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NIST Authors in Bold

Displaying 22851 - 22875 of 73697

Synthesis and characterization of model crosslinked polyamide films for water purification

June 24, 2012
Author(s)
Peter M. Johnson, Edwin Chan, Jun Y. Chung, Junghyun Lee, Christopher Stafford
Reverse osmosis (RO) and nanofiltration (NF) membranes are comprised of a dense active layer supported by a porous support. Commercial active layer are highly crosslinked polyamides that are formed through interfacial polymerization directly on the support

Metal-Assisted Hydrogen Storage on Pt-Decorated Single-Walled Carbon Nanohorns

June 23, 2012
Author(s)
Yun Liu, Craig M. Brown, Dan A. Neumann, David B. Geohegan, Alexander A. Puretzky, Christopher M. Rouleau, Hui Hu, David Styers-Barnett, Pavel O. Krasnov, Boris I. Yakobson
Current methods to study the spillover effect in hydrogen storage materials typically must compare the results from a separate reference sample. This makes it difficult to determine with confidence the amount of adsorbed hydrogen only associated with

13C - NMR Absorptions of Major Functional Groups

June 22, 2012
Author(s)
Thomas J. Bruno, Paris D. Svoronos
The table below lists the 13C chemical shift ranges (in ppm) with the corresponding functional groups in descending order. A number of typical simple compounds for every family are given to illustrate the corresponding range. The shifts for the carbons of

15 N - NMR Chemical Shifts of Major Chemical Families

June 22, 2012
Author(s)
Thomas J. Bruno, Paris D. Svoronos
The following table contains 15N NMR chemical shifts of various organic nitrogen compounds. Chemical shifts are expressed relative to different standards (NH 3, NH 4Cl, CH 3NO 2, NH 4NO 3, HNO 3, etc.) and are interconvertible. Chemical shifts are

Analytical Standardization and Calibration

June 22, 2012
Author(s)
Thomas J. Bruno
Most modern instrumental techniques used in analytical chemistry produce an output or signal that is not absolute; the signal or peak is not a direct quantitative measure of concentration or target analyte quantity. Thus, to perform quantitative analysis

Atomic Masses and Abundances

June 22, 2012
Author(s)
Thomas J. Bruno, Paris D. Svoronos
The following table lists the atomic masses and relative percent concentrations of naturally occurring isotopes of importance in mass spectroscopy.

Common Mass Spectral Fragmentation Patterns of Organic Compound Families

June 22, 2012
Author(s)
Thomas J. Bruno, Paris D. Svoronos
The following table provides a guide to the identification and interpretation of commonly observed mass spectral fragmentation patterns for common organic functional groups [1-10]. It is of course highly desirable to augment mass spectroscopic data with as

Common Mass Spectral Fragments Lost

June 22, 2012
Author(s)
Thomas J. Bruno, Paris D. Svoronos
The following table gives a list of neutral species that are most commonly lost when measuring the mass spectra of organic compounds. The list is suggestive rather than comprehensive, and should be used in conjunction with other sources [1-5]. The listed

Common Spurious Infrared Absorption Bands

June 22, 2012
Author(s)
Thomas J. Bruno, Paris D. Svoronos
The following table provides some of the common potential sources of spurious infrared absorptions that might appear on a spectrum.

Common Spurious Signals Observed in Mass Spectrometers

June 22, 2012
Author(s)
Thomas J. Bruno, Paris D. Svoronos
The following table provides guidance in the recognition and interpretation of spurious signals (m/z peaks) that will sometimes be observed in measured mass spectra [1]. Often, the occurrence of these signals can be predicted by the recent history of the

Common Spurious Signals Observed in Mass Spectrometers

June 22, 2012
Author(s)
Thomas J. Bruno, Paris D. Svoronos
The following table provides guidance in the recognition of spurious signals (m/z peaks) that will sometimes be observed in measured mass spectra, especially when the mass spectrometer is interfaced to a gas chromatograph [1]. Often, the occurrence of

Detection of outliers in measurements

June 22, 2012
Author(s)
Thomas J. Bruno, Paris D. Svoronos
The field of outlier detection and treatment is considerable, and a rigorous mathematical discussion is well beyond any treatment that is possible here. Moreover, the practice in the treatment of analytical results is usually simplified, since the number

Detectors for Gas Chromatography

June 22, 2012
Author(s)
Thomas J. Bruno, Paris D. Svoronos
The following table provides some comparative data for the selection and operation of the more common detectors applied to capillary and packed column gas chromatography [1-8]. For more detailed information regarding operation and interpretation of results

Electro-Mechanical Properties of Graphene Drumheads

June 22, 2012
Author(s)
Nikolai N. Klimov, Suyong S. Jung, Shuze Zhu, Teng Li, C. Alan Wright, Santiago Solares, David B. Newell, Nikolai B. Zhitenev, Joseph A. Stroscio
The electro-mechanical properties of a suspended graphene layer are determined by scanning tunneling microscopy (STM) and spectroscopy (STS) measurements and computational simulations of the graphene membrane mechanics and morphology. The graphene membrane

Eluotropic Values of Solvents on Octadecylsilane and Octylsilane

June 22, 2012
Author(s)
Thomas J. Bruno, Paris D. Svoronos
The following table provides, for comparative purposes, eluotropic values on bonded octadecyl silane (ODS) and octyl silane (OS) for common solvents.[1-3] For additional information on common, specific and chiral stationary phases for HPLC, and for

Indicators for Acids and Bases

June 22, 2012
Author(s)
Thomas J. Bruno, Paris D. Svoronos
The following table lists the most common indicators together with their pH range and colors in acidic and basic media. Since the color change is not instantaneous at the pKa value, a pH range is given where a combination of colors is present. This pH

Middle-Range Infrared Absorption Correlation Charts

June 22, 2012
Author(s)
Thomas J. Bruno, Paris D. Svoronos
The following charts provide characteristic middle range infrared absorptions obtained from particular functional groups on molecules [1,2]. These include a general mid-range correlation chart, a chart for aromatic absorptions, and a chart for carbonyl

Organic Analytical Reagents for the Determination of Inorganic Cations

June 22, 2012
Author(s)
Thomas J. Bruno, Paris D. Svoronos
The table entitled Organic Analytical Reagents for the Determination of Inorganic Substances, by G. Ackermann, L. Sommer, and D. Thorburn Burns, has been revamped and considerably expanded for this edition. The many recent advancements in this area have

Photo-induced Surface Transformation of Silica Nanocomposites

June 22, 2012
Author(s)
Justin M. Gorham, Tinh Nguyen, Coralie Bernard, Deborah S. Jacobs, Richard D. Holbrook
The physicochemical, UV-induced surface modifications to silica nanoparticle (SiNP) - epoxy composites have been investigated. The silica nanocomposites (SiNCs) were prepared using a two-part epoxy system with 10 % mass fraction of SiNPs and exposed to

Preparation of Special Analytical Reagents

June 22, 2012
Author(s)
Thomas J. Bruno, Paris D. Svoronos
This listing of analytical reagents has been updated to include formulations based on more recent experience, and also safety notes. In the absence of specific cautions, the user must observe sound laboratory practice and housekeeping to avoid exposure and

Properties of Common Cross-Linked Silicone Stationary Phases

June 22, 2012
Author(s)
Thomas J. Bruno, Paris D. Svoronos
Modern gas chromatography is most often performed with high efficiency capillary (open tubular) columns coated with a cross linked polymeric stationary phase. We provide chromatographic data on the two most common cross-linked phases [1]. The retention

Properties of Important NMR Nuclei

June 22, 2012
Author(s)
Thomas J. Bruno, Paris D. Svoronos
The following table lists the magnetic properties at higher field strengths required for choosing the nuclei to be used in NMR experiments [1-15]. The reader is referred to several excellent texts and the literature for guidelines in nucleus selection. For

Proton NMR Absorption of Major Chemical Families

June 22, 2012
Author(s)
Thomas J. Bruno, Paris D. Svoronos
The following table gives the region of the expected nuclear magnetic resonance absorptions of hydrocarbon families. These absorptions are reported in the dimensionless units of parts per million (ppm) versus the standard compound tetramethylsilane (TMS
Displaying 22851 - 22875 of 73697
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