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Self-dispersed molybdenum disulfide quantum dot/graphene crumpled ball as efficient high temperature lubricant additive

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Friction 2024年第8期12卷 1771-1784页

作者： Guiru DU Yujuan ZHANG Shuguang FAN Ningning SONG Shengmao ZHANG Pingyu ZHANG Engineering research center for Nanomaterials Henan UniversityKaifeng 475004China

Inorganic nanoparticles have been proved as powerful lubricant additives at elevated ***,the tribological properties are inevitably impaired due to poor dispersion and insufficient high temperature resistance of organic matter modified ***,we prepare a self-dispersed molybdenum disulfide quantum dot/graphene crumpled ball(MGCB)comprising molybdenum disulfide quantum dot uniformly interspersed on the wrinkled graphene *** crumpled ball composite possesses excellent dispersity in polyalkylene glycol base oil without depending on surface *** with the conventional phosphate esters lubricant,our results indicate MGCB could vastly improve the lubrication performance of polyalkylene glycol with an extremely low concentration(0.05 wt%)at elevated temperature(150°C),showing a friction reduction of 47%and a wear reduction of 3.%compared with the conventional phosphate esters lubricant(tricresyl phosphate,TCP).This is because crumpled ball potentiates synergistic lubrication effect within the boundary ***,we envision our designed self-dispersed MGCB has significant potential in tribological application at elevated temperature.

关键词： self-dispersed crumpled ball graphene molybdenum disulfide quantum dot high temperature tribological properties

Satellite anomaly detection based on reconstruction discrepancy theory utilizing a new dual-branch reconstruction model

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Science China Technological Sciences 2024年第10期67卷 3294-3307页

作者： ZHAO HaoTian QIU Shi LIU Ming CAO XiBin research center of Satellite Technology School of AstronauticsHarbin Institute of Technology

To enhance the accuracy of deep learning methods based on reconstruction discrepancy in satellite anomaly detection tasks, this study proposes a dual-branch reconstruction model(DBRM) and designs a comprehensive satellite anomaly detection framework around this model. Firstly, we introduce the temporal-channel mixer(TC-Mixer) module, which mainly comprises a self-attention layer for capturing long-range temporal dependencies in telemetry data, and two types of feed-forward networks(FFN) for extracting complex patterns in the temporal and channel dimension of telemetry data. This design endows the TC-Mixer module with robust capabilities for extracting complicated dependencies in telemetry data. Secondly, with the TC-Mixer module as the main component, we designed the DBRM. This model utilizes a shared latent representation layer, allowing the regeneration branch and forecasting branch of the DBRM to share most of the feature extraction network architecture. This approach significantly enhances the model's regression accuracy while reducing computational complexity. Thirdly, using the DBRM as the core network model, we devised a comprehensive satellite anomaly detection framework. This includes an anomaly criterion that considers the reconstruction discrepancy of both the regeneration and forecasting branches, the peak-over-threshold(POT) method for anomaly thresholding, and the MIC-based feature engineering method, etc. Finally, we conducted comparative experiments with several SOTA anomaly detection algorithms on two public and one private satellite anomaly detection datasets. The experimental results validate the effectiveness and superiority of our proposed method.

关键词： anomaly detection reconstruction discrepancy dual-branch reconstruction model (DBRM) satellite telemetry data time series

Movement Trend Alterations in the Periaqueductal Gray(PAG)-Employed Ratbot Navigation Are Correlated with Stimulation Parameters

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Journal of Bionic Engineering 2024年第2期21卷 866-876页

作者： Sina Khajei Abed Khorasani Mohammad Reza Afarinesh Vahid Sheibani Neuroscience research center Institute of NeuropharmacologyKerman University of Medical SciencesKerman***Iran Cognitive Neuroscience research center Institute of NeuropharmacologyKerman University of Medical SciencesKerman***Iran

In previous studies,Periaqueductal Gray(PAG)stimulation was used to stop ratbots from *** to the homology between the PAG and the intercollicular nucleus,which has been used for forward movement in birds,we investigated the possibility of PAG application to induce forward locomotion for the first *** a corridor maze,the traveled distances via PAG electrical stimulation were examined in nine Wistar male rats during three sessions.A custom-designed stimulator was developed to apply the *** results showed reductions in responses to stimulation over ***,the traveled distances had negative slopes during the consecutive trials(in 8 out of the 9 rats),and the slope mean was significantly different from *** was a strong correlation between the stimulation parameters(electric Charge per Phase(CPP)and the Number of Pulses(NP))and the observed *** negative Movement Slopes(MS)were highly correlated with the CPP and the NP,as the Pearson's linear correlation coefficients were−0.87 and−0.79,*** MS-CPP coefficients of determination(R-squared)were also between 0.76 and *** addition,the MS-NP coefficients of determination were between 0.63.and ***,it is concluded that the electrical stimulation parameters influence the behavioral outcomes ***,the PAG area may be considered a suitable candidate for forward locomotion control in the future if the area is harnessed effectively to prevent undesirable chaotic behaviors.

关键词： Periaqueductal Gray(PAG) Navigation Ratbot Animal-robot Forward locomotion Movement slope

Time-sensitive prediction of NO_(2) concentration in China using an ensemble machine learning model from multi-source data

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Journal of Environmental Sciences 2024年第3期137卷 30-40页

作者： Chenliang Tao Man Jia Guoqiang Wang Yuqiang Zhang Qingzhu Zhang Xianfeng Wang Qiao Wang Wenxing Wang Big Data research center for Ecology and Environment Environment Research InstituteShandong UniversityQingdao 266237China Shandong Provincial Eco-environment Monitoring center Jinan 250101China

Nitrogen dioxide(NO_(2))poses a critical potential risk to environmental quality and public health.A reliable machine learning(ML)forecasting framework will be useful to provide valuable information to support government *** on the data from1609 air quality monitors across China from 2014-2020,this study designed an ensemble ML model by integrating multiple types of spatial-temporal variables and three sub-models for time-sensitive prediction over a wide *** ensemble ML model incorporates a residual connection to the gated recurrent unit(GRU)network and adopts the advantage of Transformer,extreme gradient boosting(XGBoost)and GRU with residual connection network,resulting in a 4.1%±1.0%lower root mean square error over XGBoost for the test *** ensemble model shows great prediction performance,with coefficient of determination of 0.91,0.86,and 0.77 for 1-hr,3.hr,and 24-hr averages for the test results,*** particular,this model has achieved excellent performance with low spatial uncertainty in Central,East,and North China,the major site-dense *** the interpretability analysis based on the Shapley value for different temporal resolutions,we found that the contribution of atmospheric chemical processes is more important for hourly predictions compared with the daily scale predictions,while the impact of meteorological conditions would be ever-prominent for the *** with existing models for different spatiotemporal scales,the present model can be implemented at any air quality monitoring station across China to facilitate achieving rapid and dependable forecast of NO_(2),which will help developing effective control policies.

关键词： Air quality prediction Deep learning Ensemble method Nitrogen dioxide Spatiotemporal covariates

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High-power all-polarization-maintaining fiber femtosecond pulse laser at 780 nm and its engineering integration

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中国激光 2024年

作者：罗韬温俊鹏王文龙李梓晗朱喆杨家豪吴垠修昊范怡衡刘亚龙韦小明杨中民 Guangzhou Yangming Laser Technology Co. Ltd 3. Research Institute of Future Technology South China Normal University School of Physics and Optoelectronics State Key Laboratory of Luminescent Materials and Devices Guangdong Engineering Technology Research and Development Center of Special Optical Fiber Materials and Device Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques South China University of Technology

We present a high-power, high-stability all-polarization-maintaining (all-PM)fiber femtosecond pulse laser source at 780 nm with full engineering integration that comprises an all-PM fiber amplified chirped pulse laser at 1560 nm, a grating pair compressorandasecond-harmonicgeneration(SHG)***-PMfiber amplified chirped pulse laser at 1560 nm operates with a repetition rate of 111.5 MHz and an average power of 5.3. W, which is compressed with a pulse width of～204 *** 780-nm pulses are subsequently generated by SHG in a frequency-doubling *** achieve an average power of 2.22 W at 780 nm with a pulse width of 288 fs, an SHG efficiency of 52%, and a root-mean-square power fluctuation of 0.23., which is *** integrated for practical application with reliable laser operation. We anticipate that this780-nmall-PMfiberfemtosecondpulselaserwithfullengineeringintegrationis promising for frontier applications, like two-photon imaging, nanofabrication, terahertz generation, etc.

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Control of electromechanical performance in 3. printing latticestructured BaTiO_(3. piezoelectric ceramics

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Journal of Advanced Ceramics 2024年第7期13卷 987-1001页

作者： Zhujun Jiang Yinghong Sun Jimin Chen Yong Zeng Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing 100124China Beijing Engineering research center of 3. Printing for Digital Medical Health Beijing University of TechnologyBeijing 100124China

Barium titanate(BaTiO_(3.)piezoelectric ceramics with triply periodic minimal surface(TPMS)structures have been frequently used in filters,engines,artificial bones,and other fields due to their high specific surface area,high thermal stability,and good heat ***,only a limited number of studies have analyzed the effect of various parameters,such as different wall thicknesses and porosities of TPMS structures,on ceramic electromechanical *** this study,we first employed vat photopolymerization(VPP)three-dimensional(3.)printing technology to fabricate high-performance BaTiO_(3. *** investigated the slurry composition design and forming process and designed a stepwise sintering postprocessing technique to achieve a density of 96.3.and a compressive strength of 250±25 MPa,with the piezoelectric coefficient(d_(3.))reaching 263.pC/***,we explored the influence of three TPMS structures,namely,diamond,gyroid,and Schwarz P,on the piezoelectric and mechanical properties of BaTiO_(3. ceramics,with the gyroid structure identified as exhibiting optimal ***,we examined the piezoelectric and mechanical properties of BaTiO_(3. ceramics with the gyroid structure of varying wall thicknesses and porosities,thus enabling the modulation of ceramic electromechanical performance.

关键词： three-dimensional(3.)printing piezoelectric ceramics porous structure mechanical properties electrical properties

Liberica coffee as an alternative cropping system for sustainable farming on Indonesian Peatlands

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 180-188页

作者： Bariot Hafif Yulius Ferry Budi Martono Rita Harni Kurnia Dewi Sasmita Busyra B.Saidi Maswar Maswar R.Bambang Heryanto Novizar Nazir Fahmuddin Agus Meynarti Sari Dewi Ibrahim National research and Innovation Agency Research Center for Estate CropsIndonesia National research and Innovation Agency Research Center for Food CropsIndonesia Faculty of Agricultural Technology Andalas UniversityIndonesia

Indonesian peatlands are a fragile ecosystem,and to protect it,growing Liberica coffee is a promising way for both the environment and the *** study aimed to evaluate the performance of the liberica coffee on peatland with different water tables and develop an improved cultivation system in this *** study area was in Tanjung Jabung Barat District,Jambi Province,*** plant age is greater than 15 years and the average plant density was about 1000 trees/*** study was conducted in two *** 1st stage was a survey to identify and characterize smallholder liberica coffee farming at three peatland zones,namely 0-100 m,200-3.0 m,and>400 m from the principal drainage canal,and the 2nd stage was a field experiment to test the effectiveness of amendments in improving liberica coffee growth and improving degraded *** treatments were arranged in a randomized complete block design with four replications,including manure(M),at the rate of 10 t/hm^(2);lime(L),3.t/hm^(2);peat surface elevation(P),and a farmer’s practice(Control)without manure and/or lime as a *** research revealed that liberica coffee can not tolerate high water table as it may stimulate disease incidence and cause low-quality ***,recycling of organic C of about 17.14 t/(hm^(2)·a)through cherry residue application and litter compensated part of the loss of organic C through CO_(2)emissions,coffee bean removal,and maintaining peat fertility for sustainable *** low yield of(0.70±0.12)t/(hm^(2)∙a)coffee bean could be increased to(0.87±0.24)and(0.94±0.14)t/(hm^(2)∙a)by adding 3.t/(hm^(2)∙3.)of lime or 10 t/(hm^(2)∙a)of manure,*** research revealed that water table management and amendments are two main factors in liberica coffee farming on *** is of great significance to study the cultivation technology of coffee in peatland.

关键词： degraded peat amendments water table cultivation system liberica coffee alternative cropping system sustainable farming Indonesian Peatlands

Developing a fluorescence substrate for HRP-based diagnostic assays with superiorities over the commercial ADHP

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Chinese Chemical Letters 2024年第6期35卷 439-444页

作者： Zhichao Zhou Fuqian Chen Xiaotong Xia Dong Ye Rong Zhou Lei Li Tao Deng Zhenhua Ding Fang Liu Department of Radiation Medicine Guangdong Provincial Key Laboratory of Tropical Disease ResearchSchool of Public HealthSouthern Medical UniversityGuangzhou 510515China School of Pharmaceutical Sciences Guangzhou University of Chinese MedicineGuangzhou 510006China artemisinin research center Guangzhou University of Chinese MedicineGuangzhou 510006China State Key Laboratory of Respiratory Disease the First Affiliated Hospital of Guangzhou Medical UniversityGuangzhou Medical UniversityGuangzhou 510120China Guangzhou Laboratory Bio-IslandGuangzhou 510030China Nanshan Pharmaceutical Innovation research Institute of Guangdong Province Foshan 528225China

The combination of horseradish peroxidase(HRP)and a fluorescence substrate has been attracting great interests in developing sensitive biochemical analysis and immunoassays.10-Acetyl-3.7-dihydroxyphenoxazine(ADHP or Amplex red)is the most sensitive fluorogenic substrate known for HRP in current market,however,it suffers from some drawbacks,such as non-specific reactivity to carboxylesterase and limited fluorescence *** the present study,a novel HRP substrate10-cyclopropylcarbonyl-dichloro-dihydroxyphenoxazine(AR-2),has been prepared,which exhibited improved sensitivity than ADHP in sensing ***,the fluorescence of AR-2/HRP demonstrated improved tolerance to physiological relevant p H fluctuation as compared to ADHP/*** detection of uric acid/urate oxidase reaction indicated excellent application prospect of AR-2/HRP for monitoring H_(2)O_(2)-generating biochemical *** interestingly,an enzyme-linked immunosorbent assay(ELISA)using AR-2 as the fluorescence reporter has been successfully used in detecting IgG against severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)from human serum ***,AR-2 exhibits improved performances over the commercial ADHP,which will be an ideal alternative to ADHP in HRP-based fluorescence biochemical analysis and immunoassays.

关键词： Fluorescence immunoassay HRP fluorescence substrate Hydroresorufin Amplex red/ADHP SARS-CoV-2

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Lattice Boltzmann simulation study of anode degradation in solid oxide fuel cells during the initial aging process

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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 405-411页

作者： Shixue Liu Zhijing Liu Shuxing Zhang Hao Wu Hydrogen Energy Industrial Technology Innovation center China Nuclear Power Technology Research InstituteShenzhen 518031China Shenzhen Engineering research center for Hydrogen Safety Shenzhen 518031China

For present solid oxide fuel cells(SOFCs),rapid performance degradation is observed in the initial aging process,and the dis-cussion of the degradation mechanism necessitates quantitative ***,focused ion beam-scanning electron microscopy was em-ployed to characterize and reconstruct the ceramic microstructures of SOFC *** lattice Boltzmann method(LBM)simulation of multiphysical and electrochemical processes in the reconstructed models was *** samples collected from industrial-size cells were characterized,including a reduced reference cell and a cell with an initial aging *** parameters of the reconstructed microstructures revealed a significant decrease in the active triple-phase boundary and Ni connectivity in the aged cell compared with the reference *** LBM simulation revealed that activity degradation is dominant compared with microstructural degradation during the initial aging process,and the electrochemical reactions spread to the support layer in the aged *** microstructural and activity de-gradations are attributed to Ni migration and coarsening.

关键词： solid oxide fuel cell anode degradation focused ion beam-scanning electron microscopy lattice Boltzmann method

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