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Scale Effects on Propeller Cavitating Hydrodynamic and Hydroacoustic Performances with Non-uniform Inflow

Chinese Journal of Mechanical Engineering 2013年第2期26卷 414-426页

作者： YANG Qiongfang wang yongsheng ZHANG Zhihong College of Marine Power Engineering Naval University of Engineering College of Science Naval University of Engineering

Considering the lack of theoretical models and ingredients necessary to explain the scaling of the results of propeller cavitation inception and cavitating hydroacoustics from model tests to full scale currently, and the insufficient reflection of the nuclei effects on cavitation in the numerical methods, the cavitating hydrodynamics and cavitation low frequency noise spectrum of three geometrically similar 7-bladed highly skewed propellers with non-uniform inflow are addressed. In this process, a numerical bridge from the multiphase viscous simulation of propeller cavitation hydrodynamics to its hydro-acoustics is built, and the scale effects on performances and the applicability of exist scaling law are analyzed. The effects of non-condensable gas（NCG） on cavitation inception are involved explicitly in the improved Sauer＇s cavitation model, and the cavity volume acceleration related to its characteristic length is used to produce the noise spectrum. Results show that, with the same cavitation number, the cavity extension on propeller blades increases with diameter associated with an earlier shift of the beginning point of thrust decline induced by cavitation, while the three decline slopes of thrust breakdown curves are found to be nearly the same. The power of the scaling law based on local Reynolds number around 0.9R section is determined as 0.11. As for the smallest propeller, the predominant tonal noise is located at blade passing frequency（BPF）, whereas 2BPF for the middle and both 2BPF and 3BPF for the largest, which shows the cavitating line spectrum is fully related to the interaction between non-uniform inflow and fluctuated cavity volume. The predicted spectrum level exceedance from the middle to the large propeller is 6.65 dB at BPF and 5.94 dB at 2BPF. Since it just differs less than 2 dB to the increment obtained by empirical scaling law, it is inferred that the scale effects on them are acceptable with a sufficient model scale, and so do the scaling

关键词： propeller cavitation inception cavitation noise scale effect cavitation model turbulence model

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Structural characteristics and geochronology of migmatites in the North Dabie Complex unit: Timing of post-collisional deformation

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Science China Earth Sciences 2018年第7期61卷 887-902页

作者： yongsheng wang Qiao BAI Bingfei YANG School of Resources and Environmental Engineering Hefei University of Technology

Extensive migmatization and large-scale post-collisional intrusions occurred in the Dabie orogen, east-central China,during the Early Cretaceous, characterized by distinct deformation preserved in migmatites in the North Dabie Complex *** North Dabie Complex unit can be subdivided into three areas based on detailed field observations： the north of the Tiantangzhai pluton, the Luotian area and the Yuexi area. Banded migmatites crop out in the north of the Tiantangzhai pluton while anisotropically deformed migmatites occur in the Luotian area, and both types coexist in the Yuexi area. Microscopy reveals similar micro-structures are in migmatites from the north of the Tiantangzhai pluton, the Yuexi area and border of the Luotian area, while static recrystallization appears in migmatites from the core of the Luotian area. The Lattice-Preferred Orientation of dynamically recrystallized quartz grains in the migmatites are measured using electron backscattered diffraction,revealing prism slip or slip in migmatite from the north of the Tiantangzhai pluton and the Yuexi area and in one sample from the Luotian area. A Type I crossed girdle is developed in another sample from the Luotian area, indicating top-to-the-SE shearing that developed under greenschist facies conditions. Zircon U-Pb dates from four migmatites reveal that mainly Early Cretaceous ages are from the north of the Tiantangzhai pluton, only four Early Cretaceous ages are from the Luotian area, and all zircons from the Yuexi area record Indosinian metamorphic ages. Although zircon U-Pb results show multiple migmatization events, all samples record a migmatization age of about 132 Ma, suggesting an orogen-scale event at that time. The subsolidus deformation in migmatites indicates that deformation were soon after migmatization. Overall, this study shows that deformation in migmatites of the North Dabie Complex unit occurred somewhat later than the migmatization（132 Ma） at about 131 Ma. The most likely mecha

关键词： The North Dabie Complex unit Migmatite Structural evidence Zircon U-Pb dating

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Advances in regional nodal management of early-stage breast cancer

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Chinese Journal of Cancer Research 2024年第2期36卷 215-225页

作者： Zhao Bi yongsheng wang Breast Cancer Center Shandong Cancer Hospital and InstituteShandong First Medical University and Shandong Academy of Medical SciencesJinan 250017China

With the continuous improvement of systemic treatment, reasonable local regional control of early-stage breast cancer can be translated into survival benefits. The optimization of regional nodal management in patients with limited sentinel lymph node(SLN) metastasis needs to be weighed by surgical complications, regional recurrence risk, and lymph node status, as well as other escalating treatment(systemic/radiotherapy) that may result from deescalating surgery. With the effective support and supplementation of systemic therapy and radiotherapy, the management of axillary surgery is developing in a de-escalating trend. The widespread application of neoadjuvant therapy has contributed to optimizing the management of patients with clinically node-negative/imaging nodepositive disease. In clinical practice, it is necessary to consider the residual tumor burden of regional lymph nodes when formulating the optimal irradiation fields in patients with limited positive SLN without axillary lymph node dissection. The combined application of genomic tests and American College of Surgeons Oncology Group Z0011/AMAROS criteria could provide patients with a better strategy of dual de-escalation treatment, which includes the de-escalation of both axillary surgery and systemic treatment. In the era of sentinel lymph node biopsy(SLNB), the regional nodal management of breast cancer should adhere to the concept of “updating ideas, making bold assumptions, and carefully seeking proof”, make full use of the benefits of systemic therapy and radiotherapy to reduce the scope of surgery and complications, and expand the “net benefit” of efficacy and quality of life. This review discusses the optimization of regional nodal management in the era of SLNB, in order to provide reference information for clinicians.

关键词： Breast cancer sentinel lymph node biopsy internal mammary lymph node radiotherapy surgery

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Multidisciplinary integrated design of long-range ballistic missile using PSO algorithm

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Journal of Systems Engineering and Electronics 2020年第2期31卷 335-349页

作者： ZHENG Xu GAO Yejun JINGWuxing wang yongsheng Department of Aerospace Engineering Harbin Institute of TechnologyHarbin 150001China The 28th Research Institute of China Electronics Technology Group Corporation Nanjing 210007China Beijing Aerospace Long-march Flying Vehicle Institute Beijing 100076China Beijing Aerospace Technology Institute Beijing 100074China

In the case of the given design variables and constraint functions, this paper is concerned with the rapid overall parameters design of trajectory, propulsion and aerodynamics for long-range ballistic missiles based on the index of the minimum take-off *** contrast to the traditional subsystem independent design, this paper adopts the research idea of the combination of the subsystem independent design and the multisystem integration ***, the trajectory, propulsion and aerodynamics of the subsystem are separately designed by the engineering design, including the design of the minimum energy trajectory, the computation of propulsion system parameters, and the calculation of aerodynamic coefficient and dynamic derivative of the missile by employing the software of missile DATCOM. Then, the uniform design method is used to simplify the constraint conditions and the design variables through the integration design, and the accurate design of the optimized variables would be accomplished by adopting the uniform particle swarm optimization(PSO) algorithm. Finally, the automation design software is written for the three-stage solid ballistic missile. The take-off mass of 29 850 kg is derived by the subsystem independent design, and 20 constraints are reduced by employing the uniform design on the basis of 29 design variables and 32 constraints, and the take-off mass is dropped by 1 850 kg by applying the combination of the uniform design and PSO. The simulation results demonstrate the effectiveness and feasibility of the proposed hybrid optimization technique.

关键词： ballistic missile independent design multidisciplinary integrated design uniform design particle swarm optimization(PSO)

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Enhanced microwave absorption performance of MOF-derived hollow Zn-Co/C anchored on reduced graphene oxide

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Chinese Physics B 2021年第6期30卷 610-616页

作者： Yue wang Dawei He yongsheng wang Key Laboratory of Luminescence and Optical Information Ministry of EducationInstitute of Optoelectronic TechnologyBeijing Jiaotong UniversityBeijing 100044China

Composite materials assembled by metal/carbon nanoparticles and 2 D layered flakes can provide abundant interfaces,which are beneficial for high-performance microwave absorbers. Herein, Zn-Co/C/RGO composites, composed of ZnCo metal-organic framework-derived Zn-Co/C nanoparticles and reduced graphene oxide(RGO), were obtained through a facile method. The multilayer structure was due to the introduction of hollow Zn-Co/C nanoparticles in the RGO sheets. ZnCo/C nanoparticles provided abundant polarization and dipole centers on the RGO surface, which enhanced the microwave absorption abilities. Different concentrations of RGO were introduced to optimize impedance matching. The minimum reflection loss(R_(L)) of Zn-Co/C/RGO with a thickness of 1.5 mm reached-32.56 dB with the bandwidth corresponding to R_(L) at-10 dB, which can reach 3.92 GHz, while a minimum R_(L) of-47.15 dB at 11.2 GHz was also obtained at a thickness of 2.0 mm. The electromagnetic data demonstrate that Zn-Co/C/RGO presented excellent absorption performance and has potential for application in the microwave absorption field.

关键词： microwave absorption metal nanoparticles metal-organic framework(MOF) reduced graphene oxide

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Synthesis and properties of copolymers based on 5,6-dinitrobenzothiadiazole with low band gap and broad absorption spectra

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Science China Chemistry 2011年第4期54卷 617-624页

作者： wang Fei LIU yongsheng WAN XiangJian ZHOU JiaoYan CHEN yongsheng Key Laboratory for Functional Polymer Materials and Centre for Nanoscale Science and Technology Institute of Polymer ChemistryCollege of ChemistryNankai UniversityTianjin 300071China

One polythiophene derivative PT3T and two low band gap copolymers,PBTT-T3T and PBTT,with different ratios of 5,6-dini-trobenzothiadiazole as the acceptor unit in the polymer backbone have been synthesized by Pd-catalyzed Stille-coupling *** stability,X-ray diffraction analyses,UV-vis absorption spectra,photoluminescence spectra and electrochemical properties of the copolymers were *** band gap estimated from UV-vis-NIR spectra of the copolymers films varied from 1.39 to 1.94 *** these copolymers,the films of PBTT-T3T and PBTT,which contain the 5,6-dinitrobenzothiadiazole unit,cover a broad wavelength range in the visible and near-infrared region from 400 to 1000 nm with the maximal peak absorption around 700 nm,which is exactly matched with the maximum in the photon flux of the sun.

关键词： copolymer broad absorption low band gap charge transfer

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Detrital zircon U-Pb dating in the southern Hefei Basin: Evidence for exhumation of HP-UHP rocks of the Dabie Orogen

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Science China Earth Sciences 2020年第7期63卷 954-968页

作者： yongsheng wang Qiao BAI Ziqiang TIAN Hui DU School of Resources and Environmental Engineering Hefei University of TechnologyHefei 230009China

The Hefei Basin of eastern China developed in response to uplift of the Dabie Orogen,and zircon dating can be used to assess the exhumation history of the *** were collected from samples of the Lower Jurassic Fanghushan Formation and Middle Jurassic Sanjianpu Formation in the southern Hefei Basin,and mica-quartz schist and biotite granite gneiss from the Susong Complex of the Dabie *** zircon U-Pb dating was undertaken using laser ablation-inductively coupled plasma-mass *** detrital zircons from conglomerates of the Fanghushan Formation and from clasts within the conglomerates have age-frequency distributions with the main clusters between 2.0 and 1.8 Ga,similar to age data of the Susong *** the other hand,the zircons of the Fanghushan Formation do not show the age cluster at 1000–900 Ma that characterizes zircons in the underlying metasediments of the lower Paleozoic Foziling Group.A cluster of Triassic zircon ages also appears in the arkosic sandstones of the Fanghushan *** data indicate that the provenance of the Fanghushan Formation was a mixture of high-pressure(HP)and ultrahigh-pressure(UHP)Triassic metamorphic rocks,Paleozoic magmatic rocks,and the Susong Complex,but not the lower Paleozoic Foziling Group even though it directly underlies the sediments of the Hefei *** samples from the Sanjianpu Formation show zircon age clusters at 797 and 791 Ma(middle Neoproterozoic)and 226 Ma(Triassic),and again,these are markedly different from the age clusters that characterize the Foziling *** seems,therefore,that despite the Foziling Group being at the surface in the underwater depositional area of the Hefei Basin,it was not exposed in the source area of the Hefei basinal sediments during the Jurassic,and there are two possible reasons for ***,the exhumation of the Dabie Orogen was directed partly towards the north,in the process of which some of the Foziling Group was ***,the Susong Compl

关键词： Dabie Orogen Exhumation of HP-UHP rocks Hefei Basin Lower-Middle Jurassic Zircon dating

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Investigation of the solute transportation coupled with heat transfer and fluid flow during twin-roll strip casting process

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Acta Metallurgica Sinica(English Letters) 2009年第5期22卷 345-352页

作者： yongsheng wang Chenxi JI Jiongming ZHANG Xinhua wang Wanjun wang School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China Shougang Group Beijing 100043 China Jiuquan Iron ＆ Steel （Group） Co. Ltd. Jiayuguan 735100 China

Mathematical model of solute [C] distribution in twin-roll strip casting process has been setup successfully with Calcosoft for the first time. Simulation result shows that in the center of the molten steel pool between the two rolls there is a vortex flow, which is a solute enriched area. But the highest solute concentration position is at the solidification front of the columnar grain zone near the cooling roll surface. Another solute enriched position is in the back flow above the nip point. Combined with the formation mechanism of microstruoture in final as cast strip, analysis shows that solute enriched area is in the transitional area between columnar and equiaxed grain zone.

关键词： Twin-roll strip casting Solute field simulation Macrosegregation

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Chinese Continental Paleocene-Eocene Boundary and Its Correlation

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Acta Geologica Sinica(English Edition) 2011年第2期85卷 443-451页

作者： wang Yuanqing TONG yongsheng LI Qian Key Laboratory of Evolutionary Systematics of Vertebrates Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China

Recent paleontological, paleomagnetic and carbon isotopic investigations have provided new evidence supporting placement of the Chinese terrestrial Paleocene-Eocene boundary at the base of the Lingcha Formation in the Hengyang Basin, Hunan Province, and within the upper part of the Nomogen Formation in the Erlian Basin, Inner Mongolia. Based on mammalian and ostracod biostratigraphic data, the boundary can also be roughly correlated with the contacts between the Baoyue and Huayong formations in the Sanshui Basin of Guangdong, the Qingjiang and Xinyu formations of Jiangxi, the Fourth Formation of the Funing Group and the Dainan Formation in northern Jiangsu, and the Dabu and Shisanjianfang formations in the Turfan Basin of Xinjiang.

关键词： Vertebrate/ostracod biostratigraphy Paleocene-Eocene boundary correlation Hunan Province Inner Mongolia China

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Early Cretaceous uplift history of the Dabie orogenic belt: Evidence from pluton emplacement depths

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Science China Earth Sciences 2014年第5期57卷 1129-1140页

作者： wang yongsheng wang HaiFeng SHENG Yong XIANG BiWei School of Resource and Environmental Engineering Hefei University of Technology Faculty of Earth Sciences China University of Geosciences

The North Dabie complex unit （NDC） is a widely exposed petro-tectonic unit. To understand post-orogenic uplift history and mechanism of the Dabie orogenic belt, many samples of granite, granodiorite, diorite, and alkali feldspar granite with precise zircon U-Pb ages were collected for electron microprobe analysis of hornblende. Emplacement pressure values were then cal- culated by using an Al-in-hornblende geobarometer. The result shows that total A1 （A1T） values in hornblende range from 1.17 to 1.97 p.f.u., XFe（=Fe/（Fe＋Mg）） from 0.4 to 0.65, and corresponding pressure values from 256.8 to 676.2 MPa for A1T greater than 1.17. It is suggested that although the main mechanism for the uplift is tectonic extension, inhomogeneous uplift related to the pluton emplacement is also important during post-orogenic evolution of the Dabie orogenic belt. Emplacement depth dis- tribution of the plutons shows that uplift in the NDC is affected by horst-graben structures since 120 Ma.

关键词： Dabie orogenic belt North Dabie complex belt Early Cretaceous plutons Al-in-hornblende geobarometer

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