COMPATIBILITY AND CRYSTALLIZATION OF TETRAHYDROFURAN-METHYL METHACRYLATE DIBLOCK COPOLYMER/POLYTETRAHYDROFURAN BLENDS

The compatibility and crystallization of tetrahydrofuran-methyl methacrylate diblock copolymer (PTHF-b-PMMA)/tetrahydrofuran homopolymer (PTHF) blends were studied. Our results showed that the crystallization and morphology of compatible PTHF-b-PMMA/PTHF

THE COMPATIBILITY AND CRYSTALLIZATION OF THE MIXTURES OF POLY (TETRAHYDROFURAN-b-METHYL METHACRYLATE) DIBLOCK COPOLYMER WITH POLYVINYL CHLORIDE HOMOPOLYMER

The compatibility and crystallization behaviour of the mixtures of poly (tetrahydrofuran-methyl methacrylate) diblock copolymer (PTHF-b-PMMA) with polyvinyl chloride has been studied. We found that the compatibility of these blends, in which there is special interaction between the homopolymer and the PMMA block of the copolymer, is much better than that of the AB/A type blends; and that the crystallization rate and crystallinity of PTHF microdomain changed greatly due to the swollen by PVC homopolymer. In this paper, these changes in cryatallization are well explained according to the theories of block copolymer blends and the density gradient model presented by JIANG Ming.

高可靠性红外车辆分离器设计与应用

本文给出了一种针对公路自动收费系统的车辆分离检测而设计的,利用红外线发射和接收所形成的光幕,完全消除跟车现象,并能将半挂车、全挂车、单车可靠分离的红外车辆分离器。高可靠性红外车辆分离器的设计很好克服了传统红外车辆分离器环境适应性差、故障率高等缺点。本文还介绍了光幕形成的基本原理,并阐述了硬件关键点及实现方法,给出了系统硬件原理图、软件基本设计思想。

DAS24-3B数据采集系统控制系统软件的研制与开发

Under the auspices of the 'knowledge-Innovation Program' of CAS, Institute of Geology and Geophysics has established the Broadband Seismic Laboratory. A new kind of 24-bit high-resolution seismograph DAS24-3B has been designed and manufactured in an effort of developing China's own technology of seismic array. Since these instruments will primarily be used in field operation, there is a need to optimize the system software of data acquisition system (DAS) to enhance its stability, compatibility and maintenance. The design ideas of the system software of DAS24-3B are partly learned from the advanced DAS 72A-08. In this system there are two exclusive communication programs DNAPI-COM1 and DNAPI-LPT1, which are suitable for all standard industrial computers with ECP parallel port and serial port. By these exclusive parallel and serial communication interface the system software is split into three parts, acquisition program, user's control program and graphical display program, which can function well in separate units and can run correctly in whole. The three parts of DAS24-3B's system software possess different functions and advantages. The function of acquisition program is to control the process of seismic data acquisition. DAS24-3B system reduced its power and harddisk read-write disturbance by using the extended memory attached to its CPU, which functions as enlarging the data buffer of system and lessening the times of harddisk read-write operations. Since GPS receiver of DAS is strongly sensitive to the around environment and has the possibility of signal loss the acquisition program has been designed with the ability to automatically trail the GPS locked time. The function of user's controlling program is to configure the system's work environment, to inform the user's commands to DAS, to trail the status of DAS in real-time. The function of graphical display program is to illustrate data in figures, to convert data file into some common formatted file, to split data file in parts and combine data files into one. Both user's control program and graphical display program are API (Application Programming Interface) in window 95/98 system. Both possess the features of clearness and friendship by use of all kind of window controls, which are composed by menu, toolbar, statusbar, dialogue box, message box, edit box, scrollbar, time control, button and so on. Two programs of systemic exception handles are provided to treat the trouble in field. The DAS24-3B DAS has been designed to be easier to use-better ability, more stable and simpler. It has been tested in field and base station and has been proved more suitable for field operation of seismic array than other native instruments.

宽频带地震数据采集系统的研制

The seismic data acquisition system is the most important equipment for seismic prospecting. The geophysicists have been paying high attention to the specification of the equipment used in seismic prospecting. Its specification and performance are of great concerned to acquire precisely and accurately seismic data, which show us stratum frame. But, by this time, limited by the technology, most of the Broad-band Seismic Recorder (BSR) for lithosphere research of our country were bought from fremdness which were very costliness and maintained discommodiously. So it is very important to study the seismic data acquisition system.The subject of the thesis is the research of the BSR, several items were included, such as: seismic data digitizer and its condition monitor design.In the first chapter, the author explained the significance of the implement of BSR, expatiated the requirement to the device and introduced the actuality of the BSR in our country.In the second chapter, the collectivity architecture of the BSR system was illustrated. Whereafter, the collectivity target and guideline of the performance of the system design were introduced. The difficulty of the system design and some key technology were analyzed, such as the Electro Magnetic Compatibility (EMC), system reliability technology and so on.In the third chapter, some design details of BSR were introduced. In the recorder, the former analog to digital converter (ADC) was separated from the later data transition module. According to the characteristic of seismic data acquisition system, a set high-resolution 24-bit ADC chip was chosen to the recorder design scheme. As the following part, the noise performance of the seismic data channel was analyzed.In the fourth chapter, the embedded software design of each board and the software design of the workstation were introduced. At the same time the communication protocol of the each module was recommendedAt the last part of this thesis, the advantages and the practicability of the BSR system design were summarized, and the next development items were suggested.