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Research on multi-scale simulation and dynamic verification of high dynamic MEMS components in additive manufacturing 被引量:1
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作者 Sining Lv Hengzhen Feng +2 位作者 Wenzhong Lou Chuan Xiao Shiyi Li 《Defence Technology(防务技术)》 2025年第5期275-291,共17页
Metal Additive Manufacturing(MAM) technology has become an important means of rapid prototyping precision manufacturing of special high dynamic heterogeneous complex parts. In response to the micromechanical defects s... Metal Additive Manufacturing(MAM) technology has become an important means of rapid prototyping precision manufacturing of special high dynamic heterogeneous complex parts. In response to the micromechanical defects such as porosity issues, significant deformation, surface cracks, and challenging control of surface morphology encountered during the selective laser melting(SLM) additive manufacturing(AM) process of specialized Micro Electromechanical System(MEMS) components, multiparameter optimization and micro powder melt pool/macro-scale mechanical properties control simulation of specialized components are conducted. The optimal parameters obtained through highprecision preparation and machining of components and static/high dynamic verification are: laser power of 110 W, laser speed of 600 mm/s, laser diameter of 75 μm, and scanning spacing of 50 μm. The density of the subordinate components under this reference can reach 99.15%, the surface hardness can reach 51.9 HRA, the yield strength can reach 550 MPa, the maximum machining error of the components is 4.73%, and the average surface roughness is 0.45 μm. Through dynamic hammering and high dynamic firing verification, SLM components meet the requirements for overload resistance. The results have proven that MEM technology can provide a new means for the processing of MEMS components applied in high dynamic environments. The parameters obtained in the conclusion can provide a design basis for the additive preparation of MEMS components. 展开更多
关键词 Additive manufacturing High dynamic MEMS components Multiscale control Process optimization High dynamic verification
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Simultaneous identification of multiple animal-derived components in meat and meat products by using MNP marker based on high-throughput sequencing 被引量:1
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作者 Yan Yi Zhanyue Jiang +9 位作者 Lixia Ma Xiaoni Hou Lun Li Deping Ye Juanlan Du Hai Peng Guoquan Han Huaiping Li Jiangwen Tang Lihua Zhou 《Food Science and Human Wellness》 2025年第4期1566-1575,共10页
In order to save manpower and time costs,and to achieve simultaneous detection of multiple animal-derived components in meat and meat products,this study used multiple nucleotide polymorphism(MNP)marker technology bas... In order to save manpower and time costs,and to achieve simultaneous detection of multiple animal-derived components in meat and meat products,this study used multiple nucleotide polymorphism(MNP)marker technology based on the principle of high-throughput sequencing,and established a multi-locus 10 animalderived components identification method of cattle,goat,sheep,donkey,horse,chicken,duck,goose,pigeon,quail in meat and meat products.The specific loci of each species could be detected and the species could be accurately identified,including 5 loci for cattle and duck,3 loci for sheep,9 loci for chicken and horse,10 loci for goose and pigeon,6 loci for quail and 1 locus for donkey and goat,and an adulteration model was established to simulate commercially available samples.The results showed that the method established in this study had high throughput,good repeatability and accuracy,and was able to identify 10 animalderived components simultaneously with 100%repeatability accuracy.The detection limit was 0.1%(m/m)in simulated samples of chicken,duck and horse.Using the method established in this study to test commercially available samples,4 samples from 14 commercially available samples were detected to be inconsistent with the labels,of which 2 did not contain the target ingredient and 2 were adulterated with small amounts of other ingredients. 展开更多
关键词 Meat and meat products Multiple nucleotide polymorphism marker method High-throughput sequencing Animal-derived component identification
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Prediction of joint roughness coefficient via hybrid machine learning model combined with principal components analysis 被引量:1
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作者 Shijie Xie Hang Lin +2 位作者 Tianxing Ma Kang Peng Zhen Sun 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第4期2291-2306,共16页
Joint roughness coefficient(JRC)is the most commonly used parameter for quantifying surface roughness of rock discontinuities in practice.The system composed of multiple roughness statistical parameters to measure JRC... Joint roughness coefficient(JRC)is the most commonly used parameter for quantifying surface roughness of rock discontinuities in practice.The system composed of multiple roughness statistical parameters to measure JRC is a nonlinear system with a lot of overlapping information.In this paper,a dataset of eight roughness statistical parameters covering 112 digital joints is established.Then,the principal component analysis method is introduced to extract the significant information,which solves the information overlap problem of roughness characterization.Based on the two principal components of extracted features,the white shark optimizer algorithm was introduced to optimize the extreme gradient boosting model,and a new machine learning(ML)prediction model was established.The prediction accuracy of the new model and the other 17 models was measured using statistical metrics.The results show that the prediction result of the new model is more consistent with the real JRC value,with higher recognition accuracy and generalization ability. 展开更多
关键词 Rock discontinuities Joint roughness coefficient(JRC) Roughness characterization Principal components analysis(PCA) Machine learning
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Based on non-targeted metabolomics for differential components screening of Rosae Chinensis Flos and Rosae Rugosae Flos and their quality evaluation
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作者 Xu Liang Ni-Hui Zhang +4 位作者 Zhi-Lai Zhan Guang-Lu Chang Yan Gao Xia Li Wen-Yuan Gao 《Traditional Medicine Research》 2025年第2期1-15,共15页
Background:Rosa chinensis Jacq.and Rosa rugosa Thunb.are not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional medicines.The two plants h... Background:Rosa chinensis Jacq.and Rosa rugosa Thunb.are not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional medicines.The two plants have some differences in efficacy,but the flower buds are easily confused for similar traits.In addition,large-scale cultivation of ornamental rose flowers may lead to a decrease in the effective components of medicinal roses.Therefore,it is necessary to study the chemical composition and make quality evaluation of Rosae Chinensis Flos(Yueji)and Rosae Rugosae Flos(Meigui).Methods:In this study,40 batches of samples including Meigui and Yueji from different regions in China were collected to establish high-performance liquid chromatography fingerprints.Then,the fingerprints data was analyzed using principal component analysis,hierarchical cluster analysis,and partial least squares discriminant analysis analysis chemometrics to obtain information on intergroup differences,and non-targeted metabolomic techniques were applied to identify and compare chemical compositions of samples which were chosen from groups with large differences.Differential compounds were screened by orthogonal partial least-squares discriminant analysis and S-plot,and finally multi-component quantification was performed to comprehensively evaluate the quality of Yueji and Meigui.Results:The similarity between the fingerprints of 40 batches roses and the reference print R was 0.73 to 0.93,indicating that there were similarities and differences between the samples.Through principal component analysis and hierarchical cluster analysis of fingerprints data,the samples from different origins and varieties were intuitively divided into four groups.Partial least-squares discriminant analysis analysis showed that Meigui and Yueji cluster into two categories and the model was reliable.A total of 89 compounds were identified by high resolution mass spectrometry,mainly were flavonoids and flavonoid glycosides,as well as phenolic acids.Eight differential components were screened out by orthogonal partial least-squares discriminant analysis and S-plot analysis.Quantitative analyses of the eight compounds,including gallic acid,ellagic acid,hyperoside,isoquercitrin,etc.,showed that Yueji was generally richer in phenolic acids and flavonoids than Meigui,and the quality of Yueji from Shandong and Hebei was better.It is worth noting that Xinjiang rose is rich in various components,which is worth focusing on more in-depth research.Conclusion:In this study,the fingerprints of Meigui and Yueji were established.The chemical components information of roses was further improved based on non-targeted metabolomics and mass spectrometry technology.At the same time,eight differential components of Meigui and Yueji were screened out and quantitatively analyzed.The research results provided a scientific basis for the quality control and rational development and utilization of Rosae Chinensis Flos and Rosae Rugosae Flos,and also laid a foundation for the study of their pharmacodynamic material basis. 展开更多
关键词 Rosa chinensis Jacq. Rosa rugosa Thunb. metabolomics CHEMOMETRICS multiple component quantification quality evaluation
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Influencing factor of the characterization and restoration of phase aberrations resulting from atmospheric turbulence based on Principal Component Analysis
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作者 WANG Jiang-pu-zhen WANG Zhi-qiang +2 位作者 ZHANG Jing-hui QIAO Chun-hong FAN Cheng-yu 《中国光学(中英文)》 北大核心 2025年第4期899-907,共9页
Restoration of phase aberrations is crucial for addressing atmospheric turbulence in light propagation.Traditional restoration algorithms based on Zernike polynomials(ZPs)often encounter challenges related to high com... Restoration of phase aberrations is crucial for addressing atmospheric turbulence in light propagation.Traditional restoration algorithms based on Zernike polynomials(ZPs)often encounter challenges related to high computational complexity and insufficient capture of high-frequency phase aberration components,so we proposed a Principal-Component-Analysis-based method for representing phase aberrations.This paper discusses the factors influencing the accuracy of restoration,mainly including the sample space size and the sampling interval of D/r_(0),on the basis of characterizing phase aberrations by Principal Components(PCs).The experimental results show that a larger D/r_(0)sampling interval can ensure the generalization ability and robustness of the principal components in the case of a limited amount of original data,which can help to achieve high-precision deployment of the model in practical applications quickly.In the environment with relatively strong turbulence in the test set of D/r_(0)=24,the use of 34 terms of PCs can improve the corrected Strehl ratio(SR)from 0.007 to 0.1585,while the Strehl ratio of the light spot after restoration using 34 terms of ZPs is only 0.0215,demonstrating almost no correction effect.The results indicate that PCs can serve as a better alternative in representing and restoring the characteristics of atmospheric turbulence induced phase aberrations.These findings pave the way to use PCs of phase aberrations with fewer terms than traditional ZPs to achieve data dimensionality reduction,and offer a reference to accelerate and stabilize the model and deep learning based adaptive optics correction. 展开更多
关键词 phase aberration atmospheric turbulence principal component analysis Zernike polynomials
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基于Visual Components数字孪生平台的伺服运动控制系统开发
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作者 朱红娟 顾晟吉 《南方农机》 2025年第18期113-117,共5页
选择合适的数字孪生平台可以更好地运行和预测系统行为,提高生产效率并降低成本。为了加快数字孪生项目搭建速度,降低初期投入成本,文章提出了一种面向数字孪生平台的伺服运动控制系统。基于SolidWorks三维设计软件和VC平台搭建伺服控... 选择合适的数字孪生平台可以更好地运行和预测系统行为,提高生产效率并降低成本。为了加快数字孪生项目搭建速度,降低初期投入成本,文章提出了一种面向数字孪生平台的伺服运动控制系统。基于SolidWorks三维设计软件和VC平台搭建伺服控制虚拟仿真系统,在仿真过程中使用Python API脚本行为进行伺服运动控制系统开发,利用OPC UA通信接口实现虚拟样机与真实样机之间的数据交互,将虚拟现实技术应用于工业生产中,实时监控系统的运行状态。最终实现了以数字虚拟模型控制实体样机的运行状态,从而实现了对伺服运动控制系统数据的实时可视化呈现以及相应的异常数据预警功能,有助于减少后续对模型的修改。 展开更多
关键词 Visual components Python API脚本开发 伺服运动
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Acetabular Component Positioning and Risk of Dislocation in Hip Arthroplasty: Is Lewinnek’s Safe Zone Truly Safe?
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作者 Oliver Damiani Meyer Luis Henrique Zambra Wink +3 位作者 Walter Brandt Iserhard Carlos Roberto Schwartsmann Anthony Kerbes Yépez Leandro de Freitas Spinelli 《Open Journal of Orthopedics》 2025年第2期47-53,共7页
Objective: The present research aims to determine if adherence to the Lewinnek safe zone, when exclusively considered, constitutes a pivotal element for ensuring stability in the context of total hip arthroplasty. Thi... Objective: The present research aims to determine if adherence to the Lewinnek safe zone, when exclusively considered, constitutes a pivotal element for ensuring stability in the context of total hip arthroplasty. This is done by examining the acetabular placement in instances of hip dislocation after total hip arthroplasty (THA). Methodology: The authors searched 2653 patient records from 2015 to 2022 looking for patients who had total hip arthroplasty at our facility. For the analysis, 23 patients were culled from 64 individuals who exhibited post-THA dislocations, employing a stringent exclusion criterion, and the resultant acetabular angulation and anteversion were quantified utilizing PEEKMED software (Peek Health S.A., Portugal) upon radiographic evidence. Results: Within the operational timeframe, from the cohort of 2653 subjects, 64 presented with at least a singular incident of displacement. Post-exclusion criterion enforcement, 23 patients were eligible for inclusion. Of these, 10 patients conformed to the safe zone demarcated by Lewinnek for both inclination and anteversion angles, while 13 exhibited deviations from the prescribed anteversion and/or inclination benchmarks. Conclusion: Analysis of the 23 patients reveals that 13 did not confirm to be in the safe zone parameters for anteversion and/or inclination, whereas 10 were within the safe zone as per Lewinnek’s guidelines. This investigative review, corroborated by extant literature, suggests that the isolated consideration of the Lewinnek safe zone does not suffice as a solitary protective factor. It further posits that additional variables are equally critical as acetabular positioning and mandate individual assessment. 展开更多
关键词 Acetabular component Positioning DISLOCATION Hip Arthroplasty Lewinnek’s Safe Zone
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The serum fascin-1 and tumor components containing this protein in patients with head and neck squamous cell carcinoma:A pilot study 被引量:1
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作者 Gelena V.Kakurina Elena E.Sereda +4 位作者 Marina N.Stakheeva Liubov Tashireva Olga V.Cheremisina Irina V.Kondakova Evgeny L.Choinzonov 《Journal of Biomedical Research》 2025年第5期534-537,I0046,I0047,共6页
Dear Editor,Local recurrence and cervical lymph node metastases are major causes of mortality in patients with head and neck squamous cell carcinoma(HNSCC).To date,none of the proposed strategies for predicting outcom... Dear Editor,Local recurrence and cervical lymph node metastases are major causes of mortality in patients with head and neck squamous cell carcinoma(HNSCC).To date,none of the proposed strategies for predicting outcomes in this disease have proven fully effective,and a comprehensive physical examination remains the primary method for early detection and monitoring of HNSCC. 展开更多
关键词 serum fascin cervical lymph node metastases tumor components comprehensive physical examination head neck squamous cell carcinoma hnscc head neck squamous cell carcinoma pilot study local recurrence
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Assessment of Spatial Water Quality Variations in Shallow Wells Using Principal Component Analysis in Half London Ward, Tanzania
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作者 Matungwa William Zacharia Katambara 《Journal of Water Resource and Protection》 2025年第2期108-143,共36页
Groundwater is a crucial water source for urban areas in Africa, particularly where surface water is insufficient to meet demand. This study analyses the water quality of five shallow wells (WW1-WW5) in Half-London Wa... Groundwater is a crucial water source for urban areas in Africa, particularly where surface water is insufficient to meet demand. This study analyses the water quality of five shallow wells (WW1-WW5) in Half-London Ward, Tunduma Town, Tanzania, using Principal Component Analysis (PCA) to identify the primary factors influencing groundwater contamination. Monthly samples were collected over 12 months and analysed for physical, chemical, and biological parameters. The PCA revealed between four and six principal components (PCs) for each well, explaining between 84.61% and 92.55% of the total variance in water quality data. In WW1, five PCs captured 87.53% of the variability, with PC1 (33.05%) dominated by pH, EC, TDS, and microbial contamination, suggesting significant influences from surface runoff and pit latrines. In WW2, six PCs explained 92.55% of the variance, with PC1 (36.17%) highlighting the effects of salinity, TDS, and agricultural runoff. WW3 had four PCs explaining 84.61% of the variance, with PC1 (39.63%) showing high contributions from pH, hardness, and salinity, indicating geological influences and contamination from human activities. Similarly, in WW4, six PCs explained 90.83% of the variance, where PC1 (43.53%) revealed contamination from pit latrines and fertilizers. WW5 also had six PCs, accounting for 92.51% of the variance, with PC1 (42.73%) indicating significant contamination from agricultural runoff and pit latrines. The study concludes that groundwater quality in Half-London Ward is primarily affected by a combination of surface runoff, pit latrine contamination, agricultural inputs, and geological factors. The presence of microbial contaminants and elevated nitrate and phosphate levels underscores the need for improved sanitation and sustainable agricultural practices. Recommendations include strengthening sanitation infrastructure, promoting responsible farming techniques, and implementing regular groundwater monitoring to safeguard water resources and public health in the region. 展开更多
关键词 Groundwater Contamination Principal component Analysis (PCA) Shallow Well Water Quality Anthropogenic Pollution Hydrogeological Processes
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Review and Future Perspectives on Lithium Battery Fire Safety:Focusing on Design of Organic Components
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作者 Qianlong Li Yunlei Xu +2 位作者 Ye-Tang Pan Wei Wang Guan Heng Yeoh 《Energy & Environmental Materials》 2025年第4期3-20,共18页
The widespread use of lithium batteries has led to frequent fire hazards,which significantly threaten both human lives and property safety.One of the primary challenges in enhancing the fire safety of lithium batterie... The widespread use of lithium batteries has led to frequent fire hazards,which significantly threaten both human lives and property safety.One of the primary challenges in enhancing the fire safety of lithium batteries lies in the flammability of their organic components.As electronic devices continue to proliferate,the integration of liquid electrolytes and separators has become common.However,these components are prone to high volatility and leakage,which limits their safety.Fortunately,recent advancements in solid-state and gel electrolytes have demonstrated promising performance in laboratory settings,providing solutions to these issues.Typically,improving the flame retardancy and fire safety of lithium batteries involves careful design of the formulations or molecular structures of the organic materials.Moreover,the internal interfacial interactions also play a vital role in ensuring safety.This review examines the innovative design strategies developed over the past 5 years to address the fire safety concerns associated with lithium batteries.Future advancements in the next generation of high-safety lithium batteries should not only focus on optimizing component design but also emphasize rigorous operational testing.This dual approach will drive further progress in battery safety research and development,enhancing the overall reliability of lithium battery systems. 展开更多
关键词 component design fire safety flame retardant lithiumbattery NONFLAMMABLE
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Hydrogeochemical Processes in Basement Areas Using Principal Component in Burkina Faso (West African Sahel)
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作者 Moussa Diagne Faye Vini Yves Bernadin Loyara +4 位作者 Amadou Keita Mamadou Diop Angelbert Chabi Biaou Mahamadou Koita Hamma Yacouba 《Journal of Environmental & Earth Sciences》 2025年第1期1-17,共17页
The basement aquifers in Burkina Faso are increasingly exposed to groundwater pollution,largely due to socio-economic activities and climatic fluctuations,particularly the reduction in rainfall.This pollution makes th... The basement aquifers in Burkina Faso are increasingly exposed to groundwater pollution,largely due to socio-economic activities and climatic fluctuations,particularly the reduction in rainfall.This pollution makes the management and understanding of these aquifers particularly complex.To elucidate the processes controlling this contamination,a methodological approach combining principal component analysis(PCA)and multivariate statistical techniques was adopted.The study analyzed sixteen physicochemical parameters from 58 water samples.The primary objective of this research is to assess groundwater quality and deepen the understanding of the key factors influencing the spatial variation of their chemical composition.The results obtained will contribute to better planning of preservation and sustainable management measures for water resources in Burkina Faso.The results show that three principal components explain 72%of the variance,identifying anthropogenic inputs,with two components affected by mineralization and one by pollution.The study reveals that the groundwater is aggressive and highly corrosive,with calcite saturation.Water-rock interactions appear to be the main mechanisms controlling the hydrochemistry of groundwater,with increasing concentrations of cations and anions as the water travels through percolation pathways.PCA also revealed that the residence time of the water and leaching due to human activities significantly influence water quality,primarily through mineralization processes.These results suggest that rock weathering,coupled with reduced rainfall,constitutes a major vulnerability for aquifer recharge. 展开更多
关键词 GROUNDWATER HYDROGEOCHEMISTRY Spatial Analysis Principal component Analysis
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Reflections on recent advances in component-based Chinese medicine
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作者 Zi-Bin Lu 《Integrative Medicine Discovery》 2025年第13期1-2,共2页
Component-based Chinese Medicine(CCM)stands as a pivotal endeavor in modernizing traditional Chinese medicine(TCM).By integrating classical TCM theories with modern scientific methodologies,CCM aims to achieve herbal ... Component-based Chinese Medicine(CCM)stands as a pivotal endeavor in modernizing traditional Chinese medicine(TCM).By integrating classical TCM theories with modern scientific methodologies,CCM aims to achieve herbal formulas with“defined components,clarified mechanisms,and controllable quality.”This approach not only transitions TCM development from empirical tradition to evidence-based science but also positions it for global recognition.Drawing on recent advancements in CCM,this editorial explores key insights and challenges shaping its trajectory. 展开更多
关键词 modernizing traditional chinese medicine tcm clarified mechanisms modern scientific methodologiesccm component based Chinese medicine traditional Chinese medicine defined components evidence based science herbal formulas
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Revealing the Effect of Non-rubber Components of Natural Rubber on Its Radiation Resistance Performance
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作者 En-Tao Luo Liang Jing +5 位作者 Ling-Min Kong Yu Peng Hao Luo Li-Juan Zhao Zheng-Tian Xie Jin-Rong Wu 《Chinese Journal of Polymer Science》 2025年第7期1190-1199,共10页
Natural rubber(NR)is a crucial elastic material used for damping and sealing applications in the nuclear industry,but its mechanical stability under radiation remains inadequate.Current efforts to improve radiation re... Natural rubber(NR)is a crucial elastic material used for damping and sealing applications in the nuclear industry,but its mechanical stability under radiation remains inadequate.Current efforts to improve radiation resistance rely on the addition of antiradiation agents,however,the effects of the components and microstructures of NR itself on radiation resistance remain unclear.In this study,we compared the composition and structure differences of four typical commercially used NR materials and investigated their effects on gamma radiation resistance.Furthermore,we examined the impact of non-rubber components(NRC)in NR on radiation resistance using deproteinized and dephosphorylated NR model samples.Our results revealed that NRC,such as proteins and phospholipids can enhance the strength of natural rubber before radiation exposure.However,after the removal of NRC,the samples exhibited improved mechanical stability under irradiation.Additionally,the ash content in NR could also influence the radiation resistance,as metal ions may react with the active centers produced by radiation,thereby enhancing the radiation resistance of the rubber.This work identifies the effect of non-rubber components in NR on radiation resistance and may serve as a reference for screening and developing radiation-resistant NR materials. 展开更多
关键词 Natural rubber Non-rubber components Radiation resistance
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Therapeutic components of acupuncture stimulation based on characteristics of sensory nerve and nervous signaling pathway
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作者 Hyo-Sun Wie Seung-Nam Kim 《Journal of Integrative Medicine》 2025年第2期106-112,共7页
Acupuncture,a therapeutic practice rooted in traditional Chinese medicine and integrated with modern neuroscience,achieves its effects by stimulating sensory nerves at specific anatomical points known as acupoints.Thi... Acupuncture,a therapeutic practice rooted in traditional Chinese medicine and integrated with modern neuroscience,achieves its effects by stimulating sensory nerves at specific anatomical points known as acupoints.This review systematically explores the therapeutic components of acupuncture,emphasizing the interplay between sensory nerve characteristics and neural signaling pathways.Key factors such as acupoint location,needling depth,stimulation intensity,retention time,and the induction of sensations(e.g.,Deqi)are analyzed for their roles in neural activation and clinical outcomes.The review highlights how variations in spinal segment targeting,tissue-specific receptor activation,and stimulation modalities(e.g.,manual acupuncture,electroacupuncture,moxibustion)influence therapeutic effects.Emerging evidence underscores the significance of ion channels,dermatomes,myotomes,and genespecific pathways in mediating systemic effects.Additionally,the differential roles of mechanical,thermal and nociceptive stimuli and the temporal dynamics of sensory and immune responses are addressed.While insights from animal models have advanced our understanding,their translation to clinical practice requires further investigation.This comprehensive review identifies critical parameters for optimizing acupuncture therapy,advocating for individualized treatment strategies informed by neuroanatomical and neurophysiological principles,ultimately enhancing its precision and efficacy in modern medicine. 展开更多
关键词 Sensory nerve ACUPUNCTURE Nervous system Therapeutic component Acupuncture point MERIDIANS
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Numerical Simulation on Heat Dissipation Characteristics of Electronic Components with Different Heat Sink Arrangements in High-Performance Server
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作者 Zerui Chen Xin Wu +2 位作者 Houpeng Hu Yang Zhou Shang Yang 《Frontiers in Heat and Mass Transfer》 2025年第3期991-1011,共21页
As the integration of electronic components in high-performance servers increases,heat generation significantly impacts performance and raises failure rates.Therefore,heat dissipation has become a critical concern in ... As the integration of electronic components in high-performance servers increases,heat generation significantly impacts performance and raises failure rates.Therefore,heat dissipation has become a critical concern in electronic circuit design.This study uses numerical simulations to investigate the heat dissipation characteristics of electronic components in air-cooled servers.By adjusting airflow speed,heat sink configurations,and the arrangement of straight-fin heat sinks,we optimize heat dissipation performance and analyze the mechanisms at different airflow speeds.The results show that,at the same airflow speed,the temperature of the heat sink is lower than that of the electronic components,creating a temperature gradient that enhances heat transfer.Compared to a front-to-back arrangement of two straight-fin heat sinks,placing the heat sinks parallel to each other results in a lower maximum component temperature and better temperature uniformity.Heat sinks with fins significantly improve heat dissipation.The heat sink with semicylindrical fins on the rib surface provides the best cooling performance.Moreover,compared to natural convection,the maximum temperature of the electronic components decreases by 56.17%and 61%when the incoming flow velocity is 6 m/s with two parallel flat ribbed heat sinks and front-to-back arrangement,respectively. 展开更多
关键词 Electronic components numerical simulation heat dissipation structure optimization
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Analysis of Chemical Components of Cocculus laurifolius DC.Based on Liquid Chromatography-Mass Spectrometry
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作者 Lintong HAN Yuzhe LI +5 位作者 Chengxin LAN Bolin BAO Yajie WEI Haicheng WEN Wei WEI Xiaoman ZHONG 《Medicinal Plant》 2025年第1期16-18,共3页
[Objectives]To analyze the main chemical components in Cocculus laurifolius DC.by ultra-high performance liquid chromatography-quaternary rod/electrostatic field orbital hydrazine high resolution mass spectrometry.[Me... [Objectives]To analyze the main chemical components in Cocculus laurifolius DC.by ultra-high performance liquid chromatography-quaternary rod/electrostatic field orbital hydrazine high resolution mass spectrometry.[Methods]Using Welch AQ-C 18 chromatographic column(150 mm×2.1 mm,1.8μm),gradient elution was performed with 0.1%formic acid aqueous solution(A)-methanol(B)as the mobile phase,and electrospray ESI ionization source and simultaneous mass spectrometry scanning mode of positive and negative ions were used.[Results]26 kinds of chemical component were identified or inferred,including 3 organic acids,5 flavonoids,4 alkaloids,1 coumarin and 13 others.[Conclusions]The UPLC-Q-Exactive HRMS technique is simple,which lays a foundation for the drug-efficacy material basis and medicinal quality evaluation of C.laurifolius DC. 展开更多
关键词 Cocculus laurifolius DC. UPLC-Q-Exactive HRMS Chemical component ALKALOIDS FLAVONOIDS
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Fracture Properties of Self-Compacting Concrete Incorporating Multiple Toughening Components
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作者 CHENG Zhiqing YANG Kai +4 位作者 TANG Zhuo ZHAO Hong GE Fei WU Hao LONG Guangcheng 《Journal of Wuhan University of Technology(Materials Science)》 2025年第5期1310-1319,共10页
Three typical toughening components(i e,emulsion asphalt,waste tire rubber particles,and polyethylene fibers)were employed to prepare self-compacting concrete(SCC).The fracture behaviors of these prepared SCC were inv... Three typical toughening components(i e,emulsion asphalt,waste tire rubber particles,and polyethylene fibers)were employed to prepare self-compacting concrete(SCC).The fracture behaviors of these prepared SCC were investigated through the three-point bending test of notched beams,in which the accompanying acoustics emissions(AE)were also recorded.The test results showed that although incorporating a single toughening component reduced the fracture strengths and fracture toughness of SCC,the combination of multiple toughening components could diminish this negative effect.In addition,introducing toughening components could enhance the fracture energy and ductility index of SCC,with an improvement up to 10 times or more when PE fibers and other toughening components were involved.Based on the results of AE characteristics,SCC exhibited a progressive damage process with mitigated crack propagation after the addition of toughening components.Overall,this study could advance the understanding of the influence mechanisms of toughening components on concrete fracture behavior and further instruct the improvement in the fracture performance of concrete. 展开更多
关键词 self-compacting concrete toughening component fracture property acoustic emission
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Association analysis of an anti-obesity mechanism and key ripened Pu-erh tea bioactive components by mimicking human general tea drinking
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作者 Junyu Liu Zhengyang Song +12 位作者 Haihong Chen Wen Zeng Guirong Han Wei Li Bing Xu Yuan Lu Canyang Zhang Zhenglian Xue Bin Lü Chong Zhang Song Yang Yi Wang Xinhui Xing 《Food Science and Human Wellness》 2025年第2期450-468,共19页
Pu-erh tea,a traditional Chinese beverage,performs an anti-obesity function,but the correlation between its components and efficacy remains unknown.Here,we screened two Pu-erh teas with significant anti-obesity effica... Pu-erh tea,a traditional Chinese beverage,performs an anti-obesity function,but the correlation between its components and efficacy remains unknown.Here,we screened two Pu-erh teas with significant anti-obesity efficacies from 11 teas.In vitro experiments revealed that lipid accumulation in L02 cells and lipid synthesis in 3T3-L1 cells were significantly better inhibited by Tea-B than Tea-A.Further in vivo experiments using model mice revealed that the differences in chemical components generated two pathways in the anti-obesity efficacy and mechanism of Pu-erh teas.Tea-A changes the histomorphology of brown adipose tissue(BAT)and increases the abundance of Coriobacteriaceae_UCG_002 and cyclic AMP in guts through high chemical contents of cyclopentasiloxane,decamethyl,tridecane and 1,2,3-trimethoxybenzene,eventually increasing BAT activation and fat browning gene expression;the high content of hexadecane and 1,2-dimethoxybenzene in Tea-B reduces white adipose tissue(WAT)accumulation and the process of fatty liver,increases the abundance of Odoribacter and sphinganine 1-phosphate,inhibits the expression of lipid synthesis and transport genes.These mechanistic findings on the association of the representative bioactive components in Pu-erh teas with the anti-obesity phenotypes,gut microbes,gut metabolite structure and anti-obesity pathways,which were obtained for the first time,provide foundations for developing functional Pu-erh tea. 展开更多
关键词 ANTI-OBESITY Bioactive components Lipid metabolism Multiomics analysis Pu-erh tea
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Refining GNSS-based water storage estimation:Improved hydrological signal extraction using principal component analysis
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作者 Jiaxiang Tian Yulong Zhong +4 位作者 Yingchun Shen Kaijun Yang Hongbing Bai Fan Lei Changqing Wang 《Geodesy and Geodynamics》 2025年第5期591-603,共13页
The Global Navigation Satellite System(GNSS)is vital for monitoring terrestrial water storage(TWS).However,effectively extracting hydrological load deformation from GNSS observations poses a significant challenge.This... The Global Navigation Satellite System(GNSS)is vital for monitoring terrestrial water storage(TWS).However,effectively extracting hydrological load deformation from GNSS observations poses a significant challenge.This study proposes a novel strategy;the seasonal hydrological load signals are removed from the raw data,and the remaining signals use principal component analysis(PCA).Simulation results from Yunnan Province demonstrate that the spatial distribution of the root mean square error(RMSE)is improved by approximately 15% compared with traditional PCA extraction from raw data.From January 2013 to December 2022,TWS was inverted from 24 GNSS stations in Yunnan Province.The spatial distribution and time series of TWS inverted from GNSS align well with those TWS inferred from the Gravity Recovery and Climate Experiment(GRACE),GRACE Follow-On(GFO),and the Global Land Data Assimilation System(GLDAS)land surface model.However,the amplitude of the GNSS-inverted TWS is slightly higher.Since GNSS ground stations are more sensitive to hydrological load signals,they show correlations with precipitation data that are 8.6%and 6.0%higher than those of GRACE and GLDAS,respectively.In the power spectral density analysis of GRACE/GFO,GLDAS,and GNSS,the signal strength of GNSS is much higher than that of GRACE/GFO and GLDAS in the June and February cycles.These findings suggest that the new data extraction strategy can capture higher frequency hydrological signals in TWS,and GNSS observations can help address limitations in GRACE/GFO observations.This study demonstrates the potential of GNSS TWS in capturing higher-frequency hydrological signals and climate extremes application. 展开更多
关键词 Hydrography GNSS Green's function Principal component analysis Yunnan Province
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Research Progress on Chemical Components of Trichosanthis Fructus
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作者 Donghai CHU Xiang LI 《Agricultural Biotechnology》 2025年第3期24-28,32,共6页
Trichosanthis Fructus(Gualou)is the dried ripe fruit of Trichosanthes kirilowii Maxim.or Trichosanthes rosthornii Harms(Cucurbitaceae family).It demonstrates significant therapeutic effects in treating coronary heart ... Trichosanthis Fructus(Gualou)is the dried ripe fruit of Trichosanthes kirilowii Maxim.or Trichosanthes rosthornii Harms(Cucurbitaceae family).It demonstrates significant therapeutic effects in treating coronary heart disease and diabetes mellitus,while also possessing anti-cancer and anti-aging properties.Both Trichosanthis Pericarpium(Gualoupi)and Trichosanthis Semen(Gualouzi)are used medicinally.With the increasing clinical application of Trichosanthes medicinal materials and their preparations(such as Gualou Injection and Gualou Tablets),the demand for them is expected to grow substantially.To further investigate Trichosanthis Fructus,explore its medicinal effects and new applications,and promote the development of Trichosanthis Fructus-based products,this paper reviewed the chemical components of Trichosanthis Fructus.Furthermore,the differences in major chemical components among Trichosanthis Fructus,Trichosanthis Pericarpium and Trichosanthis Semen were compared,providing a scientific basis for establishing quality evaluation standards of Trichosanthes medicinal materials. 展开更多
关键词 Trichosanthis Fructus Trichosanthis Pericarpium Trichosanthis Semen Chemical components
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