空心

Hollow sucker rod is a kind of special product designed for production of high pour point, high condensation, high paraffin crude oil. Its connector and coupling is welded with sucker rod body in friction welding. We can get the function from the hole of hollow sucker rod. The properties of hollow sucker

空心抽油杆是用于开采"高凝、高粘、高含蜡"原油的专用产品，它是将空心杆头、接箍通过摩擦焊，焊接到无缝钢管两端形成的抽油杆，其管柱内部形成一条通道，利用这一孔道实现空心抽油杆的各种功能。

The new technology makes the sucker rod string downwards easily by applying a downward hydraulic force at the bottom of the hollow sucker rod string, which effectively solves the problem of large drag force on the downstroke in the present technology of this kind.

介绍了一种新型空心杆采油工艺技术，这种技术采用了具有液力反馈原理的空心杆抽油泵，该泵的特点是能有效地减小空心杆的下行阻力，并能增加抽油杆的下行动力。

In this paper, the propagation and focus properties for several modes describing hollow beam are analyzed, and the focus properties for hollow gaussian mode are particularly discussed. Furthermore, a new mode, high-order Bessel-Gauss mode, is put forward to describe hollow beams. The results for high order Bessel-Gauss beams propagating through lens focusing system and free space are derived by terms of Collins integral formula.

本文分析了几种描述空心光束数学模型的传输特性和聚焦特性，着重讨论了描述非中空光束的数学模型的聚焦特性；同时提出了一种描述完全中空的空心光束的新模型――高阶贝赛耳高斯模型，并且运用Collins积分公式，分析了这种新模型的空心光束的传输特性和聚焦特性。

Based on the research production, with three prestressed concrete hollow slabs from the bridge in active service for ten years, this essay studies the ultimate bearing power ,the load-bearing failure mechanism and structure reenforcement measures influence on them, through examination of each performance index, failing load test, theoretical analysis and computing research work.

对预应力混凝土桥梁结构在使用中存在的问题及国内外相关研究发展水平进行了综述，指出目前对旧桥预应力混凝土空心板实际极限承载能力进行相关研究的必要性及其重大意义； 2、对旧桥预应力混凝土空心板的混凝土强度、碳化深度、预应力筋的锈蚀状况以及裂缝状况的检测评定； 3、通过破坏荷载试验，对损伤旧桥预应力混凝土空心板的受力性能进行试验评定； 4、采用在桥面做混凝土叠合层的加固措施，通过破坏荷载试验对加固后的旧桥预应力混凝土空心板的受力性能进行评定； 5、提出在役旧桥预应力混凝土空心板的维护、加固和使用建议。

Base on summarizing the development state of assembly skew hollow slab bridge, the research content of this dissertation has been determined. Taking Tuan Shan River Bridge, in Hubei province, China, as an example, the finite element method of space slab shell programmed in Ansys Parameter Design Language is adopted to analyze the elastic properties. By calculating the internal force influence surface of assembly skew hollow slab bridge, the internal force-controlling section is attained.

本文在对装配式斜交空心板桥的发展现状进行了详尽的综述后，确定了本文的研究内容，以团山河大桥为工程背景，采用ANSYS提供的参数化语言APDL，用空间板壳有限元法，对装配式斜交空心板桥弹性阶段的受力特性进行全面分析，计算了装配式斜交空心板桥的内力影响面，得到内力控制截面。

The loading program, by which the load can be directly applied to the internal force influence surface, is generated and used to get the result of loading on the influence surface. Through comparing the result of loading on the internal force influence surface of assembly skew hollow slab bridge with the one of the perpendicular bridge, the reduction factor method is offered and its corresponding reduction factor can be obtained.

编制了内力影响面加载程序实现对内力影响面的直接加载；在此基础上，通过参数分析，对比装配式正交空心板桥和斜交空心板桥内力影响面加载的结果，提出斜交空心板桥设计计算的折减系数法，并给出相应的折减系数。

Based on it, the research content of this dissertation has been determined. Tuan Shan River Bridge is selected as an example and APDL is used to analyze the elastic properties. After calculating the internal force influence surface of assembly skew hollow slab bridge, the internal force-controlling section is attained; the transverse distribution of internal force is studied and the transverse distribution coefficient is parametric analyzed. Based on the results, relation formula of transverse distribution coefficient between skew and perpendicular bridges are fitted. Practical calculation method for the internal force calculation of assembly skew hollow slab bridge is offered. Some conclusions are drawn from comparing and analysing the internal force, bearing reaction and deformation of both assembly and monolithic skew slab bridges.

本文对装配式斜交空心板桥的发展现状进行了综述，从此出发，确定了本文的研究内容，以团山河大桥为工程背景，采用ANSYS 提供的参数化语言APDL，对装配式斜交空心板桥弹性特性进行全面分析，计算了装配式斜交空心板桥的内力影响面，得到内力控制截面；同时计算了内力的横向分布影响线和横向分布系数，并对内力横向分布系数进行了参数分析；基于参数分析的结果，拟合了装配式斜交空心板桥与对应正交桥内力横向分布系数的关系式，为装配式斜交空心板桥的内力计算提供了实用计算方法；对比分析了装配式斜板桥与整体式斜板桥的内力、支座反力以及变形特点，得出了一些有益结论。

The structure and configuration did not devastated while the hematite hollow particles were deoxidizing to iron hollow particles at 500℃ in hydrogen.

壳层厚度太厚、过快和过慢的升温速率都不利于得到空心结构；500℃氢气气氛还原不改变空心粒子的形貌；空心粒子的粒径取决于聚合物模板粒子的大小，壳层厚度取决于包裹层厚度；空心铁粒子的饱和磁化强度高达到95.26 emu/g，具有较好的抗氧化能力，其磁能积可增大到1.46×103 J/m3，有利于以磁损耗为主要吸波机制的铁磁性空心粒子在吸波材料领域的应用。

The working properties of hollow rod pumping system developed on the basis of hydraulic feedback principle were analyzed.

针对液力反馈原理的新型空心杆采油工艺的特点，在理论分析的基础上，考虑液体运动、空心杆柱受力等因素的影响，完成了液力反馈型空心杆采油管柱力学分析，建立了空心杆采油的二维数学模型。

Empty hearts 2-6 rivets and solid rivets and small self-tapping screw m2-m3 and non-standard, half-empty heart rivets; flat head mid-air heart rivets; large flat head mid-air heart rivets; ping cone half-empty heart rivets; heart-empty head rivets; ping spherical Cross; semicircle Cross; and semi-head Cross; Shen Tau Cross; Pan Head Cross, enterprises attach importance to product quality.

半空心铆钉和实心铆钉2-6和小型螺丝自攻m2-m3及非标，半圆半空心铆钉；平头半空心铆钉；大扁头半空心铆钉；平锥半空心铆钉；沉头半空心铆钉；平球面十字；半圆十字；半沉头十字；沉头十字；盘头十字，企业重视产品质量。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。