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The research aimed to identify two sets of charcoal found in a Hellenistic house in Risan (Montenegro) on the Kotor Gulf. The finds date from the 3rd century BC.The study included macroscopic and microscopic observations. Based on macroscopic observation and taking into account the habitat requirements and the range of particular species near Risan and the Kotor Gulf, the first set of charcoal found near a ceramic vessel was attributed to fir wood (Abies sp.), while the charcoal found in the room “with the treasure” was attributed to oak wood (Quercus sp.). The study has added to the body of evidence in favor of the effective botanical identification of charcoal from archeological finds.
Performance characterization of some selected conventional cook stoves in South Eastern Nigeria had been carried out. Three conventional cook stoves (3-stone stove, charcoal stove and sawdust stove) were selected and evaluated. Their performances were compared with those of improved stove. The results show that the time spent in cooking 1 Kg of rice/(yam) is significantly different in all the conventional stoves under test; (maximum 0.75 (0.44) kg/hr for 3-stone stove and minimum 0.61 (0.35) hr/kg for charcoal). Fuel utilization also differs for instance lesser quantity of charcoal would be required to cook the same quantity of food on the charcoal stove than the open fire stove. Also the specific fuel consumption value of charcoal stove is lesser than all other stoves. The 3-stone stove have higher specific fuel consumption values indicative of more fuel consumption but lower thermal efficiency. This indicates a poor performance when compared to other improved stoves such as kerosene stove with higher thermal efficiency of 64.38 %.
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A novel biocompatibility test for disperse materials

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Introduction. Development of novel biocompatibility tests represents an urgent problem. Use of chicken embryos minimizes the effect of exogenous factors on the experimental course (as the chicken embryo develops in medium it is almost completely isolated from external effects), enables the observation of physiological and pathological processes in the dynamics and assessment of the response of the body response to various materials in many cell populations. Objective. We aimed to show the possibility of using chicken embryo as a test system for evaluation of the biological effects of powdered materials. Materials and methods. In this study, we applied developing chicken embryos produced by incubation of Highline white eggs. Test and control groups (200 embryos in total) were used. Powdered materials were introduced into the embryo yolk sac in the form of suspension in biocompatible dextran (rheopolyglucine).The material was sterilized for 60 min at 120 °С. Two disperse materials, activated charcoal and asbestos powders, were selected to assess the capabilities of the method. Morphological (review, selective histochemical, and electron microscopy) examination methods were applied in testing, which produced the following results. Results. Model efficacy was confirmed by testing certain substances, such as activated charcoal and asbestos. Faster growth and accelerated development of chicken embryos, the absence of tissue pathological reactions, was indicative of the biocompatibility of activated charcoal. Poor biocompatibility of asbestos was concluded from its multiple teratogenic effects detected for the first time for this material. Conclusions.The paper contains motivation and experimental data regarding the usability of chicken embryos in integrated testing of disperse material biocompatibility.
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The objective of this study was to determine whether silica grit is a necessary dietary additive for turkeys raised in intensive production farms, and whether it can be replaced by other supplements such as charcoal or hardwood ash. The conclusions were formulated based on performance results, blood hematological and biochemical indices, the slaughter quality of turkeys, as well as on the chemical and physicochemical properties of turkey meat. The experimental material comprised 360 male Big 6 heavy-type turkeys randomly divided into 4 treatments and raised on litter until 20 weeks of age. Birds of all treatments were fed identical complete pelleted basal diets. The experimental factor were various feed supplements in each group. The control treatment was fed a diet without supplements. The diets for experimental groups were supplemented with silica grit (SG), charcoal (CH) or hardwood ash (HA) in the amount of 0.3% of the administered feed mix. Dietary supplements were administered from the first day of life until the end of the rearing period. No significant changes in blood hematological and biochemical indices of turkeys were observed. Silica grit (SG) had an adverse effect on the performance results of turkeys, while the addition of both CH and HA had a highly beneficial impact. The best results were reported in respect of charcoal. The treatment fed a diet supplemented with CH was characterized by the lowest mortality rate of 4.4%, i.e. half that observed in the control group, body weight higher by 3.9% and rearing efficiency index higher by 9.7%.
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Analysis of sawmill waste charring process in the steel retorts. There is described the process of sawmill waste charring in the steel retorts that belong to the contractor operating in Forest Inspectorate Kozienice. The process consists of nine stages and lasts over 76 hours, including 14 h (19%) of the effective charring, 47 h (62%) of cooling the retorts, and the remaining 15 h for cleaning, loading and unloading of the retort. The economic analysis for the assumed data showed that average specific cost of obtaining a 2.5-kg bag of charcoal made of sawmill waste was equal to about 5 PLN, while the limit profitability point, calculated for the process with the use of a new retort, amounted to 87 bags of charcoal, and with the depreciated retort – 67 bags.
Taxonomic identification on the basis of wood anatomy showed that 68.82% of wood charcoals from the Early Bronze Age Site at Yenibademli, on Gökçeada Island (Imbros) in the Northern Aegean region of Turkey belong to the genus Quercus, 15.88% to Pinus, 13.51% to Phillyrea, 0.63% to Arbutus, 0.35% to Ulmus, and 0.23% to the Rosaceae family. The results revealed that the dominant tree genus was oak (Quercus sp.), 67.2% of which was deciduous oak, and the remaining 1.62% was evergreen oak. Quercus and Pinus as the most common two genera in the spectrum of taxa may have a link with oak and pine stands on Gökçeada (Imbros) in the Early Bronze Age. Moreover, the evergreen Quercus (sec. Ilex) and the genus Phillyrea, which was third in the spectrum, suggest that maquis and open vegetation were also present in the Early Bronze Age on Gökçeada.
The purpose of this study has been to determine the effect of soil contamination with fluorine on the content of phosphorus in crops. Alongside the simulated fluorine soil pollution, substances neutralizing this xenobiotic, such as lime, charcoal and loam, were applied to soil. Depending on the sensitivity of the plants, the degree of soil pollution with fluorine was: 1) 0, 20, 40 and 60 mg F kg-1 of soil under sensitive crops, i.e. narrow-leaf lupine; 2) 0, 50, 100 and 150 mg F kg-1 of soil under moderately sensitive crops, i.e. seed lucerne; 3) 0, 100, 200 and 300 mg F kg-1 of soil under more tolerant crops, i.e. maize, winter oilseed rape, spring triticale, black radish and phacelia. The content of phosphorus varied, depending on the level of soil contamination with fluorine and substances applied to inactivate this element, as well as on the species and organ of the examined plants. An increasing degree of soil pollution with fluorine contributed to raising the phosphorus content in black radish, in aerial biomass of yellow lupine and in roots of spring triticale. Regarding the maize roots, a reverse dependence was recorded. The highest phosphorus content appeared in roots of winter oilseed rape (8.16 g P kg-1 d.m.) and black radish (7.33 g P kg-1 d.m.), while the lowest one was in roots of spring triticale (0.86 g P kg-1 d.m.). Overall, the applied neutralizing substances resulted in lower concentrations of phosphorus in the analyzed plant organs, with the most univocal influence achieved in aerial biomass of yellow lupine, in roots of narrow-leaf lupine, in aerial mass and roots of black radish and in aerial biomass from the first cut of seed lucerne. In respect of the other plants, the impact of the neutralizing substances on the content of phosphorus was also significant albeit dependent on their species.
Twenty fattened gilts aged about 170 days and weighing 90-100 kg were used in a 14-days feeding experiment (4 groups of 5 animals). Gilts of all groups were offered 3 kg of balanced feed daily. Feed used for control group (C) was free from ochratoxin A (OTA) and from mycotoxins ZEN, AFT, DON,while that for all experimental groups (E1, E2, E3) contained 32,2 μg naturally ocurring OTA/kg.Feed used for group E1 contained an additive of 0.3 kg activated charcoal while that for group E2 – 0.125 kg aluminosilicate/100 kg. Feed used for E3 group contained no OTA-inactivating agents.The post-slaughter laboratory analyses were done of blood serum, kidney, liver and longissimus dorsi muscle. All E groups showed similar concentrations of OTA in the examined tissues. Concentration of 32.2 μg OTA/kg feed offered led neither to disease in gilts nor to increase of the creatinine and urea nitrogen level in their blood sera. Both adsorbents did not lead to decrease in micro- and macroelements in the sera of gilts. It is concluded that adsorption of OTA was not effective in its inactivation when adsorbents were used in the applied dozes.
There are 18 Quercus species in Turkey, and Quercus vulcanica, called “Kasnak oak” in Turkish, is an endemic species. The Kasnak oak has been studied in three localities where the well formed communities of this species exist. The evaluation of bioclimatic tolerance ranges of Kasnak oak in Turkey was the aim of the study. Overall results support that Kasnak oak prefers humid conditions in ambient habitat.
Celem przeprowadzonych badań było określenie oddziaływania substancji neutralizujących wpływ zanieczyszczenia gleby arsenem na zawartość wapnia w wybranych roślinach uprawnych. Były to: wapno, dolomit, zeolit naturalny i syntetyczny, węgiel drzewny, ił i kompost. Zawartość wapnia była zróżnicowana w zależności od zanieczyszczenia podłoża arsenem i dodatków neutralizujących oraz od gatunku i organu roślin. W serii bez dodatków neutralizujących wykazano istnienie dodatniej zależności pomiędzy poziomem zanieczyszczenia podłoża arsenem a zawartością wapnia w częściach nadziemnych i korzeniach kukurydzy, w korzeniach brukwi pastewnej oraz w ziarnie i słomie jęczmienia jarego. Najwyższe zanieczyszczenie gleby arsenem (100 mg As·kg⁻¹ gleby) działało ujemnie na zawartość wapnia w korzeniach kukurydzy i jęczmienia. W przypadku pozostałych organów roślin zmiany te były mniejsze i mniej jednoznaczne. Najbardziej jednoznaczny wpływ substancji neutralizujących stwierdzono w korzeniach kukurydzy, w częściach nadziemnych łubinu żółtego oraz w ziarnie, słomie i korzeniach jęczmienia jarego, w których następowało na ogół zmniejszenie oraz w korzeniach kupkówki pospolitej i łubinu żółtego oraz w częściach nadziemnych i korzeniach brukwi pastewnej, gdzie wykazano zwiększenie zawartości wapnia.
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