NONLINEAR OPTICAL PROPERTIES OF A-SHAPED NITROPYRIMIDINE DERIVATIVES AND ITS POLYMERIC FILMS

Three A-shaped nitropyrimidine derivatives with benzyl or furfuryl as bridge havebeen synthesized. They possess shorter absorption wavelengths (λ_(cut-off))<400 nm) andhigher βμ values (around 10^(-46) esu). The second order nonlinear optical coefficient d_(33) ofpoled BNPMOPMDA/PMMA doped film is 1.2-2.0×10^(-9) esu obtained by in-situ SHGmeasurements. It can be expected that the chromophore-functionalized polymer containinghigher number density of synthesized chromophore as side chain will be the potential blue-light transparent frequency doubling materials.

AO钢板治疗Pylon骨折(附28例报告)

目的 :探讨Pylon骨折AO钢板治疗的优越性及手术要点。方法 :对 1996年 1月～ 2 0 0 0年 10月我院收治的 2 8例Pylon骨折用AO钢板进行手术治疗。结果 :2 8例获得平均 2 5个月的随诊 ,骨折全部愈合 ,总的优良率为 82 .1%。结论 :Pylon骨折应积极采取手术治疗 ,AO钢板内固定疗效佳 ,可保持植骨后胫骨高度。手术中应注意的是先整复固定外踝或后踝 ,再整复胫骨关节面并植骨 ,最后再整复内踝及支撑钢板固定 ,一期可不做关节融合。

Pylon 骨折的诊断与治疗(附45例报告)

Ｐｙｌｏｎ骨折的诊断与治疗（附４５例报告）邓昌茆文（淄博市中心医院，淄博市２５５０３６张店钢铁厂医院）关键词Ｐｙｌｏｎ骨折；内固定；植骨；踝关节融合术Ｐｙｌｏｎ骨折是指由于轴向应力造成的胫骨远端不同程度经关节面的爆裂性骨折。由于胫骨远端爆裂、远端松质...

Pylon骨折36例治疗体会

Ｐｙｌｏｎ骨折３６例治疗体会范本植，祁峰Ｐｙｌｏｎ骨折即胫腓骨远端爆裂性骨折，系胫骨远端经距小腿关节（踝关节）的骨折，有别于胫骨下１／３骨折，故被单独命名。临床工作中经常遇到这类骨折，由于对该类骨折认识不足，在治疗上常存在诸多错误，并带来不必要的并发...

PYLON骨折37例治疗体会

ＰＹＬＯＮ骨折３７例治疗体会山东济宁市第二人民医院（２７２１４９）李庆忠，刘树民我院自１９７８年２月～１９８９年５月共收治ＰＹＬＯＮ骨折病人３７例，应用中西医结合的治疗方法，取得了较为满意的效果。临床资料３７例中男３２例，女５例；年龄１３～５２岁；致...

斜拉桥易损性及极限承载力分析

以某独塔斜拉桥为研究对象,基于拉索的参数振动理论,计算分析了拉索的基频、拉索在单对断索损伤场景下的拉索应力传递系数和主梁应力安全系数;采用Pareto多目标评价方法,按结构最小损伤比例造成性能残余强度最小的优化原则,研究单对断索损伤场景下拉索的易损性,确定了易损的拉索次序和拉索对结构极限承载力的影响。分析结果表明:该斜拉桥外侧拉索更容易发生参数共振;单对拉索损伤场景下,易损拉索为主跨的Z6,Z8,Z9索;边跨单对拉索断裂对结构极限承载力影响在2%以内,主跨拉索Z6发生断裂使结构极限承载力降低14.5%。研究结果可为研究独塔斜拉桥拉索易损薄弱部位,桥梁健康监测的关键索号选取和提高结构安全性提供理论依据和参考。

The Lightweight Design of Low RCS Pylon Based on Structural Bionics

A concept of Specific Structure Efficiency (SSE) was proposed that can be used in the lightweight effect evaluation ofstructures.The main procedures of bionic structure design were introduced systematically.The parameter relationship betweenhollow stem of plant and the minimum weight was deduced in detail.In order to improve SSE of pylons, the structural characteristicsof hollow stem were investigated and extracted.Bionic pylon was designed based on analogous biological structuralcharacteristics.Using finite element method based simulation, the displacements and stresses in the bionic pylon were comparedwith those of the conventional pylon.Results show that the SSE of bionic pylon is improved obviously.Static, dynamic andelectromagnetism tests were carried out on conventional and bionic pylons.The weight, stress, displacement and Radar CrossSection (RCS) of both pylons were measured.Experimental results illustrate that the SSE of bionic pylon is markedly improvedthat specific strength efficiency and specific stiffness efficiency of bionic pylon are increased by 52.9% and 43.6% respectively.The RCS of bionic pylon is reduced significantly.

Interactive Multi-objective Optimization Design for the Pylon Structure of an Airplane

The pylon structure of an airplane is very complex, and its high-fidelity analysis is quite time-consuming. If posterior preference optimization algorithm is used to solve this problem, the huge time consumption will be unacceptable in engineering practice due to the large amount of evaluation needed for the algorithm. So, a new interactive optimization algorithm-interactive multi-objective particle swarm optimization （IMOPSO） is presented. IMOPSO is efficient, simple and operable. The decision-maker can expediently determine the accurate preference in IMOPSO. IMOPSO is used to perform the pylon structure optimization design of an airplane, and a satisfactory design is achieved after only 12 generations of IMOPSO evolutions. Compared with original design, the maximum displacement of the satisfactory design is reduced, and the mass of the satisfactory design is decreased for 22%.

3D Finite Elements Technique for Collapse Causes of the Pylons in Egyptian Temples: A Study of the Great Pylon of Ramesseum Temple, Luxor, Egypt

This research presents damage causes of the pylons in the ancient Egyptian temples based on 3D finite elements analysis. The main purpose of the research determines the failure causes of the first pylon of the Ramessium temple, which is situated in Upper Egypt, at Luxor “Thebes” on the west bank of the Nile River. The first pylon of Ramessium temple subjected to seismic activity effects on long term, combined with several structural damage factors such as the defects resulting from the construction technique, where the builder used the poor quality of stones in foundations of the pylon, the building materials residue was used as filler for the core of the pylon walls, and it lacked vertical joints between the courses. In addition to it founded on alluvial soil that is vulnerable to contaminated water, it is still suffering damage factors and urban trespasses at the moment. All of the former factors helped the pylon to be affected by the earthquakes loads that occurred on it. The structural behavior of the pylon under self-weight and earthquakes loads were carried out by Numerical analysis to find out the loads and stresses which caused collapsing of the pylon. Results of the study indicated that the pylon subjected to a horizontal displacement due to old earthquakes force, led to collapse of the pylon. Finally, the study represents use of modern technique to study the structural behavior of the most important architectural units in ancient Egyptian temples to identify the causes of its collapse.

Construction and alignment control of the middle steel pylon of Taizhou Bridge

The general construction procedure of the steel middle pylon is briefly introduced. The alignment control of the pylon is carried out during the whole process of the construction. The control concept is extended to the manufacture stage. The manufacturing alignment error is strictly controlled in the segments precast process in factory, and the error is recognized and predicted precisely during the installation stage. The adjusting joints are employed to amend the accumulated error, which ensure that the steel pylon alignment could satisfy the precision requirements after installation.

Key technology for construction of connection between steel pylonand concrete pile cap of middle pylon of Taizhou Bridge

Taizhou Bridge is a suspension bridge with three pylons and two 1 080 m main spans. The middle pylon is a steel frame with longitudinal herringbone shape and lateral gate shape. The connection between steel pylon and concrete pile cap is a key part to transfer the huge inner force from the pylon to the foundation. Its construction quality is a critical factor to the overall structural loading of the whole bridge ; therefore the contact ratio between the bearing steel plate of pylon and concrete pile cap is required to be over 75 %. The inclined joint surface in two directions, longitudinally at 39/1 920 and laterally at 1/4, posted a challenge to the construction work. A procedure test was carried out to find an optimal construction method by comparison, and finally the post-injection method was selected as it can meet the requirement of concrete strength and contact ratio at the connection. The successful application of the post-injection method in Taizhou Bridge can nrovide an examnle and reference for similar nroiects in the future.

Wind tunnel study of aerodynamic wind loading on middle pylon of Taizhou Bridge

Segment sectional model tests are carried out to investigate the wind loading on middle pylon of Taizhou Bridge, which has complicated three-dimensional flow due to its feature of double columns. Through the force measuring tests, aerodynamic force coefficients of every segment of the pylon columns have been obtained. It is found that the tested aerodynamic force coefficients are much smaller than those given by codes. The interference effects of aerodynamic force coefficients between columns of pylon are discussed. The results show that the interference effect is the most evident when the yaw angle is about 30 ° from transverse direction. This kind of interference effect can be described as diminutions in transverse aerodynamic force coefficients and magnifications in longitudinal aerodynamic force coefficients of downstream columns.

Introduction to steel pylon hoisting of Taizhou Yangtze Bridge

Taizhou Yangtze River Bridge is the first three-pylon two-span suspension bridge in the world. The middle pylon adopts deep water caisson foundation. The superstructure of the middle pylon employs herringbone shape along the bridge, and portal shape in the transverse direction for the first time in China. In this paper, the basic construction procedure, equipment, construction steps, the key construction technologies and methods of steel pylon are introduced.

Effects of Tuned Mass Damper on Wind-Induced Vibration of Free Standing Pylon by Wind Tunnel Test

In order to assess the effects of tuned mass dampers （TMDs） on wind actions, an aeroelastic model with a scale of 1：60 was constructed. Tests were performed in an atmospheric boundary layer wind tunnel to investigate the buffeting response of the pylon with a TMD fixed by a wire rope instead of a spring. The model was tested under different levels of damping. The experimental and numerical results showed that with the TMD in the optimal condition, the buffeting response was reduced by 47%.

A Study on the Quality Control of Concrete during the Slip Form Erection of Pylon

The construction market of super-high-rise buildings and long-span bridges has recognized unprecedented expansion owing to the development of high performance and high strength materials and the advances achieved in the design and construction technologies. In parallel to the lengthening and enlargement in scale of the structures, securing quality control technology of concrete while reducing the construction duration using improved construction methods emerges as a critical problem for concrete structures. In the erection of concrete pylons, slip forming represents the latest method offering the advantage of reducing drastically the construction duration compared to other methods by adopting automated slip-up of the forms and enabling 24-hour continuous placing. This study determines the slip-up time of the slip form by evaluating the early strength through the surface wave velocity and develops lightweight GFRP form in order to secure the quality of concrete during the slip form erection of pylons. A slip form system is fabricated and mockup test is conducted to verify the performances of the developed techniques through the construction of 10 m-high pylon with a hollow section.

Statistical analysis on the influence of mechanical parameters in the vibration of pylons

We present a statistical investigation of the degree of influence that assumptions made in relation to the mechanical parameters of a pylon have on its ground-induced vibrations.The study is set up by using as a key kinematic variable the displacement at the top of a reference,a stand-alone pylon with a uniform cross-section and fixity at its base.Next,statistics are produced using a dimensionless displacement ratio defined between the‘parental’and the‘subsidiary’cases,the latter defined for the pylon(a)resting on compliant soil,(b)having an attached top mass,and(c)being non-uniform with height.Furthermore,two materials are examined,namely,steel and reinforced concrete(R/C).More specifically,this displacement ratio is independent of the excitation and plays the role of a transfer function between the base and the top of the pylon.Both horizontal and vertical motions are considered,and the equations of motion are solved in the frequency domain.The ensuing statistical analysis is conducted for the following parameter combinations:(a)pylon founded on soft,intermediate,and stiff soil;(b)low,intermediate,and high-mass ratios of the attached mass to the pylon′s mass;(c)a constant and quadratic degree of pylon tapering with height.Spearman correlation coefficients are calculated for all the above combinations to arrive at statistical results that establish validity bounds and quantify the degree of influence of each assumption on the pylon′s response.