Charge transfer resistance of spray deposited and compressed counter electrodes for dye-sensitized nanoparticle solar cells on plastic substrates

Electrochemical impedance spectroscopy was used to determine the effective charge transfer resistances of porous dye-sensitized solar cell counter electrodes prepared by low-temperature spray deposition and compression of conductive carbon and platinized Sb-doped SnO₂ powders on indium tin oxide-coated plastic substrates. The charge transfer resistances were 0.5–2 and 8–13 Ω cm², respectively, when using 3-methoxypropionitrile as the electrolyte solvent. The manufacturing method used lends itself to produce mechanically stable and even-quality electrodes in an easy and fast manner.     

Copper and zinc metabolism in aspartylglycosaminuria and Salla disease

Changes in the metabolism of copper and zinc are described in aspartylglycosaminuria (AGU) patients. AGU patients had significantly reduced serum zinc concentrations. However, hair zinc levels were normal, and hyperzincuria could not be demonstrated. The copper content in the hair of AGU patients was highly elevated. Serum copper and ceruloplasmin concentrations were within normal range. In AGU, small-molecular-weight glycoasparagine storage products accumulate in tissues and are excreted in urine in large amounts. They may interfere with the transport mechanisms of trace elements, and thus alter their distribution and availability for tissues. The changes in copper and zinc levels may contribute to the pathogenesis of some of the clinical signs of AGU and Salla disease.     

Tele-Existence Techniques of Heavy Work Vehicles

The problem of finding a feasible and technically simple tele-existence system for teleoperation of heavy work vehicles is considered with the aid of two experimental test series. Several test persons of different ages and experience were used in experiments in which a basic audio/video tele-existence system with head-tracking was modified into different versions and tested. Conclusions indicate that details of the tasks and work environment have an important role in finding the optimal solution.     

Insights into corrosion in dye solar cells

The main issue in using low cost metals in dye solar cells is the corrosion caused by the liquid electrolyte. Contrary to typical applications of metals, the adverse effects of corrosion in dye solar cells are related to irreversible depletion of charge carriers from the electrolyte rather than consumption of the metal itself. It is calculated that the penetration rate due to corrosion should not exceed 10⁻⁴ mpy (a couple of nanometers per year) to ensure device lifetime longer than 1 year. This is 10 000 times slower rate than what is considered to be a general benchmark value for very low corrosion rate in the field of corrosion science and has a major effect on how corrosion should be investigated in the case of dye solar cells. Different methods, their applicability, and limitations to investigate corrosion in dye solar cells are evaluated here. The issue with most techniques is that they can detect metals that are clearly corroding, but they have significant limitations in proving a metal stable. Our investigation shows that the most reliable information on corrosion is obtained from complete dye solar cells that are exposed to working conditions. A combination of color analysis of the electrolyte to such measurement is proposed as a means to extrapolate future performance of the cells and estimate potential lifetimes of the dye solar cells in regards to corrosion. Copyright © 2014 John Wiley & Sons, Ltd.     

Oral findings in patients with active or inactive Crohn''s disease

The frequency and type of oral mucosal lesions, dental infections, and salivary constituents were evaluated in 53 patients with Crohn's disease, who were divided into inactive, mildly active, and severely active groups on the basis of clinical and endoscopic criteria. Buccal biopsies from nine patients with active disease showed morphologic changes that suggested Crohn's disease-related lesions. Panoramic radiographs revealed more infectious foci in the teeth of patients with active Crohn's disease than in patients with inactive disease. Salivary flow rate, buffering capacity, total protein, amylase, and IgA and IgG concentrations did not differ with respect to the activity of Crohn's disease. The observed mucosal inflammation in patients with active Crohn's disease, although high in frequency, was mild and did not need therapy, but the great number of dental infections in association with the activity of Crohn's disease should be taken into account in the treatment of these patients.     

Effect of source near- and far-field variations on the accuracy of multimode fibre attenuation measurements

The error incurred in fibre attenuation measurements due to variations in the launch near- and far-fields is examined for a statistically uniform near field and a cosp ? far field. It is found that even under well controlled conditions, spatial and wavelength variations could easily lead to interlaboratory errors in excess of ± 0.03 dB.     

Technique for reducing spatial and wavelength variations of launch spot in fibre attenuation measurements

A launching technique based on the use of a large step-index rod with a ground end face is described. Experimental results indicate a significant reduction in spatial and wavelength variations. Based on theoretical considerations, the resultant attenuation error in interlaboratory experiments is estimated to be about ± 0.03 dB.     

Optimal excitation of multimode graded-index fibres in d.m.d. and d.m.a. measurements

A wave optics computational procedure to obtain optimally selective excitation in d.m.d. and d.m.a. measurements is presented. Good agreement with a Fourier optics approach is found. It is shown that for the optimal excitation of higher order mode groups (by increasing input beam offset) the beam spot size must be considerably reduced from that for the optimal excitation of the fundamental mode.     

用背反射提高染料敏化太阳能电池光电转换效率的研究

当光射入染料敏化太阳能电池(DSCs)时,有部分光不能被染料、电解液、导电玻璃等吸收,这部分光将透过电池而未被利用,本研究利用普通镀铝玻璃镜做为背底,将这部分透射光通过背反射重新射入电池来提高DSCs的光电转换效率.研究结果表明,背反射能大幅度提高DSCs的短路电流,短路电流的增加率随着测试遮光罩开孔尺寸的增加而增加,并且随纳米TiO2薄膜厚度的增加而降低.