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Double-layer microwave absorber of nanocrystalline strontium ferrite and iron microfibers

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Chinese Physics B 2012年第2期21卷 541-547页

作者： Wei Chun-Yu Shen Xiang-Qian song fu-Zhan School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013China

Microwave absorption properties of the nanocrystalline strontium ferrite （SrFe12O19） and iron （α-Fe） microfibers for single-layer and double-layer structures are investigated in a frequency range of 2 GHz 18 GHz. For the singlelayer absorbers, the nanocrystalline SrFe12O19 microfibers show some microwave absorptions at 6 GHz 18 GHz, with a minimum reflection loss （RL） value of -11.9 dB at 14.1 GHz for a specimen thickness of 3.0 mm, while for the nanocrystalline α-Fe microfibers, their absorptions largely take place at 15 GHz-18 GHz with the RL value exceeding -10 dB, with a minimum .RL value of about -24 dB at 17.5 GHz for a specimen thickness of 0.7 mm. For the doublelayer absorber with an absorbing layer of α-Fe microfibers with a thickness of 0.7 mm and matching layer of SrFe12O19 microfibers with a thickness of 1.3 ram, the minimum RL value is about -63 dB at 16.4 GHz and the absorption band width is about 6.7 GHz ranging from 11.3 GHz to 18 GHz with the RL value exceeding -10 dB which covers the whole Ku-band （12.4 GHz 18 GHz） and 27% of X-band （8.2 GHz 12.4 GHz）.

关键词： nanocrystalline microfibers microwave absorber double-layer structure

Identification of similar transcriptional regulatory mechanisms in multiple cry genes in Bacillus thuringiensis HD12

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Journal of Integrative Agriculture 2017年第1期16卷 135-143页

作者： song Zhi-ru PENG Qi SHU Chang-long ZHANG Jie SUN Dong-mei song fu-ping College of Life Science and Technology Heilongjiang Bayi Agricultural University State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural Sciences

Bacillus thuringiensis subspecies morrisoni strain HD12, whose genome harbors multiple insecticidal protein-encoding genes, includes eight cry genes, as indicated by genome sequencing. This strain produces crystals that are toxic to lepidopteran species. These crystal inclusions were purified by sucrose gradients and sodium dodecyl sulphate-polyacrylamide gel electrophoresis （SDS-PAGE）, followed by liquid chromatography-mass spectrometry, and found to contain five proteins （Cry1Da, Cry1Ae, Cry1Bb, Cry1Fb, and CrylJa）. The transcriptional activities of the cry1Da, cry1Ae, cry1Bb, cry1Fb, and cry11Ja promoters indicated that transcription of crylDa is controlled by SigE; however, the other four cry genes were found to be controlled by both SigE and SigK. The activities of the crylJa and crylFb promoters were the strongest among the five genes studied. These promoters were therefore used to direct the expression of the Cry1Ac- and Cry2Ab-encoding genes concurrently in a single strain. Our findings indicate that promoters with the same transcriptional profile may be used to direct the expression of different cry genes in one strain. Our results are expected to be valuable for the construction of strains with efficient expression of multiple cry genes in order to overcome current limitations associated with the application of B. thuringiensis-based insecticides.

关键词： Bacillus thuringiensis transcription cry genes insecticide

The effects of vortex breakdown on the static rolling aerodynamics of finned slender body

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Science China(Physics,Mechanics & Astronomy) 2014年第11期57卷 2174-2176页

作者： XU KeZhe ZHANG YuFei CHEN HaiXin fu song School of Aerospace Tsinghua University

The static rolling aerodynamics of a finned slender body is numerically studied in this *** results show a nonlinear uprising of the rolling moment when the angle of attack is greater than 20°in subsonic *** vortex break down phenomenon on the"horizontal"rudders is found to be responsible for this *** introducing the geometric-equivalent angle of attack and geometric-equivalent sweep angle,the cause of the nonlinear rolling moment characteristics can be explained by the delta wing vortex breakdown analysis.

关键词： vortex breakdown rolling moment delta wing slender body

Factors Influencing Pleural Effusion after Fontan Operation:an Analysis with 95 Patients

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Chinese Medical Sciences Journal 2010年第1期25卷 38-43页

作者： song fu Zhi-cun Feng Schranz Dietmar Department of Children＇s Heart Centre BAYI Children＇s Hospital the Military General Hospital of Beijing PLA Beijing 100700 China Department of Children＇s Heart Centre Justus-Liebig-University Giessen Giessen 35385 Germany

Objective To investigate the association between preoperative,operative,and postoperative factors and persistent pleural effusion after the extracardiac Fontan procedure. Methods Ninety-five consecutive patients diagnosed with univentricular heart underwent extracardiac connection using Gore-Tax conduits at the Department of Children’s Heart Centre,Justus-Liebig-University Giessen in Germany from June 1996 to July 2007. The outcome measures were duration and volume of chest tube drainage after surgical intervention. The investigated factors included age and weight at the time of operation,anatomical diagnosis,preoperative oxygen saturation,mean pulmonary artery pressure,ventricular end-diastolic pressure,fenestration,cardiopulmonary bypass time,conduit size,postoperative pulmonary artery pressure,administration of angiotensin-converting enzyme inhibitors,and postoperative infection. Associations between these factors and persistent pleural effusion after the extracardiac Fontan procedure were analyzed. Results Every patient suffered postoperative effusion. The median duration of postoperative chest tube drainage was 9 days (range,3-69 days),and the median volume was 12 mL·kg-1·d-1 (range,2.0-37.5 mL·kg-1·d-1). Thirty-seven (38.9%) patients had pleural drainage for more than 15 days,and the volume in 35 (36.8%) patients exceeded 25 mL·kg-1·d-1. Nineteen (20%) patients required placement of additional chest tubes for re-accumulation of pleural effusion after removal of previous chest tubes. Fifteen (17.8%) patients were hospitalized again due to pleural effusion after discharge. The median length of hospital stay after the operation was 14 days (range,4-78 days). Multivariate analysis results showed that non-fenestration,low preoperative oxygen saturation,and postoperative infections were independent risk factors for prolonged duration of pleural drainage (P<0.05). Long cardiopulmonary bypass time,non-fenestration,small conduit size,and low preoperative oxygen saturat

关键词： Fontan connection pleural effusion independent risk factors

Accuracy evaluation of a new three-dimensional reproduction method of edentulous dental casts, and wax occlusion rims with jaw relation

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International Journal of Oral Science 2013年第3期5卷 155-161页

作者： fu-song Yuan Yu-Chun Sun Yong Wang Pei-Jun L Center of Digital Dentistry Peking University School and Hospital of Stomatology & National Engineering Laboratory for Digital and Material Technology of Stomatology & Research Center of Engineering and Technology for Digital Dentistry Ministry of Health

The article introduces a new method for three-dimensional reproduction of edentulous dental casts,and wax occlusion rims with jaw relation by using a commercial high-speed line laser scanner and reverse engineering software and evaluates the method’s accuracy in *** method comprises three main steps：（i）acquisition of the three-dimensional stereolithography data of maxillary and mandibular edentulous dental casts and wax occlusion rims;（ii）acquisition of the three-dimensional stereolithography data of jaw relations;and（iii）registration of these data with the reverse engineering software and completing *** evaluate the accuracy of this method,dental casts and wax occlusion rims of 10 edentulous patients were *** lengths of eight lines between common anatomic landmarks were measured directly on the casts and occlusion rims by using a vernier caliper and on the three-dimensional computerized images by using the software measurement *** direct data were considered as the true *** paired-samples t-test was used for statistical *** mean differences between the direct and the computerized measurements were mostly less than 0.04 mm and were not significant（P.0.05）.Statistical significance among 10 patients was assessed using one-way analysis of variance（P,0.05）.The result showed that the 10 patients were considered statistically no ***,accurate three-dimensional reproduction of the edentulous dental casts,wax occlusion rims,and jaw relations was *** proposed method enables the visualization of occlusion from different views and would help to meet the demand for the computer-aided design of removable complete dentures.

关键词： accuracy computer-aided design/computer-aided manufacturing complete denture jaw relation line laser scanner reverse engi neeri ng software

Artificial modification of Earth's radiation belts by ground-based very-low-frequency(VLF)transmitters

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Science China Earth Sciences 2022年第3期65卷 391-413页

作者： Binbin NI Man HUA Xudong GU song fu Zheng XIANG Xing CAO Xin MA Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China Chinese Academy of Sciences Center for Excellence in Comparative Planetology Hefei 230026China

Wave-particle interactions play a fundamental role in the dynamic variability of Earth’s donut-shaped radiation belts that are highly populated by magnetically trapped energetic particles and characteristically separated by the slot devoid of high energetic *** to the continuous accumulation of high-quality wave and particle measurements from multiple satellites in geospace,the important contribution of ground-based very-low-frequency(VLF)transmitter waves to the electron dynamics in the near-Earth space has been unprecedently advanced,in addition to those established findings of the significant effects of a variety of naturally occurring magnetospheric *** paper focuses on the artificial modification of Earth’s inner radiation belt and slot by artificial VLF transmitter *** review the global distributions of VLF transmitter waves in geospace,their scattering effects on radiation belt electrons in terms of both theoretical and observational analyses,and diffusion simulation results of wave-particle interactions along with data-model *** start with a brief review of the radiation belt electron dynamics and an introduction of anthropogenic VLF transmitter ***,we review the global morphology of in situ VLF transmitter waves corresponding to different transmitter locations,including their day-night asymmetry,geographic distributions,seasonal and geomagnetic activity dependence,and wave propagation *** theoretical and observational analyses of electron scattering effects by VLF transmitter waves are then reviewed to approach the underlying physics that can modulate the spatio-temporal variations of the electron radiation *** Fokker-Planck electron diffusion simulations and their comparisons with realistic satellite observations clearly indicate that VLF transmitter emissions can effectively remove energetic electrons to produce a radially bifurcated electron belt,thereby quantitatively confirmin

关键词： VLF transmitters Wave-particle interactions Electron precipitation Earth’s radiation belts Flux bifurcation

A data assimilation-based forecast model of outer radiation belt electron fluxes

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Earth and Planetary Physics 2023年第6期7卷 620-630页

作者： Yuan Lei Xing Cao BinBin Ni song fu TaoRong Luo XiaoYu Wang Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China Chinese Academy of Sciences Center for Excellence in Comparative Planetology Hefei 230026China

Because radiation belt electrons can pose a potential threat to the safety of satellites orbiting in space,it is of great importance to develop a reliable model that can predict the highly dynamic variations in outer radiation belt electron *** the present study,we develop a forecast model of radiation belt electron fluxes based on the data assimilation method,in terms of Van Allen Probe measurements combined with three-dimensional radiation belt numerical *** forecast model can cover the entire outer radiation belt with a high temporal resolution(1 hour)and a spatial resolution of 0.25 L over a wide range of both electron energy(0.1-5.0 MeV)and pitch angle(5°-90°).On the basis of this model,we forecast hourly electron fluxes for the next 1,2,and 3 days during an intense geomagnetic storm and evaluate the corresponding prediction *** model can reasonably predict the stormtime evolution of radiation belt electrons with high prediction efficiency(up to~0.8-1).The best prediction performance is found for~0.3-3 MeV electrons at L=~3.25-4.5,which extends to higher L and lower energies with increasing pitch *** results demonstrate that the forecast model developed can be a powerful tool to predict the spatiotemporal changes in outer radiation belt electron fluxes,and the model has both scientific significance and practical implications.

关键词： Earth’s outer radiation belt data assimilation electron flux forecast model performance evaluation

3D Fe-Rich Phases Evolution and Its Effects on the Fracture Behavior of Al-7.0Si-1.2Fe Alloys by Mn Neutralization

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Acta Metallurgica Sinica(English Letters) 2022年第1期35卷 163-175页

作者： Dong-fu song Yu-Liang Zhao Zhi Wang Yi-Wang Jia Dao-Xi Li Ya-Nan fu Da-Tong Zhang Wei-Wen Zhang National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials South China University of TechnologyGuangzhou510641China Guangdong Provincial Key Laboratory of Metal Toughening Technology and Application Institute of New MaterialsGuangdong Academy of SciencesGuangzhou510650China School of Mechanical Engineering Dongguan University of TechnologyDongguan523808China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai201204China

The evolution of the 3D Fe-rich phases of Al-7.0Si-1.2Fe alloys with different Mn contents was visualized and characterized using synchrotron X-ray computed tomography,and the effect of Fe-rich phases with typical morphologies on the fracture behavior during tensile testing was *** results showed that the Fe-rich phase changed from platelet-likeβ-Al_(5) Fe Si intoα-Al_(15)(Fe Mn)_(3)Si_(2)with various morphologies after the addition of *** Mn addition not only significantly reduced the volume fraction,equivalent diameter and interconnectivity of the Fe-rich phase but also greatly increased the sphericity,surface thickness,and distribution of the mean curvature and surface ***,the equivalent diameter ofα-Al_(15)(FeMn)_(3)Si_(2)had an inverse exponential function relationship with its *** 3D morphology ofα-Al_(15)(FeMn)_(3)Si_(2)can be summarized as massive and regular polyhedrons,hollow and regular polyhedrons,and multibranched *** fraction of the different 3D morphologies in each alloy is related to the Mn content,where excess Mn increased the number and volume fraction of the large Fe-rich particles with a low *** ductility of each alloy was significantly improved by the addition of Mn but gradually decreased when the Mn/Fe ratio exceeded *** increase in largeα-Al_(15)(Mn Fe)_(3)Si_(2)with a low sphericity was the main reason for the decreased ductility of alloys with a high Mn content.

关键词： Synchrotron X-ray tomography Fe-rich phase 3D morphology Fracture behavior

Effects of cloned tumstatin-related and angiogenesis-inhibitory peptides on proliferation and apoptosis of endothelial cells

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Chinese Medical Journal 2008年第22期121卷 2324-2330页

作者： ZHANG Guang-mei ZHANG Ying-mei fu song-bin LIU Xing-han fu Xue YU Yan ZHANG Zhi-yi Department of Obstetrics & Gynaecology First Clinical College Harbin Medical University Harbin Heilongjiang 150001 China Central Laboratory First Clinical College Harbin Medical University Harbin Heilongjiang 150001 China Bio-pharmaceutical Key Laboratory of Heilongjiang Province Incubator of State Key Laboratory Basic College Harbin Medical University Harbin Heilongjiang 150086 China Department of Chemotherapy Third Clinical College Harbin Medical University Harbin Heilongjiang 150040 China Department of Rheumatology First Clinical College Harbin Medical University Harbin Heilongjiang 150001 China

Background Tumstatin is a recently developed endogenous vascular endothelial growth inhibitor that can be applied as an anti-angiogenesis and antineoplastic agent. The study aimed to design and synthesize the small molecular angiogenesis inhibition-related peptide （peptide 21）, to replicate the structural and functional features of the active zone of angiogenesis inhibition using tumstatin and to prove that synthesized peptide 21 has a similar activity： specifically inhibiting tumor angiogenesis like tumstatin. Methods Peptide 21 was designed and synthesized using biological engineering technology. To determine its biological action, the human umbilical vein endothelial cell line ECV304, the human ovarian cancer cell line SKOV-3 and the mouse embryo-derived NIH3T3 fibroblasts were used in in vitro experiments to determine the effect of peptide 21 on proliferation of the three cell lines using the MTT test and growth curves. Transmission electron microscopy （TEM） and flow cytometry （FCM） were applied to analyze the peptide 21-induced apoptosis of the three cell lines qualitatively and quantitatively. In animal experiments, tumor models in nude mice subcutaneously grafted with SKOV-3 were used to observe the effects of peptide 21 on tumor weight, size and microvessel density （MVD）. To initially investigate the role of peptide 21, the effect of peptide 21 on the expression of vascular endothelial growth factors （VEGFs） by tumor tissue was semi-quantitatively analyzed. Results The in vitro Ml-r test and growth curves all indicated that cloned peptide 21 could specifically inhibit ECV304 proliferation in a dose-dependent manner （P 〈0.01）; TEM and FCM showed that peptide 21 could specifically induce ECV304 apoptosis （P 〈0.01）. Results of in vivo experiments showed that tumors in the peptide 21 group grew more slowly. The weight and size of the tumors after 21 days of treatment were smaller than those in the control group （P 〈0.05）, with a mean tumor inhibition rate of 67.

关键词： tumstatin angiogenesis inhibitors anti-angiogenesis ovarian neoplasms