两个冠醚分子在简正坐标分析及NRCC程序在微机上的移植

本文用加拿大国立研究院(National Research Council of Canada) Fuhrer等人编制的FORTRAN语言程序（以下简称NRCC程序），对两个冠醚类化合物进行了简正坐标分析，这两个化合物分子是二氧六环(C_4H_8O_2)和12－冠－4(C_8H_(16)O_4)。作者用Synder和Zerbi提出的一般价力场，计算了二氧六环的36个简正振动频率，精化四次后的结果误差为14.04 cm~(-1)，得到了二氧六环的精化力场和势能分析矩阵；做了12－冠－4－的中红外光谱(3200-5000cm~(-1))。远红外光谱(500-70cm~(-1))和拉曼光谱(3200-50 cm~(-1)，从而归属出12－冠－4的78个简正振动频率实验值；利用二氧六环的精化力场作为初始力场，计算了12－冠－4的简正振动频率，对78个简正振动频率进行了精化计算，精化三次后的结果误差为13.99 cm~(-1)，精化后得到12－冠－4的精化力场和势能分布矩阵；将NRCC程序以BASIC语言移至TRS-80微型机上，对二氧六环进行了计算，结果良好，首次给出二氧六环一般价力场的势能分布。一、对二氧六环的处理 二氧六环分子式C_4H_8O_2，合14个原子，有3N－6＝36个简正振动频率。分子结构系由二个乙氧基(-CH_2-CH_2-O-)单元组成的含有四个碳，两个氧的六元环，平衡态分子为椅式构象，属于C_(2h)点群，36个简正振动频率分为四个对称类Ag、Au、Bg和Bu，分布是：Ag 10个，Bg 8个，Au 9个，Bu9个。二氧六环的分子结构及坐标示意图见28而图5，定义了14个伸缩内坐标，26个弯曲内坐标，6个扭曲内坐标，共46个，C－C键长1.54A，C-O键长1.41 A，C－H键长1.096A，键角都用109°28'。用CART程序（NRCC程序之一）计算二氧六环14个原子的笛卡尔坐标，用GMAT程序（NRCC程序之二）计算其B矩阵和G矩阵，用FPERT程序（NRCC程序之三）计算其简正振动频率、精化力场，计算用一般价力场，引入V矩阵对称化，将46个坐标化为46个（内）对称坐标，10个多余坐标在FPERT程序计算中除去。二、对12－冠－4的处理 12－冠－4分子式C_8H_(16)O_4，含28个原子，共3N－6＝78个简正振动频率，分子结构为四个乙氧基(-CH_2-CH_2-O-)单元组成的含八个碳、四个氧的12元环，自由分子的12－冠－4属于C点群。结构数据引自Groth的X光衍射分数和坐标，自己编制了BASIC语言程度将分数坐标化为笛卡尔坐标，用GMAT程序计算B矩阵和G矩阵，FPERT程序计算78个简正振动频率、精化力场、计算势能分布矩阵，引入U矩阵将92个内坐标化为92个对称坐标，14个多余坐标在FPERT程序中自动除去。三、结果 势能分布矩阵给出分子的振动归属，对这两个冠醚类分子的3N－6个简正振动频率，可以划分为五个振动区域。1．C－H伸缩振动区（3000－2800 cm~(-1)） 在该区中，二氧六环有八个值：2974、2966、2854和2867 cm~(-1)各两个，12－冠－4有16个值：2935、2923、2915和2907 cm~(-1)各两个，2860 cm~(-1)8个，高于2900 cm~(-1)者为反对称伸缩振动，低于2900 cm~(-1)者为对称伸缩振动。2．亚甲基弯曲振动之一(1500-1400 cm~(-1)) 该区的主要振动是亚甲基剪式振动(Scissor)，其它振动小于10％二氧六环在该区有四个频率：1443、1461、1451和1457 cm~(-1)，12－冠－4有八个频率：1466、1450、1450和1405 cm~(-1)各两个。3．亚甲基弯曲振动区二(1400-1200 cm~(-1))该区的主要振动模式为亚甲基的颤动(wag)、卷曲(twist)和摆动(rock)振动，其它振动小于13％。二氧六环在该区有八个频率：1334、1303、1396、1216、1367、1264、1377和1296 cm~(-1)，12－冠－4有十六个频率：1388、1363、……1229 cm~(-1)（其中1288、1307cm~(-1)非简并，其余皆两重简并）。4．环的骨架伸缩振动区(1200-600 cm~(-1))该区振动模式复杂，除环的骨架伸缩振动外，还有亚甲基的wag、twist、rock以及环的骨架弯曲振动，而且这些振动的势能分布值都不小。二氧六环在该区有十一个频率，从1127至610 cm~(-1)，12－冠－4有二十个频率，从1135至184 cm~(-1)且大都是二重简并的。5．低频区(600-50cm~(-1))这两个分子在低频区的势能分布略有差别。二氧六环在该区有五个频率：503、486、427、276和224 cm~(-1)，主要振动模式为骨架弯曲振动和扭曲振动，C－O、C－C的扭曲振动在三个最低频率中分布占10－30％。12－冠－4在该区有18个频率，除570和547cm~(-1)处，都是二重简并的，六个最低频率的振动模式完全属于C－O、C－C键的扭曲振动，其它振动小于10％，所以200 cm~(-1)以下可称为12－冠－4的扭曲振动区，在600－200cm~(-1)之间的12个频率主要是骨架的弯曲振动，也有一定量的亚甲基wag、twist、rock振动。12－冠－4的简正坐标分析尚未有人做过。二氧六环的计算结果与Snyder和Zerbi的分析相吻合，12－冠－4和二氧六环两分子势能分布的相对一致性证明了对12－冠－4的简正坐标分析基本是正确的。本文比较了二分子的力常数和振动频率，探讨了环的大小对振动光谱的影响。四、NRCC程序简介 NRCC程序由CART、GMAT和FPERT三个程序组成，即可联一起运用，亦可分开独立进行运算。该程序功能强，所占内存大，适于大、中型计算机使用。CART程序之名字取自Cartisian Co-or-dinates的前四个字母，功能系由分子结构参数（键长、键角）计算分子内各原子的笛卡尔坐标。GMAT程序之名字取自G matrix的前四个字母，功能系由分子内各原子的笛卡尔坐标，原子质量和内坐标定义计算分子内各原子的坐标交换矩阵B和Wilson振动动能矩阵G。FPERT程序之名字取自F Perturbation的前五个字母，功能系由分子振动功能矩阵G、势能常数即力常数矩阵F计算分子的简正振动频率和势能分布矩阵，再通过实验频率精化势能矩阵F。NRCC程序可对含30个原子、60个内坐标的分子进行简正坐标分析，扩充后容量增大一倍。该程序可选用一般价力场(General Valence Force Field, 简称GVFF)和UBS���场(Urey-Bradley-Shimanouchi Force Field)，简称UBSFF或UBFF)。可选用对称化U矩阵，可自行决定力场精化次数和阻尼常数以限制精化结果的收敛性。五、NRCC程序在TRS－80微型机上移植试尝（该部分曾在第三届长春夏季化学讨论会上宣读）针对NRCC程序占内存空间大、难以在微型机上实现的情况，作者将NRCC程序改编为BASIC语言，改变程序的原来结构，形成一组BASIC语言程序：CART／BAS、GMAT／BAS和VIFR／BAS，改编后的BASIC程序在TRS－80微型机调试通过，TRS－80机字长8位，New Dos系统内存32K。改写后的程序只保持了原程序的基本原理，在内存，语句上改动很大，以适于微型机使用。数据在程序中直接嵌入，利于修改替换，且BASIC语言简单易学，便于操作。CART／BAS程序可计算含30个原子以内的分子的笛卡尔坐标，GMAT／BAS程序可计算含20个原子、45个内坐标的分子的G矩阵，VIFR／BAS程序可计算含15个原子的分子的简正振动频率。利用这组程序，作者以二氧六环分子为例做了一些试尝运算，误差14.4 cm~(-1)，相对误差1.8%，结果较理想。

小型无人直升机实验平台的设计与实现

高级控制算法对于无人直升机实现高机动性非常重要,但是在实现上也经常受制于鲁棒性和实时性的要求。同时这些控制方法在飞行测试时也会带来高风险。本文介绍了一种自制的安装在机械臂上的直升机作为实验平台去验证控制方法的有效性和可行性,这个平台还能够保证飞行测试的安全性。实验结果显示,能够实现转速跟踪控制以及航向动力学的辨识,并证明平台的有效性。

Asynchronous Auction for Distributed Nonlinear Resource Allocation Problem

Resource Allocation Problems (RAPs) are concerned with the optimal allocation of resources to tasks. Problems in fields such as search theory, statistics, finance, economics, logistics, sensor & wireless networks fit this formulation. In literature, several centralized/synchronous algorithms have been proposed including recently proposed auction algorithm, RAP Auction. Here we present asynchronous implementation of RAP Auction for distributed RAPs.

Controlling the second harmonic in a phase-matched negative-index metamaterial.

Nonlinear metamaterials have been predicted to support new and exciting domains in the manipulation of light, including novel phase-matching schemes for wave mixing. Most notable is the so-called nonlinear-optical mirror, in which a nonlinear negative-index medium emits the generated frequency towards the source of the pump. In this Letter, we experimentally demonstrate the nonlinear-optical mirror effect in a bulk negative-index nonlinear metamaterial, along with two other novel phase-matching configurations, utilizing periodic poling to switch between the three phase-matching domains.

Electronically reconfigurable metal-on-silicon metamaterial

This work was supported by Toyota Motor Engineering and Manufacturing North America and partially supported by the Air Force Office of Scientific Research (Grant No. FA9550-09-1-0562).

Probing the ultimate limits of plasmonic enhancement.

Metals support surface plasmons at optical wavelengths and have the ability to localize light to subwavelength regions. The field enhancements that occur in these regions set the ultimate limitations on a wide range of nonlinear and quantum optical phenomena. We found that the dominant limiting factor is not the resistive loss of the metal, but rather the intrinsic nonlocality of its dielectric response. A semiclassical model of the electronic response of a metal places strict bounds on the ultimate field enhancement. To demonstrate the accuracy of this model, we studied optical scattering from gold nanoparticles spaced a few angstroms from a gold film. The bounds derived from the models and experiments impose limitations on all nanophotonic systems.

Far-field analysis of axially symmetric three-dimensional directional cloaks.

Axisymmetric radiating and scattering structures whose rotational invariance is broken by non-axisymmetric excitations present an important class of problems in electromagnetics. For such problems, a cylindrical wave decomposition formalism can be used to efficiently obtain numerical solutions to the full-wave frequency-domain problem. Often, the far-field, or Fraunhofer region is of particular interest in scattering cross-section and radiation pattern calculations; yet, it is usually impractical to compute full-wave solutions for this region. Here, we propose a generalization of the Stratton-Chu far-field integral adapted for 2.5D formalism. The integration over a closed, axially symmetric surface is analytically reduced to a line integral on a meridional plane. We benchmark this computational technique by comparing it with analytical Mie solutions for a plasmonic nanoparticle, and apply it to the design of a three-dimensional polarization-insensitive cloak.

Conservative Interventions for mobile Pes Planus in Adults: a systematic review

Antecedentes. Pes Adulto planus (pie plano) es un problema común encontrado por muchos profesionales de la salud. A pesar de la percepción de que el pie plano puede causar dolor y deteriorar su función, la disponibilidad y el uso generalizado de diversos tratamientos, no hay consenso sobre la estrategia óptima de tratamiento. Objetivo. Evaluar la efectividad de las intervenciones conservadoras (no quirúrgicos) para pie plano en los adultos. Método. Se realizó una búsqueda sistemática de la literatura. Esto incluye: el Registro Cochrane Central de Ensayos Controlados; los Juicios CMSG Especializados Registro; una búsqueda electrónica se realizó utilizando MEDLINE (1960 a junio de 2012), EMBASE (1980 a junio de 2012), y CINAHL (1982 - junio de 2012). Revistas especializadas, listas de referencias de ensayos y artículos de revisión se realizaron búsquedas manuales. Criterios de selección: Ensayos aleatorios o cuasialeatorios de intervenciones de tratamiento para el pie plano en los adultos. Se excluyeron los ensayos que incluyeron patologías específicas como el dolor plantar del talón, las fracturas por sobrecarga de los metatarsianos, disfunción del tendón tibial posterior-, fracturas de tobillo, patologías del pie reumatoide, enfermedades neuromusculares y las complicaciones del pie diabético. Recopilación y análisis de datos: Dos autores seleccionaron de forma independiente los resultados de la búsqueda para identificar a aquellos que satisfacen los criterios de inclusión y evaluaron la calidad de los incluidos mediante una lista de control basado en la Evaluación de la Colaboración Cochrane de Riesgo. Esta herramienta se centró en el riesgo de la selección, el rendimiento, la detección, la heterogeneidad y el sesgo de notificación. Resultados. Cuatro ensayos, con 140 sujetos, cumplieron los criterios de inclusión para la revisión. Los cuatro fueron juzgados como de alto riesgo de sesgo en al menos un área, y también estaban en riesgo de sesgo incierto en al menos otra zona. Todos anotaron altamente en relación al sesgo de deserción, debido al corto seguimiento tiempos y diseños experimentales utilizados. Los datos no se agruparon debido al alto nivel de heterogeneidad identificada en las intervenciones evaluadas, los participantes seleccionados y medir los resultados. Los resultados de un estudio sugieren que después de cuatro semanas de uso ortesis puede resultar en una mejora significativa en vaivén lateral medio, y pueden resultar en una mejor, aunque no significativa, en general relacionados con la calidad de vida de los pies (Roma 2004). Un estudio (Redmond 2009) sugiere que su efecto sobre la distribución de la presión plantar en el pie puede no depender de si son personalizados o dispositivos prefabricados. Aunque este estudio se identificaron cambios significativos en algunas variables de presión plantar tanto con la costumbre y dispositivos prefabricados, otro (Esterman 2005) no encontró ningún efecto significativo de longitud ¾ ortesis prefabricadas sobre el dolor, la incidencia de lesiones, salud pie o de calidad de vida en un grupo de reclutas de la fuerza aérea. El cuarto estudio (Jung 2009) sugiere que el ejercicio de los músculos intrínsecos del pie puede mejorar el efecto de las ortesis. A pesar de estos resultados, ya que cada estudio incurrió riesgo de sesgo en al menos un área no se pueden sacar conclusiones

Reducing Uncertainty in Aeroelastic Flutter Boundaries Using Experimental Data

Flutter prediction as currently practiced is usually deterministic, with a single structural model used to represent an aircraft. By using interval analysis to take into account structural variability, recent work has demonstrated that small changes in the structure can lead to very large changes in the altitude at which
utter occurs (Marques, Badcock, et al., J. Aircraft, 2010). In this follow-up work we examine the same phenomenon using probabilistic collocation (PC), an uncertainty quantification technique which can eficiently propagate multivariate stochastic input through a simulation code,
in this case an eigenvalue-based fluid-structure stability code. The resulting analysis predicts the consequences of an uncertain structure on incidence of
utter in probabilistic terms { information that could be useful in planning
flight-tests and assessing the risk of structural failure. The uncertainty in
utter altitude is confirmed to be substantial. Assuming that the structural uncertainty represents a epistemic uncertainty regarding the
structure, it may be reduced with the availability of additional information { for example aeroelastic response data from a flight-test. Such data is used to update the structural uncertainty using Bayes' theorem. The consequent
utter uncertainty is significantly reduced across the entire Mach number range.

Status and security: how Russian media is spinning airstrikes in Syria

Even before the Russian air force launched its first strikes over Syria, there was already a Russian presence on the battleground. These were not the spetsnaz, Kremlin’s special forces, but war correspondents from the leading Russian media outlets. This was as clear a sign as any that the Russia’s priority has shifted from Ukraine, where these reporters spent most of the past 18 months, to Syria.

There is, however, no unanimity on Russia’s latest escalation in Syria. As Russian state TV stations report successes of Russia’s high-precision weapons projecting an image of a high-tech Russian military equal to the US, doubts persist about the latest adventure in the Middle East.

A Força Aérea Portuguesa e o voo nas redes sociais

Trabalho de projeto apresentado à Escola Superior de Comunicação Social como parte dos requisitos para obtenção de grau de mestre em Publicidade e Marketing.

Developing and implementing an environmental performance index for the Portuguese military

Business Strategy and the Environment nº 15, p. 71–86

Estudo relativo à utilização dos Equipamentos de Medida e Precisão (EMP) nas ações de manutenção da frota F-16

Esta dissertação foi realizada, tendo como objecto de estudo a utilização de equipamentos de Medida e Precisão, em diversas áreas da manutenção da Base Aérea Nº 5. Como hipótese de trabalho, no âmbito da dissertação do Mestrado de Engenharia Instrumentação e Metrologia, foi proposta a elaboração de um estudo, tendo em vista, uma melhoria das capacidades da organização demonstrar certos requisitos no âmbito da gestão e controlo de equipamentos de Medida e Precisão. Assim, a metodologia utilizada para a realização desta dissertação, partiu da análise do estado da arte nas normas internacionais, da regulamentação emitida pela Força Aérea Portuguesa e no estudo das práticas em uso na manutenção da Base Aérea Nº 5, assim como, nos atuais meios de execução e controlo dessa gestão num sistema integrado de “gestão de conteúdos”. Foram realizados diversos trabalhos, tendo como objectivo uma melhoria no processo de gestão de Equipamentos de Medida e Precisão, com resultados imediatos, tais como um novo portal de metrologia, e-mail de informação sobre Equipamentos de Medida e Precisão e certificados digitais. Seguidamente, forma apresentados os resultados do estudo e demonstrada a necessidade de implementar um processo de recall, para as acções onde são usados Equipamentos de Medida e precisão. Na dissertação, são utilizadas terminologias aeronáuticas, por as mesmas serem comuns no seio da organização, assim como, consonantes com a prática usual na indústria de manutenção aeronáutica militar no mundo.

Fleet Industries records, 1948, 1983-1989

The Fleet Aircraft of Canada Ltd. Company was founded in 1930 by Reuben Hollis Fleet in Fort Erie, Ontario. Within the first decade of operations, the company had gained an international reputation for excellence. With the outbreak of war in 1939, Fleet focused all of its efforts in the design and production of various training aircraft for the Royal Canadian Air Force and the refurbishment of British and Canadian fighter planes. Fleet ceased production of aircrafts in 1957 and was renamed Fleet Aerospace, a division of Magellan Aerospace. The manufacturing location in Fort Erie was known as Fleet Industries. Currently, the company is a Canadian Aerospace Sub-contractor that manufactures aerospace structures, component parts, and assemblies to approved design data. Fleet’s customers include Boeing, Bombardier, Viking Air and Erickson Air-Crane. In 2006, the Company became privately owned when 16 minority stakeholders took over operations. The Company was renamed Fleet Canada Inc.

Atténuation de la dépression post-infarctus par une diète riche en oméga-3 ou par la prise de probiotiques

L'Infarctus du myocarde (IM) provoque, chez le rat, une augmentation de l'apoptose dans le système limbique en plus d'induire des symptômes qui s'apparentent à la dépression chez l'humain. Nous avons démontré qu'une diète élevée en oméga-3 ou la prise de probiotiques pouvaient être efficaces pour réduire ces effets si ces interventions débutaient avant l'induction de l'ischémie myocardique. Cette étude a pour objectif de déterminer l'efficacité de ces interventions si elles débutent après l'ischémie myocardique. L’IM a été induit chez le rat mâle Sprague-Dawley par l’occlusion de l’artère coronaire descendante antérieure gauche pendant 40 minutes. À la suite de l’ischémie, les rats ont reçu des probiotiques (1 billion de bactéries vivantes de L. helveticus R0052 et de B. longum R0175) ou un véhicule dans leur eau de boisson en présence d'une diète élevée ou faible en oméga-3. À 3 jours post-IM, l’activité enzymatique de la caspase-3 et le nombre de cellules dUTP nick-end labelling (TUNEL) positives sont diminués dans les régions CA1 et le corps godronné de l’hippocampe ainsi que dans l’amygdale en présence de la diète élevée en oméga-3. La prise de probiotiques atténue également l’activité de la caspase-3 et le nombre de cellules TUNEL positives dans le corps godronné et l’amygdale médiane. À 2 semaines post-IM, le comportement dépressif évalué par 3 tests comportementaux (test d’interaction sociale, test de nage forcée et test d’évitement passif) a été observé chez le groupe recevant la diète faible en oméga-3 sans probiotiques et le comportement dépressif a été atténué avec la diète élevée en oméga-3 et/ou la prise de probiotiques. Les probiotiques ont augmenté les niveaux plasmatiques d’interleukine-4 (IL- 4) tandis que la diète élevée en oméga-3 a montré une diminution de la protéine chimiotactique monocytaire 1 (MCP-1). Ces résultats indiquent qu’une diète élevée en oméga-3 ou la prise de probiotiques, débutant à la suite de l’IM, s’avèrent bénéfiques pour atténuer la dépression et l’apoptose dans le système limbique.