AGB星的超星风与热脉动的研究

至今国际上对ＡＧＢ星的超星风、热脉动及振动的理论研究工作中都忽略了湍流压的存在，然而对于一个整个外壳都处于完全对流的ＡＧＢ星，湍流压是存在的，并且由于湍流压的存在将对气体压强、密度、温度以及各热力学量产生影响，因而对ＡＧＢ星的超星风、热脉动及振动产生影响。本文以恒星结构演化理论中常用的混合程对流理论为基础，给出了湍流压以及考虑湍流压情况下恒星内部物态方程和各热力学量的表达式，并给出了判别恒星外壳产生动力学非稳定性的判据，并在此基础上研究了质量为２．８Ｍ⊙和７Ｍ⊙的恒星从主序到ＡＧＢ星的演化。目的是研究有湍流压情况下ＡＧＢ星的超星风及热脉动的机理。结果表明，对于７Ｍ⊙恒星，在红巨星及ＡＧＢ阶段，湍流压可以达到总压强的３０％，并且对恒星的结构产生重要影响，对于２．８Ｍ⊙恒星，在红巨星及ＡＧＢ阶段影响较小。由于湍流压的作用，２．８Ｍ⊙和７Ｍ⊙恒星在ＡＧＢ阶段和红巨星阶段，靠近表面的区域会出现动力学非稳定性，造成物质向外喷流，这就是ＡＧＢ星和红巨星产生强大星风的物质损失的原因。研究还表明，湍流压效应造成７Ｍ⊙ＡＧＢ星的氢燃烧壳层产生主周期为５０年的脉动现象。

热脉动联合光润强脉冲光治疗睑板腺功能障碍性干眼症的效果

目的:探讨热脉动联合光润强脉冲光(Intense pulsed light,IPL)治疗睑板腺功能障碍性干眼症的效果。方法:选取2019年7月-2020年9月东莞爱尔眼科医院收治的106例(212眼)睑板腺功能障碍性干眼症患者作为研究对象,进行前瞻性随机对照研究,根据Doll’s临床病例随机表分为研究组(36例,72眼)、对照A组(35例,70眼)、对照B组(35例,70眼)。对照A组采用热脉动治疗,对照B组采用光润IPL治疗,研究组采用热脉动联合光润IPL治疗。比较三组患者疗效、治疗前后干眼评估问卷(Standard patient evaluaion of eye dryness,sPEED)评分、泪膜破裂时间(Tearbrenkuptime,TBUT)、基础泪液分泌实验(Schirmer I test,SIt)、脂质层厚度(Lipidlayerthickness,LLT)、不完全眨眼频率(Partial blink rate,PB)和随访6个月后的复发率。结果:研究组治疗总有效率高于对照A组、对照B组,差异有统计学意义(χ^(2)=7.241,P<0.05);随治疗的进行三组患者sPEED评分呈降低趋势,研究组低于对照A组、对照B组,差异有统计学意义(F=41.357、19.641、48.366,P<0.05);随治疗的进行,三组患者TBUT、SIt、LLT呈增加趋势,研究组大于对照A组、对照B组,差异有统计学意义(F=28.631、19.671、21.444;F=19.144、13.114、13.156;F=30.593、21.579、24.360,P<0.05);随治疗的进行,三组PB呈降低趋势,研究组小于对照A组、对照B组,差异有统计学意义(F=21.341、11.436、23.876,P<0.05);随访6个月,研究组脱落3例,对照A组、对照B组各脱落2例,研究组复发率低于对照A组、对照B组,差异有统计学意义(χ^(2)=11.696,P=0.003)。结论:热脉动联合光润IPL治疗睑板腺功能障碍性干眼症疗效显著,可有效改善患者干眼症状,降低PB,增加SIt、LLT,维持泪膜稳定,复发率低,治疗效果更稳定。

场协同理论及其在脉动流传热技术中的应用前景

针对目前脉动流强化传热研究中的问题,提出了将场协同理论应用于其机理研究。分析了现有脉动流强化传热问题的研究理论,指出了现有理论的局限性。介绍了场协同理论,阐述了其在研究脉动流强化传热问题中的优势。结合已有研究结果,分析了场协同的观点应用于脉动流强化传热研究的可行性和应用前景。研究结果表明,场协同理论是独立于具体技术之外的基本理论,将其应用于脉动流强化传热机理研究是必要的和可行的,得到的结论具有较好的普遍性,对于脉动流强化传热技术的工程应用与理论研究具有指导意义。

PIV技术在脉动流传热实验中的应用

为了将PIV技术应用于脉动流传热研究,结合Dantec公司的PIV测量系统,搭建了脉动流传热实验台,探讨了在脉动流传热实验测量过程中,示踪粒子的选择和系统标定等问题,提出了脉动流场PIV测量示踪粒子选取及密闭流道标定的方法,利用Dynamic Studio软件中的自适应互相关算法得到了清晰的涡量图和流线图,验证了方法的正确性及PIV技术应用于脉动流传热实验的可行性.

热液脉动与岩浆涌动控制机理浅论

热液脉动与岩浆涌动的控制机理，是基础地质理论所涉及的两个重要议题。本文首先对当今流行的构造控制机理提出了质疑，其后借助＂间歇喷泉＂原理和＂吹气球＂机制，分别对热浪的脉动和岩浆的涌动进行了必要的探讨。

15w大卡热声耦合脉动燃烧加热炉的研制

针对传统加热炉存在钢材耗量高、体积大、燃烧效率低等缺点,研制出以热声耦合脉动燃烧器为核心的15w大卡油田用加热炉,形成了在声学条件控制下的周期性脉动燃烧,极大强化了混合、传热和传质过程,从而达到提高热效率,节省燃料的目的。

单相电容运转式电动机空载过热的原因分析

本文阐述了单相电容运转式电动机旋转磁场产生的基本条件,分析了空载过热的主要原因,提出了正确使用和维护的一般方法。

2.8M_⊙碳AGB星的形成和演化

在混合程对流理论基础上建立了考虑了湍流压的恒星结构与演化理论，以及在对流外壳中出现动力学非稳定性的判据。在此基础上研究了初始质量为2．8M⊙的星族I恒星从主序星到碳AGB星的质量非守恒演化。结果表明，在RGB星和AGB星阶段，靠近恒星表面区域内湍流压可以达到总压强的30％。且湍流压效应可能是导致RGB星和AGB星靠近表面区域产生了动力学非稳定性，从而造成物质向外逃逸的原因。我们认为湍流压效应可能就是造成有效温度低因而辐射压也低的RGB星产生强星风，以及AGB星产生超星风的物理原因。还发现当氦燃烧层源厚度与层源质量的比值小于0．04R⊙／M⊙时，层源内会出现热核反应的非稳定现象，即出现热脉动，且2．8M⊙AGB星经过6次热脉动后，恒星表面的C／O超过1，恒星演化成碳AGB星。

Adriamycin Thermotherapy through the Hepatic Artery Using VX2 Carcinoma in Rabbit Liver as a Model

OBJECTIVE It has been reported that heating can enhance sensitivity of rabbit VX2 cells to adriamycin and increase the intracellular concentration of adriamycin. This study was designed to evaluate the anti-tumor effect of interventional hyperthermia and interventional thermochemotherapy on VX2 carcinoma in rabbit liver. METHODS VX2 carcinoma cells were surgically implanted into the right liver lobe of 60 male New Zealand white rabbits, which were randomly divided into 4 groups (15 per group). The 4 groups (designated as 1, 2, 3, 4 respectively) were injected with 10 ml of the following via the hepatic artery: physiological saline (37℃); adriamycin (37℃); physiological saline (60℃); adriamycin (60℃). One week later, the tumor volume, serum level of aspartate transaminase (AST) and the survival of the rabbits bearing VX2 were observed and compared among the different treated groups. RESULTS The tumor growth rate in group 4 (ADM 60℃) (0.53±0.21)% was significantly lower than that in group 1 (3.48±1.17)%, in group 2 (1.09±0.26)% and group 3 (3.32±1.28)% (P<0.05, P<0.05, P<0.01, respectively). The days of survival days for group 4 (87.0±2.0) were significantly more than that in group 1 (40.0±3.0). Group 4 showed a significantly higher increase in serum AST compared to group 1 (P<0.05), but without significant differences compared to the other groups (P>0.05). CONCLUSION Adriamycin treatment at 60℃ significantly deceased the tumor growth, prolonged the survival period and resulted in reversible liver damage.

Parametric Influence on Thermal Performance of Flat Plate Closed Loop Pulsating Heat Pipes

This paper presents an experimental study on a flat plate closed loop pulsating heat pipes. It consisted of total 40 channels with square cross section （2 × 2 mm^2, 165 mm long） machined directly on an aluminum plate（180×120×3 nm^2）, which was covered by a transparent plate. The working fluid employed was ethanol. As the results, the influence parameters of thermal performance were investigated, such as filling ratio, heat load and operational orientations etc. Filling ratio was found to be a critical parameter, and its effect was rather complicated. According to its values the PHP plate could have four distinct working zones with different operational characteristics and heat transfer performance. The effect of heat load on thermal performance was found to be positive, and in general, iucrcasing the heat load would improve heat transfer performance. In order to analyze the effect of gravity on thermal performance, three different heat modes and total seven tilt angles were tested and compared. Successful operation at all orientations with respect to gravity was also achieved.

Heat Transfer Properties and Chaotic Analysis of Parallel Type Pulsating Heat Pipe

The refrigerant mixture of ethanol aqueous was applied to the parallel type pulsating heat pipe (PHP). The operation characteristics of the PHP were analyzed by means of experiment and nonlinear chaotic theory. Moreover, the relationship between the running state and attractor was described. The results indicate that starting power, stable running power and dry burning transition power are about 64.08 W, 148.68 W and 234.0 W respectively. The cycle and amplitude of PHP initially decrease and then increase with the increasing power. However, the data are welldistributed in a certain range. The running state is in agreement with the attractors, and the changing process for attractors is as follows: the attractors first disperse in the whole phase space, then present mass status, and finally show band distribution.

Computer Controlled High Precise, High Voltage Pules Generator

High precise, high voltage pulse generator made up of high-power IGBT and pulse transformers controlled by a computer are described. A simple main circuit topology employed in this pulse generator can reduce the cost meanwhile it still meets special requirements for pulsed electric fields (PEFs) in food process. The pulse generator utilizes a complex programmable logic device (CPLD) to generate trigger signals. Pulse-frequency, pulse-width and pulse-number are controlled via RS232 bus by a computer. The high voltage pulse generator well suits to the application for fluid food non-thermal effect in pulsed electric fields, for it can increase and decrease by the step length 1.

Performances of Flat Plate Pulsating Heat Pipes

Flat plate pulsating heat pipe is useful for hot spot heat spreader. Two kinds of flat plate spreader of pulsating heat pipe are designed, fabricated and experimented. For the embedded circular capillary type, the transferred heat flux could reach 32 W/cm2, the smallest thermal resistance for acetone, methanol and FC-72 were respectively 0.50, 0.57 and 0.40℃/W. While for the square capillary type, the transferred heat flux could reach 26 W/cm2, the equivalent thermal conductivity could reach 3211 W/（m. ℃）. There are ranges of optimal transferred power and filling ratio for different working liquid. If the transferred power is constant, changing the heating area and the place has little effects on the performance.

Clopidogrel induced arthritis and fever

A 67-year-old woman with a history of diabetes mellitus and smoking was admitted to our hospital with chest pain for one month. Her resting electrocardiogram and serial troponin I measurements were normal. As the coronary artery angiography performed in another hospital showed severe lesions in the left anterior descending artery, we planned to perform the intervention on the left anterior descending artery by stent. Before the procedure, clopidogrel （300 mg loading dose） was initiated.

The Role of Heat Shock Protein 70, IgE and MMP-9 in Detecting Early Minor Myocardial Damage and Evaluating the Efficacy of Coronary Artery Bypass Grafting （CABG）

The objective of this research was to identify levels of heat shock protein 70 （Hsp 70）, total immunoglobulin E （IgE） and matrix metalloproteinase-9 （MMP-9） before and after coronary artery bypass grafting （CABG） surgery. Hsp 70, IgE, MMP-9, creatine phosphokinase-MB （CPK-MB）, and lactate dehydrogenase （LDH） levels were measured in normal subjects （n = 20）, and in patients with chronic stable angina pectoris who were referred for elective CABG, before and after performing CABG-surgery （n = 20）. Compared with normal subjects, increased Hsp 70 and IgE levels, unchanged MMP-9 level, and activities of CPK-MB and LDH were found in the pre-operative patient group. Hsp 70 and IgE levels in the post-operative period were significantly reduced when compared to pre-operative period. Hsp 70 and IgE might be used as markers for detection of early minor myocardial damage, and coronary insufficiency with less overt damage than myocardial infarction, as significant changes in their levels appear before occurrence of in any changes in the levels of MMP-9, CPK-MB and LDH. Besides, Hsp 70, and IgE returning to the normal levels after CABG surgery, suggest that they could be helpful to evaluate the effect of CABG surgery.

热声耦合燃烧振荡中火焰锋面识别分析

针对火焰图像中火焰锋面位置难以确定的问题,通过自行开发MATLAB程序和恒定强度阈值算法对图像中的火焰锋面边界进行识别和优化,对图像的二值图进行形态学处理,获得时域内火焰锋面的归一化面积曲线;利用Labview程序实现高速照相机、光电倍增管和麦克风的同步触发,结合频谱信息得到相同周期内的归一化面积脉动和热释放率脉动。分析后显示,两者变化趋势基本相同,皮尔逊相关系数为0.915,为极强相关关系,验证了此方法的可行性。

Effects of Pulsation on Separated Flow and Heat Transfer in Enlarged Channel

Numerical results of three-dimensional separated flow and heat transfer in an enlarged rectangular channel are presented in this paper.The expansion ratio and aspect ratio of the channel are 2.0 and 16.0,respectively.Reynolds number of the flow is 200 and it is over the critical Reynolds number.Over the critical Reynolds number,the flow in the symmetric channel becomes asymmetric and deflects to one side of the walls.Effects of the pulsating fluctuation at the inlet upon the flow in the channel are investigated.It is clarified that the inlet flow with a pulsating fluctuation of Strouhal number 0.05 and 0.10 strongly affects on the flow in the channel,and heat transfer on the walls is enhanced,especially on the wall surface covered with long separation bubble.On the other hand,the pulsation of St=0.0125 oscillates the shear layer more weakly than that of St=0.05,0.10 and the enhancement of heat transfer is smaller,though some vortices are shed from the vicinity of the side wall near the reattachment region.The oscillation of the main flow calms down gradually as the Strouhal number of the pulsation increases over 0.10.The influence of pulsation of St=0.20 on the flow is restricted in the near downstream of the step,and heat transfer on the walls is almost similar to that of the steady flow in the channel.

Experimental Study of Flow Patterns and Improved Configurations for Pulsating Heat Pipes

A series of experiments were performed on three types of closed loop pulsating heat pipes （PHPs）, intending to investigate various kinds of flow patterns, and to develop some improved configurations for the PHPs. Optical visualization results indicated that there might exist three flow patterns, i.e. bubble-liquid slug flow, semi-annular flow and annular flow, corresponding to different working conditions. For a given geometry and an adequate fill ratio, the PHPs had the self-adjusting characteristic for the flow patterns （from slug flow to semi-annular and then to annular flow） to meet the demands of the increasing heat input. Two special configurations, one with alternately varying channel diameter, the other equipped with one section of thicker tube, were found to be advantageous in establishing and maintaining reliable circulation of the working fluid. The thermal performance of the PHPs was examined over a range of working conditions. Comparing with the normal PHP with uniform diameter, either of the improved PHPs exhibited higher thermal performance.

An Experimental Investigation on Heat Transfer Performance of Nanofluid Pulsating Heat Pipe

The effect of SiO2 particles on heat transfer performance of a pulsating heat pipe （PHP） was investigated experi- mentally. DI water was used as the base fluid and contrast medium for the PHP. In order to study and measure the character, there are SiO2/H20 nanofluids with different concentration and applying with various heating powers during the experiment investigation. According to the experimental result, the high fraction of SiO2/H20 will de- teriorate the performance of PHP compared with DI water, i.e. the thermal resistance and the temperature of evaporation section increases. It is in contrary in the case of low fraction of SiO2/H20. Finally, the comparison of the thermal performances between the normal operation system and the static settlement system is given. It is found that both the thermal resistance of nanofluid PHP and the temperature of the evaporation section increase after standing for a period, and it is the same trend for the temperature fluctuation at the identical heating power for PHP.

Experimental Study on the Start Up Performance of Flat Plate Pulsating Heat Pipe

An experimental system of flat plate pulsating heat pipe was established and experimental research was carried out in this system to know the mechanism of heat transfer, start-up and operating characteristics. The factors, such as filling rate, heating power, heating method etc, which have great influence on the thermal performance of the plate pulsating heat pipe were discussed. The results indicate that heating power and filling rate are the important factors for the start-up of the plate pulsating heat pipe. The different start-up power is needed with different filling rate, and the start-up of the heat pipe in case of bottom heated is much easier than that of top heated. Increasing the heating power and enlarging the heating area can make the start-up easier. Heating power can also affect the start-up time of heat pipe under the condition of bottom heated, while it does not have some influence to the heat pipe of top heated. The thermal resistance of plate pulsating heat pipe is related with the heating power, and the higher the heating power is, the smaller the thermal resistance is. But the best filling rate which the heat pipe needs is different with different heating methods, and the performance of the heat pipe in the case of bottom heated is better than the others.