A ternary early-strengthening agent consisting of calcium formate+triethanolamine+lithium sulfate was compounded with quercetin to shorten the setting time of cementitious materials while ensuring their early strength...A ternary early-strengthening agent consisting of calcium formate+triethanolamine+lithium sulfate was compounded with quercetin to shorten the setting time of cementitious materials while ensuring their early strength.The optimum ratio of the three early-strengthening agents was determined as 0.5%calcium formate+0.04%triethanolamine+0.4%lithium sulfate by response surface methodology.The effects of the ternary early-strengthening agent composed of calcium formate+triethanolamine(TEA)+lithium sulfate on cementitious pore sealing materials under the synergistic effect of quercetin were studied by means of the performance tests of compressive strength,fluidity,and setting time,and the microstructural characterizations of X-ray powder diffractometer(XRD),thermogravimetry(TG-DSC)and scanning electron microscopy(SEM).The study shows that the synergistic effect of ternary early-strengthening agent and quercetin forms a multi-performance composite admixture for cementitious materials.The best performance was obtained with the compounding scheme of 0.5%calcium formate+0.04%triethanolamine+0.4%lithium sulfate ternary early-strengthening agent and 0.05%quercetin.The compressive strength of 1,3,7,and 28 d are 94.8%,39.8%,42%,and 28%higher than those of the blank group,respectively.The initial time and final setting time are 41 and 57 minutes,respectively.According to the microscopic analysis,the network and fibrous C-S-H gels generated by ternary early-strengthening agents are attached to the surface promoted by quercetin,which forms skeleton support while thickening and solidifying the cement slurry,which enhances the early compressive strength of the cement-based materials.展开更多
目的 探讨酶联免疫法和金标法对HIV抗体的检测结果,明确针对艾滋病更为有效的临床筛查手段。方法选取264例疑似艾滋病患者,采集入组患者静脉血并进行酶联免疫法与金标法检测HIV抗体。以临床诊断结果为准,比较酶联免疫法和金标法与临床...目的 探讨酶联免疫法和金标法对HIV抗体的检测结果,明确针对艾滋病更为有效的临床筛查手段。方法选取264例疑似艾滋病患者,采集入组患者静脉血并进行酶联免疫法与金标法检测HIV抗体。以临床诊断结果为准,比较酶联免疫法和金标法与临床检查结果的一致性;比较酶联免疫法和金标法对艾滋病的诊断效能。结果 264例疑似艾滋病患者中,经临床筛查试验和确证试验确诊225例。κ检验分析结果显示,酶联免疫法检查结果与临床诊断结果具有高度一致性(κ=0.897, P <0.05);金标法检查结果与临床诊断结果具有高度一致性(κ=0.902, P <0.05)。酶联免疫法与金标法诊断艾滋病的灵敏度、特异性与准确率比较,差异均无统计学意义(P>0.05)。结论 酶联免疫法和金标法对HIV抗体均具有较好的检出效果,可为艾滋病临床诊断提供较为准确的数据参考,临床检测中可根据患者自身情况选择相应的检测方法,必要时还可进行联合检测。展开更多
From almost nothing in the 1970s,Shenzhen today has emerged as a thriving trade and innovation hub,pioneering the country’s innovative development.IN the 1990s,one of the most popular songs in China was The story of ...From almost nothing in the 1970s,Shenzhen today has emerged as a thriving trade and innovation hub,pioneering the country’s innovative development.IN the 1990s,one of the most popular songs in China was The story of spring,a tribute to the country’s reform and opening-up started in 1978 that ushered in a new“spring”of growth in China.One of the decisions taken at that time was to develop a county in southern China into a pilot for many of the reforms to be implemented.The county was the predecessor of today’s metropolis Shenzhen,a thriving industrial hub boasting many firsts.展开更多
基金Funded by the Key Technologies Research and Development Program(No.2021YFC28000900)the National Natural Science Foundation of China(No.52374178)the Collaborative Innovation Project of Colleges and Universities of Anhui Province(No.GXXT-2020-057)。
文摘A ternary early-strengthening agent consisting of calcium formate+triethanolamine+lithium sulfate was compounded with quercetin to shorten the setting time of cementitious materials while ensuring their early strength.The optimum ratio of the three early-strengthening agents was determined as 0.5%calcium formate+0.04%triethanolamine+0.4%lithium sulfate by response surface methodology.The effects of the ternary early-strengthening agent composed of calcium formate+triethanolamine(TEA)+lithium sulfate on cementitious pore sealing materials under the synergistic effect of quercetin were studied by means of the performance tests of compressive strength,fluidity,and setting time,and the microstructural characterizations of X-ray powder diffractometer(XRD),thermogravimetry(TG-DSC)and scanning electron microscopy(SEM).The study shows that the synergistic effect of ternary early-strengthening agent and quercetin forms a multi-performance composite admixture for cementitious materials.The best performance was obtained with the compounding scheme of 0.5%calcium formate+0.04%triethanolamine+0.4%lithium sulfate ternary early-strengthening agent and 0.05%quercetin.The compressive strength of 1,3,7,and 28 d are 94.8%,39.8%,42%,and 28%higher than those of the blank group,respectively.The initial time and final setting time are 41 and 57 minutes,respectively.According to the microscopic analysis,the network and fibrous C-S-H gels generated by ternary early-strengthening agents are attached to the surface promoted by quercetin,which forms skeleton support while thickening and solidifying the cement slurry,which enhances the early compressive strength of the cement-based materials.
文摘目的 探讨酶联免疫法和金标法对HIV抗体的检测结果,明确针对艾滋病更为有效的临床筛查手段。方法选取264例疑似艾滋病患者,采集入组患者静脉血并进行酶联免疫法与金标法检测HIV抗体。以临床诊断结果为准,比较酶联免疫法和金标法与临床检查结果的一致性;比较酶联免疫法和金标法对艾滋病的诊断效能。结果 264例疑似艾滋病患者中,经临床筛查试验和确证试验确诊225例。κ检验分析结果显示,酶联免疫法检查结果与临床诊断结果具有高度一致性(κ=0.897, P <0.05);金标法检查结果与临床诊断结果具有高度一致性(κ=0.902, P <0.05)。酶联免疫法与金标法诊断艾滋病的灵敏度、特异性与准确率比较,差异均无统计学意义(P>0.05)。结论 酶联免疫法和金标法对HIV抗体均具有较好的检出效果,可为艾滋病临床诊断提供较为准确的数据参考,临床检测中可根据患者自身情况选择相应的检测方法,必要时还可进行联合检测。
文摘From almost nothing in the 1970s,Shenzhen today has emerged as a thriving trade and innovation hub,pioneering the country’s innovative development.IN the 1990s,one of the most popular songs in China was The story of spring,a tribute to the country’s reform and opening-up started in 1978 that ushered in a new“spring”of growth in China.One of the decisions taken at that time was to develop a county in southern China into a pilot for many of the reforms to be implemented.The county was the predecessor of today’s metropolis Shenzhen,a thriving industrial hub boasting many firsts.
