Dynamic manipulation of nanomechanical resonators in the high-amplitude regime and non-volatile mechanical memory operation

The ability to control mechanical motion with optical forces has made it possible to cool mechanical resonators to their quantum ground states. The same techniques can also be used to amplify rather than reduce the mechanical motion of such systems. Here, we study nanomechanical resonators that are slightly buckled and therefore have two stable configurations, denoted 'buckled up' and 'buckled down', when they are at rest. The motion of these resonators can be described by a double-well potential with a large central energy barrier between the two stable configurations. We demonstrate the high-amplitude operation of a buckled resonator coupled to an optical cavity by using a highly efficient process to generate enough phonons in the resonator to overcome the energy barrier in the double-well potential. This allows us to observe the first evidence for nanomechanical slow-down and a zero-frequency singularity predicted by theorists. We also demonstrate a non-volatile mechanical memory element in which bits are written and reset by using optomechanical backaction to direct the relaxation of a resonator in the high-amplitude regime to a specific stable configuration.     

Psychological perspectives on the changing nature of retirement.

The concept and the process of retirement are rapidly evolving. As a result, psychologists are in a unique position to understand and explain the dynamics behind the changing face of retirement. We begin this article with a brief overview of the history of retirement and then note the various definitions used when studying retirement. We then propose that taking a temporal view of studying retirement would be most advantageous for psychologists. Psychological conceptualizations of retirement are then discussed, and we link these conceptualizations to studying the changing nature of retirement. Finally, we conclude with some suggestions for future research in the area of retirement that would be particularly relevant for psychologists to consider. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Temperature and composition dependent structural evolution of AgPd bimetallic nanoparticle: phase diagram of (AgPd)151 nanoparticle

We study the structural evolution of a 151 atom Ag-Pd bimetallic nanoparticle with composition and temperature. The solid-to-liquid transition region was investigated using molecular dynamics simulations with an improved collision method, and the solid-state structure of the nanoparticle was explored with a combination of molecular dynamics and density functional theory. Results show that an fcc-to-icosahedron transformation occurs at high temperature in all composition range and that a composition of nanoparticles concerns the atomic distribution of the (AgPd)151 nanoparticle. As a result, we constructed a phase diagram of the (AgPd)151 nanoparticle. Our phase diagram offers guidance on the application of Ag-Pd nanoparticles.     

Magnetic Anomalies and Spin-Glass-Like Behavior in Ce2CuGe6

A Ce-based intermetallic compound Ce₂CuGe₆ and its La analogue La₂CuGe₆ were synthesized and examined by X-ray powder diffraction, electrical resistivity, magnetic susceptibility, X-ray absorption spectrum and specific-heat measurements. The results reveal that Ce₂CuGe₆ is an antiferromagnetic Kondo-lattice compound with T _N ∼15 K. The effective moment deduced from paramagnetic region is 2.58 μ _B per cerium ion, which is close to localized Ce³⁺ free ion in ²F_5/2 state. X-ray absorption measurement also precluded the existence of an intermediate valence state. The magnetic entropy calculated from heat capacity specific-heat measurement suggested a doublet ground state. In addition, we also observed a spin-glass-like behavior in this material. The spin-glass-like behavior might be due to the complex interplay between magnetic interactions.     

液化气脱硫技术及其工业应用

阐述了无碱催化氧化脱臭、硫醇无碱转化组合技术、络合脱除技术、吸附技术、催化氧化—吸附技术、Merox抽提—氧化脱臭、纤维膜技术等液化气脱硫技术的发展现状,并说明了脱硫技术在国内多家石化企业的工业应用情况.     

Multi-Class Classification Methods of Cost-Conscious LS-SVM for Fault Diagnosis of Blast Furnace

 Aiming at the limitations of rapid fault diagnosis of blast furnace, a novel strategy based on cost-conscious least squares support vector machine (LS-SVM) is proposed to solve this problem. Firstly, modified discrete particle swarm optimization is applied to optimize the feature selection and the LS-SVM parameters. Secondly, cost-conscious formula is presented for fitness function and it contains in detail training time, recognition accuracy and the feature selection. The CLS-SVM algorithm is presented to increase the performance of the LS-SVM classifier. The new method can select the best fault features in much shorter time and have fewer support vectors and better generalization performance in the application of fault diagnosis of the blast furnace. Thirdly, a gradual change binary tree is established for blast furnace faults diagnosis. It is a multi-class classification method based on center-of-gravity formula distance of cluster. A gradual change classification percentage is used to select sample randomly. The proposed new method raises the speed of diagnosis, optimizes the classification accuracy and has good generalization ability for fault diagnosis of the application of blast furnace.     

瓦屋山水电站厂房区红层岩体古滑坡稳定性研究

红层岩体以其岩体结构的软硬相间及软弱夹层发育而在边坡稳定方面表现为"易滑地层".瓦屋山水电站厂房区边坡为顺向坡,砂岩类岩石与黏土岩类岩石呈缓倾、互层状(倾角10°～20°)产出.构造与表生改造作用下,在这两类软硬相间的岩石界面上常形成分布较为连续的软弱夹层,这类岩体较易沿软弱夹层产生顺层滑动.地质历史时期,瓦屋山厂房区就是在这样的地质背景下,形成了多个古滑坡体,如颜湾和庙子岩古滑坡,它们在自然状态下已基本稳定.随后因风化剥蚀等作用,古滑坡体形态被改变或被来自后缘斜坡的坡残积层所掩埋,使其在勘察期间难以被发现.庙子岩滑坡即是这样一个被掩埋的古滑坡体坡,施工开挖过程中,由于切脚及降雨作用,使其重新滑动复活.本文以反复剪试验得到的滑动面抗剪参数,采用边坡稳定极限分析能量法(Energy Method Upper Baond Limit Analysis),简称EMU法,对庙子岩古滑坡在各种工况下的稳定作了计算,并据其结果采取了相应的抗滑处理.本文可作为红层岩体地区该类型滑坡勘察和工程处理设计的参考.     

Emotional plasticity: Conditions and effects of improving emotional competence in adulthood.

This study aimed to investigate (a) whether it is possible to increase emotional competence (EC) in adulthood; (b) whether this improvement results in better mental, physical, and social adjustment; (c) whether this improvement can be maintained 1 year later; and (d) whether these benefits are accompanied by a reduction in stress-hormone secretion (i.e., cortisol). One hundred and thirty-two participants were randomly assigned to an EC-enhancing intervention (in group format) or to a control group. Participants in the intervention group underwent a specifically designed 15-hr intervention targeting the 5 core emotional competencies, complemented with a 4-week e-mail follow-up. Results reveal that the level of emotional competencies increased significantly in the intervention group in contrast with the control group. This increase resulted in lower cortisol secretion, enhanced subjective and physical well-being, as well as improved quality of social and marital relationships in the intervention group. No significant change occurred in the control group. Peer reports on EC and quality of relationships confirmed these results. These data suggest that emotional competencies can be improved, with effective benefits on personal and interpersonal functioning lasting for at least 1 year. The theoretical implications of these results as well as their practical implications for the construction and the development of effective emotional competencies interventions are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Analysis of characteristic aroma of fungal fermented Fuzhuan brick‐tea by gas chromatography/mass spectrophotometry

Fuzhuan brick‐tea is a popular fermented Chinese dark tea because of its typical fungal aroma. Fungal growth during the production process is the key step in achieving the unique colour, aroma and taste of Fuzhuan brick‐tea. To further understand the generation of the characteristic aroma, changes in the main volatile compounds of Fuzhuan brick‐tea during the fungal growth stage were studied by gas chromatography/mass spectrophotometry. The results showed that the content of volatile compounds, especially aldehyde compounds with stale aroma such as (E)‐2‐pentenal, (E)‐2‐hexenal, 1‐penten‐3‐ol, (E, E)‐2,4‐heptadienal and (E, Z)‐2,4‐heptadienal, increased significantly in fermented tea samples. The concentration of terpene alcohols with flower aroma also increased notably during the fermentation process. The compounds with stale and flower aromas in combination with some volatile components of the raw material contributed to the characteristic ‘fungal/flower’ aroma of Fuzhuan brick‐tea. Microbial metabolism during the fermentation process probably played the key role in the generation of characteristic aromatic compounds of Fuzhuan brick‐tea. Copyright © 2007 Society of Chemical Industry     

中浓纸浆流体化过程对纸浆性能的影响

本文在对中浓纸浆进行流体化处理后，对纸浆的主要性能参数进行检测，并通过扫描电镜观察了纤维形态的变化，从而了解中浓纸浆流体过程对纸浆性能的影响程度。