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Spherical cavity-expansion model for penetration of reinforced-concrete targets

Acta Mechanica Sinica 2019年第4期35卷 535-551页

作者： y.J.Deng W.J.song X.W.Chen Institute of Systems Engineering China Academy of Engineering PhysicsP.O.Box 919-416Mianyang 621999China Shock and Vibration of Engineering Materials and Structures Key Laboratory of Sichuan Province Mianyang 621000China Department of Civil Engineering and Architecture Southwest University of Science and TechnologyMianyang 621000China Department of Mechanics and Engineering Science College of EngineeringPeking UniversityBeijing 100871China Advanced Research Institute for Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China State Key Lab of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

The feature of reinforcing bars is introduced into dynamic cavity-expansion theory. Based on the elastic-plastic response penetration model of plain (i.e., unreinforced) concrete (Forrestal and Tzou, 1997), a dynamic spherical cavity-expansion penetration model for reinforced-concrete targets is developed with consideration of the circumferential restriction effect derived from reinforcing bars in the crushed region. The theoretical solution and simplified calculation formula for the cavity radial stress in incompressible and compressible reinforced concrete are obtained by introducing a reinforcement ratio as the volume fraction of rebars in the concrete target. A damping function is presented to describe the restriction effect of a single layer of reinforcing bars on the surrounding concrete, thus establishing a model to calculate the penetration resistance of multilayer reinforced-concrete targets. Compared with test data for the penetration depth, this model considering the circumferential restriction effect produces better results compared with the existing theory.

关键词： Dynamic cavity-expansion theory Reinforced concrete Penetration resistance Reinforcement ratio

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Dust-Acoustic Waves in Strongly Coupled Dusty Plasmas Containing Variable-Charge Impurities

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Chinese Physics Letters 2000年第12期17卷 890-892页

作者： XIE Bai-song HE Kai-Fen M.y.yu Key Laboratory in University for Beam Technology and Materials Modification Beijing Normal UniversityBeijing 100875 Institute of Low Energy Nuclear Physics Beijing Normal UniversityBeijing 100875(mailing address) Beijing Radiation Center Beijing 100875 Institut fur Theoretische Physik I Ruhr-Universitat Bochum0-44780 BochumGermany

A relatively self-consistent theory of dust-acoustic waves in the strongly coupled dusty plasmas containing variable-charge impurities is *** physical processes such as dust elastic relaxation and dust charge relaxation are taken into *** is shown that the negative dispersion of dust-acoustic waves due to the strong correlation of dusts is enhanced in the presence of dust-neutral collisions.

关键词： relaxation charge Strongly

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Zero-Point Motions in Trans-Polyacetylene

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Chinese Physics Letters 1998年第9期15卷 674-676页

作者： FU Rong-tang RAO Xue-song SUN Xin y.Kawazoe Department of Physics Fudan UniversityShanghai 2004331 Institute for Materials Research Tohoku UniversitySendai 980-77Japan

In order to substantiate the applicability of the Takayama-Lin-Liu-Maki model to conducting polymer,the Su-Schrieffer-Heeger model is generalized to include the effects of lattice zero-point motions on electronic *** the treatment of the white-noise approximation,some significant electronic properties of Peierls-Fröhlich states are *** finding shows that the correlation of lattice motions suppresses the effects of zero-point motions on the electronic properties more seriously.

关键词： properties lattice electronic

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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

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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

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Extracellular vesicle activities regulating macrophage- and tissue-mediated injury and repair responses

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Acta Pharmaceutica Sinica B 2021年第6期11卷 1493-1512页

作者： Qian Hu Christopher J.Lyon Jesse K.Fletcher Wenfu Tang Meihua Wan tony y.Hu Department of Integrated Traditional Chinese and Western Medicine West China HospitalSichuan UniversityChengdu 610041China Center of Cellular and Molecular Diagnosis Tulane University School of MedicineNew OrleansLA 70112USA Department of Biochemistry&Molecular Biology Tulane University School of MedicineNew OrleansLA 70112USA

Macrophages are typically identified as classically activated(M1) macrophages and alternatively activated(M2) macrophages,which respectively exhibit pro-and anti-inflammatory phenotypes,and the balance between these two subtypes plays a critical role in the regulation of tissue inflammation,injury,and repair *** studies indicate that tissue cells and macrophages interact via the release of small extracellular vesicles(EVs) in processes where EVs released by stressed tissue cells can promote the activation and polarization of adjacent macrophages which can in turn release EVs and factors that can promote cell stress and tissue inflammation and injury and vice *** review discusses the roles of such EVs in resulating such interactions to influence tissue inflammation and injury in a number of acute and chronic inflammatory disease conditions,and the potential applications,advantage and concerns for using EV-based therapeutic approaches to treat such conditions,including their potential role of drug carriers for the treatment of infectious diseases.

关键词： Extracellular vesicles Macrophage Tissue injury Inflammatory disease Interaction loop Stem cell Sepsis Targeted therapy

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Fruit Tree Disease Recognition Based on Residual Neural Network and Attention Mechanism

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Journal of Artificial Intelligence and Technology 2024年第2期4卷 145-152页

作者： Xiedong song Vladimir y.Mariano College of Computing and Information Technologies National UniversityManilaPhilippines School of Computer Science and Engineering JiNing UniversityJiNing 273155China

Fruit growing has played a huge role in solving food supply issues in many ***,the yield and quality of fruits can be affected by various diseases,and thus timely and accurate identification of disease conditions is particularly ***,using image recognition and object detection technology to diagnose fruit tree diseases has become a research hotspot in forestry *** neural networks eliminate the preprocessing of manual feature selection and have high recognition ***,it is not easy to train due to the risk of gradient *** order to achieve better recognition effect,this research addresses the problem of applying small-scale data samples through data enhancement and transfer learning,and it optimizes the model by combining the two main attention mechanisms of SE and CBAM with *** experiments,it is found that the CBAM ResNet50 model has the best effect,improving the application performance of the studied model in actual scenarios.

关键词： attention mechanism disease recognition of fruit trees ResNet transfer learning

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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

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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

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Patient Feedback for Acupuncture Practice Improvement:A Survey from Mayo Clinic

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Chinese Journal of Integrative Medicine 2017年第11期23卷 816-821页

作者： Barbara S Thomley Saswati Mahapatra Brent A Bauer Molly J Mallory LI Guang-xi Alexander Do tony y Chon Division of Operations Mayo Clinic HospitalAZ(85054)United States Integrative Medicine and Health Division of General Internal MedicineMayo ClinicMN(55902)United States

Objective： To understand patient satisfaction with acupuncture appointment duration for the first and subsequent appointments in the plan of care, time spent with the acupuncture provider, willingness to pay for longer duration appointments, and lack of insurance coverage. Methods： Patients who were referred for an acupuncture consult to the Center for Integrative Medicine at Mayo Clinic were asked to participate in the survey in August 2014. Patients were given paper survey at time of appointment check-in and entered into Research Electronic Data Capture Survey database tool to reveal patient-reported outcomes. Results： In total, 104 of 329 patients receiving acupuncture treatment responded to the survey with a 32% response rate. Insight and recommended changes to the duration of the initial and subsequent appointments were obtained. Most patients reported that time spent with the provider（76 cases, 74%） and appointment length（74 cases, 68%） were ＂just right＂. Seventy cases（70%） of respondents indicated that they wanted longer treatment. Patients reported return appointments with duration of 30 min was not enough. Fifty-three patients（62%） were willing to pay for additional costs not covered by insurance. Conclusions： We used patient feedback to assess the acupuncture practice in a complementary and integrative medicine program. Most patients referred for the acupuncture consult appeared to be satisfied with the current level of practice. These findings were used to establish a quality improvement plan that may be implemented to improve patient satisfaction with the acupuncture practice.

关键词： care survey health integrative medicine acupuncture practice

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