U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications by: Dean C Ripple (Fed)

Search Title, Abstract, Conference, Citation, Keyword or Author
Displaying 26 - 50 of 80

The Metrology of Counting Protein Particles

July 13, 2013
Author(s)
Dean C. Ripple, Michael J. Carrier, Richard E. Cavicchi, Christopher B. Montgomery, Zhishang Hu
A common degradation pathway for protein-based drugs is the growth of protein aggregates or particles. Counting and characterization of these particles is needed to assure the quality, efficacy, and safety of this type of drug. The unusual physical

The Metrology of Counting Protein Particles

March 18, 2013
Author(s)
Dean C. Ripple, Michael J. Carrier, Richard E. Cavicchi, Christopher B. Montgomery, Zhishang Hu
A common degradation pathway for protein-based drugs is the growth of protein aggregates or particles. Counting and characterization of these particles is needed to assure the quality, efficacy, and safety of this type of drug. The unusual physical

Uncertainty Budget for the NIST Hybrid Humidity Generator

December 1, 2012
Author(s)
Christopher W. Meyer, W Wyatt Miller, Dean C. Ripple, Gregory E. Scace
We provide here a detailed uncertainty budget for the new Hybrid Humidity Generator (HHG) that has been constructed at the National Institute of Standards and Technology (NIST). The HHG generates frost/dew points from –70 °C to +85 °C using calibration gas

A Humidity Generator for Temperatures to 200 degC and Pressures to 1.6 MPa

November 30, 2012
Author(s)
D Vega-Maza, W. Wyatt Miller, Dean C. Ripple, Gregory E. Scace
We have constructed a new humidity generator that produces gas streams of known moisture content at temperatures from 85 °C to 200 °C, absolute pressures from 0.2 MPa to 1.6 MPa, and relative humidities from 10 % to 90 %. The generator produces a moist gas

Room Temperature Acoustic Transducers for High-Temperature Thermometry

July 9, 2012
Author(s)
Dean C. Ripple, William E. Murdock, Gregory F. Strouse, Keith A. Gillis, Michael R. Moldover
We have successfully conducted highly-accurate, primary acoustic thermometry at 600 K using a sound source and a sound detector at room temperature. We describe the source, the detector, and the ducts that connected them to our cavity resonator. This

Protein Particles: What We Know and What We Don’t Know

June 26, 2012
Author(s)
Dean C. Ripple, Mariana Dimitrova
All therapeutic protein products contain particles formed by the aggregation of protein monomers. There is a growing interest in the understanding of particles in biopharmaceutical products, which has been fostered on the one hand by significant

Standards for the Optical Detection of Protein Particulates

January 23, 2012
Author(s)
Dean C. Ripple, Michael J. Carrier, Joshua R. Wayment
Particulates in protein therapeutics, composed of agglomerated protein monomers, may cause an immunogenic response in patients. Consequently, industry and the FDA desire more accurate methods for counting and characterizing particulates. Unlike likely

The Residual Resistance Ratio of High-Purity Platinum

August 22, 2011
Author(s)
Weston L. Tew, William E. Murdock, Michal J. Chojnacky, Dean C. Ripple
High-purity platinum wire is produced for use in both Standard Platinum Resistance Thermometers (SPRTs) and type S and type R thermocouples. The resistance ratio W(T90) and thermoelectric characteristics of the wire are a function of chemical purity and

The Roles of the Mise en Pratique for the Definition of the Kelvin

October 16, 2010
Author(s)
Dean C. Ripple, Richard Davis, Bernd Fellmuth, Joachim Fischer, Graham Machin, Terry Quinn, Peter Steur, Osamu Tamura, David R. White
The mise en pratique (“practical realization”) for the definition of the kelvin (MeP-K) was created by the Consultative Committee for Thermometry (CCT) in 2006 to give practitioners of thermometry a guide to the realization of the kelvin, in accord with

Characterization of gold nanoparticles modified with single-stranded DNA using analytical ultracentrifugation and dynamic light scattering

August 3, 2010
Author(s)
James Falabella, Tae Joon Cho, Dean C. Ripple, Vincent A. Hackley, Michael J. Tarlov
We report the characterization of gold nanoparticles modified with thiol-terminated single stranded DNA using analytical ultracentrifugation and dynamic light scattering. Sedimentation coefficients of nominally 10 and 20 nm diameter gold nanoparticles

Thermal Analysis of Refrigeration Systems Used for Vaccine Storage

November 2, 2009
Author(s)
Michal J. Chojnacky, W Wyatt Miller, Dean C. Ripple, Gregory F. Strouse
Each year, billions of dollars of vaccines are stored in refrigerators at the facilities of a variety of medical providers. Many vaccines must be maintained in the range 2 °C to 8 °C to retain product potency. We have tested the performance of two types of

Thermometry Issues in Destruction Kinetics Measurements

June 26, 2009
Author(s)
Dean C. Ripple
Of all the aspects of destruction kinetics measurement, the one taken most for granted is temperature measurement. The ubiquity of digital thermometers and their ease of use have disguised potential accuracy issues in the range of temperature encountered

Design and Performance of the New NIST Hybrid Humidity Generator

June 1, 2009
Author(s)
Christopher W. Meyer, W Wyatt Miller, Dean C. Ripple, Gregory E. Scace
A new humidity generator has been constructed at the National Institute of Standards and Technology and is now fully operational. The NIST Hybrid Humidity Generator (HHG) has replaced the Two-Pressure (2-P) Humidity Generator Mark II as the NIST primary

Thin-Film Resistance Thermometers on Silicon Wafers

March 3, 2009
Author(s)
Kenneth G. Kreider, Dean C. Ripple, William A. Kimes
Thermal processing of semiconductors is a critical, capital intensive step in achieving high yields and profitability in the manufacturing of electronic chips such as ASICs and DRAMs. Many techniques have been developed to control the temperature of the

Maintenance and Validation of Liquid-in-Glass Thermometers

January 1, 2009
Author(s)
Christina D. Cross, Dean C. Ripple, Gregory F. Strouse
Liquid-in-glass thermometers are pervasive in use throughout industry and provide a convenient method for measuring temperature over for a broad range of applications with reasonable stability and accuracy. However, liquid-in-glass thermometers are subject

Calibration of Hygrometers with the Hybrid Humidity Generator

December 14, 2008
Author(s)
Christopher W. Meyer, Joseph T. Hodges, Peter H. Huang, W Wyatt Miller, Dean C. Ripple, Gregory E. Scace
We describe here the calibration of customer hygrometers using a new humidity generator that has been commissioned at the National Institute of Standards and Technology. The NIST Hybrid Humidity Generator (HHG) generates frost/dew points from –70 °C to +85

Cold Chain Storage of Vaccines: A Brief Introduction to Thermometry

September 1, 2008
Author(s)
Dean C. Ripple
To maintain the efficacy of vaccines requires maintaining the storage temperature within well-defined limits; vaccine failure due to improper storage results in large direct and indirect public health costs. In this presentation, I give a brief

Recommended List of Common Impurities for Metallic Fixed-point Materials of the ITS-90

August 18, 2008
Author(s)
Dean C. Ripple, Anatoly Pokhodun, Peter Steur, Gregory F. Strouse
Working Group 1 of the Consultative Committee for Thermometry (CCT) has recommended methods for estimating the uncertainties of fixed-point temperatures attributable to chemical impurities [1]. These methods require chemical analysis of all commonly found

Report from the Mise en Pratique Task Group: the next international temperature scale and the mise en pratique for the definition of the kelvin

August 18, 2008
Author(s)
Dean C. Ripple, Bernd Fellmuth, Joachim Fischer, Graham Machin, PPM Steur, Osamu Tamura, Rod D. White
The Consultative Committee for Thermometry has asked Working Group 1 to coordinate a task group formulating an assessment and possible work plan for the next International Temperature Scale and to prepare and maintain the mise en pratique for the

Design and Performance of the new NIST Hybrid Humidity Generator

August 1, 2008
Author(s)
Christopher W. Meyer, W Wyatt Miller, Dean C. Ripple, Gregory E. Scace
A new humidity generator has been constructed at the National Institute of Standards and Technology. Once fully operational, the NIST Hybrid Humidity Generator (HHG) will replace the Two-Pressure (2-P) Humidity Generator Mark II as the NIST primary

A Regional Comparison of Calibration Results for Type K Thermocouple Wire From 100 C to 1100 C

June 5, 2008
Author(s)
K Garrity, Dean C. Ripple, M Araya, C R. Cabrera, L Cordova Murillo, M E. de Vanegas, D J. Gee, Edwin Guillen, S Martinez-Martinez, Edgar Mendez-Lango, L Mussio, S G. Petkovic, K N. Quelhas, G Rangugni, O Robatto, E Von Borrries Rocha
Under the auspices of the Inter-american Metrology System (SIM), the National Institute of Standards and Technology (NIST) initiated a regional comparison for type K thermocouples from 100 deg. C to 1100 deg. C, with 11 participating countries. Each

Acoustic Thermometry Results From 271 K to 552 K

September 8, 2007
Author(s)
Dean C. Ripple, Gregory F. Strouse, Michael R. Moldover
The NIST Acoustic Thermometer determines the thermodynamic temperature from measurements of ratios of the speed of sound of argon in a spherical cavity. We report recent results for T - T90 on 12 isotherms spanning the range 271 K to 552 K. (T is the

Critical Frequency Estimates for Thermowells

March 21, 2007
Author(s)
David Bartran, Dean C. Ripple
The ASME Performance Test Code, PTC 19.3, establishes the service ratings of thermowells in terms of static pressure limitations and susceptibility of the thermowell to flow-induced resonance. It relies on a simplified method to establish the resonant

Determination of SPRT Realization Uncertainties Between Points

September 6, 2006
Author(s)
Christopher W. Meyer, Dean C. Ripple
Calibrated Standard Platinum Resistance Thermometers (SPRTs) are used to realize the International Temperature Scale of 1990 (ITS-90) from 13.8033 K to 1234.93 K. The SPRTs are calibrated at a series of fixed points, each assigned a temperature on the ITS