Bioinsecticide-predator interactions: azadirachtin behavioral and reproductive impairment of the coconut mite predator Neoseiulus baraki.

Science.gov (United States)

Lima, Debora B; Melo, José Wagner S; Guedes, Nelsa Maria P; Gontijo, Lessando M; Guedes, Raul Narciso C; Gondim, Manoel Guedes C

2015-01-01

Synthetic pesticide use has been the dominant form of pest control since the 1940s. However, biopesticides are emerging as sustainable pest control alternatives, with prevailing use in organic agricultural production systems. Foremost among botanical biopesticides is the limonoid azadirachtin, whose perceived environmental safety has come under debate and scrutiny in recent years. Coconut production, particularly organic coconut production, is one of the agricultural systems in which azadirachtin is used as a primary method of pest control for the management of the invasive coconut mite, Aceria guerreronis Keifer (Acari: Eriophyidae). The management of this mite species also greatly benefits from predation by Neoseiulus baraki (Athias-Henriot) (Acari: Phytoseiidae). Here, we assessed the potential behavioral impacts of azadirachtin on the coconut mite predator, N. baraki. We explored the effects of this biopesticide on overall predator activity, female searching time, and mating behavior and fecundity. Azadirachtin impairs the overall activity of the predator, reducing it to nearly half; however, female searching was not affected. In contrast, mating behavior was compromised by azadirachtin exposure particularly when male predators were exposed to the biopesticide. Consequently, predator fecundity was also compromised by azadirachtin, furthering doubts about its environmental safety and selectivity towards biological control agents.

Resistance to Wheat Curl Mite in Arthropod-Resistant Rye-Wheat Translocation Lines

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Lina Maria Aguirre-Rojas

2017-11-01

Full Text Available The wheat curl mite, Aceria toschiella (Keifer, and a complex of viruses vectored by A. toschiella substantially reduce wheat yields in every wheat-producing continent in the world. The development of A. toschiella-resistant wheat cultivars is a proven economically and ecologically viable method of controlling this pest. This study assessed A. toschiella resistance in wheat genotypes containing the H13, H21, H25, H26, H18 and Hdic genes for resistance to the Hessian fly, Mayetiola destructor (Say and in 94M370 wheat, which contains the Dn7 gene for resistance to the Russian wheat aphid, Diuraphis noxia (Kurdjumov. A. toschiella populations produced on plants containing Dn7 and H21 were significantly lower than those on plants of the susceptible control and no different than those on the resistant control. Dn7 resistance to D. noxia and H21 resistance to M. destructor resulted from translocations of chromatin from rye into wheat (H21—2BS/2RL, Dn7—1BL/1RS. These results provide new wheat pest management information, indicating that Dn7 and H21 constitute resources that can be used to reduce yield losses caused by A. toschiella, M. destructor, D. noxia, and wheat streak mosaic virus infection by transferring multi-pest resistance to single sources of germplasm.

Estimated crop loss due to coconut mite and financial analysis of controlling the pest using the acaricide abamectin.

Science.gov (United States)

Rezende, Daniela; Melo, José W S; Oliveira, José E M; Gondim, Manoel G C

2016-07-01

Reducing the losses caused by Aceria guerreronis Keifer has been an arduous task for farmers. However, there are no detailed studies on losses that simultaneously analyse correlated parameters, and very few studies that address the economic viability of chemical control, the main strategy for managing this pest. In this study the objectives were (1) to estimate the crop loss due to coconut mite and (2) to perform a financial analysis of acaricide application to control the pest. For this, the following parameters were evaluated: number and weight of fruits, liquid albumen volume, and market destination of plants with and without monthly abamectin spraying (three harvests). The costs involved in the chemical control of A. guerreronis were also quantified. Higher A. guerreronis incidence on plants resulted in a 60 % decrease in the mean number of fruits harvested per bunch and a 28 % decrease in liquid albumen volume. Mean fruit weight remained unaffected. The market destination of the harvested fruit was also affected by higher A. guerreronis incidence. Untreated plants, with higher A. guerreronis infestation intensity, produced a lower proportion of fruit intended for fresh market and higher proportions of non-marketable fruit and fruit intended for industrial processing. Despite the costs involved in controlling A. guerreronis, the difference between the profit from the treated site and the untreated site was 18,123.50 Brazilian Real; this value represents 69.1 % higher profit at the treated site.

Tolerance of the eriophyid mite Aceria salsolae to UV-A light and implications for biological control of Russian thistle.

Science.gov (United States)

Moran, Patrick J; Wibawa, M Irene; Smith, Lincoln

2017-12-01

Aceria salsolae (Acari: Eriophyidae) is being evaluated as a candidate biological control agent of Russian thistle (Salsola tragus, Chenopodiaceae), a major invasive weed of rangelands and dryland crops in the western USA. Prior laboratory host range testing under artificial lighting indicated reproduction on non-native Bassia hyssopifolia and on a native plant, Suaeda calceoliformis. However, in field tests in the native range, mite populations released on these 'nontarget' plants remained low. We hypothesized that UV-A light, which can affect behavior of tetranychid mites, would affect populations of the eriophyid A. salsolae differently on the target and nontarget plant species, decreasing the mite's realized host range. Plants were infested with A. salsolae under lamps that emitted UV-A, along with broad-spectrum lighting, and the size of mite populations and plant growth was compared to infested plants exposed only to broad-spectrum light. Russian thistle supported 3- to 55-fold larger mite populations than nontarget plants regardless of UV-A treatment. UV-A exposure did not affect mite populations on Russian thistle or S. calceoliformis, whereas it increased populations 7-fold on B. hyssopifolia. Main stems on nontarget plants grew 2- to 6-fold faster than did Russian thistle under either light treatment. The two nontarget plants attained greater volume under the control light regime than UV-A, but Russian thistle was unaffected. Although Russian thistle was always the superior host, addition of UV-A light to the artificial lighting regime did not reduce the ability of A. salsolae to reproduce on the two nontarget species, suggesting that UV-B or other environmental factors may be more important in limiting mite populations in the field.

Behaviour of coconut mites preceding take-off to passive aerial dispersal.

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Melo, J W S; Lima, D B; Sabelis, M W; Pallini, A; Gondim, M G C

2014-12-01

For more than three decades the coconut mite Aceria guerreronis Keifer is one of the most important pests of coconut palms and has recently spread to many coconut production areas worldwide. Colonization of coconut palms is thought to arise from mites dispersing aerially after take-off from other plants within the same plantation or other plantations. The underlying dispersal behaviour of the mite at take-off, in the airborne state and after landing is largely unknown and this is essential to understand how they spread from tree to tree. In this article we studied whether take-off to aerial dispersal of coconut mites is preceded by characteristic behaviour, whether there is a correlation between the body position preceding aerial dispersal and the direction of the wind, and whether the substrate (outer surface of coconut bracts or epidermis) and the wind speed matter to the decision to take-off. We found that take-off can sometimes be preceded by a raised body stance, but more frequently take-off occurs while the mite is walking or resting on its substrate. Coconut mites that become airborne assumed a body stance that had no relation to the wind direction. Take-off was suppressed on a substrate providing food to coconut mites, but occurred significantly more frequently on the outer surface of coconut bracts than on the surface of the fruit. For both substrates, take-off frequency increased with wind speed. We conclude that coconut mites have at least some degree of control over take-off for aerial dispersal and that there is as yet no reason to infer that a raised body stance is necessary to become airborne.

Limits to ambulatory displacement of coconut mites in absence and presence of food-related cues.

Science.gov (United States)

Melo, J W S; Lima, D B; Sabelis, M W; Pallini, A; Gondim, M G C

2014-04-01

Ambulatory movement of plant-feeding mites sets limits to the distances they can cover to reach a new food source. In absence of food-related cues these limits are determined by survival, walking activity, walking path tortuosity and walking speed, whereas in presence of food the limits are also determined by the ability to orient and direct the path towards the food source location. For eriophyoid mites such limits are even more severe because they are among the smallest mites on earth, because they have only two pairs of legs and because they are very sensitive to desiccation. In this article we test how coconut mites (Aceria guerreronis Keifer) are constrained in their effective displacement by their ability to survive in absence of food (meristematic tissue under the coconut perianth) and by their ability to walk and orient in absence or presence of food-related cues. We found that the mean survival time decreased with increasing temperature and decreasing humidity. Under climatic conditions representative for the Tropics (27 °C and 75 % relative humidity) coconut mites survived on average for 11 h and covered 0.4 m, representing the effective linear displacement away from the origin. Within a period of 5 h, coconut mites collected from old fruits outside the perianth moved further away from the origin than mites collected under the perianth of young fruits. However, in the presence of food-related cues coconut mites traveled over 30 % larger distances than in absence of these cues. These results show that ambulatory movement of eriophyoid mites may well bring them to other coconuts within the same bunch and perhaps also to other bunches on the same coconut palm, but it is unlikely to help them move from palm to palm, given that palms usually do not touch each other.

Size of predatory mites and refuge entrance determine success of biological control of the coconut mite

NARCIS (Netherlands)

da Silva, F.R.; de Moraes, G.J.; Lesna, I.; Sato, Y.; Vasquez, C.; Hanna, R.; Sabelis, M.W.; Janssen, A.

2016-01-01

Predators face the challenge of accessing prey that live in sheltered habitats. The coconut mite Aceriaguerreronis Keifer (Acari: Eriophyidae) lives hidden beneath the perianth, which is appressed to the coconut fruit surface, where they feed on the meristematic tissue. Its natural enemy, the

Effects of Clone, Silvicultural, and Miticide Treatments on Cottonwood Leafcurl Mite (Acari: Eriophyidae) Damage in Plantation Populus

Science.gov (United States)

David R. Coyle

2002-01-01

Aculops lobuliferus (Keifer) is a little known pest of plantation Populus spp., which is capable of causing substantial damage. This is the First documented occurrence of A. lobuliferus in South Carolina. Previous anecdotal data indicated clonal variation in Populus susceptibility to A...

Research Article Special Issue

African Journals Online (AJOL)

2017-10-05

Oct 5, 2017 ... N-560) and portable finger pulse oximeter (OLED SPO2). ... This study received ethical approval from the institution review board .... [18] MacLeod D B, Cortinez L I, Keifer J C, Cameron D, Wright D R, White W D, Moretti E.

Below-ground plant parts emit herbivore-induced volatiles: olfactory responses of a predatory mite to tulip bulbs infested by rust mites

NARCIS (Netherlands)

Aratchige, N.S.; Lesna, I.; Sabelis, M.W.

2004-01-01

Although odour-mediated interactions among plants, spider mites and predatory mites have been extensively studied above-ground, belowground studies are in their infancy. In this paper, we investigate whether feeding by rust mites (Aceria tulipae) cause tulip bulbs to produce odours that attract

CARACTERIZACIÓN DE POLVOS DE ACERÍA ELÉCTRICA PRODUCIDOS EN VENEZUELA Y EVALUACIÓN PRELIMINAR DE SU LIXIVIABILIDAD CON ÁCIDOS ORGÁNICOS DILUIDOS

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PEDRO DELVASTO

2011-01-01

Full Text Available Se estudiaron polvos de aceria cuyo analisis quimico revelo un contenido (en peso de: 27,0 % de Fe; 7,1 % de Mg; 4,9 % de Zn; 4,0 % de Ca y 0,5 % de Pb. La difraccion de rayos X y la espectroscopia infrarroja, permitio identificar en los polvos las siguientes fases: espinelas, Fe3O4, CaCO3, SiO2, ZnO y PbO. El analisis microscopico de estos residuos indico que estan formados por agregados de particulas esferoidales cuyo tamano varia entre 120 y 0,25 ¿Êm. La lixiviabilidad de los mismos se evaluo durante 28 dias en columnas de percolacion, empleando agua y disoluciones de acidos organicos como agentes lixiviantes. El objetivo fue evaluar el comportamiento del residuo bajo condiciones similares a las que generan los microorganismos naturales del suelo. Se encontro que la lixiviabilidad de Zn y Pb vario entre 80 y 16 mg mensuales por kilogramo de polvo de aceria.

Generic delimitation between Fragariocoptes and Sierraphytoptus (Acari: Eriophyoidea: Phytoptidae) and a supplementary description of Fragariocoptes gansuensis with remarks on searching for mummified eriophyoid mites in herbaria under UV light.

Science.gov (United States)

Chetverikov, Philipp E

2016-01-15

Generic concepts of Fragariocoptes Roivainen, 1951 and Sierraphytoptus Keifer, 1939 are discussed and the correct delimitation between these two genera is given. A supplementary description of Fragariocoptes gansuensis Wei, Chen & Luo, 2005 is included based on fresh specimens from Astrakhan, Russia and dried mummies found in old herbaria collected in 1919 from southern European Russia of the cinquefoil, Potentilla bifurca L. (Rosaceae) with pathological stem proliferation. The male of this species is described for the first time. The cuticle of eriophyoid mummies emitted a faint glow under UV light wavelength equal to 365 nm of a common UV Light-Emitting diode (LED) lamp showing that this characteristic could be useful for quickly detecting eriophyoids in old herbaria which would otherwise be almost indistinguishable against the background under the regular white light source of a stereomicroscope. This was only possible for plant material stored in appropriate conditions enabling the autofluorescent signal of the dried mite cuticle to remain strong enough for observation.

Below-ground plant parts emit herbivore-induced volatiles: olfactory responses of a predatory mite to tulip bulbs infested by rust mites.

Science.gov (United States)

Aratchige, N S; Lesna, I; Sabelis, M W

2004-01-01

Although odour-mediated interactions among plants, spider mites and predatory mites have been extensively studied above-ground, belowground studies are in their infancy. In this paper, we investigate whether feeding by rust mites (Aceria tulipae) cause tulip bulbs to produce odours that attract predatory mites (Neoseiulus cucumeris). Since our aim was to demonstrate such odours and not their relevance under soil conditions, the experiments were carried out using a classic Y-tube olfactometer in which the predators moved on a Y-shaped wire in open air. We found that food-deprived female predators can discriminate between odours from infested bulbs and odours from uninfested bulbs or artificially wounded bulbs. No significant difference in attractiveness to predators was found between clean bulbs and bulbs either wounded 30 min or 3 h before the experiment. These results indicate that it may not be simply the wounding of the bulbs, but rather the feeding by rust mites, which causes the bulb to release odours that attract N. cucumeris. Since bulbs are belowground plant structures, the olfactometer results demonstrate the potential for odour-mediated interactions in the soil. However, their importance in the actual soil medium remains to be demonstrated.

Observações sôbre o bronzeado do algodoeiro Mocó Observations on bronzing of the Mocó cotton

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A. S. Costa

1955-01-01

Full Text Available Uma anomalia do algodoeiro Mocó, denominada bronzeado, vem sendo observada na região do Seridó, Rio Grande do Norte, durante os últimos três anos. Pensou-se, a princípio, que esta anomalia fôsse causada por um vírus, mas as observações relatadas neste trabalho indicam que é causada por um ácaro. As fôlhas das plantas afetadas, especialmente aquelas da metade superior dos galhos, mostram uma coloração bronzeada no lado de baixo. Essa face da fôlha tem também uma superfície rugosa, com brilho vidrado (est. 1, B, as vezes com pequenas áreas de tecido cicatricial. Vistas pelo lado de cima são mais rugosas do que as normais e têm os bordos curvados para baixo. Nos casos graves, as fôlhas do topo dos galhos morrem e caem (est. 2, A e B. A espécie de ácaro causadora do bronzeado do algodoeiro Mocó foi identificada por H. H. Keifer, Sacramento, Calif., como pertencente a um gênero ainda não descrito da família Eriophyidae. Esta espécie está sendo presentemente denominada Anthocoptes sp. até que a sua descrição seja publicada. Populações de 500 a 1.000 indivíduos por centímetro quadrado de fôlha já foram encontradas. Esse ácaro parece ser muito sensível às condições do ambiente, visto que as populações da praga variam entre grandes limites.For the last three years a bronzing anomaly of cotton plants of the Mocó variety (Gossypium hirsutum L. var. maria galante Hutch. has been recorded in the Seridó region (a semi-arid region in the north-eastern part of Brazil, state of Rio Grande do Norte. This anomaly was first thought to be of virus origin, but the observations reported in this paper indicated that it is due to the attack by a species of mite. Leaves from affected plants, especially those on the upper half of the branches, show a bronzing discoloration on the dorsal side, frequently accompanied by a rough and ventral side of these leaves shows some rugosity not present in normal leaves, and in most cases

Volatile Metabolomic Composition of Vitex Species: Chemodiversity Insights and Acaricidal Activity

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José G. de Sena Filho

2017-11-01

Full Text Available The Vitex genus (Lamiaceae produces a plethora of metabolites that include ecdysteroids and terpenoids, some of which have demonstrated insect repellent properties. The volatile composition of several members of this genus has not been chemically defined, as many taxa are endemic to remote ecosystems. In this study, leaves were collected from the northeast of Brazil from Vitex capitata, V. megapotamica, V. gardneriana, and V. rufescens plants and examined for their chemical profile via GC-MS/FID of essential oil extracts. The analyses showed a diversity of terpenoids. Of particular note were seven-member ring sesquiterpenes which were present in great abundance; a dendrogram showed clades separating by the production of bicyclogermacrene, aromadendrane and 5,10-cycloaromadendrane sesquiterpenoids for the four species. Comparison of volatile metabolite profiles to 13 other Vitex species showed strong similarities in the production of some monoterpenes, but varied by their production of larger terpenes, especially those with gem-dimethylcyclopropyl subunits on seven-member ring compounds. From this work, we suggest that the sesquiterpene skeleton with seven member rings is a good chemosystematic biomarker candidate for the Vitex genus. Separation using this biomarker was then validated using Inter-Simple Sequence Repeat profiling. Lastly, experiments examining the toxicity of these four oils against the coconut mite Aceria guerreronis showed that only the oil of V. gardneriana had strong acaricidal activity, with an LC50 of 0.85 mg/mL, thus demonstrating its potential for use as a natural pesticide.

Population-level effects of abamectin, azadirachtin and fenpyroximate on the predatory mite Neoseiulus baraki.

Science.gov (United States)

Lima, Debora B; Melo, José W S; Gondim, Manoel G C; Guedes, Raul N C; Oliveira, José E M

2016-10-01

The coconut production system, in which the coconut mite Aceria guerreronis is considered a key pest, provides an interesting model for integration of biological and chemical control. In Brazil, the most promising biological control agent for the coconut mite is the phytoseiid predator Neoseiulus baraki. However, acaricides are widely used to control the coconut mite, although they frequently produce unsatisfactory results. In this study, we evaluated the simultaneous direct effect of dry residue contact and contaminated prey ingestion of the main acaricides used on coconut palms (i.e., abamectin, azadirachtin and fenpyroximate) on life-history traits of N. baraki and their offspring. These acaricides are registered, recommended and widely used against A. guerreronis in Brazil, and they were tested at their label rates. The offspring of the exposed predators was also evaluated by estimating the instantaneous rate of population increase (r i ). Abamectin compromised female performance, whereas fenpyroximate did not affect the exposed females (F0). Nonetheless, fenpyroximate strongly compromised the offspring (F1) net reproductive rate (R0), intrinsic rate of population growth (r i ), and doubling time (DT). In contrast, fenpyroximate did not have such effects on the 2nd generation (F2) of predators with acaricide-exposed grandparents. Azadirachtin did not affect the predators, suggesting that this acaricide can be used in association with biological control by this predatory species. In contrast, the use of abamectin and fenpyroximate is likely to lead to adverse consequences in the biological control of A. guerreronis using N. baraki.

[Risk assessment and control strategies of pests in Lycium barbarum fields under different managements].

Science.gov (United States)

Zhao, Zi-Hua; Zhang, Rong; He, Da-Han; Wang, Fang; Zhang, Ting-Ting; Zhang, Zong-Shan

2009-04-01

In the risk assessment of pests, both the community structure and the environmental factors should be considered at the same time, because of their mutual effects on the outbreak of disaster pests. This paper established a comprehensive assessment system, including 2 sub-systems, 5 respects, and 14 indices. In the meanwhile, risk assessment indices and experience formula were used to analyze the risk degree of pests in Lycium barbarum fields under different managements. It was found that using risk assessment indices and experience formula could obtain similar results. In abandoned field, Aceria palida, Aphis sp., and Paratrioza sinica were the frequent disaster pests, Lema decempunctata, Neoceratitis asiatica, Jaapiella sp., and Phthorimaea sp. were the incidental disaster pests, and Psylliodes obscurofaciata and Phthorimaea sp. were general pests. In organic field, the frequent disaster pests were the same species as those in abandoned field, while P. indicus, Jaapiella sp. and Phthorimaea sp. were the incidental disaster pests. In chemical control field, A. palida, Aphis sp., P. sinica, and P. indicus were the frequent disaster pests, while Jaapiella sp. and Phthorimaea sp. were the incidental disaster pests. Optimal 5 separations most fitted the division of pest sub-communities in L. barbarum fields, which were infancy period (from March 28 to April 15), outbreak I period (from April 15 to July 18), dormancy period (from July 18 to September 8), outbreak II period (from September 8 to October 15), and recession period (after October 15). The matrix of correlation coefficient showed that the dynamics of pests in L. barbarum fields under different managements were significantly correlated with each other, suggesting that the dynamics of pest populations was similar in different L. barbarum fields, which had two population establishment stages and one exponential growth stage in every year. The optimal controlling stages were from late infancy period to early and

Obtaining a glass-ceramic material from a steel slag mixed with glass cullet; Obtencion de un material vitroceramico a partir de una escoria de aceria mezclada con vidrio de desecho

Energy Technology Data Exchange (ETDEWEB)

Oziel Mendez Guerrero, D.; Alicia Vazquez Mendez, B.; Alvarez Mendez, A.

2011-07-01

In this paper, the qualitative, quantitative and thermal characterization of a steel slag and glass cullet of high generation rate in northern Mexico were made in order to use these wastes as raw materials in the production of glass ceramics. The particle size was controlled at sizes = 75 micrometers and the major components of the slag were located in a phase equilibrium diagram for proposing a reaction temperature that leaded to the starting glass. Later, heat treatments were performed to obtain the glass ceramics. The materials were characterized by powder X-ray diffraction (XRD), differential thermal analysis coupled with thermal gravimetric analysis (DTA-TGA), reflected light optical microscopy (RLOM) and scanning electron microscopy (SEM). Subsequently, Vickers microhardness and chemical resistance tests were performed, which enabled us to propose an application of the glass ceramics. (Author) 18 refs.

Experiences on modernization of steel production plants in countries which metallurgy industry is in reconversion process; Experiencias en la modernizacion de acerias en paises en reconversion de su industria siderurgica

Energy Technology Data Exchange (ETDEWEB)

Palacios, Jose M. [Bilbao Univ. (Spain). Escuela Tecnica Superior de Ingenieros Industriales; Munoz, Jon

1986-12-31

The Spanish experience on modernization of its metal industry, mainly steel production sector, under a strong structural exchange, face the Europe Common Market and the metal industry crisis are discussed. Economical and technological aspects of those exchanges, the measures applied, development of new technologies, innovations presented on the sector of electric arc furnace, increase of productivity, main steps present on modern steel production sector, are also analysed. 7 figs., 5 tabs., 7 refs

Neoseiulus paspalivorus, a predator from coconut, as a candidate for controlling dry bulb mites infesting stored tulip bulbs.

Science.gov (United States)

Lesna, Izabela; da Silva, Fernando R; Sato, Yukie; Sabelis, Maurice W; Lommen, Suzanne T E

2014-06-01

The dry bulb mite, Aceria tulipae, is the most important pest of stored tulip bulbs in The Netherlands. This tiny, eriophyoid mite hides in the narrow space between scales in the interior of the bulb. To achieve biological control of this hidden pest, candidate predators small enough to move in between the bulb scales are required. Earlier experiments have shown this potential for the phytoseiid mite, Neoseiulus cucumeris, but only after the bulbs were exposed to ethylene, a plant hormone that causes a slight increase in the distance between tulip bulb scales, just sufficient to allow this predator to reach the interior part of the bulb. Applying ethylene, however, is not an option in practice because it causes malformation of tulip flowers. In fact, to prevent this cosmetic damage, bulb growers ventilate rooms where tulip bulbs are stored, thereby removing ethylene produced by the bulbs (e.g. in response to mite or fungus infestation). Recently, studies on the role of predatory mites in controlling another eriophyoid mite on coconuts led to the discovery of an exceptionally small phytoseiid mite, Neoseiulus paspalivorus. This predator is able to move under the perianth of coconuts where coconut mites feed on meristematic tissue of the fruit. This discovery prompted us to test N. paspalivorus for its ability to control A. tulipae on tulip bulbs under storage conditions (ventilated rooms with bulbs in open boxes; 23 °C; storage period June-October). Using destructive sampling we monitored predator and prey populations in two series of replicated experiments, one at a high initial level of dry bulb mite infestation, late in the storage period, and another at a low initial dry bulb mite infestation, halfway the storage period. The first and the second series involved treatment with N. paspalivorus and a control experiment, but the second series had an additional treatment in which the predator N. cucumeris was released. Taking the two series of experiments together

Methodology for the characterization and radioactive tracing of a reference to the control of radioactive material in steel mills; Metodologia para la caracterizacion y trazado radiactivo de un material de referencia para el control radiactivo en acerias

Energy Technology Data Exchange (ETDEWEB)

Mejuto Mendieta, M.; Crespo Vazquez, M. T.; Peyres Medina, V.; Garcia-Torano, E.; Perez del Villar, L.

2013-07-01

One of the tasks which corresponded you to the Laboratory of Metrology of Ionizing Radiation CIEMAT, consists of the preparation of the reference standards of a black slag from steel making drawn {sup 2}26Ra, {sup 1}37Cs, {sup 6}0Co. This work summarizes the steps followed for the preparation of the reference standards of the slag, including the physical sample preparation, chemical, mineralogical and radioactive characterization as well as the development of the method of path with the above listed radionuclides. (Author)

Fault Control on Copper Depositsin the Sar Cheshmeh Area Indicated by Remote Sensing & Geographic Information Systems (GIS

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Hojjat Ollah Safari

2016-07-01

Full Text Available Introduction The Sar Cheshmeh copper deposit and indications of other deposits are located in the Dehaj-Sarduieh belt in the Kerman region (Khadem and Nedimovic, 1973. This belt is one of the most important provinces of Cu mineralization in Iran, with approximately 300 Cu deposits and prospects, includingtwenty of the porphyry copper type (Ghorbani, 2013. This belt, 300 km in length and 30–45 km width, is situated in the southern part of the Uramia-Dokhtar volcanic belt in central Iran (Shafiei, 2010. Zarasvandi (2004 has proposed that faulting has played a role in the location of copper deposition in this area. Methods of Investigation In order to check Zarasvandi’s hypothesis, the spatial relationship between faults and Cu deposits was investigated using remote sensing and GIS techniques together with field investigations in the Sar Cheshmeh area. The the following steps were used in this research: 1. Review of available data 2. Surface geology field studies 3. Preparation of digital overlay of Copper occurrences 4. Analysis of the relationshipof faulting to Copper occurrences Using remote sensing techniques, a geometrically corrected satellite image was filtered with high pass and Sharpen Edge filters to detect possible lineaments (Lillesand and Keifer, 2008; Sabins, 1996. Directional filters (45º, 90º, 135º and 180º were then applied to the processed image to enhance the linear structures. Subsequently,the major lineaments were documented in the field as major and minor faults (Safari et al., 2011. Four main faults, designated as the Rafsanjan, Mani, Gaud-e-Ahmar and Sar Cheshmeh faultswere determined to be major. These faults were digitized and overlaid on other data layers in GIS environment. The strikes, dips, striae and directions of movementof the faultswere measured at 20 locations in the field. Structural analyses were done with Rose diagrams, calculation of P-axes and preparation of a structural map. Copper occurrences on the

Energy saving in the pig iron production in the blast furnace no. 5; Ahorro de energia en la produccion de arrabio en el alto horno No. 5

Energy Technology Data Exchange (ETDEWEB)

Gil Diaz, Ricardo A; J Quiroz, Francisco; Rodriguez, Rita Patricia; Banuelos Garza, Yolanda [Altos Hornos de Mexico, S. A., Coahuila (Mexico)

1994-12-31

. Summarizing, the modern practices in the use of the auxiliary fuels, implemented in the AHMSA blast furnaces, have derived benefits, succeeding in diminishing the productions costs in the pig iron production process, faced to the true need of standing out in the even more competitive world of iron and steel industry of the world. [Espanol] Altos Hornos de Mexico es una industria siderurgica integrada al Grupo Acereros del Norte, localizada en la ciudad de Monclova Coahuila, contando con una capacidad anual instalada de 3.1 MMT de acero liquido. Dentro de sus instalaciones, AHMSA cuenta con el alto horno de mayor capacidad instalado en Mexico, el alto horno No. 5, el cual tiene un volumen util de 2,163 metros cubicos disenado para producir 4,800 toneladas de arrabio por dia. La meta basica a lograr en las operaciones involucradas en la elaboracion de acero via elaboracion de arrabio en el alto horno, es la produccion de metal caliente al mas bajo costo posible y dentro de los requerimientos de calidad especificado por las acerias. El mas importante criterio para la medicion del exito alcanzado es el consumo de combustible por tonelada de arrabio producida, siendo el coque el principal combustible alimentado al alto horno y por ende el que mayor impacto tiene sobre el costo final del producto. AHMSA contemplo dentro de su plan estrategico, la disminucion de produccion de sus plantas coquizadoras derivadas del envejecimiento natural de sus hornos, consecuencia de esto se hace inminente el deficit de coque para producciones mayores de 2.6 MMT de acero liquido. En respuesta a esto, y ante la verdadera necesidad de disminuir los costos de produccion en el proceso de elaboracion de arrabio, se han implementado nuevas practicas en el uso de los combustibles auxiliares que sustituyan en parte el consumo de coque metalurgico como fuente de energia en el proceso del alto horno. El uso del gas natural, combustoleo y el incremento paulatino de la temperatura de soplo caliente, han

Energy saving in the pig iron production in the blast furnace no. 5; Ahorro de energia en la produccion de arrabio en el alto horno No. 5

Energy Technology Data Exchange (ETDEWEB)

Gil Diaz, Ricardo A.; J Quiroz, Francisco; Rodriguez, Rita Patricia; Banuelos Garza, Yolanda [Altos Hornos de Mexico, S. A., Coahuila (Mexico)

1993-12-31

. Summarizing, the modern practices in the use of the auxiliary fuels, implemented in the AHMSA blast furnaces, have derived benefits, succeeding in diminishing the productions costs in the pig iron production process, faced to the true need of standing out in the even more competitive world of iron and steel industry of the world. [Espanol] Altos Hornos de Mexico es una industria siderurgica integrada al Grupo Acereros del Norte, localizada en la ciudad de Monclova Coahuila, contando con una capacidad anual instalada de 3.1 MMT de acero liquido. Dentro de sus instalaciones, AHMSA cuenta con el alto horno de mayor capacidad instalado en Mexico, el alto horno No. 5, el cual tiene un volumen util de 2,163 metros cubicos disenado para producir 4,800 toneladas de arrabio por dia. La meta basica a lograr en las operaciones involucradas en la elaboracion de acero via elaboracion de arrabio en el alto horno, es la produccion de metal caliente al mas bajo costo posible y dentro de los requerimientos de calidad especificado por las acerias. El mas importante criterio para la medicion del exito alcanzado es el consumo de combustible por tonelada de arrabio producida, siendo el coque el principal combustible alimentado al alto horno y por ende el que mayor impacto tiene sobre el costo final del producto. AHMSA contemplo dentro de su plan estrategico, la disminucion de produccion de sus plantas coquizadoras derivadas del envejecimiento natural de sus hornos, consecuencia de esto se hace inminente el deficit de coque para producciones mayores de 2.6 MMT de acero liquido. En respuesta a esto, y ante la verdadera necesidad de disminuir los costos de produccion en el proceso de elaboracion de arrabio, se han implementado nuevas practicas en el uso de los combustibles auxiliares que sustituyan en parte el consumo de coque metalurgico como fuente de energia en el proceso del alto horno. El uso del gas natural, combustoleo y el incremento paulatino de la temperatura de soplo caliente, han