Environmentally Safe, Large Volume Utilization Applications for Gasification Byproducts

Samples of gasification by-products produced at Polk Station and Eastman Chemical were obtained and characterized. Bulk samples were prepared for utilization studies by screening at the appropriate size fractions where char and vitreous frit distinctly partitioned. Vitreous frit was concentrated in the +20 mesh fraction while char predominated in the -20+100 mesh fraction. The vitreous frit component derived from each gasifier slag source was evaluated for use as a pozzolan and as aggregate. Pozzolan testing required grinding the frit to very fine sizes which required a minimum of 60 kwhr/ton. Grinding studies showed that the energy requirement for grinding the Polk slag were slightly higher than for the Eastman slag. Fine-ground slag from both gasifiers showed pozzoalnic activity in mortar cube testing and met the ASTM C618 strength requirements after only 3 days. Pozzolanic activity was further examined using British Standard 196-5, and results suggest that the Polk slag was more reactive than the Eastman slag. Neither aggregate showed significant potential for undergoing alkali-silica reactions when used as concrete aggregate with ASTM test method 1260. Testing was conducted to evaluate the use of the frit product as a component of cement kiln feed. The clinker produced was comprised primarily of the desirable components Ca{sub 3}SiO{sub 5} and Ca{sub 2}SiO{sub 4} after raw ingredient proportions were adjusted to reduce the amount of free lime present in the clinker. A mobile processing plant was designed to produce 100 tons of carbon from the Eastman slag to conduct evaluations for use as recycle fuel. The processing plant was mounted on a trailer and hauled to the site for use. Two product stockpiles were generated; the frit stockpile contained 5% LOI while the carbon stockpile contained 62% LOI. The products were used to conduct recycle fuel tests. A processing plant was designed to separate the slag produced at Eastman into 3 usable products. The coarse frit has been shown to be suitable for use as clinker feed for producing Portland cement. The intermediate-size product is enriched in carbon (58-62% C) and may be used as recycle fuel either in the gasifier or in a PC boiler. The fines product contains 30-40% C and may also be used as a recycle gasifier fuel, as is presently done at TECO's Polk Station, however, due to gasifier operating requirements for the production of syngas, this is not feasible at Eastman

Foramen caróticoclinoideo en cráneos humanos: incidencia, morfometría y sus implicaciones clínicas

The caroticoclinoid foramen is an inconstant structure, formed by the union of the anterior and middle clinoid processes. The aim of this study was to perform an incidence and morphometry of the caroticoclinoid foramen in Brazilian human skulls and discuss its clinical implications. Eighty dry human skulls with sex distinction were used, and 3 groups of incidence were determined: General, sex, and sides. The morphometry was performed using a manual caliper and the major diameter of the foramina was measured; the values were also divided in general, according to sex and sides. The incidence of skulls with at least one foramen was 8.5%. According to the sides, 8.5% of the skulls showed foramen on the right side and 2.5% on the left. We found 2.5% of the skulls with bilateral foramen and 6.25% with unilateral foramen. In relation to sex, the foramens were found in 5% of male skulls and 12.5% of female skulls. The major diameter of this structure presented on mean, values of 5.23 mm on general, 5.18 mm on the right side and 5.35 mm on the left, 5.30 mm in male skulls and 5.18 mm in female skulls. The anatomical characteristics of this foramen should be considered in view of its clinical implications associated with neurosurgery as clinoid process removal, and symptoms as headache due to internal carotid artery alterations in this region. In conclusion knowledge of this structure supports the diagnosis and treatment of clinical complications related to this variation.The caroticoclinoid foramen is an inconstant structure, formed by the union of the anterior and middle clinoid processes. The aim of this study was to perform an incidence and morphometry of the caroticoclinoid foramen in Brazilian human skulls and discuss its clinical implications. Eighty dry human skulls with sex distinction were used, and 3 groups of incidence were determined: General, sex, and sides. The morphometry was performed using a manual caliper and the major diameter of the foramina was measured; the values were also divided in general, according to sex and sides. The incidence of skulls with at least one foramen was 8.5%. According to the sides, 8.5% of the skulls showed foramen on the right side and 2.5% on the left. We found 2.5% of the skulls with bilateral foramen and 6.25% with unilateral foramen. In relation to sex, the foramens were found in 5% of male skulls and 12.5% of female skulls. The major diameter of this structure presented on mean, values of 5.23 mm on general, 5.18 mm on the right side and 5.35 mm on the left, 5.30 mm in male skulls and 5.18 mm in female skulls. The anatomical characteristics of this foramen should be considered in view of its clinical implications associated with neurosurgery as clinoid process removal, and symptoms as headache due to internal carotid artery alterations in this region. In conclusion knowledge of this structure supports the diagnosis and treatment of clinical complications related to this variation292427431Das, S., Suri, R., Kapur, V., Ossification of caroticoclinoid ligament and its clinical importance in skull-based surgery (2007) São Paulo Med. J, 125, pp. 351-353Dodo, Y., Ishida, H., Incidence of nonmetric cranial variant in several population samples from East Asia and North America (1987) J. Anthrop. Soc. Nippon, 95, pp. 161-167Dolenc, V.V., A combined epi and subdural direct approach to carotidophthalmic artery aneurysms (1985) J. Neurosurg, 5, pp. 667-672Donald, P.J., (1998) Surgery of the Skull Base, , Philadelphia, Lippincott- RavenErturk, M., Kayalioglu, G., Govsa, F., Anatomy of the clinoidal region with special emphasis on the caroticoclinoid foramen and interclinoid osseous brid- ge in a recent Turkish population (2004) Neurosurg. Rev, pp. 22-26Gupta, N., Ray, B., Ghosh, S., A study on anterior clinoid process and optic strut with emphasis on variations of caroticoclinoid foramen (2005) Nep. Med. Coll. J, 7, pp. 140-144Hochstetter, F., Über die Taenia interclinoidea,die Commissura alicochlearis und die Cartilago supracochlearis des menschlichen Primordialkraniums.Gegenbaurs Morph (1940) Jahrb, 84, pp. 220-243Inoue, T., Rhoton Jr., A.L., Theele, D., Barry, M.E., Surgical approaches to the cavernous sinus:A microsurgical study (1990) Neurosurg, 6, pp. 903-932Kier, E.L., Embryology of the normal optic canal and its anomalies.An anatomic and roentgenographic stud (1966) Invest. Radiol, 1, pp. 346-362Kobayashi, S., Kyoshima, K., Gibo, H., Hedge, S.A., Takemae, T., Sugita, K., Carotid cave aneurysms of the internal carotid artery (1989) J. Neurosurg, 70, p. 216Lee, H.Y., Chung, I.H., Choi B., Y., Anterior, C., (1997) Yonsei Med. J, 38, pp. 151-154Narolewski, R., Significance of anatomic variants of bony surroundings of the internal carotid artery and their significance for lateral surgical approaches to the cavernous sinus (2003) Ann. Acad. Med. Stetin, 49, pp. 205-229Saka, E., Ozdoǧmus, O., Tulay, C., Gürdal, E., Uzün, I., The anatomy of the carotico-clinoid foramen and its relation with the internal carotid artery (2003) Surg. Radiol. Anat, 25, pp. 241-246Reisch, R., Vutskits, L., Filippi, R., Patonay, L., Fries, G., Perneczky, A., Topographic microsurgical anatomy of the paraclinoid carotid artery (2002) Neurosurg Rev, 25, pp. 177-183Sekhar, L.N., Akin, O., Anatomical study of the cavernous sinus emphasizing operative approaches and related vascular and neural reconstruction (1987) Neurosurg, 21, pp. 806-816Seoane, E., Rhoton, A.L., Oliveira, E., Microsurgical anatomy of the dural collar (carotid collar) and rings around the clinoid segment of the internal carotid artery (1998) Neurosurg, 42, pp. 869-886Sicher, H., du Brul, E.L., (1977) Oral Anatomy, , 6ed. Rio de Janeiro, Guanabara KooganStandring, S., Overview of the Development of the Head and Neck Head: Skull and Mandible Gray's anatomy: The anatomical basis of clinical practice, p. 2005. , New York, ElsevierEl foramen caróticoclinoideo es una estructura inconstante formada por la unión de la procesos clinoides anterior y medio. El objetivo de este estudio fue revisar la incidencia y la morfometría del foramen caróticoclinoideo en cráneos humanos brasileños y discutir sus implicaciones clínicas. Se utilizaron 80 cráneos humanos secos, de ambos sexos, determinando tres variables: sexo y lados derecho e izquierdo. La morfometría se realizó con un cáliper manual midiéndose el diámetro máximo del foramen. La incidencia de cráneos con al menos un foramen fue de 8,5%. El 8,5% de los cráneos presentó un foramen en el lado derecho y el 2,5% en el izquierdo. El 2,5% de los cráneos presentó un foramen bilateral y el 6,25% un foramen unilateral. En relación al sexo, los forámenes se encontraron en el 5% de los cráneos de hombres y el 12,5% de los cráneos de mujeres. El diámetro máximo de esta estructura presentó en promedio, valores de 5,23 mm; 5,18 mm en el lado derecho y 5,35 mm en el izquierdo; 5,30 mm en cráneos de hombres y 5.18 mm en cráneos de mujeres. Las características anatómicas de este foramen deben ser consideradas debido a las implicaciones clínicas asociadas a la neurocirugía, como la eliminación del proceso clinoides y a síntomas como cefaleas producto de alteraciones en la arteria carótida interna en esta región. En conclusión, el conocimiento de esta estructura mejora el diagnóstico y tratamiento de las complicaciones clínicas relacionadas con esta variació

Estimating soil carbon content using easily obtainable parameters.

Introduction Among the many strategies adopted to mitigate climate change is the reduction of atmospheric carbon in a process called carbon sequestration, which consists of the transfer of carbon dioxide from the atmosphere to other global pools, such as the soil [1]. Therefore, quantifying the soil carbon is of great importance for successfully measuring the efficiency of carbon sequestration practices and providing accurate reports [2]. The correct measurement of soil carbon is a costly and cumbersome process requiring shipping of samples from the field to laboratories, greatly limiting its applicability [3]. In order to reduce the cost and time required for analyses, several techniques have been developed, such as laser-induced breakdown spectroscopy [4] and online visible and near-infrared spectroscopy with random forests [5]. Even though these new techniques are faster and less expensive, samples still are required to be collected in the field. Developing a method that could provide estimates of the carbon content of farms, using easily obtained variables such as soil texture and practices, would contribute to understanding the relationship between these variables and soil carbon, facilitating carbon sequestration initiatives [6]. Thus, the aim of this project was to train a model on the data available and verify its validity

Comparative study of hydrotalcite-derived supported Pd₂Ga and PdZn intermetallic nanoparticles as methanol synthesis and methanol steam reforming catalysts

An effective and versatile synthetic approach to produce well-dispersed supported intermetallic nanoparticles is presented that allows a comparative study of the catalytic properties of different intermetallic phases while minimizing the influence of differences in preparation history. Supported PdZn, Pd2Ga, and Pd catalysts were synthesized by reductive decomposition of ternary Hydrotalcite-like compounds obtained by co-precipitation from aqueous solutions. The precursors and resulting catalysts were characterized by HRTEM, XRD, XAS, and CO-IR spectroscopy. The Pd2+ cations were found to be at least partially incorporated into the cationic slabs of the precursor. Full incorporation was confirmed for the PdZnAl-Hydrotalcite-like precursor. After reduction of Ga- and Zn-containing precursors, the intermetallic compounds Pd2Ga and PdZn were present in the form of nanoparticles with an average diameter of 6 nm or less. Tests of catalytic performance in methanol steam reforming and methanol synthesis from CO2 have shown that the presence of Zn and Ga improves the selectivity to CO2 and methanol, respectively. The catalysts containing intermetallic compounds were 100 and 200 times, respectively, more active for methanol synthesis than the monometallic Pd catalyst. The beneficial effect of Ga in the active phase was found to be more pronounced in methanol synthesis compared with steam reforming of methanol, which is likely related to insufficient stability of the reduced Ga species in the more oxidizing feed of the latter reaction. Although the intermetallic catalysts were in general less active than a Cu-/ZnO-based material prepared by a similar procedure, the marked changes in Pd reactivity upon formation of intermetallic compounds and to study the tunability of Pd-based catalysts for different reactions