gebhart/patrepeval huggingface dataset:
MODELING AND OPTIMIZATION OF SURFACEROUGHNESS IN END MILLING OFALUMINIUM USING LEAST SQUAREAPPROXIMATION METHOD AND RESPONSESURFACE METHODOLOGY (2018)

In end milling, accurate setting of process parameters is extremely important to
obtained enhanced surface roughness (SR). Due to a recent innovation in
mechanization made it possible to produce high quality manufacturing products. The
perceptions of quality in mechanical products are their physical look that is the
surface roughness (SR). The aim of this research work is to develop mathematical
expression (M.E) and mathematical model using least square approximation method
and Response Surface Methodology (RMS) to predict the SR for end milling of Al 6061
alloy. The process parameters that were selected as predictors for the SR are Spindle
speed (V), axial depth of cut (a), feed rate (f) and radial depth of cut (d). 30 samples of
Al 6061 alloy were carried out using SIEG 3/10/0010 CNC machines and each of the
experimental result was measured using Mitutoyo surface roughness tester and Presso-
firm. The minimum SR of 0.5 μm were obtained at a spindle speed of 2034.608 rpm,
feed rate of 100 mm/min, axial depth of cut of 20 mm, and radial depth of cut 1.5 mm.
Analysis of variances shows that the most influential parameters was feed rate. After
ChemInform Abstract: Charge Storage States in Polyenes. (1994)

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.
The Wavelength-Shifting Optical Module in Application to the IceCube Neutrino Observatory (2023)

The Wavelength-shifting Optical Module (WOM) is a novel photosensor concept developed as part of the upcoming Upgrade for the IceCube Neutrino Observatory. It uses the technique of wavelength shifting and total internal reflection to increase the photon light yield in the UV-regime of the Cherenkov spectrum. The decoupling of the effective area from the size of light sensors enhances the signal-to-noise-ratio. Twelve WOM modules will be deployed in the IceCube Upgrade to increase the photon detection efficiency and thus enhance future low-energy analyses. The general concept can also be applied at the future IceCube-Gen2 detector, where passive light collecting extensions to the optical sensor modules locally increase the light collection efficiency. This technique would benefit the detection of supernova neutrinos or other particles with low light emissions. We report on new results in characterizing and optimizing the WOM concept, the production status of the modules to be deployed in 2025/26 as well as possible applications of the concept for IceCube-Gen2.
Discrete shearlet transform: faithful digitization concept and its applications (2011)

Over the past years, various representation systems which sparsely approximate functions governed by anisotropic features such as edges in images have been proposed. Alongside the theoretical development of these systems, algorithmic realizations of the associated transforms were provided. However, one of the most common short-comings of these frameworks is the lack of providing a unified treatment of the continuum and digital world, i.e., allowing a digital theory to be a natural digitization of the continuum theory. Shearlets were introduced as means to sparsely encode anisotropic singularities of multivariate data while providing a unified treatment of the continuous and digital realm. In this paper, we introduce a discrete framework which allows a faithful digitization of the continuum domain shearlet transform based on compactly supported shearlets. Finally, we show numerical experiments demonstrating the potential of the discrete shearlet transform in several image processing applications.
Stress–strain state in <i>α</i>-Ga<sub>2</sub>O<sub>3</sub> epitaxial films on <i>α</i>-Al<sub>2</sub>O<sub>3</sub> substrates (2020)

We consider the stress–strain state in α-Ga2O3/α-Al2O3 heterostructures, in which both constituting phases belong to trigonal crystal system. We utilize the hexagonal geometry (hexagonal cell) to account for structural features of the materials and include in the analysis the complete set of six elastic constants Cij being typical for materials with rhombohedral crystal structure that differs from materials with hexagonal one by the presence of an additional constant C14. This allows us to derive analytical formulas for elastic strains and mechanical stresses in pseudomorphic α-Ga2O3 films on α-Al2O3 substrates with various growth orientations assuming nonzero constant C14.
Nano-spectroscopy of excitons in atomically thin transition metal dichalcogenides (2022)

Excitons play a dominant role in the optoelectronic properties of atomically thin van der Waals (vdW) semiconductors. These excitons are amenable to on-demand engineering with diverse control knobs, including dielectric screening, interlayer hybridization, and moiré potentials. However, external stimuli frequently yield heterogeneous excitonic responses at the nano- and meso-scales, making their spatial characterization with conventional diffraction-limited optics a formidable task. Here, we use a scattering-type scanning near-field optical microscope (s-SNOM) to acquire exciton spectra in atomically thin transition metal dichalcogenide microcrystals with previously unattainable 20 nm resolution. Our nano-optical data revealed material- and stacking-dependent exciton spectra of MoSe<sub>2</sub>, WSe<sub>2</sub>, and their heterostructures. Furthermore, we extracted the complex dielectric function of these prototypical vdW semiconductors. s-SNOM hyperspectral images uncovered how the dielectric screening modifies excitons at length scales as short as few nanometers. This work paves the way towards understanding and manipulation of excitons in atomically thin layers at the nanoscale.
Solvothermal Synthesis and Electrochemical Properties of LiMnPO4 and Its Carbon Composite (2014)

The olivine-type LiMnPO4 was synthesized from LiH2PO4 and Mn(CH3COO)2·4H2O by a solvothermal method at several heating temperatures for 90–180°C. The XRD and SEM results indicated that the obtained LiMnPO4 samples consisted of a single phase with nano sized tabular particles. The prepared LiMnPO4 and acetylene black as a carbon source were ball-milled for preparing carbon/LiMnPO4 composite (LiMnPO4/C) samples. The milled LiMnPO4/C sample heated at 120°C showed the highest first discharge capacity of 147 mAh g−1 with excellent cycleability at a 0.1C rate (CC-CV mode) and 25°C. It was found that the electrochemical properties of LiMnPO4 were significantly enhanced by ball milling with a conductive carbon.
Sub‐10 nm Graphene Nanoribbon Array Field‐Effect Transistors Fabricated by Block Copolymer Lithography (2013)

Sub-10 nm Graphene Nanoribbon Arrays are fabricated over large areas by etching CVD-grown graphene. A mask is used made by the directed self-assembly of a cylindrical PS-b-PDMS block copolymer under solvent annealing guided by a removable template. The optimized solvent annealing process, surface-modified removable polymeric templates, and high Flory-Huggins interaction parameters of the block copolymer enable a highly aligned array of nanoribbons with low line edge roughness to be formed. This leads to a higher on/off ratio and stronger temperature dependence of the current for nanoribbon FETs, and a photocurrent which is 30 times larger compared to unpatterned graphene.
Measuring the spatial extent of individual localized photonic states (2012)

We measure the spatial extent of individual photonic states that are localized by residual disorder in a slow-light photonic crystal waveguide. The size of the states is measured by locally perturbing them individually through an electromagnetic interaction with a near-field probe. We identify localized states that are not observed in transmission and show that they are shorter than the waveguide length. We also obtain near-field measurements of the participation ratio, from which the size of the states is also derived, in quantitative agreement with the size measured with the perturbation method.
Long-range surface plasmon-polariton waveguides and devices in lithium niobate (2007)

Long-range surface plasmon-polariton waveguides and devices based on a thin narrow Au stripe buried in z-cut LiNbO3 claddings and designed for operation at free-space optical wavelengths near 1550nm are described and discussed. Parallel or antiparallel crystal orientations for the claddings lead to phase modulation or intensity modulation via mode cutoff, respectively. Theoretical results are given for straight waveguides, curved waveguides, and Bragg gratings in symmetric claddings, and for straight waveguides in electro-optically induced asymmetric claddings. The main theoretical findings are that 1dB∕mm of attenuation (or less) is achievable using Au stripes of reasonable dimensions (0.5–1μm wide, 20–40nm thick), that low overlap losses (&amp;lt;1dB) to large and small modes are achievable for the same stripe thickness, that radii of curvature in the range of 10–30mm are required for stripes having a moderate (10−3) confinement, that first order gratings having a reflectance of 0.9 and a bandwidth of 0.75nm are achievable and that they are electro-optically tunable over a 2.9nm range, and that an electro-optically induced index asymmetry of about 4×10−4 is sufficient to cut off weakly (10−4) confined modes. Structures were fabricated by direct wafer bonding and thinning to form the lithium niobate claddings. The measured optical insertion loss of 2mm long waveguides varied from 10to17dB, which are somewhat higher than theoretical expectations. Low frequency electro-optic mode cutoff measurements produced extinction ratios near 12dB and a linear transfer characteristic, thus demonstrating intensity modulation via this mechanism. The results suggest that bulk values for the optical and electro-optic properties of the LiNbO3 claddings have been retained.
The tethered Biginelli condensation in natural product synthesis (2004)

This review describes the development of the tethered Biginelli condensation and its application to the total synthesis of structurally complex, bioactive guanidine alkaloids.
ChemInform Abstract: ASYMMETRIC REDUCTIONS WITH A CHIRAL 1,4‐DIHYDROPYRIDINE CROWN ETHER (1979)

Abstract Die Titelreaktion ist Bestandteil eines katalytischen Kreislaufs, bei dem ein chiraler Crownether, der in einem Teilbereich 1,4‐Dihydropyridin enthält, einen Metallkomplex bildet, in dem wiederum das eingeschlossene Metall über einen intermediären ternären Komplex Carbonylverbindungen reduzieren kann.
Direct Binding of Specific AUF1 Isoforms to Tandem Zinc Finger Domains of Tristetraprolin (TTP) Family Proteins (2011)

Tristetraprolin (TTP) is the prototype of a family of CCCH tandem zinc finger proteins that can bind to AU-rich elements in mRNAs and promote their decay. TTP binds to mRNA through its central tandem zinc finger domain; it then promotes mRNA deadenylation, considered to be the rate-limiting step in eukaryotic mRNA decay. We found that TTP and its related family members could bind to certain isoforms of another AU-rich element-binding protein, HNRNPD/AUF1, as well as a related protein, laAUF1. The interaction domain within AUF1p45 appeared to be a C-terminal "GY" region, and the interaction domain within TTP was the tandem zinc finger domain. Surprisingly, binding of AUF1p45 to TTP occurred even with TTP mutants that lacked RNA binding activity. In cell extracts, binding of AUF1p45 to TTP potentiated TTP binding to ARE-containing RNA probes, as determined by RNA gel shift assays; AUF1p45 did not bind to the RNA probes under these conditions. Using purified, recombinant proteins and a synthetic RNA target in FRET assays, we demonstrated that AUF1p45, but not AUF1p37, increased TTP binding affinity for RNA ∼5-fold. These data suggest that certain isoforms of AUF1 can serve as "co-activators" of TTP family protein binding to RNA. The results raise interesting questions about the ability of AUF1 isoforms to regulate the mRNA binding and decay-promoting activities of TTP and its family members as well as the ability of AUF1 proteins to serve as possible physical links between TTP and other mRNA decay proteins and structures.
Low-loss and Small-cross-section Waveguide for Compact Terahertz Free -electron Laser (2021)

The demand for terahertz (THz) sources that can be used in practical implementations has not yet been fully met. Through the development of small-scale free-electron lasers (FEL), we investigated a solution to overcome the low lasing gain of the FEL, which is caused by a small-current accelerator and a short-length undulator. To enhance the FEL gain, the FEL interaction between the electron beam and radiation was increased by reducing the cross-sectional area of the FEL oscillator mode. We developed a waveguide for the FEL oscillator, which has a remarkably small eye-shaped cross section with low wave loss. The mode cross-sectional area was calculated to be just 4 mm2 (full width at half maximum), which is considerably smaller than those of the free-space Gaussian mode and other waveguide modes. Using COMSOL Multiphysics simulation code, we calculated and analyzed the attenuation loss and mode cross-section area for waveguides of different shapes and sizes, and we observed that the dielectric coated eye-shaped waveguide has the lowest attenuation loss, that is, less than 2.5&#x0025; for 1-m propagation at an operating wavelength of 300&#x2013;600 &#x00B5;m. These results are in good agreement with our requirements for the tabletop THz FEL. Finally, we showed that the calculated operating wavelength range of the waveguide-mode THz FEL is 300&#x2013;600 &#x00B5;m using the machine parameters of an accelerator and undulator that were developed by considering the dispersion relations of the eye-shaped waveguide and undulator radiation.
Quantification of Ammonia Emissions With High Spatial Resolution Thermal Infrared Observations From the Hyperspectral Thermal Emission Spectrometer (HyTES) Airborne Instrument (2019)

Thermal infrared spectra can provide unique information on atmospheric ammonia enhancements, including those produced by agricultural, industrial, and biomass burning sources. In this work, we develop and test a quantitative ammonia retrieval algorithm using data from the airborne hyperspectral thermal emission spectrometer (HyTES) instrument over diverse targets, including persistent ammonia sources, such as cattle feedlots and a power plant, as well as a small, smoldering wildfire. Although no formal validation was possible due to lack of collocated observations, the HyTES ammonia values over feedlots in the California San Joaquin Valley are shown to be consistent within the estimated retrieval uncertainty of $\sim$20%-50% with insitu ammonia values collected over the same facilities during the 2013 DISCOVER-AQ field campaign. HyTES also observed meter-scale thermal hot spots associated with a small wildfire in Northern Arizona, which was determined to coincide with the emission of free ammonia, presumed to originate from the fire. This very localized emission source, not visible from satellite sensors, could be resolved in HyTES imagery. The ammonia enhancement immediately downwind from the smoldering fire, before the free ammonia reacted to form aerosols, was found to be distinguishable from the background with values three to ten times smaller than ammonia enhancements from the power plant and cattle feedlots, respectively. High-resolution detection and quantification of ammonia over nonpersistent sources like wildfires from HyTES shows that it is a powerful tool that can be used to improve regional scale fire emission inventories by accounting for the presence of temporally short ammonia processes.
Identification and CRISPR/Cas9 Inactivation of the C1s Protease Responsible for Proteolysis of Recombinant Proteins Produced in CHO Cells (2019)

Proteolysis associated with recombinant protein expression in Chinese Hamster Ovary (CHO) cells has hindered the development of biologics including HIV vaccines. When expressed in CHO cells, the recombinant HIV envelope protein, gp120, undergoes proteolytic clipping by a serine protease at a key epitope recognized by neutralizing antibodies. The problem is particularly acute for envelope proteins from clade B viruses that represent the major genetic subtype circulating in much of the developed world, including the US and Europe. In this paper, we have identified complement Component 1's (C1s), a serine protease from the complement cascade, as the protease responsible for the proteolysis of gp120 in CHO cells. CRISPR/Cas9 knockout of the C1s protease in a CHO cell line was shown to eliminate the proteolytic activity against the recombinantly expressed gp120. In addition, the C1s<sup>-/-</sup> MGAT1<sup>-</sup> CHO cell line, with the C1s protease and the MGAT1 glycosyltransferase knocked out, enabled the production of unclipped gp120 from a clade B isolate (BaL-rgp120) and enriched for mannose-5 glycans on gp120 that are required for the binding of multiple broadly neutralizing monoclonal antibodies (bN-mAbs). The availability of this technology will allow for the scale-up and testing of multiple vaccine concepts in regions of the world where clade B viruses are in circulation. Furthermore, the proteolysis issues caused by the C1s protease suggests a broader need for a C1s-deficient CHO cell line to express other recombinant proteins that are susceptible to serine protease activity in CHO cells. Similarly, the workflow described here to identify and knockout C1s in a CHO cell line can be applied to remedy the proteolysis of biologics by other CHO proteases.
Efficient synthesis of 1,2,4‐dithiazolidine‐3,5‐diones (dithiasuccinoyl‐amines) and observations on formation of 1,2,4‐thiadiazolidine‐3,5‐diones by related chemistry (1984)

Abstract An efficient synthesis of 1,2,4‐dithiazolidine‐3,5‐diones ( 1 ) from chlorocarbonylsulfenyl chloride ( 3 ) plus O ‐dimethylaminoethyl‐ N ‐alkyl or aryl thiocarbamates ( 4 ) has been worked out. In this synthesis, 1,2,4‐thiadiazolidine‐3,5‐diones ( 5 ) have been shown to arise as low‐level by‐products, and experiments were conducted to elucidate the mechanism of the side reaction. N,N ′‐Dimethyl‐1,2,4‐thiadiazolidine‐3,5‐dione ( 5a ) was prepared in one step from N,N ′‐dimethylurea plus 3 , or from 4a plus one equivalent of sulfuryl chloride. A general route to 5 involved reaction of equimolar amounts of isocyanates ( 6 ), isothiocyanates ( 7 ) and sulfuryl chloride followed by hydrolysis of intermediate 9 . Heterocycles reported have been characterized by nmr, ir, uv, ms, and hplc.
Fibrinolytic, antithrombotic, and antiplatelet drugs in acute coronary syndromes (2018)

Antithrombotic therapy is a major cornerstone in the treatment for acute coronary syndromes, as thrombus formation upon a plaque rupture or an erosion plays a pivotal role in non-ST-segment elevation as well as ST-segment elevation acute coronary syndromes. Both acute and long-term oral antiplatelet therapies, targeting specific platelet activation pathways, have demonstrated significant short- and long-term benefits. The use of anticoagulants is currently largely confined to the acute setting, except in patients with a clear indication for long-term treatment, including atrial fibrillation or the presence of intraventricular thrombi. Despite the benefit of primary percutaneous coronary intervention in ST-segment elevation myocardial infarction, fibrinolysis continues to play an important role throughout the world as well. In this chapter, the fibrinolytic, antiplatelet, and anticoagulant agents used in the management of acute coronary syndrome patients are discussed.
Arabidopsis has a cytosolic fumarase required for the massive allocation of photosynthate into fumaric acid and for rapid plant growth on high nitrogen (2010)

The Arabidopsis genome has two fumarase genes, one of which encodes a protein with mitochondrial targeting information (FUM1) while the other (FUM2) does not. We show that a FUM1-green fluorescent protein fusion is directed to mitochondria while FUM2-red fluorescent protein remains in the cytosol. While mitochondrial FUM1 is an essential gene, cytosolic FUM2 is not required for plant growth. However FUM2 is required for the massive accumulation of carbon into fumarate that occurs in Arabidopsis leaves during the day. In fum2 knock-out mutants, fumarate levels remain low while malate increases, and these changes can be reversed with a FUM2 transgene. The fum2 mutant has lower levels of many amino acids in leaves during the day compared with the wild type, but higher levels at night, consistent with a link between fumarate and amino acid metabolism. To further test this relationship we grew plants in the absence or presence of nitrogen fertilizer. The amount of fumarate in leaves increased several fold in response to nitrogen in wild-type plants, but not in fum2. Malate increased to a small extent in the wild type but to a greater extent in fum2. Growth of fum2 plants was similar to that of the wild type in low nitrogen but much slower in the presence of high nitrogen. Activities of key enzymes of nitrogen assimilation were similar in both genotypes. We conclude that FUM2 is required for the accumulation of fumarate in leaves, which is in turn required for rapid nitrogen assimilation and growth on high nitrogen.
Chiral-at-<i>ansa</i>-Bridged Group 4 Metallocene Complexes {(R<sup>1</sup>R<sup>2</sup>C)-(3,6-<i>t</i>Bu<sub>2</sub>Flu)(3-R<sup>3</sup>-5-Me-C<sub>5</sub>H<sub>2</sub>)}MCl<sub>2</sub>: Synthesis, Structure, Stereochemistry, and Use in Highly Isoselective Propylene Polymerization (2010)

New chiral racemic, sterically crowded fluorenyl-cyclopentadienyl compounds having monoaryl-substituted methylene bridges (R1R2C)-((3,6-tBu2Flu)H)(3-R3-5-Me-C5H3) (R1 = H, R2 = Ph, R3 = tBu: 2a; R1 = H, R2 = 2,4,6-Me3C6H2 (Mes); R3 = CMe2Ph (cumyl): 2b; R1 = H, R2 = 3,5-(CF3)2C6H3, R3 = tBu: 2c) or a disubstituted (R1 = CF3, R2 = Ph, R3 = tBu: 2d) as well as an unsubstituted (nonstereogenic) methylene bridge (R1 = R2 = H, R3 = tBu: 2e) were synthesized via nucleophilic additions to substituted fulvenes. The zirconium and hafnium dichloro complexes derived from proligands 2a, 2b, and 2e, namely, {Ph(H)C-(3,6-tBu2Flu)(3-tBu-5-Me-C5H2)}ZrCl2 (3a), {Ph(H)C-(3,6-tBu2Flu)(3-tBu-5-Me-C5H2)}HfCl2 (4a), {Mes(H)C-(3,6-tBu2Flu)(3-cumyl-5-Me-C5H2)}ZrCl2 (3b), and {H2C-(3,6-tBu2-Flu)(3-tBu-5-Me-C5H2)}ZrCl2 (3e), were prepared (63−88% yields). Attempted metalations at the fluorinated proligands 2c and 2d were not successful. Due to the presence of the stereogenic center of the ansa-bridge, 3a, 4a, and 3b exist as mixtures of two diastereomers in which the most bulky substituent in the methylene bridge is either anti (major product in the case of 3a and 4a) or syn (only one observed for 3b) to the 5-methyl substituent in the Cp ring. Diastereomerically pure anti-3a, anti-4a and syn-4a, and syn-3b were isolated and characterized by elemental analysis, NMR spectroscopy, and X-ray crystallography. When activated with MAO, metallocene complex anti-3a showed very high activity in the polymerization of propylene (14 000 kg(PP)·mol(Zr)−1·h−1, toluene, 60 °C) to yield highly isotactic polypropylene (iPP) with [m]4 = 95.8% and Tm = 153 °C. Both diastereomers of hafnium analogues exhibited lower activities (260−270 kg(PP) mol(Hf)−1·h−1) but distinct catalytic behavior: anti-4a yielded low molecular weight and moderately isotactic PP ([m]4 = 88.8%), while highly isotactic PP ([m]4 = 94.0%) with a bimodal distribution was produced with syn-4a. Precursor syn-3b was inactive under standard polymerization conditions, presumably due to deactivation of the cationic metal center by the cumyl Cp substituent. Methylene-bridged 3e produced highly isotactic PP ([m]4 = 96.9%; Tm = 154 °C) with moderate activity (2 320 kg(PP)·mol(Zr)−1·h−1).
Introduction (2012)

This chapter contains sections titled: Scope of the Book Outline Notation