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The Butterfly Dimer [(tBu3SiO)Cr]2 (μ-OSitBu3)2 and Its Oxidative Cleavage to (tBu3SiO)2 Cr(=N-N=CPh2)2 and (tBu3SiO)2 Cr=N(2,6-Ph2-C6H3)

Description: Article discussing research on the butterfly dimer [(ᵗBu₃SiO)Cr]₂(μ-OSiᵗBu₃)₂ and its oxidative cleavage to (ᵗBu₃SiO)₂Cr(=N-N=CPh₂)₂ and (ᵗBu₃SiO)₂Cr=N(2,6-Ph₂-C₆H₃).
Date: January 12, 2006
Creator: Sydora, Orson L.; Kuiper, David S.; Wolczanski, Peter T.; Lobkovsky, Emil B.; Dinescu, Adriana & Cundari, Thomas R., 1964-
Partner: UNT College of Arts and Sciences

The Dual Role of Oxygen Functions in Coal Pretreatment and Liquefaction: Crosslinking and Cleavage Reactions

Description: The overall objective of this project was to elucidate and model the dual role of oxygen functions in thermal pretreatment and liquefaction of low rank coals through the application of analytical techniques and theoretical models. The project was an integrated study of model polymers representative of coal structures, raw coals of primarily low rank, and selectively modified coals in order to provide specific information relevant to the reactions of real coals. The investigations included liquefaction experiments in microautoclave reactors, along with extensive analysis of intermediate solid, liquid and gaseous products. Attempts were made to incorporate the results of experiments on the different systems into a liquefaction model.
Date: September 30, 1993
Creator: Serio, Michael; Kroo, Erik; Charpenay, Sylvie & Solomon, Peter
Partner: UNT Libraries Government Documents Department

Chemical Cleavage of Human Phosphoglucose Isomerase at Cysteine

Description: The present study has resulted in the development of a procedure for the specific chemical fragmentation of human phosphoglucose isomerase into a minimal number of peptides. A two-cycle procedure for cleaving the protein with 2-nitro-5- thiocyanobenzoic acid results in four primary peptides and three overlap peptides. The peptides can be readily separated on the basis of their size by using sodium dodecyl sulfate polyacrylamide gel electrophoresis. Preliminary peptide alignments have been considered, and amino acid analyses have been performed. End-terminal analyses of the enzyme revealed a carboxyl terminal sequence of Asp-Val-Gln and a blocked amino terminus. The cysteine cleavage procedure provides an excellent method for the identification and location of specific genetic mutations of human phosphoglucose isomerase.
Date: December 1975
Creator: Conn, Worth R.
Partner: UNT Libraries

Observation of Cleavage Fracture after Substantial Dimple Rupture in ASTM A710 Steel

Description: A major concern often arising in structural integrity predictions is the possibility that low-energy brittle fracture could result as a consequence of cleavage either under normal operating or design accident conditions. This can be especially troublesome when the leak-before-break (LBB) approach shows an additional safety margin of the design. For LBB to be applicable, the fracture process must remain ductile (dimple rupture), and not change to cleavage. The American Society for Mechanical Engineers Boiler and Pressure Vessel Code (Code) provides guidelines for avoiding cleavage fracture for Code-accepted materials. Experimental results for a non-Code steel are provided, and show that cleavage may occur for a thickness under16 mm (where the code suggests it will not) after stable crack growth (∆a) of up to 20 mm. This work is still in progress; test results are provided along with possible reasons for the mode transition, but complete explanations are still being developed.
Date: July 1, 2000
Creator: Reuter, Walter Graham & Lloyd, Wilson Randolph
Partner: UNT Libraries Government Documents Department

Coordinateendonucleolytic 5' and 3' trimming of terminally blocked blunt DNA double-strand break ends by Artemis nuclease and DNA-dependent protein kinase

Description: Previous work showed that, in the presence of DNA-PK, Artemis slowly trims 3'-phosphoglycolate-terminated blunt ends. To examine the trimming reaction in more detail, long internally labeled DNA substrates were treated with Artemis. In the absence of DNA-PK, Artemis catalyzed extensive 5' {yields} 3' exonucleolytic resection of double-stranded DNA. This resection required a 5'-phosphate but did not require ATP, and was accompanied by endonucleolytic cleavage of the resulting 3' overhang. In the presence of DNA-PK, Artemis-mediated trimming was more limited, was ATP-dependent, and did not require a 5'-phosphate. For a blunt end with either a 3'-phosphoglycolate or 3'-hydroxyl terminus, endonucleolytic trimming of 2-4 nucleotides from the 3'-terminal strand was accompanied by trimming of 6 nucleotides from the 5'-terminal strand. The results suggest that autophosphorylated DNA-PK suppresses the exonuclease activity of Artemis toward blunt-ended DNA, and promotes slow and limited endonucleolytic trimming of the 5'-terminal strand, resulting in short 3' overhangs that are trimmed endonucleolytically. Thus, Artemis and DNA-PK can convert terminally blocked DNA ends of diverse geometry and chemical structure to a form suitable for polymerase mediated patching and ligation, with minimal loss of terminal sequence. Such processing could account for the very small deletions often found at DNA double-strand break repair sites.
Date: February 18, 2008
Creator: Povirk, Lawrence; Yannone, Steven M.; Khan, Imran S.; Zhou, Rui-Zhe; Zhou, Tong; Valerie, Kristoffer et al.
Partner: UNT Libraries Government Documents Department

Matrix Metalloproteinase Stromelysin-1 Triggers a Cascade of Molecular Alterations that leads to stable epithelial-to-Mesenchymal Conversion and a Premalignant Phenotype in Mammary Epithelial Cells

Description: Matrix metalloproteinases (MMPs) regulate ductal morphogenesis, apoptosis, and neoplastic progression in mammary epithelial cells. To elucidate the direct effects of MMPs on mammary epithelium, we generated functionally normal cells expressing an inducible autoactivating stromelysin-1 (SL-1) transgene. Induction of SL-1 expression resulted in cleavage of E-cadherin, and triggered progressive phenotypic conversion characterized by disappearance of E-cadherin and catenins from cell-cell contacts, downregulation of cytokeratins, upregulation of vimentin, induction of keratinocyte growth factor expression and activation, and upregulation of endogenous MMPs. Cells expressing SL-1 were unable to undergo lactogenic differentiation and became invasive. Once initiated, this phenotypic conversion was essentially stable, and progressed even in the absence of continued SL-1 expression. These observations demonstrate that inappropriate expression of SL-1 initiates a cascade of events that may represent a coordinated program leading to loss of the differentiated epithelial phenotype and gain of some characteristics of tumor cells. Our data provide novel insights into how MMPs function in development and neoplastic conversion.
Date: August 11, 1997
Creator: Lochter, A.; Galosy, S.; Muschler, J.; Freedman, N.; Werb, Z. & Bissell, M.J.
Partner: UNT Libraries Government Documents Department

1Surface structure of cleaved (001) USB2 single crystal surface

Description: We have achieved what we believe to be the first atomic resolution STM images for a uranium compound USb2 taken at room temperature. The a, b, and c lattice parameters in the images confirm that the tetragonal USb2crystals cleave on the (00 I) basal plane as expected. Our calculations indicate a symmetric cut between Sb planes to be the most favorable cleavage plane and U atoms to be responsible for most ofthe density of states measured by STM. Since the spacing between Sb atoms and between U atoms is the same, STM topography only cannot unambiguously identify the surface atom species.
Date: January 1, 2009
Creator: Chen, Shao-ping
Partner: UNT Libraries Government Documents Department

An atomistic study of dynamic brittle fracture in silicon

Description: Dynamic fracture has been modeled using a modified embedded atom method (MEAM) potential for silicon. For Mode I dynamic fracture along (1 1 1) crystallographic planes, the molecular dynamics model predicts crack speeds and fracture energies in agreement with previous experimental results [l]. In this orientation, hcture occurs almost exclusively along (1 1 1) planes for energy release rates up to 30 J/m2. For Mode I fracture oriented initially on (1 10) planes, fracture occurs by cleavage on (1 10) planes for a static energy release rate (J,) less than 8 J/m2. For greater values of J,, the fracture surfaces switch to alternating (111) planes, which is in agreement with previous experimental results [2]. Crack speed predictions for the (1 10) orientation are somewhat In the atomistic simulations, the dynamically propagating cracks generate dislocations, which are primarily produced on the (1 1 1) and (1 10) planes. Differences in the type and quantity of dislocations produced have been observed for different orientations. Molecular dynamics has the ability to calculate the energy consumed by dislocations and other lattice defects produced during fracture and the total surface energy of the main crack, side branches and secondary cracks. The sum of the surface energy and the energy consumed by lattice defects determines the dynamic fracture less than the high speeds observed experimentally. toughness, J(v). The dynamic fkacture toughness has been found to vary linearly with J,. For the (111) orientation with cracks propagating in the [211] direction, J(v) asymptotically approached a value of 1/3 of J,. The remainder of the strain energy that is released during fracture is converted into kinetic energy at the crack tip during the fracture process, which occurs atom by atom.
Date: January 1, 2002
Creator: Swadener, J. G. (John G.); Baskes, M. I. (Michael I.) & Nastasi, Michael Anthony,
Partner: UNT Libraries Government Documents Department

Microbial genome program report: Optical approaches for physical mapping and sequence assembly of the Deinococcus radiodurans chromosome

Description: Maps of genomic or cloned DNA are frequently constructed by analyzing the cleavage patterns produced by restriction enzymes. Restriction enzymes are remarkable reagents that faithfully cleave only at specific sequences of between 4 and 8 nucleotides, which vary according to the specific enzymes. Restriction enzymes are reliable, numerous, and easily obtainable and presently, there are approximately 250 different sequences represented among thousands of enzymes. Restriction maps characterize gene structure and even entire genomes. Furthermore, such maps provide a useful scaffold for the alignment and verification of sequence data. Restriction maps generated by computer and predicted from the sequence are aligned with the actual restriction map. Restriction enzyme action has traditionally been assayed by gel electrophoresis. This technique separates cleaved molecules on the basis of their nobilities under the influence of an applied electrical field, within a gel separation matrix (small fragments have a greater mobility than large ones). Although gel electrophoresis distinguishes different sized DNA fragments (known as a fingerprint), the original order of these fragments remains unknown. The subsequent task of determining the order of such fragments is a labor intensive task, especially when making restriction maps of whole genomes, and therefore despite its obvious utility to genome analysis, it is not widely used.
Date: November 23, 1999
Creator: Schwartz, David C.
Partner: UNT Libraries Government Documents Department

Novel catalysts for methane activation. Quarterly report No. 12, July 1, 1995--September 30, 1995

Description: Fullerenes are a recently discovered allotrope of carbon that possess unusual properties, some of which may be ideal for methane activation. This project is designed to evaluate these carbon-based materials for conversion of methane into higher hydrocarbons. The project is divided into three technical tasks. Task 1 deals with synthesis and characterization of the fullerenes and fullerene soots, Task 2 with testing of the catalysts, and Task 3 with evaluation of the results and technical reporting. Due to money constraints we have not done any technical work during this period. However, we hope to continue our work and produce a final report including recommendations for future research when funds are available.
Date: December 1, 1995
Creator: Hirschon, A.S.; Du, Y. & Wu, H.J.
Partner: UNT Libraries Government Documents Department

Metabolic Engineering to Develop a Pathway for the Selective Cleavage of Carbon-Nitrogen Bonds

Description: The objective of the project is to develop a biochemical pathway for the selective cleavage of C-N bonds in molecules found in petroleum. Specifically a novel biochemical pathway will be developed for the selective cleavage of C-N bonds in carbazole. The cleavage of the first C-N bond in carbazole is accomplished by the enzyme carbazole dioxygenase, that catalyzes the conversion of carbazole to 2-aminobiphenyl-2,3-diol. The genes encoding carbazole dioxygenase were cloned from Sphingomonas sp. GTIN11 and from Pseudomonas resinovorans CA10. The selective cleavage of the second C-N bond has been challenging, and efforts to overcome that challenge have been the focus of recent research in this project. Enrichment culture experiments succeeded in isolating bacterial cultures that can metabolize 2-aminobiphenyl, but no enzyme capable of selectively cleaving the C-N bond in 2-aminobiphenyl has been identified. Aniline is very similar to the structure of 2-aminobiphenyl and aniline dioxygenase catalyzes the conversion of aniline to catechol and ammonia. For the remainder of the project the emphasis of research will be to simultaneously express the genes for carbazole dioxygenase and for aniline dioxygenase in the same bacterial host and then to select for derivative cultures capable of using carbazole as the sole source of nitrogen.
Date: October 1, 2005
Creator: II, John J. Kilbane
Partner: UNT Libraries Government Documents Department

Processing of 3'-Phosphoglycolate-Terminated DNA Double-StrandBreaks by Artemis Nuclease

Description: The Artemis nuclease is required for V(D)J recombination and for repair of an as yet undefined subset of radiation-induced DNA double-strand breaks. To assess the possibility that Artemis functions on oxidatively modified double-strand break termini, its activity toward model DNA substrates, bearing either 3{prime}-hydroxyl or 3{prime}-phosphoglycolate moieties, was examined. A 3{prime}-phosphoglycolate had little effect on Artemis-mediated trimming of long 3{prime} overhangs (>9 nucleotides), which were efficiently trimmed to 4-5 nucleotides. However, 3{prime}-phosphoglycolates on overhangs of 4-5 bases promoted selective Artemis-mediated trimming of a single 3{prime}-terminal nucleotide, while at least 2 nucleotides were trimmed from identical hydroxyl-terminated substrates. Artemis also efficiently removed a single nucleotide from a phosphoglycolate-terminated 3-base 3{prime} overhang, while leaving an analogous hydroxyl-terminated overhang largely intact. Such removal was dependent upon Ku, DNA-dependent protein kinase, and ATP. Together, these data suggest that Artemis-mediated cleavage of 3{prime} overhangs requires a minimum of 2 nucleotides, or a nucleotide plus a phosphoglycolate, 3{prime} to the cleavage site. Shorter 3{prime}-phosphoglycolate-terminated overhangs and blunt ends were also processed by Artemis, but much less efficiently. Consistent with the in vitro substrate specificity of Artemis, human cells lacking Artemis exhibited hypersensitivity to X-rays, bleomycin and neocarzinostatin, which all induce 3{prime}-phosphoglycolate-terminated double-strand breaks. Collectively, these results suggest that 3{prime}-phosphoglycolate termini and/or specific classes of DNA ends that arise from such blocked termini are relevant Artemis substrates in vivo.
Date: October 1, 2005
Creator: Povrik, Lawrence F.; Zhou, Tong; Zhou, Ruizhe; Cowan, Morton J. & Yannone, Steven M.
Partner: UNT Libraries Government Documents Department

IRRADIATION OF 3- SUBSTITUTED-2-PHENYLOXAZIRIDINES

Description: It was noted previously that 3-(p-dimethylamino)-2-phenyloxaziridine (I) and 3-(p-dimethylamino)-2-(m-nitrophenyl)oxaziridine were photosensitive. Further study on the irradiation (in a variety of solvents under nitrogen) of (I), 2,3-diphenyloxaziridine (II), and 3-(p-nitrophenyl)-2-phenyloxaziridine (III) indicates the major photoreaction to be cleavage to the aldehyde and an intermediate which forms aniline and azobenzene. There is also formed in the photolysis varying amounts of the corresponding anilide. A table provided gives the yields in three different solvents.
Date: August 30, 1967
Creator: Splitter, Janet S. & Calvin, Melvin.
Partner: UNT Libraries Government Documents Department

A cell nanoinjector based on carbon nanotubes

Description: Technologies for introducing molecules into living cells are vital for probing the physical properties and biochemical interactions that govern the cell's behavior. Here we report the development of a nanoscale cell injection system-termed the nanoinjector-that uses carbon nanotubes to deliver cargo into cells. A single multi-walled carbon nanotube attached to an atomic force microscope tip was functionalized with cargo via a disulfide-based linker. Penetration of cell membranes with this 'nanoneedle', followed by reductive cleavage of the disulfide bonds within the cell's interior, resulted in the release of cargo inside the cells. The capability of the nanoinjector was demonstrated by injection of protein-coated quantum dots into live human cells. Single-particle tracking was employed to characterize the diffusion dynamics of injected quantum dots in the cytosol. This new technique causes no discernible membrane or cell damage, and can deliver a discrete number of molecules to the cell's interior without the requirement of a carrier solvent.
Date: January 30, 2007
Creator: Chen, Xing; Kis, Andras; Zettl, Alex & Bertozzi, Carolyn R.
Partner: UNT Libraries Government Documents Department

A novel approach to the study of the functional proteome in breast cancer

Description: Factors including intratumoral heterogeneity and variability in tissue handling potentially hamper the application of reverse phase protein arrays (RPPA) to study of the solid tumor functional proteome. To address this, RPPA was applied to quantify protein expression and activation in 233 human breast tumors and 52 breast cancer cell lines. Eighty-two antibodies that recognize kinase and steroid signaling events and their effectors were validated for RPPA because of the importance of these proteins to breast carcinogenesis. Reproducibility in replicate lysates was excellent. Intratumoral protein expression was less variable than intertumoral expression, and prognostic biomarkers retained the ability to accurately predict patient outcomes when analyzed in different tumor sites. Although 21/82 total and phosphoproteins demonstrated time-dependent instability in breast tumors that were placed at room temperature after surgical excision for 24 hours prior to freezing, the functional proteomic 'fingerprint' was robust in most tumors until at least 24 hours before tissue freezing. Correlations between RPPA and immunohistochemistry were statistically significant for assessed proteins but RPPA demonstrated a superior dynamic range and detected, for example, an 866-fold difference in estrogen receptor alpha level across breast tumors. Protein and mRNA levels were concordant (at p {le} 0.05) for 41.3% and 61.1% of assayed targets in breast tumors and cell lines, respectively. Several phosphorylation and cleavage products did not correlate with the corresponding transcript levels. In conclusion, the reproducibility of RPPA, the faithfulness with which proteins and the functional proteomic 'fingerprint' are preserved in different sections derived from primary breast tumors, and the surprising stability of this 'fingerprint' with increasing time to freezing all facilitate the application of RPPA to the accurate study of protein biomarkers in non-microdissected tumor specimens. The lack of correlation between several protein phosphorylation and cleavage products and the corresponding transcripts underlines the importance of study of the functional proteome ...
Date: October 10, 2008
Creator: Hennessy, Bryan; Lu, Yiling; Gonzalez-Angulo, Ana Maria; Carey, Mark; Myhre, Simen; Ju, Zhenlin et al.
Partner: UNT Libraries Government Documents Department

Oxidative cleavage of erucic acid for the synthesis of brassylic acid

Description: The main focus of this work is to synthesize Brassylic Acid (BA) using oxidative cleavage of Erucic Acid (EA). Crambe (Crambe abyssinica) is an industrial oilseed grown in North Dakota. Crambe has potential as an industrial fatty acid feedstock as a source of Erucic acid (EA). It has approximately 50-60 % of EA, a C{sub 22} monounsaturated fatty acid. Oxidative cleavage of unsaturated fatty acids derived from oilseeds produces long chain (9, 11, and 13 carbon atoms) dibasic and monobasic acids. These acids are known commercial feedstocks for the preparation of nylons, polyesters, waxes, surfactants, and perfumes. Other sources of EA are Rapeseed seed oil which 50-60 % of EA. Rapeseed is grown outside USA. The oxidative cleavage of EA was done using a high throughput parallel pressure reactor system. Kinetics of the reaction shows that BA yields reach a saturation at 12 hours. H{sub 2}WO{sub 4} was found to be the best catalyst for the oxidative cleavage of EA. High yields of BA were obtained at 80 C with bubbling of O{sub 2} or 10 bar of O{sub 2} for 12 hours.
Date: October 29, 2010
Creator: Nasrullah, Mohammed J.; Thapliyal, Pooja; Pfarr, Erica N.; Dusek, Nicholas S.; Schiele, Kristofer L. & Bahr, James A.
Partner: UNT Libraries Government Documents Department

Estimation of brassylic acid by gas chromatography-mass spectrometry

Description: The main focus of this work is to estimate Brassylic Acid (BA) using gas chromatography-mass spectrometry (GC-MS). BA is a product obtained from the oxidative cleavage of Erucic Acid (EA). BA has various applications for making nylons and high performance polymers. BA is a 13 carbon compound with two carboxylic acid functional groups at the terminal end. BA has a long hydrocarbon chain that makes the molecule less sensitive to some of the characterization techniques. Although BA can be characterized by NMR, both the starting material (EA) and products BA and nonanoic acid (NA) have peaks at similar {delta}, ppm values. Hence it becomes difficult for the quick estimation of BA during its synthesis.
Date: October 29, 2010
Creator: Mohammed J. Nasrullah, Erica N. Pfarr, Pooja Thapliyal, Nicholas S. Dusek, Kristofer L. Schiele, Christy Gallagher-Lein, and James A. Bahr
Partner: UNT Libraries Government Documents Department

Linkages between aromatic structures in the Argonne Premium Coal Samples

Description: The objective of this study is to elucidate the nature of the important linkages between aromatic clusters and variations of these links with coal rank. From studies using methods such as NMR and mass spectrometry, the authors have considerable information on the size and types of aromatic clusters in the Argonne coals. In this study, extracts, model polymers, extracted coals, and modified coals are examined by temperature resolved high resolution mass spectrometry. There is evidence that strong bond cleavage may be very important for volatile release in pyrolysis of higher rank coals.
Date: April 1, 1997
Creator: Winans, R.E. & Tomczyk, N.A.
Partner: UNT Libraries Government Documents Department

[Development, implementation and testing of highly efficient algorithms for evaluation and analysis of electronic structures]. Progress report, April 1, 1995--July 31, 1996

Description: This study has involved the following investigations: (1) Energetics and site specificity of the homolytic C-H bond cleavage in benzenoid hydrocarbons; (2) Nonclassical aryl radicals; (3) Regularities in energies and geometries of biaryls; (4) Energetics of homolytic C-H and C-Cl bond cleavages in polychlorobenzenes; and (5) Cyclodehydrogenation of 1-phenylnaphthalene to fluoranthene. Pyrolysis of simple polycyclic aromatic hydrocarbons (PAHs), which produces complex mixtures of biaryls, pericondensed PAHs, and soot, constituted the common focus of the electronic structure studies. The biaryls and pericondensed PAHs are both potent carbinogens and significant pollutants.
Date: December 31, 1996
Creator: Cioslowski, J. & Moncrieeff, D.
Partner: UNT Libraries Government Documents Department

Theoretical studies of pentene cracking on zeolites: C-C beta-scission processes

Description: The nature of the molecular species involved in the cracking of hydrocarbons into smaller fragments over zeolite catalysts has been studied extensively, as the advent of zeolites such as faujasite to carry out these transformations more selectively has revolutionized the petroleum refining technology. While the nature of the acid-catalyzed process involving proposed carbocationic species has been proposed for nearly fifty years, there have been extensive studies involving heterogeneous processes and analogs with solution superacid chemistry to elucidate these mechanisms more clearly and to attempt to detect the intermediates involved in these reactions. Also in recent years there have been an increasing number of theoretical studies on the nature of the acid sites in zeolites, the interactions of these acid sites with adsorbates including hydrocarbons, and on simple reactions of hydrocarbon species using model systems to represent the zeolite. In this study the authors report the results of ab initio and density functional studies on one aspect--the beta-scission C-C bond-breaking step--that arises in the cracking process of alkanes and alkenes. The authors focus on the species arising from pentene adsorption on an acid site and the subsequent cracking of this C{sub 5} species as an illustration of the carbon-carbon bond-breaking step. In these studies they employ a simple three-T-site to represent the immediate vicinity of the acid site in faujasite comprised of the Si-O-Al-OH-O-Si skeleton with the unsatisfied bonds terminated by hydrogens. They study the reaction of the 2-pentyl cation undergoing beta-scission in the gas phase to form propene and the ethyl cation and the corresponding reaction on the zeolite cluster. The structures of the reactants, products and transition states are determined using ab initio electronic structure techniques.
Date: April 1, 1997
Creator: Hay, P.J.; Redondo, A. & Guo, Y.
Partner: UNT Libraries Government Documents Department

Brittle fracture in Nd{sub 2}Fe{sub 14}B intermetallic magnets

Description: Efforts to understand and improve the fracture toughness of Nd{sub 2}Fe{sub 14}B permanent magnets require an understanding of the fracture process itself. Cleavage plane orientations in Nd{sub 2}Fe{sub 14}B were identified by X-ray diffraction and found to be rather random. Cleavage fracture surfaces often exhibited smooth curvatures with no evidence for cleavage steps. The small grain sizes of less than 100 nm in Magnequench MQ material preclude an easy assessment of the fracture mode by scanning electron microscopy. Auger electron spectroscopy showed that much of the surface is covered with a 1 nm thick layer of a neodymium-rich phase presumably the 70Nd-30Fe eutectic phase suggesting that the hard Nd{sub 2}Fe{sub 14}B grains do not cleave but instead failure is at or in the grain boundary phase.
Date: February 1998
Creator: Horton, J. A.; Heatherly, L.; Specht, E. D.; Li, D.; Herchenroeder, J. W. & Canfield, P. C.
Partner: UNT Libraries Government Documents Department