gebhart/patrepeval huggingface dataset:
Rare Organometallic Complex of Divalent, Four-Coordinate Iridium:  Synthesis, Structural Characterization, and First Insights into Reactivity (2004)

An application of the new sterically bulky P∧O bidentate phosphine tBu2PC(CF3)2OH (1) in the cyclometalation of 2-(3,5-bis(trifluoromethyl)phenyl)-4-methylpyridine (4) by IrCl3 resulted in the stabilization of unusual coordination states of iridium: from the rare example of a mononuclear, paramagnetic, square-planar IrII complex, trans-Ir[η2-OC(CF3)2PtBu2]2 (2), to a coordinatively unsaturated, five-coordinated monohydride, trans-Ir(H)[η2-OC(CF3)2PtBu2]2 (3), and a mono-cyclometalated complex, C∧NIr(H)(CO)[η2-OC(CF3)2PtBu2] (6). The complex 2 can be synthesized by two alternative methods: by the aerial oxidation of 3 in the catalytic presence of a base, such as Et4NOH, or by the sublimation of 3 under vacuum. The IrII complex 2 undergoes hydrogenation to the IrIII−H complex 3. The reaction between carbon monoxide and a THF solution of complex 2 led to the reduction to the IrI complex trans-Ir(CO)[η2-OC(CF3)2PtBu2][η1-tBu2PC(CF3)2OH] (11). The C-cyclometalated complex Ir[η2-OC(CF3)2PtBu2][η3-CH2CMe2P(tBu)C(CF3)2O] (12) is formed upon heating of aprotic solutions of complex 2. The square-pyramidal five-coordinate IrIII hydride 3 reacts with sterically small ligands to form coordinately saturated octahedral species. For example, carbon monoxide forms trans-Ir(H)(CO)[η2-OC(CF3)2PtBu2]2 (9) and 4-pyrrolidin-1-yl-pyridine (L) gives trans-Ir(H)(L)[η2-OC(CF3)2PtBu2]2 (10). There is a significant difference in bond lengths between the oxygen and iridium atoms in the divalent state versus the trivalent state for equivalent ligands according to X-ray analysis. Divalent iridium has an average IrII−O distance of 1.970(2) Å, while trivalent iridium has an average IrIII−O distance of 1.996(2) Å. The reinvestigation of the original claim in the 1970s on the isolation of a square-planar IrII complex in the reaction between the phosphine tBu2PC6H3(OMe)2-2,6 (15) and IrCl3 in 2-propanol resulted in the isolation of two square-pyramidal, five-coordinate IrIII hydrides: trans-Ir(H)[η2-OC6H3(iPr-6)(OMe-3)PtBu2]2 (16) and trans-Ir(H)[η2-OC6H2(OMe-3)PtBu2]2 (17). The X-ray analysis of 17 reveals that the triclinic unit cell parameters are in agreement with the published room-temperature unit cell for the IrII complex. Bond lengths between the iridium and oxygen atoms in 17 and in the published IrII complex are 2.012(3) and 2.00 Å, respectively. This falls into our range for red IrIII complexes. The 1H NMR spectrum of 17 shows a characteristic upfield triplet for IrIII−H at δ −48.0 (t, 2JP,H = 11.9 Hz). The aerial oxidation of 16 in the catalytic presence of base led to the paramagnetic IrIV complex Ir[η3-OCH2CMe2P(tBu)C6H3(iPr-6)(OMe-3)-O]2 (20).
Thermal Modeling of Vapor Chamber Heat Spreaders and Model Validation (2020)

High density microprocessor packages are being deployed to achieve system performance improvements. However, the non-uniform heat dissipation characteristics of such packages has led to renewed interest in vapor chambers and heat pipes for heat spreading and transport. In this paper an approach to model the thermo-hydrodynamic performance of vapor chambers for cooling of microprocessor packages is presented. Model validation against data available in literature showed a very good agreement. The validated model was then used to study the performance sensitivity to vapor chamber design and operational parameters such as wick thickness, wick type, evaporator side heat input and condenser side heat extraction.
Modeling and simulation of heat pump air conditioning unit intending energy capacity reduction of energy storage system in microgrid (2011)

To compensate power fluctuation caused by renewable energy sources, the concept of load control has been proposed. This concept is an idea to control the power consumption of loads in the power grid in order to contribute to the grid operator. In this paper, control of a heat pump air-conditioner is focused. Based on heat pump's characteristic obtained from experiments, a simple heat pump model is proposed. A simulation to compensate power fluctuation in a microgrid by use of the heat pump is conducted and the effect of the heat pump control is analyzed. The results of the simulation show that the necessary capacity of energy storage system(ESS) can be reduced by controlling the power consumption of the heat pump. At the same time, temperature simulation of the room which is air-conditioned by the heat pump is conducted to analyze the effect of load control to the user of the heat pump. The results show that the temperature fluctuation caused by load control is small enough to ensure the thermal comfort of the room. The feature of this paper is that the effect of the load control using a heat pump air-conditioner is discussed with consideration to the user's convenience.
Theoretical BER Evaluation of Passive RFID Tag-To-Tag Communications (2020)

The concept of UHF RFID passive tag-to-tag communication has been introduced and opens new promising perspectives in the field of Internet-of-Things. This concept enables two powerless tags to exchange information using an external source. Moreover, a simulation framework has been proposed as a tool allowing the performance evaluation of tag-to-tag radio links in terms of Bit Error Rate (BER). The aim of this paper is to provide a theoretical framework for BER estimation. The theoretical framework takes into account various parameters such as modulation rate, receivers topology and the electromagnetic coupling of the tags. Furthermore, in order to validate the obtained results, they are compared with the ones obtained by realistic simulations.
Fluorine influence in the mass spectrometric patterns in β‐hydroxy alkyl aryl sulphoxides. Part 5 (1990)

Abstract The electron ionization mass spectrometry of some β‐hydroxy alkyl aryl sulphoxides halogenated in the γ‐position is described and the mechanism of the common fragmentation patterns are discussed with the aid of linked scans at constant B/E, mass‐analysed ion kinetic energy spectra and labelling experiments. The influence of the presence of halogens is also discussed.
Collagen type I is not under autocrine control by transforming growth factor-beta 1 in normal and scleroderma fibroblasts. (1994)

Our data give no support to the hypothesis that TGF-beta can maintain the SSc phenotype in vitro or that it is able to induce this phenotype. The inducibility of TGF-beta receptor mRNA in SSc fibroblasts after exposure to TGF-beta suggests that the lack of sustained elevation in collagen synthesis is not due to lack of responsiveness by the fibroblasts but is rather a reflection of the transient nature of TGF-beta-induced fibrosis.
Complex Permittivity Detection of Organic Chemicals and Mixtures Using a 0.5–3-GHz Miniaturized Spectroscopy System (2013)

In this paper, a miniaturized broadband dielectric spectroscopy system is presented for complex permittivity detection of organic chemicals in the 0.5-3-GHz frequency range. A sensing capacitor exposed to a material under test exhibits changes in its capacitance and resistance according to the complex permittivity. The sensing capacitor is embedded inside a wideband impedance divider circuit excited by an external microwave signal at the sensing frequency. The amplitude and phase variation of the microwave signal across the impedance divider is a function of the complex permittivity. Wideband in-phase and quadrautre mixers are used to measure the resulting amplitude and phase variations. A unique calibration algorithm using reference liquids is applied to the fabricated sensor and sensor characteristics are extracted using 2-D surface fitting. Complex permittivity detection of pure organic chemicals is performed with an error less than 1.5% in the 0.5-3-GHz frequency range. The measured points of the permittivity versus frequency are used to estimate the static permittivity using extrapolation with an error less than 1.5% compared to theoretical values. The sensor is also applied to measure the permittivities of binary mixtures with a mixing ratio accuracy of 1%.
New Phosphorylating Agents for the Synthesis of Phosphatidylethanolamines (2021)

Abstract The preparation of three novel phosphorylating agents and their application toward the synthesis of phosphatidylethanolamines is described. These reagents are stable to air and moisture, and phosphorylate glycerols in good yield. The experimental procedures using these phosphorylating agents are simple. Moreover, the appropriate reagent can be selected based on the desired functional groups of the targeted phosphatidylethanolamine.
Dynamic Federations for 6G Cell-Free Networking: Concepts and Terminology (2022)

Cell-Free networking is one of the prime candidates for 6G networks. Despite being capable of providing the 6G needs, practical limitations and considerations are often neglected in current research. In this work, we introduce the concept of federations to dynamically scale and select the best set of resources, e.g., antennas, computing and data resources, to serve a given application. Next to communication, 6G systems are expected to provide also wireless powering, positioning and sensing, further increasing the complexity of such systems. Therefore, each federation is self-managing and is distributed over the area in a cell-free manner. Next to the dynamic federations, new accompanying terminology is proposed to design cell-free systems taking into account practical limitations such as time synchronization and distributed processing. We conclude with an illustration with four federations, serving distinct applications, and introduce two new testbeds to study these architectures and concepts.
Chirality amplification and detection by tactoids of lyotropic chromonic liquid crystals (2015)

Detection of chiral molecules requires amplification of chirality to measurable levels. Typically, amplification mechanisms are considered at the microscopic scales of individual molecules and their aggregates. Here we demonstrate chirality amplification and visualization of structural handedness in water solutions of organic molecules that extends over the scale of many micrometers. The mechanism is rooted in the long-range elastic nature of orientational order in lyotropic chromonic liquid crystals (LCLCs) formed in water solutions of achiral disc-like molecules. The nematic LCLC coexists with its isotropic counterpart, forming elongated tactoids; the spatial confinement causes a structural twist even when the material is nonchiral. Minute quantities of chiral molecules such as the amino acid l-alanine and limonene transform the racemic array of left- and right-twisted tactoids into a homochiral set. The left and right chiral enantiomers are readily distinguished from each other as the induced structural handedness is visualized through a simple polarizing microscope observation. The effect is important for developing our understanding of chirality amplification mechanisms; it also might open up new possibilities in biosensing.
Supermolecular self organization via molecular aggregation. Non-discotic three chain diols displaying a hexagonal columnar phase (1990)

Abstract A new class of mesogen formed by three chain diols is described. These compounds consist of a central part to which three aliphatic chains of various length (n = 4–14) are attached at one end and two hydroxy groups at the other. X-ray scattering, dilatometric measurements, dielectric and Kerr relaxation studies were carried out. Both X-ray investigations, dielectric and electro-optic studies revealed that the molecules are aggregated in the isotropic fluid state and that hydrogen bonding and dipole correlation contribute to this aggregation. Columnar assemblies of up to several hundred molecules are orientationally correlated in the isotropic fluid phase. Correlated reorientations occur in the presence of external electric fields. The X-ray data show that the aggregates pack in a hexagonal way at lower temperatures giving a structure which strongly resembles that of the hexagonal disordered columnar phase. This anisotropic phase can be quenched to a glassy liquid-crystalline state. It is evident that the mesogenic properties of this new class of compounds are a function of the disc-like shape of the aggregates rather than the shapes of the individual molecules.
ChemInform Abstract: Synthesis of 2,6‐Di‐tert‐Butylphenols Linked to 1,3,4‐Oxadiazoles and 1,3,4‐Thiadiazoles. (1995)

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.
Benchmarking to the Gold Standard: Hyaluronan‐Oxime Hydrogels Recapitulate Xenograft Models with In Vitro Breast Cancer Spheroid Culture (2019)

Many 3D in vitro models induce breast cancer spheroid formation; however, this alone does not recapitulate the complex in vivo phenotype. To effectively screen therapeutics, it is urgently needed to validate in vitro cancer spheroid models against the gold standard of xenografts. A new oxime-crosslinked hyaluronan (HA) hydrogel is designed, manipulating gelation rate and mechanical properties to grow breast cancer spheroids in 3D. This HA-oxime breast cancer model maintains the gene expression profile most similar to that of tumor xenografts based on a pan-cancer gene expression profile (comprising 730 genes) of three different human breast cancer subtypes compared to Matrigel or conventional 2D culture. Differences in gene expression between breast cancer cultures in HA-oxime versus Matrigel or 2D are confirmed for 12 canonical pathways by gene set variation analysis. Importantly, drug response is dependent on the culture method. Breast cancer cells respond better to the Rac inhibitor (EHT-1864) and the PI3K inhibitor (AZD6482) when cultured in HA-oxime versus Matrigel. This study demonstrates the superiority of an HA-based hydrogel as a platform for in vitro breast cancer culture of both primary, patient-derived cells and cell lines, and provides a hydrogel culture model that closely matches that in vivo.
Developments in CO2 research (2021)

CO2 can be a good solvent for many compounds when used in its compressed liq- uid or supercritical fluid state. Above its critical temperature and critical pressure (Tc = 31 °C, Pc = 73.8 bar), CO2 has liquid-like densities and gas-like viscosities, which allows for safe commercial and laboratory operating conditions. Many small molecules are readily soluble in CO2, whereas most macromolecules are not. This has prompted development of several classes of small molecule and polymeric surfactants that enable emulsion and dispersion polymerizations as well as other technological processes.
Audio-Visual Speech Codecs: Rethinking Audio-Visual Speech Enhancement by Re-Synthesis (2022)

Since facial actions such as lip movements contain significant information about speech content, it is not surprising that audio-visual speech enhancement methods are more accurate than their audio-only counterparts. Yet, state-of-the-art approaches still struggle to generate clean, realistic speech without noise artifacts and unnatural distortions in challenging acoustic environments. In this paper, we propose a novel audio-visual speech enhancement framework for high-fidelity telecommunications in AR/VR. Our approach leverages audio-visual speech cues to generate the codes of a neural speech codec, enabling efficient synthesis of clean, realistic speech from noisy signals. Given the importance of speaker-specific cues in speech, we focus on developing personalized models that work well for individual speakers. We demonstrate the efficacy of our approach on a new audio-visual speech dataset collected in an unconstrained, large vocabulary setting, as well as existing audio-visual datasets, outperforming speech enhancement baselines on both quantitative metrics and human evaluation studies. Please see the supplemental video for qualitative results at https://github.com/facebookresearch/facestar/releases/download/paper_materials/video.mp4.
Electrochemical deposition of Pt nanoparticles on carbon nanotube patterns for glucose detection (2010)

Single-walled carbon nanotube (SWCNT) microarrays are successfully patterned on SiO(2) substrates based on an evaporation-induced self-assembly mechanism. On these SWCNT micropatterns, the highly electroactive polycrystalline Pt nanoparticles (PtNPs) are deposited by using the electrochemical method. The obtained PtNP-SWCNT nanocomposites exhibit a low detection limit for hydrogen peroxide (4 microM). The further investigation on a glucose oxidase (GOx)/BSA/PtNP-SWCNT based biosensor indicates that the detection limit and sensitivity for glucose are 0.04 mM and 4.54 microA mM(-1) cm(-2), respectively. Our results prove that the improved electrocatalytic activity originates from the PtNP-SWCNT micropatterns, which provide a potential platform to immobilize different enzymes used for bioelectrochemical applications.
Preserving surface area and porosity during fabrication of silicon aerocrystal particles from anodized wafers (2020)

Abstract Porous silicon layers on wafers are commonly converted into particles by mechanical milling or ultrasonic fragmentation. The former technique can rapidly generate large batches of microparticles. The latter technique is commonly used for making nanoparticles but processing times are very long and yields, where reported, are often very low. With both processing techniques, the porosity and surface area of the particles generated are often assumed to be similar to those of the parent film. We demonstrate that this is rarely the case, using air-dried high porosity and supercritically dried aerocrystals as examples. We show that whereas ball milling can more quickly generate much higher yields of particles, it is much more damaging to the nanostructures than ultrasonic fragmentation. The latter technique is particularly promising for silicon aerocrystals since processing times are reduced whilst yields are simultaneously raised with ultrahigh porosity structures. Not only that, but very high surface areas (&gt; 500 m 2 /g) can be completely preserved with ultrasonic fragmentation.
Agrobacterium tumefaciens-mediated Transformation of Delphinium spp. (2002)

A successful transformation method was reported on Delphinium spp., using Agrobacterium tumefaciens. Elongated hypocotyl and cotyledon petiole segments were infected with Agrobacterium tumefaciens strain LBA4404, which harbored a binary vector plasmid, pIG121-Hm, which included the β-glucuronidase (GUS) gene (with an intron) as a reporter gene, and the neomycin phosphotransferase II gene and the hygromycin phosphotransferase gene as selection markers. Explants were cultured on Murashige and Skoog medium supplemented with 1.0mgl-1 thidiazuron, 1.0mgl-1 2, 4-dichlorophenoxyacetic acid, 300mgl-1 ticarcillin, and 5mgl-1 hygromycin or 100mgl-1 kanamycin (selection medium) for regeneration. Transformation was confirmed by histochemical assays of GUS activity in plant tissues, and by PCR analysis of the GUS gene. Through four experiments, six independent GUS-positive regenerants were obtained out of 1276 explants.
Solid-Liquid Transitions of Horizontally Shaken Dry Granular Materials (2020)

Extensive experiments, simulations, and models address the transition between ‘fluid’ and ‘solid’ states of granular material. Using horizontal shaking a material layer undergoes a backward bifurcation between a solid-like state stationary in the frame of the shaker and a fluid-like state moving/sloshing on top of a solid layer. Both the solid/fluid transition and the reverse fluid/solid transition have similar divergent time scales τ = τ*|ϵ|− β , where e is a small change past either critical point. For both transitions β = 1 and τ* = 0.5 sec. Before transition there is a ‘gas’ of free particles sliding on the bulk material surface. Although these particles are few in number, suppressing them with a thin plastic strip removes the hysteresis: the fluidization transition becomes forward. A Coulomb friction model predicts a forward rather than a hysteretic transition. A model with friction changing continuously between static and dynamic values produces the hysteresis seen in experiments.
Optical Bistability with Two Serially Integrated InP-SOAs on a Single Chip (2015)

Optical bistability has been achieved with two serially integrated MQW-InP SOAs in reverse-bias on a single chip. We demonstrate that switching speed in GHz range is possible and discuss performance limitations of the bistable device.
Recent advances in the IBM GALE Mandarin transcription system (2008)

This paper describes the system and algorithmic developments in the automatic transcription of Mandarin broadcast speech made at IBM in the second year of the DARPA GALE program. Technical advances over our previous system include improved acoustic models using embedded tone modeling, and a new topic-adaptive language model (LM) rescoring technique based on dynamically generated LMs. We present results on three community-defined test sets designed to cover both the broadcast news and the broadcast conversation domain. It is shown that our new baseline system attains a 15.4% relative reduction in character error rate compared with our previous GALE evaluation system. And a further 13.6% improvement over the baseline is achieved with the two described techniques.
ChemInform Abstract: Pd‐Catalyzed Regiospecific Reductive Ring Opening of Epoxides and Glycidic Esters. (1995)

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.
Three-Dimensional Hybrid Integration Technology of CMOS, MEMS, and Photonics Circuits for Optoelectronic Heterogeneous Integrated Systems (2011)

We have developed a new 3-D hybrid integration technology of complementary metal-oxide-semiconductors, microelectromechanical systems (MEMS), and photonics circuits for optoelectronic heterogeneous integrated systems. We have overcome the fabrication difficulties of optoelectromechanical and microfluidics hybrid integration. In order to verify the applied 3-D hybrid integration technology, we fabricated a 3-D optoelectronic multichip module composed of large-scale integration (LSI), MEMS, and photonics devices. The electrical chips of amplitude-shift keying (ASK) LSI, passive, and pressure-sensing MEMS were mounted onto an electrical Si interposer with through-silicon vias (TSVs) and microfluidic channels. Photonics chips of vertical-cavity surface-emitting lasers and photodiodes were embedded into an optical Si interposer with TSVs. The electrical and optical interposers were precisely bonded together to form a 3-D optoelectronic multichip module. The photonics and electrical devices could communicate via TSVs. The photonics devices could be connected via an optical waveguide formed onto the optical interposer. Microfluidic channels were formed into the interposer by a wafer-direct bonding technique for heat sinking from high-power LSIs. In this paper, we evaluated the basic functions of individual chips of LSI, MEMS, and photonics devices as they were integrated into the 3-D optoelectronic multichip module to verify the applied 3-D hybrid integration technology. LSI, passive, MEMS, and photonics devices were successfully implemented. The 3-D hybrid integration technology is capable of providing a powerful solution for realizing optoelectronic heterogeneous integrated systems.