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A novel method for simulating nuclear explosion with chemical explosion to form an approximate plane wave: Field test and numerical simulation 被引量:1
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作者 Wei Ming Xiaojie Yang +3 位作者 Yadong Mao Xiang Wang Manchao He Zhigang Tao 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2137-2153,共17页
A nuclear explosion in the rock mass medium can produce strong shock waves,seismic shocks,and other destructive effects,which can cause extreme damage to the underground protection infrastructures.With the increase in... A nuclear explosion in the rock mass medium can produce strong shock waves,seismic shocks,and other destructive effects,which can cause extreme damage to the underground protection infrastructures.With the increase in nuclear explosion power,underground protection engineering enabled by explosion-proof impact theory and technology ushered in a new challenge.This paper proposes to simulate nuclear explosion tests with on-site chemical explosion tests in the form of multi-hole explosions.First,the mechanism of using multi-hole simultaneous blasting to simulate a nuclear explosion to generate approximate plane waves was analyzed.The plane pressure curve at the vault of the underground protective tunnel under the action of the multi-hole simultaneous blasting was then obtained using the impact test in the rock mass at the site.According to the peak pressure at the vault plane,it was divided into three regions:the stress superposition region,the superposition region after surface reflection,and the approximate plane stress wave zone.A numerical simulation approach was developed using PFC and FLAC to study the peak particle velocity in the surrounding rock of the underground protective cave under the action of multi-hole blasting.The time-history curves of pressure and peak pressure partition obtained by the on-site multi-hole simultaneous blasting test and numerical simulation were compared and analyzed,to verify the correctness and rationality of the formation of an approximate plane wave in the simulated nuclear explosion.This comparison and analysis also provided a theoretical foundation and some research ideas for the ensuing study on the impact of a nuclear explosion. 展开更多
关键词 Approximate plane wave Multi-hole simultaneous blasting Chemical explosion Nuclear explosion Pressure sensor inclusion
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Subplanes of PG( 2, q 3 ) and the Ruled Varieties V 2 5 of PG( 6,q )
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作者 Rita Vincenti 《Open Journal of Discrete Mathematics》 2024年第2期16-27,共12页
In this note we study subplanes of order q of the projective plane Π=PG( 2, q 3 ) and the ruled varieties V 2 5 of Σ=PG( 6,q ) using the spatial representation of Π in Σ, by fixing a hyperplane Σ ′ with a regula... In this note we study subplanes of order q of the projective plane Π=PG( 2, q 3 ) and the ruled varieties V 2 5 of Σ=PG( 6,q ) using the spatial representation of Π in Σ, by fixing a hyperplane Σ ′ with a regular spread of planes. First are shown some configurations of the affine q-subplanes. Then to prove that a variety V 2 5 of Σ represents a non-affine subplane of order q of Π, after having shown basic incidence properties of it, such a variety V 2 5 is constructed by choosing appropriately the two directrix curves in two complementary subspaces of Σ. The result can be translated into further incidence properties of the affine points of V 2 5 . Then a maximal bundle of varieties V 2 5 having in common one directrix cubic curve is constructed. 展开更多
关键词 Finite Geometry Translation planes SPREADS VARIETIES
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THE NONLINEAR STABILITY OF PLANE PARALLEL SHEAR FLOWS WITH RESPECT TO TILTED PERTURBATIONS
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作者 许兰喜 关芳芳 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期1036-1045,共10页
The nonlinear stability of plane parallel shear flows with respect to tilted perturbations is studied by energy methods.Tilted perturbation refers to the fact that perturbations form an angleθ∈(0,π/2)with the direc... The nonlinear stability of plane parallel shear flows with respect to tilted perturbations is studied by energy methods.Tilted perturbation refers to the fact that perturbations form an angleθ∈(0,π/2)with the direction of the basic flows.By defining an energy functional,it is proven that plane parallel shear flows are unconditionally nonlinearly exponentially stable for tilted streamwise perturbation when the Reynolds number is below a certain critical value and the boundary conditions are either rigid or stress-free.In the case of stress-free boundaries,by taking advantage of the poloidal-toroidal decomposition of a solenoidal field to define energy functionals,it can be even shown that plane parallel shear flows are unconditionally nonlinearly exponentially stable for all Reynolds numbers,where the tilted perturbation can be either spanwise or streamwise. 展开更多
关键词 plane parallel shear flows energy method energy functional nonlinear stability Reynolds number
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Nonlinear constitutive models of rock structural plane and their applications
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作者 Wenlin Feng Shuangjian Niu +1 位作者 Chunsheng Qiao Dujian Zou 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期790-806,共17页
Structural planes play an important role in controlling the stability of rock engineering,and the influence of structural planes should be considered in the design and construction process of rock engineering.In this ... Structural planes play an important role in controlling the stability of rock engineering,and the influence of structural planes should be considered in the design and construction process of rock engineering.In this paper,mechanical properties,constitutive theory,and numerical application of structural plane are studied by a combination method of laboratory tests,theoretical derivation,and program development.The test results reveal the change laws of various mechanical parameters under different roughness and normal stress.At the pre-peak stage,a non-stationary model of shear stiffness is established,and threedimensional empirical prediction models for initial shear stiffness and residual stage roughness are proposed.The nonlinear constitutive models are established based on elasto-plastic mechanics,and the algorithms of the models are developed based on the return mapping algorithm.According to a large number of statistical analysis results,empirical prediction models are proposed for model parameters expressed by structural plane characteristic parameters.Finally,the discrete element method(DEM)is chosen to embed the constitutive models for practical application.The running programs of the constitutive models have been compiled into the discrete element model library.The comparison results between the proposed model and the Mohr-Coulomb slip model show that the proposed model can better describe nonlinear changes at different stages,and the predicted shear strength,peak strain and shear stiffness are closer to the test results.The research results of the paper are conducive to the accurate evaluation of structural plane in rock engineering. 展开更多
关键词 Structural plane Engineering stability ROUGHNESS Normal stress Elasto-plastic constitutive model Discrete element method
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Semi-analytical solution for mechanical analysis of tunnels crossing strike-slip fault zone considering nonuniform fault displacement and uncertain fault plane position
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作者 YANG Heng-hong WANG Ming-nian +1 位作者 YU Li ZHANG Xiao 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期2116-2136,共21页
The tunnel subjected to strike-slip fault dislocation exhibits severe and catastrophic damage.The existing analysis models frequently assume uniform fault displacement and fixed fault plane position.In contrast,post-e... The tunnel subjected to strike-slip fault dislocation exhibits severe and catastrophic damage.The existing analysis models frequently assume uniform fault displacement and fixed fault plane position.In contrast,post-earthquake observations indicate that the displacement near the fault zone is typically nonuniform,and the fault plane position is uncertain.In this study,we first established a series of improved governing equations to analyze the mechanical response of tunnels under strike-slip fault dislocation.The proposed methodology incorporated key factors such as nonuniform fault displacement and uncertain fault plane position into the governing equations,thereby significantly enhancing the applicability range and accuracy of the model.In contrast to previous analytical models,the maximum computational error has decreased from 57.1%to 1.1%.Subsequently,we conducted a rigorous validation of the proposed methodology by undertaking a comparative analysis with a 3D finite element numerical model,and the results from both approaches exhibited a high degree of qualitative and quantitative agreement with a maximum error of 9.9%.Finally,the proposed methodology was utilized to perform a parametric analysis to explore the effects of various parameters,such as fault displacement,fault zone width,fault zone strength,the ratio of maximum fault displacement of the hanging wall to the footwall,and fault plane position,on the response of tunnels subjected to strike-slip fault dislocation.The findings indicate a progressive increase in the peak internal forces of the tunnel with the rise in fault displacement and fault zone strength.Conversely,an augmentation in fault zone width is found to contribute to a decrease in the peak internal forces.For example,for a fault zone width of 10 m,the peak values of bending moment,shear force,and axial force are approximately 46.9%,102.4%,and 28.7% higher,respectively,compared to those observed for a fault zone width of 50 m.Furthermore,the position of the peak internal forces is influenced by variations in the ratio of maximum fault displacement of the hanging wall to footwall and the fault plane location,while the peak values of shear force and axial force always align with the fault plane.The maximum peak internal forces are observed when the footwall exclusively bears the entirety of the fault displacement,corresponding to a ratio of 0:1.The peak values of bending moment,shear force,and axial force for the ratio of 0:1 amount to approximately 123.8%,148.6%,and 111.1% of those for the ratio of 0.5:0.5,respectively. 展开更多
关键词 strike-slip fault tunnel engineering semi-analytical solution fault zone width nonuniform fault displacement uncertain fault plane position
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An 8-Node Plane Hybrid Element for StructuralMechanics Problems Based on the Hellinger-Reissner Variational Principle
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作者 Haonan Li WeiWang +1 位作者 Quan Shen Linquan Yao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1277-1299,共23页
The finite element method (FEM) plays a valuable role in computer modeling and is beneficial to the mechanicaldesign of various structural parts. However, the elements produced by conventional FEM are easily inaccurat... The finite element method (FEM) plays a valuable role in computer modeling and is beneficial to the mechanicaldesign of various structural parts. However, the elements produced by conventional FEM are easily inaccurate andunstable when applied. Therefore, developing new elements within the framework of the generalized variationalprinciple is of great significance. In this paper, an 8-node plane hybrid finite element with 15 parameters (PHQ8-15β) is developed for structural mechanics problems based on the Hellinger-Reissner variational principle.According to the design principle of Pian, 15 unknown parameters are adopted in the selection of stress modes toavoid the zero energy modes.Meanwhile, the stress functions within each element satisfy both the equilibrium andthe compatibility relations of plane stress problems. Subsequently, numerical examples are presented to illustrate theeffectiveness and robustness of the proposed finite element. Numerical results show that various common lockingbehaviors of plane elements can be overcome. The PH-Q8-15β element has excellent performance in all benchmarkproblems, especially for structures with varying cross sections. Furthermore, in bending problems, the reasonablemesh shape of the new element for curved edge structures is analyzed in detail, which can be a useful means toimprove numerical accuracy. 展开更多
关键词 8-node plane hybrid element Hellinger-Reissner variational principle locking behaviors structural mechanics problems
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Regulating the inner Helmholtz plane structure at the electrolyte-electrode interface for highly reversible aqueous Zn batteries
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作者 Jianghe Liu Sanlue Hu +6 位作者 Hexin Guo Guobin Zhang Wen Liu Jianwei Zhao Shenhua Song Cuiping Han Baohua Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期57-67,I0002,共12页
The development of aqueous Zn batteries is limited by parasitic water reactions,corrosion,and dendrite growth.To address these challenges,an inner Helmholtz plane(IHP)regulation method is proposed by employing low-cos... The development of aqueous Zn batteries is limited by parasitic water reactions,corrosion,and dendrite growth.To address these challenges,an inner Helmholtz plane(IHP)regulation method is proposed by employing low-cost,non-toxic maltitol as the electrolyte additive.The preferential adsorption behavior of maltitol can expel the water from the inner Helmholtz plane,and thus hinder the immediate contact between Zn metal and H_(2)O.Meanwhile,strong interaction between maltitol and H_(2)O molecules can restrain the activity of H_(2)O.Besides,the"IHP adsorption effect"along with the low LUMO energy level of maltitol-CF_(3)SO_(3)^(-)can promote the in-situ formation of an organic-inorganic complex solid electrolyte interface(SEI)layer.As a result,the hydrogen/oxygen evolution side reaction,corrosion,and dendrites issues are effectively suppressed,thereby leading to highly reversible and dendrite-free Zn plating/stripping.The Zn‖I_(2)battery with hybrid electrolytes also demonstrates high electrochemical performance and ultralong cycling stability,showing a capacity retention of 75%over 20000 charge-discharge cycles at a large current density of 5 A g^(-1).In addition,the capacity of the device has almost no obvious decay over20000 cycles even at-30℃.This work offers a successful electrolyte regulation strategy via the IHP adsorption effect to design electrolytes for high-performance rechargeable Zn-ion batteries. 展开更多
关键词 Inner Helmholtz plane Adsorption effect Dendrite suppression SEI layer Zn||I_(2)battery
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Review on dynamic analysis of road pavements under moving vehicles and plane strain conditions
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作者 Edmond V.Muho Niki D.Beskou 《Journal of Road Engineering》 2024年第1期54-68,共15页
This paper reviews works on the dynamic analysis of flexible and rigid pavements under moving vehicles on the basis of continuum-based plane strain models and linear theories.The purpose of this review is to provide i... This paper reviews works on the dynamic analysis of flexible and rigid pavements under moving vehicles on the basis of continuum-based plane strain models and linear theories.The purpose of this review is to provide in-formation about the existing works on the subject,critically discuss them and make suggestions for further research.The reviewed papers are presented on the basis of the various models for pavement-vehicle systems and the various methods for dynamically analyzing these systems.Flexible pavements are modeled by a homogeneous or layered half-plane with isotropic or anisotropic and linear elastic,viscoelastic or poroelastic material behavior.Rigid pavements are modeled by a beam or plate on a homogeneous or layered half-plane with material properties like the ones for flexible pavements.The vehicles are modeled as concentrated or distributed over a finite area loads moving with constant or time dependent speed.The above pavement-vehicle models are dynamically analyzed by analytical,analytical/numerical or purely numerical methods working in the time or frequency domain.Representative examples are presented to illustrate the models and methods of analysis,demonstrate their merits and assess the effects of the various parameters on pavement response.The paper closes with con-clusions and suggestions for further research in the area.The significance of this research effort has to do with the presentation of the existing literature on the subject in a critical and easy to understand way with the aid of representative examples and the identification of new research areas. 展开更多
关键词 Flexible pavements Rigid pavements Moving vehicles plane strain models Dynamic analysis
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Study on the Evolution of Plane Shape of Guangfu Ancestral Hall Buildings and the Construction of Type Genealogy in the Ming and Qing Dynasties
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作者 Yanming Chen Sharul Azim Sharudin Rui Chen 《Journal of Architectural Research and Development》 2024年第1期1-7,共7页
This paper studies the clan temples in four periods,namely,the development period(early Ming Dynasty and before),the shaping period(mid-Ming Dynasty to early Qing Dynasty),the maturity period(mid-Qing Dynasty),and the... This paper studies the clan temples in four periods,namely,the development period(early Ming Dynasty and before),the shaping period(mid-Ming Dynasty to early Qing Dynasty),the maturity period(mid-Qing Dynasty),and the programmed period(late Qing Dynasty),analyzes and summarizes their prototypical planform features and attempts to summarize and construct a genealogy of the architectural characteristics of the plane shape of clan temples.During the Ming and Qing dynasties,Guangfu ancestral halls in general showed a journey of development from a centripetal-single-linear-multi-linear-grid pattern,forming the unique Guangsanlu classic pattern in the Guangfu area. 展开更多
关键词 Guangfu clan Ancestral halls plane shape GENEALOGY
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Tunnel effect of fractal fault and transient S-wave velocity rupture (TSVR) of in-plane shear fault 被引量:3
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作者 李世愚 陈运泰 《Acta Seismologica Sinica(English Edition)》 CSCD 1999年第1期19-25,共7页
Transient S wave velocity rupture (TSVR) means the velocity of fault rupture propagation is between S wave velocity α and P wave velocity β . Its existing in the rupture of in plane ( i.e . strike slip... Transient S wave velocity rupture (TSVR) means the velocity of fault rupture propagation is between S wave velocity α and P wave velocity β . Its existing in the rupture of in plane ( i.e . strike slip) fault has been proved, but in 2 dimensional classical model, there are two difficulties in transient S wave velocity rupture, i.e ., initialization difficulty and divergence difficulty in interpreting the realization of TSVR. The initialization difficulty means, when v ↑ v R (Rayleigh wave velocity), the dynamic stress strength factor K 2(t) →+0, and changes from positive into negative in the interval ( v R, β ). How v transit the forbidden of ( v R, β )? The divergence difficulty means K 2(t) →+∞ when v ↓ β . Here we introduce the concept of fractal and tunnel effect that exist everywhere in fault. The structure of all the faults is fractal with multiple cracks. The velocity of fault rupture is differentiate of the length of the fault respect to time, so the rupture velocity is also fractal. The tunnel effect means the dynamic rupture crosses over the interval of the cracks, and the coalescence of the intervals is slower than the propagation of disturbance. Suppose the area of earthquake nucleation is critical or sub critical propagation everywhere, the arriving of disturbance triggers or accelerates the propagation of cracks tip at once, and the observation system cannot distinguish the front of disturbance and the tip of fracture. Then the speed of disturbance may be identified as fracture velocity, and the phenomenon of TSVR appears, which is an apparent velocity. The real reason of apparent velocity is that the mathematics model of shear rupture is simplified of complex process originally. The dual character of rupture velocity means that the apparent velocity of fault and the real velocity of micro crack extending, which are different in physics, but are unified in rupture criterion. Introducing the above mentioned concept to the calculation of K 2 (t) , the difficulty of initialization can be overcome, and the integral equation of triggering the initialization of TSVR is given quantitatively. By solving this integral equation, the lower limit of TSVR is 1.105 3 β , not β , and the divergence difficulty is overcome. TSVR is unstable solution, and may degenerate to sub Rayleigh wave velocity rupture immediately where the non critical condition can be measured. The results of this paper show that the initialization and continuum depends on the condition of earthquake nucleation in seismogenic area. 展开更多
关键词 dynamics of earthquake rupture in plane shear fault fractal transient S wave velocity RUPTURE
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Erector Spinae Plane Block Combined with Serratus Anterior Plane Block Versus Thoracic Paravertebral Block for Postoperative Analgesia and Recovery After Thoracoscopic Surgery:A Randomized Controlled Non-inferiority Clinical Trial 被引量:2
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作者 Xuan MO Tao JIANG +1 位作者 Han WANG Yi ZHANG 《Current Medical Science》 SCIE CAS 2023年第3期615-622,共8页
Objective This study aimed to compare the postoperative analgesia and recovery of ultrasound-guided erector spinae plane block combined with serratus anterior plane block(ESPB combined with SAPB)versus thoracic parave... Objective This study aimed to compare the postoperative analgesia and recovery of ultrasound-guided erector spinae plane block combined with serratus anterior plane block(ESPB combined with SAPB)versus thoracic paravertebral block(PVB)after thoracoscopic surgery.Methods Ninety-two patients who underwent video-assisted thoracoscopic surgery(VATS)were randomly divided into group S(n=46)and group P(n=46).After anesthesia induction,the same anesthesiologist performed ultrasound-guided ESPB at T5 and T7 levels combined with SAPB at the level of the fifth rib in the midaxillary line in group S and ultrasound-guided PVB at T5 and T7 levels in group P.Patients in both groups were given 40 mL of 0.4%ropivacaine.Eighty-six patients completed the study(group S,n=44;group P,n=42).The morphine consumption,visual analogue scale(VAS)scores at rest and coughing,and frequency of remedial analgesia were recorded at 1,2,4,8,and 24 h postoperatively.Pulmonary function parameters were recorded at 1,4,and 24 h postoperatively,and the quality of recovery(QoR)-15 score at 24 h postoperatively.The adverse effects,duration of chest tube drainage and length of stay were also recorded.Results The morphine consumption at postoperative 4 and 8 h and the incidence of ipsilateral shoulder pain(ISP)were significantly lower in group S than in group P.The QoR-15 questionnaire score at postoperative 24 h was significantly lower in group P than in group S(P<0.05).The morphine consumption was lower at 24 h postoperatively in group S than in group P,with no significant difference found yet.The morphine consumption at other observed times,VAS scores,pulmonary function parameters,frequency of remedial analgesia,duration of chest tube drainage,length of stay,and incidence of other adverse events were comparable between group S and group P.Conclusion Ultrasound-guided ESPB combined with SAPB is non-inferior to PVB in terms of morphine consumption at postoperative 24 h and postoperative recovery.But,this approach can significantly reduce morphine consumption in the early postoperative period(0–8 h)after thoracoscopy with lower incidence of ISP.It is a simpler and safer operation. 展开更多
关键词 erector spinae plane block serratus anterior plane block thoracic paravertebral block postoperative analgesia postoperative recovery
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A New Approach to Plane Failure of Rock Slope Stability Based on Water Flow Velocity in Discontinuities for the Latian Dam Reservoir Landslide 被引量:3
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作者 Morteza AHMADI Majid ESLAMI 《Journal of Mountain Science》 SCIE CSCD 2011年第2期124-130,共7页
The stability of slopes is always of great concern in the field of rock engineering. The geometry and orientation of pre-existing discontinuities show a larger impact on the behavior of slopes that is often used to de... The stability of slopes is always of great concern in the field of rock engineering. The geometry and orientation of pre-existing discontinuities show a larger impact on the behavior of slopes that is often used to describe the measurement of the steepness, incline, gradient, or grade of a straight line. One of the structurally controlled modes of failure in jointed rock slopes is plane failure. There are numerous analytical methods for the rock slope stability including limit equilibrium, stress analysis and stereographic methods. The limiting equilibrium methods for slopes under various conditions against plane failure have been previously proposed by several investigators. However, these methods do not involve water pressure on sliding surfaces assessments due to water velocity and have not yet been validated by case study results. This paper has tried to explore the effects of forces due to water pressure on discontinuity surfaces in plane failure through applying the improved equations. It has studied the effect of water flow velocity on sliding surfaces in safety factor, as well. New equations for considering water velocity (fluid dynamics) are presented. To check the validity of the suggested equations, safety factor for a case study has been determined. Results show that velocity of water flow had significant effect on the amount of safety factor. Also, the suggested equations have higher validity rate compared to the current equations. 展开更多
关键词 水库滑坡 水流速度 边坡稳定性 飞机故障 不连续性 法平面 极限平衡方法 大坝
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THE NEW METHOD OF SOLVING VELOCITY CORRELATION FUNCTIONS AND APPLICATION TO THE PLANE TURBULENT WAKE
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作者 林建忠 黄永念 周培源 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1993年第2期102-109,共8页
The results of plane turbulent wake given by Chou Peiyuan are considered as the first order ap- proximation and put into the equations of turbulent fluctuation.The equations are solved numerically within the range of ... The results of plane turbulent wake given by Chou Peiyuan are considered as the first order ap- proximation and put into the equations of turbulent fluctuation.The equations are solved numerically within the range of micro-scale by means of spectrum method.The double,triple and quadruple fluctuating velocity correlations are obtained by computation.They are in good agreement with experimental results. 展开更多
关键词 higher order correlation SELF-PRESERVATION successive iterations plane turbulent wake numerical computation
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Analytical investigation on mean and turbulent velocity fields of a plane jet
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作者 米建春 冯宝平 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第7期279-285,共7页
This paper analyses the downstream developments of the mean and the turbulent velocity fields of a plane jet. Based on the conservation of mass and the conservation of momentum, the mean-velocity half width (reflecti... This paper analyses the downstream developments of the mean and the turbulent velocity fields of a plane jet. Based on the conservation of mass and the conservation of momentum, the mean-velocity half width (reflecting the jet spread rate) and the relative mass flow rate (jet entrainment) are related to the decay rate of the centreline mean velocity. These relations are not subject to self-preservation. Both analytical and experimental results suggest that the jet spread rate (K1) and the entrainment rate (K3) (and thus the decay rate K2) can be well estimated from the centreline velocity, i.e., K1 ≈ 0.6K2 and K3 ∝K2. The effect of initial mean velocity and RMS velocity profiles on the downstream mean velocity field appears to be embodied in the constants K1 K2 and K3. The analytical relationship for the self-preserving Reynolds shear stress, obtained for the first time, works well. 展开更多
关键词 turbulent plane jet momentum conservation Reynolds shear stress
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Analyses and identifications of quantitative trait loci and candidate genes controlling mesocotyl elongation in rice 被引量:1
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作者 ZHANG Xi-juan LAI Yong-cai +11 位作者 MENG Ying TANG Ao DONG Wen-jun LIU You-hong LIU Kai WANG Li-zhi YANG Xian-li WANG Wen-long DING Guo-hua JIANG Hui REN Yang JIANG Shu-kun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第2期325-340,共16页
Rice direct seeding has the significant potential to save labor and water,conserve environmental resources,and reduce greenhouse gas emissions tremendously.Therefore,rice direct seeding is becoming the major cultivati... Rice direct seeding has the significant potential to save labor and water,conserve environmental resources,and reduce greenhouse gas emissions tremendously.Therefore,rice direct seeding is becoming the major cultivation technology applied to rice production in many countries.Identifying and utilizing genes controlling mesocotyl elongation is an effective approach to accelerate breeding procedures and meet the requirements for direct-seeded rice(DSR) production.This study used a permanent mapping population with 144 recombinant inbred lines(RILs) and 2 828 bin-markers to detect quantitative trait loci(QTLs) associated with mesocotyl length in 2019 and 2020.The mesocotyl lengths of the rice RILs and their parents,Lijiangxintuanheigu(LTH) and Shennong 265(SN265),were measured in a growth chamber at 30°C in a dark environment.A total of 16 QTLs for mesocotyl length were identified on chromosomes 1(2),2(4),3(2),4,5,6,7,9,11(2),and 12.Seven of these QTLs,including qML1a,qML1b,qML2d,qML3a,qML3b,qML5,and qML11b,were reproducibly detected in both years via the interval mapping method.The major QTL,qML3a,was reidentified in two years via the composite interval mapping method.A total of 10 to 413 annotated genes for each QTL were identified in their smallest genetic intervals of 37.69 kb to 2.78 Mb,respectively.Thirteen predicted genes within a relatively small genetic interval(88.18 kb) of the major mesocotyl elongation QTL,qML3a,were more thoroughly analyzed.Finally,the coding DNA sequence variations among SN265,LTH,and Nipponbare indicated that the LOC_Os03g50550 gene was the strongest candidate gene for the qML3a QTL controlling the mesocotyl elongation.This LOC_Os03g50550 gene encodes a mitogen-activated protein kinase.Relative gene expression analysis using qRT-RCR further revealed that the expression levels of the LOC_Os03g50550 gene in the mesocotyl of LTH were significantly lower than in the mesocotyl of SN265.In conclusion,these results further strengthen our knowledge about rice’s genetic mechanisms of mesocotyl elongation.This investigation’s discoveries will help to accelerate breeding programs for new DSR variety development. 展开更多
关键词 japonica rice direct-seeded rice(DSR) mesocotyl elongation quantitative trait loci candidate gene
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Mass-front velocity of dry granular flows influenced by the angle of the slope to the runout plane and particle size gradation 被引量:17
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作者 FAN Xiao-yi TIAN Shu-jun ZHANG You-yi 《Journal of Mountain Science》 SCIE CSCD 2016年第2期234-245,共12页
The mass-front velocities of granular flows results from the joint action of particle size gradations and the underlying surfaces.However,because of the complexity of friction during flow movement,details such as the ... The mass-front velocities of granular flows results from the joint action of particle size gradations and the underlying surfaces.However,because of the complexity of friction during flow movement,details such as the slope-toe impedance effects and momentum-transfer mechanisms have not been completely explained by theoretical analyses,numerical simulations,or field investigations.To study the mass-front velocity of dry granular flows influenced by the angle of the slope to the runout plane and particle size gradations we conducted model experiments that recorded the motion of rapid and long-runout rockslides or avalanches.Flume tests were conducted using slope angles of 25°,35°,45°,and 55° and three particle size gradations.The resulting mass-front motions consisted of three stages:acceleration,velocity maintenance,and deceleration.The existing methods of velocity prediction could not explain the slowing effect of the slope toe or the momentum-transfer steady velocity stage.When the slope angle increased from 25° to 55°,the mass-front velocities dropped significantly to between 44.4% and59.6% of the peak velocities and energy lossesincreased from 69.1% to 83.7% of the initial,respectively.The velocity maintenance stages occurred after the slope-toe and mass-front velocity fluctuations.During this stage,travel distances increased as the angles increased,but the average velocity was greatest at 45°.At a slope angle of 45°,as the median particle size increased,energy loss around the slope toe decreased,the efficiency of momentum transfer increased,and the distance of the velocity maintenance stage increased.We presented an improved average velocity formula for granular flow and a geometrical model of the energy along the flow line. 展开更多
关键词 传递速度 颗粒级配 边坡角 颗粒流 质量 平面 摆动 动量传递
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Crystal plane induced in-situ electrochemical activation of manganese-based cathode enable long-term aqueous zinc-ion batteries 被引量:1
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作者 Yuxin Gao Jiang Zhou +6 位作者 Liping Qin Zhenming Xu Zhexuan Liu Liangbing Wang Xinxin Cao Guozhao Fang Shuquan Liang 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第5期1429-1436,共8页
Rapid capacity decay and sluggish reaction kinetics are major barriers hindering the applications of manganese-based cathode materials for aqueous zinc-ion batteries.Herein,the effects of crystal plane on the in-situ ... Rapid capacity decay and sluggish reaction kinetics are major barriers hindering the applications of manganese-based cathode materials for aqueous zinc-ion batteries.Herein,the effects of crystal plane on the in-situ transformation behavior and electrochemical performance of manganese-based cathode is discussed.A comprehensive discussion manifests that the exposed(100)crystal plane is beneficial to the phase transformation from tunnel-structured MnO_(2) to layer-structured ZnMn_(3)O_(7)·3H_(2)O,which plays a critical role for the high reactivity,high capacity,fast diffusion kinetics and long cycling stability.Additionally,a two-stage zinc storage mechanism can be demonstrated,involving continuous activation reaction and phase transition reaction.As expected,it exhibits a high capacity of 275 mAh g^(-1)at 100 mA g^(-1),a superior durability over 1000 cycles and good rate capability.This study may open new windows toward developing advanced cathodes for ZIBs,and facilitate the applications of ZIBs in large-scale energy storage system. 展开更多
关键词 Crystal plane Electrochemical activation Phase transition reaction Cycling stability Zinc-ion batteries
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Anti-Corrosion and Reconstruction of Surface Crystal Plane for Zn Anodes by an Advanced Metal Passivation Technique 被引量:1
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作者 Si Liu Hongxin Lin +2 位作者 Qianqian Song Jian Zhu Changbao Zhu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第4期166-172,共7页
For the aqueous Zn-ion battery,dendrite formation,corrosion,and interfacial parasitic reactions are major issues,which greatly inhibits their practical application.How to develop a method of Zn construction or treatme... For the aqueous Zn-ion battery,dendrite formation,corrosion,and interfacial parasitic reactions are major issues,which greatly inhibits their practical application.How to develop a method of Zn construction or treatment to solve these issues for Zn anodes are still great challenges.Herein,a simple and cheap metal passivation technique is proposed for Zn anodes from a corrosion science perspective.Similar to the metal anticorrosion engineering,the formed interfacial protective layer in a chemical way can sufficiently solve the corrosion issues.Furthermore,the proposed passivity approach can reconstruct Zn surface-preferred crystal planes,exposing more(002)planes and improving surface hydrophilicity,which inhibits the formation of Zn dendrites and hydrogen evolution effectively.As expected,the passivated Zn achieves outstanding cycling life(1914 h)with low voltage polarization(<40 mV).Even at 6 mA cm^(−2) and 3 mA h cm^(−2),it can achieve stable Zn deposition over 460 h.The treated Zn anode coupled with MnO_(2) cathode shows prominently reinforced full batteries service life,making it a potential Zn anode candidate for excellent performance aqueous Zn-ion batteries.The proposed passivation approach provides a guideline for other metal electrodes preparation in various batteries and establishes the connections between corrosion science and batteries. 展开更多
关键词 ANTI-CORROSION aqueous zinc ion battery interfacial protective layer metal passivation technique reconstruction of surface crystal plane
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Analgesic effect of ultrasound-guided bilateral transversus abdominis plane block in laparoscopic gastric cancer 被引量:1
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作者 Ya-Ya Wang Hua-Jun Fu 《World Journal of Gastrointestinal Surgery》 SCIE 2023年第10期2171-2178,共8页
BACKGROUND Postoperative complications are important factors affecting the survival time and quality of life of patients undergoing radical gastrectomy.AIM To investigate and compare the anesthetic effects of intraven... BACKGROUND Postoperative complications are important factors affecting the survival time and quality of life of patients undergoing radical gastrectomy.AIM To investigate and compare the anesthetic effects of intravenous general anesthesia combined with epidural anesthesia or ultrasound-guided bilateral transversus abdominal plane block(TAPB)in gastric cancer patients undergoing laparoscopic radical gastrectomy.METHODS The clinical data of 85 patients who underwent laparoscopic radical gastrectomy in our hospital from December 2020 to January 2023 were retrospectively collected and divided into a TAPB group(n=45)and epidural anesthesia group(n=40)according to the different anesthesia and analgesia programs used.The TAPB group received general anesthesia combined with TAPB,and the epidural anesthesia group received general anesthesia combined with epidural anesthesia.The pain status,cognitive status,intestinal barrier indicators,recovery quality,and incidence of complications were compared between the two groups.RESULTS Compared with the epidural anesthesia group,the TAPB group’s visual analog scale scores were significantly lower 6 h,12 h,24 h and 48 h after surgery(P<0.05).The incidence of postoperative cognitive dysfunction(POCD)in the TAPB group was significantly lower than that in the epidural anesthesia group,and the Mini-mental State Examination score 24 h after surgery was significantly higher in the TAPB group than the epidural anesthesia group(P<0.05).The levels of diamine oxidase and plasma D-lactate were significantly lower in the TAPB group than the epidural anesthesia group 24 h after surgery(P<0.05).The agitation score and the incidence of agitation during recovery were significantly lower in the TAPB group than epidural anesthesia group(P<0.05).The total incidence of postoperative complications in the TAPB group was 4.44%,significantly lower than the 20.00%in the epidural anesthesia group(P<0.05).CONCLUSION Compared with epidural anesthesia combined with general anesthesia,TAPB combined with general anesthesia had a good analgesic effect in laparoscopic radical gastrectomy and can further reduce the incidence of POCD and postoperative complications,improve the levels of intestinal barrier indicators,and improve postoperative recovery quality. 展开更多
关键词 Laparoscopic radical gastrectomy Ultrasound-guided bilateral transversus abdominal plane block Cognitive impairment Intestinal barrier function
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Genetic susceptibility loci of lung cancer are associated with malignant risk of pulmonary nodules and improve malignancy diagnosis based on CEA levels
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作者 Zhi Li Liming Lu +8 位作者 Yibin Deng Amei Zhuo Fengling Hu Wanwen Sun Guitian Huang Linyuan Liu Boqi Rao Jiachun Lu Lei Yang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2023年第5期501-510,共10页
Objective:The heightened prevalence of pulmonary nodules(PN)has escalated its significance as a public health concern.While the precise identification of high-risk PN carriers for malignancy remains an ongoing challen... Objective:The heightened prevalence of pulmonary nodules(PN)has escalated its significance as a public health concern.While the precise identification of high-risk PN carriers for malignancy remains an ongoing challenge,genetic variants hold potentials as determinants of disease susceptibility that can aid in diagnosis.Yet,current understanding of the genetic loci associated with malignant PN(MPN)risk is limited.Methods:A frequency-matched case-control study was performed,comprising 247 MPN cases and 412 benign NP(BNP)controls.We genotyped 11 established susceptibility loci for lung cancer in a Chinese cohort.Loci associated with MPN risk were utilized to compute a polygenic risk score(PRS).This PRS was subsequently incorporated into the diagnostic evaluation of MPNs,with emphasis on serum tumor biomarkers.Results:Loci rs10429489G>A,rs17038564A>G,and rs12265047A>G were identified as being associated with an increased risk of MPNs.The PRS,formulated from the cumulative risk effects of these loci,correlated with the malignant risk of PNs in a dose-dependent fashion.A high PRS was found to amplify the MPN risk by 156%in comparison to a low PRS[odds ratio(OR)=2.56,95%confidence interval(95%CI),1.40−4.67].Notably,the PRS was observed to enhance the diagnostic accuracy of serum carcinoembryonic antigen(CEA)in distinguishing MPNs from BPNs,with diagnostic values rising from 0.716 to 0.861 across low-to high-PRS categories.Further bioinformatics investigations pinpointed rs10429489G>A as an expression quantitative trait locus.Conclusions:Loci rs10429489G>A,rs17038564A>G,and rs12265047A>G contribute to MPN risk and augment the diagnostic precision for MPNs based on serum CEA concentrations. 展开更多
关键词 Pulmonary nodules susceptible loci serum tumor biomarkers polygenic risk score DIAGNOSIS
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