Abstract: Disclosed are a method and system for evaluating sonar self-noise at a ship design stage. The method includes: building a ship structure full-scale geometric simulation model; acquiring loss factors and sonar transducer space outfitting acoustic absorption coefficient material parameters; acquiring mechanical excitation, hydrodynamic excitation, and propeller excitation; inputting the loss factors and the sonar transducer space outfitting acoustic absorption coefficient material parameters into an established statistical energy evaluation model, and applying a mechanical excitation to a face plate of foundation of the built ship structure full-scale geometric simulation model, applying a hydrodynamic excitation to the surface of a ship hull, and applying a propeller excitation to a stern shaft to perform calculation of sonar self-noise of a ship to obtain total spectral density level of the sonar self-noise; and evaluating spectral density level calculation results by index requirements.

Abstract: Disclosed are a method and system for evaluating sonar self-noise at a ship design stage. The method includes: building a ship structure full-scale geometric simulation model; acquiring loss factors and sonar transducer space outfitting acoustic absorption coefficient material parameters; acquiring mechanical excitation, hydrodynamic excitation, and propeller excitation; inputting the loss factors and the sonar transducer space outfitting acoustic absorption coefficient material parameters into an established statistical energy evaluation model, and applying a mechanical excitation to a face plate of foundation of the built ship structure full-scale geometric simulation model, applying a hydrodynamic excitation to the surface of a ship hull, and applying a propeller excitation to a stern shaft to perform calculation of sonar self-noise of a ship to obtain total spectral density level of the sonar self-noise; and evaluating spectral density level calculation results by index requirements.

Abstract: A strain of ciliated protozoan is provided, which has an obvious promoting effect on germination and growth of plant seeds. The ciliated protozoan is Colpoda sp. JH2-5-4, with preservation number of CCTCC NO.C202229. After collecting over 2,000 Colpoda strains from soils across China, the present invention has screened and selected a highly efficient and active strain suitable for use as a microbial fertilizer in plant cultivation. The selected ciliated protozoan can significantly shorten the germination time of plant seeds and improve seedling survival rate.

Abstract: The present disclosure provides an efficient vibration reduction and isolation base supported by a chained panel fluid bladder, including a chained panel, the vibration reduction fluid bladder, vertical limiting devices and a bottom plate. The chained panel is a discontinuous structure formed by connecting chained substructure panels in series by panel hinge devices. The vibration reduction fluid bladder and the vertical limiting devices are fixedly installed between the chained panel and the bottom plate. The chained panel is constructed based on the impedance mismatch principle and provided with a mechanical device. Mechanical vibration energy is dissipated twice by the chained panel and the vibration reduction fluid bladder, thereby greatly reducing influences of mechanical device operation on a hull structure.

Abstract: An erection device and method for the marine hot launch of a rocket are provided. The erection device includes a launch vessel, a launch pad, an erection assembly, a guide member, a driving cylinder, a sliding member, and a connecting member. The sliding member cooperates with the guide member and is driven by the driving cylinder to move linearly. The connecting member has one end hinged to the erection assembly at a certain angle and the other end connected to the sliding member and is configured to move with the sliding member to drive the erection assembly to be erected on the launch pad. The erection device and method can achieve an effective erection of the rocket for marine hot launch with a desired erection effect and high stability.

Abstract: An erection device and method for the marine hot launch of a rocket are provided. The erection device includes a launch vessel, a launch pad, an erection assembly, a guide member, a driving cylinder, a sliding member, and a connecting member. The sliding member cooperates with the guide member and is driven by the driving cylinder to move linearly. The connecting member has one end hinged to the erection assembly at a certain angle and the other end connected to the sliding member and is configured to move with the sliding member to drive the erection assembly to be erected on the launch pad. The erection device and method can achieve an effective erection of the rocket for marine hot launch with a desired erection effect and high stability.

Abstract: Provided are a RNAi target gene that is lethal to aphids and the use thereof. Specifically, provided are six gene fragments resulting in the death of aphid nymphs and/or death thereof in the adult stage based on RNA interference technology. The death of the aphids can be caused by spraying a dsRNA-containing composition onto plants to feed aphids or directly spraying same onto the skin of the aphids.

Abstract: The present invention relates to pesticide preparations and methods based on RNAi technology. The invention discloses target genes (fragments) useful in the control of Lepidoptera insects. Nucleic acid inhibitors or hosts expressing the nucleic acid inhibitors, based on the nucleic acid sequences of these target genes, can effectively kill Lepidoptera insects. The invention also discloses applications using the nucleic acid inhibitors or hosts expressing the nucleic acid inhibitors.

Abstract: The present invention relates to pesticide preparations and methods based on RNAi technology. The invention discloses target genes (fragments) useful in the control of Lepidoptera insects. Nucleic acid inhibitors or hosts expressing the nucleic acid inhibitors, based on the nucleic acid sequences of these target genes, can effectively kill Lepidoptera insects. The invention also discloses applications using the nucleic acid inhibitors or hosts expressing the nucleic acid inhibitors.