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1.
Arq. Inst. Biol. (Online) ; 89: e00202020, 2022. tab
Article in English | LILACS, VETINDEX | ID: biblio-1416770

ABSTRACT

The evaluated ammonia volatilization rates and its association with humidity, temperature, and pH in broiler litter in conventional and dark house rearing systems. Evaluations were performed at 0.01, 1.00, and 1.50 m high, using a completely randomized design, at a weekly frequency for 12 weeks­from the sanitary void to the end of the 42-day cycle. Litter temperature had no significant difference for different types of house. Humidity and pH levels varied according to houses and evaluation periods. No ammonia volatilization was detected during initial periods. However, up from the 21st day of rearing, rates started to increase, showing higher concentrations at 0.01 m height. At 1.00 and 1.50 m, values around 20 mL·m­3, were obtained and considered an acceptable exposure level for the broilers and employees directly working in this sector. Yet, broiler breeders should target lower levels due to environmental impacts.


Subject(s)
Animals , Volatilization , Chickens , Inhalation Exposure/analysis , Ammonia/pharmacokinetics , Occupational Health Services
2.
Biosci. j. (Online) ; 32(1): 108-114, jan./fev. 2016. tab
Article in English | LILACS | ID: biblio-965254

ABSTRACT

The efficacy of pesticide applications is related to the spread and evaporation time of the droplets deposited on the target. This study evaluates the evaporation of spray droplets containing thiamethoxam and adjuvants on different surfaces and at different levels of relative air humidity. A climate controlled chamber was set up with a digital microscope to produce images of droplet evaporation. Three surfaces (hydrophilic, lipophilic and hydrophobic), five solutions (water, thiamethoxam, thiamethoxam + mineral oil, thiamethoxam + vegetable oil, thiamethoxam + surfactant) and three air humidity levels (45%, 60% and 75%) were evaluated. The surface tension of these solutions was also measured. It was found that all of the insecticide solutions reduced surface tension, that air humidity, target surface and spray formulation influenced spray evaporation and that surfactants reduced the evaporation time of droplets on natural lipophilic surfaces.


A eficácia de uma aplicação de produto fitossanitário está relacionada ao espalhamento e ao tempo de evaporação das gotas depositadas sobre o alvo. O presente trabalho teve como objetivo avaliar a evaporação de gotas depositadas em distintas superfícies, a partir de caldas contendo tiametoxam e adjuvantes, em diferentes umidades relativas do ar. Foi montada uma estrutura a partir de uma câmara climática de condições controladas e um microscópio digital para análise de imagens da evaporação de gotas. Foram avaliadas, em três superfícies (hidrofílica, hidrofóbica e lipofílica), cinco soluções (água, tiametoxam, tiametoxam + óleo mineral, tiametoxam + óleo vegetal, tiametoxam + espalhante) e três umidades relativas do ar (45%, 60% e 75%). Também foi realizada análise da tensão superficial destas soluções. Com base nos resultados obtidos, todas as soluções inseticidas reduziram a tensão superficial da calda; a umidade relativa do ar, a estrutura da superfície alvo e a formulação da calda do produto fitossanitário influenciaram a evaporação de gotas em superfície; e o uso de surfactantes reduziu o tempo de evaporação de gotas depositadas em superfície natural lipofílica.


Subject(s)
Pesticides , Volatilization , Evaporation
3.
Chinese Traditional and Herbal Drugs ; (24): 2650-2655, 2016.
Article in Chinese | WPRIM | ID: wpr-853366

ABSTRACT

Objective: To establish a method for the determination of three main volatile components (menthone, menthol, and pulegone) in Yinqiao Powder (YQP) distillate and provide the evidence for elucidating the scientific connotation of its traditional decocting method "taking when the fragrance volatilized fiercely". Methods: YQP distillates with different decocting time were prepared to study the dynamic changes of chemical components during decocting process. GC-MS was used to analyze the volatile components qualitatively and determine the contents of menthone, menthol, and pulegone in YQP distillate. Results: GC-MS total ion chromatograms of YQP volatile oil included 26 peaks, of which the relative contents of 14 peaks were greater than 1.5%, mainly from Forsythiae Fructus, Menthae Haplocalycis Herba, and Schizonepetae Herba. With the extension of the boiling time, the evaporation rates of menthone, menthol, and pulegone all increased to maximum and then decreased gradually. When boiling for 5-10 min, the maximum average evaporation rates of menthone, menthol, and pulegone were 13.77, 147.74, and 31.26 ìg/min, respectively. When boiling for 0-5, 5-10, 10-15, 15-20, 20-25, 25-30, 30-40, 40-50, 50-60, 60-80, 80-100, and 100-120 min, the average evaporation rates of total three volatile components were 160.23, 192.77, 120.71, 70.85, 54.01, 42.41, 30.36, 17.87, 14.98, 10.01, 7.79, and 7.58 ìg/min, respectively. Conclusion: The evaporation rates of menthone, menthol, and pulegone in YQP are heavily influenced by decocting time. The fragrance is volatilized fiercely at about 5 min after boiling, while the average evaporation rates of menthone, menthol, and pulegone are high, so after boiling for 5-10 min, menthone, menthol, and pulegone were evaporated a lot. The fragrance gets weak after 15 min of boiling, the average evaporation rates of menthone, menthol, and pulegone are decreasing heavily. It is suggested that the traditional decocting method has some scientific foundation.

4.
China Journal of Chinese Materia Medica ; (24): 60-64, 2016.
Article in Chinese | WPRIM | ID: wpr-284743

ABSTRACT

To establish a method for the determination of chemical specific chromatograms and five components in Yinqiao powder decoction, and provide basis for elucidating the scientific connotation of ″taking in when the fragrance volatilized fiercely″. Yinqiao powder decoctions with different decocting times were prepared to study the changes of chemical components during decocting process. Specific chromatograms and contents of chlorogenic acid, phillyrin, arctiin, liquiritin and glycyrrhizin were determined by high performance liquid chromatography. According to the results, the similarities of Yinqiao powder decoctions with different decocting times were high, which indicated that their chemical compositions were similar. The dissolutions of the five components in Yinqiao powder reached more than 39.7% of 2 hour maximum dissolution amounts (MDA) after 20 minutes of soaking, more than 69.5% of MDA when boiling, more than 79.1% of MDA at the 5th minute after boiling, and more than 85.7% of MDA at the 10th minute after boiling. The concentrations of five components were not increasing obviously after 15 minutes of boiling (RSD<4.3%). The fragrance volatilized fiercely at about the 5th minute after boiling, which indicated that the contents of volatile components in Yinqiao powder decoctions were high, but it became weak after boiling for 15 minutes, which indicated that the contents of volatile components in Yinqiao powder decoctions were low. The results showed that the contents of five components in Yinqiao powder decoctions were heavily influenced by the decocting time. When boiling for about 5 minutes, the fragrance volatilized fiercely, both the contents of volatile components and non-volatile components were high. It is suggested that the traditional decocting method has a certain scientific basis.

5.
China Journal of Chinese Materia Medica ; (24): 3349-3354, 2016.
Article in Chinese | WPRIM | ID: wpr-307153

ABSTRACT

To establish a method for the determination of three volatile components: menthone, menthol and pulegone in Yinqiao powder (YQP) decoction, explore the change rules of volatile components in decocting process, and provide evidence for elucidating the scientific connotation of its traditional decocting method "taking when the fragrance is volatilized fiercely". YQP decoctions with different decocting time were prepared, and GC-MS was used to qualitatively analyze the volatile components and determine the contents of menthone, menthol and pulegone in decoctions. Then the effects of different decocting time on contents of volatile components were investigated. The results showed that the volatile components in YQP decoctions mainly come from Menthae Haplocalycis Herba, Schizonepetae Herba and Forsythiae Fructus. With the extension of decocting time, the concentrations of all the above 3 volatile components in Yinqiao powder decoction were first increased and then decreased. When soaking for 30 minutes, as well as boiling for 0, 5, 10, 15, 20, 30, 40, 50, 60 minutes, the concentrations of menthone in YQP decoction were 0.058, 0.268, 0.216, 0.073, 0.065, 0.048, 0.048, 0.041, 0.038, 0.034 mg•L ⁻¹; the concentrations of menthol were 0.965, 2.847, 3.633, 2.420, 1.539, 1.189, 1.273, 1.188, 0.905, 0.663 mg•L ⁻¹; the concentrations of pulegone were 0.355, 0.522, 0.598, 0.477, 0.374, 0.374, 0.339, 0.355, 0.248, 0.251 mg•L ⁻¹; and the total concentrations were 1.377, 3.637, 4.446, 2.970, 1.979, 1.611, 1.660, 1.583, 1.191, 0.947 mg•L ⁻¹, respectively. The results showed that the contents of menthone, menthol and pulegone in YQP decoctions were heavily influenced by the decocting time. The fragrance was volatilized fiercely at about 5 minutes after boiling, with larger concentrations of the above three volatile components in decoction; the fragrance got weak after 15 minutes of boiling, the concentrations of menthone, menthol and pulegone in YQP decoctions were significantly decreased, indicating that the traditional decocting method "taking when the fragrance is volatilized fiercely" has some scientific foundation.

6.
Rev. colomb. cienc. pecu ; 28(3): 238-246, jul.-sep. 2015. ilus, tab
Article in English | LILACS | ID: lil-757271

ABSTRACT

Background: litter provides comfort to animals while improving productive performance and carcass quality. Objective: this study evaluated broiler performance, incidence of contact dermatitis, and quality of poultry litter of wood shavings and/or sugarcane bagasse (SB) after five consecutive flocks. Methods: two thousand birds were raised in five consecutive flocks composed of 400 chicks each. The experiment was set in a completely randomized design with five treatments and four repetitions. The treatments consisted of substituting wood shavings with different levels of SB (0, 25, 50, 75, and 100%). Results: litter density, pH, dry matter content, total nitrogen, and phosphorus did not vary between treatments. However, substituting wood shavings with SB increased moisture retention capacity of the litter and ammonia production. Neither carcass lesions nor productive performance, with the exception of weight gain and feed conversion ratio in the fifth flock, differed between treatments. Conclusions: substituting 75% of wood shavings with SB maintained litter quality and improved poultry performance.


Antecedentes: la cama propicia el confort y mejora el desempeño productivo y la calidad de la canal de los pollos de engorde. Objetivo: el objetivo del presente estudio fue evaluar el desempeño productivo de pollos de engorde, la incidencia de dermatitis de contacto en la canal y la calidad de la cama de pollo compuesta de viruta de madera y/o bagazo de caña de azúcar (SB), usada en cinco lotes consecutivos. Métodos: dos mil aves fueron criadas en cinco lotes consecutivos, cada uno constituido por 400 pollitos, en un diseño completamente aleatorizado con cinco tratamientos y cuatro repeticiones. Los tratamientos consistieron en diferentes niveles de sustitución de viruta de madera con SB (0, 25, 50, 75 y 100%). Resultados: la densidad, pH y contenidos de materia seca, nitrógeno total y fósforo no variaron entre los tratamientos. Sin embargo, sustituir viruta de madera con SB aumentó la capacidad de retención de humedad y la cantidad de amoníaco volatilizado en el galpón. Ni las lesiones en la canal y ni el desempeño productivo, con excepción de la ganancia de peso y conversión alimentaria en el quinto lote, difirieron entre los tratamientos. Conclusiones: sustituir 75% de la viruta de madera con SB mantuvo la calidad de la cama y mejoró el desempeño productivo de las aves.


Antecedentes: cama de frango propicia conforto e melhora o desempenho produtivo e a qualidade da carcaça das aves. Objetivo: este estudo avaliou o desempenho produtivo de frangos de corte, a incidência de dermatite de contato na carcaça e a qualidade da cama de frango composta de maravalha e/ou bagaço de cana (SB), usada em cinco lotes consecutivos. Métodos: duas mil aves foram criadas em cinco lotes consecutivos, compostos de 400 pintinhos cada, em delineamento inteiramente casualizado com cinco tratamentos e quatro repetições. Os tratamentos consistiram de diferentes níveis de substituição de maravalha com BC (0, 25, 50, 75 e 100%). Resultados: densidade, pH e teores de matéria seca, nitrogênio total e fósforo não variaram entre os tratamentos. Entretanto, substituir maravalha com SB aumentou a capacidade de retenção de umidade e a quantidade de amônia volatilizada no galpão. Nem as lesões na carcaça e nem o desempenho produtivo, com exceção do ganho de peso e conversão alimentar no quinto lote, diferiram entre os tratamentos. Conclusões: substituir 75% da maravalha com SB manteve a qualidade da cama e melhorou o desempenho produtivo das aves.

7.
Chinese Journal of Analytical Chemistry ; (12): 1349-1352, 2015.
Article in Chinese | WPRIM | ID: wpr-481850

ABSTRACT

A new method for determination of trace Cu, Cr, Mn, Co, Ni, Cd, Fe and Pb impurities in high pure tin oxide material was proposed. 0. 1 g of sample was successfully digested at 230℃ in 3 h when autoclaves with high pressure and high temperature were used. After that, over 99. 9% of the matrix Sn was removed by chloride volatilization at 150℃ for 1. 5 h, which eliminated the matrix effect and spectra interference in the following ICP-MS detection. The recoveries for all the analytes of the spiked test were 100%±5%, the RSDs for 6 runs of sample analysis were from 0. 09% to 3. 68%, and the limits of detection (LOD, 3σ) were from 0. 002 mg/kg to 0. 034 mg/kg, which indicated that the established method were of both accuracy and high sensitivity, and could be applied for the analysis of samples with purity up to 6N. Finally, three samples specified with 4N purity were analyzed by this method.

8.
Braz. dent. j ; 25(6): 543-545, Nov-Dec/2014. tab, graf
Article in English | LILACS | ID: lil-732248

ABSTRACT

This study aimed to evaluate the effect of maintaining a bottle of adhesive without its lid on the solvent loss of the etch-and-rinse adhesive systems. Three 2-step etch-and-rinse adhesives with different solvents (acetone, ethanol or butanol) were used in this study. Drops of each adhesive were placed on an analytical balance and the adhesive mass was recorded until equilibrium was achieved (no significant mass alteration within time). The solvent content of each adhesive and evaporation rate of solvents were measured (n=3). Two bottles of each adhesive were weighted. The bottles were maintained without their lids for 8 h in a stove at 37 ºC, after which the mass loss was measured. Based on mass alteration of drops, acetone-based adhesive showed the highest solvent content (46.5%, CI 95%: 35.8-54.7) and evaporation rate (1.11 %/s, CI95%: 0.63-1.60), whereas ethanol-based adhesive had the lowest values (10.1%, CI95%: 4.3-16.0; 0.03 %/s CI95%: 0.01-0.05). However, none of the adhesives bottles exhibited significant mass loss after sitting for 8 h without their lids (% from initial content; acetone - 96.5, CI 95%: 91.8-101.5; ethanol - 99.4, CI 95%: 98.4-100.4; and butanol - 99.3, CI 95%: 98.1-100.5). In conclusion, maintaining the adhesive bottle without lid did not induce significant solvent loss, irrespective the concentration and evaporation rate of solvent.


Este estudo avaliou o efeito da manutenção do frasco do adesivo sem sua tampa na perda de solvente de sistemas adesivos convencionais. Três adesivos convencionais de 2 passos com diferentes solventes (acetona, etanol ou butanol) foram usados neste estudo. Gotas de cada adesivo foram colocadas em uma balança analítica e a massa dos adesivos foi registrada até a obtenção do equilíbrio (nenhuma alteração significativa com o tempo). O conteúdo de solvente de cada adesivo e a taxa de evaporação dos solventes foram mensurados (n=3). Dois frascos de cada adesivo foram pesados. Os frascos foram mantidos sem suas tampas por 8 h em uma estufa a 37 ºC, seguido pela mensuração da pera de massa. Baseado na alteração de massa das gotas, o adesivo a base de acetona demonstrou o maior conteúdo de solvente (46,5%, IC 95%: 35,8-54,7) e de taxa de evaporação (1,11 %/s, IC95%: 0,63-1,60), enquanto que o adesivo à base de etanol teve os menores valores (10,1%, IC95%: 4,3-16,0; 0,03 %/s IC95%: 0,01-0,05). Entretanto, nenhum dos frascos dos adesivos exibiu perda significante de massa após ficar por 8 h sem suas tampas (% do conteúdo inicial; acetona - 96,5, IC95%: 91,8-101,5; etanol - 99,4, IC95%: 98,4-100,4; e butanol - 99,3, IC95%: 98,1-100,5). Em conclusão, a manutenção do frasco do adesivo sem tampa não induziu perda significante de solvente independente da concentração e da taxa de evaporação do solvente.


Subject(s)
Adult , Female , Humans , Aminophylline/therapeutic use , Anaphylaxis/chemically induced , Asthma/chemically induced , Sulfites/immunology , Urticaria/chemically induced , Administration, Topical , Aminophylline/immunology , Asthma/complications , Drug Labeling , Drug Hypersensitivity/immunology , Emollients/administration & dosage , Epinephrine/therapeutic use , Ethylenediamines/immunology , Hand Dermatoses/drug therapy , Patch Tests , Sulfites/administration & dosage
9.
Rev. bras. oftalmol ; 73(2): 98-102, Mar-Apr/2014. graf
Article in Portuguese | LILACS | ID: lil-718431

ABSTRACT

Objetivo: Avaliar por questionário qual o nível de facilidade ou dificuldade para aplicação tópica de medicações oculares: vaporização em olho fechado ou instilação de gotas em olho aberto e constatar por meio da observação de pacientes pelos autores qual o método que foi utilizado com maior adequação técnica para aplicação de drogas tópicas oculares. Métodos: A pesquisa foi um ensaio clínico pareado e randomizado, realizada nos meses de agosto e setembro de 2012 no ambulatório de Oftalmologia da Policlínica Ronaldo Gazolla (Campus Arcos da Lapa, Faculdade de Medicina da Universidade Estácio de Sá, RJ) em 50 pacientes conveniados de planos de saúde ou do SUS. Foi utilizado um frasco de colírio e um de vaporizador com solução Optive®. Cada participante aplicou em um dos olhos a solução por vaporização ou instilação de gotas através de um processo randomizado. Foi perguntado aos pacientes questões pré-formuladas sobre a praticidade de ambos os métodos e observada à técnica de aplicação. Resultados: 32% acharam difícil ou muito difícil a vaporização em olho fechado e 34% a instilação de colírio (p=0,9562). A dificuldade mais comum para ambos os métodos foi "acertar o olho" e ocorreu em 53% dos pacientes que tiveram dificuldades para vaporização e por 65%dos que apresentaram dificuldade para aplicação de colírio. 38% dos pacientes necessitaram de mais de uma instilação para aplicação do colírio, enquanto 30% dos pacientes precisaram de mais de uma aplicação para que a droga vaporizada tivesse contato com o olho (p=0,5224). Em 74% dos pacientes houve toque da ponta do colírio com os cílios, já com ...


Objective: Evaluate how difficult it is to apply ocular topical medications based on patient observation and answers to a questionnaire. Eye drops in open eyes were compared to vaporization in closed eyes. Methods: The study was a randomized clinical trial paired and held in the months of august and september of 2012 in the ophthalmological department of Polyclinic Ronaldo Gazolla (Arcos da Lapa Campus, Faculty of Medicine, University Estáciode Sá, RJ) in 50 patients. The Optive® ophthalmic solution was applied topically via an eyedrop bottle or a vaporizer through a randomized process. Patients were asked pre-formulated questions about the practicality of both methods and the technique of topical ocular drug delivery was observed. Results: 32% informed that it was difficult or very difficult to vaporize and 34% to use eye drops (p=0,9562). The major problem described by patients was to direct the eye drop to the eye surface. This difficulty was considered by 53% for vaporization and by 65% for topical eye drop use. 38% of the patients needed more than one eye drop application to have eye drop contact, while 30% of the patients needed more than one application of vaporization in order to get drug eye contact (p=0,5224). In 74% of patients there were an eyedropper tip contact with cilia, however there was one eye finger contact when the medicine was vaporized (p=0,5433). Conclusion: The ease perceived by patients to instil eye drops in open eyes was equivalent compared to the vaporization in closed eyes; the method of spraying was performed more appropriately due to the high frequency of eyedrop tip touches on the ocular surface. .


Subject(s)
Humans , Male , Female , Middle Aged , Ophthalmic Solutions/administration & dosage , Administration, Ophthalmic , Instillation, Drug , Nebulizers and Vaporizers , Self Administration , Random Allocation , Surveys and Questionnaires , Drug Delivery Systems/methods , Aerosols
10.
Ciênc. rural ; 43(10): 1817-1823, Oct. 2013. ilus
Article in Portuguese | LILACS | ID: lil-686037

ABSTRACT

A volatilização representa um processo importante no deslocamento de agrotóxicos para o ambiente. As características físico-químicas da molécula do clomazone indicam que este possui potencial de volatilização. Em vista do exposto, para a realização deste estudo, foram conduzidos dois experimentos com o objetivo de avaliar a suscetibilidade das espécies: pepino, melão, milho, sorgo e arroz a diferentes formulações do herbicida clomazone na fase vapor. Para isso, foram utilizadas caixas de vidro hermeticamente fechadas, com a presença de diferentes formulações de clomazone e as espécies vegetais. As formulações utilizadas foram Gamit 360 CS®, Gamit 500 EC® e Gamit Star®. Com os resultados obtidos, foi possível concluir que, dentre as espécies avaliadas, independente da formulação utilizada, a de menor tolerância ao herbicida clomazone na fase vapor foi o sorgo, seguido do milho e do arroz.


Volatilization represents an important transport process of pesticides for the environment. The clomazone physico-chemical properties indicate that molecule has the potential of volatilization. Therefore, for this study two experiments were carried with the objective of evaluating the species susceptibility: cucumber, melon, corn, sorghum and rice to different formulations of the herbicide clomazone in the vapor-phase. Glass boxes were used with the presence of clomazone formulations and plant species. The formulations used were Gamit 360 CS®, Gamit 500 EC® and Gamit Star®. As a main result it was conclude that among the species that were tested, independent of the formulation used, the lowest tolerance to clomazone herbicide in the vapor phase was sorghum, followed by corn and rice.

11.
Environmental Health and Toxicology ; : e2012008-2012.
Article in English | WPRIM | ID: wpr-118823

ABSTRACT

OBJECTIVES: The goal was to model and quantify the atmospheric concentrations of volatile organic compounds (VOCs) as the result of the Hebei Spirit oil spill, and to predict whether the exposure levels were abnormally high or not. METHODS: We developed a model for calculating the airborne concentration of VOCs that are produced in an oil spill accident. The model was applied to a practical situation, namely the Hebei Spirit oil spill. The accuracy of the model was verified by comparing the results with previous observation data. The concentrations were compared with the currently used air quality standards. RESULTS: Evaporation was found to be 10- to 1,000-fold higher than the emissions produced from a surrounding industrial complex. The modeled concentrations for benzene failed to meet current labor environmental standards, and the concentration of benzene, toluene, ortho- meta- para-xylene were higher than the values specified by air quality standards and guideline values on the ocean. The concentrations of total VOCs were much higher than indoor environmental criteria for the entire Taean area for a few days. CONCLUSIONS: The extent of airborne exposure was clearly not the same as that for normal conditions.


Subject(s)
Humans , Benzene , Petroleum Pollution , Toluene , Volatile Organic Compounds , Volatilization , Xylenes
12.
Ciênc. rural ; 41(12): 2053-2059, Dec. 2011. ilus, tab
Article in Portuguese | LILACS | ID: lil-608072

ABSTRACT

A ureia é a principal fonte de N usada na agricultura, mas apresenta grandes perdas em arroz irrigado por alagamento. O objetivo deste trabalho foi avaliar a eficiência de fontes de N alternativas à ureia para utilização pelo arroz irrigado aplicadas em diferentes estádios de desenvolvimento da planta através da quantificação da volatilização de N-NH3 e de parâmetros agronômicos. O experimento foi realizado em campo nos anos agrícolas 2007/08 e 2008/09. O delineamento experimental foi de blocos ao acaso com quatro repetições. Os tratamentos foram compostos de diferentes fontes de N aplicados na semeadura, no perfilhamento e no estádio de diferenciação floral: testemunha sem aplicação de N, ureia, ureia+inibidor de urease, duas fontes de N líquido (N-28 e N- 30), sulfato de amônio e ureia + enxofre. Nas duas safras, a volatilização de N-NH3 na semeadura foi praticamente insignificante, enquanto no estádio V4 a fonte que menos volatilizou foi o sulfato de amônio. A resposta em produtividade variou entre os anos, provavelmente em função da disponibilidade de N no solo e aspectos climáticos. Quando vantajoso economicamente, o uso do inibidor de urease e o sulfato de amônio proporcionam produtividades semelhantes à fonte ureia.


Urea is the main source of N used in agriculture, but has large losses in irrigated rice. The objective of this study was to evaluate the efficiency of N sources alternative to urea for use by rice applied at different stages of plant development through the quantification of N-NH3 and agronomic parameters. The experiment was conducted in the field in the agricultural years 2007/08 and 2008/09. The experimental design was randomized blocks with four replications. The treatments consisted of different N sources applied at seeding, tillering and at the stage of floral differentiation: control without N, urea, urea + urease inhibitor, two sources of liquid N (N-28 and N-30) ammonium sulfate and urea + sulfur. In both seasons, the volatilization of N-NH3 at seeding was almost negligible, whereas in the V4 stage, the source that was less volatilized was the ammonium sulfate. Yield response varied among years, probably due to the availability of N in the soil and climatic aspects. When economically advantageous, the use of urease inhibitor and ammonium sulfate provide yields similar to urea supply.

13.
Ciênc. rural ; 40(6): 1283-1289, jun. 2010. ilus, tab
Article in Portuguese | LILACS | ID: lil-554628

ABSTRACT

A ureia é a principal fonte de nitrogênio (N) para o arroz irrigado, porém é bastante suscetível a perdas por volatilização de amônia. O uso do inibidor de urease N-(n-butil) triamida tiofosfórica (NBPT) pode minimizar esse problema, inibindo temporariamente a degradação enzimática da ureia. O objetivo deste trabalho foi avaliar, em duas condições de umidade do solo, o efeito do tratamento da ureia com o inibidor de urease NBPT sobre as perdas de N por volatilização de amônia e seu reflexo na produtividade de grãos e acumulação de nitrogênio pelo arroz irrigado (Oryza sativa). O experimento foi realizado em um Planossolo Háplico, em Capão do Leão, Rio Grande do Sul (RS). Avaliaram-se as combinações de duas condições de umidade do solo por ocasião da primeira aplicação de N em cobertura, no início do perfilhamento (solo úmido e saturado), duas fontes de nitrogênio (ureia não tratada e ureia tratada com NBPT) e três intervalos de tempo entre a primeira aplicação de N em cobertura e o início da irrigação (um, cinco e 10 dias). A dose utilizada de N foi de 120kg ha-1, parcelados 90kg ha-1 no início do perfilhamento, de acordo com os tratamentos, e 30kg ha-1, na diferenciação da panícula. Os tratamentos foram dispostos em delineamento de blocos ao acaso, com quatro repetições. As perdas de N por volatilização de amônia decorrentes do uso de ureia variaram de 15 (solo saturado) a 22 por cento (solo úmido) do nitrogênio aplicado, quando o intervalo entre a aplicação desse fertilizante e o início da irrigação foi de 10 dias. Estas foram reduzidas em 83 e 88 por cento em solo saturado e úmido, respectivamente, com a adição de ureia com NBPT. Apenas na aplicação de N realizada 10 dias antes do início da irrigação o uso de NBPT proporcionou maiores produtividade de grãos e acumulação de nitrogênio pelo arroz. O tratamento da ureia com NBPT possibilita que sua aplicação anteceda em até 10 dias o início da irrigação, sem prejuízos para a produtividade...


Urea is the main nitrogen source used in flooded rice fields, but it is prone to ammonia volatilization losses. The use of N-(n-butyl) thiophosphoric triamide (NBPT) urease inhibitor, as urea additive, can reduce this inconvenient, inhibiting temporarily urea enzymatic degradation. An experiment was carried out on a Planossolo Háplico (Albaqualf), from October 2004 to April 2005, in Capão do Leão, RS, Brazil, to evaluate the effect of NBPT inhibitor-treated urea on nitrogen losses by ammonia volatilization, rice grain yield, and rice nitrogen accumulation, in two soil moisture conditions. The treatments were arranged as a randomized complete block with two soil moisture conditions (moist and muddy), two nitrogen sources (non treated urea and urea treated with NBPT) and three time intervals between nitrogen application and flooding (1, 5, and 10 days) in a factorial design with four replications. Nitrogen rate was 120kg N ha-1, applied at 4- to 5- leaf stage (90kg N ha-1) and at panicle differentiation (30kg N ha-1). Volatilization losses as ammonia from the urea treatment varied from 15 percent (muddy soil) to 22 percent (moist soil) of the applied N, when the time interval between nitrogen application and flooding was 10 days. Addition of NBPT reduced 83 percent and 88 percent ammonia volatilization losses in muddy soil and moist soil conditions, respectively. For the 10 days interval between nitrogen application and flooding, NBPT treated urea promoted greater rice yield and nitrogen accumulation, compared to non treated urea. The use of NBPT inhibitor makes possible applying urea up to ten days before flooding with no decrease on rice grain yield and nitrogen accumulation.

14.
Rev. bras. oftalmol ; 68(6): 327-331, nov.-dez. 2009. tab
Article in Portuguese | LILACS | ID: lil-543763

ABSTRACT

OBJETIVO: Avaliar por questionário qual o nível de dificuldade para aplicação tópica de medicações oculares: vaporização ou gotas através da observação do paciente e qual método foi tecnicamente melhor utilizado para aplicação de drogas tópicas oculares. MÉTODOS: A pesquisa foi realizada no decorrer de 2008 e 2009 no ambulatório de oftalmologia da Policlínica Ronaldo Gazolla. Foi utilizado um frasco de colírio e um de vaporizador com solução de carboximetilcelulose sódica a 0,5 por cento. Cada participante aplicou em um dos olhos a solução por vaporização ou instilação de gotas através de um processo randomizado. Foi perguntado ao paciente questões pré-formuladas sobre a praticidade de ambos os métodos. RESULTADOS: Considerando o grau de dificuldade de administração tópica ocular: 36 por cento acharam difícil ou muito difícil a vaporização e 14 por cento a instilação de colírio. As dificuldades descritas pelos pacientes foram relatadas por 64 por cento dos pacientes para vaporização e por 34 por cento para aplicação de colírio (p= 0,0027). Já 42 por cento dos pacientes necessitaram de mais de uma instilação para aplicação do colírio, enquanto 36 por cento dos pacientes precisaram de mais de uma aplicação para que a droga vaporizada tivesse contato com o olho (p= 0,49). Em 56 por cento dos pacientes houve toque da ponta do colírio com os cílios, já com o vaporizador não houve toque (p=0,0001). CONCLUSÃO: A vaporização foi o método mais seguro para evitar a contaminação do frasco. A maior facilidade percebida pelos pacientes ao instilar o colírio em relação a vaporização foi devido a terem apoiado a ponta do frasco nos tecidos oculares.


OBJECTIVE:Evaluate how difficult it is to apply ocular topical medications based on patient observation and answers to a questionnaire. Eye drops were compared to vaporization. METHODS: The study was performed in 2008 and 2009 in Policlinica Ronaldo Gazolla ophthalmological ambulatory. An eyedropper and a vaporizer with carboximetilcelulose 0,5 percent were used. Each individual tested applied randomly on one of their eyes an eye drop or vaporization. The patients had to answer questions about the practice concerning both forms of topical eye drug application. RESULTS: 36 percent informed that it was difficult or very difficult to vaporize and 14 percent to use eye drops. Problems described by patients were considered by 64 percent for vaporization and by 34 percent for topical eye drop use (p= 0,0027). 42 percent of the patients needed more than one eye drop application to have eye drop contact , while 36 percent of the patients needed more than one application of vaporization in order to get drug eye contact (p= 0,49). In 56 percent of patients there were an eyedropper tip contact with cilia, however there was not contact when the medicine was vaporized (p=0,0001). CONCLUSION: Vaporization was the safest method to avoid topical ocular drug contamination by manipulation; the greater facility noticed for patients when they administered eye drops was achieved using eye tissues as an eyedropper support.


Subject(s)
Administration, Topical , Eye , Self Administration , Ophthalmic Solutions/administration & dosage , Volatilization
15.
Eng. sanit. ambient ; 14(4): 443-448, out.-dez. 2009. ilus, tab
Article in Portuguese | LILACS | ID: lil-537663

ABSTRACT

O principal objetivo deste trabalho foi a avaliação quantitativa da influência do etanol sobre a volatilização de BTEX (benzeno, tolueno, etilbenzeno e xilenos) em mistura de gasolina e etanol anidro 25 por cento (v/v) em colunas experimentais, que simularam solos contaminados com gasolina pura e gasolina/etanol. Todos os BTEX apresentaram expressivo aumento das taxas de volatilização na coluna contendo a mistura gasolina/etanol. Porém, em termos percentuais, o maior e menor aumento nas taxas de volatilização foi observado para tolueno e benzeno, respectivamente. Em amostras de controle, com o percentual de etanol variando entre 0 e 25 por cento, não foi observado aumento no grau de volatilização do etilbenzeno, enquanto que o grau de volatilização dos xilenos foi reduzido. Estes resultados sugerem que, além de forças de interação intermoleculares, efeitos de interação líquido/estrutura do solo podem estar exercendo importante papel na volatilização dos BTEX.


The main objective of this paper was the quantitative evaluation of the ethanol's influence about the volatilization of BTEX (benzene, toluene, ethylbenzene and xylenes) in a mixture of gasoline and anhydrous ethanol 25 percent (v/v) in experimental columns that simulated soil contamination with gasoline/ethanol. All the BTEX presented expressive increase of volatilization rates in the gasoline-ethanol column. However, in terms of percentage, the highest and lowest volatilization grades were observed for toluene and benzene, respectively. In batch tests (control samples), with mixtures of gasoline ethanol with 0 and 25 percent (v/v) in ethanol, no increase of the volatilization grade was observed for ethylbenzene and the volatilization grade for xylenes was reduced. Matrix effects seem to be, besides the intermolecular interaction forces, important contributions for the volatilization grade of BTEX in this kind of sample.

16.
Ciênc. rural ; 38(8): 2321-2326, Nov. 2008. ilus, tab
Article in Portuguese | LILACS | ID: lil-512033

ABSTRACT

Foi avaliada a redução da volatilização de amônia em cama de frangos por meio da adição de aditivos químicos em três experimentos. No primeiro experimento foram estudadas diferentes doses de fosfato: testemunha; 5, 10, 15, 20 e 25 por cento, adicionado à cama No segundo, foi estudado o efeito da umidade, para os mesmos tratamentos realizados no primeiro experimento. No terceiro experimento, foram testados diferentes aditivos na cama de frango (testemunha, Sal de Glauber, Enxofre, Sulfato de cobre, Fosfato, Sulfato de alumínio e Carbonato de sódio, nos níveis de concentração de: 1,2,3,4 e 5 por cento). Como resultado, obteve-se que a dose de 15 por cento de superfosfatosimples foi a mais eficiente (P<0,05), inibindo em 95 por cento a volatilização. Pela variação no teor de umidade da cama, comprovou-se a influência inibitória da água na volatilização de amônia. Para os diferentes aditivos testados, foi constatado que o sulfato de cobre foi o melhor aditivo (P<0,05) a inibir a volatilização (62 por cento), seguido do sulfato de alumínio (53 por cento) e o superfosfato simples (43 por cento). O uso do carbonato de sódio aumentou os níveis de volatilização de amônia (+41 por cento) originados da cama de frangos.


The effect of additives to reduce volatilization of ammonia in poultry litter was evaluated in three experiments. In experiment one, different doses of phosphate, in the form of simple superphosphate, were studied by means of six treatments: 5, 10, 15, 20 and 25 percent added to the poultry litter. In the second experiment, the effect of humidity was verified by using the same treatments carried out in the previous experiment. In experiment three, different additives were tested in the poultry litter, following seven treatments: Glauber's salt; sulphur; copper sulphate, phosphate, aluminium sulphate; and sodium carbonate. In treatment one, the dose of 15 percent of simple superphosphate added to the poultry litter showed to be more effective than the other additives, for it has inhibited 95 percent of the volatilization. As to experiment two, a strong inhibiting influence of water in the volatilization of ammonia could be detected. As to experiment three, the copper sulphate was the best additive (P>0.05) to inhibit the poultry litter's volatilization of ammonia (62 percent), followed by both the aluminium sulphate (53 percent) and the simple superphosphate (43 percent). The use of carbonate has promoted an increase of 41 percent in the levels of ammonia volatilization.


Subject(s)
Animals , Ammonia/antagonists & inhibitors , Chemical Compounds , Chickens , Humidity/adverse effects
17.
Space Medicine & Medical Engineering ; (6)2006.
Article in Chinese | WPRIM | ID: wpr-580812

ABSTRACT

Objective To study effects of hydrated rate on compressed deformation properties of natural articular cartilage.Methods The mass losses of pure cartilage,subchondral bone and cartilage sample were measured under different volatilization time with constant vacuum temperature container of 40 ℃,and confined compressed deformation of different hydrated rates was measured using UMT-2 multi-specimen test system.Combined with cartilage structural equation originated by Mow,the aggregated modulus and permeability of cartilage tissue were obtained.Results The mass losses of pure cartilage,subchondral bone and cartilage sample functioned with a non-linear ascending relation with volatilization time in the environmental temperature of 40 ℃.The volatilization time for different hydrated rates of 75%,50%,25%and 0% was 17 min,35 min,54 min and 100 min,respectively.Higher hydrated rate produced more compressed deformation,lower aggregated modulus and higher permeability.Conclusion The viscoelastic mechanisms of flow-dependence and flow-independence are manifested by compressed deformations while the aggregated modulus and permeability could quantitatively depict the mutual relation between hydrated rate and compressed deformation.

18.
China Pharmacy ; (12)2001.
Article in Chinese | WPRIM | ID: wpr-523662

ABSTRACT

OBJECTIVE:To prepare solid dispersion for increasing solubility of quercetin METHODS:Using polyvinyl pyrrolidone(PVP) as the carrier,solid dispersion of quercetin was prepared by solvent -volatilization method The solubility of the solid dispersion was detected IR spectrometer and UV spectrometer were used to investigate the physical and chemical properties of the solid dispersion RESULTS:The solubility of solid dispersion was significantly increased compared with quercetin and the physical mixture Quercetin existed as ultrafine crystalline or molecular form in solid dispersion,so there was no chemical reaction between quercetin and PVP CONCLUSION:PVP could be used as the carrier of solid dispersion to increase the solubility of quercetin in water

19.
Ciênc. rural ; 27(2): 351-357, abr.-jun. 1997.
Article in English | LILACS | ID: lil-483556

ABSTRACT

Allelochemicals are compounds released by one plant or plant residues that may have a negative or positive effect on other plant. The importance of allelopathy was extensively explored during the past three decades, with the work concentrating in the extraction and identification of the chemicals, and demonstration of activity in petry dish experiments. These compounds interact in the soil environment similarly as herbicides and are subject to processes of degradation such as microbial degradation, oxidation, and photolysis, and processes of removal or transfer, such as volatilization and adsorption. The objective of this review was to access the fate of allelochemicals in the soil environment to help to find strategies to increase its activity. The activity of allelochemical is limited in time (because of slow release from the donor material) and in space (because of the interaction with the environment). Demonstration of allelopathy should include the fate of the proposed chemical in the soil environment, presenting studies of degradation and removal processes.


Aleloquímicos são compostos liberados por plantas ou seus resíduos e que podem ter efeito negativo ou positivo em outra planta. A importância da alelopatia foi estudada intensamente nas últimas três décadas, sendo que a maioria dos trabalhos abordou a extração e identificação dos compostos e, demonstração de seus efeitos em experimentos realizados em placas de petri. Estes químicos interagem no ambiente assim como os herbicidas e estão sujeitos aos processos de degradação por decomposição microbiana, fotólise e oxidação e, processos de remoção ou transferência como volatilização e adsorção. O objetivo desta revisão de literatura foi estudar o destino de aleloquímicos no ambiente para auxiliar na definição de estratégias para aumentar sua atividade. A atividade dos aleloquímicos é limitada pelo tempo (devido a liberação lenta do material doador) e pelo espaço (devido à interação com o ambiente). Demonstrações de alelopatia devem incluir o destino no ambiente do composto envolvido, apresentando estudos de processos de degradação e remoção.

20.
J Biosci ; 1989 Jun 14(2): 173-182
Article in English | IMSEAR | ID: sea-160725

ABSTRACT

Minimal inhibitory concentration values of HgCl2 and 5 organomercurials were determined against 24 mercury-resistant N2-fixing soil bacteria previously isolated from soil and identified in our laboratory. These bacterial strains also displayed multiple antibiotic resistant properties. Typical growth pattern of a highly mercury-resistant Beijerinckia sp (KDr2) was studied in liquid broth supplemented with toxic levels of mercury compounds. Four bacterial strains were selected for determining their ability to volatilize mercury and their Hg-volatilizing capacity was different. Cell-free extracts prepared from overnight mercury-induced cells catalyzed Hg2+-induced NADPH oxidation. Specific activities of Hg2+-reductase which is capable of catalyzing conversion of Hg2+ →Ηg (o) of 10 Hg-resistant bacterial strains are also reported.

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