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Growth characteristics of directionally solidified Al_2O_3/YAG/ZrO_2 ternary hypereutectic in situ composites under ultra-high temperature gradient

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International Journal of Minerals,Metallurgy and Materials 2011年第1期18卷 121-125页

作者： Hai-jun Su Jun Zhang Lin liu Heng-zhi fu State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi＇an 710072 China

Oxide eutectic ceramic in situ composites have attracted significant interest in the application of high-temperature structural materials because of their excellent high-temperature strength,oxidation and creep resistance,as well as outstanding microstructural *** directionally solidified ternary Al2O3/YAG/ZrO2 hypereutectic in situ composite was successfully prepared by a laser zone remelting method,aiming to investigate the growth characteristic under ultra-high temperature *** microstructures and phase composition of the as-solidified hypereutectic were characterized by using scanning electron microscopy（SEM）,energy dispersive spectroscopy（EDS）,and X-ray diffraction（XRD）.The results show that the composite presents a typical hypereutectic lamellar microstructure consisting of fine Al2O3 and YAG phases,and the enriched ZrO2 phases with smaller sizes are randomly distributed at the Al2O3/YAG interface and in Al2O3 *** power and scanning rate strongly affect the sample quality and microstructure ***,coarse colony microstructures were also observed,and their formation and the effect of temperature gradient on the microstructure were discussed.

关键词： eutectics ceramic materials microstructure thermal gradients remelting solidification

Molecularly Imprinted Polymers on Chloromethyl Polystyrene Resin Prepared via RAFT Polymerization

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Chinese Chemical Letters 2006年第4期17卷 549-552页

作者： Zhen Xia DU Hong liu zhi Feng fu Wan Tai YANG Key Laboratory for Controlled Chemical Reactions of Education Ministry Beijing University of Chemical Technology Beijing 100029

Surface molecularly imprinted polymers （SMIP） was prepared via the reversible addition-fragmentation chain transfer （RAFT） polymerization on the chloromethyl polystyrene resin （CPR） in the presence of the template D-phenylalanine. The structure of SMIP was characterized by FTIR and SEM. The adsorption behavior of D-phenylalanine of SMIP was preliminarily investigated.

关键词： Surface molecularly imprinted polymers reversible addition-fragmentation chain transfer.

Research progress on micro-force measurement of a hydrate particle system

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Petroleum Science 2024年第4期21卷 2169-2183页

作者： Qiang Luo Wei Li zhi-Hui liu Feng Wang zhi-Chao liu fu-Long Ning Faculty of Engineering China University of Geosciences (Wuhan) Suzhou Laboratory

It remains a great challenge to understand the hydrates involved in phenomena in practical oil and gas systems. The adhesion forces between hydrate particles, between hydrate particles and pipe walls, and between hydrate particles and reservoir particles are essential factors that control the behaviors of clathrate hydrates in different applications. In this review, we summarize the typical micro-force measurement apparatus and methods utilized to study hydrate particle systems. In addition, the adhesion test results, the related understandings, and the applied numerical calculation models are systematically discussed.

关键词： Clathrate hydrates Hydrate particle Micro-force measurements Adhesion Interactions

Incorporating Lasso Regression to Physics-Informed Neural Network for Inverse PDE Problem

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 385-399页

作者： Meng Ma liu fu Xu Guo zhi Zhai National Key Lab of Aerospace Power System and Plasma Technology Xi’an Jiaotong UniversityXi’an710049China School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an710049China Department of Electrical and Computer Engineering University of Massachusetts LowellLowellMA 01854USA

Partial Differential Equation(PDE)is among the most fundamental tools employed to model dynamic *** PDE modeling methods are typically derived from established knowledge and known phenomena,which are time-consuming and ***,discovering governing PDEs from collected actual data via Physics Informed Neural Networks(PINNs)provides a more efficient way to analyze fresh dynamic systems and establish *** study proposes Sequentially Threshold Least Squares-Lasso(STLasso),a module constructed by incorporating Lasso regression into the Sequentially Threshold Least Squares(STLS)algorithm,which can complete sparse regression of PDE coefficients with the constraints of l0 *** further introduces PINN-STLasso,a physics informed neural network combined with Lasso sparse regression,able to find underlying PDEs from data with reduced data requirements and better *** addition,this research conducts experiments on canonical inverse PDE problems and compares the results to several recent *** results demonstrated that the proposed PINN-STLasso outperforms other methods,achieving lower error rates even with less data.

关键词： Physics-informed neural network inverse partial differential equation Lasso regression scientific machine learning

Atmospheric Deposition-Carried Pb, Zn, and Cd from a Zinc Smelter and Their Effect on Soil Microorganisms

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Pedosphere 2009年第4期19卷 422-433页

作者： YANG Yuan-Gen2, JIN zhi-Sheng, BI Xiang-Yang, LI Fei-Li, SUN Li, liu Jie and fu zhi-You Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002 (China) Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 (China)

Dust emissions from smelters, as a major contributor to heavy metal contamination in soils, could severely influence soil quality. Downwind surface soils within 1.5 km of a zinc smelter, which was active for 10 years but ceased in 2000, in Magu Town, Cuizhou Province, China were selected to examine Pb, Zn, and Cd concentrations and their fractionation along a distance gradient from a zinc smelter, and to study the possible effects of Pb, Zn, and Cd accumulation on soil microorganisms by comparing with a reference soil located at a downwind distance of 10 km from the zinc smelter. Soils within 1.5 km of the zinc smelter accumulated high levels of heavy metals Zn （508 mg kg^-1）, Pb （95.6 mg kg^-1）, and Cd （5.98 mg kg^-1） with low ratios of Zn/Cd （59.1-115） and Pb/Cd （12.4-23.4）. Composite pollution indices （CPIs） of surface soils （2.52-15.2） were 3 to 13 times higher than the reference soils. In metal accumulated soils, exchangeable plus carbonate-bound fractions accounted for more than 10% of the total Zn, Pb, and Cd. The saturation degree of metals （SDM） in soils within 1.5 km of the smelter （averaging 1.25） was six times higher than that of the reference soils （0.209）. A smaller soil microbial biomass was found more frequently in metal accumulated soils （85.1-438 μg C g^-1） than in reference soils （497 μg C g^-1）, and a negative correlation （P 〈 0.01） of soil microbial biomass carbon to organic carbon ratio （Cmic/Corg） with SDM was observed. Microbial consumption of carbon sources was more rapid in contaminated soils than in reference soils, and a shift in the substrate utilization pattern was apparent and was negatively correlated with SDM （R = -0.773, P 〈 0.01）. Consequently, dust deposited Pb, Zn, and Cd in soils from zinc smelting were readily mobilized, and were detrimental to soil quality mainly in respect of microbial biomass .

关键词： composite pollution index heavy metals microbial biomass saturation degree of metals sequential extrac- tion

Relationship between seismic structures and the diverse rupture processes of the 2023 Türkiye earthquake doublet

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Science China Earth Sciences 2024年第9期67卷 2810-2823页

作者： zhi WANG Yi fu Shunping PEI CAS Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Recent geodetic and seismological observations of two major earthquakes in southeastern Türkiye in February 2023 have revealed complex rupture initiation,propagation,and segmentation along the East Anatolian Fault Zone(EAFZ)and surrounding ***,the role of upper crust structures along the EAFZ in determining the diverse rupture processes of this earthquake doublet remains *** further investigate this,we employed double-difference location and seismic tomography techniques to determine high-resolution seismic velocities(V_(P),V_(S))and Poisson’s ratio(σ)structures using a multiparameter joint tomographic *** dataset includes 100,833 high-quality source-receiver travel-time pairs of P-and *** find that the unique rupture processes of this earthquake doublet were primarily influenced by contrasting crustal seismic structures and localized geological *** M_(w)7.8 mainshock was initiated within a transitional edge zone characterized by a rigid part(asperity)of the seismogenic zone with sharp contrast variations in rock strength ranging from low to high along the *** comparison,the M_(w)7.6 rupture originated in a ductile belt featuring fluid saturation with low-VP,low-VS,and high-σvalues that extended parallel to the Cardak *** pronounced contrast structures observed along the former rupture can be attributed to the oblique collision system between the weakened section of the east Anatolian plateau and the brittle Arabian platform,while the latter rupture was initiated within the ductile structure associated with fluid intrusion caused by the northward subduction of the Cyprus slab and subsequent ***,the occurrence of the first earthquake(E1)serves to alleviate shear stress on the second earthquake(E2)fault,potentially impeding the initiation of an E2 *** the contrary,this event also significantly reduces the normal stress acting on the E2 fault due to a double left-lateral strike-slip system

关键词： 2023 Turkiye earthquake doublet Joint seismic tomography Tomographic transition edge Seismic rupture process Strong fault coupling

Waveguide electro-optic modulators based on self-assembled material systems

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光学精密工程 2005年第5期13卷 554-560页

作者： liu zhi-fu MA Jing SUN De-gui XU Guo-yang HO Seng-Tiong ZHU Pei wang KANG Hu Antonio Facchetti Tobin J. Marks Department of Electrical and Computer Engineering Northwestern University Evanston IL 60208 USA Department of Chemistry and Materials Research Center Northwestern University Evanston IL 60208 USA

Fabrication and characterization of electro-optic modulators based on the novel organic electro-optic materials composed of self-assembled superlattices (SAS) were presented, both wet-dipping self-assembly and vapor phase deposition approaches were discussed. Prototype waveguide electro-optic modulators were fabricated using SAS films integrated with low-loss polymeric materials functioning as partial guiding and cladding *** electro-optic thin film materials including DTPT and PEPCOOH grown from the vapor phase were used for fabrication and test of electro-optic prototype modulators. Finally,the EO coefficient of tens of pm/V was obtained,which can sufficiently support high-speed and small size EO modulators.

关键词：电子波导光电子调节器 SAS 薄膜

Polydatin ameliorates hepatic ischemia-reperfusion injury by modulating macrophage polarization

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 25-34页

作者： Hai-Li Bao Chuan-zhi Chen Chang-Zhen Ren Ke-Yan Sun Hao liu Shao-Hua Song zhi-Ren fu Department of Organ Transplantation Shanghai Changzheng HospitalNavy Military Medical UniversityShanghai 200003China Department of Surgical Oncology the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Department of Cardiology Shanghai Changzheng HospitalNaval Military Medical UniversityShanghai 200003China Department of General Surgery Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China

Background:Polydatin,a glucoside of resveratrol,has shown protective effects against various ***,little is known about its effect on hepatic ischemia-reperfusion(I/R)*** study aimed to elucidate whether polydatin protects liver against I/R-induced injury and to explore the underlying ***:After gavage feeding polydatin once daily for a week,mice underwent a partial hepatic I/R *** alanine aminotransferase(ALT)/aspartate aminotransferase(AST),hematoxylin-eosin(H&E)and TdT-mediated dUTP nick-end labeling(TUNEL)staining were used to evaluate liver *** severity related to the inflammatory response and reactive oxygen species(ROS)production was also ***,immunofluorescence and Western blotting were used to detect macrophage polarization and the NF-κB signaling pathway in ***:Compared with the I/R group,polydatin pretreatment significantly attenuated I/R-induced liver damage and *** oxidative stress marker(dihydroethidium fluorescence,malondialdehyde,superoxide dismutase and glutathione peroxidase)and I/R related inflammatory cytokines(interleukin1β,interleukin-10 and tumor necrosis factor-α)were significantly suppressed after polydatin *** addition,the result of immunofluorescence indicated that polydatin reduced the polarization of macrophages toward M1 macrophages both in vivo and in *** blotting showed that polydatin inhibited the pro-inflammatory function of RAW264.7 via down-regulating the NF-κB signaling ***:Polydatin protects the liver from I/R injury by remodeling macrophage polarization via NFκB signaling.

关键词： Hepatic ischemia-reperfusion injury Polydatin Macrophage Polarization Inflammation

A dual measurement method of strain and temperature

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Journal of Marine Science and Application 2007年第1期6卷 63-68页

作者： JIANG Hai-li SUN Wei-min ZHANG Cong liu zhi-hai JIANG fu-qiang ZHANG Yang College of Science Harbin Engineering University Harbin 150001 China

With the rapid development of China's foreign trade, the coastal and inland waterway transport has been increased rapidly. The potential market for marine engines is more and more obvious. The measurement of the engine temperature and strain becomes very important. The fluorescence fiber sensors are broadly used to measure temperature, concentration, and pH value, etc. The fluorescence sensing systems are based on different principles, namely fluorescence intensity, fluorescence intensity ratio, and fluorescence lifetime. The fluorescence lifetime is an effective parameter for sensing purpose, because it is independent of the intensity of the pumping source and does not need expensive narrow-band filters. An experiment system has been established, in which some samples were produced to measure the fluorescence lifetime and temperature characteristics and the relationship of the strain and temperature versus the fluorescence lifetime was achieved at the same time. The experiment result was fitted and analyzed. The test results show that the fluorescence lifetime decreases with the increasing of temperature. The change of fluorescence lifetime with the strain is inconspicuous comparing to that with the temperature.

关键词： fluorescence lifetime fluorescence fiber simultaneous measurement temperature strain