bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on the gas emission width of coal seam pressure released by goaf in the deep mine
Authors: Li Siqian , Cao Jianjun , Xie Yonglei
Published: June 2021

The technology of driving along goaf has been widely used in the prevention of high ground stress and coal-gasoutburst in coal mining in our country. In this paper, the 11-2 Coal Seam of zhujixi coal mine is taken as the research object. Based on the test of drilling cuttings and residual gas content at different depths of solid coal at the goaf side and the research on the distribution law, it is concluded that the effective pressure relief drainage belt width at the goaf side of 11-2 Coal Seam after mining is 29m. Field practice has been carried out in the adjacent working face. The results show that the predicted indexes measured during the coal roadway driving period do not exceed the specified critical value, which verifies the rationality of the width of the discharge zone. The results provide a theoretical support for the reasonable layout of the continuous working face, improve the driving speed of the coal roadway, reduce the cost of gas control, improve the economic benefits of the mine, and ensure the safety production of the mine.
Research on Vision-based Position Measurement System for Rocket Propellant Loading
Authors: Han Tao , Dacheng Cong
Published: June 2021

In the process of rocket propellant loading, the propellant's own gravity and wind pendulum may cause the connector to exert a large force on the rocket body, which may lead to connector disconnection and fuel leakage, or even damage to the rocket body. To improve the reliability and safety of rocket propellant loading, a position measurement system based on dynamic orientation detection alignment technology is proposed to achieve tracking of the rocket refueling port. In this paper, the two-dimensional position of the target in the camera plane is quickly extracted by identifying the direction of the target image and the size of the marker in the image, while the distance between the target and the camera is accurately obtained by a laser rangefinder. With this measurement solution, the deviation of the connector from the propellant filler port at the current moment can be modified in real time, thus reducing the forces on the rocket and increasing its launch reliability.
Extraction of Anthocyanin from Eggplant Peel by Ultrasonic Assisted Method and Application in Cosmetics
Authors: Fu Xiaofen , Zhu Chunli , Shen Ao , Fan Weixi , Shan Chaoyue
Published: June 2021

The anthocyanin of eggplant skin was extracted by ultrasonic assisted method. Single factor experiment and orthogonal optimization experiment were used to optimize the extraction factors of anthocyanin from eggplant peel. The results showed that the optimum extraction of anthocyanin from eggplant peel was obtained by orthogonal experiment under the condition of feed-liquid ratio of 13:15, time of 40 min, and temperature of 50ºC. The anthocyanin is stable by treating 1 min after 100ºC.
Current situation and development trend of traceability system of hazardous chemicals in China
Authors: Su Teng , Liu Chang , Zhou Ru
Published: June 2021

The traceability system of hazardous chemicals is a kind of information identification and tracking technology, which mainly involves the collection and management of the whole life cycle and whole chain information of hazardous chemicals. As an important means of safety supervision of hazardous chemicals, it is conducive to the long-term development of enterprises and the improvement of public safety. At present, the safety situation of China's chemical industry is grim. It is urgent to establish a practical and effective traceability system of hazardous chemicals to eliminate the obstacles of information acquisition of hazardous chemicals, strengthen safety supervision and enhance the ability of emergency response. This paper summarizes the development process, Traceability Technology and traceability development trend of China's hazardous chemicals traceability system, and puts forward some suggestions for improving and perfecting China's hazardous chemicals traceability system.
Study on Adsorption of Dye Wastewater by Modified Fly Ash
Authors: Qu Yanping , Yan Dongqing , Su Rushuang , Hu Wenshuo , Dai Yanyan
Published: June 2021

Used fly ash as raw material, it was modified by acid, alkali and high temperature to produce modified fly ash adsorbent, sulfuric acid modified fly ash adsorbent, sodium hydroxide modified fly ash adsorbent and high temperature modified fly ash adsorbent. In this paper, the effects of adsorbent dosage, adsorbent adsorption time, initial dye concentration, wastewater pH and temperature on dye adsorption were studied. The results showed that: the acid modified fly ash adsorbent had a good treatment effect on the dye; when the dosage of fly ash was 1.00 g, the adsorption time was 90 min, the pH of wastewater was 4, and the temperature was 45 °C, the decolorization rate of 60 mg/L methyl orange dye can reached more than 70%; when the dosage of fly ash was 0.20 g, the adsorption time was 60 min, the pH of wastewater was 3, and the temperature was 35 °C, the decolorization rate of 20 mg/L methyl orange dye can be achieved. The decolorization rate of Congo red can reached more than 80%.
Investigation of Biometric Identification Technology Based on biological Fingerprints and Facial Features
Authors: Li Huixing , Xue Yan , Zeng Xiancai
Published: June 2021

Biometric identification is largely dependent on feature extraction technology. As feature extraction techniques are increasingly mature, scholars have gradually turned their attention to the relevant problems between biometric characteristics. This paper reviews the characteristic extraction method of face and fingerprint analyzes the feature classification extraction method based on empirical knowledge and the depth learning-based computer logic sampling extraction method and compares existing solutions from the angle of image processing. Based on feature extraction, it will have prospected in the future biometric identification model of progress.
The research of the energy and the fluence of the primary and the secondary γ-ray in the n/γ hybrid radiation field
Authors: Guan ZhiYuan , Xu Mei
Published: June 2021

According to the "little boy" data from the United States, this paper simulates the primary γ-ray of the nuclear explosion and the secondary γ-ray produced by neutron, γ-ray and material interaction. At the same time, the linear attenuation coefficient spectra of 0.001mev to 100mev was calculated. The information was obtained from the point of the source projection of 500 meters to 1km. The results showed in the observation distance: The attenuation of the primary γ-ray energy was in line with the spectral γ-ray passing through the law of shielding the decay of the material. and it showed the phenomenon of the "hardening" of the energy spectrum. The fluence decreases an order of magnitude. The energy of the secondary γ-ray does not showed obvious attenuation laws, and the fluence decreases by about two orders of magnitude. It was worth noting that the average energy of the two kinds of γ-ray was around 2.100 MeV, and the fluence was in the same order of magnitude at 1km from the distance simulation.
Welding procedure research of white copper heat exchanger
Authors: Chengjun Jiang , Gaoping Fan , Xiaolong Xue , Xiaoli Zhang , Yannan Du
Published: June 2021

In order to satisfy the corrosion resistance requirement, the original pipe material of a heat exchanger is replaced by BFe30-1-1white copper. Based on analysis of the welding characteristics, joint structure and factors affecting the welding quality of BFe30-1-1 tube-to-tubesheet, the welding procedure is made. The morphology inspection, test of pull-off strength, metallographic structure examination and hardness test of the tube-to-tubesheet joints which is welded according to the welding procedure, can satisfy the standard and design requirements. The success of the test provides a good reference for the welding quality control of white copper heat exchangers.
The anode oxidation reaction in fuel cell: A DFT study
Authors: Ye Chenqing , Xie Yichun , Zheng Liping , Lin Yuxiang , Guo Weixiang , Qi Xueqiang
Published: June 2021

Although fuel cell (FC) has been regarded as promising “green” power generator, the Pt-based catalysts in the FC hampered their further development for its high cost and scarcity. Direct methanol fuel cell (DMFC) as another kind of proton exchange membrane fuel cell (PEMFC) has been manifested that Pd also performs a certain activity for methanol oxidation reaction (MOR). To better know the mechanism of MOR, we present a DFT study on the first step reaction of MOR on the Pd(111). The results show that methanol prefers to physically adsorb on the Pd(111) through oxygen atom, while the dehydrogenated hydrogen atoms can adsorb either on face-cantered cubic (FCC) or hexagonal close packed (HCP) sites. The intermediate products will form a much stronger interaction with the Pd(111) since they contain more unsaturated bonds. The energy barrier of O-H bond scission is most favourable, while the C-O bond is unfavourable in the first step of MOR.
Study on Kinetics of GD Hydrolysis in HCl aqueous
Authors: Wu Shaoxiong , Zhang Hongpeng , Miao Ting , Zhu Haiyan , Wang Lianyuan , Ge Liang
Published: June 2021

Organophosphate neurotoxic agents like Sarin (GB) and Soman (GD) are lethal to person. Except various kinds of decontaminants, they can be also decomposed in natural environment through nucleophilic reaction, where acidic or alkaline substance was to accelerate their hydrolysis. Most of the papers were about GB hydrolysis. Information on GD hydrolysis was relatively small, especially about kinetics of GD in acidic solution. In view of possible effect of positive ion and negative ion on hydrolysis reaction, a relatively simple composes solution, HCl aqueous solutions, was selected to investigate the factors affecting GD hydrolysis rate. Results showed that GD hydrolysis was accorded with the first-order kinetics equation if pH value was kept constant. Its rate constant was independent of GD initial concentration when the amount of H+ was excess than its requested amount. The apparent hydrolysis rate constant (kobs) in pH of 0.90 was about 0.202 min-1 at 20°C, no matter what initial concentration of GD was. The concentration of H+ was the most important factor affecting its rate. The rate constant (kobs) in HCl aqueous as a function of pH value (0.90~2.80) obeyed an equation in 25°C, that is kobs =0.17×10-0.82×pH. Reaction temperature had an obvious effect on hydrolysis rate of GD. Every 10°C increase in temperature, kobs of GD hydrolysis was improved about 2.5 times. The activation energy value (Ea) of GD hydrolysis in HCl aqueous with a pH value of 0.90 was approximately 64.25 kJ/mol.
Study on heat transfer enhancement of finned tube boiling in water tank
Authors: Duan Yapeng , Wang Xuesheng
Published: June 2021

A passive residual heat removal heat exchanger (PRHR HX) was used as the research object, and an experimental device with heat conduction oil as the heat source was set up to complete the experimental study of the outside tube saturation boiling. The improved Wilson diagram method was used to calculate the experimental data, and the heat transfer law of the outside tube boiling of smooth tube and finned tube was obtained. Compared with the two types of tubes, the intensification rate of smooth tube was 1.07, and that of finned tube was 2.39, and the finned tube was 2.23 times that of smooth tube. According to the intensification rate, the Nu modification of the heat transfer coefficient of the two tubes was further obtained.
Experimental study on performance of high purity nitrogen supply system in liquefaction unit of low concentration coalbed methane
Authors: Jia Xiao-liang
Published: June 2021

Aiming at the problems such as low CBM utilization rate caused by low concentration CBM with methane content less than 8% extracted from a small coal mine in Hancheng mining area, Shaanxi Province, and serious environmental pollution caused by coal-fired hot blast stove for heating, the heat storage and oxidation heating technology of ultra-low concentration gas in small coal mine was studied by combining field investigation and heat balance calculation. This technology replaces the coal-fired hot blast stove, realizes “coal and CBM mining and sharing” in the coal mine, and constructs a virtuous cycle development of “promoting drainage by using and promoting safety by drainage”. The research shows that: the scheme improves the utilization rate of CBM in the mining area, cancels the consumption of coal combustion, and can use 2.59 million Nm3 of pure CBM every year, generating 1.95 million yuan of economic benefits. And the emissions reduction of CO2 equivalent is 36000 tons. The benefits of safety, economy and environmental protection are remarkable. This technology is especially suitable for the utilization of ultra-low concentration CBM whose concentration is less than 8%, which has practical significance to improve the CBM utilization rate and promote the realization of the goal of “zero emission”.
The value of information sharing in a dual-channel closed-loop supply chain
Authors: Huang Yanting , Zheng Benrong , Wang Zongjun
Published: June 2021

This paper considers a dual-channel closed-loop supply chain consisting of a manufacturer, a retailer and a collector in which the retailer possesses private demand information and determines whether to share his private information with other chain members. Specifically, we develop four information sharing models, namely no information sharing (Model C–R), the retailer sharing information with the manufacturer (Model C–R–M), the retailer revealing information to the collector (Model C–R–C), and the retailer disclosing information to both the manufacturer and the collector (Model C–R–T). We adopt the Stackelberg game to acquire the equilibrium strategies and examine the value of information sharing on chain members’ decisions. We find that, chain members will set the largest wholesale price, retail prices of direct and indirect channels when the retailer only shares information with the manufacturer and the highest return rate can be obtained in the case of the retailer only revealing information to the collector. We can also find that, information sharing is profitable to the manufacturer and the collector, while is detrimental to the retailer. The manufacturer, the collector and the retailer can reach the largest profits in Model C–R–T, Model C–R–C and Model C–R–M, respectively.
Erkrankungen der Orbita – vom Zufallsbefund bis zum Exophthalmus
Authors: Langner Sönke , Streckenbach Felix
Published: June 2021

Orbitale Erkrankungen manifestieren sich mit einer Vielzahl an Symptomen oder sind Zufallsbefunde im Rahmen der Kopf-Hals-Bildgebung. Die Bildgebung ist entscheidend, um die Befunde differenzialdiagnostisch einordnen und die Therapie planen zu können. Diese Übersichtsarbeit stellt häufige Erkrankungen der Orbita im Erwachsenenalter, ihre typischen Bildbefunde und wichtige Differenzialdiagnosen vor.
Perceptions of the Health Care Workers about the Guideline Implemented for Safe Surgical Practice during COVID-19 Pandemic in a University Teaching Hospital
Authors: Iyer Subramania , Subramaniam Sobha , Thankappan Krishnakumar , Rao Nageswara , Satyapalan Dipu , Ravikumar Beena , Vasudevan Anu
Published: June 2021

One area of health care delivery that has been affected badly in most of the institutions is the running of the surgical services. This is due to various factors such as the presence of asymptomatic carrier stage, increased morbidity and mortality in surgical procedures in a COVID-19 patient, and possible transmission of disease to the health care workers (HCWs). A guideline was formulated in our institution, which is a tertiary care university teaching hospital to resume the surgical activities in full. Following its implementation, a questionnaire-based study was conducted to understand the perception of the HCWs about the guidelines. The questionnaire had four domains with questions related to the impact of the epidemic on the practices, composition of the guidelines, its implementation, and effects. There were 217 responders which included doctors and the supportive staff. Majority of the responders welcomed the introduction of the guidelines, and felt that it ensured patient's safety and helped streamline the services. Quarantine and preoperative reverse transcription polymerase chain reaction testing were found to be appropriate measures by the respondents. In some areas, there was a difference in the responses from the doctors to that from the supportive group which assumed statistical significance. These included the reason for drop in patient numbers was the reduced patient accessibility which was felt mainly by the doctors. The doctors perceived a delay in carrying out the work, increased workload, and mental agony due to the presence of the guidelines.
Clinical Efficacy of Medicinal Leech Therapy in Treating Third- and Fourth-Degree Hemorrhoids
Authors: Mobeen Abdul , Ahmad Ashfaque , Quamri Mohd Aleemuddin , Ansari Abdul Nasir
Published: June 2021

Objectives Hemorrhoids are characterized by bleeding, mucous discharge, itching, pain, and prolapse. This condition is known as bawaseer in Unani medicine, and Hirudinaria granulosa has been used for its treatment in Irsal-e Alaq, or medicinal leech therapy (MLT), for centuries. Hirudinaria granulosa with antithrombotic and antiinflammatory action is used in the treatment of chronic venous disease and hemorrhoids. The present study was aimed to investigate the efficacy of MLT in third and fourth-degree hemorrhoids.

Methods A single-centre prospective, clinical trial with a pre and postanalysis design was conducted at the hospital of the National Institute of Unani Medicine. Twenty male and female patients, with a mean age of 38 years, presenting moderate symptoms assessed with the colorectal evaluation of clinical therapeutics scale (CORECTS) questionnaire were included in the study. Hirudinaria granulosa were applied around the pile mass for 15 minutes weekly, for 4 weeks. The efficacy of the treatment was measured by an objective and subjective assessment using the CORECTS.

Results When analyzed by the clinician, MLT reduced the symptoms' severity score in the following domains: pain (55% improvement; p < 0.001); anorectal itching (30% improvement; p < 0.10); and bleeding (10% improvement; p < 0.7963). Significant improvement (p < 0.001) was reported in the CORECTS score in relation to pain (44.09% improvement; p < 0.001), itching (38.55% improvement; p < 0.001), swelling (44% improvement; p < 0.001), bleeding (17.28% improvement; p < 0.007), discomfort (34.01% improvement; p < 0.001), and wellbeing (32.35 %improvement; p < 0.001), giving an average overall opinion on the therapy of 4/10.

Conclusion The results of the study albeit smaller in sample size show that MLT is an effective and safe therapeutic option in reducing the symptoms of 3rd and 4th degree haemorrhoids.
Candidates rather than context shape campaign sentiment in French Presidential Elections (1965–2017)
Authors: Haselmayer Martin
Published: June 2021

The manuscript explores whether and how the strategic context of elections and candidate attributes affect campaign sentiment. Studying five decades of French presidential elections, it provides the first longitudinal test of campaign tone outside the USA. Thereby, the paper examines concerns of an increase in negativity due to changes in electoral competition. It takes leverage from the electoral system, to study whether the strategic environment of elections (first vs. second rounds of elections) or candidate characteristics (ideology and outsider status) determine the use of positive and negative tone. To this end, the paper applies sentiment analysis to personal manifestos (professions de foi) issued by all candidates running in presidential elections (1965–2017) and validates the French Lexicoder Sentiment Dictionary for longitudinal studies of campaign tone. Results reject worries about an increase in negativity in French elections over time. Moreover, while context matters to some extent, candidate attributes are by far more important for explaining campaign sentiment in presidential races. The findings contribute to research on the role of sentiment in electoral competition and tackle broader issues related to the impact of positive and negative political communication for elections and democracies.
The SπRIT time projection chamber
Authors: Barney J. , Estee J. , Lynch W. G. , Isobe T. , Jhang G. , Kurata-Nishimura M. , McIntosh A. B. , Murakami T. , Shane R. , Tangwancharoen S. , Tsang M. B. , Cerizza G. , Kaneko M. , Lee J. W. , Tsang C. Y. , Wang R. , Anderson C. , Baba H. , Chajecki Z. , Famiano M. , Hodges-Showalter R. , Hong B. , Kobayashi T. , Lasko P. , Łukasik J. , Nakatsuka N. , Olsen R. , Otsu H. , Pawłowski P. , Pelczar K. , Sakurai H. , Santamaria C. , Setiawan H. , Taketani A. , Winkelbauer J. R. , Xiao Z. , Yennello S. J. , Yurkon J. , Zhang Y.
Published: June 2021

The Superconducting Analyzer for MUlti-particles from RAdioIsotope (SAMURAI) Pion-Reconstruction and Ion-Tracker Time Projection Chamber (SπRIT TPC) was designed to enable measurements of heavy ion collisions with the SAMURAI spectrometer at the RIKEN radioactive isotope beam factory and provides constraints on the equation of state of neutron-rich nuclear matter. The SπRIT TPC has a 50.5 cm drift length and an 86.4 × 134.4 cm2 pad plane with 12 096 pads that are equipped with the generic electronics for TPCs. The SπRIT TPC allows for an excellent reconstruction of particles and provides isotopic resolution for pions and other light charged particles across a wide range of energy losses and momenta. The details of the SπRIT TPC are presented, along with discussion of the TPC performance based on cosmic rays and charged particles emitted in heavy ion collisions.
Measurements of neutral particle energy spectrum on EAST using a time-of-flight low-energy neutral particle analyzer
Authors: Liu N. X. , Mu L. , Ding R. , Zhu Y. B. , Li S. , Xie H. , Yan R. , Peng J. , Chen J. L.
Published: June 2021

The neutral particles generated by charge exchange reactions can play an important role in erosion of first wall materials in fusion devices. In order to measure the flux and energy of neutral particles to the first wall, a low-energy neutral particle analyzer (LENPA) based on the time-of-flight method has been developed and successfully applied on the Experimental Advanced Superconducting Tokamak (EAST)' to measure the neutrals with an energy of 20–3000 eV. The LENPA works in the counting mode, and the signal of photons is used as the reference for the flight time of neutrals. The energy spectrum of low-energy neutral particles on EAST has been obtained for the first time. The new diagnostics can help in understanding the neutral particle generation and deposition on the first wall materials in tokamaks under different plasma conditions.
Persistent polyamorphism in the chiton tooth: From a new biomineral to inks for additive manufacturing
Authors: Stegbauer Linus , Smeets Paul J. M. , Free Robert , Wallace Shay G. , Hersam Mark C. , Alp Esen E. , Joester Derk
Published: June 2021

Significance

Biomineralization is a highly successful strategy to create functionally graded materials with complex shape. Herein, we demonstrate that the rock-grazing mollusk
Cryptochiton stelleri
uses two amorphous, yet structurally distinct, phases in neighboring microarchitectural domains to reinforce its dentition. Nano-disperse santabarbaraite, an amorphous iron hydroxyphosphate, is present in the stylus, extending the range over which hardness and stiffness vary by at least a factor of two. Use of ferric phosphates with low iron and high water content may present a stratagem to create strong composites with low density. Indeed, we show that bio-inspired inks based on chitosan and mineral precursors allow three-dimensional printing of tunable composites strengthened by amorphous nanoparticles precipitated in situ.
A case study of unquiet translators
Authors: Monzó-Nebot Esther
Published: June 2021

Remarkable efforts have been made in Translation and Interpreting Studies to test the subservient habitus hypothesis formulated by Simeoni (1998) in his seminal work. In the face of increasing evidence that translators tend to reproduce a given society’s or community’s prevalent norms and contribute to the stability of such norms (Toury 1978), subversive translation practices have been reported (Delabastita 2011; Woods 2012) and indeed promoted as a way of fostering social and cultural change (Levine 1991; Venuti 1992). However, insights into how translators’ subservient or subversive habitus develop and depart from each other are still lacking. In order to shed light on this gray area, this article scrutinizes the contrasts between the habitus of professional legal translators who acquiesce to and who reject the norms governing their positions in the field. Special attention is given to those who decide to abandon the translation field. Their behavior is examined by relating habitus to forms of socialization and studying the implications of their strategies. Based on a case study drawn from interview data, this article focuses on the social practices of resistance and rebellion vis-à-vis subservience, and the impact of both on translation workplaces, work processes, and translators’ futures.
Verticillium dahliae (Verticillium wilt).
Authors: Subbarao Krishna
Published: June 2021

V. dahliae affects many important crops worldwide and causes economically significant losses in many countries (Pegg and Brady, 2002; Inderbitzin and Subbarao, 2014). History shows that V. dahliae has the potential to evolve new strains that can overcome the resistance in commercial cultivars, particularly in cotton, lettuce, tomato and sunflower. It has also shown that the pathogen can be taken to new areas and cause serious losses (Nachmias and Krikun, 1985). Thus, for many vulnerable crops, selection for wilt resistance remains a major criterion of disease management.
Transforming a Two-Dimensional Layered Insulator into a Semiconductor or a Highly Conductive Metal through Transition Metal Ion Intercalation
Authors: Yan Xiu , Zhen Wei-Li , Weng Shi-Rui , Zhang Ran-Ran , Zhu Wen-Ka , Pi Li , Zhang Chang-Jin
Published: June 2021

Atomically thin two-dimensional (2D) materials are the building bricks for next-generation electronics and optoelectronics, which demand plentiful functional properties in mechanics, transport, magnetism and photoresponse. For electronic devices, not only metals and high-performance semiconductors but also insulators and dielectric materials are highly desirable. Layered structures composed of 2D materials of different properties can be delicately designed as various useful heterojunction or homojunction devices, in which the designs on the same material (namely homojunction) are of special interest because preparation techniques can be greatly simplified and atomically seamless interfaces can be achieved. We demonstrate that the insulating pristine ZnPS3, a ternary transition-metal phosphorus trichalcogenide, can be transformed into a highly conductive metal and an n-type semiconductor by intercalating Co and Cu atoms, respectively. The field-effect-transistor (FET) devices are prepared via an ultraviolet exposure lithography technique. The Co-ZnPS3 device exhibits an electrical conductivity of 8 × 104 S/m, which is comparable to the conductivity of graphene. The Cu-ZnPS3 FET reveals a current ON/OFF ratio of 105 and a mobility of 3 × 10−2 cm2⋅V−1⋅s−1. The realization of an insulator, a typical semiconductor and a metallic state in the same 2D material provides an opportunity to fabricate n-metal homojunctions and other in-plane electronic functional devices.
Common (π,π) Band Folding and Surface Reconstruction in FeAs-Based Superconductors
Authors: Cai Yongqing , Xie Tao , Yang Huan , Wu Dingsong , Huang Jianwei , Hong Wenshan , Cao Lu , Liu Chang , Li Cong , Xu Yu , Gao Qiang , Miao Taimin , Liu Guodong , Li Shiliang , Huang Li , Luo Huiqian , Xu Zuyan , Gao Hongjun , Zhao Lin , Zhou X. J.
Published: June 2021

High resolution angle-resolved photoemission spectroscopy (ARPES) measurements are carried out on CaKFe4As4, KCa2Fe4As4F2 and (Ba0.6K0.4)Fe2As2 superconductors. Clear evidence of band folding between the Brillouin zone center and corners with a (π,π) wave vector has been found from the measured Fermi surface and band structures in all the three kinds of superconductors. A dominant

2

×

2

surface reconstruction is observed on the cleaved surface of CaKFe4As4 by scanning tunneling microscopy (STM) measurements. We propose that the commonly observed

2

×

2

reconstruction in the FeAs-based superconductors provides a general scenario to understand the origin of the (π,π) band folding. Our observations provide new insights in understanding the electronic structure and superconductivity mechanism in iron-based superconductors.
Observation of two truly independent laser interference made easy
Authors: Kawalec Tomasz , Sowa Piotr
Published: June 2021

An interference of two beams coming from one laser is a well-known and popular experiment. But is it possible to obtain interference fringes using two completely independent laser sources? If the answer is ‘yes’, is such an observation available in a typical optical laboratory? We show a simple but spectacular method of observing such an interference, using very common continuous wave He–Ne lasers as well as diode lasers often found in atomic physics laboratories. The contrast of the fringes ranges from 27% to 87%, depending on the laser properties. The method works for both single and multi-mode unstabilized He–Ne lasers. The fringes are visible on a scientific as well as on a common security camera.
High-precision temperature measurement with adjustable operating range based on weak measurement
Authors: Liu Miaomiao , Li Hongjing , Wang Gongling , Xia Binke , Huang Jingzheng , Zeng Guihua
Published: June 2021

High-precision temperature measurement with adjustable operating range is investigated and experimentally demonstrated based on weak measurement in the frequency domain. The operating range of measurement is precisely modulated by introducing a dynamic extra time delay to the post-selection pumped by a femtosecond laser. By choosing appropriate nonlinear materials and the attenuation, the resolution of the optimized extra time delay can be improved by two orders of magnitude over that of a traditional phase delay compensator. Considering the influence of noise in the experiment, the highest precision of 8.03 × 10−7 °C can be achieved by using a currently available spectrometer. Moreover, the average sensitivity can reach to 38 nm/°C. Taking advantage of the high precision and adjustable operating range, the proposed method has great potential applications in high-precision temperature measurements.
Moiré superlattice modulations in single-unit-cell FeTe films grown on NbSe2 single crystals*
Authors: Deng Han-Bin , Li Yuan , Feng Zili , Guan Jian-Yu , Yu Xin , Huang Xiong , Liu Rui-Zhe , Zhu Chang-Jiang , Liu Limin , Sun Ying-Kai , Peng Xi-Liang , Li Shuai-Shuai , Du Xin , Wang Zheng , Wu Rui , Yin Jia-Xin , Shi You-Guo , Mao Han-Qing
Published: June 2021

Interface can be a fertile ground for exotic quantum states, including topological superconductivity, Majorana mode, fractal quantum Hall effect, unconventional superconductivity, Mott insulator, etc. Here we grow single-unit-cell (1UC) FeTe film on NbSe2 single crystal by molecular beam epitaxy (MBE) and investigate the film in-situ with a home-made cryogenic scanning tunneling microscopy (STM) and non-contact atomic force microscopy (AFM) combined system. We find different stripe-like superlattice modulations on grown FeTe film with different misorientation angles with respect to NbSe2 substrate. We show that these stripe-like superlattice modulations can be understood as moiré pattern forming between FeTe film and NbSe2 substrate. Our results indicate that the interface between FeTe and NbSe2 is atomically sharp. By STM–AFM combined measurement, we suggest that the moiré superlattice modulations have an electronic origin when the misorientation angle is relatively small (≤ 3°) and have structural relaxation when the misorientation angle is relatively large (≥ 10°).
TeraPulse Lx for terahertz imaging of painting on canvas
Authors: Sirro Sergei , Odlyanitskiy Evgeniy , Portieri Alessia , Taday Phil , Arnone Donald D. , Guillet Jean-Paul , Smolyanskaya Olga
Published: June 2021

The goal of this study was to detect and inspect the paint layers below the surface independently of any surface features. Using the for THz-TDS imaging system, we obtained contrast images of layers of paint applied to the back side of the canvas. The most difficult task that the researchers have set themselves has not yet been fully resolved. When we try to read the signatures through several layers of paint, background and canvas, we cannot get a clear image of the letters, but we can accurately determine the location of all the signatures.
Entanglement and violation of the discrete symmetries in oscillating systems
Authors: Simonov K. , Capolupo A. , Giampaolo S. M.
Published: June 2021

We analyse how the self-gravitational interaction of a system consisted of identical mixed particles affects the probability oscillations of any single element of the system. Such a self-gravitational interaction induces a violation of the CPT-symmetry due to the breaking of the T-symmetry and the simultaneous preservation of the CP-symmetry. The violation of the T-symmetry could be traced back to the establishment of a non-vanishing entanglement among the different particles. Being a pure many-body effect, it scales with the system’s size and, hence, could have played a key role in situations characterized by extremely high density as the first stages of the Universe or in the core of very dense systems. Next experiments based on Rydberg atoms confined in microtraps and optically manipulated could simulate the discussed effect.
Biosensing by Direct Observation of Leaky Waveguide Modes
Authors: Gupta Ruchi , Pal Anil K , Goddard Nicholas J
Published: June 2021

The resonance angles of leaky waveguides (LWs) can be observed directly as exponentially decaying interference fringes in waveguides with refractive index that is 0.001–0.01 higher than cover, and when illuminated with wedge-shaped light beam. This work for the first time shows that such LWs can be realised using hydrogels of acrylamide copolymerised with N-(3-aminopropyl)methacrylamide hydrochloride (APMA). LWs made of 4.5% (w:v) acrylamide/APMA crosslinked with poly(ethylene glycol) diacrylate (PEGDA, Mn: 700Da) were ∼59% and ∼56% porous to 100kDa and 300kDa species, which are typical molecular weights of biomolecules, and hence were selected for biosensing of immunoglobulin G (IgG) with protein A–biotin (PAB) as biomolecular recognition element. The limit of detection of the acrylamide/APMA LW for IgG was 3.69±0.37 nM, which is at least 1/100th of the dissociation constant of the PAB-IgG binding partners used in this work. Future work will investigate the application of acrylamide/APMA LW for biosensing of clinically relevant analytes.
Investigation of the Effects of Magnetic Additive Cobalt/Carboxyl functionalized Multi-walled Carbon Nanotubes for Enhancing the Machinability of Polycarbonate Composites under Magnetic Field
Authors: Ming Gao , Fai Cheung Chi , Bo Wang , Wai Yeung Wong
Published: June 2021

Polycarbonate (PC) has been widely applied in various industrial areas including biomedical, optical, and defence systems. According to the optical requirements of PC devices, a high-quality surface with better surface finish and transparency are necessary. However, due to the mechanical property of PC, poor surface finish due to tool marks generated during machining [1]. In this paper, a novel fabrication process is presented for enhancing the machineability in terms of higher ductility of PC without significant loss of transparency by mixing with cobalt/carboxyl multi-walled carbon nanotubes (Co/COOH-MWCNTs). Carboxyl worked as a bridge between Co and PC chain, under a magnetic field, Co caused the movement of PC chains, and connect better with polymer chains. Experimental investigations show that a low concentration of Co/COOH-MWCNTs can increase the ductility of PC by fibre reinforcing effects. The experimental results provide promising guidance for enhancing the machinability of PC by appropriate concentration of the additive.
Complex soliton patterns formation in a multi-wavelength Er-doped fiber laser
Authors: Salhi M. , Kemel M. , Nady A. , Semaan G. , Sanchez F.
Published: June 2021

We report on the emission of complex soliton patterns from a multi-wavelength mode-locked Er-doped fiber laser through nonlinear polarization rotation (NPR). The optical spectrum exhibits three distinct well-separated spectral peaks centred at 1567 nm, 1585 nm, and 1616 nm. It is mainly attributed to the linear losses and the nonlinear birefringence filtering inside the cavity. Each wavelength in the spectrum contributes by its own soliton dynamics to a composite-state soliton regime. This is verified by using an external optical tunable filter with 0.5 nm filter bandwidth to filter out the lasing at each wavelength. By controlling the cavity parameters, this regime still can be operated in harmonic states.
Estimation the dielectric properties of solvation shells and nano-cavities by solvatochromic shift of organic dye
Authors: Stepko A.S. , Savenko O.A. , Lebedev-Stepanov P.V.
Published: June 2021

We investigated the preferential solvation effect of pyridinium-N-phenolate betaine (organic dye) taken as a molecular probe in two binary solvents (water-BuOH and water-BuNH2) in concentration range 0-100%. The Onsager-Liptay model was used to connect the spectral solvatochromic shift in solvation shell of the dye with the dielectric permittivity of the environment around its chromophore. That makes it possible to estimate the effective dielectric constant in the microscopic region of the probe, based on the values of the experimentally measured solvatochromic shifts. It was shown that the solvation shell of the dye is significantly depleted with the second component of binary solvent in water solution. It is true both for the water-BuOH and water-BuNH2 solvents. The absolute spectral shift in case of water-BuNH2 solvent is greater than in the second case. However, the relative depletion is stronger in case of water-BuOH. The innovative potential of the method is in the development the nanoprobe devices to measure the dielectric constant of small objects and nano-regions, to control instantaneous solvent concentration into evaporating sessile droplet of binary solvent in different zones of the droplet.
Spontaneous atomic crystallization via diffractive dephasing in optical cavities
Authors: Boquete A. Costa , Baio G. , Robb G.R.M. , Oppo G.-L. , Griffin P. , Ackemann T.
Published: June 2021

The design of an experiment on the spontaneous crystallization of a laser-cooled, but thermal atomic cloud into a hexagonally structured phase is discussed. Atomic interaction is mediated by the dipole potential of an optical lattice formed spontaneously in a multi-mode degenerate cavity from single-mode longitudinal pumping. The length scale of the structure is given by the diffractive dephasing between the spontaneous sidebands and the on-axis pump. A linear stability indicates that the transition can be observed in a cavity of moderate finesse compatible with having the cavity mirrors outside the vacuum cell. A new anti-reflection coated cell has been assembled for this purpose.
XII Scientific Technical Conference On Low Temperature Plasma During The Deposition Of Functional Coatings
Authors: Kashapov N F , Luchkin A G
Published: June 2021

In the city of Kazan from November 10 to November 12, 2020 on the basis of the Kazan Federal University hosted the XII Scientific Technical Conference on Low Temperature Plasma during the Deposition of Functional Coatings.

One of the main tasks of the conference is to discuss and develop the fundamental principles of plasma deposition of functional coatings. Conference papers were presented in the following areas:

– Physics of gas discharge;

– Physical processes in low-temperature plasma when applying functional coatings;

– Thermodynamic, portable and optical properties of low-temperature plasma in coating processes;

– Interaction of plasma and high-energy ion beams with a solid;

– Combustion processes and heat and mass transfer in multiphase media;

– Dusty plasma;

– Plasma chemistry. Electrochemistry;

– Diagnostics of low-temperature plasma;

– Characteristics of coatings obtained using low-temperature plasma;

– Application of ion-plasma coatings.

Within the framework of the conference, a school for young scientists is held, lectures by leading scientists and specialists in the field of low-temperature plasma application are held.

Gas-discharge plasma is widely used in various fields of science and technology. Plasma is used in industry, medicine, ecology and is the basis of various devices and technologies, for example, it is used in the technology of applying functional coatings.

The friendly atmosphere at the XII Scientific Technical Conference on Low Temperature Plasma during the Deposition of Functional Coatings allowed it to become an excellent platform for the exchange of experience and generation of new ideas in the field of physics and the use of low-temperature plasma.

List of Organizing Committee are available in this pdf.
Study of physical and mechanical properties of steel after plasma modification of its surface
Authors: Kh Gadzhiev M , Tereshonok D V , Sargsyan M A , Ilichev M V , Son E E
Published: June 2021

On the basis of studies of the electrophysical characteristics of a low-temperature nitrogen plasma flow, a procedure for verifying the thermophysical properties and establishing regularities in the formation of the structure, phase composition, and properties of a metal when steels surface is exposed to plasma, plasma exposure modes were determined for modifying the surface of metals and alloys used in various applications, such as nuclear power plants.
Study of the cathode spot on a liquid electrolyte by using highspeed visualization and software of coloured images processing
Authors: Tazmeev B K , Tsybulevsky V V , Tazmeeva R N , Tazmeev G K
Published: June 2021

The processing of coloured images of concentration area of cathode spots, obtained as a result of high-speed visualization of gas discharge with a liquid electrolyte cathode, was performed. The polygon functions of empirical distribution for intensity code of color were constructed. A correlation was found between the radiation intensity and small-scale current pulsations.
About the conditions of volumetric combustion of the gas discharge with water-solution cathode in an extended discharge gap at atmospheric pressure
Authors: Tazmeev K K , Tazmeev G K
Published: June 2021

A gas discharge between liquid electrolyte cathode and copper anode was studied experimentally. Water solutions of sodium chloride were used as liquid electrolyte. The discharge was ignited in an open air atmosphere in the current range of 2-5 A at distances of 3-18 cm between the electrodes. The conditions for the formation of volumetric plasma column in discharge gap were revealed.
Thermodynamic combustion analysis of methane-hydrogen and methane-propane-butane mixture in a water heating installation
Authors: Nazarychev S A , Larionov V M , Malahov A O , Larionova I V
Published: June 2021

In this research considers the combustion of methane mixtures with hydrogen or propane-butane fuel as applied to water heating installation. The determination of conditions under which the considered mixtures have a stoichiometric composition, and the heat release rate is equal to the value that corresponds to the combustion of only methane. It is shown that the air consumption is equal in all cases. It has been established how it is necessary to change the fuel consumption depending on the concentration of gases in a mixture with methane in order to implement these conditions.
Acoustic oscillations of the gas with axial distribution of average temperature in the vortex combustion chamber
Authors: Malakhov A O , Larionov V M , Khalilov A R , Fadeev S A , Iovleva O V
Published: June 2021

Modern research of combustion processes affect a large number of combustion modes of gaseous fuel, but so far the effects associated with the occurrence of acoustic oscillations of the gas with a longitudinal temperature distribution have not been well considered. This article discusses the case of the occurrence of self-oscillations in a vortex combustion chamber.
Calculations of electro contact baking of steel powders
Authors: Sakhapov R L , Makhmutov M M , Sultanov V A
Published: June 2021

This paper discusses the use of electro contact baking of steel powder on a bronze bushing. Its main design parameters are: taper angle of the matrix part - α, deg.; internal diameter of the matrix - D, mm; length of the cylindrical deforming belt - L, mm. To prevent melting of the surface of the restored bronze part, a special electrode was used, which made it possible to bake metal powders onto the bronze surface without melting the part to be restored. The diameter of the crimp die is defined as the difference between the outer diameter of the sleeve before compression and the sum of the wear on the inner surface of the bronze sleeve and the allowance for machining to obtain the nominal size of the inner diameter of the sleeve.
Public-private partnership in fighting the COVID-19 global economic lockdown
Authors: Vaslavsky Yan I
Published: June 2021

The COVID-19 pandemic dealt a serious blow to national socio-economic systems, causing the deepest economic crisis since the Great Depression. Neither national economies and their states, nor national health and social welfare systems, nor private business, nor the global economy have stood the test of the coronavirus pandemic. The COVID-19 pandemic has predetermined an increase in the area of uncertainty as a new quality of post-coronavirus economic reality, in the structure of which private business plays a decisive role. In this regard, the principles of partnership between the state and private business in the production of public goods need theoretical understanding due to the new reality. Adequate institutionalization of relations between partners in implementing socially significant projects can be an important success factor in the fight against economic lockdown. The state dictate regarding the terms of partnership with private business, prevailing before COVID-19, largely explains the insignificant contribution of public-private partnerships (PPPs) to accelerating GDP growth in the countries of the world. After COVID-19, the priority of the intentions of private investors in organizing socially significant projects with the state should become the norm that will allow using PPPs to unlock the economic lockdown.