Gelatinisation of starch and wheat flour starch—A review

Gelatinisation of wheat starch is reviewed, making comparisons with other starches.Starch in wheat kernel endosperm is briefly described. Various aspects of gelatinisation of starch in water are considered, including swelling and interaction with water before the onset of gelatinisation, increase in consistency during gelatinisation, gelatinisation temperature, types of gelatinised system and gel and paste formation upon cooling. In addition, the traditional rationale of gelatinisation and gelatinisation from the viewpoint of water mobility are discussed.Experimental methods used to study gelatinisation are also reviewed, as are the effects of starch concentration, protein, pentosans, surface active agents, fats, salt and sugars on gelatinisation and shear rate on consistency.     

Bilinear finite elements for shells: Isoparametric quadrilaterals

We study the accuracy and reliability of the lowest‐order bilinear shell finite element schemes. Our approach is based mainly on a simplified shallow shell model analogous to the Reissner–Mindlin model of plate bending. The numerical models are constructed by modifying the strain expressions within the usual energy principle so that error analysis in the energy norm framework is possible. Our theoretical predictions supported by numerical experiments indicate that the performance of the low‐order methods is both mesh and case dependent. Copyright © 2007 John Wiley & Sons, Ltd.     

Effect of apartment building energy renovation on hourly power demand

ABSTRACT

Optimal energy renovations of apartment buildings in Finland have a great impact on annual energy demand. However, reduction of energy demand does not necessarily translate into similar changes in peak power demand. Four different types of apartment buildings, representing the Finnish apartment building stock, were examined after optimal energy retrofits to see the influence of retrofitting on hourly power demand. Switching from district heating to ground-source heat pumps reduced emissions significantly under current energy mix. However, the use of ground-source heat pumps increased hourly peak electricity demand by 46–153%, compared to district heated apartment buildings. The corresponding increase in electrical energy demand was 30–108% in the peak month of January. This could increase the use of high emission peak power plants and negate some of the emission benefits. Solar thermal collectors and heat recovery systems could reduce purchased heating energy to zero in summer. Solar electricity could reduce median power demand in summer, but had only a little effect on peak power demand. The reduction in peak power demand after energy retrofits was less than the reduction in energy demand.     

Effects of physical activity on the deposition of traffic-related particles into the human lungs in silico

Traffic-related particle emissions have been a great concern over a number of years due to their adverse health effects. In this research project, traffic-related particle deposition in the human lungs is studied using lung deposition estimates based on the ICRP 66 model. This study covers four human groups, i.e. adult males, adult females and two groups of children aged 5 and 10 years. The study examines particle deposition in the human lungs in relation to four different physical exercise levels, i.e. sleeping, sitting, light exercise and heavy exercise. To conduct the study, the particle size distributions of diesel and compressed natural gas (CNG) busses were monitored in field laboratory conditions. The study indicates that the total number of diesel particles measured is greater than the total number of CNG particles. The results further display that most of the diesel particles measured are smaller than 0.2 μm, whereas the CNG particles are smaller than 0.05 μm in aerodynamic diameter. The level of physical exercise, as well as the age and gender of a person affects the deposition of particles in the lungs. An increase in the physical activity results in larger amounts of small-size particles penetrating deeper into the respiratory system. The lung deposition of particles in males was substantially different compared to that of females and children. The deposited dose of particles was generally lower for females than for males and further lower for children than for females. This article argues that these groups should be discussed separately when conducting exposure assessments and that the level of physical activity should be taken into account when assessing potential health consequences.     

Bulk and surface mechanical properties of clay modified HDPE used in liner applications

High‐density polyethylene (HDPE)/clay nanocomposites were prepared by melt blending process. The HDPE was mixed with different organoclays and polyethylene‐grafted‐maleic anhydride was used as a compatibiliser. A masterbatch procedure was used to obtain final organoclays concentrations of 1, 2.5 and 5 wt%. The effects of various types of nanoclays and their concentrations on morphological, thermal and mechanical properties of nanocomposites were investigated. Surface mechanical properties such as instrumented nanohardness, modulus of elasticity and creep were also measured using a nanoindentation technique. Young's, storage and loss moduli, were found to be higher than that of the neat polymer at low loading (2.5 wt%) for clay Cloisite 15A and at higher loading (5 wt%) for clay Nanomer 1.44P. The ultimate strength and the toughness decreased slightly compared to pure HDPE. The differential scanning calorimetry analysis revealed that the peak temperature of the nanocomposites increased with increased clay content while the crystallinity decreased. Also, dynamic mechanical analysis revealed the storage and loss moduli are enhanced by addition of nanoclay. Both mechanical and thermal properties of HDPE/Nanomer 1.44P nanocomposite showed interesting trends. All properties first dropped when 1 wt% of the clay was added. Thereafter, a gradual increase or decrease then followed as the loading of Nanomer was increased. These trends were observed for all mechanical properties. The results obtained from nanoindentation tests for surface mechanical properties also showed similar trend to that of bulk measurements. Based on these measurements a nanoclay additive for a liner grade HDPE was selected. © 2011 Canadian Society for Chemical Engineering     

Newness,Tradition and Identity: Existential Content and Meaning in Architecture

At a time when novelty and aesthetic invention have become the established norm for contemporary architecture, the esteemed Finnish author and architect Juhani Pallasmaa speaks out in defence of tradition. He explains how nuance, expressive subtlety and an ambition for an experiential and existential quality in a work require a sense of historical continuum: ‘An embodiment of the essence of tradition’ as a precursor for ‘meaningful creativity’.     

Temperature optimisation of a diesel engine using exhaust gas heat recovery and thermal energy storage (diesel engine with thermal energy storage)

Modern automotive diesel engines are so energy efficient that they are heating up slowly and tend to run rather cold at subzero temperatures. The problem is especially severe in mail delivery operations where the average speed is low and the drive cycle includes plenty of idling. The problem is typically solved by adding a diesel fuelled additional engine heater which is used for the preheating of the engine during cold start and additional heating of the engine if the coolant temperature falls below a thermostat set point during the drive cycle. However, this additional heater may drastically increase the total fuel consumption and exhaust gas emissions of the vehicle. In this study the additional heater was replaced by a combination of exhaust gas heat recovery system and latent heat accumulator for thermal energy storage. The system was evaluated on a laboratory dynamometer using a simulated drive cycle and in field testing in the city of Oulu (65°N), Finland in February 2009.     

Hapticity Vision

The Eyes of the Skin has become an architectural classic. Here, on the publication of a new edition, its author Juhani Pallasmaa reflects on why a sensory understanding of the world has grown in an increasingly digital age. Copyright © 2005 John Wiley & Sons, Ltd.     

The Ehrenfeucht conjecture: a compactness claim for finitely generated free monoids

We survey recent results on the so-called Ehrenfeucht Conjecture which states: For each language L over a finite alphabet Σ there exists a finite subset F of L such that for each pair (g, h) of morphisms on Σ¹ the equation g(x)=h(x) holds for all x in L if and only if holds for all x in F.We point out that the conjecture is closely related to the theory of equations in free monoids. We also state a suprising consequence of the conjecture: If it holds (even noneffectively) for all DOL languages, then the HDOL sequence equivalence problem is decidable. Furthermore, we give examples of when the conjecture is known to hold. In particular, we establish it for all binary languages, as well as for all languages when attention is restricted to bounded delay morphisms of some fixed delay.     

Inverse morphic equivalence on languages

We introduce the notion of inverse morphic equivalence of two morphisms g and h on a language L. Two variants are considered, the universal version, that is h^-1(x)=g^-1(x), for all x in L, and the existential version, that is h^-1(x)∩g^-1(x)≠Ø, for all x in L with h^-1(x)∪g^-1(x)≠Ø.