熔岩管冷却过程中的热应力计算     

李镇村  石耀霖  张泽阳  董培育  杨少华 《中国科学院大学学报》2016,33(3):412-420

除本身造成的直接灾害外,火山喷发的基性熔岩流动过程中经常会形成熔岩管.由于地下空洞的存在,熔岩管附近区域的地表稳定性会降低,容易发生坍塌,造成次生灾害。月球和火星上发现的熔岩管是未来外星探测基地的最佳选择,对于熔岩管稳定性研究也具有潜在价值。本文运用有限元方法,基于熔岩管形成机制,建立熔岩管形成后温度演化过程和相应的位移和热应力状况.通过分析熔岩管附近主应力的演化过程,考察不同物理参数(熔岩管的大小、深度、形状)对于熔岩管稳定性的影响。  相似文献   

镜泊湖地区旅游地质研究     

康春国 《哈尔滨学院学报》2005,26(2):101-103

文章对镜泊湖地区的地质旅游进行了相关的论述，在此基础上对镜泊湖的地质成因、熔岩隧道、以及地下森林的形成过程作了进一步的研究，尤其对镜泊湖的火山活动时代进行了讨论。  相似文献   

History of the preanalytical phase: a personal view     

Walter G. Guder 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2014,24(1):25-30

In the 70ies of the last century, ther term “preanalytical phase” was introduced in the literature. This term describes all actions and aspects of the “brain to brain circle” of the medical laboratory diagnostic procedure happening before the analytical phase. The author describes his personal experiences in the early seventies and the following history of increasing awareness of this phase as the main cause of “laboratory errors”. This includes the definitions of influence and interference factors as well as the first publications in book, internet, CD-Rom and recent App form over the past 40 years. In addition, a short summary of previous developments as prerequesits of laboratory diagnostic actions is described from the middle age matula for urine collection to the blood collection tubes, anticoagulants and centrifuges. The short review gives a personal view on the possible causes of missing awareness of preanalytical causes of error and future aspects of new techniques in regulation of requests to introduction of quality assurance programs for preanalytical factors.  相似文献   

槽形抛物镜太阳能集热器的气象分区研究     

乔力  葛新石  余光宝 《中国科学院研究生院学报》1997,(1)

依据热阻网络法所建立的槽形抛物镜——管簇结构腔体式吸收器太阳能集热器的稳态分析模型,和文中建立的集热器气象分区模型,在已知各种气象资料的前提下对世界上有代表性的各地区进行了一年各月热性能对比的气象分区研究。  相似文献   

1.Research Institute of Petr     

《高等教育研究》2006,(2)

  相似文献   

深井冻结凿井冻结管断裂原因分析及防治技术     

亢延民 《淮南职业技术学院学报》2006,6(3):1-4

在冻结法凿井中,因局部冻结管断裂,造成盐水泄漏,会引起连锁断管反应,降低冻结壁强度,威胁冻结凿井安全,如何防止冻结管断裂或在局部断管后如何采取有效的补救措施避免事故的进一步扩大,是冻结法凿井施工中的技术难题;在冻结管断裂原因、防止冻结管断裂和处理冻结管断裂技术等方面进行了具体分析,供类似深井冻结法施工参考。  相似文献   

Application of Non-homogeneous Solution for Equations of Slender Ring Shells to Overall-Bending Problem of Ω-Shaped Bellows   总被引：2，自引：0，他引：2  

Zhu Weiping Guo Ping 《上海大学学报(英文版)》1999,(2)

ＮｏｍｅｎｃｌａｔｕｒｅｂｒａｄｉｕｓｏｆｔｈｅｒｉｎｇｓｅｃｔｉｏｎｈｔｈｉｃｋｎｅｓｏｆｒｉｎｇｓｈｅｌｓＲｒａｄｉｕｓｏｆｔｈｅｐａｒａｌｅｌｃｉｒｃｌｅＲ１,Ｒ２ｒａｄｉｏｆｔｈｅｐｒｉｎｃｉｐａｌｃｕｒｖａｔｕｒｅ,Ｒ２＝ｂＲｍａｖｅｒａｇ...  相似文献   

钼锑抗分光光度法测定地表水中总磷的若干影响因素   总被引：1，自引：0，他引：1  

卢胜才 《嘉应学院学报》2003,21(6):30-32

研究了具塞比色管、浊度等对用钼锑抗分光光度法进行地表水中总磷的测定的影响,说明在测定时,需要进行比色管的预处理,同时综合考虑浊度等的影响。  相似文献   

无油真空系统在荧光显示管生产中的作用     

张立新 《湖南师范大学教育科学学报》1998,(2)

本文主要研究用无油真空系统作为排气方法在荧光显示管生产中的作用．  相似文献   

Preanalytical quality improvement – in quality we trust     

《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2013,23(1):A1-A55

Background

The preanalytical phase represents the major source of variability in laboratory diagnostics. Our aim was to assess to what extent underfilling of primary blood tubes may impact upon routine coagulation testing.

Materials and methods:

Blood was drawn by syringe from 21 healthy volunteers and 6 patients on warfarin therapy, and immediately transferred into 3.6 mL vacuum tubes containing 3.2% sodium citrate (Terumo Europe N.V., Leuven, Belgium). All tubes were filled using standardized volumes of whole blood to produce scalar amounts of filling: 3.6 mL (i.e., 100%), 3.2 mL (89%), 2.8 mL (78%) and 2.4 mL (67%). Samples were mixed and centrifuged at 1300 × g for 10 min. The plasma was tested for prothrombin time (PT), activated partial thromboplastin time (APTT) and fibrinogen (FBG) on ACL TOP (Instrumentation Laboratory - IL, Milan, Italy), using IL reagents. A polynomial plot was derived for each parameter from interpolation of clotting values obtained with different percentages of filling, and these plots were compared with quality specifications (± 2.0 for PT, ± 2.3 for APTT and ± 4.8 for FBG) to calculate the minimal filling volume required to produce clinically acceptable results.

Results:

The equations were (PF, Percentage of filling): PT (sec) = 3.375 × PF^2–6.255 × PF + 17.806 (r = 0.980); APTT (sec) = 8.925 × PF^2–23.578 × PF + 46.356 (r = 0.979); and FBG (mg/dL) = −311.5 × PF^2 + 422.1 × PF + 147.07 (r = 0.994). According to these equations, the minimum allowed thresholds of blood tubes filling were > 61% for PT, > 87% for APTT and > 71% for FBG.

Conclusions:

Our results confirm that routine coagulation testing performed on underfilled tubes may generate biased and clinically misleading test results. This is particularly critical for APTT, wherein tubes filled at less than ∼90% generate unreliable data. The FBG and the PT seem more resistant to underfilling, clinical significant biases being observed only where blood tubes were filled at less than ∼60 and ∼70%, respectively.  相似文献