STRENGTHENING OF PIPE TOOLS FOR COLD ROLLER ROLLING OF CORROSION-RESISTANT PIPES BY APPLICATION OF AMORPHOUS ALLOYS

In the production of pipes from corrosion-resistant steels on pipe rolling plants, the current problem is the low stability of the pipe tool. Therefore, the creation of high-performance and durable tools is associated primarily with the production and processing of materials that could withstand harsh working conditions. The technology of heat hardening of the pipe tool for cold roller rolling of corrosion-resistant pipes (rollers and support laths of HPTR mills) from 4Х5МФ1С steel which excludes the third holiday and uses drawing of a covering from powders of amorphous alloys 100…150 µm thick is offered in the work. As a result of the offered technology durability, wear resistance, and also hardness to HV0.1 950–1050 (in comparison with HV 587–690 on existing technology of heat treatment in factory conditions) increases. A wide range of studies of the structure of the coating and industrial tests of rollers and support bars. It is shown that gas-plasma coating of amorphous alloy based on Fe–Si–B system increases the hardness of the tool surface by 1.3–1.6 times and their stability by ~ 30…50%.

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Validated Stability Indicating HPTLC Method for the Estimation of Amoxapine in Different Stress Conditions

Current Pharmaceutical Analysis ◽

10.2174/1573412914666171228163122 ◽

2019 ◽

Vol 15 (3) ◽

pp. 273-279

Author(s):

Shweta G. Rangari ◽

Nishikant A. Raut ◽

Pradip W. Dhore

Keyword(s):

High Performance ◽

Limit Of Detection ◽

Degradation Products ◽

Analysis Data ◽

Peak Height ◽

Good Resolution ◽

Stability Indicating ◽

Limit Of Quantitation ◽

Wide Range ◽

Hptlc Method

Background:The unstable and/or toxic degradation products may form due to degradation of drug which results into loss of therapeutic activity and lead to life threatening condition. Hence, it is important to establish the stability characteristics of drug in various conditions such as in temperature, light, oxidising agent and susceptibility across a wide range of pH values.Introduction:The aim of the proposed study was to develop simple, sensitive and economic stability indicating high performance thin layer chromatography (HPTLC) method for the quantification of Amoxapine in the presence of degradation products.Methods:Amoxapine and its degraded products were separated on precoated silica gel 60F254 TLC plates by using mobile phase comprising of methanol: toluene: ammonium acetate (6:3:1, v/v/v). The densitometric evaluation was carried out at 320 nm in reflectance/absorbance mode. The degradation products obtained as per ICH guidelines under acidic, basic and oxidative conditions have different Rf values 0.12, 0.26 and 0.6 indicating good resolution from each other and pure drug with Rf: 0.47. Amoxapine was found to be stable under neutral, thermal and photo conditions.Results:The method was validated as per ICH Q2 (R1) guidelines in terms of accuracy, precision, ruggedness, robustness and linearity. A good linear relationship between concentration and response (peak area and peak height) over the range of 80 ng/spot to 720 ng/spot was observed from regression analysis data showing correlation coefficient 0.991 and 0.994 for area and height, respectively. The limit of detection (LOD) and limit of quantitation (LOQ) for area were found to be 1.176 ng/mL and 3.565 ng/mL, whereas for height, 50.063 ng/mL and 151.707 ng/mL respectively.Conclusion:The statistical analysis confirmed the accuracy, precision and selectivity of the proposed method which can be effectively used for the analysis of amoxapine in the presence of degradation products.

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Phytochemical, Analytical and Medicinal Studies of Holoptelea integrifolia Roxb. Planch - A Review

Current Traditional Medicine ◽

10.2174/2215083805666190521103308 ◽

2019 ◽

Vol 5 (4) ◽

pp. 270-277 ◽

Cited By ~ 2

Author(s):

Vijay Kumar ◽

Simranjeet Singh ◽

Ragini Bhadouria ◽

Ravindra Singh ◽

Om Prakash

Keyword(s):

Liquid Chromatography ◽

Thin Layer ◽

Thin Layer Chromatography ◽

High Performance ◽

Biologically Active ◽

Toxicological Studies ◽

Wide Range ◽

Layer Chromatography

Holoptelea integrifolia Roxb. Planch (HI) has been used to treat various ailments including obesity, osteoarthritis, arthritis, inflammation, anemia, diabetes etc. To review the major phytochemicals and medicinal properties of HI, exhaustive bibliographic research was designed by means of various scientific search engines and databases. Only 12 phytochemicals have been reported including biologically active compounds like betulin, betulinic acid, epifriedlin, octacosanol, Friedlin, Holoptelin-A and Holoptelin-B. Analytical methods including the Thin Layer Chromatography (TLC), High-Performance Thin Layer Chromatography (HPTLC), High-Performance Liquid Chromatography (HPLC) and Liquid Chromatography With Mass Spectral (LC-MS) analysis have been used to analyze the HI. From medicinal potency point of view, these phytochemicals have a wide range of pharmacological activities such as antioxidant, antibacterial, anti-inflammatory, and anti-tumor. In the current review, it has been noticed that the mechanism of action of HI with biomolecules has not been fully explored. Pharmacology and toxicological studies are very few. This seems a huge literature gap to be fulfilled through the detailed in-vivo and in-vitro studies.

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Improving the Organic Semiconductor- Metal Contact Interface in Printed High Performance Organic TFTs

MRS Proceedings ◽

10.1557/opl.2012.189 ◽

2012 ◽

Vol 1402 ◽

Author(s):

Kanan Puntambekar ◽

Lisa Stecker ◽

Kurt Ulmer ◽

Themistokles Afentakis ◽

Steven Droes

Keyword(s):

Organic Semiconductor ◽

High Performance ◽

Thin Film Transistor ◽

Device Performance ◽

Organic Thin Film ◽

Contact Interface ◽

Organic Thin Film Transistor ◽

Metal Electrodes ◽

Free Surfaces ◽

Gas Plasma

ABSTRACTOptimization of the interface between the organic semiconductor (OSC) & the source-drain (S/D) electrode is critical in order to improve organic thin film transistor (OTFT) device performance. This process typically involves coating the metal S/D electrodes with an optimal self-assembled thiol layer; a process that requires pristine metal surfaces for successful treatment. Obtaining contamination free surfaces can be challenging in the case of printed metal electrodes. Here we demonstrate an effective strategy to address this issue by introducing a brief low power forming gas plasma treatment prior to the surface coating step. We show a two orders of magnitude decrease in the contact resistance as a result of this treatment.

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RELaTED Project: New Developments on Ultra-Low Temperature District Heating Networks

Proceedings ◽

10.3390/proceedings2020065008 ◽

2020 ◽

Vol 65 (1) ◽

pp. 25

Author(s):

Antonio Garrido Marijuan ◽

Roberto Garay ◽

Mikel Lumbreras ◽

Víctor Sánchez ◽

Olga Macias ◽

...

Keyword(s):

Low Temperature ◽

High Performance ◽

Waste Heat ◽

District Heating ◽

Hot Water ◽

Thermal Systems ◽

Heating Source ◽

Wide Range ◽

Thermal Sources ◽

Heating Networks

District heating networks deliver around 13% of the heating energy in the EU, being considered as a key element of the progressive decarbonization of Europe. The H2020 REnewable Low TEmperature District project (RELaTED) seeks to contribute to the energy decarbonization of these infrastructures through the development and demonstration of the following concepts: reduction in network temperature down to 50 °C, integration of renewable energies and waste heat sources with a novel substation concept, and improvement on building-integrated solar thermal systems. The coupling of renewable thermal sources with ultra-low temperature district heating (DH) allows for a bidirectional energy flow, using the DH as both thermal storage in periods of production surplus and a back-up heating source during consumption peaks. The ultra-low temperature enables the integration of a wide range of energy sources such as waste heat from industry. Furthermore, RELaTED also develops concepts concerning district heating-connected reversible heat pump systems that allow to reach adequate thermal levels for domestic hot water as well as the use of the network for district cooling with high performance. These developments will be demonstrated in four locations: Estonia, Serbia, Denmark, and Spain.

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Applicability of Cork as Novel Modifiers to Develop Electrochemical Sensor for Caffeine Determination

Materials ◽

10.3390/ma14010037 ◽

2020 ◽

Vol 14 (1) ◽

pp. 37

Author(s):

Mayra K. S. Monteiro ◽

Djalma R. Da Silva ◽

Marco A. Quiroz ◽

Vítor J. P. Vilar ◽

Carlos A. Martínez-Huitle ◽

...

Keyword(s):

Electrochemical Sensor ◽

Linear Response ◽

High Performance ◽

Low Cost ◽

Pharmaceutical Formulations ◽

Caffeine Concentration ◽

Real Samples ◽

Wide Range ◽

Potential Use

This study aims to investigate the applicability of a hybrid electrochemical sensor composed of cork and graphite (Gr) for detecting caffeine in aqueous solutions. Raw cork (RAC) and regranulated cork (RGC, obtained by thermal treatment of RAC with steam at 380 °C) were tested as modifiers. The results clearly showed that the cork-graphite sensors, GrRAC and GrRGC, exhibited a linear response over a wide range of caffeine concentration (5–1000 µM), with R2 of 0.99 and 0.98, respectively. The limits of detection (LOD), estimated at 2.9 and 6.1 µM for GrRAC and GrRGC, suggest greater sensitivity and reproducibility than the unmodified conventional graphite sensor. The low-cost cork-graphite sensors were successfully applied in the determination of caffeine in soft drinks and pharmaceutical formulations, presenting well-defined current signals when analyzing real samples. When comparing electrochemical determinations and high performance liquid chromatography measurements, no significant differences were observed (mean accuracy 3.0%), highlighting the potential use of these sensors to determine caffeine in different samples.

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Review of Functional Treatments for Modified Wood

Coatings ◽

10.3390/coatings11030327 ◽

2021 ◽

Vol 11 (3) ◽

pp. 327

Author(s):

Morwenna J. Spear ◽

Simon F. Curling ◽

Athanasios Dimitriou ◽

Graham A. Ormondroyd

Keyword(s):

High Performance ◽

Responsive Materials ◽

Wood Modification ◽

Wide Range ◽

Natural Wood ◽

Impregnation Modification ◽

New Applications ◽

New Generation ◽

Dimensional Instability ◽

Modified Wood

Wood modification is now widely recognized as offering enhanced properties of wood and overcoming issues such as dimensional instability and biodegradability which affect natural wood. Typical wood modification systems use chemical modification, impregnation modification or thermal modification, and these vary in the properties achieved. As control and understanding of the wood modification systems has progressed, further opportunities have arisen to add extra functionalities to the modified wood. These include UV stabilisation, fire retardancy, or enhanced suitability for paints and coatings. Thus, wood may become a multi-functional material through a series of modifications, treatments or reactions, to create a high-performance material with previously impossible properties. In this paper we review systems that combine the well-established wood modification procedures with secondary techniques or modifications to deliver emerging technologies with multi-functionality. The new applications targeted using this additional functionality are diverse and range from increased electrical conductivity, creation of sensors or responsive materials, improvement of wellbeing in the built environment, and enhanced fire and flame protection. We identified two parallel and connected themes: (1) the functionalisation of modified timber and (2) the modification of timber to provide (multi)-functionality. A wide range of nanotechnology concepts have been harnessed by this new generation of wood modifications and wood treatments. As this field is rapidly expanding, we also include within the review trends from current research in order to gauge the state of the art, and likely direction of travel of the industry.

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Strength Analysis of Alternative Airframe Layouts of Regional Aircraft on the Basis of Automated Parametrical Models

Aerospace ◽

10.3390/aerospace8030080 ◽

2021 ◽

Vol 8 (3) ◽

pp. 80

Author(s):

Dmitry V. Vedernikov ◽

Alexander N. Shanygin ◽

Yury S. Mirgorodsky ◽

Mikhail D. Levchenkov

Keyword(s):

Aspect Ratio ◽

High Aspect Ratio ◽

High Performance ◽

Strength Analysis ◽

Labor Input ◽

Aerodynamic Loading ◽

Aspect Ratios ◽

Wide Range ◽

Parametrical Design

This publication presents the results of complex parametrical strength investigations of typical wings for regional aircrafts obtained by means of the new version of the four-level algorithm (FLA) with the modified module responsible for the analysis of aerodynamic loading. This version of FLA, as well as a base one, is focused on significant decreasing time and labor input of a complex strength analysis of airframes by using simultaneously different principles of decomposition. The base version includes four-level decomposition of airframe and decomposition of strength tasks. The new one realizes additional decomposition of alternative variants of load cases during the process of determination of critical load cases. Such an algorithm is very suitable for strength analysis and designing airframes of regional aircrafts having a wide range of aerodynamic concepts. Results of validation of the new version of FLA for a high-aspect-ratio wing obtained in this work confirmed high performance of the algorithm in decreasing time and labor input of strength analysis of airframes at the preliminary stages of designing. During parametrical design investigation, some interesting results for strut-braced wings having high aspect ratios were obtained.

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Towards a Glass New World: The Role of Ion-Exchange in Modern Technology

Applied Sciences ◽

10.3390/app11104610 ◽

2021 ◽

Vol 11 (10) ◽

pp. 4610

Author(s):

Simone Berneschi ◽

Giancarlo C. Righini ◽

Stefano Pelli

Keyword(s):

Ion Exchange ◽

Communication Networks ◽

High Speed ◽

High Performance ◽

Low Cost ◽

Modern Technology ◽

Historical Background ◽

Wide Range ◽

Happy Marriage

Glasses, in their different forms and compositions, have special properties that are not found in other materials. The combination of transparency and hardness at room temperature, combined with a suitable mechanical strength and excellent chemical durability, makes this material indispensable for many applications in different technological fields (as, for instance, the optical fibres which constitute the physical carrier for high-speed communication networks as well as the transducer for a wide range of high-performance sensors). For its part, ion-exchange from molten salts is a well-established, low-cost technology capable of modifying the chemical-physical properties of glass. The synergy between ion-exchange and glass has always been a happy marriage, from its ancient historical background for the realisation of wonderful artefacts, to the discovery of novel and fascinating solutions for modern technology (e.g., integrated optics). Getting inspiration from some hot topics related to the application context of this technique, the goal of this critical review is to show how ion-exchange in glass, far from being an obsolete process, can still have an important impact in everyday life, both at a merely commercial level as well as at that of frontier research.

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Novel Bloch wave excitation platform based on few-layer photonic crystal deposited on D-shaped optical fiber

Scientific Reports ◽

10.1038/s41598-021-90504-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Esteban Gonzalez-Valencia ◽

Ignacio Del Villar ◽

Pedro Torres

Keyword(s):

Optical Fibers ◽

High Performance ◽

Light Propagation ◽

Fiber Optic ◽

Layer Structure ◽

Optical Network ◽

Building Blocks ◽

Bloch Wave ◽

Nanophotonic Devices ◽

Wide Range

AbstractWith the goal of ultimate control over the light propagation, photonic crystals currently represent the primary building blocks for novel nanophotonic devices. Bloch surface waves (BSWs) in periodic dielectric multilayer structures with a surface defect is a well-known phenomenon, which implies new opportunities for controlling the light propagation and has many applications in the physical and biological science. However, most of the reported structures based on BSWs require depositing a large number of alternating layers or exploiting a large refractive index (RI) contrast between the materials constituting the multilayer structure, thereby increasing the complexity and costs of manufacturing. The combination of fiber–optic-based platforms with nanotechnology is opening the opportunity for the development of high-performance photonic devices that enhance the light-matter interaction in a strong way compared to other optical platforms. Here, we report a BSW-supporting platform that uses geometrically modified commercial optical fibers such as D-shaped optical fibers, where a few-layer structure is deposited on its flat surface using metal oxides with a moderate difference in RI. In this novel fiber optic platform, BSWs are excited through the evanescent field of the core-guided fundamental mode, which indicates that the structure proposed here can be used as a sensing probe, along with other intrinsic properties of fiber optic sensors, as lightness, multiplexing capacity and easiness of integration in an optical network. As a demonstration, fiber optic BSW excitation is shown to be suitable for measuring RI variations. The designed structure is easy to manufacture and could be adapted to a wide range of applications in the fields of telecommunications, environment, health, and material characterization.

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Robust Sensorless Model-Predictive Torque Flux Control for High-Performance Induction Motor Drives

Mathematics ◽

10.3390/math9040403 ◽

2021 ◽

Vol 9 (4) ◽

pp. 403

Author(s):

Ahmed G. Mahmoud A. Aziz ◽

Hegazy Rez ◽

Ahmed A. Zaki Diab

Keyword(s):

Induction Motor ◽

High Performance ◽

Core Loss ◽

Parameters Estimation ◽

Torque Control ◽

Flux Control ◽

Control Approach ◽

Light Load ◽

Wide Range ◽

Lyapunov’S Theorem

This paper introduces a novel sensorless model-predictive torque-flux control (MPTFC) for two-level inverter-fed induction motor (IM) drives to overcome the high torque ripples issue, which is evidently presented in model-predictive torque control (MPTC). The suggested control approach will be based on a novel modification for the adaptive full-order-observer (AFOO). Moreover, the motor is modeled considering core losses and a compensation term of core loss applied to the suggested observer. In order to mitigate the machine losses, particularly at low speed and light load operations, the loss minimization criterion (LMC) is suggested. A comprehensive comparative analysis between the performance of IM drive under conventional MPTC, and those of the proposed MPTFC approaches (without and with consideration of the LMC) has been carried out to confirm the efficiency of the proposed MPTFC drive. Based on MATLAB® and Simulink® from MathWorks® (2018a, Natick, MA 01760-2098 USA) simulation results, the suggested sensorless system can operate at very low speeds and has the better dynamic and steady-state performance. Moreover, a comparison in detail of MPTC and the proposed MPTFC techniques regarding torque, current, and fluxes ripples is performed. The stability of the modified adaptive closed-loop observer for speed, flux and parameters estimation methodology is proven for a wide range of speeds via Lyapunov’s theorem.

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