Differential Bone-Refuse Accumulation in Food-Preparation and Traffic Areas on an Early Ecuadorian House Floor

1990 ◽  
Vol 1 (2) ◽  
pp. 150-169 ◽  
Author(s):  
Peter W. Stahl ◽  
James A. Zeidler

Ethnographic observations of floor formation in an occupied and an abandoned Achuar jea dwelling structure are combined with contemporary taphonomic studies of swept and trampled surfaces. These studies suggest that refuse accumulation and incorporation are markedly different in food-preparation areas with ash deposits around fixed hearth features when compared to regularly trampled traffic areas of domestic earthen house floors. These points are examined in the horizontal and vertical analysis of highly fragmented bone remains in an Early Formative domestic house floor at the site of Real Alto, in the coastal lowlands of southwestern Ecuador. The food-preparation area of the Structure 1 house floor contained high concentrations of bone specimens characterized by their large size (over 25 mm), broad surface area, low bulk density, and greater total weight, vertically distributed throughout the ash matrix. The traffic area contained bone specimens characterized by their small size (under 25 mm), narrow surface area, high bulk density, and lower total weight, distributed unevenly in vertical profile. The horizontal distribution of fish bone only partially followed the observed pattern, as a proportionately greater amount of large fish bone was located in the traffic area. This analysis demonstrates the potential utility of bone refuse as a sensitive and reliable taphonomic indicator for inferential arguments regarding house-floor deposition.

Forests ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 223
Author(s):  
Grzegorz Trzciński ◽  
Łukasz Tymendorf ◽  
Paweł Kozakiewicz

Transport of wood biomass is one of the key operations in forestry and in the wood industry. An important part is the transport of shredded wood, where the most common forms are chips and sawdust. The aim of the research was to present the variability of the total weight of trucks (gross vehicle weight, GVW), the weight of the empty trucks (tare), and loads of chips and sawdust in different periods of the year. Changes in specific parameters were analyzed: GVW; tare weight; trailer capacity; use of the trailer load capacity; bulk volume and bulk density of wood biomass loads; solid cubic meter (m3) and weight of 1m3 of the load; and load weight depending on the season, with simultaneous measurements of wood chips and sawdust moisture. More than 250 transports from four seasons of the year were analyzed in the research. It was found that the total weight of trucks (GVW) was at a comparable level, on average from 39.42 to 39.64 Mg with slight differences (with SD 0.29 and 0.39). The weight of empty trucks was 16.15 Mg for chip-bearing trucks and 15.93 Mg for sawdust-bearing trucks (with SD 0.604 and 0.526). The type of wood material has an influence on the transported volume. The average quantity of load in the bulk cubic meter was 64.783 m3 for wood chips (SD 3.127) and 70.465 m3 (SD 2.516) for sawdust. Over 30% differences in the volume of transported wood chips and approximately 18% for sawdust were observed. The use of the loading capacity of the trailer was on average 72.58% (SD 5.567) for the transport of wood chips and 77.42% (SD 3.019) for the transport of sawdust. The sawdust bulk density was from 0.3050 to 0.4265 Mg⋅m−3 for wood chips and 0.3200 to 0.3556 Mg⋅m−3 for sawdust. This parameter is significantly dependent on moisture content, and the determined correlation functions can be used for estimating and predicting bulk density. The abovementioned absolute moisture content of chips and sawdust also depends on the season, which also affects the selected parameters of wood biomass loads.


2021 ◽  
Vol 316 ◽  
pp. 689-693
Author(s):  
K.D. Naumov ◽  
V.G. Lobanov

The aim of this paper is to establish a regulatory change of zinc powders key physicochemical properties with varying electroextraction conditions. It was studied influence zinc concentration, alkali concentration and current density. Quantitative dependencies of zinc powders particle size and specific surface area from mentioned electroextraction parameters are shown. At increasing of zinc concentration, decreasing of NaOH concentration and decreasing of current density of powders particle size growth, correspondingly specific surface area is declined. It is indicated, that electrolytic zinc powders bulk density varies from 0.61 g/cm3 to 0.75 g/cm3 with a decrease of average particle size from 121 μm to 68 μm. In comparison, spherical powders bulk density used in various industries is currently 2.45-2.6 g/cm3. In all experiments, metal zinc content varied in the range of 91.1-92.5%, the rest - ZnO. To a greater extent, this indicator depends on powder washing quality from alkali and storage conditions.


1970 ◽  
Vol 38 (3) ◽  
pp. 287-295 ◽  
Author(s):  
I. L. Craft

1. A study of the length, total weight and weight per cm of the small intestine of virgin, pregnant and lactating rats has provided evidence for an increase in intestinal surface area in pregnancy and lactation. 2. Because of such alterations in morphology of the gut the absorption,in vivo, of the substrates studied, glucose and glycine, has been expressed in terms of amount transferred per loop and also per g dry weight of intestine. 3. Using these parameters the results show that pregnancy does not alter the ability of the upper jejunum to absorb glucose and glycine. In lactation there is a significant decrease in the transfer of these substances when expressed per g dry weight of intestine, but not in absolute terms.


2018 ◽  
Vol 5 (7) ◽  
pp. 171578 ◽  
Author(s):  
P. Ravichandran ◽  
P. Sugumaran ◽  
S. Seshadri ◽  
Altaf H. Basta

This work deals with optimizing the conditions of pyrolysis and type of activator to upgrade the use of Casuarina equisetifolia fruit waste (CFW) as available and a potential precursor, in production of activated carbon (AC). In this respect, the route of activation was carried out through one- and two-step pyrolysis processes, using different chemical activating agents, such as H 3 PO 4 , KOH and ZnCl 2 . The performance of the CFW-based ACs is assessed by estimating the physico-chemical characteristics (pH, electrical conductivity, bulk density and hardness), surface morphology and scanning electron microscopy, together with carbon yield, surface area and adsorption performance of pollutants in aqueous medium (methylene blue, iodine and molasses colour removal efficiencies). The results show that the two-step activation process was more effective than one-step activation for providing high adsorption performance CFW-based ACs. The maximum Brunauer–Emmett–Teller surface area 547.89 m 2  g −1 was produced by using H 3 PO 4 activating agents, and applied two-step pyrolysis. According to the American Water Work Association and based on bulk density of the investigated ACs, we recommend that most of produced ACs are suitable for treating waste water.


2017 ◽  
Vol 5 (3) ◽  
pp. 391-397 ◽  
Author(s):  
SWAPNIL G. JAISWAL ◽  
BHUSHAN R. DOLE ◽  
SANGRAM K. SATPATHY ◽  
S.N. NAIK

Seabuckthorn is a highly perishable fruit found in trans-Himalayan region and North-Eastern part of India. It has enormous nutritional and medicinal properties. Physical attributes of fruits play an important role in the design of machines to meet various harvest and post harvest operations. In the present study properties like dimensions, true density, bulk density, sphericity, porosity and angle of repose were measured and correlated with the mass of the fruit. In addition linear, polynomial, quadratic, logarithmic and exponential models were used for mass and surface area. The length, diameter, thousand berry weight, geometric mean diameter, arithmetic mean diameter, surface area, aspect ratio, angle of repose, sphericity, porosity, true density, bulk density, moisture content were found in the range of 6.5-7.5, 4.74-6.28, 362.67-910.14, 5.49-6.99, 6.17-6.24, 76.87-154.76, 72.81-83.73, 3.59-6.82, 65.84-90.47, 17.05-60.07, 647.19-1399.24, 453.81-725.88, 84.53-87.34 respectively. Polynomial model was suited to be best for mass with length and diameter. Polynomial model between surface area and geometric mean diameter gave highest R2 of 0.981.


2017 ◽  
Author(s):  
◽  
Julian Baker

Nanoporous palladium with a specific surface area of 29.12 m2g-1 was created using highly loaded palladium hydride wires subjected to a fast electrical pulse of energy. The delivered energy of approximately 0.5 J was insufficient to melt unloaded palladium wires, but in contrast, caused highly loaded palladium hydride wires to disintegrate. An element such as palladium, which was studied in these experiments, has the capacity to store hydrogen and deuterium to extremely high concentrations. Additionally, electrical explosion experiments of palladium hydride wires were performed on single samples at the loading ratios ranging from 0.5 up to 0.96, approaching the highest experimentally achieved loading ratio of 1. It was found that nanoporous palladium was created by the pulsing of palladium hydride wires at loading ratios higher than the threshold of 0.6. Each additional increase in the hydrogen loading ratio caused an accompanying increase in the surface area. In contrast, when the hydrogen loading ratio was below 0.6 the wire remained intact and there was no nanoporosity produced. Finally, a novel calorimetry technique was used to determine the relative amount of energy released from a wire during a fast, low energy pulse. Statistical analysis using Dunnett's T3 test with a significance level of 0.05 was performed on the experimental data, and showed a statistical difference between the means of the control (i.e. unloaded palladium wires) when compared to PdH0.72 and PdH0.9, and a statistical difference when comparing the control mean to PdD0.5 and PdD0.87.


2021 ◽  
Author(s):  
Lingayya Hiremath ◽  
O. Sruti ◽  
B.M. Aishwarya ◽  
N.G. Kala ◽  
E. Keshamma

This study aimed to introduce antibacterial nanofibers, produced by electrospinning as a novel technique in constructing nanostructured materials. The large size and less bioavailability due to impenetrable (or partial/improper penetration) membrane has resulted in production of nanofibers. These nano sized Fibers were successful in delivering the active ingredients and served the purpose of using plants for its cause. Some of the active ingredients include antimicrobial compounds that are incorporated into various products to prevent unwanted microbial growth. As higher bioavailability is one of the most crucial parameters when it comes to medical solutions, electro spun nanofibers are highly preferred. This method is preferable for organic polymers as they have high flexibility, high specific surface area and surface functionalization. Electrospinning technology has been used for the fabrication and assembly of nanofibers into membranes, which have extended the range of potential applications in the biomedical, environmental protection, nanosensor, electronic/optical, protective clothing fields and various other fields.


2009 ◽  
Vol 55 (No. 4) ◽  
pp. 165-169 ◽  
Author(s):  
M.C. Ndukwu

The research looked at some selected physical properties of <I>Brachystegia eurycoma</I>, such as axial dimension, roundness, sphericity, surface area, bulk density, solid density, porosity, and volume which are essential in the design and construction of the processing and handling equipments of <I>Brachystegia eurycoma</I>. All the above physical properties measured showed some deviations from the average values which is typical of agricultural biomaterials. Solid density showed the highest deviation of 4.04 g/mm<sup>3</sup> while the volume showed the least deviation of 0.01 mm<sup>3</sup> when compared to those of other physical properties. The angle of repose increased with the increase in the moisture content with a coefficient of determination of 0.98.


Sign in / Sign up

Export Citation Format

Share Document