目的观察慢性根尖周炎根尖未闭合经口腔显微镜下生物陶瓷Iroot BP Plus联合热牙胶充填技术的治疗效果。方法选择2017年3月~2018年3月青海省西宁市口腔医院收治的慢性根尖周炎根尖未闭合患者120例,根据随机数字表法分为对照组与研究组,每...目的观察慢性根尖周炎根尖未闭合经口腔显微镜下生物陶瓷Iroot BP Plus联合热牙胶充填技术的治疗效果。方法选择2017年3月~2018年3月青海省西宁市口腔医院收治的慢性根尖周炎根尖未闭合患者120例,根据随机数字表法分为对照组与研究组,每组60例。两组均接受口腔显微镜下生物陶瓷Iroot BP Plus根尖屏障术治疗,研究组在此基础上联合热牙胶垂直加压充填术。术后1年评价临床疗效;比较两组操作时间、疼痛持续时间;分别于治疗前、治疗2周后,检测龈沟液炎性因子水平;比较两组患牙保留率。结果研究组治疗总有效率高于对照组,患牙保留率高于对照组(P<0.05)。两组操作时间比较,差异无统计学意义(P>0.05)。研究组术后疼痛持续时间短于对照组(P<0.05)。治疗前两组龈沟液炎性因子比较,差异无统计学意义(P>0.05);治疗2周后,两组龈沟液炎性因子水平低于治疗前,且研究组低于对照组(均P<0.05)。结论口腔显微镜下生物陶瓷Iroot BP Plus联合热牙胶充填技术治疗慢性根尖周炎根尖未闭合,可缩短患者术后疼痛持续时间,提高患牙保留率,患者根尖炎症消除效果好。展开更多
Floor heave is the most common convergence in gob-side entry retaining.The paper analyzes the form,process and characteristics of gob-side entry retaining with the comprehensive methods of theoretical analysis,numeric...Floor heave is the most common convergence in gob-side entry retaining.The paper analyzes the form,process and characteristics of gob-side entry retaining with the comprehensive methods of theoretical analysis,numerical simulation and the field trial.Research results present that bending and folding floor heave is the main factor in the stage of the first panel mining;squeezing and fluidity floor heave plays a great role in the stable stage of gob-side entry retaining;the combination of the former two factors affects mainly the stage of the second mining ahead;abutment pressure is a fundamental contribution to the serious floor heave of gob-side entry retaining,and sides corners of solid coal body are key part in the case of floor heave controlling of gob-side entry retaining.Floor heave of gob-side entry retaining can be significantly controlled by reinforcing sides and corners of solid coal body,and influence rules on the floor heave of gob side entry retaining of sides supporting strength and the bottom bolt orientation in solid coal side are obtained.Research results have been successfully applied in gob-side entry retaining of G20-F23070 face haulage roadway in #2 coal mine of Pingmei Group,and the field observation shows that the proposed technique is an effective way in controlling the floor heave of gob-side entry retaining.展开更多
In the artificial intelligence age,multifunctional and intelligent fireproof fabric-based electronics are urgently needed.Herein,a novel thread-shaped all-fabric-based piezoresistive sensor(denoted as TAFPS)with prope...In the artificial intelligence age,multifunctional and intelligent fireproof fabric-based electronics are urgently needed.Herein,a novel thread-shaped all-fabric-based piezoresistive sensor(denoted as TAFPS)with properties such as flame retardancy,firewarning,and piezoresistivity is proposed,which is composed of an inner nickel-plated fabric electrode,a multifunctional double helix fabric,and an external flame-retardant encapsulation fabric.Owing to the multiple flame-retardant properties of glass fiber tubular fabric,aminated carbon nanotubes(ACNTs),and ammonium polyphosphate,the char residue of the TAFPS reaches40.3 wt%at 800℃.In addition,the heat-sensitive effect of ACNTs during combustion causes a rapid decrease in the TAFPS resistance,triggering the fire alarm system within 2 s.Additionally,benefiting from the force-sensitive behavior of the double helix layer and tightly wrapped pattern of the external heat-shrinkable tubular fabric,TAFPS demonstrated a high sensitivity of4.40 kPa^(-1)(0–5.81 k Pa)and good stability for 10000 s.Considering its excellent flame resistance,high sensitivity,and agreeable stability,the developed TAFPS can be integrated into fire suits to monitor the exercise training process and the external fire environment.This work offers a novel approach for fabricating all-fabric-based piezoresistive sensors in the future for fire prevention and fire alarms,with promising applications in fire protection,the Internet of Things,and smart apparel.展开更多
文摘目的观察慢性根尖周炎根尖未闭合经口腔显微镜下生物陶瓷Iroot BP Plus联合热牙胶充填技术的治疗效果。方法选择2017年3月~2018年3月青海省西宁市口腔医院收治的慢性根尖周炎根尖未闭合患者120例,根据随机数字表法分为对照组与研究组,每组60例。两组均接受口腔显微镜下生物陶瓷Iroot BP Plus根尖屏障术治疗,研究组在此基础上联合热牙胶垂直加压充填术。术后1年评价临床疗效;比较两组操作时间、疼痛持续时间;分别于治疗前、治疗2周后,检测龈沟液炎性因子水平;比较两组患牙保留率。结果研究组治疗总有效率高于对照组,患牙保留率高于对照组(P<0.05)。两组操作时间比较,差异无统计学意义(P>0.05)。研究组术后疼痛持续时间短于对照组(P<0.05)。治疗前两组龈沟液炎性因子比较,差异无统计学意义(P>0.05);治疗2周后,两组龈沟液炎性因子水平低于治疗前,且研究组低于对照组(均P<0.05)。结论口腔显微镜下生物陶瓷Iroot BP Plus联合热牙胶充填技术治疗慢性根尖周炎根尖未闭合,可缩短患者术后疼痛持续时间,提高患牙保留率,患者根尖炎症消除效果好。
基金provided by the National Natural Science Foundation of China(No.51174195)the State Key Laboratory of Coal Resources and Mine Safety of China University of Mining and Technology(No.SKLCRSM08X04)+1 种基金a foundation for the author of the National Excellent Doctoral Dissertation of China(No.200760)the Science Research Fund of China University of Mining and Technology(No.2008A002)
文摘Floor heave is the most common convergence in gob-side entry retaining.The paper analyzes the form,process and characteristics of gob-side entry retaining with the comprehensive methods of theoretical analysis,numerical simulation and the field trial.Research results present that bending and folding floor heave is the main factor in the stage of the first panel mining;squeezing and fluidity floor heave plays a great role in the stable stage of gob-side entry retaining;the combination of the former two factors affects mainly the stage of the second mining ahead;abutment pressure is a fundamental contribution to the serious floor heave of gob-side entry retaining,and sides corners of solid coal body are key part in the case of floor heave controlling of gob-side entry retaining.Floor heave of gob-side entry retaining can be significantly controlled by reinforcing sides and corners of solid coal body,and influence rules on the floor heave of gob side entry retaining of sides supporting strength and the bottom bolt orientation in solid coal side are obtained.Research results have been successfully applied in gob-side entry retaining of G20-F23070 face haulage roadway in #2 coal mine of Pingmei Group,and the field observation shows that the proposed technique is an effective way in controlling the floor heave of gob-side entry retaining.
基金supported by the National Natural Science Foundation of China(Grant No.52175554)Young Top Talent Project of the Hebei Provincial Department of Education(Grant No.BJK2023116)+2 种基金the Central Guiding Local Science and Technology Development Fund Project(Grant No.236Z4901G)the Natural Science Foundation of Hebei Province(Grant No.F2021409007)the School Research Fund Project(Grant No.YKY-2023-34)。
文摘In the artificial intelligence age,multifunctional and intelligent fireproof fabric-based electronics are urgently needed.Herein,a novel thread-shaped all-fabric-based piezoresistive sensor(denoted as TAFPS)with properties such as flame retardancy,firewarning,and piezoresistivity is proposed,which is composed of an inner nickel-plated fabric electrode,a multifunctional double helix fabric,and an external flame-retardant encapsulation fabric.Owing to the multiple flame-retardant properties of glass fiber tubular fabric,aminated carbon nanotubes(ACNTs),and ammonium polyphosphate,the char residue of the TAFPS reaches40.3 wt%at 800℃.In addition,the heat-sensitive effect of ACNTs during combustion causes a rapid decrease in the TAFPS resistance,triggering the fire alarm system within 2 s.Additionally,benefiting from the force-sensitive behavior of the double helix layer and tightly wrapped pattern of the external heat-shrinkable tubular fabric,TAFPS demonstrated a high sensitivity of4.40 kPa^(-1)(0–5.81 k Pa)and good stability for 10000 s.Considering its excellent flame resistance,high sensitivity,and agreeable stability,the developed TAFPS can be integrated into fire suits to monitor the exercise training process and the external fire environment.This work offers a novel approach for fabricating all-fabric-based piezoresistive sensors in the future for fire prevention and fire alarms,with promising applications in fire protection,the Internet of Things,and smart apparel.
