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Infrared Photodissociation Spectroscopy of Ti＋（CO2）2Ar and Ti＋（CO2）n （n=3-7） Complexes

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Chinese Journal of Chemical Physics 2013年第6期26卷 687-693,I0004页

作者： Xiao-peng Xing Guan-jun Wang Cai-xia Wang ming-fei Zhou Department of Chemistry Tongji University Shanghai 200092 China Department of Chemistry Shanghai Key Laboratory of Molecular Catalysts and Innovative MaterialsFudan University Shanghai 200433 China

Ti＋（CO2）2Ar and Ti＋（CO2）n （n=3-7） complexes are produced by laser vaporization in a pulsed supersonic expansion. The ion complexes of interest are each mass-selected in a time- of-flight spectrometer, and studied with infrared photodissociation spectroscopy. For each complex, a sharp band in the CO stretching frequency region is observed, which confirms the formation of the OTi＋CO（CO2）~_l oxide-carbonyl species. Small OTi＋CO（CO2）~_1 complexes （n_〈5） exhibit CO stretching and antisymmetric CO2 stretching vibrational bands that are blue-shifted from those of free CO and CO2. The experimental observations indicate that the coordination number of CO and CO2 molecules around TiO＋ is five. Evidence is also observed for the presence of another electrostatic bonding Ti＋（CO2）2 structural isomer for the Ti＋（CO2）2Ar complex, which is characterized to have a bent OCO-Ti＋-OCO structure stabilized by argon coordination.

关键词： Infrared photodissociation spectroscopy Carbon dioxide complex Titanium Insertion reaction Density functional calculation

Seismological challenges in earthquake hazard reductions:reflections on the 2008 Wenchuan earthquake

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Science Bulletin 2018年第17期63卷 1159-1166页

作者： Yong Chen Jiupeng Hu fei peng School of Earth Sciences and Engineering Nanjing University Institute of Geophysics China Earthquake Administration Seismic Observation and Geophysical Imaging Laboratory Institute of Earthquake Forecasting China Earthquake Administration

The Wenchuan earthquake is a natural disaster. Its occurrence and aftermath have demonstrated the critical roles of seismology and earthquake engineering in reducing seismic hazards and damages. However,their existing limitations should also be underscored. This article summarized and reviewed the current scientific understanding of earthquake ruptures, and new insights gained since the Wenchuan event. This study focused on the related challenges to seismology and earthquake engineering as follows:(1) The under-estimation of earthquake risks before occurrences.(2) The current limited data regarding large earthquakes in continental thrust fault systems.(3) The causal relationship between the Wenchuan earthquake and the reservoir impoundment in its vicinity.(4) The identification of low-velocity zone in the crust and its seismogenical role.(5) The casualties and economic losses from a cascade of diverse natural hazards triggered by the ruptures, and the excellent earthquake resistance associated with tunnels in mountainous terrain.

关键词： Wenchuan earthquake Hazard reduction Low-velocity zone Secondary hazard

Experimental study on the interfacial delamination in a thermal barrier coating system at elevated temperatures

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第10期11卷 794-803页

作者： peng-fei ZHAO Fu-lin SHANG Department of Engineering Mechanics School of Aerospace Xi 'an Jiaotong University Xi 'an 710049 China

The failure mode and adhesion of thermal barrier coating (TBC) 8YSZ (ZrO2+8% (w/w) Y2O3) deposited on NiCoCrAlTaY bond coat by atmospheric plasma spraying were investigated. A grooved modified three-point bending specimen that can generate a single interface crack to facilitate the control of crack growth was adopted for testing, which was conducted at the ambient temperature of 100 °C. The morphology and composition of fractured surfaces were examined by means of a scanning electron microscopy (SEM) and an energy disperse spectroscopy (EDS). Images and spectrum show that cracks are initiated and propagated exclusively within YSZ layer adjacent to top/bond coat interface. The load-displacement curves obtained exhibit similar shapes that indicate two distinct stages in crack initiation and stable crack growth. Finite element analyses were performed to extract the adhesion strength of the TBCs. The delamination toughness of the plasma-sprayed 8YSZ coatings at 100 °C, in terms of critical strain energy release rate Gc, can be reliably obtained from an analytical solution.

关键词： Thermal barrier coating (TBC) Three-point bending test Finite element analysis Delamination toughness

Preparation of selenofunctionalized heterocycles via iodosobenzene-mediated intramolecular selenocyclizations of olefins with diselenides

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Chinese Chemical Letters 2021年第8期32卷 2587-2591页

作者： peng-fei Wang Wei Yi Yong Ling Liang ming Gong-Qing Liu Yu Zhao School of Pharmacy Nantong UniversityNantong 226001China

An intramolecular selenocyclizations of olefins mediated by a commercially available hypervalent iodine(Ⅲ) reagent,PhIO,was *** method provided access to a wide range of selenenylated heterocycles under ambient *** striking advantages of this protocol over all previous methods include mild reaction conditions,easy operation,good yields,high levels of functional group compatibility,large-scale application and suitability for the late-stage functionalization of complex molecules of biological importance.

关键词： Selenocyclizations Olefins Heterocycle Iodosobenzene Diselenides

Mapping global forest biomass and its changes over the first decade of the 21st century

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Science China Earth Sciences 2019年第3期62卷 585-594页

作者： Anping CHEN Shushi peng Songlin fei Department of Forestry and Natural Resources Purdue University The Woods Hole Research Center Laboratoire des Sciences du Climat et de l'Environnement(LSCE) CEA-CNRS-UVSQ

Forests played an important role in carbon sequestration during the past two decades. Using a model tree ensemble method(MTE) to regress the seven reflectance bands of EOS-Terra-MODIS satellite data against country level forest biomass carbon density(BCD) of 2001–2005 provided by United Nations' s Forest Resource Assessment(FRA), we developed a global map of forest BCD at 1 km×1 km resolution for both 2001–2005 and 2006–2010. For 2006–2010, the total global forest biomass carbon stock is estimated as 279.6±7.1 Pg C, and the tropical forest biomass carbon stock is estimated as 174.4±5.4 Pg C. During the first decade of the 21 st century, we estimated an increase of global forest biomass of 0.28±0.75 Pg C yr^(-1). Tropical forest biomass carbon stock slightly decreased(-0.31±0.60 Pg C yr^(-1)); by contrast, temperate and boreal forest biomass increased(0.58±0.28 Pg C yr^(-1)) during the same period. Our estimation of the global forest biomass carbon stock and its changes is subject to uncertainties due to lack of extensive ground measurements in the tropics, spatial heterogeneity in large countries, and different definitions of forest. The continuously monitoring of forest biomass carbon stock with MODIS satellite data will provide useful information for detecting forest changes.

关键词： Forest biomass Carbon stock Model tree ensemble(MTE) MODIS Remote sensing

Variations in soil moisture over the ‘Huang-Huai-Hai Plain＇ in China due to temperature change using the CNOP-P method and outputs from CMIP5

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Science China Earth Sciences 2017年第10期60卷 1838-1853页

作者： SUN GuoDong peng fei MU Mu State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Institute of Atmospheric Sciences Fudan University Shanghai 200433 China University of Chinese Academy of Sciences Beijing 100049 China Numerical Weather Prediction Center China Meteorological Administration Beijing 100081 China

In this study, the variations in surface soil liquid water(SSLW) due to future climate change are explored in the‘Huang-Huai-Hai Plain'(‘3H') region in China with the Common Land Model(CoLM). To evaluate the possible maximum response of SSLW to climate change, the combination of the conditional nonlinear optimal perturbation related to the parameter(CNOP-P) approach and projections from 10 general circulation models(GCMs) of the Coupled Model Intercomparison Project5(CMIP5) are used. The CNOP-P-type temperature change scenario, a new type of temperature change scenario, is determined by using the CNOP-P method and constrained by the temperature change projections from the 10 GCMs under a high-emission scenario(the Representative Concentration Pathway 8.5 scenario). Numerical results have shown that the response of SSLW to the CNOP-P-type temperature scenario is stronger than those to the 11 temperature scenarios derived from the 10 GCMs and from their ensemble average in the entire ‘3H' region. In the northern region, SSLW under the CNOP-P-type scenario increases to0.1773 m^3 m^(-3); however, SSLW in the scenarios from the GCMs fluctuates from 0.1671 to 0.1748 m^3 m^(-3). In the southern region,SSLW decreases, and its variation(–0.0070 m^3 m^(-3)) due to the CNOP-P-type scenario is higher than each of the variations(–0.0051 to –0.0026 m^3 m^(-3)) due to the scenarios from the GCMs.

关键词： CNOP-P Surface soil liquid water CMIP5 Climate change Seasonal and regional heterogeneity

A Novel Through-the-Wall Imaging Algorithm Combined with Phase Shift Migration and NUFFT

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Chinese Journal of Electronics 2017年第5期26卷 1096-1100页

作者： ZHANG peng fei peng WEN Xin NIAN Feng Institute of Radio Metrology and Measurement

This paper proposes a novel Through wall imaging(TWI) algorithm combined with phase compensation and Nonuniform fast Fourier transform(NUFFT).The wall effect is cancelled with phase compensation,which is implemented by multiplying the conjugated wall transmissivity with the received *** NUFFT technique is implemented to calculate the imaging *** proposed method has two merits:The phase compensation avoids a time-consuming calculation of the incidences angles;the image is reconstructed more accurately and efficiently than the conventional Interpolation-fast Fourier transform(IPFFT) *** new method is implemented on 2D synthetic-generated data and experimental *** results demonstrate that our method generates high quality focused images and achieves target geometrical identification within a very short time.

关键词： Phase shift migration(PSM) Nonuniform Fourier transform(NUFFT) Through-the-wall imaging(TWI)

Coupling of RANS and BEM Solvers for Simulation of Propeller Behind the Hull in Full Appended Model

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China Ocean Engineering 2024年第3期38卷 424-438页

作者： Saeed NAJAFI Mehdi POURMOSTAFA LIU peng-fei Iranian National Institute for Oceanography and Atmospheric Science(INIOAS) Tehran 14155-4781Iran Department of Maritime Engineering Amir Kabir University of TechnologyTehran 15875-4413Iran Marine Offshore and Subsea TechnologySchool of EngineeringNewcastle UniversityNewcastle upon TyneNE17RUUK

To design a propeller for ship power plant,the interaction between ship hull and propeller must be taken into *** main concern is to apply the wake effect of ship stern on the propeller *** this paper,a coupled BEM(Boundary Element Method)/RANS(Renolds-Averaged Navier−Stokes)solver is used to simulate propeller behind the hull in the self-propulsion *** motivation of this work is to develop a practical tool to design marine propulsion system without suffering long computational *** unsteady boundary element method which is also known as panel method is chosen to estimate the propeller *** wakes are treated using a time marching wake alignment ***,a RANS code coupled with VoF equation is developed to consider the ship motions and wake field effects in the problem.A coupling algorithm is developed to interchange ship wake field to the potential flow solver and propeller thrust to the RANS *** on the difference between hull resistance and the propeller thrust,a PI controller is developed to compute the propeller RPM in every time *** of the solver is carried out using the towing tank test report of a 50 m oceanography research *** factor and trust deduction coefficient are estimated ***,the wake rollup pattern of the propeller in open water is compared with the propeller in real wake field.

关键词： RANS BEM coupled method ship propeller self-propulsion wake sheet pattern

Heparin is an effective treatment for preventing liver failure after hepatectomy

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World Journal of Gastroenterology 2024年第22期30卷 2881-2892页

作者： Zhi-Ying Xu Min peng ming-ming Fan Qi-fei Zou Yi-Ran Li Dong Jiang Hepatic Surgery IV Shanghai Eastern Hepatobiliary Surgery HospitalThe Third Affiliated Hospital of Naval Medical UniversityShanghai 200433China Ultrasound Diagnosis PLA Naval Medical CenterShanghai 200437China Department of Ultrasound Eastern Hepatobiliary Surgery HospitalThe Third Affiliated Hospital of Naval Medical UniversityShanghai 200433China

BACKGROUND Posthepatectomy liver failure(PHLF)is one of the most important causes of death following liver ***,an established anticoagulant,can protect liver function through a number of mechanisms,and thus,prevent liver *** To look at the safety and efficacy of heparin in preventing hepatic dysfunction after *** The data was extracted from Multiparameter Intelligent Monitoring in Intensive Care III(MIMIC-III)v1.4 pinpointed patients who had undergone hepatectomy for liver cancer,subdividing them into two cohorts:Those who were injected with heparin and those who were *** statistical evaluations used were unpaired ttests,Mann-Whitney U tests,chi-square tests,and Fisher’s exact tests to assess the effect of heparin administration on PHLF,duration of intensive care unit(ICU)stay,need for mechanical ventilation,use of continuous renal replacement therapy(CRRT),incidence of hypoxemia,development of acute kidney injury,and ICU *** regression was utilized to analyze the factors related to PHLF,with propensity score matching(PSM)aiming to balance the preoperative disparities between the two *** In this study,1388 patients who underwent liver cancer hepatectomy were *** yielded 213 matched pairs from the heparin-treated and control *** univariate analyses indicated that heparin potentially reduces the risk of PHLF in both matched and unmatched *** analysis in the matched cohorts confirmed a significant association,with heparin reducing the risk of PHLF(odds ratio:0.518;95%confidence interval:0.295-0.910;P=0.022).Additionally,heparin treatment correlated with improved short-term postoperative outcomes such as reduced ICU stay durations,diminished requirements for respiratory support and CRRT,and lower incidences of hypoxemia and ICU *** Liver failure is an important hazard following hepatic *** ICU care heparin administration has been proved to decr

关键词： Liver resection Posthepatectomy liver failure Prophylactic treatment Heparin Prognosis of hepatectomy