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纳米钛酸钡颗粒砂磨分散工艺研究
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作者 敖宏 彭文 《佛山陶瓷》 2023年第1期79-81,共3页
本文研究了使用砂磨机进行纳米颗粒分散时的流量设定和磨球选择。为了确保砂磨过程中磨球不会逸出或者聚集在砂磨机的一端,浆料在研磨腔体中的上升速度应小于浆料液面上升速度,因此使用不同粒径的磨球都有最大限制流量。研磨过程的分散... 本文研究了使用砂磨机进行纳米颗粒分散时的流量设定和磨球选择。为了确保砂磨过程中磨球不会逸出或者聚集在砂磨机的一端,浆料在研磨腔体中的上升速度应小于浆料液面上升速度,因此使用不同粒径的磨球都有最大限制流量。研磨过程的分散效率采用田中粉碎方程进行计算,结合实验结果可以计算出被粉碎钛酸钡颗粒的粉碎强度,结合分散效率的曲线可计算出适当的磨球粒径,实验中要达到较高的分散效率,所需的磨球粒径为0.08~0.10mm。 展开更多
关键词 砂磨机 磨球粒径 浆料流量 钛酸钡
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Magnetochronology of Mid-Miocene mammalian fauna in the Lanzhou Basin,northeastern Tibetan Plateau:Implications for Asian mammal migration
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作者 Peng Zhang hong ao +5 位作者 Andrew P.Roberts Yongxiang Li Qiang Sun Jianhui Zhang Pengfei Sun Xiaoke Qiang 《Geoscience Frontiers》 SCIE CAS CSCD 2020年第4期1337-1344,共8页
The Quantougou(QTG) Fauna in central Lanzhou Basin is an important late Mid-Miocene fauna on the northeastern Tibetan Plateau margin,but its numerical age remains a matter of debate.Here,we present a new magnetostrati... The Quantougou(QTG) Fauna in central Lanzhou Basin is an important late Mid-Miocene fauna on the northeastern Tibetan Plateau margin,but its numerical age remains a matter of debate.Here,we present a new magnetostratigraphic record for a fluvio-lacustrine section to further constrain the age of the QTG Fauna.Results suggest that the studied section spans from polarity chrons C5Cn.2n to C5 n.2n or C5 An.1n,with ages of ca.16.5 Ma to 10 Ma or 16.5 Ma to 12 Ma.The QTG Fauna is located at the top of polarity chron C5r.3 r or C5 Ar.2 r,which corresponds to an age of 11.7 Ma or 12.8 Ma for the fauna.Accordingly,the associated Myocricetodontinae(a subfamily of Gerbillidae,Rodentia) is suggested to have appeared in the Lanzhou Basin at 11.7 Ma or 12.8 Ma,which is the oldest Myocricetodontinae in East Asia but is still much younger than the ~20 Ma appearance of this subfamily in West and South Asia.Our age data support the interpretation that East Asian Myocricetodontinae originated from South Asia.The QTG fauna further suggest a dry and open grassland environment,which is consistent with global cooling after the Mid-Miocene Climatic Optimum. 展开更多
关键词 MAGNETOSTRATIGRAPHY MIOCENE Tibetan plateau Lanzhou Basin Mammal migration Myocricetodontinae
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超高效液相色谱-串联质谱检测血浆咖啡因浓度方法的建立和临床应用 被引量:3
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作者 乐娟 彭锐 +5 位作者 何琪 洪澳 吴鹏 王少亭 方成志 李艳 《中华检验医学杂志》 CAS CSCD 北大核心 2021年第8期703-708,共6页
目的建立超高效液相色谱-串联质谱(UPLC-MS/MS)方法检测血浆咖啡因浓度,评价咖啡因药物浓度监控(TDM)在早产儿呼吸窘迫综合征(RDS)治疗中的临床应用价值。方法取血浆样本于离心管中,加入咖啡因氘代同位素内标,再加入蛋白沉淀剂,充分涡... 目的建立超高效液相色谱-串联质谱(UPLC-MS/MS)方法检测血浆咖啡因浓度,评价咖啡因药物浓度监控(TDM)在早产儿呼吸窘迫综合征(RDS)治疗中的临床应用价值。方法取血浆样本于离心管中,加入咖啡因氘代同位素内标,再加入蛋白沉淀剂,充分涡旋混合后,离心取上层清液进入质谱分析。流动相为甲醇和水,梯度洗脱;柱温45℃,使用岛津LC-30AD-CL液相系统和AB SCIEX 4500 QTRAP质谱仪建立方法,并对该方法的敏感度、特异度、线性、准确度、不精密度、基质效应、携带污染进行评估。纳入2021年2至4月就诊于武汉大学人民医院新生儿科诊断为新生儿RSD的患者30例,检测不同RDS早产儿相同给药方案下的咖啡因谷值浓度以评估个体变异对咖啡因药物浓度的影响。结果咖啡因的检出限为0.02μg/ml,最低定量限为0.05μg/ml,在1.0~100.0μg/ml浓度范围内表现出良好的线性(R^(2)=0.9986,R>0.99)、特异度(回收率85.52%~114.12%)、准确度(回收率85.97%~114.53%)、日内和日间不精密度(CV 6.01%~11.28%),基质效应和携带污染可忽略不计。检测30例RSD早产儿相同给药方案(10 mg/kg)后的咖啡因谷值浓度为(25.45±11.61)μg/ml,变异系数为44.88%。结论成功建立了一种UPLC-MS/MS方法用于监测咖啡因血药浓度。咖啡因TDM具有一定的临床应用价值,可用于辅助RDS诊疗,提高咖啡因疗效。 展开更多
关键词 咖啡因 呼吸窘迫综合征 液相色谱-质谱联用 早产儿 药物浓度监控
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Identification,bioinformatic analysis and expression profiling of candidate mRNA-like non-coding RNAs in Sus scrofa 被引量:7
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作者 Bang Xiao Xingju Zhang +6 位作者 Yong Li Zhonglin Tang Shulin Yang Yulian Mu Wentao Cui hong ao Kui Li 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2009年第12期695-702,共8页
Messenger RNA-like non-coding RNAs (mlncRNAs) are a newly identified group of non-coding RNAs (ncRNAs) that may be involved in a number of critical cellular events. In this study, 93 candidate porcine mlncRNAs wer... Messenger RNA-like non-coding RNAs (mlncRNAs) are a newly identified group of non-coding RNAs (ncRNAs) that may be involved in a number of critical cellular events. In this study, 93 candidate porcine mlncRNAs were obtained by computational prediction and screening, among which 72 were mapped to the porcine genome. Further analysis of 8 representative candidates revealed that these mlncRNA candidates are not highly conserved among species. Remarkably, one of the candidates, sTF35495, was found to be precursor of a putative porcine microRNA. By RACE PCR, we determined that the full length of sTF35495 was 3 kb. The protein-coding potential of this RNA was tested in silico with no significant finding. Semi-quantitative RT-PCR analysis of the subgroup of 8 candidates revealed two distinct expression profiles and two molecules were further validated by real-time PCR. The predicted pre-microRNA sequence in this study provides a potentially interesting insight into the in vivo function of porcine mlncRNAs and our findings suggest that they play key biological roles in Sus scrofa. 展开更多
关键词 putative porcine mlncRNA chromosome localization interspecies conservation pre-microRNA RACE expression profiling qPCR
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