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Investigation of the level spectra of nuclei in the northeast region of doubly magic^(40)Ca with intruder orbit g_(9/2) 被引量:1
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作者 Jin-Zhong Han Shuai Xu +1 位作者 Amir Jalili Han-Kui Wang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第6期115-123,共9页
This study utilizes large-scale shell model calculations with the extended pairing and multipole–multipole force model(EPQQM)to investigate low-lying states in the nuclei of^(42)Ca,^(42)Sc,and^(42−44)Ti.The model spa... This study utilizes large-scale shell model calculations with the extended pairing and multipole–multipole force model(EPQQM)to investigate low-lying states in the nuclei of^(42)Ca,^(42)Sc,and^(42−44)Ti.The model space in this study includes the fp shell as well as the intruder g_(9/2)orbit,which accurately reproduces the positive parity levels observed in the aforementioned nuclei and predicts high energy states with negative parity coupled with the intruder g_(9/2).The study further predicts two different configurations in^(43)Ti at around 6 MeV,specificallyπf_(7/2)^(2)νg_(9/2)andπf_(7/2)g_(9/2)νf_(7/2),both of which involve the intruder orbit g_(9/2).The levels coupled with the intruder g_(9/2)in^(44)Ti are predicted to lie between 7 and 11 MeV.The inclusion of the intruder orbit g_(9/2)is crucial for the exploration of high energy states in the northeast region of the doubly magic nucleus^(40)Ca. 展开更多
关键词 Shell model Doubly magic level structure
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Food web structure and trophic levels in a saltwater pond sea cucumber and prawn polyculture system 被引量:3
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作者 GUO Kai ZHAO Wen +2 位作者 WANG Shan LIU Baozhan ZHANG Peng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第4期58-62,共5页
The food sources of aquacultured Apostichopus japonicus and the trophic levels of organisms in a sea cucumber(A. japonicus) and prawn(Penaeus japonica) polyculture system in a saltwater pond in Zhuanghe, Liaoning ... The food sources of aquacultured Apostichopus japonicus and the trophic levels of organisms in a sea cucumber(A. japonicus) and prawn(Penaeus japonica) polyculture system in a saltwater pond in Zhuanghe, Liaoning Province were examined using carbon and nitrogen stable isotopes. Across organisms, δ13C ranged from(–25.47±0.20)‰ to(–16.48±0.17)‰(mean±SD), and δ15N ranged from(4.23±0.49)‰ to(12.44±0.09)‰. The δ13C and δ15N contents of A. japonicus, P. japonica and Fenneropenaeus chinensis were comparatively higher than those of other organisms. Values of δ13C and δ15N revealed that P. japonica, Hemigrapsus sanguineus and Neomysis japonica comprised the largest component of the diet of A. japonicus. The mean trophic level of the organisms in this saltwater pond polyculture system was(2.75±0.08). P. japonica, A. japonicus, F. chinensis,Synechogobius hasta and Neomysis japonica were in the 3rd trophic level(2–3); jellyfish, H. sanguineus and zooplankton were in the 2nd trophic level(1–2); and Enteromorpha prolifera, benthic microalgae, periphyton and suspended matter primarily consisting of phytoplankton, bacteria and humus were in the primary trophic level(0–1). 展开更多
关键词 Aposticbopus japonicas Penaeus japonica stable isotopes food web structure diet composition trophic level
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Real-time estimation of the structural utilization level of segmental tunnel lining
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作者 Nicola Gottardi Steffen Freitag Gunther Meschke 《Underground Space》 SCIE EI 2024年第4期132-145,共14页
Over the last decades,an expansion of the underground network has been taking place to cope with the increasing amount of moving people and freight.As a consequence,it is of vital importance to guarantee the full func... Over the last decades,an expansion of the underground network has been taking place to cope with the increasing amount of moving people and freight.As a consequence,it is of vital importance to guarantee the full functionality of the tunnel network by means of preventive maintenance and the monitoring of the tunnel lining state over time.A new method has been developed for the real-time prediction of the utilization level in tunnel segmental linings based on input monitoring data.The new concept is founded on a framework,which encompasses an offline and an online stage.In the former,the generation of feedforward neural networks is accomplished by employing synthetically produced data.Finite element simulations of the lining structure are conducted to analyze the structural response under multiple loading conditions.The scenarios are generated by assuming ranges of variation of the model input parameters to account for the uncertainty due to the not fully determined in situ conditions.Input and target quantities are identified to better assess the structural utilization of the lining.The latter phase consists in the application of the methodological framework on input monitored data,which allows for a real-time prediction of the physical quantities deployed for the estimation of the lining utilization.The approach is validated on a full-scale test of segmental lining,where the predicted quantities are compared with the actual measurements.Finally,it is investigated the influence of artificial noise added to the training data on the overall prediction performances and the benefits along with the limits of the concept are set out. 展开更多
关键词 Segmental lining Artificial neural networks structural utilization level Real-time prediction structural health monitoring Monitoring data
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Selection and Justification of a New Initial Level of the Material World 被引量:2
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作者 Valentyn Nastasenko 《Journal of Applied Mathematics and Physics》 2021年第5期1089-1099,共11页
The work refers to the foundations of the material world, in particular—to the field of quantum physics associated with the initial level—his fundamental physical constants and elementary particles. The study of the... The work refers to the foundations of the material world, in particular—to the field of quantum physics associated with the initial level—his fundamental physical constants and elementary particles. The study of the initial levels of structuring of this formation is necessary for a better understanding of the foundations of the structure Universe. Therefore, the solution of these problems is an urgent and important task, to which the works of many scientists of the world are devoted, from ancient times to the present. However, these tasks have not yet been fully resolved. Their solution is the main goal and scientific novelty of the work performed. For this, <strong>research methods</strong> were used based on the general principles of deduction and movement from simple initial systems to more complex ones, which are substantiated by reliable physical laws. <strong>The research results</strong> are the choice and substantiation of the initial (zero) level of the material world and a system of fundamental physical constants and physical quantities found on their basis, which precede the 1st level—elementary particles. The problems of determining the wave parameters of the gravitational field and the unified of gravitational and electromagnetic fields of the Universe were solved only as a result of the transition to the zero level of the material world. 展开更多
关键词 levels of Structuring of the Material World Fundamental Physics Constants and Elementary Particles
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Optical Properties, Electronic Energy Level Structure and Electroluminescent Characteristics of Salicylaldehyde Anil Zinc
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作者 Yuying HAO Bingshe XU +3 位作者 Zhixiang GAO Hua WANG Hefeng ZHOU Xuguang LIU 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2006年第2期225-229,共5页
A new electroluminescent material, salicylaldehyde anil zinc (SAZ) was synthesized, which can form high quality, thermal stability, nano-scale amorphous films by vacuum evaporation. Its structure, thermal stability ... A new electroluminescent material, salicylaldehyde anil zinc (SAZ) was synthesized, which can form high quality, thermal stability, nano-scale amorphous films by vacuum evaporation. Its structure, thermal stability were characterized by infrared (IR) spectra, differential thermal analysis-thermogravimetry (DTA-TG) analysis, respectively. The optical properties of SAZ were investigated by UV absorption spectra, Photoluminescence (PL) excitation and emission spectra. The highest occupied molecular orbits (HOMO), lowest unoccupied molecular orbits (LUMO) and optical band gap were evaluated by cyclic voltammetry curve and optical absorption band edge. The electroluminescent devices using SAZ as the emissive layer emit green light with a peak wavelength at 509 nm and a brightness of about 3.1 cd/m^2. 展开更多
关键词 Salicylaldehyde anil zinc Optical properties Electronic energy level structure ELECTROLUMINESCENCE
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Coherent Features of Resonance-Mediated Two-Photon Absorption Enhancement by Varying the Energy Level Structure,Laser Spectrum Bandwidth and Central Frequency
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作者 程文静 梁果 +3 位作者 吴萍 贾天卿 孙真荣 张诗按 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第8期41-45,共5页
The femtosecond pulse shaping technique has been shown to be an effective method to control the multi-photon absorption by the light–matter interaction. Previous studies mainly focused on the quantum coherent control... The femtosecond pulse shaping technique has been shown to be an effective method to control the multi-photon absorption by the light–matter interaction. Previous studies mainly focused on the quantum coherent control of the multi-photon absorption by the phase, amplitude and polarization modulation, but the coherent features of the multi-photon absorption depending on the energy level structure, the laser spectrum bandwidth and laser central frequency still lack in-depth systematic research. In this work, we further explore the coherent features of the resonance-mediated two-photon absorption in a rubidium atom by varying the energy level structure, spectrum bandwidth and central frequency of the femtosecond laser field. The theoretical results show that the change of the intermediate state detuning can effectively influence the enhancement of the near-resonant part, which further affects the transform-limited (TL)-normalized final state population maximum. Moreover, as the laser spectrum bandwidth increases, the TL-normalized final state population maximum can be effectively enhanced due to the increase of the enhancement in the near-resonant part, but the TL-normalized final state population maximum is constant by varying the laser central frequency. These studies can provide a clear physical picture for understanding the coherent features of the resonance-mediated two-photon absorption, and can also provide a theoretical guidance for the future applications. 展开更多
关键词 TL Coherent Features of Resonance-Mediated Two-Photon Absorption Enhancement by Varying the Energy level Structure Laser Spectrum Bandwidth and Central Frequency
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Contour tracking using weighted structure tensor based variational level set
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作者 胡宏伟 马波 曹淑娟 《Journal of Beijing Institute of Technology》 EI CAS 2014年第2期218-225,共8页
A novel contour tracking method using weighted structure tensor based variational level set is proposed in this paper.The image is first converted to weighted structure tensor field by extracting apositive definite sy... A novel contour tracking method using weighted structure tensor based variational level set is proposed in this paper.The image is first converted to weighted structure tensor field by extracting apositive definite symmetric covariance matrix for each pixel.Then,a level set method is employed to represent object contour implicitly which separates the image domain into two areas each modeled by tensor field based Gaussian mixture model separately.By solving agradient flow equation of energy functional with respect to the level set,the object contour will converge to its real profile in the newly arrived frame.Experimental results on several video sequences demonstrate the better performance of our method than the other two contour tracking algorithms. 展开更多
关键词 contour tracking weighted structure tensor Gaussian mixture model level set
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External blast load factors for dome structures based on reliability
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作者 Shao-bo Qi Guang-yan Huang +2 位作者 Xu-dong Zhi Feng Fan Richard GJFlay 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第2期170-182,共13页
Dome structures have been used extensively for industrial,residential,and military infrastructure.Therefore,it is necessary to understand the damage risk potential for such structures for blast-resistant design consid... Dome structures have been used extensively for industrial,residential,and military infrastructure.Therefore,it is necessary to understand the damage risk potential for such structures for blast-resistant design considerations.This paper investigates the effect of blast load variability on the design value and the structural dynamic response.Therefore,the sources of uncertainty in the external blast load on dome structures were discussed firstly.Then based on the probabilistic blast load model for the dome,the rationality of a deterministic mass-increase safety method was assessed.It was found that previous deterministic design method cannot provide a consistent and sound assurance factor or reliability index on the entire dome roof.In addition,it was also proved that the assurance-based load method fails to ensure compliance with structural safety design standards on the dome roof when compared with the reliability-based blast method.A sensitivity analysis on the probabilistic blast load was conducted,and the results indicate that stand-off distance and explosive mass both act as dominant sources to influence the mean and variability of blast load.Therefore,based on the Latin hypercube sampling method,a reliability-based external blast load factor technique was proposed.This technique was further used to estimate structural damage levels of a single-layer reticulated dome under different reliability requirements,associated with a low,medium,and high level of protection grades for a specific explosion scenario,and it indicated that this technique can be useful in the building design to achieve a higher structural anti-explosion capacity.This study herein can serve as a reference for the calculation method of designed blast load. 展开更多
关键词 Dome structure Airblast variability Deterministic design Assurance factor Reliability-based blast load factor structural damage levels
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An evaluation of underlying mechanisms for“fishing down marine food webs”
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作者 DING Qi CHEN Xinjun +2 位作者 YU Wei TIAN Siquan CHEN Yong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2016年第8期32-38,共7页
Since the concept of "fishing down marine food webs" was first proposed in 1998, mean trophic level of fisheries landings(MTL) has become one of the most widely used indicators to assess the impacts of fishing on ... Since the concept of "fishing down marine food webs" was first proposed in 1998, mean trophic level of fisheries landings(MTL) has become one of the most widely used indicators to assess the impacts of fishing on the integrity of marine ecosystem and guide the policy development by many management agencies. Recent studies suggest that understanding underlying causes for changes in MTL is vital for an appropriate use of MTL as an indicator of fishery sustainability. Based on the landing data compiled by Food and Agriculture Organization(FAO) and trophic information of relevant species in Fishbase, we evaluated MTL trends in 14 FAO fishing areas and analyzed catches of upper and lower trophic level groups under different trends of MTL and found that both the cases of a recovered MTL trend and a generally increasing MTL trend could be accompanied by decreasing catches of lower trophic level species. Further, community structure and exploitation history should be considered in using MTL after excluding species with trophic levels lower than 3.25 to distinguish "fishingthrough" from "fishing-down". We conclude that MTL used as an indicator to measure fishery sustainability can benefit from a full consideration of both upper and lower trophic level species and masking effects of community structure and exploitation history. 展开更多
关键词 mean trophic level underlying mechanisms community structure and exploitation history fishery landings
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The Image of an Addressee in Translational Discourse: Exemplified by the Texts Translated From Slovenian Language
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作者 Irina Shchukina 《Journal of Literature and Art Studies》 2013年第12期787-798,共12页
Translational discourse requires at least three participants, therefore it is suggested to consider the universal model of the picture of the world, according to which it is much easier for a translator to combine the... Translational discourse requires at least three participants, therefore it is suggested to consider the universal model of the picture of the world, according to which it is much easier for a translator to combine the pictures of the world of an addressee and an author. An addressee is a mental image existing in the mind of an addresser during the creative process. Having defined its parameters, a translator has an opportunity to deliver the thought of an addresser to an addressee as accurately as possible and to select the means of expression that are clear to an addressee. The type of an addressee correlates with "the relation to the new". 展开更多
关键词 cognitive linguistics target text the language picture of the world DISCOURSE addresser addressee the levels of the structure of the language world picture
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Improving performance of Cs_(2)AgBiBr_(6)solar cell through constructing gradient energy level with deep-level hole transport material
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作者 Zi-Yang Xia Wei Zhang +6 位作者 Cheng Chen Hao-Xin Wang Lin-Qin Wang Ya-Wei Miao Xing-Dong Ding Li-Cheng Sun Ming Cheng 《Rare Metals》 SCIE EI CAS CSCD 2023年第9期3004-3012,共9页
The valence band offset between Cs_(2)AgBiBr_(6)and hole transport layer(HTL)is approximately 1.00 e V,which results in high energy loss and is identified as one of the bottle necks of Cs_(2)Ag BiBr_(6)perovskite sola... The valence band offset between Cs_(2)AgBiBr_(6)and hole transport layer(HTL)is approximately 1.00 e V,which results in high energy loss and is identified as one of the bottle necks of Cs_(2)Ag BiBr_(6)perovskite solar cell(PSC)for achieving high power conversion efficiency(PCE).To tackle this problem,we propose the optimization of the energy level alignment by designing and synthesizing novel deep-level hole transport materials(HTMs).The sole introduction of deep-level HTMs successfully reduces the valence band offset between Cs_(2)Ag Bi Br_(6)and HTL,but induces the increased valence band offset at HTL/Au interface,limiting the PCE improvement.To further solve the problem and improve the PCE,the gradient energy level arrangement is constructed by combining the newly developed deep-level HTM 6,6’-(3-((9,9-dimethyl-9H-fluoren-3-yl)(4-methoxyphenyl)amino)thiophene-2,5-diyl)bis(N-(9,9-dimethyl-9H-fluoren-2-yl)-N,9-bis(4-methoxyphenyl)-9H-carbazol-3-amine)(TF)with 2,2’,7,7’-tetrakis(N,N’-dipmethoxyphenylamine)-9,9-spirobifluorene(Spiro-OMeTAD).Through optimization,an impressive PCE of 3.50%with remarkably high open-circuit voltage(V_(oc))and fill factor(FF)is achieved,qualifying it among the best pristine Cs_(2)AgBiBr_(6)PSCs. 展开更多
关键词 All-inorganic Cs_(2)AgBiBr_(6)perovskite Stepped energy level structure Energy loss Moisture resistance
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A New Complete Hierarchical Classification Approach to Kinematic Chains 被引量:1
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作者 Sun Xiaobin Xiao Renbin (Computer Aided Design Center, Huazhong University of Science and Technology, Wuhan 430074, China) Miscillaneous 《Computer Aided Drafting,Design and Manufacturing》 2000年第2期74-88,共15页
Based on structural properties and genetic isomorphism-identification approach, this paper proposes a classification scheme of kinematic structures to categorize the kinematic chains into different families, thus faci... Based on structural properties and genetic isomorphism-identification approach, this paper proposes a classification scheme of kinematic structures to categorize the kinematic chains into different families, thus facilitating the optimum selection of a basic structure of a mechanism. The kinematic chain is represented by a graph at first. The genetic adaptive model for the graph isomorphism identification is developed, which includes the construction of an effective method to decrease the problem's dimensions and applying an evolutionary searching strategy. From the various invariants of the genetic adaptive model, which charaterize the specific features of a kinematic chain or a family of kinematic chains, we obtain a six-step hierarchical classification scheme. This scheme classifies together the kinematic chains having similar sub-sets of structures forming isomorphic sub-chains. An example illustrates the theory, procedure and utitlity of the hierarchical classification. The scheme reduces computing time and effort in the optimum selection of a kinematic structure from a large family of kinematic chains. 展开更多
关键词 kinematic chain isomorphism identification level structure genetic algorithm
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Multi-quasiparticle excitations and the impact of the high-j intruder orbital in the N=51^93 Mo nucleus 被引量:1
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作者 Hao Wang Ke-Yan Ma +3 位作者 Yi-Heng Wu Yi-Feng Lv Hao-Nan Pan Jing-Bin Lu 《Chinese Physics C》 SCIE CAS CSCD 2021年第1期208-214,共7页
The level structures of 93 Mo are investigated using Large Scale Shell Model calculations,and reasonable agreement is obtained between the experimental and calculated values.The calculated results show that the lower-... The level structures of 93 Mo are investigated using Large Scale Shell Model calculations,and reasonable agreement is obtained between the experimental and calculated values.The calculated results show that the lower-lying states are mainly dominated by proton excitations from the If5/2,2 p3/2,and 2 p1/2 orbitals into the higher orbitals across the Z=38 or Z=40 subshell closure.For the higher-spin states,multi-particle excitations,including the excitation of 2 d5/2 neutrons across the N=56 subshell closure into the high-j intruder 1 h11/2 orbital,are essential.Moreover,the previously unknown spin-parity assignments of the six higher excited states in 93 Mo are inferred from the shell model calculations. 展开更多
关键词 level structure shell model multi-particle excitation MO
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Shell-model calculations for the semi-magic nucleus 85Br and systematic features of the N=50 odd-A isotones
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作者 Rui-Ju Guo Zhi-Quan Li +2 位作者 Chen Liu Yong-He Tian Shou-Yu Wang 《Chinese Physics C》 SCIE CAS CSCD 2017年第8期108-111,共4页
Level structures of 85Br have been investigated using the shell-model code nushellx within a large model space containing the neutron-core excitations across the N = 50 closed shell. The calculated results have been c... Level structures of 85Br have been investigated using the shell-model code nushellx within a large model space containing the neutron-core excitations across the N = 50 closed shell. The calculated results have been compared with the available experimental data. Reasonable agreement between the experimental and calculated values is obtained, which indicates that the neutron-core excitations are essential to reproduce the level structures of 85Br. The systematic features of neutron-core excitations in the N = 50 isotones are investigated. 展开更多
关键词 level structure SHELL-MODEL neutron-core excitations
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Multi-guasiparticle excitations of 91Ru
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作者 Yong Zheng Gde France +2 位作者 Xiao-Hong Zhou Shan Huang Min-Liang Liu 《Chinese Physics C》 SCIE CAS CSCD 2020年第2期80-87,共8页
The level structure in neutron-deficient nucleus 91Ru was investigated via the 58Ni(36Ar,2 plnγ)Ru reaction at a beam energy of 111 MeV.Charged particles,neutrons,and y-rays were emitted in this reaction and detected... The level structure in neutron-deficient nucleus 91Ru was investigated via the 58Ni(36Ar,2 plnγ)Ru reaction at a beam energy of 111 MeV.Charged particles,neutrons,and y-rays were emitted in this reaction and detected by the DIAMANT CsI ball,Neutron Wall,and the EXOGAM Ge clover array,respectively.In addition to the previously reported levels in 91Ru,new low-to-medium spin states were observed.Angular correlation and linear polarization measurements were performed to unambiguously determine spins and parities of the excited states in 91 Ru.The low-spin states of 91 Ru exhibit a scheme of multi-quasiparticle excitations,which is very similar to that of the neighboring N=47 isotone.These excitations have been interpreted in terms of the shell model.The calculations performed in the configuration space(p3/2,f5/2,p1/2,g9/2)reproduce the experimental excitation energies reasonably well,supporting the interpretation of the newly assigned positive-parity states in terms of the three quasiparticle configurationsπ(g9/2)^-2v(g9/2^-1 and v(g9/2)^-3. 展开更多
关键词 level structure neutron deficient nucleus low-spin states shell model three quasiparticle configuration
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