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Heavy Metals in Brown Rice(Oryza sativa L.) and Soil After Long-Term Irrigation of Wastewater Discharged from Domestic Sewage Treatment Plants

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Pedosphere 2011年第5期21卷 621-627页

作者： B.y.CHUNG C.H.song B.J.PARK J.y.CHO Advanced Radiation Technology Institute Korea Atomic Energy Research Institute(KAERI) Korea Testing & Research Institute(KTR) Department of Horticultural Science Chungbuk National University Department of Bio-environmental Chemistry Chonbuk National University

A pot experiment was conducted in a plastic film house to evaluate the translocation and uptake of heavy metals(Pb,Cd,Cu,and Zn) into brown rice(Oryza sativa L.) and the heavy metals residues in soils which had previously been irrigated with domestic wastewater for a long time(3 years).The range of Pb,Cd,Cu,and Zn was 5.10 ± 0.01,0.105 ± 0.017,5.76 ± 0.42,and 23.56 ± 1.40 mg kg-1,respectively in the domestic wastewater-irrigated soil,and 0.370 ± 0.006,0.011 ± 0.001,0.340 ± 0.04,and 2.05 ± 0.18 mg kg-1,respectively,in the domestic wastewater-irrigated brown *** results indicated that application of domestic wastewater to arable land slightly increased the levels of Pb,Cd,Cu,and Zn in soil and brown rice(P y metals in brown rice were lower than the recommended tolerable levels proposed by the Joint FAO/WHO Expert Committee on Food ***,the continuous monitoring and pollution control of hazardous materials from domestic wastewater are needed in order to prevent excessive build-up of heavy metals in the food chain.

关键词： accumulation domestic wastewater ground water irrigation P2O5 total N

Microstructure and Strain Hardening of a Friction Stir Welded High-Strength Al–Zn–Mg Alloy

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Acta Metallurgica Sinica(English Letters) 2014年第4期27卷 723-729页

作者： A.H.Feng D.L.Chen Z.y.Ma W.y.Ma R.J.song School of Materials Science and Engineering Tongji University State Key Laboratory of Advanced Welding Production Technology School of Materials Science and EngineeringHarbin Institute of Technology Department of Mechanical and Industrial Engineering Ryerson UniversityTorontoON M5B 2K3Canada Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences

Microstructural evolution and strain hardening behavior of a friction stir welded（FSWed） high-strength7075Al-T651 alloy were *** nugget zone was observed to consist of fine and equiaxed recrystallized grains with a low dislocation density and free of original precipitates,but containing uniformly distributed *** strength,joint efficiency,and ductility of the FSWed joints increased with increasing welding speed.A joint efficiency of ＊91% was achieved at a welding speed of 400 mm/min and rotational rate of 800 r/min,while the ductility remained basically the same as that of the base *** was no obvious strain rate sensitivity observed in both base metal and welded *** both the base metal and FSWed joints exhibited stage III and IV hardening characteristics,the hardening capacity,strain hardening exponent,and strain hardening rate all increased after friction stir welding.

关键词： Aluminum alloy Friction stir welding Mechanical properties Strain hardening

AAV-mediated expression of p65shRNA and bone morphogenetic protein 4 synergistically enhances chondrocyte regeneration

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中国组织工程研究 2025年第17期29卷 3537-3547页

作者： yu yangyi song Zhuoyue Lian Qiang Ding Kang Li Guangheng Shenzhen Key Laboratory of Musculoskeletal Tissue Reconstruction and Function Restoration Division of Adult Joint Reconstruction and Sports MedicineDepartment of Orthopedic SurgeryShenzhen People’s Hospital(The Second Clinical Medical College Jinan UniversityThe First Affiliated HospitalSouthern University of Science and Technology)Shenzhen 518020Guangdong ProvinceChina Department of Orthopedics Zhengzhou Orthopedics HospitalZhengzhou 450000Henan ProvinceChina Department of Orthopedics Shenzhen Pingle Orthopedics HospitalShenzhen 518000Guangdong ProvinceChina

BACKGROUND:Adeno-associated virus(AAV)gene therapy has been proven to be reliable and safe for the treatment of osteoarthritis in recent ***,given the complexity of osteoarthritis pathogenesis,single gene manipulation for the treatment of osteoarthritis may not produce satisfactory *** studies have shown that nuclear factorκB could promote the inflammatory pathway in osteoarthritic chondrocytes,and bone morphogenetic protein 4(BMP4)could promote cartilage ***:To test whether combined application of AAV-p65shRNA and AAV-BMP4 will yield the synergistic effect on chondrocytes regeneration and osteoarthritis ***:Viral particles containing AAV-p65-shRNA and AAV-BMP4 were *** efficacy in inhibiting inflammation in chondrocytes and promoting chondrogenesis was assessed in vitro and in vivo by transfecting AAV-p65-shRNA or AAV-BMP4 into *** experiments were divided into five groups:PBS group;osteoarthritis group;AAV-BMP4 group;AAV-p65shRNA group;and BMP4-p65shRNA 1:1 *** were collected at 4,12,and 24 weeks *** staining,including safranin O and Alcian blue,was applied after collecting articular ***,the optimal ratio between the two types of transfected viral particles was further investigated to improve the chondrogenic potential of mixed cells in *** AND CONCLUSION:The combined application of AAV-p65shRNA and AAV-BMP4 together showed a synergistic effect on cartilage regeneration and osteoarthritis *** cells transfected with AAV-p65shRNA and AAV-BMP4 at a 1:1 ratio produced the most extracellular matrix synthesis(Py,we also discovered that the combined therapy had the maximum effect when the two viruses were administered in equal *** either p65shRNA or BMP4

关键词： osteoarthritis adeno-associated virus bone morphogenetic protein 4 p65-short hairpin RNA gene therapy short hairpin RNA transforming growth factor-β1 extracellular matrix articular cartilage chondrocytes.

MOF-derived ZrO_(2)/C-polyvinylidene fluoride composite towards negative permittivity regulation mechanism

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Journal of Materials Science & Technology 2024年第12期179卷 50-56页

作者： X.T.song G.H.Fan y.Liu R.H.Fan Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) Jinan 250061China Institute of Advanced Electrical Materials Qingdao University of Science&TechnologyQingdao 266042China College of Ocean Science and Engineering Shanghai Maritime UniversityShanghai 201306China

Composites featuring negative permittivity have garnered significant attention for their potential in novel capacitance designs,coil-less electrical inductors,and electromagnetic shielding *** this study,we prepared polyvinylidene fluoride(PVDF)matrix composites filled with ZrO_(2)/C nanoparticles de-rived from metal-organic frameworks(MOFs)via a hot-pressing *** an increase in the ZrO_(2)/C content to 30 wt.%,electrical percolation was observed,accompanied by a transition mechanism from hopping conduction to metal-like *** enabled the realization of ZrO_(2)/C/PVDF composites with tailorable negative permittivity properties,attributed to the plasmonic oscillation of free electrons in the composites beyond the percolation threshold(30 wt.%).Furthermore,the permittivity transition along to a shift in the electrical behavior of the percolative composites from capacitive to *** explored the regulatory mechanism behind the negative permittivity in this random composite system,and our findings highlight the potential of these tunable negative permittivity media as promising candi-dates for diverse electromagnetic applications.

关键词： Negative permittivity Electrical properties Plasma oscillation Polymeric composites

Material and structural instabilities of single-wall carbon nanotubes

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Acta Mechanica Sinica 2008年第3期24卷 285-288页

作者： J.Wu K.C.Hwang J.song y.Huang FML Department of Engineering MechanicsTsinghua UniversityBeijing 100084China Department of Mechanical Science and Engineering University of Illinois1206 W.Green StreetUrbanaIL 61801USA Department of Civil and Environmental Engineering and Department of Mechanical Engineering Northwestern UniversityEvanstonIL 60208USA

The nonlinear atomistic interactions usually involve softening behavior. Instability resulting directly from this softening are called the material instability, while those unrelated to this softening are called the structural instability. We use the finite-deformation shell theory based on the interatomic potential to show that the tension instability of single-wall carbon nanotubes is the material instability, while the compression and torsion instabilities are structural instability.

关键词： Carbon nanotubes Instability

A NOVEL APPROACH FOR THE PREDICTION OF SURFACE PROFILE OF OUTGOING WORKPIECE AND THE CALCULATION OF MEAN ROLL RADIUS IN ALLOy BAR ROLLING

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Acta Metallurgica Sinica(English Letters) 2007年第1期20卷 49-58页

作者： y.G. Dong W.Z. Zhang J.F. song College of Mechanical Engineering Yanshan University Qinhuangdao 066004 Ghina College of Electromechanical Engineering Harbin Institute of Technology Harbin 150001China

In alloy bar rolling process, the component of alloyed steel influenced the spread coefficient greatly, therefore, the component influence coefficient m of different alloyed steel has been determined firstly to calculate the maximum spread. Then the curvature radius of stress free surface and the ＂critical point on the contact boundary＂ have been solved, the surface profile of outgoing workpiece has been obtained. Furthermore, the formula of the equivalent contact section area has been proposed and the mean roll radius has been calculated. The bar rolling experiment and the rigid-plastic FEM （finite element method） simulation have been carried out to verify the novel approach. Compared with experimental data and simulation results, the novel approach can be used in setting processing parameter and design of finishing groove.

关键词： alloyed steel surface profile mean roll radius critical point rigid-plastic FEM (finite element method)

阿拉善-华北北缘晚古生代-早中生代岩浆作用:对古亚洲洋俯冲-闭合过程的制约

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岩石学报 2025年第1期41卷 66-90页

作者：曾浩宋东方肖文交李普庆中国科学院地质与地球物理研究所岩石圈演化与环境演变全国重点实验室北京100029 中国科学院地球科学研究院北京100029 中国科学院新疆生态与地理研究所干旱区生态安全与可持续发展全国重点实验室乌鲁木齐830011 中国科学院大学地球与行星科学学院北京100049

位于中亚造山带南部的阿拉善-华北北缘地区保存了丰富的晚古生代-早中生代岩浆记录,为理解古亚洲洋从俯冲至闭合的构造演化过程提供了关键信息。本文对位于内蒙古西部的甘其毛都地区的4个侵入体进行了岩相学、地球化学、锆石U-Pb年代学... 详细信息

位于中亚造山带南部的阿拉善-华北北缘地区保存了丰富的晚古生代-早中生代岩浆记录,为理解古亚洲洋从俯冲至闭合的构造演化过程提供了关键信息。本文对位于内蒙古西部的甘其毛都地区的4个侵入体进行了岩相学、地球化学、锆石U-Pb年代学和Lu-Hf同位素分析。锆石U-Pb定年表明这些岩体分别形成于早二叠世(283±3Ma、273±5Ma、272±5Ma)和中三叠世(238±3Ma)。早二叠世岩体以石英闪长岩和闪长玢岩为主,富集轻稀土与大离子亲石元素,亏损高场强元素Nb、Ta等,Hf同位素显著亏损(-4.0~+15.6)。它们可能是由俯冲板片流体交代地幔楔部分熔融形成的基性岩浆经分离结晶演化而成。中三叠世侵入体为花岗闪长岩,轻重稀土元素强烈分异,锆石ε_(Hf)(t)值均为正值(+5.0~+8.5),可能代表了碰撞造山阶段新生下地壳物质部分熔融的产物。在此基础之上,本文系统收集并分析了阿拉善-华北北缘地区晚古生代-早中生代岩浆岩的时空分布规律与地球化学特征,以限定其构造背景与深部动力学过程。结合前人研究成果提出:石炭纪时期,古亚洲洋向南俯冲至阿拉善-华北克拉通之下并不断向北后撤;至早二叠世,俯冲板片转变为前进式俯冲,整体处于挤压环境,发育大规模岩浆活动与弧背前陆盆地;早-中三叠世,古亚洲洋闭合,阿拉善-华北克拉通沿索伦缝合带与北侧的中亚弧增生体系发生碰撞-拼贴。

关键词：阿拉善华北北缘晚古生代-早中生代古亚洲洋俯冲-闭合

Experimental and Numerical Investigation on Impact Performance of Carbon Reinforced Aluminum Laminates

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Journal of Materials Science & Technology 2010年第4期26卷 327-332页

作者： S.H. song y.S. Byun T.W. Ku W.J. song J. Kim B.S. Kang National Core Research Center Pusan National University Busan 609-735 Korea Dept. of Aerospace Engineering Pusan National University Busan 609-735 Korea Industrial Liaison Innovation Cluster Pusan National University Busan 609-735 Korea

It is known that fiber metal laminates （FML） as one of hybrid materials with thin metal sheets and fiber/epoxy layers have the characteristics of the excellent damage tolerance, fatigue and impact properties with a relatively low density. Therefore, the mechanical components using FML can contribute the enhanced safety level of the sound construction toward the whole body. In this study, the impact performance of carbon reinforced aluminum laminates （CARAL） is investigated by experiments and numerical simulations. Drop weight tests are carried out with the weight of 4.7 kg at the speed of 1 and 2 m/s, respectively. Dynamic non-linear transient analyses are also accomplished using a finite element analysis software, ABAQUS. The experiment results and numerical results are compared with impact load-time histories. Also, energy-time histories are applied to investigate the impact performance of CARAL.

关键词： Fiber metal laminates (FML) Carbon reinforced aluminum laminates (CARAL) Numerical simulation Impact performance

Three-dimensional guidance law based on adaptive integral sliding mode control

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Chinese Journal of Aeronautics 2016年第1期29卷 202-214页

作者： song Junhong song Shenmin Center for Control Theory and Guidance Technology Harbin Institute of Technology

For the terminal guidance problem of missiles intercepting maneuvering targets in the three-dimensional space, the design of guidance laws for non-decoupling three-dimensional engage- ment geometry is studied. Firstly, by introducing a finite time integral sliding mode manifold, a novel guidance law based on the integral sliding mode control is presented with the target acceler- ation as a known bounded external disturbance. Then, an improved adaptive guidance law based on the integral sliding mode control without the information of the upper bound on the target accel- eration is developed, where the upper bound of the target acceleration is estimated online by a designed adaptive law. The both presented guidance laws can make sure that the elevation angular rate of the line-of-sight and the azimuth angular rate of the line-of-sight converge to zero in finite time. In the end, the results of the guidance performance for the proposed guidance laws are pre- sented by numerical simulations. Although the designed guidance laws are developed for the con- stant speed missiles, the simulation results for the time-varying speed missiles are also shown to further confirm the designed guidance laws.

关键词： Adaptive control Finite-time convergence Integral sliding mode control Missile Three-dimensional guidance law