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Green Energy & Environment 2024年第5期9卷 899-908页

作者： Weikang Hu Jiaqi Xu Nanjie chen Zongcai Deng Yuekun Lai Dongyang chen College of Materials Science and Engineering Fuzhou UniversityFuzhou350116China College of Chemical Engineering Fuzhou UniversityFuzhou350116China

The exploitation of high performance redox-active substances is critically important for the development of non-aqueous redoxﬂow ***,three tetrathiofulvalene(TTF)derivatives with different substitution groups,namely TTF diethyl ester(TTFDE),TTF tetramethyl ester(TTFTM),and TTF tetraethyl ester(TTFTE),are prepared and their energy storage properties are *** has been found that the redox potential and solubility of these TTF derivatives in conventional carbonate electrolytes increases with the number of ester *** battery with a catholyte of 0.2 mol L^(-1) of TTFTE delivers a speciﬁc capacity of more than 10 Ah L^(-1) at the current density of 0.5 C with two discharge voltage platforms locating at as high as 3.85 and 3.60 V ***/Liþ.Its capacity retention can be improved from 2.34 Ah L^(-1) to 3.60 Ah L^(-1) after 100 cycles by the use of an anion exchange membrane to block the crossover of TTF *** excellent cycling stability of the TIF esters is supported by their well-delocalized electrons,as revealed by the density function theory ***,the introduction of more and larger electron-withdrawing groups is a promising strategy to simultaneously increase the redox-potential and solubility of redox-active ma-terials for non-aqueous redoxﬂow batteries.

关键词： Non-aqueous redox flow batteries Tetrathiofulvarene Redox potential Solubility Substituent effect

Dynamic changes in physicochemical property,biogenic amines content and microbial diversity during the fermentation of Sanchuan ham

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Food Science and Human Wellness 2024年第1期13卷 506-516页

作者： Zhongai chen Hong chen Huan Du Cong chen Kaixiang Lu Qiaoli Xue Yongjin Hu College of Food Science and Technology Yunnan Agricultural UniversityKunming 650000China Institute of Food Processing Guizhou Academy of Agricultural SciencesGuiyang 550006China Editorial Department of Journal of Yunnan Agricultural University Yunnan Agricultural UniversityKunming 650000China

Sanchuan ham is appreciated in Yunnan Province,China,for its characteristic flavor and taste,while the microbial community structure and biogenic amines content remain unclear during fermentation *** this study,we explored the physicochemical property,biogenic amines concentration and microbial diversity of external and internal Sanchuan ham by high-throughput sequencing during the processing of Sanchuan *** showed that the nitrite remained at a stable level of 0.15 mg/kg which was significantly lower than the national health standard safety level of 20 mg/*** addition,compared with fresh hams,the content of total free amino acids in ripe Sanchuan ham has grown 14 folds;sour and bitter were the main tastes of Sanchuan ***,the concentration of cadaverine was the highest of all biogenic amines during the entire fermentation *** the bacterial phyla level,Firmicutes and Actinobacteria were the two main phyla,while at the genus level,Staphylococcus was a significant strain throughout the whole ***,the dry stage has a great impact on the succession change of microbial community ***,the change trends and composition of bacteria in the interior have slight discrepancies with those of the exterior of Sanchuan ham.

关键词： Sanchuan ham Nitrite cont ent Free amino acids Cadaverine Staphylococcus

Integrating phosphorus management and cropping technology for sustainable maize production

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Journal of Integrative Agriculture 2024年第4期23卷 1369-1380页

作者： Haiqing Gong Yue Xiang Jiechen Wu Laichao Luo Xiaohui chen Xiaoqiang Jiao chen chen State Key Laboratory of Nutrient Use and Management College of Resources and Environmental SciencesCollege of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China Department of Sustainable Development Environmental Science and Engineering(SEED)KTH Royal Institute of TechnologyStockholm SE-10044Sweden Anhui Province Key Lab of Farmland Ecological Conservation and Pollution Prevention School of Resources and EnvironmentAnhui Agricultural UniversityHefei 230036China Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering National Observations and Research Station for Wetland Ecosystems of the Yangtze EstuaryInstitute of Biodiversity Science and Institute of Eco-ChongmingCollege of Life SciencesFudan UniversityShanghai 200438China

Achieving high maize yields and efficient phosphorus(P)use with limited environmental impacts is one of the greatest challenges in sustainable maize *** plant density is considered an effective approach for achieving high maize ***,the low mobility of P in soils and the scarcity of natural P resources have hindered the development of methods that can simultaneously optimize P use and mitigate the P-related environmental footprint at high plant *** this study,meta-analysis and substance flow analysis were conducted to evaluate the effects of different types of mineral P fertilizer on maize yield at varying plant densities and assess the flow of P from rock phosphate mining to P fertilizer use for maize production in China.A significantly higher yield was obtained at higher plant densities than at lower plant *** application of single superphosphate,triple super-phosphate,and calcium magnesium phosphate at high plant densities resulted in higher yields and a smaller environmental footprint than the application of diammonium phosphate and monoammonium *** scenario analyses suggest that combining the optimal P type and application rate with a high plant density could increase maize yield by 22%.Further,the P resource use efficiency throughout the P supply chain increased by 39%,whereas the P-related environmental footprint decreased by 33%.Thus,simultaneously optimizing the P type and application rate at high plant densities achieved multiple objectives during maize production,indicating that combining P management with cropping techniques is a practical approach to sustainable maize *** findings offer strategic,synergistic options for achieving sustainable agricultural development.

关键词： maize plant density mineral phosphorus fertilizer meta-analysis substance flow analysis

麦冬多糖对正常和实验性糖尿病小鼠血糖的影响

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中国现代应用药学 1998年第4期15卷 21-22页

作者：陈卫辉钱华王慧中浙江省中药研究所杭州310023 浙江省林科院植物药研究中心杭州师范学院生物系

目的:研究麦冬多糖对正常和实验性糖尿病小鼠血糖的影响。方法:昆明种小鼠40只,分成4组,分别用麦冬多糖(100和300mg/kg)、优降糖(2.5mg/kg)和等体积生理盐水(2ml/只)灌胃,测定各组正常小鼠的血糖水平及以葡萄糖(2g/kg)、四氧嘧啶(70mg/... 详细信息

目的:研究麦冬多糖对正常和实验性糖尿病小鼠血糖的影响。方法:昆明种小鼠40只,分成4组,分别用麦冬多糖(100和300mg/kg)、优降糖(2.5mg/kg)和等体积生理盐水(2ml/只)灌胃,测定各组正常小鼠的血糖水平及以葡萄糖(2g/kg)、四氧嘧啶(70mg/kg)、肾上腺素(0.02mg/kg)所致小鼠高血糖模型的血糖水平。结果:剂量为100和300mg/kg的麦冬多糖灌胃对葡萄糖、四氧嘧啶及肾上腺索引起的小鼠高血糖均有抑制作用,对正常小鼠的血糖亦有降低作用。结论:麦冬多糖对正常和实验性糖尿病小鼠的血糖有明显的抑制作用。

关键词：麦冬多糖糖尿病血糖

Predicting torsional capacity of reinforced concrete members by data-driven machine learning models

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 444-460页

作者： Shenggang chen Congcong chen Shengyuan LI Junying GUO Quanquan GUO Chaolai LI School of Mechanics and Civil Engineering China University of Mining and TechnologyXuzhou 211116China Jiangsu Key Laboratory Environmental Impact and Structural Safety in Engineering China University of Mining and TechnologyXuzhou 211116China China Nuclear Power Design Co.Ltd. Shenzhen 518031China School of transportation and science engineering Beihang UniversityBeijing 100191China China Construction First Group Corporation Limited Beijing 100161China

Due to the complicated three-dimensional behaviors and testing limitations of reinforced concrete(RC)members in torsion,torsional mechanism exploration and torsional performance prediction have always been *** the present paper,several machine learning models were applied to predict the torsional capacity of RC *** results of a total of 287 torsional specimens were collected through an overall literature *** of extreme gradient boosting machine(XGBM),random forest regression,back propagation artificial neural network and support vector machine,were trained and tested by 10-fold cross-validation *** performances of proposed machine learning models were evaluated and compared,both with each other and with the calculated results of existing design codes,i.e.,GB 50010,ACI 318-19,and Eurocode *** results demonstrated that better predictive performance was achieved by machine learning models,whereas GB 50010 slightly overestimated the torsional capacity,and ACI 318-19 and Eurocode 2 underestimated it,especially in the case of ACI *** XGBM model gave the most favorable predictions with R^(2)=0.999,RMSE=1.386,MAE=0.86,andλ=***,strength of concrete was the most sensitive input parameters affecting the reliability of the predictive model,followed by transverse-to-longitudinal reinforcement ratio and total reinforcement ratio.

关键词： RC members torsional capacity machine learning models design codes

Filtering and regret network for spacecraft component segmentation based on gray images and depth maps

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Chinese Journal of Aeronautics 2024年第7期37卷 439-449页

作者： Xiang LIU Hongyuan WANG Zijian WANG Xinlong chen Weichun chen Zhengyou XIE Institute of Aeronautics Harbin Institute of TechnologyHarbin 150001China Qian Xuesen Laboratory of Space Technology China Academy of Space TechnologyBeijing 100080China

Identifying and segmenting spacecraft components is vital in many on-orbit space missions,such as on-orbit maintenance and component *** depth maps with visual images has been proven effective in improving segmentation ***,existing methods ignore the noise and fallacy in collected depth maps,which interfere with the network to extract representative features,decreasing the final segmentation *** this end,this paper proposes a Filtering and Regret Network(FRNet)for spacecraft component *** FRNet incorporates filtering and regret mechanisms to suppress the abnormal depth response in shallow layers and selectively reuses the filtered cues in deep layers,avoiding the detrimental effects of low-quality depth information while preserving the semantic context inherent in depth ***,a two-stage feature fusion module is proposed,which involves information interaction and *** module effectively explores the feature correlation and unifies the multimodal features into a comprehensive ***,a large-scale spacecraft component recognition dataset is constructed for training and evaluating spacecraft component segmentation *** results demonstrate that the FRNet achieves a state-of-the-art performance with a mean Intersection Over Union(mIOU)of 84.13%and an average inference time of 133.2 ms when tested on an NVIDIA RTX 2080 SUPER GPU.

关键词： Spacecraft component recognition Multi-modal feature fusion Satellite dataset Intelligent systems Deep learning

Transient long-range distance measurement by a Vernier spectral interferometry

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Photonics Research 2024年第6期12卷 1107-1114页

作者： LIANG XU KUN WANG chen LIU WENYING chen CHI ZHANG XINLIANG ZHANG Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China Optics Valley Laboratory Wuhan 430074China

Rapid and long-range distance measurements are essential in various industrial and scientific applications,and among them,the dual-comb ranging system attracts great attention due to its high ***,the tem-poral asynchronous sampling results in the tradeoff between frame rate and ranging precision,and the non-ambiguity range(NAR)is also limited by the comb cycle,which hinders the further advancement of the dual-comb ranging *** this constraint,we introduce a Vernier spectral interferometry to improve the frame rate and NAR of the ranging ***,leveraging the dispersive time-stretch technology,the dual-comb interferometry becomes spectral ***,the asynchronous time step is unlimited,and the frame rate is improved to 100 ***,dual-wavelength bands are introduced to implement a Vernier spectral interferometry,whose NAR is enlarged from 1.5 m to 1.5 ***,this fast and long-range system also demonstrated high precision,with a 22.91-nm Allan deviation over 10-ms averaging *** a result,the proposed Vernier spectral interferometry ranging system is promising for diverse applications that necessitate rapid and extensive distance measurement.

关键词： interferometry spectral system

Enhancing the mechanical properties of casting eutectic high -entropy alloys via W addition

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International Journal of Minerals,Metallurgy and Materials 2024年第6期31卷 1364-1372页

作者： Xu Yang Dezhi chen Li Feng Gang Qin Shiping Wu Ruirun chen National Key Laboratory for Precision Hot Processing of Metals School of Material Science and EngineeringHarbin Institute of TechnologyHarbin 150001China

The effect of W element on the microstructure evolution and mechanical properties of Al_(1.25)CoCrFeNi3 eutectic high-entropy alloy and Al_(1.25)CoCrFeNi_(3-x)W_(x)(x=0,0.05,0.1,0.3,and 0.5;atomic ratio)high-entropy alloys(HEAs)were *** show that the Al_(1.25)CoCrFeNi_(3-x)W_(x) HEAs are composed of face-centered cubic and body-centered cubic(BCC)*** W content increases,the microstructure changes from eutectic to *** addition of W lowers the nucleation barrier of the BCC phase,decreases the valence electron concentration of the HEAs,and replaces Al in the BCC phase,thus facilitating the nucleation of the BCC *** results show that the addition of W greatly improves the mechanical properties,and solid-solution,heterogeneous-interface,and second-phase strengthening are the main strengthening *** yield strength,tensile strength,and elongation of the Al_(1.25)CoCrFeNi2.95W0.05 HEA are 601.44 MPa,1132.26 MPa,and 15.94%,respectively,realizing a balance between strength and *** fracture mode of the Al_(1.25)CoCrFeNi_(3-x)W_(x) HEAs is ductile–brittle mixed fracture,and the crack propagates and initiates in the BCC *** eutectic lamellar structure impedes crack propagation and maintains plasticity.

关键词： high-entropy alloy microstructure mechanical property fracture behavior

Machine learning optimization strategy of shaped charge liner structure based on jet penetration efficiency

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DEFENCE TECHNOLOGY 2024年第9期39卷 23-41页

作者： Zhao, Ziqi Li, Tong Sheng, Donglin chen, Jian Yan, Amin chen, Yan Wang, Haiying chen, Xiaowei Dai, Lanhong Chinese Acad Sci Inst Mech State Key Lab Nonlinear Mech Beijing 100190 Peoples R China Univ Chinese Acad Sci Sch Future Technol Beijing 100049 Peoples R China Univ Chinese Acad Sci Sch Engn Sci Beijing 100049 Peoples R China Beijing Inst Technol State Key Lab Explos Sci & Technol Beijing 100081 Peoples R China

Shaped charge liner (SCL) has been extensively applied in oil recovery and defense industries. Achieving superior penetration capability through optimizing SCL structures presents a substantial challenge due to intricate rate-dependent processes involving detonation-driven liner collapse, high-speed jet stretching, and penetration. This study introduces an innovative optimization strategy for SCL structures that employs jet penetration efficiency as the primary objective function. The strategy combines experimentally validated finite element method with machine learning (FEM-ML). We propose a novel jet penetration efficiency index derived from enhanced cutoff velocity and shape characteristics of the jet via machine learning. This index effectively evaluates the jet penetration performance. Furthermore, a multi-model fusion based on a machine learning optimization method, called XGBOOST-MFO, is put forward to optimize SCL structure over a large input space. The strategy's feasibility is demonstrated through the optimization of copper SCL implemented via the FEM-ML strategy. Finally, this strategy is extended to optimize the structure of the recently emerging CrMnFeCoNi high-entropy alloy conical liners and hemispherical copper liners. Therefore, the strategy can provide helpful guidance for the engineering design of SCL. (c) 2024 China Ordnance Society. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license.

关键词： Jet penetration efficiency Shaped charge liner FEM-ML XGBOOST MFO High-entropy alloy LONG ROD PERFORMANCE COMPRESSIBILITY EXTENSION SEARCH DESIGN MODEL

Study of poly-disperse aerosols deposition in turbulent flow with different Reynolds numbers

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Particuology 2024年第6期89卷 32-43页

作者： Zhichao Gao Yongzheng chen Dandi Zhang Peng chen Lili Tong Xuewu Cao School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai200240China China Nuclear Power Technology Research Institute Co. Ltd.Shenzhen518000China

The turbulent deposition mechanism is one of the main mechanisms of aerosol deposition in nuclear power plant *** experimental study of poly-disperse aerosol deposition in a horizontal tube is conducted,where the nominal Reynolds number(Re)is in a range of 3600–200,*** aerosol deposition velocity first increases and then decreases with the increase of Res,and at high Re,particle rebound occurs during aerosol deposition in the *** the Re is low,the aerosol deposition velocity increases with the increase of aerosol *** the Re is greater than 60,000,the deposition velocity first increases and then decreases with the increase of aerosol diameter due to particle surface rebound.A new aerosol deposition model has been developed by establishing the energy conservation equation of the rebounded particles in the viscous *** calculated results of the new model are in good agreement with these experimental results,and the error between the aerosol deposition velocity calculated by the model and experimental results is between−60%and 150%.

关键词： Aerosol Turbulent deposition Rebound High Reynolds number