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Heterogeneous Cu_(x)O Nano‑Skeletons from Waste Electronics for Enhanced Glucose Detection
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作者 Yexin Pan Ruohan Yu +8 位作者 Yalong Jiang Haosong Zhong Qiaoyaxiao Yuan Connie Kong Wai Lee Rongliang Yang siyu chen Yi chen Wing Yan Poon Mitch Guijun Li 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第11期554-568,共15页
Electronic waste(e-waste)and diabetes are global challenges to modern societies.However,solving these two challenges together has been challenging until now.Herein,we propose a laser-induced transfer method to fabrica... Electronic waste(e-waste)and diabetes are global challenges to modern societies.However,solving these two challenges together has been challenging until now.Herein,we propose a laser-induced transfer method to fabricate portable glucose sensors by recycling copper from e-waste.We bring up a laser-induced full-automatic fabrication method for synthesizing continuous heterogeneous Cu_(x)O(h-Cu_(x)O)nano-skeletons electrode for glucose sensing,offering rapid(<1 min),clean,air-compatible,and continuous fabrication,applicable to a wide range of Cu-containing substrates.Leveraging this approach,h-Cu_(x)O nanoskeletons,with an inner core predominantly composed of Cu_(2)O with lower oxygen content,juxtaposed with an outer layer rich in amorphous Cu_(x)O(a-Cu_(x)O)with higher oxygen content,are derived from discarded printed circuit boards.When employed in glucose detection,the h-Cu_(x)O nano-skeletons undergo a structural evolution process,transitioning into rigid Cu_(2)O@CuO nano-skeletons prompted by electrochemical activation.This transformation yields exceptional glucose-sensing performance(sensitivity:9.893 mA mM^(-1) cm^(-2);detection limit:0.34μM),outperforming most previously reported glucose sensors.Density functional theory analysis elucidates that the heterogeneous structure facilitates gluconolactone desorption.This glucose detection device has also been downsized to optimize its scalability and portability for convenient integration into people’s everyday lives. 展开更多
关键词 Copper oxide Electron 3D tomography E-WASTE Glucose detection Electrochemical activation
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A New Merged Product Reveals Precipitation Features over Drylands in China
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作者 Min LUO Yuzhi LIU +5 位作者 Jie GAO Run LUO Jinxia ZHANG Ziyuan TAN siyu chen Khan ALAM 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第10期2079-2091,共13页
Due to the considerable uncertainties inherent in the datasets describing the spatiotemporal distributions of precipitation in the drylands of China,this study presents a new merged monthly precipitation product with ... Due to the considerable uncertainties inherent in the datasets describing the spatiotemporal distributions of precipitation in the drylands of China,this study presents a new merged monthly precipitation product with a spatial resolution of approximately 0.2°×0.2°during 1980–2019.The newly developed precipitation product was validated at different temporal scales(e.g.,monthly,seasonally,and annually).The results show that the new product consistently aligns with the spatiotemporal distributions reported by the Chinese Meteorological Administration Land Data Assimilation System(CLDAS)product and Multi-Source Weighted Ensemble Precipitation(MSWEP).The merged product exhibits exceptional quality in describing the drylands of China,with a bias of–2.19 mm month^(–1)relative to MSWEP.In addition,the annual trend of the merged product(0.09 mm month^(–1)yr^(−1))also closely aligns with that of the MSWEP(0.11 mm month^(–1)yr^(−1))during 1980–2019.The increasing trend indicates that the water cycle and wetting process intensified in the drylands of China during this period.In particular,there was an increase in wetting during the period from 2001–2019.Generally,the merged product exhibits potential value for improving our understanding of the climate and water cycle in the drylands of China. 展开更多
关键词 PRECIPITATION merged dataset DRYLANDS water cycle
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Mongolia Contributed More than 42%of the Dust Concentrations in Northern China in March and April 2023 被引量:6
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作者 siyu chen Dan ZHAO +8 位作者 Jianping HUANG Jiaqi HE Yu chen Junyan chen Hongru BI Gaotong LOU Shikang DU Yue ZHANG Fan YANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第9期1549-1557,共9页
Dust storms are one of the most frequent meteorological disasters in China,endangering agricultural production,transportation,air quality,and the safety of people’s lives and property.Against the backdrop of climate ... Dust storms are one of the most frequent meteorological disasters in China,endangering agricultural production,transportation,air quality,and the safety of people’s lives and property.Against the backdrop of climate change,Mongolia’s contribution to China’s dust cannot be ignored in recent years.In this study,we used the Weather Research and Forecasting model coupled with Chemistry(WRF-Chem),along with dynamic dust sources and the HYSPLIT model,to analyze the contributions of different dust sources to dust concentrations in northern China in March and April 2023.The results show that the frequency of dust storms in 2023 was the highest observed in the past decade.Mongolia and the Taklimakan Desert were identified as two main dust sources contributing to northern China.Specifically,Mongolia contributed more than 42%of dust,while the Taklimakan Desert accounted for 26%.A cold high-pressure center,a cold front,and a Mongolian cyclone resulted in the transport of dust aerosols from Mongolia and the Taklimakan Desert to northern China,where they affected most parts of the region.Moreover,two machine learning methods[the XGBoost algorithm and the Synthetic Minority Oversampling Technique(SMOTE)]were used to forecast the dust storms in March 2023,based on ground observations and WRF-Chem simulations over East Asia.XGBoost-SMOTE performed well in predicting hourly PM10 concentrations in China in March 2023,with a mean absolute error of 33.8μg m−3 and RMSE of 54.2μg m−3. 展开更多
关键词 dust aerosol Mongolian dust transboundary contribution WRF-Chem HYSPLIT model
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丝状真菌Podospora anserina AA11家族裂解多糖单加氧酶基因的鉴定和功能研究 被引量:2
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作者 杜文珍 李元敬 +4 位作者 吴佳玲 陈思羽 姜亮 刘刚 谢宁 《遗传》 CAS CSCD 北大核心 2023年第12期1128-1146,共19页
辅助活性蛋白家族(auxiliary activity family,AA family)中的裂解多糖单加氧酶(lytic polysaccharide monooxygenase,LPMO)能催化纤维素、几丁质和淀粉等多种难降解碳水化合物的氧化解聚。尽管目前对LPMO的酶学研究较多,但对LPMO基因... 辅助活性蛋白家族(auxiliary activity family,AA family)中的裂解多糖单加氧酶(lytic polysaccharide monooxygenase,LPMO)能催化纤维素、几丁质和淀粉等多种难降解碳水化合物的氧化解聚。尽管目前对LPMO的酶学研究较多,但对LPMO基因失活的研究却鲜有报道。本研究利用同源重组方法定点敲除丝状真菌Podospora anserina中AA11家族的5个LPMO基因PaLPMO11A(Pa_4_4790)、PaLPMO11B(Pa_1_5310)、PaLPMO11C(Pa_2_7840)、PaLPMO11D(Pa_2_8610)和PaLPMO11E(Pa_3_9420),分别构建了单突变体ΔPaLPMO11A(ΔA)、ΔPaLPMO11B(ΔB)、ΔPaLPMO11C(ΔC)、ΔPaLPMO11D(ΔD)和ΔPaLPMO11E(ΔE),然后通过遗传杂交构建所有多基因突变体。通过在不同碳源培养基上的表型分析、DAB和NBT染色以及纤维素酶活测定分析野生型菌株与突变型菌株在生长速率、有性生殖、氧化应激和纤维素降解能力等方面的差异,揭示LPMO11基因在P.anserina菌株的生长发育和木质纤维素降解过程中的作用。实验结果表明,在不同纤维素碳源上,ΔBΔCΔE、ΔAΔBΔCΔE、ΔAΔCΔDΔE和ΔAΔBΔCΔDΔE突变型菌株的有性生殖能力降低,其余突变型菌株的孢子萌发效率、生长速率和生殖能力几乎没有差异。PaLPMO11家族5个基因的同时缺失,会导致菌株利用各种碳源的能力明显降低、生长速率降低、孢子萌发率降低、子实体数减少、部分子实体发育异常、寿命缩短和降解纤维素的能力显著下降,但仍有野生型45%以上的总纤维素酶活力。上述结果表明,LPMO11基因可能参与P.anserina的生长发育、有性生殖、衰老和纤维素降解过程。本研究为系统阐述丝状真菌P.anserina中木质纤维素降解的调控机制提供参考。 展开更多
关键词 丝状真菌 Podospora anserina LPMO11 基因敲除 木质纤维素降解
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双杂原子配位提高单原子锰位点的析氧活性
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作者 白雪 韩璟怡 +2 位作者 陈思雨 牛效迪 管景奇 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第11期212-219,共8页
可再生能源的储存和转化可以增加能源利用的可及性,是目前能源发展的主要方向.析氧反应(OER)是电解水与可充电锌-空气电池的重要半反应,然而其较高的反应势垒降低了能源利用效率.因此,开发高效和稳定的OER催化剂是提升能源利用的关键.... 可再生能源的储存和转化可以增加能源利用的可及性,是目前能源发展的主要方向.析氧反应(OER)是电解水与可充电锌-空气电池的重要半反应,然而其较高的反应势垒降低了能源利用效率.因此,开发高效和稳定的OER催化剂是提升能源利用的关键.由于具有低成本和高原子利用率的优势,非贵金属基单原子催化剂已被广泛应用于电催化析氧反应.研究表明,单原子催化剂的OER活性与其电子结构密切相关.改变配位原子的种类和配位数可以调节单金属原子的d电子结构和自旋状态,进一步优化反应中间体的吸附.锰(Mn)是自然界光合作用系统的析氧中心,近年来模拟Mn结构以最大程度激发催化活性受到了广泛的关注.本文采用双杂原子配位方法来调节孤立锰位点的电子结构从而提升其OER性能.以氧化石墨烯、氯化锰和硫粉为前驱体,合成了双杂原子配位的单原子锰催化剂Mn-SG-500(退火温度为500℃),其中单锰原子与两个硫原子和两个氧原子配位.能谱分析(EDS)和X射线衍射(XRD)谱图中均未观察到锰基纳米粒子,高角环形暗场-扫描透射电子显微镜(HAADF-STEM)图像显示均匀分散的亮点,表明锰以单原子形式负载在石墨烯上.Mn的扩展X射线吸收精细结构(EXAFS)光谱结果表明,Mn-SG-500中的Mn表现出接近+2的化合价,且不存在Mn-Mn键,进一步说明Mn以单原子形式存在.拟合结果显示,Mn-S键长为2.34±0.07?,配位数为1.7±0.4;Mn-O键长为1.94±0.05?,配位数为1.8±0.4.电化学测试结果表明,在碱性条件下,Mn-SG-500在电流密度为10 mA cm^(-2)时的过电位为332 mV,Tafel斜率为56 mV dec-1.与无硫掺杂样品Mn-G-500相比,其过电位(η10)降低了59 mV.根据Arrhenius公式计算,S/O和Mn共配位降低了OER活化能.此外,在1.6 V(vs.RHE)电压下,Mn-SG-500连续运行25 h仍可保持电流密度在10 mA cm^(-2)以上.差分脉冲伏安(DPV)结果表明,在OER过程中,锰的价态由+2变为+4,说明四价锰是析氧反应的关键物种.反应后的Mn 2p XPS谱图也证实了Mn(Ⅳ)的生成.此外,硫的加入使Mn4+到MN_(2)+的还原电位从1.39 V降至1.348 V,提高了OER活性.通过理论计算进一步揭示Mn-SG-500上OER催化活性中心为Mn-S2O_(2),速率控步为*O氧化成*OOH,其理论过电位为0.9 V,远小于硫或氧单独配位的Mn-S4和Mn-O4.综上所述,催化剂Mn-SG-500的析氧活性提高是由于S和O的共配位引起了Mn电荷的重新分配和优化,这对其它过渡金属基催化剂的进一步结构设计和性能优化具有参考意义,也为相关催化领域的研究提供借鉴. 展开更多
关键词 双杂原子配体 原位拉曼 析氧反应 单原子催化剂 理论计算
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An intelligent task offloading algorithm(iTOA)for UAV edge computing network 被引量:8
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作者 Jienan chen siyu chen +3 位作者 siyu Luo Qi Wang Bin Cao Xiaoqian Li 《Digital Communications and Networks》 SCIE 2020年第4期433-443,共11页
Unmanned Aerial Vehicle(UAV)has emerged as a promising technology for the support of human activities,such as target tracking,disaster rescue,and surveillance.However,these tasks require a large computation load of im... Unmanned Aerial Vehicle(UAV)has emerged as a promising technology for the support of human activities,such as target tracking,disaster rescue,and surveillance.However,these tasks require a large computation load of image or video processing,which imposes enormous pressure on the UAV computation platform.To solve this issue,in this work,we propose an intelligent Task Offloading Algorithm(iTOA)for UAV edge computing network.Compared with existing methods,iTOA is able to perceive the network’s environment intelligently to decide the offloading action based on deep Monte Calor Tree Search(MCTS),the core algorithm of Alpha Go.MCTS will simulate the offloading decision trajectories to acquire the best decision by maximizing the reward,such as lowest latency or power consumption.To accelerate the search convergence of MCTS,we also proposed a splitting Deep Neural Network(sDNN)to supply the prior probability for MCTS.The sDNN is trained by a self-supervised learning manager.Here,the training data set is obtained from iTOA itself as its own teacher.Compared with game theory and greedy search-based methods,the proposed iTOA improves service latency performance by 33%and 60%,respectively. 展开更多
关键词 Unmanned aerial vehicles(UAVs) Mobile edge computing(MEC) Intelligent task offloading algorithm(iTOA) Monte Carlo tree search(MCTS) Deep reinforcement learning Splitting deep neural network(sDNN)
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Downregulation of ceramide synthase 1 promotes oral cancer through endoplasmic reticulum stress 被引量:4
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作者 Wen chen chenzhou Wu +9 位作者 Yafei chen Yuhao Guo Ling Qiu Zhe Liu Haibin Sun siyu chen Zijian An Zhuoyuan Zhang Yi Li Longjiang Li 《International Journal of Oral Science》 SCIE CAS CSCD 2021年第1期108-116,共9页
C18 ceramide plays an important role in the occurrence and development of oral squamous cell carcinoma.However,the function of ceramide synthase 1,a key enzyme in C18 ceramide synthesis,in oral squamous cell carcinoma... C18 ceramide plays an important role in the occurrence and development of oral squamous cell carcinoma.However,the function of ceramide synthase 1,a key enzyme in C18 ceramide synthesis,in oral squamous cell carcinoma is still unclear.The aim of our study was to investigate the relationship between ceramide synthase 1 and oral cancer.In this study,we found that the expression of ceramide synthase 1 was downregulated in oral cancer tissues and cell lines.In a mouse oral squamous cell carcinoma model induced by 4-nitroquinolin-1-oxide,ceramide synthase 1 knockout was associated with the severity of oral malignant transformation.Immunohistochemical studies showed significant upregulation of PCNA,MMP2,MMP9,and BCL2 expression and downregulation of BAX expression in the pathological hyperplastic area.In addition,ceramide synthase 1 knockdown promoted cell proliferation,migration,and invasion in vitro.Overexpression of CERS1 obtained the opposite effect.Ceramide synthase 1 knockdown caused endoplasmic reticulum stress and induced the VEGFA upregulation.Activating transcription factor 4 is responsible for ceramide synthase 1 knockdown caused VEGFA transcriptional upregulation.In addition,mild endoplasmic reticulum stress caused by ceramide synthase 1 knockdown could induce cisplatin resistance.Taken together,our study suggests that ceramide synthase 1 is downregulated in oral cancer and promotes the aggressiveness of oral squamous cell carcinoma and chemotherapeutic drug resistance. 展开更多
关键词 endoplasmic CANCER reticulum
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Effective Iterated Greedy Algorithm for Flow-Shop Scheduling Problems with Time lags 被引量:3
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作者 Ning ZHAO Song YE +1 位作者 Kaidian LI siyu chen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第3期652-662,共11页
Flow shop scheduling problem with time lags is a practical scheduling problem and attracts many studies. Permutation problem(PFSP with time lags) is concentrated but non-permutation problem(non-PFSP with time lags... Flow shop scheduling problem with time lags is a practical scheduling problem and attracts many studies. Permutation problem(PFSP with time lags) is concentrated but non-permutation problem(non-PFSP with time lags) seems to be neglected. With the aim to minimize the makespan and satisfy time lag constraints, efficient algo- rithms corresponding to PFSP and non-PFSP problems are proposed, which consist of iterated greedy algorithm for permutation(IGTLP) and iterated greedy algorithm for non-permutation (IGTLNP). The proposed algorithms are verified using well-known simple and complex instances of permutation and non-permutation problems with various time lag ranges. The permutation results indicate that the proposed IGTLP can reach near optimal solution within nearly 11% computational time of traditional GA approach. The non-permutation results indicate that the proposed IG can reach nearly same solution within less than 1% com- putational time compared with traditional GA approach. The proposed research combines PFSP and non-PFSP together with minimal and maximal time lag consideration, which provides an interesting viewpoint for industrial implementation. 展开更多
关键词 PERMUTATION Non-permutation Flow shopTime lags . Makespan Iterated greedy algorithm
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Control of Magnetic Particle Size in Ferrofluid and Its Effect on Rheological Properties 被引量:1
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作者 siyu chen Decai Li 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2022年第3期227-235,共9页
Rheological properties are the theoretical basis and the key to common problems in ferrofluid applications,therefore they are expected to be adjustable to satisfy different technical requirements through altering the ... Rheological properties are the theoretical basis and the key to common problems in ferrofluid applications,therefore they are expected to be adjustable to satisfy different technical requirements through altering the microstructure of ferrofluid during the process of preparation.In this paper,Four ferrofluid samples with different magnetic particle size were prepared by controlling the concentration of precursor solution during co-precipitation process and the rheological properties of these samples were investigated.These samples exhibited field-controlled rheological properties.Eternal magnetic field would enhance the formation of microstructures,resulting in an increase of viscosity.While with the increase of shear rate,microstructures tended to be destroyed,causing viscosity to decrease.There were two opposing mechanisms of the influence of precursor solution concentration.On one hand,the reduction of the precursor solution concentration would produce primary magnetic particles of smaller size.But on the other hand,the surfactant became insufficient to completely coat the magnetic particles because of an increased specific surface area,causing the magnetic particles to aggregate and form secondary clustering structures which strongly enhanced the magnetoviscous effect and weakened the viscoelastic effect. 展开更多
关键词 FERROFLUID RHEOLOGY Magnetoviscous effect Viscoelastic effect
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Screening of nanobody against Microcystis from a human phage display nanobody library 被引量:1
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作者 Yao ZU Wenjie MIAO +4 位作者 Yu LUO chen XU Qianhui PAN siyu chen Jianhong LI 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2022年第5期1696-1705,共10页
Microcystis species identification is essential for ecological studies and water bloom control.Immunoassays are more specific and convenient and several approaches have been used to develop for diagnosing harmful red ... Microcystis species identification is essential for ecological studies and water bloom control.Immunoassays are more specific and convenient and several approaches have been used to develop for diagnosing harmful red tide algae.Howeve r,inve stigations onMicrocystis identification using immunological approaches are still in the initial stage.In this study.Microcystis aeruginosa PCC7806 lysates were utilized as coated antigens to enrich and screen specific Microcystis nanobodies from a human domain antibody display library.After three rounds of enrichment,10 positive monoclonal particles were isolated from the library and the most two positive nanobodies(DAb2 and Dab3)were effectively produced in Escherichia coli BL21.Finally,the DAb2 showed specific immune binding to different Microcystis by the immuno-dot blot assay.This antibody could be used to establish an immunological method to identify Microcystis. 展开更多
关键词 control utilized identification
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Finite Control Set Model Predictive Current Control of a Five-Phase PMSM with Virtual Voltage Vectors and Adaptive Control Set 被引量:9
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作者 Wusen Wang Ying Fan +1 位作者 siyu chen Qiushi Zhang 《CES Transactions on Electrical Machines and Systems》 2018年第1期136-141,共6页
This paper presents an improved finite control set model predictive current control(FCS-MPCC)of a five-phase permanent magnet synchronous motor(PMSM).First,to avoid including all the 32 voltage vectors provided by a t... This paper presents an improved finite control set model predictive current control(FCS-MPCC)of a five-phase permanent magnet synchronous motor(PMSM).First,to avoid including all the 32 voltage vectors provided by a two-level five-phase inverter into the control set,virtual voltage vectors are adopted.As the third current harmonics can be much reduced by virtual voltage vectors automatically,the harmonic items in the cost function of conventional FCS-MPCC are not considered.Furthermore,an adaptive control set is proposed based on voltage prediction.Best control set with proper voltage vector amplitude corresponding to different rotor speed can be achieved by this method.Consequently,current ripples can be largely reduced and the system performs much better.At last,simulations are established to verify the steady and transient performance of the proposed FCS-MPCC,and experiments based on a 2 kW five-phase motor are carried out.The results have validated the performance improvement of the proposed control strategy. 展开更多
关键词 Adaptive control set current ripple finite control set model predictive current control(FCS-MPCC) permanent magnet synchronous motor(PMSM) virtual voltage vectors
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A state-of-the-art review of asphalt pavement surface texture and its measurement techniques 被引量:7
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作者 siyu chen Xiyin Liu +5 位作者 Haoyuan Luo Jiangmiao Yu Fuda chen Yang Zhang Tao Ma Xiaoming Huang 《Journal of Road Engineering》 2022年第2期156-180,共25页
To understand the research status of asphalt pavement texture,the related achievements and progress of pavement surface texture were systematically sorted out from three aspects:the characterization of pavement surfac... To understand the research status of asphalt pavement texture,the related achievements and progress of pavement surface texture were systematically sorted out from three aspects:the characterization of pavement surface texture,the texture measurement and evaluation,and the relationship between texture and the skid resistance.Based on the statistical geometric characteristics,the spectral characteristics,the fractal characteristics and the multifractal characteristics,the characteristics of pavement texture were discussed.The test methods of pavement texture were divided into two categories:direct measurement methods and indirect measurement methods.The advantages and disadvantages of each measurement method were summarized.The effects of macro-texture and micro-texture on asphalt pavement were discussed,respectively.The relationship between texture and skid resistance was studied.This review shows that multifractal theory should be further studied from the aspect of road engineering.High-precision non-contact integrated detection technology should be further studied to meet the needs of complex testing environments.The method of finite element numerical simulation has potential for the analysis of pavement skid resistance.In addition,methods such as big data analysis,neural network,and deep learning should be studied to achieve the intelligent perception and management of the whole state of skid resistance prediction. 展开更多
关键词 Asphalt pavement Surface texture MEASUREMENT Skid resistance FRICTION
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Effect of pulse duration on generation of attosecond pulse with coherent wake emission
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作者 siyu chen Zhinan Zeng Ruxin Li 《Chinese Physics B》 SCIE EI CAS CSCD 2021年第11期352-357,共6页
High-order harmonics and attosecond pulse generation with coherent wake emission are theoretically investigated for the effect of pulse duration and carrier envelope phase(CEP)of few-cycle laser pulse.We find that sho... High-order harmonics and attosecond pulse generation with coherent wake emission are theoretically investigated for the effect of pulse duration and carrier envelope phase(CEP)of few-cycle laser pulse.We find that short pulse duration will cause the negative chirp for the high harmonics.When the laser pulse is shortened to a few cycles,the influence of the laser CEP on the chirp of the harmonics will also become more prominent. 展开更多
关键词 coherent wake emission carrier envelope attosecond pulse high-order harmonics
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Understanding Third Pole Atmospheric Dynamics and Land Surface Processes and Their Associations with the Cryosphere,Air Quality,and Climate Change--Preface to the Special Issue on Third Pole Atmospheric Physics,Chemistry,and Hydrology
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作者 Yun Qian Hailong Wang +4 位作者 Chuanfeng Zhao Chun Zhao siyu chen Xiao-Ming Hu Shichang Kang 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第7期1017-1020,共4页
The Tibetan Plateau(TP),widely known as the Third Pole,is the highest and largest plateau on Earth.The TP not only plays an important role in influencing the atmospheric circulation,surface energy budget,ecology,weath... The Tibetan Plateau(TP),widely known as the Third Pole,is the highest and largest plateau on Earth.The TP not only plays an important role in influencing the atmospheric circulation,surface energy budget,ecology,weather,and climate but also acts as the Asian Water Tower by holding the largest ice mass outside the polar regions to supply fresh water to over 1.4 billion people downstream in Asia(Qin et al.,2006).The observed historical warming and projected future warming over the TP are much stronger than the corresponding global average(Wang et al.,2008).Glaciers on the TP have been retreating extensively in recent decades,driven by atmospheric warming and circulation changes associated with increasing concentrations of greenhouse gases and aerosols in the atmosphere,light-absorbing particles(e.g.,black carbon,dust)on snow,and other factors(Duan et al.,2012;Qian et al.,2011;Zhao et al.,2020).In addition,due to the thermal and dynam-ical effects of the TP,as well as its proximity to the stratosphere,unique atmospheric boundary layer structures often develop over the TP and in the surrounding areas,which have important impacts on local weather,climate,and mixing and transport of atmospheric constituents(Zhao et al.,2020).The TP is considered a natural laboratory to study multi-sphere inter-actions.A systematic mechanistic understanding of the atmospheric chemical and microphysical processes,climate change,cryospheric variability,and the subsequent environmental impacts is particularly important in the context of the unpreceden-ted warming over the TP(Yao et al.,2019). 展开更多
关键词 WARMING weather PLATEAU
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Characteristic chemical profile of Juhe Fang extract with lipid-lowering properties
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作者 Jing Kong Lulu Liu +6 位作者 Yuanyuan Gao siyu chen Linfu Li Yisong Shu Daohan Sun Yanyan Jiang Renbing Shi 《Journal of Traditional Chinese Medical Sciences》 2020年第3期233-244,共12页
Objective:The objective of this study was to verify the lipid-lowering effect of Juhe Fang extract(JHFE)and to determine its characteristic chemical profile in vitro and in vivo.Methods:A hyperlipidemia model was esta... Objective:The objective of this study was to verify the lipid-lowering effect of Juhe Fang extract(JHFE)and to determine its characteristic chemical profile in vitro and in vivo.Methods:A hyperlipidemia model was established by feeding mice a high-fat diet(HFD).After treatment for 30 days,serum total cholesterol(TC),triglyceride(TG),high-density lipoprotein cholesterol(HDL-C)and low-density lipoprotein cholesterol(LDL-C)levels were measured with an automatic biochemistry analyzer.The components from JHFE obtained from in vivo and in vitro experiments were investigated using an UPLC-Q Exactive-Orbitrap MS/MS.Results:The TC,TG,and LDL-C in the serum significantly decreased and the HDL-C significantly increased after JHFE treatment.A total of 95 compounds from JHEF including 15 phenolic acids(PA),4 phenylethanoid glycosides(PG),24 flavonoids(F),14 triterpenoids(T),10 diterpenoid glycosides(D),18 alkaloids(A)and 10 others(O)were identified.Trigonelline was discovered for the first time in a herbal medicine of Juhe Fang.Furthermore,68 compounds were identified in vivo including 28 prototype compounds and 40 metabolites.The metabolic characteristics of these components were revealed including identification of new metabolites of 4-hydroxyphenyl ethyl-8-O-[a-L-arabinopyranosyl-(1/6)]-b-D-glucopyranoside(PEG)and lirinidine.A total of 43 components from JHFE were absorbed and/or metabolized.The contribution rate of each type of chemical component from JHFE to its lipidlowering effect from high to low were A,F,PG,PA,D and T.Conclusion:The results of this study showed that JHFE demonstrated a significant lipid-lowering effect in a high-fat diet(HFD)-induced hyperlipidemia mouse model.Specific types of PA,PG,F,D,T and A formed the pharmaceutical architecture of the lipid-lowering effect of JHFE.This study should prove useful for clarifying the components responsible for the lipid-lowering effect of JHFE and provide a basis for precision quality control research. 展开更多
关键词 Juhe fang Lipid-lowering effect UPLC-Q exactive-orbitrap MS/MS Chemical characteristic profile Pharmaceutical architecture
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A Two-Stage Highly Robust Text Steganalysis Model
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作者 Enlu Li Zhangjie Fu +1 位作者 siyu chen Junfu chen 《Journal of Cyber Security》 2020年第4期183-190,共8页
With the development of natural language processing,deep learning,and other technologies,text steganography is rapidly developing.However,adversarial attack methods have emerged that gives text steganography the abili... With the development of natural language processing,deep learning,and other technologies,text steganography is rapidly developing.However,adversarial attack methods have emerged that gives text steganography the ability to actively spoof steganalysis.If terrorists use the text steganography method to spread terrorist messages,it will greatly disturb social stability.Steganalysis methods,especially those for resisting adversarial attacks,need to be further improved.In this paper,we propose a two-stage highly robust model for text steganalysis.The proposed method analyzes and extracts anomalous features at both intra-sentential and inter-sentential levels.In the first phase,every sentence is first transformed into word vectors.To obtain a high dimensional sentence vector,we use Bi-LSTM to obtain feature information for all words in the sentence while retaining strong correlations.In the second phase,we input multiple sentences vectors into the GNN,from which we extract inter-sentential anomaly features and make a judgment as to whether the text contains secret messages.In addition,to improve the robustness of the model,we add adversarial examples to the training set to improve the robustness and generalization of the steganalysis model.Theoretically,our proposed method is more robust and more accurate in detection compared to existing methods. 展开更多
关键词 Text steganalysis adversarial attack natural language processing deep learning
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聚合物-脂质纳米粒用于增强酪氨酸血症I型治疗性碱基编辑器质粒的肝靶向递送研究
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作者 高达同 林萌 +11 位作者 彭祎玮 李嘉嘉 杨宜靓 滕雨璐 陈思宇 孙雯 吴子楠 袁泉 仰浈臻 周艳霞 李馨儒 齐宪荣 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2024年第3期189-200,共12页
酪氨酸血症I型是一种罕见的常染色体隐性遗传病,目前尚无有效的治疗方法。近年来,以碱基编辑器为代表的基因编辑技术已被报道用于酪氨酸血症I型的治疗。然而,由于生理屏障的存在,碱基编辑器递送困难。在本研究中,我们构建了一种靶向去... 酪氨酸血症I型是一种罕见的常染色体隐性遗传病,目前尚无有效的治疗方法。近年来,以碱基编辑器为代表的基因编辑技术已被报道用于酪氨酸血症I型的治疗。然而,由于生理屏障的存在,碱基编辑器递送困难。在本研究中,我们构建了一种靶向去唾液酸糖蛋白受体的聚合物-脂质纳米递送系统,用于改善酪氨酸血症I型治疗性核酸药物的递送效率。我们首先合成了一种生物可降解性丙烯酸酯-氨基醇共聚物用于递送碱基编辑器质粒,其转染效率显著优于市售转染试剂Hieff Trans^(TM)。随后,共聚物纳米粒与DOPE-PEG-Gal NAc自组装形成聚合物-脂质纳米粒,用于增强纳米粒的肝脏递送效率。在体外转染实验中,包载Fah-p CMV-ABE6.3-EGFP碱基编辑器质粒的聚合物-脂质纳米粒表现出了良好的肝细胞选择性,其转染效率是游离质粒的70倍以上。研究表明,携带肝靶向配体的聚合物-脂质纳米递送系统能够有效增强治疗性碱基编辑器质粒的肝靶向递送效率并为酪氨酸血症I型的基因治疗提供了一种潜在的递送载体。 展开更多
关键词 酪氨酸血症I型 碱基编辑器 聚合物-脂质纳米粒 转染效率 基因递送
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Investigation of surface textures deterioration on pavement skid-resistance using hysteresis friction models and numerical simulation method 被引量:2
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作者 Haoyuan LUO siyu chen +4 位作者 Leyi ZHU Xiyin LIU Yangzezhi ZHENG Runming ZHAO Xiaoming HUANG 《Friction》 SCIE EI CAS CSCD 2024年第4期745-779,共35页
Many rubber friction theories or some method combined theories and field-experiments are employed to evaluate the pavement skid-resistance deterioration due to the evolution of surface textures.However,these methods a... Many rubber friction theories or some method combined theories and field-experiments are employed to evaluate the pavement skid-resistance deterioration due to the evolution of surface textures.However,these methods are difficult to be implemented in the analysis of situations with multi-factor coupling and some extreme conditions.This study developed a framework to evaluate the skid-resistance deterioration of asphalt pavements.In this framework,the portable laser scanning was used to create the digital worn pavement model,and a hydroplaning finite element(FE)model for these digital worn pavements was constructed to evaluate coupling effects of the texture evolution and factors of slip ratio,slip angle,velocity and water film on braking-cornering characteristics of tire.In this study,the deterioration of skid-resistance of five typical asphalt pavements due the surface texture wear was systematically investigated by this framework.Compared with previous works,this study established the rubber friction models for each digital worn pavement considering the energy hysteresis of rubber and the power spectrum density of surface texture.And the rubber friction model was used to define the interaction behaviors between the tire and corresponding wore pavements in the FE hydroplaning model,rather than using an empirical friction model or a fixed friction coefficient. 展开更多
关键词 worn pavement skid-resistance friction coefficient textures evolution water film computer numerical simulation
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Surface reconstruction and structural transformation of twodimensional Ni-Fe MOFs for oxygen evolution in seawater media 被引量:2
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作者 Liyuan Xiao Xue Bai +7 位作者 Jingyi Han Tianmi Tang siyu chen Hui Qi Changmin Hou Fuquan Bai Zhenlu Wang Jingqi Guan 《Nano Research》 SCIE EI CSCD 2024年第4期2429-2437,共9页
As a four-electron transfer reaction,oxygen evolution reaction(OER)is limited by large overpotential and slow kinetics.Here,we in-situ synthesized two-dimensional(2D)Ni-Fe metal-organic framework nanosheets on nickel ... As a four-electron transfer reaction,oxygen evolution reaction(OER)is limited by large overpotential and slow kinetics.Here,we in-situ synthesized two-dimensional(2D)Ni-Fe metal-organic framework nanosheets on nickel foam(NixFe-TPA/NF,TPA=terephthalic acid)for oxygen evolution in alkaline and alkaline seawater electrolytes.In 1 M KOH,Ni3Fe-TPA/NF shows a low overpotential(η10)of 189 mV at 10 mA·cm^(-2) and an ultra-low overpotential of only 260 mV at 500 mA·cm^(-2).In alkaline seawater,Ni3Fe-TPA/NF still provides impressive OER performance,with anη10 of 265 mV.In-situ Raman characterization results show that the phase transition occurs during the OER,and Ni3FeOOH with more oxygen vacancies is in-situ formed,reducing the OER energy barrier.Density functional theory(DFT)reveals that the synergy between Ni and Fe reduces the energy barrier and accelerates the rate-determining step.In addition,the ultra-thin 2D sheet structure and the close combination of Ni3FeOOH and highly conductive NF support ensure the high catalytic OER activity.Therefore,the surface reconstruction and structural modification strategy can be used to design and prepare high-performance OER electrocatalysts for energy-related applications. 展开更多
关键词 density functional theory(DFT)calculation Ni3FeOOH oxygen evolution reaction seawater electrolysis surface reconstruction
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Development of the second version of Global Prediction System for Epidemiological Pandemic 被引量:1
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作者 Jianping Huang Li Zhang +9 位作者 Bin chen Xiaoyue Liu Wei Yan Yingjie Zhao siyu chen Xinbo Lian Chuwei Liu Rui Wang Shuoyuan Gao Danfeng Wang 《Fundamental Research》 CAS CSCD 2024年第3期516-526,共11页
Coronavirus disease 2019(COvID-19)is a severe global public health emergency that has caused a major cri-sis in the safety of human life,health,global economy,and social order.Moreover,CovID-19 poses significant chall... Coronavirus disease 2019(COvID-19)is a severe global public health emergency that has caused a major cri-sis in the safety of human life,health,global economy,and social order.Moreover,CovID-19 poses significant challenges to healthcare systems worldwide.The prediction and early warning of infectious diseases on a global scale are the premise and basis for countries to jointly fight epidemics.However,because of the complexity of epidemics,predicting infectious diseases on a global scale faces significant challenges.In this study,we developed the second version of Global Prediction System for Epidemiological Pandemic(GPEP-2),which combines statis-tical methods with a modified epidemiological model.The GPEP-2 introduces various parameterization schemes for both impacts of natural factors(seasonal variations in weather and environmental impacts)and human so-cial behaviors(government control and isolation,personnel gathered,indoor propagation,virus mutation,and vaccination).The GPEP-2 successfully predicted the COVID-19 pandemic in over 180 countries with an average accuracy rate of 82.7%.It also provided prediction and decision-making bases for several regional-scale CovID-19 pandemic outbreaks in China,with an average accuracy rate of 89.3%.Results showed that both anthropogenic and natural factors can affect virus spread and control measures in the early stages of an epidemic can effectively control the spread.The predicted results could serve as a reference for public health planning and policymaking. 展开更多
关键词 COVID-19 Epidemiological model Prediction GPEP SEIR Statistical-dynamic
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