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Reshaping force for deformed casing repairing with hydraulic rolling reshaper and its influencing factors
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作者 Hong-Fei Li Min Luo +2 位作者 Ting-Ting Xu Qiao-Zhen Li Cong-Jian Huang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2745-2757,共13页
Hydraulic rolling reshaper is an advanced reshaping tool to solve the problem of casing deformation,which has been widely used in recent years.When it is used for well repair operation,the reshaping force provided by ... Hydraulic rolling reshaper is an advanced reshaping tool to solve the problem of casing deformation,which has been widely used in recent years.When it is used for well repair operation,the reshaping force provided by ground devices is generally determined by experience.However,too large reshaping force may destroy the deformed casing,and too small reshaping force may also prolong the construction period and affect the repairing effect.In this paper,based on Hertz contact theory and elastic-plastic theory,combined with the process parameters of shaping,and considering the structural characteristics of the deformed casing and reshaper,we propose a mathematical model for calculating the reshaping force required for repairing deformed casing by hydraulic rolling reshaper.Meanwhile,the finite element model and numerical method of hydraulic rolling reshaper repairing deformed casing are established by using the finite element method,and the reliability of the mathematical model is verified by several examples.On this basis,the control variable method is used to investigate the influence of each parameter on the reshaping force,and the influence degree of each parameter is explored by orthogonal simulation test and Pearson correlation analysis.The research results not only provide an important theoretical basis for the prediction of reshaping force in on-site construction,but also provide a reference for the subsequent improvement of the shaping process. 展开更多
关键词 Hydraulic rolling reshaper Reshaping force deformed casing Casing reshaping Hertz contact theory
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The breaking of spin symmetry in the single-particle resonances in deformed nuclei
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作者 Zhen-Yu Zheng Shou-Wan Chen Quan Liu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期237-245,共9页
The exploration of spin symmetry (SS) in nuclear physics has been instrumental in identifying atomic nucleus structures.In this study,we solve the Dirac equation from the relativistic mean field (RMF) in complex momen... The exploration of spin symmetry (SS) in nuclear physics has been instrumental in identifying atomic nucleus structures.In this study,we solve the Dirac equation from the relativistic mean field (RMF) in complex momentum representation.We investigated SS and its breaking in single-particle resonant states within deformed nuclei,with a focus on the illustrative nucleus168Er.This was the initial discovery of a resonant spin doublet in a deformed nucleus,with the expectation of the SS approaching the continuum threshold.With increasing single-particle energy,the splitting of the resonant spin doublets widened significantly.This escalating splitting implies diminishing adherence to the SS,indicating a departure from the expected behavior as the energy levels increase.We also analyzed the width of the resonant states,showing that lower orbital angular momentum resonances possess shorter decay times and that SS is preserved within broad resonant doublets,as opposed to narrow resonant doublets.Comparing the radial density of the upper components for the bound-state and resonant-state doublets,it becomes evident that while SS is well-preserved in the bound states,it deteriorates in the resonant states.The impact of nuclear deformation (β_(2)) on SS was examined,demonstrating that an increase in β_(2) resulted in higher energy and width splitting in the resonant spin doublets,which is attributed to increased component mixing.Furthermore,the sensitivity of spin doublets to various potential parameters such as surface diffuseness (a),radius (R),and depth (Σ0) is discussed,emphasizing the role of these parameters in SS.This study provides valuable insights into the behavior of spin doublets in deformed nuclei and their interplay with the nuclear structure,thereby advancing our understanding of SS in the resonance state. 展开更多
关键词 Spin symmetry Resonant states deformed nuclei Complex-momentum representation
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αDecay in extreme laser fields within a deformed Gamow-like model
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作者 Qiong Xiao Jun-Hao Cheng +3 位作者 Yang-Yang Xu You-Tian Zou Jun-Gang Deng Tong-Pu Yu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期131-144,共14页
In this study, the effect of extreme laser fields on the α decay process of ground-state even–even nuclei was investigated.Using the deformed Gamow-like model, we found that state-of-the-art lasers can cause a sligh... In this study, the effect of extreme laser fields on the α decay process of ground-state even–even nuclei was investigated.Using the deformed Gamow-like model, we found that state-of-the-art lasers can cause a slight change in the α decay penetration probability of most nuclei. In addition, we studied the correlation between the rate of change of the α decay penetration probability and angle between the directions of the laser electric field and α particle emission for different nuclei. Based on this correlation, the average effect of extreme laser fields on the half-life of many nuclei with arbitrary α particle emission angles was calculated. The calculations show that the laser suppression and promotion effects on the α decay penetration probability of the nuclei population with completely random α particle-emission directions are not completely canceled.The remainder led to a change in the average penetration probability of the nuclei. Furthermore, the possibility of achieving a higher average rate of change by altering the spatial shape of the laser is explored. We conclude that circularly polarized lasers may be helpful in future experiments to achieve a more significant average rate of change of the α decay half-life of the nuclei population. 展开更多
关键词 αDecay deformed Gamow-like model HALF-LIVES Extreme laser field Penetration probability
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Mechanical and magnetocaloric adjustable properties of Fe3O4/PET deformed nanoparticle film
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作者 范凤国 段林彤 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期589-595,共7页
The flexibility of nanoparticle films is a topic of rapidly growing interest in both scientific and engineering researches due to their numerous potential applications in a broad range of wearable electronics and biom... The flexibility of nanoparticle films is a topic of rapidly growing interest in both scientific and engineering researches due to their numerous potential applications in a broad range of wearable electronics and biomedical devices.This article presents the elucidation of the properties of nanoparticle films.Here,a flexible film is fabricated based on polyethylene terephthalate(PET)and magnetic iron oxide at the nanoscale using layer-by-layer technology.The 2D thin flexible film material can be bent at different angles from 0°to 360°.With an increase in elastic deformation angles,the magnetocaloric effect of the film gradually increases in the alternating magnetic field.The test results from a vibrating sample magnetometer and a low-frequency impedance analyzer demonstrate that the film has a good magnetic response and anisotropy.The magnetocaloric effect and magnetic induction effect are controlled by deformation,providing a new idea for the application of elastic films.It combines the flexibility of the nanoparticle PET substrate and,in the future,it may be used for skin adhesion for administration and magnetic stimulation control. 展开更多
关键词 nanoparticle film deformation magnetic properties flexible substrates
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水稻矮化并花发育异常突变体dwarf and deformed flower 2(ddf2)的基因定位与候选基因分析 被引量:8
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作者 张玲 郭爽 +5 位作者 汪玲 张天泉 庄慧 龙珏臣 何光华 李云峰 《中国农业科学》 CAS CSCD 北大核心 2015年第10期1873-1881,共9页
【目的】对一个同时导致营养和生殖器官发育异常的水稻突变体进行表型鉴定、基因定位和候选基因分析,为下一步的基因克隆与功能分析奠定基础。【方法】在水稻籼型恢复系602组织培养后代中,发现一个矮化并花发育异常突变体dwarf and defo... 【目的】对一个同时导致营养和生殖器官发育异常的水稻突变体进行表型鉴定、基因定位和候选基因分析,为下一步的基因克隆与功能分析奠定基础。【方法】在水稻籼型恢复系602组织培养后代中,发现一个矮化并花发育异常突变体dwarf and deformed flower 2(ddf2)。抽穗期,以野生型为对照,对ddf2株高、主穗长、节间和功能叶的长宽等性状进行统计分析;同时利用冷冻切片等技术对茎、叶和花器官进行详细的形态和组织学分析。分别以西农1A和中花11为母本,以DDF2/ddf2杂合株系为父本构建2个F2群体进行遗传分析和基因定位,并对候选基因进行实时荧光定量PCR(real-time PCR)分析。【结果】相较于野生型,突变体各节间的长和茎粗均极显著降低,叶片极显著变短、变窄,同时花序也极显著变短。组织细胞学分析发现,突变体大叶脉数目和相邻2个大叶脉之间的小叶脉数都没有明显的变化,但相邻2个大叶脉之间的宽度明显减小,进一步比较2个小叶脉之间的叶肉细胞,发现在突变体中细胞数目和尺寸均显著降低;突变体茎秆维管束的数目与野生型相比没有明显的变化,但统计发现2个大维管束之间基本组织细胞的数量和细胞的大小都显著小于野生型,表明ddf2突变体茎、叶细胞分裂和膨胀都受到了抑制;此外,ddf2突变体的花器官特征发育受到了严重干扰:第一轮外稃顶部弯曲、内稃不同程度退化,第三轮雄蕊器官严重退化,部分甚至转化为雌蕊状器官,另外部分ddf2小穗的护颖过度发育,转变成稃片状,一些小穗还表现分生组织确定性的丢失,发育出2个以上的小花。遗传分析表明该突变性状受1对隐性基因控制。利用中花11/ddf2的1 024株F2分离群体,最终将DDF2精细定位在第11染色体短臂近着丝粒位置处,位于insertion/deletion(in/del)标记S-11和S-14之间,遗传距离分别为0.049和0.098c M,物理距离为90.295 kb,并与标记S-24共分离。分析定位区间的基因,发现共有MSU注释基因12个,其中一个编码Sec3_C蛋白的LOC_Os11g17600内部包含共分离标记S-24,进一步对该基因进行表达分析,发现该基因在突变体的叶、茎和穗中都表现出明显的下调,初步将LOC_Os11g17600作为DDF2候选基因。【结论】DDF2是一个同时控制水稻茎/叶和花器官发育的新基因。 展开更多
关键词 水稻 矮化 花器官 DWARF and deformed FLOWER 2(ddf2) 基因定位
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Microstructure evolution of alumina dispersion strengthened copper alloy deformed under different conditions 被引量:3
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作者 李灵 李周 +3 位作者 雷前 肖柱 刘斌 刘娜 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第12期3953-3958,共6页
Microstructure and texture evolution of Cu-0.23%Al2O3 dispersion strengthened copper alloy, deformed at room temperature or cryogenic temperature, were investigated. The main textures in hot-extruded specimen were Bra... Microstructure and texture evolution of Cu-0.23%Al2O3 dispersion strengthened copper alloy, deformed at room temperature or cryogenic temperature, were investigated. The main textures in hot-extruded specimen were Brass {011} 〈211〉 and Cube {100} 〈100〉. Textures of Brass {011} 〈211〉 and Goss {011} 〈100〉 were observed in specimen after deformation at room temperature; while textures of Brass {011} 〈211〉, Goss {011} 〈100〉 and S {123} 〈634〉 were detected after deformation at cryogenic temperature. It is believed that the additional Al2O3 nanoparticles can result in dislocation pinning effect, which can further lead to the suppression of dislocations cross-slip. While in the specimen deformed at cryogenic temperature, both pinning effect and cryogenic temperature are responsible for the formation of Brass, Goss and S textures. 展开更多
关键词 cryogenic deformation microstructure TEXTURE dispersion strengthened copper alloy
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Micro-structural evolution and their effects on physical properties in different types of tectonically deformed coals 被引量:45
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作者 Yiwen Ju Kray Luxbacher +4 位作者 Xiaoshi Li Guochang Wang Zhifeng Yan Mingming Wei Liye Yu 《International Journal of Coal Science & Technology》 EI CAS 2014年第3期364-375,共12页
The macromolecular structure of tectonically deformed coals(TDC)may be determined by the deformation mechanisms of coal.Alterations of the macromolecular structure change the pore structure of TDC and thereby impact p... The macromolecular structure of tectonically deformed coals(TDC)may be determined by the deformation mechanisms of coal.Alterations of the macromolecular structure change the pore structure of TDC and thereby impact physical properties such as porosity and permeability.This study focuses on structure and properties of TDC from the Huaibei and Huainan coal mining areas of southern North China.Relationships between the macromolecular structure and the pore structure of TDC were analyzed using techniques such as X-ray diffraction,high-resolution transmission electron microcopy,and the low-temperature nitrogen adsorption.The results indicated that the directional stress condition can cause the arrangement of basic structural units(BSU)more serious and closer.And,the orientation is stronger in ductile deformed coal than in brittle deformed coal.Tectonic deformation directly influences the macromolecular structure of coal and consequently results in dynamic metamorphism.Because the size of BSU in brittle deformed coal increases more slowly than in ductile deformed coal,frictional heating and stress-chemistry of shearing areas might play a more important role,locally altering coal structure under stress,in brittle deformed coal.Strain energy is more significant in increasing the ductile deformation of coal.Furthermore,mesopores account for larger percentage of the nano-scale pore volume in brittle deformed coals,while mesopores volume in ductile deformed coal diminishes rapidly along with an increase in the proportion of micropores and sub-micropores.This research also approved that the deformations of macromolecular structures change nano-scale pore structures,which are very important for gas adsorption and pervasion space for gas.Therefore,the exploration and development potential of coal bed methane is promising for reservoirs that are subjected to a certain degree of brittle deformation(such as schistose structure coal,mortar structure coal and cataclastic structure coal).It also holds promise for TDC resulting from wrinkle structure coal of low ductile deformation and later superimposed by brittle deformation.Other kinds of TDC suffering from strong brittle-ductile and ductile deformation,such as scale structure coal and mylonitic structure coal,are difficult problems to resolve. 展开更多
关键词 Tectonically deformed coals Formation mechanisms Macromolecular structure Pore structure Micro-structured evolution Coal bed methane
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Response of Macromolecular Structure to Deformation in Tectonically Deformed Coal 被引量:8
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作者 LI Xiaoshi JU Yiwen +1 位作者 HOU Quanlin FAN Junjia 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第1期82-90,共9页
The structural evolution of tectonically deformed coals (TDC) with different deformational mechanisms and different deformational intensities are investigated in depth through X-ray diffraction (XRD) analysis on 3... The structural evolution of tectonically deformed coals (TDC) with different deformational mechanisms and different deformational intensities are investigated in depth through X-ray diffraction (XRD) analysis on 31 samples of different metamorphic grades (R : 0.7%-3.1%) collected from the Huaibei coalfield. The results indicated that there are different evolution characteristics between the ductile and brittle deformational coals with increasing of metamorphism and deformation. On the one hand, with the increase of metamorphism, the atomic plane spacing (d002) is decreasing at step velocity, the stacking of the BSU layer (Lc) is increasing at first and then decreasing, but the extension of the BSU layer (La) and the ratio of La/Lc are decreasing initially and then increasing. On the other hand, for the brittle deformational coal, d002 is increasing initially and then decreasing, which causes an inversion of the variation of Lc and La under the lower-middle or higher-middle metamorphism grade when the deformational intensity was increasing. In contrast, in the ductile deformational coals, d002 decreased initially and then increased, and the value of L~ decreased with the increase of deformational intensity. But the value of La increased under the lower-middle metamorphism grade and increased at first and then decreased under the higher-middle metamorphism grade. We conclude that the degradation and polycondensation of TDC macromolecular structure can be obviously impacted during the ductile deformational process, because the increase and accumulation of unit dislocation perhaps transforms the stress into strain energy. Meanwhile, the brittle deformation can transform the stress into frictional heat energy, and promote the metamorphism and degradation as well. It can be concluded that deformation is more important than metamorphism to the differential evolution of the ductile and brittle deformational coals. 展开更多
关键词 tectonically deformed coal X-ray diffraction deformational mechanism deformationalintensity macromolecular structure
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A robust deformed convolutional neural network(CNN)for image denoising 被引量:12
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作者 Qi Zhang Jingyu Xiao +2 位作者 Chunwei Tian Jerry Chun‐Wei Lin Shichao Zhang 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第2期331-342,共12页
Due to strong learning ability,convolutional neural networks(CNNs)have been developed in image denoising.However,convolutional operations may change original distributions of noise in corrupted images,which may increa... Due to strong learning ability,convolutional neural networks(CNNs)have been developed in image denoising.However,convolutional operations may change original distributions of noise in corrupted images,which may increase training difficulty in image denoising.Using relations of surrounding pixels can effectively resolve this problem.Inspired by that,we propose a robust deformed denoising CNN(RDDCNN)in this paper.The proposed RDDCNN contains three blocks:a deformable block(DB),an enhanced block(EB)and a residual block(RB).The DB can extract more representative noise features via a deformable learnable kernel and stacked convolutional architecture,according to relations of surrounding pixels.The EB can facilitate contextual interaction through a dilated convolution and a novel combination of convolutional layers,batch normalisation(BN)and ReLU,which can enhance the learning ability of the proposed RDDCNN.To address long-term dependency problem,the RB is used to enhance the memory ability of shallow layer on deep layers and construct a clean image.Besides,we implement a blind denoising model.Experimental results demonstrate that our denoising model outperforms popular denoising methods in terms of qualitative and quantitative analysis.Codes can be obtained at https://github.com/hellloxiaotian/RDDCNN. 展开更多
关键词 blind denoising CNN deformed block enhanced block
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MECHANICAL STABILIZATION OF DEFORMED AUSTENITEDURING CONTINUOUS COOLING TRANSFORMATION IN AC-Mn-Cr-Ni-Mo PLASTIC DIE STEEL 被引量:7
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作者 D.S.Liu G.D.Wang +1 位作者 X.H.Liu G.Z.Cui 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1998年第2期93-99,共7页
The influence of prior austenite deformed at different temperature on the subsequent continuous cooling bainitic transformation has been investigated in an C-Ma-Cr-Ni-Mo plastic die steel. The results show that the pr... The influence of prior austenite deformed at different temperature on the subsequent continuous cooling bainitic transformation has been investigated in an C-Ma-Cr-Ni-Mo plastic die steel. The results show that the prior deformation in low temperature region of austenite retards significantly the bainitic transformation. For the same continuous cooling schedule, as austenite deformed at lower temperature, the quantity of the classical sheaf-like bainite becomes less. The present results show that severe deformation leads to mechanical stabilization of austenite and causes the difficulty of bainitic ferrite propagation into the austenite. 展开更多
关键词 plastic die steel deformed austenite continuous cooling bainitic transformation mechanical stabilization of austenite
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Study of seismic behavior of PHC piles with partial normal-strength deformed bars 被引量:3
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作者 Zhang Xizhi Zhang Shaohua +1 位作者 Xu Shengbo Niu Sixin 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2020年第2期307-320,共14页
Nine PHC piles with partial normal-strength deformed bars were prepared in present study,and cyclic loading tests were implemented to evaluate these piles’seismic performance.The influence of the axial compression ra... Nine PHC piles with partial normal-strength deformed bars were prepared in present study,and cyclic loading tests were implemented to evaluate these piles’seismic performance.The influence of the axial compression ratio and the amount of normal-strength deformed bars on failure modes,crack patterns,strength,stiffness,and ductility were examined.The test findings indicate that the change of axial compression ratio has a noticeable influence on the failure mode of PHC piles.A larger axial compression ratio results in a higher cracking bending resistance,ultimate bending resistance,and initial stiffness,but the propagation heights of flexural cracks decrease as the axial compression ratio increases.Furthermore,increasing the amount of normal-strength deformed bars causes a slight decrease in ductility.Finally,a calculation formula was proposed to predict the flexural capacity of PHC piles with partial normal-strength deformed bars. 展开更多
关键词 PHC pile PRESTRESSED TENDONS deformed bars seismic behavior cyclic loading test FLEXURAL capacity
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Even and Odd Q-coherent State Representations of the Q-deformed Heisenberg-Weyl Algebra 被引量:4
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作者 WANG Fabo KUANG Leman 《Chinese Physics Letters》 SCIE CAS CSCD 1992年第12期629-632,共4页
We construct explicitly even and odd q-coherent states.These q-coherent states are introduced in terms of the q-functions defined in the paper.It is shown that the even and odd q-coherent states form a kind of represe... We construct explicitly even and odd q-coherent states.These q-coherent states are introduced in terms of the q-functions defined in the paper.It is shown that the even and odd q-coherent states form a kind of representations of the q-deformed Heisenberg-Weyl algebra which is realized in the form of matrix q-differential operators in the even and odd q-coherent state space.We also analyse some different between the even and odd q-CSs and the usual even and odd CSs. 展开更多
关键词 space. coherent deformed
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Experimental Research on Pore Structure and Gas Adsorption Characteristic of Deformed Coal 被引量:3
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作者 Guo Deyong Guo Li Miao Xinhui 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2014年第4期55-64,共10页
The pore structure and gas adsorption property of deformed coal with different degrees of metamorphism were tested by low-temperature nitrogen adsorption and isothermal adsorption experiments. The fractal theory and t... The pore structure and gas adsorption property of deformed coal with different degrees of metamorphism were tested by low-temperature nitrogen adsorption and isothermal adsorption experiments. The fractal theory and the Langmuir adsorption theory were used to analyze the experimental data. The test results showed that the deformed coal had more heterogeneous pore structures and open pores, and its specific surface area(SSA) and fractal dimension(D) were higher. There is a polynomial relationship between D and specific surface area as well as gas adsorption capacity(VL). The gas adsorption capacity of deformed coal is influenced by pore structure, coal rank, deformation and stress together, among which the pore structure is the main influencing factor for the adsorption capacity of deformed coal. The test pressure could affect the accuracy of the adsorption constants a and b, so the highest experiment pressure should be greater than the actual pressure of coal seam in order to reduce the deviation of adsorption constants. 展开更多
关键词 deformed COAL PORE structure NITROGEN ADSORPTION ISOTHERMAL ADSORPTION
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Odd Systems in Deformed Relativistic Hartree Bogoliubov Theory in Continuum 被引量:3
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作者 LI Lu-Lu MENG Jie +2 位作者 P.Ring ZHAO En-Guang ZHOU Shan-Gui 《Chinese Physics Letters》 SCIE CAS CSCD 2012年第4期43-46,共4页
In order to describe the exotic nuclear structure in unstable odd-A or odd-odd nuclei,the deformed relativistic Hartree Bogoliubov theory in continuum is extended to incorporate the blocking effect due to the odd nucl... In order to describe the exotic nuclear structure in unstable odd-A or odd-odd nuclei,the deformed relativistic Hartree Bogoliubov theory in continuum is extended to incorporate the blocking effect due to the odd nucleon.For a microscopic and self-consistent description of pairing correlations,continuum,deformation,blocking effects,and the extended spatial density distribution in exotic nuclei,the deformed relativistic Hartree Bogoliubov equations are solved in a Woods Saxon basis in which the radial wave functions have a proper asymptotic behavior at large r.The formalism and numerical details are provided.The code is checked by comparing the results with those of spherical relativistic continuum Hartree Bogoliubov theory in the nucleus 19O.The prolate deformed nucleus 15 C is studied by examining the neutron levels and density distributions. 展开更多
关键词 HARTREE deformed RELATIVISTIC
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Influence of combination forms of intact sub-layer and tectonically deformed sub-layer of coal on the gas drainage performance of boreholes: a numerical study 被引量:3
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作者 Wei Zhao Kai Wang +3 位作者 Rong Zhang Huzi Dong Zhen Lou Fenghua An 《International Journal of Coal Science & Technology》 EI 2020年第3期571-580,共10页
High concentration and large flow flux of gas drainage from underground coal seams is the precondition of reducing emission and large-scale use of gas.However,the layered occurrence of coal seams with tectonically def... High concentration and large flow flux of gas drainage from underground coal seams is the precondition of reducing emission and large-scale use of gas.However,the layered occurrence of coal seams with tectonically deformed sub-layers and intact sub-layers makes it difficult to effectively drain gas through commonly designed boreholes.In this study,the gas drainage performance in coal seams with different combinations of tectonically deformed sub-layers and intact sub-layers was numerically analyzed.The analysis results show that the gas drainage curve changes from a single-stage line to a dual-stage curve as the permeability ratios of Zone II(kII)and Zone I(kI)increase,raising the difficulty in gas drainage.Furthermore,a dual-system pressure decay model based on the first-order kinetic model was developed to describe the dual-stage characteristics of pressure decay curves with different permeability ratios.In the end,the simulation results were verified with reference to in-situ drainage data from literature.The research results are helpful for mines,especially those with layered coal seams comprising tectonically deformed sub-layers and intact sub-layers,to choose appropriate gas drainage methods and develop the original drainage designs for achieving better gas drainage performance. 展开更多
关键词 Tectonically deformed coal Pressure decay Permeability Hydraulic flushing boreholes
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Tectonically deformed coal types and pore structures in Puhe and Shanchahe coal mines in western Guizhou 被引量:19
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作者 Li Ming Jiang Bo +3 位作者 Lin Shoufa Wang Jilin Ji Mingjun Qu Zhenghui 《Mining Science and Technology》 EI CAS 2011年第3期353-357,共5页
To evaluate the effect of tectonic deformation on coal reservoir properties, we provide an analysis of the types of tectonically deformed coal, macroand microscopic deformation and discuss pore structural characterist... To evaluate the effect of tectonic deformation on coal reservoir properties, we provide an analysis of the types of tectonically deformed coal, macroand microscopic deformation and discuss pore structural characteristics and connectivity based on samples from the Puhe and Shanchahe coal mines. Our research shows that the tectonically deformed coal mostly includes cataclastic structural coal, mortar structural coal and schistose structural coal of a brittle deformation series. The major pore structures of different types of tectonically deformed coal are transitional pores and micropores. The pore volumes of macropores and visible fracture pores produced by structural deformations vary over a large range and increase with the intensity of tectonic deformation. Mesopores as connecting passages develop well in schistose structural coal. According to the shapes of intrusive mercury curves, tectonically deformed coal can be divided into parallel, open and occluded types. The parallel type has poor connectivity and is relatively closed; the open type reflects uniformly developed open pores with good connectivity while the occluded type is good for coalbed methane enrichment, but has poor connectivity between pores. 展开更多
关键词 Puhe and Shanchahe coal minesTectonically deformed coalPore structure Coalbed methane
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Experimental research on bond strength of deformed GFRP rebars with different surface configurations 被引量:2
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作者 郝庆多 王言磊 欧进萍 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第4期469-474,共6页
Based on the Canadian Standards Association(CSA) criterion,experiments on 30 pull-out specimens were conducted to study the bond strength of deformed GFRP rebars with 8 different surface configurations.Each rebar was ... Based on the Canadian Standards Association(CSA) criterion,experiments on 30 pull-out specimens were conducted to study the bond strength of deformed GFRP rebars with 8 different surface configurations.Each rebar was embedded in a 150 mm concrete cube,and the test embedded length was four times of the rebar diameter.Relationship between the mode of failure,the average bond strength and the average bond strength-slip for each rebar was analyzed.Results show that the failure mode of all specimens is the shearing off or desquamation of ribs,no splitting cracks appear on the cube specimens.The bond stress of deformed GFRP rebars mainly depends on the mechanical interaction between the ribs of the bar and the surrounding concrete,and the bond strength of deformed GFRP rebars is improved obviously.The optimal rib spacing is less than 2.5 times of the rebar diameter,and the rib height is more than 3% of the rebar diameter. 展开更多
关键词 deformed GFRP rebars concrete bond strength pull-out test rib spacing rib height optimalsurface configuration
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Deformed coal types and pore characteristics in Hancheng coalmines in Eastern Weibei coalfields 被引量:9
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作者 xue Guangwu Liu Hongfu Li Wei 《International Journal of Mining Science and Technology》 SCIE EI 2012年第5期681-686,共6页
Based on SEM observance,the methods of low-temperature nitrogen and isothermal adsorption were used to test and analyze the coal samples of Hancheng,and pore structure characteristics of tectonic coals were discussed.... Based on SEM observance,the methods of low-temperature nitrogen and isothermal adsorption were used to test and analyze the coal samples of Hancheng,and pore structure characteristics of tectonic coals were discussed.The results indicate that in the same coal rank,stratification and crack are well developed in cataclastic coal,which is mostly filled by mineral substance in the geohydrologic element abundance,results in pore connectivity variation.Granulated and mylonitic coal being of these characteristics,as develop microstructures and exogenous fractures as well as large quantity of pores resulted from gas generation and strong impermeability,stimulate the recovery of seepage coal,improve coal connectivity and enhance reservoir permeability.Absorption pore(micro-pore) is dominant in coal pore for different coal body structure,the percentage of which pore aperture is from 1 to 100 nm is 71.44% to 88.15%,including large of micro-pore with the 74.56%-94.70%;with the deformation becoming more intense in the same coal rank,mesopore enlarge further,open-end pores become thin-neck-bottle-shaped pores step by step,specific surface area of micro-pore for cataclastic coal is 0.0027 m 2 /g,while mylonitic coal increases to 7.479 m 2 /g,micro-pore gradually play a dominant role in effecting pore structural parameters. 展开更多
关键词 deformed coal Pore structure Hg-injection Isotherm adsorption
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A co-rotational updated Lagrangian formulation for a 2D beam element with consideration of the deformed curvature 被引量:1
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作者 Nian-wen ZHANG Gen-shu TONG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第11期1480-1489,共10页
A tensor-based updated Lagrangian (UL) formulation for the geometrically nonlinear analysis of 2D beam-column structures is developed by using curvilinear coordinates, which has considered the effects of the deforme... A tensor-based updated Lagrangian (UL) formulation for the geometrically nonlinear analysis of 2D beam-column structures is developed by using curvilinear coordinates, which has considered the effects of the deformed curvature. Between the known configuration C1 and the desired configuration C2, a configuration C2^* derived by rigid-body motion of C1 is introduced to eliminate the element-end transverse displacements between C2^* and C2. A stiffness matrix is obtained in C2^*; and then by a transformation defined by the element-end displacements, the stiffness matrix in C2^* is transformed into that in CI. Comparing the stiffness matrix with that in the conventional UL formulation for a 2D beam element, the initial displacement stiffness matrix emerges, which results from the deformed curvature within the element. Numerical examples have verified the accuracy and efficiency of the present formulation, and the results show that the deformed curvatures have significant effects when deformations are large. 展开更多
关键词 deformed curvature Beam element Updated Lagrangian (UL) formulation Geometrical no-linearity Finite element
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Well-Deformed Oblate K Isomers Induced by Oblate Intruder States 被引量:1
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作者 XU Fu-Rong 《Chinese Physics Letters》 SCIE CAS CSCD 2001年第6期750-752,共3页
With configuration-constrained potential energy surfaces,it has been found that the neutron-deficient Z≈82 nuclei can have well-deformed oblate K isomers which are formed by exciting quasiparticles to the proton i_(1... With configuration-constrained potential energy surfaces,it has been found that the neutron-deficient Z≈82 nuclei can have well-deformed oblate K isomers which are formed by exciting quasiparticles to the proton i_(13/2) and h_(9/2) oblate intruder orbitals.To achieve the configuration constrained calculations,the maximum-overlap method of wavefunctions is proposed.In the present calculations of quasiparticle states,quadrupole pairings are included.The observed K^(π)=11^(-) isomer in 188Pb is confirmed to be oblately deformed,with energy consistent with the experiment.Some low-lying oblate isomeric states are predicted for ^(187)Tl. 展开更多
关键词 deformed CONSTRAINED QUASI
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