Facade systems with variable solar control using thermotropic polymer blends

Thermotropic layers integrated into glazing or transparent insulation systems reversibly reduce the total solar energy transmittance by becoming opaque when heated. Characteristics of both systems have been measured as a function of temperature and incidence angle, including the total solar energy transmittance for a thermotropic heat-mirror insulating glazing unit (IGU). Properties of complex thermotropic glazing systems have been simulated, starting from data characterising the thermotropic layer. The results show good agreement with measured data. A prototype system sample of a thermotropic heat-mirror IGU was integrated into an outdoor test facility and a thermotropic TEIF (transparent exterior insulation and finish) prototype system was installed into the facade of a demonstration house. Both systems have been monitored and showed the expected switching properties, resulting in the desired overheating protection. Computer simulations of the building integration of the thermotropic TEIF system have been performed, showing a strong dependence of the optimum switching temperature on the total solar and internal gains of the building.     

The effect of metal ion content on the viscosity of gum ghatti

Cold water extraction of gum ghatti gives a soluble gum and an insoluble gel. The two fractions were shown by potentiometric titration to have the same acid equivalent weight and to be largely in the salt form, with less than 10% in the free acid form. Quantitative analysis of the two fractions for metal ion content showed that the gel fraction was largely a calcium salt. The soluble fraction contains calcium, potassium, sodium, and magnesium. Precipitation of the calcium ions reduces the viscosity but the original viscosity is not restored by addition of calcium ions.     

The herpesvirus protease: mechanistic studies and discovery of inhibitors of the human cytomegalovirus protease

This paper is a review of the literature on the possible association between osteoporosis and oral bone loss, with an emphasis on radiological studies. Such an association was first suggested in 1960. Subsequent histomorphometric and microradiographic studies showed that after the age of 50 there was a marked increase in the cortical porosity of the mandible, with this increase being greater in the alveolar bone than the mandibular body; and that with this increase in porosity, there was a concomitant decrease in bone mass, which appeared to be more pronounced in females than in males, with the loss in bone mineral content estimated to be 1.5% per year in females and 0.9% in males. These studies also demonstrated a considerable amount of variation in the amounts of cortical and trabecular bone within and among individuals. Subsequent clinical studies reported associations between the bone densities of jaws and (1) metacarpals, (2) forearm bones, (3) vertebrae and (4) femurs. These studies indicated that women had lower mandibular bone mineral content (BMC) than men and that age-related loss of bone was more pronounced in women after the age of 50 years than in men of the same age, as was the case for the rest of the body. It was suggested that systemic factors responsible for osteoporotic bone loss may combine with local factors (periodontal diseases) to increase rates of periodontal alveolar bone loss. Although not all studies found associations between osteoporosis and oral bone loss, the conclusion of this review is that such an association exists; yet additional longitudinal investigations are needed to confirm this, and before the implications of this association could be fully utilized in clinical dentistry, inexpensive methods must be developed for sensitive and specific measures of oral bone loss.     

The dependence of the chemical potential of WO3 films on hydrogen insertion

Knowledge of the chemical potential of electrochromic films coloured by hydrogen is important for matching the elements of an electrochromic device, for understanding the colouring mechanism and for obtaining information about the microscopic structure of the film. The dependence of the chemical potential on the hydrogen concentration was measured electrochemically for tungsten oxide films of different crystallinity and water content. A new method for determining the chemical potential by catalytic coloration by hydrogen gas is introduced. It revealed that the increase in electromotive force with increasing crystallinity is due only to different binding energies of the protons. We expect the protons to be located in the centres of hexagons, which are created by WO₆ octahedra. According to our model, amorphous sputtered films show a hexagonal structure which is similar to that of evaporated films, but the hexagons are connected, leading to more hexagon centre sites, which increases the electromotive force.     

Cross-modal illusory conjunctions between vision and touch.

Cross-modal illusory conjunctions (ICs) happen when, under conditions of divided attention, felt textures are reported as being seen or vice versa. Experiments provided evidence for these errors, demonstrated that ICs are more frequent if tactile and visual stimuli are in the same hemispace, and showed that ICs still occur under forced-choice conditions but do not occur when attention to the felt texture is increased. Cross-modal ICs were also found in a patient with parietal damage even with relatively long presentations of visual stimuli. The data are consistent with there being cross-modal integration of sensory information, with the modality of origin sometimes being misattributed when attention is constrained. The empirical conclusions from the experiments are supported by formal models. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Radiation filters and emitters for the NIR based on periodically structured metal surfaces

Abstract

The spectrally selective optical properties of wavelength selective radiation emitters and filters based on periodically microstructured metal surfaces were investigated. Metal surfaces were structured by the use of a holographic mask and subsequent etching processes. Due to the microstructure, thermally excited surface plasmons couple to electromagnetic radiation. Therefore a structured tungsten surface can act as a selective radiation emitter. The calculation of the absorptance by a rigorous diffraction theory allows the prediction of the emissivity of such structures. The angle dependent emissivity of tungsten gratings with periods of 1.4 μm and 2.0 μm was measured. A peak emissivity of 70% at a wavelength of 1.6 μm was achieved. Band pass filters for the near infrared spectral range based on perforated metal films were investigated theoretically and experimentally. Filters with a grating period of 2.0 μm were produced. A peak transmittance of 80% at a wavelength 2.9 μm was achieved. The optical properties of the diffractive elements described partly show a strong angle dependence     

From a library of MAG antagonists to nanomolar CD22 ligands

Siglec-2, also known as CD22, is involved in the regulation and survival of B-cells and has been successfully targeted in cell depletion therapies with antibody-based approaches. Sialic acid derivatives, already known to bind with high affinity to myelin-associated glycoprotein (MAG, Siglec-4), were screened for their binding affinity for CD22 by surface plasmon resonance. The best compound identified was further modified with various hydrophobic substituents at the 2-, 5-, and 9-positions of the sialic acid scaffold, leading to nanomolar derivatives, of which ligand 17 b shows the most promising pharmacodynamic and pharmacokinetic profiles. Isothermal titration calorimetry measurements demonstrate that the binding is enthalpy driven. Interestingly, the thermodynamic fingerprints reveal an excellent correlation between gains in enthalpy and compensation by increased entropy costs. Moreover, 17 b exhibits a residence time in the range of a few seconds, clearly prolonged relative to residence times typically observed for carbohydrate-lectin interactions. Finally, initial tests regarding drug-like properties of 17 b demonstrate the required high plasma protein binding yet a lack of oral availability, although its distribution coefficient (log D) is in the required range.     

Methodology of Single Crystal Growth and Microstructure Analysis of CoTi(Zr) Intermetallic Compounds

1. IntroductionThe strong bonding between different atoms in inter-metallic compounds often results in attractive properties,such as strength retention at high temperature. A posi-tive temperature dependence of yield stress in some com-pounds such like Ni3Al, CuZr, FeCo and Fe3Al was dis-covered at an early stage. Now many other compoundshave been found to show this peculiar mechanical be-haviour, which can be useful in high temperature struc-ture applications.Ordered B2-type intermetallic…