bluuebunny/crossref_metadata_2025_split huggingface dataset:
Impact of climate change on pests of rice and cassava
Authors: Chaya Mona , Xiang Tao , Green Ashley , Gu Baogen 
Published: November 2021

Abstract

Climate change is exacerbating food insecurity, and its negative impacts will worsen over time. This is happening via several pathways, among which plant pests are a leading cause. To contribute to more evidence-based decisions and policies, a team from the Food and Agriculture Organization of the United Nations (FAO) carried out a comprehensive literature review on rice (
Oryza sativa
) and cassava (
Manihot esculenta
), the major pests and diseases affecting them, and the impact of climate change on the latter. Rice is the major staple crop for about half the world’s population. Most studies conclude that pest pressure will increase on rice under future climate change. There are a lot of pests of rice, among which brown planthopper (
Nilaparvata lugens
) is the most important pest. Leaf blast disease caused by fungus Magnaporthe grisea is the most significant disease, with losses of up to USD 66 billion dollars per year that are equivalent to the amount needed to feed 60 million people. Cassava is the major staple crop and crucial for food security in many countries of the world. A study has shown that cassava production will vary from −3.5% to +17.5% within Africa under 2030 climate projections. Unfortunately, as other crops, cassava will be vulnerable to pests and diseases. Over a third of attainable cassava yield is lost every year to pests and disease alone.
Highly sensitive fiber-optic SPR sensor with surface coated TiO2/MWCNT composite film for hydrogen sulfide gas detection
Authors: Chen Rong , Lan Guilian , Wang Ning , Yan Wenjing , Yi Jueming , Wei Wei 
Published: November 2021

Abstract
Hydrogen sulfide (H2S) gas has a severe effect on the respiratory system of the human body and ambient environment, necessitating development of on-line H2S gas sensors with high performance for safety and health concerns. Here, we proposed a fiber-optic surface plasmon resonance sensor for H2S detection employing TiO2 nanoparticles and multilayer carbon nanotubes composite (TiO2/MWCNT) as sensing film, featuring desirable advantages of high sensitivity, selectivity, and real-time detection. Benefiting from special structure and large specific surface area of MWCNTs, the adsorption capacity of sensing surface to gas molecules can be significantly enhanced. Moreover, the high carrier mobility of MWCNTs can further promote the charge transfer between TiO2 and H2S. These unique features of TiO2/MWCNT composite film result in an obvious improvement of sensitivity for H2S detection. Experimental results show that the maximum sensitivity of 21.76 pm ppm−1 (picometer/part-per-million) and detection limit of 0.2 ppm can be obtained by appropriately optimizing the componential constitutions of TiO2/MWCNT composite. Such detection limit is strikingly lower than the threshold concentrations in workplace set by Federal Institute for Occupational Safety (10 ppm). In addition, the favorable selectivity, response/recovery times, repeatability and stability were demonstrated as well. This facile and cost-effective work provides a novel strategy for constructing high performance H2S gas sensor with fast response and real-time detection, which has prospective application in the fields of human health and environmental conservation.
The effects of the driving frequencies on micro atmospheric pressure He/N2 plasma jets driven by tailored voltage waveforms
Authors: Hübner G , Bischoff L , Korolov I , Donkó Z , Leimkühler M , Liu Y , Böke M , Schulz-von der Gathen V , Mussenbrock T , Schulze J 
Published: November 2021

Abstract
Capacitively coupled micro atmospheric pressure plasma jets are important tools for the generation of radicals at room temperature for various applications. Voltage waveform tailoring (VWT), which is based on the simultaneous use of a set of excitation frequencies, has been demonstrated to provide an efficient control of the electron energy probability function (EEPF) in such plasmas and, thus, allows optimizing the electron impact driven excitation and dissociation processes as compared to the classical single-frequency operation mode. In this work, the effects of changing the driving frequencies on the spatio-temporally resolved electron power absorption dynamics, the generation of helium metastables and the dissociation of nitrogen molecules are investigated in He/N2 plasmas based on experiments and simulations. We find that under a single-frequency excitation, the plasma and helium metastable densities are enhanced as a function of the driving frequency at a fixed voltage. When using valleys-type driving voltage waveforms synthesized based on consecutive harmonics of the fundamental driving frequency, the spatial symmetry of the electron power absorption dynamics and of the metastable density profile is broken. Increasing the fundamental frequency at a constant voltage is found to drastically enhance the plasma and metastable densities, which is a consequence of the change of the EEPF. Finally, we compare the energy efficiency of the formation of radicals under single-frequency and VWT operation at different driving frequencies. For a given power dissipated in the plasma, VWT yields a higher helium metastable as well as electron density and a higher dissociation rate of N2.
Multi-robot cardinality-balanced multi-Bernoulli filter simultaneous localization and mapping method
Authors: Zhang Zijing , Zhang Fei , Ji Chuantang 
Published: November 2021

Abstract
In order to improve the simultaneous localization and mapping (SLAM) accuracy of mobile robots in complex indoor environments, the multi-robot cardinality-balanced multi-Bernoulli filter SLAM (MR-CBMber-SLAM) method is proposed. First of all, this method introduces a multi-Bernoulli filter based on the random finite set (RFS) theory to solve the complex data association problem. This method aims to overcome the problem that the multi-Bernoulli filter will overestimate the aspect of SLAM map feature estimation, and combines the strategy of balancing cardinality with a multi-Bernoulli filter. What is more, in order to further improve the accuracy and operating efficiency of SLAM, a multi-robot strategy and a multi-robot Gaussian information-fusion method are proposed. In the experiment, the MR-CBMber-SLAM method is compared with the multi-vehicle probability hypothesis density SLAM (MV-PHD-SLAM) method. The experimental results show that the MR-CBMber-SLAM method is better than MV-PHD-SLAM method. Therefore, it effectively verifies that the MR-CBMber-SLAM method is more adaptable to a complex indoor environment.
Tailoring the properties of Ni-Mn based NTC thermistors by Cu and Li addition
Authors: V K Haripriya , V S Sharon , K A Malini 
Published: November 2021

Abstract
The influence of Cu and Li doping in the structural and R-T characteristics of Ni-Mn-based spinel oxide negative temperature coefficient (NTC) thermistors prepared using the conventional solid-state synthesis method was investigated in this study. The doping of Cu and Li in nickel manganite plays an important role in tailoring the thermistor parameters. The structural characterization of the prepared samples using XRD revealed that the basic structure of the samples is not altered by the addition of the dopants Cu and Li. The particle size of the samples was obtained at less than 50 nm. R-T characteristics showed a decrease in resistance with temperature. It was observed that the addition of dopant Cu in a minimal amount helps to tune the resistance of the thermistor in the required range and Li addition, as a dopant, stabilized the thermistor parameters B and alpha.
Multilayer analysis of immiscible power-law fluids under magnetohydrodynamic and pressure-driven effects in a microchannel
Authors: Gómez J R , Escandón J P , Hernández C G , Vargas R O , Torres D A 
Published: November 2021

Abstract
In the present study, the combined magnetohydrodynamic and pressure-driven flow of multilayer immiscible fluids into a parallel flat plate microchannel is semi-analytically solved. Due to the handling of complex fluids in various microfluidic platform applications, the fluid transport reviewed here considers the power-law model. The movement of electrically conductive fluid layers is due to Lorentz forces that arise from the interaction between an electric current and a magnetic field. To find a solution for the flow field, the momentum equation and the rheological model for each fluid layer, together with the corresponding boundary conditions at the liquid-liquid and solid-liquid interfaces, are solved simultaneously through a closed system of nonlinear equations. The graphical results show the influence of the dimensionless parameters that arise from the mathematical modeling on the velocity profiles and flow rate. These are the magnetic parameters, the fluid layers thickness, the viscosity coefficients, the ratios between pressure forces and magnetic forces, and the flow behavior indexes. This theoretical work contributes to the design of microfluidic devices for flow-focusing tasks in chemical, clinical, and biological areas.
Nanotube formation from self-curling nanofilms driven by intrinsic surface-stress imbalance
Authors: Li Jiangang , Yao Haiyan , Xu Yaodong , Gao Zhixiang , Wang Hua , Shi Yunlong 
Published: November 2021

Abstract
The theoretical analysis for fabricating nanotubes from self-curling of nanofilms due to intrinsic surface stress imbalance was given in this paper. A nanofilm was curled into a nanotube along tangential direction, while the other in-plane direction (cylindrical direction) was only elongated but wasn’t curled or bent. Film bending behavior is usually described by using Stoney formula, but the Poisson’s effect of cylindrical direction should be considered for describing mechanical behavior of curling up phenomenon. Stoney formula assumes that the surface stress is isotropic and the bending is also isotropic, but the shape of nanotube is anisotropic. On the other hand, surface effects and symmetry lowering effect strongly affect the mechanical properties of nonafilms. Here, we gave a more accurate curling theory by including surface stress, surface elasticity, symmetry lowering and Poisson’s effect of cylindrical direction.
Scalar fields near compact objects: resummation versus UV completion
Authors: Davis Anne-Christine , Melville Scott 
Published: November 2021

Abstract
Low-energy effective field theories containing a light scalar field are used extensively in cosmology, but often there is a tension between embedding such theories in a healthy UV completion and achieving a phenomenologically viable screening mechanism in the IR.

Here, we identify the range of interaction couplings which allow for a smooth resummation of classical non-linearities (necessary for kinetic/Vainshtein-type screening), and compare this with the range allowed by unitarity, causality and locality in the underlying UV theory.
The latter region is identified using positivity bounds on the 2→2 scattering amplitude, and in particular by considering scattering about a non-trivial background for the scalar we are able to place constraints on interactions at all orders in the field (beyond quartic order).
We identify two classes of theories can both exhibit screening and satisfy existing positivity bounds, namely scalar-tensor theories of P(X) or quartic Horndeski type in which the leading interaction contains an odd power of X.
Finally, for the quartic DBI Galileon (equivalent to a disformally coupled scalar in the Einstein frame),
the analogous resummation can be performed near two-body systems and imposing positivity constraints introduces a non-perturbative ambiguity in the screened scalar profile.
These results will guide future searches for UV complete models which exhibit screening of fifth forces in the IR.
Dynamical screening effects on big bang nucleosynthesis
Authors: Hwang Eunseok , Jang Dukjae , Park Kiwan , Kusakabe Motohiko , Kajino Toshitaka , Balantekin A. Baha , Maruyama Tomoyuki , Ryu Chang-Mo , Cheoun Myung-Ki 
Published: November 2021

Abstract
A moving ion in plasma creates a deformed electric potential depending on the ion velocity, which leads to the distinct screening effect compared to the standard static Salpeter formula. In this paper, adopting the test charge method, we explore the dynamical screening effects on big bang nucleosynthesis (BBN). We find that the high temperature in the early universe causes the ion velocity to be faster than the solar condition so that the electric potential is effectively polarized. However, the low density of background plasma components significantly suppresses the dynamical screening effects on thermonuclear reaction rates during the BBN epoch. We compare our results with several thermonuclear reaction rates for solar fusion considering the dynamical screening effects. Also, we discuss the additional plasma properties in other astrophysical sites for the possible expansion from the present calculation in the future.
Organic electrolytic photocapacitors for stimulation of the mouse somatosensory cortex
Authors: Missey Florian , Botzanowski Boris , Migliaccio Ludovico , Acerbo Emma , Głowacki Eric Daniel , Williamson Adam 
Published: November 2021

Abstract

Objective. For decades electrical stimulation has been used in neuroscience to investigate brain networks and been deployed clinically as a mode of therapy. Classically, all methods of electrical stimulation require implanted electrodes to be connected in some manner to an apparatus which provides power for the stimulation itself. Approach. We show the use of novel organic electronic devices, specifically organic electrolytic photocapacitors (OEPCs), which can be activated when illuminated with deep-red wavelengths of light and correspondingly do not require connections with external wires or power supplies when implanted at various depths in vivo. Main results. We stimulated cortical brain tissue of mice with devices implanted subcutaneously, as well as beneath both the skin and skull to demonstrate a wireless stimulation of the whisker motor cortex. Devices induced both a behavior response (whisker movement) and a sensory response in the corresponding sensory cortex. Additionally, we showed that coating OEPCs with a thin layer of a conducting polymer formulation (PEDOT:PSS) significantly increases their charge storage capacity, and can be used to further optimize the applied photoelectrical stimulation. Significance. Overall, this new technology can provide an on-demand electrical stimulation by simply using an OEPC and a deep-red wavelength illumination. Wires and interconnects to provide power to implanted neurostimulation electrodes are often problematic in freely-moving animal research and with implanted electrodes for long-term therapy in patients. Our wireless brain stimulation opens new perspectives for wireless electrical stimulation for applications in fundamental neurostimulation and in chronic therapy.
On the dynamic effects of evaporation and boiling of drops on inhomogeneous graphene substrates for effective thermal management of energy devices
Authors: Babenko D D , Dmitriev A S , Mikhailova I A 
Published: November 2021

Abstract

This research examines thermal performance of metal-graphene nanocomposites for thermal management. Graphene nanoflakes and graphite microparticles were compressed with cooper meshes under different pressures. The prepared samples were characterized using optical microscopy. The fabricated samples of cooper-graphene composites were studied to determine the droplet evaporation rates and contact angles at different temperatures including film boiling.
Power spectra of pressure pulsations in the processes of evaporation/boiling of a liquid at low pressures
Authors: Brester A E , Zhukov V I , Shvetsov D A , Pavlenko A N 
Published: November 2021

Abstract

This paper presents experimental data on pressure fluctuations during evaporation/boiling of a thin liquid film under conditions of reduced pressure. The experimental data were obtained as a result of studying heat transfer on a smooth horizontal surface in a wide range of changes in the height of the liquid layer. Using the fast Fourier transform, the power spectra of pressure pulsations versus frequency were obtained. It was found that the power spectra of pressure pulsations differ depending on the mode of evaporation/boiling in the system.
Non-trivial capillary hydrodynamics and strong evaporative cooling in multilayer two-dimensional materials: application in thermal management systems of electronic and energy devices
Authors: Dmitriev A S 
Published: November 2021

Abstract
Studies of evaporation from graphene nanostructures with nontrivial capillary hydrodynamics are being carried out. Data were obtained for the rates of evaporation and heat fluxes during cooling of experimental heated cells. Models were built and compared with experimental data. It is shown that the existing models overestimate the evaporation rates and heat fluxes and heat transfer coefficients.
Modelling the hydrodynamics of a two-phase flow in the non-Newtonian fluid
Authors: Kozhukhova E A , Kozhukhov N N , Ryazhskikh V I , Naumov A M , Netreba A V 
Published: November 2021

Abstract
The paper presents the results of modelling the flow of droplets in the flow of a non-Newtonian fluid. The task is solved in a nonstationary formulation. We determined the time of stabilization of the speed profile of the droplets and the length of the initial hydrodynamic sector. We compared the specified characteristics for the main flow of the non-Newtonian fluid and for the set of droplets in the flow. We show the coincidence of the lengths of the initial hydrodynamic sections determined by the stabilization of speeds for the droplets and the non-Newtonian medium.
Modern approaches to the intensification of heat and mass exchange in multi-temperature condensation filters
Authors: Malevany M V , Konovalov D A 
Published: November 2021

AbstractThe article considers the problems and features of heat and mass exchange on developed surfaces in the conditions of both single-phase and vapour-liquid flow during its condensation. We give a brief analytical review of studies of hydrodynamics and heat exchange in such systems. We analyzed the efficiency of the working channel of the condensation filter and identified problematic points. We offer possible methods for intensifying heat and mass transfer on working surfaces.
Flow and heat transfer near a cylinders row
Authors: Mityakov A V , Gusakov A A , Grekov M A , Seroshtanov V V 
Published: November 2021

Abstract
The paper aims to investigate the dependence of heat transfer classification on the Reynolds number (Re) during flow around circular heated cylinders row. The investigated range of Re number varies from 4.5×103 up to 42×103. The distance between cylinders S was changed from 0.5d to 4d (where d is the cylinders dia). Cylinders surface temperature was kept constant. For each Re number, the case when the cylinders were mounted one after the other was investigated. To measure heat transfer and flow parameters (velocity, heat flux and heat transfer coefficient) near and at the cylinders surface, two experimental methods were used: gradient heatmetry and PIV. Heat flux and velocity fields were obtained from gradient heatmetry and PIV results, based on which the flow mode could be determined and compared with heat transfer mode. As a result, it was found that heat transfer is influenced by both the Reynolds number and the distance between the cylinders. The observed features are associated with influence on characteristics such as separation point location, boundary layer thickness, change in flow between the cylinders and vortices formation.
Investigation of the influence of narrowing annular channel and Reynolds number on formation of Tayler-Gortler vortexes
Authors: Pankratov E V 
Published: November 2021

Abstract
Abstract. The article investigates the Taylor-Gortler vortices arising in a swirling flow when the annular channel narrows. Several options for the geometry of the narrowed annular channel are researched. In the first case, the outer cylinder with a constant diameter and the inner cone with a variable cone angle are considered. In the second case, on the contrary an inner cylinder with a constant diameter and an outer cone with a variable cone angle are considered. All geometries were tested at different Reynolds numbers Re. = 8.3-103…21•103. As a result, the analysis of the propagation of secondary vortices along the length of the annular channel is presented.
Investigation of the influence of Taylor-Gortler vortexes on heat transfer of annular channel
Authors: Pankratov E V 
Published: November 2021

Abstract
This article is about the influence of Taylor-Gortler vortices on heat transfer in concentric annular channels with turbulent decaying swirling flows. The study shows that the occurrence and transformation of secondary vortex structures has a significant effect on the distribution of heat flux over the annular channel surface. An explicit is relationship between the radial velocity fluctuations and the heat flux density distribution. The highest intensity of heat transfer on the outer surface is observed in the areas of positive radial velocity values, while on the inner surface it is observed in the areas of negative radial velocity values.
Method for calculating the critical heat flux at pool boiling on structured surfaces
Authors: Stupakova A V , Dedov A V 
Published: November 2021

Abstract
A method of the critical heat flux enhancements at pool boiling using rough structures of various regular and irregular geometries is investigated. The experimental data are compared, and the critical heat flux is calculated since the V. V. Yagov model, which considers the additional inflow of liquid into the evaporation zone due to the action of capillary forces in the porous space. Based on the comparison of experimental and calculated data, it is concluded that the model is not universal for all microstructured surfaces. Recommendations for the calculation are given.
Modeling of vapor bubble growth at subatmospheric pressures
Authors: Vladyko I V , Malakhov I P , Surtaev A S , Pil’nik A A , Chernov A A 
Published: November 2021

Abstract
In this paper, the results of numerical calculations of a vapor bubble growth in superheated water at different pressures are presented. Modeling is based on a previously developed by the authors semi-analytical solution. The results are verified by experimental data obtained at atmospheric and subatmospheric pressures. The presented simulation results and experimental data are in good agreement. The advantage of the solution over the earlier ones (based on the thermal growth model) is shown.
Analytical solution to the problem of diffusion of the light component of the binary gas mixture in a plane channel
Authors: Popov V N , Popov I V 
Published: November 2021

Abstract
Within the framework of the kinetic approach, an analytical solution to the problem of diffusion of the light component of a binary mixture in a flat channel with infinite parallel walls is constructed. It is assumed that the mass of light component molecules and their concentration is much less than the mass of molecules and the concentration of heavy components. The flow rate of the heavy component is assumed to be zero. The change in the state of a light gas component is described on the basis of the BGK (Bhatnagar, Gross, Kruk) model of the Boltzmann kinetic equation. The diffuse reflection model is used as a boundary condition on the channel walls. The mass velocity profile of the light gas component is constructed. The flow rate of the light gas component per unit channel width is calculated. A comparison with similar results presented in open sources was done.