To solve the problem of sealing between the barrel and the rubber ring of shell body during an launching process of aerodynamic extinguishing cannon, a rubber sealing model with bionic dimpled characteristics was esta...To solve the problem of sealing between the barrel and the rubber ring of shell body during an launching process of aerodynamic extinguishing cannon, a rubber sealing model with bionic dimpled characteristics was established based on the theory of bionic dimpled drag reduction and the principle of rubber sealing. In condition that the bionic dimpled characteristic diameters were 1, 2, 3, 4, and 5 mm, respectively, by numerical simulation, the influence of the installing compression of the rubber sealing ring on its surface stress and deformation was analyzed, and sealing performance of the rubber ring with different diameters of bionic dimpled was studied. The results show that the deformation of rubber ring appears prominent nonlinear characteristics when compression is increased from 1.5 mm to 2.5 ram. When the compression is 2.5 mm, the equivalent compression stress on the sealing areas of both sides of the rubber seal is greater than the working pressure of aerodynamic extinguishing cannon, which could meet the sealing requirement and would not cause leakage. So the rubber sealing ring with bionic dimpled surface possesses a good sealing characteristic and has no negative effect on the sealing of shell body; When the compression is 2.5 mm, the larger equivalent stress on the edge of sealing ring and the more even stress distribution in the high pressure area are generated due to the smaller compressive stress on the bionic dimple areas, which lays a foundation for the drag reduction characteristics of the shell body＇s rubber ring with bionic dimpled surface.展开更多
To analyze the effects of gas cannons on clouds and precipitation,multisource observational data,including those from National Centers for Environmental Prediction(NCEP)reanalysis,Hangzhou and Huzhou new-generation we...To analyze the effects of gas cannons on clouds and precipitation,multisource observational data,including those from National Centers for Environmental Prediction(NCEP)reanalysis,Hangzhou and Huzhou new-generation weather radars,laser disdrometer,ground-based automatic weather station,wind profiler radar,and Lin'an C-band dualpolarization radar,were adopted in this study.Based on the variational dual-Doppler wind retrieval method and the polarimetric variables obtained by the dual-polarization radar,we analyzed the microphysical processes and the variations in the macro-and microphysical quantities in clouds from the perspective of the synoptic background before precipitation enhancement,the polarization echo characteristics before,during and after enhancement,and the evolution of the fine three-dimensional kinematic structure and the microphysical structure.The results show that the precipitation enhancement operation promoted the development of radar echoes and prolonged their duration,and both the horizontal and vertical wind speeds increased.The dual-polarization radar echo showed that the diameter of the precipitation particles increased,and the concentration of raindrops increased after precipitation enhancement.The raindrops were lifted to a height corresponding to 0 to-20℃due to vertical updrafts.Based on the disdrometer data during precipitation enhancement,the concentration of small raindrops(lgN_(w))showed a significant increase,and the mass-weighted diameter D_(m)value decreased,indicating that the precipitation enhancement operation played a certain“lubricating”effect.After the precipitation enhancement,the concentration of raindrops did not change much compared with that during the enhancement process,while the Dm increased,corresponding to an increase in rain intensity.The results suggest the positive effect of gas cannons on precipitation enhancement.展开更多
Multiple pulmonary nodules on chest x-ray, known commonly as cannon ball secondaries, are the classical presentation of haematogenous dissemination of a malignant tumor to the lungs. This almost always indicates advan...Multiple pulmonary nodules on chest x-ray, known commonly as cannon ball secondaries, are the classical presentation of haematogenous dissemination of a malignant tumor to the lungs. This almost always indicates advanced stage of the disease with a very grim outlook in terms of cure or survival. In this report we present a patient with very extensive Cannon Ball Metastases due to advanced colonic malignancy.展开更多
ITT Industries，Cannon公司为其APD系列圆形DIN72585型连接器系列添加37路和51路产品。这种新型、引脚数更高产品专为汽车、运输和工业环境应用而设计，包括高冲击和振动应用，可减少所需连接器数量。37和51路连接器产品采用轻质、经...ITT Industries，Cannon公司为其APD系列圆形DIN72585型连接器系列添加37路和51路产品。这种新型、引脚数更高产品专为汽车、运输和工业环境应用而设计，包括高冲击和振动应用，可减少所需连接器数量。37和51路连接器产品采用轻质、经济的复合材料本体。卡口式连接器确保连接紧密和防振，连接器密封等级高达IP69K，展开更多
ITT Industries，Cannon公司新出的AJ4控制杆耐用且可靠，可使用达6百万次之多，特别适合应用于物料处理、农业及建筑仪器。它集合灵活性及高机械效能于一身，满足各种不同标准及要求。AJ4控制杆达到IP67级以上防护，符合ISO11452—2／5...ITT Industries，Cannon公司新出的AJ4控制杆耐用且可靠，可使用达6百万次之多，特别适合应用于物料处理、农业及建筑仪器。它集合灵活性及高机械效能于一身，满足各种不同标准及要求。AJ4控制杆达到IP67级以上防护，符合ISO11452—2／5，IOS7637—0及SEAJ1113／41等多种国际标准。展开更多
基金Project(51275102)supported by the National Natural Science Foundation of ChinaProject(159070220011)supported by the Science and Technology Innovative Research Programs Foundation of Harbin city,ChinaProject(HEUCF110702)supported by the Fundamental Research Funds for the Central Universities of China
文摘To solve the problem of sealing between the barrel and the rubber ring of shell body during an launching process of aerodynamic extinguishing cannon, a rubber sealing model with bionic dimpled characteristics was established based on the theory of bionic dimpled drag reduction and the principle of rubber sealing. In condition that the bionic dimpled characteristic diameters were 1, 2, 3, 4, and 5 mm, respectively, by numerical simulation, the influence of the installing compression of the rubber sealing ring on its surface stress and deformation was analyzed, and sealing performance of the rubber ring with different diameters of bionic dimpled was studied. The results show that the deformation of rubber ring appears prominent nonlinear characteristics when compression is increased from 1.5 mm to 2.5 ram. When the compression is 2.5 mm, the equivalent compression stress on the sealing areas of both sides of the rubber seal is greater than the working pressure of aerodynamic extinguishing cannon, which could meet the sealing requirement and would not cause leakage. So the rubber sealing ring with bionic dimpled surface possesses a good sealing characteristic and has no negative effect on the sealing of shell body; When the compression is 2.5 mm, the larger equivalent stress on the edge of sealing ring and the more even stress distribution in the high pressure area are generated due to the smaller compressive stress on the bionic dimple areas, which lays a foundation for the drag reduction characteristics of the shell body＇s rubber ring with bionic dimpled surface.
基金National Natural Science Foundation of China(41675029)Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX18_0998)+1 种基金Science and Technology Program of Huzhou(2021GZ14,2020GZ31)Science and Technology(Key)Program of Zhejiang Meteorological Service(2021ZD27)。
文摘To analyze the effects of gas cannons on clouds and precipitation,multisource observational data,including those from National Centers for Environmental Prediction(NCEP)reanalysis,Hangzhou and Huzhou new-generation weather radars,laser disdrometer,ground-based automatic weather station,wind profiler radar,and Lin'an C-band dualpolarization radar,were adopted in this study.Based on the variational dual-Doppler wind retrieval method and the polarimetric variables obtained by the dual-polarization radar,we analyzed the microphysical processes and the variations in the macro-and microphysical quantities in clouds from the perspective of the synoptic background before precipitation enhancement,the polarization echo characteristics before,during and after enhancement,and the evolution of the fine three-dimensional kinematic structure and the microphysical structure.The results show that the precipitation enhancement operation promoted the development of radar echoes and prolonged their duration,and both the horizontal and vertical wind speeds increased.The dual-polarization radar echo showed that the diameter of the precipitation particles increased,and the concentration of raindrops increased after precipitation enhancement.The raindrops were lifted to a height corresponding to 0 to-20℃due to vertical updrafts.Based on the disdrometer data during precipitation enhancement,the concentration of small raindrops(lgN_(w))showed a significant increase,and the mass-weighted diameter D_(m)value decreased,indicating that the precipitation enhancement operation played a certain“lubricating”effect.After the precipitation enhancement,the concentration of raindrops did not change much compared with that during the enhancement process,while the Dm increased,corresponding to an increase in rain intensity.The results suggest the positive effect of gas cannons on precipitation enhancement.
文摘Multiple pulmonary nodules on chest x-ray, known commonly as cannon ball secondaries, are the classical presentation of haematogenous dissemination of a malignant tumor to the lungs. This almost always indicates advanced stage of the disease with a very grim outlook in terms of cure or survival. In this report we present a patient with very extensive Cannon Ball Metastases due to advanced colonic malignancy.
