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A sulfur-tolerant Pd/CeO_2 catalyst for methanol synthesis from syngas

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Journal of Natural Gas Chemistry 2008年第4期17卷 387-390页

作者： Yuchun Ma qingjie Ge Wenzhao li Hengyong Xu Laboratory of Applied Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 Liaoning China

The catalytic activity of ceria-supported Pd for selective hydrogenation of CO is well preserved in the presence of 30 ppm H2S due to the parallel oxidation of sulfur by CeO2 under standard methanol synthesis conditions. The bifunctional nature of this catalyst opens a route for the conversion of sulfur-contaminated gas streams such as the integrated gasification combined cycle syngas or biogas into liquid fuels if desulfurization by conventional means is not practical.

关键词： sulfur-tolerant catalysis Pd catalyst methanol synthesis

Evaluating the Accuracy of ERA5 Wave Reanalysis in the Water Around China

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Journal of Ocean University of China 2021年第1期20卷 1-9页

作者： SHI Hongyuan CAO Xuefeng li qingjie li Delei SUN Jiacheng YOU Zaijin SUN Qingying School of Civil Engineering Ludong UniversityYantai 264025China Institute of Ports and Coastal Disaster Mitigation Ludong UniversityYantai 264025China National Marine Environmental Monitoring Center Dalian 116023China Yantai Marine Environmental Monitoring Central Station State Oceanic AdministrationYantai 264006China Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao 266071China

Wave parameters, such as wave height and wave period, are important for human activities, such as navigation, ocean engineering and sediment transport, etc. In this study, wave data from six buoys around Chinese waters, are used to assess the quality of wave height and wave period in the ERA5 reanalysis of the European Centre for Medium-Range Weather Forecasts. Annual hourly data with temporal resolution are used. The difference between the significant wave height(SWH) of ERA 5 and that of the buoy varies from-0.35 m to 0.30 m for the three shallow locations;for the three deep locations, the variation ranges from-0.09 m to 0.09 m. The ERA5 SWH data show positive biases, indicating an overall overestimation for all locations, except for E2 and S1 where underestimation is observed. During the tropical cyclone period, a large(about 32%) underestimation of the maximum SWH in the ERA5 data is observed. Hence, the ERA5 SWH data cannot be used for design applications without site-specific validation. The difference between the annual wave period from ERA5 and the mean wave period from the buoys varies from-1.31 s to 0.4 s. Inter-comparisons suggest that the ERA5 dataset is consistent with the annual mean SWH. However, for the average period, the performance is not good, and half of the correlation coefficients in the four points are less 50%. Overall, the deep water area simulation effect is better than that in the shallow water.

关键词： wave hindcasting reanalysis ERA5 wave height wave period

The Influence of Sea Sprays on Drag Coefficient at High Wind Speed

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Journal of Ocean University of China 2023年第1期22卷 21-27页

作者： SHI Hongyuan li qingjie WANG Zhaowei ZHANG Xuri li Huaqing XING Hao ZHANG Kuncheng Centre for Ports and Coastal Disaster Mitigation Ludong UniversityYantai 264025China The Center for Ports and Maritime Safety(CPMS) Dalian Maritime UniversityDalian 1160263China Marine Environmental Monitoring Central Station State Oceanic AdministrationYantai 264025China Guangxi Key Laboratory of Marine Environmental Science Guangxi Academy of SciencesNanning 530025China

Field and laboratory observations indicate that the variation of drag coefficient with wind speed at high winds is different from that under low-to-moderate *** taking the effects of wave development and sea spray into account,a new parameterization of drag coefficient applicable from low to extreme winds is *** is shown that,under low-to-moderate wind conditions so that the sea spray effects could be neglected,the nondimensional aerodynamic roughness first increases and then decreases with the increasing wave age;whereas under high wind conditions,the drag coefficient decreases with the increasing wind speed due to the modification of the logarithmic wind profile by the effect of sea spray droplets produced by bursting bubbles or wind tearing breaking wave *** drag coefficients and sea surface aerodynamic roughnesses reach their maximum values vary under different wave ***,the reduction of drag coefficient under high winds reduces the increasing rate of friction velocity with increasing wind speed.

关键词： sea spray wave age drag coefficient high wind speed

Simulation and Analysis of Back Siltation in a Navigation Channel Using MIKE 21

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Journal of Ocean University of China 2022年第4期21卷 893-902页

作者： ZHANG Kuncheng li qingjie ZHANG Jing SHI Hongyuan YU Jing GUO Xinchang DU Yonggang School of Marxism/Institute of Marine Development Ocean University of ChinaQingdao 266100China Guangxi Key Laboratory of Marine Environmental Science Guangxi Academy of SciencesGuangxi 530007China Yantai Marine Environment Monitoring Center Station State Oceanic AdministrationYantai 264006China Qingdao Ocean Shipping Mariners College Teaching and Research Department of Mathematics and Computer ScienceQingdao 266100China Civil Engineering College Ludong UniversityYantai 264025China College of Oceanic and Atmospheric Sciences/Institute of Marine Development Ocean University of ChinaQingdao266100China

The channel back-siltation problem has been restricting the development of channels,and its monitoring is limited by funds and natural ***,predicting the channel back-siltation situation in a timely and accurate manner is ***,a numerical simulation of the back-siltation problem in the sea area near the channel is of great significance to the maintenance of a *** this study,the back siltation of a deep-water channel in the Lanshan Port area of the Port of Rizhao after dredging is *** paper relies on the MIKE 21 software to establish the wave,tidal current,and sediment numerical models and uses measured data from two observation stations in the study area for *** this basis,taking one month as an example,the entire project channel was divided into five sections,and three observation points were set on each *** results show that the area with offshore siltation is located in the northerly direction of the artificial anti-wave *** occurred on the northern seabed in the sea a little farther from the *** occurred on the seabed surface far away from the shoreline,and with the increase in the distance from the shoreline,the amount of siltation in the south,center,and north became gradually closed,and the results can be used to guide actual engineering *** study will play a positive role in promoting the dredging project of Rizhao Lanshan Port.

关键词： channel back siltation numerical simulation back silting analysis and prediction

Variation of Yellow River Runoff and Its Influence on Salinity in Laizhou Bay

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Journal of Ocean University of China 2020年第6期19卷 1235-1244页

作者： SHI Hongyuan li qingjie SUN Jiacheng GAO Guandong SUI Yi QIAO Shouwen YOU Zaijin School of Civil Engineering Ludong UniversityYantai 264025China Institute of Ports and Coastal Disaster Mitigation Ludong UniversityYantai 264025China Marine Environmental Monitoring Central Station SOAYantai 264025China Key Laboratory of Ocean Circulation and Waves Institute of Oceanology Chinese Academy of SciencesQingdao 266071China Qingdao National Laboratory for Marine Science and Technology Qingdao 266000China Center for Mega Science Chinese Academy of ScienceQingdao 266071China

Salinity in estuaries has an important influence on sediment deposition,delta formation,and fishery *** change of runoff in Yellow River(YR),which is the largest river along the Bohai Sea,has an important effect on the salinity of the sea,particularly in Laizhou *** this study,measured runoff data in lijin hydrological station from 1950 to 2018 are adopted to examine the change of YR runoff into the *** study concludes that the runoff of YR is distributed unevenly throughout the year and the amount of runoff mainly concentrates during the flood *** show a decreasing trend at a significant level ofα=0.95,with a range of−6.17×10^9 m^3 yr−*** groups of runoff are set by using the Finite-Volume Coastal Ocean Model numerical model to analyze the change of salinity in Laizhou *** modeled effects were compared with water level observations made by Bayuquan,Tanggu,and Penglai gauge stations and salinity surveys conducted by Longkou gauge *** results and observations of salinity distributions and coastal water level showed good *** can conclude that the distribution of salinity in Laizhou Bay is high in the east and low in the ***,it responded quickly to the change of the runoff from *** conditions of high river discharge,the low-salinity zone increased in horizontal direction and reached the bottom in vertical direction.

关键词： Yellow River runoff salinity FVCOM Laizhou Bay

Abundance and characteristics of microplastics in shellfi sh from Jiaozhou Bay,China

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Journal of Oceanology and limnology 2022年第1期40卷 163-172页

作者： Kangning ZHANG Junhua liANG Tao liU qingjie li Mingliang ZHU Shan ZHENG Xiaoxia SUN Jiaozhou Bay National Marine Ecosystem Research Station Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Ecology and Environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Center for Ocean Mega-Science Institute of OceanologyChinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China

As an emerging pollutant,the presence of microplastics in marine organisms has been concerned *** sh,which are both economically and ecologically important,are of particular *** this study,we investigated the microplastic pollution in wild and farmed oysters(Crassostrea gigas)and clams(Ruditapes philippinarum)in the Jiaozhou Bay,China,for the fi rst *** found the microplastic pollution in shellfi sh in Jiaozhou Bay was at a moderate *** abundance of microplastics in shellfi sh ranged from 0.16 to 12.09 items/g(wet weight,ww)or 1 to 9 items/*** average abundance of the ingested microplastics was 1.21 items/g(or 2.17 items/ind.)in all shellfi sh,1.51 items/g(or 2.00 items/ind.)in clams and 0.92 items/g(or 2.34 items/ind.)in *** abundance of microplastics in clams was signifi cantly higher than that in *** microplastics(92.97%)were fi bers,followed by *** predominant color of the microplastics was black(42.97%),followed by blue,transparent,and *** and polyethylene terephthalate(PET)dominated the microplastic *** to shellfi sh consumption,it can be inferred that the average microplastic consumption through Chinese diet is 1.27×10^(3)items per capita per year.

关键词： microplastics bivalves Jiaozhou Bay risk assessment

Effect of Reduction Temperature on Hydrofining Performance of Supported Molybdenum Phosphide Catalyst

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Journal of Natural Gas Chemistry 2005年第4期14卷 233-237页

作者： Fengyan li Zhifang Zhao qingjie li Tianbo Zhao Cuiqing li Guida Sun Department of Applied Chemistry Beijing Institute of Petrochemical Technology Beijing 102617 China School of Science Beijing Institute of Technology Beijing 100081 China

A series of supported molybdenum phosphide catalysts were prepared by impregnation method. XRD, TG-DTG, XPS and BET were used to study the phase, compositions and surface areas of the prepared catalysts. A model reactant containing thiophene, pyridine and cyclohexene was used for the measurements of catalytic activities. The effect of reduction temperature on catalytic activities was investigated. The analysis results by XRD and BET are very different when the reduction temperature is changed from 400 to 900 ℃. MoP/γ-Al2O3 catalysts and CoMoP/γ-Al2O3 catalysts prepared at the reduction temperature of 500 ℃ are the most active ones.

关键词： molybdenum phosphide reduction temperature hydrodenitrogenation hydrodesulfurization supported catalyst

Interleukin-27 decreases ghrelin production through signal transducer and activator of transcription 3—mechanistic target of rapamycin signaling

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Acta Pharmaceutica Sinica B 2020年第5期10卷 837-849页

作者： Heng Zhang qingjie li Yuxin Teng Yubi lin Shaojian li Tingfeng Qin linxi Chen Jiana Huang Hening Zhai Quan Yu Geyang Xu Department of Physiology School of MedicineJinan UniversityGuangzhou 510632China Department of Cardiology and Cardiovascular Intervention Interventional Medical Centerthe Fifth Affiliated Hospital of Sun Yat-sen UniversityZhuhai 519000China Endoscopy Center the First Affiliated Hospital of Jinan UniversityGuangzhou 510630China Central Laboratory School of MedicineJinan UniversityGuangzhou 510632China

Interleukin-27(IL-27),a heterodimeric cytokine,plays a protective role in ***,a gastric hormone,provides a hunger signal to the central nervous system to stimulate food *** relationship between IL-27 and ghrelin is still *** we investigated that signal transducer and activator of transcription 3(STAT3)—mechanistic target of rapamycin(mTOR)signaling mediates the suppression of ghrelin induced by ***-localization of interleukin 27 receptor subunit alpha(WSX-1)and ghrelin was observed in mouse and human gastric *** injection of IL-27 markedly suppressed ghrelin synthesis and secretion while stimulating STAT3-mTOR signaling in both C57 BL/6 J mice and high-fat diet-induced-obese ***-27 inhibited the production of ghrelin in mHypoE-N42 *** of mTOR activity induced by mTOR siRNA or rapamycin blocked the suppression of ghrelin production induced by IL-27 in mHypoE-N42 *** 3 siRNA also abolished the inhibitory effect of IL-27 on ***-27 increased the interaction between STAT3 and mTOR in mHypoE-N42 *** conclusion,IL-27 suppresses ghrelin production through the STAT3-mTOR dependent mechanism.

关键词： IL-27 Ghrelin STAT3 mTOR Food intake

DDoS Attack Autonomous Detection Model Based on Multi-Strategy Integrate Zebra Optimization Algorithm

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Computers, Materials & Continua 2025年第1期82卷 645-674页

作者： Chunhui li Xiaoying Wang qingjie Zhang Jiaye liang Aijing Zhang School of Information Engineering Institute of Disaster PreventionLangfang065201China Langfang Key Laboratory of Network Emergency Protection and Network Security Langfang065201China

Previous studies have shown that deep learning is very effective in detecting known ***,when facing unknown attacks,models such as Deep Neural Networks(DNN)combined with Long Short-Term Memory(LSTM),Convolutional Neural Networks(CNN)combined with LSTM,and so on are built by simple stacking,which has the problems of feature loss,low efficiency,and low ***,this paper proposes an autonomous detectionmodel for Distributed Denial of Service attacks,Multi-Scale Convolutional Neural Network-Bidirectional Gated Recurrent Units-Single Headed Attention(MSCNN-BiGRU-SHA),which is based on a Multistrategy Integrated Zebra Optimization Algorithm(MI-ZOA).The model undergoes training and testing with the CICDDoS2019 dataset,and its performance is evaluated on a new GINKS2023 *** hyperparameters for Conv_filter and GRU_unit are optimized using the Multi-strategy Integrated Zebra Optimization Algorithm(MIZOA).The experimental results show that the test accuracy of the MSCNN-BiGRU-SHA model based on the MIZOA proposed in this paper is as high as 0.9971 in the CICDDoS 2019 *** evaluation accuracy of the new dataset GINKS2023 created in this paper is *** to the MSCNN-BiGRU-SHA model based on the Zebra Optimization Algorithm(ZOA),the detection accuracy on the GINKS2023 dataset has improved by 5.81%,precisionhas increasedby 1.35%,the recallhas improvedby 9%,and theF1scorehas increasedby 5.55%.Compared to the MSCNN-BiGRU-SHA models developed using Grid Search,Random Search,and Bayesian Optimization,the MSCNN-BiGRU-SHA model optimized with the MI-ZOA exhibits better performance in terms of accuracy,precision,recall,and F1 score.

关键词： Distributed denial of service attack intrusion detection deep learning zebra optimization algorithm multi-strategy integrated zebra optimization algorithm