bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on the comprehensive evaluation of low carbon city based on PSR model and normalized index transformation
Authors: Liu Wei , Li Fenggang , Che Kangli , Umole Chris , Jia Zhijie , Li Qinrui
Published: October 2020

Referring the “stress-state-response” (PSR) model, the index system of low-carbon city was constructed. The Immune Evolution Chaos Weed Algorithm was used to optimize the Weber Fechner index formula and the universal Carson index formula. A low-carbon city evaluation method was established and applied to evaluate the low-carbon development level of Beijing, Tianjin, Shanghai, and Chongqing in 2015. The results showed that the evaluation results of the Weber Fechner index formula and the universal Carson index formula for the four cities were basically the same. The low-carbon development level (Weber Fechner Composite Index XI) of the four cities in 2015 was ranked as follows: Beijing (0.590), Shanghai (0.499), Tianjin (0.467), Chongqing (0.461).
Far Infrared Radiation Property of Elbaite/Alumina Composite Materials
Authors: Lu Qi , Li Bowen , Zhang Huan
Published: October 2020

Far infrared materials have been prepared by precipitation method using natural elbaite powder as raw materials, which belongs to tourmaline group. The chemical formula of elbaite is Na(Al, Li)3Al6B3Si6O27(O, OH, F)4. X-ray powder diffraction (XRD) shows that elbaite and alumina in composite material has good crystal form. In addition, XRD results indicate the formation of alumina crystallites show that alumina powder exists as nano-meter particles on the surface of elbaite powder. It can be calculated the particles diameter of Al2O3 is 47.86nm. The maximum infrared radiation rate of tourmaline/alumina composite materials is 0.89 when the ratio of alumina in elbaite powder is 20%. The infrared radiation rate has been increased by 0.03, compared with single elbaite. It shows that the infrared radiation rate of the composite materials is higher than any of a single component. Two reasons are attributed to the improve of the rate of far infrared radiation: alumina powder exists as nano-meter particles and different materials will increase the absorption peak and the vibration intensity in FTIR spectra.
Magnetic dipole source TEM all-time apparent resistivity one-dimensional forward modeling and optimization calculation
Authors: Sun Zhongyuan , Meng Qingxin
Published: October 2020

Carrying out the forward modeling and one-dimensional apparent resistivity optimization calculation of TEM(transient electromagnetic method), theoretically verifies the the possibility that obtains the apparent resistivity in the full time domain under the condition of multiple offsets. By calculating the second derivative, Halley’s method can accelerate the iteration and make the function converge. The moment, offset and apparent resistivity are controlled by variable method. Halley’s method is used to iterate the moment, offset and apparent resistivity for completing the optimization calculation. In this paper, a conclusion will be finally drawn that the multi-offset TEM can get the apparent resistivity in the full time domain.
Light, water and physics in Monet painting
Authors: Coullet Pierre , Pomeau Yves
Published: October 2020

A common observation is the one of reflection of the Sun or the Moon by the slightly perturbed surface of water. In ”Impression, soleil levant”, now in Marmottant museum in Paris, Monet painted the luminous stripe resulting of this reflection when the source is low on the horizon. As we explain this stripe originates from the fluctuations of the angle of the reflecting surface when they are big enough to spread the multiple images to make them overlap, which requires that the fluctuations of the surface angle are of the same order as the angle of the Sun (or Moon) above the horizon. At higher angle the stripe become a set of non overlapping points representing each the reflected image of the source. This makes an interesting percolation transition by a continuous change of a parameter.
Microsurgery: A 10-Year Experience with Loupe Magnification
Authors: Nangole Ferdinand Wanjala , Khainga Stanley Ominde
Published: October 2020

Background Microsurgical procedures are still rare in many countries especially in resource-constrained countries. Among reasons for this is the unavailability of operating microscopes that are costly. Operating loupes are considered inferior to the microscope and are most discouraged for many microsurgical procedures. We audit patients operated under loupes for the past 10 years and present our findings.

Patients and Methods This was a prospective audit of patients who underwent microsurgical reconstructive procedures in the plastic surgery unit at Kenyatta National Hospital between January 2009 and December 2019.

Results A total of 352 patients with 360 procedures were done over a 10-year period. The age range for the patients was 5 to 90 years. Free flaps accounted for 78% of the surgical procedures (n = 298) followed by nerve repairs 8.8% (n = 32) and reimplantation surgeries 8.5% (n = 30). The overall success rate for free flaps was 93.3% with reimplantations of 77%.

Conclusion Microsurgical reconstructive procedures as demonstrated in this study can safely be done with loupes. Loupes provide an alternative means of magnification that is cost effective and cheaper. In good hands, good surgical outcomes can be achieved that are comparable to the operating microscopes.
How and Why to Define Unexplained Infertility?
Authors: Abdallah Karim S. , Hunt Sarah , Abdullah Sayed A. , Mol Ben W.J. , Youssef Mohamed A.
Published: October 2020

Unexplained infertility represents up to 30% of all cases of infertility. It is a diagnosis of exclusion, where no cause for infertility may be identified in the investigation of the couple, be it anovulation, fallopian tube blockage, or severe male factor. Unexplained infertility therefore cannot be considered a diagnosis to which a specific treatment is directed, rather that it indicates a failure to reach a diagnosis of the true cause of infertility. In this review, we explore the evidence base and potential limitations of the current routine infertility assessment. We also aim to highlight the importance of considering the prognosis of each individual couple through the process of assessment and propose a reconsidered approach to treatment, targeted to the prognosis rather than the diagnosis. Ultimately, a better understanding of the mechanisms of infertility will reduce the number of couples diagnosed with “unexplained” infertility.
Lost for words: an extraordinary structure at the early Neolithic settlement of WF16
Authors: Mithen Steven
Published: October 2020

Extraordinariness is a useful concept for everyday life and for academic research, frequently invoked within archaeology. In this contribution I explore how this term might be defined and whether it is appropriate for a large early Neolithic structure excavated at the site of WF16 in the southern Levant, dating to c. 11,200 BP. I draw on research regarding categorisation, concepts and their relationships to words, to suggest that Structure O75 can usefully be considered as ‘extraordinary’ because it does not comfortably fit into a category of finds currently used by Neolithic archaeologists. To do so, a brief review of the history of Neolithic research is required because that has shaped the categories that archaeologists bring to the archaeological record and hence what might be viewed as either ordinary or extraordinary discoveries. I conclude that extraordinary objects such as Structure O75 are likely to have played an active role in the conceptual and linguistic developments that was associated with the transition from mobile hunting and gathering to sedentary farming communities.
Generation and simple characterization of flat, liquid jets
Authors: Menzi Samuel , Knopp Gregor , Al Haddad Andre , Augustin Sven , Borca Camelia , Gashi Dardan , Huthwelker Thomas , James Daniel , Jin Jiaye , Pamfilidis Georgios , Schnorr Kirsten , Sun Zhibin , Wetter Reto , Zhang Qiang , Cirelli Claudio
Published: October 2020

We present an approach to determine the absolute thickness profile of flat liquid jets, which takes advantage of the information of thin film interference combined with light absorption, both captured in a single microscopic image. The feasibility of the proposed method is demonstrated on our compact experimental setup used to generate micrometer thin, free-flowing liquid jet sheets upon collision of two identical laminar cylindrical jets. Stable operation was achieved over several hours of the flat jet in vacuum (10−4 mbar), making the system ideally suitable for soft x-ray photon spectroscopy of liquid solutions. We characterize the flat jet size and thickness generated with two solvents, water and ethanol, employing different flow rates and nozzles of variable sizes. Our results show that a gradient of thickness ranging from a minimal thickness of 2 µm to over 10 µm can be found within the jet surface area. This enables the tunability of the sample thickness in situ, allowing the optimization of the transmitted photon flux for the chosen photon energy and sample. We demonstrate the feasibility of x-ray absorption spectroscopy experiments in transmission mode by measuring at the oxygen K-edge of ethanol. Our characterization method and the description of the experimental setup and its reported performance are expected to expand the range of applications and facilitate the use of flat liquid jets for spectroscopy experiments.
Optimization of printed sensors to monitor sodium, ammonium, and lactate in sweat
Authors: Zamarayeva Alla M. , Yamamoto Natasha A. D. , Toor Anju , Payne Margaret E. , Woods Caleb , Pister Veronika I. , Khan Yasser , Evans James W. , Arias Ana Claudia
Published: October 2020

We describe the optimization of a flexible printed electrochemical sensing platform to monitor sodium ion (Na+), ammonium ion (NH4+), and lactate in human sweat. We used previously reported material systems and adapted them to scalable fabrication techniques. In the case of potentiometric Na+ and NH4+ sensors, ion-selective electrodes (ISEs) required minimum optimization beyond previously reported protocols, while a reference electrode had to be modified in order to achieve a stable response. We incorporated a carbon nanotube (CNT) layer between the membrane and the silver/silver chloride (Ag/AgCl) layer to act as a surface for adsorption and retention of Cl−. The resulting reference electrode showed minimal potential variation up to 0.08 mV in the solutions with Cl concentration varying from 0.1 mM to 100 mM. Increasing the ionophore content in the NH4+ ISE sensing membrane eliminated an offset in the potential readout, while incorporating CNTs into the sensing membranes had a marginal effect on the sensitivity of both Na+ and NH4+ sensors. Na+ and NH4+ sensors showed a stable near-Nernstian response with sensitivities of 60.0 ± 4.0 mV and 56.2 ± 2.3 mV, respectively, long-term stability for at least 60 min of continuous operation, and selectivity to Na+ and NH4+. For the lactate sensor, we compared the performance of the tetrathiafulvalene mediated lactate oxidase based working electrode with and without diffusion-limiting polyvinyl chloride membrane. The working electrodes with and without the membrane showed sensitivities of 3.28 ± 8 A/mM and 0.43 ± 0.11 μA/mM with a linear range up to 20 mM and 30 mM lactate, respectively.
Enhanced photoelectrochemical performance in BiFeO3/g-C3N4 p–n heterojunction photocathodes with ferroelectric polarization
Authors: Wang Shun , Nan Feng , Zhou Yang , Zheng Fengang , Weng Yuyan , You Lu , Fang Liang
Published: October 2020

Ferroelectric has been considered as a promising material in the photoelectrochemical (PEC) water splitting area. Here, we design the hybrid ferroelectric–semiconductor heterostructure photocathode for enhanced PEC performance; BiFeO3 (BFO) is used for ferroelectric while two dimensional material g-C3N4 for the semiconductor. The optimized BFO/g-C3N4 heterojunction photocathode shows a 2.4 times enhancement in the photocurrent density than the pristine BFO sample. The improvement in the PEC performance is ascribed to the type II heterojunction formed between BFO and g-C3N4, resulting in the enhanced separation of the photogenerated charge carriers. More importantly, the PEC performance can be further improved by positive polarization of the BFO/g-C3N4 heterojunction photocathode. Our ferroelectric–semiconductor heterojunction material may be a promising solution for achieving highly efficient PEC systems.
Impact of UV-induced ozone and low-energy Ar+-ion cleaning on the chemical structure of Cu(In,Ga)(S,Se)2 absorber surfaces
Authors: van Maris Victor R. , Hauschild Dirk , Niesen Thomas P. , Eraerds Patrick , Dalibor Thomas , Palm Jörg , Blum Monika , Yang Wanli , Heske Clemens , Weinhardt Lothar
Published: October 2020

Dry buffer layer deposition techniques for chalcopyrite (CIGSSe)-based thin-film solar cells lack the surface-cleaning characteristics of the commonly used CdS or Zn(O,S) wet-chemical bath deposition. A UV-induced ozone and/or a low-energy Ar+-ion treatment could provide dry CIGSSe surface cleaning steps. To study the impact of these treatments, the chemical surface structure of a CIGSSe absorber is investigated. For this purpose, a set of surface-sensitive spectroscopic methods, i.e., laboratory-based x-ray photoelectron spectroscopy and x-ray-excited Auger electron spectroscopy, is combined with synchrotron-based soft x-ray emission spectroscopy. After treatment times as short as 15 s, the UV-induced ozone treatment decreases the amount of carbon adsorbates at the CIGSSe surface significantly, while the oxygen content increases. This is accompanied by the oxidation of all absorber surface elements, i.e., indium, selenium, sulfur, and copper. Short (60 s) low-energy Ar+-ion treatments, in contrast, primarily remove oxygen from the surface. Longer treatment times also lead to a removal of carbon, while extremely long treatment times can also lead to additional (likely metallic) Cu phases at the absorber surface as well.
A memory window expression to evaluate the endurance of ferroelectric FETs
Authors: Zagni Nicolò , Pavan Paolo , Alam Muhammad A.
Published: October 2020

The recent discovery of ferroelectricity in HfO2 has revived the interest into non-volatile memories based on ferroelectric transistors (FeFETs). The key advantages of these FeFETs include the low power consumption and the compatibility with the existing CMOS process. On the other hand, issues related mainly to endurance still represent a challenge to the development of the technology. In this Letter, we propose to exploit an analytical expression for the Memory Window (MW) as a simple yet effective characterization tool to evaluate the endurance of FeFETs. The MW is defined as the difference between threshold voltages occurring due to polarization switching. The analytical formulation of the MW allows one to quickly estimate the generated trap concentration as a function of number of writing cycles (or time) without recurring to numerical simulations. With the aid of the analytical model, we find that for typical program/erase pulse amplitudes and duration, endurance has a weak dependence on writing conditions. The characterization technique based on the MW would allow the systematic comparison of the performance and endurance of next-generation FeFETs.
Probing the high-pressure viscosity of hydrocarbon mixtures using molecular dynamics simulations
Authors: Kondratyuk Nikolay D. , Pisarev Vasily V. , Ewen James P.
Published: October 2020

Computational predictions of the high-pressure viscosity of hydrocarbon mixtures could help to accelerate the development of fuels and lubricants with improved performance. In this study, we use molecular dynamics simulations to study the viscosity and density of methylcyclohexane, 1-methylnaphthalene, and their binary mixtures at 323 K and pressures of up to 500 MPa. The simulation results are in excellent agreement with previous experiments available up to 100 MPa for both pure compounds (200 MPa for 1-methylnaphthalene) and the binary mixtures. For 1-methylnaphthalene, the viscosity initially increases slower-than-exponential with pressure before it reaches an inflection point and then increases faster-than-exponential. The inflection point (300 MPa) occurs at a pressure slightly below the one at which 1-methylnaphthalene is expected to enter the supercooled phase (400 MPa). For methylcyclohexane, the increase in viscosity with pressure is slower-than-exponential over the entire pressure range studied. The binary mixtures show intermediate pressure–viscosity responses between the two pure cases. The applicability of equations commonly used to describe the pressure dependence of viscosity, as well as the viscosity of binary mixtures, is evaluated against the computational predictions.
Shifting baselines and political expediency in New Zealand
Authors: Joy M. K. , Canning A. D.
Published: October 2020

The New Zealand government has been praised for heeding scientific advice in response to the COVID-19 pandemic, but when it comes to environmental protections the scientific advice seems to be negotiable. Freshwaters have been in decline for decades, despite clear science on limits needed to protect them. There are many examples of ‘shifting baselines’, where limits have been progressively weakened through agency regulatory capture and political expediency.
Collective cancer cell invasion requires RNA accumulation at the invasive front
Authors: Chrisafis George , Wang Tianhong , Moissoglu Konstadinos , Gasparski Alexander N. , Ng Yeap , Weigert Roberto , Lockett Stephen J. , Mili Stavroula
Published: October 2020

Significance

Specific RNAs are enriched at protrusive regions of migrating cells. This localization is important for cell migration on 2D surfaces. However, in vivo, tumor cells navigate complex 3D environments often in collective groups. Here, we investigated protrusion-enriched RNAs during collective 3D invasion. We show that specific RNAs exhibit a striking accumulation at the front of invasive leader cells. We provide insights into the mechanism underlying RNA accumulation at the invasive front, and we further demonstrate that it is required for efficient 3D invasion of tumor cells. We additionally observe RNA enrichment at invasive sites of in vivo tumors, supporting the physiological relevance of this mechanism and suggesting a targeting opportunity for perturbing cancer cell invasion.
Gender differences in COVID-19 attitudes and behavior: Panel evidence from eight countries
Authors: Galasso Vincenzo , Pons Vincent , Profeta Paola , Becher Michael , Brouard Sylvain , Foucault Martial
Published: October 2020

Significance

Public health response to COVID-19 requires behavior changes—isolation at home, wearing masks. Its effectiveness depends on generalized compliance. Original data from two waves of a survey conducted in March−April 2020 in eight Organisation for Economic Co-operation and Development countries (
n
= 21,649) show large gender differences in COVID-19−related beliefs and behaviors. Women are more likely to perceive the pandemic as a very serious health problem and to agree and comply with restraining measures. These differences are only partially mitigated for individuals cohabiting or directly exposed to COVID-19. This behavioral factor contributes to substantial gender differences in mortality and is consistent with women-led countries responding more effectively to the pandemic. It calls for gender-based public health policies and communication.
Typography and disciplinary identity in academic writing
Authors: Ravelli Louise J. , Starfield Sue
Published: October 2020

This paper examines the potential significance of typographic variation in the front pages of a corpus of Humanities and Social Sciences doctoral theses. Some account is taken of the linguistic content of these pages, but the primary focus is on typographic resources such as font choice, salience, and layout. It is found that there is a strong association between the nature of the typographic choices and the disciplinary orientation. Specifically, the more marked semiotic resources are likely to be associated with theses which are oriented towards the “New Humanities”, that is, adopting a more subjective approach to research.
Abundant Traveling Wave Structures of (1+1)-Dimensional Sawada-Kotera Equation: Few Cycle Solitons and Soliton Molecules*
Authors: Wang Wei , Yao Ruoxia , Lou Senyue
Published: October 2020

Traveling wave solutions have been well studied for various nonlinear systems. However, for high order nonlinear physical models, there still exist various open problems. Here, travelling wave solutions to the well-known fifth-order nonlinear physical model, the Sawada–Kotera equation, are revisited. Abundant travelling wave structures including soliton molecules, soliton lattice, kink-antikink molecules, peak-plateau soliton molecules, few-cycle-pulse solitons, double-peaked and triple-peaked solitons are unearthed.
Molecular Dynamics Simulations of the Interface between Porous and Fused Silica
Authors: Tian Ye , Yuan Xiaodong , Hu Dongxia , Zheng Wanguo , Han Wei
Published: October 2020

Molecular dynamics simulations are performed to gain insights into the structural and vibrational properties of interface between porous and fused silica. The Si–O bonds formed in the interface exhibit the same lengths as the bulk material, whereas the coordination defects in the interface are at an intermediate level as compared with the dense and porous structures. Clustered bonds are identified from the interface, which are associated with the reorganization of the silica surface. The bond angle distributions show that the O–Si–O bond angles keep the average value of 109°, whereas the Si–O–Si angles of the interface present in a similar manner to those in porous silica. Despite the slight structural differences, similarities in the vibrations are observed, which could further demonstrate the stability of porous silica films coated on the fused silica.
Fe2Ga2S5 as a 2D Antiferromagnetic Semiconductor*
Authors: Liao Chunyan , Jin Yahui , Zhang Wei , Zhu Ziming , Chen Mingxing
Published: October 2020

We theoretically investigate physical properties of two-dimensional (2D) Fe2Ga2S5 by employing first-principles calculations. It is found that it is an antiferromagnet with zigzag magnetic configuration orienting in the in-plane direction, with Néel temperatures around 160 K. The band structure of the ground state shows that it is a semiconductor with the indirect band gap of about 0.9 eV, which could be effectively tuned by the lattice strain. We predict that the carrier transport is highly anisotropic, with the electron mobility up to the order of ∼103 cm2/(V⋅s) much higher than the hole. These fantastic electronic properties make 2D Fe2Ga2S5 a promising candidate for the future spintronics.
Qualitative study of a model with Rastall gravity
Authors: Llibre Jaume , Pantazi Chara
Published: October 2020

We consider the Rastall theory for the flat Friedmann–Robertson–Walker Universe filled with a perfect fluid that satisfies a linear equation of state. The corresponding dynamical system is a two dimensional system of polynomial differential equations depending on four parameters. We show that this differential system is always Darboux integrable. In order to study the global dynamics of this family of differential systems we classify all their non-topological equivalent phase portraits in the Poincaré disc and we obtain 16 different dynamical situations for our spacetime.
Skew-symmetric endomorphisms in

M1,3

: a unified canonical form with applications to conformal geometry
Authors: Mars Marc , Peón-Nieto Carlos
Published: October 2020

We derive a canonical form for skew-symmetric endomorphisms F in Lorentzian vector spaces of dimension three and four which covers all non-trivial cases at once. We analyze its invariance group, as well as the connection of this canonical form with duality rotations of two-forms. After reviewing the relation between these endomorphisms and the algebra of conformal Killing vectors of

S

2

,

C
K
i
l
l

S

2

, we are able to also give a canonical form for an arbitrary element

ξ
∈
C
K
i
l
l

S

2

along with its invariance group. The construction allows us to obtain explicitly the change of basis that transforms any given F into its canonical form. For any non-trivial ξ we construct, via its canonical form, adapted coordinates that allow us to study its properties in depth. Two applications are worked out: we determine explicitly for which metrics, among a natural class of spaces of constant curvature, a given ξ is a Killing vector and solve all local traceless and transverse tensors that satisfy the Killing initial data equation for ξ. In addition to their own interest, the present results will be a basic ingredient for a subsequent generalization to arbitrary dimensions.
Numerical simulation of elasto-inertial focusing of particles in straight microchannels
Authors: Jiang Di , Ni Chen , Tang Wenlai , Xiang Nan
Published: October 2020

Viscoelastic microfluidics has become a new trend for particle/cell manipulation in recent years. The coupling of fluid viscoelasticity and inertia has been proved to be effective for achieving particle elasto-inertial focusing at the channel centerline experimentally, which is important for downstream particle counting and detection. However, the mechanism of particle elasto-inertial focusing in viscoelastic flow is still unclear. This paper systematically explores particle elasto-inertial focusing in straight microchannels through using numerical simulation. The performance of particle focusing is studied under various control parameters. Numerical simulation is conducted under different Reynolds numbers Re, Weissenberg numbers Wi and particle diameters d to elucidate the force competition mechanisms. The results show that the increase of flow intensity and particle diameter d can speed up the focusing migration. Elasticity of the flow quantified by Wi can attenuate the particle rotation and thus weaken the lateral particle focusing towards the channel centerline. The separatrix for particle focusing towards the channel centerline or the channel walls is observed in the simulation. The results provide new insight into understanding particle elasto-inertial focusing in viscoelastic flows, and can be useful for guiding the design of viscoelastic microfluidics.
Modeling study of the indirect treatment of phosphate buffered saline in surface air plasma
Authors: Luo Santu , Liu Zhichao , Liu Dingxin , Zhang Hao , Guo Li , Rong Mingzhe , Kong Michael G
Published: October 2020

Phosphate buffered saline (PBS) is a commonly used medium for in vitro experiments in plasma biomedicine; however, the mechanism for changes in PBS in response to plasma treatment is not well understood. Many kinds of reactive species are produced in plasma-activated PBS, but to date only a few of them can be quantified. In this paper, therefore, we aim to develop a fully coupled model for the interaction between surface air plasma and PBS, primarily to quantify its plasma-induced aqueous reactive species, as well as to elucidate their production mechanism. This model consists of a 0D sub-model for the surface plasma in air, and two 1D sub-models: for the PBS, and for the air gap between the plasma and the PBS. Similar models have been reported by our group fwith respect to the plasma treatment of deionized water. Here, by comparison, an additional 24 chlorine compounds, 17 phosphorous species and 123 chemical reactions are incorporated in our model. Our results indicate that the main aqueous reactive species are H2O2aq, O3aq, NO2aq
−, NO3aq
−, HClOaq, ClO2aq and ClO3aq
−. During plasma treatment, the oxidation reduction potential of most reactive species increases within the first 50 s, then remains almost constant. The chemical profile of the plasma-activated PBS is also plotted, from which it can be observed that some reactive oxygen species, such as OHaq, H2O2aq, and O3aq play a crucial role in the production of chlorine compounds such as HClOaq and ClO3aq
−.
Defect identification and statistics toolbox: automated defect analysis for scanning probe microscopy images
Authors: Gudinas Alana , Moscatello Jason , Hollen Shawna M
Published: October 2020

Identifying and classifying defects in scanning probe microscopy (SPM) images is an important task that is tedious to perform by hand. In this paper we present the defect identification and statistics toolbox (DIST), an image processing toolbox for identifying and analyzing atomic defects in SPM images. DIST combines automation with user input to accurately and efficiently identify defects and automatically compute critical statistics. We describe using DIST for interactive image processing, generating contour plots for isolating extrema from an image background, and processes for identifying defects.
ECT Attention Reverse Mapping algorithm: visualization of flow pattern heatmap based on convolutional neural network and its impact on ECT image reconstruction
Authors: Xu Zhuoqun , Wu Fan , Yang Yiyuan , Li Yi
Published: October 2020

The flow pattern is one of the most basic characteristic parameters of oil–gas two-phase flow, and it has a great influence on the accurate measurement of other parameters of two-phase flow. Over the past decade, the convolutional neural network (CNN) algorithm has been widely used in flow pattern research. Unfortunately, the flow pattern research based on the CNN algorithm is more on model structure optimization, and there is still little insight into the relationship between the CNN algorithm and the physical meaning of the flow pattern. Thus, in this paper, inspired by the neural network visualization gradient-based class activation mapping (Grad-CAM) method, we propose the electrical capacitance tomography (ECT) Attention Reverse Mapping algorithm (EARM) to explore the relationship between the physical meaning of flow patterns and the CNN algorithm. Specifically, the Grad-CAM method is used to obtain heatmaps of flow patterns, and the EARM algorithm combines the hotspot information of the flow pattern heatmap with the ECT image reconstruction principle, which deeply explores the relationship between the CNN flow pattern identification and the ECT image reconstruction algorithm. Furthermore, we conduct prediction experiments based on the parameters of the flow pattern hotspot capacitance data, and the experimental results are compared with the ECT original capacitance data parameter prediction. The prediction accuracy of oil–gas two-phase flow parameters has been improved by more than 50% on average, and experiments have verified the correctness of the visualization of CNN network flow pattern identification.
Nanoparticles of chosen noble metals as reactive oxygen species scavengers
Authors: Ivanova Polina , Dzięgielewski Konrad , Drozd Marcin , Skorupska Sandra , Grabowska-Jadach Ilona , Pietrzak Mariusz
Published: October 2020

Reactive oxygen species (ROS) play an important role in various physiological processes of living organisms. However, their increased concentration is usually considered as a threat for our health. Plants, invertebrates, and vertebrates including humans have various enzymatic and non-enzymatic defence systems against ROS. Unfortunately, both bad condition of surrounding environment and unhealthy lifestyle can interfere with an activity of enzymes responsible for a regulation of ROS levels. Therefore, it is important to look for alternative ROS scavengers, which could be administrated to chosen tissues to prevent pathological processes such as distortion of DNA or RNA structures and oxidation of proteins and lipids. One of the most recently proposed solutions is the application of nanozymes, which could mimic the activity of essential enzymes and prevent excessive activity of ROS. In this work, nanoparticles of Au, Pt, Pd, Ru and Rh were synthesized and studied in this regard. Peroxidase-, catalase (CAT)- and superoxide dismutase (SOD)-like activity of obtained nanoparticles were tested and compared using different methods. The influence of bovine and human albumins on CAT- and peroxidase-like activity was examined. Moreover, in the case of CAT-like activity, an influence of pH and temperature was examined and compared. Determination of SOD-like activity using the methods described for the examination of the activity of native enzyme was not fully successful. Moreover, cytotoxicity of chosen nanoparticles was studied on both regular and tumor cells.
Enhanced stability of silver nanowire transparent conductive films against ultraviolet light illumination
Authors: Wang Wenwen , Yang Zhonglin , Gu Yujia , Wu Zelei , Wang Guixin , Chen Guinan , Huang Minchu , Xu Chenhui , Ye Cui , Zhang Wang , Nai Jianwei , Peng Yongwu , Pan Jun , Ye Changhui
Published: October 2020

Silver nanowires are susceptible to degradation under ultraviolet (UV) light illumination. Encapsulating silver nanowire transparent conductive films (AgNW TCFs) with UV shielding materials usually result in the increasing of the sheet resistance or the decrease of the visible light transparency. Herein, we combine a reducing species (FeSO4) and a thin layer (overcoating) of UV shielding material to solve the stability and the optical performance issues simultaneously. The AgNW TCFs show excellent stability under continuous UV light illumination for 14 h, and their sheet resistance varies only 6%. The dramatic enhancement of the stability against UV light illumination for as-obtained TCFs will make them viable for real-world applications in touch panels and displays.
Ultrasound-induced and MRI-monitored CuO nanoparticles release from micelle encapsulation
Authors: Aresteanu Roana N Schiopu , Borodetsky Alexander , Azhari Haim , Weitz Iris S
Published: October 2020

Copper oxide nanoparticles (CuO NPs) have anticancer and antimicrobial activities. Moreover, they have a contrast enhancing effect in both MRI and ultrasound. Nonetheless, encapsulation is needed to control their toxic side effects and a mechanism for release on demand is required. A methodology is introduced herein for encapsulating and releasing CuO NPs from micelles by ultrasound induced hyperthermia and monitoring the process by MRI. For this aim, CuO NPs loaded poly(ethylene glycol)-block-poly(D,L-lactic acid) (PEG-b-PLA) micelles were prepared. Then, the profile of copper release with application of ultrasound was examined as a function of time and temperature using a colorimetric method. Finally, T1 weighted MRI images of suspensions and ex vivo poultry liver samples containing the CuO NPs loaded micelles were acquired before and after ultrasound application. The results confirmed that: (i) encapsulated NPs are detectible by MRI T1 mapping, depicting substantial T1 shortening from 1872 ± 62 ms to 683 ± 20 ms. (ii) Ultrasonic hyperthermia stimulated the NPs release with an about threefold increase compared to non-treated samples. (iii) Releasing effect was clearly visible by T1-weighted imaging (mean signal increase ratio of 2.29). These findings can potentially lead to the development of a new noninvasive methodology for CuO NPs based theranostic process.
On the biocompatibility of graphene oxide towards vascular smooth muscle cells
Authors: Ren Jianzhen , Braileanu George , Gorgojo Patricia , Valles Cristina , Dickinson Adam , Vijayaraghavan Aravind , Wang Tao
Published: October 2020

Graphene and its derivatives have shown fascinating potential in biomedical applications. However, the biocompatibility of graphene with vascular smooth muscle cells (VSMCs) and applications to vascular engineering have not been explored extensively. Using a rat aortic smooth muscle cell line, A7r5, as a VSMC model, we have explored the effects of graphene oxide (GO) on the growth and behaviours of VSMCs. Results demonstrated that GO had no obvious toxicity to VSMCs. Cells cultured on GO retained the expression of smooth muscle cell-specific markers CNN1, ACTA2 and SMTN, on both mRNA and protein levels. A wound healing assay demonstrated no effect of GO on cell migration. We also found that small-flaked GO favoured the proliferation of VSMCs, suggesting a potential of using surface chemistry or physical properties of GO to influence cell growth behaviour. These results provide insight into the suitability of GO as a scaffold for vascular tissue engineering.
Applications of AlGaN/GaN high electron mobility transistor-based sensors in water quality monitoring
Authors: Guo Hui , Jia Xiuling , Dong Yan , Ye Jiandong , Chen Dunjun , Zhang Rong , Zheng Youdou
Published: October 2020

AlGaN/GaN high electron mobility transistors (HEMTs) have demonstrated their extraordinary potential in developing solid-state microsensors for detecting gases, metal ions, anions, biomolecules, and other substances due to their excellent chemical stability, high surface charge sensitivity, high temperature-tolerance performance, and low power consumption characteristics. In this paper, only three types of AlGaN/GaN HEMT-based sensors used for detecting thepH value, heavy metal ions, and harmful anions, which are suitable for water quality monitoring, will be discussed. First, we introduce the structural design, detection principle, and fabrication processes of AlGaN/GaN HEMT-based sensors. Then, surface functionalization methods for the gate region, sensing mechanisms, and the sensitivity and selectivity performances based on different gate region treatments are reviewed and analyzed. Finally, some challenging problems that hinder the practical application of the sensors are proposed.
Inelasticity resulting from rapidity spectra analysis
Authors: Rybczyński Maciej , Włodarczyk Zbigniew
Published: October 2020

In this work we study the pseudorapidity spectra of charged particles produced in proton + proton and proton + antiproton interactions in a wide energy range using the non-extensive Tsallis approach. We evaluate the inelasticity coefficients of the discussed reactions which remain approximately independent of the collision energy.
Investigations on biogas fuelled Homogeneous Charged Compression Ignition engine with Di ethyl ether -Biodiesel-Butanol blend as Pilot fuel
Authors: Bansal Aaradhya , Chatterjee Debdutta , Pradhan Buland , Darshan Varun , Dan Reuben , Feroskhan M , Gobinath N
Published: October 2020

The continuous and increasing in volume of fossil fuels utilization leads to an alarming increase in green-house gases emissions. Consequentially, the release of toxic agents may cause detrimental health issues and aggravate global warming effects. Biofuels, due to its reduced emission effects, are found to be a potential alternate to fossil fuels, especially for their usage in internal combustion engines under certain loading conditions. The present research work aims at investigating the effects of butanol blending ratio at different biogas flow rates on the performance and emission characteristics of a single-cylinder CI (Compression ignition) engine under Homogenous Charge Compression Ignition (HCCI) mode. Flow rates of biogas taken in the present study are 12 lpm and 16 lpm whereas the butanol is blended in biodiesel – DEE (Diethyl-ether) mixture at 10, 20 & 30% concentration by volume. The engine parameters analysed in the present work are brake thermal efficiency, Brake Specific Energy Consumption (BSEC), Hydrocarbons (HC), Carbon monoxide (CO), Oxides of Nitrogen (NOx) and Smoke emissions. Results showed that the butanol addition in the fuel reduced the NOx emissions considerably at various loads between 0.1 N-m to 15 N-m. Further increase in load resulted in knocking conditions in the engine due to multipoint ignition. Based on the experiments, it is witnessed that 30% of butanol blend in biodiesel-DEE mixture high efficiency and low smoke emissions compared to all other blends. Simultaneous reduction of NOx and smoke emissions is observed in HCCI mode.
Experimental and Numerical investigation to Maintain the inside temperature of wooden Transport/storage box by incorporating Phase Change Material
Authors: Srusti Bhargava , Rajat S , Amar K , Daksh S , Shyam Kumar M.B.
Published: October 2020

Transport/storage box is to be used for storing the inorganic material under control environment. The main aim of this storage box is maintain the inside temperature during the transport in the production plant or customer place for the short duration of 1 to 2hrs. In general, during day or night times the interior temperature of storage box increases or decreases than the ambient temperature. This change in temperature can make the stored inorganic materials hazardous. A latent heat based storage system plays a major role in removing unwanted heat & maintaining the inside temperature of the storage box. Numerical and experimental studies were conducted to investigate the role of PCM in maintaining the temperature inside the wooden storage. Storage box is made by plywood and avoid the heat transfer from ambient. the sides and bottom walls are insulated by pasting the thermocol. Experimentation is carried out on the wooden box with no PCM and then with PCM. The operating conditions like solar radiation and ambient temperature is same for both the cases. PCM is placed horizontally on the Aluminium mesh, which is seated above the thermocol padding on top side. The experimental results showed that the box air temperature in the case of without PCM could be raised 42°C depending on how long the box is exposed to sunlight. In case of the wooden box with PCM the inside temperature of 37°C could be maintained for nearly one hour. Considering the same boundary conditions employed in experiments like sun radiation, ambient temperature, a 3D transient numerical simulation is carried out using ANSYS FLUENT. HYPERMESH is used for meshing the solid and fluid domain. Inside air and outside air is considered as fluid domain in the simulation. Both the experimental and numerical results were in variation with 1°C.
Sustainable Energy Solutions for Community Housing
Authors: Kamesh M.R. , Girish Kumar G S , Kiran C
Published: October 2020

With increasing population, it is resulting in faster depletion of combustible resources for energy, hence it is needed to implement renewable resources to cater to energy demands of community housings for a sustainable future. Our work integrates renewable resources like solar, wind along with grid energy to provide a hybrid system, to cater to the above stated energy needs. The above integration is done with the help of trial version of an energy software known as HOMER Energy Pro, which is used for microgrid and any dispersed power generation system planning and its effective development. This helps decide the best system configuration based on the geographic location and resources available, leading us to provide with a sustainable hybrid system solution for 250 average 2 BHK houses for the best possible economy and efficiency with a better future scope. Good improvement in Carbon Credit is seen.
Bamboo materials in cement, geopolymer and reinforced concrete as sustainable solutions for better tomorrow
Authors: Prem Kumar V , Vasugi V
Published: October 2020

It’s well known that due to increase in population and abundant use of materials, there is a scarcity of materials in the construction industry. In this modern era, people prefer to have a modern construction which made usage of conventional building materials abundantly. Though increase in the usage of these materials leads to the scarcity, it also opens way for an unsustainable environment. In order to overcome this both scarcity and environmental issue and to develop an eco-friendly environment, many researchers were going on to replace these building materials by any other natural material. Bamboo is one of the exact alternative materials to be replaced in the construction industry because of its mechanical and chemical properties. Bamboo has a major application in the construction industry and used in roofs, flooring, foundations, trusses etc. Bamboo is preferred as the best sustainable material and suggested for low cost housing projects. In this paper all the physical and mechanical properties of bamboo reinforced structural elements, influence of bamboo materials in cement and geopolymer concrete is reviewed.
Multiple Reactor System for Biohydrogen And Bioethanol Production
Authors: Maanav Charan K S , Shyam Kumar M B , Harish R
Published: October 2020

Hydrogen gas has proven to be an ideal green fuel. Its use is limited at present due to inefficient and harmful methods of production like steam-methane reformation and coal gasification. Systems that utilize hydrogen as a fuel can be considered practical only with the development of better, cost-efficient methods of its production. This study focuses on efficient mass production of bio-hydrogen (and bio-ethanol as a byproduct) for commercial utilization with a theoretical multiple reactor system. The process involves culturing of modified photosynthetic algae (such as Chlamydomonas reinhardtii) in bioreactors for bio hydrogen production. This process produces some waste algal cells. These can be sent to subsequent reactors for production of bio-ethanol by fermentation. Also, the waste algal cells need to undergo pyrolysis before the fermentation. Hydrogen is produced in this process too. All these factors put together improve the overall yield of the complete process and reduce its cost substantially. Though the model is theoretical, it can be adapted for commercial production of hydrogen. The hydrogen can, in turn, be used as fuel for powering fuel cells which have zero emission and hence, are environment-friendly.
Adoption of Integrated Solar System with Thermic fluid working medium for Parboiling Rice Mills in Tamilnadu
Authors: Vijayaraju K. , Bakthavatsalam A.K.
Published: October 2020

Tamilnadu is having more than 3000 rice processing or manufacturing units popularly known as Rice Mills. The typical Rice Mills are energy intensive and huge quantity of waste generation sector especially in sorting contaminants, parboiling process and husk removal. The two major process in the boiled rice manufacturing industry are Parboiling and Drying of paddy, in which steam is used as the thermal energy source through rice husk/firewood boilers having SEC(t) of 195- 280 kg/ton of paddy. Therefore Parboiled rice processing is considered to be water and energy intensive and therefore affects the environment significantly. The thermal energy consumption for par-boiled rice process is 2800- 3800MJ/ton paddy, of which 20-30% is for Parboiling process and steaming process and 60 -70% for paddy drying process. Several attempts were made already to adopt solar system as an alternative source of thermal energy which has been trailed for hot water and hot air generation separately. These approaches had resulted in increase in high investment with very low rate of return and resulted as a non attractive in economic terms. Hence, this study has been focused on study of thermal energy requirement of the above processes of rice mill and to check the viability of adoption of an integrated solar thermal system with thermic fluid as working medium. The expected outcomes of this study will be reduction of SEC(t) to be less than 100 kg/ton of paddy to null value and also to make carbon neutral.
A set of data on retrospective grain yield for neural network modeling
Authors: Rogachev A F , Melikhova E V , Belousov I S
Published: October 2020

Theoretical, methodological and applied aspects of creating a database (DB) of long-term retrospective information about the yield of grain crops are considered. The database is designed for statistical processing and modeling of multi-year data. Statistical information on annual levels of grain yield is the basis for planning, forecasting, management and optimization of agricultural production. To implement these tasks and their information support, we use design methods and models that allow us to build relational databases that provide statistical and neural network modeling of interannual variability of yield levels. The data storage format (*.csv) is justified, which provides in-depth processing and statistical analysis using built-in Python libraries. The review statistical analysis of productivity on the example of grain crops grouped by annual intervals is presented, and their features are revealed.