bluuebunny/crossref_metadata_2025_split huggingface dataset:
The study of solar neutrinos and of non-standard neutrino interactions with Borexino
Authors: Zavatarelli Sandra , Agostini M. , Altenmüller K. , Appel S. , Atroshchenko V. , Bagdasarian Z. , Basilico D. , Bellini G. , Benziger J. , Bick D. , Bonfini G. , Bravo D. , Caccianiga B. , Calaprice F. , Caminata A. , Cappelli L. , Cavalcante P. , Cavanna F. , Chepurnov A. , Choi K. , D’Angelo D. , Davini S. , Derbin A. , Di Giacinto A. , Di Marcello V. , Ding X.F. , Di Lüdovico A. , Di Noto L. , Drachnev I. , Formozov A. , Franco D. , Gabriele F. , Galbiati C. , Gschwender M. , Ghiano C. , Giammarchi M. , Goretti A. , Gromov M. , Güffanti D. , Hagner C. , Hungerford E. , Ianni Aldo , Ianni Andrea , Jany A. , Jeschke D. , Kumaran S. , Kobychev V. , Korga G. , Lachenmaier T. , Laubenstein M. , Litvinovich E. , Lombardi P. , Lomskaya I. , Ludhova L. , Lukyanchenko G. , Lukyanchenko L. , Machulin I. , Manuzio G. , Marcocci S. , Maricic J. , Martyn J. , Meroni E. , Meyer M. , Miramonti L. , Misiaszek M. , Muratova V. , Neumair B. , Nieslony M. , Oberauer L. , Orekhov V. , Ortica F. , Pallavicini M. , Papp L. , Penek O. , Pietrofaccia L. , Pilipenko N. , Pocar A. , Raikov G. , Ranalli M.T. , Ranucci G. , Razeto A. , Re A. , Redchuk M. , Romani A. , Rossi N. , Rottenanger S. , Schönert S. , Semenov D. , Skorokhvatov M. , Smirnov O. , Sotnikov A. , Suvorov Y. , Tartaglia R. , Testera G. , Thurn J. , Unzhakov E. , Vishneva A. , Vogelaar R.B. , von Feilitzsch F. , Wojcik M. , Wurm M. , Zaimidoroga O. , Zavatarelli S. , Zuber K. , Zuzel G. 
Published: May 2021

Abstract
The Borexino liquid scintillator neutrino observatory has a unique capability to perform high-precision solar neutrino observations thanks to its exceptional radiopurity and good energy resolution (5% at 1 MeV). A comprehensive study of the pp-chain neutrinos was presented that includes the direct measurements of 7Be, pp and pep neutrino fluxes with the highest precision ever achieved (down to 2.8% in the 7Be component), the 8B with the lowest energy threshold, the best limit on CNO neutrinos and the first Borexino limit on hep neutrinos. These results are important to validate the MSW-LMA oscillation paradigm across the full solar energy range and to exclude possible Non-Standard neutrino Interactions (NSIs). In particular the effects of neutrino-flavor-diagonal Neutral-Current (NC) interactions that modify the vee and vτe couplings while preserving their chiral and flavor structures, have been investigated. At detection, the shape of the electron-recoil spectrum is affected by changes in the vee and vτe couplings, quantified by the parameters

ε
e

L
/
R

and

ε
τ

L
/
R

. New bounds to all four parameters were obtained, quite stringent compared to the global ones. In particular, the best constraint to-date on

ε
e
L

was achieved. A comprehensive summary of all the recent results on solar neutrinos from Borexino is reported in the present paper.
KAGRA Cryogenic Suspension Control toward the Observation Run 3
Authors: Yamada Tomohiro 
Published: May 2021

Abstract
We have newly developed a vibration isolation system to reduce vibration via heat links, which would be one of the obstacles in the control of KAGRA gravitational wave detector. KAGRA adopts cryogenic mirrors for main optics to reduce thermal noise, which is a fundamental noise source in ground-based gravitational wave detectors in 100 Hz region, and achieves the best sensitivity in this frequency region in the world. The cryogenic mirror needs to be cooled down rapidly not to waste observation time and quietly not to disturb the mirror suspension system. For the former, radiative cooling works effectively with black coatings in high temperature region. Conductive cooling will strongly work with heat links in low temperature. However, according to our calculation, it was revealed that vibration via heat links impairs the detector sensitivity in several dozen Hz. The cryogenic suspension with heat links needs to be properly controlled up to almost same frequency region, thus, we have focused on reducing transmitting vibration with Heat Link Vibration Isolation System. In this paper, we will introduce the cryogenic suspension system, cooling system and Heat Link Vibration Isolation System in KAGRA.
Reduction of radioactive impurities from the liquid scintillator by using a Metal scavenger
Authors: Yuto KAMEI 
Published: May 2021

Abstract
The KamLAND2-Zen experiment is a future plan to perform the search for neutrinoless double-beta decay (0vββ) by using a large liquid-scintillator (LS) based detector, i.e., KamLAND2. The KamLAND detector will be upgraded by increasing the light yield of scintillation. One of the upgrade plans consists of using a new linear alkylbenzene (LAB) based LS. We have developed the LAB-LS radio-purification method by using a metal scavenger. The scavenging process resulted in a Pb-removal efficiency of 90.1±1.0% at most, and LS performance parametrics, such as light yield, light transparency, amount of radioactive impurities remaining, and the concentration of components were observed to be stable after scavenging. Therefore, it can be asserted that scavenging is a useful method for LS purification.
Improvement of Energy Estimator for KamLAND-Zen 800
Authors: Miyake Haruhiko 
Published: May 2021

Abstract
KamLAND-Zen 800 explores neutrinoless double beta decay(0vββ) of 136Xe. The experiment was started in January 2019 and data acquisition is going well. In the latest result of KamLAND-Zen 800 the most dominant background is 2vββ decay, which can be reduced by improvement of the detector energy resolution. In this study we aim to improve the energy resolution by optimizing the energy reconstruction method and reduce the 2vββ background by a factor of ~ 2/3.
Nanostructuring and intercrystalline adsorption of the workpiece surface during plastic deformation of metals
Authors: Petrov A P , Bespalov A V , Sokolov A V , Shlenskiy A G 
Published: May 2021

Abstract
In this paper it is shown that the combination of surface nanostructuring and subsequent plastic deformation can be a way to control the structure of the material and, accordingly, its mechanical properties by surface action.
The use of laser shock processing for extension of service life of critical units of aircraft engines after the foreign object damage
Authors: Sakhvadze G G , Pugachev M S , Sakhvadze Zh G 
Published: May 2021

Abstract
The authors study the change of the rate of growth of fatigue cracks that occur due to the damage of surface of an engine blade made of the alloy Ti-6Al-4V, previously processed by laser shockwaves, by foreign objects. The numerical study of the model of damaged laser-processed blade was performed by finite element method. The model developed took into consideration the residual stress fields that occurred due to the foreign object damage as well as the effect of the crack closure under compressive residual stresses. To cause the growth of fatigue cracks, the blade was stressed using real operation modes, including low-and high-cycle fatigue and the combination thereof. The residual stresses, previously inserted into laser shock processing blade surface, complicate the origin and growth of fatigue cracks after the foreign object damage, extending the service life of the blade and the entire engine.
Microstructure, fatigue strength and erosion resistance of MAX-phase embedded Ti-Si-B nanostructured coatings on Ti-6Al-4V
Authors: Teryaev D A , Shulov V A , Bytsenko O A , Lyakhovetskiy M A 
Published: May 2021

Abstract
Ti-Si-B nanostructured coatings were deposited on Ti-6Al-4V substrates by vacuum plasma processing with droplet separation. A composite Ti-Si-B cathode fabricated by self-propagating high temperature synthesis with subsequent hot pressing was used. The microstructure and mechanical properties of the obtained coatings were analysed by applying Auger-electron spectroscopy, X-ray diffraction and scanning electron microscopy methods accompanied by hardness measurements, fatigue strength and erosion resistance testing. It was established that Ti-Si-B nanostructured coating deposition leads to significant improvement of fatigue strength and erosion resistance of Ti-6Al-4V. A noticeable raise of the fatigue strength is attributed to presence of low dispersed Ti3SiB2 MAX-phase inclusions that suppress fatigue crack propagation.
Research Status and Development of Precision Analysis of CNC Machine Tools
Authors: Dou Yifan , Zhang Genbao , Ran Yan 
Published: May 2021

Abstract
Accuracy is a key quality characteristic of CNC machine tools, reflecting the pros and cons of machine tool performance. Accuracy is affected by performance failures of CNC machine tools, such as vibration, friction, and heat transfer. Therefore, it is difficult to accurately model and comprehensively analyse the accuracy of the machine tool by studying the influence of certain factors on the accuracy of the CNC machine tool in isolation, which makes it difficult to find out the problems in the design or manufacturing process. The article analyses the current status and research significance of domestic CNC machine tool accuracy, expounds the domestic and foreign research status of CNC machine tool accuracy modelling method and CNC machine tool accuracy comprehensive analysis, summarizes the existing problems and development trends of CNC machine tool accuracy research, and compares it based on the meta-action. The theoretical systematic modelling of the accuracy of CNC machine tools and the key issues of comprehensive evaluation of the accuracy of CNC machine tools combined with the meta-action chain provide insights and provide analytical methods for the design and manufacture of CNC machine tools.
Perovskite solar cell with improved performance passivated by all inorganic perovskite quantum dots
Authors: Cao Jia Xing , Shen Hui Feng , Cheng Lei , Zhao Wen Tao , Zhu Dong Huan , Sun Yan , Ni Bo 
Published: May 2021

Abstract
Improving the efficiency and stability of perovskite solar cells is the main direction of realizing their commercial application. Interface passivation is one of the most effective methods. Through interface passivation, on the one hand, the energy level of the device can be adjusted and the photoelectric conversion efficiency (PCE) of the device can be improved; on the other hand, materials that are not sensitive to the environment can be selected to improve the stability of the device. All inorganic perovskite quantum dots (QDs) have excellent environmental stability and are similar to the crystal structure of the absorbing layer of perovskite solar cells, so they have the potential for interface passivation. In this paper, two kinds of all inorganic perovskite QDs with different morphology, size and crystal structure were synthesized by hot injection method, which were used as the passivation layer of perovskite solar cells, and improved the device performance. The PCE of the device treated with CsPbBr3 QDs can reach as high as 20.45%, and has excellent environmental stability.
UAV 3D environment obstacle avoidance trajectory planning based on improved artificial potential field method
Authors: Yu Wenqiang , Lu Yonggeng 
Published: May 2021

Abstract
To address the inefficiency of the traditional artificial potential field method in complex environment for obstacle avoidance, the basic potential field function of the traditional artificial potential field method is improved, and the traditional spherical potential field is proposed to be improved to ellipsoidal potential field, and the improved algorithm is compared and simulated in MATLAB. The results show that the improved artificial potential field method satisfies the UAV to have high efficiency of safety and passability in obstacle avoidance trajectory planning in complex 3D environment.
The Effect on Carburizing Process on Microstructure and Properties of 20MnCr5 Gear Steel
Authors: Liang X. , Li X.J. , Lin X.Y. , Fan Z.Y. , Luo P. , Sun F.L. , Gao B.K. , Zhou T. , Du Q.N. , Xie H.S. 
Published: May 2021

Abstract
In this report, 20MnCr5 gear is characterized and analyzed under two carburizing heat treatment processes by optical microscope (OM) analysis, scanning electron microscope (SEM) analysis, X-ray diffraction (XRD) and Vickers hardness test. Results show that spherical and angular carbides can be obtained by a high concentration carburizing process for 20MnCr5 gear. Reheating and subsequent low-temperature tempering help refine the grains of the infiltration layer, reduce the residual austenite content in the permeable layer, and increase the thickness of the effective hardening layer.
Failure Analysis on Leakage and Perforation of Natural Gas Pipeline
Authors: Ju Jianbo , Du Liang , Meng Tao 
Published: May 2021

Abstract
CO2 corrosion is one of the most common corrosion forms in the process of oil and gas field development and oil and gas gathering and transportation. In the process of natural gas gathering and transportation, the problem of pipeline corrosion caused by CO2 is widespread, which often leads to serious local thinning, even perforation and fracture of the pipe body. Once it occurs, it will cause great economic losses and disastrous consequences to the actual production. Therefore, it is of great practical significance to study the mechanism of CO2 corrosion and analyze the influencing factors of CO2 corrosion in order to prevent the safety accidents and improve the efficiency of natural gas transportation. In this paper, a natural gas pipeline wall perforation failure analysis as an example, the sample from the natural gas pipeline corrosion product morphology and composition of micro analysis, and the CO2 corrosion mechanism, influencing factors and other aspects are described in detail.
Analysis of the Influence of Pit Unit Arrangement on the Drag Reduction Performance of Fish-scale Pits
Authors: Hou Jin-Ming , Shi Guang-Feng , Li Liang , Li hong-Da , Xia mingqiang 
Published: May 2021

Abstract
Apply Computational Fluid Dynamics (CFD) method to calculate the drag reduction effect of fish-scale pits with different arrangements under the same conditions. Through the analysis of wall shear stress, wall turbulence energy and axial velocity cloud diagram and velocity vector. It was found that the fish-scale pits can effectively reduce the shear stress and turbulent flow energy on the wall. At the same time, it was found that the bottom of the fish-scale pits formed tiny vortices flowing in the opposite direction. The “vortex cushion effect“ is combined with the “pushing effect“ caused by the friction generated by the bottom vortex, thereby reducing the friction. The research results show that the rhombus arrangement 2 can arrange a denser pit unit in the effective area to achieve a better drag reduction effect, and its drag reduction rate reaches 6.05%.
Experimental study of low-cycle fatigue of S30408 welded joints with strain strengthening
Authors: Si Jun , Ren Facai , Ren Bin 
Published: May 2021

Abstract
With the change of energy consumption structure, cryogenic liquids are increasingly widely used, such as liquefied natural gas (LNG), liquid hydrogen, liquid nitrogen, etc. Austenitic stainless steel is widely used in fabrication of cryogenic temperature pressure vessels as a kind of material with good lower temperature resistance. It is difficult to give full play to the high tensile strength and high plasticity reserve of austenitic stainless steel by using conventional design methods, which results in material waste and cost increase. The strain strengthening technology of austenitic stainless steel is the more effective method to realize the lightweight design and manufacture of cryogenic pressure vessel and reduce the cost. Fatigue damage is one of the typical failure modes of cryogenic pressure vessels. For the fatigue design of conventional pressure vessels, there are detailed standards, but there are few specific provisions for the fatigue design of strain strengthening pressure vessels. In this paper, experimental study on the low-cycle fatigue behavior of S30408 welded joints with 7% and 9% pre-tensile deformation were carried out.
Effect of process parameters on wall thinning of high strength 21-6-9 stainless steel tube in numerical control bending
Authors: Fang Jun , Ouyang Fang , Lu Shiqiang , Wang Kelu , Min Xuguang 
Published: May 2021

Abstract
Wall thinning, as one of the key defects determined directly the usability of the bent tube, should be strictly controlled. Elastic modulus changes with the plastic deformation and its influence the plastic forming quality of tube bending. To precisely predict the wall thinning of tube bending, a finite element (FE) model for numerical control (NC) bending of high strength 21-6-9 stainless steel tube (21-6-9-HS tube) was established considering the variation of elastic modulus. Using the model, the effects of process parameters on wall thinning of the 21-6-9-HS tube in NC bending were investigated. The results show that the variation of elastic modulus has no obvious effect on the change tendency of the wall thinning degree, but only increases the value of the wall thinning degree. The wall thinning degree enhances sharply at first, then occurs a platform deforming characteristics, and finally reduces abruptly from the bending section to the initial bending section, and it increases with the increase of the clearance of tube-bending die, the friction coefficient of tube-bending die and the friction coefficient of tube-wiper die or with the decrease of the clearance of tube-wiper die, but the increased degree is not significant in all conditions.
Influence of the North Branch of the Qingshuigou River on the Lower Reaches of Yellow River Based on Two-dimensional Numerical Model
Authors: Jiang Caodong , Ma Liangchao , Li Dongfeng , Zhang Hongwu , Li Zihao 
Published: May 2021

Abstract
The estuary regulation of the Yellow River is closely related to the regulation of the lower Yellow River. The flow and sediment entering the sea block the sediment entering the sea under the action of tidal rise and blocking sand, which has a significant impact on the flood control of the lower Yellow River. In the present study, there are many studies on the analysis of measured data and the empirical formula of inductive reasoning regression, and the use of two-dimensional mathematical model of water and sediment is still rare. In this study, based on the established mathematical model of marine water and sediment in the Yellow River estuary, the typical water and sediment conditions are selected to calculate the sediment movement and siltation erosion in the sea. The calculation results show that under the action of tide and blocking sand, the influence distance of the flow and sediment in the sea on the downstream river is about 90 km-110 km below the Luokou. The flow and sediment in the sea are mainly deposited in the range of 6-8 km along the direction of the flow in the sea near the entrance. The highest point of backwater is in the front of the blocking sand ridge. The backwater surface is relatively steep in the direction of the sea, and the backwater surface is relatively slow in the direction of the river.
Load balancing transmission technology of network communication based on phase spectrum compensation
Authors: Zhai Qian , Lu XingHua 
Published: May 2021

Abstract
In order to improve the load balance scheduling transmission ability of multi-frequency network communication in high-order nonlinear system, load balance design is needed. A load balance transmission method of multi-frequency network communication in high-order nonlinear system based on phase spectrum compensation is proposed. The time domain model of high-order nonlinear system multi-frequency network communication load is constructed by multi-frequency modulation phase spectrum compensation method. The feature detection of high-order nonlinear system multi-frequency network communication load is realized by high-order statistical feature connection identification and communication load balancing method. The autocorrelation constraint parameters of high-order nonlinear system multi-frequency network communication load are analyzed. The multi-dimensional array networking structure model of high-order nonlinear system multi-frequency network communication load is constructed by spatial spectral density analysis method. Combined with phase spectrum compensation and signal detection methods, the extracted high-order nonlinear system multi-frequency network communication load spectrum features are adaptively scheduled and filtered. In the wireless communication networking environment, load balance transmission of communication load in multi-frequency network of high-order nonlinear system is realized. The simulation results show that this method has better balance and lower error rate in multi-frequency network communication load balancing transmission, which improves the accuracy of multi-frequency network communication load balancing scheduling in high-order nonlinear systems.
Study on Properties of Flame-Retardant Plywood Made with Eucalyptus, Birch and Poplar Wood
Authors: Yin Chaolu , Zhang Xiang , Li Pingli , Fu Fuxin 
Published: May 2021

Abstract
In this work, the laboratory-made flame-retardant polyvinyl alcohol adhesive was used to prepare flame-retardant plywood made with eucalyptus, birch and poplar respectively, and the effect of tree species on the mechanical properties and flame-retardant properties of flame-retardant plywood was studied. The static bending strength data showed that the tree species had an obvious effect on the mechanical properties of the flame-retardant plywood, the flame-retardant plywood made with eucalyptus had the highest static bending strength, and the sample made with poplar had the lowest static bending strength. The results of the SBI test are consistent with the results of the LOI test, both indicated that the tree species had a significant effect on the flame-retardant properties of the flame-retardant plywood, the flame-retardant plywood made with poplar veneer has the highest LOI value, lowest FIGRA0.2MJ value and lowest THR
600s value.
Study on Performance of Cabin Air filters Under Different Work Conditions
Authors: Wei Shuhong , He Yongao , Yin Wei , Tian Cheng , Jiao Pengfei , Bian Jiachen 
Published: May 2021

Abstract
The in-vehicle air quality has increasingly attracted the attention of people. Hence, air filter performance under actual work conditions demonstrates remarkable significance. It is verified that the electrostatic adsorption can dramatically enhance the fractional efficiency of small-particle pollutants without increasing the pressure loss; as regard a lack of fractional efficiency test on the filter during the whole life cycle in current standards, the paper studied the tendency of filter’s fractional efficiency variation in the whole life cycle and discovered that fractional efficiency of small particles decreased first after increase due to the shielding of electrostatic charge; the tests on different air speed and area of filtered paper were carried out, showing that increasing the area of filtered paper can significantly lower the pressure loss and increase the filtration efficiency, which is of vital significance to provide the reference for further improving the performance of cabin air filter.