腔的

A bi-periodic accelerator structure with coupling cavity of arrow-shaped cross-section is described in this paper.

本文对一种使用箭型耦合腔的双周期加速结构进行了研究。

The invention is mounted at the bottom of glass vacuum heat collecting tube chamber, relative to the elastic metal support clamper.

真空集热管导热保温器安装于全玻璃真空集热管腔的底部，其器身与弹性金属支撑卡对应。

The invention discloses an optical differentiator based on a silicon-based annular cavity resonator, which belongs to the field of optical fiber communication technology.

一种基于硅基环形谐振腔的光微分器，属于光纤通信技术领域。

At first step, the processor before the deformable body contact the end face of cone die cavity regarded as an extrusion process. The minification of core boss's cross-section regarded as compressibility of direct extrusion, which acted as definition factor when construct the Direct Extrusion Model element. Another step, the model element of flat punch extrusion on wedge piece process was constructed when propose the process of deformable body overflow die corner. In this way the spherical end face of blank looked as cone end face one, t he approximate treatment is one of originality innovation in this paper. At last, the two elements have been connected and constructed the model element of cone boss part's deformation in the open die forging.

对于锥形凸台成形的第一个特征时段，即坯料和锥形凸台型腔的端面接触之前的变形过程，本文将凸台的截面缩小率转换成挤压成形的压缩率并以此为界定，建立了不同截面缩小率时的锥形模正挤压的模型单元；对于锥形凸台成形的第二特征时段即锥形模的角部充满过程，在详细考察锥形型腔端面对变形过程影响的基础上，将变形体的球形端面近似成锥面建立了平冲头挤压楔形体的模型单元；最后将前述两种模型单元有机连结，构建了开式模锻中整个锥形凸台成形过程的定量描述。

A test model of four co-rotating disks was developed as the simplified version of a typical internal cooling system of a gas turbine compressor. The investigation was on the distribution of local heat transfer coefficient and the averaged nusselt number of the downstream main disk. Experimental analysis may lead to following conclusions: the distribution is not of monotony and multi-peaks were found along the disk surface,Nu increases with the decrease of the rotational reynold number Re(subscript w,Nu increases with the axial reynold number and the grasholf number.

针对航空发动机多级压气机盘腔的冷却问题，对具有轴向通流的三腔模型进行了系统的研究，通过对局部换热特性与平均换热特性的分析，可以表征旋转盘的热应力水平和相对冷却效果，结果表明表征旋转盘热应力水平的局部换热特性在旋转盘的半径上呈多峰分布，表征相对冷却效果的平均换热特性与旋转雷诺数Re、进气雷诺数Re以及格拉晓夫数Gr有关，当Re及Gr增加时，平均努塞尔数Nu随之增加，而Re的增加使之减小。

And this causes a frequency change Δf. The resonant point tracing algorithm describes how to detect Δf. So it can introduce a feedback frequencydifference -Δf through a closed loop to realize the resonant state o In the digitaldetection scenario, using staircase wave to replace saw tooth wave, it can overcome a lot of shortcomings in the analog system. The character of the staircase wave affects the detection precision directly. This thesis analyzes a high precision scenario producing a staircase waveform in detail. It can reduce the number of the bits in D/A converter greatly. This thesis proposes another method to improve the detection precision in case that the A/D converter has comparatively little number of bits, while this method will not increase the cost of the system greatly.

在谐振式光纤陀螺中，环形谐振腔的旋转使得谐振腔的谐振频率发生了变化，从而产生了一个与旋转速度成正比的频率变化值△f，谐振点跟踪算法描述了如何检测出△f，从而可以通过闭环在系统中引入反馈频差-△f，实现光路的谐振状态；在数字闭环检测方案中，用阶梯波作为反馈信号来代替锯齿波，可以克服原来模拟系统中锯齿波的很多缺点，阶梯波的性能直接影响着系统的测量精度，本论文详细分析了一种高精度阶梯波生成方案，使得所需D／A的位数大大降低；本文还分析了A／D转换器对系统测量精度的影响，提出了一种A／D转换器位数较少的情况下提高系统测量精度的措施，同时又不会增加太多的系统成本。

Objective To study the relationship of endangium proliferation and the expression of metalloproteinases and tissue inhibitors of metalloproteinases after angioplasty of iliac artery in rabbits to investigate the probable mechanism of composite Danshen pill in prevention and treatment of restenosisMethods 30 white male rabbits of Japan （the average body weight was 25～30 kg）were randomly divided into 3 groups:normal control group,model group (intima destroyed by balloon and given hypercholesterol diet),CDP group (intima destroyed by balloon and given hypercholesterol diet plus drug CDP 150 mg/d),10 ones each groupResults The results of iliac artery angiogram and the analysis of pathology:there were lumens stenosis,thinner intima,smaller intima area,in CDP group compared with those in model group,and ratio of intima and tunica media thickness and area among each group (P＜001)Immunohistochemistry analysis:the MMP2,MMP9,TIMP1,TIMP2 in model group significantly increased than those in control group (P＜001)The CDP group had lower MMP2 and MMP9 expression,higher TIMP1 and TIMP2 expression,and increased MMP2/TIMP1,MMP9/TIMP2 than model group (P＜001)The thickening of vascular neointima and stenosis degree of vascular lumen were relevant to MMP2 and MMP9 (r=0896,P＜001)Conclusions MMP and TIMP play the very important role in the restenosis process of arteryCDP could inhibit the thickness of vascular neointima after balloon injury,the probable mechanism of which may be inhibiting collagen formation,smooth muscle immigration and decreasing hyperplasia of intima by interfering expression of MMPs and TIMPs

目的 研究兔髂动脉成形术后血管内膜增生和基质金属蛋白酶及其抑制物表达之间的关系，探讨复方丹参滴丸预防再狭窄的可能机制。方法健康成年二级雄性日本大耳白兔30只，平均体重25～30 kg。随机分为3组：正常对照组10只，模型组10只（球囊内膜剥脱加高胆固醇饮食），治疗组10只（球囊内膜剥脱加高胆固醇饮食以及复方丹参滴丸150 mg/d）。结果兔髂动脉造影、血管病理图像分析检测结果：①复方丹参滴丸组较模型组血管造影示管腔直径狭窄、内膜厚度减少、内膜面积减少、内膜厚度和中膜厚度比、面积比，各组之间有显著性差异(P＜001)。②免疫组化分析：模型组MMP2、MMP9、TIMP1、TIMP2表达均高于对照组（P＜001）；复方丹参滴丸组MMP2、MMP9的表达低于模型组，而TIMP1、TIMP2的表达高于模型组；TIMP1/MMP2、TIMP2/MMP9明显增加，差异有显著性（P＜001）。③内膜的增生以及管腔的狭窄程度与MMP2、MMP9有很好的相关性(r=0896，P＜001)。结论 MMP和TIMP在再狭窄形成中起重要作用；复方丹参滴丸能够明显抑制血管损伤后的内膜增生，可能的机制是通过影响金属蛋白酶MMP2、MMP9及其抑制物TIMP1、TIMP2的表达从而抑制胶原的生成、平滑肌的迁移、增生，而减少内膜的增生。

In order to determine further the profile of scrolls,the structural characteristics of superchargers with double-sided scrolls were analyzed and the principle of determining initial involute angle s was presented on the conditions of definite initial involute angle s,radius of base circle,and depth of scrolls.

在渐开线起始角、基圆半径和涡旋齿深度确定的条件下，为进一步确定涡旋齿的齿形，对双侧涡旋增压器的结构特征进行分析，提出始端渐开角的确定原则。通过吸气腔和排气腔的容积计算，结合回转角与渐开角的关系，给出涡旋齿始端和终端渐开角的计算方法。结果表明：该计算方法能较准确地确定涡旋盘的结构尺寸，从而可估算出整个压气机的尺寸是否满足汽车上有限的安装空间

It was shown that the SNR of the RADS could be improved by using a microwave cavity with proper microwave field mode and high microwave filling factor, a rubidium spectrum lamp with high spectrum purity and a separated isotope filtering scheme in the physics package design. The performance of the rubidium atomic frequency standard could be improved by taking all these factors into consideration.

本文分析了微波腔的结构、铷光谱灯的光谱纯度和同位素滤光方案对信噪比的影响，指出采用模式优越、微波填充因子大的微波腔，光谱纯度高的铷光谱灯，用分离滤光方法进行同位素滤光，可以提高铷原子鉴频信号的信噪比，从而使铷频标的稳定度指标得到进一步改善。

Pressure governor valve is the use of a spring-loaded power and pressure balance theory, when the spring-loaded pressure less than atmospheric pressure and the valves closed when the pressure is greater than the spring-loaded rubber tubing stretch when the bottom of compressed air diaphragm, diaphragm the effort to promote diaphragm upward and left vavle seat blow the air flow of gas, this would piston shirking role in the pressure mobile, Selection will be emissions from valve seat, air compressors made by the then air into the gas valves and exhaust emissions is through the mouth into atmospheric air compressors idling.

调压阀的原理是利用了弹簧力与压力相平衡的原理，当弹簧的压力小于气压的时候阀关闭，当压力大于弹簧的弹力时候橡胶调压膜片下方的压缩空气对膜片的用途力，推动膜片向上拱曲离开阀座而使空气流入气腔，此时卸荷活塞在气压用途下移动，将排放阀门推离阀座，于是由空气压缩机充入气腔的空气便通过排放阀和排气口排入大气空气压缩机空转。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。