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Displaying 13151 - 13175 of 74220

Wind Effects on Tall Buildings: A Database-Assisted Design Approach

February 19, 2017
Author(s)
William P. Fritz, Emil Simiu
A rigorous procedure that calculates wind-induced effects on tall buildings is presented. The method, an extension of Database-Assisted Design (DAD), uses sets of time histories of pressures recorded simultaneously in the wind tunnel at a large number of

Wind Load Factors for Tall Building Design and the ASCE 7 Standard

February 19, 2017
Author(s)
Rene D. Gabbai, Emil Simiu
Wind load factors incorporated in the ASCE 7 Standard are based on rough approximations of wind effects and the uncertainties inherent in them. These factors are routinely applied to tall building design, even though the original calculations on which they

Wind Speeds for the Estimation of World Trade Center Towers' Response

February 19, 2017
Author(s)
William P. Fritz, Fahim H. Sadek, Emil Simiu
Estimates of the World Trade Center (WTC) towers response to wind by two North American wind engineering laboratories differed from each other by almost 40 %. A recent investigation by the National Institute of Standards and Technology determined that

Workshop on Purity and Dispersion Measurement Issues of Single Wall Carbon Nanotubes (SWCNTs)

February 19, 2017
Author(s)
Stephen W. Freiman, Richard R. Cavanagh, C K. Montgomery, Thomas J. Shaffner, S Arepalli, B Files, P Nikolaev
This document is an executive summary of a workshop organized jointly by the National Aeronautics and Space Administration, Lyndon B. Johnson Space Center (NASA/JSC) and the National Institute of Standards and Technology (NIST) was held on May 27-29, 2003

X-Ray Absorption Fine-Structure Determination of Ferroelectric Distortion in SrtiO 3 Thin Films grown on Si(001)

February 19, 2017
Author(s)
Joseph Woicik, F S. Aguirre-Tostado, A Herrera-Gomez, R Droopad, Z Yu, D G. Schlom, E Karapetrova, P Zschack, P Pianetta
Polarization-dependent x-ray absorption fine structure together with x-ray diffraction have been used to study the local structure in SrTiO 3 thin films grown on Si(001). Our data indicate that below a critical thickness of approximately 80 , the in-plane

Ba 8 CoNb 6 O 24 : A Spin-1/2 Triangular-Lattice Heisenberg Antiferromagnet in the Two-Dimensional Limit

February 17, 2017
Author(s)
R. Rawl, L. Ge, H. Agrawal, Y. Kamiya, C. R. Dela Cruz, Nicholas Butch, X. F. Sun, M. Lee, E. S. Choi, J. Oitmaa, C. D. Batista, M. Mourigal, H. D. Zhou, J. Ma
The quasi-two-dimensional perovskite Ba 8CoNb 6O 24 comprises equilateral effective spin-1/2 Co 2+ triangular layers separated by six nonmagnetic Nb 5+ layers. Susceptibility, specific heat and neutron scattering measurements combined with high-temperature

Direct measurement of Vorticella contraction force by micropipette deflection

February 17, 2017
Author(s)
Danielle C. France, Jonathan Tejada, Paul Matsudaira
The ciliated protozoan Vorticella convallaria is noted for its exceptionally fast ATP-independent cellular contraction, but direct measurements of contractile force have proven difficult given the length scale, speed, and forces involved. We used high

Field Programmable Josephson Amplifier for non-reciprocal microwave signal processing

February 17, 2017
Author(s)
Florent Q. Lecocq, Leonardo Ranzani, Gabriel A. Peterson, Katarina Cicak, Raymond W. Simmonds, John D. Teufel, Jose A. Aumentado
We report on the design and implementation of a Field Programmable Josephson Amplifier (FPJA) - a compact and lossless superconducting circuit that can be programmed in-situ by a set of microwave drives to perform reciprocal and non-reciprocal frequency

Limited options for low-global-warming-potential refrigerants

February 17, 2017
Author(s)
Mark O. McLinden, J S. Brown, Riccardo Brignoli, Andrei F. Kazakov, Piotr A. Domanski
Hydrofluorocarbons, currently used as refrigerants in air-conditioning systems, are potent greenhouse gases, and their contribution to climate change is projected to increase. Future use of the hydrofluorocarbons will be phased down and, thus, replacement

Partial breakdown of quantum thermalization in a Hubbard-like model

February 17, 2017
Author(s)
James R. Garrison, Ryan Mishmash, Matthew P. Fisher
We study the possible breakdown of quantum thermalization in a model of itinerant electrons on a one-dimensional chain without disorder, with both spin and charge degrees of freedom. The eigenstates of this model exhibit peculiar properties in the

Revised analysis of the fifth spectrum of rhenium (Re V)

February 17, 2017
Author(s)
Vladimir I. Azarov, R R. Gayasov
The spectrum of rhenium was observed in the (500 to 2100) A wavelength region. A 6.65 m normal incidence VUV spectrograph has been used to record the spectrum. The (5d3 + 5d26s) - 5d26p transition array of four times ionized rhenium, Re V, has been

Self-contained, Low Cost “Body-on-a-Chip” Systems for Drug Development

February 17, 2017
Author(s)
Ying Wang, Oleaga Carlota, Long Christopher, McAleer Christopher, Paula Miller, James J. Hickman, Michael L. Shuler, Mandy B. Esch
Integrated multi-organ microphysiological systems are an evolving tool for preclinical evaluation of the potential toxicity and efficacy of drug candidates. Such systems, also known as “Body-on-a-Chip” devices, have a great potential to increase the

Ultrafast time-resolved x-ray absorption spectroscopy of ferrioxalate photolysis with a laser plasma x-ray source and microcalorimeter array

February 17, 2017
Author(s)
Galen C. O'Neil, Joel N. Ullom, Luis Miaja Avila, Young Il Joe, Joseph W. Fowler, Carl D. Reintsema, Daniel S. Swetz, Kevin L. Silverman, Daniel R. Schmidt, Bruce D. Ravel, Gene C. Hilton, William B. Doriese, Bradley K. Alpert, Ralph Jimenez
Using a table-top apparatus based upon a laser plasma x-ray source and an array of cryogenic microcalorimeter x-ray detectors, we have measured the transient x-ray absorption spectrum during the ferrioxalate photoreduction reaction. We observe the Fe K

Uniaxial Pressure Effect on the Magnetic Ordered Moment and Transition Temperatures in BaFe 2-x T x As 2 (T=Co,Ni)

February 17, 2017
Author(s)
David W. Tam, Yu Song, Haoran Man, Sky C. Cheung, Zhiping Yin, Xingye Lu, Weiyi Wang, Benjamin A. Frandsen, Lian Liu, Zizhou Gong, Takashi U. Ito, Yipeng Cai, Murray N. Wilson, Shengli Guo, Keisuke Koshiishi, Wei Tian, Bassam Hitti, Alexandre Ivanov, Yang Zhao, Jeffrey W. Lynn, Graeme M. Luke, Tom Berlijn, Thomas A. Maier, Yasutomo J. Uemura, Pengcheng Dai
We use neutron diffraction and muon spin relaxation to study the effect of uniaxial pressure on the paramagnetic-to-antiferromagnetic phase transition (T N) in BaFe 2As 2 and superconducting BaFe 1.915Ni 0.085As 2. In a local moment picture, the uniaxial

Email Authentication Mechanisms: DMARC, SPF and DKIM

February 16, 2017
Author(s)
J. S. Nightingale
In recent years the IETF has been making a range of efforts to secure the email infrastructure and its use. Infrastructure protection includes source authentication by RFC 7208 Sender Policy Framework (SPF), message integrity authentication by RFC 6376

Repair of Oxidatively Induced DNA Damage by DNA Glycosylases

February 16, 2017
Author(s)
M Miral Dizdar, Erdem Coskun, Pawel Jaruga
Endogenous and exogenous reactive species cause oxidatively induced DNA damage in living organisms by a variety of mechanisms. As a result, a plethora of mutagenic and/or cytotoxic products are formed in cellular DNA. This type of DNA damage is repaired by
Displaying 13151 - 13175 of 74220