bluuebunny/crossref_metadata_2025 huggingface dataset:
Developing new analysis tools for near surface radio-based neutrino detectors
Authors: Anker A. , Baldi P. , Barwick S.W. , Beise J. , Besson D.Z. , Chen P. , Gaswint G. , Glaser C. , Hallgren A. , Hanson J.C. , Klein S.R. , Kleinfelder S.A. , Lahmann R. , Liu J. , Nam J. , Nelles A. , Paul M.P. , Persichilli C. , Plaisier I. , Rice-Smith R. , Tatar J. , Terveer K. , Wang S.-H. , Zhao L. ,   The ARIANNA collaboration
Published: October 2023

The ARIANNA experiment is an Askaryan radio detector designed to measure high-energy neutrino induced cascades within the Antarctic ice. Ultra-high-energy neutrinos above 1016 eV have an extremely low flux, so experimental data captured at trigger level need to be classified correctly to retain as much neutrino signal as possible. We first describe two new physics-based neutrino selection methods, or “cuts”, (the updown and dipole cut) that extend the previously published analysis to a specialized ARIANNA station with 8 antenna channels, which is double the number used in the prior analysis. For a standard trigger with a threshold signal to noise ratio at 4.4, the new cuts produce a neutrino efficiency of > 95% per station-year of operation, while rejecting 99.93% of the background (corresponding to 53 remaining experimental background events). When the new cuts are combined with a previously developed cut using neutrino waveform templates, all background is removed at no change of efficiency. In addition, the neutrino efficiency is extrapolated to 1,000 station-years of operation, obtaining 91%. This work then introduces a new selection method (the deep learning cut) to augment the identification of neutrino events by using deep learning methods and compares the efficiency to the physics-based analysis. The deep learning cut gives 99% signal efficiency per station-year of operation while rejecting 99.997% of the background (corresponding to 2 remaining experimental background events), which are subsequently removed by the waveform template cut at no significant change in efficiency. The results of the deep learning cut were verified using measured cosmic rays which shows that the simulations do not introduce artifacts with respect to experimental data. The paper demonstrates that the background rejection and signal efficiency of near surface antennas meets the requirements of a large scale future array, as considered in baseline design of the radio component of IceCube-Gen2.
Absorption spectra and enhanced Kerr nonlinearity in a four-level system
Authors: Huangfu 皇 Hao-Jie 甫浩杰 , Du 杜 Ying-Jie 英杰 , Gao 高 Ai-Hua 爱华
Published: October 2023

In a coherent system, enhanced nonlinearity can be reached via far-detuned coupling fields in the presence of Autler--Townes splitting. We explore the absorption spectra and the Kerr nonlinearity of the coherent system via the interaction between a four-level atomic system and triple fields. We obtain the absorption spectra with double, triple and even quadruple peaks which depend on both the magnitude and the difference of the coupling fields. The Kerr nonlinearity always remains reversely correlated with the absorption spectra. We find that the large coupling detunings can lead to a significant growth of the Kerr nonlinearity and the degenerate four-wave mixing. Both the Kerr nonlinearity and the four-wave mixing can be managed by adjusting the detunings of the coupling fields.
Floquet spectrum and universal dynamics of a periodically driven two-atom system
Authors: Xie 谢 Wenzhu 文柱 , Zhou 周 Zhengqiang 正强 , Li 李 Xuan 轩 , Cui 崔 Simiao 思淼 , Sun 孙 Mingyuan 明远
Published: October 2023

We investigate the Floquet spectrum and excitation properties of a two-ultracold-atom system with periodically driven interaction in a three-dimensional harmonic trap. The interaction between the atoms is changed by varying the s-wave scattering length in two ways, the cosine and the square-wave modulations. It is found that as the driving frequency increases, the Floquet spectrum exhibits two main features for both modulations, the accumulating and the spreading of the quasienergy levels, which further lead to different dynamical behaviors. The accumulation is associated with collective excitations and the persistent growth of the energy, while the spread indicates that the energy is bounded at all times. The initial scattering length, the driving frequency and amplitude can all significantly change the Floquet spectrum as well as the dynamics. However, the corresponding relation between them is valid universally. Finally, we propose a mechanism for selectively exciting the system to one specific state by using the avoided crossing of two quasienergy levels, which could guide preparation of a desired state in experiments.
Identification of deuterons at BESIII*
Authors: Wang 王 Wei 维 , Zheng 郑 Bo 波 , Qin 秦 Jia-Jia 佳佳 , Wang 王 Zhi-Yong 至勇
Published: October 2023

The identification of deuterons with momenta in the range of 0.52−0.72 GeV/c is studied with specific ionization energy loss information using a data sample collected by the BESIII detector at center-of-mass energies between 4.009 and 4.946 GeV. Clean deuteron samples are selected using time of flight information. For all data samples, the deuteron identification efficiencies are higher than 95%, with a maximum difference of

% between data and Monte Carlo simulation. This verifies the effectiveness of the deuteron identification method based on specific ionization energy loss and provides valuable information for future studies on processes involving deuterons in the final state at BESIII.
Quantum calculation of axion-photon transition in electromagnetodynamics for cavity haloscope*
Authors: Li 李 Tong 佟 , Zhang 张 Rui-Jia 瑞珈
Published: October 2023

The Witten effect implies the presence of electric charge of magnetic monople and the possible relationship between axion and dyon. The axion-dyon dynamics can be reliably built based on the quantum electromagnetodynamics (QEMD) which was developed by Schwinger and Zwanziger in the 1960's. A generic low-energy axion-photon effective field theory can also be realized in the language of “generalized symmetries” with higher-form symmetries and background gauge fields. In this work, we implement the quantum calculation of the axion-single photon transition rate inside a homogeneous electromagnetic field in terms of the new axion interaction Hamiltonian in QEMD. This quantum calculation can clearly imply the enhancement of conversion rate through resonant cavity in axion haloscope experiments. We also show the promising potentials on the cavity search of new axion-photon couplings.
Experimental evidence of magnetic flux pumping in ASDEX upgrade
Authors: Burckhart A. , Bock A. , Fischer R. , Pütterich T. , Stober J. , Günter S. , Gude A. , Hobirk J. , Hölzl M. , Igochine V. , Krebs I. , Maraschek M. , Reisner M. , Schramm R. , Zohm H. ,   the ASDEX Upgrade Team
Published: October 2023

In high-β scenarios with on-axis co-current electron cyclotron current drive, which normally lowers q
0 below unity, the absence of sawteeth suggests the involvement of an additional current redistribution mechanism beyond neoclassical current diffusion. This is supported by imaging motional Stark effect diagnostic measurements, which indicate that q
0 remains consistently around 1. This phenomenon is observed in the presence of a 1/1 mode, indicating its potential role in the current redistribution. It is shown that the mode’s ability to modify the central current and suppress sawteeth increases with plasma pressure. These findings align with a recent theoretical model, which predicts a pressure threshold for sawtooth avoidance by a 1/1 quasi-interchange mode and where this threshold increases with the strength of inward current diffusion. Moreover, the advantages of the flux pumping scenario for future machines are highlighted.
Analysis of research progress in improving the performance of silicon-based anode materials for lithium-ion batteries: a combination of nanostructured silicon and silicon-based composites
Authors: Xu Longxuan
Published: October 2023

With the development and wide-use of lithium-ion batteries, silicon, due to its high theoretical specific capacity and superior fast charging performance, is being studied intensively and extensively as a new generation of anode materials for the batteries. However, challenges of large volume expansion and poor electrical conductivity has limited the performance and commercial applications of silicon-based anode materials, which is led by pulverization of silicon particles, low initial coulombic efficiency, and unstable solid-electrolyte interphase films. To solve the issues, five main strategies have been proposed correspondingly: nanostructured silicon, silicon-based composites, new binders, new electrolyte additives, and pre-lithiation. Among them, the approaches of nanostructured silicon (0D, 1D, 2D) and silicon-based composites (silicon/carbon, silicon/metal, silicon/transition metal oxide) are practical and effective, thus being explored in depth as the focus of many researches, respectively. After summarizing and analyzing the research progress in enhancing the performance of silicon-based anode materials, it is inferred that the advantages of nanostructured silicon are complementary with those of silicon-based composite materials. Silicon-based nanocomposite materials, as the combination of nanostructured silicon and silicon-based composites, are comparatively more significant and useful than either of those. Therefore, the trend of combining the two strategies to achieve a better improvement is unstoppable.
Material basis and development prospects of nano-flexible sensors
Authors: Ren Haoliang
Published: October 2023

The combination of nanosensors and flexible sensors gives modern sensors an important adaptive capability. Nanomaterials such as nanocellulose and carbon nanotubes have been successfully used for flexible sensors. Nanocellulose can be used as a good fibrous backbone or as a thin film. The nitrocellulose skeleton can be filled with conductive substances, and if the external losses are high, self-healing materials can be added appropriately. Carbon nanotubes have excellent electrical conductivity and performance stability, but also have certain characteristics of flexible and active materials, which can effectively improve the corresponding range and response sensitivity of flexible sensors. The correct use of these materials in the process can also reduce the use of the sensor loss. In this paper, the principle of nano-flexible sensors and the analysis of current products are illustrated by examples. And by analyzing successful experiments or showing the results of current applications of nanomaterials in flexible sensors. This paper focuses on how nanomaterials can be successfully applied to flexible sensors.
Research on the fiber reinforced polymer in new construction and in strengthening of steel structures
Authors: Jiang Wending
Published: October 2023

Due to their distinct advantages, fiber-reinforced polymer (FRP) composites gained popularity during the past 200 years in civil engineering area, including high durability, corrosion resistance, light weight, high modulus strength, and high quality of corrosion resistance. These ranges of features led FRP composites find their application in mechanical, structure, civil engineering, and other industries areas. Traditional construction materials such as steel cannot feed the desirable expectation, and these high-tech materials are becoming more and more popular to replace the traditional materials. By analyzing experiments conducted by other scholars, the following essay will provide a critical review of FRP’s use in strengthening steel structures, not only for its advantages but also for its disadvantages and material properties. After the research, more experiments and theoretical research should be done to let FRP strengthen-materials be accepted and widely used in industries, as FRP materials still have some drawbacks.
Progress of nanomaterials and their application in new energy batteries
Authors: Zhao Yixiang
Published: October 2023

New energy batteries and nanotechnology are two of the key topics of current research. However, identifying the safety of lithium-ion batteries, for example, has yet to be studied. This paper explores nanoscale technology and new energy batteries. This paper describes the current classification of nanomaterials, summarizes the production methods of nanomaterials, and explains the characteristics of nanomaterials. In addition, this paper sorted out the energy storage systems of new energy batteries, anode materials, cathode materials, safety issues, and applications. Finally, the application of nanomaterials in new energy batteries is discussed. It is found that nanomaterials can be divided into nanoparticles, nanosolids, and nano-assembly systems, but can also be classified according to their chemical composition. Production methods are divided into yeast cell-based methods, physical methods, and chemical methods. The study also found that geothermal energy can be used as the energy storage method of new energy batteries, sulfurized polyacrylonitrile (SPAN) can be used as the battery anode, and monocrystalline trimethyl tetraoxide can be used as the precursor to combine with the anode. There are still technical problems with the silicon anode of lithium batteries and its safety, but the battery still has many applications. MoO3 and AgWO4 can be used as proof of the combination of nanotechnology and new energy battery technology. Researchers need to do more simulation experiments to make more breakthroughs.
A review of the possible ways to increase the energy density of Lithium-ion battery
Authors: Li Xuanming
Published: October 2023

Lithium-ion battery, benefit from its unmatched energy density, compared to other kinds of cells, currently making it dominates the field of portable electronics, electric vehicles, etc. When it comes to the application of a battery, one of the most significant parameters is the energy density. Energy density is the ratio of the total charge of a battery to its mass or volume. As we can get from the definition of energy density that a battery with higher energy density can have higher power than other batteries with the same mass or volume. Battery power is certainly one of the most intuitive helps for battery applications. By reviewing and organizing the previous papers, this paper introduces the existing main methods and technologies of cathode, anode and electrolyte for improving the energy density of lithium-ion batteries, respectively, and points out the challenges encountered at this stage, followed by an outlook on practical and feasible methods and technologies for improving the energy density of lithium-ion batteries in the future from the existing research results.
Review of heat resistant concrete
Authors: Chen Shubei
Published: October 2023

Along with the rapid development and progress of industry, special properties of concrete have their corresponding applications and requirements. The development and improvement of a variety of special concrete to meet the needs of different industries has become an inevitable trend in the concrete industry. This paper explore heat-resistant concrete in special concrete through literature review and qualitative analysis, and analyze its mechanism, composition materials, application in construction and heat treatment, and the current development of heat resistant concrete. Based on the economic and infrastructure development, heat-resistant concrete, as a kind of concrete combined with heat-resistant materials, has greatly improved the richness and professionalism of building materials. Under the influence of its own advantages, heat-resistant concrete can also effectively solve the fire-resistant and heat-resistant problems of buildings.
Research progress of laser lithography
Authors: Tian Weicheng
Published: October 2023

Lithography is one of the key technologies that restrict the development of the semiconductor industry and its important role continues to be highlighted. This paper will review laser projection lithography and laser maskless lithography based on the theoretical knowledge of laser lithography, present the advantages of laser maskless lithography, discuss the latest progress of laser lithography in application fields, explore its development prospects and trends, and provide some ideas and inspiration for the further development of human laser lithography. The result shows that laser lithography can be used in the field of material processing, and lithography is one of the key technologies to fabricate semiconductor devices. The world’s most advanced lithography machine is the EUV lithography machine of the Dutch ASML. This EUV lithography machine can be used for the production of 5nm chips, so 5nm is the most advanced chip manufacturing process that EUV lithography machine can achieve. Since lithography is a high degree of composite technology, each component plays an irreplaceable role. Therefore, if further improvements are to be made to the chip process, researchers should look at all parts of the exposure system, photoresist and process technology to make them work together in harmony.
Analysis of glass relics based on principal component analysis and k-means clustering
Authors: Tong Kehan
Published: October 2023

The Silk Road was an important channel for cultural exchanges between China and the West in ancient times, of which glass was a precious item representing early trade exchanges. In China, ancient glass is generally classified into high potassium and lead-barium categories. Using data collected and classified by archaeologists for glass relics, this paper wants to investigate the differences between the classification results based on their own chemical composition data and those given empirically, and the effect of weathering on the chemical composition of glass relics. To this end, the chemical composition was first reduced using principal component analysis for non-weathered and weathered relics respectively, and three principal components were extracted for each, with variance explained at 94.49% and 98.44% respectively. Then, the number of clusters of K-means clustering was determined to be 2 after the analysis of silhouette coefficient, and then the clustering results of non-weathered and weathered glass relics were obtained by K-means clustering. For non-weathered relics, the clusters were “class Pb” and “class Pb-K”; for weathered relics, the clusters were “class Ba” and “class Pb”. Through the above study, this paper finds that glass relics can be more carefully classified according to their own chemical composition characteristics, and weathering has a great impact on the chemical composition of glass relics.
The history and trends of semiconductor materials’ development
Authors: Song Jitao
Published: October 2023

Energy, materials and information are considered to be the three pillars of the emerging technological revolution. In terms of materials, the progress of electronic materials is particularly remarkable. A giant leap forward has been made in the development of all aspects of modern science and technology by the advent of computer, which features large scale and very large scale integrated circuits. A sequence of epoch-making semiconductor materials are constantly emerging, and rapidly become productivity and production tools, which has greatly promoted the rapid development of integrated circuit industry. The development level of semiconductor integrated circuits is one of the main indicators to measure a country’s economic strength and scientific and technological progress. However, semiconductor materials are an important cornerstone of the development of integrated circuits. With the increasing number of electronic devices in all walks of life. the value of semiconductor materials is widely recognized. This paper introduces the characteristics, classification and application of semiconductor material, briefly summarizes the history of semiconductor materials from 1950s to now, and combined with its development process, studies the key factors to promote the development of semiconductor materials: the development of semiconductor materials is performance-oriented and limited by production costs. This paper puts forward the problems faced by today’s semiconductor materials, and analyzes the current trend of diversified development of semiconductor materials. This paper can help readers quickly understand the development of semiconductor materials and the important factors affecting their development, and seek more solutions for the construction and development of the semiconductor industry.
Research on the preparation of colloidal photonic crystals and the anti-counterfeiting applications
Authors: Wang Qingxiang
Published: October 2023

Anti-counterfeiting materials based on colloidal photonic crystals (PCs) have been widely studied due to their inimitable structural color and adjustable photonic band gap (PBG). And the patterned colloidal photonic crystals have been well applied in the field of anti-counterfeiting because of their easy preparation, high performance, and functionalization. The methods for preparing patterned colloidal photonic crystals are outlined, including vertical deposition, spin coating, spraying, and inkjet printing techniques. In this paper, the applications of patterned photonic crystals in the anti-counterfeiting field and their advantages are discussed, the future development of patterned photonic crystals and the challenges they face are also prospected.
Obstruction of modern silicon semiconductor and its future development
Authors: Sheng Taoran
Published: October 2023

In the past 50 years, silicon-based semiconductors have progressed rapidly, billions of transistors have been packed into a tiny area, and computer performance has increased by leaps and bounds; everything is systematically following Moore’s Law. In recent years, however, silicon transistors research and development has stagnated to a considerably lesser amount than in the past. Due to the material’s physical property, humans are unable to prevent silicon from reaching its physical constraints in both power and chip semiconductors as a result of advances in process technology and human technological requirements. Now, scientists are attempting several solutions to this problem. In the future, scientists will find a better material to replace silicon, alter the architectures of FETs, and create a new transistor with a completely different operating principle. This paper explores these three general directions for new types of semiconductors with a literature review method and based on current research findings. This paper is a good way to summarize what humans have accomplished to date and could serve as a guide for future endeavors.
Progress on the research of all-inorganic perovskite CsPbX3
Authors: Liu Chengyu
Published: October 2023

All inorganic lead halide perovskite CsPbX3 (X = CI, Br, I) has excellent optical properties such as narrowband luminescence with high efficiency, adjustable optical band gap, large absorption cross-section and high carrier transmission rate, which pays an important role in photoelectric fields such as solar cells, photoelectric and etc. Starting from the crystal structure of perovskite, this paper firstly introduces its synthesis method and morphology control method; following by the emphasizing description on its size effect, photocatalytic properties and influencing factors of optical properties; then this study discusses the issues regarding its stability; and finally summarizes and prospects its application and future development, so as to offer some references for future studies.
Advanced process and methods of drug delivery process
Authors: Lu Peixuan
Published: October 2023

Drug delivery is defined as the approaches, methods and technologies involved in transporting a drug or biological agent to the target site in order to achieve a desired therapeutic effect. The usual purpose of drug delivery is to improve the bioavailability, duration and therapeutic effects of drugs, while to overcome the shortcomings such as the drug aggregation problem, limited solubility and poor absorption, along with potential side-effects in clinical therapeutic practices. In this article, the process of drug delivery is divided into four parts: the route of administration, the stealth technology for drugs, the targeting technology for drugs, and the triggering technology for drugs. Contents, roles and methods of all the four parts are briefly introduced. Advanced technologies of drug delivery, such as biomimetic modification and surface-charged drug carrier particles for stealth, microenvironment-sensitive ligands branched on drug carrier particles and even heavy metal compounds for targeting, and different triggering methods are concisely reviewed.
Research on the progress of building the coloured monodisperse microspheres
Authors: Li Zhe
Published: October 2023

Monodisperse microsphere is a kind of new polymer material with single particle size from micron to nanometer. Because of its outstanding properties, such as tiny particle size and huge specific surface area, it can be used as micro-separator, micro-storage, micro-reactor, micro-structural units, etc., and has been widely used in the fields of storage, life science, catalyst, pharmaceutical science and so on. In recent years, it has become a research hotspot for domestic and foreign scholars. Colored monodisperse microspheres have both the monodisperse property of microspheres and the color degree of dyes or fluorescent substances, which greatly improves the contrast of microspheres and thus increases their sensitivity in detection. In this paper, the methods of preparing monodisperse microspheres and color microspheres in various literatures currently are reviewed. Focusing on several representative techniques, the ideas, benefits, and drawbacks of many sample approaches are discussed in detail, the similarities and differences of various methods are compared, and the deficiencies in this field are analyzed, and their development prospects are discussed.
Application prospect and preparation method of nanomaterials
Authors: Sui Shanglin
Published: October 2023

Nanoparticles are atomic or molecular groups composed of a very small number of atoms or molecules. The particles have a shell structure. Nanomaterials are made up of a long-range ordered arrangement of atoms in grains and a disordered interface composition. The nanomaterial has a large number of interfaces. These unique volume effects, surface effects, and macroscopic quantum tunnelling effects enable nanomaterials to have unusual mechanical, electrical, magnetic, thermal, optical, catalysis, and superconducting properties. Such characteristics make nanomaterials have significant application value in the fields of national defense, electronics, chemical industry, metallurgy, light industry, aviation, ceramics, catalysts, medicine, etc. The development of nanomaterial technology will have a profound impact on the productivity and may solve a series of problems such as food, health, energy and environmental protection fundamentally. This article analyzes the application prospect of nanomaterial and different preparation method. At the same time, the advantages and disadvantages of preparation are shown in the article which provides a literature review for researchers to refer.
Recent advance and mechanistic aspect of phytoremediation via plant growth promoting rhizobacteria (PGPR) for cadmium and chromium remediation
Authors: Teng Zuting
Published: October 2023

In this review article, the mechanism of phytoremediation via Plant Growth Promoting Rhizobacteria (PGPR) for cadmium and chromium remediation are fully discussed including phytoextraction, phytostabilization, and phytovolatilization. In addition, the factors that affected the remediation are also listed. Moreover, to obtain the state-of-art in cadmium and chromium remediation and give their future perspectives, the typical examples in literatures for cadmium and chromium remediation by PGPR are collected and reviewed. Totally, this article includes 71 references.
Molecular dynamics simulations: chemical advances and applications
Authors: Yang Muzi
Published: October 2023

Molecular dynamics simulation has developed into a mature technique for effective understanding of structure-function relationships of macromolecules. The present simulation time is close to the chemically relevant time. The collection of information on the dynamic properties of macromolecules is rich enough to change the conventional paradigm of chemical molecular structures from the study of single structures to the analysis of conformational ensembles. Here we describe the fundamentals of molecular dynamics and the improvements in obtaining such an overall direction. The application of this technique to three main problems: allosteric regulation, docking, and structural optimization, is discussed.
Challenges and optimization of PEMFC system in vehicles
Authors: Xu Lexiao
Published: October 2023

Switching from fossil fuel energy to clean and renewable energy to minimize car emissions is becoming more and more vital and crucial in the current condition of severe environmental pollution and serious fossil fuel shortage. However, there are still several issues with current fuel cell systems that prevent their widespread use. Due to Proton Exchange Membrane Fuel Cells’ (PEMFCs) poor performance and the expensive operating costs of their catalysts, fuel cells are presently not widely accessible on the market. Fuel cells are seen as a potential method to reach the goal of zero emissions since they offer excellent benefits in terms of zero emissions and high efficiency. They do this by converting chemical energy into electrical energy using hydrogen. In this study, the three main parameters that affect the performance of PMFCs and the way in which the fuel cell converts chemical energy into electrical energy are investigated. Carbon corrosion damages PEMFCs performance because of high cathode potential during startup and shutdown. The breakdown of platinum particles employed as catalysts reduces the lifetime of PEMFCs and raises costs. The improvement of fuel cell systems is reviewed, along with methods for gas purification and catalysts produced from various cutting-edge materials including graphitized carbon. In order to address any potential environmental issues with fuel cells and seek to lower greenhouse gas emissions, this paper intends to explore better alternatives and give better remedies for PEMFC performance improvement and cost reduction.
Applications of trace element and isotope geochemistry in revealing origin and evolution of thermal spring water and ore deposit
Authors: Zhu Yuwen
Published: October 2023

Geochemistry is normally referred to as the study of Earth’s chemistry by exploring properties of materials and natural processes from deep beneath the Earth’s surface to the upper atmosphere, demonstrating the natural phenomena nowadays and discovering the history of nature. This study describes a subtopic of geochemistry: inorganic isotopes and trace elements, and discusses the application of the isotopes and trace elements in studies of geothermal spring water and ore deposit. The study of water samples in Hengjing, China was accomplished with the help of gas isotope analysis. The carbon isotope ratios and gas compositions indicate that the thermal waters are mostly sourced from meteoric and mantle sources in this area. The He isotope could evolute from mantle fluid, and CO2 is a product of the carbonate decomposition of rocks at high temperatures. The other study, conducted on the Zhaoxian ore deposit, revealed the origin and processes of formation of the different compositions of the ore. The magmatic-hydrothermal activity in this tectonically active area contributes much to the mineralization process of the ore, as shown by the analysis of trace elements of pyrite. The fluid inclusion He-Ar isotope shows that the ore was characterized by crust-mantle mixing with a little participation of meteoric water.
Tritium-Containing nuclear waste water discharge from Fukushima’s risks and concerns
Authors: Zhang Chunsen
Published: October 2023

The focus of this paper is on the problems posed by tritium in the nuclear wastewater from the Fukushima nuclear power plant. The Japanese government has decided to discharge wastewater containing tritium into Pacific Ocean. However, there are still differing opinions on the effects of tritium, and it is not possible to prove that large amounts of tritium have no effect. So the research of tritium-containing wastewater is necessary. This paper reviews and discusses what is known about the tritium-containing wastewater from Fukushima and the potential impacts of tritium. This paper argues that because of the potential effects of tritium and the fact that tritium-containing wastewater discharged into the sea will eventually spread around the world, more impact assessments of tritium, scientific management of nuclear wastewater discharged from Fukushima, and follow-up investigations should be conducted.
New Partial Least Square Third-order Latent Variable Models
Authors: Cheng Hao , Li Erqian
Published: October 2023

As a special case of higher-order model, third-order model has the abilities to reflect the relations among more different levels of indicators. More specially, third-order here means that there exist three different orders of latent variables and certain amounts of observed variables. The main challenge for third-order model lies in the estimation of unknown path and loading coefficients due to the complex structure inside. Our paper proposes a new estimation algorithm for third-order model under the framework of partial least square. On the above basis, we further develop a new partial least square third-order model with quantile regression and propose a new modified algorithm correspondingly. This kind of model can capture the relations among different variables at different quantiles. In addition, we develop another new partial least square third-order model with varying coefficients, which reflecting the dynamic relations among different latent variables and observed variables.
Design and Optimization of Slurry Conveying System for Small-sized Cutter Suction Dredger
Authors: Zhuang Haifei , Liu Mingming , Wang Hairong
Published: October 2023

Aiming at the production capacity of a newly-built small-sized dredger, the slurry conveying system is optimized. Based on the performance test of the model pump, the water performance curve of the dredge pump is obtained through similarity conversion; By comparing the resistance of the two pipe diameters, the diameters of the suction and discharge pipes on the dredger are optimized, and the resistance consumption of the slurry conveying pipeline on the dredger is reduced. The proportion of the resistance of the pipe on the dredger to the head of the dredge pump is reduced from 11.7% and 28.7% to 4.8% and 13.5% respectively at the flow of 900 m3/h and 1,200 m3/h; After optimizing the pipe diameter, the NPSHa of the device is increased, the risk of cavitation of the dredge pump is reduced, and the slurry transportation capacity of the dredger is improved; The operating points of slurry transportation with conveying distance of 500 m to 3,000 m are calculated and analyzed respectively, and the production prediction curve is obtained to meet the design capacity of the dredger. The optimization of the slurry conveying system improves the matching of the dredge pump and pipeline to the dredger, and provides equipment support for the environmental protection dredging project of rivers, lakes and reservoirs.
Design and Flow Analysis of Special-Shaped Cross-Section Flow Channel Based on Selective Laser Melting
Authors: Zhao Zhengnan , Zhai Zirong , Wang Weihao , Wu Yingna , Ou Yao , Chang Hai
Published: October 2023

Selective laser melting has the potential to be applied into hydraulic pipelines manufacturing because it can realize the forming of flow channels with arbitrary direction and curvature. Due to the stacking of layers, selective laser melting still has many limitations while processing complex flow channels. In particular, the manufacturing of overhanging structures with circular cross sections needs to use internal supports to prevent surface collapse, which is challenging to be removed. Therefore, it is necessary to optimize the flow channel with a self-supporting ability, then systematically discussing its forming quality with the influence on fluid dynamics to compromise. In this paper, a simplified multi-channel structure with 1 inlet and 4 outlets is extracted from a hydraulic valve block of an aero-engine system, and the cross-section of its branch channel is re-designed to guarantee its self-supporting ability based on additive manufacturing optimization strategy. Numerical simulation was used to analyze the influence of different shape sections on the pressure loss and mass flow rate of multi-channel structure. The results show that the pressure loss and outlet flow of the 45° rhombus + ellipse section are the closest to the circular area. According to the maximum internal deformation of the three outlets, the 65° rhombus section has the better forming quality and the non-circular section is not the worst.
Thermal Field Simulation and Thermal Capacity Influence Factor Analysis of Disc Brake Based on Thermal-structure Coupling
Authors: Chang Jinyun , Jiang Daxin , Han Chao , Wu Xiaoyi , Hu Feng
Published: October 2023

The matching and heat dissipation capacity of the brake have an important impact on the braking performance of the vehicle. During braking, most of the driving kinetic energy of the vehicle is converted into the internal energy of the brake disc through friction heat generation, resulting in a quick rise in the temperature of the brake disc, thus causing a complex thermal-solid coupling problem. This paper takes the disc brake of a certain vehicle as the analysis object, establishes the finite element model of the disc brake through hypermesh, and analyzes the distribution characteristics of the contact pressure between the friction pad and the brake disc under clamping and torsion braking behaviors. A thermal-solid coupling simulation analysis method considering the actual heat flow and heat transfer boundary of the brake disc is proposed. Compared with the temperature field of the bench test, the simulation accuracy reaches 97%. Finally, three types of brake discs with point rib, rotation rib and straight rib are designed, and the influence of brake disc thickness, shape and number of ventilation rib on the thermal capacity of brake disc is analysed. It provides guidance for the structural design of brake discs and can replace partial tests and shorten the brake disc development cycle.
Motion Behaviors of Two Ascending Bubbles in a Wide Range of Viscous Liquid
Authors: Yuan Wenxu , Lin Wenbo , Chen Shichang
Published: October 2023

Foaming devolatilization is a common phenomenon in a process of viscous solution. Bubble growth and motion behaviors depends on the flow conditions and the properties of liquid phase and that is closely related to heat and mass transfer efficiency in devolatilization process. Herein, experimental study of two ascending bubbles in a wide range of viscous fluid were conducted to achieve an understanding of the formation, coalescence and escape. As a supplement and verification, the motion behaviors rising bubbles were also investigated numerically. Results showed that the first bubble generated a tail vortex to affect the next bubble entering the region. The escape time also increased from 0.3 s to 65 s as the fluid viscosity charged from 0.05.Pa · s to 447 Pa · s, and the bubble broke and it could not formed completely with a high viscous fluid in large rate. It was expected the experimental escape time of bubble in different flow rate was in good agreement with the numerical results.
The Friction Performance Analysis of Textured Gear under Starved MHD Lubrication
Authors: Zhao Hui , Fan Shuxin , Qu Zhongwei
Published: October 2023

In this paper, the lubrication model of involute spur gear lubricated by MHD is established by considering different oil supply conditions and adding non Newtonian, thermal and surface texture. Using the multigrid method, the elastohydrodynamic numerical solutions of the meshing points, nodes, and exit points under different operating conditions during the meshing process are obtained. The results show that when the gear runs out of oil, using magnetic fluid lubrication can improve the lubrication condition. Compared to non textured gear meshing, the oil film thickness of textured gears participating in meshing is larger, which is beneficial for lubrication. The texture has the greatest impact on the node. By analyzing the influence of texture parameters at nodes, it can be seen that there is an optimal value for texture width, while a smaller depth is advantageous. It can be seen that the gear texture improves the pressure and film thickness distribution in the meshing area, which is beneficial for lubrication conditions and provides a reference for optimizing the tribological design of gears.
Use of Particle Size Distribution Model to Produce High-Flowability Cementitious Composites
Authors: Chen Jiajian , Liu Lingfei
Published: October 2023

High packing density is desired for production of high-flowability cementitious composites. To achieve dense packing, various particle size distribution models have been proposed by researchers. In present study, with the use of two supplementary cementitious materials at different scale smaller than ordinary Portland cement (OPC), an ideal particle size distribution curve according to modified Andreasen’s formula has been produced. Analysis of particle size distribution showed that blending the cement with superfine cement (SFC) and/or condensed silica fume (CSF) would make the curve closer to the ideal curve, hinting that a better packing could be achieved. Packing densities of the cementitious materials were then directly obtained through a wet packing method, and results verified that cementitious materials mix blended with SFC and/or CSF own higher packing densities.
Experimental Study on Thixotropy of Temporarily Stored Sludge
Authors: Ma Yuan , Liu Mingming , Guo Tao , Wu Tengwei
Published: October 2023

Aiming at the problems of strong viscosity and low transportation efficiency of temporary stored sludge in Laogang Shanghai, an experimental study on sludge thixotropy was carried out to study the changes of sludge viscosity with shear rate and standing time, the changes of shear stress with shear rate at different solid content, and the changes of sludge shear stress with time at constant shear rate at different solid content. On this basis, dynamic equilibrium rheological curves for different solid content were established, and numerical simulation techniques were used to form a mathematical expression of the dynamic equilibrium rheological curve for temporary storage sludge. The thixotropic index for different solid content was obtained, providing theoretical support for efficient transportation of temporary storage sludge.
Research on Gas Flow in Vertical Fissure Field of Coal Mine Goaf
Authors: Xia Debin , Lei Yun , Pei Guihong
Published: October 2023

The gas in the goaf of a coal mine is difficult to extract compared to the gas in the roadway. Studying the flow pattern of gas in the goaf fracture field is of great significance for optimizing gas extraction measures and ensuring coal mine production safety. Taking a coal mining face in Shaanxi Province, China as the research object, a mathematical model of gas flow was constructed. Through finite element numerical simulation, the pressure and velocity distribution of gas in the goaf fracture field were obtained, and the influence of vertical fracture field on gas flow was analyzed. The research results provide a theoretical basis for coal mine gas control.
Calculation of Dynamic Derivatives for High-Speed Vehicles Based on the National Numerical Windtunnel Software
Authors: Wang Xinguang , Yan Hao , He Kun , Chen Qi , Wan Zhao
Published: October 2023

Based on the NNW-HyFLOW high-speed numerical simulation software, the forced-oscillation dynamic derivatives module has been constructed using the unsteady implicit method, dual time stepping and rigid rotary grid deformation. The code has been validated by the calculation of Finner, HBS, blunt cone and OV-102 vehicle in the range of Mach number 1.85∼6.85 and angle of attack 0∼20°. Compared with the results from experiments, engineering methods and other software, all predicted dynamic derivatives have the same sign as experimental values, and the overall error is within 15%, which illustrate the effectiveness of the dynamic derivative module. Due to the difference of numerical and experimental environment and error bands of both, the numerical predictions of the damping derivatives and cross-coupling derivatives are consistent with the experimental values, which means that the proposed module has the capacity to calculate dynamic derivatives for complex engineering vehicles.
CFD-based Numerical Analysis of Amphibious Vehicle Hydrodynamics during Turning Motion
Authors: Li Zhao , Sun Xuguang , Wu Jiaxiong , Sun Xiaoce , Chen Peng
Published: October 2023

Amphibious vehicle has blunt bow and multi appendage structure, and its flow field characteristics are very complicated during maneuvering. In this paper, a simplified model of amphibious vehicle with propulsion device is established, and the thrust volume force model is introduced to consider the pumping and water jet propulsion of the water effects jet propulsion device. The technique of overlapping grid is used to deal with the six-degree-of-freedom large-scale hull motion problem, and study the turning motion of amphibious vehicle under different rudder angles. The results of numerical simulation show that the amphibious vehicle will enter a stable turning state when turning on the water surface, but the heel angle is large, the draft depth and the speed drop are significant. The state of water baffle has a significant influence on vehicle trim and roll motion. Larger vehicle pitching motion amplitude will increase the risk of overturning.
Numerical Analysis of the Temperature Rise at Fast Filling of Hydrogen Storage Cylinder Based on Fluid-Thermal-Solid Coupling
Authors: Xie Huiyu , Ou Chenxi , Chen Xinhui , Yang Gang
Published: October 2023

Taking the type III hydrogen storage cylinder of a hydrogen energy detection institution as the research object, the fluid-thermal-solid coupling calculation and analysis were carried out on ANSYS Workbench, fully considering the differences among different material layers and the inhomogeneity of temperature load distribution. The results showed that the maximum temperature of the cylinder and the maximum stress on the carbon fiber winding layer both appeared at the connection between the end head and the cylinder when the filling was finished. The thermal stress caused by temperature load is small compared to the mechanical stress caused by internal pressure. The difference between the values of mechanical stress and coupling stress is not significant, and the mechanical stress on the carbon fiber winding layer was slightly smaller than the coupling stress. Due to the large expansion coefficient of the aluminum liner, the compressive thermal stress caused by the temperature load offset a part of the mechanical stress, making the coupling stress less than the mechanical stress.