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高能物理与核物理 1998年第3期22卷 265-270页

作者：叶巍沈文庆陆中道冯军马余刚王建松 k.yuasa-Nakagawa T.Nakagawa 中国科学院上海原子核研究所中国原子能科学研究院

用推广的裂变扩散模型研究了角动量对１０．６ＭｅＶ／ｕ８４Ｋｒ（２７Ａｌ，二体裂变）反应断点前粒子多重性的影响，发现阶点前粒子多重性和断点时间随着角动量的减小逐渐增大，而且绝大多数粒子是在鞍点前发射的。对实验中二体裂变... 详细信息

用推广的裂变扩散模型研究了角动量对１０．６ＭｅＶ／ｕ８４Ｋｒ（２７Ａｌ，二体裂变）反应断点前粒子多重性的影响，发现阶点前粒子多重性和断点时间随着角动量的减小逐渐增大，而且绝大多数粒子是在鞍点前发射的。对实验中二体裂变反应发生的角动量范围进行权重平均，得到了与实验一致的断点前粒子多重性。同时还研究了影响断点前粒子多重性和断点时间的诸多因素。

关键词：裂变扩散模型粒子多重性断点角动量氪84 铝

10.6MeV/u^(84)kr+^(27)Al碰撞中粒子发射的方位角分布和方位角关联

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高能物理与核物理 1997年第1期21卷 1-7页

作者：叶巍沈文庆马余刚冯军 T.Nakagawa k.yuasa-Nakagawa k.Furutaka k.Matsuda Y.Futami k.Yoshida J.kasagi S.M.Lee 中国科学院上海原子核研究所上海201800 The Institute of Physical and Chemical Research RIKENWakoSaitama 351-01Japan Department of Physics Tokyo Institute of TechnologyMeguroToyko 152Japan Institute of Physics University of TsukubaTsukubaIbaraki 305Japan Laboratory of Nuclear Science Tohoku UniversitySendaiMiyagi 982Japan

研究了10.6MeV/u^(84)kr+^(27)Al 反应中与碎片符合的轻带电粒子发射,重点研究了用二阶傅里叶级数拟合发射粒子的方位角分布和方位角关联得出的二阶各向异性系数的性质.结果证实了一个事件中的粒子都以相同方位角分布统计独立发射.发现... 详细信息

研究了10.6MeV/u^(84)kr+^(27)Al 反应中与碎片符合的轻带电粒子发射,重点研究了用二阶傅里叶级数拟合发射粒子的方位角分布和方位角关联得出的二阶各向异性系数的性质.结果证实了一个事件中的粒子都以相同方位角分布统计独立发射.发现二阶各向异性系数同碎片的质量用微弱的依赖性,并随发射粒子质量的增加而增加.

关键词：方位角分布统计独立发射重离子反应离子碰撞

POWER DOPPLER ULTRASONOGRAPHY OF CERVICAL LYMPHADENOPATHY IN HEAD AND NECk CANCER

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POWER DOPPLER ULTRASONOGRAPHY OF CERVICAL LYMPHADENOPATHY IN...

Aqueous-phase reforming of hydroxyacetone solution to bio-based H_(2)over supported Pt catalysts

第二届中国国际暨第五届全国口腔颌面外科学术会议

作者： k.yuasa T.NAkANO W．kAGE T.kAWAZU M.SAITO E.NAkAYAMA k.MIWA S.kANDA S.OZEkI T.NAGATA M.SHINOHARA T.IkEBE DEPT.OF ORAL AND MAXILLOFACIAL RADIOLOGY FACULTY OF DENTISTRY kYUSHU UNIVERSITY FUkUOkA JAPAN DEPT.OF ORAL AND MAXILLOFACIAL RADIOLOGY FACULTY OF DENTISTRY kYUSHU UNIVERSITY FUkUOkA JAPAN FIRST DEPT.OF ORAL AND MAXILLOFACIAL SURGERY FACULTY OF DENTISTRY kYUSHU UNIVERSITY FUkUOkA JAPAN IDEPT.OF ORAL AND MAXILLOFACIAL RADIOLOGY FACULTY OF DENTISTRY kYUSHU UNIVERSITY FUkUOkA JAPAN IDEPT.OF ORAL AND MAXILLOFACIAL RADIOLOGY FACULTY OF DENTISTRY kYUSHU UNIVERSITY FUkUOkA JAPAN IDEPT.OF ORAL AND MAXILLOFACIAL RADIOLOGY FACULTY OF DENTISTRY kYUSHU UNIVERSITY FUkUOkA JAPAN IDEPT.OF ORAL AND MAXILLOFACIAL RADIOLOGY FACULTY OF DENTISTRY kYUSHU UNIVERSITY FUkUOkA JAPAN IDEPT.OF ORAL AND MAXILLOFACIAL RADIOLOGY FACULTY OF DENTISTRY kYUSHU UNIVERSITY FUkUOkA JAPAN FIRST DEPT.OF ORAL AND MAXILLOFACIAL SURGERY FACULTY OF DENTISTRY kYUSHU UNIVERSITY FUkUOkA JAPAN FIRST DEPT.OF ORAL AND MAXILLOFACIAL SURGERY FACULTY OF DENTISTRY kYUSHU UNIVERSITY FUkUOkA JAPAN SECOND DEPT.OF ORAL AND MAXILLOFACIAL SURGERY FACULTY OF DENTISTRY kYUSHU UNIVERSITY FUkUOkA JAPAN SECOND DEPT.OF ORAL AND MAXILLOFACIAL SURGERY FACULTY OF DENTISTRY kYUSHU UNIVERSITY FUkUOkA JAPAN

OBJECTIVE:The aims of this study were to evaluate the usefulness of power Doppler ultrasonography for diagnosing cervical lymphadenopathy and to determine the criteria for differentiating cervical lymph node metastasis from non- *** AND METHODS:During April 1997 and April 1998,187 lymph nodes in 36 patients with head and neck cancer were retrospectively evaluated with power Doppler *** patients were pathologically

关键词： Doppler POWER DOPPLER ULTRASONOGRAPHY OF CERVICAL LYMPHADENOPATHY IN HEAD AND NECk CANCER

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Green Energy & Environment 2024年第4期9卷 777-788页

作者： A.k.k.Vikla k.koichumanova Songbo He k.Seshan Joint International Research Laboratory of Circular Carbon Nanjing Tech UniversityNanjing211816China Faculty of Science and Technology University of Twente7500 AE EnschedeThe Netherlands CoRe Pro 9723 BL GroningenThe Netherlands

Aqueous-phase reforming(APR)is an attractive process to produce bio-based hydrogen from waste biomass streams,during which the catalyst stability is often challenged due to the harsh reaction *** this work,three Pt-based catalysts supported on C,AlO(OH),and ZrO_(2)were investigated for the APR of hydroxyacetone solution in afixed bed reactor at 225℃and 35 *** them,the Pt/C catalyst showed the highest turnover frequency for H_(2)production(TOF of 8.9 molH_(2)molPt^(-1)min^(-1))and the longest catalyst *** the AlO(OH)and ZrO_(2)supported Pt catalysts,the side reactions consuming H_(2),formation of coke,and Pt sintering result in a low H_(2)production and the fast catalyst *** proposed reaction pathways suggest that a promising APR catalyst should reform all oxygenates in the aqueous phase,minimize the hydrogenation of the oxygenates,maximize the WGS reaction,and inhibit the condensation and coking reactions for maximizing the hydrogen yield and a stable catalytic performance.

关键词： APR Hydroxyacetone TOF Bio-based H_(2) Support effect

Direct scaling of residual displacements for bilinear and pinching oscillators

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 129-149页

作者： Mohammad Saifullah Vinay k.Gupta Department of Civil Engineering Indian Institute of Technology KanpurKanpur 208016India

The estimation of residual displacements in a structure due to an anticipated earthquake event has increasingly become an important component of performance-based earthquake engineering because controlling these displacements plays an important role in ensuring cost-feasible or cost-effective repairs in a damaged structure after the *** attempt is made in this study to obtain statistical estimates of constant-ductility residual displacement spectra for bilinear and pinching oscillators with 5%initial damping,directly in terms of easily available seismological,site,and model *** of the available models for the bilinear and pinching oscillators are useful when design spectra for a seismic hazard at a site are not *** statistical estimates of a residual displacement spectrum are proposed in terms of earthquake magnitude,epicentral distance,site geology parameter,and three model parameters for a given set of ductility demand and a hysteretic energy capacity coefficient in the case of bilinear and pinching models,as well as for a given set of pinching parameters for displacement and strength at the breakpoint in the case of pinching model *** proposed scaling model is applicable to horizontal ground motions in the western *** earthquake magnitudes less than 7 or epicentral distances greater than 20 km.

关键词： residual displacement spectrum bilinear hysteresis model pinching hysteresis model nonlinear analysis scaling model

Analysis of the Oscillatory Flows of Multiple Shock Waves in a Constant Area Duct

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Journal of Thermal Science 2024年第3期33卷 794-806页

作者： k JAMES Jintu kIM Heuy Dong Department of Mechanical Engineering Andong National UniversityAndong36729Republic of Korea CAD-IT korea Co. Ltd.Seoul08591Republic of Korea

The oscillatory response of multiple shock waves to downstream perturbations in a supersonic flow is studied numerically in a rectangular *** shock waves are formed inside the duct at a shock Mach number of *** duct has an exit height of H,and the effect of duct resonance on multiple shock oscillations is investigated by attaching exit ducts of lengths 0H,50H,and *** downstream disturbance frequency varied from 10 Hz to 200 Hz to explore the oscillation characteristics of the multiple shock *** oscillatory response of shock waves under self-excited and forced oscillation conditions are analyzed in terms of wall static pressure,shock train leading-edge location,shock train length,and the size of the separation *** extent of the initial shock location increases with an increase in exit duct length for the self-excited oscillation *** analysis of the shock train leading edge and the spectral analysis of wall static pressure variations are *** variation in the shock train length is analyzed using the pressure ratio method for self-excited as well as forced *** RMS amplitude of the normalized shock train length(ζ_(ST))increases with an increase in the exit duct length for the self-excited oscillation *** the downstream perturbation frequency is increased,ζ_(ST)is decreased for exit duct *** all exit duct designs and downstream forcing frequencies,the size of the separation bubble grows and shrinks during the shock oscillations,demonstrating the dependence on duct resonance and forced oscillations.

关键词： shock train downstream disturbance supersonic flow shock wave boundary layer interaction duct resonance flow separation

Impact of Fin Arrangement on Heat Transfer and Melting Characteristics of Phase Change Material

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Journal of Thermal Science 2024年第2期33卷 435-456页

作者： Arun UNIYAL Yogesh k.PRAJAPATI Department of Mechanical Engineering National Institute of Technology UttarakhandSrinagar(Garhwal)246174India Department of Mechanical Engineering BIT SindriDhanbadJharkhand828123India

Present work investigates the heat transfer and melting behaviour of phase change material(PCM) in six enclosures(enclosure-1 to 6) filled with paraffin *** enclosures are equipped with distinct arrangements of the fins while keeping the fin's surface area equal in each *** analysis has been presented to recognize the suitable fin arrangements that facilitate improved heat transfer and melting rate of the *** wall of the enclosure is maintained isothermal for the temperature values 335 k,350 k and 365 *** length of the enclosure including fins is ranging between 0 and *** have been illustrated through the estimation of important performance parameters such as energy absorbing capacity,melting rate,enhancement ratio,and Nusselt *** has been found that melting time(to melt 100% of the PCM) is 60.5%less in enclosure-2(with two fins of equal length) as compared to the enclosure-1,having no *** the fin surface area equal,if the longer fin is placed below the shorter fin(enclosure-3),melting time is further decreased by 14.1% as compared to ***,among all the configurations,enclosure-6 with wire-mesh fin structure exhibits minimum melting time which is 68.4% less as compared to the *** on the findings,it may be concluded that fins are the main driving agent in the enclosure to transfer the heat from heated wall to the *** design and positioning of the fins improve the heat transfer rate followed by melting of the PCM in the entire area of the *** of the favourable vortices and natural convection current in the enclosure accelerate the melting phenomenon and help to reduce charging time.

关键词： phase change material enclosure fin melting fraction energy storage heat transfer

MDCN:Modified Dense Convolution Network Based Disease Classification in Mango Leaves

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Computers, Materials & Continua 2024年第2期78卷 2511-2533页

作者： Chirag Chandrashekar k.P.Vijayakumar k.Pradeep A.Balasundaram School of Computer Science and Engineering Vellore Institute of Technology(VIT)ChennaiIndia Center for Cyber Physical Systems School of Computer Science and EngineeringVellore Institute of Technology(VIT)ChennaiIndia

The most widely farmed fruit in the world is *** the production and quality of the mangoes are hampered by many *** diseases need to be effectively controlled and ***,a quick and accurate diagnosis of the disorders is *** convolutional neural networks,renowned for their independence in feature extraction,have established their value in numerous detection and classification ***,it requires large training datasets and several parameters that need careful *** proposed Modified Dense Convolutional Network(MDCN)provides a successful classification scheme for plant diseases affecting mango *** model employs the strength of pre-trained networks and modifies them for the particular context of mango leaf diseases by incorporating transfer learning *** data loader also builds mini-batches for training the models to reduce training ***,optimization approaches help increase the overall model’s efficiency and lower computing *** employed on the MangoLeafBD Dataset consists of a total of 4,000 *** the experimental results,the proposed system is compared with existing techniques and it is clear that the proposed algorithm surpasses the existing algorithms by achieving high performance and overall throughput.

关键词： Leaf disease detection deep convolutional neural networks transfer learning optimization MangoLeafBD Dataset

Long Term X-Ray Spectral Variations of the Seyfert-1 Galaxy Mrk 279

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Research in Astronomy and Astrophysics 2024年第6期24卷 307-314页

作者： k.Akhila Ranjeev Misra Savithri H.Ezhikode k.Jeena Department of Physics Providence Women’s CollegeUniversity of CalicutKerala 673009India Inter-University Centre for Astronomy and Astrophysics(IUCAA) PB No.4GaneshkhindPune 411007India Department of Physics and Electronics CHRIST(Deemed to be University)Hosur Main RoadBangalore 560029India

We present the results from a long term X-ray analysis of Mrk 279 during the period 2018–*** use data from multiple missions–AstroSat,NuSTAR and XMM-Newton,for the *** X-ray spectrum can be modeled as a double Comptonization along with the presence of neutral Fe kαline emission,at all *** determined the source’s X-ray flux and luminosity at these different *** find significant variations in the source’s flux *** also investigate the variations in the source’s spectral components during the observation *** find that the photon index and hence the spectral shape follow the variations only over longer time *** probe the correlations between fluxes of different bands and their photon indices,and found no significant correlations between the parameters.

关键词： galaxies:Seyfert galaxies:individual(Mrk 335) X-rays:galaxies