压下的

In addition, some experience formulas for them are regressed. The third chapter establishes a unified S-N curve equation to calculate multi-axial fatigue ultimate strength of concrete considering both the effect of confinement and minimum/maximum stress ratio, based on the triaxial fatigue test data in this paper and the test results under uniaxial and biaxial fatigue loading in previous literatures. Moreover, the consistency of calculating condition fatigue ultimate strength with fatigue life distribution and initial ultimate strength distribution is analyzed.

第二章简要地介绍了本文三轴疲劳试验装置，进行了两向等侧压约束下混凝土立方体试件三轴受压等幅和变幅疲劳试验，分析了三轴受压疲劳破坏机理，给出了相应的疲劳破坏试验判断标准；得到了混凝土在两向侧压约束下单级和多级受压疲劳的变形发展规律，包括最大纵向应变、残余应变、最大纵向应变率和疲劳变形模量等随循环次数的发展规律以及疲劳损伤的演变规律，并给出了相应的经验公式。

Comparison between the velocity distributions at the different flow rate conditions showed that increasing the flow rate was help to improving the velocity distribution. The periodic mean field on r-6 plane at different axis positions showed that the flow within the vaned diffuser, especially within the inlet region, was periodic unsteady when impeller located at the different circumferential position, just as the flow within the vaneless diffuser.

有叶扩压器内平均流场的分析表明，在定常流动的假设下，不同流量工况下有叶扩压器的内部流动也呈现为沿轴线向后盘方向推移流动状况逐渐恶劣的分布规律，表明二元叶片构成的平行直壁有叶扩压器对轴向不均匀流动的掺混作用仍然不大。

SRF was drainaged by a technique whereby a radial scleral penetrating of 1~2mm deep was made with a sharp knife in 45 oblique angle.Thus,the outflow of SRF can be controlled.The SRF was discharged as the inferior valve of the sclerotomy was been pressing and the drainage was stopped as the pressing was relieved.

在一组连续78例（79眼）简单裂孔性视网膜脱离外路显微手术中，用11号尖刀片，在要排液的部位以45°角倾斜、放射状刺入巩膜约1～2mm，形成一种用刀片压住巩膜切口下唇，视网膜下液即流出，不压下唇即封闭的巩膜切口。

Hydraulic screw down system of cold rolling sheet plant of Benxi Iron and Steel Company was studied,physical and mathematical models of every part of hydraulic screw down were established and transfer function of the whole system under position control was deduced.

通过对本钢冷轧厂四辊冷带轧机液压压下系统的研究，对液压压下系统的各个环节建立了物理和数学模型，推导出了整个系统在位置控制方式下的传递函数。

In order to determine the saturated vapor pressure of colloid ed dinitrogen tetroxide,and find out its change rule with the various temperature,a testing equipment of determining satuated vapor pressure of colloid ed dinitrogen tetroxide was designed and constructed according to the principle of static testing.

为了测定胶体四氧化二氮的饱和蒸气压，找出其在不同温度条件下的变化规律，采用静态法测试原理，自行设计建立了四氧化二氮胶体饱和蒸气压的测试装置，测得了常压下液体和胶体四氧化二氮的饱和蒸气压数据，结果表明，四氧化二氮体系成胶后比成胶前的饱和蒸气压略有降低，且温度越高其差值越大。

In this thesis, the influence of column force, joint hoop reinforcement, and repeat load on the stress and sheer bearing capability of inclined pressure bar is analyzed utilizing finite element software. In the case study, the column axial force's influence on the inclined pressure bar's equivalent width, stress and sheer bearing capability of RCFEN is obtained by changing the column force when modeling the RCFEN with ANSYS. In the former model, the joint hoop reinforcement influence on the equivalent width inclined pressure bar and the strength of RCFEN is achieved by changing the quantity of joint hoop reinforcement; the inclined pressure bar's equivalent width and the strength variation of RCFEN under cyclic load are gained by applying low frequency cyclic load on the inflection point of column and the middle of beam.

针对上述算例中的框架外节点采用ANSYS进行建模，运用有限元软件分析了柱轴力、节点箍筋、反复荷载对外节点斜压杆承载力、抗剪承载力的影响：改变柱轴力，研究了柱轴力对斜压杆的等效宽度、框架外节点斜压杆承载力、框架外节点斜压杆抗剪承载力的影响；在上述模型中，改变节点箍筋的数量，分析了节点箍筋对斜压杆的等效宽度、框架外节点强度的影响；在上述模型中，在柱反弯点和梁中点均进行低周反复加载，讨论了在反复荷载作用下，框架外节点的斜压杆的等效宽度、框架外节点强度的变化情况。

A simplified mechanical model of a typical axially loaded sleeved compression member is introduced. Some reasonable constitutive relation curves of the inner steel tube are chosen for analyzing in two numerical examples. One is analysis on its axially loaded bearing capacity under different working conditions. The other is stability analysis of grid structure with SCM. The buckling control effect of the inner steel tube is evaluated with the outer steel tube applied in these conditions.

阐述了轴心受压情况下典型套管构件的简化力学模型，选择利用合理的套管构件内核本构关系，用2个算例（内核圆钢管不同工况下的轴压承载力分析和网架结构应用套管构件的稳定计算分析）分析了外钢管对轴心受压内钢管的失稳控制效果。

Second, considering the influence of well resistance, smear effect and structure breakage of thick soft clay, the equivalent calculation method is proposed. That is, the partially penetrating sand drain ground is viewed as the double-layered ground, and its consolidation is analyzed with 1-D consolidation theory, through the transformation from 3-D consolidation to 1-D consolidation in the region of sand drain. This can overcome the disadvantage that the excess pore water is discontinuous between the region of sand drain and under-lying soft layer. To the double-layered ground, based on the consolidation mechanism under surcharge, the excess pore water pressure calculation formula is deduced under the condition of multilevel equably loading or unloading, which perfects the consolidation theory.

然后，在充分考虑竖井区井阻、涂抹作用以及土体结构损伤破坏对固结影响的基础上，将未打穿竖井地基合理地转化为双层地基，按一维固结理论计算，克服了传统固结计算方法在竖井处理区与下卧层交界面处存在孔压间断的缺点；在此基础上，从超载预压法的基本原理出发，分析了双层地基超载预压固结、沉降机理，推导了多级等速加、卸载情况下双层地基的固结计算公式，进一步完善了双层地基固结理论。

During the fracturing for low pressure and low permeability gas reservoirs, there are some main problems in conventional hydroxypropylguar - organic boron cross-linking system: Firstly, the water-lock damage to low pressure and low permeability gas formations by filter liquor; Secondly, the reason for alkali-sensitive damage in alkali-sensitive reservoirs is that conventional hydroxypropylguar - organic boron cross-linking fracturing fluids were cross-linked under alkaline environment, while the permeability of reservoirs is reduced greatly; Thirdly, the formation pressure is low, and the energy of flow back is not enough, at present, the main measure in oil fields is "injecting with liquid nitrogen", but this technique increased the cost of fracturing, making great troubles in operating, and leaving the liquid nitrogen also is a big problem.

在低压低渗透气藏的压裂改造过程中，常规羟丙基胍胶-有机硼交联压裂液体系存在的主要问题，一是压裂液滤液对低压低渗透气层造成的水锁损害；二是常规羟丙基胍胶-有机硼压裂液是在碱性条件下交联的，对碱敏性储层造成碱敏损害，降低储层渗流能力；三是地层压力低，压裂液返排能量不足，当前各油田采取的措施主要是&液氮伴注&技术，但是&液氮伴注&技术增加了压裂的费用，而且液氮存放也存在较大问题。

Although paper has to be fed and held down manually, arbitrary hold-down pressure against paper is thus available to avoid the disadvantage resulting from improper hold-down pressure The paper-cutting blade holder is driven by a motor, but it can also be operated by means of a handle to suit the needs of the location where power supply is not yet available.

本机的送纸与压纸需要手动，但压纸时，压力可任意选择，故可避免压纸的压力不适所引起的弊病。刀座切纸是由电动机驱动，但也可用手柄摇动，可适用在无电源的状态下下使用。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。