Development and application of techniques for the acquisition of ultra-wideline solid-state NMR spectra

Wideline and ultra-wideline (UW) (i.e., \u3e 250 kHz broad) solid-state NMR (SSNMR) spectra are acquired for a wide variety of nuclei (i.e., 119Sn, 195Pt, 199Hg, 207Pb, 27Al, 71Ga) using multiple acquisition techniques. The WURST-CPMG pulse sequence is shown to acquire such patterns efficiently and without the need for piecewise acquisition. Preliminary investigations into the use of optimal control theory (OCT) are also carried out, and show promise for future studies. Additionally, a series of Pb(II) thiolate species, which exhibit unique Pb bonding environments, are characterized with 207Pb SSNMR. Density Functional Theory (DFT) calculations are performed to determine chemical shielding (CS) tensor orientations within the molecular frame, which are then correlated to the experimental spectra. Finally, several group 13 guanidinates (guan = MeN-C(N iPr2)-NMe) are studied via 27Al and 71Ga SSNMR at 9.4 T and 21.1 T, and experimental data is complemented with ab initio calculations, and the CS and electric field gradient tensor parameters are found to have a great dependence on metal coordination number and the nature of the metal-ligand bond

Telecommunications and radio-metric support for a manned mission to Mars

Some general characteristics of the Deep Space Network are described and related to services needed by a manned mission to Mars. Specific details of the current Network capabilities and those planned for the near future may be found in the reference

A political history of the Macgregors before 1571.

SIGLEAvailable from British Library Document Supply Centre- DSC:D89256 / BLDSC - British Library Document Supply CentreGBUnited Kingdo

Effects of Cyclic Loading on Mechanical Behavior of 24S-T4 and 75S-T6 Aluminum Alloys and SAE 4130 Steel

An investigation was conducted to determine the effects of cyclic loading on the mechanical behavior of 24S-T4 and 75S-T6 aluminum alloys and SAE 4130 steel. Specimens of the three materials were subjected to various numbers of prior fatigue cycles both below and above the fatigue limits. Special slow-bend tests were employed to show the effects of prior cycles of fatigue stressing on the transition temperature to brittle fracture for SAE 4130 steel and on the energy-absorption capacity of the aluminum alloys. Micrographic studies were made to observe and measure crack formation and propagation and additional special tests were conducted to supplement the results of the slow-bend tests. These included Charpy impact tests, mirohardness surveys, tension tests, and fretting-corrosion studies

Fabrication and properties of gallium phosphide variable colour displays

The unique properties of single-junction gallium phosphide devices incorporating both red and green radiative recombination centers were investigated in application to the fabrication of monolithic 5 x 7 displays capable of displaying symbolic and alphanumeric information in a multicolor format. A number of potentially suitable material preparation techniques were evaluated in terms of both material properties and device performance. Optimum results were obtained for double liquid-phase-epitaxial process in which an open-tube dipping technique was used for n-layer growth and a sealed tipping procedure for subsequent p-layer growth. It was demonstrated that to prepare devices exhibiting a satisfactory range of dominant wavelengths which can be perceived as distinct emission colors extending from the red through green region of the visible spectrum involves a compromise between the material properties necessary for efficient red emission and those considered optimum for efficient green emission

Preferences of children in grades two through eight in social studies subject areas

Thesis (Ed.M.)--Boston Universit

Sequence Characterization of Extra-Chromosomal Circular DNA Content in Multiple Blackgrass (Alopecurus myosuroides) Populations.

Alopecurus myosuroides (blackgrass) is a problematic weed of Western European winter wheat, and its success is largely due to widespread multiple-herbicide resistance. Previous analysis of F2 seed families derived from two distinct blackgrass populations exhibiting equivalent non-target site resistance (NTSR) phenotypes shows resistance is polygenic and evolves from standing genetic variation. Using a CIDER-seq pipeline, we show that herbicide-resistant (HR) and herbicide-sensitive (HS) F3 plants from these F2 seed families as well as the parent populations they were derived from carry extra-chromosomal circular DNA (eccDNA). We identify the similarities and differences in the coding structures within and between resistant and sensitive populations. Although the numbers and size of detected eccDNAs varied between the populations, comparisons between the HR and HS blackgrass populations identified shared and unique coding content, predicted genes, and functional protein domains. These include genes related to herbicide detoxification such as Cytochrome P450s, ATP-binding cassette transporters, and glutathione transferases including AmGSTF1. eccDNA content was mapped to the A. myosuroides reference genome, revealing genomic regions at the distal end of chromosome 5 and the near center of chromosomes 1 and 7 as regions with a high number of mapped eccDNA gene density. Mapping to 15 known herbicide-resistant QTL regions showed that the eccDNA coding sequences matched twelve, with four QTL matching HS coding sequences; only one region contained HR coding sequences. These findings establish that, like other pernicious weeds, blackgrass has eccDNAs that contain homologs of chromosomal genes, and these may contribute genetic heterogeneity and evolutionary innovation to rapidly adapt to abiotic stresses, including herbicide treatment

Pre-Determining Performance-Based Measures for Managed Lanes

The operational decisions facing managed lanes can be highly politicized and difficult to make quickly. For example, changing the operating parameters such that a user class can no longer access the lanes may require extensive public debate and ignite controversy. This research examined managed lanes across the country and found that none had developed plans on how to deal with such situations as they arise in the future. We found there are significant potential benefits for agencies if they use operational goals for their managed lane facilities to guide decision making prior to the point it becomes critical. In addition, the policies developed act as a performance promise to managed lane users