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The monitoring and analysis of the coastal lowland subsidence in the southern Hangzhou Bay with an advanced time-series InSAR method

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Acta Oceanologica Sinica 2017年第7期36卷 110-118页

作者： HAN peng YANG Xiaoxia bai Lin SUN Qishi Administrative Center for China's Agenda 21 Beijing 100038China College of Earth Science Chengdu University of TechnologyChengdu 610059China Key Laboratory of Geoscience Spatial Information Technology of Ministry of Land and Resources Chengdu University of TechnologyChengdu 610059China College of Earth Sciences University of Chinese Academy of SciencesBeijing 100049China

Time-series InSAR analysis（e.g., permanent scatterers（PSInSAR）） has been proven as an effective technology in monitoring ground deformation over urban areas. However, it is a big challenge to apply this technology in coastal regions due to the lack of man-made targets. An distributed scatterers interferometric synthetic aperture radar（DSInSAR） is developed to solve the problem of insufficient samples and low reliability in monitoring coastal lowland subsidence, by applying a spatially adaptive filter and an eigendecomposition algorithm to estimating the optimal phase of statistically homogeneous distributed scatterers（DSs）. Twenty-four scenes of COSMO-Sky Med images acquired between 2013 and 2015 are used to retrieve the land subsidence over the Shangyu District on south coast of the Hangzhou Bay, Zhejiang Province, China. The spatial pattern of the land subsidence obtained by the PS-InSAR and the DSInSAR coincides with each other, but the density of the DSs is three point five times higher than the permanent scatterers（PSs）. Validated by precise levelling data over the same period, the DSInSAR method achieves an accuracy of ±5.0 mm/a which is superior to the PS-InSAR with±5.5 mm/a. The land subsidence in the Shangyu District is mainly distributed in the urban areas, industrial towns and land reclamation zones, with a maximum subsidence rate -30.2 mm/a. The analysis of geological data, field investigation and historical reclamation data indicates that human activities and natural compaction of reclamation material are major causes of the detected land subsidence. The results demonstrate that the DSInSAR method has a great potential in monitoring the coastal lowland subsidence and can be used to further investigate subsidence-related environmental issues in coastal regions.

关键词： coastal areas land subsidence DSInSAR PSInSAR leveling observation Hangzhou Bay in China

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Tidal energy budget in the Zhujiang(Pearl River) Estuary

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Acta Oceanologica Sinica 2016年第5期35卷 54-65页

作者： bai peng GU Yanzhen LI Peiliang WU Kejian Physical Oceanography Laboratory Ocean University of China College of Information Science and Engineering Ocean University of China

Tidal energy budget in the Zhujiang（Pearl River） Estuary（ZE） is evaluated by employing high-resolution baroclinic regional ocean modeling system（ROMS）. The results obtained via applying the least square method on the model elevations are compared against the tidal harmonic constants at 18 tide stations along the ZE and its adjacent coast. The mean absolute errors between the simulation and the observation of M_2, S_2, K_1 and O_1 are 4.6, 2.8, 3.2 and 2.8 cm in amplitudes and 9.8°, 15.0°, 4.6° and 4.6° in phase-lags, respectively. The comparisons between the simulated and observed sea level heights at 11 tide gauge stations also suggest good model performance. The total tidal energy flux incoming the ZE is estimated to be 343.49 MW in the dry season and larger than 336.18 MW in the wet season, which should due to higher mean sea level height and heavier density in the dry season. M_2, K_1, S_2, O_1 and N_2, the top five barotropic tidal energy flux contributors for the ZE,import 242.23（236.79）, 52.97（52.08）, 24.49（23.96）, 16.22（15.91） and 7.10（6.97） MW energy flux into the ZE in dry（wet） season, successively and respectively. The enhanced turbulent mixing induced by eddies around isolated islands and sharp headlands dominated by bottom friction, interaction between tidal currents and sill topography or constricted narrow waterways together account for the five energy dissipation hotspots, which add up to about 38% of the total energy dissipation inside the ZE.

关键词： tidal energy flux energy dissipation Zhujiang Estuary regional ocean modeling system

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Direct Coupling Reaction of Diaryl Methanol with Ketones or Aldehydes Catalyzed by AlCl_(3)

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Chinese Journal of Chemistry 2014年第11期32卷 1176-1182页

作者： zhiqiang Zhu peng bai Tiantian Wang zhizhen Huang Department of Chemistry Zhejiang UniversityHangzhouZhejiang 310028China State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China

A novel coupling reaction of diaryl methanols with ketones or aldehydes has been developed under the catalysis of AlCl_(3).Various ketones and aldehydes could couple with 9H-xanthen-9-ol smoothly,affording coupling products in 48%-88%yields.A plausible mechanism using AlCl_(3) to activate both diaryl methanol and ketone or aldehyde is proposed.

关键词： coupling reaction alcohol ketone aldehyde AlCl_(3) catalysis

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Hydrogen production by steam reforming of acetic acid and bio-oil using Ni/γ-Al2O3 catalysts

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International Journal of Agricultural and Biological Engineering 2015年第6期8卷 69-76页

作者： Li Yanmei Fu peng Yi Weiming bai Xueyuan School of Agricultural and Food Engineering Shandong University of TechnologyZiboShandong 255049China Shandong Research Center of Engineering and Technology for Clean Energy ZiboShandong 255049China

Hydrogen production from steam reforming of bio-oil and acetic acid using Ni/γ-Al2O3 catalyst was studied in a laboratory-scale fixed bed *** study selected different Ni loadings(16.8%and 30.5%)in Ni/γ-Al2O3 catalysts and reaction temperatures(500°C,600°C and 700°C)as variables to optimize the hydrogen yield and selectivity of gases *** were carried out in an isothermal *** catalysts were prepared on wet impregnation of aγ-Al2O3 which supported with two different Ni *** principal gases generated were H2,CO,CO2 and *** results from steam reforming of acetic acid showed that the yield and selectivity of hydrogen using the catalyst with 30.5%Ni were significantly higher than that with 16.8%*** results showed that the most favorable temperature for hydrogen production was 600°C,and the steam reforming of bio-oil using Ni/γ-Al2O3 catalyst with 30.5%Ni showed that the yields and selectivity of H2 and CO2 increased with the temperature increasing while CH4 and CO selectivity *** results showed that the most favorable temperature for hydrogen production from bio-oil using 30.5%Ni/γ-Al2O3 was 600°C,at which hydrogen yield was at its maximum of 65%.

关键词： hydrogen bio-oil Ni/γ-Al2O3 catalyst steam reforming acetic acid

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A pharmacological approach to study the active compounds in Jinshui Huanxian formula in treatment of pulmonary fibrosis

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Journal of Traditional Chinese Medicine 2019年第3期39卷 364-379页

作者： bai Yunping Zhao peng Wu Mingming Li Jiansheng Collaborative Innovation Center for Respiratory Disease Diagnosis and Treatment & Chinese Medicine Development of Henan Province Henan University of Chinese MedicineZhengzhou 450046 China Henan Key Laboratory of Chinese Medicine for Respiratory Disease Henan University of Chinese Medicine Zhengzhou 450046 China

OBJECTIVE:To study the active compounds in Jinshui Huanxian formula in the treatment of pulmonary fibrosis with a pharmacological ***:A systems pharmacology model,incorporating active compounds and targets prediction,and herbal-comPound-target-disease network analysis,was established to predict the active substances and therapeutic mechanisms of Jinshui Huanxian *** compounds from the herbs of Jinshui Huanxian formula were obtained from drug database and the ***,we analyzed the potential of herbs by predicting oral bioavailability and drug-likeness *** compounds with oral bioavailability≥ 30% and drug-likeness index ≥ 0.18 were obtained as candidate compounds for further *** then used the systematic drug targeting tool to screen the targets for candidate *** potential targets were projected into Therapeutic Target Database to collect their corresponding *** candidate compounds,potential targets and their related diseases were applied to construct the compound-target and target-disease ***:Totally 136 compounds from Jinshui Huanxian formula and 265 potential targets were ***-target network analysis suggested that different herbal drugs contained in the Jinshui Huanxian formula could regulate these similar targets to probably exert synergistic ***,target proteins were mainly related to oxidoreductase activity,nicotinamide adenine dinucleotide phosphate binding,and G-protein coupled amine receptor activity,which might be associated with the therapeutic mechanisms of Jinshui Huanxian *** addition,Jinshui Huanxian formula was probably efficient for many different diseases,such as respiratory tract diseases,neoplasm,nervous system diseases,and cardiovascular diseases,according to target-disease ***:This study may provide a method to explore the potential active compounds in Jinshui Huanxian formula used to treat pulmonary fibrosis.

关键词： Pulmonary fibrosis Pharmacology Jinshui Huanxian formula

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Observation of the supercritical Pearl River plume front under the downwelling-favorable winds

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Science China Earth Sciences 2015年第11期58卷 2059-2066页

作者： bai peng GU YanZhen LUO Lin ZHANG WanLei FAN KaiGuo College of Physical and Environmental Oceanography Ocean University of China College of Information Science and Engineering Ocean University of China Institute of Space and Earth Information Science Chinese University of Hong Kong State Key Laboratory of Tropical Oceanography South China Sea Institute of Oceanology Chinese Academy of Sciences Qinhuangdao Marine Environmental Monitoring Central Station of SOA 91039 Army PLA

For the Pearl River plume, the supercritical, distinct plume front appears in downwelling-favorable winds, which is easily observed due to the distinct boundary between the plume water and the ambient water. In this paper, in situ and satellite observations of a plume front are utilized to explore the Pearl River plume front properties under the downwelling-favorable winds. Field observations clearly show frontal structure, especially the two-layer structure in the plume water and the downward-motion of water in the frontal region. The Advanced Synthetic Aperture Radar(ASAR) images are also analyzed to unveil the plume front: there is a white stripe on the west side out of the river mouth under downwelling-favorable winds, which is identified as a supercritical plume front, and the width of the plume front is about 250 m. The normalized velocity gradient shows the intense velocity convergence in the front region. Also, analyses of ASAR images imply that the river discharge plays an important role in controlling the location and shape of the front.

关键词： cruise observations Pearl River plume front ASAR winds

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Palladium-catalyzed relay C–H functionalization to construct novel hybrid-arylcyclophosphorus ligand precursors

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Chinese Chemical Letters 2022年第5期33卷 2397-2401页

作者： Juan Wang peng-Bo bai Shang-Dong Yang State Key Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhou 730000China State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

A new relay C–H functionalization of di([1,1'-biphenyl]-2-yl)phosphine oxide to obtain esterified and hy-droxylated products with different hypervalent iodines as oxidants under palladium catalysis is *** reaction provides a more effective and concise strategy for the synthesis of novel structural hybrid-arylcyclophosphorus ligand precursors with a wide range of substrates and good functional group toler-ance.

关键词： Palladium catalyst Cyclization Acetylation Hydroxylation Dibenzophosphorus oxide

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A model for accurately calculating hyper-spectral, middle-shortwave infrared radiative transfer for remote sensing

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Science China Earth Sciences 2018年第3期61卷 317-326页

作者： bai WenGuang ZHANG peng ZHANG WenJian MA Gang QI ChengLi School of Atmosphere Physics Nanjing University of Information Science & Technology Nanjing 210044 China National Satellite Meteorology Center Beijing 100081 China

Although the calculation of radiative transfer in the middle-shortwave infrared band is important in the field of optical remote sensing, studies in this area of research are rare in China. Both solar reflection and atmospheric emission should be considered when calculating radiative transfer in the middle-shortwave infrared band. This paper presents a new radiative transfer model based on the doubling and adding method. The new model uses approximate calculations of direct solar reflection,multiple scattering, and thermal emissions for a finitely thin atmospheric layer and considers both the solar and thermal sources of radiation. To verify its accuracy, the calculation results produced by the model for four typical scenarios(single layer at night,multi-layer aerosols, double-layer with ice and water clouds, and multi-layer with clouds and aerosols) were compared with those of the DISORT model. With the exception of a few channels, the absolute deviation between the two models was less than2×10^(-6) K. For the same calculation, the computation speed of the new model was approximately two to three times faster than that of the DISORT model. Sensitivity studies were performed to evaluate the error resulting from using simplified calculation methods in the new model. The results obtained in this study indicated that atmospheric thermal emission made a significant contribution to the measured radiance in the strong-absorption band(2230–2400 cm^(-1)), whereas solar radiation could be neglected in this region. However, neglecting solar radiation in the window region(2400–2580 cm^(-1)) introduced error on the order of dozens of K. Employing the average-layer temperature method simplified the calculation of thermal radiation but caused a larger error in the strong-absorption band than in the window region. In the doubling and adding method, the calculation error decreased as the value used for minimum optical thickness decreased. Under the condition of satisfying the requi

关键词： Doubling and adding method Radiative transfer calculation Middle-shortwave infrared band Light scattering byclouds and aerosols

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Saturation phenomenon of Ce and Ti in the modification of Al–Zn–Si filler metal

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International Journal of Minerals,Metallurgy and Materials 2015年第2期22卷 184-189页

作者： Jin-long Yang Song-bai Xue Wei Dai peng Xue College of Materials Science and Technology Nanjing University of Aeronautics and Astronautics Zhejiang Xinrui Welding Material Co. Ltd.

Cerium and titanium were added to an A1-42Zn-5.5Si brazing alloy, and the subsequent microstructures of the brazing alloy and the 6061 AI alloy brazing seam were investigated. The microstructures of filler metals and brazed joints were characterized by scanning elec- tron microscopy and X-ray energy dispersion spectrometry. A new Ce-Ti phase formed around the silicon phase in the modified filler metal and this saturation phenomenon was analyzed. Interestingly, following brazing of the 6061 alloy, there is no evidence of the Ce--Ti phase in the brazing seam. Because of the mutual solubility of the brazing alloy and base metal, the quantity of the solvent increases, and the solute Ce and Ti atoms assume an undersaturated state.

关键词： filler metals aluminum alloys brazing cerium titanium saturation

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Experiment on Wear Behavior of High Pressure Gas Seal Faces

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Chinese Journal of Mechanical Engineering 2014年第6期27卷 1287-1293页

作者： XU Jing peng Xudong bai Shaoxian MENG Xiangkai LI Jiyun MOE Engineering Research Center of Process Equipment and Its Remanufacture Zhejiang University of Technology School of Mechanical Engineering Hangzhou Dianzi University

Current researches show that mechanical deformation of seal ring face makes fluid film clearance decrease at high pressure side, thus a divergent clearance is formed and face wear occurs more seriously at the high pressure side than that on the low pressure side. However, there is still lack of published experimental works enough to prove the theoretical results. In this paper, a spiral groove dry gas seal at high pressures is experimentally investigated so as to prove the face wear happened at the high pressure side of seal faces due to the face mechanical deformation, and the wear behavior affected by seal ring structure is also studied. The experimental results show that face wear would occur at the high pressure side of seal faces due to the deformation, thus the leakage and face temperature increase, which all satisfies the theoretical predictions. When sealed pressure is not less than 5 MPa, the pressure can provide enough opening force to separate the seal faces. The seal ring sizes have obvious influence on face wear. Face wear, leakage and face temperature of a dry gas seal with the smaller cross sectional area of seal ring are less than that of a dry gas seal with bigger one, and the difference of leakage rate between these two sizes of seal face width is in the range of 24%–25%. Compared with the effect of seal ring sizes, the effect of secondary O-ring seal position on face deformation and face wear is less. The differences between these two types of dry gas seals with different secondary O-ring seal positions are less than 5.9% when the rotational speed varies from 0 to 600 r/min. By linking face wear and sealing performance changes to the shift in mechanical deformation of seal ring, this research presents an important experimental method to study face deformation of a dry gas seal at high pressures.

关键词： dry gas seal structures face wear high pressure mechanical deformation

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