bluuebunny/crossref_metadata_2025_split huggingface dataset:
Shortened and simplified traceability chain for dimensional metrology based on self-traceable standards
Authors: Deng Xiao , Yin Zhijun , Dai Gaoliang , Xiao Guangxu , Tang Zhaohui , Shen Junyu , Zhou Tong , Xue Dongbai , Xie Yuying , He Chunling , Dun Xiong , Xie Lingyun , Cheng Xinbin , Li Tongbao 
Published: August 2024

Abstract
Nanoscale measurement is an essential task of nanomanufacturing, and measurement traceability is a fundamental aspect of nanoscale measurement. High-precision nanoscale measurement instruments (e.g. atomic force microscopes (AFM) and scanning electron microscopes (SEM)) need to be calibrated by traceable standards to ensure their accuracy and reliability. However, due to the suboptimal accuracy, uniformity, and consistency of existing standards, they need to be calibrated by metrological instruments traceable to primary length standards (e.g. physical wavelength standards) before use. This results in a long traceability chain that leads to error accumulation and significantly reduces calibration efficiency. This paper proposes a novel shortened and simplified traceability chain, where the physical wavelength standard corresponding to the 7S3 → 7P4° transition frequency of chromium atoms is materialized into self-traceable gratings using the atom lithography technology. The self-traceable gratings can then be directly applied for calibrating measurement instruments. To verify this approach, the self-traceable gratings are calibrated using a metrological AFM of the Physikalisch-Technische Bundesanstalt. Measurement results confirmed the feasibility of the approach. Particularly, our results show that the self-traceable gratings have excellent uniformity over different measurement areas and consistency over different samples, both at 0.001 nm level. Finally, the application of the self-traceable gratings for the calibrations of a commercial AFM and SEM is demonstrated. The new traceability chain significantly simplifies the calibration process, providing a more reliable and higher efficient calibration approach for advanced nanomanufacturing than that of the state-of-the-art.
Underwater image restoration method based on Walsh–Hadamard transform and attenuation coefficient estimation
Authors: Guo Jia , Zhu Yun , Wang Jianyu , Lu Tongwei , Wang Hongchao 
Published: August 2024

Abstract
Underwater images often exhibit color distortion and low contrast due to the scattering and absorption of light as it travels through water. Changes in lighting conditions further complicate the restoration and enhancement of these images. Improving the quality of underwater images is crucial for advancements in fields such as marine biology research, underwater measurement, and environmental monitoring. This paper proposes an underwater image restoration method based on the Image Formation Model (IFM), utilizing the Walsh–Hadamard transform and attenuation coefficient estimation. Traditional methods rely on dark channel prior and maximum intensity prior to estimate background light (BL) and transmission maps (TMs), often performing poorly in various underwater environments. Our method uses image blur to estimate BL and depth maps and derives three-channel attenuation coefficients using the gray-world theory to obtain a more accurate TM. Experimental results on real underwater images show that our method effectively eliminates color deviation and contrast distortion while preserving image details, significantly outperforming other IFM-based restoration techniques. Compared to the closest competing algorithms, our method achieves better UIQM and UCIQE scores.
Carbon dot-loaded Fe3O4 as photonic pigments for multilevel anti-counterfeiting
Authors: Yang Wei , Luo Site , He Yang , Wang Han , Yu Haihu 
Published: August 2024

Abstract
Amorphous arrays assembled from colloidal microspheres are a way that obtains angle-independent structural colors. In order to obtain additional properties, colloidal microspheres, which are constituent units, can be modified with other materials. Here, we utilized the silane-functionalized carbon quantum dots (SiCDs) by incorporating them into the Stöber reaction to fabricate Fe3O4@SiO2/SiCDs nanospheres with a core–shell structure. Amorphous colloidal arrays (ACAs) were constructed on commercial printing paper using Fe3O4@SiO2/SiCDs nanoparticles as structural units by a simple permeation assembly. Macroscopically, the prepared ACAs exhibit the magnetic properties of Fe3O4, while under sunlight, they display bright, angle-independent structural colors. Under ultraviolet light, the array shows significant fluorescence. This enables the presentation of multidimensional information under varying magnetic and lighting conditions. By adjusting the thickness of the outer SiO2/SiCDs composite layer, the optical properties and magnetism can be controlled easily. Moreover, due to the strong light absorption capability and high refractive index of Fe3O4, the digital patterns constructed with Fe3O4@SiO2/SiCDs nanospheres demonstrate excellent multi-level anti-counterfeiting characteristics, even under water exposure. The magnetic properties of Fe3O4@SiO2/SiCDs nanospheres, along with their distinct display characteristics under different optical environments, suggest their wide applicability in the fields of multifunctional anti-counterfeiting pigments, bioimaging, and sensing displays.
Si-implantation for low ohmic contact resistances in RF GaN HEMTs
Authors: Yazdani H , Brunner F , Thies A , Würfl H J , Hilt O 
Published: August 2024

Abstract
In this work, Si implantation and activation for lowering the ohmic contact resistance (R
c) of mm-wave GaN HEMTs has been investigated. Various combinations of annealing temperature/duration and implantation doses were tested. Dopant activation was performed using a modified procedure in an MOCVD tool, involving fast temperature ramping and annealing the samples for 8 min at 1150 °C. Thereby, ∼0.02 ± 0.01 Ω mm contact resistance was achieved on a fully doped region and ∼0.1 ± 0.02 Ω mm when only the source and drain contact region was n-type doped. For comparison, a well-established alloyed Ti/Al/Ni/Au ohmic contact scheme without implantation, was used as reference resulting in an average R
c ∼ 0.34 ± 0.12 Ω mm on the same wafer. Besides the three times lowered contact resistance the implanted contacts also showed a significantly improved on-wafer homogeneity.
Impact of aging time on the morphological, mechanical, and tribological behavior of Al-6.6Si-0.2Mg-0.2La hypoeutectic alloy
Authors: Ramalingam Vaira Vignesh , Sankar Bipin , Chinmay Mundayadan Chandroth , Jeyaprakash N , Shankar Karthik V , G P Gokul Krishna , Mahesh Sivaranjani , Harikumar Karthik , Gopalkrishnan Pranay 
Published: August 2024

Abstract
The present work aimed to examine the influence of Lanthanum (La) on the morphological, mechanical, and tribological characteristics of Al-6.6Si-0.2Mg alloy. The alloy specimens were exposed to an aging process at 180 °C for 8 h and 12 h. The morphological transformation due to La addition was analysed with an emphasis on altering primary and eutectic silicon morphology, grain refinement, and intermetallic phase distribution. The experimental investigations were carried out using scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDS) whereas the hardness and wear characteristics were analyzed by performing Vickers microhardness and pin-on-disc tests. The obtained results demonstrated that lanthanum inclusion causes significant microstructure refinement, resulting in enhancing the microhardness by up to 60%, proliferating the tensile characteristics by 70%, and aiding in improving the tribological characteristics of the Al-Si-Mg alloy. The results provide a clearer understanding of the alloy modification process and offer valuable insights for enhancing the performance of Al-Si-Mg aluminium alloys in automotive and aerospace applications.
High-yield preparation of g-C3N4 nanosheet suspension by a two-step mechanochemical technique
Authors: Zhu Xiaobin , Zhou Zhengcun , Liu Xu , Yang Yifei 
Published: August 2024

Abstract
Compared with the bulk g-C3N4, g-C3N4 nanosheets have the advantages such as larger specific surface area and more active sites, making them more promising in optoelectronic applications. However, the current methods for preparing g-C3N4 nanosheets have some disadvantages such as low yield, long exfoliation time and high energy consumption. Herein, a two-step mechanochemical method combining wet ball milling with ultrasonic-ball milling has been proposed, with a high yield of up to 31.8% for suspensible g-C3N4 nanosheets. Adding YSZ balls during the ultrasound process can effectively improve the cutting efficiency of the g-C3N4 sheets, thereby increasing the yield of the suspensible nanosheets. The stability of g-C3N4 suspensions were relatively high, and the concentration of the suspensions remained above 87% after standing 24 h. The spectra of the nanosheets obtained through the two-step process had a single emission peak of 435 nm, which was suitable for photoluminescence detection.
Preparation and research of anode materials for high performance water zinc-ion batteries
Authors: Hu Na , Zhang Tiankuo , Li Shiji , Huang Longjie , Cai Yuantao , Wu Jiayi , Su Peizheng , Han Yuxi 
Published: August 2024

Abstract
With the increasing demand for electric vehicles, intelligent electronic products, and other scientific and technological products, more and more researchers have conducted research on performance issues, cost issues, and energy storage optimization. As a promising energy storage system, aqua zn-ion batteries (AZIB) have gotten a lot of attention due to their high energy storage capacity, low cost, and environmental friendly. In addition, the use of non-flammable water-based electrolytes is very important to achieve battery safety, low cost, environmental protection, and high electrical conductivity. However, due to the dendrite growth, low efficiency, and low cycle life of zinc cathode, the development of water-based zinc-ion batteries has been seriously hindered. Based on the above research background, bismuth vanadate was prepared by hydrothermal method and modified by photo deposition as a positive electrode material. The zinc negative electrode was modified by electron beam evaporation of the aluminum protective layer. The problems of low capacity and low energy density of zinc-ion batteries, zinc corrosion, and zinc dendrite formation during charge and discharge are solved, and the reversibility of the battery is improved.
Preparation and performance of cathode materials for Protonic Ceramic Fuel Cells
Authors: Wang Guoqiang , Ren Rongzheng , Qiao Jinshuo 
Published: August 2024

Abstract
Protonic ceramic fuel cells (PCFCs) stand out as a novel energy conversion device, exhibiting unique advantages in terms of both high efficiency and environmental friendliness. However, PCFC cathodes are often underperforming due to their incapability to balance the electronic, oxygen-ionic, and protonic conductions involved in the oxygen reduction reactions. In this work, a series of BaCo0.6Fe0.4-xTixFyO3-y-δ (x=0.05, 0.1, 0.2, y=0, 0.1) perovskite oxides were prepared as a platform to demonstrate the synergy effect of cation-anion co-doping in regulating the triple conduction (electron, oxygen ion, and proton). Our experiments reveal that the co-doping of Ti4+ and F− can promotively generate an elevated level of oxygen vacancies and proton defects, thereby enhancing the transport rates of both oxygen ions and protons and thus achieving a significant improvement in electrochemical performance. Specifically, the polarization impedance of the BCFTF material is measured to be only 0.12 Ω•cm2 at 650°C, and its peak power density in a PCFC cathode reaches 0.81 W cm−2. Our work may provide an innovative method to design an excellent-performance PCFC cathode.
Study on the impact of various braiding methods on the properties of class P membrane materials
Authors: Tang Gan , Dou Junchun , Wu Xuanning , Chen Kangze 
Published: August 2024

Abstract
This paper investigates the impact of various braiding methods on the properties of class P membrane materials. Mechanical properties of four types of P membrane materials with different braiding directions and forms of the same material were analysed through uniaxial tensile tests. The meridional elastic modulus differs from the zonal elastic modulus, with the latter being approximately 1.2-1.3 times greater. Adjusting the braiding mode alters the mechanical properties of the membrane materials significantly. The weft membrane material exhibits an elastic modulus approximately 1.2 times higher than that of the warp membrane material. Fabric interlaced membrane material outperforms fabric parallel and fabric cross braided membrane materials in mechanical properties. The warp direction serves as the primary braiding direction, leading to superior comprehensive mechanical properties in practical applications for fabric-interlaced braided membrane material.
Synthesis and function studies on formaldehyde adsorption of PEI-PU copolymers
Authors: Wei Yanhong , Yu Xiaowen , Zhang Luziping , Liu Wenbo , Yong Cong , Yun Tian 
Published: August 2024

Abstract
The molecular structure of branched-chain polyethyleneimine (PEI) was determined by 13C NMR, which guided the reaction of the primary amine groups in the PEI molecule with IPA-protected MDI-PTMG monoisocyanate polyurethane prepolymer to prepare PEI copolymer-modified polyurethanes (PEI-PUs). The successful synthesis of the PEI-PUs was verified by 1H NMR tests. The results of the formaldehyde adsorption test showed that the active secondary amine groups in the PEI-PU film showed high adsorption ability of formaldehyde gas at room temperature, with an absorption up to 0.804 mmol HCOH/mmol -NH-, which has the potential to be a low-VOC functional polyurethane material.
Study on the synthesis of nanometer Nickel phosphide
Authors: Yuan Guojun , Pang Jingnan , Wu Wenting , Shao Guangrui , Ye Qian , Chen Songlin , Li Deming 
Published: August 2024

Abstract
Indeed, many dyes exhibit high water solubility and biochemical stability, making them significant water pollutants. Addressing this issue requires the development of more efficient catalysts. In recent years, Nickel phosphide has been widely used as a novel catalyst for desulfurization, Nitro compound hydrogenation, heavy metal adsorption, and dye degradation.[1-2] Compared with the traditional hydrogen catalyst, nano-Nickel phosphide has higher catalytic efficiency, more stable chemical performance, excellent corrosion resistance, and wear resistance. The electrochemical test shows that Ni12P5 has stronger hydrogen evolution activity in a crystalline state than in an amorphous state. X-ray diffraction, X-ray transmission electron microscope, and X-ray photoelectron spectroscopy (XPS) show that there are double bonds of Nickel and phosphorus in the crystals. The Ni-P has the same charged properties as the Ni-fe hydrogenase and low energy consumption in hydrogen production. In order to study the specific data of high catalytic efficiency of Nickel phosphide, Nickel phosphide was prepared by hydrothermal solvent method.
Influence of Ag on the composition and characteristics of the Cu-15 wt% Fe insitu composite material
Authors: Zeng Yanqi , Zou Jin , Huang Yapan , Xu Lin , Yu Huihui , Hu Xiaona , Lu Deping , Zhang Youliang , Hu Feifei 
Published: August 2024

Abstract
Strips of Cu-15Fe-xAg material were made using the melting casting-rolling deformation technique. Utilizing digital micro-ohmmeters, scanning electron microscopes, transmission electron microscopes, and universal testing machines, researchers examined the effects of Ag addition on the microstructures, mechanical characteristics, and electrical conductivity of Cu-15Fe alloy strips. The results show that with the increasing the amount of Ag, the dendrites of the Fe phase in the Cu-15Fe-xAg alloy as cast decrease, while the number of granular dendrites increases and the size of the granular dendrites gradually decreases. The fibers of the rich Fe phase in the rolled Cu-15Fe-xAg alloy strip become finer and more uniformly distributed. The tensile strength of the Cu-15Fe-xAg material strip could improve significantly, but the change in electrical conductivity is not significant.
Multi-modified asphalt with polyphosphoric acid/rock asphalt as additives
Authors: Sun Dandan , Gao Baoqing , Zhang Xiaoyun , Wang Yanmin 
Published: August 2024

Abstract
This research focused on the preparation of multi-modified asphalt with a composite of polyphosphoric acid (PPA) and Qingchuan rock asphalt (QRA) as modifiers. The study examined the effects of varying amounts of PPA on asphalt properties and assessed how the modifiers affected the road properties of the asphalt mixture, including water stability and high-temperature stability. Findings revealed that the optimal PPA content was 0.75%, resulting in an increase in residual stability of the modified asphalt mixture from 0.8 to 0.92 and an increase in dynamic stability (DS) from 898 times/mm to 3068 times/mm. The modified asphalt mixture blended with PPA and QRA demonstrated significant enhancements in high-temperature stability and water-damage resistance.
A Strategy to Increase the Strengthness and Toughness of Epoxy Hybrid Composites
Authors: Li Liyuan , Li Jinhui , Lv Xialei , Niu Fangfang , Sun Rong 
Published: August 2024

Abstract
Bisphenol A and its congeneric compounds are key materials in photosensitive solder mask inks to improve the toughness property. However, the cured epoxy resins often exhibit brittleness and restrict their usability in solder mask inks. A series of reinforced and toughened curing epoxy resins were prepared by incorporating core-shell rubber (CSR) and nano SiO2 into diglycidyl ether of bisphenol A (DGEBA). A comprehensive investigation was executed to analyze the influence of different contents of CSR and CSR/SiO2 on the curing process, network characteristics, and mechanical properties of epoxy resins. The experimental data deliver that the introduction of CSR/SiO2 in appropriate proportions could boost the toughness and strength of cured epoxy resin significantly, while thermal stability is also improved. Nano SiO2, with its high surface area and unique surface properties, can act as a reinforcing filler, enhancing the mechanical properties of the epoxy resin, while CSR provides both strength and toughness to the composite. The fracture surface of CSR/SiO2-modified epoxy resin also demonstrates that the CSR and SiO2 nanoparticles in the epoxy matrix could effectively block the development of cracks and produce plastic deformation around the material when the material is subjected to external forces. Therefore, the prepared high-performance CSR/SiO2-based DGEBA showed great potential in solder mask inks.
Research of microstructure and properties of resistance spot welded joints of galvanized DP steel for automobile
Authors: Guo Shulan , Wang Min 
Published: August 2024

Abstract
In this paper, the resistance spot welding of galvanized DP800 steel for Automobiles was done. The microstructure, mechanical properties and Fracture morphology characteristics of galvanized DP800 steel were studied by standard tensile tests, OM, SEM, etc. The results show that columnar crystal is formed in the melting zone of galvanized DP800 steel. The direction of growth is roughly perpendicular to the fusion line. The core area of the welding joint has Coarse Flat noodles Martensite, Ferrite, Bainite, and a small amount of residual Austenite. Two tissues exist in the thermal influence zone, namely Flat Martensite and Ferrite. The base material area is Martensite and Ferrite. When the welding process parameters of resistance spot welding are 10 KA, the welding time is 25 cyc, and the electrode pressure is 3 KN, the hardness value of the weld area reaches the maximum of 380 HV. There are both toughness and brittle fractures according to the different process parameters.
Research on influence of random vibration on closed-loop drive control of MEMS gyroscope
Authors: Xu Shikai , Liu Yuxian , Chen Ting 
Published: August 2024

Abstract
In response to the unclear impact of random vibration on the drive mode of MEMS gyroscopes, this paper analyzes the effects of vibration on the use of proportional control and PID control in self-excited oscillation close-loop drive through theoretical derivation and experimental comparison. By deducing the principles of synovial comb and self-excited oscillation closed-loop drive, the performance degradation of closed-loop drive control caused by vibration is analyzed theoretically. Data was collected by PCI-4461. The result shows that the peak-peak value of the drive mode output signal of the PID control loop under vibration is 43% of that of the proportional control loop. Compared with a proportional control loop, a PID control loop can better suppress the impact of random vibration.
Cutting mechanism study on cutting tool and leading tool of super large diameter shield
Authors: Sun Miaojun , Jiang Hao , Wang Jing , Li Xingyuan , Wang Kai , Zhang Yaming , Chen Diyang , Zhang Yue 
Published: August 2024

Abstract
The cutting tool and leading tool are the primary cutting combinations when the super large diameter shield cutter head is excavated in the soft soil stratum. The cutter size, cutting parameters, and layout relationship will affect the tunneling efficiency of the cutter head. The explicit dynamics are used to simulate the cutting tool, the leading tool, and their combination. The effects of four factors, such as stratum, tool width, cutting depth, and cutting speed, on the cutting force and cutting efficiency of the cutting tool and the leading tool are studied through orthogonal test design. The research results indicate that the main factors affecting the cutting performance of cutting tools are the cutting speed and stratum. Reasonable leading tool layouts can reduce the fluctuation range of cutting force. When the leading tool path coincides with both sides of the cutting tool path, the cutter force can be significantly reduced, and the tool life can be prolonged. The research results can provide a reference for shield cutter group modeling and the layout of the cutting tool and leading tool.
Deformation mechanisms of Gr covering on Cu under nanoindentation: A molecular dynamics simulation
Authors: Zhang Jingran , Wang Xinyu 
Published: August 2024

Abstract
Many research studies have shown that graphene can enhance the mechanical properties of copper (Cu). However, the deformation behaviors and defects evolution of Gr/Cu during indentation and the recovery ratio, surface morphology, and residual defects during retraction are rarely reported. In this research, the indentation responses and deformation mechanisms of Gr/Cu are studied during whole indentation and retraction by employing molecular dynamics simulation (MD). It comes to light that the elastic phase agrees perfectly with the Hertzian theoretical model. With the nucleation of dislocation generating, the curve deviates from the Hertzian theoretical model, which indicates that the material indentation enters the plastic stage. The loading force of the Gr/Cu system fluctuates greatly during the indentation process due to the generation and emission of dislocation loops and the interaction of stacking faults. Due to the extension of the contact area and inherent properties of graphene, the elastic recovery ratio of Gr/Cu is 18.3%, which is greatly improved. The surface pile-up effect is reduced effectively by covering graphene. The types of residual defects in the Gr/Cu system include stacking fault tetrahedral (SFT), Wing-like-dislocations, prismatic loops, stacking faults, and atomic clusters.