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Multi-component decompositions,linear superpositions,and new nonlinear integrable coupled KdV-type systems
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作者 Xiazhi Hao S Y Lou 《Communications in Theoretical Physics》 2025年第2期1-12,共12页
In the realm of nonlinear integrable systems,the presence of decompositions facilitates the establishment of linear superposition solutions and the derivation of novel coupled systems exhibiting nonlinear integrabilit... In the realm of nonlinear integrable systems,the presence of decompositions facilitates the establishment of linear superposition solutions and the derivation of novel coupled systems exhibiting nonlinear integrability.By focusing on single-component decompositions within the potential BKP hierarchy,it has been observed that specific linear superpositions of decomposition solutions remain consistent with the underlying equations.Moreover,through the implementation of multi-component decompositions within the potential BKP hierarchy,successful endeavors have been undertaken to formulate linear superposition solutions and novel coupled Kd V-type systems that resist decoupling via alterations in dependent variables. 展开更多
关键词 integrable system single-component decomposition multi-component decomposition linear superposition integrable coupled KdV-type system
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A facile high-efficiency preparation strategy for Al-containing multi-component boride microcrystals with superior comprehensive performance
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作者 Yong Fan Jinfeng Nie +7 位作者 Zhigang Ding Yujing Zhang Xiang Chen Wei Liu Sen Yang Sida Liu Xiangfa Liu Yonghao Zhao 《Journal of Materials Science & Technology》 2025年第1期190-203,共14页
Multi-component transition group metal borides(MMB_(2))have become a research hotspot due to their new composition design concepts and superior properties compared with conventional ceramics.Most of the current method... Multi-component transition group metal borides(MMB_(2))have become a research hotspot due to their new composition design concepts and superior properties compared with conventional ceramics.Most of the current methods,however,are complicated and time-consuming,the mass production remains a chal-lenge.Herein,we proposed a new high-efficiency strategy for synthesis of MMB_(2)using molten aluminum as the medium for the first time.The prepared Al-containing multi-component borides(TiZrHfNbTa)B_(2)microcrystals had a homogeneous composition with a hexagonal AlB_(2)structure and ultra-high hardness value of∼35.3 GPa,which was much higher than data reported in the literature and the rule of mix-ture estimations.Furthermore,combined with the First-principles calculation results,we found that the Poisson’s ratio(v)values exhibit a clearly ascending trend from 0.17 at VEC=3.5 to 0.18 at VEC=3.4,then to 0.201 at VEC=3.2 with the increasing of Al content.This indicates that the intrinsic toughness of multi-component boride microcrystals is obviously enhanced by the trace-doped Al elements.Besides,the fabricated Al-containing multi-component boride microcrystals have superior oxidation activation en-ergy and structural stability.The enhanced oxidation resistance is mainly attributed to the formation of a protective Al2 O3 oxide layer and the lattice distortion,both of which lead to sluggish diffusion of O_(2).These findings propose a new unexplored avenue for the fabrication of MMB_(2)materials with supe-rior comprehensive performance including ultra-hardness and intrinsically improved thermo-mechanical properties. 展开更多
关键词 multi-component borides First-principles calculations Crystal growth Mechanical properties Oxidation behavior
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Indolent T-cell lymphoma of the gastrointestinal tract coexisting with gastric signet-ring cell carcinoma:A case report and review of literature
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作者 Xue Chen Jia-Qi Bo +7 位作者 Xiao-Xiang Gao Su-Xia Zhang Jie Li Hui Wang Mu-Ye Yang Qian-Qian Guo Bing Xiu Yu Zeng 《World Journal of Gastroenterology》 2025年第47期172-181,共10页
BACKGROUND Indolent T-cell lymphoma of the gastrointestinal tract(iTCL-GI)is a rare mature T-cell lymphoma that has been formally recognized as a distinct entity in the 5th Edition World Health Organization Classifica... BACKGROUND Indolent T-cell lymphoma of the gastrointestinal tract(iTCL-GI)is a rare mature T-cell lymphoma that has been formally recognized as a distinct entity in the 5th Edition World Health Organization Classification of Tumours of Haematolymphoid Tumours.However,the coexistence of iTCL-GI with epithelial malignancies is rare in clinical practice.This study reports a case of iTCL-GI with gastric signet-ring cell carcinoma(SRCC).We aim to increase diagnostic awareness among clinicians and pathologists regarding multiple primary tumors.CASE SUMMARY A 65-year-old female presented with a 5-month history of lower abdominal pain,bloating,and vomiting.An abdominal computed tomography scan revealed irregular thickening of the gastric wall.Endoscopy revealed diffuse mucosal edema and rigid mucosa along the lesser curvature of the gastric body.There was a 1.5 cm mucosal protrusion on the greater curvature.Biopsy revealed that the lamina propria was expanded by a dense,nondestructive infiltrate of small lymphocytes in the greater curvature,which were characterized by a CD3+/CD8+/TIA-1+immunophenotype with a low Ki-67 index.Clonal T-cell receptor rearrangement was detected,but the Epstein-Barr virus encoded RNA's was negative.Lesions on the lesser curvature of the gastric body were confirmed to be SRCCs.After three months of follow-up,the patient completed four cycles of chemotherapy targeting the SRCC.While her abdominal pain improved,she experienced a weight loss of 5 kg.CONCLUSION Clinicians and pathologists must integrate assessment of these rare cases to prevent misdiagnosis and guide clinical practice. 展开更多
关键词 Indolent T-cell lymphoma Gastrointestinal tract Signet-ring cell carcinoma coexistENCE DIAGNOSIS Case report
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Uncovering the hardening mechanism of multi-component carbide ceramics based on the coupling effect of covalent bond enhancement and lattice distortion
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作者 Qingyi Kong Qinchen Liu +7 位作者 Lei Chen Sijia Huo Kunxuan Li Mingxuan Mao WeiWei Sun Yujin Wang Suk-Joong L.Kang Yu Zhou 《Journal of Materials Science & Technology》 2025年第31期102-112,共11页
The hardening mechanism of multi-component carbide ceramic has been investigated in detail through a combination of experiments,first-principles calculations,and ab initio molecular dynamics(AIMD).Eight dense carbide ... The hardening mechanism of multi-component carbide ceramic has been investigated in detail through a combination of experiments,first-principles calculations,and ab initio molecular dynamics(AIMD).Eight dense carbide ceramics were prepared by spark plasma sintering.Compulsorily,all the multi-component carbide samples have similar carbon content,grain size,and uniform compositional distribution by optimizing the sintering process and adjusting the initial raw materials.Hence the interference of other factors on the hardness of multi-component carbide ceramics is minimized.The effects of changes in the elemental species on the lattice distortion,bond strength,bonding properties,and electronic structure of multi-component carbide ceramics were thoroughly analyzed.These results show that the hardening of multi-component carbide ceramic can be attributed to the coupling of solid solution strengthening caused by lattice distortion and covalent bond strengthening.Besides,the“host lattice”of multi-component carbide ceramics is defined based on the concept of supporting lattice.The present work is of great significance for a deeper understanding of the hardening mechanism of multi-component carbide ceramics and the design of superhard multi-component carbides. 展开更多
关键词 multi-component ceramics Mechanical properties Hardening mechanism First principle calculation Ab initio molecular dynamics
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Photocatalytic multi-component synthesis of ester-containing quinoxalin-2(1H)-ones using water as the hydrogen donor
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作者 Qiang Feng Jindong Hao +3 位作者 Ya Hu Rong Fu Wei Wei Dong Yi 《Chinese Chemical Letters》 2025年第6期484-488,共5页
A convenient photocatalytic multi-component reaction of alkenes,quinoxalin-2(1H)-ones,and diazo compounds has been developed in the presence of water.A number of ester-containing quinoxalin-2(1H)-ones could be efficie... A convenient photocatalytic multi-component reaction of alkenes,quinoxalin-2(1H)-ones,and diazo compounds has been developed in the presence of water.A number of ester-containing quinoxalin-2(1H)-ones could be efficiently obtained in moderate to good yields at room temperature.This metal-free visiblelight-driven tandem reaction was conducted through proton-coupled electron transfer(PCET)process using water as the hydrogen donor and 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene(4CzIPN)as the photocatalyst. 展开更多
关键词 PHOTOCATALYTIC multi-component synthesis Diazo compounds Radical reaction Quinoxalin-2(1H)-ones
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AVAILABILITY SIMULATION OF MULTI-COMPONENT SYSTEM BASED ON OPPORTUNISTIC MAINTENANCE POLICY 被引量:5
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作者 蔡景 左洪福 吕德峰 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2009年第3期219-223,共5页
A multi-component system has the long fixed maintenance time, so the opportunistic maintenance policy is adopted to put preventive replacement and corrective replacement together, so that the long fixed maintenance ti... A multi-component system has the long fixed maintenance time, so the opportunistic maintenance policy is adopted to put preventive replacement and corrective replacement together, so that the long fixed maintenance time can be shared by more than one component, and the system availability can be improved. Then, the generation characteristics of the random failure time are researched based on the replacement maintenance and the minima[ maintenance. Furthermore, by choosing the opportunistic replacement ages of each component as opti- mized variables, a simulation algorithm based on an opportunistic maintenance policy is designed to maximize the total availability. Finally, the simulation result shows the validity of the algorithm by an example. 展开更多
关键词 AVAILABILITY multi-component system ALGORITHMS opportunistic maintenance minimal maintenance
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Filmwise Condensation Heat Transfer Enhancement with Dropwise and Filmwise Coexisting Condensation Surfaces 被引量:4
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作者 马学虎 王补宣 +1 位作者 徐敦颀 林纪方 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1998年第2期5-12,共8页
Six surfaces were prepared with defferent surface division patterns for the experimental investigationof steam condensation heat transfer characteristics for dropwise and filmwise coexisting(DFC)condensationsurfaces u... Six surfaces were prepared with defferent surface division patterns for the experimental investigationof steam condensation heat transfer characteristics for dropwise and filmwise coexisting(DFC)condensationsurfaces under atmospheric pressure Dropwise condensation(DWC)was promoted with an ultrathin polytetrafluoroethylene(PTFE)film,which was prepared by the dynamic ion-beam mixed implantation(DIMI)method.The results showed that the condensation phenomena at the intersection between the dropwise andfilmwise condensation regios were quite different for different relative positions of the dropwise and filmwisecondensation regions.The experimental results revealed that the condensation heat transfer characteristics werehighly influenced by the surface division number and the relative area ratio of the dropwise and filmwise conden-sation regions.The impact of thesc findings on heat transfer enhancement mechanism for condensation heattransfer is discussed in detail. 展开更多
关键词 dropwise and filmwise coexisting CONDENSATION HEAT TRANSFER enhancement polymer FILM
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Multi-component assembly of luminescent rare earth hybrid materials 被引量:14
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作者 Qiuping Li Bing Yan 《Journal of Rare Earths》 SCIE EI CAS CSCD 2019年第2期113-123,共11页
This review focuses on the recent research progress in the multi-component assembly of luminescent rare earth hybrid materials, which is based on the luminescent rare earth compounds and two or more other building uni... This review focuses on the recent research progress in the multi-component assembly of luminescent rare earth hybrid materials, which is based on the luminescent rare earth compounds and two or more other building units, including the other photoactive species. It covers the multi-component luminescent rare earth hybrids which was assembled with different(a) organic-inorganic polymeric units,(b)nanoporous units,(c) nanoparticle composites or(d) other developing special units. Finally, future challenges and opportunities in this field are discussed. Herein it mainly focuses on the work of Yan's group in recent years. 展开更多
关键词 multi-component ASSEMBLY RARE earth ions Hybrid materials LUMINESCENCE
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Bifurcation behavior and coexisting motions in a time-delayed power system 被引量:4
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作者 马美玲 闵富红 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第3期78-86,共9页
With the increase of system scale, time delays have become unavoidable in nonlinear power systems, which add the complexity of system dynamics and induce chaotic oscillation and even voltage collapse events. In this p... With the increase of system scale, time delays have become unavoidable in nonlinear power systems, which add the complexity of system dynamics and induce chaotic oscillation and even voltage collapse events. In this paper, coexisting phenomenon in a fourth-order time-delayed power system is investigated for the first time with different initial conditions.With the mechanical power, generator damping factor, exciter gain, and time delay varying, the specific characteristic of the time-delayed system, including a discontinuous "jump" bifurcation behavior is analyzed by bifurcation diagrams, phase portraits, Poincar′e maps, and power spectrums. Moreover, the coexistence of two different periodic orbits and chaotic attractors with periodic orbits are observed in the power system, respectively. The production condition and existent domain of the coexistence phenomenon are helpful to avoid undesirable behavior in time-delayed power systems. 展开更多
关键词 chaotic oscillation time delays bifurcation diagrams coexisting motions
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Multi-component Dirac equation hierarchy and its multi-component integrable couplings system 被引量:8
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作者 夏铁成 尤福财 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第3期605-610,共6页
A general scheme for generating a multi-component integrable equation hierarchy is proposed. A simple 3M- dimensional loop algebra ~X is produced. By taking advantage of ~X a new isospectral problem is established and... A general scheme for generating a multi-component integrable equation hierarchy is proposed. A simple 3M- dimensional loop algebra ~X is produced. By taking advantage of ~X a new isospectral problem is established and then by making use of the Tu scheme the multi-component Dirac equation hierarchy is obtained. Finally, an expanding loop algebra ~FM of the loop algebra ~X is presented. Based on the ~FM, the multi-component integrable coupling system of the multi-component Dirac equation hierarchy is investigated. The method in this paper can be applied to other nonlinear evolution equation hierarchies. 展开更多
关键词 loop algebra zero curvature equation multi-component Dirac equation hierarchy multi-component integrable couplings system
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Multi-component AVO response of thin beds based on reflectance spectrum theory 被引量:7
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作者 Chen Tiansheng Liu Yang 《Applied Geophysics》 SCIE CSCD 2006年第1期27-36,共10页
Seismic AVO analysis now is one of the major criteria for recognizing potential hydrocarbon reservoirs. Volume scattering information that carries information of stratigraphic structure, lithology, and pore fluid is m... Seismic AVO analysis now is one of the major criteria for recognizing potential hydrocarbon reservoirs. Volume scattering information that carries information of stratigraphic structure, lithology, and pore fluid is more useful for seismic exploration. However, traditional AVO analysis is based on the Zoeppritz equation, which only contains single-interface information. Quantitative interpretation of the thin bed thickness is essential to thin bed structure interpretation, reservoir description, and lateral reservoir prediction. The reflectance spectrum equation based on the elastic wave propagation matrix in the frequency domain derived in this paper shows that both interfaces and intervals have an effect on amplitude. The equation includes information about both single interfaces and volume scattering. Since the reflectance spectrum equation is a continuous function of thin bed thickness and frequency, it is convenient to analyze the effects of a single frequency and bed thickness on the reflectance spectrum. Bed thickness is analyzable until the bed thickness is vanishingly small. These characteristics can't be achieved by Fourier transform. The propagation of seismic waves is complex and various wave modes exist simultaneously. The reflectance spectrum includes various propagating wave modes and multiples and is better for simulating multi-component thin bed AVO responses than the ray tracing method. 展开更多
关键词 AVO multi-component thin bed reflectance-spectnun.
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Recent progress of arsenic adsorption on TiO2 in the presence of coexisting ions: A review 被引量:15
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作者 Li Yan Shan Hu Chuanyong Jing 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2016年第11期74-85,共12页
Arsenic(As)-contaminated wastewater and groundwater pose a pressing environmental issue and worldwide concern. Adsorption of As using TiO_2materials, in combination with filtration,introduces a promising technology ... Arsenic(As)-contaminated wastewater and groundwater pose a pressing environmental issue and worldwide concern. Adsorption of As using TiO_2materials, in combination with filtration,introduces a promising technology for the treatment of As-contaminated water. This review presents an overview on the recent progress of the application of TiO_2for removal of As from wastewater and groundwater. The main focus is on the following three pressing issues that limit the field applications of TiO_2for As removal: coexisting ions, simulation of breakthrough curves, and regeneration and reuse of spent TiO_2materials. We first examined how the coexisting ions in water, especially high concentrations of cations in industrial wastewater,affect the efficacy of As removal using the TiO_2materials. We then discussed As breakthrough curves and the effect of compounded ions on the breakthrough curves. We successfully simulated the breakthrough curves by PHREEQC after integrating the CD-MUSIC model. We further discussed challenges facing the regeneration and reuse of TiO_2media for practical applications. We offer our perspectives on remaining issues and future research needs. 展开更多
关键词 Arsenic TiO2 adsorbent coexisting ions CD-MUSIC PHREEQC Regeneration
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Complex transitions between spike, burst or chaos synchronization states in coupled neurons with coexisting bursting patterns 被引量:2
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作者 古华光 陈胜根 李玉叶 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第5期281-292,共12页
We investigated the synchronization dynamics of a coupled neuronal system composed of two identical Chay model neurons. The Chay model Showed coexisting period-1 and period-2 bursting patterns as a parameter and initi... We investigated the synchronization dynamics of a coupled neuronal system composed of two identical Chay model neurons. The Chay model Showed coexisting period-1 and period-2 bursting patterns as a parameter and initial values are varied. We simulated multiple periodic and chaotic bursting patterns with non-(NS), burst phase (BS), spike phase (SS), complete (CS), and lag synchronization states. When the coexisting behavior is near period-2 bursting, the transitions of synchronization states of the coupled system follows very complex transitions that begins with transitions between BS and SS, moves to transitions between CS and SS, and to CS. Most initial values lead to the CS state of period-2 bursting while only a few lead to the CS state of period-I bursting. When the coexisting behavior is near period-1 bursting, the transitions begin with NS, move to transitions between SS and BS, to transitions between SS and CS, and then to CS. Most initial values lead to the CS state of period-1 bursting but a few lead to the CS state of period-2 bursting. The BS was identified as chaos synchronization. The patterns for NS and transitions between BS and SS are insensitive to initial values. The patterns for transitions between CS and SS and the CS state are sensitive to them. The number of spikes per burst of non-CS bursting increases with increasing coupling strength. These results not only reveal the initial value- and parameter- dependent synchronization transitions of coupled systems with coexisting behaviors, but also facilitate interpretation of various bursting patterns and synchronization transitions generated in the nervous system with weak coupling strength. 展开更多
关键词 synchronization transition phase synchronization coexisting attractors coupled neuronal system
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Multi-scale and multi-component digital core construction and elastic property simulation 被引量:6
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作者 Cui Li-Kai Sun Jian-Meng +1 位作者 Yan Wei-Chao Dong Huai-Min 《Applied Geophysics》 SCIE CSCD 2020年第1期26-36,167,共12页
The conventional digital core models are usually small in size and have difficulty in representing the complex structures of heterogeneous rocks;Therefore,the parameters of simulated rock physics are difficult to be r... The conventional digital core models are usually small in size and have difficulty in representing the complex structures of heterogeneous rocks;Therefore,the parameters of simulated rock physics are difficult to be referenced.In this study,we propose a feasible simulation method for obtaining multi-scale and multi-component digital cores based on three types of sandstone samples.In the proposed method,the plug and subplug samples are scanned via micro-computed tomography at different resolutions.Furthermore,the images are precisely registered using the proposed hybrid image registration method.In case of high-resolution images,the traditional segmentation method is used to segment the cores into pores and minerals.Subsequently,we established the relations between the gray values and the porosity/mineral content in case of the low-resolution images based on the registered domains and the relation curves were applied to the segmentation of the low-resolution images.The core images constitute the multi-scale and multi-component digital core models after segmentation.Further,the elastic properties of the three samples were simulated at both fine and coarse scales based on the multi-scale and multi-component digital core models,and four component models were considered.The results show that the multi-scale and multi-component digital core models can overcome the representative limits of the conventional digital core models and accurately characterize pores and minerals at different scales.The numerical results of the elastic modulus are more representative at large scales,and considerably reliable results can be obtained by appropriately considering the minerals. 展开更多
关键词 elastic properties digital core MULTI-SCALE multi-component
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Perivascular epithelioid cell tumor of the liver coexisting with a gastrointestinal stromal tumor 被引量:6
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作者 Carlos Eduardo Paiva Francisco Alves Moraes Neto +2 位作者 Abbas Agaimy Maria Aparecida Custódio Domingues Silvia Regina Rogatto 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第5期800-802,共3页
Approximately 10% of patients with gastrointestinal stromal tumors (GIST) develop other neoplasms, either synchronously or metachronously. In this report we describe coexistence of a gastrointestinal stromal tumor and... Approximately 10% of patients with gastrointestinal stromal tumors (GIST) develop other neoplasms, either synchronously or metachronously. In this report we describe coexistence of a gastrointestinal stromal tumor and a hepatic perivascular epithelioid cell tumor (PEComa) in a 51-year-old woman with no evidence of tuberous sclerosis. A subcapsular hepatic nodule (0.8 cm in diameter) was found during surgery for symptomatic gastric neoplasm (15 cm in diameter) arising from the lesser curvature. Both tumors revealed histomorphological and immunohistochemical features confirming a diagnosis of a small incidental hepatic PEComa and a high risky extramural gastric GIST, respectively. The patient remained disease-free 25 mo after surgery with no evidence of tumor recurrence or new neoplasms. To our knowledge, this is the first report of PEComa in a patient with GIST. Hepatic lesions detected synchronously or metachronously in patients with GISTs may represent histogenetically distinct lesions and should be sampled to confirm or exclude metastatic GISTs. 展开更多
关键词 Gastrointestinal stromal tumors PECOMA coexistENCE LIVER SYNCHRONOUS
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Possible observation of shape-coexisting configurations in even–even midshell isotones with N=104:a systematic total Routhian surface calculation 被引量:2
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作者 Qing-Zhen Chai Wei-Juan Zhao +1 位作者 Hua-Lei Wang Min-Liang Liu 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第3期92-101,共10页
Systematic total Routhian surface calculations for even–even N = 104 midshell isotones with 66≤Z≤82 have been carried out based on a more realistic diffuse-surface deformed Woods–Saxon nuclear potential in (β_2, ... Systematic total Routhian surface calculations for even–even N = 104 midshell isotones with 66≤Z≤82 have been carried out based on a more realistic diffuse-surface deformed Woods–Saxon nuclear potential in (β_2, γ, β_4) deformation space, focusing on the rotation-induced shapecoexisting phenomena. As an example and basic test, the oblate property at the ground state in ^(184)Hg is well reproduced and the microscopic origin is analyzed from the single-particle structure. The present calculated results are compared with available experimental information, showing a good agreement. It is systematically found that in this isotonic chain several bands with different shapes(e.g., prolate, oblate and superdeformed prolate bands, seven non-collective band) may show a strong competition and coexisting phenomenon at a certain domain of the rotational frequency. 展开更多
关键词 TOTAL Routhian surface CALCULATION Woods–Saxon potential Shape coexistENCE Rotation Midshell nuclei
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Effect of Melt Superheating Treatment on Directional Solidification Interface Morphology of Multi-component Alloy 被引量:9
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作者 Changshuai Wang Jun Zhang Lin Liu Hengzhi Fu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2011年第7期668-672,共5页
The influence of melt superheating treatment on the solid/liquid (S/L) interface morphology of directionally solidified Ni-based superalloy DZ125 is investigated to elucidate the relationship between melt characteri... The influence of melt superheating treatment on the solid/liquid (S/L) interface morphology of directionally solidified Ni-based superalloy DZ125 is investigated to elucidate the relationship between melt characteristic and S/L interface stability. The results indicate that the interface morphology is not only related to the withdrawal velocity (R) but also to the melt superheating temperature (Ts) when the thermal gradient of solidification interface remains constant for different Ts with appropriate superheating treatment regulation. The interface morphology changes from cell to plane at R of 1.1 μm/s when Ts increases from 1500°C to 1650°C, and maintains plane with further elevated Ts of 1750°C. However, the interface morphology changes from coarse dendrite to cell and then to cellular dendrite at R of 2.25 μm/s when Ts increases from 1500°C to 1650°C and then to 1750°C. It is proved that the solidification onset temperature and the solidification interval undergo the nonlinear variation when Ts increases from 1500°C to 1680°C, and the turning point is 1650°C at which the solidification onset temperature and the solidification interval are all minimum. This indicates that the melt superheating treatment enhances the solidification interface stability and has important effect on the solidification characteristics. 展开更多
关键词 Melt superheating treatment Directional solidification interface morphology Solidification characteristics multi-component alloy
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Multi-component opportunistic maintenance optimization for wind turbines with consideration of seasonal factor 被引量:4
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作者 SU Chun HU Zhao-yong LIU Yang 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第2期490-499,共10页
Aiming at wind turbines,the opportunistic maintenance optimization is carried out for multi-component system,where minimal repair,imperfect repair,replacement as well as their effects on component’s effective age are... Aiming at wind turbines,the opportunistic maintenance optimization is carried out for multi-component system,where minimal repair,imperfect repair,replacement as well as their effects on component’s effective age are considered.At each inspection point,appropriate maintenance mode is selected according to the component’s effective age and its maintenance threshold.To utilize the maintenance opportunities for the components among the wind turbines,opportunistic maintenance approach is adopted.Meanwhile,the influence of seasonal factor on the component’s failure rate and improvement factor’s decrease with the increase of repair’s times are also taken into account.The maintenance threshold is set as the decision variable,and an opportunistic maintenance optimization model is proposed to minimize wind turbine’s life-cycle maintenance cost.Moreover,genetic algorithm is adopted to solve the model,and the effectiveness is verified with a case study.The results show that based on the component’s inherent reliability and maintainability,the proposed model can provide optimal maintenance plans accordingly.Furthermore,the higher the component’s reliability and maintainability are,the less the times of repair and replacement will be. 展开更多
关键词 wind turbine RELIABILITY seasonal factor multi-component maintenance opportunistic maintenance
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Layout problem of multi-component systems arising for improving maintainability 被引量:5
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作者 罗旭 杨拥民 +2 位作者 葛哲学 温熙森 官凤娇 《Journal of Central South University》 SCIE EI CAS 2014年第5期1833-1841,共9页
To improve the mainlainability design efficiency and quality, a layout optimization method for maintainability of multi-component systems was proposed. The impact of the component layout design on system maintainabili... To improve the mainlainability design efficiency and quality, a layout optimization method for maintainability of multi-component systems was proposed. The impact of the component layout design on system maintainability was analyzed, and the layout problem for maintainability was presented. It was formulated as an optimization problem, where maintainability, layout space and distance requirement were formulated as objective functions. A multi-objective particle swarm optimization algorithm, in which the constrained-domination relationship and the update strategy of the global best were simply modified, was then used to obtain Pareto optimal solutions for the maintainability layout design problem. Finally, application in oxygen generation system of a spacecraft was studied in detail to illustrate the effectiveness and usefulness of the proposed method. The results show that the concurrent maintainability design can be carried out during the layout design process by solving the layout optimization problem for maintainability. 展开更多
关键词 MAINTAINABILITY layout problem OPTIMIZATION multi-component system multi-objective particle swarm optimization
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Study of Cell Behaviors on Anodized TiO_2 Nanotube Arrays with Coexisting Multi-Size Diameters 被引量:2
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作者 Yifan Chen Jiahua Ni +6 位作者 Hongliu Wu Ruopeng Zhang Changli Zhao Wenzhi Chen Feiqing Zhang Shaoxiang Zhang Xiaonong Zhang 《Nano-Micro Letters》 SCIE EI CAS 2016年第1期61-69,共9页
It has been revealed that the different morphologies of anodized TiO_2 nanotubes, especially nanotube diameters, triggered different cell behaviors. However, the influence of TiO_2 nanotubes with coexisting multi-size... It has been revealed that the different morphologies of anodized TiO_2 nanotubes, especially nanotube diameters, triggered different cell behaviors. However, the influence of TiO_2 nanotubes with coexisting multi-size diameters on cell behaviors is seldom reported. In this work, coexisting four-diameter TiO_2 nanotube samples, namely,one single substrate with the integration of four different nanotube diameters(60, 150, 250, and 350 nm), were prepared by repeated anodization. The boundaries between two different diameter regions show well-organized structure without obvious difference in height. The adhesion behaviors of MC3T3-E1 cells on the coexisting fourdiameter TiO_2 nanotube arrays were investigated. The results exhibit a significant difference of cell density between smaller diameters(60 and 150 nm) and larger diameters(250 and 350 nm) within 24 h incubation with the coexistence of different diameters, which is totally different from that on the single-diameter TiO_2 nanotube arrays. The coexistence of four different diameters does not change greatly the cell morphologies compared with the singlediameter nanotubes. The findings in this work are expected to offer further understanding of the interaction between cells and materials. 展开更多
关键词 coexisting multi-size TiO2 nanotubes Repeated anodization MC3T3-E1 cells CELL adhesion behaviors Cell-material interaction
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