Although magnetotelluric sounding method applied to the land is advanced, there are many difficulties when it is applied to marine environment, one of which is how to lay magnetic field sensors down to the seafloor to...Although magnetotelluric sounding method applied to the land is advanced, there are many difficulties when it is applied to marine environment, one of which is how to lay magnetic field sensors down to the seafloor to complete measurements. To protect the magnetic field sensors from intense erosion and high pressure, suitable high-pressure sealed cabins must be designed to load them. For the consideration of magnetic measurement and marine operation, the sealed pressure cabin should be nonmagnetic and transportable. Among all optional materials, LC4 super.hard aluminum alloy has the highest performance of price/quality ratio to make the sealed pressure cabin. However, it does not mean that the high-pressure sealed cabin made using LC4 will be perfect in performance. In fact, because of its weak magnetism, the pressure cabin made using LC4 has distorting effect on frequency responses of the magnetic field sensors sealed in it. This distorting effect does not affect the use of the magnetic field sensor, but if we want to eliminate its effect, we should study it by experimental measurements. In our experiment tests, frequency sweep magnetic field as excitation signal was used, and then responses of the magnetic field sensor before and after being loaded into the high-pressure sealed cabin were measured. Finally, normalized abnormal curves for the frequency responses were obtained, through which we could show how the high-pressure sealed cabin produces effects on the responses of the magnetic field sensor. Experimental results suggest that the response distortion induced by the sealed pressure cabin appears on mid- and high-frequency areas. Using experimental results as standardization data, the frequency responses collected from seafloor magnetotelluric measurements can be corrected to restore real information about the seafloor field source.展开更多
To explore the feasibility of the full automatic animal experimental cabin to establish the animal models in normobaric/hypobaric hypoxic and high carbon dioxide environment. Methods： Sixty SPF-class male DS rats wer...To explore the feasibility of the full automatic animal experimental cabin to establish the animal models in normobaric/hypobaric hypoxic and high carbon dioxide environment. Methods： Sixty SPF-class male DS rats were divided into 2 groups, 20 for normobaric, hypoxic conditions and the other 40 for hypobaric, hypoxic conditions. For each group, the pulmonary arterial pressure and carotid arterial pressure indicators of rats were examined by using the physiological multi-detector, and the pulmonary vascular changes in the structure were observed. Results： The normobaric/hypobaric hypoxic with high carbon dioxide environment can promote the formation of pulmonary hypertension and accelerate changes in pulmonary vascular remodeling, and promote the right ventricular hypertrophy. Conclusion： Clinical applications showed that the animal experimental cabin has observed and controlled accurately. The result was safe, reliable and reproducible. The cabin can successfully establish the pulmonary hypertension model in normobaric/hypobaric hypoxic with high carbon dioxide environment, and in order to study the physiological mechanism of a variety of circulation and respiratory diseases caused by lack of oxygen, which provided an experimental technology platform for clinical research.展开更多
为考核装甲车辆用防爆复合结构的抗爆性能,提出了基于底甲板损伤等级和(AIS)人体伤害/防护等级为防爆判据的台架试验方法和模拟舱体试验方法。建立了防爆复合结构抗6 kg TNT当量的试验平台,并进行了防爆复合结构抗6 kg TNT当量爆炸性能...为考核装甲车辆用防爆复合结构的抗爆性能,提出了基于底甲板损伤等级和(AIS)人体伤害/防护等级为防爆判据的台架试验方法和模拟舱体试验方法。建立了防爆复合结构抗6 kg TNT当量的试验平台,并进行了防爆复合结构抗6 kg TNT当量爆炸性能验证试验。台架试验后基板的稳态变形量为47.451 mm,模拟舱体试验后舱内模拟假人各项关键部位测试结果均在指标范围内,这表明该防爆复合结构具有良好的抗爆性能,对装甲车辆底甲板具有一定的保护作用,并且能够有效保护模拟舱体内部人员。此外,上述试验结果还表明,提出的台架试验方法和模拟舱体试验方法能够较好地考核和评价装甲车辆用防爆复合结构的抗爆性能。展开更多
在空间较封闭的舱室中发生爆炸时,舱室板架结构所承受的载荷包括壁面反射冲击波和角隅部位的汇聚冲击波,这种载荷特性将直接影响到结构的破坏形式。采用双层舱室结构模型进行了不同装药量的舱内爆炸实验,研究了三种不同的角隅连接结构...在空间较封闭的舱室中发生爆炸时,舱室板架结构所承受的载荷包括壁面反射冲击波和角隅部位的汇聚冲击波,这种载荷特性将直接影响到结构的破坏形式。采用双层舱室结构模型进行了不同装药量的舱内爆炸实验,研究了三种不同的角隅连接结构型式对冲击波在角隅汇聚情况的影响。基于图象法(Method of Images)解释了冲击波在角隅的汇聚现象,采用数值计算方法分析舱内爆炸冲击载荷与结构的相互作用。结果表明:舱室角隅位置的连接结构型式只对小药量工况下的舱内爆炸冲击波流场有一定的影响,其中相对平缓过渡连接的结构型式一定程度上减缓了冲击波在角隅的汇聚。当初始冲击波强度较大时,结构型式的改变对冲击波的角隅汇聚影响不大。舱室内形成的反射冲击波高压区将首先作用在横舱壁中部位置,基于这种传播路径和特性,横舱壁上设置适当的开孔将有效地降低舱内的冲击波汇聚压力。展开更多
基金This paper is supported by the National "863" Program in the Tenth Five-Year-Plan (No. 2002AA615020)Eleventh Five-Year-Plan (No. 2006AA09A201)the Focused Subject Program of Beijing (No. XK104910598).
文摘Although magnetotelluric sounding method applied to the land is advanced, there are many difficulties when it is applied to marine environment, one of which is how to lay magnetic field sensors down to the seafloor to complete measurements. To protect the magnetic field sensors from intense erosion and high pressure, suitable high-pressure sealed cabins must be designed to load them. For the consideration of magnetic measurement and marine operation, the sealed pressure cabin should be nonmagnetic and transportable. Among all optional materials, LC4 super.hard aluminum alloy has the highest performance of price/quality ratio to make the sealed pressure cabin. However, it does not mean that the high-pressure sealed cabin made using LC4 will be perfect in performance. In fact, because of its weak magnetism, the pressure cabin made using LC4 has distorting effect on frequency responses of the magnetic field sensors sealed in it. This distorting effect does not affect the use of the magnetic field sensor, but if we want to eliminate its effect, we should study it by experimental measurements. In our experiment tests, frequency sweep magnetic field as excitation signal was used, and then responses of the magnetic field sensor before and after being loaded into the high-pressure sealed cabin were measured. Finally, normalized abnormal curves for the frequency responses were obtained, through which we could show how the high-pressure sealed cabin produces effects on the responses of the magnetic field sensor. Experimental results suggest that the response distortion induced by the sealed pressure cabin appears on mid- and high-frequency areas. Using experimental results as standardization data, the frequency responses collected from seafloor magnetotelluric measurements can be corrected to restore real information about the seafloor field source.
文摘To explore the feasibility of the full automatic animal experimental cabin to establish the animal models in normobaric/hypobaric hypoxic and high carbon dioxide environment. Methods： Sixty SPF-class male DS rats were divided into 2 groups, 20 for normobaric, hypoxic conditions and the other 40 for hypobaric, hypoxic conditions. For each group, the pulmonary arterial pressure and carotid arterial pressure indicators of rats were examined by using the physiological multi-detector, and the pulmonary vascular changes in the structure were observed. Results： The normobaric/hypobaric hypoxic with high carbon dioxide environment can promote the formation of pulmonary hypertension and accelerate changes in pulmonary vascular remodeling, and promote the right ventricular hypertrophy. Conclusion： Clinical applications showed that the animal experimental cabin has observed and controlled accurately. The result was safe, reliable and reproducible. The cabin can successfully establish the pulmonary hypertension model in normobaric/hypobaric hypoxic with high carbon dioxide environment, and in order to study the physiological mechanism of a variety of circulation and respiratory diseases caused by lack of oxygen, which provided an experimental technology platform for clinical research.
文摘为考核装甲车辆用防爆复合结构的抗爆性能,提出了基于底甲板损伤等级和(AIS)人体伤害/防护等级为防爆判据的台架试验方法和模拟舱体试验方法。建立了防爆复合结构抗6 kg TNT当量的试验平台,并进行了防爆复合结构抗6 kg TNT当量爆炸性能验证试验。台架试验后基板的稳态变形量为47.451 mm,模拟舱体试验后舱内模拟假人各项关键部位测试结果均在指标范围内,这表明该防爆复合结构具有良好的抗爆性能,对装甲车辆底甲板具有一定的保护作用,并且能够有效保护模拟舱体内部人员。此外,上述试验结果还表明,提出的台架试验方法和模拟舱体试验方法能够较好地考核和评价装甲车辆用防爆复合结构的抗爆性能。
文摘在空间较封闭的舱室中发生爆炸时,舱室板架结构所承受的载荷包括壁面反射冲击波和角隅部位的汇聚冲击波,这种载荷特性将直接影响到结构的破坏形式。采用双层舱室结构模型进行了不同装药量的舱内爆炸实验,研究了三种不同的角隅连接结构型式对冲击波在角隅汇聚情况的影响。基于图象法(Method of Images)解释了冲击波在角隅的汇聚现象,采用数值计算方法分析舱内爆炸冲击载荷与结构的相互作用。结果表明:舱室角隅位置的连接结构型式只对小药量工况下的舱内爆炸冲击波流场有一定的影响,其中相对平缓过渡连接的结构型式一定程度上减缓了冲击波在角隅的汇聚。当初始冲击波强度较大时,结构型式的改变对冲击波的角隅汇聚影响不大。舱室内形成的反射冲击波高压区将首先作用在横舱壁中部位置,基于这种传播路径和特性,横舱壁上设置适当的开孔将有效地降低舱内的冲击波汇聚压力。
