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Effects of Dendritic Orientation on Stress Rupture Properties of DD6 Single Crystal Superalloy

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Journal of Iron and Steel Research International 2011年第10期18卷 66-71页

作者： shi Zhen-xue li Jia-rong liU shi-zhong ZHAOJin-qian National Key Laboratory of Science and Technology on Advanced High Temperature Structural Materials Beijing Institute of Aeronautical Materials Beijing 100095 China

DD6 single crystal superalloy slabs were prepared with seed method in the direetionally solidified furnace with high temperature gradient. The transverse stress rupture properties and fracture hehaviour of the alloy at 760 ℃/758 MPa, 850 ℃/550 MPa and 980 ℃/250 MPa were investigated and compared with those of longitudinal specimens. The transverse stress rupture lives are corresponding with the longitudinal stress rupture lives at 760 ℃/758 MPa and 850 ℃/550 MPa. The transverse stress rupture lives are slightly less than the longitudinal stress rupture lives at 980 ℃/ 250 MPa. The fracture mechanism of the transverse stress rupture of the alloy at 760 ℃/758 MPa shows quasi-cleav- age mode and the fracture mechanism at 980 ℃/250 MPa shows dimple mode, while the fracture mechanism at 850 ℃/ 550 MPa shows quasi-cleavage and dimple mixture mode. At higher temperature and lower stress, the microeracks are easier to initiate and interconnect in the transverse specimen than those in longitudinal specimen because there are interdendritic regions perpendicular to the axis of stress.

关键词： DD6 single crystal superalloy stress rupture property fracture behaviour

The sensitivity of digestive tract tumor cells to As_2O_3 is associated with the inherent cellular level of reactive oxygen species

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World Journal of Gastroenterology 2002年第1期8卷 36-39页

作者： Fei Gao Jing Yi Gui-Ying shi Hui li xue-Geng shi xue-Ming Tang Department of Cell Biology,Shanghai Second Medical University,Shanghai 200025,China Department of Cell Biology Shanghai Second Medical University Shanghai 200025 China.

AIM:To explore the correlation of the inherent cellular ROSlevel with the susceptibility of the digestive tract tumor cellsto apoptosis inducted by As_2O_***:Two gastric cercinoma cell lines,SGC7901 andMKN45,and two esophageal carcinoma cell lines,EC/CUHKI(alternatively named EC1.71)and EC1867 with lowconcentration(2μmol·L^(-1))of As_2O_3 were cultured respectly,which confirmed the difference in apoptosis susceptibilitybetween SGC7901 and MKN45,and between EC/CUHK1 *** cells were incubated withdihydrogenrhodamine123(DHR123),used as a ROScapture,in absence of As_2O_*** fluorescent intensity ofrhodamine123,which was the product of cellular oxidationof DHR123,was detected by flow cytometry,and ROS ***:Apoptosis induced by a low concentration ofAs203 was more readily to occur in SGC7901(22.4%±2.4%)and EC/CUHK1(27.0%±2.9%)than in MKN45(2.1%±0.5%)and EC1867(0.8%±0.5%).In other words,SGC7901was more sensitive than MKN45 to As_2O_3,meanwhile EC/CUHK1 was more sensitive than EC1867 to As_2O_*** levelof inherent cellular ROS in SGC7901(650±37)was higherthan that in MKN45(507±22)(P<0.01),and the level ofinherent cellular ROS in EC/CUHK1(462±17)was higherthan that in EC1867(187±12)(P<0.01).*** cellular sensitivity to apoptosis inducedby As_2O_3 is associated with the difference in cellular *** inherent ROS level might determinate theapoptotic sensitivity of tumor cells to As_2O_3.

关键词：肿瘤治疗学细胞内ROS 消化道肿瘤细胞凋亡 As2O3 敏感性

Efects of Cropland Cover Changes on Regional Climate over Western China Based on Simulations with RegCM3

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Advances in Climate Change Research 2013年第4期4卷 250-259页

作者： shi xue-li HE Hui-Juan REN Hong-Chang National Climate Center China Meteorological Administration Shaanxi Remote Sensing Information Center for Agriculture Nanjing University of Information Science and Technology

The impacts of land cover changes on regional climate with RegCM3. Sensitivity experiments were conducted by in Shaan-Gan-Ning （SGN） in western China were simulated replacing crop grids with different new land cover types in the key area of SGN, where the returning cropland to tree/grass project has been carried out since 1999. The modified new land cover types include desert, forest, shrub and grass. They represent degraded, improved, and maintained vegetation cover with natural canopy in the key area. Results from three individual case studies show that the land cover change causes changes in temperature and terrestrial water variables especially within the key area, while changes in precipitation are found for a larger area. The strongest changes appear where the cropland is degraded to bare soil, leading to increasing temperature and decreases in rainfall, evaporation and soil water. Opposite changes occur when cropland changed into forests, especially with strong increases in soil water. When cropland changed to grass and shrub land, the climatic changes are closer to those with forest cover. This shows the importance of improving and maintaining the vegetation in SGN for the ecosystem and regional climate.

关键词： land cover change RegCM3 regional climate

Quality Control and Analysis of Global Gauge-Based Daily Precipitation Dataset from 1980 to 2009

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Advances in Climate Change Research 2012年第1期3卷 45-53页

作者： NIE Su-Ping LUO Yong li Wei-Ping WU Tong-Wen shi xue-li WANG Zai-Zhi Laboratory for Climate Studies National Climate CenterChina Meteorological AdministrationBeijing 100081China

A series of quality control(QC) procedures were performed on a gauge-based global daily precipitation dataset from the Global Telecommunication System(GTS) for the period 1980-2009.A new global daily precipitation(NGDP) dataset was constructed by applying those QC procedures to eliminate erroneous *** NGDP dataset was evaluated using the NOAA Climate Prediction Center Merged Analysis of Precipitation(CMAP) and the Global Precipitation Climatology Project(GPCP) precipitation *** results showed that the frequency distribution and spatial distribution pattern of NGDP had a nice match with those from the CMAP and GPCP *** global mean correlation coefficients with the CMAP and GPCP data increased from 0.24 for original GTS precipitation data to about 0.70 for NGDP ***,the root mean square errors(RMSE) decreased from 12 mm per day to 1 mm per *** interannual variabilities of NGDP monthly precipitation are consistent with the CMAP and GPCP datasets in ***,the seasonal variabilities for most land areas on the Earth of NGDP dataset are also consistent with the CMAP and GPCP precipitation products.

关键词： global surface weather report data GTS data daily precipitation quality control

Bright single-photon sources in the telecom band by deterministically coupling single quantum dots to a hybrid circular Bragg resonator

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Photonics Research 2022年第8期10卷 I0001-I0006页

作者： shi-WEN XU YU-MING WEI RONG-BIN SU xue-shi li PEI-NIAN HUANG SHUN-FA liU XIAO-YING HUANG YING YU JIN liU xue-HUA WANG State Key Laboratory of Optoelectronic Materials and Technologies School of PhysicsSchool of Electronics and Information TechnologySun Yat-sen UniversityGuangzhou 510275China

High-performance solid-state quantum sources in the telecom band are of paramount importance for longdistance quantum communications and the quantum Internet by taking advantage of a low-loss optical fiber ***,we demonstrate bright telecom-wavelength single-photon sources based on In(Ga)As/Ga As quantum dots(QDs)deterministically coupled to hybrid circular Bragg resonators(h-CBRs)by using a wide-field fluorescence imaging *** QD emissions are redshifted toward the telecom O-band by using an ultra-low In As growth rate and an In Ga As strain reducing ***-photon emissions under both continuous wave(CW)and pulsed operations are demonstrated,showing high brightness with count rates of 1.14 MHz and 0.34 MHz under saturation powers and single-photon purities of g^(2)(0)=0.11±0.02(CW)and g^(2)(0)=0.087±0.003(pulsed)at low excitation powers.A Purcell factor of 4.2 with a collection efficiency of 11.2%±1%at the first lens is extracted,suggesting efficient coupling between the QD and *** work contributes to the development of highly efficient single-photon sources in the telecom band for fiber-based quantum communication and future distributed quantum networks.

关键词： quantum circular coupling

Global climate damage in 2℃ and 1.5℃ scenarios based on BCC_SESM model in IAM framework

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Advances in Climate Change Research 2020年第3期11卷 261-272页

作者： ZHAO Zi-Jian CHEN Xiao-Tong liU Chang-Yi YANG Fang TAN Xin ZHAO Yang HUANG Han WEI Chao shi xue-li ZHAI Wen GUO Fei Bas J.VAN RUIJVEN Global Energy Interconnection Development and Cooperation Organization Beijing100031China National Climate Center China Meteorological AdministrationBeijing100081China Beijing City University Beijing100083China International Institute for Applied Systems Analysis(II ASA) Laxenburg2361Austria

The quantitative functions for climate damages provide theoretical ground for the cost-benefit analysis in climate change economics,and they are also critical for linking climate module with economic module in the Integrated Assessment Models(IAMs).Nevertheless,it is necessary for IAMs to update sectoral climate impacts in order to catch up the advance in climate change *** study updates the sectoral climate damage function at global scale from climate Framework for Uncertainty,Negotiation and Distribution(FUND)model and develops the aggregate climate damage function in a bottom-up *** conventional sectors such as agriculture,forestry,water resources,energy consumption and ecosystems,this study expands climate disaster types,assesses human health impacts caused by various air pollutants,and updates coastal damage by sea level *** Beijing Climate Center Simple Earth System Model(BCC_SESM)is used to project climate system based on Business-as-Usual(BAU)scenario,and the 2℃ and 1.5℃ scenarios based on RCPs and SSP2 *** results show that the agricultural sector is projected to suffer 63% of the total damage,followed by water resources(16%)and human health(12%)sectors in *** regression results indicate that the aggregate climate damage function is in positive quadratic form for zero *** BAU scenario,the aggregate climate damage is projected to be 517.7 trillion USD during *** to that,the 2℃ and 1.5℃ scenarios are projected to respectively reduce climate damages by 215.6 trillion USD(approximately 41.6%)and 263.5 trillion USD(50.9%)in 2011-2100.

关键词： Climate change Climate impact Climate damage function Integrated assessment model(IAM) Earth system model(ESM)

Boosting hydrocarbon conversion via Cu-doping induced oxygen vacancies on CeO2 in CO2 electroreduction

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Journal of Energy Chemistry 2025年第1期100卷 66-76页

作者： Lei xue Tong shi Chenhui Han Heng Zhang Fenrong liu Haorun li Yan Wang Xiaojun Gu Shanghong Zeng Inner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials School of Chemistry and Chemical Engineering Inner Mongolia University State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Institute of Catalysis Department of Chemistry Zhejiang University National Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization Baotou Research Institute of Rare Earths

Conversion of CO2back to hydrocarbons is the most direct way of closing the“carbon cycle”,and its significance is further enlarged if this process is driven by renewable energies such as ***,precisely controlling the product selectivity towards hydrocarbons against the competitive hydrogen evolution remains challenging,especially for Cu-based ***,we report a novel defect engineering strategy,by which Cu-doping-induced oxygen vacancies on CeO2nanorods were effectively created,with adjustable vacancy/Cu *** resulting optimum catalyst shows up to 79% catalytic current density to hydrocarbons （excluding CO）,with 49% faradaic efficiency to *** and density functional theory unveil that the ratio between oxygen vacancy and Cu affects significantly the formation of*CHO and activation of H2O,which leads to the following deep hydrogenation to *** findings may spur new insights for designing and developing more controllable chemical process relevant to CO2utilization.

关键词： Nanorods

Dicoumarol Alters Cellular Redox State and Inhibits Nuclear Factor Kappa B to Enhance Arsenic Trioxide-Induced Apoptosis

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Acta Biochimica et Biophysica Sinica 2004年第3期36卷 235-242页

作者： Ya-Wu JING, Jing YI, Yu-Ying CHEN, Qing-Shen HU, Gui-Ying shi, Hue li, and xue-Ming TANG* Department of Cell Biology, Shanghai Second Medical University, Shanghai 200025, China Department of Cell Biology Shanghai Second Medical University Shanghai 200025 China

The effects of a number of cytotoxic drugs are influenced by cellular reduction/oxidation (redox) state. In the present study, we attempt to explore if dicoumarol, an inhibitor of NADPH: quinone oxidoreductase (NQO1), alters the cellular redox state and how this alteration affects the redox-related apoptosis. Flow cytometry was used to assess the reactive oxygen species (ROS) level and apoptotic rates of HeLa cells treated with arsenic trioxide (As2O3) alone or in combination with natural anthraquinone emodin and dicoumarol or plus N-acetyl-cysteine. Western blot, immunofluorescence, electrophoretic mobility shift assay and luciferase assay were used to detect Nuclear Factor kappa B (NF-κB) activation. The results showed that dicoumarol synergized with emodin to sensitize HeLa cells to As2O3-induced apoptosis through raising the ROS level. More notably, this enhanced susceptibility was associated with a ROS-mediated inhi- bition of NF-κB activation in which the combinative treatment with dicoumarol prevented NF-κB from binding to target DNA. It was suggested that dicoumarol in combination with anthraquinones might be a novel strategy to expand the chemotherapeutic spectrum of As2O3 by means of interfering the cellular redox state.

关键词： dicoumarol arsenic trioxide reduction/ oxidation state apoptosis NF-κB

Joint Feature Encoding and Task Alignment Mechanism for Emotion-Cause Pair Extraction

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Computers, Materials & Continua 2025年第1期82卷 1069-1086页

作者： shi li Didi Sun College of Computer and Control Engineering Northeast Forestry UniversityHarbin150040China

With the rapid expansion of social media,analyzing emotions and their causes in texts has gained significant ***-cause pair extraction enables the identification of causal relationships between emotions and their triggers within a text,facilitating a deeper understanding of expressed sentiments and their underlying *** comprehension is crucial for making informed strategic decisions in various business and societal ***,recent research approaches employing multi-task learning frameworks for modeling often face challenges such as the inability to simultaneouslymodel extracted features and their interactions,or inconsistencies in label prediction between emotion-cause pair extraction and independent assistant tasks like emotion and cause *** address these issues,this study proposes an emotion-cause pair extraction methodology that incorporates joint feature encoding and task alignment *** model consists of two primary components:First,joint feature encoding simultaneously generates features for emotion-cause pairs and clauses,enhancing feature interactions between emotion clauses,cause clauses,and emotion-cause ***,the task alignment technique is applied to reduce the labeling distance between emotion-cause pair extraction and the two assistant tasks,capturing deep semantic information interactions among *** proposed method is evaluated on a Chinese benchmark corpus using 10-fold cross-validation,assessing key performance metrics such as precision,recall,and F1 *** results demonstrate that the model achieves an F1 score of 76.05%,surpassing the state-of-the-art by 1.03%.The proposed model exhibits significant improvements in emotion-cause pair extraction(ECPE)and cause extraction(CE)compared to existing methods,validating its *** research introduces a novel approach based on joint feature encoding and task alignment mechanisms,contributing to advancements in emotion-c

关键词： Emotion-cause pair extraction interactive information enhancement joint feature encoding label consistency task alignment mechanisms