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Isotopic dependence of the yield ratios of light fragments from different projectiles and their unified neutron skin thicknesses
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作者 Ting-Zhi Yan Shan Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期228-236,共9页
The yield ratios of neutron-proton(R(n/p))and^(3)H-^(3)He(R(^(3)H∕^(3)He))with reduced rapidity from 0 to 0.5 were simulated at 50 MeV/u even-even ^(36−56)Ca+^(40)Ca,even-even ^(48−78)Ni+^(58)Ni,and ^(100−139)Sn(ever... The yield ratios of neutron-proton(R(n/p))and^(3)H-^(3)He(R(^(3)H∕^(3)He))with reduced rapidity from 0 to 0.5 were simulated at 50 MeV/u even-even ^(36−56)Ca+^(40)Ca,even-even ^(48−78)Ni+^(58)Ni,and ^(100−139)Sn(every third isotopes)+112 Sn for full reduced impact parameters using the isospin-dependent quantum molecular dynamics(IQMD)model.The neutron and proton density distributions and root-mean-square radii of the reaction systems were obtained using the Skyrme-Hartree-Fock model,which was used for the phase space initialization of the projectile and target in IQMD.We defined the unified neutron skin thickness asΔRnp=<r^(2)>^(1∕2) n−<r^(2)>^(1∕2)p,which was negative for neutron-deficient nuclei.The unifiedΔRnp values for nuclei with the same relative neutron excess from different isotopic chains were nearly equal,except for extreme neutron-rich isotopes,which is a type of scaling behavior.The yield ratios of the three isotopic chain-induced reactions,which depended on the reduced impact parameter and unified neutron skin thickness,were studied.The results showed that both R(n/p)and R(^(3)H∕^(3)He)decreased with a reduced impact parameter for extreme neutron-deficient isotopes;however,they increased with reduced impact parameters for extreme neutron-rich isotopes,and increased with theΔRnp of the projectiles for all reduced impact parameters.In addition,a scaling phenomenon was observed betweenΔR np and the yield ratios in peripheral colli-sions from different isotopic chain projectiles(except for extreme neutron-rich isotopes).Thus,R(n/p)and R(^(3)H∕^(3)He)from peripheral collisions were suggested as experimental probes for extracting the neutron or proton skin thicknesses of non-extreme neutron-rich nuclei from different isotopic chains. 展开更多
关键词 Exotic nuclei Unified neutron skin thickness Yield ratios IQMD
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Red cell distribution width/platelet ratio estimates the 3-year risk of decompensation in Metabolic Dysfunction-Associated Steatotic Liver Disease-induced cirrhosis
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作者 Marcello Dallio Mario Romeo +8 位作者 Paolo Vaia Salvatore Auletta Simone Mammone Marina Cipullo Luigi Sapio Angela Ragone Marco Niosi Silvio Naviglio Alessandro Federico 《World Journal of Gastroenterology》 SCIE CAS 2024年第7期685-704,共20页
BACKGROUND For compensated advanced chronic liver disease(cACLD)patients,the first decompensation represents a dramatically worsening prognostic event.Based on the first decompensation event(DE),the transition to deco... BACKGROUND For compensated advanced chronic liver disease(cACLD)patients,the first decompensation represents a dramatically worsening prognostic event.Based on the first decompensation event(DE),the transition to decompensated advanced chronic liver disease(dACLD)can occur through two modalities referred to as acute decompensation(AD)and non-AD(NAD),respectively.Clinically Significant Portal Hypertension(CSPH)is considered the strongest predictor of decompensation in these patients.However,due to its invasiveness and costs,CSPH is almost never evaluated in clinical practice.Therefore,recognizing noninvasively predicting tools still have more appeal across healthcare systems.The red cell distribution width to platelet ratio(RPR)has been reported to be an indicator of hepatic fibrosis in Metabolic Dysfunction-Associated Steatotic Liver Disease(MASLD).However,its predictive role for the decompensation has never been explored.AIM In this observational study,we investigated the clinical usage of RPR in predicting DEs in MASLD-related cACLD patients.METHODS Fourty controls and 150 MASLD-cACLD patients were consecutively enrolled and followed up(FUP)semiannually for 3 years.At baseline,biochemical,clinical,and Liver Stiffness Measurement(LSM),Child-Pugh(CP),Model for End-Stage Liver Disease(MELD),aspartate aminotransferase/platelet count ratio index(APRI),Fibrosis-4(FIB-4),Albumin-Bilirubin(ALBI),ALBI-FIB-4,and RPR were collected.During FUP,DEs(timing and modaities)were recorded.CSPH was assessed at the baseline and on DE occurrence according to the available Clinical Practice Guidelines.RESULTS Of 150 MASLD-related cACLD patients,43(28.6%)progressed to dACLD at a median time of 28.9 months(29 NAD and 14 AD).Baseline RPR values were significantly higher in cACLD in comparison to controls,as well as MELD,CP,APRI,FIB-4,ALBI,ALBI-FIB-4,and LSM in dACLD-progressing compared to cACLD individuals[all P<0.0001,except for FIB-4(P:0.007)and ALBI(P:0.011)].Receiving operator curve analysis revealed RPR>0.472 and>0.894 as the best cut-offs in the prediction respectively of 3-year first DE,as well as its superiority compared to the other non-invasive tools examined.RPR(P:0.02)and the presence of baseline-CSPH(P:0.04)were significantly and independently associated with the DE.Patients presenting baseline-CSPH and RPR>0.472 showed higher risk of decompensation(P:0.0023).CONCLUSION Altogether these findings suggest the RPR as a valid and potentially applicable non-invasive tool in the prediction of timing and modalities of decompensation in MASLD-related cACLD patients. 展开更多
关键词 Liver cirrhosis Red blood cell distribution width Red blood cell distribution width to platelet ratio Translational Medicine Prognostic biomarker
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Application of neutrophil-lymphocyte ratio and red blood cell distribution width in diabetes mellitus complicated with heart failure
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作者 Jie Pang Lin-Yan Qian +1 位作者 Ping Lv Xiao-Ru Che 《World Journal of Diabetes》 SCIE 2024年第6期1226-1233,共8页
BACKGROUND Accumulating clinical evidence has shown that diabetes mellitus(DM)is a serious risk factor for cardiovascular disorders and an important factor for adverse cardiovascular events.AIM To explore the value of... BACKGROUND Accumulating clinical evidence has shown that diabetes mellitus(DM)is a serious risk factor for cardiovascular disorders and an important factor for adverse cardiovascular events.AIM To explore the value of the combined determination of the neutrophil-lymphocyte ratio(NLR)and red blood cell distribution width(RDW)in the early diagnosis and prognosis evaluation of DM complicated with heart failure(HF).METHODS We retrospectively analyzed clinical data on 65 patients with type 2 DM(T2DM)complicated with HF(research group,Res)and 60 concurrent patients with uncomplicated T2DM(control group,Con)diagnosed at Zhejiang Provincial People’s Hospital between January 2019 and December 2021.The NLR and RDW values were determined and comparatively analyzed,and their levels in T2DM+HF patients with different cardiac function grades were recorded.The receiver operating characteristic(ROC)curves were plotted to determine the NLR and RDW values(alone and in combination)for the early diagnosis of HF.The correlation between NLR and RDW with the presence or absence of cardiac events was also investigated.RESULTS Higher NLR and RDW levels were identified in the Res vs the Con groups(P<0.05).The NLR and RDW increased gradually and synchronously with the deterioration of cardiac function in the Res group,with marked differences in their levels among patients with grade II,III,and IV HF(P<0.05).ROC curve analysis revealed that NLR combined with RDW detection had an area under the curve of 0.915,a sensitivity of 76.9%,and a specificity of 100%for the early diagnosis of HF.Furthermore,HF patients with cardiac events showed higher NLR and RDW values compared with HF patients without cardiac events.CONCLUSION NLR and RDW were useful laboratory indicators for the early diagnosis of DM complicated with HF,and their joint detection was beneficial for improving diagnostic efficiency.Additionally,NLR and RDW values were directly proportional to patient outcomes. 展开更多
关键词 Neutrophil-lymphocyte ratio Red blood cell distribution width Type 2 diabetes Heart failure Early diagnosis
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Three-Dimensional Direct Numerical Simulation of Flow past A Near-Wall Circular Cylinder:Combined Effects of Gap Ratio and Boundary Layer Thickness on Flow Profiles and Pressure Distribution
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作者 YING Chao HUA Yang +1 位作者 WEI Yu-han JI Chun-ning 《China Ocean Engineering》 SCIE EI CSCD 2023年第6期948-961,共14页
Three-dimensional direct numerical simulations of the wake flow downstream of a near-wall circular cylinder at different gap ratios and boundary layer thicknesses are carried out by using the iterative immersed bounda... Three-dimensional direct numerical simulations of the wake flow downstream of a near-wall circular cylinder at different gap ratios and boundary layer thicknesses are carried out by using the iterative immersed boundary method.The non-dimensional gap between the cylinder and the wall,G/D=0.2,0.6 and 1.0,the non-dimensional boundary layer thickness,δ/D=0.0,0.7 and 1.6,the Reynolds number,Re=350,and the aspect ratio of the cylinder,L/D=25are adopted.High-resolution visualizations of the complex vortex structures at differentδ/D and G/D are presented.The transition of the streamwise vortex mode,the combined effects ofδ/D and G/D on the flow statistics,the pressure and shear stress distribution and the hydrodynamic forces are analyzed.Results show that with decreasing G/D and increasingδ/D,the gap flow and its vortex-shedding are significantly weakened,together with an elongated wake and an enlarged low-velocity area near the wall,leading to the wake mode transition from the two-sided to one-sided vortex-shedding.Different relative positions of the cylinder regarding the boundary layer alter the flow features of the shear layers.With an increase inδ/D,the front stagnation point shifts to the upper surface,and the distance between the flow divergence point and the maximum pressure position increases.The mean drag coefficient and r.m.s.values of drag and lift coefficients decrease with a decrease in G/D and an increase inδ/D,while the mean lift coefficient increases with decreasing G/D but decreases with increasingδ/D. 展开更多
关键词 cylinder wake near-wall effect direct numerical simulation boundary layer thickness gap ratio
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Crustal thicknesses and Poisson's ratios beneath the Chuxiong-Simao Basin in the Southeast Margin of the Tibetan Plateau 被引量:16
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作者 ZiQi Zhang Yuan Gao 《Earth and Planetary Physics》 CSCD 2019年第1期69-84,共16页
In the Southeast Margin of the Tibetan Plateau, low-velocity sedimentary layers that would significantly affect the accuracy of the H-κ stacking of receiver functions are widely distributed.In this study, we use tele... In the Southeast Margin of the Tibetan Plateau, low-velocity sedimentary layers that would significantly affect the accuracy of the H-κ stacking of receiver functions are widely distributed.In this study, we use teleseismic waveform data of 475 events from 97 temporary broadband seismometers deployed by ChinArray Phase I to obtain crustal thicknesses and Poisson's ratios within the Chuxiong-Simao Basin and adjacent area, employing an improved method in which the receiver functions are processed through a resonance-removal filter, and the H-κ stacking is time-corrected.Results show that the crustal thickness ranges from 30 to 55 km in the study area, reaching its thickest value in the northwest and thinning toward southwest, southeast and northeast.The apparent variation of crustal thickness around the Red River Fault supports the view of southeastern escape of the Tibetan Plateau.Relatively thin crustal thickness in the zone between Chuxiong City and the Red River Fault indicates possible uplift of mantle in this area.The positive correlation between crustal thickness and Poisson's ratio is likely to be related to lower crust thickening.Comparison of results obtained from different methods shows that the improved method used in our study can effectively remove the reverberation effect of sedimentary layers. 展开更多
关键词 receiver functions SEDIMENTARY layer SOUTHEAST MARGIN of the Tibetan Plateau CRUSTAL thickness Poisson's ratio Chuxiong-Simao Basin
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Crustal thickness and v_P/v_S ratio in Shanxi Graben, China 被引量:5
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作者 Yutao Shi Yuan Gao Honglin Jing 《Earthquake Science》 2014年第6期589-597,共9页
Shanxi Graben is in the middle part of the North China Craton, from south to north. With the teleseismic data recorded by Regional Seismograph Networks and the temporary ZBnet-W Seismic Array around east part of Shanx... Shanxi Graben is in the middle part of the North China Craton, from south to north. With the teleseismic data recorded by Regional Seismograph Networks and the temporary ZBnet-W Seismic Array around east part of Shanxi Graben, we measured the crustal thickness and Vp/Vs ratio beneath each station using the H-K stack of receiver functions. The observed crustal thickness shows obvious lateral variation, increasing gradually from east to west in the Shanxi Graben. Beneath the Shanxi Graben the crust is relatively thicker than both sides of the south and the north. In addition, the Vp/Vs ratio in the north of study zone is higher than that in the south. The highest Vp/Vs ratio exists in the crust of the Xinding basin and the Datong basin. Our study also suggests that high velocity ratio might result from the strong activities of the magmation and volcanism. 展开更多
关键词 Shanxi Graben North China Craton (NCC) Receiver function Crustal thickness - Crustal Vp/Vs ratio
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Vibration of Visco-Elastic Parallelogram Plate with Parabolic Thickness Variation 被引量:2
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作者 Arun Kumar Gupta Anuj Kumar Yogesh Kumar Gupta 《Applied Mathematics》 2010年第2期128-136,共9页
The main objective of the present investigation is to study the vibration of visco-elastic parallelogram plate whose thickness varies parabolically. It is assumed that the plate is clamped on all the four edges and th... The main objective of the present investigation is to study the vibration of visco-elastic parallelogram plate whose thickness varies parabolically. It is assumed that the plate is clamped on all the four edges and that the thickness varies parabolically in one direction i.e. along length of the plate. Rayleigh-Ritz technique has been used to determine the frequency equation. A two terms deflection function has been used as a solution. For visco-elastic, the basic elastic and viscous elements are combined. We have taken Kelvin model for visco-elasticity that is the combination of the elastic and viscous elements in parallel. Here the elastic element means the spring and the viscous element means the dashpot. The assumption of small deflection and linear visco-elastic properties of “Kelvin” type are taken. We have calculated time period and deflection at various points for different values of skew angles, aspect ratio and taper constant, for the first two modes of vibration. Results are supported by tables. Alloy “Duralumin” is considered for all the material constants used in numerical 展开更多
关键词 VIBratioN PARALLELOGRAM PLATE VISCO-ELASTIC Mechanics PARABOLIC thickness ASPECT ratio
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Research on the squeeze cast technology of the castings with large ratio of height to thickness 被引量:1
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作者 LI Chen-xi SAN Jing-chao +3 位作者 XU Na CAO Liang BAI Yan-hua LI Rong-de 《China Foundry》 SCIE CAS 2005年第4期264-267,共4页
The squeeze cast technology is only applicable, at present, to the castings with a ratio of height to thickness less than 3.5. Researching the squeeze cast technology for castings with a large ratio of height to thick... The squeeze cast technology is only applicable, at present, to the castings with a ratio of height to thickness less than 3.5. Researching the squeeze cast technology for castings with a large ratio of height to thickness will broaden the applicable range of the advanced casting technology. This paper describes a study of the temperature distribution during solidification for castings with a ratio of height to thickness of 7 by the methods of experiment and computer simulation. The shrinkage porosity distribution in the castings and the mechanical properties of the castings were also researched. The experimental and simulated results show that increasing squeeze force, or enhancing mold temperature, cannot reduce the shrinkage porosities in the castings. When castings solidify in a sequential manner and the squeeze force effectively acts on the surface of the liquid metal, the shrinkage porosities in the castings are eliminated and mechanical properties are clearly improved. 展开更多
关键词 SQUEEZE CAST CASTINGS with LARGE ratio of height to thickness sequence solidification SHRINKAGE porosity
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The comparison between laser screw welding and resistant spot welding of lap joint with large thickness ratio 被引量:2
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作者 Wu Wenyong Yang Zhi Yue shuangcheng 《China Welding》 CAS 2021年第2期58-66,共9页
The present paper investigates the welding forming,microstructure and shear tensile test of lap joints with large thickness ratio which were fabricated by laser screw welding(LSW)and resistant spot welding(RSW).The co... The present paper investigates the welding forming,microstructure and shear tensile test of lap joints with large thickness ratio which were fabricated by laser screw welding(LSW)and resistant spot welding(RSW).The comparison was conducted on two kinds of lap joints,galvanized sheet and hot pressed steel(GS-HPS),galvanized sheet and high strength steel(GS-HS).The microstructure and fracture morphology were analyzed by optical microscope.It was demonstrated that with large thickness ratio the sound lap joint of GS-HS could be obtained by LSW regardless of the irradiation of laser beam from thick metal to sheet or otherwise,and the morphology shows it is better when the laser is irradiated on the thick metal.Nevertheless,when the laser beam was applied on thick metal of HPS,blind hole or blowhole was formed in the center of joint,which is attributed to the shrinkage during solidification of the molten pool.Small pores or dispersed porosity appeared on the faying face of the joint without predetermined gap which provides the degassing.However,the increase of predetermined gap could reduce the shear strength and nugget size.Two kinds of joints made by LSW have superior shear strength than those made by RSW when the laser were applied on galvanized sheet. 展开更多
关键词 Large thickness ratio laser screw welding hot pressed steel
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Failure behavior and mechanical properties of novel dieless clinched joints with different sheet thickness ratios 被引量:1
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作者 QIN Deng-lin CHEN Chao 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第9期3077-3087,共11页
As one of the advanced and efficient means of joining,the clinching process is capable of joining sheets with different materials or different sheet thicknesses.In this article,a novel modified clinching process,i.e.,... As one of the advanced and efficient means of joining,the clinching process is capable of joining sheets with different materials or different sheet thicknesses.In this article,a novel modified clinching process,i.e.,the dieless clinching process,was executed to join AA6061 aluminum alloy with sheet thicknesses of 1.5,2.0,2.5 and 3.0 mm according to different sheet stack-ups.The geometrical characteristics,microhardness distribution,failure behavior,static strength,absorbed energy and instantaneous stiffness of the novel dieless joint were gotten and investigated.The results indicated that the sheet thickness ratio has a notable effect on the failure behavior and mechanical properties of the novel dieless clinched joint,and a relatively large sheet thickness ratio can improve the joint performance when joining sheets with different sheet thicknesses. 展开更多
关键词 joining clinching process sheet thickness ratio failure behavior mechanical properties
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OsDA1 positively regulates grain width in rice
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作者 Cong Li Jun Liu +4 位作者 Liya Zhang Tao Li Hongyu Li Bin Liu Tao Zhao 《The Crop Journal》 SCIE CSCD 2024年第1期92-101,共10页
The size and shape of rice grains influence their yield and commercial value.We investigated the role of OsDA1,a rice homolog of the Arabidopsis DA1 gene,in regulating grain size and shape.OsDA1 was highly expressed i... The size and shape of rice grains influence their yield and commercial value.We investigated the role of OsDA1,a rice homolog of the Arabidopsis DA1 gene,in regulating grain size and shape.OsDA1 was highly expressed in young spikelets and glumes.Its overexpression led to enlarged seeds with increased width and decreased length/width ratio(LWR)and knocking out OsDA1 reduced grain width and increased grain length and LWR.A R310K point mutation in the DA1-like domain is a potential target for breeding for increased grain width and length.OsDA1 interacted with TCP gene-family proteins to regulate grain size and shape.Our findings deepen our understanding of the molecular mechanisms underlying grain size regulation and provide useful information for improving grain yield. 展开更多
关键词 RICE Osda1 Grain size Grain shape Grain length/width ratio TCP
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Study of crustal thickness and poisson's ratio of the south of Erenhot area by teleseismic receiver function
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作者 Lei Jiang Yonghong Duan +2 位作者 Yanna Zhao Yong Qiu Cheng Li 《Earthquake Science》 CSCD 2018年第4期215-223,共9页
The Xing’an Mongolian Orogenic Belt(XMOB) and the northern margin of North China Craton(NCC) have undergone multistage tectonic superimposition and the tectonic evolution is extremely complicated. We collect the tele... The Xing’an Mongolian Orogenic Belt(XMOB) and the northern margin of North China Craton(NCC) have undergone multistage tectonic superimposition and the tectonic evolution is extremely complicated. We collect the teleseismic data of 44 temporary broadband seismic stations deployed in the XMOB and the northern margin of NCC to calculate the P wave receiver functions. The crustal thickness and average crustal ratio as well as the Poisson’s ratios beneath 33 stations are estimated using the H-κ stacking method. The results show:(1) the crustal thickness of the study area ranges from 38.7 to 42.7 km, with an average thickness of 41.2 km. There is a great difference in crustal thickness on both sides of Solonker suture zone. The characteristics of crustal thickness support the geodynamic model that the Paleo-Asian Ocean subducted and closed at the Solonker suture zone.(2) The Poisson’s ratios in the study area are low, ranging from 0.215 to 0.277, with an average value of 0.243, suggesting that the rock composition of the area is dominated by felsic-acid rocks.(3) There exists a negative correlation between the Poisson’s ratio and the crustal thickness. Combined with the lower values of Poisson’s ratio, we speculate that the delamination is the major mechanism in crustal extension and thinning in the study area. 展开更多
关键词 Xing'an mongolia orogenic belt northern margin of North China Craton receiver function crustal thickness poisson's ratio
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Impacts of laser pulse width and target thickness on laser micro-propulsion performance
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作者 Sibo WANG Bangdeng DU +6 位作者 Baosheng DU Yongzan ZHENG Yanji HONG Jifei YE Baoyu XING Chenglin LI Yonghao ZHANG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2022年第10期113-126,共14页
In order to optimize the laser ablation performance of a micro-thruster with 1U dimensions,which employs a micro semiconductor laser,the impacts of pulse width and glycidyl azide polymer(GAP)thickness on thrust perfor... In order to optimize the laser ablation performance of a micro-thruster with 1U dimensions,which employs a micro semiconductor laser,the impacts of pulse width and glycidyl azide polymer(GAP)thickness on thrust performance were researched.The results showed that with a GAP thickness of 200μm,the single-pulse impulse(I)increased gradually with the increase in the laser pulse width from 50 to 800μs,while the specific impulse(I_(sp)),impulse coupling coefficient(Cm)and ablation efficiency(η)all reached optimal values with a 200μs pulse width.It is worth noting that the optimal pulse width is identical to the ignition delay time.Both Cmandηpeaked with a pulse width of 200μs,reaching 242.22μN W^(-1)and 35.4%,respectively.With the increase in GAP thickness,I and Cmincreased gradually.GAP of different thicknesses corresponded to different optimal laser pulse widths.Under a certain laser pulse width,the optimal GAP thickness should be the most vertical thickness of the ablation pit,and the various propulsion performance parameters at this time were also optimal.With the current laser parameters,the optimal GAP thickness was approximately 150μm,I_(sp)was approximately 322.22 s,andηwas approximately 34.94%. 展开更多
关键词 laser micro-propulsion pulse width target thickness specific impulse ablation efficiency
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Fabrication and Property of SiC Ceramic with Large Thickness/Diameter Ratios
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作者 TAN Lin HE Qianglong +2 位作者 HU Lanxin TIAN Tian WANG Weimin 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2020年第3期506-513,共8页
Silicon carbide ceramics with different thicknesses/diameter ratios were prepared by using ultra-fine silicon carbide powder with the sintering additives of 1.0 wt% boron and 1.5 wt% carbon. The influence of thickness... Silicon carbide ceramics with different thicknesses/diameter ratios were prepared by using ultra-fine silicon carbide powder with the sintering additives of 1.0 wt% boron and 1.5 wt% carbon. The influence of thickness/diameter ratio on the microstructure and density of SiC ceramics was investigated in detail. The experimental results show that the addition of boron and carbon sintering aids can promote the densification process of SiC ceramic, leading to the low sintering temperature and improve mechanical properties. At 1950 ℃, SiC ceramic with a density of 99% exhibits Young's modulus, hardness, and flexural strength of 476 MPa, 28.3 GPa, and 334 MPa, respectively. It is found that long holding time has a positive effect on the uniformity of the microstructure and density distribution of SiC ceramics with large thickness/diameter ratios. Additionally, the sintering additive of boron can solid-solve into SiC, and then facilitate the phase transformation of SiC to form 6H-SiC and 4H-SiC composite ceramics. 展开更多
关键词 SIC large thickness/diameter ratios mechanical properties UNIFORMITY
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Study of Thermally Induced Vibration of Non-Homogeneous Trapezoidal Plate with Parabolically Thickness Variation in Both Directions
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作者 Kavita Satish Kumar Pragati Sharma 《Applied Mathematics》 2016年第12期1283-1296,共14页
The present analysis demonstrates the thermal effect on vibrations of a symmetric, non-homoge- neous trapezoidal plate with parabolically varying thickness in both directions. The variation in Young’s modulus and mas... The present analysis demonstrates the thermal effect on vibrations of a symmetric, non-homoge- neous trapezoidal plate with parabolically varying thickness in both directions. The variation in Young’s modulus and mass density is the main cause for the occurrence of non-homogeneity in plate’s material. In this consideration, density varies linearly in one direction. The governing differential equations have been derived by Rayleigh-Ritz method in order to attain fundamental frequencies. With C-S-C-S boundary condition, a two term deflection function has been considered. The effect of structural parameters such as taper constants, thermal gradient, aspect ratio and non-homogeneity constant has been investigated for first two modes of vibration. The obtained numerical results have been presented in tabular and graphical form. 展开更多
关键词 VIBratioN Trapezoidal Plate Taper Constants Thermal Gradient Aspect ratio Non-Homogeneity Parabolically thickness Linearly Density
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Study of Temperature Behaviour on Thermally Induced Vibration of Non-Homogeneous Trapezoidal Plate with Bi-Linearly Varying Thickness
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作者 Kavita Satish Kumar Pragati Sharma 《Journal of Applied Mathematics and Physics》 2016年第10期1936-1948,共14页
The main aim of the present work is to study the linear temperature behaviour of a non-homogeneous trapezoidal plate whose thickness varies linearly in both directions. The temperature behaviour considered linear alon... The main aim of the present work is to study the linear temperature behaviour of a non-homogeneous trapezoidal plate whose thickness varies linearly in both directions. The temperature behaviour considered linear along the length of the plate. Non-homogeneity in plate arises due to variation in density along the length of the plate. The two-term deflection function with clamped-simply supported-clamped-simply supported boundary condition is taken into consideration. The effect of structural parameters such as taper constants, thermal gradient, non-homogeneity constant and aspect ratio has been studied. Rayleigh-Ritz method is used to solve the governing differential equations and to obtain the fundamental frequencies for the first two modes of vibration. Results are presented in graphical form. 展开更多
关键词 VIBratioN Trapezoidal Plate Taper Constants Thermal Gradient Aspect ratio Non-Homogeneity thickness Density Frequencies
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Crustal Thickness and Velocity Ratio beneath National Seismic Stations in the Sichuan-Yunnan Area Based on Receiver Function Analysis
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作者 Sun Li Liu Ruifeng +1 位作者 Huang Zhibin Chen Yotdin 《Earthquake Research in China》 2009年第3期340-347,共8页
By using the teleseismic receiver function method, this paper analyzes the crustal thickness and Vp/Vs ratios beneath the 4 National seismic stations (KMI, TNC, CD2 and PZH) in the Sichuan-Yunnan area. This study gi... By using the teleseismic receiver function method, this paper analyzes the crustal thickness and Vp/Vs ratios beneath the 4 National seismic stations (KMI, TNC, CD2 and PZH) in the Sichuan-Yunnan area. This study gives the variance of Moho depths and velocity ratios of the 4 stations in different directions. The results show that the Moho depth beneath the Kunming station is around 50km, and the vdocity ratio varies between 1.62 and 1.69. The thickness of crust and the velocity ratio do not change much with the direction. The crust beneath Tengchong station shows clear directivity, being 40.7km thick in the northeast and 49.7km thick in the southeast. The difference of the Vp/Vs values is remarkable between the two directions, reaching 0.2. The Chengdu station also has shallow Moho, about 40km, but is 8km deeper in the northeast and southwest and the vdocity ratio has a change of 0.13 between the two directions. The crust beneath the Panzhihua station is stable. In all directions, the Moho depth is around 60km and the Vp/Vs ratio doesn't change significantly. 展开更多
关键词 Receiver function MOHO thickness of crust Velocity ratio
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The Crustal Thickness and Poissons Ratio Distribution in Guangdong and Its Adjacent Areas
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作者 Shen Yusong Kang Ying Xu Guoming 《Earthquake Research in China》 CSCD 2016年第1期108-118,共11页
Based on the teleseismic waveform data recorded by 82 permanent broadband stations in Guangdong Province and its adjacent areas including Fujian, Jiangxi, Hunan, Guangxi, Hainan and Taiwan, we calculate body wave rece... Based on the teleseismic waveform data recorded by 82 permanent broadband stations in Guangdong Province and its adjacent areas including Fujian, Jiangxi, Hunan, Guangxi, Hainan and Taiwan, we calculate body wave receiver functions under all stations, and obtain the crustal thickness and average Poisson's ratio beneath all stations by the H-K stacking-search method of receiver function. The results show that the crustal thickness with an average thickness of 29. 5km in Guangdong Province and its adjacent areas ranges between 26. 8km and 33. 6kin and gradually thins from northwest to southeast. The crustal thickness in the Zhujiang Delta, western Guangdong, Nanning and Nan'ao areas is relatively thinner and ranges between 25. 0km and 28. 0km. The minimum crustal thickness is about 26km beneath Wengtian, Hainan and the Zhanjiang zone and Shangchuan Island in Guangdong. The crustal thickness in the zones of Mingxi, Fujian and Yongzhou, Hunan is thicker and varies between 31.0km and 34.0km. The distribution of Poisson's ratio in our study region ranges between 0.20 and 0. 29. Poisson's ratios in Southeast Hainan, the coastal areas of East Guangdong and West Fujian and the South Jiangxi have distinctly higher values than in others. It suggests that the various geothermal fields located in these areas have high heat flow values. The distribution of crustal thickness and Poisson's ratio has an obvious block feature and may be related to the distribution of faults and historical earthquakes. 展开更多
关键词 Receiver function Crustal thickness Poisson's ratio
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Effects of Film Thickness and Ar/O2 Ratio on Resistive Switching Characteristics of HfOx-Based Resistive-Switching Random Access Memories
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作者 郭婷婷 谭婷婷 刘正堂 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第1期125-128,共4页
Cu/HfOx/n^+Si devices are fabricated to investigate the influence of technological parameters including film thickness and Ar/02 ratio on the resistive switching (RS) characteristics of HfOx films, in terms of swit... Cu/HfOx/n^+Si devices are fabricated to investigate the influence of technological parameters including film thickness and Ar/02 ratio on the resistive switching (RS) characteristics of HfOx films, in terms of switch ratio, endurance properties, retention time and multilevel storage. It is revealed that the RS characteristics show strong dependence on technological parameters mainly by altering the defects (oxygen vacancies) in the film. The sample with thickness of 2Onto and Ar/O2 ratio of 12:3 exhibits the best RS behavior with the potential of multilevel storage. The conduction mechanism of all the films is interpreted based on the filamentary model. 展开更多
关键词 Effects of Film thickness and Ar/O2 ratio on Resistive Switching Characteristics of HfOx-Based Resistive-Switching Random Access Memories
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Characterization of the Crustal Thickness and Poisson's Ratio of the Binchuan Region
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作者 Deng Jiamei Jin Mingpei +4 位作者 Chen Jia Gao Qiong Zhang Huaying Wang Jun Ye Beng 《Earthquake Research in China》 CSCD 2017年第1期79-89,共11页
This paper presents the changes of crust thickness and Poisson's ratios distribution in the Binchuan region, where the first air-gun transmitting station and it's a small dense array were deployed. From September 20... This paper presents the changes of crust thickness and Poisson's ratios distribution in the Binchuan region, where the first air-gun transmitting station and it's a small dense array were deployed. From September 2011 to January 2014, more than 239 teleseismic events of M≥ 6.0 were recorded in 16 stations in the Binchuan region. Their P-wave receiver functions were analyzed respectively. The high spatial resolution result shows that the average crust thickness of Binchuan region is 45.3km, it follows the rule of "deeper in the north and east part, shallower in the south and west part. " The deepest region is in Xiaoyindian Station; the crust thickness is 47.9km; the shallowest region is in Paiying Station, it has the thickness of 42. lkm. It shows that the deeper Moho surface nearby the Chenghai fault and shallower nearby the Honghe fault; the isoline distribution of thickness changes greatly nearby the Chenghai fault and slowly nearby the Honghe fault. From the distribution of Poisson's ratios, it is unevenly in the study area with a great difference from the north part to the south part, which shows a characteristic of "lower in the north, higher in the south". The Poisson's ratio nearby the Honghe fault is medium too high ( 0. 26 ≤ σ≤0. 29 ) ; lower nearby the Chenghai fault ( ≤0. 26). This paper concludes the possible reason of different characteristic between Poisson's ratio and crust thickness is thicker in the upper crust in the Binchuan region. 展开更多
关键词 Crustal thickness Poisson's ratio Receiver function The Binchuan region
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