gebhart/patrepeval huggingface dataset:
Bis(trimethylsilyl)benzamidinate: a promising spectator ligand in organoyttrium chemistry. Synthesis and reactivity of {[C6H5C(NSiMe3)2]2Y-.mu.-R}2 (R = H, C.tplbond.CH) and x-ray structure of {[C6H5C(NSiMe3)2]2Y-.mu.-C.tplbond.CH}2 (1993)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTBis(trimethylsilyl)benzamidinate: a promising spectator ligand in organoyttrium chemistry. Synthesis and reactivity of {[C6H5C(NSiMe3)2]2Y-.mu.-R}2 (R = H, C.tplbond.CH) and x-ray structure of {[C6H5C(NSiMe3)2]2Y-.mu.-C.tplbond.CH}2Robbert Duchateau, Cornelis T. van Wee, Auke Meetsma, and Jan H. TeubenCite this: J. Am. Chem. Soc. 1993, 115, 11, 4931–4932Publication Date (Print):June 1, 1993Publication History Published online1 May 2002Published inissue 1 June 1993https://pubs.acs.org/doi/10.1021/ja00064a081https://doi.org/10.1021/ja00064a081research-articleACS PublicationsRequest reuse permissionsArticle Views518Altmetric-Citations156LEARN 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 InRedditEmail Other access optionsGet e-AlertscloseSupporting Info (4)»Supporting Information Supporting Information Get e-Alerts
High-Rate Communication for Underwater Acoustic Channels Using Multiple Transmitters and Space–Time Coding: Receiver Structures and Experimental Results (2007)

In this paper, we consider the use of multiple antennas and space-time coding for high data rate underwater acoustic (UWA) communications. Recent advances in information theory have shown that significant capacity gains can be achieved by using multiple-input-multiple-output (MIMO) systems and space-time coding techniques for rich scattering environments. This is especially significant for the UWA channel where the usable bandwidth is severely limited due to frequency-dependent attenuation. In this paper, we propose to use space-time coding and iterative decoding techniques to obtain high data rates and reliability over shallow-water, medium-range UWA channels. In particular, we propose to use space-time trellis codes (STTCs), layered space-time codes (LSTCs) and their combinations along with three low-complexity adaptive equalizer structures at the receiver. We consider multiband transmissions where the available bandwidth is divided into several subbands with guard bands in between them. We describe the theoretical basis of the proposed receivers along with a comprehensive set of experimental results obtained by processing data collected from real UWA communications experiments carried out in the Pacific Ocean. We demonstrate that by using space-time coding at the transmitter and sophisticated iterative processing at the receiver, we can obtain data rates and spectral efficiencies that are not possible with single transmitter systems at similar ranges and depths. In particular, we have demonstrated reliable transmission at a data rate of 48 kb/s in 23 kHz of bandwidth, and 12 kb/s in 3 kHz of bandwidth (a spectral efficiency of 4 bs <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> Hz <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> ) at a 2-km range.
Velocity structure from forward modeling of the eastern ridge‐transform intersection area of the Clipperton Fracture Zone, East Pacific Rise (1997)

In the spring of 1994, we undertook an extensive geophysical study of the Clipperton Fracture Zone (FZ) on the fast spreading East Pacific Rise. The Clipperton Area Seismic Study to Investigate Compensation experiment (CLASSIC) included surveys to examine the deep structures associated with the fracture zone and adjacent northern ridge segment. In this paper, we report the results from five seismic profiles acquired over the eastern ridge‐transform intersection (RTI), including profiles over the RTI high, the northern ridge segment, and the eastern transform region. The travel time data for crustal phases, Moho reflections, and mantle phases were modeled using two‐dimensional ray tracing. Seismic profiles reveal that the crust is similar in thickness north and south of the Clipperton FZ, despite differences in axial topography that have previously been interpreted in terms of differences in magma supply. When compared to older crust, the northern ridge axis is characterized by lower seismic velocities and higher attenuation. In our model, a low‐velocity zone exists beneath the ridge axis, probably associated with a zone of partial melt and/or very high temperatures. Within the transform zone, we find that the southeastern trough is underlain by nearly normal crustal structure. The crust is slightly thinner than the adjacent aseismic extension but not enough to compensate for the depths of the trough. Toward the RTI, the trough is replaced by an intersection high which appears underlain by a thickened crust, and a thicker upper crustal section. Both characteristics indicate that the intersection high is a volcanic feature produced by excess volcanism at the intersection. The volcanism acts to “fill in” the transform trough, creating the thicker crust that extends under the eastern aseismic extension of the transform. Our results show that the northern ridge segment, often identified as magma‐starved, displays the crustal thickness and apparent signal attenuation characteristic of a plentiful, but perhaps episodic, magma supply.
The elusive methene ylides CH<sub>2</sub>CIH, CH<sub>2</sub>FH and CH<sub>2</sub>OH<sub>2</sub> (1988)

Abstract The possible existence of the ylides CH 2 CIH, CH 25 FH and CH 2 OH 2 as stable neutral species in the gas phase has been investigated by the neutralization–reionization (NR) mass spectrometry of their radical cations using a double‐focusing mass spectrometer of reversed geometry. The experiments were, for the most part, performed under single‐collision conditions with Xe as the neutralization target gas and He and O 2 as reionization agents. For each ylidion a peak was observed in their NR mass spectrum which indicated that the neutral ylide had apparently been produced. However for CH 2 FH + ˙ and CH 2 OH 2 + ˙ the m / z 34 and m / z 32 peaks, respectively, were attribut‐able to interferences from the natural isotopic abundance of ions of lower mass. For CH 2 CIH + ˙, the NR recovery signal was found to arise from the presence of CH 3 CI + ˙ as an impurity in the ylidion flux. This was proved by examination of the collisional activation mass spectra of the [C, H 3 , CI] + ˙ ions produced in the NR mass spectra of the conventional ions and ylidions, an experiment performed using a triple‐sector mass spectrometer.
Kinetics of reactions between neutral free radicals. Rate constants for the reaction of CH radicals with N atoms between 216 and 584 K (1996)

Rate constants have been determined for the reaction between CH radicals and N atoms at temperatures between 216 and 584 K. Discharge-flow methods were used to generate known steady-state concentrations of N atoms in a cell which could either be heated within an oven or cryogenically cooled. CH radicals were produced, in concentrations much smaller than those of the atomic radicals, by pulsed laser photolysis (PLP) of a small concentration of CHBr3 introduced into the gas flow, and their first-order kinetic decays were observed using the time-resolved laser-induced fluorescence (LIF) technique. The rate constants show only a slight dependence on temperature in the range covered in the present experiments and they are fitted by the functional form: (k1(T)/cm3 molecule–1 s–1=(1.66± 0.12)× 10–10(T/298)(–0.09 ± 0.2) where the errors are single standard deviations. If corrections are made to allow for the effects of electronic degeneracies and near degeneracies (Smith and Stewart, J. Chem. Soc. Faraday Trans., 1994, 90, 3221), rate constants, k′1(T), can be derived for just that fraction of collisions which occur on the potential-energy surfaces assumed to lead to reaction. The values of k′1(T)/cm3 molecule–1 s–1 fit the expression (3.4 ± 0.25)× 10–10(T/298)(0.04 ± 0.2), suggesting that the rate of reaction is determined by ‘capture’ on the long-range potentials which correlate adiabatically with reagents and products. It is proposed that the value k1(T)/cm3 molecule–1 s–1= 2.0 × 10–10 is used in chemical models of dense interstellar clouds.
Metal ion catalysis in nucleophilic displacement reactions at carbon, phosphorus, and sulfur centers. II. Metal ion catalysis in the reaction of <i>p</i>-nitrophenyl diphenylphosphinate with alkali metal phenoxides in ethanol (1990)

The reactions of p-nitrophenyl diphenylphosphinate (1) with lithium, sodium, potassium, and benzyltrimethylammonium phenoxides (BTMAOPh) have been studied by spectrophotometric techniques in anhydrous ethanol at 25 °C. The reactivity (k obs ) of the alkali metal phenoxides increases in the order BTMAOPh < KOPh < NaOPh < LiOPh. The rate of reaction of 1 with LiOPh is enhanced when lithium salts (LiSCN, LiNO 3 , LiClO 4 , LiOAc) are added to the reaction media. The addition of the alkali metal complexing agents dicyclohexyl-18-crown-6 ether or [2.2.2]cryptand for Na + , and [2.1.1]cryptand for Li + , to each of the alkali metal phenoxide reactions resulted in a decrease in rate, indicating catalysis by the alkali metal ions. The kinetic data are analyzed to obtain specific rate coefficients of reactions of phenoxide and ethoxide as the dissociated ions and as alkali metal – phenoxide ion pairs. Reactivities follow the order [Formula: see text]; [Formula: see text]; [Formula: see text]; [Formula: see text]. A mechanism is proposed in which the ion-paired metal phenoxide is more reactive towards the substrate than is the dissociated phenoxide. Analysis of the data in terms of initial state and transition state interactions with metal ions indicates that the increased reactivity of the ion-paired species results from greater stabilization of the negatively charged transition state relative to stabilization of the ion-paired nucleophile. Keywords: nucleophilic displacement at phosphorus by phenoxide, alkali-metal-ion catalysis.
5‐Substituted Nucleosides in Biochemistry and Biotechnology (2008)

This chapter contains sections titled: Introduction Synthesis Incorporation of C-5-Substituted Pyrimidine Nucleotides into Nucleic Acids through Modified Nucleotide 5′-Triphosphates C-5 Substituents that Stabilize DNA Duplexes Photochemistry Conclusions References
Glomus Tumor in Hand (1996)

Glomus tumor of the hand is benign tumor that arises from the neuromyoarterial apparatus. The most common site for a glomus tumor is the distal phalanx. Glomus tumors make up 1 to 4.5 per cent of all tumors of the hand and wrist. They frequently display a classic triad of symptoms: pain, tenderness and temperature sensitivity. Eight treated cases were reported in this series. All were female patients with a mean age of forty one years-old. All except one cases suffered from the classic triad of symptoms. The mean duration from onset of symptom to diagnosis was about 8 years. MRI (Magnetic Resonance Imaging) examinations depicted the tumors in excellent detail and fascilitated diagnosis in the four patients without suungual blue discoloration. All patients received radical excision and pathologic confirmation. All except one tumor were located in the subungual region. The post operation course was rather smooth and no sequelae remained. High-revolution MRI, providing a clear contrast between tumorous and normal tissues, has proved to be a useful, non-invasive method for imaging glomus tumors of the hand.
Associations Between Matrix Metalloproteinase‐8 and ‐14 and Myeloperoxidase in Gingival Crevicular Fluid From Subjects With Progressive Chronic Periodontitis: A Longitudinal Study (2010)

We present initial data that show that GCF levels and associations between MPO and MMP-8 are related to progression episodes and treatment responses in patients with chronic periodontitis. Our results suggest an interaction between the MPO oxidative pathway and MMP-8 activation, and this cascade might be useful as a potential biomarker for treatment outcomes.
Evolving Epidemiologic Characteristics of Invasive Group A Streptococcal Disease in Utah, 2002–2010 (2012)

The epidemiologic characteristics of invasive GAS disease in Utah has changed substantially over the past decade, including a significant increase in the overall incidence of invasive disease-driven primarily by increasing disease in younger persons-that coincided temporally with a decrease in the incidence of acute rheumatic fever.
Retinal Cytokine Response in Mouse Alkali-Burned Eye (1998)

The kinetics of inflammatory cytokines in sensory retina of mice with corneal alkali-burned eyes were examined. Retinal samples were collected from ICR mice with unburned and alkali-burned eyes from day 3 to day 14. Enzyme-linked immunosorbent assay was used to quantitate the expression levels of interleukin-1 alpha (IL-1 alpha), IL-1 beta and IL-6. Concentrations of IL-1 beta and IL-6 were significantly elevated at day 3 after alkali burn, and reduced to normal level by day 7. The concentration of IL-1 alpha was below assay sensitivity at all times. A significant elevation of IL-1 beta and IL-6 in the sensory retina may contribute to the retinal inflammatory response in the alkali-burned eyes. This is the first report suggesting that the retina is involved in the damage process of alkali burn.
A new class of laser dyes, 2-oxa-bicyclo[3.3.0]octa-4,8-diene-3,6-diones, with unity fluorescence yield (2006)

A new class of highly fluorescent dyes, 4,8-diphenyl-2-oxa-bicyclo[3.3.0]octa-4,8-diene-3,6-diones (1a-c), have been synthesized, they all exhibit unity fluorescence quantum yield and short radiative lifetime (< 4 ns) in common organic solvents and have demonstrated remarkable amplified spontaneous emission with a gain efficiency of > 10.
Anomaly Detection for Resilient Control Systems Using Fuzzy-Neural Data Fusion Engine (2011)

Resilient control systems in critical infrastructures require increased cyber-security and state-awareness. One of the necessary conditions for achieving the desired high level of resiliency is timely reporting and understanding of the status and behavioral trends of the control system. This paper describes the design and development of a neural-network based data-fusion system for increased state-awareness of resilient control systems. The proposed system consists of a dedicated data-fusion engine for each component of the control system. Each data-fusion engine implements three-layered alarm system consisting of: (1) conventional threshold-based alarms, (2) anomalous behavior detector using self-organizing maps, and (3) prediction error based alarms using neural network based signal forecasting. The proposed system was integrated with a model of the Idaho National Laboratory Hytest facility, which is a testing facility for hybrid energy systems. Experimental results demonstrate that the implemented data fusion system provides timely plant performance monitoring and cyber-state reporting.
Subsurface Oxygen on Pt(111) and Its Reactivity for CO Oxidation (2011)

Temperature has an important effect on the dissociative adsorption of molecular oxygen on platinum surfaces. Here, we show that if the substrate temperature is increased to 400–600 K, the total amount of oxygen loaded onto Pt(111) can be more than twice the well-established maximum coverage of 0.25 ML. While low energy electron diffraction and STM reveal a conventional p(2 × 2) structure of the topmost layer, temperature programmed desorption measurements indicate that additional oxygen is stored under the surface of platinum. Reactivity measurements show that this sub-surface oxygen layer does not lower the activity of such platinum surface towards CO oxidation. Therefore, while sub-surface oxygen layer does form under catalytically relevant temperatures on Pt(111), it has no great influence on the oxidizing ability of such surface. This sheds new light on the initial stages of platinum oxide formation, and may help bridge the understanding of catalytic oxidation of CO on Pt in ultra high vacuum and in high-pressure catalysis studies.
Material encapsulation and transport in core–shell micro/nanofibers, polymer and carbon nanotubes and micro/nanochannels (2007)

In this article, we review recent work on the co-electrospinning of polymer core–shell nanofibers and the manufacture of hollow nanotubes. The encapsulation and release of bioactive compounds from co-electrospun core–shell fibers is considered next, bearing in mind such applications as sensors and drug release. Then, nanofluidic phenomena in nanotubes made via co-electrospinning (as well as via the other processes) are discussed. We also consider dielectrophoresis in microchannels as a possible tool for the separation of viruses, nanoparticles and macromolecules.
Charge-transfer complexes in the scavenging by iodine of radicals formed on pulse radiolysis of <i>cyclo</i> hexane (1965)

Abstract Pulse radiolysis of solutions of iodine in cyclohexane resulted in the formation of a transient absorption with wavelength maximum at 3300 Å. This transient spectrum was assigned to the C6H12... I' charge-transfer complex. The spectrum and extinction coefficients of the complex over the wavelength range 2500 to 6500 Å were obtained, the coefficient at 3300 Å being 2025 1. mole-1 cm-1. Hydrogen iodide in cyclohexane gave rise to the same transient absorption. Pulse radiolysis of cyclohexane and cyclohexyl iodide alone gave rise to different transient spectra attributed to the cyclohexyl radical, absorbing in the ultraviolet, extinction coefficient 3401. mole-1 cm-1 at 2550 Å and the C6H11.. .I* charge-transfer complex, absorption maximum 3900 A, extinction coefficient ~ 103 to 104 1. mole-1 cm-1, respectively. During the course of the investigations rate constants were obtained for the following reactions: C6H11 + I2 C6H11I + I', kII = 7 x 109 1. mole-1 s-1, 2C6H12...I' -&gt; 2C6H12 + I2, kII = 1.06 x 1010 1. mole-1 s-1, or 21' -&gt; I2, aC6H10 + C6H12 2C6H11k11a+k11b=2.5 x 109 1. mole-1 s-1 bC12H22 Dilute solutions of iodine (10-4M) in cyclohexane yielded experimental evidence for neutral radical intermediates only. There were, however, indications that ionic radical intermediates occur in more concentrated solutions ( &gt; 10-3M). :
ChemInform Abstract: ISOUREA‐MEDIATED PREPARATION OF DEHYDRO AMINO ACIDS (1980)

Abstract Carbodiimide wie Diisopropylcarbodiimid (I) reagieren mit Alkoholen (II) zu den Isoharnstoffethern (III), die mit den geschützten Serinderivaten (IV) verestert und dann mit weiterem Carbodiimid zu den Alaninderivaten (VI) dehydratisiert werden.
Comparison of Chronic Neutral Endopeptidase Inhibition and Furosemide in an Ovine Model of Heart Failure (1996)

The hemodynamic, hormonal, and metabolic effects of chronic neutral endopeptidase (NEP) 24.11 inhibition and furosemide were compared in the pacing model of ovine heart failure (HF). Intravenous SCH 39370 induced a dose-related inhibition of NEP activity during 4-days treatment, in association with a transient increase in plasma atrial natriuretic peptide (ANP) and, at the higher dose, an increased mean level of plasma cyclic guanosine monophosphate. There was a significant and persistent decrease in left atrial pressure, a brief increase in cardiac output (CO), and a tendency for arterial pressure to be reduced. Significant dose-related diuresis and natriuresis were also observed. Furosemide induced a similar hemodynamic response, associated with greater diuresis and natriuresis. Both agents significantly reduced plasma aldosterone levels. Coinfusion of captopril on day 4 of treatment resulted in similar responses in both the SCH 39370- and furosemide pretreated groups. Chronic NEP inhibition significantly alters circulatory and renal function and appears to be as effective as furosemide in reducing cardiac preload in this model of congestive HF.
On hash-coding algorithms for partial-match retrieval (1974)

We examine the efficiency of generalized hash-coding algorithms for performing partial-match searches of a random-access file of binary words. A precise characterization is given of those hash functions which minimize the average number of buckets examined for a search; and a new class of combinatorial designs is introduced which permits the construction of hash functions with worst-case behavior approaching the best achievable average behavior in many cases.
Comparison of Nanotube Structures Constructed from α-, β-, and γ-Cyclodextrins by Potential-Controlled Adsorption (2003)

"Nanotube" structures of the alpha-, beta-, and gamma-cyclodextrins (CyD's), which are similar to that of CyD-polyrotaxane, were constructed by potential-controlled adsorption onto Au(111) surfaces in sodium perchlorate solution without a threaded polymer. CyD molecules adsorbed randomly on bare Au(111) surfaces without potential control and the desorption of CyD's from Au surfaces was observed at a negative potential of less than -0.60 V versus SCE. On the other hand, in the specific range between these potentials, ordered molecular arrays with "nanotube" structures of the CyD's (alpha-, beta-, and gamma-CyD) were observed on Au(111). The range of potentials for formation of the "nanotube" structures of alpha-, beta-, and gamma-CyD was from -0.15 to -0.20 V, from -0.25 to -0.45 V, and from -0.22 to -0.45 V, respectively. beta- and gamma-CyD require a more negative potential for adsorption-induced self-organization (AISO) than alpha-CyD in order to weaken adsorption and induce self-organization. Furthermore, we have succeeded in the visualization of the dynamic process in solution, such as the self-ordering, and the destruction of the nanotube structure. These results indicate that control of the electrode potential facilitates management of the delicate balance of various interactions, resulting in the formation of two-dimensional supramolecular structures on the substrates.
Maclean's model of flux penetration: addressing stability (2003)

The engineering design of eddy current actuated systems is expensive because of the rapid changes in field quantities and the resulting need to model very accurately. Many suggestions have been made to avoid computations in eddy current regions. The best known of these is the impedance boundary condition at steel interfaces. However, the impedance boundary condition does not work for nonlinear steel because the phasor analysis on which the impedance boundary condition is based is not applicable. MacLean's model is best suited for analyzing in the nonlinear region. Reported problems with time stepping are overcome by studying various time-stepping methods and identifying a suitable numerical scheme. The identified method is shown to be convergent by using the von Neumann stability test.