Video‐based analysis for facial skin appearance with automatic face tracking

In this article, a video‐based analysis for facial skin appearance with an automatic face tracking technique is proposed. The change of skin appearance under various illuminations is observed by illuminating the face from various light source positions, and the changes in facial appearance are recorded as a video stream during this measurement. The recorded video stream is then analyzed to obtain the bidirectional reflectance distribution function (BRDF) at each position of the facial skin. Automatic face tracking is necessary to compensate the facial movement in order to obtain an accurate BRDF measurement at each position. Since conventional face tracking techniques cannot be used for a face illuminated from various light source positions, a new face tracking technique that is robust to the various face shadings has been developed. Experimental studies show the effectiveness of both the proposed video‐based analysis technique and the automatic face tracking technique. © 2008 Wiley Periodicals, Inc. Col Res Appl, 33, 477–484, 2008     

Polarization curves in the ohmic controlled electrodeposition of metals

The conditions under which ohmic controlled metal electrodeposition occurs are discussed using a simple mathematical model. It is shown that ohmic controlled electrodeposition can be operative if the value of the exchange current density for the electrodeposition process is more than 10 times larger than the corresponding value of the limiting diffusion current density. In this case, a linear dependence of the current density on overpotential up to the value of the limiting diffusion current density can be observed. On the other hand, the initiation of dendrite growth under these circumstances is possible, even at very low values of overpotential, at the moment when the limiting diffusion current density is attained in potentiostatic electrodeposition. In this way, instead of a limiting diffusion current density plateau, an inflection point on the polarization curve can be observed, since dendritic growth is followed by an increase in the deposition current density. At the same time, it is shown that the ensemble of tips of dendrites can behave as an ensemble of microelectrodes working independently under mixed or activation control due to the absence of a common diffusion layer. This was confirmed by deposition of copper on a copper dendritic electrode and by silver electrodeposition from a silver nitrate solution onto a graphite substrate.     

Polypyrrole artificial muscles: a new rhombic element. Construction and␣electrochemomechanical characterization

A novel rhombus-shaped electrochemomechanical unit constituted by 4 polypyrrole bilayer (conducting polymer/tape) muscles and two plastic hinges, able to transform reversible angular movements from the basic bilayers into longitudinal movements, has been successfully constructed and electrochemically characterized. During operation two of the bilayers act as anode and the other two as cathode. Thus, all the electrical energy is used, avoiding an additional metallic counterelectrode and the subsequent generation of products able to degrade the muscle. The reference electrode is short-circuited to the counterelectrode in order to monitor the muscle potential along the galvanostatic experiments and the sensing abilities of the device. The devices were checked by repetitive galvanostatic contraction/extension of up to 20% of the original length. About 50% of the devices produced irregular movements, due to different ohmic resistances in the electrical contacts between the wires and polymeric films. Once the contacts were improved, the new devices showed good reproducibility. The influence of electrolyte concentration, experimental current and weight trailed by the device indicates that the complex device maintains most of the sensing properties of the basic bilayer muscles. Then checking the life-time of the device, contact failures and fissures around the metal/polymer joint were immediately detected from the chronopotentiometric noises which appeared after several cycles. Such failures must be solved before the device can be miniaturized and in order to construct different shapes, and three-dimensional sensing muscles for robotics from combinations of basic units.     

Characterization of the movement of polypyrrole–dodecylbenzenesulfonate–perchlorate/tape artificial muscles. Faradaic control of reactive artificial molecular motors and muscles

In this paper, we characterize polypyrrole–DBS–ClO₄/tape bilayers with prevalent interchange of cations, while acting as macroscopic bending artificial muscles in aqueous solution. The electrochemical origin of their movement is described by linear equations deduced from the driving Faraday's laws. We demonstrate that the engineering parameters for macroscopic bending movement rates, the direction of the movement, described angles, and final positions of the electrochemical motors, are under control of the involved current, the direction of the current flow and the consumed charge, which means under Faradaic control of the conducting polymer composition. The linear equations describing both movement rate and position were obtained. The specific (per unit of polypyrrole weight in the muscle) driving current (A g⁻¹), the specific driving charge (C s⁻¹ g⁻¹) or the specific counter-ion composition variation (mol s⁻¹ g⁻¹) are directly related to the actuator angular movement (rad s⁻¹ A⁻¹), whatever the muscle dimensions or the working polypyrrole weight in the device.     

Low Cost and Efficient Photovoltaic Conversion by Nanocrystalline Solar Cells

Solar cells are expected to provide environmentally friendly solutions to the worlds energy supply problem. Learning from the concepts used by green plants we have developed a molecular photovoltaic device whose overall efficiency for AM 1.5 solar light to electricity has already attained 10 %. The system is based on the sensitization of nanocrystalline oxide films by transition metal charge transfer sensitizers. In analogy to photosynthesis, the chemical solar cell achieves the separation of the light absorption and charge carrier transport processes. Extraordinary yields for the conversion of incident photons into electric current are obtained, exceeding 90% for transition metal complexes within the wave-length range of their absorption band. The use of molten salt electrolytes together with coordination complexes of ruthenium as sensitizers has endowed these cells with a remarkable stability making practical applications feasible. Quite aside from their intrinsic merits as photovoltaic device, the mesoscopic oxide semiconductor films developed in our laboratory offer attractive possibilities for a number Of Other applications. Thus, the first example of a briefly discussed.     

Fractional Solidification Phenomena

Abstract

Zone melting of organic compounds was observed under the microscope. A host of phenomena were noted that can greatly affect the separation attained in a fractional-solidification operation. Liquid and gaseous inclusions moved toward the melt in some systems and farther into the solid in other situations. Sometimes impure melt was sucked into the frozen solid through cracks. Insoluble foreign particles were both bounced and incorporated by freezing interfaces of camphor and anthracene. Oscillations in interface position were caused by irregular free connection both inside and outside the sample cells. Bubbles in the melt sometimes caused agitation of the melt and other times selective growth of a volatile component. Bulk drainage and falling crystals from horizontal melting interfaces were observed. During melting of camphor-anthracene mixtures some anthracene platelets grew larger.     

Influence of graphene oxide on metal-insulator-semiconductor tunneling diodes

ABSTRACT: In recent years, graphene studies have increased rapidly. Graphene oxide, which is an intermediate product to form graphene, is insulating, and it should be thermally reduced to be electrically conductive. We herein describe an attempt to make use of the insulating properties of graphene oxide. The graphene oxide layers are deposited onto Si substrates, and a metal-insulator-semiconductor tunneling structure is formed and its optoelectronic properties are studied. The accumulation dark current and inversion photocurrent of the graphene oxide device are superior to the control device. The introduction of graphene oxide improves the rectifying characteristic of the diode and enhances its responsivity as a photodetector. At 2 V, the photo-to-dark current ratio of the graphene oxide device is 24, larger than the value of 15 measured in the control device.     

Hydrogenase-catalysed deposition of vivianite on mild steel

A simple device was designed with two mild steel electrodes placed face to face in the same phosphate solution and coupled through an external electrical circuit. A dialysis membrane retained hydrogenase from Ralstonia eutropha in contact with one electrode only. The simultaneous measurements of the electron flux in the electrical circuit and of nicotinamide adenine dinucleotide (NADH) production catalysed by hydrogenase proved that the enzyme induced the occurrence of cathodic and anodic micro-sites on the same electrode surface. A clear galvanic current was observed, which stopped after a few hours, because of the formation of a protective film of vivianite on the electrode that was in contact with hydrogenase. Hydrogenase in phosphate solution proved to be an effective trigger of mild steel corrosion. These results may be the basis of a new and easy-to-handle hydrogenase-catalysed phosphating process, which operates under mild conditions, avoids using toxic compounds, and is quite rapid.     

Effect of silane functionalized alumina on poly(vinyl butyral) nanocomposite films: Thermal,mechanical, and moisture barrier studies

In this work, a hybrid‐polymer nanocomposite film, based on polyvinyl butyral/amino‐silane functionalized nano alumina, was fabricated by melt processing. The calcium degradation measurements suggest the functionalized nanocomposite films exhibit higher resistance towards moisture penetration as compared to the neat alumina loaded films. Thermal stability, mechanical strength, and contact angle studies of the composites were also conducted to evaluate the performance of the functionalized alumina loaded films. These nanocomposite films were encapsulated over Al/P3HT/ITO Schottky structured device. The changes observed in the current density of the devices to the applied voltage before and after accelerated aging conditions are presented. The nanocomposite with functionalized alumina films exhibits 50% change in current density, which is superior to that attained with neat and non‐functionalized films. POLYM. COMPOS., 35:1426–1435, 2014. © 2013 Society of Plastics Engineers     

唐山氯碱项目双30万t/a 一期工程整流系统运行总结

介绍了一种优秀的国产变压整流设备,特别介绍了它所采用的三相全控桥同相逆并联连接方式,有载调压(开关粗调)、晶闸管细调运行方式。该设备已应用于日本旭化成工艺的离子膜食盐电解系统,且一次性开车成功,各项技术指标均达到(有些已经超过)行业标准,生产能力优于设计能力,并取得了显著的经济效益。     

Kinetic and thermodynamic approaches for the efficient formation of mechanical bonds

Among the growing collection of molecular systems under consideration for nanoscale device applications, mechanically interlocked compounds derived from electrochemically switchable bistable [2]rotaxanes and [2]catenanes show great promise. These systems demonstrate dynamic, relative movements between their components, such as shuttling and circumrotation, enabling them to serve as stimuli-responsive switches operated via reversible, electrochemical oxidation-reduction rather than through the addition of chemical reagents. Investigations into these systems have been intense for a number of years, yet limitations associated with their synthesis have hindered incorporation of their mechanical bonds into more complex architectures and functional materials. We have recently addressed this challenge by developing new template-directed synthetic protocols, operating under both kinetic and thermodynamic control, for the preparation of bistable rotaxanes and catenanes. These methodologies are compatible with the molecular recognition between the pi-electron-accepting cyclobis(paraquat-p-phenylene) (CBPQT(4+)) host and complementary pi-electron-donating guests. The procedures that operate under kinetic control rely on mild chemical transformations to attach bulky stoppering groups or perform macrocyclizations without disrupting the host-guest binding of the rotaxane or catenane precursors. Alternatively, the protocols that operate under thermodynamic control utilize a reversible ring-opening reaction of the CBPQT(4+) ring, providing a pathway for two cyclic starting materials to thread one another to form more thermodynamically stable catenaned products. These complementary pathways generate bistable rotaxanes and catenanes in high yields, simplify mechanical bond formation in these systems, and eliminate the requirement that the mechanical bonds be introduced into the molecular structure in the final step of the synthesis. These new methods have already been put into practice to prepare previously unavailable rotaxane architectures and novel complex materials. Furthermore, the potential for utilizing mechanically interlocked architectures as device components capable of information storage, the delivery of therapeutic agents, or other desirable functions has increased significantly as a result of the development of these improved synthetic protocols.     

短切麻纤维无纺针刺毡的制备研究

为了把麻纤维用作复合村料的增强体,本文在针刺制毡设备上制备了短切苎麻、黄麻纤维无纺针刺毡,并对利用这种现有工业设备制备麻纤维毡的工艺条件进行了研究,测试了麻毡的有关性能.结果表明,适当改变工艺参数,利用现有工艺业针刺设备可以制备短切麻纤维毡.制备的短切麻纤维无纺针刺毡面密度和厚度分布均匀,满足使用要求.     

声悬浮反应器的设计与控制

介绍了作者为研究气固或气液体系单颗粒的物理和化学变化过程而研制的声悬浮反应器的设计和控制。该反应器除作为主体的单轴谐振式声悬浮装置外，还包括通过自动调节腔长，维持腔室谐振的谐振跟踪系统，与谐振跟踪系统同时作用，通过相对于窗口平移谐振腔室崦使颗粒稳定悬浮在对准窗口的颗粒位置控制系统，ＣＯ２激光加热系数，红外辐射测温系统?以及为实时控制颗粒温度和位置及采集颗粒图象的微机系统。文中详细叙述了谐振跟踪和颗     

Tunneling Current-Voltage Controls,Oscillations, and Instability of Nanotube- and Nanowire-Based Nanoelectromechanical Systems

In this paper, vibrations, instability, and control of nanotube- and nanowire-based nanoelectromechanical systems (NEMS) are investigated. A dynamic analysis is presented, which includes the role of the electric field, van der Waals forces, temperature, and the uncertainty principle. Furthermore, the system instability, arising at the so-called pull-in voltage and corresponding to the on-off transition of the device, is also quantified. Active current and voltage controls based on the quantum tunneling effect are discussed. It is shown that the tunneling current between the cantilever nanotube/nanowire tip and the electrode substrate would correspond to the realization of an analogic device (e.g., nanotweezers) if the current is in control or to a digital device (e.g., nanoswitch) if the voltage is controlled. Finally, the characteristic electromechanical curves voltage/current-displacement for the NEMS are deduced.Original English Text Copyright © 2005 by Fizika i Khimiya Stekla, Pugno.This article was submitted by the author in English.     

恒电流密度滚镀锌试验研究

设计了一种适合滚镀的电流密度传感与测试装置,采用全数字控制的高频开关电源,在恒电流密度下进行了滚镀锌闭环控制试验研究。结果表明:在相同工件、相同时间的条件下,恒电流密度闭环控制模式比恒电压模式节能10%,且膜厚均值较大;随着电镀时间延长,恒电流密度闭环控制模式下的镀层厚度变化趋于平缓,但镀层厚度分散程度较恒电压控制模式时大。     

管形器件电镀的物理模拟

电镀过程中阴阳极板间的电压、电场,溶液中的电流及板上面电荷密度之间的内在联系是电镀研究中常常忽视的一个物理问题。利用物理模型模拟待镀管形器件双面镀的影响因素,得到了在电镀过程中器件尺寸大小及安置位置等的规律：要得到均匀的镀层,应使内阳极极棒的半径大于镀件半径的一半且靠近镀件,同时减小溶液中的离子浓度。     

Performance of a non‐load‐bearing steel stud gypsum board wall assembly: Experiments and modelling

A gypsum wall assembly was exposed to an intense real‐scale compartment fire. For the wall assembly, temperatures were measured at the exposed face, within the stud cavity, and at the unexposed face during the fire exposure. Total heat flux gauges were used to measure the temporal variation of the energy incident on the walls, and cameras, both visual and infrared, were used to image the unexposed face of the wall assembly during the fire exposure. The behaviour of the wall assembly under the fire load is discussed as are current model results for a simulation of the fire test. Copyright © 2006 John Wiley & Sons, Ltd.     

整流子对错流移动床颗粒行为的影响

在矩形错流移动床中考察了整流子对移动床内颗粒移动、空腔、贴壁等现象的影响. 实验结果表明，在有错流的条件下，床层内颗粒下移速度表现为近上游面的颗粒快于近下游面的颗粒，适当调整整流子位置有可能使床层内颗粒在某一气速下以几乎相同的速度下移. 与无整流子的装置相比，整流子的设置能推迟移动床空腔的生成并减小空腔尺寸，其横向位置离上游面越远对空腔影响越小；但设置整流子将降低错流移动床的贴壁临界值，其横向位置离上游面越远对贴壁影响越大. 为定量描述空腔尺寸和贴壁临界值，将床层简化为由整流子中心位置决定的2个虚拟流道，并分别建立了数学模型，模型计算值与实验值大致相符.     

Electrochemical synthesis of poly(ortho-ethoxyaniline) from phosphoric and sulphuric acid solutions

The growth and nucleation mechanism of poly(ortho-ethoxyaniline) (POEA) are investigated by cyclic voltammetry (CV) and potentiostatic technique. It was shown that growing of POEA is faster in sulphuric acid solution compared to phosphoric acid solution. Different rate trends were obtained with the increase of switching potential. From cyclic voltammograms, it is evident that the obtained polymer has a similar behaviour to the one reported for polyaniline, but there is a difference in position of current peaks, due to the electronic and steric effects of ethoxy-group. In presence of different anions, a different nucleation mechanism was obtained. In sulphuric acid solution nucleation proceeds through 3D instantaneous nucleation under diffusion control, and in phosphoric acid solution nucleation proceeds through 3D progressive nucleation under diffusion control.     

事故氯引风机连锁装置

从经济、安全、环保等方面分析现有事故氯风机连锁装置不足之处。比较2种止回装置——加装自控阀和添加水封装置的优缺点,选用风机出口水封装置代替自控阀实现风机互相切换,将风机出口至水面的垂直高度提高至1 000 mm,将出口管道浸入水中的深度由300 mm改为50 mm,很好地解决了启动、运行电流高的问题。实践证明,该装置不但能保证安全环保,而且投入少、维护方便、运行成本低,能达到良好的使用效果。