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Aggregate 2024年第1期5卷 331-336页

作者： wu-jie guo Shixiang Ma Hui Wang Lu Qiao Lei Chen Chenyu Hong Bin Liu Xiaoyan Zheng Hui-Qing Peng State Key Laboratory of Chemical Resource Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijingChina Key Laboratory of Cluster Science of Ministry of Education Beijing Key Laboratory of Photoelectronic/Electro-photonic Conversion MaterialsKey Laboratory of Medicinal Molecule Science and Pharmaceutics Engineering of Ministry of Industry and Information TechnologySchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijingChina

Quantitatively establishing the correlation between nanoparticle size and fluorescence is essential for understanding the behavior and functionality of fluorescent nanoparticles(FNPs).However,such exploration focusing on organic FNPs has not been achieved to ***,we employ the use of supramolecular polymeric FNPs prepared from tetraphenylethylene-based bis-ureidopyrimidinone monomers(bis-UPys)to relate the size to the fluorescence of organic *** an equal concentration of bis-UPys,a logarithmic relationship between them is built with a correlation coefficient higher than *** calculations indicate that variations in fluorescence intensity among FNPs of different sizes are attributed to the distinct molecular packing environments at the surface and within the interior of the *** leads to different nonradiative decay rates of the embedded and exposed bis-UPys and thereby changes the overall fluorescence quantum yield of nanoparticles due to their different specific surface *** established fluorescence intensity-size correlation possesses fine universality and reliability,and it is successfully utilized to estimate the sizes of other nanoparticles,including those in highly diluted dispersions of *** work paves a new way for the simple and real-time determination of nanoparticle sizes and offers an attractive paradigm to optimize nanoparticle functionalities by the size effect.

关键词： aggregation-induced emission fluorescence detection fluorescent nanoparticle nanoparticle size supramolecular polymer

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感染性休克患者SAA及ChE和Ppv-aCO_(2)与预后的关联及预测价值

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中华医院感染学杂志 2024年第9期34卷 1281-1285页

作者：吴国杰赵静贾浩然王晓玲烟台市烟台山医院东院重症医学科山东烟台264003 烟台市疾病预防控制中心办公室山东烟台264003

目的探讨感染性休克患者外周血淀粉样蛋白A(SAA)、胆碱酯酶(ChE)及外周静脉-动脉二氧化碳分压差(Ppv-aCO_(2))对预后不良的预测价值。方法收集2021年2月-2023年2月在烟台市烟台山医院接受治疗的212例感染性休克患者的临床资料,将入院后2... 详细信息

目的探讨感染性休克患者外周血淀粉样蛋白A(SAA)、胆碱酯酶(ChE)及外周静脉-动脉二氧化碳分压差(Ppv-aCO_(2))对预后不良的预测价值。方法收集2021年2月-2023年2月在烟台市烟台山医院接受治疗的212例感染性休克患者的临床资料,将入院后28 d生存的149例患者纳入预后良好组,入院后28 d死亡的63例患者纳入预后不良组,比较两组患者临床资料,分析外周血SAA、ChE、Ppv-aCO_(2)水平对感染性休克患者预后不良的预测价值。结果预后不良组患者年龄大于预后良好组(P<0.05);序贯器官衰竭评分(SOFA)、急性生理与慢性健康评分(APACHEⅡ)均高于预后良好组(P<0.05);两组患者SAA水平及Ppv-aCO_(2)均高于预后良好组(P<0.05),ChE水平低于预后良好组(P<0.05);受试者工作特征(ROC)曲线分析,结果显示SAA、ChE、Ppv-aCO_(2)联合预测感染性休克预后不良的曲线下面积(AUC)为0.859、敏感度和特异度分别为76.19%和83.89%。结论感染性休克患者SAA、ChE及Ppv-aCO_(2)可用于感染性休克患者预后不良的评估,三者联合检测的预测价值更高。

关键词：感染性休克淀粉样蛋白A 胆碱酯酶外周血静脉-动脉二氧化碳分压差预测价值预后

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Ratiometric hypoxia detection by bright organic room temperature phosphorescence of uniformed silica nanoparticles in water

聚集体(英文)

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聚集体(英文) 2023年第1期4卷 158-164页

作者： Tong He wu-jie guo Yu-Zhe Chen Xiao-Feng Yang Chen-Ho Tung Li-Zhu wu Key Laboratory of Photochemical Conversion and Optoelectronic Materials&CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijingChina Department of Chemistry North University of ChinaTaiyuanChina University of Chinese Academy of Sciences BeijingChina

Organic room temperature phosphorescence(RTP)in water has attracted much attention recently for its potential biological ***,it remains a formidable challenge to achieve efficient RTP from pure organic compounds in aqueous phase due to the dramatic deactivation of triplet excited states in water and the poor water dispersibility of large organic particles/*** herein is covalent incorporation of a pure organic monochromophore in silica nanoparticles(SiNPs)featuring fluorescence and bright phosphorescence in aqueous *** covalent bonding of organic phosphors in polysiloxane framework was found to show excellent water dispersibility,at the same time suppress the nonradiative deactivation of triplet excited states especially from water,thus leading to high phosphorescence quantum yields(up to 22%)and long lifetimes(up to 3.5 ms)in aqueous *** strikingly,oxygen-insensitive fluorescence as internal reference and oxygen-dependent phosphorescence as oxygen indicator from the organic chromophore in the porous SiNPs realized ratiometric hypoxia detection with ultrasensitivity(K_(SV)=449.3 bar^(-1)).

关键词： aqueous solution hypoxia detection pure organic compound room temperature phosphorescence silica nanoparticle

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A model reduction approach for discrete-time linear time-variant systems with delayed inputs

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Science China(Information Sciences) 2024年第4期67卷 197-217页

作者： Ai-guo wu Guang-Ren DUAN Yu WANG jie ZHANG School of Mechanical Engineering and Automation Harbin Institute of Technology(Shenzhen) HIT wuhu Robot Technology Research Institute Center for Control Science and Technology Southern University of Science and Technology

A model reduction approach is presented for discrete-time linear time-variant input-delayed systems. According to this proposed approach, a dynamical variable is constructed by taking advantage of the current state and historical information of input. It is revealed that the behavior of this dynamical variable is governed by a discrete-time linear delay-free system. It is worth noting that the presented variable transformation does not require the system matrix to be invertible. Based on the reduced delay-free models,stabilizing control laws can be easily obtained for the original delayed system. For the case with a single input delay, the constructed variable is an exact prediction for the future state, and thus the stabilizing control law could be designed by replacing the future state with its prediction. Finally, three discrete-time periodic systems with delayed input are employed to illustrate how to utilize the presented model reduction approaches.

关键词： reduction approach predictor-based feedback time-varying systems delayed input periodic system

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Ultralong Room-Temperature Phosphorescence of Silicon-Based Pure Organic Crystal for Oxygen Sensing

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CCS Chemistry 2022年第3期4卷 1007-1015页

作者： wu-jie guo Yu-Zhe Chen Chen-Ho Tung Li-Zhu wu Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190 University of Chinese Academy of Sciences Beijing 100049

Quantitative oxygen detection is of great importance in biological fields,complex environments,and chemical process *** to the high sensitivity and rapid response of long-lived phosphorescence to oxygen,pure organic room-temperature phosphorescence(RTP)for oxygen detection has recently attracted considerable ***,to simultaneously achieve ultralong phosphorescence at room temperature and quantitative oxygen detection from pure organic crystals is *** packing to restrict nonradiative decay is not apt to allow oxygen diffusion for *** herein is an exceptional example,that is,a crystal of simple carbazole molecules that bridges with an ethoxysilane(DCzC2OSi)and is capable of oxygen sensing with remarkable *** studies and single-crystal structure analysis reveal that DCzC2OSi crystals display ultralong RTP and suitable oxygen diffusion channels from its butterfly-like tetrahedron *** comparisons with the crystals of CzC2OH and DCzSi verify the important roles of silicon and ethoxy groups of DCzC2OSi for both enhanced phosphorescence lifetime and oxygen *** the crystals of DCzC2OSi were doped into polymer,the lifetime-based oxygen sensor exhibited high KSV(5.308 kPa^(−1))with full reversibility,which is attractive for the development of practical oxygen sensors from pure organic crystals.

关键词： pure organic crystal ultralong roomtemperature phosphorescence oxygen sensor molecular packing

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Physicochemical principles of hydrogen metallurgy in blast furnace

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Journal of Iron and Steel Research International 2024年第1期31卷 46-63页

作者： Han-jie guo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials Beijing100083China

Based on the stoichiometric method and the free energy minimization method,an ideal model for the reduction of iron oxides by carbon and hydrogen under blast furnace conditions was established,and the reduction efficiency and theoretical energy consumption of the all-carbon blast furnace and the hydrogen-rich blast furnace were *** results show that after the reduction reaction is completed at the bottom of the blast furnace,the gas produced by reduction at 1600℃still has a certain excessive reduction capacity,which is due to the hydrogen brought in by the hydrogen-rich blast as well as the excess carbon monoxide generated by the reaction of the coke and the oxygen brought in by the *** the process of the gas with excessive reduction capacity rising from the bottom of the blast furnace and gas reduction process,the excessive reduction capacity of the gas gradually decreases with the increase in the dydrogen content in the *** the all-carbon blast furnace,the excess gas reduction capacity is the strongest,and the total energy consumption per ton of iron reduction is the *** shows that,for the current operation mode of the blast furnace,adding hydrogen in the blast furnace cannot reduce the consumption of carbon required for reduction per ton of iron,but rather increases the consumption of carbon.

关键词： Hydrogen metallurgy Excess gas reduction capacity Theoretical energy consumption Hydrogen-rich blast furnace Thermodynamic model Gibbs minimum free energy method

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On the Intelligent Optimization of the Crevice Structure in a Rapid Compression Machine

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Journal of Thermal Science 2024年第3期33卷 1200-1215页

作者： guo Qiang LIU jie wu Yingtao WANG Hewu TANG Chenglong YU Ruiguang Department of Power Mechanical Engineering Beijing Jiaotong UniversityBeijing100044China State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an710049China State Key Laboratory of Automotive Safety and Energy Tsinghua UniversityBeijing100084China Beijing Key Laboratory of New Energy Vehicle Powertrain Technology Beijing100044China National International Science and Technology Cooperation Base Beijing Jiaotong UniversityBeijing100044China

In this study,the multi-objective intelligent optimization of the crevice structure in a rapid compression machine(RCM)is carried out based on the RCM simulation model modified with the KIVA-3V program.A multi-objective optimization simulation model of the crevice structure based on the large eddy simulation model coupled with the genetic algorithm NSGA-Ⅲis *** optimization parameters and seven optimization objectives are selected in the optimization *** results show that the genetic algorithm can quickly find the values of the optimized *** crevice volume ratio shows a trade-off relationship with the dimensionless temperature ratio T_(max)/T_(aver)and the tumble ratio.A larger crevice volume can reduce the flow of boundary layer cryogenic gas into the combustion chamber,thus improving the temperature *** addition,the crevice entrance width and the connecting channel length should be smaller,while the volume of the crevice main chamber should be larger,so as to sufficiently introduce the low-temperature gas of the boundary layer into the crevice and reduce their influence on the temperature field of the combustion *** the crevice volume accounts for10%of the total volume,the temperature uniformity of the combustor is significantly enhanced,and when the crevice volume accounts for 30.4%,there is almost no low-temperature vortex in the combustion chamber.

关键词： rapid compression machine adiabatic core area ignition delay period crevice structure

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Automatic recognition of landslides based on YOLOv7 and attention mechanism

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Journal of Mountain Science 2024年第8期21卷 2681-2695页

作者： SONG Yewei guo jie wu Gaofeng MA Fengshan LI Fangrui Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Sciences Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

Landslide disasters comprise the majority of geological incidents on slopes,posing severe threats to the safety of human lives and property while exerting a significant impact on the geological *** rapid identification of landslides is important for disaster prevention and control;however,currently,landslide identification relies mainly on the manual interpretation of remote sensing *** interpretation and feature recognition methods are time-consuming,labor-intensive,and challenging when confronted with complex ***,automatic landslide recognition has emerged as a pivotal avenue for future *** this study,a dataset comprising 2000 landslide images was constructed using open-source remote sensing images and *** YOLOv7 model was enhanced using data augmentation algorithms and attention *** optimization models were formulated to realize automatic landslide *** findings demonstrate the commendable performance of the optimized model in automatic landslide recognition,achieving a peak accuracy of 95.92%.Subsequently,the optimized model was applied to regional landslide identification,co-seismic landslide identification,and landslide recognition at various scales,all of which showed robust recognition ***,the model exhibits limitations in detecting small targets,indicating areas for refining the deep-learning *** results of this research offer valuable technical support for the swift identification,prevention,and mitigation of landslide disasters.

关键词： Deep learning Landslide detection Natural disasters Attention mechanism Remote sensing

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Emerging direct current triboelectric nanogenerator for high-entropy mechanical energy harvesting

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Science China(Technological Sciences) 2024年第5期67卷 1297-1316页

作者： CHEN jie guo RuiLong guo HengYu College of Physics and Electronic Engineering Chongqing Normal UniversityChongqing 401331China Department of Applied Physics Chongqing UniversityChongqing 401331China

In the era of the Internet of Things(IoT),the provision of sustainable power to distributed,mobile,and low-power-consumption electronic devices is a critical *** overcome this challenge,the triboelectric nanogenerator(TENG),a highly efficient high-entropy mechanical energy harvesting device,was developed in *** device enables the direct conversion of irregular and low-frequency mechanical energy into pulsed alternating current(AC)***,the incompatibility of most electronic devices with AC signals necessitates rectifier circuits or generators that deliver direct current(DC)*** recent years,DC-TENGs have undergone extensive development,achieving significant milestones in various application fields while also facing crucial challenges that require *** this review,three categories of DC-TENG devices with distinct operating mechanisms are comprehensively explored:multiphase coupling,mechanical rectification,and air *** typical structures and working mechanisms are thoroughly discussed,and specific output performance limitations,along with corresponding optimization strategies,are ***,the applications of DC-TENGs in various scenarios are ***,the challenges faced by DC-TENGs and potential solutions are analyzed to guide further advancements in this technology.

关键词： TENG direct current working mechanisms output performance limitations optimization strategies

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A unified stochastic damage model for concrete based on multi-scale energy dissipation analysis

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Science China(Technological Sciences) 2024年第3期67卷 863-877页

作者： guo ChengGong LI jie College of Civil Engineering Tongji UniversityShanghai 200092China State Key Laboratory of Disaster Reduction in Civil Engineering Shanghai 200092China

This work proposes a unified damage model for concrete within the framework of stochastic damage mechanics. Based on the micro-meso stochastic fracture model(MMSF), the nonlinear energy dissipation process of the microspring from nanoscale to microscale is investigated. In nanoscale, the rate process theory is adopted to describe the crack growth rate;therefore, the corresponding energy dissipation caused by a representative crack propagation can be obtained. The scale gap from nanoscale to microscale is bridged by a crack hierarchy model. Thus, the total energy dissipated by all cracks from the nanoscale to the microscale is gained. It is found that the fracture strain of the microspring can be derived from the above multi-scale energy dissipation analysis. When energy dissipation is regarded as some microdamage to the microspring, the constitutive law of the microspring is no longer linearly elastic, as previously assumed. By changing the expression of the damage evolution law from fracture strain to energy dissipation threshold, the new damage evolution model is derived. The proposed model can not only replicate the original static model but also extend to cases of rate dependence. By deriving the fracture strain under different strain rates, the rate sensitivity of concrete materials can be reflected. The model parameters can be conveniently obtained by identifying them with experimental data. Finally, several numerical examples are presented to verify the proposed model.

关键词： concrete damage model stochastic damage rate dependent energy dissipation

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