Theoretical study on spherical proton emission

The proton radioactivity half-lives of spherical proton emitters are investigated within a generalized liquid drop model (GLDM), including the proximity effects between nuclei in a neck and the mass and charge asymmetry. The penetrability is calculated in the WKB approximation and the assault frequency is estimated by the quantum mechanism method considering the structure of the parent nucleus. The spectroscopic factor is taken into account in half-life calculation, which is obtained by employing the relativistic mean field (RMF) theory. The half-lives within the GLDM are compared with the experimental data and other theoretical values. The results show that the GLDM works quite well for spherical proton emitters when the assault frequency is estimated by the quantum mechanical method and the spectroscopic factor is considered.

Dynamical analysis on heavy-ion fusion reactions near Coulomb barrier

The shell correction is proposed in the improved isospin dependent quantum molecular dynamics (Im-IQMD) model, which plays an important role in heavy-ion fusion reactions near Coulomb barrier. By using the ImIQMD model, the static and dynamical fusion barriers, dynamical barrier distribution in the fusion reactions are analyzed systematically. The fusion and capture excitation functions for a series of reaction systems are calculated and compared with experimental data. It is found that the fusion cross sections for neutron-rich systems increase obviously, and the strong shell effects of two colliding nuclei result in a decrease of the fusion cross sections at the sub-barrier energies. The lowering of the dynamical fusion barriers favors the enhancement of the sub-barrier fusion cross sections, which is related to the nucleon transfer and the neck formation in the fusion reactions.

Systematic study on alpha decay half-lives of superheavy nuclei

The a-decay half-lives of a set of superheavy nuclear isotope chain from Z = 105 to 120 have been analyzed systematically within the WKB method, and some nuclear structure features are found. The decay barriers have been determined in the quasi-molecular shape path within the Generalized Liquid Drop Model (GLDM) including the proximity effects between nucleons in a neck and the mass and charge asymmetry. The results are in reasonable agreement with the published experimental data for the alpha decay half-lives of isotopes of charge 112, 114, and 116, of the element 294118 and of some decay products. A comparison of present calculations with the results by the DDM3Y effective interaction and by the Viola-Seaborg Sobiczewski (VSS) formulae is also made. The experimental a decay half lives all stand in between the GLDM calculations and VSS formula results. This demonstrates the possibility of these models to provide reasonable estimates for the half-lives of nuclear decays by a emissions for the domain of SHN. The half-lives of these new nuclei are thus well tested from the reasonable consistence of the macroscopic, the microscopic, the empirical formulae and the experimental data. This also shows that the present data of SHN themselves are consistent. It could suggest that the present experimental claims on the existence of new elements Z = 110 similar to 118 are reliable. It is expected that greater deviations of a few SHN between the data and the model may be eliminated by further improvements on the precision of the measurements.

alpha decay half-lives of new superheavy nuclei within a generalized liquid drop model

The alpha decay half-lives of the recently produced isotopes of the 112, 114, 116 and 118 nuclei and decay products have been calculated in the quasi-molecular shape path using the experimental Q(alpha) value and a Generalized Liquid Drop Model including the proximity effects between nucleons in the neck or the gap between the nascent fragments. Reasonable estimates are obtained for the observed alpha decay half-lives. The results are compared with calculations using the Density-Dependent M3Y effective interaction and the Viola-Seaborg-Sobiczewski formulae. Generalized Liquid Drop Model predictions are provided for the alpha decay half-lives of other superheavy nuclei using the Finite Range Droplet Model Q(alpha) and compared with the values derived from the VSS formulae.

Alpha decay half-lives of new superheavy elements through quasimolecular shapes

The lifetimes of alpha decays of the recently produced isotopes of the elements 112, 114, 116 and the element (294)118 and of some decay products have been calculated theoretically within the Wentzel-Kramers-Brillouin approximation. The alpha decay barriers have been determined in the quasimolecular shape path within a generalized liquid drop model including the proximity effects between nuclei in a neck, the mass and charge asymmetry and the precise nuclear radius. These calculations provide reasonable estimated for the observed alpha decay lifetimes. The calculated results have been compared with the results of the density-dependent M3Y effective interaction and the experimental data. It is indicated that the theoretical foundation of the generalized liquid drop model is as good as that of the microscopic DDM3Y model, at least in the sense of predicting the T-1/2 values as long as one uses a correct alpha decay energy. The half lives of these new nuclei are well tested from the consistence of the macroscopic, the microscopic and the experimental data.

Study on dynamic fusion barrier in heavy-ion fusion reactions

By means of the improved quantum molecular dynamics model, the incident energy dependent dynamical fusion potential barriers for heavy nucleus reaction systems are investigated. It is found that with decrease of incident energy the lowest dynamic barrier is obtained which approaches to the adiabatic static barrier and with increase of the incident energy the dynamic barrier goes up to the diabatic static barrier. Based on the dynamical study a microscopic understanding of the extra-push in fusion reactions of heavy systems and a new explanation of tunneling process for the fusion at the incident energy below the static and above the lowest dynamic barrier are presented. In order to understand the energy dependence of the dynamical barrier we also pay a great attention to study the neck formation and shape deformation during the dynamic lowering of the barrier.

中能重离子碰撞中的同位旋效应及非对称核物质的状态方程研究

本论文介绍了放射性核束物理研究的现状以及当前常用的几种同位旋相关的重离子微观输运理论，系统描述了非对称核物质的状态方程、中能重离子碰撞中的同位旋效应以及中子星的性质。基于 Hartree-Fock 理论和扩展的 Skyrme 相互作用，在核物质近似下得到了一个非相对论性的密度、温度和同位旋相关的核物质状态方程 (IEOS)。系统研究了核物质状态方程的同位旋效应。讨论了核子的平均场、核物质的不可压缩系数、核子的有效质量以及核物质临界温度的同位旋相关性，并且给出了核物质饱笔点处的饱和密度、不可压缩系数以及单核子结合能的抛物线规律。同时，探讨了对称能的温度和密度相关性，给出了零温度时对称能的解析表达式，并提出了对称能温度相关性的抛物线规律，发现对称能随着温度的升高而减小。另外，基于以上的同位旋相关的核物质状态方程，对 ALADIN's Caloric Curve 给出了一种静态解释。在传统量子分子动力学 (QMD) 模型的基础上，通过在相互作用平均场、两体碰撞、泡利阻塞、初始化以及碎片构造过程中适当地考虑同位旋自由度，得到了一个同位旋相关的 QMD 模型 (IQMD 模型)。利用IQMD模型系统研究了中能重离子碰撞中的同位旋效应。例如，中能重离子碰撞中同位旋自由度的弛豫、重离子碰撞中核子前平衡发射的同位旋效应、重离子碰撞中的集体流（包括直接流、转动流、挤出流和径向流）及其同位旋相关性、原子核多重碎裂的同位旋效应及其消失、重离子碰撞中的化学不稳定性以及中能重离子碰撞中如何选取事件的碰撞参数及其同位旋效应等。同样，在传统的 Boltzmann-Langevin 方程中适当地考虑同位旋自由度，得到了同位旋相关的Boltzmann-Langevin方程 (IBLE)，利用IBLE研究了 ~(19)Na的产生截面。另外，利用IQMD模型探讨了多重碎裂的"neck" 机制以及重离子碰撞中局域势的有限程效应。基于前面给出的非相对论的核物质状态方程，系统研究了中子星的性质，如中子星的化学组份、质量、结合能、半径、密度剖面、转动惯量及表面红移等。结果表明，使用一些常用的 Skyrme 势参数能够给出与天文学观测相一致的结果。

束鹿凹陷泥灰岩储层综合评价与加砂压裂技术研究与应用

Luo Ning ( Mineralogy, Petrology, Deposit Mineralogy) Directed by Fu Liyun With the increase of the level of exploration and development, North China field, as one of the maturing fields in the east, has gradually turned their prospecting targets to frontiers such as deep zones, lithologic hydrocarbon reservoirs, low permeable layers, special lithostromes, etc, which propose new challenges to mating technique of exploration engineering. In it, the special lithostrome of clay carbonate in Shu-Lu cave in Middle Flank exploration area locates in Es_3 generating rock. The area distribution is large, formation thickness is over 100 meters, the oil accumulation condition is excellent, prognostic reserves is over 80,000,000 tons, but how to effectively stimulate the special low permeable and fractured reservoir has become the bottle neck problem of stimulation and stable yields. In this thesis, through comprehensive evaluation and analysis of lithology, lithomechanics, hydrocarbon reservoir characteristics, the characteristics of fluid flow through porous medium and the stimulation measures in the past, we acquire new cognition of clay carbonate reservoirs, in addition, the research and application of first hydraulic fracturing has gained positive effect and formed commensurable comprehensive reservoir evaluation technique and mating engineering technique of hydraulic fracturing. The main cognitions and achievements are as follows: 1.Study of geological information such as lithololy analysis and nuclear magnetic logging, etc, indicates that clay carbonate formation of Shu-Lu cave is anisotropic, low permeable with high shale content, whose accumulation space gives priority to microcracks. 2.The analysis of lithomechanics of clay carbonate indicates that the hardness is moderate, Young’s modulus is between that of sandstone and limestone, clay carbonate presents plastic property and its breakdown pressure is high because of the deep buried depth. 3.The analysis of the drillstem test curves indicates that the flow and build-up pressure curve of clay carbonate of Shu-Lu cave mainly has three types: formation contamination block-up type, low permeable type, formation energy accumulation slowness type; the reservoir characteristics presents double porosity media, radial compounding, uniform flow vertical fracture, isotropy, moniliform reservoir type. The target well Jingu 3 belongs to moniliform reservoir type. 4.Through recognition and re-evaluation of the treatment effect and technologic limitations of acidizing, acid fracturing and gelled acidizing in the past, based on the sufficient survey and study of hydraulic fracturing home and abroad, combined with comprehensive formation study of target well, we launched the study of the optimization of hydraulic fracturing technique, forming the principal clue and commensurable mating technology aimed at clay carbonate formation, whose targets are preventing leak off, preventing sand bridge, preventing embedment, controlling fracture height, forming long fracture. 5. Recognition of stimulation effect evaluation.

开发早期油藏动态地质模型与油藏工程优化研究——以埕岛油田馆上段油藏为例

In order to developing reservoir of Upper of Ng at high-speed and high-efficient in Chengdao oilfield which is located in the bally shallow sea, the paper builds up a series of theory and means predicting and descripting reservoir in earlier period of oilfield development. There are some conclusions as follows. 1. It is the first time to form a series of technique of fine geological modeling of the channel-sandy reservoir by means of mainly seismic methods. These technique include the logging restriction seismic inversion, the whole three dimension seismic interpretation, seismic properties analysis and so on which are used to the 3-dimension distributing prediction of sandy body, structure and properties of the channel reservoir by a lot of the seismic information and a small quantity of the drilling and the logging information in the earlier stage of the oil-field development. It is the first time that these methods applied to production and the high-speed development of the shallow sea oilfield. The prediction sandy body was modified by the data of new drilling, the new reservoir prediction thinking of traced inversion is built. The applied effect of the technique was very well, according to approximately 200 wells belonging to 30 well groups in Chengdao oilfield, the drilling succeeded rate of the predicting sandy body reached 100%, the error total thickness only was 8%. 2. The author advanced the thinking and methods of the forecasting residual-oil prediction at the earlier stage of production. Based on well data and seismic data, correlation of sediment units was correlated by cycle-correlation and classification control methods, and the normalization and finely interpretation of the well logging and sedimentation micro-facies were acquired. On the region of poor well, using the logging restriction inversion technique and regarding finished drilling production well as the new restriction condition, the sand body distributing and its property were predicted again and derived 3-dimension pool geologic model including structure, reservoir, fluid, reservoir engineering parameter and producing dynamic etc. According to the reservoir geologic model, the reservoir engineering design was optimized, the tracking simulation of the reservoir numerical simulation was done by means of the dynamic data (pressure, yield and water content) of development well, the production rule and oil-water distributing rule was traced, the distributing of the remaining oil was predicted and controlled. The dynamic reservoir modeling method in metaphase of development was taken out. Based on the new drilling data, the static reservoir geologic model was momentarily modified, the research of the flow units was brought up including identifying flow units, evaluating flow units capability and establishing the fine flow units model; according to the dynamic data of production and well testing data, the dynamic tracing reservoir description was realized through the constant modification of the reservoir geologic model restricted these dynamic data by the theory of well testing and the reservoir numerical simulation. It was built the dynamic tracing reservoir model, which was used to track survey of the remaining oil on earlier period. The reservoir engineering tracking analysis technique on shallow sea oilfield was founded. After renewing the structure history since tertiary in Chengdao area by the balance section technique and estimating the activity character of the Chengbei fault by the sealing fault analysis technique, the meandering stream sediment pattern of the Upper of Ng was founded in which the meandering border was the uppermost reservoir unit. Based on the specialty of the lower rock component maturity and the structure maturity, the author founded 3 kinds of pore structure pattern in the Guanshang member of Chengdao oil-field in which the storing space mainly was primary (genetic) inter-granular pore, little was secondary solution pore and the inter-crystal pore tiny pore, and the type of throat mainly distributed as the slice shape and the contract neck shape. The positive rhythmic was briefly type included the simple positive rhythm, the complex positive rhythm and the compound rhythm. Interbed mainly is mudstone widely, the physical properties and the calcite interbed distribute localized. 5. The author synthetically analyzed the influence action of the micro-heterogeneity, the macro-heterogeneity and the structure heterogeneity to the oilfield water flood development. The efficiency of water flood is well in tiny structure of convex type or even type at top and bottom in which the water breakthrough of oil well is soon at the high part of structure when inject at the low part of structure, and the efficiency of water flood is poor in tiny structure of concave type at top and bottom. The remaining oil was controlled by sedimentary facies; the water flooding efficiency is well in the border or channel bar and is bad in the floodplain or the levee. The separation and inter layer have a little influence to the non-obvious positive rhythm reservoir, in which the remaining oil commonly locate within the 1-3 meter of the lower part of the separation and inter layer with lower water flooding efficiency.