axis Micro Electro-Mechanical Systems (MEMS) accelerometers, a wireless chip module, and corresponding circuits. The harvester consisting of magnets with a coil uses electromagnetic induction to harness mechanical energy produced by the rotating spindle in milling processes and consequently convert the harnessed energy to electrical output. The electrical output is rectified by the rectification circuit to power the accelerometers and wireless chip module. The harvester, circuits, accelerometer, and wireless chip are integrated as an energy-harvester driven wireless vibration-sensing system. Therefore, this completes a self-powered wireless vibration sensing system. For system testing, a numerical-controlled machining tool with various milling processes is used. According to the test results, the system is fully self-powered and able to successfully sense vibration in the milling processes. Furthermore, by analyzing the vibration signals (i.e., through analyzing the electrical outputs of the accelerometers), criteria are successfully established for the system for real-time accurate simulations of the milling-processes and cutter-conditions (such as cutter-wear conditions and cutter-breaking occurrence). Due to these results, our approach can be applied to most milling and other machining machines in factories to realize more smart machining technologies. PMID:26907297

  10. An Attachable Electromagnetic Energy Harvester Driven Wireless Sensing System Demonstrating Milling-Processes and Cutter-Wear/Breakage-Condition Monitoring

    Directory of Open Access Journals (Sweden)

    Tien-Kan Chung

    2016-02-01

    Full Text Available An attachable electromagnetic-energy-harvester driven wireless vibration-sensing system for monitoring milling-processes and cutter-wear/breakage-conditions is demonstrated. The system includes an electromagnetic energy harvester, three single-axis Micro Electro-Mechanical Systems (MEMS accelerometers, a wireless chip module, and corresponding circuits. The harvester consisting of magnets with a coil uses electromagnetic induction to harness mechanical energy produced by the rotating spindle in milling processes and consequently convert the harnessed energy to electrical output. The electrical output is rectified by the rectification circuit to power the accelerometers and wireless chip module. The harvester, circuits, accelerometer, and wireless chip are integrated as an energy-harvester driven wireless vibration-sensing system. Therefore, this completes a self-powered wireless vibration sensing system. For system testing, a numerical-controlled machining tool with various milling processes is used. According to the test results, the system is fully self-powered and able to successfully sense vibration in the milling processes. Furthermore, by analyzing the vibration signals (i.e., through analyzing the electrical outputs of the accelerometers, criteria are successfully established for the system for real-time accurate simulations of the milling-processes and cutter-conditions (such as cutter-wear conditions and cutter-breaking occurrence. Due to these results, our approach can be applied to most milling and other machining machines in factories to realize more smart machining technologies.

  11. Localized vibrations: moles in structure-land

    Science.gov (United States)

    van der Maas, John H.

    1992-03-01

    Functional groups reveal specific information about their direct surroundings; in fact, they form the moles, the undercover agents, in molecules. However, as with agents, the information is produced in coded form (spectral data) so one has to know the code in detail before the message is completely understood. The substantially improved accuracy (wavenumber, intensity) and sensitivity brought about by FT-instruments, in combination with computer software, offer extended spectral information. Functional groups can now be examined in great detail. Obviously the amount of deducible structural items is group dependent, implying that one has to pursue the probing qualities of a functionality prior to use. The OH-group, and more in particular the OH-stretching vibration, proves to be an extremely good mole. Its potentials are demonstrated on conformational studies of various saturated alcohols, the presence of OH(DOT)(DOT)(DOT)(pi) bridges, the strength and type of OH(DOT)(DOT)(DOT)O bridges, all in an apolar solvent, and on the disclosure of different hydrogen bonds in some solid samples.

  12. Noncontact vibration measurements using magnetoresistive sensing elements

    Science.gov (United States)

    Tomassini, R.; Rossi, G.

    2016-06-01

    Contactless instrumentations is more and more used in turbomachinery testing thanks to the non-intrusive character and the possibility to monitor all the components of the machine at the same time. Performances of blade tip timing (BTT) measurement systems, used for noncontact turbine blade vibration measurements, in terms of uncertainty and resolution are strongly affected by sensor characteristics and processing methods. The sensors used for BTT generate pulses, used for precise measurements of turbine blades time of arrival. Nowadays proximity sensors used in this application are based on optical, capacitive, eddy current and microwave measuring principle. Pressure sensors has been also tried. This paper summarizes the results achieved using a novel instrumentation based on the magnetoresistive sensing elements. The characterization of the novel probe has been already published. The measurement system was validated in test benches and in a real jet-engine comparing different sensor technologies. The whole instrumentation was improved. The work presented in this paper focuses on the current developments. In particular, attention is given to the data processing software and new sensor configurations.

  13. Interrogating selectivity in catalysis using molecular vibrations.

    Science.gov (United States)

    Milo, Anat; Bess, Elizabeth N; Sigman, Matthew S

    2014-03-13

    The delineation of molecular properties that underlie reactivity and selectivity is at the core of physical organic chemistry, and this knowledge can be used to inform the design of improved synthetic methods or identify new chemical transformations. For this reason, the mathematical representation of properties affecting reactivity and selectivity trends, that is, molecular parameters, is paramount. Correlations produced by equating these molecular parameters with experimental outcomes are often defined as free-energy relationships and can be used to evaluate the origin of selectivity and to generate new, experimentally testable hypotheses. The premise behind successful correlations of this type is that a systematically perturbed molecular property affects a transition-state interaction between the catalyst, substrate and any reaction components involved in the determination of selectivity. Classic physical organic molecular descriptors, such as Hammett, Taft or Charton parameters, seek to independently probe isolated electronic or steric effects. However, these parameters cannot address simultaneous, non-additive variations to more than one molecular property, which limits their utility. Here we report a parameter system based on the vibrational response of a molecule to infrared radiation that can be used to mathematically model and predict selectivity trends for reactions with interlinked steric and electronic effects at positions of interest. The disclosed parameter system is mechanistically derived and should find broad use in the study of chemical and biological systems. PMID:24622199

  14. Development of Lathe Attachment for a CNC Machine

    Science.gov (United States)

    Roy, V.; Kumar, S.

    2013-04-01

    A lathe attachment has been developed for an existing CNC machine (installed with rapid prototyping attachment) using conceptual design. The CNC machine operates on mechatronic controls and a computer interface called CAMSOFT, and is used as a CNC Lathe after installing the respective attachment to it. The conceptual design phase, starts from an idea and different components of the lathe are designed as attachment using CAD modelling and is followed by fabrication phase. The lathe attachment is successfully developed and is installed to the CNC machine. The working of the CNC Lathe attachment is checked by making some machining operation like turning and thread cutting. The machining operations are successfully done. The CNC machine becomes multifunctional with the presently developed lathe attachment and the existing RP (rapid prototyping) attachment, and can be used accordingly by installing the respective attachment to it. The CNC machine is useful for carrying research work in both the fields, when installed with the appropriate attachment.

  15. Predicting Statistical Distributions of Footbridge Vibrations

    DEFF Research Database (Denmark)

    Pedersen, Lars; Frier, Christian

    2009-01-01

    The paper considers vibration response of footbridges to pedestrian loading. Employing Newmark and Monte Carlo simulation methods, a statistical distribution of bridge vibration levels is calculated modelling walking parameters such as step frequency and stride length as random variables...

  16. 33 CFR 159.103 - Vibration test.

    Science.gov (United States)

    2010-07-01

    ...) POLLUTION MARINE SANITATION DEVICES Design, Construction, and Testing § 159.103 Vibration test. The device... subjected to a sinusoidal vibration for a period of 12 hours, 4 hours in each of the x, y, and z planes,...

  17. Characteristics of Vibration Induced by Cavitation

    Institute of Scientific and Technical Information of China (English)

    WANG Guo-yu; TAO Lei; LIU Shu-yan; QIAN Jian-jun

    2005-01-01

    Cavitation-induced vibration characteristics and the relations between the vibration and cavitation are studied. Cavitation vibrations are measured around a model hollow-jet valve by an accelerometer under cavitating and non-cavitating conditions. The measurement data is analyzed by FFT method. The corresponding cavitating flow patterns are photographed by a high-speed camera with an xenon flash lamp. The frequency band of the vibration induced by cavitation is determined. To compare the vibration intensities under different cavitation conditions, a definition of vibration acceleration level is introduced based on power spectral density of the vibration. By the analysis of vibration, the definitions of characteristic cavitation number are suggested. According to these cavitation numbers, the cavitation process is divided into three stages, that is, incipient cavitation, subcavitation and supercavitation.

  18. On the vibrations localization in building structures

    Directory of Open Access Journals (Sweden)

    V.V. Lalin

    2012-08-01

    Full Text Available The article considers the local vibrations of elements of building structures. It is shown that under certain conditions, external influences cause vibrations of only some structural elements, but the whole structure stay in quiescence condition. The classification of local vibrations by the frequency characteristic is proposed. The limitation of spectrum of mechanical vibrations for buildings with structural damping due to the presence of dry friction forces is shown.

  19. Dissipation of vibration in rough contact

    OpenAIRE

    Le Bot, Alain; Bou-Chakra, Elie; Michon, Guilhem

    2011-01-01

    The relationship which links the normal vibration occurring during the sliding of rough surfaces and the nominal contact area is investigated. Two regimes are found. In the first one, the vibrational level does not depend on the contact area, while in the second one, it is propor- tional to the contact area. A theoretical model is proposed. It is based on the assumption that the vibrational level results from a competition between two processes of vibration damping, the internal damping of th...

  20. Work ability in vibration-exposed workers

    OpenAIRE

    Gerhardsson, L; Hagberg, M

    2014-01-01

    Background Hand–arm vibration exposure may cause hand–arm vibration syndrome (HAVS) including sensorineural disturbances. Aims To investigate which factors had the strongest impact on work ability in vibration-exposed workers. Methods A cross-sectional study in which vibration-exposed workers referred to a department of occupational and environmental medicine were compared with a randomized sample of unexposed subjects from the general population of the city of Gothenburg. All participants un...

  1. Resonant vibration control of rotating beams

    DEFF Research Database (Denmark)

    Svendsen, Martin Nymann; Krenk, Steen; Høgsberg, Jan Becker

    2011-01-01

    Rotatingstructures,like e.g.wind turbine blades, may be prone to vibrations associated with particular modes of vibration. It is demonstrated, how this type of vibrations can be reduced by using a collocated sensor–actuator system, governed by a resonant controller. The theory is here demonstrated...... modal connectivity, only very limited modal spill-over is generated. The controller acts by resonance and therefore has only a moderate energy consumption, and successfully reduces modal vibrations at the resonance frequency....

  2. Vibrational relaxation in pyridine upon supersonic expansion

    Science.gov (United States)

    Maris, Assimo; Favero, Laura B.; Danieli, Roberto; Favero, Paolo G.; Caminati, Walther

    2000-11-01

    The rotational spectra of five vibrational states of pyridine have been assigned and measured by millimeter wave absorption spectroscopy in a supersonic expansion. The intensities of the lines of the vibrational satellites with respect to the ground state after the supersonic expansion depend on the kind of carrier gas, backing pressure, pyridine concentration, and symmetry of the rotational and vibrational states. Several rotational transitions of the vibrational satellites have also been measured in a conventional cell to complete the spectral assignment.

  3. Direct Probes of 4 nm Diameter Gold Nanoparticles Interacting with Supported Lipid Bylayers

    Energy Technology Data Exchange (ETDEWEB)

    Troiano, Julianne; Olenick, Laura L.; Kuech, Thomas R.; Melby, Eric S.; Hu, Dehong; Lohse, Samuel E.; Mensch, Arielle C.; Dogangun, Merve; Vartanian, Arlane M.; Torelli, Marco; Ehimiaghe, Eseohi; Walter, Stephanie R.; Fu, Li; Anderton, Christopher R.; Zhu, Zihua; Wang, Hongfei; Orr, Galya; Murphy, Catherine; Hamers, Robert J.; Pedersen, Joel A.; Geiger, Franz M.

    2015-01-08

    Interfacial charge densities and potentials are determined for silica-supported phospholipid bilayers formed from lipids having zwitterionic, negatively charged, and positively charged headgroups. Quartz crystal microbalance with dissipation (QCM-D), fluorescence recovery after photobleaching (FRAP), and atomic force microscopy demonstrate the presence of well-formed supported lipid bilayers, which, as probed by vibrational sum frequency generation (SFG), undergo negligible structural changes along their alkyl chains when NaCl concentration is raised from 0.001 to 0.1 M. From second harmonic generation (SHG) measurements we estimate that each zwitterionic headgroup of the bilayer formed from pure DOPC is associated with an apparent charge of -0.028(+0.008/-0.007)×10-¹⁹C, corresponding to 1.8 ± 0.5 % of an elementary negative charge. Moreover, we show that a supported lipid bilayer carrying an apparent negative interfacial potential may interact with not just positively charged 4-nm diameter gold nanoparticles but also negatively charged gold nanoparticles. In this latter case, charge-charge repulsion does not appear to inhibit particle-bilayer interactions and is likely overcome by multivalent interactions that are estimated to involve 3-5 hydrogen-bond equivalents. FRAP, QCM-D, and SFG measurements indicate that the bilayers remain intact under the conditions of the experiments. SHG charge screening experiments are consistent with an apparent zero net charge density associated with the positively charged gold nanoparticles when they are attached to a supported lipid bilayer carrying an apparent negative potential. The results presented here serve to benchmark experimental and computational studies of the nano-bio interface.

  4. Childhood Abuse and Attachment Styles of Adolescents

    Science.gov (United States)

    Karakus, Ozlem

    2012-01-01

    Introduction: The fact that emotional and social experiences in early childhood period within the family influence the experiences in adolescence and adulthood (communication skills, interpersonal relations) is not a new case. Therefore, the aim of this study is to examine the relationship between childhood abuse and attachment styles. Method: The…

  5. Should Charity Donations Have Strings Attached?

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The commonly held belief among most people is that acts of charity are carried out with no thought of getting something in return, or of attaching conditions to those who receive donations. It’s perhaps for this rea- son that events surrounding the Henan Charity Federation’s recent decision to add an agenda to students’ financial aid caused such a public outcry.

  6. Hidden Regulators in Attachment, Separation, and Loss.

    Science.gov (United States)

    Hofer, Myron A.

    1994-01-01

    This essay discusses the similarities between animal behavior and human attachment behavior demonstrated by infants and their mothers. The provision of warmth, the tactile and olfactory stimulation of the mother's physical interactions, and the oral sensory and absorptive consequences of nursing are found to provide specific and independent…

  7. Ammonium and attachment of Rhodopirellula baltica.

    Science.gov (United States)

    Frank, Carsten S; Langhammer, Philipp; Fuchs, Bernhard Maximilian; Harder, Jens

    2011-05-01

    A dimorphic life cycle has been described for the planctomycete Rhodopirellula baltica SH1(T), with juvenile motile, free-swimming cells and adult sessile, attached-living cells. However, attachment as a response to environmental factors was not investigated. We studied the response of R. baltica to nitrogen limitation. In batch cultures, ammonium limitation coincided with a dominance of free-swimming cells and a low number of aggregates. Flow cytometry revealed a quantitative shift with increasing ammonium availability, from single cells towards attached cells in large aggregates. During growth of R. baltica on glucose and ammonium in chemostats, an ammonium addition caused a macroscopic change of the growth behaviour, from homogeneous growth in the liquid phase to a biofilm on the borosilicate glass wall of the chemostat vessel. Thus, an ammonium limitation-a carbon to nitrogen supply ratio of 30:1-sustained free-living growth without aggregate formation. A sudden increase in ammonium supply induced sessile growth of R. baltica. These observations reveal a response of Rhodopirellula baltica cells to ammonium: they abandon the free-swimming life, attach to particles and form biofilms. PMID:21340506

  8. No Strings Attached: Open Source Solutions

    Science.gov (United States)

    Fredricks, Kathy

    2009-01-01

    Imagine downloading a new software application and not having to worry about licensing, finding dollars in the budget, or incurring additional maintenance costs. Imagine finding a Web design tool in the public domain--free for use. Imagine major universities that provide online courses with no strings attached. Imagine online textbooks without a…

  9. Maternal anxiety, maternal sensitivity, and attachment

    NARCIS (Netherlands)

    Stevenson-Hinde, J.; Chicot, R.; Schouldice, A.; Hinde, C.A.

    2013-01-01

    Previous research has related maternal anxiety to insecurity of attachment. Here we ask whether different aspects of maternal sensitivity mediate this link. From a community sample of intact families with 1-3 children, mothers with 4.5-year-olds were selected for low, medium, or high anxiety levels

  10. Maternal anxiety, maternal sensitivity, and attachment

    NARCIS (Netherlands)

    Stevenson-Hinde, Joan; Chicot, Rebecca; Shouldice, Anne; Hinde, Camilla A.

    2016-01-01

    Previous research has related maternal anxiety to insecurity of attachment. Here we ask whether different aspects of maternal sensitivity mediate this link. From a community sample of intact families with 1-3 children, mothers with 4.5-year-olds were selected for low, medium, or high anxiety leve

  11. Bowlby's attachment theory: implications for health visiting.

    Science.gov (United States)

    Partis, M

    2000-10-01

    This article reviews the current state of research in attachment theory. It also examines the relations between attachment, child care and development, and the significance of attachment to adult functioning and well-being. It seems likely that humans need close emotional relationships or bonds with others. This need applies particularly to infants, who look to parents or other care givers for love and security. The best-known psychological explanation of this need is attachment theory, which has been influential in increasing our understanding of the early mother-infant relationship, and in the formulation of guidelines for child care (Melhuish, 1998). Good-quality parental care may be difficult to define, and questions remain regarding the nature of child care and the consequences that it can have for later development. This article concludes with a discussion of the possible implications for health-visitor intervention within families, which are intended to improve the quality of the relationship between parents or care givers and the infant.

  12. Attachment Styles, Abuse Experiences and Depression

    Science.gov (United States)

    Gunduz, Bulent; Capri, Burhan; Akbay, Sinem Evin; Tunc, Aygul

    2013-01-01

    This study aims to examine the relationship between abuse experiences, depression and attachment styles. The data for this study was collected from 251 students (123 females and 128 males) who attend Mersin University. As a part of the data collection, students completed the Experiences in Affiliation Inventory, Childhood Trauma Scale and Brief…

  13. Probing intermolecular couplings in liquid water with two-dimensional infrared photon echo spectroscopy

    Science.gov (United States)

    Paarmann, A.; Hayashi, T.; Mukamel, S.; Miller, R. J. D.

    2008-05-01

    Two-dimensional infrared photon echo and pump probe studies of the OH stretch vibration provide a sensitive probe of the correlations and couplings in the hydrogen bond network of liquid water. The nonlinear response is simulated using numerical integration of the Schrödinger equation with a Hamiltonian constructed to explicitly treat intermolecular coupling and nonadiabatic effects in the highly disordered singly and doubly excited vibrational exciton manifolds. The simulated two-dimensional spectra are in close agreement with our recent experimental results. The high sensitivity of the OH stretch vibration to the bath dynamics is found to arise from intramolecular mixing between states in the two-dimensional anharmonic OH stretch potential. Surprisingly small intermolecular couplings reproduce the experimentally observed intermolecular energy transfer times.

  14. Infant attachment, adult attachment, and maternal sensitivity: revisiting the intergenerational transmission gap.

    Science.gov (United States)

    Behrens, Kazuko Y; Haltigan, John D; Bahm, Naomi I Gribneau

    2016-08-01

    This study investigated the intergenerational transmission of attachment, utilizing the Adult Attachment Interview (AAI), the Strange Situation Procedure (SSP), and the Maternal Behavioral Q-Set (MBQS). We revisited fundamental questions in attachment theory and research by examining: (1) the level of intergenerational agreement between maternal attachment representations and infant attachment security, and (2) whether maternal sensitivity serves as an intergenerational mediator between adult and infant attachment security. Significant categorical matches between the AAI and the SSP as well as mean differences for MBQS scores between adult attachment secure-insecure groups were found. Consistent with earlier intergenerational research, maternal sensitivity only partially mediated the AAI-SSP link, indicating the transmission gap remains. Consistent with recent mediation studies, using more contemporary analytical techniques, it was confirmed that maternal sensitivity did mediate the direct pathway between AAI security and SSP security. Thus, the transmission gap appears somewhat different depending on the statistical method used to measure mediation. Post hoc analyses considered mothers' childhood experiences of separation/divorce and this helped make sense of intergenerational mismatches.

  15. Comparative validity of the Adult Attachment Interview and the Adult Attachment Projective.

    Science.gov (United States)

    Jones-Mason, Karen; Allen, I Elaine; Hamilton, Steve; Weiss, Sandra J

    2015-01-01

    The Adult Attachment Interview (AAI) and the Adult Attachment Projective (AAP) purport to measure the same attachment classifications. The aims of this study were to determine the concurrent validity of the AAI and AAP, and to compare their ability to predict indicators of risk associated with socioeconomic status (SES), depression, and 5-HTTLPR genotype. Results indicated no agreement between AAI and AAP attachment classifications in a sample of late adolescents. As predicted, individuals classified as "unresolved" with regard to loss or trauma were significantly more likely to be of lower SES, have higher levels of depression, and have the 5-HTTLPR "ss" genotype than individuals with secure, preoccupied, or dismissing attachments. These associations, however, were only significant when attachment was classified with the AAI. Results suggest that the AAI and AAP measure different facets of attachment as a result of their unique methodologies and coding criteria. Further research is needed to support their comparability before investigators can assume that the AAP is a valid substitute for the AAI. PMID:26362584

  16. Infant attachment, adult attachment, and maternal sensitivity: revisiting the intergenerational transmission gap.

    Science.gov (United States)

    Behrens, Kazuko Y; Haltigan, John D; Bahm, Naomi I Gribneau

    2016-08-01

    This study investigated the intergenerational transmission of attachment, utilizing the Adult Attachment Interview (AAI), the Strange Situation Procedure (SSP), and the Maternal Behavioral Q-Set (MBQS). We revisited fundamental questions in attachment theory and research by examining: (1) the level of intergenerational agreement between maternal attachment representations and infant attachment security, and (2) whether maternal sensitivity serves as an intergenerational mediator between adult and infant attachment security. Significant categorical matches between the AAI and the SSP as well as mean differences for MBQS scores between adult attachment secure-insecure groups were found. Consistent with earlier intergenerational research, maternal sensitivity only partially mediated the AAI-SSP link, indicating the transmission gap remains. Consistent with recent mediation studies, using more contemporary analytical techniques, it was confirmed that maternal sensitivity did mediate the direct pathway between AAI security and SSP security. Thus, the transmission gap appears somewhat different depending on the statistical method used to measure mediation. Post hoc analyses considered mothers' childhood experiences of separation/divorce and this helped make sense of intergenerational mismatches. PMID:27056466

  17. Sexuality examined through the lens of attachment theory: attachment, caregiving, and sexual satisfaction.

    Science.gov (United States)

    Péloquin, Katherine; Brassard, Audrey; Lafontaine, Marie-France; Shaver, Phillip R

    2014-01-01

    Attachment researchers have proposed that the attachment, caregiving, and sexual behavioral systems are interrelated in adult love relationships (Mikulincer & Shaver, 2007 ). This study examined whether aspects of partners' caregiving (proximity, sensitivity, control, compulsive caregiving) mediated the association between their attachment insecurities (anxiety and avoidance) and each other's sexual satisfaction in two samples of committed couples (Study 1: 126 cohabiting or married couples from the general community; Study 2: 55 clinically distressed couples). Partners completed the Experiences in Close Relationships measure (Brennan, Clark, & Shaver, 1998 ), the Caregiving Questionnaire (Kunce & Shaver, 1994 ), and the Global Measure of Sexual Satisfaction (Lawrance & Byers, 1998 ). Path analyses based on the actor-partner interdependence model (APIM) revealed that caregiving proximity mediated the association between low attachment avoidance and partners' sexual satisfaction in distressed and nondistressed couples. Sensitivity mediated this association in nondistressed couples only. Control mediated the association between men's insecurities (attachment-related avoidance and anxiety) and their partners' low sexual satisfaction in nondistressed couples. Attachment anxiety predicted compulsive caregiving, but this caregiving dimension was not a significant mediator. These results are discussed in light of attachment theory and their implications for treating distressed couples.

  18. Model for resonant plasma probe.

    Energy Technology Data Exchange (ETDEWEB)

    Warne, Larry Kevin; Johnson, William Arthur; Hebner, Gregory Albert; Jorgenson, Roy E.; Coats, Rebecca Sue

    2007-04-01

    This report constructs simple circuit models for a hairpin shaped resonant plasma probe. Effects of the plasma sheath region surrounding the wires making up the probe are determined. Electromagnetic simulations of the probe are compared to the circuit model results. The perturbing effects of the disc cavity in which the probe operates are also found.

  19. A small dimension intraoperative probe

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    This article introduces the usage of the intraoperative probe in surgical based on RGS and proposes one method to design the probe. Also, a charge-sensitive preamplifier used in semiconductor detector was constructed which can reduce the dimension of the probe. At last the probe is tested by some animal experiments. Results showed that the property of this system are reliable.

  20. Vibration Theory, Vol. 1A

    DEFF Research Database (Denmark)

    Nielsen, Søren R. K.

    The present collection of solved problems has been published as a supplement to the textbook Svingningsteori. Bind 1. Lineær svingningsteori,Aalborg tekniske Universitetsforlag, 1991, whicj is used in the introductory course on linear vibration theory that is being given on th e8th semester at th...

  1. Ultrafast vibrations of gold nanorings

    DEFF Research Database (Denmark)

    Kelf, T; Tanaka, Y; Matsuda, O;

    2011-01-01

    We investigate the vibrational modes of gold nanorings on a silica substrate with an ultrafast optical technique. By comparison with numerical simulations, we identify several resonances in the gigahertz range associated with axially symmetric deformations of the nanoring and substrate. We elucid...

  2. Vibrational properties of amorphous semiconductors

    International Nuclear Information System (INIS)

    A model for the lattice dynamics of a-Si1-X NX is introduced. This model is based on a Born hamiltonian, solved in the Bethe lattice approximation. Starting from the local density of vibrational states, we analize the infrared absoption spectra of this material. (author)

  3. Damping of a vibrating beam

    NARCIS (Netherlands)

    Hietanen, Jarmo; Bomer, Johan; Jonsmann, Jacques; Olthuis, Wouter; Bergveld, Piet; Kaski, Kimmo

    2000-01-01

    This study examines the vibration in a beam with one fixed end. The set-up consisted of a beam with one end clamped and a rigid plate having the same thickness of the beam, located adjacent to the unfixed end of the beam. The gap between the beam and the plate varied from 4 to 128 μm depending on th

  4. Communication: Nanosecond folding dynamics of an alpha helix: Time-dependent 2D-IR cross peaks observed using polarization-sensitive dispersed pump-probe spectroscopy

    NARCIS (Netherlands)

    M.R. Panman; C.N. van Dijk; H. Meuzelaar; S. Woutersen

    2015-01-01

    We present a simple method to measure the dynamics of cross peaks in time-resolved two-dimensional vibrational spectroscopy. By combining suitably weighted dispersed pump-probe spectra, we eliminate the diagonal contribution to the 2D-IR response, so that the dispersed pump-probe signal contains the

  5. Tailored probes for atomic force microscopy fabricated by two-photon polymerization

    Science.gov (United States)

    Göring, Gerald; Dietrich, Philipp-Immanuel; Blaicher, Matthias; Sharma, Swati; Korvink, Jan G.; Schimmel, Thomas; Koos, Christian; Hölscher, Hendrik

    2016-08-01

    3D direct laser writing based on two-photon polymerization is considered as a tool to fabricate tailored probes for atomic force microscopy. Tips with radii of 25 nm and arbitrary shape are attached to conventionally shaped micro-machined cantilevers. Long-term scanning measurements reveal low wear rates and demonstrate the reliability of such tips. Furthermore, we show that the resonance spectrum of the probe can be tuned for multi-frequency applications by adding rebar structures to the cantilever.

  6. Vibrating Beam With Spatially Periodic Stiffness

    Science.gov (United States)

    Townsend, John S.

    1989-01-01

    Report presents theoretical analysis of vibrations of simply supported beam, bending stiffness varying about steady value, sinusoidally with position along length. Problem of practical importance because related to vibrations of twisted-pair electric-power transmission lines. Twists promote nonuniform shedding of vortexes and prevents resonant accumulation of vibrational energy from wind.

  7. Rotor Vibration Reduction via Active Hybrid Bearings

    DEFF Research Database (Denmark)

    Nicoletti, Rodrigo; Santos, Ilmar

    2002-01-01

    The use of fluid power to reduce and control rotor vibration in rotating machines is investigated. An active hybrid bearing is studied, whose main objective is to reduce wear and vibration between rotating and stationary machinery parts. By injecting pressurised oil into the oil film, through...... with experiment, and simulations show the feasibility of controlling shaft vibration through this active device....

  8. THERMOPHILE ENDOSPORES HAVE RESPONSIVE EXOSPORIUM FOR ATTACHMENT

    Energy Technology Data Exchange (ETDEWEB)

    PANESSA-WARREN,B.; TORTORA,G.T.; WARREN,J.; SABATINI,R.

    1999-08-01

    Recently studies examining the colonization of Clostridial pathogens on agar and human tissue culture cells, demonstrated that (C. sporogenes ATCC 3584, C. difficile ATCC 43594 [patient isolate], C. difficile ATCC 9689 [non-clinical], C. clostridioforme [patient isolate]) bacterial spores (endospores) of the genus Clostridia have an outer membrane that becomes responsive at activation and exhibits extensions of the exosporial membrane that facilitate and maintain spore attachment to a nutritive substrate during germination and initial outgrowth of the newly developed bacterial cell. Therefore this attachment phenomenon plays an important role in insuring bacterial colonization of a surface and the initial stages of the infective process. To see if other non-clinical members of this genus also have this ability to attach to a substrate or food-source during spore germination, and how this attachment process in environmental thermophiles compares to the clinical paradigm (in relation to time sequence, exosporial membrane structure, type of attachment structures, composition of the membrane etc...), sediment samples were collected in sterile transport containers at 4 geothermal sites at Yellowstone National Park in Wyoming. Because spore forming bacteria will produce spores when conditions are unfavorable for growth, the samples were sealed and stored at 4 C. After 8 months the samples were screened for the presence of spores by light microscope examination using malachite green/safranin, and traditional endospores were identified in significant quantities from the Terrace Spring site (a 46 C lake with bacterial mats and a rapidly moving run-off channel leading to a traditional hot spring). The highest spore population was found in the top sediment and benthic water of the run-off channel, pH 8.1.

  9. Electron attachment rate constant measurement by photoemission electron attachment ion mobility spectrometry (PE-EA-IMS)

    Science.gov (United States)

    Su, Desheng; Niu, Wenqi; Liu, Sheng; Shen, Chengyin; Huang, Chaoqun; Wang, Hongmei; Jiang, Haihe; Chu, Yannan

    2012-12-01

    Photoemission electron attachment ion mobility spectrometry (PE-EA-IMS), with a source of photoelectrons induced by vacuum ultraviolet radiation on a metal surface, has been developed to study electron attachment reaction at atmospheric pressure using nitrogen as the buffer gas. Based on the negative ion mobility spectra, the rate constants for electron attachment to tetrachloromethane and chloroform were measured at ambient temperature as a function of the average electron energy in the range from 0.29 to 0.96 eV. The experimental results are in good agreement with the data reported in the literature.

  10. The Effect of Birth Order on Attachment Style According to Attachment Theory

    OpenAIRE

    BAYRAKTAR, Seda; YAHŞİ, Gülşah

    2016-01-01

    Attachment is a vital neurobiopsychological phenomenon known to be dependent on the early relationship between baby and the caregiver. It mostly develops in the first year and out of repeated patterns of the primary attachment relationship. Birth order is defined as a person's rank by age among his or her siblings. Birth order is often believed to have a profound and lasting effect on psychological development. Also it has been thought that birth order has an impact on the attachment.  In thi...

  11. [Vibration hazards in quarry workers].

    Science.gov (United States)

    Sakakibara, H; Miyao, M; Nakagawa, T; Yamada, S; Kobayashi, F; Ono, Y; Iwata, M; Hisanaga, N; Momoi, N

    1984-03-01

    Vibration hazards were surveyed in a population of quarry workers using chipping hammers and to a lesser extent, rock drills. Sixty-nine male quarry workers, aged 49.1 +/- 8.7 and exposed to vibration for 16.4 +/- 5.1 years, were surveyed in 1981-82. They were exposed to vibration for about 2-4 hours per days, mainly under a piece-work pay system. They had a high prevalence of Raynaud's phenomenon (36.2%) and numbness in upper extremities (53.6%). It is considered that the high prevalence was mainly due to large vibration levels in chipping hammers and rock drills and long daily exposure time. The attacks of Raynaud's phenomenon were found predominantly in the left hand, which held chisels, whereas the restriction of motion in the elbow was predominantly in the right arm which pushed chipping hammers. The same 49 male quarry workers in this population were also surveyed in 1976-77 and the prevalence of their complaints between 1976-77 and 1981-82 was compared. The prevalence of Raynaud's phenomenon was the same, but the frequency of the attacks increased between the two periods. The prevalence of other complaints such as numbness, pain and chills in the upper extremities also increased. Between 1976-77 and 1981-82, the prevalence of Raynaud's phenomenon, numbness, and pain in the upper extremities increased in the population of quarriers exposed to vibration for above 2.6 hours per day and 200 days per year, or 600 hours per year. On the other hand, the prevalence of these complaints mostly decreased in the population of quarriers with less exposure.

  12. Attachment: A Study of a Child's Attachment to the Teacher as an Outgrowth of Her/His Attachment to the Mother.

    Science.gov (United States)

    Houston, Ann Jespersen

    This paper reviews the literature on attachment, presents a study of child-teacher attachment, and discusses child-teacher attachment as a secondary relationship influenced by the prototype bonding between mother and child. The literature review traces the development of psychoanalytic thought regarding the mother-child relationship and examines…

  13. In-Depth Electrochemical Investigation of Surface Attachment Chemistry via Carbodiimide Coupling.

    Science.gov (United States)

    Booth, Marsilea Adela; Kannappan, Karthik; Hosseini, Ali; Partridge, Ashton

    2015-07-28

    Aminoferrocene is used as an electroactive indicator to investigate carbodiimide coupling reactions on a carboxylic acid-functionalized self-assembled monolayer. The commonly used attachment chemistry with 1-ethyl-3-(3-(dimethylamino)propyl)carbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS) is used for surface activation. A number of conditions are investigated, including EDC and NHS concentration, buffer solutions, incubation timing, and aminoferrocene concentration. Ferrocene is a well-documented electroactive species, and the number of surface-bound ferrocene species can be calculated using electrochemical methods. This capability allows determination of optimal conditions, as well as providing a method for comparing and investigating novel carboxylated surfaces. An EDC-mediated procedure with ∼5 mM EDC and NHS (1:1) made in water, with a full acid monolayer, with 250 μM aminoferrocene for 40 min was found to give the highest ferrocene attachment. An application of this is demonstrated for preparing a probe-DNA-coated surface for DNA sensing. By backfilling with aminoferrocene, a differential quantification of the amount of probe DNA available for sensing can be obtained. This provides an elegant method to monitor an important aspect, namely, probe surface characterization, which will be highly useful for biosensing purposes. PMID:26107592

  14. IMPROVED FABRICATION METHOD FOR CARBON NANOTUBE PROBE OF ATOMIC FORCE MICROSCOPY(AFM)

    Institute of Scientific and Technical Information of China (English)

    XU Zongwei; DONG Shen; GUO Liqiu; ZHAO Qingliang

    2006-01-01

    An improved arc discharge method is developed to fabricate carbon nanotube probe of atomic force microscopy (AFM) here. First, silicon probe and carbon nanotube are manipulated under an optical microscope by two high precision microtranslators. When silicon probe and carbon nanotube are very close, several tens voltage is applied between them. And carbon nanotube is divided and attached to the end of silicon probe, which mainly due to the arc welding function.Comparing with the arc discharge method before, the new method here needs no coat silicon probe with metal film in advance, which can greatly reduce the fabrication's difficulty. The fabricated carbon nanotube probe shows good property of higher aspect ratio and can more accurately reflect the true topography of silicon grating than silicon probe. Under the same image drive force, carbon nanotube probe had less indentation depth on soft triblock copolymer sample than silicon probe. This showed that carbon nanotube probe has lower spring constant and less damage to the scan sample than silicon probe.

  15. Multispectral imaging probe

    Science.gov (United States)

    Sandison, David R.; Platzbecker, Mark R.; Descour, Michael R.; Armour, David L.; Craig, Marcus J.; Richards-Kortum, Rebecca

    1999-01-01

    A multispectral imaging probe delivers a range of wavelengths of excitation light to a target and collects a range of expressed light wavelengths. The multispectral imaging probe is adapted for mobile use and use in confined spaces, and is sealed against the effects of hostile environments. The multispectral imaging probe comprises a housing that defines a sealed volume that is substantially sealed from the surrounding environment. A beam splitting device mounts within the sealed volume. Excitation light is directed to the beam splitting device, which directs the excitation light to a target. Expressed light from the target reaches the beam splitting device along a path coaxial with the path traveled by the excitation light from the beam splitting device to the target. The beam splitting device directs expressed light to a collection subsystem for delivery to a detector.

  16. Predicting Nuclear Resonance Vibrational Spectra of [Fe(OEP)(NO)].

    Science.gov (United States)

    Peng, Qian; Pavlik, Jeffrey W; Scheidt, W Robert; Wiest, Olaf

    2012-01-10

    Nuclear Resonance Vibrational Spectroscopy (NRVS) is a sensitive vibrational probe for biologically important heme complexes. The exquisite sensitivity of the NRVS data to the electronic structure provides detailed insights into the nature of these interesting compounds, but requires highly accurate computational methods for the mode assignments. To determine the best combinations of density functionals and basis sets, a series of benchmark DFT calculations on the previously characterized complex [Fe(OEP)NO] (OEP(2-)=octaethylporphyrinatio dianion) were performed. A test set of 21 methodology combinations including 8 functionals (BP86, mPWPW91, B3LYP, PBE1PBE, M062X, M06L, LC-BP86 and ωB97X-D) and 5 basis set (VTZ, TZVP, Lanl2DZ for iron and 6-31G*, 6-31+G* for other atoms) was carried out to calculate electronic structures and vibrational frequencies. We also implemented the conversion of frequency calculations into orientation-selective mode composition factors (e(2)), which can used to simulate the Vibrational Density Of States (VDOS) using Gaussian normal distribution functions. These use a series of user-friendly scripts for their application to NRVS. The structures as well as the isotropic and anisotropic NRVS of [Fe(OEP)NO] obtained with the M06L functional with a variety of basis sets are found to best reproduce the available experimental data, followed by B3LYP/LanL2DZ calculations. Other density functionals and basis sets do not produce the same level of accuracy. The noticeably worse agreement between theory and experiment for the out-plane NRVS compared with the excellent performance of the M06L functional for the in-plane prediction is attributed to deficiencies of the physical model rather than the computational methodology. PMID:23204948

  17. S-shape spring sensor: Sensing specific low-frequency vibration by energy harvesting

    Science.gov (United States)

    Zhang, Lan; Lu, Jian; Takei, Ryohei; Makimoto, Natsumi; Itoh, Toshihiro; Kobayashi, Takeshi

    2016-08-01

    We have developed a Si-based microelectromechanical systems sensor with high sensitivity for specific low-frequency vibration-sensing and energy-harvesting applications. The low-frequency vibration sensor contains a disk proof mass attached to two or three lead zirconate titanate (PZT) S-shape spring flexures. To obtain a faster and less expensive prototype, the design and optimization of the sensor structure are studied via finite-element method analysis. To validate the sensor structure to detect low-frequency vibration, the effects of geometrical dimensions, including the width and diameter of the S-shape spring of the proof mass, were analyzed and measured. The functional features, including the mechanical property and electrical performance of the vibration sensor, were evaluated. The results demonstrated that a very low resonant frequency of 0.2g can be typically achieved. Given a low-frequency vibration sensor with ideal performance and mass fabrication, many advanced civilian and industrial applications can be possibly realized.

  18. S-shape spring sensor: Sensing specific low-frequency vibration by energy harvesting.

    Science.gov (United States)

    Zhang, Lan; Lu, Jian; Takei, Ryohei; Makimoto, Natsumi; Itoh, Toshihiro; Kobayashi, Takeshi

    2016-08-01

    We have developed a Si-based microelectromechanical systems sensor with high sensitivity for specific low-frequency vibration-sensing and energy-harvesting applications. The low-frequency vibration sensor contains a disk proof mass attached to two or three lead zirconate titanate (PZT) S-shape spring flexures. To obtain a faster and less expensive prototype, the design and optimization of the sensor structure are studied via finite-element method analysis. To validate the sensor structure to detect low-frequency vibration, the effects of geometrical dimensions, including the width and diameter of the S-shape spring of the proof mass, were analyzed and measured. The functional features, including the mechanical property and electrical performance of the vibration sensor, were evaluated. The results demonstrated that a very low resonant frequency of 0.2g can be typically achieved. Given a low-frequency vibration sensor with ideal performance and mass fabrication, many advanced civilian and industrial applications can be possibly realized. PMID:27587151

  19. Mitigation of Ice-Induced Vibrations for Offshore Platforms Using Tuned Mass Damper

    Institute of Scientific and Technical Information of China (English)

    ZHANG Li; YUE Qian-jin; ZHANG Wen-shou

    2008-01-01

    The problems of ice-induced vibration have been noticed and concerned since the 1960s, but it has not been well resolved. One reason is that the dynamic interaction between ice and structure is so complicated that practical ice force model has not been developed. The recent full-scale tests conducted on jacket platforms in the Bohai Sea presented that ice could cause intense vibrations which endanger the facilities on the deck and make discomfort for the crew. In this paper, the strategy of mitigation of ice-induced offshore structure vibration is discussed. Based on field observations and understanding of the interaction between ice and structure, the absorption mitigation method to suppress ice-induced vibration is presented. The numerical simulations were conducted for a simplified model of platform attached with a Tuned Mass Damper (TMD) under ice force function and ice force time history. The simulation results show that TMD can favorably reduce ice-induced vibrations, therefore, it can be considered to be an alternative approach to utilize. Finally, the application possibilities of utilizing TMDs on other miniature offshore structures in ice-covered areas of marginal oil fields are discussed.

  20. Vibration measurement and modal analysis for tunneller

    Institute of Scientific and Technical Information of China (English)

    HUANG Min; WU Miao; WEI Ren-zhi

    2001-01-01

    In this paper, the method of vibration measurement and modal analysis for AM~50 Tunneller machine is presented. When the machine was used for cutting man-made coal bed and real coal bed, the vibration of the machine was measured and the results of signal analysis show that the vibration characteristics under the two kinds of working situations are similar. The modal model of the machine is established, and then, the intrinsic vibration characteristics of AM50 tunneller are investigated by means of the method of experimental modal analysis. The vibration response simulation under a set of loading spectra measured is carried out by force response simulation software.

  1. A curved vitrectomy probe.

    Science.gov (United States)

    Chalam, K V; Shah, Vinay A; Tripathi, Ramesh C

    2004-01-01

    A curved vitrectomy probe for better accessibility of the peripheral retina in phakic eyes is described. The specially designed curved vitrectomy probe has a 20-gauge pneumatic cutter. The radius of curvature at the shaft is 19.4 mm and it is 25 mm long. The ora serrata is accessed through a 3.0- or 4.0-mm sclerotomy in phakic eyes without touching the crystalline lens. Use of this instrument avoids inadvertent trauma to the clear lens in phakic eyes requiring vitreous base excision. This curved vitrectomy instrument complements wide-angle viewing systems and endoscopes for safe surgical treatment of peripheral retinal pathology in phakic eyes. PMID:15185799

  2. Porcine dentin sialoprotein glycosylation and glycosaminoglycan attachments

    Directory of Open Access Journals (Sweden)

    Yamakoshi Fumiko

    2011-02-01

    Full Text Available Abstract Background Dentin sialophosphoprotein (Dspp is a multidomain, secreted protein that is critical for the formation of tooth dentin. Mutations in DSPP cause inherited dentin defects categorized as dentin dysplasia type II and dentinogenesis imperfecta type II and type III. Dentin sialoprotein (Dsp, the N-terminal domain of dentin sialophosphoprotein (Dspp, is a highly glycosylated proteoglycan, but little is known about the number, character, and attachment sites of its carbohydrate moieties. Results To identify its carbohydrate attachment sites we isolated Dsp from developing porcine molars and digested it with endoproteinase Glu-C or pronase, fractionated the digestion products, identified fractions containing glycosylated peptides using a phenol sulfuric acid assay, and characterized the glycopeptides by N-terminal sequencing, amino acid analyses, or LC/MSMS. To determine the average number of sialic acid attachments per N-glycosylation, we digested Dsp with glycopeptidase A, labeled the released N-glycosylations with 2-aminobenzoic acid, and quantified the moles of released glycosylations by comparison to labeled standards of known concentration. Sialic acid was released by sialidase digestion and quantified by measuring β-NADH reduction of pyruvic acid, which was generated stoichiometrically from sialic acid by aldolase. To determine its forms, sialic acid released by sialidase digestion was labeled with 1,2-diamino-4,5-methyleneoxybenzene (DMB and compared to a DMB-labeled sialic acid reference panel by RP-HPLC. To determine the composition of Dsp glycosaminoglycan (GAG attachments, we digested Dsp with chondroitinase ABC and compared the chromotagraphic profiles of the released disaccharides to commercial standards. N-glycosylations were identified at Asn37, Asn77, Asn136, Asn155, Asn161, and Asn176. Dsp averages one sialic acid per N-glycosylation, which is always in the form of N-acetylneuraminic acid. O-glycosylations were

  3. Detection of gas atoms via vibration of graphenes

    Science.gov (United States)

    Arash, Behrouz; Wang, Quan; Duan, Wen Hui

    2011-06-01

    The application of single-layered graphene sheets as mass sensors in detection of noble gases via a vibration analysis of graphenes is investigated using molecular dynamics simulations. An index based on frequency shifts of the graphenes attached by the distinct noble gas atoms is defined and examined to measure the sensitivity of the sensors. The dependence of number and location of gas atoms, size of graphene sheets, and type of restrained boundary of the sheets on the sensitivity is particularly studied. The simulation results indicate the resolution of a mass sensor made of a square graphene sheet with a size of 10 nm can achieve an order of 10 femtograms and the mass sensitivity can be enhanced with a decrease in sizes of graphenes.

  4. Vibrations of Elastic Systems With Applications to MEMS and NEMS

    CERN Document Server

    Magrab, Edward B

    2012-01-01

    This work presents a unified approach to the vibrations of elastic systems as applied to MEMS devices, mechanical components, and civil structures. Applications include atomic force microscopes, energy harvesters, and carbon nanotubes and consider such complicating effects as squeeze film damping, viscous fluid loading, in-plane forces, and proof mass interactions with their elastic supports. These effects are analyzed as single degree-of-freedom models and as more realistic elastic structures. The governing equations and boundary conditions for beams, plates, and shells with interior and boundary attachments are derived by applying variational calculus to an expression describing the energy of the system. The advantages of this approach regarding the generation of orthogonal functions and the Rayleigh-Ritz method are demonstrated. A large number of graphs and tables are given to show the impact of various factors on the systems’ natural frequencies, mode shapes, and responses.

  5. Interfacial instabilities in vibrated fluids

    Science.gov (United States)

    Porter, Jeff; Laverón-Simavilla, Ana; Tinao Perez-Miravete, Ignacio; Fernandez Fraile, Jose Javier

    2016-07-01

    Vibrations induce a range of different interfacial phenomena in fluid systems depending on the frequency and orientation of the forcing. With gravity, (large) interfaces are approximately flat and there is a qualitative difference between vertical and horizontal forcing. Sufficient vertical forcing produces subharmonic standing waves (Faraday waves) that extend over the whole interface. Horizontal forcing can excite both localized and extended interfacial phenomena. The vibrating solid boundaries act as wavemakers to excite traveling waves (or sloshing modes at low frequencies) but they also drive evanescent bulk modes whose oscillatory pressure gradient can parametrically excite subharmonic surface waves like cross-waves. Depending on the magnitude of the damping and the aspect ratio of the container, these locally generated surfaces waves may interact in the interior resulting in temporal modulation and other complex dynamics. In the case where the interface separates two fluids of different density in, for example, a rectangular container, the mass transfer due to vertical motion near the endwalls requires a counterflow in the interior region that can lead to a Kelvin-Helmholtz type instability and a ``frozen wave" pattern. In microgravity, the dominance of surface forces favors non-flat equilibrium configurations and the distinction between vertical and horizontal applied forcing can be lost. Hysteresis and multiplicity of solutions are more common, especially in non-wetting systems where disconnected (partial) volumes of fluid can be established. Furthermore, the vibrational field contributes a dynamic pressure term that competes with surface tension to select the (time averaged) shape of the surface. These new (quasi-static) surface configurations, known as vibroequilibria, can differ substantially from the hydrostatic state. There is a tendency for the interface to orient perpendicular to the vibrational axis and, in some cases, a bulge or cavity is induced

  6. The repopulation of electronic states upon vibrational excitation of niobium carbide clusters.

    Science.gov (United States)

    Chernyy, V; Logemann, R; Bakker, J M; Kirilyuk, A

    2016-07-14

    We study the infrared (IR) resonant heating of neutral niobium carbide clusters probed through ultraviolet photoionization spectroscopy. The IR excitation not only changes the photoionization spectra for the photon energies above the ionization threshold, but also modulates ion yield for energies significantly below it. An attempt to describe the experimental spectra using either Fowler's theory or thermally populated vibrational states was not successful. However, the data can be fully modeled by vibrationally and rotationally broadened discrete electronic levels obtained from Density Functional Theory (DFT) calculations. The application of this method to spectra with different IR pulse energies not only yields information about the excited electronic states in the vicinity of the HOMO level, populated by manipulation of the vibrational coordinates of a cluster, but also can serve as an extra indicator for the cluster isomeric structure and corresponding DFT-calculated electronic levels. PMID:27421411

  7. The repopulation of electronic states upon vibrational excitation of niobium carbide clusters.

    Science.gov (United States)

    Chernyy, V; Logemann, R; Bakker, J M; Kirilyuk, A

    2016-07-14

    We study the infrared (IR) resonant heating of neutral niobium carbide clusters probed through ultraviolet photoionization spectroscopy. The IR excitation not only changes the photoionization spectra for the photon energies above the ionization threshold, but also modulates ion yield for energies significantly below it. An attempt to describe the experimental spectra using either Fowler's theory or thermally populated vibrational states was not successful. However, the data can be fully modeled by vibrationally and rotationally broadened discrete electronic levels obtained from Density Functional Theory (DFT) calculations. The application of this method to spectra with different IR pulse energies not only yields information about the excited electronic states in the vicinity of the HOMO level, populated by manipulation of the vibrational coordinates of a cluster, but also can serve as an extra indicator for the cluster isomeric structure and corresponding DFT-calculated electronic levels.

  8. A Non-Uniformly Under-Sampled Blade Tip-Timing Signal Reconstruction Method for Blade Vibration Monitoring

    Directory of Open Access Journals (Sweden)

    Zheng Hu

    2015-01-01

    Full Text Available High-speed blades are often prone to fatigue due to severe blade vibrations. In particular, synchronous vibrations can cause irreversible damages to the blade. Blade tip-timing methods (BTT have become a promising way to monitor blade vibrations. However, synchronous vibrations are unsuitably monitored by uniform BTT sampling. Therefore, non-equally mounted probes have been used, which will result in the non-uniformity of the sampling signal. Since under-sampling is an intrinsic drawback of BTT methods, how to analyze non-uniformly under-sampled BTT signals is a big challenge. In this paper, a novel reconstruction method for non-uniformly under-sampled BTT data is presented. The method is based on the periodically non-uniform sampling theorem. Firstly, a mathematical model of a non-uniform BTT sampling process is built. It can be treated as the sum of certain uniform sample streams. For each stream, an interpolating function is required to prevent aliasing in the reconstructed signal. Secondly, simultaneous equations of all interpolating functions in each sub-band are built and corresponding solutions are ultimately derived to remove unwanted replicas of the original signal caused by the sampling, which may overlay the original signal. In the end, numerical simulations and experiments are carried out to validate the feasibility of the proposed method. The results demonstrate the accuracy of the reconstructed signal depends on the sampling frequency, the blade vibration frequency, the blade vibration bandwidth, the probe static offset and the number of samples. In practice, both types of blade vibration signals can be particularly reconstructed by non-uniform BTT data acquired from only two probes.

  9. [Locator or ball attachment: a guide for clinical decision making].

    Science.gov (United States)

    Büttel, Adrian E; Bühler, Nico M; Marinello, Carlo P

    2009-01-01

    Various attachments are available to retain overdentures on natural roots or implants. Technical aspects, the clinical handling, the capability to adapt or repair and the costs are parameters to be considered when choosing the appropriate attachment. Ball attachments and bars are clinically established and well documented. Ball attachments as prefabricated, unsplinted units are easily replaceable and show hygienic advantages, while bars show favorable stability. The Locator is a newer, popular clinical alternative to these established attachments. The ball attachment and the Locator are compared from a technical and clinical point of view. PMID:19852208

  10. [Locator or ball attachment: a guide for clinical decision making].

    Science.gov (United States)

    Büttel, Adrian E; Bühler, Nico M; Marinello, Carlo P

    2009-01-01

    Various attachments are available to retain overdentures on natural roots or implants. Technical aspects, the clinical handling, the capability to adapt or repair and the costs are parameters to be considered when choosing the appropriate attachment. Ball attachments and bars are clinically established and well documented. Ball attachments as prefabricated, unsplinted units are easily replaceable and show hygienic advantages, while bars show favorable stability. The Locator is a newer, popular clinical alternative to these established attachments. The ball attachment and the Locator are compared from a technical and clinical point of view.

  11. Implications of attachment theory for developmental psychopathology.

    Science.gov (United States)

    Sroufe, L A; Carlson, E A; Levy, A K; Egeland, B

    1999-01-01

    Bowlby's attachment theory is a theory of psychopathology as well as a theory of normal development. It contains clear and specific propositions regarding the role of early experience in developmental psychopathology, the importance of ongoing context, and the nature of the developmental process underlying pathology. In particular, Bowlby argued that adaptation is always the joint product of developmental history and current circumstances (never either alone). Early experience does not cause later pathology in a linear way; yet, it has special significance due to the complex, systemic, transactional nature of development. Prior history is part of current context, playing a role in selection, engagement, and interpretation of subsequent experience and in the use of available environmental supports. Finally, except in very extreme cases, early anxious attachment is not viewed as psychopathology itself or as a direct cause of psychopathology but as an initiator of pathways probabilistically associated with later pathology. PMID:10208353

  12. DFB laser with attached external intensity modulator

    Energy Technology Data Exchange (ETDEWEB)

    Marcuse, D. (AT and T Bell Labs. Holmdel, NJ (US))

    1990-02-01

    This paper presents a theoretical study of the frequency pulling effect exerted on a DFB laser by an external amplitude modulator that is directly attached to it. The modulator consists of a piece of waveguide whose loss is modulated by means of an externally applied voltage. The modulator affects the laser due to residual reflections from its far end which appear as a variable effective reflectivity to the output end of the DFB laser. Modulation affects the magnitude as well as the phase of the effective reflection coefficient presented to the laser due to the coupling of the real and imaginary parts of the effective refractive index of the modulator waveguide. The tuning problem is formulated as an eigenvalue equation for the DFB laser in the presence of an externally attached lossy cavity.

  13. Conflict in close relationships: an attachment perspective.

    Science.gov (United States)

    Simpson, J A; Rholes, W S; Phillips, D

    1996-11-01

    This study investigated how perceptions of current dating partners and relationships change after people with different attachment orientations attempt to resolve a problem in their relationship. Dating couples were videotaped while they tried to resolve either a major or a minor problem. Confirming predictions from attachment theory, men and women who had a more ambivalent orientation perceived their partner and relationship in relatively less positive terms after discussing a major problem. Observer ratings revealed that more ambivalent women who tried to resolve a major problem displayed particularly strong stress and anxiety and engaged in more negative behaviors. Conversely, men with a more avoidant orientation were rated as less warm and supportive, especially if they discussed a major problem. These results are discussed in terms of how highly ambivalent and highly avoidant people differentially perceive and respond to distressing events.

  14. [Set of radiocirculographic attachments for radioisotope laboratories].

    Science.gov (United States)

    Devishev, M I; Panfilova, N P; Ostrogradskaia, M G

    1980-01-01

    A set of radiocirculographic attachments is offered which serves for calibration and verification of readings taken from the apparatus during radiographic procedures. The set is designed for operation with all colimators of radiocirculographs produced in the USSR and Hungarian People's Republic. The set is able to imitate the investigation geometry, accumulation of radioactivity in the organ under study, absorption and scattering of radioactivty in the organism tissues. Series production of this device has already been initiated. PMID:7392870

  15. Preferential attachment in the protein network evolution

    OpenAIRE

    Eisenberg, Eli; Levanon, Erez Y.

    2003-01-01

    The Saccharomyces cerevisiae protein-protein interaction map, as well as many natural and man-made networks, shares the scale-free topology. The preferential attachment model was suggested as a generic network evolution model that yields this universal topology. However, it is not clear that the model assumptions hold for the protein interaction network. Using a cross genome comparison we show that (a) the older a protein, the better connected it is, and (b) The number of interactions a prote...

  16. Attachment of Thiobacillus thiooxidans to sulfur crystals.

    Science.gov (United States)

    SCHAEFFER, W I; HOLBERT, P E; UMBREIT, W W

    1963-01-01

    Schaeffer, W. I. (Rutgers, The State University, New Brunswick, N.J.), P. E. Holbert, and W. W. Umbreit. Attachment of Thiobacillus thiooxidans to sulfur crystals. J. Bacteriol. 85:137-140. 1963.-Electron micrographs of replicas of sulfur crystals before and after attack by Thiobacillus thiooxidans show that the microorganisms erode the crystal in the area immediately adjacent to the cell. When there are many cells, the entire crystal surface appears eroded.

  17. Attachment alternatives in implant-supported overdentures

    OpenAIRE

    Aktaş, Güliz; CANAY, Şenay

    2015-01-01

    Severe resorption of the alveolar ridges often makes it very difficult for patients to wear conventional dentures due to the lack of retention and stability of the dentures. Implant-supported overdentures offer edentulous patients a better retained and more stable prosthesis resulting in improved chewing ability and patient satisfaction compared against conventional complete dentures. There exist various attachment systems to be used with overdenture prostheses and are available in the market...

  18. Probing the Solar System

    Science.gov (United States)

    Wilkinson, John

    2013-01-01

    Humans have always had the vision to one day live on other planets. This vision existed even before the first person was put into orbit. Since the early space missions of putting humans into orbit around Earth, many advances have been made in space technology. We have now sent many space probes deep into the Solar system to explore the planets and…

  19. One-Probe Search

    DEFF Research Database (Denmark)

    Östlin, Anna; Pagh, Rasmus

    2002-01-01

    We consider dictionaries that perform lookups by probing a single word of memory, knowing only the size of the data structure. We describe a randomized dictionary where a lookup returns the correct answer with probability 1 - e, and otherwise returns don't know. The lookup procedure uses an expan...

  20. Analyzing intramolecular vibrational energy redistribution via the overlap intensity-level velocity correlator

    OpenAIRE

    Keshavamurthy, Srihari; Cerruti, Nicholas R.; Tomsovic, Steven

    2002-01-01

    Numerous experimental and theoretical studies have established that intramolecular vibrational energy redistribution (IVR) in isolated molecules has a heirarchical tier structure. The tier structure implies strong correlations between the energy level motions of a quantum system and its intensity-weighted spectrum. A measure, which explicitly accounts for this correaltion, was first introduced by one of us as a sensitive probe of phase space localization. It correlates eigenlevel velocities w...