目的探讨临床实验室单标本气动传输系统改进对血清神经元特异性烯醇化酶(neuron-specific enolase,NSE)和细胞角蛋白19片段抗原21-1(cytokeratin 19 fragment antigen21-1,Cyfra21-1)检测结果的影响及效果评价。方法2021年随机化抽样取6...目的探讨临床实验室单标本气动传输系统改进对血清神经元特异性烯醇化酶(neuron-specific enolase,NSE)和细胞角蛋白19片段抗原21-1(cytokeratin 19 fragment antigen21-1,Cyfra21-1)检测结果的影响及效果评价。方法2021年随机化抽样取60例员工并采集两管血液标本分为气动传输组(A)和人工转运组(B),以B组为对照组。A组通过单标本气动传输系统,B组通过人工转运同时进行NSE和Cyfra21-1检测。2022年随机化抽样取60例员工,前30例员工用干燥管采集两管血液标本分为改进后干燥管气动传输组(C)、改进后干燥管人工转运组(D)。前31~60例员工用分离胶管采集两管血液标本分为改进后分离胶管气动传输组(E)、改进后分离胶管人工转运组(F)。离心后C组和E组通过单标本气动传输系统,D组和F组通过人工转运,四组标本同时进行NSE和Cyfra21-1检测,以D组和F组为对照组。使用配对t检验比较六组NSE和Cyfra21-1检测结果之间差异并评价存在差异的结果偏倚是否为临床所允许。结果A组与B组的NSE(20.79±6.97ng/ml,14.31±4.10ng/ml),Cyfra21-1(1.630±0.777ng/ml,1.793±0.786ng/ml)之间结果差异有统计学意义(t=5.672,-5.698,均P<0.05),C组(15.04±3.60 ng/ml,12.85±1.71ng/ml)和D组(1.703±0.156ng/ml,1.797±0.161ng/ml)之间结果差异有统计学意义(t=4.529,-4.260,均P<0.05)。E组和F组的NSE(12.94±1.62ng/ml,12.88±1.57ng/ml)结果差异无统计学意义(t=0.308,P>0.05),Cyfra21-1(1.660±0.154ng/ml,1.771±0.159ng/ml)差异有统计学意义(t=-5.169,P<0.05)。NSE使用干燥管偏倚大于可接受范围,而Cyfra21-1使用干燥管和分离胶管偏倚均可接受。结论标本使用分离胶管离心后进行气动传输系统转运对NSE结果无影响。干燥管和分离胶管进行气动传输系统转运对Cyfra21-1有一定影响但可以接受。气动传输系统改进后可以减少对NSE结果的影响。展开更多
TN929.11 98010444高速大容量密集波分复用光纤传输实验系统=Highspeed and high eapascity HD-WDM opticalfiber communication testbed[刊,中]/谢世钟,刘凤海,孙成城(清华大学.北京(100084))//激光与红外.-1997,27(1).-42-47介绍863...TN929.11 98010444高速大容量密集波分复用光纤传输实验系统=Highspeed and high eapascity HD-WDM opticalfiber communication testbed[刊,中]/谢世钟,刘凤海,孙成城(清华大学.北京(100084))//激光与红外.-1997,27(1).-42-47介绍863计划光电子主题建立的光电子器件试验床的概况及最近的实验结果。图8参5(李瑞琴)展开更多
There are three well known types of wire lines for transmitting electrical energy or information. The first type is ordinary two wires line （below A-Line）. The second type is so-called single-wire line, where ground...There are three well known types of wire lines for transmitting electrical energy or information. The first type is ordinary two wires line （below A-Line）. The second type is so-called single-wire line, where ground plays the role instead of second wire. Polyphase systems belong to the third type, three phase system is the most popular among them. The purpose of this article is another attempt to build a one-wired （without ground） system--the transmission of electrical energy. In this paper an original idea of building such a system is justified, the results of simulations and laboratory modeling are presented. It is shown that the proposed method can reduce the cost of electric transmission lines, the losses in them and significantly reduce interferences.展开更多
Many monographs point out that differential encoding and decoding is necessary for ef- fectual information transmission against phase ambiguity while seldom discuss the reason why phase ambiguity will emerge inevitabl...Many monographs point out that differential encoding and decoding is necessary for ef- fectual information transmission against phase ambiguity while seldom discuss the reason why phase ambiguity will emerge inevitably.Available algorithms are specially designed for certain modulation scheme;these algorithms cannot satisfy the requirement of soft-defined radio,which perhaps demands a uniform algorithm for different modulations.This paper proposes a new opinion on phase ambiguity from the view of probability.This opinion believes that modulating symbol sequence can affect,at optimum sampling epoch,the modulated waveform as oscillating carrier has done,and so the stochastic sequence leads to phase ambiguity.Based on a general signal model,this paper also puts forward a novel universal algorithm,which is suitable for different signals,even some new ones,by configuring several parameters.展开更多
In this paper several kinds of high temperature molten salts were investigated experimentally on viscosity-temperature characteristics with high-temperature viscometer.The viscosities of the molten salts were measured...In this paper several kinds of high temperature molten salts were investigated experimentally on viscosity-temperature characteristics with high-temperature viscometer.The viscosities of the molten salts were measured and compared with those from references to verify the reliability of the viscometer and measuring methods,and a good agreement was observed from the comparisons.Then,two new high-temperature molten salts were made from the HITEC salt by some additives and the viscosity-temperature profiles of them were obtained by experiments.The results show that the new molten salts have much lower viscosities,thus suitable for reducing the flow resistance in transportation system of high-temperature solar thermal power generation.展开更多
文摘TN929.11 98010444高速大容量密集波分复用光纤传输实验系统=Highspeed and high eapascity HD-WDM opticalfiber communication testbed[刊,中]/谢世钟,刘凤海,孙成城(清华大学.北京(100084))//激光与红外.-1997,27(1).-42-47介绍863计划光电子主题建立的光电子器件试验床的概况及最近的实验结果。图8参5(李瑞琴)
文摘There are three well known types of wire lines for transmitting electrical energy or information. The first type is ordinary two wires line （below A-Line）. The second type is so-called single-wire line, where ground plays the role instead of second wire. Polyphase systems belong to the third type, three phase system is the most popular among them. The purpose of this article is another attempt to build a one-wired （without ground） system--the transmission of electrical energy. In this paper an original idea of building such a system is justified, the results of simulations and laboratory modeling are presented. It is shown that the proposed method can reduce the cost of electric transmission lines, the losses in them and significantly reduce interferences.
基金Supported by Henan Prominent Talents Innovation Foundation (No.0421000100).
文摘Many monographs point out that differential encoding and decoding is necessary for ef- fectual information transmission against phase ambiguity while seldom discuss the reason why phase ambiguity will emerge inevitably.Available algorithms are specially designed for certain modulation scheme;these algorithms cannot satisfy the requirement of soft-defined radio,which perhaps demands a uniform algorithm for different modulations.This paper proposes a new opinion on phase ambiguity from the view of probability.This opinion believes that modulating symbol sequence can affect,at optimum sampling epoch,the modulated waveform as oscillating carrier has done,and so the stochastic sequence leads to phase ambiguity.Based on a general signal model,this paper also puts forward a novel universal algorithm,which is suitable for different signals,even some new ones,by configuring several parameters.
基金supported by the National Natural Science Foundation Key Project of China (Grant No. 50736005)the National Basic Research Program of China ("973" Program) (Grant No. 2010CB227103)
文摘In this paper several kinds of high temperature molten salts were investigated experimentally on viscosity-temperature characteristics with high-temperature viscometer.The viscosities of the molten salts were measured and compared with those from references to verify the reliability of the viscometer and measuring methods,and a good agreement was observed from the comparisons.Then,two new high-temperature molten salts were made from the HITEC salt by some additives and the viscosity-temperature profiles of them were obtained by experiments.The results show that the new molten salts have much lower viscosities,thus suitable for reducing the flow resistance in transportation system of high-temperature solar thermal power generation.
