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Journal of Magnesium and Alloys 2024年第1期12卷 251-266页

作者： fei-er Shangguan Wei-li Cheng Yu-hang Chen Ze-qin Cui Hui Yu Hong-xia wang li-fei wang Hang li Hua Hou School of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China School of Materials Science and Engineering Hebei University of TechnologyTianjin 300132China School of Materials Science and Engineering North University of ChinaTaiyuan 030051China

The influence of micro-Ca/In alloying on the microstructural charac teristics,electrochemical behaviors and discharge properties of extruded dilute Mg-0.5Bi-0.5Sn-based(wt.%)alloys as anodes for Mg-air batteries are *** grain size and texture intensity of the Mg-Bi-Sn-based alloys are significantly decreased after the Ca/In alloying,particularly for the In-containing *** that,in addition to nanoscale Mg_(3)Bi_(2)phase,a new microscale Mg_(2)Bi_(2)Ca phase forms in the Ca-containing *** electrochemical test results demonstrate that Ca/In micro-alloying can enhance the electrochemical *** In to alloy the Mg-Bi-Sn-based alloy is effective in restricting the cathodic hydrogen evolution(CHE)kinetics,leading to a low self-corrosion rate,while severe CHE occurred after Ca *** micro-alloying of Ca/In to Mg-Bi-Sn-based alloy strongly deteriorates the compactness of discharge products film and mitigates the"chunk effect"(CE),hence the cell voltage,anodic efficiency as well as discharge capacity are greatly *** In-containing alloy exhibits outstanding discharge performance under the combined effect of the modified microstructure and discharge products,thus making it a potential anode material for primary Mg-air battery.

关键词： Mg-air batteries Mg-Bi-Sn based alloys Electrochemical behaviors Discharge properties

Diastereoselective addition of lithium enolate of γ-substituted α-diazoacetoacetate to N-sulfinyl imines

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Chinese Science Bulletin 2010年第25期55卷 2847-2854页

作者： MO FanYang li fei wang JianBo Beijing National Laboratory of Molecular Sciences (BNLMS) and Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Minis- try of Education College of Chemistry Peking University Beijing 100871 China

Highly diastereoselective addition of lithium enolate of γ-substituted α-diazoacetoacetate to chiral N-sulfinyl imines has been developed. The addition products were further subjected to photo-induced Wolff rearrangement or Rh(Ⅱ)-catalyzed intramolecular N-H insertion to afford chiral 4,5-disubstituted 2-oxo and 3-oxo pyrrolidines,respectively.

关键词：烯醇酰亚胺 Wolff重排锂二羰基二取代手性催化

Multimodal imaging study of lipemia retinalis with diabetic retinopathy:A case report

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World Journal of Clinical Cases 2022年第19期10卷 6736-6743页

作者： Sheng-Juan Zhang Zhong-Yang Yan li-fei Yuan Yan-Hui wang li-fei wang Department of Ophthalmology Hebei Provincial Eye HospitalHebei Provincial Key Laboratory of OphthalmologyHebei Provincial Eye InstituteXingtai 054001Hebei ProvinceChina

BACKGROUND lipemia retinalis(LR)is a rare disease related to ***,the symptoms of hypertriglyceridemia are insidious and difficult to detect without blood *** fundus is the only site where blood vessels can be observed *** the specific performance of LR in multimodal imaging fundus examinations can help diagnose more patients with abnormal *** SUMMARY A 29-year-old woman with type 2 diabetes presented to our clinic complaining of a six-day loss of visual acuity in the left *** fundus color images showed typical LR:Arteries and veins were the same pink-white *** images showed hyperinfrared reflections of the arteries and *** coherence tomography(OCT)showed numerous high point-like reflections in the retinal section,corresponding to different calibers of blood vessel *** reflections were seen in the big vessels of the *** fluorescein angiography(FFA)and optical coherence tomography angiography(OCTA)showed no significant *** examination found a total cholesterol level of 13.98 mmol/L,triglyceride 20.55 mmol/L,which confirmed the diagnosis of *** treatment to lower blood lipids and control blood glucose,the fundus imaging showed that the blood lipids in the patient had returned to *** LR shows specific changes in fundus color photography,infrared photography,and *** and OCTA were not sensitive to LR changes.

关键词： lipemia retinalis Fundus color photography Infrared photography Optical coherence tomography Fundus fluorescein angiography Case report

Unveiling the twinning and dynamic recrystallization behavior and the resultant texture evolution in the extruded Mg-Bi binary alloys during hot compression

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Journal of Materials Science & Technology 2022年第10期105卷 274-285页

作者： Yu-qin Zhang Wei-li Cheng Hui Yu Hong-xia wang Xiao-feng Niu li-fei wang Hang li School of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of Education Taiyuan University of TechnologyTaiyuan 030024China School of Materials Science and Engineering Hebei University of TechnologyTianjin 300132China

The twinning behavior, dynamic recrystallization(DRX) mechanism and the resultant texture evolution of the extruded Mg-xBi(x=0.5 wt.%, 2.0 wt.%) alloys were systematically investigated during hot compression at the strain rate of 10 s^(-1) and temperature of 200℃. The results indicate that the types and intensities of the texture are greatly dependent on the twining behavior and DRX mechanism. At the initial stage, the evolution of texture is mainly domination by the formation and variation of {1012} extension twins, which is benefcial to the compression direction(CD)-tilted basal texture. With an increase in the strain, the texture evolution is more greatly regulated by the DRX mechanism. Besides, the pyramidal slip and basal slip are activated during the compression process, resulting in the Schmid factors(SF) of pyramidal slip remain at ~0.4 and the average SFs for basal slip increase from 0.2 to0.34 as the strain increase. These fndings provide a new insight into controlling the texture of wrought Mg-Bi-based alloys during hot deformation processing.

关键词： Wrought Mg-Bi alloys Hot deformation Twinning Dynamic recrystallization Dislocation slip Texture

Modification of MgO·Al_2O_3 spinel inclusions in Al-killed steel by Ca-treatment

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International Journal of Minerals,Metallurgy and Materials 2011年第1期18卷 18-23页

作者： Shu-feng Yang Jing-she li Zai-fei wang Jiao li lin lin School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

The modification of MgO·Al2O3 spinel inclusions in Al-killed steel by Ca-treatment has been studied by industrial trials and thermodynamic *** the industrial trials,samples were taken systematically during the refining process in which the molten steel was treated by calcium,and the characters of the inclusions were analyzed using scanning electron microscopy （SEM） and energy dispersive spectra （EDS）.The effects of Ca-treatment were evaluated by tracking the compositions of the *** results show that the modification of MgO·Al2O3 spinel inclusions by Ca-treatment is effective and the transformation sequence of the inclusions during the refining is Al2O3 →MgO·Al2O3 →liquid complex *** modification of spinel inclusions by Ca-treatment was calculated by FactSage 6.0 utilizing its free-energy minimization *** results of thermodynamic calculations indicate that spinel inclusions are easier to be modified than Al2O3 inclusions and the spinel inclusions in 30CrMo steel would transform to liquid complex inclusions when the content of dissolved Ca in the molten steel exceeds 1×***,the results show that adding more calcium into the molten steel would lower the contents of Al2O3 and MgO and increase the CaO content of the inclusions,while the change in SiO2 content is little.

关键词： steel metallurgy inclusions magnesia alumina chemical modification thermodynamics

Plants of Leptostrobus Heer （Czekanowskiales） from the Early Cretaceous and Late Triassic of China, with Discussion of the Genus

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Journal of Integrative Plant Biology 2006年第2期48卷 137-147页

作者： Xiu-Qun liu Cheng-Sen li Yu-fei wang Laboratory of Systematic and Evolutionary Botany Institute of Botany the Chinese Academy of Sciences Beijing 100093 China

Investigation of the Mesozoic seed plant Leptostrobus Heer from the Yangcaogou Formation of the Late Triassic and the Yixian Formation of the Early Cretaceous, liaoning Province, China, provides new Insight Into Its general morphology and geographical distribution. The materials of L. cancer from the Yixian Formation described herein are later than all the past findings of this species and add to the record of L. cancer during the Early Cretaceous. Based on well-preserved specimens, the specific diagnosis Is slightly emended and the reconstructlon of L. cancer Is perfected. The materials from the Yangcaogou Formation of the Late Triassic are placed in L. spheericus, in addition, we review the history of investigation of the genus Leptostrobus since its establishment in 1876 and discuss the main characteristics of each species.

关键词： Early Cretaceous Late Triassic Leptostrobus Yangcaogou Formation Yixian Formation.

Development and assessment of quantitative structure-activity relationship models for bioconcentration factors of organic pollutants

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Chinese Science Bulletin 2009年第4期54卷 628-634页

作者： QIN Hong CHEN JingWen wang Ying wang Bin li XueHua li fei wang YaNan Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education) Department of Environmental Scienceand Technology Dalian University of Technology Dalian 116024 China

Bioconcentration factors (BCFs) are of great importance for ecological risk assessment of organic chemicals. In this study, a quantitative structure-activity relationship (QSAR) model for fish BCFs of 8 groups of compounds was developed employing partial least squares (PLS) regression, based on linear solvation energy relationship (LSER) theory and theoretical molecular structural descriptors. The guidelines for development and validation of QSAR models proposed by the Organization for Economic Cooperation and Development (OECD) were followed. The model results show that the main factors governing logBCF are Connolly molecular area (CMA), average molecular polarizability (α) and molecular weight (MW). Thus molecular size plays a critical role in affecting the bioconcentration of organic pollutants in fish. For the established model, the multiple correlation coefficient square (RY2) = 0.868, the root mean square error (RMSE) = 0.553 log units, and the leave-many-out cross-validated Q2CUM = 0.860, indicating its good goodness-of-fit and robustness. The model predictivity was evaluated by external validation, with the external explained variance (QE2XT) = 0.755 and RMSE = 0.647 log units. Moreover, the applicability domain of the developed model was assessed and visualized by the Williams plot. The developed QSAR model can be used to predict fish logBCF for organic chemicals within the application domain.

关键词：生物浓缩因子定量结构活动关系有机污染物生态学风险评估

Methane emissions from terrestrial plants over China and their effects on methane concentrations in lower troposphere

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Chinese Science Bulletin 2009年第2期54卷 304-310页

作者： XIE Min li Shu JIANG fei wang TiJian Department of Atmospheric Sciences Nanjing University Nanjing 210093 China

Methane (CH4) is the most important greenhouse gas and reactive trace gas in the atmosphere. Recently, it has been reported that terrestrial plants can emit CH4 under aerobic conditions, which may call for reevaluation of the inventory of CH4 emissions in China. In this paper, those emissions over China and their effects on CH4 concentrations in lower troposphere were investigated. Firstly, based on the work of Keppler et al., the aerobic plant CH4 emission model (PLANTCH4) for China was established. And by using the database of normalized difference vegetation index (NDVI) derived from NOAA/ AVHRR, the distribution of net primary productivity (NPP) over China was simulated, and thereby, for the first time, the amount and distribution of the newly identified source in China were estimated. Secondly, with the aid of the three-dimensional atmospheric chemistry model system (MM5-CALGRID), the effects of the emissions were studied. The results show that the annual aerobic plant CH4 emissions over China amount to 11.83 Tg, i.e. nearly 24% of Chinese total CH4 emissions. And the major fraction (about 43%) comes from forests. When those emissions are considered in modeling, computed countrywide mean surface concentration of CH4 is 29.9% higher than without them, with a maximum increase of 69.61 μg·m-3 in the south of Yunnan Province. In conclusion, to study CH4 emissions from terrestrial plants over China may have important implications for correctly estimating the contribution of China to global CH4 budget, and may call for a reconsideration of the role of CH4 in global and regional environment and climate change.

关键词：环境污染大气污染甲烷治理技术

Tailoring the microstructural characteristics and enhancing creep properties of as-cast Mg-5Bi-5Sn alloy through Mn addition

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Journal of Magnesium and Alloys 2023年第9期11卷 3350-3361页

作者： Yi-hao Luo Wei-li Cheng Hui Yu Hong-xia wang Xiao-feng Niu li-fei wang Hang li Zhi-yong You Hua Hou School of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of Education Taiyuan University of TechnologyTaiyuan 030024China School of Materials Science and Engineering Hebei University of TechnologyTianjin 300132China School of Materials Science and Engineering North University of ChinaTaiyuan 030051China

The creep properties, microstructural characteristics and creep mechanisms of as-cast Mg-5Bi-5Sn(BT55) alloy without and with Mn(BTM550) addition were investigated via creep at 423, 448, and 473 K as well as stresses of 30, 50 and 75 MPa. The results indicate that adding Mn can result in the formation of primary and the dynamic precipitated α-Mn phases. In addition, the morphology of the precipitated Mg_(3)Bi_(2) phase and the orientation relationship between Mg_(2)Sn precipitates and α-Mg can be effectively modified. Tailoring the microstructural characteristics is responsible for the improved creep performance of BTM550 alloy. The dominant creep mechanisms in BT55 and BTM550 alloys are dislocation cross-slip and climb, respectively. Furthermore, twinning and pyramidal slip play an assisting part in both alloys during creep process.

关键词： Mg alloy Microstructural characteristics Creep properties Precipitates Dislocation

Effect of isotope on state-to-state dynamics for reactive collision reactions O(3P)+H2^+→OH^++H and O(3P)+H2^+→OH+H^+ in ground state 1^2A" and first excited 1^2A' potential energy surfaces

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Chinese Physics B 2020年第2期29卷 231-242页

作者： Juan Zhao Ting Xu Lu-Lu Zhang li-fei wang School of Science Shandong Jiaotong UniversityJinan 250357China School of Physics and Electronics Shandong Normal UniversityJinan 250358China

We carry out quantum scattering dynamics and quasi-classical trajectory（QCT） calculations for the O+H2+ reactive collision in the ground（12 A"）.nd first excited（12 A’） potential energy *** calculate the reaction probabilities of O+H2+（v=0,j=0）→OH++H and O+H2+（v=0,j=0）→OH+H+reaction for total angular momentum J=*** results calculated by QCT are consistent with those from quantum mechanical wave *** the QCT method,we generate in the center-of-mass frame the product state-resolved integral cross-sections（ICSs）;two commonly used generalized polarization-dependent differential cross-sections（PDDCS s）,（2π/σ）(dσ00/dωt),（2π/σ）(dσ20/dωt));and three angular distributions of the product rotational vectors,p（θr）,P（φr）,and p（θr,φr）.We discuss the influence on the scalar and vector properties of the potential energy surface,the collision energy,and the isotope *** there are deep potential wells in these two potential energy surfaces,their kinetic characteristics are similar to each other and the isotopic effect is not ***,the well depths and configurations of the two potential energy surfaces are different,so the effects of isotopic substitution on the integral cross-section and the rotational polarization of product are different.

关键词： quasi-classical trajectory state-to-state isotopic substitution rotational polarization of product