bluuebunny/crossref_metadata_2025 huggingface dataset:
Research and Application of Key Technology of Data-Driven Intelligent Manufacturing of Electronic Components
Authors: Hu Changming , Cao Yaqi , Feng Zhanying
Published: September 2020

With the development of electronic equipment towards multi-function, high performance and miniaturization, the assembly density and complexity of electronic components become higher and higher. For the manufacturing characteristics of electronic components in many varieties, small batch and mixed production line, this paper uses intelligent manufacturing technology based on industrial big data, puts forward implementation architecture of electronic components digital workshop, explores the “perception - analysis - decisions” closed-loop mechanism of all data of manufacturing process of electronic component, sets up network security platform for industrial control system which ensures workshop operate transparently and safely. The necessity and feasibility of landing of data-driven intelligent workshop are verified by an application example of digital workshop of radar core microwave components, which effectively improves the production efficiency and workshop management level.
Process Control Improvement in Deep Drawing of Hemispherical Cups Made of GLARE Material
Authors: Blala Hamza , Lang Lihui , Li Lei , Khan Shahrukh , Alexandrov Sergei
Published: September 2020

Controlling the material flow under the blank holder in hydroforming is a delicate point that can be controlled by the blank holder force (BHF), cavity pressure (CP) and the blank holder gap (BHG). BHG is one of the effective parameters to control the material flow. A numerical and experimental approach studied the impact of the BHG on the Hydromechanical Deep Drawing (HDD) of a hemispherical cup made with 2/1 Glare sheets, including another two factors, CP and BHF. BHGs with different thickness was used in the experiments to form Glare Laminate. Simulation and experiment illustrate that an optimized value of these parameters has a good effect on the forming quality and depth of the final product. Finally, an appropriate value of the BHG is projected and the explanations of the failure modes are discussed.
Innovative Manufacturing and Application of Fiber Metal Laminate Pipe
Authors: Lang Zijian , Zhang Meng , Li Xiaoxing , Huang Xing
Published: September 2020

Fiber-reinforced metal laminate tube (FMLT) is a multi-layered ultra-hybrid material that cures at fixed pressure and temperature after alternating metal laminates and fiber composites. As with the production process similar to the second-generation GLARE fiber-reinforced metal layer, the management layer of the formed composite layer should have good impact resistance characteristics, and can also be used in the impact-resistant structure of the aircraft, the landing cushion structure of the aircraft, and the body collision Device to protect aviation materials.The composite pipe fittings are made by hydraulic forming technology, which lays a good foundation for the small-scale fine processing of the pipe. In addition, use speckle models and other virtual software simulation models (such as various related software and related formulas) to monitor data before and after hydroforming of fiber-reinforced metal layer tubes, it lays a good data foundation for the hydroforming of pipes and subsequent experiments.The development and performance testing of GLARE composite tube hydraulic forming technology is of great significance to the development of lightweight and safety in the aviation industry and the automobile industry.
Study on Ultrafine Particles Used in Drilling Fluids
Authors: Cao X C , Zhou C. Y. , Li Y. Y. , Zong W , Wang J , Chen M
Published: September 2020

In this paper, several ultrafine particles were prepared and characterized, then the performance of drilling fluids were evaluated after ultrafine particles were added in water base drilling fluids. The viscosity property of drilling fluids were increased, however, filtration reduction could not be strictly controlled. All filtration volume was difficult to control just like common ultrafine calcium carbonate unless some polymers could be used. Titanium dioxide and zinc dioxide could be used as substitutes of calcium carbonate in drilling fluids.
SPH Model for Numerical Test of Heterogeneous Rock-like Material
Authors: Sun Chaoqun , Song Erlong , Zhang Luchen , Nan Feng
Published: September 2020

Based on the Smoothed Particles Hydrodynamics (SPH) method, a heterogeneous material numerical model is developed for simulation of fracture process of heterogeneous rock-like material, such as rock. The self-developed SPH program is proposed to analyse the mechanical properties of rock-like materials. In the present program, the combined Mohr-Coulomb criterion is adopted. The deformation of rock-like material under uniaxial compression can be analysed, and the acoustic emission in rock-like material can also be clarified. The calculation results show that the SPH simulation model can be used for numerical test of heterogeneous rock-like material. The process of destruction of rock specimen is evolutionary process. Rock acoustic emission records the brittle failure process of rock-like material.
Stress monitoring of long-span steel truss during construction stage in Hangzhou International Expo Center
Authors: Lin Jindi , Wei Yongbin , Qiao Maowei
Published: September 2020

According to the requirement of building function, the large-span steel structures are constantly appearing in recent years. It is necessary to establish a set of feasible methods for health monitoring of long-span steel structures. This paper introduces the structural health monitoring of large-span steel structure in Construction Stage, including the method of Structural simulation, the wireless monitoring system of large-span steel structure, the installation method of sensors, the judgment method of structural safety and the maintenance of monitoring system. Taking Hangzhou International Expo Center as an example, all construction steps of the main large-span steel structure were simulated by the finite element analysis software. Through the structure of simulation calculation, the key members of the structure were found out, and the monitoring scheme was determined and carried out. In order to get the accurate stress data during the implementation of the monitoring scheme, this paper introduced some attentive details of sensor installation. The limitation of the key steel elements was obtained according to the related norms, and it provided the judgment for the safe of structure. After the smooth construction of the project, we could find that the stress monitoring system meted the monitoring requirement during the construction stage, and the results were an important evaluation index for the structure. The research methods used in this paper could be seen as useful reference for construction of similar projects. Stress monitoring of long-span steel struss during construction stage in Hangzhou International Expo Center.
Fabrication and Characterization of PVDF with an Additive of Nanozeolite via Electrospinning and Non-solvent Induced Phase Separation (NIPS) Process
Authors: Nofitri Da Conceicao Isya Hindun , Valadares Marcal Imelda , Aquino Ruth R.
Published: September 2020

In this study, polyvinylidene fluoride with an additive of nanozeolite (PVDF/NZ) membranes were prepared, characterized and evaluated. The concentrations of the nanozeolite incorporated into PVDF were varied from 0.25%, 0.50% and 0.75 % with N-methyl-2-pyrrolidone (NMP) as solvent and the corresponding effects of nanozeolite on the polymer matrix were investigated in terms of performance and properties. There are two methods in preparing the membranes, namely: Non-solvent Induced Phase Separation (NIPS) and electrospinning. The hydrophobicity of the membranes was characterized by contact angle, the surface morphology using Scanning Electron Microscopy (SEM), and the mechanical properties by Universal Testing Machine (UTM). The presence of organic and inorganic matter was investigated using Fourier-Transform Infrared (FTIR). The SEM images of both fabricated nanocomposite membranes showed that after the addition of nanozeolite particles into PVDF matrix has affected the surface morphology, flat-sheet resulted decreasing in porous and electrospun resulted less beads and increasing fiber diameter after adding an extra amount of nanozeolite. The chemical bond or molecular structure of flat-sheet and electrospun membranes obtained same functional groups, however the electrospun resulted a high absorption of alkanes. The contact angle of both nanocomposite fabricated membranes exhibited an increasing contact angle, yet the PVDF/0.75NZ of electrospun membrane obtained higher hydrophobic surface compared to others. The result of UTM showed that on flat-sheet, the tensile strength was obtained by pure PVDF membrane while the PVDF/0.25NZ of electrospun membrane was able to achieve an optimum tensile strength. In fact, the tensile strength via NIPS need to be improved.
Separation of V-bearing phase from the vanadium slag system utilizing supergravity
Authors: Huang Weijun , Liu Yajing , Xu Dong
Published: September 2020

The crystallization and separation behaviors of the V-spinel phase in the FeO-SiO2-V2O3-TiO2 system as the main components of vanadium slag were investigated to effectively concentrate and separate vanadium from the vanadium slag. Fine V-spinel precipitates were transformed into large lumps and strip crystals by decreasing the temperature from 1773 K to 1723 K. Ti-spinel phases began to crystallize from the molten slag by further decreasing the temperature to 1673 K. In order to adequately precipitate a single V-spinel phase with suitable grain size in the crystals from the molten slag, the temperature was chosen as 1723 K. With introduction of supergravity technology, the Ti-containing slag melt went through the filter to form the Ti-containing slag, while V-spinel crystals were intercepted by the filter to form the V-enriched slag. Consequently, with G = 700 at 1723 K for 10 minutes, the mass fraction of V2O3 was increased from 17.00 wt% before separation to 32.98 wt% in the enriched slag; the recovery ratio of V2O3 reached about 86.50%. In addition, the mass fraction of TiO2 reached about 19.41 wt% in the Ti-containing slag, which could be recycled as a titanium-bearing material in the metallurgical industry.
Dual-Energy Computed Tomography for Fat Quantification in the Liver and Bone Marrow: A Literature Review
Authors: Molwitz Isabel , Leiderer Miriam , Özden Cansu , Yamamura Jin
Published: September 2020

Background With dual-energy computed tomography (DECT) it is possible to quantify certain elements and tissues by their specific attenuation, which is dependent on the X-ray spectrum. This systematic review provides an overview of the suitability of DECT for fat quantification in clinical diagnostics compared to established methods, such as histology, magnetic resonance imaging (MRI) and single-energy computed tomography (SECT).

Method Following a systematic literature search, studies which validated DECT fat quantification by other modalities were included. The methodological heterogeneity of all included studies was processed. The study results are presented and discussed according to the target organ and specifically for each modality of comparison.

Results Heterogeneity of the study methodology was high. The DECT data was generated by sequential CT scans, fast-kVp-switching DECT, or dual-source DECT. All included studies focused on the suitability of DECT for the diagnosis of hepatic steatosis and for the determination of the bone marrow fat percentage and the influence of bone marrow fat on the measurement of bone mineral density. Fat quantification in the liver and bone marrow by DECT showed valid results compared to histology, MRI chemical shift relaxometry, magnetic resonance spectroscopy, and SECT. For determination of hepatic steatosis in contrast-enhanced CT images, DECT was clearly superior to SECT. The measurement of bone marrow fat percentage via DECT enabled the bone mineral density quantification more reliably.

Conclusion DECT is an overall valid method for fat quantification in the liver and bone marrow. In contrast to SECT, it is especially advantageous to diagnose hepatic steatosis in contrast-enhanced CT examinations. In the bone marrow DECT fat quantification allows more valid quantification of bone mineral density than conventional methods. Complementary studies concerning DECT fat quantification by split-filter DECT or dual-layer spectral CT and further studies on other organ systems should be conducted.

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Current Practice of Neurosurgical Teleconsultation in Germany
Authors: Geiger Matthias Florian , Wilhelmy Saskia , Schmidt Mathias , Firsching Raimund , Groß Dominik , Clusmann Hans
Published: September 2020

Objective As neurosurgery is a demanding specialty with services in larger medical centers only, consultation over larger distances plays an important role in health care. In times of digitalization, teleconsultation for medical images and cases plays an increasing role in neurosurgical services. However, no standards and demands have been established for its execution in the subfield of neurosurgery, so far. Therefore, as a first step, we performed a survey about the current state of teleconsultation in neurosurgery in Germany.

Methods A standardized questionnaire consisting of 20 items was used to investigate the frequency of use and the operating conditions of teleconsultation in the field of neurosurgery. The survey was performed during the annual national German Society of Neurosurgery conference in 2017. Participation in the written survey was on voluntary and anonymous basis.

Results In total, 296 individuals took part in the survey (140 specialists in neurosurgery, 77 residents). Among them, 71% were male and 121 worked at a university medical center. In total, 87.5% of all participants indicated that teleconsultation was used in their institutions (n = 113 in university medical centers and n = 76 in hospitals), and a vast majority stated to have had personal experience with it (88.6% of specialists, 85.5% of residents). The most frequent initial request for a consultation was done by phone call (80.3%). Images or data were then primarily transmitted via an electronic system (77.3%), followed by transmissions via CD or by post. The reply to a consultation was also mainly done by phone call (91.3%), followed by fax, or by e-mail. No standard protocol was followed by 78.6% of the respondents, and they stated not to know about the statutory and legal rules. However, it was stated that the protection of patient data was not endangered by using teleconsultation. The usefulness of teleconsultation and its future relevance were rated highly by the participants. The risk of misinterpretation of image data, especially without having direct access to other patient data, seemed to be a critical and unequivocal challenge.

Conclusion The results of the survey demonstrate that teleconsultation for medical images and cases is a frequently used and well-accepted tool in neurosurgical health care. However, a standardized neurosurgical procedure is still lacking and the statutory rules for this field of digital medicine are generally not known in our community. Potential misinterpretation and resulting misjudgment seem to be realistic drawbacks. Thus, we see a necessity for elaboration of guidelines for teleconsultation in neurosurgery on national and European basis.
Schwannoma and Neurofibroma, Originating from the Ulnar Nerve in Neurofibromatosis: A Case Report and Review of the Literature
Authors: Tabrizi Ali , Afshar Ahmadreza , Mohebbi Iraj , Pourjabali Masoumeh , Taleb Hassan
Published: September 2020

Schwannomas and neurofibromas are rare benign tumors originating from the peripheral nerve sheath. Tumors in neurofibromatosis are mostly neurofibromas and often appear in the soft tissue of peripheral nerves. In this report, a patient presented with two large adjacent soft tissue tumors in the right wrist and distal forearm which originated from a common nerve. A schwannoma had formed beside a neurofibroma from the ulnar nerve and induced numbness and paresthesia in the little and ring fingers. Although the patient had café au lait spots on the skin, neurofibromatosis was not suspected due to lack of symptoms. The patient was referred to the current research clinic suffering from two soft tissue masses in the wrist and ulnar nerve dysfunction. In neurofibromatosis patients, two tumors of a different nature originating from a common nerve close together have rarely been described in the literature. The patient was treated by en bloc excision of the mass while protecting the nerve fascicles. The follow-up results indicated no neurological symptoms and complete restoration of ulnar nerve function.
Bioelectronic control of chloride ions and concentration with Ag/AgCl contacts
Authors: Jia Manping , Dechiruji Harika , Selberg John , Pansodtee Pattawong , Mathews Juanita , Wu Chunxiao , Levin Michael , Teodorescu Mircea , Rolandi Marco
Published: September 2020

Translation between ionic currents and measurable electronic signals is essential for the integration of natural systems and artificial bioelectronic devices. Chloride ions (Cl−) play a pivotal role in bioelectricity, and they are involved in several brain pathologies, including epilepsy and disorders of the autistic spectra, as well as cancer and birth defects. As such, controlling [Cl−] in solution can actively influence biochemical processes and can be used in bioelectronic therapies. Here, we demonstrate a bioelectronic device that uses Ag/AgCl contacts to control [Cl−] in solution by electronic means. We do so by exploiting the potential dependence of the reversible reaction, Ag + Cl− ↔ AgCl + e−, at the contact/solution interface, which is at the basis of the well-known Ag/AgCl reference electrode. In short, a negative potential on the Ag/AgCl contact transfers Cl− from the contact to the solution with increasing [Cl−] and vice versa. With this strategy, we demonstrate precise spatiotemporal control of [Cl−] in solution that can be used to affect physiological processes that are dependent on [Cl−]. As proof-of-concept, we use [Cl−] control to influence the membrane voltage on human pluripotent stem cells.
Convergence acceleration of Monte Carlo many-body perturbation methods by direct sampling
Authors: Doran Alexander E. , Hirata So
Published: September 2020

In the Monte Carlo many-body perturbation (MC-MP) method, the conventional correlation-correction formula, which is a long sum of products of low-dimensional integrals, is first recast into a short sum of high-dimensional integrals over electron-pair and imaginary-time coordinates. These high-dimensional integrals are then evaluated by the Monte Carlo method with random coordinates generated by the Metropolis–Hasting algorithm according to a suitable distribution. The latter algorithm, while advantageous in its ability to sample nearly any distribution, introduces autocorrelation in sampled coordinates, which, in turn, increases the statistical uncertainty of the integrals and thus the computational cost. It also involves wasteful rejected moves and an initial “burn-in” step as well as displays hysteresis. Here, an algorithm is proposed that directly produces a random sequence of electron-pair coordinates for the same distribution used in the MC-MP method, which is free from autocorrelation, rejected moves, a burn-in step, or hysteresis. This direct-sampling algorithm is shown to accelerate second- and third-order Monte Carlo many-body perturbation calculations by up to 222% and 38%, respectively.
Instabilities and turbulence in a forced turbulent convex wall jet
Authors: Pandey Anshuman , Gregory James W.
Published: September 2020

The outer part of a turbulent wall jet streaming over a convex surface satisfies the centrifugal instability criterion. This gives rise to streamwise vortices that convect and grow with the wall jet. These vortices are highly unsteady, which causes the turbulence characteristics of a convex wall jet to be much stronger than that of a plane wall jet. Particle image velocimetry based investigations have been carried out in this work to understand the source of this unsteadiness. A cylinder with steady spanwise heterogeneities at the nozzle lip has been used to restrict the unsteadiness of the naturally occurring streamwise vortices such that ensemble averaging techniques can be applied. The analysis reveals that the turbulent stresses are spanwise periodic; radial and azimuthal fluctuations are highest in the upwash regions, and spanwise fluctuations are highest in the downwash regions between the counter-rotating vortices. The spanwise wavelength of the vortices increases by merging, but the merging process does not restore the spanwise uniformity of the Reynolds stresses. A Proper Orthogonal Decomposition (POD) analysis in the cross-stream plane suggests the existence of instabilities that extract energy from the mean flow to sustain these fluctuations. Secondary flows produced by steadier streamwise vortices generate inflection points in the spanwise and radial directions that trigger such secondary instabilities. POD analysis in the streamwise plane reveals the presence of a traveling wave that gives rise to the spanwise meandering of the vortices. The local Strouhal number of this traveling wave, defined using the local spanwise wavelength and jet maximum velocity, is a constant value of 1. Instability waves with similar characteristics have also been observed in other centrifugally unstable flows.
Anisotropy of the magnetocaloric effect: Example of Mn5Ge3
Authors: Maraytta N. , Voigt J. , Salazar Mejía C. , Friese K. , Skourski Y. , Perßon J. , Salman S. M. , Brückel Th.
Published: September 2020

We have investigated the field direction dependence of thermo-magnetic behavior in single crystalline Mn5Ge3. The adiabatic temperature change ΔTad in pulsed fields, the isothermal entropy change ΔSiso calculated from static magnetization measurements, and heat capacity have been determined for fields parallel and perpendicular to the easy magnetic direction [001]. The isothermal magnetization measurements yield, furthermore, the uniaxial anisotropy constants in second and fourth order, K1 and K2. We discuss how the anisotropy affects the magneto-caloric effect (MCE) and compare the results to the related compound MnFe4Si3, which features an enhanced MCE, too, but instead exhibits strong easy plane anisotropy. Our study reveals the importance of magnetic anisotropy and opens new approaches for optimizing the performance of magnetocaloric materials in applications.
Comparison of wave–structure interaction dynamics of a submerged cylindrical point absorber with three degrees of freedom using potential flow and computational fluid dynamics models
Authors: Dafnakis Panagiotis , Bhalla Amneet Pal Singh , Sirigu Sergej Antonello , Bonfanti Mauro , Bracco Giovanni , Mattiazzo Giuliana
Published: September 2020

In this paper, we compare the heave, surge, and pitch dynamics of a submerged cylindrical point absorber, simulated using potential flow and fully resolved computational fluid dynamics (CFD) models. The potential flow model is based on the time-domain Cummins equation, whereas the CFD model uses the fictitious domain Brinkman penalization technique. The submerged cylinder is tethered to the seabed using a power take-off (PTO) unit, which restrains the heave, surge, and pitch motions of the converter and absorbs energy from all three modes. It is demonstrated that the potential theory overpredicts the amplitudes of heave and surge motions, whereas it results in an insignificant pitch for a fully submerged axisymmetric converter. It also underestimates the slow drift of the buoy, which the CFD model is able to capture reliably. Furthermore, we use fully resolved CFD simulations to study the performance of a three degrees of freedom cylindrical buoy under varying PTO coefficients, mass density of the buoy, and incoming wave heights. It is demonstrated that the PTO coefficients predicted by the linear potential theory are sub-optimal for waves of moderate and high steepness. The wave absorption efficiency improves significantly when a value higher than the predicted value of the PTO damping is selected. Simulations with different mass densities of the buoy show that converters with low mass densities have an increased tension in their PTO and mooring lines. Moreover, the mass density also influences the range of resonance periods of the device. Finally, simulations with different wave heights show that at higher heights, the wave absorption efficiency of the converter decreases and a large portion of available wave power remains unabsorbed.
Multilevel Monte Carlo method for the Brownian configuration field of polymer fluids
Authors: Su Jin , Hou Cuihong , Ma Yingcang , Wang Yaowu
Published: September 2020

Stochastic Brownian dynamics is an extremely powerful way to simulate the polymer dynamics in solutions and melts. Mathematically, these models are described by stochastic differential equations. The most challenging problems are the Monte Carlo algorithm, which simulates the motion of a large number of model particles and hence requires an enormous amount of computer time. It is therefore necessary to develop an efficient numerical method in operational emergency response applications. In this paper, we give an improved multilevel Monte Carlo (improved-MLMC) method based on equilibrium control variables at each level to calculate the propagation of polymers. The improved-MLMC method can be shown to result in asymptotically optimal random errors and reduce total cost when compared to the standard Monte Carlo and MLMC methods. Finally, the effect of the Wi number (dimensionless parameter) on the total cost of the presented MLMC method is also discussed in detail.
Consequences of the close relation between Rortex and swirling strength
Authors: Kolář V. , Šístek J.
Published: September 2020

Direct consequences stem from the close relation between the recently proposed vortex vector (Rortex) and the swirling strength. It is shown that these vortex-identification methods share some relevant properties: (i) both provide the same and, practically, the largest vortex region, (ii) both allow an unlimited uniaxial stretching described by an axisymmetric strain rate, so the strain-rate magnitude inside a vortex may become much larger (without any limitation) than the vorticity magnitude, and (iii) both exhibit a discontinuous outcome, known as the so-called disappearing vortex problem.
Mindfulness and shooting performance in biathlon. A prospective study
Authors: Josefsson Torbjörn , Gustafsson Henrik , Iversen Rostad Trym , Gardner Frank L. , Ivarsson Andreas
Published: September 2020

The aim of the study was to examine the temporal relationship between facets of sport‐specific dispositional mindfulness (i e., Awareness, Refocusing, Nonjudgemental attitude) and shooting performance in actual competitions, in a population of 25 elite biathlon athletes. Findings indicated that mindfulness facets were positively associated with shooting performance, with higher levels of Awareness, Refocusing, and Awareness being related to better shooting performance in competitions. In spite of the fact that the explained variance was quite small, even a minor shooting performance enhancement may increase an athlete's chance of winning a biathlon competition.
A new approach to radiochromic film dosimetry based on non-local means
Authors: Rodríguez César , López-Fernández Alfonso , García-Pinto Diego
Published: September 2020

Radiochromic film in conjunction with flatbed scanners are frequently employed as dosimeters for advanced techniques in radiotherapy. Their strengths are as follows: light element composition, low energy dependence, near biological tissue equivalence and high spatial resolution. However, they have some weaknesses as well: non-uniformities, read out noise, and scanning artifacts. Several processing protocols have been proposed intending to correct the perturbations these weaknesses produce. The aim of this paper is to present a new processing protocol for radiochromic film dosimetry based on a non-local means denoising algorithm. Three dose distributions of open square fields and a spatial combination of these fields using different angles of incidence and monitor units have been employed to validate the protocol. The dose distributions are traceable to ionization chamber measurements. Additionally, a real dose distribution of a treatment was used to simulate scanning data with noise and scanning lateral artifact, and to study how the protocol behaves under these perturbations. The same measured raw data have been processed by means of an implementation of the multichannel protocol (multigaussian method). It has been found that the proposed protocol reduces dose uncertainty even though it uses fewer scans than the multichannel protocol.
Spatial localization and pattern formation in discrete optomechanical cavities and arrays
Authors: Ruiz-Rivas J , Patera G , Navarrete-Benlloch C , Roldán E , de Valcárcel G J
Published: September 2020

We investigate theoretically the generation of nonlinear dissipative structures in optomechanical (OM) systems containing discrete arrays of mechanical resonators. We consider both hybrid models in which the optical system is a continuous multimode field, as it would happen in an OM cavity containing an array of micro-mirrors, and also fully discrete models in which each mechanical resonator interacts with a single optical mode, making contact with Ludwig and Marquardt (2013 Phys. Rev. Lett.
101, 073603). Also, we study the connections between both types of models and continuous OM models. While all three types of models merge naturally in the limit of a large number of densely distributed mechanical resonators, we show that the spatial localization and the pattern formation found in continuous OM models can still be observed for a small number of mechanical elements, even in the presence of finite-size effects, which we discuss. This opens new venues for experimental approaches to the subject.
Nanofluid flow of Higher order Radiative Chemical reaction with effects of Melting and Viscous dissipation
Authors: Jagadha S , Gopal Degavath , Kishan N
Published: September 2020

In this paper, authors investigatenon-Darcy homogeneous chemical reactions of order ‘n’ofnanofluid is discussed.The porous medium in which vertically plate kept with constant temperature and concentration. Melting and dissipation of viscosity observed in the nanofluid flow. The influence of double dispersion and radiation is analyzed. The flow maintained with invariant of time, constant density, laminar, forced and natural convection taken into account for the problem, the physical significance extracted from mathematical statements in terms of partial derivatives along with boundary conditions. The nonlinear governing partial mathematical derivatives converted into standard ordinary differential mathematical equations with the aid of similarity variable. These equations are numerically solved by MATLAB ‘bvp4c’ iterative programming methodology to seek out results of velocity-field, temperature-field, concentration-field extensively. The effect of dimensionless parameters such as Brownianmotion, thermal dispersion, melting, radiation, thermophoresis, and dimensionless numbers such as Eckert, Lewis, Prandtl, are analyzed.The heat transfer-Nusselt number and mass transfer-Sherwood number that characterize the heat transfer rate and mass transfer rate respectively outlined.
Role of water-rock interactions in the formation of the composition of radon waters of the Zaeltsovsky field (the southern part of West Siberia)
Authors: Novikov D.A. , Dultsev F.F. , Chernykh A.V.
Published: September 2020

Results of thermodynamic calculations of the interactions of radon waters from the Zaeltsovsky field with the minerals of host rocks are presented for the first time. It was established that waters under study are supersaturated with respect to calcite and siderite, and to a smaller extent with respect to magnesite and dolomite. No saturation of radon waters with respect to primary aluminosilicate minerals (albite, anortite, microcline, ferrosilite) is observed. The points are located in the fields of stability of clayey minerals (kaolinite, Ca- and Mg-montmorillonite, Fe-sepiolite), gibbsite and leptochlorite. In the evolution of the water-rock system, they correspond to the siallite type of interaction with rocks.
Effect of Controllable Parameters on the Tribological Behavior of Ceramic Particulate Reinforced Aluminium Metal Matrix Composites: A Review
Authors: Venkatesh V.S.S , Deoghare Ashish B
Published: September 2020

The inherent properties of ceramic type of reinforcements such as high fracture toughness, high corrosive resistance, improved wear resistance make it suitable as reinforcements inMetal Matrix Composites (MMC).This review article summarizes the wear behavior of ceramic particulate reinforced Aluminium Metal Matrix Composites (Al-MMC). The influence of material factors such as type of ceramic reinforcement, size and volume fraction; mechanical parameters such as sliding velocity, sliding distance and applied load on the wear behavior of Al-MMC have been discussed. The reduction in wear rate due to formation of tribolayer between the contact surfaces has been reviewed in the current study.Literature revealed that uniform distribution of hard ceramic particles (B4C, SiC) and solid lubricants (Gr, MoS2, Boron Nitride) as hybrid reinforcements can adequately enhanced the wear behavior of mating surfaces. The study illustrates that Al-MMC exclusively hybrid MMC can be treated as preeminent material for design of brake discs, piston-cylinder arrangements which require high specific strength and wear resistance.
Design of Power Analyzer using LabVIEW
Authors: Srikanth S. , Mabhu Hussain P. , Sridhar P.
Published: September 2020

Power analyzer is a device for analysis of power quality and measurement of various electrical quantities. Various power quality issues are raised in this because of the use of various non-linear loads. This paper proposes a virtual instrument for this function. the conventional measurement systems were not adequate for this purpose because they have no accurate method for deleting harmonics and ability to store data. We can overcome these difficulties by developing a virtual instrument. This is cost-effective as well as, convenient. LabVIEW provides a software platform for developing virtual instrument by acquiring current & voltage data through national instruments MyDAQ. LabVIEW provides good visualization and easy programming interface. The inputs to the proposed system are voltage and current and the hardware system developed, allows for measurement and analysis of system parameters such as power (active, reactive, apparent and instantaneous), power factor, Total Harmonic Distortion (THD) (%) and Signal-to-noise and distortion ratio (SINAD) in decibels using voltage and current. A hardware system is developed to acquire voltage and current data and work in convention with through software developed.
Functionally gradient magnesium-based composite for temporary orthopaedic implant with improved corrosion resistance and osteogenic properties
Authors: Dubey Anshu , Jaiswal Satish , Haldar Swati , Roy Partha , Lahiri Debrupa
Published: September 2020

Magnesium (Mg) is a potential alternative for conventional orthopaedic implant materials owing to its biodegradation behavior and physical characteristics similar to natural human bone. Due to its biomimetic mechanical attributes, Mg in orthopaedic applications could reduce the risk of the ‘stress shielding effect’. However, the major limitation of Mg is its high in-vivo corrosion rate. Thermal sprayed coatings of osteoconductive ceramics like hydroxyapatite (HA) have been explored as a potential solution, albeit with limited success due to the low melting point of Mg, which restricts the ease of fabricating surface-adherent ceramic coating. The present study focuses on overcoming this limitation through a Mg-HA functionally gradient material (FGM) system, which is expected to provide a highly corrosion-resistant surface and uniform mechanical integrity throughout the structure. In addition to corrosion resistance, the FGM system has improved biocompatibility and osteoconductivity without compromising its mechanical stability. The FGM, with a compositional gradient of Mg-HA composite, consisting of Mg at the core and increasing HA towards the outer layer, has been fabricated through spark plasma sintering. Mechanical properties of the overall structure were better than those of the best individual composite. More importantly, corrosion resistance of the FGM structure was significantly improved (~154%) as compared to individual composites. In addition, alkaline phosphatase activity, osteogenic gene expression and cell viability, all pertaining to efficient osteogenic differentiation, were enhanced for FGM and 15 wt% HA reinforced composites. These observations suggest that the FGM structure is promising for temporary biodegradable orthopaedic implants.
An operational information decomposition via synergistic disclosure
Authors: Rosas Fernando E , Mediano Pedro A M , Rassouli Borzoo , Barrett Adam B
Published: September 2020

Multivariate information decompositions hold promise to yield insight into complex systems, and stand out for their ability to identify synergistic phenomena. However, the adoption of these approaches has been hindered by there being multiple possible decompositions, and no precise guidance for preferring one over the others. At the heart of this disagreement lies the absence of a clear operational interpretation of what synergistic information is. Here we fill this gap by proposing a new information decomposition based on a novel operationalisation of informational synergy, which leverages recent developments in the literature of data privacy. Our decomposition is defined for any number of information sources, and its atoms can be calculated using elementary optimisation techniques. The decomposition provides a natural coarse-graining that scales gracefully with the system’s size, and is applicable in a wide range of scenarios of practical interest.
Soluble interleukin-2 receptor in exhaled breath condensate in pulmonary sarcoidosis: a cross-sectional pilot study
Authors: Terrington Dayle L , Kim Jee Whang , Ravenhill Garth , Tang Jonathan , Piec Isabelle , Fowler Stephen J , Fraser William , Wilson Andrew M
Published: September 2020

Introduction. Sarcoidosis is a chronic granulomatous disease of unknown aetiology with a variable clinical course and prognosis. There is an urgent need to identify new and novel biomarkers to help differentiate between clinical phenotypes and guide clinical decisions with respect to commencing and monitoring treatment. Across the spectrum of respiratory disease there has been a growing interest in the role of breath-based biomarkers given their non-invasive nature and ability to repeat sampling with ease for serial monitoring. Soluble interleukin-2 receptor (sIL2R) in bronchoalveolar lavage and serum correlates with disease activity in sarcoidosis; however, no previous study has evaluated sIL2R in exhaled breath.Objectives. The main aim of this cross-sectional case-controlled pilot study was to determine the concentration of sIL2R in exhaled breath condensate (EBC) from patients with recently diagnosed sarcoidosis compared to healthy volunteers and to establish, if present, if this correlated with markers of disease activity, pulmonary function tests and serological markers used in current clinical practice.Methods. Paired serum and EBC samples were collected from twelve treatment naïve patients with histologically proven sarcoidosis diagnosed during the previous six months and compared to twelve healthy volunteers matched for age and gender.Results. Mean concentration of serum sIL2R was significantly elevated in participants with sarcoidosis compared to healthy controls (1584.3 ± 489.1 versus 874.2 ± 235.7 pg mL−1; p = 0.001). Soluble interleukin-2 receptor in EBC was detectable in only five subjects including three participants with sarcoidosis. The range of sIL2R across all five samples was 148.0–288.2 pg mL−1with the two highest concentrations observed in two participants with sarcoidosis. There was no significant difference observed in EBC sIL2R between sarcoidosis and healthy controls (p = 0.71). No apparent correlations were observed between EBC sIL2R and radiological stage, pulmonary function tests or serological markers.Conclusion. Soluble interleukin-2 receptor is detectable in EBC; however, the findings from our study do not support its role as a diagnostic marker in sarcoidosis. Further research is required to evaluate its prognostic utility.
Investigating the relationship between breath aerosol size and exhaled breath condensate (EBC) metabolomic content
Authors: Schmidt Alexander J , Borras Eva , Kenyon Nicholas J , Davis Cristina E
Published: September 2020

Exhaled breath aerosols contain valuable metabolomic content due to gas exchange with blood at the alveolar capillary interface in the lung. Passive and selective filtering of these aerosols and droplets may reduce the amount of saliva contaminants and serve as an aid to enhance targeted metabolomic content when sampled in exhaled breath condensate (EBC). It is currently unknown if breath aerosol size distribution affects the types or abundances of metabolites sampled through EBC. This pilot study uses a previously described hand-held human breath sampler device with varying notch filter geometries to redirect the trajectory of breath aerosols based on size. Ten notch filter lengths were simulated with the device to calculate the effect of filter length on the breath aerosol size distribution and the proportion of aerosols which make their way through to an EBC collection tube. From three notch filter lengths, we investigate metabolite content of various aerosol fractions. We analyzed the non-volatile fraction of breath condensate with high performance liquid chromatography-mass spectrometry for broad metabolite coverage. We hypothesize that: (1) increasing the length of the notch filter in this device will prevent larger aerosols from reaching the collection tube thus altering the breath aerosol size distribution sampled in EBC; and (2) there is not a systematic large-scale difference in EBC metabolomic content that correlates with breath aerosol size. From simulation results, particles typically larger than 10 µm were filtered out. This indicates that a longer notch filter in this device prevents larger particles from reaching the collection tube thus altering the aerosol particle size distribution. Most compounds were commonly present in all three filter lengths tested, and we did not see strong statistical evidence of systematic metabolite differences between breath aerosol size distributions.
Discovery, development and exploitation of steady-state biofilms
Authors: Greenman John , Hewett Keith , Saad Saliha
Published: September 2020

Early in vitro biofilm models go back even beyond the invention of the word ‘biofilm’. In the dental field, biofilms were simply known as dental plaque and many of the first in vitro models were termed ‘artificial mouth microcosm plaques’. The purpose of this review is to highlight important elements of research from over the years regarding in vitro biofilm models, including data from our own laboratories. This helps us to interpret the models and point the way to the future development of biofilm testing. Many hypotheses regarding biofilm phenomena, particularly ecology, metabolism and physiology of volatile sulphur compounds (VSCs) and volatile organic compound (VOC) production could potentially be supported or disproved. In this way, the methods we use for screening biologically active agents including inhibitors, biocides and antimicrobial compounds in general can be improved. Hopefully, any lessons learnt in the past may be of value for the future. In this review, we focus around the need for growth rate controlled long-term biofilms; being continuously monitored using recent technical advances in bioluminescence, selective real-time electrodes, pH electrodes and continuous on-line analysis of the gas phase (both qualitatively and quantitatively). These features allow for accurate determination of growth rate and/or metabolic rate as well as pave the way towards automated assays and fine control of metabolism; impossible to achieve according to conventional biofilm theory. We also attempt to address the questions; can biofilm systems be improved to maintain long term ‘real’ or ‘true’ steady states over weeks or months, or are we limited to quasi-steady state systems for a limited period of time.
Synthesis of carbon coated iron nitride nanoparticles by using microwave plasma technique
Authors: Wei Bo , Jin Xin , Wang Qun , Li Yongqing , Khan Waheed Q
Published: September 2020

Carbon-coated iron nitride nanoparticles were synthesized using ferrocene as the precursor material with an in-house manufactured microwave-plasma reaction system. XRD revealed that the nanoparticles contained mixed phases of iron nitride (FeN0.0589 and ε-Fe3N) and α-Fe. In the case of TEM, the powder displayed a core–shell structure with a core diameter of ∼15 nm and had a multilayer carbon structure. The particle sizes in all samples were 10–80 nm. The Raman spectra of the nanoparticles justified that the multilayer carbon coatings had an amorphous graphitic structure. The nanoparticles developed at an N2 flow rate of 10 slpm yielded a superior Ms value of 37.2 emu g−1. An increase in the N2 flow rate exhibited a significant influence on the plasma temperature and reaction time, thereby affecting the composition of the mixed phase, the shape and size of the particles, and the uniformity and thickness of the carbon coating. This study provided a simple, efficient and economical method to prepare iron nitride magnetic nanoparticles, which is expected to be widely applied in industrial mass production.
Spaces 𝐶(𝐾) with an equivalent URED norm
Authors: Avilés Antonio , Troyanski Stanimir
Published: September 2020

We prove that a Banach space of continuous functions

C
(
K
)

C(K)

has a renorming that is uniformly rotund in every direction (URED) if and only if the compact space

K
K

supports a strictly positive measure.
Gelfand transforms and boundary representations of complete Nevanlinna–Pick quotients
Authors: Clouâtre Raphaël , Timko Edward
Published: September 2020

The main objects under study are quotients of multiplier algebras of certain complete Nevanlinna–Pick spaces, examples of which include the Drury–Arveson space on the ball and the Dirichlet space on the disc. We are particularly interested in the non-commutative Choquet boundaries for these quotients. Arveson’s notion of hyperrigidity is shown to be detectable through the essential normality of some natural multiplication operators, thus extending previously known results on the Arveson–Douglas conjecture. We also highlight how the non-commutative Choquet boundaries of these quotients are intertwined with their Gelfand transforms being completely isometric. Finally, we isolate analytic and topological conditions on the so-called supports of the underlying ideals that clarify the nature of the non-commutative Choquet boundaries.