bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bridging Science Education: Empowering Teachers Through Astronomy Training
Authors: Sulistiyowati  , Putri Gerhana P. , Hasan Faadillah M. , Jaelani Anton T. 
Published: June 2024

Abstract
We present a short report on the Astronomy training activities targeting junior and high school science teachers in Banjar City and its neighboring districts. The training is aimed to introduce the use of Astronomy as a means of delivering and exercising science since Astronomy rarely fails to attract people’s interest. More than 30 teachers, comprising mostly science teachers in the area, joined our 3-day training program, which consists of short talks, hands-on experiments, as well as presentation and discussion. The program covers the following topics: Solar System, Motion of Celestial Bodies, Telescopes and Observation, Stars, and Galaxy-Cosmology; focusing mainly on pedagogical content knowledge using experience-based learning. By the end of the training, the participants considered Solar System and Stars as the topics with the most and the least impact/comprehension improvement for them, respectively. Nevertheless, there are only slight differences on the impact scale among the topics, all of which show a mean impact scale > 3.75 out of 5. Additionally, 75% of the participants stated the materials were helpful and beneficial for them as a teacher. This indicates that, according to the participants, the training in general was fruitful and increased their understanding on the topics delivered.
From interfacial contact to thermal transport: a molecular dynamics simulation of SiO2/epoxy resin composites
Authors: Yu Shixiang , Su Xinqing , You Chaoqun , Lu Ran , Zhao Guanghui 
Published: June 2024

Abstract
A high-frequency working environment makes the heat generated by electronic components increase rapidly. The atomic level of interfacial thermal transfer between epoxy (EP) resin and various functionalized silica (SiO2) in underfill was investigated by molecular dynamics simulation (MDS) methods. The interfacial thermal transfer mechanism was examined by calculating the interfacial binding energy, atomic density distribution, phonon vibrational power spectrum (VPS), and interfacial thermal resistance (ITR) studies. This work revealed the generalized relationship between interfacial thermal transport and SiO2/EP interface interaction, which was regulated by coupling agents and the grafting ratio in chemical modification processes. The calculation results showed that interfacial thermal resistance was strongly correlated with the calculated binding energy. The interfacial contact and phonon coupling in composites were improved when SiO2 was functionalized by 3-glycidyloxypropyltrimethoxysilane (GOTMS) and 3-aminopropyltriethoxysilane (APTES). The binding energies of the two interfaces above exceeded −350 kcal/mol and relatively low ITRs of 5.05×10−9 m2KW−1 and 5.03×10−9 m2KW−1 were observed. In addition, 12% was the optimal grafting rate for SiO2 in GOTMS-modified SiO2/EP composites, and the highest interfacial binding energy of −386.88 kcal/mol in this work was obtained.
A poly (para-terphenyl piperidine)/layered double hydroxide hybrid membrane with reduced ammonia permeability for direct ammonia fuel cell
Authors: Cao Yingjian , Hu Zijun , Guo Yu , Gui Fukang , Xiao Qiangfeng 
Published: June 2024

Abstract
Anion exchange membrane fuel cells (AEMFCs) have attracted extensive attention in recent years due to their high electrode activity, potential non-noble metal catalyst application, and low requirement for fuel purity. Anion exchange membrane (AEM) is the core component of AEMFCs, which plays the role of conducting ions, blocking fuel mixing, and providing catalyst carriers. Its performance directly affects the efficiency and service life of the fuel cell. In most cases, the conductivity of AEM is generally low, and its durability is poor, which cannot meet the requirements of practical application temporarily. In this paper, from the point of view of material nanocomposite enhancement, the organic polymer and inorganic nanomaterials with high ionic conductivity are prepared using the suspension blending method, and the various properties of AEMs are tested. Compared with the bulk material, the ionic conductivity and ammonia inhibition performance are significantly improved, among which AEM doped with 4.8% LDH has the best performance, the ionic conductivity is increased by nearly an order of magnitude, and the ammonia permeation relative content is only 14.1% of the bulk material.
Structural design and magnetic study of a 2p-4f dimer complex built from a functional nitronyl nitroxide radical
Authors: Wang Yifan , Dong Huiyang , Zhu Mei 
Published: June 2024

Abstract
A novel 2p-4f cyclic [Tb (hfac)3 (NIT-4-OMe-3PyPh)]2 complex has been obtained. The crystal structure shows that the NIT-4-OMe-3PyPh radical bridged two TbIII ions by O atoms of NO units and N atoms on pyridine rings. The variable temperature magnetic susceptibility shows that both ferromagnetic and crystal field effects exist in the complex. Alternating-current magnetic data for the Tb complex exhibits slow magnetic relaxation behavior. This complex is a typical example of molecular nanomagnetic materials.
Improved design of railway wagon underframe flipping machine
Authors: Wang Yongming , Wang Chuanjian , Zhou Qi , Sun Yongwen 
Published: June 2024

Abstract
This paper took a railway wagon underframe flipping machine of a railway company as the research object and introduced its flipping process and working principle. To solve the current problems of underframe slipping and the over-deformation of the clamping mechanism and underframe, the structure of the flipping machine was improved in design. By adding centering clamping blocks to clamp both sides of the underframe, the problem of the underframe slipping was solved. A mechanical analysis of the improved clamping mechanism was conducted, and the results showed that the thrust required by the hydraulic cylinder of the improved clamping mechanism was reduced from 200 kN to 128 kN. Finite element analysis of the clamping mechanism and underframe was conducted based on Workbench software. The results showed that the maximum deformation of the improved clamping mechanism was reduced from 4.4497 mm to 2.5395 mm, and the maximum deformation of the improved underframe was reduced from 5.8123 mm to 3.1583 mm. The above results verify that the stability of the improved flipping machine has been greatly improved, and it can better realize the clamping and flipping of the railway wagon underframe.
Research on the design and damping control of rocket maritime transportation device
Authors: Luo Liang , Liu Dong , Jiang Zhen , Cheng Dong 
Published: June 2024

Abstract
Unlike conventional land-based launch vehicles, sea-launched launch vehicles can fully utilize the additional speed of Earth’s rotation to achieve the goal of saving fuel for launch vehicles. To ensure the safety of transportation and storage of rockets before sea launch, this article studies the damping absorption and protection measures of rockets during sea transportation before launch, based on the workflow and characteristics of the sea environment of rocket sea launch. Taking the maximum allowable vibration acceleration of the rocket and the vibration spectrum of the maritime transportation platform as constraints, a technical route combining “active+passive” multi-level vibration reduction methods was adopted to conduct a scheme demonstration and simulation analysis of the vibration reduction control effect of the rocket maritime transportation device. It was able to reduce the acceleration response of the rocket in the heave direction (vertical direction) by about 79%, meeting the overall indicator requirements.
Application of TRIZ theory in optimization design of end tooling for large automotive parts
Authors: Du Hao-Yu , Liu Shang , Wu Han , Guo Xiao-Xia , Wang Peng-Fei , Zhu Yu-Hang , Wang Yu-Hao 
Published: June 2024

Abstract
In the process of automobile final assembly, auxiliary assembly end tooling is often designed on the key stations to ensure the quality and efficiency of the production line. This study applies TRIZ theory and scenario analysis methods to solve the potential fault problems in the design and development stage of end tooling products to provide more reliable and high-quality products or systems. Through Ansys Workbench, the proposed scheme is simulated and optimized to verify the feasibility of the end tooling product design. Implementing this research method will help effectively deal with the challenges faced by heavy lifting in modern industrial production and improve production efficiency and operation safety.
Performance evaluation of fused magnesia production process based on exergy-economics and environmental-economics analysis
Authors: Jiang Tianchi , Wang Xin , Zhang Weijun 
Published: June 2024

Abstract
Based on the basic theories of thermal economics and thermal engineering, a magnesia factory in Liaoning Province was chosen as a research object. Researchers construct the production flow structure of different fused magnesia processes and establish mathematical models that consider calculating exergy income, exergy cost, exergy transfer, and carbon emission. The changes in the system economy and environmental protection of different production processes are analyzed through calculation. The results show that the cleaner fused magnesia system has unique advantages in exergy economic income and carbon emission.
Optimized designing of process parameters for CP980 steel resistance spot welding based on Orthogonal Test
Authors: Tian Shuai , Feng Qiaobo , Wang Chunliang , Zhang Rui 
Published: June 2024

Abstract
Based on the orthogonal experimental design method, taking CP980 steel as the research object and the tensile sheer force of spot-welded joints as the evaluation index, the effect of different process parameters on the welding performance of resistance spot welding was studied with the extreme variance method. The results indicated that welding current had a significant effect on the shear force, followed by electrode pressure, while welding time had the least effect; the optimal welding parameter of the CP980 spot welded joint was that the welding time was 400 ms, the welding current was 9.5 kA, and the electrode pressure was 3.6 kN. The formation of lath martensite during solidification led to a higher hardness in the nugget region, reaching a maximum of 434 HV. The subcritical heat-affected zone formed a softened zone with an average hardness value of 299 HV as a result of welding thermal cycling.
IGBT power module based on pressureless nano-silver sintering optimization process and its performance characterization
Authors: Wu Sheng , Xu Fan , Zhang Ru , Jiang Weibin , Jiang Nian , Hu Zechen , Zhang Zhiyang 
Published: June 2024

Abstract
In this paper, a nano-silver solder paste with a large intrinsic driving force was selected for pressureless sintering. The pressureless sintering process determined by simulated shear experiments was optimized according to the TGA results of this silver solder paste. Based on the optimized process, we realized the void-free and low-porosity sintering of large-area IGBT chips. At the same time, we used this process to fabricate complete silver sintered IGBT power modules. The silver sintered modules were characterized by static, dynamic, and thermal resistance levels, and their performance was compared with that of reflow soldered modules of the same power level. The final results indicate that the optimized process can solve the problem of voids and pore growth generated when the process determined by simulation shear experiments is directly applied to real chip sintering. The module using this process has excellent electrical performance, and the thermal resistance is reduced by 11.06% compared to the reflow soldered module, which guarantees its long-term stable operation in high-power power conversion systems.
Lightweight simulation design of integrated die-casting body rear wheel cover and seat crossbeam
Authors: Zhang Nan , Deng Guohui , Liu Guojun , Du Wencan , Zhang Yunfeng , Sun Gang , Ma Pinkui 
Published: June 2024

Abstract
This paper is based on the integrated die-casting process for the lightweight development problem of the rear wheel cover assembly and seat beam in certain vehicles. It uses heat-treat-free materials to develop and design the integrated structure of the rear wheel cover and seat beam. The manufacturability of the part is verified by mold flow analysis and a study of the impact of integrated die-casting parts on the stiffness of the entire vehicle. The simulation results show that this scheme can meet the requirements of parts manufacturability and achieve a weight reduction of 2.7 kg for the welding area, compared with the traditional steel structure, and the body stiffness is better. Comfort stiffness increased by about 6%.
Design scheme research on key technologies of portable and efficient grinding equipment for high dose stop valves in the primary circuit of nuclear power plants
Authors: Wang Yongxing , Wei Hongyu , Sun Hexing , Tao Meng , Chen Song , Luo Zhiyuan 
Published: June 2024

Abstract
In the high-dose radiation environment of the primary circuit of nuclear power plants, there are problems such as low grinding efficiency and low automation level in the grinding and repair process of the sealing surface of the stop valve seat. Using the working principle of grinding repair and manual grinding technology experience, we extracted the key process parameters for automation control. We researched the design scheme of key technologies for automated grinding equipment. In addition, we provided a detailed description of the equipment’s performance, purpose, structure, and function.
Research on quality inspection and process optimization of ship surface shot blasting and sand blasting treatment
Authors: Li Min , Huang Jiyuan , Li Songhao , Peng Moxuan , Yan Zhihong , Song Qiheng 
Published: June 2024

Abstract
The process of shot blasting and sandblasting is a crucial step before the coating of ship surfaces, as the quality of this treatment affects the adhesion and service life of the applied paint. In this paper, we have developed a machine vision inspection system for evaluating the quality of shot blasting and sandblasting on ship surfaces, enabling the acquisition of 3D microscopic surface topography under real operating conditions. Based on this, we have investigated the relationship between surface preparation techniques and the quality of the treatment, as well as the correlation between surface preparation quality and coating performance. Furthermore, we have established corresponding models to facilitate the control of shot blasting and sandblasting quality and optimize the associated processes.
Analysis of pressure loss and transmission loss under flow field effects in multi-chamber muffler
Authors: Wo Jinjin , Hu Haigang , Chen Yuehua , Liu Yifan , Linghu Shixun 
Published: June 2024

Abstract
In order to achieve broadband sound attenuation, a muffler utilizes multiple internal impedance structures, which unavoidably impacts its aerodynamic performance. Multi-chamber muffler configurations, incorporating interconnecting tubes, perforated plates, and other sound-absorbing elements, can generate several resonance peaks within the frequency range of sound attenuation, showcasing effective sound attenuation capabilities. These configurations are commonly employed in marine muffler structures. This paper examines the factors influencing the flow field performance of such mufflers and the impact of the internal flow field on their acoustic performance by using principles of fluid mechanics and the finite element method of acoustics. Initially, a flow field domain model of the multi-chamber muffler is developed by using the 3D modeling software SOLIDWORKS, and the mesh division of the flow field is executed by using the FLUENT MESHING preprocessing software. Subsequently, the mesh model is employed to simulate the flow field performance in the ANSYS Fluent environment, calculating the pressure loss of various structural mufflers under different inlet flow boundary conditions. Finally, field data is imported into the LMS Virtual. Lab software to validate the correlation between the flow field network and the acoustic field network, enabling the mapping of flow field data to simulate the silencer’s acoustic performance under different flow field conditions. The study demonstrates that a well-designed arrangement of interconnected pipes and perforated elements inside the silencer can notably diminish its pressure loss. Furthermore, it highlights that the impact of a temperature gradient on the silencer’s acoustic performance is more significant compared to the local flow rate.
Laboratory experimental study on evaluation of plugging effect
Authors: Bai Wenlong , Wang Suling , Dong Kangxing 
Published: June 2024

Abstract
Aiming at the research of water-controlled fracturing and stimulation technology of high water content Wells in Chaoyanggou low-permeability oilfield, several laboratory experiments of plugging agents are carried out. The traditional plugging agent displacement experiments mostly adopt the way of filling sand tubes, but the filling sand tube is extremely difficult to clean after the curing of the Plugging Agent And takes a long time, which is not conducive to the simulation of multi-group experiments. Therefore, a new artificial core method is used to simulate the reservoir under two permeability conditions, and the performance of three kinds of plugging agents is studied from several aspects, such as plugging performance, breakthrough pressure, and distribution law of plugging agents after injection into the core. The experimental results show that Plugging Agent A (particle class) is suitable for plugging large pores, the plugging strength is high, and the breakthrough pressure gradient is more than 9 MPa/m. Plugging Agent B (gel class) is suitable for plugging small voids, and has good plugging performance, with a plugging rate of up to 99%. The pore structure characteristics of the core after plugging are determined by SEM experiments.
Detecting climate milestones on the path to climate stabilization
Authors: MacDougall Andrew H , Rogelj Joeri , Jones Chris D , Liddicoat Spencer K , Grassi Giacomo 
Published: June 2024

Abstract
The era of anthropogenic climate change can be described by defined climate milestones. These milestones mark changes in the historic trajectory of change, and include peak greenhouse gas emissions, peak greenhouse gas concentration, deceleration of warming, net-zero emissions, and a transition to global cooling. However, given internal variability in the Earth system and measurement uncertainty, definitively saying that a milestone has passed requires rigour. Here CMIP6 simulations of peak-and-decline scenarios are used to examine the time needed to robustly detect three climate milestones: (1) the slowdown of global warming; (2) the end of global surface temperature increase; and (3) peak concentration of CO2. It is estimated that it will take 40 to 60 years after a simulated slowdown in warming rate, to robustly detect (

>

95
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change) the signal in the global average temperature record. Detecting when warming has stopped will also be difficult and it takes until the mid 22nd century to have enough data to conclude warming has stopped. Detecting that CO2 concentration has peaked is far easier and a drop in CO2 concentration of 3 ppm is consistent with a greater than 99% chance that CO2 has peaked in all scenarios examined. Thus it is likely that as the rate of CO2 emissions is reduced, and net-zero emissions is approached, interpreting the global temperature record will become difficult—with a high potential to create confusion amongst policy makers and the general public.
Using policy scenarios to assess challenges and opportunities for reaching restoration targets in Brazil’s Atlantic Forest
Authors: Shennan-Farpón Yara , Soterroni Aline C , Scarabello Marluce , Visconti Piero 
Published: June 2024

Abstract
Brazil’s Atlantic Forest is a global restoration hotspot. Most of the remaining forest areas are degraded and separated by large cities, and agricultural lands essential for national food security. Brazil’s restoration agenda is defined by multiple national and global restoration targets and policies, including Brazil’s Native Vegetation Protection Law (No. 12,651/2012) also known as the Forest Code, which sets minimum levels of native vegetation to be maintained or restored in rural properties. In this study we simulate the impacts of alternative restoration policies addressing targets for Brazil, and explore their impacts on selected terrestrial species and agricultural development potential in the Atlantic Forest biome. Our results show several policy options could result in different restoration amounts and spatial distributions being implemented between 2020 and 2050, but trade-offs between agriculture, biodiversity and rural livelihoods differ. Compared to the baseline scenario (implementation of the Forest Code), a scenario which focuses restoration on small farms (not mandated to undergo restoration under the current legislation) could increase forest area by 6.7 Mha across the biome (139% more than with the Forest Code), while a scenario which maximizes biodiversity gains could lead to an additional 3.9 Mha by 2050 (81% more compared to the Forest Code). We find that our restoration scenarios still allow cropland expansion and an increase in cattle herd, while pasturelands decrease. There are relatively small agricultural production losses under the alternative restoration scenarios when compared to the baseline (up to 14.4%), meaning that cattle ranching intensification is critical to enable large-scale restoration to co-exist with agricultural production. Our scenarios suggest that ambitious restoration targets in the Atlantic Forest biome (up to 15.5 Mha, consistent with existing regional initiatives) could be feasible with necessary improvements in pasture yield and a focus on scaling up support and developing restoration policies for smallholder farmers.