Maximum window-to-wall ratio of a thermally autonomous building as a function of envelope U -value and ambient temperature amplitude

2015 ◽  
Vol 146 ◽  
pp. 84-91 ◽  
Author(s):  
Peizheng Ma ◽  
Lin-Shu Wang ◽  
Nianhua Guo
Keyword(s):  
Ambient Temperature ◽  
U Value ◽  
Temperature Amplitude

scholarly journals Temperature fluctuation improves oil palm (Elaeis guineensis) dura × pisifera seed germination

2020 ◽  
Vol 48 (1) ◽  
pp. 49-55 ◽  
Author(s):  
M.G. Norsazwan ◽  
U.R. Sinniah ◽  
A.B. Puteh ◽  
P. Namasivayam ◽  
M. Mohaimi ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Seed Germination ◽  
Ambient Temperature ◽  
Seed Production ◽  
Constant Temperature ◽  
Oil Palm ◽  
Temperature Fluctuation ◽  
Daily Maximum ◽  
Seed Processing ◽  
Temperature Amplitude

Oil palm is mainly propagated using dura × pisifera (D × P) hybrid seeds. Among the issues in D × P seed production are relatively poor seed germination and uniformity, despite heat treatment at 40°C to break dormancy. The conditions for germination post-heat-treatment may be a contributing factor. This study aimed to evaluate and compare the effect of constant 30°C or ambient temperature fluctuation at two different locations, Sime Darby Oil Palm Breeding Seed Processing Renggam, Johor and the Seed Production Unit (SPU) Banting, Selangor on oil palm D × P seed germination. At both locations, final mean germination percentage and speed were higher at fluctuating temperatures compared with constant 30°C. Under fluctuating conditions, the Oil Palm Breeding Seed Processing Renggam environment resulted in higher germination (85.8%) compared with SPU Banting (69.8%). Thus, the higher temperature amplitude (difference between daily maximum and minimum temperatures) was an important factor, resulting in higher germination. Therefore, oil palm can be germinated under ambient temperature conditions to obtain higher germination than under constant temperature, avoiding the need for maintaining expensive constant temperature germination rooms. In addition, a sufficiently high temperature amplitude can be beneficial in improving the ability to germinate and the speed of germination.

scholarly journals Variation in reproductive investment increases body temperature amplitude in a temperate passerine

Oecologia ◽  
2021 ◽  
Vol 197 (2) ◽  
pp. 365-371
Author(s):  
Jan-Åke Nilsson ◽  
Andreas Nord
Keyword(s):  
Body Temperature ◽  
Ambient Temperature ◽  
Circadian Variation ◽  
Reproductive Investment ◽  
Work Rate ◽  
Pronounced Increase ◽  
The Difference ◽  
Predicted Values ◽  
High Work ◽  
Temperature Amplitude

AbstractMany birds and mammals show substantial circadian variation in body temperature, which has been attributed to fluctuations in ambient temperature and energy reserves. However, to fully understand the variation in body temperature over the course of the day, we also need to consider effects of variation in work rate. We made use of a dataset on body temperature during the resting and active periods in female marsh tits (Poecile palustris) that bred in a temperate area and were subjected to experimental changes in reproductive investment through brood size manipulations. Furthermore, the amplitude increased with daytime, but were unaffected by nighttime, ambient temperature. Amplitudes in females with manipulated broods were 44% above predictions based on inter-specific allometric relationships. In extreme cases, amplitudes were > 100% above predicted values. However, no individual female realised the maximum potential amplitude (8.5 °C, i.e. the difference between the highest and lowest body temperature within the population) but seemed to prioritise either a reduction in body temperature at night or an increase in body temperature in the day. This suggests that body temperature amplitude might be constrained by costs that preclude extensive use of both low nighttime and high daytime body temperatures within the same individual. Amplitudes in the range found here (0.5–6.7 °C) have previously mostly been reported from sub-tropical and/or arid habitats. We show that comparable values can also be found amongst birds in relatively cool, temperate regions, partly due to a pronounced increase in body temperature during periods with high work rate.

SEM of non-coated hepatocellular cytoskeleton of perfused livers

1984 ◽  
Vol 42 ◽  
pp. 306-307
Author(s):  
S.W. French ◽  
N.C. Benson ◽  
C. Davis-Scibienski
Keyword(s):  
Ambient Temperature ◽  
Critical Point ◽  
Protease Inhibitors ◽  
Metal Deposition ◽  
Heat Damage ◽  
Detergent Extraction ◽  
Cytoskeletal Elements ◽  
Triton X ◽  
Excised Tissue

Previous SEM studies of liver cytoskeletal elements have encountered technical difficulties such as variable metal coating and heat damage which occurs during metal deposition. The majority of studies involving evaluation of the cell cytoskeleton have been limited to cells which could be isolated, maintained in culture as a monolayer and thus easily extracted. Detergent extraction of excised tissue by immersion has often been unsatisfactory beyond the depth of several cells. These disadvantages have been avoided in the present study. Whole C3H mouse livers were perfused in situ with 0.5% Triton X-100 in a modified Jahn's buffer including protease inhibitors. Perfusion was continued for 1 to 2 hours at ambient temperature. The liver was then perfused with a 2% buffered gluteraldehyde solution. Liver samples including spontaneous tumors were then maintained in buffered gluteraldehyde for 2 hours. Samples were processed for SEM and TEM using the modified thicarbohydrazide procedure of Malich and Wilson, cryofractured, and critical point dried (CPD). Some samples were mechanically fractured after CPD.

Formation of Dislocation Channels in Neutron Irradiated Molybdenum

1972 ◽  
Vol 30 ◽  
pp. 672-673
Author(s):  
S. Mahajan
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Ambient Temperature ◽  
Room Temperature ◽  
Channel Formation ◽  
Early Stages ◽  
Transmission Electron ◽  
Three Stages ◽  
Two Stages ◽  
Polycrystalline Molybdenum

The evolution of dislocation channels in irradiated metals during deformation can be envisaged to occur in three stages: (i) formation of embryonic cluster free regions, (ii) growth of these regions into microscopically observable channels and (iii) termination of their growth due to the accumulation of dislocation damage. The first two stages are particularly intriguing, and we have attempted to follow the early stages of channel formation in polycrystalline molybdenum, irradiated to 5×1019 n. cm−2 (E > 1 Mev) at the reactor ambient temperature (∼ 60°C), using transmission electron microscopy. The irradiated samples were strained, at room temperature, up to the macroscopic yield point.Figure 1 illustrates the early stages of channel formation. The observations suggest that the cluster free regions, such as A, B and C, form in isolated packets, which could subsequently link-up to evolve a channel.

Crystallographic Characterization of Dislocation Loops in Irradiated Tungsten

1968 ◽  
Vol 26 ◽  
pp. 290-291
Author(s):  
Robert C. Rau
Keyword(s):  
Electron Microscope ◽  
Ambient Temperature ◽  
Dislocation Loops ◽  
Polycrystalline Specimen ◽  
Post Irradiation ◽  
Neutron Fluences

Previous work has shown that post-irradiation annealing, at temperatures near 1100°C, produces resolvable dislocation loops in tungsten irradiated to fast (E > 1 MeV) neutron fluences of about 4 x 1019 n/cm2 or greater. To crystallographically characterize these loops, tilting experiments were carried out in the electron microscope on a polycrystalline specimen which had been irradiated to 1.5 × 1021 n/cm2 at reactor ambient temperature (∼ 70°C), and subseouently annealed for 315 hours at 1100°C. This treatment produced large loops averaging 1000 Å in diameter, as shown in the micrographs of Fig. 1. The orientation of this grain was near (001), and tilting was carried out about axes near [100], [10] and [110].

Voids in Quenched Nickel

1968 ◽  
Vol 26 ◽  
pp. 266-267
Author(s):  
J. J. Laidler
Keyword(s):  
Electron Beam ◽  
Ambient Temperature ◽  
Cooling Rate ◽  
Three Dimensional ◽  
Cooling Curve ◽  
Polycrystalline Nickel ◽  
Quenching Temperature ◽  
Long Tail ◽  
Diffusion Pump

The presence of three-dimensional voids in quenched metals has long been suspected, and voids have indeed been observed directly in a number of metals. These include aluminum, platinum, and copper, silver and gold. Attempts at the production of observable quenched-in defects in nickel have been generally unsuccessful, so the present work was initiated in order to establish the conditions under which such defects may be formed.Electron beam zone-melted polycrystalline nickel foils, 99.997% pure, were quenched from 1420°C in an evacuated chamber into a bath containing a silicone diffusion pump fluid . The pressure in the chamber at the quenching temperature was less than 10-5 Torr . With an oil quench such as this, the cooling rate is approximately 5,000°C/second above 400°C; below 400°C, the cooling curve has a long tail. Therefore, the quenched specimens are aged in place for several seconds at a temperature which continuously approaches the ambient temperature of the system.

Impact of roof shading on building energy performance in warm & humid climatic places of India

2020 ◽  
pp. 50-64
Author(s):  
Kuladeep Kumar Sadevi ◽  
Avlokita Agrawal
Keyword(s):  
Energy Consumption ◽  
Energy Conservation ◽  
Energy Performance ◽  
General Assumption ◽  
Climatic Conditions ◽  
Building Envelope ◽  
Passive Cooling ◽  
Base Case ◽  
U Value ◽  
The Impact

With the rise in awareness of energy efficient buildings and adoption of mandatory energy conservation codes across the globe, significant change is being observed in the way the buildings are designed. With the launch of Energy Conservation Building Code (ECBC) in India, climate responsive designs and passive cooling techniques are being explored increasingly in building designs. Of all the building envelope components, roof surface has been identified as the most significant with respect to the heat gain due to the incident solar radiation on buildings, especially in tropical climatic conditions. Since ECBC specifies stringent U-Values for roof assembly, use of insulating materials is becoming popular. Along with insulation, the shading of the roof is also observed to be an important strategy for improving thermal performance of the building, especially in Warm and humid climatic conditions. This study intends to assess the impact of roof shading on building’s energy performance in comparison to that of exposed roof with insulation. A typical office building with specific geometry and schedules has been identified as base case model for this study. This building is simulated using energy modelling software ‘Design Builder’ with base case parameters as prescribed in ECBC. Further, the same building has been simulated parametrically adjusting the amount of roof insulation and roof shading simultaneously. The overall energy consumption and the envelope performance of the top floor are extracted for analysis. The results indicate that the roof shading is an effective passive cooling strategy for both naturally ventilated and air conditioned buildings in Warm and humid climates of India. It is also observed that a fully shaded roof outperforms the insulated roof as per ECBC prescription. Provision of shading over roof reduces the annual energy consumption of building in case of both insulated and uninsulated roofs. However, the impact is higher for uninsulated roofs (U-Value of 3.933 W/m2K), being 4.18% as compared to 0.59% for insulated roofs (U-Value of 0.33 W/m2K).While the general assumption is that roof insulation helps in reducing the energy consumption in tropical buildings, it is observed to be the other way when insulation is provided with roof shading. It is due to restricted heat loss during night.

STUDY ON DEVELOPMENT OF PASTA PRODUCT WITH INCORPORATION OF OCIMUM SANCTUM (BASIL) TO ENHANCE THE SENSORY AND NUTRITIONAL QUALITY

2018 ◽  
Vol 24 (2) ◽  
Author(s):  
PIYUSH MISHRA ◽  
DEVENDRA KUMAR BHATT
Keyword(s):  
Ambient Temperature ◽  
Shelf Life ◽  
Nutritional Quality ◽  
Leaf Extract ◽  
Storage Stability ◽  
Natural Antioxidants ◽  
Sensory Properties ◽  
Ocimum Sanctum ◽  
Leaf Powder

Pasta was prepared by incorporation of Ocimum sanctum (Basil) for better textural and sensory properties. The pasta was incorporated with the leaf extract of Ocimum sanctum at different concentrations of control, 5, 10, and 15.The natural antioxidants present in the O. sanctum leaf powder that was incorporated in the fruit leather showed extended shelf-life over three months when compared with control, without any added preservative at ambient temperature. Also the nutritional stability of the product was studied under two flexible packages of polypropylene and polyester out of that the products packed in polypropylene showed better storage stability .

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