Abstract: The present invention relates to the technical field of disaster model experiment of underground engineering, and more particularly to an experimental system for surrounding rock crack evolution and water inrush disaster change in a tunnel excavation of a near-covered karst cave. The experimental system includes a base, an upper crossbeam, standing columns, an experimental cabin, guide rails, a tunnel excavation device and an experimental control system. By setting a tunnel excavation device instead of the traditional manual excavation experimental system, the step-by-step excavation of the tunnel is realized. A camera inside the tunnel mold collects real-time images of the whole process of tunnel excavation. The front side plate is separated from the whole experimental cabin, such that the deformation and damage of the front side of the physical model can be directly observed.

Abstract: The present invention relates to the technical field of disaster model experiment of underground engineering, and more particularly to an experimental system for surrounding rock crack evolution and water inrush disaster change in a tunnel excavation of a near-covered karst cave. The experimental system includes a base, an upper crossbeam, standing columns, an experimental cabin, guide rails, a tunnel excavation device and an experimental control system. By setting a tunnel excavation device instead of the traditional manual excavation experimental system, the step-by-step excavation of the tunnel is realized. A camera inside the tunnel mold collects real-time images of the whole process of tunnel excavation. The front side plate is separated from the whole experimental cabin, such that the deformation and damage of the front side of the physical model can be directly observed.

Abstract: A DSC (Differential Scanning calorimetry) electrode system capable of applying an electric field includes a differential scanning calorimeter, a computer, a signal generator, a self-pressurization liquid nitrogen tank and a reference crucible, wherein the self-pressurization liquid nitrogen tank is connected to the differential scanning calorimeter and used for controlling temperature in real time; the differential scanning calorimeter is connected to the computer and used for transmitting signals and recording experiment results. The DSC electrode system also includes a microelectrode crucible that includes a ceramic crucible, a ceramic crucible cover, welding spots, two electrodes and electrode wires, wherein the two electrodes are respectively fixed in the ceramic crucible; a gap is reserved between the electrodes and used for storing a tested sample; the welding spots are reserved at upper ends of the electrodes.

Abstract: A Differential Scanning calorimetry (DSC) thermal analysis method for the action of an applied electric field includes: step 1, in an experiment module of a differential scanning calorimeter, placing a microelectrode crucible and a reference crucible on corresponding sensors, connecting electrode wires of the microelectrode crucible with a signal generator, setting signal parameters to be output, placing a tested sample in a gap between electrodes, closing a microelectrode crucible lid, and closing the experiment module; step 2, at a temperature-varying stage, measuring a DSC curve of the tested sample under the action of an electric field, and at a reheating stage, measuring a DSC curve of the tested sample with no electric field; and step 3, analyzing the DSC curves in combination with the related theories of dielectrics and thermodynamics, and calculating an electric field intensity of the tested sample and a phase transformation rate of the tested sample.

Abstract: A Differential Scanning calorimetry (DSC) thermal analysis method for the action of an applied electric field includes: step 1, in an experiment module of a differential scanning calorimeter, placing a microelectrode crucible and a reference crucible on corresponding sensors, connecting electrode wires of the microelectrode crucible with a signal generator, setting signal parameters to be output, placing a tested sample in a gap between electrodes, closing a microelectrode crucible lid, and closing the experiment module; step 2, at a temperature-varying stage, measuring a DSC curve of the tested sample under the action of an electric field, and at a reheating stage, measuring a DSC curve of the tested sample with no electric field; and step 3, analyzing the DSC curves in combination with the related theories of dielectrics and thermodynamics, and calculating an electric field intensity of the tested sample and a phase transformation rate of the tested sample.

Abstract: A DSC (Differential Scanning calorimetry) electrode system capable of applying an electric field includes a differential scanning calorimeter, a computer, a signal generator, a self-pressurization liquid nitrogen tank and a reference crucible, wherein the self-pressurization liquid nitrogen tank is connected to the differential scanning calorimeter and used for controlling temperature in real time; the differential scanning calorimeter is connected to the computer and used for transmitting signals and recording experiment results. The DSC electrode system also includes a microelectrode crucible that includes a ceramic crucible, a ceramic crucible cover, welding spots, two electrodes and electrode wires, wherein the two electrodes are respectively fixed in the ceramic crucible; a gap is reserved between the electrodes and used for storing a tested sample; the welding spots are reserved at upper ends of the electrodes.

Abstract: An isolated DNA molecule which includes a promoter-effective region of a Tetrahymena metallothionein gene, as well as a chimeric gene, expression vectors, and host cells containing the same. Also disclosed is a method of expressing an RNA or a polypeptide of interest using a chimeric gene of the invention.