Comparison of energy conservation building codes of Iran,Turkey, Germany,China, ISO 9164 and EN 832

To improve the energy efficiency of buildings via compliance to regulation in Iran, Code No. 19 was devised in 1991. The code lacks high level aims and objectives, addressing the characteristics of Iranian buildings. As a consequence, the code has been revised and is not completely implemented in practice, and still remains inefficient. As with any energy coding system, this code has to identify the right balance between the different energy variables for the Iranian climate and way of life. In order to assist improvements to high level objectives of Code 19, this code is compared with ISO 9164, EN 832, German regulation, TS 825 of Turkey and China’s GB 50189 to understand how these have adapted international standards to national features. In order to test the appropriateness of Code 19, five case study buildings in Iran are assessed against Code 19 as well as Turkish standard TS 825 and the results are compared. The results demonstrate that Code 19 is efficient in calculations of building envelope, but it needs improvements in the areas of ventilation, gains from internal and solar sources. The paper concludes by offering suggestions for improving the code.     

Pathways to a hydrogen fuel infrastructure in Norway

Hydrogen is expected to become an integral part of the Norwegian energy system in the future, primarily as transportation fuel. The NorWays project aims at providing decision support for introduction of hydrogen in the Norwegian energy system by modelling of energy system and hydrogen infrastructure at various spatial levels. GIS-based regional hydrogen demand scenarios and fuelling station networks have been generated, considering organic growth of regional hydrogen coverage and increasing density of hydrogen users over time. A regional model optimised supply scenarios for these fuelling station networks, including choice of production technology (biomass gasification, NG SMR, electrolysis, by-product hydrogen) and delivery (pipeline, truck, and onsite schemes), including integrated hydrogen delivery networks by truck and pipeline. The impact of energy price and GHG emission constraint scenarios on hydrogen production and delivery mix and average hydrogen costs is analysed, and conclusions on the effectiveness of policy measures are drawn.     

Studies on steam condensation and particle diffusiophoresis in a heat exhanger tube

In this paper, studies on steam condensation and aerosol behaviour in a heat exchanger are presented. The heat exchanger is a model of one single tube of a Passive Containment Condenser (PCC) that is used in the European Simplified Boiling Water Reactor (ESBWR). A hot carrier gas containing nitrogen and steam with Ag and CsOH particles flows through the heat exchanger. The walls of the heat exchanger are cooled with a water jacket, thus causing steam condensation and diffusiophoretic particle deposition. The amount of condensed steam is measured, as well as the temperatures, particle mass concentrations and size distributions before and after the heat exchanger. The experiments are done with different proportions of steam and nitrogen in the carrier gas. Heat and mass transfer in the system are modelled with well known engineering correlations, producing results that agree nicely with the experimental results. The diffusiophoretic particle deposition velocity is shown to be proportional to the steam condensation rate, as expected.     

Electrostatic precipitator performance and trace element emissions from two Kraft recovery boilers

Fine particle emissions from combustion sources have gained attention recently due to their adverse effects on human health. The emission depends on the combustion process, fuel, and particulate removal technology. Particle concentrations at Kraft recovery boiler exits are very high, and the boilers are typically equipped with electrostatic precipitators (ESP). However, little data are available on the ESP performance in recovery boilers. Particle concentrations and size distributions were determined at two modern, operating recovery boilers. In addition, we determined the fractional collection efficiency of the ESPs by simultaneous measurements at the ESP inlet and outlet and the particulate emissions of trace metals. The particle mass concentration atthe ESP inlet was 11-24 g/Nm3 at the two boilers. Particle emissions were 30-40 mg/ Nm3 at boiler A and 12-15 mg/Nm3 at boiler B. The particle size distributions had a major particle mode at around 1 microm. These fume particles contained most of the particle mass. The main components in the particles were sodium and sulfate with minor amounts of chloride, potassium, and presumably some carbonate. The ESP collection efficiency was 99.6-99.8% at boiler A and 99.9% at boiler B. The particle penetration through the ESP was below 0.6% in the entire fume particle size range of 0.3-3 microm. Trace element emissions from both boilers were well below the limit values set by EU directive for waste incineration.     

Associations between persistent organic pollutants and vitamin status in Brünnich's guillemot and common eider hatchlings

The aim of the study was to examine associations between persistent organic pollutants and vitamin A (retinol), retinyl palmitate and vitamin E status (alpha-tocopherol) in two species occupying different trophic positions in the Arctic food web. Levels of polychlorinated biphenyls (PCBs), some selected organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCD) were analyzed in yolk sac of newly hatched chicks of Brünnich's guillemot (Uria lomvia) and common eider (Somateria mollissima) from Kongsfjorden, Svalbard (Norwegian Arctic) (79 degrees N). Morphological variables were measured, and levels of retinol, retinyl palmitate and alpha-tocopherol were analyzed in plasma and liver. Brünnich's guillemot had significantly higher levels of POPs than common eider, as expected from its higher trophic position. Morphological traits seemed to be negatively related to POPs in Brünnich's guillemots, but not in common eiders. In Brünnich's guillemot, negative relationships were found between some OCPs (hexachlorobenzene, oxychlordane, p,p'-DDE) and liver alpha-tocopherol levels. The negative relationships between these OCPs and liver alpha-tocopherol levels in Brünnich's guillemot hatchlings became less evident when the confounding effect of liver mass was corrected for. In common eider positive relationships were found between summed PCB (SigmaPCBs) and some OCPs (beta-hexachlorocyclohexane, oxychlordane) and liver alpha-tocopherol levels. Differences in relationships between POPs and vitamin status in the two species may be related to differences in POP exposure levels linked to their trophic position in the Arctic marine food web, or to intrinsic physiological differences between the species.     

Low-Voltage CMOS Rail-to-Rail V-I Converters

This paper presents two CMOS low-voltage rail-to-rail voltage-to-current converters (V-I converter) which could be used as basic building blocks to construct low-voltage current-mode analog VLSI circuits. In each of the circuits, an N-type V-I converter cell is connected in parallel with its P-type counterpart to achieve common-mode rail-to-rail operation. A linear differential relationship of the N-type V-I converter, or its P-type complement, is obtained using a new class-AB linearization technique. In the first rail-to-rail V-I converter circuit, a constant transconductance is achieved through the use of two maximum-current selecting circuits and an output subtraction stage. In the second circuit, a constant transconductance value is obtained by manipulating the DC bias currents of N- and P-type V-I converter cells. Both of the circuits can operate from rail to rail with a power supply of 3V, or less depending on the VLSI technology and the DC bias current level.     

A 14b 100-MS/s Time-Interleaved A/D Converter

This article presents a 14-bit, 100-MS/s time-interleaved pipeline ADC, which samples input signal from 210-MHz IF-band. Digital self-calibration is employed to compensate gain mismatch and offset between time-interleaved channels as well as mismatches arise from a single ADC channel. A timing skew-insensitive parallel S/H circuit is utilized in order to avoid timing skew between parallel ADC channels. The ADC, fabricated in a 0.35-μm BiCMOS (SiGe) takes an area of 10.2 mm², reaches an ENOB of 11.4 bits with a 79.9-dB SFDR at 192.5-MHz input and draws 1.4 W from a 3.0-V supply.