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Plant Phenomics 2024年第2期6卷 401-415页

作者： Xun Zhao Jianbo Qi Zhexiu Yu Lijuan Yuan Huaguo Huang Key Laboratory for Silviculture and Conservation of Ministry of Education Beijing Forestry UniversityBeijing 100083China Innovation Research Center of Satellite Application Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China

Quantifying the relationship between light and stands or individual trees is of great significance in understanding tree competition,improving forest productivity,and comprehending ecological ***,accurately depicting the spatiotemporal variability of light under complex forest structural conditions poses a challenge,especially for precise forest management decisions that require a quantitative study of the relationship between fine-scale individual tree structure and light.3D RTMs(3-dimensional radiative transfer models),which accurately characterize the interaction between solar radiation and detailed forest scenes,provide a reliable means for depicting such relationships.

关键词： quantification lidar active modeling apar data call with absorbed fine-scale

Government Subsidies and Enterprise Innovation:Moderation Effect of absorbed Slack

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Journal of Finance Research 2019年第1期3卷 78-85页

作者： Ren Na Wen Cheng School of Economics Hefei University of TechnologyHefeiAnhui230601China

It is worth studying whether enterprises receiving government subsidies can transform them into innovative achievements under the constraints of enterprise *** data from the three industries of electronics,pharmaceuticals,and information technology during 2013-2016 were empirical tested to verify the moderating effect of the absorbed slack on the relationship between government subsidies and enterprise *** results show that government subsidies can promote enterprise innovation;absorbed slack promotes enterprise innovation;the absorbed slack of enterprises plays a positive moderation role in the relationship between government subsidy and enterprise *** other words,the enterprises with high absorbed slack can promote the innovation of enterprises by government *** conclusions provide theoretical guidance for government departments to select the most suitable enterprises which accept innovative subsidies.

关键词： Government subsidies Enterprise innovation absorbed slack

Ensuring Uniformity of Measurements of absorbed Doses of Intensive Photon and Electron Radiation in Radiation Technologies

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Journal of Applied Mathematics and Physics 2015年第8期3卷 942-946页

作者： V. V. Generalova A. A. Gromov O. I. Kovalenko Research Department of Metrology of Ionizing Radiation Russian Metrological Institute of Technical Physics and Radio Ingineering (VNIIFTRI) Mendeleevo Moscow Region Russia

Ensuring reliability and traceability of the unit of absorbed dose of intense photon and electron radiation, used in radiation technologies in industry, is based on the creation of a system of sample measures and methods of transmission with minimal loss of dimensional accuracy of the unit of absorbed dose from the sample tools to working dosimeters and is a necessary basis of yield growth, of increase of labour productivity and the introduction of innovative products. The measuring capabilities of the State primary special standard of power unit of absorbed dose of intensity photon, electron and beta radiation for radiation technologies and of the standards of the absorbed dose of photon and electron radiation, used for radiation monitoring of radiation pro- cesses.

关键词： Radiation Technology absorbed Dose Ensuring Uniformity of Measurements Certified Reference Material

Measurement and Monte Carlo simulation of γ-ray dose rate in high-exposure building materials

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Nuclear Science and Techniques 2017年第2期28卷 30-34页

作者： A. Abbasi M. Hassanzadeh Reactor Research School Nuclear Science and Technology Institute (NSTRI) P.O. Box 141551339 Tehran Iran University of Kyrenia Kyrenia North Cyprus Mersin 10Turkey

Natural radioactivity radionuclides in building materials, such as^(226)Ra,^(232)Th and^(40)K, cause indoor exposure due to their gamma-rays. In this research, in a standard dwelling room(5.0 m 9 4.0 m 9 2.8 m), with the floor covered by various granite stones, was set up to simulate the dose rates from the radionuclides using MCNP4 C code. Using samples of granite building products in Iran, activities of the^(226)Ra,^(232)Th and^(40)K were measured at 3.8–94.2, 6.5–172.2 and 556.9–1529.2 Bq kg^(-1),respectively. The simulated dose rates were26.31–184.36 n Gy h^(-1), while the measured dose rates were 27.70–204.17 n Gy h^(-1). With the results in good agreement, the simulation is suitable for any kind of dwelling places.

关键词： Radioactivity Building materials absorbed dose Experimental MCNP4C

Numerical examination of wave power absorption by the Edinburgh Duck wave energy converter device

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Journal of Hydrodynamics 2021年第2期33卷 323-333页

作者： Shu Li Bin Teng State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China

A two-dimensional computational fluid dynamics(CFD)numerical model is developed to study the power takeoff(PTO)efficiency of an Edinburgh duck wave energy converter(WEC)device by using the OpenFOAM source *** the numerical validations and the convergent verifications,the characteristics of the duck WEC device for the power takeoff in various incident wave periods are *** present numerical investigation indicates that the maximum absorbed power of the duck WEC device is attained in its resonant period,while the maximum efficiency is achieved in a lower *** influence of the damping coefficient on the PTO is also *** optimal damping coefficient for acquiring more power and better efficiency is determined from a numerical examination.

关键词： Edinburgh Duck wave energy converter(WEC)device absorbed power efficiency computational fluid dynamics(CFD)model OpenFOAM

Variation in patient dose due to differences in calibration and dosimetry protocols

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Nuclear Science and Techniques 2018年第5期29卷 44-49页

作者： Wazir Muhammad Asad Ullah Gulzar Khan Tahir Zeb Khan Tauseef Jamaal Fawad Ullah Matiullah Khan Amjad Hussain Department of Therapeutic Radiology Yale-School of MedicineYale UniversityNew HavenCT 06520-8040USA Heath Physics Division(HPD) Pakistan Institute of Nuclear Science and Technology(PINSTECH)Islamabad 45650Pakistan Department of Physics Abul Wali Khan UniversityMardan 23200Pakistan Pakistan Institute Nuclear Science&Technology(PIEAS) Islamabad 45650Pakistan Department of Physics Kohat University of Science and TechnologyKohat 26000Pakistan Department of Medical Physics CancerCare ManitobaBrandonMB R7A 2B3Canada

For precise and accurate patient dose delivery,the dosimetry system must be calibrated properly according to the recommendations of standard dosimetry protocols such as TG-51 and TRS-398. However, the dosimetry protocol followed by a calibration laboratory is usually different from the protocols that are followed by different clinics, which may result in variations in the patient *** prime objective in this study was to investigate the effect of the two protocols on dosimetry *** measurements were performed for a Co-60 teletherapy unit and a high-energy Varian linear accelerator with 6 and 15 MV photon and 6, 9, 12, and 15 MeV electron beams, following the recommendations and procedures of the AAPM TG-51 and IAEA TRS-398 dosimetry protocols. The dosimetry systems used for this study were calibrated in a Co-60 radiation beam at the Secondary Standard Dosimetry Laboratory(SSDL) PINSTECH,Pakistan, following the IAEA TRS-398 protocol. The ratio of the measured absorbed doses to water in clinical setting,D_w(TG-51/TRS-398), was 0.999 and 0.997 for 6 and15 MV photon beams,whereas these ratios were 1.013,1.009, 1.003, and 1.000 for 6, 9, 12, and 15 MeV electron beams, respectively. This difference in the absorbed dosesto-water D_w ratio may be attributed mainly due to beam quality(K_Q) and ion recombination correction factor.

关键词： Radiation dosimetry Dosimetry systems calibrations Patient dose absorbed dose-to-water ratio AAPM TG-51 IAEA TRS-398

Heterogeneous reaction of NO_2 with sea salt particles

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Science China Chemistry 2010年第12期53卷 2652-2656页

作者： YE ChunXiang 1,LI HongJun 1,ZHU Tong 1,SHANG Jing 1,ZHANG ZeFeng 1,2 & ZHAO DeFeng 1 1 State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering,Peking University,Beijing 100871,China 2 College of Atmospheric Physics,Nanjing University of Information Science and Technology,Nanjing 210044,China 1. State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University Beijing 100871 China2. College of Atmospheric Physics Nanjing University of Information Science and Technology Nanjing 210044 China

To understand how NO2 reacts with sea salt particles in the atmosphere of Mega-cities in coastal zones,the heterogeneous reaction of NO2 on the surface of wet sea salt was investigated with diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and ion chromatography (IC).Kinetic measurements indicated that nitrate formation on sea salt was second order in NO 2 concentration and reactive uptake coefficients were (5.51 ± 0.19) × 10-7 and 1.26 × 10-6 respectively under 0% and 20% relative humidity (RH) at NO 2 molecular concentration of 1.96 × 1015 mol/*** results showed that liquid water was formed at the site of MgCl2·6H2O,CaCl2·2H2O on the surface of sea salt and made the reaction more sustainable by releasing hydrated water and absorbing water from air even under a low RH (30%).Therefore,pure NaCl particles should not be used to represent sea salt in studies of the heterogeneous reaction with NO2.

关键词： sea salt particles diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) hydrated water absorbed water reactive uptake coefficient

NATURAL BACKGROUND RADIOACTIVITY LEVELS IN THE TERRESTRIAL ENVIRONMENT OF HONG KONG

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Nuclear Science and Techniques 1993年第3期4卷 151-157页

作者：关祖杰余君岳杨健明 M.J.Stokes Zhongshan University Guangzhou 5100275 City Polytechnic of Hong Kong

This paper analyses and summarizes the natural radionuclide contents of soil and building materials, radon concentrations and the penetrating radiation levels in Hong Kong. From these, a thorough and objective assessment for the terrestrial background irradiation level of Hong Kong was made. Finally, the annual effective dose equivalent received by Hong Kong people due to the natural background irradiation was calculated to be 3.2 mSv.

关键词： Natural radioactivity absorbed gamma dose rate Indoor radon Soil and building materials Background levels Effective dose equivalent

CADMIUM FLUX AND GENOTOXICITY IN AN EXPERIMENTAL MARINE FOOD CHAIN

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Chinese Journal of Oceanology and Limnology 1991年第4期9卷 291-299页

作者：林光恒秦松曾呈奎 Institute of Oceanology Academia Sinica Qingdao 266071

Cadmium flux through a lab food chain (Phaeodactylum tricornutum Bohlin- Penaeus orientate Kishinouye- Hexagrammos otakii Jordan et Starks) and its genotoxicity were investigated. The results are as follows:1. High doses of cadmium (>0.003 mol / L) induced flocculation and quick precipitation of Phaeodactylum tricornutum; lower doses of cadmium could be adsorbed on and absorbed by P. tricornutum without delaying its growth. Cadmium concentrations in algae increased with dosage, and cadmium ions removed from the medium were in proportion to dosage. In vivo chelation and organizable combination of absorbed cadmium ions by metabolites of P. tricornutum can be considered as bio-detoxification.2. Cadmium concentration decreased in the transfers from P. tricornutum to P. orientalis and from the latter to H. otakii. Transfer coefficient of cadmium in the first flux was 66.6% and 29.9% in the second. Results of t tests showed that mutagenicity of ashed internal organs of experimental prawns was significantly

关键词： dosage cadmium removed absorbed adsorbed organs proportion latter algae dissolved

Multipole source-configuration of active sound absorption(ASA)in space sound field

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Chinese Journal of Acoustics 1990年第3期9卷 212-220页

作者： LU Guangqing(Institute of Acoustics , Academia Sinica )Institute of Machanical Engineering.Xian Jiaotong University

In this paper, the energy formulas of Active Sound Absorption (ASA) in space sound field have been derived from the basic sound wave equation , and ASA including the relevant conditions of multipole secon -dary-source , such as monopole , dipole and tripole , etc., has been discussed . On the basis of the discussion, it has pointed out that dipole secondary-configuration (DAA) is the simplest attenuator. The results of the experiments done in anechoic chamber have shown that DAA has effective performances which just provide the fundation and feasibility of practical use .

关键词： dipole Absorption chamber formulas discussion directional downstream realization absorbed attenuation