bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of PDMS Viscosity and Additive Amount of Curing Agent Solution on the Mechanical Properties of PDMS Fouling Release Coating
Authors: Yan Xiaoxiang , Li Mengyu , Zhao Mengying , Zhou Hongwei , Wang Yufeng , Ba Miao
Published: January 2022

The mechanical properties of PDMS fouling release coatings have a very important effect on actual use. The coating was designed and prepared to study the effect of viscosity of PDMS resin and additive amount of curing agent on the mechanical properties of the coating. The cross-linking index of the coating was used to analyze the mechanical properties of the coatings. The results indicate that the mechanical properties of the coating formed by the crosslinking reaction with a high viscosity of PDMS resin are better. Despite the different viscosity of PDMS resin, the coating has the best mechanical properties, when the mole ratio of PDMS to TEOS is 1: 18.24.
Simulation and experimental study on CO2 laser polishing quartz glass
Authors: Dai Ziruo , Chen Tao , Han Xiao
Published: January 2022

High quality surface can be quickly obtained by laser polishing quartz glass. With the improvement of application requirements of quartz glass, the combination of process parameters for optimizing CO2 laser polishing large area quartz glass sheet is proposed. The untreated quartz ground glass was scanned by CO2 laser. Taking the roughness as the research index value, the parameters affecting CO2 laser polishing were studied and analyzed. The transient model was established by COMSOL software to simulate the polishing process, predict the combination of polishing parameters, and obtain the temperature field change in the polishing process and the flow of quartz glass during melting. 300W continuous CO2 laser was used in the experiment. The effect of surface improvement was the best when the laser power was 300W, the scanning rate was 100~200mm/s. The micro area roughness can reach Ra=10.18nm. Then, the chemical corrosion was combined with CO2 laser polishing, and the quartz glass was corroded by hydrofluoric acid and sodium hydroxide solution, and then polished to obtain the average minimum roughness Ra=5.63nm. The research results can be put into practical industrial production, which is conducive to improving production efficiency and promote the development of laser polishing quartz glass technology.
Discussion on Surface Quality and Precision Control of Metal Materials in Machining Process
Authors: Hao Limin
Published: January 2022

Based on the analysis of the influence of the surface quality of metal materials on the use of machinery, this paper discusses the influence of raw material quality, technical level, residual stress, cold work hardening, machine tool machining error, cutting tool machining error, mechanical positioning error and mechanical adjustment error on the surface quality and machining accuracy of metal materials. By studying the measures such as strengthening the quality control of raw materials, reasonably selecting processing technology, controlling the processing process, reducing the original error and making error compensation, the aim is to optimize the machining environment and improve the processing quality of finished products.
Raw materials selection method based on the durability of the concrete for bridge
Authors: Jiang Yongxiang , Wang Yue , Ma Yaoju , Yu Lei , Wang Xueguang
Published: January 2022

To enhance the durability of the cement concrete of the bridge, C40 and C50 concretes with different raw materials have been made. A method of optimal selection method for raw materials has been put forward. For different raw materials from different plant, based on the orthogonal experimental design, certain raw materials groups are gained. By the same C40 and C50 concrete mix proportion but different raw materials groups, the specimens have been made for testing the performance of the compressive strength, carbonization and anti-chloride penetration. By range analysis, the best raw material group of the concrete with higher compressive strength, lower chloride penetration coefficient and lower carbonization depth has been selected.
Effect of Ultrasonic Rolling on Properties of GCr15 Bearing Steel
Authors: Zhang Xu , Liu Wentao , Wang Shouren , Wang Kejun , Wang Dongfeng , Liu Lei
Published: January 2022

The effects of ultrasonic rolling processing on the properties of GCr15 bearing steel were studied in this paper. The specimens were treated with different values of preload in ultrasonic rolling processing. The surface roughness, microhardness and rolling contact fatigue life of the specimens before and after ultrasonic rolling processing were analysed and compared. The index of power density was firstly introduced and combined with ultrasonic rolling parameters. The results show that the qualities of surface roughness and microhardness are improved after ultrasonic rolling treatment, and the friction coefficient is reduced. However, when the ultrasonic rolling power density exceeds 11.24 Gw/cm2, the grain sizes of the specimens becomes larger, which leads to the increase of the internal stress, resulting in the initiation and propagation of crack. The propagation mode of fatigue cracks changes from transcrystalline to intergranular after ultrasonic rolling treatment, reducing the performances of wear resistance and rolling contact fatigue.
Tube-burst Analysis of SA-213TP437H high Temperature Superheater
Authors: Tan Xiaoxia
Published: January 2022

A SA-213TP437H high temperature superheater tube burst in a power plant. In this paper, combined with it’s runtime environment, macro examination, metallographic examination, electron microscope observation and micro area composition analysis were used to analyze the failure reason of the sample tube. The results show that: Due to the fine grain size of superheater tube, a large number of σ brittle phase are precipitated in the metallographic structure in lower temperature. During long-term running, the tube was affected form low cycle fatigue cracking by temperature stress coursed by the load change of generator set, start and stop and so on., which is a long-term over temperature tube burst. Although it is an example of misuse of ultra-fine grain steel pipe, it is recommend that the power plants should conduct spot-check of grain size for other SA-213TP437H high temperature superheater tube, and eliminate similar dangers of superheater tube burst.
Effects of Raceway Convexity on Friction Moment of Tapered Roller Bearings
Authors: Liu Lei , Liu Wentao , Wang Kejun , Wang Dongfeng , Wang Yanjun , Zhang Xu
Published: January 2022

The Effects of raceway convexities on friction moment of tapered roller bearings were studied in this paper. A new theoretical model of friction torque of tapered roller bearings was established considering the roughness and convexities of inner and outer ring raceways. Friction between roller and raceways were analyzed under the condition of elastohydrodynamic lubrication. Based on the theoretical model and experiments, the changes of friction torque with respected to raceway convexities of tapered roller bearings were obtained. The results show that the friction moment decreases with the increase of raceway convexities, while the increase of raceway convexity leads to the increase of contact stress. Therefore, the convexity values should be balanced between friction torque and contact stress. The convexity values should be balanced between friction torque and contact stress. The optimum values of the bearing being measured raceway convexities should be 5 ~ 6μm under the test conditions.
Study on Sound Radiation Characteristics and Sound Insulation of Extruded Aluminium Plate
Authors: Wu Yanan , Li Li , Zhang Yunfei
Published: January 2022

The use of extruded aluminium plates in the subway car body can reduce the weight of the car body, but it will bring about the negative result of increased noise in the car. The extruded aluminium panels belong to rib-stiffened plate structure in which both local short wave deformation and whole long wave deformation coexist. Studying the vibro-acoustic characteristics of this structure helps to effectively control the noise in the car. In this paper, Acoustic model of extruded aluminium plate and equivalent plate were both built up based on the hybrid method of finite element and statistical energy analysis(FE-SEA) and the statistical energy method (SEA) respectively. According to the theory of statistical energy analysis(SEA), the equivalent modelling method of the aluminium extrusion was presented using a single plate This paper focuses on the sound radiation characteristics and sound insulation of extrude and equivalent structures. Results show that no matter what method is used, the calculation of the sound power and sound insulation of the two structures has the same trend. However, the results of the FE-SEA method can capture the natural frequency of the board and be more accurate reflect vibro-acoustic characteristics of extruded aluminium panels in the middle and low frequency. Equivalent plate can well predict the sound radiation characteristics and sound insulation in the mid and high frequency by using the SEA parameters of the aluminium extrusion.
Study on the high temperature microstructure stability of the high Al content Ni-based single crystal superalloy
Authors: Teng Junpeng , Su Yan , Zhong Yong , Luo Laizheng
Published: January 2022

The high-temperature structure stability of high Al content Ni-based single crystal superalloy was studied, the microstructure was observed, and the micro-mechanism of the thermal stability of the material was analyzed. The results show that the exposure time and exposure temperature have significant effects on the stability of the alloy’s high-temperature structure. With the increase of exposure temperature and/or exposure time, the γ’ phase in the material becomes coarser, gradually connects and grows, and the stability of the material structure is obviously reduced. Compared with standard heat-treated alloys after high temperature exposure, The absolute value of the γ’ and γ phases misfit increases significantly. With the increase of exposure time, although the absolute value of the two-phase misfit continues to increase, the increase of its absolute value gradually slows down. The long-term structural stability of the alloy under continuous exposure to high temperature environment is good.
Cause analysis on tube brust of T23 steel water-wall in a ultra-supercritical unit
Authors: Xu Yang , Chen Le , Wang Song
Published: January 2022

During the hydrostatic test of an ultra supercritical unit, the water wall burst occurred. The causes of leakage were analyzed by means of macro observation, chemical composition analysis, metallographic examination and hardness test. The results show that the formation of cracks is related to fatigue, extending from the inner wall to the outer wall, accompanied by corrosion and oxidation. Fatigue is the main cause of transverse crack formation.
Research on liquid flow behavior in deformed microfluidic channels made of PDMS material
Authors: Zhang Min , Luo Jianguo , Hu Rui , Lu Wenjie
Published: January 2022

In order to improve the application performances of current microfluidic systems, the liquid flow behavior in deformed microfluidic channels made of PDMS material is deeply researched in this study. During the flowing process, liquid pressure features in inelastic and elastic channels are tested and compared respectively, serious channel deformation in elastic PDMS channels is found, and the key influencing factors are summarized and provided, including channel aspect ratio α, top membrane thickness th and channel width w, etc. This study reveals the liquid flow behavior in microfluidic systems made of PDMS material, and provides theoretical and experimental basis for further structural optimization of the systems.
Effect of Ce on Microstructure and Mechanical Properties of AZ91 Magnesium Alloy
Authors: Feng Zhengyang , Wang Enmin , Zhang Mingyu , Li Xuemeng , Su Chunjian
Published: January 2022

In this paper, gravity casting experiments were used to prepare AZ91-xCe alloys, and the effects of Ce addition on the mechanical properties and structure of the AZ91-xCe alloy were analyzed. X-ray diffractometry and metallurgical microscopy were used to characterize the phase composition and microstructure of the experimental alloy, and the strength and hardness of the alloy were tested and analyzed. Results show that the addition of a small amount of Ce generates a high melting point, thermally stable A14Ce, and reduces the porosity of the alloy. The tensile strength and yield strength of the AZ91-xCe alloy have been significantly improved under joint strengthening of multiple mechanisms of fine-grain strengthening, precipitation strengthening, and solid solution strengthening. By comparing and observing the mechanical properties and microstructures of alloys with different Ce concentrations, it was concluded that at a Ce content of 0.5%, the overall performance of the alloy is optimal. Compared to the AZ91 alloy, the tensile strength was increased by 29% and the yield strength was increased by 34%.
Reduction of thermal resistance of Ag-coated GFs/copper structure using nano-Ag paste as interconnection
Authors: Lv Zhen , Zhou Chenfei , Liu Johan , Lu Xiuzhen
Published: January 2022

Reduction of the thermal resistance between graphene films (GFs) and substrate is crucial to the application of GFs in thermal management. GFs/copper structures were prepared using nano-Ag paste as interconnection material. The effect of the thickness of nano-Ag paste on thermal resistance of GFs/copper structure was investigated. A thin layer of Ag was coated on GFs by physical vapor deposition (PVD) to further reduce thermal resistance. The thermal resistance of GFs/copper structure using Ag-coated GFs is 5.84% lower than that using raw GFs. The thermal resistance of GFs/copper structure decreases first and then increases with the increase of coating temperature and thickness of Ag layer. The minimum thermal resistance of 1.64 mm2·K·W−1 was gained for GFs/copper structure using GFs coated Ag at 300 °C for 60 min.
The influence of pre-plating on the LME phenomenon of advanced high strength steel
Authors: Bai Xue , Han Yun , Jiang Guangrui , Liu Huasai , Zhang Yongqiang
Published: January 2022

The galvanized steel plate is developed to protect the car from corrosion. During the resistance spot welding, the liquid metal embrittlement (LME) phenomenon occurs because of the lower melting temperature of zinc, then the melted Zn would get penetrating into the austenite grain boundaries which would cause the LME embrittlement. The high-temperature three-point tests at 600°C, 1 mm/min could be used as experimental simulation procedure. The pre-plating technology has been used to improve the LME resistance property of the galvanized steel. It could be found from the microstructure analysis that the pre-plating Ni technology could partly solve LME issue.
Effect of compression loading speeds on the room temperature mechanical properties of as-extruded AZ31 magnesium alloy
Authors: Chen Yu , Cao Fenghong , Deng Chi , Zhang Yong , Jiang Minggang , Xiong Zubin , Shi Fulong , Liu Ruocen , Fan Kai , Wang Feng , Li Ming , Cao Hao , Gong Yusen , Chen Ruzhi
Published: January 2022

The room temperature compression experiments of as-extruded AZ31 magnesium alloy under different loading speeds were carried out on a universal tensile testing machine. The fracture failure characteristics and mechanism of the alloy under different compression loading speeds were analyzed by scanning electron microscope (SEM) and optical microscope (OM). The results show that during the compression test, the crushed AZ31 magnesium alloy sample has a certain pier coarseness, the macro fracture of the sample is located at one third of the sample, and the macro fracture mode is 45° shear fracture with the sample axis; With the increase of loading speed, the coincidence degree of macro fracture becomes worse, and its compressive strength changes in an undulating manner. When the loading speed is 2mm/min, the compressive strength reaches the peak value of 413MPa, and the fracture morphology of the sample shows a typical flat and flat rock like ductile brittle mixed fracture. With the increase of loading speed, the proportion of brittle fracture components increases, the shape of shrinkage fracture is rock like fracture, and the fracture fluctuation is relatively slow, the dimples distributed on the fracture surface are elongated and torn, and the compression speed has no obvious effect on the fracture morphology.
Preparation of Polymer Microemulsion Flocculant and its Application in Drilling Fluid
Authors: Wang Xue , Xu Nan , Zhou Kuisan
Published: January 2022

Organic macromolecular flocculants have broad application prospects in drilling fluid systems due to their strong adsorption capacity and many other advantages. At present, polyacrylamide polymer is mostly used in drilling fluid, which is difficult to dissolve, time-consuming and laborious. In this regard, this study uses acrylamide and acrylic acid as monomers, mixes acrylic acid with potassium hydroxide, adds disodium ethylenediaminetetraacetic acid solution after adsorption and filtration, and then adds acrylamide to prepare a mixed solution, using H2O2 as the initiator, polymerization reaction in microemulsion to prepare macromolecular microemulsion flocculant. It can be quickly dissolved by adding a small amount of film release agent OP-10 during application. Through the laboratory evaluation experiment of drilling fluid, it has stronger flocculation inhibition effect on the slurry formation and drill cuttings. It has strong ability to contain drill cuttings and anti-drill cuttings pollution. It is easy to absorb water to expand and can be dispersed and collapsed. The drilling roller recovery rate is high. The field application was good when carried out in Shunbei 5-14H.
Analysis and research on fracture cause of connecting bolt of wind turbine spindle
Authors: Yun Feng , Liu Jun , Liu Chunyu , Zhao Xiaochun
Published: January 2022

On a certain day in 2018, the main shaft connecting bolt of a wind turbine in a wind farm broke and failed during operation. In order to find out the cause of fracture, the fractured spindle connecting bolt was comprehensively detected and analyzed by means of appearance state analysis, chemical element composition analysis, mechanical property detection analysis, microstructure detection and fracture micro area analysis. The results show that the main reason for the fracture of the main shaft connecting bolt is that the hydrogen penetrates into the bolt surface due to improper process control during the production process, resulting in hydrogen embrittlement in the local area of the thread root. Thus, during the operation of the fan, under the combined action of bending, shear and tensile stress, the connecting bolt of the main shaft cracks at the bottom of the first thread on the side of the self rigid rod with the most concentrated stress, and expands in the form of “herringbone” brittle fracture until the overall fracture failure. It is recommended to check the bolts in the same batch to prevent hydrogen embrittlement in the whole batch.
Methodology for optimization of preload in a bolted-flange connection based on Markov theory
Authors: Wang Yuezhen , Liu Zhifeng , Li Ying , Yang Congbin
Published: January 2022

The bolted-flange connection is one of the most popular detachable mechanical joints in mechanical flange connection. It is well known that bolted-flange joints need to be tightened to meet the assembly performance in practical engineering applications. However, the dispersion of the pre-tightening force caused by the elastic interaction between the bolts has a serious impact on the sealing and safety of the product, and therefore the optimization of bolt preload has always been a hot spot in the assembly research field. Combining mathematical theory and experimental data, this paper proposes an optimization model for uniformly distributed preload based on the Markov theory. The torque method was utilized to fasten the bolt-flange joint. The bolt pre-tightening force in the final state was collected and used as sample data. A state transition model was constructed to determine the state transition matrix. Ultimately, an iterative model of the preload was deduced, and the rationality of the model was verified through experimentation. The proposed optimization method of bolt preload can be applied to determine the initial preload of each bolt. This method improves the assembly efficiency and accuracy, which provides a theoretical approach to effectively guide the tightening work of bolted-flange connections.
Simulation calculation of temperature field of gearbox in straddle monorail train
Authors: Xue Hao , Xu Honghai
Published: January 2022

For a straddle-type monorail train gearbox, analyze the heating mechanism and heat transfer mode of each element in the gearbox, establish a heat transfer model of the gearbox, use empirical formula to calculate the heating power of each heating element, and use the flow field analysis to monitor it. Accurately calculate the convective heat transfer coefficient for the volume fraction of oil and gas in each cavity. Using the method of finite element simulation, the influence of different oil injection and large spiral bevel gear steering on the temperature field distribution of the gearbox is calculated and analyzed. The results show that when the large spiral bevel gear turns for a certain amount of time, the maximum temperature of each part of the gearbox at high oil level is higher than that at low oil level; When the amount of oil injection is constant, the temperature of each part in the reverse rotation of the large spiral bevel gear is higher than that in the forward rotation. This article provides the main reference for the prediction of the temperature field of the gearbox of the straddle monorail train and the improved design of the lubricating oil passage in the gearbox.
Mathematical modelling and simulation machining of CNC milling of double-arc spiral internal bevel gear with nutation drive
Authors: Xie Daizhi , Yao Ligang , Wang Zhenya , Li Gaosong
Published: January 2022

The machining method of double-arc spiral internal bevel gear with nutation drive-by milling cutter was proposed in this paper. The mathematical modelling of milling cutter trajectory and axial cut-off of forming milling cutter was established, the special machining tool model of bevel gear was further developed by Solidcam, the simulation machining of bevel gear was carried out. Then, the gear model obtained after simulation was compared and analyzed with the theoretical gear model, and the ideal experimental results, confirmed the CNC modelling milling method processing technology could be used to process bevel gears, the research is very important to improve the development of nutation dynamic transmission.
Research on simulating the movement track of consumers holding cigarettes by using manipulator
Authors: Wang Hao , Zhang Ying , Wang Xu , Yu Zhenhua , Zhan Jianbo , Wang Tao , Zheng Han , Yue Baoshan , Yu Tingting , Xie Jiao , Yu Jiang
Published: January 2022

Consumers’ different smoking habits and movement trajectories in the process of smoking have an important impact on cigarette combustion quality and consumption feeling. By analysing the typical action of holding a cigarette, the position, posture and spatial trajectory of the cigarette were described, and the position and posture of the end effector at the beginning and end of the smoking process were considered. The curve function connecting two endpoints can be selected according to the actual constraints. There are 6 degrees of freedom in space of cigarettes, therefore, in order to simulate the motion trajectory of consumers holding cigarettes, 6R industrial robot can realize the motion trajectory of cigarettes in space. The cigarette is clamped by the cigarette holder installed on the flange at the end of the robot, and the robot drives the cigarette holder to complete the movement track of the cigarette.
Multi-objective Green Flexible Workshop Scheduling Considering Multi-energy Consumption Factors
Authors: Gao Shang , Liu Chang , Wang Guan
Published: January 2022

In order to solve the energy consumption problem of shop floor caused by machine processing, adjustment, idling and workpiece transportation, the green flexible workshop scheduling problem was studied, and a multi-objective optimization model was established with the maximum completion time, total machine load and total energy consumption as the objectives. The double-layer coding strategy was adopted to encode processes and machines respectively to optimize the scheduling scheme, and then the adaptive hybrid crossover scheme, mutation scheme and improved elite retention strategy were adopted to improve the operation efficiency and population diversity of NSGA-II algorithm. Finally, a case study is used to verify the effectiveness of the algorithm in solving the multi-objective green flexible workshop scheduling problem, which provides a reference for enterprises to achieve green manufacturing.
Innovative Analysis and Application on Magnetograms Signal
Authors: Wang Yantong , Zhou Lingyi
Published: January 2022

This study aims to make research on magnetocardiography (magnetograms) signals. Magnetocardiogram is a non-invasive method to record and analyze the magnetic components of the electromagnetic field generated by cardiac electrical activity in the cardiac cycle. We conclude the basic characteristics of the magnetograms signal to summarize the existing magnetograms measurement principles. Then we combine the initial development process and detection means of magnetograms by discussing the signal shielding of magnetograms from two aspects of hardware and software. We compare several methods of shielding electromagnetic signals on hardware and finally obtain an excellent means to shield external signals at this stage. We also conclude the current application of magnetograms in medical treatment.
Simulation study on photon generation and collection of tower applied to NICA-MPD electromagnetic calorimeter
Authors: Peng X. , Zhu K. , Ji X. , Xiao M. , Luo F. , Huang Y. , Zhu J. , Xiao W. , Luo S. , Liu Y. , He L. , Wang X.
Published: January 2022

Shashlik tower, which is composed of absorbers and
scintillators alternately, surrounded by reflector and coupled with
Silicon Photomultiplier (SiPM) by Wavelength-Shifting (WLS) fibers,
is a significant component to measure the energy and position of
photons and electrons in Electromagnetic Calorimeter (ECal), a key
detector of the Multi Purpose Detector (MPD) at the Nuclotron-based
Ion Collider facility (NICA) in Russia. In this paper, the effect of
materials adopted for absorber, reflector and WLS fiber, the length
and curvature of fibers and the electrons incident position on
photons transmission performance of tower is simulated based on
GEANT4 software. The impact of Gaussian deviation's electron beam
energy and spread of 10% in the energy range on the energy
resolution of tower is also studied. Results show that the low
polishing degree absorber, the high polishing degree TiO_2
reflector and the type of Y-11 WLS fibers bent with a curvature
radius of greater than 11 cm can significantly improve the light
output. In addition, electrons injected along the centre of tower
can make photons position distribution in SiPM more uniform. The
generation time of photons in scintillators and time of arrival at
the SiPM both obey the Landau distribution. Finally, the energy
resolution of tower can be better than 3.8%/√(E) (GeV) for a
Gaussian deviation's electron beam with an average energy of 3 GeV
and spread of 10% in the energy range.
Thickness-dependent phase transition kinetics in lithium-intercalated MoS2
Authors: Pondick Joshua V , Yazdani Sajad , Kumar Aakash , Hynek David J , Hart James L , Wang Mengjing , Qiu Diana Y , Cha Judy J
Published: January 2022

The phase transitions of two-dimensional (2D) materials are key to the operation of many devices with applications including energy storage and low power electronics. Nanoscale confinement in the form of reduced thickness can modulate the phase transitions of 2D materials both in their thermodynamics and kinetics. Here, using in situ Raman spectroscopy we demonstrate that reducing the thickness of MoS2 below five layers slows the kinetics of the phase transition from 2H- to 1T′-MoS2 induced by the electrochemical intercalation of lithium. We observe that the growth rate of 1T′ domains is suppressed in thin MoS2 supported by SiO2, and attribute this growth suppression to increased interfacial effects as the thickness is reduced below 5 nm. The suppressed kinetics can be reversed by placing MoS2 on a 2D hexagonal boron nitride (hBN) support, which readily facilitates the release of strain induced by the phase transition. Additionally, we show that the irreversible conversion of intercalated 1T′-MoS2 into Li2S and Mo is also thickness-dependent and the stability of 1T′-MoS2 is significantly increased below five layers, requiring a much higher applied electrochemical potential to break down 1T′-MoS2 into Li2S and Mo nanoclusters.
Two-step implantation of gold into graphene
Authors: Trentino Alberto , Mizohata Kenichiro , Zagler Georg , Längle Manuel , Mustonen Kimmo , Susi Toma , Kotakoski Jani , Åhlgren E Harriet
Published: January 2022

As a one-atom thick, mechanically strong, and chemically stable material with unique electronic properties, graphene can serve as the basis for a large number of applications. One way to tailor its properties is the controlled introduction of covalently bound heteroatoms into the lattice. In this study, we demonstrate efficient implantation of individual gold atoms into graphene up to a concentration of 1.7 × 1011 atoms cm−2 via a two-step low-energy ion implantation technique that overcomes the limitation posed by momentum conservation on the mass of the implanted species. Atomic resolution scanning transmission electron microscopy imaging and electron energy-loss spectroscopy reveal gold atoms occupying double vacancy sites in the graphene lattice. The covalently bound gold atoms can sustain intense electron irradiation at 60 kV during the microscopy experiments. At best, only limited indication of plasmonic enhancement is observed. The method demonstrated here can be used to introduce a controlled concentration of gold atoms into graphene, and should also work for other heavier elements with similar electronic structure.
Microscopic origin of multiferroic order in monolayer NiI2
Authors: Fumega Adolfo O , Lado J L
Published: January 2022

The discovery of multiferroic behavior in monolayer NiI2 provides a new symmetry-broken state in van der Waals monolayers, featuring the simultaneous emergence of helimagnetic order and ferroelectric order at a critical temperature of T = 21 K. However, the microscopic origin of multiferroic order in NiI2 monolayer has not been established, and in particular, the role of non-collinear magnetism and spin–orbit coupling in this compound remains an open problem. Here we reveal the origin of the two-dimensional multiferroicity in NiI2 using first-principles electronic structure methods. We show that the helimagnetic state appears as a consequence of the long-range magnetic exchange interactions, featuring sizable magnetic moments in the iodine atoms. We demonstrate that the electronic density reconstruction accounting for the ferroelectric order emerges from the interplay of non-collinear magnetism and spin–orbit coupling. We demonstrate that the ferroelectric order is controlled by the iodine spin–orbit coupling, and leads to an associated electronically-driven distortion in the lattice. Our results establish the microscopic origin of the multiferroic behavior in monolayer NiI2, putting forward the coexistence of helical magnetic order and ligand spin–orbit coupling as driving forces for multiferroic behavior in two-dimensional materials.
Doping type influence on physical diamond properties
Authors: Itsh’ak Azoulay , Klonsky Ory , Gelbstein Yaniv , Beker Peter
Published: January 2022

Diamond exhibits outstanding properties that make it a material of interest for the semiconductors industry. The industry required a silicon alternative that enabled devices to be smaller, cooler, faster, more powerful and cleaner. Diamond exhibit a large energy band gap that needs to be doped in order to observe any significant electrical conductivity. The purpose of this work is to compare the electrical properties of intrinsic and doped diamond based materials by impedance spectroscopy, I-V measurements and thermal conductivity measurements. The results of impedance measurement of the real and imaginary parts were presented in the form of a Nyquist and dielectric permittivity curves. In order to interpret the observed response, a resistor–capacitor circuit model was used for physical mechanisms interpretation. Direct evidence for the doping influence on the diamond, was obtained by I-V measurements. We describe Raman spectroscopy based method of measuring thermal conductivity of diamond doped samples, and review results achieved by line width correlation technique.
Bismuth/bismuth oxide-incorporated reduced graphene oxide nanocomposite: synthesis, characterisation, and photocatalytic activity
Authors: Algethami Merfat
Published: January 2022

This study loaded Bi/Bi2O3 on the surface of reduced graphene oxide (rGO) to perform a two-step facile synthesis of rGO@Bi/Bi2O3 as a bismuth-based nanocomposite. First, Bi/Bi2O3 nanocomposites were synthesised via a solvothermal process using Bi(NO3)3 5H2O as the Bi3+ precursor and dimethyl sulfoxide (DMSO) as the solvent. Second, we exfoliated rGO in water to functionalise Bi/Bi2O3 with a few layers of rGO. Obtained nanocomposites were characterised with scanning electron microscopy and X-ray diffraction. We also measured the nanocomposites’ photocatalytic activity using cationic dyes, specifically methylene blue (MB) and rhodamine B (RhB). Additionally, ultraviolet-visible spectroscopy was used to determine the optical properties of rGO@Bi/Bi2O3. Photodegradation was recorded under differing durations of exposure to visible light. Reaction rates were recorded at 14.6 × 10–4 min−1 and 22.2 × 10–3 min−1 for MB and RhB, respectively, while photodegradation efficiency was logged at 17% and 81%.
Study on as-cast microstructure of Fe-15Mn-10Al-5Ni-0.8C low density duplex steel
Authors: Guo Zhihe , Hu Fengya , Wang Zhongjun , Fu Kuijun , Li Weijuan , Wang Jiaji
Published: January 2022

The microstructure of Fe-15Mn-10Al-5Ni-0.8C low density duplex steel ingots was studied by laser confocal scanning calorimetry , metallographic microscopy and scanning electron microscopy. The results indicated that: the microstructure of Fe-15Mn-10Al-5Ni-0.8C low density steel was mainly composed of coarse austenite dendrites and δ-ferrite phase in dendrite. The δ-ferrite could be completely eliminated by solution treatment. A dynamic model of austenite grain growth was established. Through analysis, it was concluded that the critical temperature for rapid austenite growth was 1250 °C. The activation energy for austenite grain growth was 365 KJ/mol as calculated by Sellars’ model.
The lack of opportunity to eat together is associated with an increased risk of weight loss among independent older adults: a prospective cohort study based on the JAGES
Authors: Kusama Taro , Kiuchi Sakura , Tani Yukako , Aida Jun , Kondo Katsunori , Osaka Ken
Published: January 2022

Objective

the present study aimed to investigate the relationship between the frequency of eating together and the risk of weight loss in older adults.

Methods

this was a three-year follow-up prospective cohort study based on a self-reported questionnaire. We used data from the Japan Gerontological Evaluation Study (JAGES) conducted in 2016 and 2019. The participants were independent older adults aged ≥65 years in Japan. We used >5% weight loss during follow-up as the outcome variable and frequency of eating together as the explanatory variable. The relative risks (RRs) and 95% confidence intervals (95% CIs) were estimated based on the Poisson regression model with a Huber–White sandwich estimator for standard errors, including possible confounders.

Results

among 56,919 participants, the mean age was 73.0 years (1SD = 5.5) at baseline, and 47.9% were male. About 15.1% (n = 8,596) of the participants experienced >5% weight loss during follow-up. The proportion of each category of the eating together frequency was 36.6% for ‘every day’, 10.3% for ‘several times a week’, 26.8% for ‘several times a month’, 20.5% for ‘several times a year’ and 5.8% for ‘seldom’. Compared to ‘every day’, only ‘several times a year (RR = 1.07, 95% CI = 1.01–1.13)’ and ‘seldom (RR = 1.17, 95% CI = 1.08–1.27)’ were significantly associated with the increased risk of >5% weight loss.

Conclusion

there is a temporal association between less frequent opportunities to eat together and the increased risk of weight loss among independent older adults.
Work Exposures and Development of Cardiovascular Diseases: A Systematic Review
Authors: Moretti Anfossi Christian , Ahumada Muñoz Magdalena , Tobar Fredes Christian , Pérez Rojas Felipe , Ross Jamie , Head Jenny , Britton Annie
Published: January 2022

Introduction

Cardiovascular diseases (CVDs) are the number one cause of death, and there is evidence that work exposures could be associated with their development. This study aimed to systematically review observational studies of adults exposed to job strain, effort–reward imbalance, long working hours, job insecurity, shift work, and occupational noise, and assess the association of those work exposures with CVDs.

Methods

The Navigation Guide framework was applied. The population were adults of working age (18–65), and cohort and case–control studies were included. The work exposures were job strain, effort–reward imbalance, long working hours, job insecurity, shift work, and occupational noise. The outcomes were cerebrovascular diseases, ischaemic heart disease, and hypertensive diseases. The selection, data extraction, risk of bias assessment, and quality assessment were carried out by two reviewers independently and disagreements were solved by a third reviewer or by consensus. The synthesis of the results was done by applying the ‘vote counting based on direction’ method, and the results were summarized in an effect direction plot. The strength of the evidence for every risk factor and CVD was defined by consensus.

Results

A total of 17 643 papers were initially identified in the literature search, but after applying the filters by title and abstract, and full text, 86 studies were finally included. From the included studies, sufficient evidence was found of the harmfulness of job strain for cerebrovascular disease and ischemic heart disease. Furthermore, there was sufficient evidence of the harmfulness of shift work for ischemic heart disease. Evidence of no relationship was found between long working hours and shift work with ischaemic heart disease and hypertensive disease, respectively. The other associations of work exposures and CVDs had limited or inadequate evidence of harmfulness.

Conclusions

In this comprehensive review, there was sufficient evidence of a harmful relationship between job strain, shift work, and CVDs. For the other work exposures, more high-quality studies are needed. In order to improve current prevention strategies for CVDs, the findings of this review imply that job strain and shift work are work exposures that constitute additional risk factors that could be approached as targets for worksite interventions.

Systematic review registration

PROSPERO CRD42020179972.
An Overview of Cleaning Agents’ Health Hazards and Occupational Injuries and Diseases Attributed to Them in Sweden
Authors: Kathare Maitreyi , Julander Anneli , Erfani Behnaz , Schenk Linda
Published: January 2022

Using data from the Swedish Products Register, hosted by the Swedish Chemicals Agency (KemI), national occupational injury and disease statistics, and call records from the Swedish Poisons Information Centre (PIC) we characterize health hazards of marketed cleaning products and recorded injuries, disease, and incidents linked to cleaning or disinfection agents. The results show that cleaning agents pose many kinds of health hazards, although corrosion and irritation hazards dominate, in particular for the eyes (54% of all included products). Few products were recognized as inhalation hazards. The nature of the health hazards is reflected in the occupational disease and injury statistics and PIC records for eyes and skin but not for the respiratory tract. Among occupational disease cases attributed to cleaning or disinfection agents, 61% concern skin and 26% the respiratory tract. Among occupational injury cases 64% concern chemical burns. However, only a small part (<0.5%) of all reported diseases and injuries were explicitly attributed to cleaning or disinfection agents. On average, there were 11 cases of disease attributed to cleaning or disinfection agents per million workers and year. For occupational injuries the corresponding number was 8. The data concern a broad range of sectors and occupations, but notable sectors were healthcare, accommodation and food service, and manufacturing. Women were more likely to suffer from disease, men and women equally likely to suffer from injury. PIC cases were evenly distributed between men and women, but the clear risk cases more frequently involved men. Occupational diseases increased many-fold in 2020 while injuries decreased, which could be due to COVID-19 changing use patterns of cleaning and disinfection agents at work. We conclude that cleaning agents pose a variety of risks to a large part of the workforce, although particular attention for preventive efforts may need to be directed to the healthcare, accommodation and food service, and manufacturing sectors.
Metabolic and RNA sequencing analysis of cauliflower curds with different types of pigmentation
Authors: Chen Daozong , Yang Yingxia , Niu Guobao , Shan Xiaozheng , Zhang Xiaoli , Jiang Hanmin , Liu Lili , Wen Zhenghua , Ge Xianhong , Zhao Qiancheng , Yao Xingwei , Sun Deling
Published: January 2022

Cauliflower (Brassica oleracea var. botrytis) is a popular vegetable worldwide due to its delicious taste, high nutritional value and anti-cancer properties. Cauliflower normally produces white curds, and natural spontaneous mutations lead to the production of orange, purple or green curds. However, some white cauliflowers show uneven purple pigmentation in their curds, which seriously affects the appearance quality and economic value of this crop. The underlying mechanism is still unclear. In this study, we performed comparative transcriptional and metabolic profiling analysis of light orange, white and purplish cauliflower curds. Metabolite analysis revealed that the pigments conferring purple colouration were delphinin and cyanin. Transcriptome analysis showed that the anthocyanin metabolism-related structural genes DFR, ANS and UGT and the transcription factor genes PAP2, TT8, GL3, EGL3 and TTG1 were upregulated in purplish versus white curds. These findings shed light on the formation of purplish curds, which could facilitate the breeding of purely white or red cauliflower.
ASPIRER: a new computational approach for identifying non-classical secreted proteins based on deep learning
Authors: Wang Xiaoyu , Li Fuyi , Xu Jing , Rong Jia , Webb Geoffrey I , Ge Zongyuan , Li Jian , Song Jiangning
Published: January 2022

Protein secretion has a pivotal role in many biological processes and is particularly important for intercellular communication, from the cytoplasm to the host or external environment. Gram-positive bacteria can secrete proteins through multiple secretion pathways. The non-classical secretion pathway has recently received increasing attention among these secretion pathways, but its exact mechanism remains unclear. Non-classical secreted proteins (NCSPs) are a class of secreted proteins lacking signal peptides and motifs. Several NCSP predictors have been proposed to identify NCSPs and most of them employed the whole amino acid sequence of NCSPs to construct the model. However, the sequence length of different proteins varies greatly. In addition, not all regions of the protein are equally important and some local regions are not relevant to the secretion. The functional regions of the protein, particularly in the N- and C-terminal regions, contain important determinants for secretion. In this study, we propose a new hybrid deep learning-based framework, referred to as ASPIRER, which improves the prediction of NCSPs from amino acid sequences. More specifically, it combines a whole sequence-based XGBoost model and an N-terminal sequence-based convolutional neural network model; 5-fold cross-validation and independent tests demonstrate that ASPIRER achieves superior performance than existing state-of-the-art approaches. The source code and curated datasets of ASPIRER are publicly available at https://github.com/yanwu20/ASPIRER/. ASPIRER is anticipated to be a useful tool for improved prediction of novel putative NCSPs from sequences information and prioritization of candidate proteins for follow-up experimental validation.
qmotif: determination of telomere content from whole-genome sequence data
Authors: Holmes Oliver , Nones Katia , Tang Yue Hang , Loffler Kelly A , Lee Michael , Patch Ann-Marie , Dagg Rebecca A , Lau Loretta M S , Leonard Conrad , Wood Scott , Xu Qinying , Pickett Hilda A , Reddel Roger R , Barbour Andrew P , Grimmond Sean M , Waddell Nicola , Pearson John V
Published: January 2022

Motivation

Changes in telomere length have been observed in cancer and can be indicative of mechanisms involved in carcinogenesis. Most methods used to estimate telomere length require laboratory analysis of DNA samples. Here, we present qmotif, a fast and easy tool that determines telomeric repeat sequences content as an estimate of telomere length directly from whole-genome sequencing.

Results

qmotif shows similar results to quantitative PCR, the standard method for high-throughput clinical telomere length quantification. qmotif output correlates strongly with the output of other tools for determining telomere sequence content, TelSeq and TelomereHunter, but can run in a fraction of the time—usually under a minute.

Availability and implementation

qmotif is implemented in Java and source code is available at https://github.com/AdamaJava/adamajava, with instructions on how to build and use the application available from https://adamajava.readthedocs.io/en/latest/.

Supplementary information

Supplementary data are available at Bioinformatics Advances online.