The woven basalt fiber composites(WBFC) and the unidirectional [0°/90°/45°/-45°]s basalt fiber composites(UBFC) were prepared by hot-pressing.Three-point bending test,low velocity impact test,and b...The woven basalt fiber composites(WBFC) and the unidirectional [0°/90°/45°/-45°]s basalt fiber composites(UBFC) were prepared by hot-pressing.Three-point bending test,low velocity impact test,and ballistic test were performed to the prepared composites.After the tests,the specimens were recovered and analyzed for micromorphology.Three-point bending tests show that both the bending strength and stiffness of the WBFC surpass those of the UBFC.Low velocity impact test results show that the low velocity impact resistance to hemispherical impactor of the UBFC is higher than that of the WBFC,but the low velocity impact resistance to sharp impactor of the UBFC is lower than that of the WBFC.For the ballistic test,it can be found that the ballistic property of the UBFC is higher than that of the WBFC. After the tests,microscopic analysis of the specimens was applied,and their failure mechanism was discussed.The main failure modes of the UBFC are delamination and fibers breakage under the above loading conditions while the main failure mode of the WBFC is fibers breakage.Although delamination damage can be found in the WBFC under the above loading conditions,the degree of delamination is far less than that of the UBFC.展开更多
目的：评估老年性聋患者噪声下言语识别能力，探讨年龄、听力损失程度、认知功能对噪声下言语识别能力的影响。方法以90例60岁以上老年性聋者为受试者，按年龄分为三组，60～69岁（44例88耳）、70～79岁（32例64耳）、＞79岁（14例28耳...目的：评估老年性聋患者噪声下言语识别能力，探讨年龄、听力损失程度、认知功能对噪声下言语识别能力的影响。方法以90例60岁以上老年性聋者为受试者，按年龄分为三组，60～69岁（44例88耳）、70～79岁（32例64耳）、＞79岁（14例28耳），完成纯音听阈测试、普通话噪声下言语测试（Mandarin hearing in noise test ， MHINT）及简易智能精神状态量表（mini－mental state examination ，MMSE）评估，分别获得0．5、1、2、4 kHz平均听阈、MHINT自适应信噪比及MMSE量表总得分；分析年龄、平均听阈、自适应信噪比及MMSE量表得分之间的相关性。结果①平均听阈、M HINT信噪比随年龄增长而提高，不同年龄组间的平均听阈、M HINT 信噪比差异有统计学意义（P＜0．01）；②不同程度听力损失组间的M HINT信噪比差异显著（P＜0．01），控制认知得分的情况下其差异仍然有统计学意义（P＜0．01），且平均听阈与 MHINT 信噪比具有显著的直线相关性（r＝0．326，P＜0．01），随着受试者平均听阈提高，MMSE得分下降，二者有直线相关性（r＝－0．187，P＜0．05）；③MHINT信噪比与MMSE量表得分具有相关性（r＝－0．201，P＜0．01），认知功能减退组（＜27分）的MHINT信噪比平均值较认知功能正常组（27～30分）显著增加（P＜0．01）；不同听力损失程度组中，认知功能正常组与减退组之间M HINT信噪比差异无统计学意义（P＞0．05）。结论噪声下言语测试可用于老年人听觉功能评估，老年性聋者的年龄、听力损失程度、认知功能与噪声下言语识别能力之间相互影响，评估老年人听觉功能时应考虑认知功能的影响。展开更多
基金supported by the National Science Foundation of China(No.51571033)supported in part by the National Natural Science Foundation of China under Grant No.11521062。
文摘The woven basalt fiber composites(WBFC) and the unidirectional [0°/90°/45°/-45°]s basalt fiber composites(UBFC) were prepared by hot-pressing.Three-point bending test,low velocity impact test,and ballistic test were performed to the prepared composites.After the tests,the specimens were recovered and analyzed for micromorphology.Three-point bending tests show that both the bending strength and stiffness of the WBFC surpass those of the UBFC.Low velocity impact test results show that the low velocity impact resistance to hemispherical impactor of the UBFC is higher than that of the WBFC,but the low velocity impact resistance to sharp impactor of the UBFC is lower than that of the WBFC.For the ballistic test,it can be found that the ballistic property of the UBFC is higher than that of the WBFC. After the tests,microscopic analysis of the specimens was applied,and their failure mechanism was discussed.The main failure modes of the UBFC are delamination and fibers breakage under the above loading conditions while the main failure mode of the WBFC is fibers breakage.Although delamination damage can be found in the WBFC under the above loading conditions,the degree of delamination is far less than that of the UBFC.
文摘目的：评估老年性聋患者噪声下言语识别能力，探讨年龄、听力损失程度、认知功能对噪声下言语识别能力的影响。方法以90例60岁以上老年性聋者为受试者，按年龄分为三组，60～69岁（44例88耳）、70～79岁（32例64耳）、＞79岁（14例28耳），完成纯音听阈测试、普通话噪声下言语测试（Mandarin hearing in noise test ， MHINT）及简易智能精神状态量表（mini－mental state examination ，MMSE）评估，分别获得0．5、1、2、4 kHz平均听阈、MHINT自适应信噪比及MMSE量表总得分；分析年龄、平均听阈、自适应信噪比及MMSE量表得分之间的相关性。结果①平均听阈、M HINT信噪比随年龄增长而提高，不同年龄组间的平均听阈、M HINT 信噪比差异有统计学意义（P＜0．01）；②不同程度听力损失组间的M HINT信噪比差异显著（P＜0．01），控制认知得分的情况下其差异仍然有统计学意义（P＜0．01），且平均听阈与 MHINT 信噪比具有显著的直线相关性（r＝0．326，P＜0．01），随着受试者平均听阈提高，MMSE得分下降，二者有直线相关性（r＝－0．187，P＜0．05）；③MHINT信噪比与MMSE量表得分具有相关性（r＝－0．201，P＜0．01），认知功能减退组（＜27分）的MHINT信噪比平均值较认知功能正常组（27～30分）显著增加（P＜0．01）；不同听力损失程度组中，认知功能正常组与减退组之间M HINT信噪比差异无统计学意义（P＞0．05）。结论噪声下言语测试可用于老年人听觉功能评估，老年性聋者的年龄、听力损失程度、认知功能与噪声下言语识别能力之间相互影响，评估老年人听觉功能时应考虑认知功能的影响。
