| The work described in this thesis is devoted to the study and the development of the specific interface configurations of solid neutron capture-detection junction and their production scheme,and the dynamic properties of the surface films at the certain interfaces.The specific contents are as follows:The first part is about the research work on interface configuration,which includes the following aspects:In view of the research on solid neutron detection materials and devices which is being developed all over the world,a number of specific interfacial configurations and their production schemes of novel and efficient neutron capture-detection junctions suitable for their application requirements have been developed.The relationship between the interfacial configuration parameters of neutron capture-detection junction and the neutron detection efficiency have been simulated.This part of the study is described in the first and second chapters of this thesis.In chapter 1,the background knowledge of neutron detection is summarized,such as neutron and its basic characteristics,neutron generation and classification,neutron source and its species,interaction between neutron and nucleus,and application of neutron technology.In chapter 2,the following are the details:The basic principles and methods of neutron detection,the main technical specifications and classification,and the development trend of neutron detectors,and the development status of solid neutron detectors are introduced.The working mechanism of indirect semiconductor neutron detector and direct semiconductor neutron detector,and the design idea of novel solid neutron detector are also described in detail.The work accomplished is as follows:1)optimization design of the interface geometric morphology and structure and geometric parameters of indirect solid neutron capture-detection junction.2)the production scheme for B-Si interface configuration with three-dimensional microstructure of indirect solid neutron capture-detection junctions,which is made of cylindrical columnar silicon substrate by etching method or made of porous silicon directly.3)the production scheme for Interface configuration with B5C and n-Si laminated multilayer films,and three-dimensional Si-BC microstructure,respectively.4)the scheme of composite correlation measurement of multiple solid neutron capture-detection P-N junctions.The results of the simulation experiment of the relationships between the interfacial configuration parameters of neutron capture-detection junction and the neutron detection efficiency are given,which include the following:between neutron count and diameter of hole and separation between holes in the case of point source incidence and non-point source incidence respectively;between neutron count and diameter of hole in the case of different separation between holes;between neutron count and depth of hole;between neutron count and diameter of hole made of materials of different 10B purity respectively;between neutron count and neutron energy;between neutron count and incidence Angle.In this way,some key problems about basic physics,materials and electronic technology are explored and solved,such as the contradiction between the long free path of captured neutrons and the short free range of charged particles produced from the captured neutrons.It lays a foundation for the development of novel,efficient and portable solid neutron detection materials and devices with high performance to price ratio,to solve the problem that neutron detection is still basically stagnant on the basis of gas detector technology and has some limitations on its development and application.Neutron detection and related technologies in basic scientific research including on neutron itself,energy and medical treatment,industrial and agricultural and economic production,highly advanced technology,counter-terrorism,military and defense,and other fields are playing a more and more important role.The second part is about the study on the properties of the surface film based on QCM and SPR techniques,such as quality specific response of SPR and QCM to the mass of adsorbates at interfaces,molecular conformation and its variation of films adsorbed at the interface,glass transition in films deposited at the interface.This part of the study is described in chapters 3 to 5 of this thesis.In chapter 3,specific responses of SPR and QCM to the mass of adsorbates at solid-liquid interfaces are described in detail.The results show that:the proportional relation between SPR signal and adsorbed mass at solid-liquid interfaces comes from a linear relation between surface refractive index and surface concentration,under a small variation of surface refractive index,while the proportional relation between QCM signal and adsorbed mass lies in a linear relation between surface viscosity and surface concentration,and a small variation of surface viscosity.The ratio of SPR and QCM signals to the surface mass is dominated by the refractive index increment and intrinsic viscosity,respectively.In chapter 4,the theoretical derivation of the modified Sauerbrey equation of QCM is described in detail.A simple proportional relation between ?f which is the output signal of QCM for characterization of Solid-Liquid Interface proterties on crystal surface and surface mass at solid-liquid interfaces has been derived.The physical meaning of the proportional coefficient has been analyzed.According to the modified Sauerbrey equation,?f/?m relies on the intrinsic viscosity of adsorbates.which can semi-quantitatively describe the conformation of isolated adsorbates at solid-liquid interfaces.In chapter 5,the study on Glass Transitions in PVB Films adsorbed on Quartz Crystal surface is described in detail.The results show that:rapid drops in the storage moduli of the PVB films at temperature close to that of glass transition of bulk PVB.No significant change in glass transition temperature Tg was found in high harmonics of the resonant frequency.As the film thickness decreases to below half micrometer;the glass transition temperature Tg also decreases with decreasing of the film thickness.Therefore,the dynamic properties of the surface film adsorbed or deposited at the interface are explored,and the micro structure and conformation changes of the surface film are further understood,which is helpful to the popularization and improvement of the surface film in practical application. |
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