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Eliminating H_(2)O/HF and regulating interphase with bifunctional tolylene-2,4-diisocyanate(TDI)additive for long life Li-ion battery 被引量:2
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作者 Xueyi Zeng Xiang Gao +8 位作者 Peiqi Zhou Haijia Li Xin He Weizhen Fan Chaojun Fan Tianxiang Yang Zhen Ma Xiaoyang Zhao Junmin Nan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期519-528,I0011,共11页
Lithium-ion batteries(LIBs)featuring a Ni-rich cathode exhibit increased specific capacity,but the establishment of a stable interphase through the implementation of a functional electrolyte strategy remains challengi... Lithium-ion batteries(LIBs)featuring a Ni-rich cathode exhibit increased specific capacity,but the establishment of a stable interphase through the implementation of a functional electrolyte strategy remains challenging.Especially when the battery is operated under high temperature,the trace water present in the electrolyte will accelerate the hydrolysis of the electrolyte and the resulting HF will further erode the interphase.In order to enhance the long-term cycling performance of graphite/LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(NCM811)LIBs,herein,Tolylene-2,4-diisocyanate(TDI)additive containing lone-pair electrons is employed to formulate a novel bifunctional electrolyte aimed at eliminating H_(2)O/HF generated at elevated temperature.After 1000 cycles at 25℃,the battery incorporating the TDI-containing electrolyte exhibits an impressive capacity retention of 94%at 1 C.In contrast,the battery utilizing the blank electrolyte has a lower capacity retention of only 78%.Furthermore,after undergoing 550 cycles at 1 C under45℃,the inclusion of TDI results in a notable enhancement of capacity,increasing it from 68%to 80%.This indicates TDI has a favorable influence on the cycling performance of LIBs,especially at elevated temperatures.The analysis of the film formation mechanism suggests that the lone pair of electrons of the isocyanate group in TDI play a crucial role in inhibiting the generation of H_(2)O and HF,which leads to the formation of a thin and dense interphase.The existence of this interphase is thought to substantially enhance the cycling performance of the LIBs.This work not only improves the performance of graphite/NCM811 batteries at room temperature and high temperature by eliminating H_(2)O/HF but also presents a novel strategy for advancing functional electrolyte development. 展开更多
关键词 Graphite/LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)battery Tolylene-2 4-diisocyanate Long-cycling performance H_(2)O/HF eliminated additive
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Smart prediction of liquefaction-induced lateral spreading 被引量:1
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作者 Muhammad Nouman Amjad Raja Tarek Abdoun Waleed El-Sekelly 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2310-2325,共16页
The prediction of liquefaction-induced lateral spreading/displacement(Dh)is a challenging task for civil/geotechnical engineers.In this study,a new approach is proposed to predict Dh using gene expression programming(... The prediction of liquefaction-induced lateral spreading/displacement(Dh)is a challenging task for civil/geotechnical engineers.In this study,a new approach is proposed to predict Dh using gene expression programming(GEP).Based on statistical reasoning,individual models were developed for two topographies:free-face and gently sloping ground.Along with a comparison with conventional approaches for predicting the Dh,four additional regression-based soft computing models,i.e.Gaussian process regression(GPR),relevance vector machine(RVM),sequential minimal optimization regression(SMOR),and M5-tree,were developed and compared with the GEP model.The results indicate that the GEP models predict Dh with less bias,as evidenced by the root mean square error(RMSE)and mean absolute error(MAE)for training(i.e.1.092 and 0.815;and 0.643 and 0.526)and for testing(i.e.0.89 and 0.705;and 0.773 and 0.573)in free-face and gently sloping ground topographies,respectively.The overall performance for the free-face topology was ranked as follows:GEP>RVM>M5-tree>GPR>SMOR,with a total score of 40,32,24,15,and 10,respectively.For the gently sloping condition,the performance was ranked as follows:GEP>RVM>GPR>M5-tree>SMOR with a total score of 40,32,21,19,and 8,respectively.Finally,the results of the sensitivity analysis showed that for both free-face and gently sloping ground,the liquefiable layer thickness(T_(15))was the major parameter with percentage deterioration(%D)value of 99.15 and 90.72,respectively. 展开更多
关键词 Lateral spreading Intelligent modeling Gene expression programming(GEP) Closed-form solution Feature importance
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Differentially private SGD with random features
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作者 WANG Yi-guang GUO Zheng-chu 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第1期1-23,共23页
In the realm of large-scale machine learning,it is crucial to explore methods for reducing computational complexity and memory demands while maintaining generalization performance.Additionally,since the collected data... In the realm of large-scale machine learning,it is crucial to explore methods for reducing computational complexity and memory demands while maintaining generalization performance.Additionally,since the collected data may contain some sensitive information,it is also of great significance to study privacy-preserving machine learning algorithms.This paper focuses on the performance of the differentially private stochastic gradient descent(SGD)algorithm based on random features.To begin,the algorithm maps the original data into a lowdimensional space,thereby avoiding the traditional kernel method for large-scale data storage requirement.Subsequently,the algorithm iteratively optimizes parameters using the stochastic gradient descent approach.Lastly,the output perturbation mechanism is employed to introduce random noise,ensuring algorithmic privacy.We prove that the proposed algorithm satisfies the differential privacy while achieving fast convergence rates under some mild conditions. 展开更多
关键词 learning theory differential privacy stochastic gradient descent random features reproducing kernel Hilbert spaces
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Improved organs at risk segmentation based on modified U‐Net with self‐attention and consistency regularisation
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作者 Maksym Manko Anton Popov +1 位作者 Juan Manuel Gorriz Javier Ramirez 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第4期850-865,共16页
Cancer is one of the leading causes of death in the world,with radiotherapy as one of the treatment options.Radiotherapy planning starts with delineating the affected area from healthy organs,called organs at risk(OAR... Cancer is one of the leading causes of death in the world,with radiotherapy as one of the treatment options.Radiotherapy planning starts with delineating the affected area from healthy organs,called organs at risk(OAR).A new approach to automatic OAR seg-mentation in the chest cavity in Computed Tomography(CT)images is presented.The proposed approach is based on the modified U‐Net architecture with the ResNet‐34 encoder,which is the baseline adopted in this work.The new two‐branch CS‐SA U‐Net architecture is proposed,which consists of two parallel U‐Net models in which self‐attention blocks with cosine similarity as query‐key similarity function(CS‐SA)blocks are inserted between the encoder and decoder,which enabled the use of con-sistency regularisation.The proposed solution demonstrates state‐of‐the‐art performance for the problem of OAR segmentation in CT images on the publicly available SegTHOR benchmark dataset in terms of a Dice coefficient(oesophagus-0.8714,heart-0.9516,trachea-0.9286,aorta-0.9510)and Hausdorff distance(oesophagus-0.2541,heart-0.1514,trachea-0.1722,aorta-0.1114)and significantly outperforms the baseline.The current approach is demonstrated to be viable for improving the quality of OAR segmentation for radiotherapy planning. 展开更多
关键词 3‐D computer vision deep learning deep neural networks image segmentation medical image processing object segmentation
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Bioactive compounds in Hericium erinaceus and their biological properties:a review
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作者 Yue Qiu Genglan Lin +4 位作者 Weiming Liu Fuming Zhang Robert J.Linhardt Xingli Wang Anqiang Zhang 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第4期1825-1844,共20页
Hericium erinaceus is a nutritious edible and medicinal fungi,rich in a variety of functional active ingredients,with various physiological functions such as antioxidation,anticancer,and enhancing immunity.It is also ... Hericium erinaceus is a nutritious edible and medicinal fungi,rich in a variety of functional active ingredients,with various physiological functions such as antioxidation,anticancer,and enhancing immunity.It is also effective in protecting the digestive system and preventing neurodegenerative diseases.In this review paper,we summarize the sources,structures and efficacies of the main active components in H.erinaceus fruiting body,mycelium,and culture media,and update the latest research progress on their biological activities and the related molecular mechanisms.Based on this information,we provide detailed challenges in current research,industrialization and information on the active ingredients of H.erinaceus.Perspectives for future studies and new applications of H.erinaceus are proposed. 展开更多
关键词 Hericium erinaceus Bioactive compounds Biological activities ANTIOXIDATION NEUROPROTECTION IMMUNOREGULATION
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Thermosensitive and Wound-Healing Gelatin-Alginate Biopolymer Hydrogels Modified with Humic Acids
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作者 Denis Miroshnichenko Vladimir Lebedev +7 位作者 Katerina Lebedeva Anna Cherkashina Sergey Petrushenko Olena Bogoyavlenska Anzhela Olkhovska Ihor Hrubnyk Liudmyla Maloshtan Natalja Klochko 《Journal of Renewable Materials》 EI CAS 2024年第10期1691-1713,共23页
The main goal of the article is the creation and study of thermosensitive and wound-healing gelatin-alginate bio-polymer hydrogels modified with humic acids.Their rheological properties,swelling and contraction behavi... The main goal of the article is the creation and study of thermosensitive and wound-healing gelatin-alginate bio-polymer hydrogels modified with humic acids.Their rheological properties,swelling and contraction behavior were experimentally investigated,elucidated using Fourier transform infrared spectroscopy and used to achieve the physiological melting point,which is necessary for successful drug delivery.It has been shown that in the gelatin-alginate-humic acid biopolymer hydrogels systems,it is possible to obtain a gel-sol transition temperature close to the physiological temperature of 37℃,which is important for drug delivery in the treatment of wounds.By changing the type and concentration of humic acids in the gelatin-alginate hydrogel,it turned out to be achiev-able to regulate the softening time of the gel on the human body in the range from 6 to 20 min,which provides the possibility of controlled prolonged delivery of drugs.Based on the study of the influence of calcium ions on the properties of humic acids and ion exchange,as well as the interaction of humic acids,sodium alginate and gelatin with the formation of tighter gel networks,approaches to regulate the rate of softening of hydrogels at physiological temperature and their swelling,which simulates the absorption of exudate,were proposed and implemented.In addition,low shrinkage of the hydrogel surface due to cross-linking of gelatin-alginate networks when modified with humic acids was experimentally confirmed,which is important for avoiding problems of wound contracture and contour deformations when using dressings for wound healing.Thus,the developed opti-mized innovative biopolymer hydrogels synergistically combine the outstanding properties of natural molecular polymers and humic acids and are promising for the creation of effective medicines for wound healing. 展开更多
关键词 Gelatin-alginate hydrogel humic acids wound healing rheological properties swelling THERMOSENSITIVITY CONTRACTION
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Waste Mg alloys hydrogen production from seawater:An integrative overview of medium optimization,hydrogen-producing materials,underlying mechanisms,innovative technologies,and device development
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作者 Danting Li Xiaojiang Hou +6 位作者 Duode Zhao Chenlu Wang Xinlei Xie Xiaohui Ye Guang Yang Ping Hu Guangsheng Xu 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第9期3491-3515,共25页
In response to global carbon neutrality targets,there is an urgent need for large-scale,clean hydrogen production technologies to supplant fossil fuels and underpin the establishment of a‘hydrogen economy’.The prosp... In response to global carbon neutrality targets,there is an urgent need for large-scale,clean hydrogen production technologies to supplant fossil fuels and underpin the establishment of a‘hydrogen economy’.The prospect of large-scale on-site green hydrolysis of Mg-based materials for hydrogen production has attracted wide attention.Aiming at the problems of easy formation of inert oxide layer on its surface and the production of Mg(OH)_(2) to hinder the hydrolysis process,it is urgent to explore efficient,low-cost and green modification strategies.In this work,the green modification strategy for hydrolyzing hydrogen production of Mg-based materials was summarized,and the fast initial kinetics and high hydrogen production rate could be achieved by adjusting hydrolysis medium conditions and modifying Mg-based material.The significance of hydrolytic hydrogen production technology and device development for the realization of Mg-based hydrolytic hydrogen production was evaluated.Meanwhile,this work looks forward to the future direction of hydrogen production modification by hydrolysis of Mg-based alloy,and gradually optimizes the hydrolysis performance of industrial multi-component waste Mg alloy under the premise of green hydrogen production,and proposes the goal of efficient modification of waste Mg alloy,high-quality utilization of seawater,and low-cost and controllable hydrogen production process. 展开更多
关键词 Hydrogen energy Mg-based materials HYDROLYSIS Modification strategies Green technology
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Temporal and spatial differences in human activities performed in Urban Green Spaces of Vilnius(Lithuania)
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作者 Luís Valença Pinto Carla Sofia Santos Ferreira Paulo Pereira 《Geography and Sustainability》 CSCD 2024年第2期302-317,共16页
Urban green spaces(UGS)are relevant to city well-being,as recognized by the United Nations’Sustainable Development Goals(SDGs).However,few studies have studied the temporal use of UGS.This work assessed the seasonal,... Urban green spaces(UGS)are relevant to city well-being,as recognized by the United Nations’Sustainable Development Goals(SDGs).However,few studies have studied the temporal use of UGS.This work assessed the seasonal,weekly,and daily use of three urban green spaces(Vingis Park,Bernardino Garden,and Jomantas Park)in Vilnius(Lithuania).The study is based on an on-site observation-based survey,which recorded users’characteristics,activities,and weather conditions during summer and winter.The results showed that UGS’s seasonal,weekly,and daily use differed according to park and users’characteristics.Parks with a higher diversity of facilities had a high seasonal difference in the number of observed activities.User numbers were higher in the summer for activities with children,social activities,sports,and water activities than in the winter.Jomantas Park had the lowest variability in user characteristics.Weather variables were linked to changes in users’activities.Higher precipitation and lower temperature were associated with reducing the number of users and the diversity of registered activities.Most of the stationary activities were observed during summer.The diversity of the observed activities was associated with the available facilities rather than the park size.The distribution of stationary activities was spatially correlated with facility/equipment(benches,playgrounds,sports,and fitness equipment)and proximity to water features.The results of this study are relevant for UGS design,planning,and management. 展开更多
关键词 Urban parks Seasonal differences Temporal use Time of day Spatial distribution of UGS users
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正常和夹层升主动脉组织各层的生物力学和微观结构性质对比
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作者 郭小亚 孙浩亮 +1 位作者 Dalin Tang 王梁 《医用生物力学》 CAS CSCD 北大核心 2024年第S01期539-539,共1页
目的主动脉夹层疾病对主动脉血管壁各层的力学性质和微观结构的影响尚没有系统的研究。本文通过对比正常和发生A型夹层的人体升主动脉组织各层的力学性质和微观结构来探究该问题。方法从13例A型主动脉夹层患者和5例无主动脉疾病的供体... 目的主动脉夹层疾病对主动脉血管壁各层的力学性质和微观结构的影响尚没有系统的研究。本文通过对比正常和发生A型夹层的人体升主动脉组织各层的力学性质和微观结构来探究该问题。方法从13例A型主动脉夹层患者和5例无主动脉疾病的供体中共采集了18个升主动脉标本。对每个升主动脉标本进一步分解以获得3个组织样本:主动脉壁全层、内膜-中膜层和外膜层。对每个组织样本进行双轴拉伸测试获得实验应力拉伸比数据,采用Fung-Type材料模型对实验数据进行拟合并计算组织硬度。采用Elastin Van Gieson染色和Masson染色来量化组织中弹性纤维和胶原纤维密度。采用统计分析以确定夹层主动脉和正常主动脉组织各层的力学和微观结构性质是否存在显著差异。结果在拉伸比为1.30时,夹层组内膜-中膜层样本的硬度在长轴方向上显著高于正常组(P=0.0068),而在其他方向或其他层组织中没有发现显著差异。尽管两组之间的弹性纤维或胶原纤维密度没有显著差异,但夹层组的所有3个组织层的弹性纤维密度通常较低,但胶原纤维密度较高。结论与正常主动脉组织相比,夹层主动脉组织中内膜-中膜层的弹性纤维密度较低,而组织硬度却较高,表明内膜-中膜层组织硬度可能是主动脉夹层的潜在生物标志物。 展开更多
关键词 主动脉夹层 升主动脉 主动脉疾病 动脉血管壁 主动脉组织 主动脉壁 弹性纤维 胶原纤维
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Review on Lithium-ion Battery PHM from the Perspective of Key PHM Steps
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作者 Jinzhen Kong Jie Liu +4 位作者 Jingzhe Zhu Xi Zhang Kwok-Leung Tsui Zhike Peng Dong Wang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第4期1-22,共22页
Prognostics and health management(PHM)has gotten considerable attention in the background of Industry 4.0.Battery PHM contributes to the reliable and safe operation of electric devices.Nevertheless,relevant reviews ar... Prognostics and health management(PHM)has gotten considerable attention in the background of Industry 4.0.Battery PHM contributes to the reliable and safe operation of electric devices.Nevertheless,relevant reviews are still continuously updated over time.In this paper,we browsed extensive literature related to battery PHM from 2018to 2023 and summarized advances in battery PHM field,including battery testing and public datasets,fault diagnosis and prediction methods,health status estimation and health management methods.The last topic includes state of health estimation methods,remaining useful life prediction methods and predictive maintenance methods.Each of these categories is introduced and discussed in details.Based on this survey,we accordingly discuss challenges left to battery PHM,and provide future research opportunities.This research systematically reviews recent research about battery PHM from the perspective of key PHM steps and provide some valuable prospects for researchers and practitioners. 展开更多
关键词 Lithium-ion batteries Prognostics and health management Remaining useful life State of health Predictive maintenance
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Soil bacterial and fungal communities resilience to long-term nitrogen addition in subtropical forests in China
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作者 Xinlei Fu Yunze Dai +3 位作者 Jun Cui Pengfei Deng Wei Fan Xiaoniu Xu 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期95-108,共14页
Atmospheric nitrogen(N)deposition is predicted to increase,especially in the subtropics.However,the responses of soil microorganisms to long-term N addition at the molecular level in N-rich subtropical forests have no... Atmospheric nitrogen(N)deposition is predicted to increase,especially in the subtropics.However,the responses of soil microorganisms to long-term N addition at the molecular level in N-rich subtropical forests have not been clarified.A long-term nutrient addition experiment was conducted in a subtropical evergreen old-growth forest in China.The four treatments were:control,low N(50 kg N ha^(-1)a^(-1)),high N(100 kg N ha^(-1)a^(-1)),and combined N and phosphorus(P)(100 kg N ha^(-1)a^(-1)+50 kg P ha^(-1)a^(-1)).Metagenomic sequencing characterized diversity and composition of soil microbial communities and used to construct bacterial/fungal co-occurrence networks.Nutrient-treated soils were more acidic and had higher levels of dissolved organic carbon than controls.There were no significant differences in microbial diversity and community composition across treatments.The addition of nutrients increased the abundance of copiotrophic bacteria and potentially beneficial microorganisms(e.g.,Gemmatimonadetes,Chaetomium,and Aureobasidium).Low N addition increased microbiome network connectivity.Three rare fungi were identified as module hubs under nutrient addition,indicating that low abundance fungi were more sensitive to increased nutrients.The results indicate that the overall composition of microbial communities was stable but not static to long-term N addition.Our findings provide new insights that can aid predictions of the response of soil microbial communities to long-term N addition. 展开更多
关键词 Long-term nitrogen addition Old-growth subtropical forest METAGENOMICS Beneficial microorganisms Co-occurrence network
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基于在体OCT影像的冠脉斑块破裂风险的形态和力学评估
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作者 王梁 章晓国 +3 位作者 朱燕文 吕蕊 郭小亚 Dalin Tang 《医用生物力学》 CAS CSCD 北大核心 2024年第S01期59-60,共2页
目的仅根据冠状动脉斑块形态难以有效识别具有破裂倾向并导致临床重大不良事件的易损斑块。斑块生物力学与斑块破裂密切相关。如何利用这些力学信息对斑块破裂程度进行评估仍是一项重大挑战。方法获取了40名冠心病患者的冠脉斑块在体光... 目的仅根据冠状动脉斑块形态难以有效识别具有破裂倾向并导致临床重大不良事件的易损斑块。斑块生物力学与斑块破裂密切相关。如何利用这些力学信息对斑块破裂程度进行评估仍是一项重大挑战。方法获取了40名冠心病患者的冠脉斑块在体光学相干断层影像,并根据其斑块形态特征将斑块分为3组:20个稳定斑块、10个易损斑块和10个破裂斑块。对每个斑块进行有限元力学仿真,并提取斑块纤维帽和肩部区域的斑块应力峰值进行后续分析。基于斑块应力峰值提出斑块破裂风险的力学评估方案,从生物力学角度对3组斑块进行分组,并与形态学分组结果进行对比,计算两种分组的一致性。结果破裂和易损斑块的斑块应力峰值显著高于稳定斑块(P<0.0001和P=0.0007),而破裂和易损斑块之间没有发现显著差异(P=0.8538)。以150 k Pa和230 k Pa为斑块应力阈值建立了力学评估方案从而对斑块进行分组,对稳定斑块、易损斑块、破裂斑块的分组结果与形态学分组结果重合率分别为17/20、5/10和7/10。结论该斑块力学评估方案与形态学分组的高度一致性证明了其能有效评估冠脉斑块破裂风险的能力。特别对于稳定斑块,两种分组结果的高度一致表明结合斑块力学和形态可以可靠地识别仅具有稳定斑块的患者,以避免不必要的手术干预。 展开更多
关键词 易损斑块 冠心病患者 稳定斑块 生物力学 冠脉斑块 斑块破裂 纤维帽 力学仿真
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Fractional Gradient Descent RBFNN for Active Fault-Tolerant Control of Plant Protection UAVs
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作者 Lianghao Hua Jianfeng Zhang +1 位作者 Dejie Li Xiaobo Xi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第3期2129-2157,共29页
With the increasing prevalence of high-order systems in engineering applications, these systems often exhibitsignificant disturbances and can be challenging to model accurately. As a result, the active disturbance rej... With the increasing prevalence of high-order systems in engineering applications, these systems often exhibitsignificant disturbances and can be challenging to model accurately. As a result, the active disturbance rejectioncontroller (ADRC) has been widely applied in various fields. However, in controlling plant protection unmannedaerial vehicles (UAVs), which are typically large and subject to significant disturbances, load disturbances andthe possibility of multiple actuator faults during pesticide spraying pose significant challenges. To address theseissues, this paper proposes a novel fault-tolerant control method that combines a radial basis function neuralnetwork (RBFNN) with a second-order ADRC and leverages a fractional gradient descent (FGD) algorithm.We integrate the plant protection UAV model’s uncertain parameters, load disturbance parameters, and actuatorfault parameters and utilize the RBFNN for system parameter identification. The resulting ADRC exhibits loaddisturbance suppression and fault tolerance capabilities, and our proposed active fault-tolerant control law hasLyapunov stability implications. Experimental results obtained using a multi-rotor fault-tolerant test platformdemonstrate that the proposed method outperforms other control strategies regarding load disturbance suppressionand fault-tolerant performance. 展开更多
关键词 Radial basis function neural network plant protection unmanned aerial vehicle active disturbance rejection controller fractional gradient descent algorithm
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Simulation on dynamic characteristics of TC4 cutting with crack defects
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作者 SHI Lichen WANG Jian +1 位作者 DOU Weitao YUAN Jiageng 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2024年第3期387-396,共10页
Titanium alloys play an important role in aerospace and other fields.However,after precision forging and cold rolling process,some defects will appear on the subsurface of titanium alloy bars,thus reducing the surface... Titanium alloys play an important role in aerospace and other fields.However,after precision forging and cold rolling process,some defects will appear on the subsurface of titanium alloy bars,thus reducing the surface quality and precision of turning process.This study aimed at exploring the effect of crack defects on TC4 cutting.Firstly,the finite element cutting simulation model of TC4 material with crack defects was established in ABAQUS.Then,the cutting parameters such as cutting force,stress concentration,chip morphology,residual stress were obtained by changing the variables such as the size and height of crack defects.Finally,the turning experiment was carried out on centerless lathe.The results show that the cutting force changes abruptly when the defect position is located on the cutting path,the maximal stress occurs at the tip of the defect,and the mutation of stress value is more serious with the increase of defect size;the buckling deformation of chip morphology occurs and becomes less serious with the increase of the distance between the defect position and the workpiece surface;the surface residual stress near the defect is related to the stress when the tool is close to the defect,the larger defect size and the closer to the machined surface,the greater the residual stress.Therefore,under certain processing conditions,the TC4 material should avoid large size defects or increase the distance between defects and the machined surface,so as to obtain better and stable surface quality. 展开更多
关键词 crack defect TC4 ABAQUS centerless lathe
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Biology of Flowering of Some Species of the Genus Phlomoides Moench
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作者 Mukaddas Kholbutayeva Khislat Khaydarov +1 位作者 Nodira Nurullayeva Abdurakhmonova Ezoza Kakhramon Kizi 《American Journal of Plant Sciences》 CAS 2024年第4期268-273,共6页
The article presents the biology of flowering and the daily dynamics of flowering of two species from the Lamiaceae family: ph. anisochila va ph. sogdiana of the distribution out in the Nuratau Mountains range.
关键词 Phlomoides Rare and Endemic Species Nurata Mountain Systems Flowering Dynamics Abiotic Factors CENOPOPULATION
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Feasibility of Transferring Drinking Water from the Senegal River in the East (Backel) to the West Center (Fatick) in Senegal
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作者 Ndiouga Camara Alioune Ly +1 位作者 Babacar Diouf Séni Tamba 《Journal of Water Resource and Protection》 CAS 2024年第11期720-729,共10页
Every year, 24 billion m3 of fresh water are thrown into the sea by the Senegal River, while most of the country’s populations do not have permanent access to drinking water. Also, agricultural land, which extends as... Every year, 24 billion m3 of fresh water are thrown into the sea by the Senegal River, while most of the country’s populations do not have permanent access to drinking water. Also, agricultural land, which extends as far as the eye can see, is only used during winter periods, thus slowing down the development of agriculture. It is in this context that this article studies the feasibility of transferring drinking water from the Senegal River in the east of the country to the center-west through a transfer canal to meet the drinking water needs of the populations. In addition, we intend to flood the fossil valleys from this canal and recharge the aquifers. The watershed resulting from the juxtaposition of the two watersheds which dominate central Senegal has a slightly descending profile from Bakel to Fatick. This promotes gravity flow of water over 542 km. This analysis is carried out by the Glabal Mapper software and SRTM1 images. We report that all water needs have been estimated at approximately 70 m3/s based on the ANDS census in 2023, the distribution of arable land and groundwater recharge areas in the country. The waters flowing in the canal have depths (draft) not reaching 4.6 m. These results are obtained by applying the Manning Strickler equation, on a channel with a straight cross-section in the shape of a trapezoid and lined with sand concrete. The canal thus designed will bring water to populations and arid zones in the central and central-western regions of the country where problems persist. However, it will be necessary to overcome a difference in altitude of 96 m over 30 km to raise the water from the river to the threshold of the canal in order to ensure the flow in the latter. We have retained two calculation variants (Canal + Pumping or Single Pumping) whose pumping stations will be powered by solar fields. Due to the heavy investments, the installations upstream of the canal will be modular over time. Consequently, the central canal project will be constructed in six (6) phases of ten (10) years. 展开更多
关键词 Fresh Water CANAL Fossil Valleys Aquifers The Dividing Line Watersheds Gravity Flow Sand Concrete Height Difference Modular Solar Fields
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Characterization of Wastewater in School Environments for an Ecological Treatment Solution: A Case Study of Ndiebene Gandiol 1 School
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作者 Falilou Coundoul Abdou Khafor Ndiaye Abdoulaye Deme 《Journal of Water Resource and Protection》 CAS 2024年第1期27-40,共14页
The study conducted at Ndiebene Gandiol 1 school in Senegal has unveiled serious environmental and public health challenges. The wastewater analysis revealed high levels of Biochemical Oxygen Demand (BOD5), Chemical O... The study conducted at Ndiebene Gandiol 1 school in Senegal has unveiled serious environmental and public health challenges. The wastewater analysis revealed high levels of Biochemical Oxygen Demand (BOD5), Chemical Oxygen Demand (COD), and fecal coliforms, signaling potential risks to the well-being of students and staff. This situation mirrors a wider issue in rural educational settings, where inadequate sanitation persists. Intensive wastewater treatment options are known for their effectiveness against high pollutant loads but are resource-intensive in both energy and cost. Conversely, extensive treatment systems, while requiring more land, provide a sustainable alternative by harnessing natural processes for pollutant removal. The research suggests a hybrid treatment approach could serve the school’s needs, balancing the robust capabilities of intensive methods with the ecological benefits of extensive systems. Such a solution would need to be tailored to the specific environmental, financial, and logistical context of the school, based on comprehensive feasibility studies and stakeholder engagement. This study’s findings underscore the urgency of addressing sanitation in schools, as it is intrinsically linked to the health and academic success of students. Quick, effective, and long-term strategies are vital to secure a healthier and more prosperous future for the youth. With proper implementation, the school can transform its sanitation facilities, setting a precedent for rural educational institutions in Senegal and similar contexts globally. 展开更多
关键词 Wastewater Characterization Ecological Treatment School Sanitation PHYTOREMEDIATION Rural Infrastructure Environmental Health
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Photothermal self-healing polyurethane coating based on hollow nanofillers in seawater
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作者 KANG Qian-qian MAO Zhi-peng +3 位作者 PENG Li-ming MYRONYUK Oleksiy LI Wei-hua WANG Wei 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第10期3447-3462,共16页
Herein,a novel composite coating with excellent self-healing and corrosion resistance activated byphotothermal responsive hollow core-shell nanofillers was developed.A photothermal nanofiller(Co_(9)S_(8)@Bi_(2)S_(3))w... Herein,a novel composite coating with excellent self-healing and corrosion resistance activated byphotothermal responsive hollow core-shell nanofillers was developed.A photothermal nanofiller(Co_(9)S_(8)@Bi_(2)S_(3))with ahollow core-shell structure was synthesized and then added to polyurethane(PU)to prepare PU-Co_(9)S_(8)@Bi_(2)S_(3)compositecoating.Applying 808 nm near-infrared irradiation induces a photothermal effect in Co_(9)S_(8)@Bi_(2)S_(3),which subsequentlyinitiates the reconstruction of reversible hydrogen bonds,facilitating the self-healing of coating scratches.The excellentphotothermal self-healing performance of PU-Co_(9)S_(8)@Bi_(2)S_(3)coating was demonstrated by scratch tests and moleculardynamics simulations.The electrochemical impedance spectroscopy test results showed that the PU-Co_(9)S_(8)@Bi_(2)S_(3)coating has good self-healing and anti-corrosion properties.The low-frequency impedance modulus of the coating afterthree self-healing sessions was still close to 109Ω·cm^(2)after 30 d of immersion in seawater.This study provides a newstrategy for developing multi-cycle self-healing coatings triggered by photothermal effects. 展开更多
关键词 polyurethane coating photothermal effect SELF-HEALING corrosion protection
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Design and Sizing of an Ecological Wastewater Treatment System in a School Environment: A Case Study of Ndiebene Gandiol 1 School
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作者 Falilou Coundoul Abdou Khafor Ndiaye +1 位作者 Abdoulaye Deme David de la Varga 《Journal of Water Resource and Protection》 CAS 2024年第1期41-57,共17页
The primary objective of this study was to design and size a sustainable sanitation solution for the Ndiebene Gandiol 1 school located in the eponymous commune in northern Senegal. Field investigations led to the coll... The primary objective of this study was to design and size a sustainable sanitation solution for the Ndiebene Gandiol 1 school located in the eponymous commune in northern Senegal. Field investigations led to the collection of wastewater samples. Their analysis revealed specific pollutant loads, including loads of BOD5 3.6966 kgO<sub>2</sub>/day and COD of 12.8775 kgO<sub>2</sub>/day, which were central to the design phase. Following a rigorous assessment of the existing sanitation infrastructure, constructed wetland (CWs) emerged as the most appropriate ecological solution. This system, valued for its ability to effectively remove contaminants, was tailored to the specific needs of the site. Consequently, the final design of the filter extends over 217.16 m<sup>2</sup>, divided into two cells of 108.58 m<sup>2</sup> each, with dimensions of 12.77 m in length and 8.5 m in width. The depth of the filtering medium is approximately 0.60 m, meeting the standards while ensuring maximized purification. Typha, an indigenous and prolific plant known for its purification abilities, was selected as the filtering agent. Concurrently, non-crushed gravel was chosen for its proven filtration capacity. This study is the result of a combination of scientific rigor and design expertise. It provides a holistic view of sanitation for Ndiebene Gandiol. The technical specifications and dimensions of the constructed wetland filter embody an approach that marries indepth analysis and practical application, all aimed at delivering an effective and long-lasting solution to the local sanitation challenges. By integrating precise scientific data with sanitation design expertise, this study delivers a holistic solution for Ndiebene Gandiol. The detailed dimensions and specifications of the constructed wetland filter reflect a methodology that combines meticulous analysis with practical adaptation, aiming to provide an effective and sustainable response to the challenges of rural and school sanitation in the northern region of Senegal. 展开更多
关键词 Water Review Hydraulic Engineering Water Treatment Agricultural Irrigation SANITATION Engineering Environment
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Characterization of squash polysaccharide and the anti-diabetic effect on type 2 diabetic rat revealed by urine metabolomics analysis
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作者 Li Liang Fuming Zhang +3 位作者 Quanhong Li Baoguo Sun Yuyu Zhang Robert J.Linhardt 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2937-2946,共10页
The present study reports the structural characteristics of 3 polysaccharide fractions(SPS-F1,SPS-F2 and SPS-F3)isolated and purified from squash.SPS-F1(molecular weight(Mw)=12.30 kDa)and SPS-F2(Mw=19.40 kDa)were like... The present study reports the structural characteristics of 3 polysaccharide fractions(SPS-F1,SPS-F2 and SPS-F3)isolated and purified from squash.SPS-F1(molecular weight(Mw)=12.30 kDa)and SPS-F2(Mw=19.40 kDa)were likely to contain HG and RG-I domain of pectic polysaccharide,respectively.SPS-F2(Mw=270.4 kDa)was mainly composed of rhamnose,galactose and arabinose.The treatment with SPS decreased body weight gain,glucose and TG levels in type 2 diabetes rats.Besides,25 differential metabolites were identified based on urinary metabolomics analysis,which are crucial to the anti-diabetic effect of SPS.The regulation of nicotinamide N-oxide,histamine,cis-aconitate,citrate,L-malic acid,3-(3-hydroxyphenyl)propanoic acid and N-acetyl-L-aspartic acid were mainly associated with energy metabolism,gut microbiota and inflammation.Study of surface plasmon resonance revealed the binding kinetics with galectin-3(Gal-3)and fibroblast growth factor 2(FGF2).The K_(D)values of SPS-F2 and SPS-F3 to Gal-3 were 4.97×10^(-3)and 1.48×10^(-3)mol/L,indicating a weak binding affinity.All 3 fractions showed moderate binding to FGF2 and the affinity was SPS-F3>SPS-F2>SPS-F1.Thus,the metabolomics and SPR approach were proved to be a promising tool in exploring the anti-diabetes effects of SPS and provided a deep understanding of the mechanisms. 展开更多
关键词 POLYSACCHARIDE Metabolomics Type 2 diabetes Surface plasmon resonance
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