High-performance heat resistant insulation materials for coils

A new impregnating epoxide resin has been developed by optimizing cross-linking densities. The resin satisfies the thermal index of 210C: this is the first time an epoxide system without a heterocyclic ring has done so. Thermal class 220C insulating systems of traction motor coils are developed by interaction of the impregnating epoxide resin and epoxide binding resin in a new insulating tape. The newly developed epoxide impregnating resin has low viscosity and very good workability. Therefore, electrically insulated coils of various classes of heat resistance, such as class C (> 180C), class H (180 C) and class F (155C), can be prepared by using only a single kind of impregnating resin, by selecting the insulating tape and hardening conditions. It is unnecessary to keep various kinds of impregnating resin corresponding to the different beat resistant grades and it is possible to decrease drastically the amount of waste generated by using several different impregnating resins.

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Superionic Lithium Intercalation through 2 nm x 2 nm Columns in the Crystallographic Shear Phase Nb18W8O69

10.26434/chemrxiv.11231153.v1 ◽

2019 ◽

Author(s):

Kent Griffith ◽

Clare Grey

Keyword(s):

High Performance ◽

Rate Capability ◽

Block Size ◽

Lithium Intercalation ◽

Resonance Spectroscopy ◽

Complex Metal Oxides ◽

Battery Electrode ◽

Crystallographic Shear ◽

Battery Material ◽

First Time

Nb18W8O69 (9Nb2O5×8WO3) is the tungsten-rich end-member of the Wadsley–Roth crystallographic shear (cs) structures within the Nb2O5–WO3 series. It has the largest block size of any known, stable Wadsley–Roth phase, comprising 5 ´ 5 units of corner-shared MO6 octahedra between the shear planes, giving rise to 2 nm ´ 2 nm blocks. Rapid lithium intercalation is observed in this new candidate battery material and 7Li pulsed field gradient nuclear magnetic resonance spectroscopy – measured in a battery electrode for the first time at room temperature – reveals superionic lithium conductivity. In addition to its promising rate capability, Nb18W8O69 adds a piece to the larger picture of our understanding of high-performance Wadsley–Roth complex metal oxides.

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Development of an HPLC-UV Method for Quantification of Stattic

Current Pharmaceutical Analysis ◽

10.2174/1573412914666180523092957 ◽

2019 ◽

Vol 15 (6) ◽

pp. 568-573

Author(s):

Soheil Sedaghat ◽

Ommoleila Molavi ◽

Akram Faridi ◽

Ali Shayanfar ◽

Mohammad Reza Rashidi

Keyword(s):

High Performance ◽

Accurate Method ◽

Plasma Samples ◽

Promising Target ◽

Relative Standard ◽

Dimerization Inhibitor ◽

Oncogenic Protein ◽

First Time ◽

Transcription 3

Background: Signal transducer and activator of transcription 3 (STAT3), an oncogenic protein found constitutively active in many types of human malignancies, is considered to be a promising target for cancer therapy. Objective: In this study for the first time, a simple and accurate method has been developed for the determination of a STAT3 dimerization inhibitor called stattic in aqueous and plasma samples. Methods: A reverse-phase high-performance liquid chromatography (RP-HPLC) composed of C18 column as stationary phase, and the mixture of acetonitrile (60%) and water (40%) as mobile phase with a UV detection at 215 nm were applied for quantification of stattic. The developed method was validated by Food and Drug Administration (FDA) guideline. Results: The method provided a linear range between 1-40 and 2.5-40 µg mL-1 for aqueous and plasma samples, respectively, with a correlation coefficient of 0.999. The accuracy (as recovery) of the developed method was found to be between 95-105% for aqueous medium and 85-115% for plasma samples. The precision (as relative standard deviation) for aqueous and plasma samples was less than 6% and 15%, respectively. The sensitivity of the developed method based on FDA guideline was 1 µg mL-1 for aqueous and 2.5 µg mL-1 for plasma samples. Conclusion: These results show that the established method is a fast and accurate quantification for stattic in aqueous and plasma samples.

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The Effect of Surfactant-Modified Montmorillonite on the Cross-Linking Efficiency of Polysiloxanes

Materials ◽

10.3390/ma14102623 ◽

2021 ◽

Vol 14 (10) ◽

pp. 2623

Author(s):

Monika Wójcik-Bania ◽

Jakub Matusik

Keyword(s):

Total Pore Volume ◽

Cross Linking ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

The Cross ◽

Chain Lengths ◽

First Time ◽

Substituent Influence ◽

Benzyl Substituent

Polymer–clay mineral composites are an important class of materials with various applications in the industry. Despite interesting properties of polysiloxanes, such matrices were rarely used in combination with clay minerals. Thus, for the first time, a systematic study was designed to investigate the cross-linking efficiency of polysiloxane networks in the presence of 2 wt % of organo-montmorillonite. Montmorillonite (Mt) was intercalated with six quaternary ammonium salts of the cation structure [(CH3)2R’NR]+, where R = C12, C14, C16, and R’ = methyl or benzyl substituent. The intercalation efficiency was examined by X-ray diffraction, CHN elemental analysis, and Fourier transform infrared (FTIR) spectroscopy. Textural studies have shown that the application of freezing in liquid nitrogen and freeze-drying after the intercalation increases the specific surface area and the total pore volume of organo-Mt. The polymer matrix was a poly(methylhydrosiloxane) cross-linked with two linear vinylsiloxanes of different siloxane chain lengths between end functional groups. X-ray diffraction and transmission electron microscopy studies have shown that the increase in d-spacing of organo-Mt and the benzyl substituent influence the degree of nanofillers’ exfoliation in the nanocomposites. The increase in the degree of organo-Mt exfoliation reduces the efficiency of hydrosilylation reaction monitored by FTIR. This was due to physical hindrance induced by exfoliated Mt particles.

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Histochemical and Phytochemical Analysis of Lamium album subsp. album L. Corolla: Essential Oil, Triterpenes, and Iridoids

Molecules ◽

10.3390/molecules26144166 ◽

2021 ◽

Vol 26 (14) ◽

pp. 4166

Author(s):

Agata Konarska ◽

Elżbieta Weryszko-Chmielewska ◽

Anna Matysik-Woźniak ◽

Aneta Sulborska ◽

Beata Polak ◽

...

Keyword(s):

Essential Oil ◽

High Performance ◽

Glandular Trichomes ◽

Gas Chromatography Mass Spectrometry ◽

Phytochemical Analysis ◽

Lipophilic Compounds ◽

Histochemical Tests ◽

Microscopy Techniques ◽

Trichome Types ◽

First Time

The aim of this study was to conduct a histochemical analysis to localize lipids, terpenes, essential oil, and iridoids in the trichomes of the L. album subsp. album corolla. Morphometric examinations of individual trichome types were performed. Light and scanning electron microscopy techniques were used to show the micromorphology and localization of lipophilic compounds and iridoids in secretory trichomes with the use of histochemical tests. Additionally, the content of essential oil and its components were determined using gas chromatography-mass spectrometry (GC-MS). Qualitative analyses of triterpenes carried out using high-performance thin-layer chromatography (HPTLC) coupled with densitometric detection, and the iridoid content expressed as aucubin was examined with spectrophotometric techniques. We showed the presence of iridoids and different lipophilic compounds in papillae and glandular and non-glandular trichomes. On average, the flowers of L. album subsp. album yielded 0.04 mL/kg of essential oil, which was dominated by aldehydes, sesquiterpenes, and alkanes. The extract of the L. album subsp. album corolla contained 1.5 × 10−3 ± 4.3 × 10−4 mg/mL of iridoid aucubin and three triterpenes: oleanolic acid, β-amyrin, and β-amyrin acetate. Aucubin and β-amyrin acetate were detected for the first time. We suggest the use of L. album subsp. album flowers as supplements in human nutrition.

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Parametric instability in a free-evolving warped protoplanetary disc

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa3504 ◽

2020 ◽

Vol 500 (3) ◽

pp. 4248-4256

Author(s):

Hongping Deng ◽

Gordon I Ogilvie ◽

Lucio Mayer

Keyword(s):

Wave Equations ◽

Hydrodynamic Instability ◽

Parametric Instability ◽

Low Viscosity ◽

Crossing Time ◽

Particle Hydrodynamics ◽

Smoothed Particle ◽

First Time ◽

Bending Wave ◽

Grid Based

ABSTRACT Warped accretion discs of low viscosity are prone to hydrodynamic instability due to parametric resonance of inertial waves as confirmed by local simulations. Global simulations of warped discs, using either smoothed particle hydrodynamics or grid-based codes, are ubiquitous but no such instability has been seen. Here, we utilize a hybrid Godunov-type Lagrangian method to study parametric instability in global simulations of warped Keplerian discs at unprecedentedly high resolution (up to 120 million particles). In the global simulations, the propagation of the warp is well described by the linear bending-wave equations before the instability sets in. The ensuing turbulence, captured for the first time in a global simulation, damps relative orbital inclinations and leads to a decrease in the angular momentum deficit. As a result, the warp undergoes significant damping within one bending-wave crossing time. Observed protoplanetary disc warps are likely maintained by companions or aftermath of disc breaking.

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Nanostructured intermetallic InSb as a high-capacity and high-performance negative electrode for sodium-ion batteries

Sustainable Energy & Fuels ◽

10.1039/d1se00386k ◽

2021 ◽

Author(s):

Irshad Mohammad ◽

Lucie Blondeau ◽

Eddy Foy ◽

Jocelyne Leroy ◽

Eric Leroy ◽

...

Keyword(s):

Intermetallic Compound ◽

High Performance ◽

High Capacity ◽

Negative Electrode ◽

Sodium Ion ◽

Sodium Ion Batteries ◽

Negative Electrodes ◽

First Time

Following the trends of alloys as negative electrodes for Na-ion batteries, the sodiation of the InSb intermetallic compound was investigated for the first time. The benefit of coupling Sb with...

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Comparison of α-Tocopherol, α-Tocopherol Acetate, and α-Tocopheryl Polyethylene Glycol Succinate 1000 Absorption by Caco-2 TC7 Intestinal Cells

Nutrients ◽

10.3390/nu13010129 ◽

2020 ◽

Vol 13 (1) ◽

pp. 129

Author(s):

Charlotte Cuerq ◽

Claire Bordat ◽

Charlotte Halimi ◽

Emilie Blond ◽

Marion Nowicki ◽

...

Keyword(s):

Polyethylene Glycol ◽

High Performance ◽

Lipid Extraction ◽

Free Form ◽

Glycol Succinate ◽

Tocopherol Acetate ◽

Apical Side ◽

Basolateral Side ◽

Human Enterocyte ◽

First Time

(1) Background: vitamin E is often supplemented in the form of tocopherol acetate, but it has poor bioavailability and can fail to correct blood tocopherol concentrations in some patients with severe cholestasis. In this context, α-tocopheryl polyethylene glycol succinate 1000 (TPGS) has been of value, but very little is known about the mechanisms of its absorption. The aim of our work was to evaluate the mechanisms of absorption/secretion of TPGS compared to tocopherol acetate (TAC) and α-tocopherol by human enterocyte-like Caco-2 TC7 cells. (2) Methods: two weeks post-confluence Caco-2 cells were incubated with tocopherol- or TAC- or TPGS-rich mixed micelles up to 24 h and, following lipid extraction, TAC and tocopherol amounts were measured by high performance liquid chromatography (HPLC) in apical, cellular, and basolateral compartments. (3) Results: at equivalent concentrations of tocopherol in the apical side, the amounts of tocopherol secreted at the basolateral pole of Caco-2 cells are (i) significantly greater when the tocopherol is in the free form in the micelles; (ii) intermediate when it is in the TAC form in the micelles (p < 0.001); and (iii) significantly lower with the TPGS form (p < 0.0001). Interestingly, our results show, for the first time, that Caco-2 cells secrete one or more esterified forms of the vitamin contained in TPGS at the basolateral side.

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Hyperbranched polyamide modified graphene oxide-reinforced polyurethane nanocomposites with enhanced mechanical properties

RSC Advances ◽

10.1039/d1ra00654a ◽

2021 ◽

Vol 11 (24) ◽

pp. 14484-14494

Author(s):

Yahao Liu ◽

Jian Zheng ◽

Xiao Zhang ◽

Yongqiang Du ◽

Guibo Yu ◽

...

Keyword(s):

Mechanical Properties ◽

Graphene Oxide ◽

High Performance ◽

Cross Linking ◽

Elongation At Break ◽

Modified Graphene Oxide ◽

High Performance Composite ◽

Modified Graphene ◽

Polyurethane Nanocomposites ◽

Hyperbranched Polyamide

We successfully modified graphene oxide with amino-terminated hyperbranched polyamide (HGO), and obtained a high-performance composite with enhanced strength and elongation at break via cross-linking hydroxyl-terminated polybutadiene chains with HGO.

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An expanded isoindigo unit as a new building block for a conjugated polymer leading to high-performance solar cells

Journal of Materials Chemistry A ◽

10.1039/c3ta15291j ◽

2014 ◽

Vol 2 (15) ◽

pp. 5427-5433 ◽

Cited By ~ 34

Author(s):

Shugang Li ◽

Zhongcheng Yuan ◽

Jianyu Yuan ◽

Ping Deng ◽

Qing Zhang ◽

...

Keyword(s):

Solar Cells ◽

Solar Cell ◽

Building Block ◽

Conjugated Polymer ◽

High Performance ◽

Fill Factor ◽

Solar Cell Device ◽

Donor Acceptor ◽

First Time

An expanded isoindigo unit (IBTI) has been incorporated into a donor–acceptor conjugated polymer for the first time. The PCE of the solar cell device based on the new polymer reached 6.41% with a fill factor of 0.71.

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