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In order to expand the zero-energy building, it is necessary to evaluate the economic feasibility of the passive and active elements applied to achieve the zero-energy building. The purpose of this study is to verify the final energy consumption and investment cost of a building according to the change of passive and active elements. In this study, the final energy consumption was calculated by region for the passive element S/V ratio (surface-to-volume ratio), the building's orientation, and the active element (building-integrated photovoltaic) for the Department of Energy reference building type using simulations. In addition, the change in investment cost according to changes in energy consumption and production was calculated. As a result of the study, it was reasonable to invest in passive elements rather than active elements in the central region of Korea, and it was confirmed that investment in active elements was highly economical in the southern region of Korea. It is expected that the results of this study can be used as a guideline to enable the economic analysis of design elements in the design of zero-energy buildings. [ABSTRACT FROM AUTHOR]

In order to expand the zero-energy building, it is necessary to evaluate the economic feasibility of the passive and active elements applied to achieve the zero-energy building. The purpose of this study is to verify the final energy consumption and investment cost of a building according to the change of passive and active elements. In this study, the final energy consumption was calculated by region for the passive element S/V ratio (surface-to-volume ratio), the building’s orientation, and the active element (building-integrated photovoltaic) for the Department of Energy reference building type using simulations. In addition, the change in investment cost according to changes in energy consumption and production was calculated. As a result of the study, it was reasonable to invest in passive elements rather than active elements in the central region of Korea, and it was confirmed that investment in active elements was highly economical in the southern region of Korea. It is expected that the results of this study can be used as a guideline to enable the economic analysis of design elements in the design of zero-energy buildings.

The objective of this study is to derive a design methodology for a zero-energy building considering the energy production and consumption of the building. In order to establish the design methodology, various factors affecting the energy production and consumption of the building are derived, and the effect of the heat transmission rate, the surface to volume ratio (S/V ratio), the location and the orientation of the building are analyzed by simulation method. As a result, the S/V ratio and the heat transmission rate are the most important factors in the central region of Korea where consumes large amounts of heating and cooling energy. This is because the final energy consumption varies depending on the heat loss through the envelope. It was confirmed that solar power generation is the most important factor in the southern regions of Korea where the energy consumption is relatively small. The final energy consumption varies depending on the solar power generation in these areas. Therefore, when designing a zero-energy building, the zero-energy of the building can be achieved by using the design methodology established in this study. [ABSTRACT FROM AUTHOR]

It has been shown that size of planktonic diatoms responds to changes in water chemistry, but little is known about the influence of different types of environmental factors upon benthic diatom size variation. Here we ask whether water chemistry or hydromorphological influences show a stronger effect on benthic diatom morphometry. 10,624 diatom valves / frustules were imaged, identified and measured from 48 samples across eight sites in the Ebro river basin obtained during ten years of biomonitoring work. We analysed how differences in surface-to-volume (S/V) ratio and other morphometric characteristics were related to spatial and temporal variability in environmental parameters. Our results show that both hydrological and physicochemical variables generated significant responses in interspecific and intraspecific morphometric variation. S/V ratio and transapical width showed the strongest responses, followed by (the predominantly used) cell volume. Freshwater benthic diatom morphology seems to respond to diverse environmental factors and could provide complementary ecological information to community composition. [ABSTRACT FROM AUTHOR]

The objective of this study is to derive a design methodology for a zero-energy building considering the energy production and consumption of the building. In order to establish the design methodology, various factors affecting the energy production and consumption of the building are derived, and the effect of the heat transmission rate, the surface to volume ratio (S/V ratio), the location and the orientation of the building are analyzed by simulation method. As a result, the S/V ratio and the heat transmission rate are the most important factors in the central region of Korea where consumes large amounts of heating and cooling energy. This is because the final energy consumption varies depending on the heat loss through the envelope. It was confirmed that solar power generation is the most important factor in the southern regions of Korea where the energy consumption is relatively small. The final energy consumption varies depending on the solar power generation in these areas. Therefore, when designing a zero-energy building, the zero-energy of the building can be achieved by using the design methodology established in this study.

Ferrates have attracted considerable research in the last few decades because their activity is not associated with toxic byproducts. This research investigated the effect of three factors on ferrate (VI) synthesis using an electrochemical reactor: electrolyte concentration, current density, electrode effective surface: electrolyte volume ratio (S/V ratio). The results of ferrate(VI) production using two different membranes were compared. Electrolyte concentration had the greatest effect on ferrate( VI) production. Ferrate(VI) concentration of 250 mmol dm-3 was achieved using 20 mol dm-3 of NaOH electrolyte, current density of 80 Am-2, and 2.21 S/VAn during five hours of electrolysis. A cost analysis of the consumable components such as the electrolyte, electric energy, and dissolved iron demonstrated that the electrolyte concentration had the greatest influence. [ABSTRACT FROM AUTHOR]

NMR relaxometry has developed into a method for rapid pore-size determination of natural porous media. Nevertheless, it is prone to uncertainties because of unknown surface relaxivities which depend mainly on the chemical composition of the pore walls as well as on the interfacial dynamics of the pore fluid. The classical approach for the determination of surface relaxivities is the scaling of NMR relaxation times by surface to volume ratios measured by gas adsorption or mercury intrusion. However, it is preferable that a method for the determination of average pore sizes uses the same substance, water, as probe molecule for both relaxometry and surface to volume measurements. One should also ensure that in both experiments the dynamics of the probe molecule takes place on similar length scales, which are in the order of some microns. Therefore, we employed NMR diffusion measurements with different observation times using bipolar pulsed field gradients and applied them to unconsolidated sediments (two purified sands, two natural sands, and one soil). The evaluation by Mitra's short-time model for diffusion in restricted environments yielded information about the surface to volume ratios which is independent of relaxation mechanisms. We point out that methods based on NMR diffusometry yield pore dimensions and surface relaxivities consistent with a pore space as sampled by native pore fluids via the diffusion process. This opens a way to calibrate NMR relaxation measurements with other NMR techniques, providing information about the pore-size distribution of natural porous media directly from relaxometry. [ABSTRACT FROM AUTHOR]

To evaluate the role of biofilms in improving microbial quality in rainwater tanks, the cell number of Pseudomonas aeruginosa was investigated after inoculation in pilot and full-scale rainwater tanks with different surface-to-volume (S/V) ratios. In pilot-scale experiments, the total number of inoculated cells sampled from the tank water, bottom and walls decreased. After 4 and 5 d, 99% of the inoculated cells were removed from the water in pilot tanks 2 and 1, respectively. Cell death due to low-nutrient conditions contributed to the observed cell number decline. The high removal rate in pilot tank 2 was because of the high S/V ratio. Further, the high removal rate of planktonic P. aeruginosa in full-scale experiment was confirmed in the tanks with high S/V ratios. Our observations indicated that biofilms play a significant role in improving the quality of stored rainwater. [ABSTRACT FROM AUTHOR]

The impact of field-grown transgenic trees on wood characteristics and enzymatic saccharification was evaluated. Genes 4CL and CAld5H were down regulated or overexpressed to modify the lignin content or structure (S/V ratio) on black cottonwood ( Populus trichocarpa Nisqually-1). These transgenic trees were grown in the real environment and evaluated after 2 and 3 years. The results exhibited that the lignin content for most of the transgenic black cottonwoods increased compared to their initial lignin content when grown inside the greenhouse. The lignin contents approached those of the wild types. Acid and green-liquor pretreatments were applied to the transgenic wood saw dust samples. Cellulase mediated saccharifications were then conducted for the pretreated and untreated samples. Sugar yield and carbohydrate saccharification efficiency of the enzymatic saccharification for most of the transgenic trees were observed to be higher than those of the wild types even though their lignin contents became similar. [ABSTRACT FROM AUTHOR]

The structural features of bast fiber and core lignins in kenaf ( Hibiscus cannabinus), bark and wood lignin of paper mulberry ( Broussonetia papyrifera (L.) Vent × Broussonetia kazinoki Sieb.) and mulberry ( Morus bombycis) were characterized by alkaline nitrobenzene oxidation, ozonation and methoxyl group determination. Björkman lignins were isolated from bast fiber and core, and bark and wood fractions of the plant samples, and structural characteristics were investigated by H NMR and C NMR spectroscopies. Kenaf bast fiber gave very high molar ratio of syringaldehyde to vanillin (S/V) of alkaline nitrobenzene oxidation products, while methoxyl content was about the same as that of the core fraction. Results of H NMR and C NMR of Björkman lignin suggested the presence of aliphatic fragments in lignins isolated from paper mulberry and mulberry bark, but not in kenaf bast fiber. The lower yield of alkaline nitrobenzene oxidation products from bast fiber and bark might be due to the higher content of condensed structure of lignin compared to core fraction. Total yield of erythronic ( E) and threonic ( T) acids of ozonation products and the molar ratio of erythronic acid to threonic acid ( E/ T) of the bast fibers and bark were lower than the corresponding core and wood fractions, suggesting that the contents of arylglycerol-β-aryl ether intermonomer linkages in the bast fiber and bark lignin were lower than those of the core and wood fractions. Methoxyl content of bark lignin was lower than the corresponding wood lignin. The methoxyl content of the extract-free kenaf bast fiber was similar to that of the core fraction, while the values of paper mulberry and mulberry bark were about one-half of the corresponding wood fractions, respectively. In bark lignins, the methoxyl contents of Klason lignin and Björkman lignin from bark were lower than those of the extract-free barks. This result suggests that the purity of Klason lignin and Björkman lignins of bark may be rather low. [ABSTRACT FROM AUTHOR]

In this study, the microbial characteristics of rainwater in two tanks with different surface-to-volume ratios were investigated and compared to determine how the internal design features of storage tanks affect water quality. The particle and nutrient parameters of the rainwater, including turbidity, suspended solids, total organic carbon, and total phosphate, were lower in Tank 2, which had a surface-to-volume ratio 7.5 times greater than that of Tank 1. In addition, although the rainwater was collected from the same catchment area, the water in Tank 1 had greater numbers of bacteria, and the bacterial communities in the water differed between the two storage tanks. It appears that the differences in the inside surface structures of the rainwater tanks affected the microbial ecosystems. Increasing the surface-to-volume ratio in rainwater tanks may affect rainwater quality, because this extends the area for biofilm development. Further study of the role of biofilm in rainwater tank is required precisely, and its function needs to be considered in the design and management of rainwater tanks. [ABSTRACT FROM AUTHOR]

Morphological variation related to pH was investigated in two acidophilic desmid species ( Euastrum binale var. gutwinskii and Staurastrum hirsutum) utilizing geometric morphometric methods. Clones isolated from acidic habitats were cultured using a range of pH values from 3.5 to 6.5. The plasticity of ensuing populations was quantified and illustrated by the general Procrustes superimposition of landmarks placed along the outline of cells and subsequent statistical analyses of shape data. In both species, there was a significant effect of pH on the morphology of cells. In Staurastrum hirsutum, the pH-related morphological change was accompanied by a decrease in the size of cells cultured at a higher pH. However, in Euastrum binale, cell size did not differ in relation to pH, but cell shape was characterized by a deepening of the incisions between cell lobes at higher pH. In both species, cell complexity based on surface-to-volume ratio was positively correlated with increasing pH. We conclude that by manipulating their surface-to-volume ratios, these desmid species can respond to pH variations in their environment. [ABSTRACT FROM AUTHOR]

The self-diffusion of water and hexadecane in medium and coarse sands from glacial sand deposits in central Germany were investigated by pulsed field gradient nuclear magnetic resonance (PFG NMR). Due to the restriction of the diffusion path at the pore/grain interface, the measured apparent self-diffusion coefficients (D(Δ)) in the pore space depend on the observation time (Δ) in the PFG NMR experiment. Although the bulk self-diffusion coefficients of water and hexadecane differ by about one order of magnitude, the apparent self-diffusion coefficients in the pore space obey the same characteristic time-behaviour, which depends only on geometrical properties of the pore system. Using the “short-time diffusion” model, surface-to-volume (S/V) ratios and inherent self-diffusion coefficients (D0) of the pore fluids were extracted from these diffusion measurements. The S/V ratios obtained are independent of the pore fluid used and agree with known geometrical properties of the sand grains. Moreover, the D0 values are consistent with the corresponding bulk self-diffusion coefficients measured separately. In contrast to these results of PFG NMR, simultaneous investigations of longitudinal (T1) nuclear magnetic relaxation reveal that the relaxation time of the pore fluid is a less suitable parameter for a quantitative estimation of geometrical properties of the pore/grain interface in these unconsolidated sediments since it depends on chemical properties of the fluid/grain interface. [Copyright &y& Elsevier]