gebhart/patrepeval huggingface dataset:
Immobilized catalysts. XIV. Influence of sysnthesis conditions on fixation of copper complexes (1986)

The influence of conditions of the reaction (concentration relationships, reaction temperature) of the polymeric carrier PE-grafted-poly(acrylic acid) with Cu(OCOCH/sub 3/)/sub 2/ on the amount of Cu(II) bound and the structure of the immobilized complexes was studied. The ''concentration'' dependence is Langmuirian in character and its analysis leads to the evaluation of the stability constant of Cu(II) complexes, equal to 300 liters/mole at 333 degrees K. The constant corresponding to the limiting binding of Cu(II) is equal to 0.35 mole/mole (22.22 mg of Cu(II)/g). By using the labeled atoms technique, a stepwise mechanism of fixation of Cu(II) was shown: binding by means of one (up to 16 mole% with respect to fixated Cu(II), k/sub 1/ = 16.10/sup -//sub 2/ mole/g) and two (k/sub 2/ = 2.54.10/sup -//sub 3/ mole/g) carboxyl groups of the grafted fragments. In the PE-gr-PAA-Cu(II) systems the conditions, viz., an insoluble polymeric substrate - a soluble polymeric functional coating, are modeled, whence the advantages of soluble and three-dimensional cross-linked polymers are shown.
Effects of metal and ring reduction on metallo(octaethylisobacteriochlorins). Resonance Raman spectra of the nickel(I), copper(I), and zinc(II) radical anion complexes (1993)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTEffects of metal and ring reduction on metallo(octaethylisobacteriochlorins). Resonance Raman spectra of the nickel(I), copper(I), and zinc(II) radical anion complexesAlexander D. Procyk, Alan M. Stolzenberg, and David F. BocianCite this: Inorg. Chem. 1993, 32, 5, 627–633Publication Date (Print):March 1, 1993Publication History Published online1 May 2002Published inissue 1 March 1993https://pubs.acs.org/doi/10.1021/ic00057a023https://doi.org/10.1021/ic00057a023research-articleACS PublicationsRequest reuse permissionsArticle Views64Altmetric-Citations8LEARN 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-Alertsclose Get e-Alerts
Reductions of esters, acyl halides, alkyl halides, and sulfonate esters with sodium borohydride in polyethylene glycols: scope and limitation of the reaction (1983)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTReductions of esters, acyl halides, alkyl halides, and sulfonate esters with sodium borohydride in polyethylene glycols: scope and limitation of the reactionEnzo Santaniello, Alberto Fiecchi, Ada Manzocchi, and Patrizia FerraboschiCite this: J. Org. Chem. 1983, 48, 18, 3074–3077Publication Date (Print):September 1, 1983Publication History Published online1 May 2002Published inissue 1 September 1983https://pubs.acs.org/doi/10.1021/jo00166a029https://doi.org/10.1021/jo00166a029research-articleACS PublicationsRequest reuse permissionsArticle Views1776Altmetric-Citations40LEARN 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-Alertsclose Get e-Alerts
TWIP and Fracture Behavior in the Superalloy 625 at Room and Cryogenic Temperatures (2019)

In this study an austenitic nickel base alloy (Alloy 625) with medium to high stacking fault energy was tensile tested at room temperature and at cryogenic temperature, -196°C, to investigate if twinning was involved in the fracture process. Fracture surfaces and microstructure were characterized using scanning electron microscopy and texture was evaluated with scanning electron microscopy-electron backscatter diffraction at three positions along the tensile test specimens. Features where investigated with electron channelling contrast imaging. At room temperature the predominant deformation mechanism is slip and at cryogenic temperature slip is followed by deformation twinning. At room temperature deformation twinning will make an extra deformation contribution in the localized necking region compared to the cryogenic temperature case where deformation twins already are distributed in the microstructure and in this case will hinder the dislocations to move freely and instead cause stress field build up at the twin boundaries and subsequent microcrack and void formation.
Studies on the Alkaloids of Menispermaceous Plants. CLVII (1957)

Hey and Lobs recently synthesized dl-1, 2-methylenedioxy-9-methoxy-10-hydroxy-aporphine (III) and reported that the free base is an unstable substance melting at 126-129°. Reëxamination of this reaction revealed that the pure substance of (III) came in crystals of m. p. 209-210° and it was assumed that (III) obtained by Hey and Lobs is an impure substance. Comparison of ultraviolet and infrared absorption spectra of (III) obtained here with l-phanostenine, m. p. 210°, the alkaloid of Stephania Sasakii HAYATA, showed them to be identical. It follows, therefore, that the structure of l-phanostenine would be represented by (III).
Time-dependent density functional theory study on the coexistent intermolecular hydrogen-bonding and dihydrogen-bonding of the phenol-H2O-diethylmethylsilane complex in electronic excited states (2010)

An intermolecular coexistent hydrogen bond and a dihydrogen bond of a novel phenol-H(2)O-diethylmethylsilane (DEMS) complex in the electronically excited states were studied using the time-dependent density functional theory (TDDFT) method. Frontier molecular orbitals analysis revealed that the S(2) state of the dihydrogen-bonded phenol-H(2)O-DEMS complex is a locally excited state in which only the phenol site is electronically excited. Upon electronic excitation, the O-H and H-Si vibrational modes are red shifted compared with those calculated for the ground state. The O-H and H-Si bonds involved in the dihydrogen bond O-H...H-Si and hydrogen bond O-H...O are longer in the S(2) state than in the ground state. The H...H and H...O distances significantly shorten in the S(2) state. Thus, both the intermolecular dihydrogen bond and the hydrogen bond of the phenol-H(2)O-DEMS complex are stronger in the electronically excited state than in the ground state. In addition, the hydrogen bonding is favorable for the formation of the intermolecular dihydrogen bond in the ground state. However, they are competitive with each other in the electronically excited state.
Serviceability of Coiled Tubing for Sour Oil and Gas Wells (1997)

Serviceability of Coiled Tubing for Sour Oil and Gas Wells M.S. Cayard; M.S. Cayard CLI International, Inc. Search for other works by this author on: This Site Google Scholar R.D. Kane R.D. Kane CLI International, Inc. Search for other works by this author on: This Site Google Scholar Paper presented at the SPE/ICoTA North American Coiled Tubing Roundtable, Montgomery, Texas, April 1997. Paper Number: SPE-38410-MS https://doi.org/10.2118/38410-MS Published: April 01 1997 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Get Permissions Search Site Citation Cayard, M.S., and R.D. Kane. "Serviceability of Coiled Tubing for Sour Oil and Gas Wells." Paper presented at the SPE/ICoTA North American Coiled Tubing Roundtable, Montgomery, Texas, April 1997. doi: https://doi.org/10.2118/38410-MS Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAll ProceedingsSociety of Petroleum Engineers (SPE)SPE/ICoTA Well Intervention Conference and Exhibition Search Advanced Search AbstractCoiled tubing is an extremely useful tool in many well logging and workover applications in oil and gas production operations. Several important concerns regarding its use include the need for improved guidelines for the assessment of mechanical integrity, fatigue damage, and the effects of hydrogen sulfide in sour oil and gas production environments. This paper provides information regarding the use of coiled tubing in sour environments with particular emphasis on sulfide stress cracking, hydrogen induced cracking and stress-oriented hydrogen induced cracking and how they work synergistically with cyclic cold working of the steel tubing. Keywords: production monitoring, Completion Installation and Operations, Corrosion Management, Workplace Hazard, Reservoir Surveillance, Coiled tubing operations, serviceability, production control, Production Chemistry, H2S management Subjects: Well & Reservoir Surveillance and Monitoring, Production Chemistry, Metallurgy and Biology, Health, Noise, chemicals, and other workplace hazards, Completion Installation and Operations, Coiled tubing operations, Corrosion inhibition and management (including H2S and CO2) This content is only available via PDF. 1997. Society of Petroleum Engineers You can access this article if you purchase or spend a download.
Hyper-geodesic structures: excerpts from a visual catalog. (1994)

A class of hyper-geodesic surface structures is presented. The surfaces of known polygons, polyhedra, plane and space tessellations, higher dimensional polytopes can be subdivided into parallelograms. The subdivisions are portions of non-periodic tilings having edges parallel to an n-star, a star of n vectors, and are projections from n-dimensional space. The tilings are used to subdivide regular polygons or their fundamental regions, and the subdivided polygons are then used as faces of all regular polytopes. A repertory of plane-faced and curved space structures derived this way is shown in a visual catalog. The derived structures are alternatives to the well known geodesic surface structures used in architecture.
Simulated-annealing real-space refinement as a tool in model building (2002)

Methods have been developed that further automate the building of macromolecular structures into electron-density maps. The software supports molecular-dynamics real-space refinement of an atomic model to local regions of a map within the context of a popular molecular-modeling program, O [Jones et al. (1991), Acta Cryst. A47, 110-119]. It is implemented as a module to the CNS refinement package [Brünger et al. (1998), Acta Cryst. D54, 905-921], controlled by a graphical user interface and commands executed directly through the molecular-graphics package. The method is illustrated with examples of the building and rebuilding of protein and nucleic acid models in which laborious manual adjustments are avoided. The resulting models show improved convergence during subsequent reciprocal-space refinement. The novel feature of the RSRef2000 software is the combination of simulated-annealing optimization with local real-space refinement, allowing several local minima to be explored quickly and automatically within the context of interactive model building.
Transmission performance improvement in digital coherent system by suppressing cycle slip using statistical analysis algorithm (2013)

Cycle slip adversely affects transmission performance in digital coherent systems. Proposed is an algorithm using statistical analysis for suppressing cycle slip in a digital coherent system. The cycle slip suppression effect, transmission performance, and nonlinear tolerance of the proposed algorithm were numerically investigated. The proposed algorithm enables cycle‐slip‐free wavelength division multiplex transmission under the presence of nonlinear optical effect and improves transmission performance.
Nonlinearity and disorder in two-dimensional fiber arrays (2003)

We experimentally observe diffusive wave propagation in disordered two-dimensional arrays of interacting optical fibers. A weak Kerr nonlinearity can cause an increased mobility, where strong nonlinearity leads to the formation of discrete solitons.
Oral Ingestion and Intraventricular Injection of Curcumin Attenuates the Effort-Related Effects of the VMAT-2 Inhibitor Tetrabenazine: Implications for Motivational Symptoms of Depression (2017)

Effort-related choice tasks are used for studying depressive motivational symptoms such as anergia/fatigue. These studies investigated the ability of the dietary supplement curcumin to reverse the low-effort bias induced by the monoamine storage blocker tetrabenazine. Tetrabenazine shifted effort-related choice in rats, decreasing high-effort lever pressing but increasing chow intake. The effects of tetrabenazine were reversed by oral ingestion of curcumin (80.0-160.0 mg/kg) and infusions of curcumin into the cerebral ventricles (2.0-8.0 μg). Curcumin attenuates the effort-related effects of tetrabenazine in this model via actions on the brain, suggesting that curcumin may be useful for treating human motivational symptoms.
Carotid endarterectomy: to shunt or not to shunt. (1988)

Because of controversies in the cerebrovascular literature regarding the use of an intraluminal shunt in carotid endarterectomy, we report a randomized prospective study of 118 consecutive symptomatic patients receiving surgery within a single neurosurgical practice. Over 4 years, 138 carotid endarterectomies were performed in the 118 patients, 63 operations with intraluminal shunting and 75 without. Standard rationale for surgery included ipsilateral cerebral infarction in 38% of the operations and ipsilateral transient ischemic attacks in 36%. Unilateral angiographic stenosis of greater than 90% was seen in 58% of the operations; there were no ipsilateral occlusions. Surgery was performed under general anesthesia with barbiturate induction and mild blood pressure elevation. The 30-day complication rate included a mortality rate of 0.7% with a 5.1% incidence of postoperative neurologic deficit and a 1.4% rate of myocardial infarction. In the 24 hours after surgery there were no cerebral infarctions in the shunted group and six in the unshunted group. This 8% rate in the unshunted group compared with 0% in the shunted group was significant at p = 0.023 with a power of 0.95 by Fisher's exact test and chi 2 analysis. This suggests that in our neurosurgical practice (resident training program) the use of an intraluminal shunt during carotid endarterectomy significantly reduces the risk of intraoperative neurologic deficit without increasing the incidence of other complications.
Kosmotropic Salt Activation and Substrate Specificity of Poliovirus Protease 3C (2006)

Picornaviruses produce a large polyprotein, which is cleaved by virally encoded cysteine peptidases, picornain-2A and -3C. Picornain-3C has characteristics of both the serine peptidase chymotrypsin and the cysteine peptidase papain in that the 3D structure resembles chymotrypsin, but its nucleophile is a cysteine SH rather than a serine OH group. We investigated the specificity of poliovirus picornain-3C (PV3C) protease and the influence of kosmotropic salts on catalytic activity, using FRET peptides related to a cleavable segment of the virus polyprotein. The peptidase activity of PV3C was found to be 100-fold higher in the presence of 1.5 M sodium citrate. This activation was anion-dependent, following the Hofmeister series citrate(3-) > SO4(2-) > HPO4(2-) > acetate- > HCO3(-) > Cl-. The activation appeared to be independent of substrate sequence and arose primarily from an increase in kcat. A shift to higher pH was also observed for the pK1 of the enzyme pH-activity profile. Experiments with the fluorescent probe ANS (1-anilino-8-naphthalene sulfonate) showed that the protease bound the dye in the presence of 1 M sodium citrate but not in its absence or in the presence of 1 M NaCl. Structural changes in PV3C protease were detected using circular dichroism and the thermodynamic data indicated a more organized active site in the presence of sodium citrate. PV3C protease was also activated in D2O, which was added to the activation by citrate. These effects seem to be related to nonspecific interactions between the solvent and the protein. Our data show that the catalytic efficiency of PV3C protease is modulated by the composition of the environment and that this modulation may play a role in the optimal processing of polyprotein for the virus assembly that occurs inside specific vesicles formed in poliovirus-infected cells.
Radicals from One-Electron Oxidation of 4-Aminoresorcinol:  Models for the Active Site Radical Intermediate in Copper Amine Oxidases (2000)

Pulse radiolysis, laser flash photolysis, and time-resolved resonance Raman spectroscopy have been used to study radicals derived by one-electron oxidation of 4-aminoresorcinol as models for the active site free-radical intermediate in the catalytic cycle of copper amine oxidases containing the trihydroxyphenylalanine (TOPA) quinone cofactor. The 4-aminoresorcinol radical at neutral pH has an absorption maximum at 450 nm, which is similar to that of the enzyme radical. At pH 5 the resonance Raman spectrum of the radical from one-electron oxidation of 4-aminoresorcinol resembles that in the enzyme. The radical protonates at lower pH values with a pKa of 3.4 to give a species with a blue shifted absorption and different resonance Raman spectrum. Time-resolved resonance Raman spectroscopy shows that above pH 6.4 the radical from 4-aminoresorcinol deprotonates again to give a species that has a resonance Raman spectrum quite different from that of the enzyme radical. This second deprotonation is not immediately obvious from the transient absorption spectra obtained by pulse radiolysis. Interpretation of these spectra and comparison with related systems indicates that the enzyme intermediate is the singly deprotonated form of the radical. The results are discussed with respect to a recently proposed mechanism for the oxidative half reaction of copper amine oxidases (Su and Klinman, Biochemistry 1998, 37, 12513) in which the rate-limiting step is the oxidation by molecular oxygen of the fully reduced cofactor to the radical intermediate.
Scanning mass spectrometry probe for biochemical imaging (2006)

A novel ion source concept for sampling and ionising molecules for mass spectrometric analysis which is amenable for integration with an atomic force microscope is described. This combination enables simultaneous imaging of the topography of complex biological samples as well as their local biochemical make-up. The resulting scanning mass spectrometry probe has potential to become a new tool for spatially and temporally resolved, in-situ mass spectrometric analysis of biological tissues or even a single cell.
A Facile Synthesis of Carboxamides by Dehydration Condensation Between Free Carboxylic Acids and Amines Using O,O'-Di(2-pyridyl) Thiocarbonate as a Coupling Reagent (2000)

Carboxamides are prepared in high yields by dehydration condensation between nearly equimolar amounts of free carboxylic acids and amines both of which involve secondary or tertiary alkyl substituted ones with O , O' -di(2-pyridyl) thiocarbonate, a coupling reagent, in the presence of a catalytic amount of 4-(dimethylamino)pyridine.
The Decision to Remarry (1981)

Remarriage is an increasingly common phenomenon that affects millions of men, women and children. In this paper, the author presents a general profile of remarriage and the process by which divorced people decide to remarry. A format is described through which clinicians can evaluate critical issues that determine the readiness of divorced people to remarry. These issues are presented along with case illustrations that demonstrate various problems that can arise and their solutions in therapy for the divorced.
Universal properties for linelike melting of the vortex lattice (1999)

Using numerical results obtained within two models describing vortex matter [interacting elastic lines (Bose model) and uniformly frustrated $\mathrm{XY}$ model] we establish universal properties of the melting transition within the linelike regime. These properties, which are captured correctly by both models, include the scaling of the melting temperature with anisotropy and magnetic field, the effective line tension of vortices in the liquid regime, the latent heat, the entropy jump per entanglement length, and relative jump of Josephson energy at the transition as compared to the latent heat. The universal properties can serve as experimental fingerprints of the linelike regime of melting. Comparison of the models allows us to establish boundaries of the linelike regime in temperature and magnetic field.
Organocatalytic Asymmetric Diels–Alder Reactions of 3‐Vinylindoles (2008)

Diels or no Diels? A bifunctional organic catalyst based on the thiourea motif is able to coordinate both diene and dienophile in an unprecedented asymmetric Diels–Alder reaction of 3-vinylindole derivatives, giving a rapid access to optically active tetra- and hexahydrocarbazoles with excellent results in terms of yields, diastereoselectivities, and enantioselectivities. Detailed facts of importance to specialist readers are published as ”Supporting Information”. Such documents are peer-reviewed, but not copy-edited or typeset. They are made available as submitted by the authors. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
ChemInform Abstract: A Facile Synthesis of 7,8/6,7 Fused Pyrano[4,3‐b]pyridinochromones and Evaluation of Antibacterial Activity. (2001)

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.