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Design of p-n homojunctions in metal-free carbon nitride photocatalyst for overall water splitting

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Chinese Journal of Catalysis 2021年第3期42卷 501-509页

作者： Gang Zhao Shuhua Hao Jinghua Guo yupeng xing Lei Zhang Xijin Xu Laboratory of Functional Micro-nano Material and Device School of Physics and TechnologyUniversity of JinanJinan 250022ShandongChina State Key Lab of Crystal Materials Shandong UniversityJinan 250100ShandongChina

Two-dimensional(2D)carbon nitride(CN)photocatalysts are attracting extensive attention owing to their excellent photocatalytic *** this study,we successfully prepared CN materials with heterogeneous structures via hydrothermal treatment,high-temperature roasting,ball milling,sintering,and other *** from interface interactions in hybrid architectures,the CN photocatalysts exhibited high photocatalytic *** rate of hydrogen production using these CN photocatalysts reached 17028.82μmol h^(−1)g^(−1),and the apparent quantum efficiency was 11.2%at 420 *** ns-level time-resolved photoluminescence(PL)spectra provided information about the time-averaged lifetime of fluorescence charge carriers;the lifetime of the charge carriers causing the fluorescence of CN reached 9.99 ***,the CN photocatalysts displayed satisfactory results in overall water splitting without the addition of sacrificial *** average hydrogen and oxygen production rates were 270.95μmol h^(−1)g^(−1)and 115.21μmol h^(−1)g^(−1)in 7 h,respectively,which were promising results for the applications of the catalysts in overall water splitting *** investigated the high efficiency of the prepared CN photocatalysts via a series of tests(UV-vis diffuse reflectance spectroscopy,photocurrent response measurements,PL emission spectroscopy,time-resolved PL spectroscopy,and Brunauer-Emmett-Teller analysis).Furthermore,the Mott-Schottky plot and current-voltage curve were acquired via electrochemical *** fabricated CN photocatalyst had a small p-n junction in its heterogeneous structure,which further enhanced its photocatalytic ***,this work can promote the development of CN photocatalysts.

关键词： 2D Metal-free photocatalyst Carbon nitride Overall water splitting Time-resolved photoluminescence spectra Density-functional theory Heterogeneous structure

Needs and challenges of optical atmospheric monitoring on the background of carbon neutrality in China

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Frontiers of Environmental Science & Engineering 2024年第6期18卷 49-62页

作者： Wenqing Liu Chengzhi xing Anhui Institute of Optics and Fine Mechanics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 23001China

The achievement of the targets of coordinated control of PM2.5 and O3 and the carbon peaking and carbon neutrality depend on the development of pollution and greenhouse gas monitoring *** monitoring technology,based on its technical characteristics of high scalability,high sensitivity and wide-targets detection,has obvious advantages in pollution/greenhouse gases monitoring and has become an important direction in the development of environmental monitoring *** present,a system of environmental optical monitoring technology with differential optical absorption spectroscopy(DOAS),cavity ring-down spectroscopy(CRDS),light detection and ranging(LIDAR),laser heterodyne spectroscopy(LHS),tunable diode laser absorption spectroscopy(TDLAS),fourier transform infrared spectroscopy(FTIR)and fluorescence assay by gas expansion(FAGE)as the main body has been ***,with the promotion of“reduction of pollution and carbon emissions”strategy,there have been significant changes in the sources of pollution/greenhouse gases,emission components and emission concentrations,which have put forward new and higher requirements for the development of monitoring *** the future,we should pay more attention to the development of new optical monitoring techniques and the construction of stereoscopic monitoring system,the interdisciplinarity(among mathematics,physics,chemistry and biology,etc.),and the monitoring of greenhouse gases and research on atmospheric chemistry.

关键词： Pollution Greenhouse gas Optical atmospheric monitoring Needs and challenges

Distributed Fault-Tolerant Control of Uncertain Multi-Agent Systems with Connectivity Maintenance

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Journal of Systems Science & Complexity 2024年第1期37卷 40-62页

作者： xing Xueyan HU Guoqiang Continental-NTU Corporate Lab Nanyang Technological UniversitySingapore 639798Singapore Continental-NTU Corporate Lab and the School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore 639798Singapore

In this paper,a distributed cooperative control protocol is presented to deal with actuator failures of multi-agent systems in the presence of connectivity *** the developed strategy,each agent can track the reference trajectory of the leader in the presence of actuator failures,disturbances and *** connectivity of the multi-agent system can always be ensured during the control *** achieve the aforementioned control objectives,a potential function is introduced to the distributed adaptive fault-tolerant control algorithm to preserve the initial connected network among the *** uncertainty of the multi-agent system,which is allowed to be described by discontinuous functions,is approximated and compensated using the fuzzy logic *** asymptotic stability of the closed-loop system is demonstrated through the use of Cellina’s approximate selection theorem of nonsmooth *** to the developed adaptive laws,the upper bound of the disturbance is allowed to be uncertain,which facilitates the implementation of the control ***,simulation results are provided to verify the effectiveness of the proposed control scheme.

关键词： Actuator failure connectivity maintenance coordination control uncertainties

Reinforcement Learning-Based Dynamic Order Recommendation for On-Demand Food Delivery

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Tsinghua Science and Technology 2024年第2期29卷 356-367页

作者： xing Wang Ling Wang Chenxin Dong Hao Ren Ke xing Department of Automation Tsinghua UniversityBeijing 100080China School of Mechanical and Automotive Engineering Qingdao Hengxing University of Science and TechnologyQingdao 266100China Meituan Beijing 100015China

On-demand food delivery(OFD)is gaining more and more popularity in modern *** a kernel order assignment manner in OFD scenario,order recommendation directly influences the delivery efficiency of the platform and the delivery experience of *** paper addresses the dynamism of the order recommendation problem and proposes a reinforcement learning solution *** actor-critic network based on long short term memory(LSTM)unit is designed to deal with the order-grabbing conflict between different ***,three rider sequencing rules are accordingly proposed to match different time steps of the LSTM unit with different *** test the performance of the proposed method,extensive experiments are conducted based on real data from Meituan delivery *** results demonstrate that the proposed reinforcement learning based order recommendation method can significantly increase the number of grabbed orders and reduce the number of order-grabbing conflicts,resulting in better delivery efficiency and experience for the platform and riders.

关键词： on-demand food delivery order recommendation reinforcement learning actor-critic network long short term memory

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基于优选特征子集的厚板板形质量预测分析

计算机集成制造系统 2022年第7期28卷 2041-2049页

作者：邢玉鹏张同康陆军丁进良东北大学流程工业综合自动化国家重点实验室辽宁沈阳110819

厚板板形质量对于钢铁企业十分重要,由于厚板在生产过程中经过多个工序加工,涉及众多变量,加工后的厚板板形存在质量波动和异常原因未知的问题。针对这一难题,本文利用厚板生产过程中的工业大数据,提出一种具有根因分析能力的厚板板形... 详细信息

厚板板形质量对于钢铁企业十分重要,由于厚板在生产过程中经过多个工序加工,涉及众多变量,加工后的厚板板形存在质量波动和异常原因未知的问题。针对这一难题,本文利用厚板生产过程中的工业大数据,提出一种具有根因分析能力的厚板板形质量预测模型。首先针对厚板板形质量预测问题,由于厚板小批量生产、生产过程变量非线性强,本文采用基于核偏最小二乘(KPLS)的方法建立厚板板形质量预测模型。然后针对厚板板形质量异常原因未知的问题,利用混合整数遗传算法(MIGA)分析影响厚板板形的生产过程工序和变量。通过将MIGA集成到KPLS建模中,选择厚板板形质量预测效果最好时的生产过程工序及变量,用于最终厚板板形质量预测和根因分析。最后,采用来自某钢铁厂的实际工业过程数据进行实验验证,通过工业实验表明,所提算法(KPLS-MIGA)能够实现对厚板板形质量的准确预测,并能够对厚板板形质量异常进行根因分析,从而寻找到影响厚板板形质量的关键变量,对实际的生产操作具有较好的指导意义。

关键词：厚板板形核偏最小二乘质量预测优选特征子集根因分析

Dynamic plugging regulating strategy of pipeline robot based on reinforcement learning

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Petroleum Science 2024年第1期21卷 597-608页

作者： xing-Yuan Miao Hong Zhao College of Mechanical and Transportation Engineering China University of PetroleumBeijing102249China

Pipeline isolation plugging robot (PIPR) is an important tool in pipeline maintenance operation. During the plugging process, the violent vibration will occur by the flow field, which can cause serious damage to the pipeline and PIPR. In this paper, we propose a dynamic regulating strategy to reduce the plugging-induced vibration by regulating the spoiler angle and plugging velocity. Firstly, the dynamic plugging simulation and experiment are performed to study the flow field changes during dynamic plugging. And the pressure difference is proposed to evaluate the degree of flow field vibration. Secondly, the mathematical models of pressure difference with plugging states and spoiler angles are established based on the extreme learning machine (ELM) optimized by improved sparrow search algorithm (ISSA). Finally, a modified Q-learning algorithm based on simulated annealing is applied to determine the optimal strategy for the spoiler angle and plugging velocity in real time. The results show that the proposed method can reduce the plugging-induced vibration by 19.9% and 32.7% on average, compared with single-regulating methods. This study can effectively ensure the stability of the plugging process.

关键词： Pipeline isolation plugging robot Plugging-induced vibration Dynamic regulating strategy Extreme learning machine Improved sparrow search algorithm Modified Q-learning algorithm

Research on the influences of motion characteristics of jetting projectile charge under water

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Defence Technology（防务技术） 2024年第3期33卷 411-425页

作者： xing Chen Yong-gang Lu Institute of Systems Engineering China Academy of Engineering PhysicsMianyang 621900SichuanChina

Shaped charge warhead is important for enhancing the damage performance of underwater *** paper used finite element analysis software and based on JPC water penetration experiments to examine the influence of liner parameters(wall thickness,material),charge aspect ratio,and stand-off distance on the movement characteristics of JPC in *** findings reveal that the head diameter of the JPC increases and experiences significant erosion after entering the water,the effective length of the JPC in water undergoes two distinct phases:a growth phase and a decrease phase,with the velocity of the JPC decaying *** the liner thickness,stand-off distance and the charge aspect ratio can improve the erosion resistance and the velocity retention capacity of the *** optimal ranges for liner thickness and stand-off distance are 0.0363D_(k) to 0.0545D_(k)(D_(k) is the charge diameter),the stand-off distance should be within 1.0D_(k).After the charge aspect ratio higher than 1.25,the charge structure exerts minimal influence the movement characteristics of the JPC in *** density plays a crucial role in the velocity decay pattern of the JPC during *** with higher densities exhibit superior velocity retention capabilities in water,with the velocity decay pattern converging if the densities are ***,copper,tantalum and tungsten liners are deemed appropriate for underwater shaped charge ***,the results will provide an important reference for the design of underwater shaped charge warhead.

关键词： JPC Movement characteristics Underwater penetration Numerical simulation

Adverse Effects of Opioid Analgesics in Osteoarthritis Treatment:A Global Meta-Analysis,2000-2022

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China CDC weekly 2024年第25期6卷 589-596,I0001-I0012页

作者： Heng Jiang xing xing He Zhu Tuo Dong School of Public Health Harbin Medical UniversityHarbin CityHeilongjiang ProvinceChina School of Public Health Peking UniversityBeijingChina

Osteoarthritis(OA)treatment commonly depends on nonsteroidal anti-inflammatory drugs and opioid ***,the clinical use of opioids is controversial due to their adverse effects and addiction *** study,drawing on 24 randomized controlled trials(RCTs)with a total of 9,586 patients,thoroughly explored the various side effects associated with opioid use in OA *** results provide additional insight into the non-addictive risks of opioids and may assist clinicians in their judicious use,potentially fostering the advancement of safer treatment *** reducing the risks of misuse and addiction,public health and safety can be enhanced.

关键词： potential thoroughly insight

Stimuli-evoked NOergic molecules and neuropeptides at acupuncture points and the gracile nucleus contribute to signal transduction of propagated sensation along the meridian through the dorsal medulla-thalamic pathways

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Journal of Integrative Medicine 2024年第5期22卷 515-522页

作者： Sheng-xing Ma Lundquist Institute for Biomedical Innovation Harbor-University of California at Los Angeles (UCLA) Medical Center Department of Obstetrics and Gynecology David Geffen School of Medicine at UCLA and Harbor-UCLA Medical Center

Numerous studies from different international groups have demonstrated that sensations can be propagated along acupuncture channel pathways. The propagated sensation along the channel pathway(PSCP)can be elicited by electroacupuncture(EA), transcutaneous electrical nerve stimulation(TENS), manual acupuncture(MA), and heat applied to distal acupuncture points(acupoints). Nitric oxide(NO) levels were reported to be elevated in the gracile nucleus and skin regions near to the EA sites, with higher levels at acupoints associated with an enhanced expression of NO synthase and transient receptor potential vanilloid type 1. The stimuli, EA, MA, TENS, and heat, have been used to elicit axonal reflexes, which increase local release of NO and neuropeptides such as calcitonin gene related peptide. Furthermore, the sensation of PSCP along the body surface occurs only ipsilaterally to the stimulated acupoints in various human studies, which does not support the involvement of the spinal-thalamic pathway, which would involve cross over transmission of the signals. The gracile nucleus receives ascending input from the sciatic nerve and responds to somatosensory stimulation mainly on the ipsilateral side via the dorsal column pathway. EA at Zusanli(ST36) increases NO release and expression of NO synthase mainly in the ipsilateral side of the gracile nucleus, while the cardiovascular effects and analgesic responses to EA at ST36 are changed by influences of L-arginine-derived NO synthesis in the ipsilateral gracile nucleus in rats. The stimuli-induced release of NOergic molecules and neuropeptides exist high levels in the acupoints, which contain rich neuronal components and blood vessels. Enhanced NOergic molecules at acupoints cause axon reflexes during the stimuli, which elevate cutaneous blood flow. Elevated NOergic molecules and local blood flow may spread over acupoints one after another along the meridian lines differing from nerve pathways following the stimuli to induce PSC

关键词： Axon reflex Biophysical approaches Calcitonin related polypeptide Dorsal funiculus tract Meridian system Nitric oxide