gebhart/patrepeval huggingface dataset:
Catalyst Regeneration, FCC units (2000)

Abstract The fluid catalytic cracking (FCC) process is an important refinery process in the United States. Catalyst regeneration is an essential part of this process. In the reactor section of a FCC unit, hydrocarbon feed is combined with hot fluidizable cracking catalyst at the base of the riser reactor. Catalyst and hydrocarbon vapors pass up the riser in a dilute‐phase, plug‐type flow and discharge into the reactor vessel where catalyst and hydrocarbon vapors are separated. When in contact with the catalyst, the hydrocarbon feed cracks to form gasoline, middle distillates, liquefied petroleum gas (LPG), and fuel gas. Coke, which is also formed, deposits on the catalyst surface and greatly reduces the catalyst activity. To restore its activity, the catalyst passes into the regenerator section where the coke is burned off. The heat released from coke burning is completely used to provide the heat requirements on the reactor side. Heat balance, environmental concerns, regenerator configuration and design, and other parameters of FCC are discussed.
Optimal Dynamic Placement of Virtual Machines in Geographically Distributed Cloud Data Centers (2017)

In geo-distributed cloud systems, a key challenge faced by cloud providers is to optimally tune and configure the underlying cloud infrastructure. An important problem in this context, deals with finding an optimal virtual machine (VM) placement, minimizing costs, while at the same time, ensuring good system performance. Moreover, due to the fluctuations of demand and traffic patterns, it is crucial to dynamically adjust the VM placement scheme over time. It should be noted that most of the existing studies, however, dealt with this problem either by ignoring its dynamic aspect or by proposing solutions that are not suitable for a geographically distributed cloud infrastructure. In this paper, exact as well as heuristic solutions based on Integer Linear programming (ILP) formulations are proposed. Our work focuses also on the problem of scheduling the VM migration by finding the best migration sequence of intercommunicating VMs that minimizes the resulting traffic on the backbone network. The proposed algorithms execute within a reasonable time frame to readjust VM placement scheme according to the perceived demand. Our aim is to use VM migration as a tool for dynamically adjusting the VM placement scheme while minimizing the network traffic generated by VM communication and migration. Finally, we demonstrate the effectiveness of our proposed algorithms by performing extensive experiments and simulation.
Polymer Coatings Reduce Electro-osmosis (1989)

Poly(ethylene glycol) film controls electrostatic potential. Electro-osmosis in quartz or glass chambers reduced or reversed by coating inside surface of chambers with monomacromolecular layers of poly(ethylene glycol). Stable over long times. Electrostatic potential across surface of untreated glass or plastic chamber used in electro-phoresis is negative and attracts cations in aqueous electrolyte. Cations solvated, entrains flow of electrolyte migrating toward cathode. Electro-osmotic flow interferes with desired electrophoresis of particles suspended in electrolyte. Polymer coats nontoxic, transparent, and neutral, advantageous for use in electrophoresis.
Latest developments in speckle contrast optical tomography (SCOT) for deep tissue blood flow imaging (2016)

Speckle contrast optical tomography allows for high-density measurement of deep tissue blood flow. With this technique we demonstrate three-dimensional reconstructions of blood flow in deep tissues using novel algorithms and detector arrays.
Adaptive liquid crystal lens with large focal length tunability (2006)

We demonstrate a tunable-focus lens using a spherical glass shell and a homogeneous liquid crystal (LC) cell. The inner surface of the glass shell and the bottom surface of the LC cell are coated with indium tin oxide (ITO) electrodes while the LC layer is sandwiched between the spherical and flat ITO electrodes. When a voltage is applied to the electrodes, a centro-symmetric gradient refractive index is generated within the LC layer and the focusing behavior occurs. Based on our analysis, the focal length tunability of the LC lens depends significantly on the filled material in the sag region. For the air-filled LC lens we designed, its focal length can be tuned from infinity to ~96 cm. A method for reducing the operating voltage is proposed.
Limitations on the use of short-pulse ultrasonic transducers for characterisation of small targets in solids (1981)

A convenient model explains the field pattern of a short-pulse broadband ultrasonic transducer in terms of a plane wave propagating in the geometrical region straight ahead of the face, together with a diffracted edge wave. That these waves actually exist is demonstrated by visualization and field-probing techniques. Interaction of plane and edge waves produces field patterns which, for the special case of continuous waves, lead to the definition of the nearfield and farfield regions. This paper extends the results of Weight and Hayman [J. Acoust. Soc. Am. 63, 396–404 (1978)] to solids. A simple model is proposed to take account of mode conversion of short pulses and hence to explain the added complexities of the echo system which arise from the use of these pulses to improve resolution. The consequences for materials evaluation are discussed.
Inspection of simulated weld penetration depth using laser-generated Lamb waves and wavelet signal processing (2015)

The Laser/EMAT ultrasonic (LEU) technique has raised interest in weld quality inspections because of its non-contact feature. However, the application of the technique in thin structures is challenging because of the difficulties in signal interpretations. In this work, a Continuous Wavelet Transform (CWT)-based algorithm is developed to calculate the transmission coefficients of laser generated Lamb waves. The transmission coefficients calculated using this method are shown to be able to predict the simulated weld penetration depths in thin structures.
Novel anti-Prelog stereospecific carbonyl reductases from Candida parapsilosis for asymmetric reduction of prochiral ketones (2011)

The application of biocatalysis to the synthesis of chiral molecules is one of the greenest technologies for the replacement of chemical routes due to its environmentally benign reaction conditions and unparalleled chemo-, regio- and stereoselectivities. We have been interested in searching for carbonyl reductase enzymes and assessing their substrate specificity and stereoselectivity. We now report a gene cluster identified in Candida parapsilosis that consists of four open reading frames including three putative stereospecific carbonyl reductases (scr1, scr2, and scr3) and an alcohol dehydrogenase (cpadh). These newly identified three stereospecific carbonyl reductases (SCRs) showed high catalytic activities for producing (S)-1-phenyl-1,2-ethanediol from 2-hydroxyacetophenone with NADPH as the coenzyme. Together with CPADH, all four enzymes from this cluster are carbonyl reductases with novel anti-Prelog stereoselectivity. SCR1 and SCR3 exhibited distinct specificities to acetophenone derivatives and chloro-substituted 2-hydroxyacetophenones, and especially very high activities towards ethyl 4-chloro-3-oxobutyrate, a β-ketoester with important pharmaceutical potential. Our study also showed that genomic mining is a powerful tool for the discovery of new enzymes.
Effects of Sodium Ions on DNA Duplex Oligomers:  Improved Predictions of Melting Temperatures (2004)

Melting temperatures, T(m), were systematically studied for a set of 92 DNA duplex oligomers in a variety of sodium ion concentrations ranging from 69 mM to 1.02 M. The relationship between T(m) and ln [Na(+)] was nonlinear over this range of sodium ion concentrations, and the observed melting temperatures were poorly predicted by existing algorithms. A new empirical relationship was derived from UV melting data that employs a quadratic function, which better models the melting temperatures of DNA duplex oligomers as sodium ion concentration is varied. Statistical analysis shows that this improved salt correction is significantly more accurate than previously suggested algorithms and predicts salt-corrected melting temperatures with an average error of only 1.6 degrees C when tested against an independent validation set of T(m) measurements obtained from the literature. Differential scanning calorimetry studies demonstrate that this T(m) salt correction is insensitive to DNA concentration. The T(m) salt correction function was found to be sequence-dependent and varied with the fraction of G.C base pairs, in agreement with previous studies of genomic and polymeric DNAs. The salt correction function is independent of oligomer length, suggesting that end-fraying and other end effects have little influence on the amount of sodium counterions released during duplex melting. The results are discussed in the context of counterion condensation theory.
Synthesis of New Hydrated Geranylphenols and in Vitro Antifungal Activity against Botrytis cinerea (2016)

Geranylated hydroquinones and other geranylated compounds isolated from Aplydium species have shown interesting biological activities. This fact has prompted a number of studies where geranylated phenol derivatives have been synthesized in order to assay their bioactivities. In this work, we report the synthesis of a series of new hydrated geranylphenols using two different synthetic approaches and their inhibitory effects on the mycelial growth of Botrytis cinerea. Five new hydrated geranylphenols were obtained by direct coupling reaction between geraniol and phenol in dioxane/water and using BF₃·Et₂O as the catalyst or by the reaction of a geranylated phenol with BF₃·Et₂O. Two new geranylated quinones were also obtained. The synthesis and structural elucidation of all new compounds is presented. All hydrated geranylphenols efficiently inhibit the mycelial growth of B. cinerea. Their activity is higher than that observed for non-hydrated compounds. These results indicate that structural modification on the geranyl chain brings about an enhancement of the inhibition effect of geranylated phenol derivatives.
Blue-green emissive cationic iridium(<scp>iii</scp>) complexes using partially saturated strongly-donating guanidyl-pyridine/-pyrazine ancillary ligands (2015)

A new class of cationic iridium(III) complexes of the form [(C(∧)N)2Ir(N(∧)N)][PF6] is reported, where C(∧)N = cyclometallating 2-phenylpyridinato, ppy, or 2-(2,4-difluorophenyl)-5'-methylpyridinato, dFMeppy, and N(∧)N = guanidyl-pyridine, gpy, or -pyrazine, gpz, as the ancillary ligand. A large blue-shift in the emission coupled with a 7-to-9 fold enhancement in photoluminescence quantum yield and microsecond emission lifetimes were observed for the complexes containing the partially saturated gpy ligand as compared to the benchmark complex [(ppy)2Ir(bpy)][PF6], C1, where bpy is 2,2'-bipyridine.
Designing advanced intermetallic titanium aluminide alloys for additive manufacturing (2021)

Lightweight intermetallic γ-TiAl based alloys are innovative high-temperature structural materials. So far, these alloys are in use as turbine blades or turbocharger turbine wheels in advanced aerospace and automotive engines, where they are produced by means of investment casting as well as wrought processing, e.g. hot-forging. Through the development of powder-based additive manufacturing processes within the last decade, a real paradigm shift for future component production as well as their design and materials properties was created. While so-called proven alloy systems are presently used worldwide for additive manufacturing, the approach of this work is the development of novel process-adapted γ-TiAl based alloys, which on the one hand fulfill the specific requirements of additive manufacturing and on the other hand provide excellent high temperature properties after a suitable heat treatment. Based on the concept of an engineering γ-TiAl based alloy, i.e. the so-called TNM alloy, two alloys are presented. Due to the chemical reactivity of titanium aluminide alloys, electron beam melting processes come into consideration as production methods using optimized manufacturing parameters, providing dense components with only small variations in the Al content between the individual powder layers, which is a decisive factor for the subsequent heat treatment above the γ solvus temperature. The additively produced samples show a fine equiaxed microstructure, whereas the heat-treated samples exhibit a fully lamellar α₂/γ microstructure with an excellent creep resistance. In summary, the adaptation of the additive manufacturing parameters in combination with innovative alloys and subsequent heat treatments are the basis for producing reliable high-performance TiAl components in the near future.
On multi-scale feature detection using filter banks (2002)

A discrete filtering framework is proposed for multiscale feature detection. The approach starts by choosing the sampling rate for the highest resolution filter of a given signal. Subsequently, a bank of filters for a multiscale representation of that signal is designed by least-square approximation. With this signal representation, multiscale maximum a-posteriori (MAP) detectors are designed for the detection of specific features, such as impulses and edges, without specific knowledge of the signal, the appropriate scale of detection and noise. The approach enables the detection of features with very little or no prior information.
PIEZOELECTRIC SINGLE CRYSTAL 6H SILICON CARBIDE MICROELECTROMECHANICAL RESONATORS (2018)

Piezoelectrically driven and sensed single-crystalline 6H silicon carbide (SiC) microelectromechanical resonators were designed and fabricated on a novel 100 mm silicon carbide on insulator (SiCOI) process. The prototype resonators have frequencies in the UHF range (464 MHz) with quality factors (Qs) as high as 7,400 for an f*Q product of 3.4x10 12 . Measurements at temperatures up to +200C and RF drive levels of up to 30 Vac demonstrate that these resonators are robust for high temperature and high power applications.
Low-Cost MEMS Packaging Using Polymer-Based Air-Gaps (2014)

The improvements in microelectromechanical systems (MEMS) have been traditionally focused more on the functionality and sensitivity of devices. However, packaging of MEMS devices has become a bottleneck mainly due to a wide range of device dimensions and packages being device-specific. In this study, we present a low-cost, sacrificial polymer-based MEMS packaging using air-gaps. Air-gaps were fabricated with poly(propylene carbonate) (PPC) as the sacrificial material and Cyclotene 4026 (BCB) as the overcoat. BCB was found to provide excellent mechanical support for the air cavity during the decomposition of the sacrificial material at high temperature and after decomposition at room temperature. Initial results were found to be promising in terms of before-and-after resonant spectra changes, i.e. <0.1% change in resonant frequency, and <5.2% change in quality factor. Two possible schemes of air-gap MEMS packaging are presented: (i) air-gap structures with BCB overcoat cap, and (ii) air-gap structures without BCB overcoat cap. Both schemes utilize epoxy overmolding as the protective layer.
Impact of Whey Protein Emulsifiers on the Oxidative Stability of Salmon Oil-in-Water Emulsions (2003)

To obtain a better understanding of how the interfacial region of emulsion droplets influences lipid oxidation, the oxidative stability of salmon oil-in-water emulsions stabilized by whey protein isolate (WPI), sweet whey (SW), beta-lactoglobulin (beta-Lg), or alpha-lactalbumin (alpha-La) was evaluated. Studies on the influence of pH on lipid oxidation in WPI-stabilized emulsions showed that formation of lipid hydroperoxides and headspace propanal was much lower at pH values below the protein's isoelectric point (pI), at which the emulsion droplets were positively charged, compared to that at pH values above the pI, at which the emulsion droplets were negatively charged. This effect was likely due to the ability of positively charged emulsion droplets to repel cationic iron. In a comparison of lipid oxidation rates of WPI-, SW-, beta-Lg-, and alpha-La-stabilized emulsions at pH 3, the oxidative stability was in the order of beta-Lg > or = SW > alpha-La > or = WPI. The result indicated that it was possible to engineer emulsions with greater oxidative stability by using proteins as emulsifier, thereby reducing or eliminating the need for exogenous food antioxidants.
Skipping Multiple Exons of Dystrophin Transcripts Using Cocktail Antisense Oligonucleotides (2013)

Duchenne muscular dystrophy (DMD) is one of the most common and lethal genetic disorders, with 20,000 children per year born with DMD globally. DMD is caused by mutations in the dystrophin (DMD) gene. Antisense-mediated exon skipping therapy is a promising therapeutic approach that uses short DNA-like molecules called antisense oligonucleotides (AOs) to skip over/splice out the mutated part of the gene to produce a shortened but functional dystrophin protein. One major challenge has been its limited applicability. Multiple exon skipping has recently emerged as a potential solution. Indeed, many DMD patients need exon skipping of multiple exons in order to restore the reading frame, depending on how many base pairs the mutated exon(s) and adjacent exons have. Theoretically, multiple exon skipping could be used to treat approximately 90%, 80%, and 98% of DMD patients with deletion, duplication, and nonsense mutations, respectively. In addition, multiple exon skipping could be used to select deletions that optimize the functionality of the truncated dystrophin protein. The proof of concept of systemic multiple exon skipping using a cocktail of AOs has been demonstrated in dystrophic dog and mouse models. Remaining challenges include the insufficient efficacy of systemic treatment, especially for therapies that target the heart, and limited long-term safety data. Here we review recent preclinical developments in AO-mediated multiple exon skipping and discuss the remaining challenges.
The observation of scintillation in a hydrated inorganic compound: CeCl3·6H2O (2013)

We have recently reported the discovery of a family of rare-earth metal-organic single-crystal scintillators based on Ce3+ as the activator ion. Starting with the CeCl3(CH3OH)4 prototype, this family of scintillators has recently been extended to include complex metal-organic adducts produced by reacting CeCl3 with heavier organics (e.g., isomers of propanol and butanol). Some of these rare-earth metal-organic materials incorporated waters of hydration in their structures, and the observation of scintillation in these hydrated compounds was an original finding for any solid scintillator. In the present work, we report the observation of gamma-ray-excited scintillation in an inorganic hydrated material, namely, single-crystal monoclinic CeCl3·6H2O. This observation shows that the mechanisms of the various scintillation energy-transfer processes are not seriously inhibited by the presence of waters of hydration in an inorganic material and that the observation of scintillation in other hydrated inorganic compounds is not precluded.
The role of enterovirus in chronic fatigue syndrome (2005)

Two and a half decades after coining of the term chronic fatigue syndrome (CFS), the diagnosis of this illness is still symptom based and the aetiology remains elusive. Enteroviruses are well known causes of acute respiratory and gastrointestinal infections, with tropism for the central nervous system, muscles, and heart. Initial reports of chronic enteroviral infections causing debilitating symptoms in patients with CFS were met with skeptism, and had been largely forgotten for the past decade. Observations from in vitro experiments and from animal models clearly established a state of chronic persistence through the formation of double stranded RNA, similar to findings reported in muscle biopsies of patients with CFS. Recent evidence not only confirmed the earlier studies, but also clarified the pathogenic role of viral RNA through antiviral treatment. This review summarises the available experimental and clinical evidence that supports the role of enterovirus in chronic fatigue syndrome.
Identification of<i>nodS</i>and<i>nodU,</i>Two Inducible Genes Inserted Between the<i>Bradyrhizobium japonicum nodYABC</i>and<i>nodIJ</i>Genes (1990)

The so-called common nodulation (nod) gene cluster of Bradyrhizobium japonicum is characterized by a unique composition of genes that are arranged in the following order: nodY, nodA, nodB, nodC, nodS, nodU, nodI, nodJ. As reported here, the identification of the two new genes nodS and nodU resulted from the DNA sequencing of a 4.5-kilobase nodC-downstream region covering nodS, nodU, nodI, and nodJ. The predicted NodS, NodU, NodI, and NodJ proteins had the following respective amino acid (aa) lengths and molecular weights (Mr): 209 aa, Mr 23,405; 569 aa, Mr 62,068; 306 aa, Mr 34,127; and 262 aa, Mr 28,194. The 3' end of nodC overlapped the 5' end of nodS by 71 nucleotides. Using translational fusions of lacZ to nodC, nodS, and nodU, the expression of these genes was shown to be inducible by the isoflavone daidzein and depended on transcription from a DNA region farther upstream. These data and the adjacent location of all genes suggested the existence of a nodYABCSUIJ operon. The nodI and nodJ gene products shared about 70% sequence similarity with the corresponding Rhizobium leguminosarum bv. viciae proteins; NodI belongs to the family of ATP-binding proteins that are constituents of bacterial binding protein-dependent transport systems. By interspecies hybridization, DNA regions homologous to nodSU were detected in other strains of Bradyrhizobium. Likewise, nodS- and nodU-like genes were identified in Rhizobium sp. strain NGR234 (A. Lewin, E. Cervantes, W. Chee-Hoong, and W. J. Broughton, Molecular Plant-Microbe Interactions 3:317-326, 1990) in which nodS confers host specificity for Leucaena leucocephala.(ABSTRACT TRUNCATED AT 250 WORDS)