<p align="justify"> <span style="font-family:Verdana;">Amid the Covid-19 widespread, it has been challenging for educational institutions to conduct online classes, facing multiples cha...<p align="justify"> <span style="font-family:Verdana;">Amid the Covid-19 widespread, it has been challenging for educational institutions to conduct online classes, facing multiples challenges. This paper provides an insight into different approaches in facing those challenges which includes conducting a fair online class for students. It is tough for an instructor to keep track of their students at the same time because it is difficult to screen if any of the understudies within the class are not present, mindful, or drowsing. This paper discusses a possible solution, something new that can offer support to instructors seeing things from a more significant point of view. The solution is a facial analysis computer program that can let instructors know which students are attentive and who is not. There’s a green and red square box for face detection, for which Instructors can watch by seeing a green box on those mindful students conjointly, a red box on those who are not mindful at all. This paper finds that the program can automatically give attendance by analyzing data from face detection. It has other features for which the teacher can also know if any student leaves the class early. In this paper, model design, performance analysis, and online class assistant aspects of the program have been discussed.</span> </p>展开更多
建立了在线液相色谱-二极管阵列检测器-串联质谱技术(LC-DAD-MS/MS)同时测定野生菌中多肽类蘑菇毒素(鹅膏毒肽和鬼笔毒肽)的分析方法。样品经甲醇提取,水稀释后,在碱性条件下用XBridge^(TM) BEH C_(18)柱(150m m×3.0 m m,2.5μm)分...建立了在线液相色谱-二极管阵列检测器-串联质谱技术(LC-DAD-MS/MS)同时测定野生菌中多肽类蘑菇毒素(鹅膏毒肽和鬼笔毒肽)的分析方法。样品经甲醇提取,水稀释后,在碱性条件下用XBridge^(TM) BEH C_(18)柱(150m m×3.0 m m,2.5μm)分离,并先后用DAD和MS/MS检测。使用碱性流动相能够实现5种多肽类蘑菇毒素在15 m in内达到基线分离,同时又能有效抑制质谱加钠峰[M+Na]^+的响应信号,保证检测的稳定性和灵敏度。5种蘑菇毒素在0.05~500 mg/kg范围内线性关系良好,相关系数(r)>0.99;检出限为0.005~0.02 mg/kg。通过实际样品检测,证明该法操作简单、快速,灵敏度高,宽的定量检测线性范围能满足实际样品中蘑菇毒素含量变化大的特点。展开更多
目的验证设计改进的光催化涂层净化气态有机物能力评价系统,使所设计的光催化评价系统可以准确地表征光催化涂层对如文章中所述0.25μL/L体积浓度级别的微量苯气体的降解情况。方法首次采用PID光离子化检测器在线监测污染物降解效率,并...目的验证设计改进的光催化涂层净化气态有机物能力评价系统,使所设计的光催化评价系统可以准确地表征光催化涂层对如文章中所述0.25μL/L体积浓度级别的微量苯气体的降解情况。方法首次采用PID光离子化检测器在线监测污染物降解效率,并进行了适当的材料及工艺上的改进。实验以两种TiO_2光触媒涂层样品为对象,以苯作为污染物,进行了一系列性能表征实验。结果评价系统性能良好,可以准确地反应出在5~20 W/m^2可见光辐照下,两种不同光触媒涂层样品的光催化效率分别为11.7%~57.3%以及13.4%~67.4%。在实验考察的体积浓度范围0.05~0.4μL/L内,污染物浓度的变化对降解效率影响不大,而随着污染气体流速从30 m L/min增加至90 m L/min,两种涂层对污染物的降解效率变差,分别从43.6%降低到25.9%以及从52.9%降低到29.9%。结论研究设计的光催化涂层评价系统精密准确稳定,其较高的检出限能够很好地满足光催化材料对痕量气态有机污染物降解情况表征的需要,可广泛用于光催化领域气-固两相反应的科学研究及产品评价。展开更多
文摘<p align="justify"> <span style="font-family:Verdana;">Amid the Covid-19 widespread, it has been challenging for educational institutions to conduct online classes, facing multiples challenges. This paper provides an insight into different approaches in facing those challenges which includes conducting a fair online class for students. It is tough for an instructor to keep track of their students at the same time because it is difficult to screen if any of the understudies within the class are not present, mindful, or drowsing. This paper discusses a possible solution, something new that can offer support to instructors seeing things from a more significant point of view. The solution is a facial analysis computer program that can let instructors know which students are attentive and who is not. There’s a green and red square box for face detection, for which Instructors can watch by seeing a green box on those mindful students conjointly, a red box on those who are not mindful at all. This paper finds that the program can automatically give attendance by analyzing data from face detection. It has other features for which the teacher can also know if any student leaves the class early. In this paper, model design, performance analysis, and online class assistant aspects of the program have been discussed.</span> </p>
文摘建立了在线液相色谱-二极管阵列检测器-串联质谱技术(LC-DAD-MS/MS)同时测定野生菌中多肽类蘑菇毒素(鹅膏毒肽和鬼笔毒肽)的分析方法。样品经甲醇提取,水稀释后,在碱性条件下用XBridge^(TM) BEH C_(18)柱(150m m×3.0 m m,2.5μm)分离,并先后用DAD和MS/MS检测。使用碱性流动相能够实现5种多肽类蘑菇毒素在15 m in内达到基线分离,同时又能有效抑制质谱加钠峰[M+Na]^+的响应信号,保证检测的稳定性和灵敏度。5种蘑菇毒素在0.05~500 mg/kg范围内线性关系良好,相关系数(r)>0.99;检出限为0.005~0.02 mg/kg。通过实际样品检测,证明该法操作简单、快速,灵敏度高,宽的定量检测线性范围能满足实际样品中蘑菇毒素含量变化大的特点。
文摘目的验证设计改进的光催化涂层净化气态有机物能力评价系统,使所设计的光催化评价系统可以准确地表征光催化涂层对如文章中所述0.25μL/L体积浓度级别的微量苯气体的降解情况。方法首次采用PID光离子化检测器在线监测污染物降解效率,并进行了适当的材料及工艺上的改进。实验以两种TiO_2光触媒涂层样品为对象,以苯作为污染物,进行了一系列性能表征实验。结果评价系统性能良好,可以准确地反应出在5~20 W/m^2可见光辐照下,两种不同光触媒涂层样品的光催化效率分别为11.7%~57.3%以及13.4%~67.4%。在实验考察的体积浓度范围0.05~0.4μL/L内,污染物浓度的变化对降解效率影响不大,而随着污染气体流速从30 m L/min增加至90 m L/min,两种涂层对污染物的降解效率变差,分别从43.6%降低到25.9%以及从52.9%降低到29.9%。结论研究设计的光催化涂层评价系统精密准确稳定,其较高的检出限能够很好地满足光催化材料对痕量气态有机污染物降解情况表征的需要,可广泛用于光催化领域气-固两相反应的科学研究及产品评价。