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1
White, J. W. "Flying Characteristics of the Transverse and Negative Pressure Contour (“TNP”) Slider Air Bearing". Journal of Tribology 119, n. 2 (1 aprile 1997): 241–48. http://dx.doi.org/10.1115/1.2833166.
Testo completoAbstract (sommario):
The TNP contour air bearing slider is composed of oversized transverse pressure contour (TPC) outer rails and a central negative pressure (NP) cavity. The NP cavity is separated from the TPC rails by an ambient pressure reservoir which serves two functions. First, it prevents direct hydrodynamic interaction between the various component air bearing surfaces and thus, eliminates pressure distortion and dilution, common causes of problems related to flying height and roll angle control. Second, the ambient reservoir allows the TPC rails and NP cavity to be configured and dimensioned independently so that they will track each other with a nearly constant force difference, resulting in a flying height that has significantly reduced sensitivity to altitude change. The multi-function TPC sections of the outside rails are able to overcome the effects of a changing radius and wide skew angle variation over the disk radius as well as a changing vacuum load and asymmetry of the NP cavity pressure, in order to provide a truly constant low flying height over the entire data surface. The combination of a high air bearing stiffness and a gradually developing cavity vacuum as disk velocity increases produces a rapid slider take-off from the disk surface. Dynamic stability of the TNP slider air bearing is enhanced by the unusual combination of a high air bearing stiffness and high air film damping in each of the three slider excursion modes. Finally, the TNP slider experiences a reduced sensitivity of flying height to manufacturing and operational tolerances as compared to non-NP type sliders. The entire TNP slider air bearing is created by a two-etch process. A shallow etch creates the TPC sections and leading edge step. A deeper etch forms the NP cavity, ambient pressure reservoir, and outermost edge of each side rail.
2
Kodagoda, Gethmini, Hung T. Hong, Tim J. O’Hare, Yasmina Sultanbawa, Bruce Topp e Michael E. Netzel. "Effect of Storage on the Nutritional Quality of Queen Garnet Plum". Foods 10, n. 2 (7 febbraio 2021): 352. http://dx.doi.org/10.3390/foods10020352.
Testo completoAbstract (sommario):
Due to high perishability, plums are harvested at an early stage of maturity to extend postharvest storage life. Storage time and temperature can significantly affect the phytochemical and sugar composition of plums, altering their palatability and nutritional quality. In this study, variations in physiochemical properties (total soluble solids (TSS), titratable acidity (TA), color (chroma and hue angle)), phytochemical composition (total phenolic content (TPC), total anthocyanin content (TAC), and carotenoids), and sugars in three different tissues of the Queen Garnet plum (QGP) during storage at two common domestic storage temperatures (4 and 23 °C) were evaluated. There was an increase (p > 0.05) in TSS and a reduction (p < 0.05) in TA of the outer flesh at 23 °C. Chroma values of all the tissues reduced (p < 0.05) at 23 °C. At 4 °C, chroma values fluctuated between storage days. The TAC of the peel was the highest (p < 0.05) among the different tissues and continued to increase up to 10 days of storage at 23 °C (3-fold increase). At 4 °C, the highest (p < 0.05) TAC (peel) was observed after 14 days of storage (1.2-fold increase). TPC showed similar results. The highest (p < 0.05) TPC was recorded in the peel after 10 days of storage at 23 °C (2.3-fold increase) and after 14 days of storage at 4 °C (1.3-fold increase), respectively. Total carotenoids in the flesh samples at both storage temperatures were reduced (p < 0.05) after 14 days. Total sugars also decreased during storage. The results of the present study clearly showed that common domestic storage conditions can improve the nutritional quality of plums by increasing the content of bioactive anthocyanins and other phenolic compounds. However, the increase in phytochemicals needs to be counterbalanced with the decrease in total sugars and TA potentially affecting the sensory attributes of the plums.
3
Jones, S. B., T. S. Nonnenmacher, E. Atkin, G. J. Barker, A. Basharina-Freshville, C. Betancourt, S. B. Boyd et al. "Off-Axis Characterisation of the CERN T10 Beam for low Momentum Proton Measurements with a High Pressure Gas Time Projection Chamber". Instruments 4, n. 3 (28 luglio 2020): 21. http://dx.doi.org/10.3390/instruments4030021.
Testo completoAbstract (sommario):
We present studies of proton fluxes in the T10 beamline at CERN. A prototype high pressure gas time projection chamber (TPC) was exposed to the beam of protons and other particles, using the 0.8 GeV/c momentum setting in T10, in order to make cross section measurements of low energy protons in argon. To explore the energy region comparable to hadrons produced by GeV-scale neutrino interactions at oscillation experiments, i.e., near 0.1 GeV of kinetic energy, methods of moderating the T10 beam were employed: the dual technique of moderating the beam with acrylic blocks and measuring scattered protons off the beam axis was used to decrease the kinetic energy of incident protons, as well as change the proton/minimum ionising particle (MIP) composition of the incident flux. Measurements of the beam properties were made using time of flight systems upstream and downstream of the TPC. The kinetic energy of protons reaching the TPC was successfully changed from ∼0.3 GeV without moderator blocks to less than 0.1 GeV with four moderator blocks (40 cm path length). The flux of both protons and MIPs off the beam axis was increased. The ratio of protons to MIPs vary as a function of the off-axis angle allowing for possible optimisation of the detector to select the type of required particles. Simulation informed by the time of flight measurements show that with four moderator blocks placed in the beamline, (5.6 ± 0.1) protons with energies below 0.1 GeV per spill traversed the active TPC region. Measurements of the beam composition and energy are presented.
4
Liu, Mengnan, Yu Han, Xiaoqi Xi, Linlin Zhu, Chang Liu, Siyu Tan, Jian Chen, Lei Li e Bin Yan. "Drift Artifacts Correction for Laboratory Cone-Beam Nanoscale X-ray Computed Tomography by Fitting the Partial Trajectory of Projection Centroid". Photonics 9, n. 6 (8 giugno 2022): 405. http://dx.doi.org/10.3390/photonics9060405.
Testo completoAbstract (sommario):
A self-correction method for the drift artifacts of laboratory cone-beam nanoscale X-ray computed tomography (nano-CT) based on the trajectory of projection centroid (TPC) is proposed. This method does not require additional correction phantoms, simplifying the correction process. The whole TPC is estimated by the partial TPC in the optimal projection set. The projection drift is calculated by the measured TPC and the estimated TPC. The interval search method is used so that the proposed method can adapt to the case of a truncated projection due to drift. The fixed-angle scanning experiment of the Siemens star and the partial derivative analysis of the projection position show the necessity of correcting drift artifacts. Further, the Shepp–Logan phantoms with different drift levels are simulated. The results show that the proposed method can effectively estimate the horizontal and vertical drifts within the projection drift range of ±2 mm (27 pixels) with high accuracy. Experiments were conducted on tomato seed and bamboo stick to validate the feasibility of the proposed method for samples with different textures. The correction effect on different reconstructed slices indicates that the proposed method provides performance superior to the reference scanning method (RSM) and global fitting. In addition, the proposed method requires no extra scanning, which improves the acquisition efficiency, as well as radiation utilization.
5
Soethe, Cristina, Cristiano André Steffens, Leonora Mansur Mattos, Nathalie Alcântara Ferreira e Daiane Michele Mayer. "Postharvest quality and functional compounds in "dedo-de-moça" 'BRS Mari' pepper fruit at different stages of maturity". Ciência Rural 46, n. 8 (29 aprile 2016): 1322–28. http://dx.doi.org/10.1590/0103-8478cr20141795.
Testo completoAbstract (sommario):
ABSTRACT: The purpose of this study was to evaluate the physicochemical characteristics and functional properties of "dedo-de-moça" 'BRS Mari' pepper fruits at different maturity stages, and determine the ideal harvest stage for fresh consumption. The pepper plants were grown in the experimental field of Embrapa Hortaliças (Brasília, DF, Brazil) in 2012, and their fruits were evaluated at 20, 30, 40, 50, 60, 70, and 80 days after anthesis (DAA) to determine the soluble solid content (SS), titratable acidity (TA), SS/TA ratio, color (hue angle and lightness), a, b, and total chlorophyll, total phenolic compounds (TPC), total antioxidant activity (TAA), and capsanthin. It was observed that SS content increased until 70 DAA, and TA increased until 50 DAA, with decrease at 80 DAA. The a and total chlorophyll decreased until 60 DAA. Values for chlorophyll b were high until 30 DAA, and then decreased. The values for hue angle and lightness decreased until 60 DAA, indicating a change from green to red in fruits external color, with small changes in color from 60 to 80 DAA. The TPC content increased until 60 DAA, and then small increases occurred until 80 DAA. The AA increased as the fruit ripened, and the capsanthin content increased until 70 DAA. These results indicated that the ideal stage for harvest of the "dedo-de-moça" 'BRS Mari' pepper fruits is at 70 days after anthesis, when they also have a full development of red color in the fruit epidermis.
6
SHAO, MING, e LIANG LI. "A STUDY ON THE INTRINSIC TIME RESOLUTION OF THE MRPC USED IN THE STAR-TOF". International Journal of Modern Physics E 16, n. 07n08 (agosto 2007): 2476–83. http://dx.doi.org/10.1142/s0218301307008124.
Testo completoAbstract (sommario):
Time-Of-Flight (TOF) based on Multi-gap Resistive Plate Chamber (MRPC) detectors have been successfully operating at the STAR experiment since 2003.2,3 The MRPC time resolution is however found to be significantly worse2 (80-90 ps) than that previously obtained in beam test (60 ps).4 In order to fully understand MRPC working principles and operating requirements, an extensive calibration study is performed using data collected by STAR in 200 GeV Au + Au collisions in 2004. The relation between MRPC timing, signal amplitude, incident angle and momentum are discussed. Contributions from tracking properties of STAR-TPC are also studied by simulation. The intrinsic time resolution of the MRPCs used in STAR-TOF, after taking all factors into consideration, is found to be in good agreement with beam test results.
7
Muzolf-Panek, Małgorzata, e Agnieszka Waśkiewicz. "Relationship between Phenolic Compounds, Antioxidant Activity and Color Parameters of Red Table Grape Skins Using Linear Ordering Analysis". Applied Sciences 12, n. 12 (16 giugno 2022): 6146. http://dx.doi.org/10.3390/app12126146.
Testo completoAbstract (sommario):
Color, being one of the most important sensory characteristics, could be associated to the phenolic compound content and/or the antioxidant activity of fruits and vegetables. In this study, linear ordering was used to build quality rankings of red table grapes based on color parameters or phenolic compounds. First, the principle component analysis (PCA) was used to show the association between color of red grape skins (evaluated in CIE L*a*b* and L*C*h systems) and their individual phenolic compounds (investigated by the HPLC), total polyphenol content (TPC), total anthocyanins (ACNs), as well as the antioxidant activity (DPPH) of five table grape varieties. It could be observed that the lightness (L*) and hue angle (h) are the color coordinates strongly related to some phenolic compounds and ACN, whereas a* was related to DPPH and TPC. Five distinct clusters could be observed from PCA analysis with dark-colored grape varieties showing high levels of ACN (3.48–5.83 mg/g), low lightness (47.8–53.0), and high h values (353.7–359.8°). L*, a*, and h color coordinates were used to build table grape ranking. The second ranking was built based on phenolic compound content. Results of the two rankings were correlated. High Tau Kendall correlation coefficient (0.51, p = 0.000) indicated that linear ordering analysis, based on the simple color measurements, could be a useful tool for rapid screening of the quality of grapes. This could be valuable information for producers and consumers of the fruit making decision on the market.
8
Kumar, Abhinay, Rajan Choudhary e Ankush Kumar. "Aging characteristics of asphalt binders modified with waste tire and plastic pyrolytic chars". PLOS ONE 16, n. 8 (19 agosto 2021): e0256030. http://dx.doi.org/10.1371/journal.pone.0256030.
Testo completoAbstract (sommario):
Globally, the growing volume of waste tires and plastics has posed significant concerns about their sustainable and economical disposal. Pyrolysis provides a way for effective treatment and management of these wastes, enabling recovery of energy and produces solid pyrolytic char as a by-product. The use of pyrolytic chars in asphalt binder modification has recently gained significant interest among researchers. As asphalt binder aging influences the cracking, rutting, and moisture damage performance of asphalt binder and the mixtures, evaluation of aging characteristics of char modified asphalt binders is quite important. The main objective of this study is the investigation of the aging characteristics of asphalt binders modified with waste tire pyrolytic char (TPC) and waste plastic pyrolytic char (PPC) through rheological and spectroscopic evaluations. To imitate short-term and long-term aging conditions, the asphalt binders were first treated in a rolling thin film oven (RTFO) and then in a pressure aging vessel (PAV). The aging characteristics were determined using four rheological aging indices based on complex modulus (G*), phase angle (δ), zero shear viscosity (ZSV), and non-recoverable creep compliance (Jnr) from multiple stress creep and recovery (MSCR) test. The fatigue cracking potential was then measured through binder yield energy test (BYET). These parameters were measured through a dynamic shear rheometer. Fourier transform infrared (FTIR) and proton nuclear magnetic resonance (1H-NMR) spectroscopy analyses were then used to investigate changes in chemical composition due to aging in the char modified binders. Both TPC and PPC improved the high-temperature deformation resistance properties of asphalt binder. The TPC-modified binder showed better aging resistance than the control and PPC-modified binders, based on the different rheological and spectroscopic indices. The pyrolytic char modified binders also demonstrated good fatigue performance.
9
Zhao, Xianli, Wei Liu, Cong Li, Gang Yan, Qianwen Wang, Li Yang e Yichun Zhou. "Solid Particle Erosion Behavior of La2Ce2O7/YSZ Double-Ceramic-Layer and Traditional YSZ Thermal Barrier Coatings at High Temperature". Coatings 12, n. 11 (28 ottobre 2022): 1638. http://dx.doi.org/10.3390/coatings12111638.
Testo completoAbstract (sommario):
Thermal barrier coatings (TBC) used for turbine blades are indispensable for the most advanced aero-engines due to their excellent thermal insulation performance. Solid particle erosion (SPE) at high temperatures is one of the most critical factors in TBC failure. The high-temperature SPE failure behavior of TBC on circular sheets and turbine blades was investigated in this paper at erosion angles 60° and 90°. The high-temperature thermal shock behavior of TBC was also studied as the control group. The SPE failure mechanism of TBC is attributed to the spallation and thickness decrease of TBC. The formation of thermally grown oxide is the main reason for the TBC spallation, while the thickness decrease of TBC is due to the impaction of solid particles by near-surface cracking. The erosion angle is critical to the failure behavior of TBC, and TBC is more susceptible to SPE at an erosion angle of 60° than that at 90° because of the additional shear stress. Furthermore, a La2Ce2O7/YSZ double-ceramic-layer TBC was designed and deposited on turbine blades. The experimental results indicate that this type of double-layer TBC has more excellent performance under SPE than traditional YSZ TBC.
10
Fang, T.-G., R. E. Coverdill, C.-F. F. Lee e R. A. White. "Low-sooting combustion in a small-bore high-speed direct-injection diesel engine using narrow-angle injectors". Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 222, n. 10 (1 ottobre 2008): 1927–37. http://dx.doi.org/10.1243/09544070jauto751.
Testo completoAbstract (sommario):
An optically accessible high-speed direct-injection diesel engine was used to study the effects of injection angles on low-sooting combustion. A digital high-speed camera was employed to capture the entire cycle combustion and spray evolution processes under seven operating conditions including post-top-dead centre (TDC) injection and pre-TDC injection strategies. The nitrogen oxide (NO x) emissions were also measured in the exhaust pipe. In-cylinder pressure data and heat release rate calculations were conducted. All the cases show premixed combustion features. For post-TDC injection cases, a large amount of fuel deposition is seen for a narrower-injection-angle tip, i.e. the 70° tip, and ignition is observed near the injector tip in the centre of the bowl, while for a wider-injection-angle tip, namely a 110° tip, ignition occurs near the spray tip in the vicinity of the bowl wall. The combustion flame is near the bowl wall and at the central region of the bowl for the 70° tip. However, the flame is more distributed and centralized for the 110° tip. Longer spray penetration is found for the pre-TDC injection timing cases. Liquid fuel impinges on the bowl wall or on the piston top and a fuel film is formed. Ignition for all the pre-TDC injection cases occur in a distributed way in the piston bowl. Two different combustion modes are observed for the pre-TDC injection cases including a homogeneous bulky combustion flame at earlier crank angles and a heterogeneous film combustion mode with luminous sooting flame at later crank angles. In terms of soot emissions, NO x emissions, and fuel efficiency, results show that the late post-TDC injection strategy gives the best performance.
11
Liu, Jiajia, Jianmin Hu, Mengqi Shen, Ming Yang e Yingxiang Fang. "LNMR Study on Microstructure Characteristics and Pore Size Distribution of High-Rank Coals with Different Bedding". Advances in Civil Engineering 2021 (7 ottobre 2021): 1–8. http://dx.doi.org/10.1155/2021/8542630.
Testo completoAbstract (sommario):
In order to study the pore structure characteristics of high-rank coals with different bedding, NMR experiments were carried out for high-rank coals with different bedding angles (0°, 30°, 45°, 60°, and 90°). The results show that the distribution of T2 map of high-rank coal with different bedding is similar to some extent, showing a double peak or triple peak distribution, and the first peak accounts for more than 97% of the total, indicating that small holes are developed in high-rank coal with different bedding, while macropores are not developed. The influence of bedding angle on the fracture proportion is less than 0.3%. Compared with the fracture proportion, the effect of bedding angle on the proportion of microhole, medium hole, and large hole is greater and presents a certain rule. There are certain differences in T2 cutoff value (T2C) of high-rank coal with different bedding. The relationship between bedding angle and T2C conforms to exponential function, and the correlation degree R2 is 0.839. The research results provide a theoretical basis for gas extraction and utilization and prevention of gas disaster in coal mines in China.
12
Xu, Bin, Li Luo, Jian Wu e Zhi Hao Ma. "The Influence of Injection Timing on Emissions Characteristics of a DI Diesel Engine Fuelled with Pistacia Chinensis Bunge Seed Biodiesel". Advanced Materials Research 634-638 (gennaio 2013): 846–51. http://dx.doi.org/10.4028/www.scientific.net/amr.634-638.846.
Testo completoAbstract (sommario):
The effect of various fuel injection advance angles on the emissions of an electronically controlled, high pressure, common rail, turbocharged GW4D20 diesel engine fuelled with different pistacia chinensis bunge seed biodiesel/diesel blends has been experimentally investigated. The results indicate that brake specific fuel consumption reduces with the increasing of fuel injection advance angle, and the BSFC of blends is higher than diesel. At 25% load, CO and THC are significantly reduced compared with higher load. The CO emission increases with the increment of fuel injection advance angle. At 75% load, the CO of B10 is lowest, B20 highest. At the same speed, NOx increases with increment of fuel injection advance angle for diesel and biodiesel blends dramatically. However, NOx of blends and diesel are deteriorated at high load, but there are no obvious differences among them.
13
RENAULT, G., B. S. NIELSEN, J. WESTERGAARD e J. J. GAARDHØJE. "THE LASER OF THE ALICE TIME PROJECTION CHAMBER". International Journal of Modern Physics E 16, n. 07n08 (agosto 2007): 2413–18. http://dx.doi.org/10.1142/s0218301307008021.
Testo completoAbstract (sommario):
The large TPC (95 m3) of the ALICE detector at the CERN LHC was commissioned in summer 2006. The first tracks were observed both from the cosmic ray muons and from the laser rays injected into the TPC. In this article the basic principles of operating the 266 nm lasers are presented, showing the installation and adjustment of the optical system and describing the control system. To generate the laser tracks, a wide laser beam is split into several hundred narrow beams by fixed micro-mirrors at stable and known positions throughout the TPC. In the drift volume, these narrow beams generate straight tracks at many angles. Here we describe the generation of the first tracks and compare them with simulations.
14
Angling, Matthew J., Sean Elvidge e Sean B. Healy. "Improved model for correcting the ionospheric impact on bending angle in radio occultation measurements". Atmospheric Measurement Techniques 11, n. 4 (18 aprile 2018): 2213–24. http://dx.doi.org/10.5194/amt-11-2213-2018.
Testo completoAbstract (sommario):
Abstract. The standard approach to remove the effects of the ionosphere from neutral atmosphere GPS radio occultation measurements is to estimate a corrected bending angle from a combination of the L1 and L2 bending angles. This approach is known to result in systematic errors and an extension has been proposed to the standard ionospheric correction that is dependent on the squared L1 ∕ L2 bending angle difference and a scaling term (κ). The variation of κ with height, time, season, location and solar activity (i.e. the F10.7 flux) has been investigated by applying a 1-D bending angle operator to electron density profiles provided by a monthly median ionospheric climatology model. As expected, the residual bending angle is well correlated (negatively) with the vertical total electron content (TEC). κ is more strongly dependent on the solar zenith angle, indicating that the TEC-dependent component of the residual error is effectively modelled by the squared L1 ∕ L2 bending angle difference term in the correction. The residual error from the ionospheric correction is likely to be a major contributor to the overall error budget of neutral atmosphere retrievals between 40 and 80 km. Over this height range κ is approximately linear with height. A simple κ model has also been developed. It is independent of ionospheric measurements, but incorporates geophysical dependencies (i.e. solar zenith angle, solar flux, altitude). The global mean error (i.e. bias) and the standard deviation of the residual errors are reduced from -1.3×10-8 and 2.2×10-8 for the uncorrected case to -2.2×10-10 rad and 2.0×10-9 rad, respectively, for the corrections using the κ model. Although a fixed scalar κ also reduces bias for the global average, the selected value of κ (14 rad−1) is only appropriate for a small band of locations around the solar terminator. In the daytime, the scalar κ is consistently too high and this results in an overcorrection of the bending angles and a positive bending angle bias. Similarly, in the nighttime, the scalar κ is too low. However, in this case, the bending angles are already small and the impact of the choice of κ is less pronounced.
15
Liu, Zhaofeng, Guiru Zhu, Yulin Wei, Dapeng Zhang, Lei Jiang, Haizeng Wang e Congjie Gao. "Enhanced flux performance of polyamide composite membranes prepared via interfacial polymerization assisted with ethyl formate". Water Science and Technology 76, n. 7 (22 giugno 2017): 1884–94. http://dx.doi.org/10.2166/wst.2017.349.
Testo completoAbstract (sommario):
A novel thin film composite (TFC) polyamide reverse osmosis membrane was prepared via the interfacial polymerization of m-phenylene diamine (MPD) in aqueous phase and 1,3,5-trimesoyl chloride (TMC) in organic phase on a polysulfone ultrafiltration support by assisting with ethyl formate as a co-solvent added in the organic phase. The ethyl formate added in the organic phase is intended to form a narrow miscibility zone, which leads to the thicker reaction zone. The multi-layered loose polyamide structure with larger pore size was formed due to the thicker reaction zone and lower content of MPD. The enhanced hydrophilicity of the membrane was proved by the decreased water contact angle. Water flux was measured at 1.6 MPa with 2,000 ppm NaCl aqueous solution. Compared to the TFC membrane prepared without ethyl formate, the water flux across the TFC membrane with ethyl formate in the organic phase increased with the increased ethyl formate content (from 23 to 45 L/(m2 h)) and the salt rejection remained at a high level (>90%). The ethyl formate can be used as a co-solvent to effectively enhance the performance of the TFC membrane.
16
Abu Seman, Mazrul Nizam, Nora’aini Ali, Nurul Ain Jalanni, Che Ku Muhammad Faizal Che Ku Yahya e Norhafiza Ilyana Yatim. "Characterization Assessment on Nanofiltration Membrane using Steric-Hindrance Pore (SHP) and Teorell-Meyer-Sievers (TMS) Models". Sains Malaysiana 52, n. 3 (31 marzo 2023): 941–51. http://dx.doi.org/10.17576/jsm-2023-5203-18.
Testo completoAbstract (sommario):
Interfacial polymerization (IP) is a simple process for modifying thin-film composite (TFC) polymers that can be used as separation membranes in water treatment. This work describes the IP process for the preparation of polyester TFC membranes using organic monomers, in particular triethanolamine (TEOA) and trimesoyl chloride (TMC). This work includes an evaluation of monomer concentration and polymerization reaction time as variables to determine the membrane properties and its performance as acid humic removal. The characterization of TFC membranes was investigated using field emission scanning electron microscopy (FESEM), steric hindrance pore (SHP) and Teorell-Meyer-Sievers model (TMS). This IP technique resulted in the membrane (NF-PES8-35) having the lowest contact angle (θ=34.0±0.35) and lower hydrophobicity (θ=62.6 ± 0.33) compared to the unmodified membrane. The rejection of NaCl by NF-PES8-35 membrane showed the highest 0.001 M NaCl (62.42%), while NF-PES4-15 membrane showed the lowest (2.4%). The highest removal of humic acid (97.8%) was achieved when separation was performed with the NF-PES6-35 membrane and the high performance polyester TFC membranes were exhibited in the water purification filtration system.
17
Al-Furaiji, Mustafa, Mohammed Kadhom, Khairi Kalash, Basma Waisi e Noor Albayati. "Preparation of thin-film composite membranes supported with electrospun nanofibers for desalination by forward osmosis". Drinking Water Engineering and Science 13, n. 2 (28 ottobre 2020): 51–57. http://dx.doi.org/10.5194/dwes-13-51-2020.
Testo completoAbstract (sommario):
Abstract. The forward osmosis (FO) process has been considered to be a viable option for water desalination in comparison to the traditional processes like reverse osmosis, regarding energy consumption and economical operation. In this work, a polyacrylonitrile (PAN) nanofiber support layer was prepared using the electrospinning process as a modern method. Then, an interfacial polymerization reaction between m-phenylenediamine (MPD) and trimesoyl chloride (TMC) was carried out to generate a polyamide selective thin-film composite (TFC) membrane on the support layer. The TFC membrane was tested in FO mode (feed solution facing the active layer) using the standard methodology and compared to a commercially available cellulose triacetate membrane (CTA). The synthesized membrane showed a high performance in terms of water flux (16 Lm −2 h−1) but traded the salt rejection (4 gm−2 h−1) compared with the commercial CTA membrane (water flux = 13 Lm−2 h−1 and salt rejection = 3 gm−2 h−1) at no applied pressure and room temperature. Scanning electron microscopy (SEM), contact angle, mechanical properties, porosity, and performance characterizations were conducted to examine the membrane.
18
Li, Bin, Zong De Liu, Yong Chen e Li Ping Zhao. "Erosion Resistance of TiC/Fe Composite at High Temperatures". Advanced Materials Research 79-82 (agosto 2009): 1087–90. http://dx.doi.org/10.4028/www.scientific.net/amr.79-82.1087.
Testo completoAbstract (sommario):
With an aim to investigate erosion properties, TiC/Fe composites fabricated by self -propagating high-temperature synthesis and pseudo heat isostatic pressing (SHS/PHIP) technique were studied experimentally. Phase composition, microstructure, composition and microhardness of the products are analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and microhardness tester, respectively. The elevated temperature erosion tests of the TiC/Fe composites were tested with the help of a GW/CS-MS type tester using SiO2 quartz and Al2O3 corundum as the abrasive. The influences of the different parameters such as impact angle, environment temperature, abrasive, on the erosion property of the TiC/Fe composites were studied. The morphology of the worn surface was analyzed with SEM to determine the erosion mechanisms.
19
Susanty, Hilda, Eli Ratni e Sofa Sopiah. "Subclinical Mastitis Prevalence of Dairy Goat Smallholder Farm and Total Plate Count of the Milk". Andalasian Livestock 1, n. 1 (29 gennaio 2024): 44–50. http://dx.doi.org/10.25077/alive.v1.n1.p44-50.2024.
Testo completoAbstract (sommario):
Subclinical mastitis is an inflammatory condition of the mammary gland without visible symptoms in dairy livestock. The subclinical mastitis should be detected periodically in every farm. This study aimed to determine the prevalence of subclinical mastitis in dairy goats on smallholder farms, followed by calculating the goat milk's total plate count (TPC) and pH value. Risk factors thought to cause subclinical mastitis on that farm are traditional livestock rearing techniques and land area that exceeds livestock capacity. The method used was a survey at a smallholder farm and laboratory analysis for the milk quality as a case study of a goat farm in Padang City, West Sumatra, Indonesia. The farm kept 118 goats from different breeds: Ettawa breeders, Sapera, Anglo Nubian, Anglo Sapera, and Anglo Saperaboer. Eighteen dairy goats were in the lactation period in June-July 2023. The results of subclinical mastitis examination of dairy goats were categorized as negative (-), positive 1 (+), positive 2 (++), and positive 3 (+++). The results showed that the prevalence of subclinical mastitis on that farm was 66.7%. Furthermore, milk TPC values (CFU/ml) were 3.1x105 (-), 5.6x106 (+), 9.9x106 (++), and 1.5x107 (+++). The pH values of the milk ranged from about 6.9 to 7.1. In conclusion, there was a high prevalence of subclinical mastitis on the farm. As such, the TPC and pH values were above the Indonesian National Standard for fresh milk quality.
20
Liu, Jing Jing, Zong De Liu e Li Ping Zhao. "Erosion Behavior of TiC-xNi Composite Coatings In Situ Synthesized by Electro-Thermal Explosion Ultra-High Speed Spraying". Advanced Materials Research 33-37 (marzo 2008): 1277–82. http://dx.doi.org/10.4028/www.scientific.net/amr.33-37.1277.
Testo completoAbstract (sommario):
With aim to investigate the effect of the content of Ni on erosion behavior of the TiC-xNi coating at elevated temperatures, The TiC-xNi (x=0, 5, 10, 15 , 20wt.%) composite coatings were in-situ synthesized on nickel-based alloy substrate by the self-developed electro-thermal explosion ultra-high speed spraying (EEUSS) device with the cored wire. Erosion properties of the coatings were assessed by the erosion tester under 90° incidence angle and 650°C. X-ray diffraction (XRD) and microhardness tester were used to investigate the coating phases and microhardness. The coatings consisted of TiC phase and Ni binder phase, as well as the residual C. The microhardness of TiC-xNi coating with the Ni content from 5 wt.% to 20wt.% decreased with the increase of the content of Ni. Elevated temperature erosion test indicate that the spiculate quartz particles impact the surface of the coating which lead to the loss of material. The erosion resistance of the TiC-xNi coatings increased first and decreased afterwards with the increase of the content of Ni. The relative erosion resistance of coating with 10 wt.% Ni addition is excellent which is about 2 times than that of TiC-20Ni coating under 650°C and 90° incidence angle.
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ZHANG, S., X. L. BUI, Y. FU e H. DU. "DEVELOPMENT OF CARBON-BASED COATING OF EXTREMELY HIGH TOUGHNESS WITH GOOD HARDNESS". International Journal of Nanoscience 03, n. 04n05 (agosto 2004): 571–78. http://dx.doi.org/10.1142/s0219581x04002395.
Testo completoAbstract (sommario):
Metallic Al was doped into amorphous carbon (a-C) to form a matrix of a-C(Al) of very low residual stress and high toughness at the expense of some hardness. Nanocrystallites of TiC (nc-TiC) of a few nanometers in size were embedded in this matrix to bring back the hardness. The nanocomposite coating of nc-TiC/a-C(Al) was deposited via co-sputtering of graphite, Ti , and Al targets. Although the nanocomposite coating exhibited a moderately high hardness (about 20 GPa), it possessed extremely high toughness (about 55% of plasticity during indentation deformation) and low residual stress (less than 0.4 GPa), smooth (Ra=5.5 nm ), and hydrophobic surface (contact angle with water reaches 100°).
22
Ahn, Geunseon, Jun-Young Kim, Jin-Hyung Shim, Sang-Hyun An, Junsik Kim, Changhwan Kim, In-Gyu Lee, Jung-Min Shin e Byunghoon Lee. "Three-Dimensional Printed Customized Scaffolds Covered with Decellularized Bone Extracellular Matrix for Open-Wedge High-Tibial Osteotomy". Bioengineering 11, n. 11 (8 novembre 2024): 1129. http://dx.doi.org/10.3390/bioengineering11111129.
Testo completoAbstract (sommario):
Void fillers are required for osseous gaps generated after orthopedic procedures as medial open-wedge high-tibial osteotomy (MOWHTO) to provide sufficient structural support and a rapid osteosynthesis. We developed a novel three-dimensional (3D) printing-based platform technology using the customized 3D scaffolds covered with polycaprolactone (PCL)/β-tri-calcium phosphates (β-TCP)/bone decellularized extracellular matrix (dECM) for use as bone substitute scaffold, which can be effectively exploited to estimate the calculated correction angle with preoperative simulations. PCL/β-TCP/bone dECM scaffolds demonstrated significantly higher cell contain levels in cell seeding efficiency, excellent proliferation capacity, and promotion of early osteogenic differentiation compared with PCL/β-TCP scaffolds. The scaffolds promoted bone mineralization at the early time points of an in vivo study (8 weeks) and exhibited biodegradable properties (38% for 16 weeks). The correction angle measured after osteotomy using 3D printed scaffolds was estimated with high accuracy with low errors (10.3° ± 0.9°) and was not significantly different even in the presence of lateral cortical hinge fractures. The customized 3D scaffold enriched with PCL/β-TCP/bone dECM yielded excellent cell seeding efficiency, proliferation capacity, early osteogenic differentiation, and bone mineralization outcomes. It is expected to solve the disadvantages related to bone union in MOWHTO and to replace autografts in the future.
23
Zhang, W., M. L. Sui, Y. Z. Zhou, J. D. Guo, G. H. He e D. X. Li. "Evolution of microstructure in TiC/NiCr cermet induced by electropulsing". Journal of Materials Research 18, n. 7 (luglio 2003): 1543–50. http://dx.doi.org/10.1557/jmr.2003.0213.
Testo completoAbstract (sommario):
Microstructures of a TiC/Ni80Cr20 cermet, subjected to single high-current-density electropulsing, were characterized by x-ray diffraction, transmission electron microscopy, and high-resolution transmission electron microscopy. Under the electropulsing, the shift of NiCr peaks versus the reverse change of TiC counterparts illustrates that the treatment gives rise to strong thermal stress impacting on the cermet. The stress, accompanied by the transient rise of temperature, led to microstructural evolutions of the cermet. Some nanostructured TiC grains, consisting of many nanocrystallites with small-angle grain boundaries, developed during electropulsing. Also, many regions teemed with coexisting nanosized TiC and NiCr crystallites, which possessed good bonding. Within the NiCr regions, large amounts of deformation twins were produced by the electropulsing.
24
Adesta, Erry Yulian Triblas, Muataz Al Hazza, Delvis Agusman e Agus Geter Edy Sutjipto. "Development of Tooling Cost Model for High Speed Hard Turning". Advanced Materials Research 418-420 (dicembre 2011): 1482–85. http://dx.doi.org/10.4028/www.scientific.net/amr.418-420.1482.
Testo completoAbstract (sommario):
The current work presents the development of cost model for tooling during high speed hard turning of AISI 4340 hardened steel using regression analysis. A set of experimental data using ceramic cutting tools, composed approximately of Al2O3 (70%) and TiC (30%) on AISI 4340 heat treated to a hardness of 60 HRC was obtained in the following design boundary: cutting speeds (175-325 m/min), feed rate (0.075-0.125 m/rev), negative rake angle (0 to -12) and depth of cut of (0.1-0.15) mm. The output data is used to develop a new model in predicting the tooling cost using in terms of cutting speed, feed rate, depth of cut and rake angle. Box Behnken Design was used in developing the model. Predictive regression model was found to be capable of good predictions the tooling cost within the boundary design.
25
Wang, Yuchao, Hui Wang, Dexin Zou e Huixuan Fu. "Ship Roll Prediction Algorithm Based on Bi-LSTM-TPA Combined Model". Journal of Marine Science and Engineering 9, n. 4 (6 aprile 2021): 387. http://dx.doi.org/10.3390/jmse9040387.
Testo completoAbstract (sommario):
When ships sail on the sea, the changes of ship motion attitude presents the characteristics of nonlinearity and high randomness. Aiming at the problem of low accuracy of ship roll angle prediction by traditional prediction algorithms and single neural network model, a ship roll angle prediction method based on bidirectional long short-term memory network (Bi-LSTM) and temporal pattern attention mechanism (TPA) combined deep learning model is proposed. Bidirectional long short-term memory network extracts time features from the forward and reverse of the ship roll angle time series, and temporal pattern attention mechanism extracts the time patterns from the deep features of a bidirectional long short-term memory network output state that are beneficial to ship roll angle prediction, ignore other features that contribute less to the prediction. The experimental results of real ship data show that the proposed Bi-LSTM-TPA combined model has a significant reduction in MAPE, MAE, and MSE compared with the LSTM model and the SVM model, which verifies the effectiveness of the proposed algorithm.
26
Feijoo, Iria, Pedro Merino, Gloria Pena, Pilar Rey e Marta Cabeza. "Microstructure and Mechanical Properties of an Extruded 6005A Al Alloy Composite Reinforced with TiC Nanosized Particles and Strengthened by Precipitation Hardening". Metals 10, n. 8 (4 agosto 2020): 1050. http://dx.doi.org/10.3390/met10081050.
Testo completoAbstract (sommario):
High-energy ball milling was carried out to disperse 3 vol% TiC nanoparticles (ex situ reinforcement) in a high-pressure inert gas-atomised prealloyed micron-sized 6005A Al alloy (AA6005A), with a Si/Mg atomic ratio of 1.32 powder matrix. Nanocomposite powders were consolidated by hot extrusion in strip shape at 500 °C, followed by a T6 ageing heat treatment. The microstructural features of the consolidated and precipitation hardening nanocomposites specimens were studied using X-ray diffractometry (DRX), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and electron backscatter diffraction (EBSD). The consolidated nanocomposites consisted of approximately equiaxed grains of different grain sizes with a high fraction of high-angle grain boundaries with average misorientation angles of approximately 35°. The nanocomposites showed remarkably higher hardness, Young’s modulus, yield, and ultimate strengths at room temperature than the extruded profiles of unreinforced milled AA6005A powders obtained through refinement of the Al alloy grain structure and a strong particle–matrix bonding, although with a drop in their ductility. The consolidated nanocomposite showed a weak response to industrial ageing heat treatment, as demonstrated by microstructural analyses and mechanical tests.
27
Durlu, Nuri, Nan Yao, David L. Milius e Ilhan A. Aksay. "Liquid-phase sintering of BN doped Fe-Cu/TiC composites". Proceedings, annual meeting, Electron Microscopy Society of America 54 (11 agosto 1996): 666–67. http://dx.doi.org/10.1017/s0424820100165793.
Testo completoAbstract (sommario):
Fe-Cu composites are commonly produced by liquid phase sintering (above the melting temperature of Cu, 1085°C). The wear resistance of these Fe-Cu alloys can be enhanced by introducing hard particles, e.g., TiC, into the matrix. In such cases, however, the densification of Fe-Cu/TiC composites by liquid phase sintering becomes difficult mainly due to the high wetting angle (110° at 1100-1200°C in argon) of liquid Cu with TiC particles. Especially when the amount of the TiC phase is high enough to form a continuous network of TiC grains, full densification is only achieved through hot pressing. We have recently overcome this problem in an [(Fe-4 wt% Cu) + 30 wt% TiC] composite by the addition of small amounts of BN. Composites with BN additives have been successfully sintered at 1275°C under vacuum or argon by additions of 1 wt% BN. Electron microscopic characterization of these composites has shown that this success is due to the modification of the liquid phase by the addition of BN, which also promotes the liquid phase sintering of the TiC phase.
28
Solnař, Stanislav, Jan Medek, Abubakar Shola Suleiman e Patrik Vyhlídal. "On a static and dynamic calibration of thermochromic liquid crystals". Acta Polytechnica 61, n. 4 (31 agosto 2021): 562–69. http://dx.doi.org/10.14311/ap.2021.61.0562.
Testo completoAbstract (sommario):
The paper deals with a static and dynamic calibration of selected wide-range thermochromic liquid crystals (TLC - SolarDust 24C), which are very easy to ingest and can provide accurate information on the temperature distribution on different surfaces. Static calibration problems, such as TLC illumination angle or illumination intensity, are solved and conclusions are drawn for the application of such a measurement. Dynamic experiments also indicate a certain time delay (around 50 ms) of the applied TLC measurement layer, which is very important to know for dynamic experimental methods, but the error and inaccuracy of the experiment is too high to draw conclusions.
29
Presby, Michael J., Jamesa L. Stokes, Bryan J. Harder, Kang N. Lee e Leland C. Hoffman. "High-Temperature Solid Particle Erosion of Environmental and Thermal Barrier Coatings". Coatings 13, n. 5 (10 maggio 2023): 902. http://dx.doi.org/10.3390/coatings13050902.
Testo completoAbstract (sommario):
Solid particle erosion (SPE) is a common phenomenon observed in gas turbine engines. Particles entrained in the gas flow impact engine hardware, resulting in micro-scale damage that leads to deleterious effects such as material removal. For protective coatings, damage due to SPE is a key concern, since it can negatively affect the durability of the coating and subsequently the life of the underlying component. In this work, the high-temperature SPE behavior of two state-of-the-art environmental barrier coatings (EBCs) deposited via air plasma spray (APS) is investigated using alumina erodent to understand the effect of particle kinetic energy, impingement angle, and temperature. The SPE behavior of the EBCs is also compared to APS and electron beam–physical vapor deposition (EB-PVD) thermal barrier coatings (TBCs) to elucidate similarities and differences in the erosion response. The EBCs were more susceptible to SPE than the EB-PVD TBC but had greater SPE resistance compared to the APS TBC. Coating microstructure and porosity were shown to have a strong influence on the observed behavior.
30
Kotlhao, Kate, Isiaka A. Lawal, Richard M. Moutloali e Michael J. Klink. "Antifouling Properties of Silver-Zinc Oxide Polyamide Thin Film Composite Membrane and Rejection of 2-Chlorophenol and 2,4-Dichlorophenol". Membranes 9, n. 8 (5 agosto 2019): 96. http://dx.doi.org/10.3390/membranes9080096.
Testo completoAbstract (sommario):
The silver-zinc oxide (Ag-ZnO) polyamide thin film composite (PA-TFC) membrane was prepared by interfacial polymerization. The Ag-ZnO/PA-TFC membrane was characterized by attenuated total reflectance fourier-transform infrared spectroscopy (ATR-FTIR) for polyamide functional groups and contact angle for surface hydrophilicity. The Ag-ZnO/PA-TFC membrane was further characterized by Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) for morphology and surface roughness, respectively. The performance of the fabricated membrane was investigated using pure water flux, permeability, rejection, flux recovery, and fouling resistance using low molecular weight organic pollutants, 2-chlorophenol (2-CP) and 2,4-dichlorophenol (2,4-DCP). The results were compared to the neat (PA-TFC) membrane. It was observed that incorporation of Ag-ZnO nanocomposites into the PA-TFC membrane improved hydrophilicity, permeation, rejection, and fouling resistance properties of the membrane. The contact angle decreased from 62.8° to 54° for PA-TFC and the Ag-ZnO/PA-TFC membrane, respectively. The presence of Ag-ZnO enhanced permeability of the membrane from 0.9 (Lm−2h−1bar−1) to 1.9 (Lm−2h−1bar−1). Modification of the membrane with Ag-ZnO further showed an enhanced rejection of 2-CP and 2,4-DCP from 43% to 80% and 58% to 85%, respectively. The 2,4-DCP molecules were rejected more than 2-CP due to enhanced repulsive forces from the extra Cl ion. A high flux recovery of about 95% was achieved for the modified membrane compared to 64% for the neat membrane. The improved flux recovery was an indication of enhanced antifouling propensity.
31
Gilles, Ralph, Debashis Mukherji, Lukas Karge, Pavel Strunz, Premysl Beran, Bruno Barbier, Armin Kriele, Michael Hofmann, Helmut Eckerlebe e Joachim Rösler. "Stability of TaC precipitates in a Co–Re-based alloy being developed for ultra-high-temperature applications". Journal of Applied Crystallography 49, n. 4 (20 luglio 2016): 1253–65. http://dx.doi.org/10.1107/s1600576716009006.
Testo completoAbstract (sommario):
Co–Re alloys are being developed for ultra-high-temperature applications to supplement Ni-based superalloys in future gas turbines. The main goal of the alloy development is to increase the maximum service temperature of the alloy beyond 1473 K,i.e.at least 100 K more than the present single-crystal Ni-based superalloy turbine blades. Co–Re alloys are strengthened by carbide phases, particularly the monocarbide of Ta. The binary TaC phase is stable at very high temperatures, much greater than the melting temperature of superalloys and Co–Re alloys. However, its stability within the Co–Re–Cr system has never been studied systematically. In this study an alloy with the composition Co–17Re–23Cr–1.2Ta–2.6C was investigated using complementary methods of small-angle neutron scattering (SANS), scanning electron microscopy, X-ray diffraction and neutron diffraction. Samples heat treated externally and samples heatedin situduring diffraction experiments exhibited stable TaC precipitates at temperatures up to 1573 K. The size and volume fraction of fine TaC precipitates (up to 100 nm) were characterized at high temperatures within situSANS measurements. Moreover, SANS was used to monitor precipitate formation during cooling from high temperatures. When the alloy is heated the matrix undergoes an allotropic phase transformation from the ∊ phase (hexagonal close-packed) to the γ phase (face-centred cubic), and the influence on the strengthening TaC precipitates was also studied within situSANS. The results show that the TaC phase is stable and at these high temperatures the precipitates coarsen but still remain. This makes the TaC precipitates attractive and the Co–Re alloys a promising candidate for high-temperature application.
32
Britto, Douglas de, e Odilio Benedito Garrido Assis. "Chemical, biochemical, and microbiological aspects of chitosan quaternary salt as active coating on sliced apples". Food Science and Technology 32, n. 3 (14 agosto 2012): 599–605. http://dx.doi.org/10.1590/s0101-20612012005000089.
Testo completoAbstract (sommario):
The biocompatibility of chitosan and chitosan quaternary salt coatings was evaluated for use as edible coatings for sliced apple. Measurement of water loss, color change, and fungal growth appearance were monitored as a function of time. A significant brownish effect was observed on chitosan coated slices, varying greatly from L* = 76.5 and Hue angle = 95.9° (t = 0) to L* = 45.3 and Hue angle = 69.8° (t = 3 days), whilst for TMC coated samples the variation was considerable lower (L* = 74.1; Hue angle = 95.0°) to (L* = 67.0; Hue angle = 83.8°) within the same period. The hydrosoluble derivative N,N,N-trimethylchitosan demonstrated good antifungal activity against P. expansum although highly dependent on the polymer properties such as degree of quaternization. The most efficient formulation was that prepared from derivative having a degree of quaternization of 45%, high solubility, and high viscosity. This formulation restrained fungus spreading up to 30%, while for the control it reached almost 80% of the total assessed surfaces during 7 days of storage.
33
Wang, Fei, Xuemin Zhang, Lei Dong, Jing Liu, Zhiqiang Mao, Kai Lin e Chieh-Hung Chen. "Monitoring Seismo-TEC Perturbations Utilizing the Beidou Geostationary Satellites". Remote Sensing 15, n. 10 (17 maggio 2023): 2608. http://dx.doi.org/10.3390/rs15102608.
Testo completoAbstract (sommario):
Electromagnetic signals transmitted from the Beidou geostationary satellites can be utilized to monitor changes in ionospheric total electron contents (TECs) at motionless ionospheric pierce points (IPPs) over the Earth’s surface 24 h a day. The TEC perturbations at close IPPs detected via distinct horizontal azimuths and elevation angles can be examined by utilizing different measuring geometries formed by the selected geostationary satellites and ground-based Global Navigation Satellite System (GNSS) stations. The M6.9 Menyuan earthquake occurred in northwest China on 7 January 2022. We collected TEC perturbations associated with the Menyuan earthquake at those motionless IPPs to examine the capability of the TEC measurements utilizing distinct horizontal azimuths and elevation angles. The experimental results show that the TEC perturbations associated with the earthquake traveled away from the area around the epicenter with velocities of ~800 m/s and ~1000 m/s in the ionosphere. The traveling TEC perturbations were consistently observed in different geometries. Such novel results show that the pronounced TEC perturbations can be obtained once the satellite hanging high over the Earth’s surface in front of the traveling TEC perturbations is selected. This study shows that geostationary satellites provide an excellent opportunity to conduct experiments on the advantage of the TEC observation technology.
34
Tong, Xiao, Hao Fu, Xu Jie He, Li Min Zhao e Tong Jiang. "Economic Evaluation Methodology of New Energy-Saving Power Transformers and Suggestions for Challenges". Applied Mechanics and Materials 668-669 (ottobre 2014): 775–79. http://dx.doi.org/10.4028/www.scientific.net/amm.668-669.775.
Testo completoAbstract (sommario):
For energy-saving and consumption-reducing, new energy-saving transformer becomes more and more important. Via an economic evaluation methodology called Total Owning Cost (TOC), this article compares energy-saving transformer with high-energy transformer for examples in the angle of transformer loss and picks up the optimum energy-efficient transformer which can be expected to gain more benefit during transformer life cycle. This article also analyses cost of silicon steel sheet used in the transformer core and benefit in Total Owning Cost (TOC) of upgrading silicon steel sheet which primarily reduces no-load loss. Based on calculated results of Total Owning Cost (TOC) and payback period, the new energy-efficient transformer replacement plan, economic discussion and promotion proposal are brought up.
35
Abdelaal, Mohamed, Mohamed Hazem Abdellatif, Moritz Riede e Ghada Bassioni. "Studying the Effect of High Substrate Temperature on the Microstructure of Vacuum Evaporated TAPC: C60 Organic Solar Thin Films". Materials 14, n. 7 (1 aprile 2021): 1733. http://dx.doi.org/10.3390/ma14071733.
Testo completoAbstract (sommario):
Organic solar cells (OSCs), also known as organic photovoltaics (OPVs), are an emerging solar cell technology composed of carbon-based, organic molecules, which convert energy from the sun into electricity. Key for their performance is the microstructure of the light-absorbing organic bulk heterojunction. To study this, organic solar films composed of both fullerene C60 as electron acceptor and different mole percentages of di-[4-(N,N-di-p-tolyl-amino)-phenyl]-cyclohexane (TAPC) as electron donor were evaporated in vacuum in different mixing ratios (5, 50 and 95 mol%) on an ITO-coated glass substrate held at room temperature and at 110 °C. The microstructure of the C60: TAPC heterojunction was studied by grazing incidence wide angle X-ray scattering to understand the effect of substrate heating. By increasing the substrate temperature from ambient to 110 °C, it was found that no significant change was observed in the crystal size for the C60: TAPC concentrations investigated in this study. In addition to the variation done in the substrate temperature, the variation of the mole percent of the donor (TAPC) was studied to conclude the effect of both the substrate temperature and the donor concentration on the microstructure of the OSC films. Bragg peaks were attributed to C60 in the pure C60 sample and in the blend with low donor mole percentage (5%), but the C60 peaks became nondiscernible when the donor mole percentage was increased to 50% and above, showing that TAPC interrupted the formation of C60 crystals.
36
Ishizuka, Kazuo. "New form of Transmission Cross Coefficient for High-Resolution Imaging". Proceedings, annual meeting, Electron Microscopy Society of America 48, n. 1 (12 agosto 1990): 60–61. http://dx.doi.org/10.1017/s0424820100179051.
Testo completoAbstract (sommario):
It is well known that taking into account spacial and temporal coherency of illumination as well as the wave aberration is important to interpret an image of a high-resolution electron microscope (HREM). This occues, because coherency of incident electrons restricts transmission of image information. Due to its large spherical and chromatic aberrations, the electron microscope requires higher coherency than the optical microscope. On an application of HREM for a strong scattering object, we have to estimate the contribution of the interference between the diffracted waves on an image formation. The contribution of each pair of diffracted waves may be properly represented by the transmission cross coefficients (TCC) between these waves. In this report, we will show an improved form of the TCC including second order derivatives, and compare it with the first order TCC.In the electron microscope the specimen is illuminated by quasi monochromatic electrons having a small range of illumination directions. Thus, the image intensity for each energy and each incident direction should be summed to give an intensity to be observed. However, this is a time consuming process, if the ranges of incident energy and/or illumination direction are large. To avoid this difficulty, we can use the TCC by assuming that a transmission function of the specimen does not depend on the incident beam direction. This is not always true, because dynamical scattering is important owing to strong interactions of electrons with the specimen. However, in the case of HREM, both the specimen thickness and the illumination angle should be small. Therefore we may neglect the dependency of the transmission function on the incident beam direction.
37
Wu, Dong L., Daniel J. Emmons e Nimalan Swarnalingam. "Global GNSS-RO Electron Density in the Lower Ionosphere". Remote Sensing 14, n. 7 (24 marzo 2022): 1577. http://dx.doi.org/10.3390/rs14071577.
Testo completoAbstract (sommario):
Lack of instrument sensitivity to low electron density (Ne) concentration makes it difficult to measure sharp Ne vertical gradients (four orders of magnitude over 30 km) in the D/E-region. A robust algorithm is developed to retrieve global D/E-region Ne from the high-rate GNSS radio occultation (RO) data, to improve spatiotemporal coverage using recent SmallSat/CubeSat constellations. The new algorithm removes F-region contributions in the RO excess phase profile by fitting a linear function to the data below the D-region. The new GNSS-RO observations reveal many interesting features in the diurnal, seasonal, solar-cycle, and magnetic-field-dependent variations in the Ne morphology. While the D/E-region Ne is a function of solar zenith angle (χ), it exhibits strong latitudinal variations for the same χ with a distribution asymmetric about noon. In addition, large longitudinal variations are observed along the same magnetic field pitch angle. The summer midlatitude Ne and sporadic E (Es) show a distribution similar to each other. The distribution of auroral electron precipitation correlates better with the pitch angle from the magnetosphere than from one at 100 km. Finally, a new TEC retrieval technique is developed for the high-rate RO data with a top reaching at least 120 km. For better characterization of the E- to F-transition in Ne and more accurate TEC retrievals, it is recommended to have all GNSS-RO acquisition routinely up to 220 km.
38
Ho, Tsung-Jung, Kuei-Ting Chou, Cheng-Hsuan Li, Bor-Chen Kuo e Tzung-Chi Huang. "Quantitative Motion Analysis of Tai Chi Chuan: The Upper Extremity Movement". BioMed Research International 2018 (2018): 1–9. http://dx.doi.org/10.1155/2018/2538765.
Testo completoAbstract (sommario):
The quantitative and reproducible analysis of the standard body movement in Tai Chi Chuan (TCC) was performed in this study. We aimed to provide a reference of the upper extremities for standardizing TCC practice. Microsoft Kinect was used to record the motion during the practice of TCC. The preparation form and eight essential forms of TCC performed by an instructor and 101 practitioners were analyzed in this study. The instructor completed an entire TCC practice cycle and performed the cycle 12 times. An entire cycle of TCC was performed by practitioners and images were recorded for statistics analysis. The performance of the instructor showed high similarity (Pearson correlation coefficient (r)=0.71~0.84) to the first practice cycle. Among the 9 forms, lay form had the highest similarity (rmean=0.90) and push form had the lowest similarity (rmean=0.52). For the practitioners, ward off form (rmean=0.51) and roll back form (rmean=0.45) had the highest similarity with moderate correlation. We used Microsoft Kinect to record the spatial coordinates of the upper extremity joints during the practice of TCC and the data to perform quantitative and qualitative analysis of the joint positions and elbow joint angle.
39
Kumar, Rajive, Prashant Bansal, Bader S. Al-Mal, Sagnik Dasgupta, Colin Sayers, Peck Hwa David Ng, Andy Walz, Andrew Hannan, Edan Gofer e Chuck Wagner. "Seismic data conditioning and orthotropic rock-physics-based inversion of wide-azimuth P-wave seismic data for fracture and total organic carbon characterization in a north Kuwait unconventional reservoir". GEOPHYSICS 83, n. 4 (1 luglio 2018): B229—B240. http://dx.doi.org/10.1190/geo2017-0673.1.
Testo completoAbstract (sommario):
Optimization of production from unconventional reservoirs requires estimates of reservoir properties such as porosity, total organic carbon (TOC) content, clay content, fluid saturation, and fracture intensity. The porosity and TOC content help to determine reservoir quality, and the natural fracture intensity provides information important for the completion strategy. Because shale reservoirs display intrinsic anisotropy due to layering and the partial alignment of clay minerals and kerogen with the bedding plane, the minimum acceptable representation of the anisotropy of naturally fractured shale-gas reservoirs is orthotropy, in which a set of vertical compliant fractures is embedded in a vertical transverse isotropic (VTI) background medium. Full-azimuth seismic data are required to characterize such reservoirs and to invert for the anisotropic elastic properties. Orthotropic inversion uses azimuthally sectored seismic data stacked according to the incident angle. Even for high-fold acquisition, this azimuth/angle grouping can result in low-fold angle stacks. Orthotropic amplitude-variation-with-offset-and-azimuth (AVOAz) inversion requires seismic preconditioning techniques that ensure proper primary amplitude preservation, noise attenuation, and data alignment, and a workflow implemented for the construction of an orthotropic rock-physics model. This model integrates well and core data to estimate reservoir properties using the results of the AVOAz inversion. The seismic inversion results include the P- and S-impedance and parameters quantifying the azimuthal anisotropy. The rock model assumes a VTI kerogen-rich layer, containing aligned vertical fractures, and it uses prestack orthotropic AVOAz inversion results to predict porosity, TOC, and fracture intensity.
40
Kuvshinova, Maria A., Sergey V. Saroyan e Anna V. Goncharova. "Improving transscleral cyclophotocoagulation for the treatment of dogs with different forms of glaucoma". Veterinariya, Zootekhniya i Biotekhnologiya 5, n. 126 (2024): 76–88. http://dx.doi.org/10.36871/vet.zoo.bio.202405008.
Testo completoAbstract (sommario):
Treatment of glaucoma in dogs with conservative methods does not always achieve a sufficient hypotensive effect, so the issue of surgical intervention is relevant. Due to the high risk of complications after invasive surgery, the use of transscleral cyclophotocoagulation (TCPC) is advisable. The article discusses the principle of selecting a protocol for laser exposure to the eye in the treatment of various forms of glaucoma in dogs. The work was carried out at the Department of Veterinary Surgery of the Federal State Budgetary Educational Institution of Higher Education MGAVMiB – MBA named after K. I. Skryabin and at the VC CEVO&M. To perform TCPC, the Endo Optiks E2 video endoscopic laser ophthalmological system was used, which contains a 175 W xenon light source, a compact diode laser with a wavelength of 810 nm, a power of 2,0 W and the ability to operate in pulsed and continuous modes, and a probe for TCPC. Depending on the form of glaucoma and the degree of increase in intraocular pressure, the total power of laser exposure to the eye varied. The results were assessed on the 1st day after surgery, on the 7th and on the 30th using a developed scoring system that takes into account the degree of reduction in intraocular pressure, changes in pupillary reflexes and clinical symptoms. The study found that in dogs with different forms of glaucoma and different initial intraocular pressure, the required hypotensive effect was achieved with different powers of the total impact of laser radiation on the eye. This protocol makes it possible to achieve a stable hypotensive effect in dogs with primary open-angle glaucoma (POAG) in 90 % of cases, in dogs with primary angle-closure glaucoma (PACG) in 66,7 % of cases, in dogs with secondary angle-closure glaucoma (SACG) in 58,82 % of cases. The study demonstrates the effectiveness of the proposed laser power protocol for the treatment of various forms of glaucoma in dogs. The best results were achieved in dogs with POAG (n=10). For dogs with angle-closure glaucoma, TCPC, as the only treatment method, does not achieve a stable hypotensive effect in the short-term and long-term period. In the case of PACG and SACG, it is necessary to use combined methods to reduce the production of intraocular fluid (TCPC) and to normalize the function of the drainage system of the eye.
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Liu, C. H., Wen-Zhi Li e Heng-De Li. "TiC/metal nacrous structures and their fracture toughness increase". Journal of Materials Research 11, n. 9 (settembre 1996): 2231–35. http://dx.doi.org/10.1557/jmr.1996.0283.
Testo completoAbstract (sommario):
Multilayers of TiC and a series of metals have been fabricated by ion beam sputtering deposition to simulate nacre. The individual layer thickness varies from 1 to 10 nm, and the total thickness of the multilayers is about 1 μm. Transmission electron microscopy (TEM), low-angle x-ray diffraction (LXRD), and high-resolution electron microscopy (HREM) show their periodicity and lattice images. A particular method is devised to evaluate the relative toughness of this artificial pearlite. It is shown that the toughness of these nanocomposite materials can be tremendously improved. A maximum of toughness appears at a certain modulation. Metals with high plasticity such as Al and Cu can produce a particularly spectacular effect on increasing the toughness of these multilayers.
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Uemura, Sojiro, Shiho Yamamoto Kamata, Kyosuke Yoshimi e Sadahiro Tsurekawa. "Microstructural evolution during high-temperature tensile creep at 1,500°C of a MoSiBTiC alloy". High Temperature Materials and Processes 39, n. 1 (29 aprile 2020): 136–45. http://dx.doi.org/10.1515/htmp-2020-0039.
Testo completoAbstract (sommario):
AbstractMicrostructural evolution in the TiC-reinforced Mo–Si–B-based alloy during tensile creep deformation at 1,500°C and 137 MPa was investigated via scanning electron microscope-backscattered electron diffraction (SEM-EBSD) observations. The creep curve of this alloy displayed no clear steady state but was dominated by the tertiary creep regime. The grain size of the Moss phase increased in the primary creep regime. However, the grain size of the Moss phase was found to remarkably decrease to <10 µm with increasing creep strain in the tertiary creep regime. The EBSD observations revealed that the refinement of the Moss phase occurred by continuous dynamic recrystallization including the transformation of low-angle grain boundaries to high-angle grain boundaries. Accordingly, the deformation of this alloy is most likely to be governed by the grain boundary sliding and the rearrangement of Moss grains such as superplasticity in the tertiary creep regime. In addition, the refinement of the Moss grains surrounding large plate-like T2 grains caused the rotation of their surfaces parallel to the loading axis and consequently the cavitation preferentially occurred at the interphases between the end of the rotated T2 grains and the Moss grains.
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Ali, Syed Abbas, e Samir Saraswati. "A comparison of sliding mode and FRF-based observers for cylinder pressure estimation of spark ignition engine". Transactions of the Institute of Measurement and Control 39, n. 2 (20 luglio 2016): 163–72. http://dx.doi.org/10.1177/0142331215604895.
Testo completoAbstract (sommario):
A sliding mode observer (SMO) is proposed for the estimation of cylinder pressure using crankshaft speed fluctuations. SMO parameters are updated using the difference between measured and observed crankshaft speed. The governing equations of cylinder pressure and crankshaft speed are described by a one-zone combustion model and crankshaft model dynamics, respectively. The observer is found to be unstable at top dead centre (TDC) due to zero combustion torque at this point. To prevent instability, observer gains are switched off near TDC and observer performance depends only on the modelling accuracies of the combustion model. This model is further improved by modelling flame development angle [Formula: see text] and rapid burning angle [Formula: see text] as a function of spark advance, equivalence ratio, mean speed and manifold pressure. Experimental investigations are carried out to test and validate the model on a spark ignition engine coupled with a dynamometer. The results of the SMO are compared with cylinder pressure profile estimated using a frequency response function (FRF). It is seen that the averaged relative error, using SMO, is reduced for all the test conditions in comparison with cylinder pressure estimation using FRF. This reduction in averaged relative error is more significant at the low-load, high-speed conditions where cycle-by-cycle variations are quite high.
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Liu, Longhai, Haiyuan Yu, Chenglong Zheng, Dongdong Ye, Wei He, Silei Wang, Jining Li et al. "Nondestructive Thickness Measurement of Thermal Barrier Coatings for Turbine Blades by Terahertz Time Domain Spectroscopy". Photonics 10, n. 2 (19 gennaio 2023): 105. http://dx.doi.org/10.3390/photonics10020105.
Testo completoAbstract (sommario):
Owing to its high penetrability with dielectric materials, terahertz time domain spectroscopy (THz-TDS) is a promising nondestructive measurement technology. The coating thickness deviation and defect of thermal barrier coatings (TBC) will affect its thermal insulation performance and lifetime. In this work, THz-TDS was applied to measure the coating thickness distribution of TBC. The refractive index was obtained by THz-TDS transmission mode. To avoid the normal incidence THz signal loss, the THz signal was reflected from the TBC with a 10° incident angle, which also made the measurement result insensitive to the unevenness and tilt of the TBC sample. In the experiment, the yttria-stabilized zirconia (YSZ) TBC was measured by THz-TDS to estimate the thickness distribution. To validate the thickness measurements, metallography was introduced to correlate the TBC thickness result. The measurement deviation was within 12.1 µm, i.e., 3.45% for the THz-TDS and metallography result. A piece of turbine blade was measured by THz-TDS and a eddy current test. The maximum deviation was 8.48 µm, i.e., 2.36% of these two methods. Unlike the eddy current test, the THz-TDS thickness result was not affected by the cooling holes. The effectiveness of the nondestructive thickness measurement of TBC for turbine blades by THz-TDS was verified.
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Dang, Huyen T., Roberto M. Narbaitz, Takeshi Matsuura e Kailash C. Khulbe. "A Comparison of Commercial and Experimental Ultrafiltration Membranes via Surface Property Analysis and Fouling Tests". Water Quality Research Journal 41, n. 1 (1 febbraio 2006): 84–93. http://dx.doi.org/10.2166/wqrj.2006.009.
Testo completoAbstract (sommario):
Abstract Surface modified polyethersulfone (PES) membranes via the addition of different hydrophiLic Surface Modifying Macromolecules (LSMMs) have been developed by Matsuura, Narbaitz and co-workers. This study compares the performance of the best PES-LSMM membrane with nine commercial ultrafiltration membranes manufactured using five different types of base polymers (polyethersulfone, polysulfone, celluloseacetate, polyacrylonitrile and cellulose) in the same range of molecular weight cutoff (MWCO) (from 40 to 120 kDal). All membranes were characterized by using atomic force microscopy, contact angle measurements, solute transport analysis and then evaluated through fouling tests with Ottawa River water (ORW). While PES-LSMM membranes had much lower initial flux than the commercial membranes, they had the highest total organic carbon (TOC) rejection (80%) and the lowest flux reduction (62%). For the commercial membranes, the range of TOC rejections and flux reductions were 62 to 80% and 68 to 80%, respectively. Given their high TOC rejection and relatively high foulant deposition, fouling of the PES-LSMM membranes appears to be controlled by a surface gel.
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Rahayu, Susi, Dian W. Kurniawidi e Abdul Gani. "Pemanfaatan Limbah Cangkang Kerang Mutiara (Pinctada Maxima) Sebagai Sumber Hidroksiapatit". Jurnal Pendidikan Fisika dan Teknologi 4, n. 2 (8 novembre 2018): 226. http://dx.doi.org/10.29303/jpft.v4i2.839.
Testo completoAbstract (sommario):
Pearl shells (pinctada maxima) are the superior commodities in West Nusa Tenggara Province. The shellfish is utilized as a producer of pearls while the waste of pearl shells has not been widely used by the community. Main composition of fhe pearl shells is calcium. CaO content was tested using AAS and obtained CaO in shells as much as 52.23%. CaO is used as a source of hydroxyapatite (HAp). Shellfish powder is synthesized with H3PO4 compound. Synthesis is conducted by precipitation method. Synthesis results were analyzed utilizing XRD and FTIR. From the examination, HAp compounds were identified. Group of PO43, CO32, and OH are constituent groups of HAp compounds. Moreover, another calcium phosphate is formed namely TCP. This HAp compound has a maximum crystallinity of 78.33% at an angle of 77.18 °. The smallest HAp particle size at an angle of 31.92 ° is 1.4 μm. The degree of high crystallinity is influenced by high intensity and a wide FWHM. Meanwhile, the small molecule size is acquired on a wide FWHM with a small Bragg angle position.
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Kakoee, Alireza, Maciej Mikulski, Aneesh Vasudev, Martin Axelsson, Jari Hyvönen, Mohammad Mahdi Salahi e Amin Mahmoudzadeh Andwari. "Start of Injection Influence on In-Cylinder Fuel Distribution, Engine Performance and Emission Characteristic in a RCCI Marine Engine". Energies 17, n. 10 (14 maggio 2024): 2370. http://dx.doi.org/10.3390/en17102370.
Testo completoAbstract (sommario):
Reactivity-controlled compression ignition (RCCI) is a promising new combustion technology for marine applications. It has offered the potential to achieve low NOx emissions and high thermal efficiency, which are both important considerations for marine engines. However, the performance of RCCI engines is sensitive to a number of factors, including the start of injection. This study used computational fluid dynamics (CFD) to investigate the effects of start of ignition (SOI) on the performance of a marine RCCI engine. The CFD model was validated against experimental data, and the results showed that the SOI has a significant impact on the combustion process. In particular, the SOI affected the distribution of fuel and air in the combustion chamber, which in turn affected the rate of heat release and the formation of pollutants. Ten different SOIs were implemented on a validated closed-loop CFD model from 96 to 42 CAD bTDC (crank angle degree before top dead center) at six-degree intervals. A chemical kinetic mechanism of 54 species and 269 reactions tuned and used for simulation of in-cylinder combustion. The results show that in early injection, high-reactivity fuel was distributed close to the liner. This distribution was around the center of late injection angles. A homogeneity study was carried out to investigate the local equivalence ratio. It showed a more homogenous mixture in early injection until 66 CAD bTDC, after which point, earlier injection timing had no effect on homogeneity. Maximum indicated mean effective pressure (IMEP) was achieved at SOI 48 CAD bTDC, and minimum amounts of THC (total hydrocarbons) and NOx were observed with middle injection timing angles around 66 CAD bTDC.
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Stelzer, Vera, e Lars Krenkel. "2D numerical investigations derived from a 3D dragonfly wing captured with a high-resolution micro-CT". Technology and Health Care 30, n. 1 (29 dicembre 2021): 283–89. http://dx.doi.org/10.3233/thc-219010.
Testo completoAbstract (sommario):
BACKGROUND: Due to their corrugated profile, dragonfly wings have special aerodynamic characteristics during flying and gliding. OBJECTIVE: The aim of this study was to create a realistic 3D model of a dragonfly wing captured with a high-resolution micro-CT. To represent geometry changes in span and chord length and their aerodynamic effects, numerical investigations are carried out at different wing positions. METHODS: The forewing of a Camacinia gigantea was captured using a micro-CT. After the wing was adapted an error-free 3D model resulted. The wing was cut every 5 mm and 2D numerical analyses were conducted in Fluent® 2020 R2 (ANSYS, Inc., Canonsburg, PA, USA). RESULTS: The highest lift coefficient, as well as the highest lift-to-drag ratio, resulted at 0 mm and an angle of attack (AOA) of 5∘. At AOAs of 10∘ or 15∘, the flow around the wing stalled and a Kármán vortex street behind the wing becomes visible. CONCLUSIONS: The velocity is higher on the upper side of the wing compared to the lower side. The pressure acts vice versa. Due to the recirculation zones that are formed in valleys of the corrugation pattern the wing resembles the form of an airfoil.
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López-Cuevas, Jorge, Juan Carlos Rendón-Angeles, J. L. Rodríguez-Galicia, M. Herrera-Trejo e J. Méndez-Nonell. "High Temperature Chemical Interaction Between SSiC Substrates and Ag-Cu Based Liquid Alloys in Vacuo". Materials Science Forum 509 (marzo 2006): 111–16. http://dx.doi.org/10.4028/www.scientific.net/msf.509.111.
Testo completoAbstract (sommario):
The interfaces formed at 850 °C under vacuum between polished or oxidized substrates of pressureless sintered α-SiC (SSiC) and Cusil, Cusil-ABA and Incusil-ABA brazing alloys have been characterized by X-ray diffraction, scanning electron microscopy and energy dispersive spectroscopy. No chemical interaction is observed for Cusil on both SSiC substrates. In contrast, the Ti contained in the Cusil-ABA and Incusil-ABA alloys promotes the occurrence of chemical reactions at the metal/ceramic interface with both SSiC substrates. The formation of TiC and Ti5Si3 is observed for Cusil-ABA and Incusil-ABA on untreated SSiC, following the sequence SiC → TiC → Ti5Si3 at the metal/ceramic interface. The formation of Ti5Si3 and Cu3Ti3O, following the sequence SiC → Ti5Si3 → Cu3Ti3O, is observed for both Ti-containing alloys on pre-oxidized SSiC. During the wetting experiments, Ti5Si3 and Cu3Ti3O detach from the ceramic surface, floating away from the ceramic/metal interface into the liquid alloy, where the latter phase partially dissolves. It is concluded that for both Ti-containing alloys in contact with pre-oxidized SSiC, the Ti remaining after the reaction with the silica film is insufficient to decrease the contact angle to the values observed for untreated SSiC or to produce a strong metal/ceramic joint.
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Elhady, Sarah, Mohamed Bassyouni, Ramadan A. Mansour, Medhat H. Elzahar, Shereen Abdel-Hamid, Yasser Elhenawy e Mamdou Y. Saleh. "Oily Wastewater Treatment Using Polyamide Thin Film Composite Membrane Technology". Membranes 10, n. 5 (28 aprile 2020): 84. http://dx.doi.org/10.3390/membranes10050084.
Testo completoAbstract (sommario):
In this study, polyamide (PA) thin film composite (TFC) reverse osmosis (RO) membrane filtration was used in edible oil wastewater emulsion treatment. The PA-TFC membrane was characterized using mechanical, thermal, chemical, and physical tests. Surface morphology and cross-sections of TFCs were characterized using SEM. The effects of edible oil concentrations, average droplets size, and contact angle on separation efficiency and flux were studied in detail. Purification performance was enhanced using activated carbon as a pre-treatment unit. The performance of the RO unit was assessed by chemical oxygen demand (COD) removal and permeate flux. Oil concentration in wastewater varied between 3000 mg/L and 6000 mg/L. Oily wastewater showed a higher contact angle (62.9°) than de-ionized water (33°). Experimental results showed that the presence of activated carbon increases the permeation COD removal from 94% to 99%. The RO membrane filtration coupled with an activated carbon unit of oily wastewater is a convenient hybrid technique for removal of high-concentration edible oil wastewater emulsion up to 99%. Using activated carbon as an adsorption pre-treatment unit improved the permeate flux from 34 L/m2hr to 75 L/m2hr.