Search

One of the main diagnostic tools for measuring electron density profiles and the characteristics of long wavelength turbulent wave structures in fusion plasmas is Beam Emission Spectroscopy (BES). The increasing number of BES systems necessitated an accurate and comprehensive simulation of BES diagnostics, which in turn motivated the development of the RENATE simulation code that is the topic of this paper. RENATE is a modular, fully three-dimensional code incorporating all key features of BES systems from the atomic physics to the observation, including an advanced modeling of the optics. Thus RENATE can be used both in the interpretation of measured signals and the development of new BES systems. The most important components of the code have been successfully benchmarked against other simulation codes. The primary results have been validated against experimental data from the KSTAR tokamak., Comment: 8 pages, 10 figures

Inorganic LiNbO 3 ion conducting films were prepared by sol-gel process involving two alkoxides, lithium ethoxide and niobium ethoxide. The films were analyzed by ellipsometry, X-ray diffractometry, scanning electron microscopy and impedance spectroscopy. Impedance spectroscopy indicated that the Li ÷ conductivity values were in the range of 6-8 × 10 -7 S cm -1. The morphology and thickness of these films played an important role in the insertion of lithium ions. Spectrophotometric investigation showed that LiNbO 3 films exhibit very weak cathodic coloration from 350 to 900 nm spectral region. The electrochemical and optical properties clearly indicate that sol-gel deposited LiNbO 3 films can be used as lithium ion conducting layers for electrochromic device application.

Niobium pentoxide films, fabricated by the sol-gel process, were spin coated onto conductive indium tin oxide (ITO)/glass, and microscope slides. These films were cycled in a 1 M LiC104 propylene carbonate (PC) solution, and exhibited electrochromic behavior upon the electrochemical insertion (reduction) and extraction (oxidation) of lithium. In-situ optical transmittance measurements were investigated in the ultra-violet/visible near-infrared wavelength regions (250–2100 nm). Niobium pentoxide films showed reversible optical switching from 320 to 870 nm, but were found electrochromically inactive in the infrared region. Surface analysis using X-ray photoelectron spectroscopy (XPS) indicated little difference in the chemistry of Nb2O5 films as deposited and lithiated Lix,Nb2O5 films, as XPS binding energies of Nb and O showed no appreciable shifts. These films were found to be amorphous by X-ray diffraction. Optical transmittance measurements combined with cyclic voltammograms and XPS spectra, revealed that the electrochromic behavior of these films occurs due to the insertion of Li+ cations into niobium pentoxide films. The bronze coloration of the niobium pentoxide films could make them useful as an electrochromic counter electrode for electrochromic devices.

BACKGROUND: Dietary fluoride supplements were first introduced to provide systemic fluoride in areas where water fluoridation is not available. Since 1990, the use of fluoride supplements in caries prevention has been re‐evaluated in several countries. OBJECTIVES: To evaluate the efficacy of fluoride supplements for preventing dental caries in children. SEARCH METHODS: We searched the Cochrane Oral Health Group's Trials Register (to 12 October 2011), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 3), MEDLINE via Ovid (1950 to 12 October 2011), EMBASE via Ovid (1980 to 12 October 2011), WHOLIS/PAHO/MEDCARIB/LILACS/BBO via BIREME (1982 to 12 October 2011), and Current Controlled Trials (to 12 October 2011). We handsearched reference lists of articles and contacted selected authors. SELECTION CRITERIA: We included randomised or quasi‐randomised controlled trials comparing, with minimum follow‐up of 2 years, fluoride supplements (tablets, drops, lozenges) with no fluoride supplement or with other preventive measures such as topical fluorides in children less than 16 years of age at the start. The main outcome was caries increment measured by the change in decayed, missing and filled tooth surfaces (DMFS). DATA COLLECTION AND ANALYSIS: Two review authors, independently and in duplicate, assessed the eligibility of studies for inclusion, and carried out risk of bias assessment and data extraction. In the event of disagreement, we sought consensus and consulted a third review author. We contacted trial authors for missing information. We used the prevented fraction (PF) as a metric for evaluating the efficacy of the intervention. The PF is defined as the mean caries increment in controls minus mean caries increment in the treated group divided by mean caries increment in controls. We conducted random‐effects meta‐analyses when data could be pooled. We assessed heterogeneity in the results of the studies by examining forest plots and by using formal tests for homogeneity. We recorded adverse effects (fluorosis) when the studies provided relevant data. MAIN RESULTS: We included 11 studies in the review involving 7196 children. In permanent teeth, when fluoride supplements were compared with no fluoride supplement (three studies), the use of fluoride supplements was associated with a 24% (95% confidence interval (CI) 16 to 33%) reduction in decayed, missing and filled surfaces (D(M)FS). The effect of fluoride supplements was unclear on deciduous or primary teeth. In one study, no caries‐inhibiting effect was observed on deciduous teeth while in another study, the use of fluoride supplements was associated with a substantial reduction in caries increment. When fluoride supplements were compared with topical fluorides or with other preventive measures, there was no differential effect on permanent or deciduous teeth. The review found limited information on the adverse effects associated with the use of fluoride supplements. AUTHORS' CONCLUSIONS: This review suggests that the use of fluoride supplements is associated with a reduction in caries increment when compared with no fluoride supplement in permanent teeth. The effect of fluoride supplements was unclear on deciduous teeth. When compared with the administration of topical fluorides, no differential effect was observed. We rated 10 trials as being at unclear risk of bias and one at high risk of bias, and therefore the trials provide weak evidence about the efficacy of fluoride supplements.

This investigation covers two technologies which have different applications but have many similar characteristics. One is the nanocell photoelectrochemical solar cell, the other is the electrochromic window

Systematic review conclusion There is no benefit to adding antivirals to corticosteroid therapy, versus using corticosteroids alone, in the treatment of Bell palsy. Critical summary assessment A meta-analysis of the data from six randomized controlled trials showed no difference between the two treatment modalities in terms of achieving at least partial facial muscle recovery in patients with Bell palsy. Evidence quality rating Limited

The technology of optical switching devices for dynamic glazings and other applications is discussed. The status of the state of the industry and its developments is detailed. The technical emphasis will be on the properties of chromogenic materials covering electrochromic, phase-dispersed liquid crystals and dispersed-particle systems. Such technologies can be used for dynamic control of solar energy through building and vehicle glazings. Both visible and solar control can be obtained from these devices. Switching ranges can be from as high as 80% to 5–10% transmittance in the visible region. The energy and daylighting benefits of such glazings are discussed. Also, chromogenic glazings can be used for other product applications such as the modulation of reflector surfaces and large electronic information display systems. The science of selected electrocchromic devices is covered. Technical issues concerning large-scale chromogenic devices are discussed.

Tungsten oxide and molybdenum doped tungsten oxide electrochromic films have been electrochemically prepared from a metal peroxide bath and experimentally tested. They were characterized by electrical and optical methods, using cyclic voltammograms and calculating the charge capacity as a function of the number of deposition cycles. The color of the electrochromic WO 3 film is strongly altered by doping it with molybdenum. Electrochromic W-Mo oxide films were fabricated by adding different percentages of molybdenum to tungsten oxide, ranging from 0.5% to 7% weight of deposition solution. Normal optical transmittance was also measured and evidence is given of different behavior of the switching for oxidation and reduction cycle, so that coloration occurs in a shorter time than the bleaching. The time constant of the process tends to increase as a function of the molybdenum oxide doping concentration.

Electron-beam-evaporated nickel oxide films were shown to have a microcrystalline cubic nickel oxide structure. The pressure in the chamber during the film deposition has a large effect on the crystal size and the stoichiometry of the films. The redox currents, the efficiency of these films to color, and their optical properties were influenced by the processing conditions employed and the resulting microstructure. A model is proposed based on the observed microstructure that explains the source of overstoichiometric oxygen and ion transport in these films.

An effort to transfer the technology of black chrome selective surfaces from the laboratories in industrial countries to a developing country has been carried out at King Mongkut's Institute of Technology Thonburi, Thailand. The first phase of the study is aimed at reproducing the findings obtained previously on the laboratory scale by others using the Harshaw (now Englehard Industries, Cleveland, OH, USA) Chromonyx TM process. The search for the optimum deposition conditions was performed employing a novel gradient search method. The radiative properties and the stability of the black chrome surfaces are reproducible. The second phase involved the subsequent development of these initial efforts into the larger scale of pilot plant production. A pilot scale black chrome plating unit has been designed and entirely constructed from technology indigenous to Thailand. The unit can electroplate black chrome on 1.5 × 10 dm 2 (10 dm = 1 m) aluminium substrates on a semicontinuous basis. The radiative properties of the coated surfaces averaged over the entire 15 dm 2 area are α s = 0.97 and ϵ t = 0.17. The uniformity of the plating indicated by the variation of the ϵ t values is good with reproducibility of ±0.015. Economic analysis of a plant designed to produce 17 300 m 2 per year gives a payback time of 3.5 years, assuming the economic conditions of Thailand in 1985. Our successful development of a pilot plant to manufacture black chrome is useful to other countries of comparable resources.

Thin films of hydrated manganese oxide were electrodeposited out of a base solution onto conductive SnO2: F glass. When cycled in a 1 M KOH solution, these films show the ability to reversibly store ions of dissociated water, however they show phase instability upon longer cycling. X-ray photoelectron spectroscopy was employed to investigate the chemical composition of the manganese oxide films. Our results indicate that hydrated MnO2 is the composition of the film in the oxidized state. Very low coloration was noted in these films making them useful for transparent counter-electrodes. As indicated by voltammetry, the switching voltage and ion-storage capacity fit the electrochromic switching of nickel oxide, undergoing a similar reaction. Because of its properties, manganese oxide, once stabilized, may serve as a counter-electrode for an electrochromic nickel oxide device.

A high-performance liquid chromatography procedure for the determination of selected non-steroidal anti-inflammatory analgesics (acetylsalicylic acid, fenbufen, fenoprofen, ibuprofen, indomethacin, ketoprofen, naproxen, sulindac and tolmetin) from pharmaceutical dosage forms has been developed. The individual analytes are extracted from the dosage forms with 0 to 10% aqueous acetonitrile and chromatographed on a 22-cm underivatized silica column at ambient temperature (23 ± 1°C). The mobile phases consisted of 5 mM aqueous sodium phosphate—phosphoric acid buffer, pH 2.6 containing 0 to 10% acetonitrile. Accuracy and precision of the method were shown to be excellent. This study was performed to extend the applicability of underivatized silica stationary support with aqueous eluents to the analysis of acidic compounds.

The retinoic acid molecule, a vitamin A derivative, is of key importance for eye and photoreceptor development in vertebrates. Several studies have provided evidence that the ventral part of the retina is particularly susceptible to impairment in retinoid signalling during the period of its development. In zebrafish, targeted gene knockdown of beta,beta-carotene-15,15`-oxygenase (bcox), the key enzyme for vitamin A formation, provokes a loss of retinoid signalling during early eye development that results in microphthalmia at larval stages. Using this model, we analysed the consequences of this for the retinal morphology of the fish larvae in structural details. Our analyses revealed that rods and cones do not express photoreceptor specific proteins (rhodopsin, peanut agglutinin, zpr1) in the peripheral retina. The photoreceptors in the central retina showed shortened outer segments, and electron dense debris in their intermembranal space. The number of phagosomes was increased, and cell death was frequently observed in the outer nuclear layer. Furthermore, the number of Muller cells was significantly reduced in the inner nuclear layer. Thus, we found that the lack of retinoid signalling strongly effects photoreceptor development in the ventral and dorsal retina. In addition, shortened outer segments and cell death of the remaining photoreceptors in the central retina indicate that there is an ongoing need for retinoid signalling for photoreceptor integrity and survival at later developmental stages.

Forward genetic screens have been instrumental in defining molecular components of visual function. The zebrafish mutant fading vision (fdv) has been identified in such a screen due to defects in vision accompanied by hypopigmentation in the retinal pigment epithelium (RPE) and body melanocytes. The RPE forms the outer most layer of the retina, and its function is essential for vision. In fdv mutant larvae, the outer segments of photoreceptors are strongly reduced in length or absent due to defects in RPE cells. Ultrastructural analysis of RPE cells reveals dramatic cellular changes such as an absence of microvilli and vesicular inclusions. The retinoid profile is altered as judged by biochemical analysis, arguing for a partial block in visual pigment regeneration. Surprisingly, homozygous fdv vision mutants survive to adulthood and show, despite a persistence of the hypopigmentation, a partial recovery of retinal morphology. By positional cloning and subsequent morpholino knock-down, we identified a mutation in the silver gene as the molecular defect underlying the fdv phenotype. The Silver protein is required for intralumenal fibril formation in melanosomes by amylogenic cleavage. Our data reveal an unexpected link between melanosome biogenesis and the visual system, undetectable in cell culture.

The egg yolk of vertebrates contains carotenoids, which account for its characteristic yellow color in some species. Such plant-derived compounds,e.g. β-carotene, serve as the natural precursors (provitamins) of vitamin A, which is indispensable for chordate development. As egg yolk also contains stored vitamin A, carotenoids have so far been solely discussed as pigments for the coloration of the offspring. Based on our recent molecular identification of the enzyme catalyzing provitamin A conversion to vitamin A,we address a possible role of provitamin A during zebrafish (Danio rerio) development. We cloned the zebrafish gene encoding the vitamin A-forming enzyme, a β,β-carotene-15,15′-oxygenase. Analysis of its mRNA expression revealed that it is under complex spatial and temporal control during development. Targeted gene knockdown using the morpholino antisense oligonucleotide technique indicated a vital role of the provitamin A-converting enzyme. Morpholino-injected embryos developed a morphological phenotype that included severe malformation of the eyes, the craniofacial skeleton and pectoral fins, as well as reduced pigmentation. Analyses of gene expression changes in the morphants revealed that distinct retinoic acid-dependent developmental processes are impaired, such as patterning of the hindbrain and differentiation of hindbrain neurons, differentiation of neural crest derivatives (including the craniofacial skeleton), and the establishment of the ventral retina. Our data provide strong evidence that, for several developmental processes, retinoic acid generation depends on local de novo formation of retinal from provitamin A via the carotene oxygenase, revealing an unexpected, essential role for carotenoids in embryonic development.

Beam emission spectroscopy (BES) system in Korea Superconducting Tokamak Advanced Research (KSTAR) has recently been upgraded. The background intensity was reduced from 30% to 2% by suppressing the stray lights. This allows acquisition of the relative electron density profiles on the plasma edge without background subtraction from the beam power modulation signals. The KSTAR BES system has its spatial resolution of 1 cm, the temporal resolution of 2 MHz, and a total 32 channel (8 radial × 4 poloidal) avalanche photo diode array. Most measurements were done on the plasma edge, r/a ∼ 0.9, with 8 cm radial measurement width that covers the pedestal range. High speed density profile measurements reveal temporal behaviors of fast transient events, such as the precursors of edge localized modes and the transitions between confinement modes. Low background level also allows analysis of the edge density fluctuation patterns with reduced background fluctuations. Propagation of the density structures can be investigated by comparing the phase delays between the spatially distributed channels.

Switchable windows can be used for a variety of applications including architectural and vehicle windows, aircraft transparencies, skylights and sunroofs. Related to glazing are applications for low-information content displays for the display of information. Switchable windows rely on a variety of processes and materials. Several companies throughout the world are developing dynamic glazing. University and National Laboratory groups are researching new materials and processes to improve these products. Switchable glazing for building and vehicle application is very attractive. Conventional glazing only offers fixed transmittance and control of energy passing through it. Given the wide range of illumination conditions and glare, a dynamic glazing with adjustable transmittance offers the best solution. This study covers selected switching technologies including, electrophoresis or suspended particles, electrochromism, liquid crystals, thermotropism and gaschromism. Currently much development in switchable devices is aimed at deposition processes suitable for glass substrates. In the future, there is movement towards plastic substrates for weight savings. Cost of production and defects in large-area deposition are two of the largest issues. These exciting technologies create many challenges and opportunities for glass and plastic companies along with excitement for building designers.

Presence of venous angioma (VA) in a close vicinity of cavernous angioma (CA) of the brain enhances the risk of bleeding from CA. However, VA drains the venous blood from surrounding brain tissue and should be left in place during surgical removal of CA. Coincidence of CA and VA was found in 6 of 44 patients operated on for 45 CA during a six years period (1993-1998). Coincidental VA were found more often with the CA located in the deep structures of the brain, in the thalamus and the brainstem (5 of 15 cases) than with the superficial CA (1 of 30 cases). The most valuable diagnostic method was T1 weighted MR imaging with contrast enhancement, less reliable was nonenhanced T1 or proton density weighted imaging. Finding of the VA may positively influence the decision making concerning the indication for surgery and the selection of the most appropriate surgical tactics. (Tab. 1, Fig. 2, Ref. 15.)

This work covers advances in large-area switchable glazing and flat panel displays. Large flat panels and glazing are being developed by a number of company and university groups. Certain novel flat panels display are made for electronic paper applications. Switchable glazing offers a new way of visualizing the function of a window. Switchable glazing can have a range of adjustable visible properties and shading coefficients. Technologies covered for glazing are electrochromism, suspended particles, encapsulated liquid crystals. Technologies being developed for electronic paper and certain flat display panels include electrophoretics, liquid crystals and bichromal balls. Beyond glazing applications, products based on this technology are flexible displays, electronic paper, switchable modulators, mirrors, and eyeglasses. This study covers developments from several companies including the one square meter electrochromic glazing made by Pilkington/Flabeg and Asahi/Nippon Mitsubishi Oil.

We report recent experimental results from HL-2A and KSTAR on ELM mitigation by supersonic molecular beam injection (SMBI). Cold particle deposition within the pedestal by SMBI is verified in both machines. The signatures of ELM mitigation by SMBI are an ELM frequency increase and ELM amplitude decrease. These persist for an SMBI influence time τI. Here, τI is the time for the SMBI influenced pedestal profile to refill. An increase in fELMSMBI/fELM0 and a decrease in the energy loss per ELM ΔWELM were achieved in both machines. Physical insight was gleaned from studies of density and vΦ (toroidal rotation velocity) evolution, particle flux and turbulence spectra, divertor heat load. The characteristic gradients of the pedestal density soften and a change in vΦ was observed during a τI time. The spectra of the edge particle flux Γ ∼ 〈ṽrñe〉 and density fluctuation with and without SMBI were measured in HL-2A and in KSTAR, respectively. A clear phenomenon observed is the decrease in divertor heat load during the τI time in HL-2A. Similar results are the profiles of saturation current density Jsat with and without SMBI in KSTAR. We note that τI/τp (particle confinement time) is close to ∼1, although there is a large difference in individual τI between the two machines. This suggests that τI is strongly related to particle-transport events. Experiments and analysis of a simple phenomenological model support the important conclusion that ELM mitigation by SMBI results from an increase in higher frequency fluctuations and transport events in the pedestal. © 2014 IAEA, Vienna.

This study covers advances in solar selective absorbers. The classes of selective absorbers are discussed along with their characteristics and physics. From much of the research and development on solar coatings in the 1970s and early 1980s only black chrome and nickel-pigmented aluminum have been largely commercially adopted. Black chrome still has the best proven overall operational characteristics for the higher flat plate collector temperatures. New types of coatings are being developed by vacuum and chemical deposition processes. Some coatings are being developed for increased temperature applications. The new coatings are known as 'black crystal,' a dendritic black nickel, TiNxOy, and sputtered black nickel. These coatings are emerging in the marketplace, but long-term testing has not been performed yet. The characteristics of these coatings are discussed. Several issues concerning coating and process ecology are also discussed.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The developing field of switchable chromogenic materials for smart windows and other large-area applications is discussed. A selection of switchable glazing devices that change color electrically are detailed. The types of devices covered are the electrochromic which color electronically, covering electrochromic, dispersed liquid crystal and dispersed particle glazing that switch under an applied electric field. Device structures and switching characteristics are compared. The status of prototype and commercial devices from commercial and university labs through out the world are covered. A discussion of the future of this technology is made including areas of necessary development for the realization of large area glazing in excess of 1 m2.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The optical and electrochemical properties of sol-gel spin coated CeO2-TiO2 (50% CeO2) films were investigated for electrochromic applications. The coating solutions were prepared by using mixed organic-inorganic [Ti(OC2H5)4 and Ce(NH4)2 (NO3)6] precursors. X-ray diffraction studies showed the sol-gel spin- coated films were composed of an amorphous matrix of titanium oxide containing nanocrystallites of cerium oxide. The coating solar transmission value was Ts equals 0.8 (250 nm thick). The refractive index and the extinction coefficient were derived from transmittance measurements in the UV-VIS-NIR regions. These films had refractive index value of n equals 2.18 and extinction coefficient value of k equals 8 X 10-4 at (lambda) equals 550 nm. Cyclic voltametric measurements showed reversible electrochemical insertion of lithium ions in a CeO2-TiO2/LiClO4-propylene carbonate electrochemical cell. During cycling the films maintain high optical transmittance. Spectrophotometric and electrochemical investigations performed on CeO2-TiO2 films revealed that these films are suitable as an optically passive counter-electrode in lithium electrochromic devices.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Electrochromic devices have increasing application in display devices, switchable mirrors and smart windows. A variety of vacuum deposition technologies have been used to make electrochromic devices. The sol-gel process offers an alternative approach to the synthesis of optical quality and low cost electrochromic device layers. This study summarizes the developments in sol-gel deposited electrochromic films. The sol-gel process involves the formation of oxide networks upon hydrolysis-condensation of alkoxide precursors. In this study we cover the sol-gel deposited oxides of WO3, V2O5, TiO2, Nb2O5, and NiOx.

A beam emission spectroscopy (BES) system based on direct imaging avalanche photodiode (APD) camera has been designed for Korea Superconducting Tokamak Advanced Research (KSTAR) and a trial system has been constructed and installed for evaluating feasibility of the design. The system contains two cameras, one is an APD camera for BES measurement and another is a fast visible camera for position calibration. Two pneumatically actuated mirrors were positioned at front and rear of lens optics. The front mirror can switch the measurement between edge and core region of plasma and the rear mirror can switch between the APD and the visible camera. All systems worked properly and the measured photon flux was reasonable as expected from the simulation. While the measurement data from the trial system were limited, it revealed some interesting characteristics of KSTAR plasma suggesting future research works with fully installed BES system. The analysis result and the development plan will be presented in this paper.

Tantalum oxide films were prepared by sol-gel process using tantalum ethoxide Ta(OC2H5)5. The dependence of deposition conditions (i.e. composition of polymeric solutions and spinning rate) on ionic conductivities for tantalum oxide films were studied. The best results achieved for films fabricated by the spin coating technique from clear polymeric solutions. These films had low packing density (rho) equals 3.2 g/cm3 and good proton conductivity (about 10-6 (Omega) -1/cm-1). X-ray photoelectron spectroscopy (XPS) was used for studying the compositions of the tantalum oxide films. We report on the use of tantalum oxide films as ion conductors in devices consisting of WO3/Ta2O5/H+ ion storage polymer structure. We found tantalum oxide to have very good properties for proton device applications.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The use of polyorganodisulfides as optically passive counter-electrodes in a variety of electrochromic devices are discussed. Characteristic data is presented for electrochromic devices using proton, and lithium coloration ions with polyethylene oxide electrolyte and polydimercaptothiadiazole positive electrodes. Solid state devices consisting of molybdenum doped WO3, emorphous polyethylene oxide electrolyte (a-PEO), and a polyorganodisulfide counter-electrode colored rapidly from a pale yellow to a deep blue-green, upon application of 1.2 V d.c. The photopic transmittance changed from 61 to 9%, and the solar transmittance from 45 to 5% during the coloration process. Also, our experiments with polyimidazole are detailed. This family of compounds due to its unique electrical and ion conduction properties allow a single composite ion storage and ion conductor electrode to be made, simplifying the device construction. Devices made from this family of compounds color to deep blue-gray upon application of 1.2 - 1.5 V. Bleaching occurs at -0.4 to -0.5V. The photopic transmittance changed from 55 to 9%, and the solar transmittance from 34 to 4% during coloration. Both coloration and bleaching are quite rapid.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

We report on the fabrication and use of new ion storage layers as counter electrodes for completely solid state electrochromic windows. The ion storage layers are transparent composites of a room temperature ion-conducting polymer and an electroactive material based upon the polyorganodisulfide/dithiolate redox couple. Solid state devices consisting of molybdenum doped W0 3 , a polymer ion conductor layer and the new ion storage layers colored rapidly from a pale yellow to a deep blue-green, upon application of 1 .2 V d.c. The photopic transmittance changed from 6 1 to 9% , and the solar transmittance from 45 to 5% during the coloration process, for a typical example. Because the counter electrode does not change optical properties as a function of redox state, problems with color imbalance can be avoided completely. The large number of polyorganodisulfides that may be used for this application allows for flexibility in device design and properties, and the use of solid state components ensures improved stability of windows incorporating this technology.

This paper reports on the preparation, electrical, and optical analysis of electrodes and prototype electrochromic devices using a solid polymer ion conductor. For these devices electrodes were developed consisting of cobalt-doped nickel oxide, manganese-nickel oxide, and niobium oxide. Optical and voltammetric data was obtained for each electrode. Solid polymer electrolytes were synthesized from modified amorphous poly(ethylene oxide) [a-PEO] complexed with a metal silicate. Electrochromic devices were made using cobalt-doped nickel oxide/niobium oxide, and cobalt-doped nickel oxide/manganese-nickel electrode laminations. Optical spectra as a function of voltage was obtained for each device. The best cobalt-doped nickel oxide/a-PEO/manganese-nickel oxide device showed photopic transmittance to be Tp(bleached) equals 0.76 and Tp(colored) equals 0.44. The corresponding integrated solar transmittance was Ts(bleached) equals 0.64, Ts(colored) equals 0.46. The best cobalt- doped nickel oxide/a-PEO/niobium oxide device had photopic transmittance of Tp(bleached) equals 0.65 and Tp(colored) equals 0.16. The corresponding integrated solar transmittance was Ts(bleached) equals 0.45 and Ts(colored) equals 0.15. Of the two devices, the nickel/niobium oxide device had the best combination of electrical and optical properties. Better device properties are expected with improvements in the solid polymer electrolyte and lamination process.

Electrochromic device testing and durability is discussed in this study. This work begins with a discussion of performance criteria for switchable glazings used in building applications. This is followed by device design of several common electrochromic device types. The types are distinguished by structure and electrolyte type. A number of test methods are used for the analysis of electrochromic devices. Device lifetime and degradation covers considerable work on amorphous tungsten oxide. Some degradation and ageing modes are identified for electrochromic devices during static and cyclic testing. The degradation modes are film dissolution, transparent conductor etching, gas generation, humidity dependence, secondary reactions and photoreactions. Many of these mechanisms are specific to the materials, device design, and the operating conditions used. Overall, future of electrochromic devices looks very promising, but there are many issues in this study that designers need to take into consideration for electrochromic glazings.

Over the last few years, hydrated nickel oxide or hydroxide has gained interest as an electrochromic materiall. It has many important features. First it shows a transparent to bronze coloration which is suitable for a number of architectural, vehicle and aerospace glazing applications. This material is stable in an alkaline environment and colors and bleaches at potentials below 1.0V and below the oxygen and hydrogen evolution potentials. It can be deposited by a wide range of processes, including anodic and cathodic electrodeposition, r.f. and d.c. sputtering, vacuum evaporation, chemical vapor deposition, and solgel processes. In this work we will discuss films made chiefly by anodic electrodeposition. Some of the best characteristics are seen in films made by electrodeposition. The properties of films made by other deposition processes will be discussed in subsequent chapters. Much of the electrochemical knowledge about hydrated nickel oxide comes from studies of metallic nickel electrodes used in batteries. The study of hydrated nickel oxide based electrochromic devices is just emerging, and so far very few devices have been reported2-4. Some of the work by my group on nickel based devices will be outlined later in this chapter.

This book deals with chromogenic materials and their uses primarily in large-area optical technology. The word "chromogenic" is new and is used here to denote materials which are able to alter their optical properties in response to a change in ambient conditions such as illumination intensity, temperature, applied electric field, etc. The changeable optical properties embrace transmittance, reflectance, absorptance and emittance.

The present state and performance of relatively large area transmissive electrochromic devices were reviewed. The largest size prepared has an electrode distance of about 60 cm. The response speed was shown to be limited mainly by the resistance of the transparent conductive coating, though the sheet resistivity available now is fairly low, around 10 {Omega}/sq. The rate of the process in the transmissive device will change from transparent electrode limited to electrolyte limited if the sheet resistivity could be lowered down to less than 1 {Omega}/sq. The present stat of large area transmissive EC devices is summarized. More investigation is necessary for a more accurate understanding of the physical and chemical properties of WO{sub 3} films, especially to provide countermeasures to degradation so that better device performance can be accomplished.