El traductor como (auto)censor: la traducción dramática en la España franquista

Eterio Pajares, Raquel Merino y José Miguel Santamaría (eds.)

应用力学进展：祝贺郑哲敏先生八十华诞应用力学报告会

    本书为祝贺郑哲敏先生八十华诞的学术报告会的文集，其中收录邀请报告12篇，定向征文58篇。这些论文涉及爆炸力学、岩土力学、冲击力学、材料力学性能、生物力学、物理力学、海洋工程力学、环境流体力学等几大方面，绝大多数为论文作者科研项目的最新成果。

 

 

力学2000

本书收录关于力学领域的论文301篇。内容包括：回顾20世纪力学在中国的发展，描绘了2000年中国和世界在力学各主要领域的发展现状；展望力学在21世纪的发展方向，探论新世纪中可能面临的新的重大力学等问题。

钱学森技术科学思想与力学

本书收录会议论文60篇。

　　本书内容大体分为三类。一类着重介绍了钱学森先生的风范，他的爱国主义，他的勤奋好学，他的治学精神和治学态度，他在学术上的重大贡献以及他的科学思想。第二类是介绍在他的领导或影响下，五十年来我国力学研究取得的成就及进一步的进展。第三类涉及我国力学界正在开展的其他方面的学术研究进展。我们的共同目的是继承优良传统，开拓我国力学在新世纪的发展。

　　读者对象：力学、航空航天、机械等领域的工程技术人员，研究人员。

郑哲敏文集

Anuario Estadistico de Pesca 1986

This document is in Spanish. El Anuario Estadístico de Pesca 1986 se compone de cinco ca pítulos que describen diferentes aspectos de la actividad pesquera. Los cuatro primeros constituyen la cobertura bá sica de las distintas fases de la actividad pesquera, desde la identificación de sus propósitos específicos, según sec tor de participación~ medios y técnicas con que se reali zan~ industrialización y comercialización Catch statistics for Mexican waters 1986. (PDF has 320 pages.)

Part 1: Longitudinal static and dynamic effects in semiconductor lasers. Part II: Spectral characteristics of passively mode-locked quantum well lasers

In the first part of this thesis a study of the effect of the longitudinal distribution of optical intensity and electron density on the static and dynamic behavior of semiconductor lasers is performed. A static model for above threshold operation of a single mode laser, consisting of multiple active and passive sections, is developed by calculating the longitudinal optical intensity distribution and electron density distribution in a self-consistent manner. Feedback from an index and gain Bragg grating is included, as well as feedback from discrete reflections at interfaces and facets. Longitudinal spatial holeburning is analyzed by including the dependence of the gain and the refractive index on the electron density. The mechanisms of spatial holeburning in quarter wave shifted DFB lasers are analyzed. A new laser structure with a uniform optical intensity distribution is introduced and an implementation is simulated, resulting in a large reduction of the longitudinal spatial holeburning effect.

A dynamic small-signal model is then developed by including the optical intensity and electron density distribution, as well as the dependence of the grating coupling coefficients on the electron density. Expressions are derived for the intensity and frequency noise spectrum, the spontaneous emission rate into the lasing mode, the linewidth enhancement factor, and the AM and FM modulation response. Different chirp components are identified in the FM response, and a new adiabatic chirp component is discovered. This new adiabatic chirp component is caused by the nonuniform longitudinal distributions, and is found to dominate at low frequencies. Distributed feedback lasers with partial gain coupling are analyzed, and it is shown how the dependence of the grating coupling coefficients on the electron density can result in an enhancement of the differential gain with an associated enhancement in modulation bandwidth and a reduction in chirp.

In the second part, spectral characteristics of passively mode-locked two-section multiple quantum well laser coupled to an external cavity are studied. Broad-band wavelength tuning using an external grating is demonstrated for the first time in passively mode-locked semiconductor lasers. A record tuning range of 26 nm is measured, with pulse widths of typically a few picosecond and time-bandwidth products of more than 10 times the transform limit. It is then demonstrated that these large time-bandwidth products are due to a strong linear upchirp, by performing pulse compression by a factor of 15 to a record pulse widths as low 320 fs.

A model for pulse propagation through a saturable medium with self-phase-modulation, due to the a-parameter, is developed for quantum well material, including the frequency dependence of the gain medium. This model is used to simulate two-section devices coupled to an external cavity. When no self-phase-modulation is present, it is found that the pulses are asymmetric with a sharper rising edge, that the pulse tails have an exponential behavior, and that the transform limit is 0.3. Inclusion of self-phase-modulation results in a linear upchirp imprinted on the pulse after each round-trip. This linear upchirp is due to a combination of self-phase-modulation in a gain section and absorption of the leading edge of the pulse in the saturable absorber.

Influence of atomic densities on propagation property for ultrashort pulses in a two-level medium

The influence of atomic densities on the propagation property for ultrashort pulses in a two-level atom (TLA) medium is investigated. With higher atomic densities, the self-induced transparency (SIT) cannot be recovered even for 2π ultrashort pulses. New features such as pulse splitting, red-shift and blue-shift of the corresponding spectra arise, and the component of central frequency gradually disappears.

A new method and instrument for accurately measuring interval between ultrashort pulses

Using second-order autocorrelation conception, a novel method and instrument for accurately measuring interval between two linearly polarized ultrashort pulses with real time were presented. The experiment demonstrated that the measuring method and instrument were simple and accurate (the measurement error <5 fs). During measuring, there was no moving element resulting in dynamic measurement error.

Ablation and ultrafast dynamics of zinc selenide under femtosecond laser irradiation

The ablation in zinc selenide (ZnSe) crystal is studied by using 150-fs, 800-nm laser system. The images of the ablation pit measured by scanning electronic microscope (SEM) show no thermal stress and melting dynamics. The threshold fluence is measured to be 0.7 J/cm2. The ultrafast ablation dynamics is studied by using pump and probe method. The result suggests that optical breakdown and ultrafast melting take place in ZnSe irradiated under femtosecond laser pulses.

Watershed monitoring and the TMDL modeling to assess bacterial loading in estuarine environments to improve management

Shellfish bed closures along the North Carolina coast have increased over the years seemingly concurrent with increases in population (Mallin 2000). More and faster flowing storm water has come to mean more bacteria, and fecal indicator bacterial (FIB) standards for shellfish harvesting are often exceeded when no source of contamination is readily apparent (Kator and Rhodes, 1994). Could management reduce bacterial loads if the source of the bacteria where known? Several potentially useful methods for differentiating human versus animal pollution sources have emerged including Ribotyping and Multiple Antibiotic Resistance (MAR) (US EPA, 2005). Total Maximum Daily Load (TMDL) studies on bacterial sources have been conducted for streams in NC mountain and Piedmont areas (U.S. EPA, 1991 and 2005) and are likely to be mandated for coastal waters. TMDL analysis estimates allowable pollutant loads and allocates them to known sources so management actions may be taken to restore water to its intended uses (U.S. EPA, 1991 and 2005). This project sought first to quantify and compare fecal contamination levels for three different types of land use on the coast, and second, to apply MAR and ribotyping techniques and assess their effectiveness for indentifying bacterial sources. Third, results from these studies would be applied to one watershed to develop a case study coastal TMDL. All three watershed study areas are within Carteret County, North Carolina. Jumping Run Creek and Pettiford Creek are within the White Oak River Basin management unit whereas the South River falls within the Neuse River Basin. Jumping Run Creek watershed encompasses approximately 320 ha. Its watershed was a dense, coastal pocosin on sandy, relic dune ridges, but current land uses are primarily medium density residential. Pettiford Creek is in the Croatan National Forest, is 1133 ha. and is basically undeveloped. The third study area is on Open Grounds Farm in the South River watershed. Half of the 630 ha. watershed is under cultivation with most under active water control (flashboard risers). The remaining portion is forested silviculture.(PDF contains 4 pages)

Intersexual and spatial heterogeneity in trophic attributes of the sleeper, Bostrychus africanus (Eleotridae) in the Qua Iboe Estuary, Nigeria

There was variation in the ingestion of the food objects by the sexes. Despite the similarity in rank-order of the food objects, the ingestion of the objects vary significantly (rg=0.320, P>0.05). Dipterans adult and Hymenoptera were the only food objects not eaten by the males whereas insect remains and unidentified bivalves were absent from the trophics spectrum of the females. There was significant increase in feeding intensity by females than males. There was significant increase in GRI by specimens from Nipa Creek whereas individuals from mangrove creek recorded higher MGF and vice-versa. Dipterans adult. Hymenoptera, insect remains, Neritina glabrata and unid bivalves were absent from dietaries for nipa creek whereas a complete array of the food objects were eaten in the mangrove creek. The present findings highlights the importance of the mangrove ecosystem as the native vegetation encompassing great diversity of food resources and living conditions than the succeeding alien nipa vegetation

飞秒双脉冲激光在硅和石英中的光学破坏

The optical breakdown thresholds (OBTs) of typical dielectric and semiconductor materials are measured using double 40-fs laser pulses. By measuring the OBTs with different laser energy and different time delays between the two pulses, we found that the total energy of breakdown decrease for silica and increase for silicon with the increase of the first pulse energy. (C) 2005 Optical Society of America.