gebhart/patrepeval huggingface dataset:
Improving Performance of Low Density Drill in Fluids with Hollow Glass Spheres (2003)

Abstract The increasing number of open hole horizontal well completions in low-pressure and depleted reservoirs requires the use of non-damaging low-density drill-in fluids (LDDIF) to avoid formation damage and realize optimum well productivity. To address this need we have formulated new LDDIFs with specific density lower than 1.0 sg (8.34 ppg) specifically to drill and complete low pressure and depleted reservoirs with minimum formation damage and maximum production. These materials exhibit typical drilling fluid characteristics, allowing the well to be safely drilled to required well depth, but also perform as completion fluids, lessening formation damage to a greater extent than fluids with greater density and higher wellbore pressures. The new LDDIF incorporates low-density hollow glass spheres (HGS) to allow near-balanced drilling in low pressure and depleted reservoirs. The LDDIF uses potassium chloride (KCl) brine as the base fluid because of its low density and inhibition of clay hydration and employs low concentrations of the HGS so that fluid rheology is not altered. We have conducted extensive laboratory testing to compare performance of the HGS LDDIF with that of conventional horizontal well DIFs. Experiments consisted of permeability regain tests on unconsolidated sands with sand control screens. Test variables included temperature, concentration of drill solids, cleanup technique and HGS concentration. Test results have shown that the new fluids are up to 50% easier to remove from the wellbore formation faces and provide higher productivity than higher density fluids. Such results indicate that higher well productivity from wells with less impairment would offset any added costs of HGS additives in the fluids.
Majorana state on the surface of a disordered three-dimensional topological insulator (2012)

We study low-lying electron levels in an ``antidot'' capturing a coreless vortex on the surface of a three-dimensional topological insulator in the presence of disorder. The surface is covered with a superconductor film with a hole of size $R$ larger than coherence length, which induces superconductivity via proximity effect. Spectrum of electron states inside the hole is sensitive to disorder, however, topological properties of the system give rise to a robust Majorana bound state at zero energy. We calculate the subgap density of states with both energy and spatial resolution using the supersymmetric $\ensuremath{\sigma}$ model method. We identify the presence of the Majorana fermion with symmetry class $B$. Tunneling into the hole region is sensitive to the Majorana level and exhibits resonant Andreev reflection at zero energy.
Functional angiotensin II receptors in cultured vascular smooth muscle cells. (1982)

To study cellular mechanisms influencing vascular reactivity, vascular smooth muscle cells (VSMC) were obtained by enzymatic dissociation of the rat mesenteric artery, a highly reactive, resistance-type blood vessel, and established in primary culture. Cellular binding sites for the vasoconstrictor hormone angiotensin II (AII) were identified and characterized using the radioligand 125I-angiotensin II. Freshly isolated VSMC, and VSMC maintained in primary culture for up to 3 wk, exhibited rapid, saturable, and specific 125I-AII binding similar to that seen with homogenates of the intact rat mesenteric artery. In 7-d primary cultures, Scatchard analysis indicated a single class of high-affinity binding sites with an equilibrium dissociation constant (Kd) of 2.8 +/- 0.2 nM and a total binding capacity of 81.5 +/- 5.0 fmol/mg protein (equivalent to 4.5 x 10(4) sites per cell). Angiotensin analogues and antagonists inhibited 125I-AII binding to cultured VSMC in a potency series similar to that observed for the vascular AII receptor in vivo. Nanomolar concentrations of native AII elicited a rapid, reversible, contractile response, in a variable proportion of cells, that was inhibited by pretreatment with the competitive antagonist Sar1,Ile8-AII. Transmission electron microscopy showed an apparent loss of thick (12-18 nm Diam) myofilaments and increased synthetic activity, but these manifestations of phenotypic modulation were not correlated with loss of 125I-AII binding sites or hormonal responsiveness. Primary cultures of enzymatically dissociated rat mesenteric artery VSMC thus may provide a useful in vitro system to study cellular mechanisms involved in receptor activation-response coupling, receptor regulation, and the maintenance of differentiation in vascular smooth muscle.
Halogen Azide Displacement to Prepare Some Symmetrically Substituted β‐Cyclodextrin Derivatives (1990)

Abstract The heptakis (2,3‐di‐O‐acetyl‐6‐bromo‐6‐deoxy)‐β‐cyclodextrin has been converted to the 6‐azido derivate with 82% yield, then deacetylated by the Zemplén 's method (yield 75%) and methylated by methyl‐iodide (yield 66%), to heptakis (2,3‐di‐O‐methyl‐6‐azido‐6‐deoxy)‐β‐cyclodextrin, which is an appropriate intermediary toward methylated amino‐CD‐derivatives. The structure of all compounds were unambiguously proven by NMR spectroscopy.
Alternating poly(ester amide)s from succinic anhydride and α,ω‐amino alcohols: synthesis and thermal characterization (2003)

Abstract Alternating poly(ester amide)s 6a – e from succinic anhydride and α,ω‐amino alcohols H 2 N—(CH 2 ) x —OH ( x = 2–6) 2a–e were obtained in two steps: α‐carboxyl‐ω‐hydroxy amides 3a–e were prepared from the starting materials in a highly selective reaction, followed by a polycondensation reaction. 1 H and 13 C NMR analyses of the poly(ester amide)s clearly reveal the alternating microstructure. The poly(ester amide)s with homologous α,ω‐amino alcohols H 2 N—(CH 2 ) x —OH ( x = 2–6) are semi‐crystalline materials, their melting points show the odd/even effect observed for [n]‐polyamides and [n]‐polyurethanes. Heating the poly(ester amide)s 6a–e yields the corresponding N ‐(hydroxyalkyl) imides 4a–e with no trace of cyclic ester amides. Theoretical calculations revealed that the cyclic ester amides 5a–e are clearly richer in energy than the isomeric N ‐(hydroxyalkyl) imides. These results show that cyclic ester amides can not be prepared from N ‐(hydroxyalkyl) imides by ring‐enlargement reactions. Copyright © 2003 Society of Chemical Industry
The Synthesis and Microbiological Properties of β-(2-Benzothienyl)-α-aminopropionic Acid<sup>1a</sup> (1948)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe Synthesis and Microbiological Properties of β-(2-Benzothienyl)-α-aminopropionic Acid1aSouren Avakian, Jack Moss, and Gustav J. MartinCite this: J. Am. Chem. Soc. 1948, 70, 9, 3075–3076Publication Date (Print):September 1, 1948Publication History Published online1 May 2002Published inissue 1 September 1948https://doi.org/10.1021/ja01189a070Request reuse permissionsArticle Views83Altmetric-Citations20LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (265 KB) Get e-Alertsclose Get e-Alerts
Seamless integration of an 8/spl times/2.5 Gb/s WDM-PON and radio-over-fiber using all-optical up-conversion based on Raman-assisted FWM (2005)

We experimentally demonstrate the seamless integration of an 8/spl times/2.5 Gb/s wavelength-division-multiplexing passive optical network and radio-over-fiber access system using all-optical up-conversion based on Raman-assisted four-wave mixing in a high-nonlinear fiber. Dispersion-limited reach is extended to >20 km through vestigial-sideband filtering.
Optical Equalization of Fiber Chromatic Dispersion in a 5-Gbit/s Transmission System (1990)

Chromatic dispersion in conventional single-mode fiber can cause serious degradations in the performance of optical communication systems operating in the low-loss region around a wavelength of 1.5-μm. Direct on-off keying of single-frequency semiconductor lasers results in linewidth broadening, or “chirp”, due to modulation-induced changes in the carrier density [1]. This broadening, when combined with fiber dispersion of 15–20 psec/km · nm, causes intersymbol interference in the received optical pulses and limits the bit rate and distance of operation. Low-chirp, 1.5-μm lasers have been used in laboratory systems operating at up to 4 Gbit/s over 100 km of conventional fiber [2].
A Double-Piped iterated hash function based on a hybrid of chaotic maps (2008)

A novel iterated hash function based on Double-Pipe structure and the combination of Chebyshev chaotic map and piecewise linear chaotic map (PWLCM) is described in this paper. This function encodes a message of arbitrary length into a hash value with a fixed 128-bit length. For the proposed function, we conduct the following performance analyses: one-way property analysis, statistic analysis of diffusion and confusion, attacks resistance analysis and key space analysis. The results indicate that the function has desirable security properties which make it a suitable choice for data integrity applications.
The Life Span of Red Cells in the Rat and the Mouse as Determined by Labeling with DFP32 in Vivo (1958)

Abstract The red cells of rats and mice were tagged in vivo by injection of diisopropylphosphorofluoridate (DFP), labeled with P32, and the disappearance of radioactivity from the circulating red cells was determined. From the data obtained, it is concluded that the disappearance of the red cells is linear with time and that the red cells in both rats and mice have a true life span without measurable random destruction. The life span of the erythrocytes was found to be 60.0 ± 3.2 (S.D.) days in the rat and 40.7 ± 1.9 (S.D.) days in the mouse. Especially in the mouse the determination of the red cell life span with DFP32 is a simple procedure.
Binding of nonsubstrate ligands to the glutathione S-transferases. (1975)

Fluorescence spectroscopy and inhibition kinetics were used to quantitate the affinity of nonsubstrate ligands for the rat liver glutathione S-transferases AA, A, B, and C in the presence of glutahione. The dissociation constants KD, for ligands such as bilirubin, indocyanine green, and hematin were determined by measuring the decrease in the intrinsic fluorescence of the proteins attendant on the addition of ligand. A second technique, used for compounds which absorb strongly at the excitation maxima of tryptophan, was to utilize 8-anilinonaphthalen sulfonate in the formation of protein complex fluorescing at a higher wavelength. The quenching of this complex allowed the determination of the dissociation constants for ligands such as 3,6-dibromosulfophthalein and cephalothin. These data indicate that all four proteins bind these ligands but do so with different affinities. The bilirubin-induced decrease in fluorescence was used to estimate the stoichiometry of binding as 1.2 mol of bilirubin bound/mol of transferase B and 0.7 mol/mol of transferase C. All of the ligands examine are inhibitors of catalytic activity, as tested in a standard assay with GSH and 1-chloro-2,4-dinitrobenzene as substrates. From these studies we conclude that these proteins have a broad specificity not only for their substrates, but for the binding of nonsubstrate ligands as well.
An Interoperable Approach to Multifactor Identity Verification (2009)

Naming heterogeneity occurs in digital identity management systems when the various parties involved in managing digital identities use different vocabularies to denote identity attribute names. To resolve potential interoperability issues due to naming heterogeneity, the authors propose a new protocol that uses lookup tables, dictionaries, and ontology mapping techniques.
<i>In situ</i>characterization of NiTi based shape memory thin films by optical measurement (2006)

In this note, we present an alternative in situ approach to determine the phase transformation temperatures of sputter deposited NiTi based shape memory thin films atop a substrate. Reflection in three thin films upon thermal cycling was measured with a reflection spectrometer in a wavelength range from 360 nm to 2 µm. Subsequently, the relationship of the reflection change versus temperature was obtained, which shows obvious hysteresis, clear evidence of the phase transformation. Hence, the transformation temperatures were determined and then compared with the result of the differential scanning calorimeter test; good agreement was observed. Additionally, we started modeling the phenomenon by identifying and quantitatively estimating four potential contributors to the change of reflection during phase transformation in deposited shape memory thin films.
Dual Inhibition of EGFR with Afatinib and Cetuximab in Kinase Inhibitor–Resistant <i>EGFR</i> -Mutant Lung Cancer with and without T790M Mutations (2014)

This article reports the results of a trial combining afatinib and cetuximab in patients with acquired resistance and details the first clinical proof-of-concept for the preclinical hypothesis that a significant proportion of tumors in patients with acquired resistance to gefitinib/erlotinib remain dependent on EGFR signaling for survival.
Electron Paramagnetic Resonance Imaging of Tumor pO<sub>2</sub> (2012)

Electron paramagnetic resonance imaging (EPRI) can be used to noninvasively and quantitatively obtain three-dimensional maps of tumor pO₂. The paramagnetic tracer triarylmethyl (TAM), a substituted trityl radical moiety, is not toxic to animals and provides narrow isotropic spectra, which is ideal for in vivo EPR imaging experiments. From the oxygen-induced spectral broadening of TAM, pO₂ maps can be derived using EPRI. The instrumentation consists of an EPRI spectrometer and 7T magnetic resonance imaging (MRI) system both operating at a common radiofrequency of 300 MHz. Anatomic images obtained by MRI can be overlaid with pO₂ maps obtained from EPRI. With imaging times of less than 3 min, it was possible to monitor the dynamics of oxygen changes in tumor and distinguish chronically hypoxic regions from acutely hypoxic regions. In this article, the principles of pO₂ imaging with EPR and some relevant examples of tumor imaging are reviewed.
Fast thresholding based on improved minimum cross entropy (2012)

Image segmentation is an important and classic problem in image processing and computer vision. Thresholding is applied to many fields, because of its less computation and stable performance. The key of thresholding method is to determine the adaptive threshold. In order to segment biological image effectively, a new adaptive thresholding method is proposed. First, two dimension minimum entropy is computed based on gray-gradient co-occurrence matrix; and then the genetic algorithm is applied to encode the two-dimension threshold vector; Finally, the optimum threshold is calculated based on fitness function and uniformity measurement(UM). Experimental results show that this method has three advantages: 1) improve computational efficiency so that it can run in real time; 2) retain more object and edge information so that it can meet the practical requirement; 3) robust to the uneven distribution of light.
A high density datapath layout generation method under path delay constraints (2002)

A novel method for producing high-density datapath layouts under path delay constraints is proposed. The authors have adopted an array-compiler for generating layouts of functional blocks, and a place-and-route program for generating an overall layout. For linear placement of functional blocks, they have applied the A-algorithm with a new cost function which has the terms of path delay constraints and track number. This makes it possible to find a placement of functional blocks which leads to a high-density datapath layout that satisfies all path delay constraints. With the proposed method, the authors successfully generated several datapath layouts realizing the desired performance. The density of the layout ranges from 6.1 to 8.5Ktr./mm/sup 2/, which is sufficiently high.
Conversion of Aromatics. (1945)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTConversion of Aromatics.R. C. Hansford, C. G. Myers, and A. N. SachanenCite this: Ind. Eng. Chem. 1945, 37, 7, 671–675Publication Date (Print):July 1, 1945Publication History Published online1 May 2002Published inissue 1 July 1945https://doi.org/10.1021/ie50427a019RIGHTS & PERMISSIONSArticle Views59Altmetric-Citations11LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (697 KB) Get e-Alerts
Iron changes in natural and Fe(III) loaded montmorillonite during carbon nanotube growth (2006)

A detailed elaboration of the transformations of iron species, present in natural and Fe(NO(3))(3) loaded montmorillonite, during carbon deposition and carbon nanotube growth is described. According to transmission electron microscopy results, deposited carbon atoms form fibres in the case of pristine montmorillonite and multiwalled carbon nanotubes in the case of Fe(III) loaded montmorillonite. Mössbauer and x-ray diffraction analysis results point to an extensive reduction of structural and intercalated Fe(III) cations to Fe(II) with the latter migrating from the interlayer space to the vacant octahedral sites of the mineral's lattice. Such migration of the non-structural iron catalyst prohibits extensive contamination of the final composite with various metal catalyst impurities. The crucial role of the active catalytic centres in the formation of carbon nanotubes is ascribed to a minor quantity of iron, found entrapped in the carbon nanostructures, which, at the end of the reaction, is identified as iron carbide. The interesting formation of a nanometric γ-iron precipitate is also detected, which is probably stabilized through strong interactions with the lattice of montmorillonite. Finally, it is demonstrated that iron-rich natural clay minerals can serve as direct catalysts for carbon nanotube growth.
Influences of Permeation of Vanadium Ions through PVDF-g-PSSA Membranes on Performances of Vanadium Redox Flow Batteries (2005)

The preparation and physical characterization of a poly(vinylidene fluoride)-graft-poly(styrene sulfonic acid) (PVDF-g-PSSA) membrane prepared by a solution-grafting method were described. These membranes exhibited high conductivity with a value 3.22 x 10(-2) S/cm at 30 degrees C. ICP studies revealed that the PVDF-g-PSSA membrane showed dramatically lower vanadium ion permeability compared to Nafion 117. Trivalent vanadium ions had the highest permeability through all these membranes in contrast to pentavalent vanadium ions with the lowest. The VRB with the low-cost PVDF-g-PSSA membrane exhibited a higher performance than that with Nafion 117 under the same operating conditions, and its energy efficiency reached 75.8% at 30 mA/cm(2). The performance of VRB with the PVDF-g-PSSA membrane can be maintained after more than 200 cycles at a current density of 60 mA/cm(2).
Synthesis, structure, and properties of polyimide and polyurethane‐urea‐imide copolymers (2003)

Abstract Several, novel polyimide–polyurethane‐urea‐imide (PI‐PUI) copolymers with different polyimide (PI) contents were prepared by an in situ interpenetrating reaction between polyurethane‐urea‐imide (PUI) precursor and poly(amide acid). Changing the ratio of the PUI precursor and poly(amide acid) resulted in a change of the properties of the PI‐PUI copolymers from plastic to elastomer. Fourier transform infrared spectra revealed the characteristic absorption bands of PI‐PUI copolymers; differential scanning calorimetry (DSC) analyses revealed that the glass‐transition temperature of the soft‐segment‐rich phase decreased as the PI content increased in PI‐PUIs, meaning that the soft segments (i.e., PEG) were more incompatible and had better crystallizability with a high‐PI‐segment content in PI‐PUI. Wide‐angle X‐ray diffraction curves exhibited more ordered structure within the disordered PI‐PUI copolymer's state with an increasing PI content, which further agreed with the DSC results. Scanning electron micrographs clearly showed that the molecular chains in PI‐PUI with a high‐PI‐content packed, ordered lamellar structure. Thermogravimetric curves indicated that the heat resistance of PI‐PUI was better than pure PUI. The introduction of the PI component into PUI by an in situ interpenetrating reaction method is an effective way to improve the thermal stability and solvent resistance of PUI. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 216–225, 2004
Automatic Recording Torsional Magnetic Susceptibility Balance (1955)

A torsional magnetic susceptibility balance suitable for studying the de Haas-van Alphen effect has been developed in which the torque and magnetic field are recorded continuously while the magnet current is reduced automatically. The torque is recorded as a bucking current to a galvanometer suspension supporting the sample, and the magnetic field is obtained from a recording of the magnet current. A circuit for stabilizing the magnet current is also described.
Increasing the number of series FBG sensors in WDM network using a genetic algorithm (2008)

Based on the principle of the wavelength division multiplex (WDM), a data processing method which can increase the number of fiber Bragg grating (FBG) sensors in series is given. In this method, genetic algorithm (GA) is used to detect the Bragg wavelength of FBG. Simulations and experiments demonstrated that the Bragg wavelength can be detected when a crosstalk exists, even if the spectrums of two FBGs are fully overlapped.