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Sample records for butylated hydroxytoluene bht

  1. Understanding the chemistry behind the antioxidant activities of butylated hydroxytoluene (BHT): a review.

    Science.gov (United States)

    Yehye, Wageeh A; Rahman, Noorsaadah Abdul; Ariffin, Azhar; Abd Hamid, Sharifah Bee; Alhadi, Abeer A; Kadir, Farkaad A; Yaeghoobi, Marzieh

    2015-08-28

    Hindered phenols find a wide variety of applications across many different industry sectors. Butylated hydroxytoluene (BHT) is a most commonly used antioxidant recognized as safe for use in foods containing fats, pharmaceuticals, petroleum products, rubber and oil industries. In the past two decades, there has been growing interest in finding novel antioxidants to meet the requirements of these industries. To accelerate the antioxidant discovery process, researchers have designed and synthesized a series of BHT derivatives targeting to improve its antioxidant properties to be having a wide range of antioxidant activities markedly enhanced radical scavenging ability and other physical properties. Accordingly, some structure-activity relationships and rational design strategies for antioxidants based on BHT structure have been suggested and applied in practice. We have identified 14 very sensitive parameters, which may play a major role on the antioxidant performance of BHT. In this review, we attempt to summarize the current knowledge on this topic, which is of significance in selecting and designing novel antioxidants using a well-known antioxidant BHT as a building-block molecule. Our strategy involved investigation on understanding the chemistry behind the antioxidant activities of BHT, whether through hydrogen or electron transfer mechanism to enable promising anti-oxidant candidates to be synthesized.

  2. Visible-light promoted degradation of the commercial antioxidants butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT): a kinetic study.

    Science.gov (United States)

    Criado, Susana; Allevi, Carolina; Ceballos, Claudio; García, Norman A

    2007-01-01

    Visible-light photo-irradiation of the commercial phenolic antioxidants (PhAs) butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT), in the presence of vitamin B2 (riboflavin, Rf), in methanolic solutions and under aerobic conditions, results in the photo-oxidation of the PhAs. The synthetic dye photosensitiser Rose Bengal was also employed for auxiliary experiments. With concentrations of riboflavin and PhAs of ca. 0.02 mM and pigment is generated through an electron transfer process from BHT, with the subsequent production of superoxide anion radical (O2*-) by reaction with dissolved molecular oxygen. In parallel, the species singlet molecular oxygen, O2(1delta(g)), is also generated. Both reactive oxygen species produce the photodegradation of BHT. In the case of BHA, the lack of any effect exerted by superoxide dismutase drives out a significant participation of a O2(*-)-mediated mechanism. BHA mainly interacts with O2(1delta(g)) and exhibits a desirable property as an antioxidant--a relatively high capacity for O2(1delta(g)) de-activation and a low photodegradation efficiency by the oxidative species. Electrochemical determinations support the proposed photodegradative mechanism.

  3. Carcinogenicity study on butylated hydroxytoluene (BHT) in Wistar rats exposed in utero

    DEFF Research Database (Denmark)

    Olsen, P.; Meyer, Otto A.; Bille, N.;

    1986-01-01

    the controls, the extent of the reduction being dose related; the effect, which persisted throughout the study, was most pronounced in the males. The survival of BHT-treated F1 rats of both sexes was significantly better than that of the controls. No significant changes attributable to BHT treatment were found...... detected when the F1 rats were more than 2 yr old. Tumours were found in many other organs of some of the treated rats, but their incidence was not significantly different from that in controls. The role of BHT in the development of hepatocellular tumours requires further elucidation....

  4. Intake of butylated hydroxyanisole and butylated hydroxytoluene and stomach cancer risk : results from analyses in the Netherlands : cohort study

    NARCIS (Netherlands)

    Botterweck, A.A.M.; Verhagen, H.; Goldbohm, R.A.; Kleinjans, J.; Brandt, P.A. van den

    2000-01-01

    Both carcinogenic and anticarcinogenic properties have been reported for the synthetic antioxidants butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT). The association between dietary intake of BHA and BHT and stomach cancer risk was investigated in the Netherlands Cohort Study (NLCS)

  5. 21 CFR 182.3173 - Butylated hydroxytoluene.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Butylated hydroxytoluene. 182.3173 Section 182.3173 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Chemical Preservatives §...

  6. Effect of butylated hydroxytoluene, curcumin, propyl gallate and thiabendazole on cytochrome P450 forms in cultured human hepatocytes

    NARCIS (Netherlands)

    Price, R.J.; Scott, M.P.; Giddings, A.M.; Walters, D.G.; Stierum, R.H.; Meredith, C.; Lake, B.G.

    2008-01-01

    1. The objective of this study was to investigate the effects of four food chemicals, namely butylated hydroxytoluene (BHT), curcumin (CC), propyl gallate (PG) and thiabendazole (TB), on cytochrome P450 (CYP) forms in cultured human hepatocytes. 2. Treatment of human hepatocytes for 72 h with 2-200

  7. Antioxidant effect of mango seed extract and butylated hydroxytoluene in bologna-type mortadella during storage

    Directory of Open Access Journals (Sweden)

    Ana Lúcia Fernandes Pereira

    2011-03-01

    Full Text Available The effects of mango seed extract (MSE and butylated hydroxytoluene (BHT on pH, lipid oxidation, and color of Bologna-type mortadella during refrigerated storage for 21 days were studied. Bologna-type mortadella samples were formulated to contain 0.1% MSE, 0.2% MSE, or 0.01% BHT. After 14 days of storage, the products containing MSE 0.1 or 0.2% had higher pH values than those containing BHT 0.01%. Lipid oxidation values increased with storage time but were not affected by the type of antioxidant. The highest values for color parameter L* were observed for mortadella containing BHT 0.01% after 7, 14, and 21 days of storage. Values for the color parameters a* and b* tended to decrease during mortadella storage. Products containing 0.1 or 0.2% MSE showed higher values for color parameter a* and lower values for color parameter b* compared to those containing 0.01% BHT. It can be concluded that MSE can be used in 0.1 or 0.2% levels in Bologna-type mortadella with similar or better antioxidant effects than those of BHT 0.01%.

  8. Hydrolysis of the quinone methide of butylated hydroxytoluene in aqueous solutions.

    Science.gov (United States)

    Willcockson, Maren Gulsrud; Toteva, Maria M; Stella, Valentino J

    2013-10-01

    Butylated hydroxytoluene or BHT is an antioxidant commonly used in pharmaceutical formulations. BHT upon oxidation forms a quinone methide (QM). QM is a highly reactive electrophilic species that can undergo nucleophilic addition. Here, the kinetic reactivity of QM with water at various apparent pH values in a 50% (v/v) water-acetonitrile solution at constant ionic strength of I = 0.5 (NaCl)4 , was studied. The hydrolysis of QM in the presence of added acid, base, sodium chloride, and phosphate buffer resulted in the formation of only one product--the corresponding 3,5-di-tert-butyl-4-hydroxybenzyl alcohol (BA). The rate of BA formation was catalyzed by the addition of acid and base, but not chloride and phosphate species. Nucleophilic excipients, used in the pharmaceutical formulation, or nucleophilic groups on active pharmaceutical ingredient molecule may form adducts with QM, the immediate oxidative product of BHT degradation, thus having implications for drug product impurity profiles. Because of these considerations, BHT should be used with caution in formulations containing drugs or excipients capable of acting as nucleophiles.

  9. 21 CFR 172.115 - BHT.

    Science.gov (United States)

    2010-04-01

    ... Preservatives § 172.115 BHT. The food additive BHT (butylated hydroxytoluene), alone or in combination with... 21 Food and Drugs 3 2010-04-01 2009-04-01 true BHT. 172.115 Section 172.115 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR...

  10. Voltammetric Determination of Dinonyl Diphenylamine and Butylated Hydroxytoluene in Mineral and Synthetic Oil.

    Science.gov (United States)

    Xiang, Yaling; Qian, Xuzheng; Hua, Meng; Cheng, Bingxue; Chen, Wu; Li, Jian

    2016-07-02

    A method is reported for the determination of diphenylamine and butylated hydroxytoluene in mineral and synthetic oil. The procedure used differential pulse voltammetry with a glassy carbon electrode. This method was then used for determining these antioxidants in supporting electrolyte consisting of dilute sulfuric acid and sodium dodecyl sulfonate in ethanol. Anodic peaks were obtained for both analytes. Oxidation peaks at 250 mV were observed from a mixture of butylated hydroxytoluene and dinonyl diphenylamine, allowing their simultaneous determination. This approach was successfully used for the determination of dinonyl diphenylamine and butylated hydroxytoluene in fortified mineral and synthetic oils with good accuracy and precision.

  11. Rational Design and Synthesis of New, High Efficiency, Multipotent Schiff Base-1,2,4-triazole Antioxidants Bearing Butylated Hydroxytoluene Moieties

    Directory of Open Access Journals (Sweden)

    Wageeh A Yehye

    2016-06-01

    Full Text Available A new series of multipotent antioxidants (MPAOs, namely Schiff base-1,2,4-triazoles attached to the oxygen-derived free radical scavenging moiety butylated hydroxytoluene (BHT were designed and subsequently synthesized. The structure-activity relationship (SAR of the designed antioxidants was established alongside the prediction of activity spectra for substances (PASS. The antioxidant activities of the synthesized compounds 4–10 were tested by the DPPH bioassay. The synthesized compounds 4–10 inhibited stable DPPH free radicals at a level that is 10−4 M more than the well-known standard antioxidant BHT. Compounds 8–10 with para-substituents were less active than compounds 4 and 5 with trimethoxy substituents compared to those with a second BHT moiety (compounds 6 and 7. With an IC50 of 46.13 ± 0.31 µM, compound 6 exhibited the most promising in vitro inhibition at 89%. Therefore, novel MPAOs containing active triazole rings, thioethers, Schiff bases, and BHT moieties are suggested as potential antioxidants for inhibiting oxidative stress processes and scavenging free radicals, hence, this combination of functions is anticipated to play a vital role in repairing cellular damage, preventing various human diseases and in medical therapeutic applications.

  12. Rational Design and Synthesis of New, High Efficiency, Multipotent Schiff Base-1,2,4-triazole Antioxidants Bearing Butylated Hydroxytoluene Moieties.

    Science.gov (United States)

    Yehye, Wageeh A; Abdul Rahman, Noorsaadah; Saad, Omar; Ariffin, Azhar; Abd Hamid, Sharifah Bee; Alhadi, Abeer A; Kadir, Farkaad A; Yaeghoobi, Marzieh; Matlob, Abdulsalam A

    2016-06-28

    A new series of multipotent antioxidants (MPAOs), namely Schiff base-1,2,4-triazoles attached to the oxygen-derived free radical scavenging moiety butylated hydroxytoluene (BHT) were designed and subsequently synthesized. The structure-activity relationship (SAR) of the designed antioxidants was established alongside the prediction of activity spectra for substances (PASS). The antioxidant activities of the synthesized compounds 4-10 were tested by the DPPH bioassay. The synthesized compounds 4-10 inhibited stable DPPH free radicals at a level that is 10(-4) M more than the well-known standard antioxidant BHT. Compounds 8-10 with para-substituents were less active than compounds 4 and 5 with trimethoxy substituents compared to those with a second BHT moiety (compounds 6 and 7). With an IC50 of 46.13 ± 0.31 µM, compound 6 exhibited the most promising in vitro inhibition at 89%. Therefore, novel MPAOs containing active triazole rings, thioethers, Schiff bases, and BHT moieties are suggested as potential antioxidants for inhibiting oxidative stress processes and scavenging free radicals, hence, this combination of functions is anticipated to play a vital role in repairing cellular damage, preventing various human diseases and in medical therapeutic applications.

  13. Protective effect of butylated hydroxytoluene on sperm function in human spermatozoa cryopreserved by vitrification technique.

    Science.gov (United States)

    Merino, O; Aguagüiña, W E; Esponda, P; Risopatrón, J; Isachenko, E; Isachenko, V; Sánchez, R

    2015-03-01

    Butylhydroxytoluene (BHT), a synthetic analogue of vitamin E, shows antioxidant and antiviral properties and has been successfully used for mammalian sperm cryopreservation. In this study, BHT was included in a vitrification solution to determine its cryoprotective effect on human spermatozoa. Spermatozoa were selected by swim-up and vitrified in close sealed straw using either a combination of human tubal fluid (HTF), sucrose and BHT 1 mm (VMBHT), or only HTF and sucrose (VM). The optimal concentration of BHT was determined by the observation of preserved progressive sperm motility (PSM) after warming and detection of plasma membrane (PMI), membrane mitochondrial potential (ΔΨm) and DNA integrity. The presence of reactive oxygen species (ROS) was also detected. The PSM was significantly higher in the VMBHT group (80.86 ± 5.41%) compared with the VM group (68.9 ± 3.67%) (P < 0.05). Butylhydroxytoluene significantly preserved DNA integrity (4.0 ± 0.1% versus 6.1 ± 1.6%; P < 0.05) and reduced ROS production (5.5 ± 2.2 versus 8.6 ± 1.8%; P < 0.05). Plasma membrane and ΔΨm showed no statistical differences. One millimolar BHT effectively maintained cell function and due to its antioxidant and antiviral properties could be used in semen cryopreservation of patients with viral infections transmitted by seminal plasma.

  14. Final report on the safety assessment of BHT(1).

    Science.gov (United States)

    Lanigan, Rebecca S; Yamarik, Torill A

    2002-01-01

    BHT is the recognized name in the cosmetics industry for butylated hydroxytoluene. BHT is used in a wide range of cosmetic formulations as an antioxidant at concentrations from 0.0002% to 0.5%. BHT does penetrate the skin, but the relatively low amount absorbed remains primarily in the skin. Oral studies demonstrate that BHT is metabolized. The major metabolites appear as the carboxylic acid of BHT and its glucuronide in urine. At acute doses of 0.5 to 1.0 g/kg, some renal and hepatic damage was seen in male rats. Short-term repeated exposure to comparable doses produced hepatic toxic effects in male and female rats. Subchronic feeding and intraperitoneal studies in rats with BHT at lower doses produced increased liver weight, and decreased activity of several hepatic enzymes. In addition to liver and kidney effects, BHT applied to the skin was associated with toxic effects in lung tissue. BHT was not a reproductive or developmental toxin in animals. BHT has been found to enhance and to inhibit the humoral immune response in animals. BHT itself was not generally considered genotoxic, although it did modify the genotoxicity of other agents. BHT has been associated with hepatocellular and pulmonary adenomas in animals, but was not considered carcinogenic and actually was associated with a decreased incidence of neoplasms. BHT has been shown to have tumor promotion effects, to be anticarcinogenic, and to have no effect on other carcinogenic agents, depending on the target organ, exposure parameters, the carcinogen, and the animal tested. Various mechanism studies suggested that BHT toxicity is related to an electrophillic metabolite. In a predictive clinical test, 100% BHT was a mild irritant and a moderate sensitizer. In provocative skin tests, BHT (in the 1% to 2% concentration range) produced positive reactions in a small number of patients. Clinical testing did not find any depigmentation associated with dermal exposure to BHT, although a few case reports of

  15. Free radical-derived quinone methide mediates skin tumor promotion by butylated hydroxytoluene hydroperoxide: expanded role for electrophiles in multistage carcinogenesis.

    Science.gov (United States)

    Guyton, K Z; Bhan, P; Kuppusamy, P; Zweier, J L; Trush, M A; Kensler, T W

    1991-01-01

    Free radical derivatives of peroxides, hydroperoxides, and anthrones are thought to mediate tumor promotion by these compounds. Further, the promoting activity of phorbol esters is attributed, in part, to their ability to stimulate the cellular generation of oxygen radicals. A hydroperoxide metabolite of butylated hydroxytoluene, 2,6-di-tert-butyl-4-hydroperoxyl-4-methyl-2,5-cyclohexadienone (BHTOOH), has previously been shown to be a tumor promoter in mouse skin. BHTOOH is extensively metabolized by murine keratinocytes to several radical species. The primary radical generated from BHTOOH is a phenoxyl radical that can disproportionate to form butylated hydroxytoluene quinone methide, a reactive electrophile. Since electrophilic species have not been previously postulated to mediate tumor promotion, the present study was undertaken to examine the role of this electrophile in the promoting activity of BHTOOH. The biological activities of two chemical analogs of BHTOOH, 4-trideuteromethyl-BHTOOH and 4-tert-butyl-BHTOOH, were compared with that of the parent compound. 4-Trideuteromethyl-BHTOOH and 4-tert-butyl-BHTOOH have a reduced ability or inability, respectively, to form a quinone methide; however, like the parent compound, they both generate a phenoxyl radical when incubated with keratinocyte cytosol. The potency of BHTOOH, 4-trideuteromethyl-BHTOOH, and 4-tert-butyl-BHTOOH as inducers of ornithine decarboxylase, a marker of tumor promotion, was commensurate with their capacity for generating butylated hydroxytoluene quinone methide. These initial results were confirmed in a two-stage tumor promotion protocol in female SENCAR mice. Together, these data indicate that a quinone methide is mediating tumor promotion by BHTOOH, providing direct evidence that an electrophilic intermediate can elicit this stage of carcinogenesis. PMID:1846971

  16. Effect of previous chilling storage on quality loss in frozen (–20 °C sierra (Scomberomorus sierra muscle packed with a low-density polyethylene film containing butylated hydroxytoluene

    Directory of Open Access Journals (Sweden)

    Herlinda Soto-Valdez

    2015-03-01

    Full Text Available Rancidity development during frozen storage (–20 °C of sierra fish (Scomberomorus sierra was studied. Fillets were packed in low-density polyethylene films with and without butylated hydroxytoluene added (BHT-LDPE and LDPE respectively. Fillets stored with no package were used as control. Special attention was given to the effect of previous ice storage (0, 3, 6, 9 and 15 days on the quality of the frozen fish. Physical (pH and texture and chemical (peroxide value, PV and thiobarbituric acid index, TBA-i analyses were carried out. Lipid oxidation increased with ice storage time in fish muscle without film packing, being greater than the film packed muscle (with and without antioxidant. An effect of previous ice storage time was observed on the frozen product (in all treatments. However, fish muscle with film packing containing antioxidant showed less lipid deterioration. Under the conditions applied in this study, the plastic films with antioxidant prevented the lipids oxidation during the cold handling of the sierra muscle.

  17. Pathology of BHA- and BHT-induced lesions.

    Science.gov (United States)

    Moch, R W

    1986-01-01

    The pathology lesions from three studies, two with butylated hydroxyanisole (BHA) and one with butylated hydroxytoluene (BHT), are reviewed. When BHA was fed at 0.5 and 2.0% of the diet to F344 rats for two years, there was an increase in epithelial hyperplasia of the forestomach at both treatment levels. Papilloma and squamous-cell carcinoma of the forestomach were increased at the 2.0% level. When BHA was fed to beagle dogs at 1.0 and 1.3% of the diet for 180 days, no lesions/tumours of the distal oesophagus or stomach could be identified either at gross necropsy or by light or electron microscopy. The BHT was fed to Wistar rats at 0, 25, 100 and 250 mg/kg body weight. At the highest dose there was an increase in the number of rats with hepatocellular adenoma and with hepatocellular carcinoma.

  18. Collaborative study of a qualitative TLC-method for detection of antioxidants (BHA, BHT, gallates and NDGA) in food

    DEFF Research Database (Denmark)

    Guldborg, Merethe

    1981-01-01

    -proposed method, and an official French method. After extraction, the compounds are detected by TLC. Being a qualitative method the probability of obtaining correct results is a measure of the goodness of the method, and the study examines the influence on the probability of the following 3 factors: type......A method for the qualitative detection of antioxidants butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), the gallates and nordihydroguajaretic acid (NDGA) in bakery products and fat has been tested in a collaborative study. The method is similar to a IUPAC-method, an EEC...... of antioxidant, type of food, and concentration of antioxidant. From the study is was concluded that the method worked quite well for BHA, with a detection limit about 15 mg/kg, whereas it worked badly for BHT, the detection limit being higher than 30 mg/kg. For the gallates and NDGA the detection limit was 30...

  19. Effects of Aging Corn Diet Supplemented with Tea Polyphenol, Vitamin E and Butylated Hydroxytoluene on Growth Performance and Antioxidant Function of Meat Ducks%陈玉米饲粮中添加茶多酚、维生素 E和二丁基羟基甲苯对肉鸭生长性能和抗氧化功能的影响

    Institute of Scientific and Technical Information of China (English)

    张亚茹; 王忠; 蔡少敏; 张璐爽; 刘洋; 袁建敏; 夏兆飞

    2015-01-01

    The present study was conducted to investigate the effects of aging corn diet supplemented with tea polyphenol ( TP) , vitamin E and butylated hydroxytoluene ( BHT ) on growth performance and antioxidant function of meat ducks. A total of 192 one⁃day⁃old male ducks were randomly divided into 4 groups with 6 rep⁃licates per group and 8 ducks per replicate. Corn stored for 3 years was utilized to formulate appropriate basal diets. Ducks in the group Ⅰ ( control group) were fed the basal diet without antioxidant, and the others in groups Ⅱ, Ⅲ and Ⅳ were fed the basal diet supplemented with 120 mg/kg TP, vitamin E and BHT, respec⁃tively. This experiment lasted for 42 days. The results showed as follows:1) compared with the control group, TP significantly increased average daily gain ( ADG) at 22 to 42 days of age ( P0.05) . 2) Compared with the control group, TP significantly increased total antioxi⁃dant capacity ( T⁃AOC) at 21 and 42 days of age and catalase ( CAT) activity at 42 days of age in serum ( P<0.05), vitamin E significantly increased CAT activity at 42 days of age in serum (P<0.05), BHT significant⁃ly increased T⁃AOC at 21 days of age and CAT activity at 21 and 42 days of age in serum ( P<0.05) . In con⁃clusion, aging corn diet supplemented with TP and vitamin E can improve growth performance and antioxidant function of meat ducks, aging corn diet supplemented with BHT only can improve antioxidant function of meat ducks. Aging corn diet supplemented with TP has the best effect.%本试验旨在研究陈玉米饲粮中添加茶多酚( TP)、维生素E和二丁基羟基甲苯( BHT)对肉鸭生长性能和抗氧化功能的影响。选取1日龄雄性北京鸭192只,随机分为4组,每组6个重复,每个重复8只。以储存3年玉米作为能量原料,Ⅰ组(对照组)饲喂基础饲粮(不添加饲料抗氧化剂),Ⅱ、Ⅲ、Ⅳ组分别饲喂在基础饲粮中添加120 mg/kg TP、维生素E

  20. Effectiveness of the antioxidants BHA and BHT in selected vegetable oils during intermittent heating

    Directory of Open Access Journals (Sweden)

    Protopapa, Evangelia

    2002-06-01

    Full Text Available The heating performance of olive oil was compared with that of corn oil, olive-residue oil and 50:50 mixture of olive oil and corn oil. The oils were heated intermittently for two hours per day at a temperature of 175 ± 5° C for five consecutive days. Under such conditions thermal and oxidative decomposition of the oils takes place. Free fatty acid content, peroxide values, E1%1 cm, at 232 and 270nm, polar compounds, colour and viscosity, of the oils all increased, whereas the iodine values, smoke points, polyunsaturated fatty acids content and tocopherol concentration decreased. The effectiveness of butylated hydroxyanisole (BHA and butylated hydroxytoluene (BHT at a rate of 200 ppm in retarding the deterioration of oils during static heating (175 ± 5° C, was studied and it was found that BHA gave a slight protection to the olive-residue oil and the BHT gave some protection to the corn oil, while both antioxidants were relatively ineffective in the other oils.Se ha comparado el comportamiento del aceite de oliva al calentamiento con respecto al del aceite de maíz, el aceite de orujo y una mezcla al 50 % de aceite de oliva y aceite de maíz. Los aceites fueron calentados intermitentemente durante dos horas al día a una temperatura de 175º C ± 5º C durante cinco días consecutivos. Bajo tales condiciones tuvo lugar la descomposición térmica y oxidativa de los mismos. En todos los aceites aumentaron el contenido en ácidos grasos libres, el índice de peróxido, E1%1 cm, a 232 y 270 nm, los compuestos polares, el color y la viscosidad, mientras que el índice de yodo, el punto de humo, el contenido en ácidos grasos poliinsaturados y el contenido en tocoferoles disminuyeron. Se estudió la eficacia del 3-terc-butil-4-hidroxianisol (BHA y del butilhidroxitolueno (BHT en una proporción de 200 ppm en el retraso de la deterioración de los aceites durante el calentamiento estático (175 ± 5º C, encontrándose que el BHA

  1. 抗氧化剂BHT微胶囊化产品超微结构的测定%Study on Superstructure of Microencapsulated Antioxidant BHT

    Institute of Scientific and Technical Information of China (English)

    陈梅香

    2012-01-01

    Scanning electron microscopy (SEM) was applied to study the superstructure of microencapsulated star butylated hydroxytoluene (BHT) manufactured by various preparation techniques. The results showed that preparation techniques had significant effects on the structure of microencapsulated products, and thus affected the qualities of products. The research about superstructure of BHT could provide information for analyses on the quality of microencapsulate products.%用扫描电子显微镜(SEM)研究抗氧化剂二丁基羟基甲苯(BHT)微胶囊化产品的超微结构.观察了喷雾干燥法不同壁材组成和工艺条件下制作的微胶囊化产品的表面结构和内部结构,同时考察了喷雾干燥进风温度对微胶囊化产品膜结构的影响.结果表明,不同壁材组成和工艺条件下制作的微胶囊化产品的超微结构有较大差异,合适的壁材组成和工艺条件有利于提高产品质量,同时喷雾干燥进风温度对微胶囊化产品的结构有很大影响,从而也影响到产品的质量.微胶囊化产品超微结构的研究为分析影响产品质量的因素提供了重要依据.

  2. Field tests for mold resistance with BHT and BTA added to bamboo preservatives%不同添加剂对防霉剂野外防霉性能的影响

    Institute of Scientific and Technical Information of China (English)

    周月英; 孙芳利; 鲍滨福

    2013-01-01

    为了提高户外用竹材防霉剂的抗水解、光降解和抗氧化降解能力,采用向防霉剂中添加抗氧剂、紫外线吸收剂等方法,以4年生新伐毛竹Phyllostachys edulis为试材,以防霉剂丙环唑和戊唑醇为试剂,通过24周野外防霉实验,研究抗氧剂和紫外线吸收剂的添加对防霉剂防霉性能的影响.结果表明:抗氧剂二叔丁基对甲酚(BHT)对戊唑醇的防霉效力具有较好的促进作用,以质量分数1.0%戊唑醇为例,其处理材上表面的综合防霉效力为19.14%,加入BHT后提高到34.84%,而同时加入BHT和BTA这2种添加剂可提高到42.75%;然而,BHT对丙环唑防霉效果的影响不明显,紫外线吸收剂苯骈三氮唑(BTA)对戊唑醇防霉效果有减弱作用,对丙环唑则起到明显的促进作用,以质量分数1.0%的丙环唑处理材上表面为例,纯药剂防霉效力为14.43%,加入BTA后提高到37.23%,同时添加BHT和BTA防霉效力增加到54.12%.;同时添加BHT和BTA对所选2种防霉剂均能起到明显的防霉促进作用.%To improve resistance of bamboo preservatives against hydrolysis,light degradation,and oxidation degradation in outdoor applications,an antioxidant,butylated hydroxytoluene (BHT),and an ultraviolet absorber,benzotriazole (BTA),were added to the preservatives propiconazole and tebuconazole and applied to four-year-old bamboo samples.Then,the influence on mold resistance was studied through 24 weeks of field tests.Results showed that for a 1.0% concentration of tebuconazole,adding BHT alone increased resistance against mold fungi on the up-face of bamboo from 19.14% to 34.84% ; however,BTA alone reduced mold resistance.Nevertheless,adding both BHT and BTA to tebuconazole increased mold resistance to 42.75%.For a 1.0% propiconazole concentration,mold resistance on the up-face of bamboo with BTA alone increased from 14.4% to 37.23%,but BHT alone had little effect; adding both BHT and BTA to

  3. An improved financial tool to replace BHT

    CERN Multimedia

    2002-01-01

    In November, the BHT tool used to control financial data will be replaced by an improved and more powerful system, called CET for CERN Expenditure Tracking. The team in charge of CET. From left to right, sitting, Martyn Rankin, David McGlashan, standing, Per Gunnar Jonsson, James Purvis and Mikael Angberg. After 10 years of BHT at CERN, in order to face the challenges of the LHC era, and following the recommendations of the External Review Committee, the BHT application will be replaced by an improved and more powerful expenditure tracking tool called CET for CERN Expenditure Tracking. For those who are not familiar with it, the BHT, Budget Holders Toolkit, is a utility that provides a way to view CERN financial data. It is available for users who have access to at least one budget code. The new CET represents a tool that not only allows powerful analysis of the past, but also assists in forecasting the future. CET will offer significantly more functionality than BHT, including extended contract analysis, ...

  4. Safe Producing and Quality Traceability for Food Additive BHT Based on J2 EE%基于J2EE的食品添加剂二丁基羟基甲苯安全生产质量溯源

    Institute of Scientific and Technical Information of China (English)

    单萍; 万长林; 裘锋; 王蕾; 戴欢

    2014-01-01

    This paper introduces the main application of Butylated Hydroxytoluene ( BHT) as a food additive;for making sure of the reliability and effectiveness of food safety traceability data source in our country , this paper analyses the safe producing and quality traceability requirement elements and defines the key producing points based on the purchase , producing and sales proces-ses of BHT manufactories .Therefore, the BHT safe producing and quality traceability system that confirms to related standards was designed and implemented based on a free and open-source J2EE framework.With the integration of Spring , Hibernate and RFID technologies , this system managed the material purchasing , producing , inventorying , and product selling information , could realize the monitoring and quality tracing of BHT producing and sales .%介绍二丁基羟基甲苯(BHT)作为添加剂在食品方面的主要应用;为确保我国食品安全溯源数据来源的可靠性和有效性,本文根据BHT生产企业的物料采购、产品生产和销售流程,分析BHT生产企业安全生产和质量溯源的需求,定义过程中的关键控制点。参考相关国家标准,以目前较为成熟的企业级应用开发标准J2EE为基础,研究和设计一个BHT安全生产质量溯源管理系统,应用Spring、Hibernate、RFID等技术,对原料采购、生产、仓储和销售过程进行信息化管理,实现了BHT生产、加工和销售环节的全链条追溯。

  5. Antioxidant BHT Modelling Migration from Food Packaging of High Density Polyethylene Plastics into the Food Simulant

    Directory of Open Access Journals (Sweden)

    Chi Haitao

    2015-09-01

    Full Text Available Made of High Density Polyethylene (HDPE films containing antioxidant 2, 6-di-tert-butyl-p-cresol (BHT, film samples were manufactured by plastic extrusion equipment, 95% ethanol aqueous solution simulating liquid was used for stimulant, using High Performance Liquid Chromatography (HPLC for the long-term migration test of 4 kinds of HDPE films containing different concentrations of antioxidant BHT. The migration data were processed by using Weibull model and then the migration model was specific under experimental conditions. Migration model was setup using the migrating data by Weibull model to fitting real experimental data. Using empirical formula reported FDA model formula and the diffusion coefficient constant D, calculated by the FDA model. Two kinds of model numerical after compared according to FDA model transfer numerical literature that is far lower than the actual test migration value. According to the actual test migration value, Weibull model numerical and experimental tests that the migration software fitting values are consistent.

  6. Dramatic solvent effect on the synergy between α-tocopherol and BHT antioxidants.

    Science.gov (United States)

    Marteau, Clémentine; Favier, Dominique; Nardello-Rataj, Véronique; Aubry, Jean-Marie

    2014-10-01

    During the DPPH scavenging assay carried out in non polar and non protic solvents, such as toluene, BHT regenerates α-tocopherol from tocopheryl radical, whereas in polar and protic solvents, like methanol, no regeneration is observed due to a fast electron transfer reaction from the tocopheryl radical to the reactive DPPH radical. Surprisingly, in the presence of a small amount of alcohol, the synergy is exalted and BHT regenerates twice as much α-tocopherol due to a nucleophilic addition of short alcohols on the BHT oxidation product, giving a new phenolic co-antioxidant.

  7. Ascorbate protects against tert-butyl hydroperoxide inhibition of erythrocyte membrane Ca2+ + Mg2(+)-ATPase.

    Science.gov (United States)

    Moore, R B; Bamberg, A D; Wilson, L C; Jenkins, L D; Mankad, V N

    1990-05-01

    The incubation of erythrocyte suspensions or isolated membranes containing a residual amount of hemoglobin (0.04% of original cellular hemoglobin) with tert-butyl hydroperoxide (tBHP, 0.5 mM) caused significant inhibition of basal and calmodulin-stimulated Ca2+ + Mg2(+)-ATPase activities and the formation of thiobarbituric acid reactive products measured as malondialdehyde. In contrast, the treatment of white ghosts (membranes not containing hemoglobin) with tBHP (0.5 mM) did not lead to appreciable enzyme inhibition within the first 20 min and did not result in malondialdehyde (MDA) formation. However, the addition of either 10 microM hemin or 100 microM ferrous chloride + 1 mM ADP to white ghosts produced hydroperoxide effects similar to those in pink ghosts (membranes with 0.04% hemoglobin). The concentrations of hemin and ferrous chloride which caused half-maximal inhibition of Ca2+ + Mg2(+)-ATPase activity at 10 min were 0.5 and 30 microM, respectively. The effects of several antioxidants (mannitol, thiourea, hydroxyurea, butylated hydroxytoluene, and ascorbate) were investigated for their protective effects against oxidative changes resulting from tBHP treatment. Over a 30-min incubation period only ascorbate significantly reduced the enzyme inhibition, MDA formation, and protein polymerization. Thiourea and hydroxyurea decreased MDA formation and protein polymerization but failed to protect against the enzyme inhibition. Butylated hydroxytoluene was similar to thiourea and hydroxyurea but with better protection at 10 min. Mannitol, under these conditions, was an ineffective antioxidant for all parameters tested.

  8. Effect of penicillin on fatty acid synthesis and excretion in Streptococcus mutans BHT

    Energy Technology Data Exchange (ETDEWEB)

    Brissette, J.L.; Pieringer, R.A.

    1985-03-01

    Treatment of exponentially growing cultures of Streptococcus mutans BHT with growth-inhibitory concentrations (0.2 microgram/ml) of benzylpenicillin stimulates the incorporation of (2-/sup 14/C) acetate into lipids excreted by the cells by as much as 69-fold, but does not change the amount of /sup 14/C incorporated into intracellular lipids. At this concentration of penicillin cellular lysis does not occur. The radioactive label is incorporated exclusively into the fatty acid moieties of the glycerolipids. During a 4-hr incubation in the presence of penicillin, the extracellular fatty acid ester concentration increases 1.5 fold, even though there is no growth or cellular lysis. An indication of the relative rate of fatty acid synthesis was most readily obtained by placing S. mutans BHT in a buffer containing /sup 14/C-acetate. Under these nongrowing conditions free fatty acids are the only lipids labeled, a factor which simplifies the assay. The addition of glycerol to the buffer causes all of the nonesterified fatty acids to be incorporated into glycerolipid. The cells excrete much of the lipid whether glycerol is present or not. Addition of penicillin to the nongrowth supporting buffer system does not stimulate the incorporation of (/sup 14/C)-acetate into fatty acids.

  9. Butyl methoxy dibenzoylmethane.

    Science.gov (United States)

    Kockler, Jutta; Robertson, Sherryl; Oelgemöller, Michael; Davies, Murray; Bowden, Bruce; Brittain, Harry G; Glass, Beverley D

    2013-01-01

    A comprehensive profile on Butyl methoxy dibenzoylmethane, one of the most commonly used ultraviolet (UV) filters in topical sunscreen products, is prepared. This UV filter, often referred to as Avobenzone, has its main absorbance in the UVA I region of the spectrum and is susceptible to photodegradation. The profile contains the following sections: general information, use and mechanism of action, method of preparation, physical characteristics, methods of analysis, stability, and toxicity. The physical characteristics section includes the melting range, differential scanning calorimetry, partition coefficient, ionization constant, solubility, and UV, infrared, nuclear magnetic resonance ((1)H NMR and (13)C NMR) and mass spectrometry and X-ray powder diffractometry. The method of analysis section in addition to compendial identification and purity and assay methods includes thin-layer gas and high-performance liquid chromatography. The photostability and photostabilization of Butyl methoxy dibenzoylmethane, in addition to its toxicity, are also documented.

  10. Canonical structure of BHT massive gravity in warped AdS3 sector

    Science.gov (United States)

    Mahdavian Yekta, Davood

    2016-08-01

    We investigate the asymptotic structure of the three dimensional Warped Anti-de Sitter (WAdS3) black holes in the Bergshoeff-Hohm-Townsend (BHT) massive gravity using the canonical Hamiltonian formalism. We define the canonical asymptotic gauge generators, which produce the conserved charges and the asymptotic symmetry group for the WAdS3 black holes. The attained symmetry group is described by a semi-direct sum of a Virasoro and a Kač-Moody algebra. Using the Sugawara construction, we obtain a direct sum of two Virasoro algebras. We show that not only the asymptotic conserved charges satisfy the first law of black hole thermodynamics, but also they lead to the expected Smarr formula for the WAdS3 black holes. We also show that the black hole's entropy obeys the Cardy formula of the dual conformal field theory (CFT).

  11. Canonical structure of BHT massive gravity in warped AdS{sub 3} sector

    Energy Technology Data Exchange (ETDEWEB)

    Mahdavian Yekta, Davood, E-mail: d.mahdavian@hsu.ac.ir

    2016-08-10

    We investigate the asymptotic structure of the three dimensional Warped Anti-de Sitter (WAdS{sub 3}) black holes in the Bergshoeff–Hohm–Townsend (BHT) massive gravity using the canonical Hamiltonian formalism. We define the canonical asymptotic gauge generators, which produce the conserved charges and the asymptotic symmetry group for the WAdS{sub 3} black holes. The attained symmetry group is described by a semi-direct sum of a Virasoro and a Kač–Moody algebra. Using the Sugawara construction, we obtain a direct sum of two Virasoro algebras. We show that not only the asymptotic conserved charges satisfy the first law of black hole thermodynamics, but also they lead to the expected Smarr formula for the WAdS{sub 3} black holes. We also show that the black hole's entropy obeys the Cardy formula of the dual conformal field theory (CFT).

  12. Role of alkaline-tolerant fungal cellulases in release of total antioxidants from agro-wastes under solid state fermentation

    Digital Repository Service at National Institute of Oceanography (India)

    Ravindran, C.; Varatharajan, G. R.; Karthikeyan, A.

    Division, National Institute of Oceanography, Council of Scientific and Industrial Research (CSIR), Dona Paula, Goa, India-403 004. * Corresponding author: cravindran@nio.org INTRODUCTION Phenolic compounds of plant materials have numerous health... properties of synthetic antioxidants, such as butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA), provide motivation to consider the use of plant materials as important possible sources of compounds with the potential to be developed...

  13. Dietary exposure of children and teenagers to benzoates, sulphites, butylhydroxyanisol (BHA) and butylhydroxytoluen (BHT) in Beirut (Lebanon).

    Science.gov (United States)

    Soubra, L; Sarkis, D; Hilan, C; Verger, Ph

    2007-02-01

    The acceptable daily intake (ADI) for a considered chemical is by definition the amount of that substance which can be ingested every day during the life time without appreciable health risk. The theoretical risk of exceeding the ADI for benzoates, sulphites, butylhydroxyanisol (BHA) and butylhydroxytoluen (BHT) has often been examined on the basis of worst case scenario. The aim of this paper is to assess the actual intake of the food additives listed above for a group of the Lebanese population (students aged between 9 and 18 years old) likely to be highly exposed to food additives through the consumption of processed foods. Dietary exposure was obtained by combining food consumption data with food additives levels determined by chemical analysis. Food products available in Lebanon and containing added benzoates, sulphites, BHA and BHT were identified. Overall 420 samples of foods and beverages were analysed. The determination of food additives residue levels was carried out according to the official methods adopted in "Lebanese Institute for agronomic research" (IRAL) on food as consumed. The acceptable daily intake (ADI) could be exceeded for sulphites and BHT by a fraction of the population, in particular within children of 9-13 years old. Among all food additive-containing foods, the highest contributors were: soft drinks to benzoates intake, nuts and canned juices to sulphites intake, bread and biscuits to BHA intake and chewing gum to BHT intake.

  14. Gaia16bhp, Gaia16bhq, Gaia16bht and Gaia16bhj transients confirmed by Mercator/Maia imaging

    Science.gov (United States)

    Blanco-Cuaresma, S.; Semaan, T.; Roelens, M.; Palaversa, L.; Mowlavi, N.; Eyer, L.

    2016-09-01

    We report confirmation of Gaia Science Alerts transients Gaia16bhp, Gaia16bhq, Gaia16bht and Gaia16bhj. Images were obtained in G and R bands of the Maia instrument mounted to the Flemish 1.2m Mercator telescope at Roque de los Muchachos observatory, La Palma, Canary Islands, Spain, on 2016 September 18-19.

  15. BHT的电化学性质研究%Study on Electrochemistry Nature of BHT

    Institute of Scientific and Technical Information of China (English)

    邓鹏; 巩东营; 李桂龙; 薛文通

    2013-01-01

    油脂在热、光、重金属和辐射等因素下,极易发生氧化而产生酸败,为此,需要在油脂中添加不同种类的抗氧化剂延缓氧化,达到延长货架期的目的.2,6-二丁基羟基甲苯(BHT)是油脂中常用的抗氧化剂.本文基于抗氧化剂BHT的介电性质,探讨了BHT的电化学行为.研究中以Nafion修饰玻碳电极作为工作电极、以LiClO4乙腈溶液作为电解质,采用循环伏安扫描测定法(CSV),从BHT的电化学性质方面对其抗氧化机理进行了阐述,且得到了在1.65×10-5-1.65×10-4mol/L范围内BHT加入量与氧化峰电流呈良好的线性关系,以探讨建立一种新型的油脂中抗氧化剂添加量快速测定方法.

  16. Efeito da Adição do Antioxidante BHT e do Armazenamento Sobre a Qualidade da Farinha de Carne e Ossos Para Frangos de Corte

    Directory of Open Access Journals (Sweden)

    Racanicci AMC

    2000-01-01

    Full Text Available Este estudo foi desenvolvido com a finalidade monitorar a qualidade da farinha de carne e ossos (FCO, durante o armazenamento prolongado (10 semanas, e avaliar os efeitos da adição do BHT (500mg/kg a esta farinha. Um lote fresco de FCO (41,12% PB e 9,14% EE foi dividido em seis partes iguais, sendo uma não tratada (CONTROLE e as demais tratadas com BHT em diferentes tempos de armazenamento (nos dias 0, 7, 14, 21 e 28: BHT/0, BHT/7, BHT/14, BHT/21 e BHT/28, respectivamente. As FCO foram armazenadas em ambiente diariamente monitorado e sua qualidade foi avaliada por amostragens semanais, com determinação do índice de peróxidos, cujo nível máximo obtido foi de aproximadamente 80meq/kg (CONTROLE. A partir da 4ª semana de armazenamento, foi conduzido um experimento com frangos de corte alimentados por 42 dias com rações à base de milho e farelo de soja, contendo cerca de 4% das FCO armazenadas. Foram utilizados 1.440 pintos de um dia, machos, distribuídos num delineamento em blocos casualizados, com 6 tratamentos e 6 repetições. Os resultados médios obtidos para peso vivo, ganho de peso, consumo de ração, conversão alimentar, mortalidade e refugagem e fator de produção foram submetidos à análise da variância e as médias dos tratamentos foram comparadas ao CONTROLE através do teste de Dunnett. As variáveis estudadas, em geral, não foram afetadas pelos tratamentos (p>0,05, indicando que, neste estudo, o uso da FCO oxidada ou das FCO protegidas pelo BHT, não influenciaram o desempenho das aves.

  17. Antioxidant effect of BHT and vitamin E on canola oil%抗氧化剂BHT和维生素E对菜籽油的抗氧化研究

    Institute of Scientific and Technical Information of China (English)

    汤务霞; 陈明涛; 阙晓莉

    2011-01-01

    油脂及富含油脂的食品易发生氧化酸败,为了防止其氧化最常见的方法是加入抗氧化剂.BHT和维生素E是两种常见的抗氧化剂.本文以酸价(AV)和过氧化值(POV)为指标,研究了单独使用BHT以及BHT和维生素E(VE)复配使用在(60±1)℃加速氧化下对菜籽油贮存稳定性的影响.研究结果表明:(1)在单独使用BHT作为抗氧化剂时,BHT对菜籽油有一定抗氧化性,其添加量为0.2‰时抗氧化效果最好,其抗氧化效果顺序为0.20‰>0.05‰>0.25‰ >0.15‰>0.01‰;(2)在BHT和VE复配使用时比单独使用BHT效果好,其最佳配比浓度为0.10‰BHT和0.10‰VE,其抗氧化作用效果的顺序为0.10‰ BHT+0.10‰ VE>0.15‰BHT +0.05‰VE>0.10‰BHT +0.05‰VE >0.05‰BHT+0.05‰VE>0.05‰BHT+0.10‰ VE>0.10‰ BHT +0.15‰VE>0.05‰BHT +0.15‰VE >0.15‰ BHT +0.15‰ VE >0.15‰ BHT+0.10‰ VE.%Lipids and oil - riched foods are easy oxidative and rancid. BHT and vitaminE (VE) are two common an-tioxidants in preventing food oxidation. According to the acid value (AV) and peroxide value (POV), antioxidantive effects of BHT alone and combination of BHT and VE on the storage stability of Canola oil under accelerated oxidative condition (60±l)t were studied. The results showed that; (1) when BHT used alone, the best concentration to prevent oxidation was 0. 20‰, and the order of BHA content on antioxidation was 0. 20‰ >0. 05‰ >0. 25‰ >0. I5‰ >0. 01‰; (2) when BHT and VE used at the same time, their antioxidantive effect was superior to BHT alone and the best combination was 0. 10 BHT and 0. 10 VE, and the order of antioxidantive effect was 0. 10‰ BHT +0. 10‰ VE >0. 15‰ BHT +0. 05‰ VE > 0. 10‰ BHT +0.05‰ VE >0. 05‰ BHT +0. 05‰ VE >0. 05‰ BHT +0. 10‰ VE >0. 10‰ BHT +0.15‰ VE >0. 05‰ BHT +0. \\5‰> VE >0. 15‰ BHT +0. 15‰ VE >0. 15‰ BHT +0.10‰ VE.

  18. Spatial analysis of temperature (BHT/DST) data and consequences for heat-flow determination in sedimentary basins

    Science.gov (United States)

    Forster, A.; Merriam, D.F.; Davis, J.C.

    1997-01-01

    Large numbers of bottom-hole temperatures (BHTs) and temperatures measured during drill-stem tests (DSTs) are available in areas explored for hydrocarbons, but their usefulness for estimating geothermal gradients and heat-flow density is limited. We investigated a large data set of BHT and DST measurements taken in boreholes in the American Midcontinent, a geologically uniform stable cratonic area, and propose an empirical correction for BHTs based on relationships between BHTs, DSTs, and thermal logs. This empirical correction is compared with similar approaches determined for other areas. The data were analyzed by multivariate statistics prior to the BHT correction to identify anomalous measurements and quantify external influences. Spatial patterns in temperature measurements for major stratigraphic units outline relations to regional structure. Comparision of temperature and structure trend-surface residuals reveals a relationship between temperature highs and local structure highs. The anticlines, developed by continuous but intermittent movement of basement fault blocks in the Late Paleozoic, are subtle features having closures of 10-30 m and contain relatively small hydrocarbon reservoirs. The temperature anomalies of the order of 5-7 ??C may reflect fluids moving upward along fractures and faults, rather than changes in thermal conductivity resulting from different pore fluids. ?? Springer-Verlag 1997.

  19. Vertical flow soil filter for the elimination of micro pollutants from storm and waste water

    DEFF Research Database (Denmark)

    Janzen, Niklas; Banzhaf, Stefan; Scheytt, Traugott

    2009-01-01

    ) to prevent clogging and was spiked with activated sludge to enhance microbial biomass and biodegradation potential. Compounds used as UV filters, antioxidants or plasticizers, namely 4-methylbenzylidene camphor (4-MBC), benzophenone-3 (BP-3), butylated hydroxytoluene (BHT), N-butylbenzenesulfonamide (NBBS...... rates of the most analytes decreased to 79–96%. The elimination performance of the hydrophilic compound NBBS declined to 21%. Balancing studies including the soil of the filter system revealed that degradation or transformation were both relevant elimination mechanism....

  20. Determination of BHA and BHT in Vegetable Oil by Gas Chromatography for Nitrogen- purge%氮吹-气相色谱法测定植物油BHA与BHT

    Institute of Scientific and Technical Information of China (English)

    敬永计; 夏燕平; 姚勇; 龙德尚; 彭小燕

    2011-01-01

    Objective To explore the pretreatment technique for the detection of BHA and BHT from edible oils and fats by using gas chromatography. Methods Comparing the test results of two extraction and purification methods of nitrogen - purge and vacuum concentration by gas chromatography in the same test conditions of GC. The chromatographic conditions were suggested as follows: Gas chrom Q( 80 ~ 100mesh) covered by10% QF - 1 ( m/m)in 2. 0 × 3 mm stainless steel column was used as stationary phase, injection temperature 200 ℃ , detector temperature 200 ℃ , column temperature 140 ℃ . Results The RSDs of two pretreatment technique were all lower than 5% , the recovery rate was 88. 7% - 96. 2% and the detection limit were 0. 004 g/Kg. Conclusion It showed no statistical difference between two pretreatment methods of nitrogen - purge and vacuum concentration. The gas chromatography of nitrogen - purge is simple and accurate, and has a good reproducibility for the determination of BHA and BHT from vegetable oil.%目的 探讨气相色谱法检测食用油脂中BHA、BHT样品的前处理法.方法 在相同检测条件下比较柱层析后氮吹和减压浓缩2种样品前处理方法的结果.色谱条件为:色谱柱为长20 m内径3 mm不锈钢柱,内装涂有10%QF-1(m/m)的Gas chrom Q(80~100目)担体.气化室温度200℃,检测室温度200 ℃,柱温140℃.结果 2种前处理方法的相对标准差均小于5%,回收率在88.7%~96.2%之间,RSD为2.70%~3.78%,检出限为0.004 g/kg.结论 2种前处理方法测定结果差异无统计学意义,氮吹-气相色谱法简便、准确、重现性好,可用于植物油中BHA、BHT的测定.

  1. Antioxidants used in oils, fats and fatty foods Antioxidantes utilizados em óleos, gorduras e alimentos gordurosos

    Directory of Open Access Journals (Sweden)

    Valéria Cristina Ramalho

    2006-07-01

    Full Text Available Lipid oxidation is certainly one of the most important alterations that affect both oils or fats and foods that contain them. It is responsible for the development of unpleasant taste and smell in foods, making them unsuitable for consuming. The use of antioxidants permits a longer useful life of these products. This work presents a bibliographic review of research carried out in order to evaluate the antioxidant activity of natural or synthetic substances used in the conservation of food lipid. Among such substances, the following antioxidants are highlighted: butylated hydroxyanisole (BHA, butylated hydroxytoluene (BHT, tertiary butylhydroquinone (TBHQ, propyl gallate (PG, tocopherols, phenolic acids and isolated compounds from rosemary and oregano.

  2. Antioxidant Efficacies of Rutin and Rutin Esters in Bulk Oil and Oil-in-Water Emulsion

    DEFF Research Database (Denmark)

    Lue, Bena-Marie; Sørensen, Ann-Dorit Moltke; Jacobsen, Charlotte;

    2017-01-01

    in a food product. This study aimed to evaluate the antioxidative efficiency of two derivatives of rutin, namely rutin laurate (C12:0) and rutin palmitate (C16:0) compared with their parent compound rutin and with butylated hydroxytoluene (BHT). Their efficiency as antioxidants at two different...... concentrations (25 and 200 µM) was assessed in bulk oil and in an o/w emulsion system without and with iron addition. All evaluated compounds revealed antioxidant effects. However, rutin and BHT were the most efficient antioxidants in bulk oil followed by rutin palmitate, whereas rutin laurate acted as either...... an antioxidant or a prooxidant at low and high concentrations (25 and 200 µM), respectively. In emulsions, rutin and BHT in high concentration (200 µM) were more efficient than rutin esters. Thus, alcylation of rutin with medium chain fatty acids did not improve the antioxidant ability, neither in bulk oil nor...

  3. Comparative study of the antioxidant activities of some lipase-catalyzed alkyl dihydrocaffeates synthesized in ionic liquid.

    Science.gov (United States)

    Gholivand, Somayeh; Lasekan, Ola; Tan, Chin Ping; Abas, Faridah; Wei, Leong Sze

    2017-06-01

    The solubility limitations of phenolic acids in many lipidic environments are now greatly improved by their enzymatic esterification in ionic liquids (ILs). Herein, four different ILs were tested for the esterification of dihydrocaffeic acid with hexanol and the best IL was selected for the synthesis of four other n-alkyl esters with different chain-lengths. The effect of alkyl chain length on the anti-oxidative properties of the resulted purified esters was investigated using β-carotene bleaching (BCB) and free radical scavenging method DPPH and compared with butylated hydroxytoluene (BHT) as reference compound. All four esters (methyl, hexyl, dodecyl and octadecyl dihydrocaffeates) exhibited relatively strong radical scavenging abilities. The scavenging activity of the test compounds was in the following order: methyl ester>hexyl ester⩾dodecyl ester>octadecyl ester>BHT while the order for the BCB anti-oxidative activity was; BHT>octadecyl ester>dodecyl ester>hexyl ester>methyl ester.

  4. Compound list: butylated hydroxyanisole [Open TG-GATEs

    Lifescience Database Archive (English)

    Full Text Available butylated hydroxyanisole BHA 00156 ftp://ftp.biosciencedbc.jp/archive/open-tggates/...LATEST/Human/in_vitro/butylated_hydroxyanisole.Human.in_vitro.Liver.zip ftp://ftp.biosciencedbc.jp/archive/o...pen-tggates/LATEST/Rat/in_vivo/Liver/Single/butylated_hydroxyanisole.Rat.in_vivo.Liver.Single.zip ftp://ftp....biosciencedbc.jp/archive/open-tggates/LATEST/Rat/in_vivo/Liver/Repeat/butylated_hydroxyanisole.Rat.in_vivo.Liver.Repeat.zip ...

  5. 21 CFR 182.3169 - Butylated hydroxyanisole.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Butylated hydroxyanisole. 182.3169 Section 182.3169 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Chemical Preservatives §...

  6. 76 FR 59906 - Fluazifop-P-butyl; Pesticide Tolerances

    Science.gov (United States)

    2011-09-28

    ... secondary residues of fluazifop-P-butyl in livestock commodities from consumption of fluazifop-P-butyl... Performance Liquid Chromatography/Ultra-Violet Spectrometry (HPLC/UV)) is available to enforce the tolerance... cover residues of the herbicide fluazifop-P-butyl, including its metabolites and degradates, but...

  7. Free radical scavenging potential, reducing power, phenolic and biochemical constituents of Porphyra species from India

    Digital Repository Service at National Institute of Oceanography (India)

    Pise, N.M.; Jena, K.B.; Maharana, D.; Gaikwad, D.; Jagtap, T.G.

    (0.1 mM in methanol), plant extract (0.1-0.4ml) adjusted to 3 ml by adding methanol, and initial absorbance and absorbance after 30min. were measured at 517nm. Butylated hydroxytoluene (BHT) was used as the standard. Reducing power Methanol... debris, and then dried at a constant temperature (60°C) in oven. The dried tissues were ground to a fine powder, and then extracted with methanol for 24 hrs at -20°C. The extracts were concentrated in a vacuum evaporator (BUCHI Rota vapor R-200...

  8. Biodiesel metílico de Dipteryx lacunifera: preparação, caracterização e efeito de antioxidantes na estabilidade à oxidação Methyl biodiesel from Dipteryx lacunifera: preparation, characterization and effect of antioxidant on the oxidation stability

    Directory of Open Access Journals (Sweden)

    Francisca Diana da Silva Araújo

    2010-01-01

    Full Text Available The objective of this work was to study the potentialities of Dipteryx lacunifera Ducke seeds oil for biodiesel production. The yield in oil was of 46.11 ± 0.37%. Methyl biodiesel was prepared by base catalyzed transesterification yielding 88.13% and percentage conversion of triglycerides to corresponding methyl ester of 89.1%. The addition of the tertiary butylhydroquinone (TBHQ, 50 ppm, butylated hydroxytoluene (BHT, 50 ppm and cashew nut shell liquid (CNSL, 2000 ppm antioxidants in the biodiesel contributed to the increase of the induction period of 2.97 h for 8.08; 6.06 and 6.02 h, respectively.

  9. Methyl biodiesel from Dipteryx lacunifera: preparation, characterization and effect of antioxidant on the oxidation stability; Biodiesel metilico de Dipteryx lacunifera: preparacao, caracterizacao e efeito de antioxidantes na estabilidade a oxidacao

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Francisca Diana da Silva; Moura, Carla Veronica Rodarte de; Chaves, Mariana H., E-mail: mariana@ufpi.edu.b [Universidade Federal do Piaui (UFPI), Teresina, PI (Brazil). Dept. de Quimica

    2010-07-01

    The objective of this work was to study the potentialities of Dipteryx lacunifera Ducke seeds oil for biodiesel production. The yield in oil was of 46.11 {+-} 0.37%. Methyl biodiesel was prepared by base catalyzed transesterification yielding 88.13% and percentage conversion of triglycerides to corresponding methyl ester of 89.1%. The addition of the tertiary butylhydroquinone (TBHQ, 50 ppm), butylated hydroxytoluene (BHT, 50 ppm) and cashew nut shell liquid (CNSL, 2000 ppm) antioxidants in the biodiesel contributed to the increase of the induction period of 2.97 h for 8.08; 6.06 and 6.02 h, respectively. (author)

  10. 2-(tert-Butyl-4-phenyloxetane

    Directory of Open Access Journals (Sweden)

    Filippo Maria Perna

    2017-02-01

    Full Text Available The two geometric isomers of 2-(tert-butyl-4-phenyloxetane have, for the first time, been prepared starting from the commercially available 4,4-dimethyl-1-phenylpentane-1,3-dione. The latter was reduced with NaBH4 to give a mixture of diastereomeric syn and anti diols which were then stereospecifically cyclized into the corresponding oxetanes with an overall yield for the two steps of 69.6%. The newly synthesized stereoisomeric four-membered oxygenated heterocycles were separated by column chromatography on silica gel and fully spectroscopically characterized.

  11. Organic Semiconductors and Conductors with tert-Butyl Substituents

    Directory of Open Access Journals (Sweden)

    Toshiki Higashino

    2012-08-01

    Full Text Available Tetrathiafulvalene (TTF, pentacene, and quarterthiophene with tert-butyl substituents are synthesized, and the crystal structures and the transistor properties are investigated. The tetracyanoquinodimethane (TCNQ complex of tert-butyl TTF constructs highly one-dimensional segregated columns with tetragonal crystal symmetry.

  12. An efficient and highly selective ortho-tert-butylation of p-cresol with methyl tert-butyl ether catalyzed by sulfonated ionic liquids

    Directory of Open Access Journals (Sweden)

    Alamdari Reza Fareghi

    2014-01-01

    Full Text Available A novel series of sulfonic acid-functionalized ionic liquids (SFILs was found to act as efficient catalysts for ortho-tert-butylation of p-cresol with methyl tert-butyl ether (MTBE as the tert-butylating agent without an added solvent. The mono o-tert-butylated product was obtained in up to 80.4% isolated yield and 95.2% selectivity under such green conditions. No O-tert-butylated byproducts were formed.

  13. [Determination of antioxidant residues in polymer food package using gas chromatography].

    Science.gov (United States)

    Xiong, Zhongqiang; Wang, Libing; Li, Ningtao; Yu, Yanjun; Jia, Xiaochuan

    2011-03-01

    A new method for the determination of antioxidants, butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA) and tertiary butylhydroquinone (TBHQ) in plastic food package by gas chromatography-electron capture detection (ECD) was developed. The antioxidants were extracted by cyclohexane with ultrasonic extraction, separated by an HP-50 + chromatographic column (30 m x 0.53 mm x 1 microm) and quantified by external standard method with an ECD detector. The average recoveries of antioxidants were 88% -93%, 92% - 101% and 83% -97% for BHT, BHA and TBHQ, respectively, at the spiking levels of 3.00 - 10.0 mg/kg. The corresponding relative standard deviations (RSDs, n = 5) were 2.01% - 2.89%, 2.11% - 3.19% and 2.99% - 4.02%, respectively. The limits of detection (S/N = 3) were 0.5, 0.5 and 0.8 mg/kg for BHT, BHA and TBHQ, respectively. The proposed method has been applied to the analysis of 5 kinds of polymer food package. The results indicated that all the above antioxidants were found in the practical polymer food package samples. Plastic food package contained BHT and BHA with the concentrations varying from 6.3 to 7.8 mg/kg and rubber food package contained all the three antioxidants with the concentrations varying from 9.3 to 28.4 mg/kg. This method is accurate, sensitive, highly reproducible and suitable for the analysis of residual antioxidants in polymer food package.

  14. Determination of synthetic phenolic antioxidants in soft drinks by stir-bar sorptive extraction coupled to gas chromatography-mass spectrometry.

    Science.gov (United States)

    Cacho, Juan Ignacio; Campillo, Natalia; Viñas, Pilar; Hernández-Córdoba, Manuel

    2015-01-01

    The synthetic phenolic antioxidants butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and tert-butyl hydroquinone (TBHQ) were pre-concentrated by stir-bar sorptive extraction and thermally desorbed (SBSE-TD) before analysis by GC-MS. Several parameters affecting the derivatisation step and both SBSE extraction and thermal desorption were carefully optimised. When the analyses of BHA and TBHQ in their acetylated, silylated and underivatised forms were compared, the best results were obtained when the in-situ derivatisation procedure with acetic anhydride was employed. Quantification was carried out using carvacrol as the internal standard, providing quantification limits of between 0.11 and 0.15 ng ml(-1), depending on the compound. Recovery assays for samples spiked at two concentration levels, 1 and 5 ng ml(-1), provided recoveries in the 81-117% range. The proposed method was applied in the analysis canned soft drinks and the analytes were found in five of the 10 samples analysed.

  15. Chemical constituents, anticancer, antimicrobial and antioxidant activities of essential oil from Anaphalis lacteal grown in Qinghai-Tibet Plateau.

    Science.gov (United States)

    Liu, Shi-Jun; Liao, Zhi-Xin; Liu, Chao; Sun, Jin-Yue

    2015-01-01

    The chemical constituent of the essential oil from Anaphalis lacteal was determined; 31 compounds, representing 93.91% of the total oil, were identified by gas chromatography-mass spectrometry analysis. Three Gram-positive bacteria species, three Gram-negative bacteria species and four fungi were used to determine antimicrobial activity; the results revealed that the essential oil had a remarkable antimicrobial effect against bacteria and a susceptive effect against fungus. The oil also possessed more efficient free-radical scavenging activities than butylated hydroxytoluene (BHT) with 50% inhibitory concentration (IC50) value 31 μg/mL (40 μg/mL for BHT). MTT assay illustrated that the oil expressed certain effect in inhibiting the growth of HeLa and Hep-6 cancer cells.

  16. Evaluation of two natural extracts (Rosmarinus officinalis L. and Melissa officinalis L.) as antioxidants in cooked pork patties packed in MAP.

    Science.gov (United States)

    Lara, M S; Gutierrez, J I; Timón, M; Andrés, A I

    2011-07-01

    Two natural extracts, from rosemary (Rosmarinus officinalis L.; Nutrox) and lemon balm (Melissa officinalis L.; Meliox) showing a potential antioxidant activity, have been evaluated and compared with a synthetic antioxidant (Butylated hydroxytoluene; BHT) and a control batch. Pork meat patties were made by addition of the mentioned compounds, cooked and packed in modified atmosphere and stored under illumination for 6 days. A descriptive sensory analysis was also conducted. The patties with natural extracts showed higher a*-values (P<0.001) than control and BHT samples. Cooked pork hardness was the lowest for Meliox batch after 0 and 3 days of storage in comparison with the rest of the batches. Nutrox batch showed the lowest TBARS values and hexanal content (P<0.05) throughout the storage period. The batches with natural antioxidants produced the highest concentrations of free thiol groups after 0 and 3 days. Differences in sensory attributes among batches were not detected by the judge panel.

  17. Solubilization of meso-carbon microbeads by potassium- or dibutylzinc-promoted butylation and structural analysis of the butylated products; Mesocarbon microbeads no butyl ka ni yoru kayoka to erareta butyl kabutsu no kozo kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Murata, S.; Zhang, Y.; Kidena, K.; Nomura, M. [Osaka University, Osaka (Japan). Faculty of Engineering

    1996-10-28

    Tetrahydrofuran (THF) solubility and structure of the butylated products of meso-carbon microbeads (MCMB) were studied experimentally. In experiment, MCMB-A and MCMB-B obtained from two kinds of coal-tar pitch were used as specimens. MCMBs were butylated by BZ method using dibutylzinc-butyl iodide and KT method using K-butyl iodide-THF, and the butylated products were successfully obtained. The butylated products were investigated through THF solubility test, {sup 13}C-NMR measurement and gel permeation chromatography (GPC) measurement. As the experimental result, a BZ method produced the butylated products at a yield of nearly 170%, while a KT method produced them at a yield of nearly 130%. The THF solubility was estimated to be 89-97%. As the study result of molecular weight distributions by GPC measurement of solvent solubles, the molecular weight of raw material MCMB was estimated to be 590-770 in terms of polystyrene. 6 refs., 2 figs., 1 tab.

  18. Improvement of frozen semen quality of Garut Sheep through the addition of α-tocopherol into yolk egg-skim milk diluent

    Directory of Open Access Journals (Sweden)

    Herdis

    2002-03-01

    Full Text Available The sperm is very fragile to lipid peroxide reaction, that it can easily broken during the process of freezing. To eliminate this consequences an antioxidant agent added into the extender. A research was done to observe the effect of antioxidant agent α-tocoferrol and butylated hydroxytoluene (BHT presence in the extender on the quality of frozen semen. Once week, semen from six male Garut sheep ages about 2.5 years old was collected using artificial vagina and egg yolk skim-milk diluent used as the extender. The semen were treated in egg yolk skim-milk diluent without antioxidant as control, in egg yolk skim-milk diluent with α- tocoferrol 0,2 g/100 ml diluent and in egg yolk skim-milk diluent with butylated hydroxytoluene 0,2 g/100 ml diluent. The after thawing observation shown that in egg yolk skim-milk diluent with α- tocoferrol had life percentage (75.0 ± 3.5% vs 64.8 ± 7.8% and membrane intact percentage (65.8 ± 6.8 % vs 55.2 ± 8.3% significantly higher than control (P<0,05 but insignificantly different from with BHT addition. The presence of α-tocoferrol in the diluent, the motility percentage consideraly higher (P<0.05 than (45.8 ± 3.8% using BHT addition (40.0 ± 4.5% but not different from control (41.7 ± 4.1%; while acrosomal intake percentage after α-tocoferrol (54.8% ± 3.3% expressively higher (p,0.05 than BHT addition (49.7 ± 3.6% or control (49.8 ± 3.5%. In conclusion the presence of α-tocoferrol in the diluent could improve the quality of Garut sheep frozen semen.

  19. DIVERSIDAD DE ORQUÍDEAS EPÍFITAS EN UN BOSQUE HÚMEDO TROPICAL (BH-T DEL DEPARTAMENTO DEL CHOCÓ, COLOMBIA.

    Directory of Open Access Journals (Sweden)

    HEIDY MEJÍA ROSERO

    2010-01-01

    Full Text Available Se evaluó la diversidad de orquídeas epífitas en un bosque húmedo tropical (bh-T, perteneciente al corregimiento de Tutunendo (Quibdó. En él fueron establecidas tres zonas de acuerdo al grado de intervención del bosque: poco (300 m2, medio (400 m2 y altamente intervenido (300 m2; dentro de estos fueron registrados 66 forófitos con un DAP ≥ a 20 cm, en los cuales se muestrearon las orquídeas huéspedes, obteniendo un registro total de 1.348 individuos, distribuidos en 49 especies y 20 géneros. Los géneros más representativos en número de especies fueron Maxillaria (11 y Dichaea (5. Según el índice de Shannon-Weiner, se aprecia una alta diversidad de orquídeas epífitas en el área de estudio (H’=3,30. En cuanto a las zonas de acuerdo al grado de intervención, el bosque medio y el poco intervenido fueron los más altos en diversidad, sin embargo, el altamente intervenido, donde se da el tipo de cultivo de tumba y siembra y la extracción maderera es constante, presentó los más bajos resultados. Según la prueba de Kruskal-Wallis, estas zonas presentaron diferencias significativas (P<0,05 en cuanto a la riqueza y abundancia de especies registradas. Evidentemente, la alta diversidad de este grupo de plantas puede deberse a algunas condiciones climáticas (precipitación, humedad e in- tensidad lumínica, que facilitan su establecimiento en el área.

  20. Phenol Tert-Butylation Catalyzed by Zeolite H-Mordenite

    Institute of Scientific and Technical Information of China (English)

    HAN Sen; LI Zhenhua; ZHANG Kui

    2005-01-01

    Para-tert-butyl phenol (p-TBP) and 2,4-di-tert-butyl phenol (2,4-DTBP) are widely used for the preparation of antioxidants. Zeolite catalysts showed good performance for the synthesis of p-TBP and 2,4-DTBP. In this work, zeolite H-mordenite (HM) catalyst was prepared and the alkylation of phenol with tert-butyl alcohol over zeolite HM catalyst was investigated at different reaction conditions. It is found that increasing temperature enhances the selectivity to p-TBP and the optimum reaction temperature for phenol conversion is 438 K. Increasing flow rate decreases phenol conversion apparently while the selectivity to p-TBP has a little increase. The suitable tert-butyl alcohol/phenol molar ratio is 2. Lower alcohol/phenol molar ratios are beneficial to p-TBP while higher ones are helpful for producing 2,4-DTBP.

  1. Embryolethality of butyl benzyl phthalate in rats

    Energy Technology Data Exchange (ETDEWEB)

    Ema, N.; Itami, T.; Kawasaki, H. (National Inst. Hyg. Science, Osaka (Japan))

    1991-03-15

    The developmental toxicity of butyl benzyl phthalate (BBP) was studied in Wistar rats. Pregnant rats were given BBP at a dosage of 0, 0.25, 0.5, 1.0 or 2.0% in the diet from day 0 to day 20 of pregnancy. Morphological examinations of the fetuses revealed no evidence of teratogenesis. In the 2.0% group, all dams exhibited complete resorption of all the implanted embryos, and their food consumption, body weight gain and adjusted weight gain during pregnancy were markedly lowered. To determine whether the embryolethality was the result of reduced food consumption during pregnancy, a pair-feeding study was performed in which the pregnant rats received the same amount of diet consumed by the 2.0% BBP-treated pregnant rats. The pair-fed and 2.0 % BBP-treated pregnant rats showed significant and comparable reductions in the adjusted weight gain. The number of live fetuses was lowered in the pair-fed group. However, the complete resorption of all the implanted embryos was not found in any of the pair-fed pregnant rats. The data suggest that the embryolethality observed in the 2.0 % BBP-treated pregnant rats is attributable to the effects o dietary BBP.

  2. Cytotoxicity and genotoxicity of butyl cyclohexyl phthalate.

    Science.gov (United States)

    Köksal, Çinel; Nalbantsoy, Ayse; Karabay Yavaşoğlu, N Ülkü

    2016-03-01

    Butyl cyclohexyl phthalate (BCP) is frequently used in personal care products, medical and household applications. The aim of this study is therefore to evaluate possible cytotoxicity and genotoxicity of BCP using in vitro and in vivo assays. The in vitro cytotoxic effect of BCP was investigated on mouse fibroblastic cell line (L929 cells) by MTT assay. The result showed that BCP inhibits cell proliferation in a concentration-dependent manner (IC50 value = 0.29 µg/mL). For genotoxicity assessment, tested concentrations of BCP demonstrated mutagenic activity in the presence of S9 mix with the Salmonella strain TA100 in the Ames test. Results showed that BCP is a secondary mutagenic substance even in low concentrations. The data obtained from 28-days repeated toxicity tests on mice revealed that BCP caused abnormalities of chromosome number, in a dose-dependent manner. Additionally, DNA damage, particularly DNA strand breaks, was assessed by Comet assay. The test result shows that BCP seemed to have genotoxic potential at a high level of exposure.

  3. Microbial degradation of methyl tert-butyl ether and tert-butyl alcohol in the subsurface

    Science.gov (United States)

    Schmidt, Torsten C.; Schirmer, Mario; Weiß, Holger; Haderlein, Stefan B.

    2004-06-01

    The fate of fuel oxygenates such as methyl tert-butyl ether (MTBE) in the subsurface is governed by their degradability under various redox conditions. The key intermediate in degradation of MTBE and ethyl tert-butyl ether (ETBE) is tert-butyl alcohol (TBA) which was often found as accumulating intermediate or dead-end product in lab studies using microcosms or isolated cell suspensions. This review discusses in detail the thermodynamics of the degradation processes utilizing various terminal electron acceptors, and the aerobic degradation pathways of MTBE and TBA. It summarizes the present knowledge on MTBE and TBA degradation gained from either microcosm or pure culture studies and emphasizes the potential of compound-specific isotope analysis (CSIA) for identification and quantification of degradation processes of slowly biodegradable pollutants such as MTBE and TBA. Microcosm studies demonstrated that MTBE and TBA may be biodegradable under oxic and nearly all anoxic conditions, although results of various studies are often contradictory, which suggests that site-specific conditions are important parameters. So far, TBA degradation has not been shown under methanogenic conditions and it is currently widely accepted that TBA is a recalcitrant dead-end product of MTBE under these conditions. Reliable in situ degradation rates for MTBE and TBA under various geochemical conditions are not yet available. Furthermore, degradation pathways under anoxic conditions have not yet been elucidated. All pure cultures capable of MTBE or TBA degradation isolated so far use oxygen as terminal electron acceptor. In general, compared with hydrocarbons present in gasoline, fuel oxygenates biodegrade much slower, if at all. The presence of MTBE and related compounds in groundwater therefore frequently limits the use of in situ biodegradation as remediation option at gasoline-contaminated sites. Though degradation of MTBE and TBA in field studies has been reported under oxic

  4. Use of spin labels to evaluate effects of cold shock and osmolality on sperm

    Energy Technology Data Exchange (ETDEWEB)

    Hammerstedt, R.H.; Keith, A.D.; Snipes, W.; Amann, R.P.; Arruda, D.; Griel, L.C. Jr.

    1978-05-01

    Spin labels were used to evaluate the effects of butylated hydroxytoluene (BHT), rapid cooling to 0/sup 0/C and osmolality on the integrity of sperm membranes. In vitro incubation of rabbit sperm with 0.5 mM BHT prior to artificial insemination did not alter the fertilizing ability of the sperm. Sperm from 6 species were ranked in terms of susceptibility to membrane damage caused by rapid cooling to 0/sup 0/C. The integrity of bull and ram sperm membranes was destroyed by the rapid cooling; BHT protected membranes of these spermatozoa from cold-induced lysis. Boar sperm membranes were porous after rapid cooling and BHT did not prevent this membrane damage. Membranes of rabbit and rooster sperm were not damaged by rapid cooling to 0/sup 0/C. Stallion sperm could not be analyzed because their membranes were altered by addition of reagents necessary to use the technique. The responses of bull, ram and rabbit sperm membranes to hyper- and hypo-osmotic conditions were determined. Hypotonic treatment (less than 200 mOsm) resulted in a 50 percent expansion of the volume of the aqueous compartment of sperm while hypertonic (700 mOsm) conditions compressed the volume of the aqueous compartment to 25 to 30 percent of the volume measured at 300 mOsm. Bull sperm, but not rabbit or ram sperm, responded as ''perfect osmometers'' between 300 and 700 mOsm.

  5. Antioxidant Activity of Protein Hydrolysates Obtained from Common Carp (Cyprinus carpio) Discarded Roe

    DEFF Research Database (Denmark)

    Ghelichi, Sakhi; Sørensen, Ann-Dorit Moltke; García Moreno, Pedro Jesús;

    Lipid oxidation represents a severe challenge in food engineering because it deteriorates quality of foods, especially those containing high contents of polyunsaturated fatty acids (PUFAs). One way to overcome this barrier is application of synthetic antioxidants such as butylated hydroxyanisole...... (BHA), butylated hydroxytoluene (BHT), propyl gallate (PG), and tertiary butylhydroquinone (TBHQ) in PUFA-rich foods. However, recently there have been concerns over health-related risks posed by these synthetic agents. Therefore, obtaining safe antioxidants from natural sources, especially those which...... are discarded with no use, with potency to retard lipid oxidation has gained sizable attention. Therefore, the present study aimed at obtaining “green” antioxidants from discarded common carp roe via the so-called hydrolysis process by using alcalase and determining their antioxidant activity both in vitro...

  6. Antioxidant activity of wild edible plants in the Black Sea Region of Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Ozen, T.

    2010-07-01

    The anti oxidative activity of the 80% ethanol extract obtained from eleven commonly consumed wild edible plants was determined according to the phospho molybdenum method, reducing power, metal chelating, superoxide anion and free radical scavenging activity and compared to standard compounds such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and trolox. Total phenolic compounds, flavonoids, and anthocyanins in the extracts were also measured. Trachystemon orientalis, Vaccinium mrytillus, Rumex acetosella Polygonum amphibium, Beta vulgaris, and Similax Excelsa had the highest antioxidant capacities. Overall results showed that these plants can serve as good sources of bioactive polyphenols in the human diet and can be regarded as good candidates for nutritional supplement formulations due to their high concentrations of total phenolic compounds, flavonoids and anthocyanins as well as their strong antioxidant activity. (Author) 42 refs.

  7. Evaluation of the antioxidant properties of Mediterranean and tropical fruits compared with common food additives.

    Science.gov (United States)

    Murcia, M A; Jiménez, A M; Martínez-Tomé, M

    2001-12-01

    Several Mediterranean and tropical fruits have been analyzed in order to assess their antioxidant activity compared with that of common food additives (butylated hydroxyanisole [BHA], butylated hydroxytoluene [BHT] and propyl gallate). Among Mediterranean fruits, red grape and plum were more effective (P plum > apricot > white grape > melon > red grape > mandarin > watermelon > peach > medlar > apple > orange > cherry > strawberry. However, the four varieties of pear were poor scavengers (P lime > passiflora > kumquat > avocado > pineapple > physalis > papaya fruit > carambola > mango > banana. All Mediterranean fruits showed an effect on hydrogen peroxide except peach. Tropical fruits also had a strong effect on hydrogen peroxide except avocado, which had no effect. The effect of Mediterranean and tropical fruits on the protection factor of refined olive oil, analyzed by the Rancimat method and compared with common food additives, was clear. Watermelon conferred a significantly (P < 0.05) greater protection than the other Mediterranean fruits. Among tropical fruits, physalis had the most stabilizing effect.

  8. In vitro antioxidant profiles of some flavonoids

    Science.gov (United States)

    Aksoy, Mine; Gülçin, Ilhami; Küfrevioǧlu, Ö. Irfan

    2016-04-01

    Baicalin ((2S,3S,4S,5R,6S)-6-(5,6-dihydroxy-4-oxo-2-phenyl-chromen-7-yl)oxy-3,4,5-trihydroxy-tetrahydropyran-2-carboxylic acid) and baicalein (5,6,7-trihydroxyflavone) are a flavone, a type of flavonoid. Baicalin is the glucuronide of baicalein. Phlorizin, or phloridzin is a naturally occurring flavonoid produced in some plants. It belongs to the group of dihydrochalcones. In this study, we investigated the in vitro antioxidant properties of baicalin, baicalein and phloridzin using different methods including ferric ion (Fe3+) reducing power, cupric ion (Cu2+) reducing power (CUPRAC method), reduction of Fe3+-TPTZ complex, 1,1-diphenyl-2-picrylhydrazyl free radicals (DPPH.) scavenging, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid radicals (ABTS.+) scavenging activities. Also, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT) and α-Tocopherol were used as standard antioxidants.

  9. DIVERSIDAD DE ORQUÍDEAS EPÍFITAS EN UN BOSQUE HÚMEDO TROPICAL (bh-T DEL DEPARTAMENTO DEL CHOCÓ

    Directory of Open Access Journals (Sweden)

    Pino Benitez Nayive

    2010-08-01

    Full Text Available

    Se evaluó la diversidad de orquídeas epífitas en un bosque húmedo tropical (bh-T, perteneciente al corregimiento de Tutunendo (Quibdó. En él fueron establecidas tres zonas de acuerdo al grado de intervención del bosque: poco (300 m2, medio (400 m2 y altamente intervenido (300 m2; dentro de estos fueron registrados 66 forófitos con un DAP ≥ a 20 cm, en los cuales se muestrearon las orquídeas huéspedes, obteniendo un registro total de 1.348 individuos, distribuidos en 49 especies y 20 géneros. Los géneros más representativos en número de especies fueron Maxillaria (11 y Dichaea (5. Según el índice de Shannon-Weiner, se aprecia una alta diversidad de orquídeas epífitas en el área de estudio (H’=3.30. En cuanto a las zonas de acuerdo al grado de intervención, el bosque medio y el poco intervenido fueron los más altos en diversidad, sin embargo, el altamente intervenido, donde se da el tipo de cultivo de tumba y siembra y la extracción maderera es constante, presentó los más bajos resultados. Según la prueba de Kruskal-Wallis, estas zonas presentaron diferencias significativas (P<0.05 en cuanto a la riqueza y abundancia de especies registradas. Evidentemente, la alta diversidad de este grupo de plantas puede

  10. Pressure-induced crystallization of 1-butyl-3-methylimidazolium hexafluorophosphate

    Science.gov (United States)

    Shigemi, Machiko; Takekiyo, Takahiro; Abe, Hiroshi; Yoshimura, Yukihiro

    2013-03-01

    We have investigated the pressure-induced crystallization of 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF6]) associated with the conformational changes of [bmim]+ by Raman spectroscopy. [bmim]+ has trans-trans and gauche-trans (GT) conformers of the butyl side chain at ambient pressure. Our result revealed that liquid to solid-phase transition occurs at 0.2-0.4 GPa region, where the GT conformer becomes dominant. We found that the GT dominant state continues up to 4 GPa.

  11. Conversion of Lignocellulosic Biomass to Ethanol and Butyl Acrylate

    Energy Technology Data Exchange (ETDEWEB)

    Binder, Thomas [Archer Daniels Midland Company, Decatur, IL (United States); Erpelding, Michael [Archer Daniels Midland Company, Decatur, IL (United States); Schmid, Josef [Archer Daniels Midland Company, Decatur, IL (United States); Chin, Andrew [Archer Daniels Midland Company, Decatur, IL (United States); Sammons, Rhea [Archer Daniels Midland Company, Decatur, IL (United States); Rockafellow, Erin [Archer Daniels Midland Company, Decatur, IL (United States)

    2015-04-10

    Conversion of Lignocellulosic Biomass to Ethanol and Butyl Acrylate. The purpose of Archer Daniels Midlands Integrated Biorefinery (IBR) was to demonstrate a modified acetosolv process on corn stover. It would show the fractionation of crop residue to distinct fractions of cellulose, hemicellulose, and lignin. The cellulose and hemicellulose fractions would be further converted to ethanol as the primary product and a fraction of the sugars would be catalytically converted to acrylic acid, with butyl acrylate the final product. These primary steps have been demonstrated.

  12. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) ...

    Science.gov (United States)

    The IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) was released for external peer review in April 2017. EPA’s Science Advisory Board’s (SAB) Chemical Assessment Advisory Committee (CAAC) will conduct a peer review of the scientific basis supporting the ETBE assessment and release a final report of their review. Information regarding the peer review can be found on the SAB website. EPA is conducting an Integrated Risk Information System (IRIS) health assessment for Ethyl Tertiary Butyl Ether (ETBE). The outcome of this project is a Toxicological Review and IRIS Summary for ETBE that will be entered into the IRIS database.

  13. A Study of the Teratogenicity of Butylated Hydroxyanisole on Rabbits

    DEFF Research Database (Denmark)

    Hansen, Ernst; Meyer, Otto A.

    1978-01-01

    A teratogenicity study on butylated hydroxyanisole (BHA) was carried out in SPF New Zealand White rabbits. BHA was given by gavage from day 7–18 of the gestation period in doses of 0, 50, 200 and 400 mg/kg body wt./day. The fetuses were removed on day 28. No effect related to the treatment with BHA...

  14. 27 CFR 21.100 - n-Butyl alcohol.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false n-Butyl alcohol. 21.100 Section 21.100 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants §...

  15. 27 CFR 21.101 - tert-Butyl alcohol.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false tert-Butyl alcohol. 21.101 Section 21.101 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants §...

  16. Enhanced Heterogeneous Catalytic Conversion of Furfuryl Alcohol into Butyl Levulinate

    NARCIS (Netherlands)

    Carà, P.D..; Ciriminna, R.; Shiju, N.R.; Rothenberg, G.; Pagliaro, M.

    2014-01-01

    We study the catalytic condensation of furfuryl alcohol with 1-butanol to butyl levulinate. A screening of several commercial and as-synthesized solid acid catalysts shows that propylsulfonic acid-functionalized mesoporous silica outperforms the state-of-the-art phosphotungstate acid catalysts. The

  17. 76 FR 82152 - Cyhalofop-butyl; Pesticide Tolerances

    Science.gov (United States)

    2011-12-30

    ... observed following subchronic or chronic exposure to cyhalofop-butyl included hyperplasia of the stomach... exposure from drinking water. The Agency used screening level water exposure models in the dietary exposure...://www.epa.gov/oppefed1/models/water/index.htm . Based on the Tier 1 Rice Model and...

  18. Electrical Properties of n-Butyl Acrylate-Grafted Polyethylene

    Energy Technology Data Exchange (ETDEWEB)

    Lee, C.R.; Oh, W.J.; Suh, K.S. [Korea University (Korea, Republic of)

    1997-04-01

    The electrical properties of n-butyl acrylate-grafted polyethylene (PE-g-nBA) were investigated. In PE-g-nBA, hetero charge founded in LDPE slightly increased due to the nBA grafting. Conduction currents decreased with the increase of nBA graft ratio. AC breakdown strength increased and water treeing length decreased with the increase of graft ratio in PE-g-nBA. (author). 4 refs., 6 figs.

  19. Tris(tert-butyl isocyanide-κCcarbonylnickel(0

    Directory of Open Access Journals (Sweden)

    Wolfgang Imhof

    2008-08-01

    Full Text Available The title compound, [Ni(C5H9N3(CO], was prepared from Ni(CO4 and a tenfold excess of tert-butyl isocyanide. It crystallizes with two symmetry-independent molecules per asymmetric unit. The central Ni atom of each independent molecule has a nearly perfect tetrahedral coordination environment, comprising one carbon monoxide and three isocyanide ligands. The title compound is the first structurally characterized Ni0 compound with a mixed CO/RNC coordination.

  20. POLYMERIZATION OF BUTYL METHACRYLATE BY IRON PYRIDINEBISIMINE COMPLEXES

    Institute of Scientific and Technical Information of China (English)

    Jing-yu Liu; Yan-guo Li; Yi Zheng; Yue-sheng Li

    2005-01-01

    Fe(Ⅱ) pyridinebisimine complexes activated with trialkylaluminium or modified methylaluminoxane (MMAO) as catalysts were employed for the polymerization of butyl methacrylate (BMA). Polymer yields, catalytic activities and molecular weights as well as molecular weight distributions of BMA can be controlled over a wide range by varying the reaction parameters such as cocatalyst, A1/Fe molar ratio, monomer/catalyst molar ratio, monomer concentration and reaction yield could reach 99.1% under optimum condition.

  1. Enantioselective degradation and chiral stability of the herbicide fluazifop-butyl in soil and water.

    Science.gov (United States)

    Qi, Yanli; Liu, Donghui; Luo, Mai; Jing, Xu; Wang, Peng; Zhou, Zhiqiang

    2016-03-01

    The stereoselective degradation and transformation of the enantiomers of the herbicide fluazifop-butyl in soil and water were studied to investigate the environmental behavior and chiral stability of the optical pure product. Its main chiral metabolite fluazifop was also monitored. LC/MS/MS with Chiralpak IC chiral column was used to separate the enantiomers of fluazifop-butyl and fluazifop. Validated enantioselective residue analysis methods were established with recoveries ranging from 77.1 to 115.4% and RSDs from 0.85 to 8.9% for the enantiomers. It was found the dissipation of fluazifop-butyl was rapid in the three studied soils (Beijing, Harbin and Anhui soil), and the degradation half-lives of the enantiomers ranged from 0.136 to 2.7 d. Enantioselective degradations were found in two soils. In Beijing soil, R-fluazifop-butyl was preferentially degraded leading to relative enrichment of S-enantiomer, but in Anhui soil, S-fluazifop-butyl dissipated faster. There was no conversion of the R-fluazifop-butyl into S-fluazifop-butyl or vice versa in the soils. The formation of fluazifop in the soils was rapidly accompanied with the fast degradation of fluazifop-butyl, and the enantioselectivity and the transformation of S-fluazifop to R-fluazifop were found. The degradation of fluazifop-butyl in water was also quick, with half-lives of the enantiomers ranging from 0.34 to 2.52 d, and there was no significant enantioselectivity of the degradation of fluazifop-butyl and the formation of fluazifop. The effects of pH on the degradation showed fluazifop-butyl enantiomers degraded faster in alkaline conditions. This study showed an evidence of enantioselective behavior and enantiomerization of the chiral herbicide fluazifop-butyl.

  2. Inducing PLA/starch compatibility through butyl-etherification of waxy and high amylose starch.

    Science.gov (United States)

    Wokadala, Obiro Cuthbert; Emmambux, Naushad Mohammad; Ray, Suprakas Sinha

    2014-11-04

    In this study, waxy and high amylose starches were modified through butyl-etherification to facilitate compatibility with polylactide (PLA). Fourier transform infrared spectroscopy, proton nuclear magnetic resonance spectroscopy and wettability tests showed that hydrophobic butyl-etherified waxy and high amylose starches were obtained with degree of substitution values of 2.0 and 2.1, respectively. Differential scanning calorimetry, tensile testing, and scanning electron microscopy (SEM) demonstrated improved PLA/starch compatibility for both waxy and high amylose starch after butyl-etherification. The PLA/butyl-etherified waxy and high amylose starch composite films had higher tensile strength and elongation at break compared to PLA/non-butyl-etherified composite films. The morphological study using SEM showed that PLA/butyl-etherified waxy starch composites had a more homogenous microstructure compared to PLA/butyl-etherified high amylose starch composites. Thermogravimetric analysis showed that PLA/starch composite thermal stability decreased with starch butyl-etherification for both waxy and high amylose starches. This study mainly demonstrates that PLA/starch compatibility can be improved through starch butyl-etherification.

  3. Polyphenolic rich traditional plants and teas improve lipid stability in food test systems.

    Science.gov (United States)

    Ramsaha, Srishti; Aumjaud, B Esha; Neergheen-Bhujun, Vidushi S; Bahorun, Theeshan

    2015-02-01

    The deleterious effects of lipid autoxidation are of major concern to the food industry and can be prevented by food antioxidants. In this vein, the phenolic contents and antioxidant potential of traditional plants of Mauritius such as P. betle L. (Piperaceae), M. koenigii L. Sprengel. (Rutaceae), O. gratissimum L. (Lamiaceae), O. tenuiflorum L. (Lamiaceae), and commercially available Mauritian green and black teas were evaluated. Their ferric reducing antioxidant power (FRAP) were compared to that of butylated hydroxytoluene (BHT) with the following order of potency: BHT > "Natural" commercial green tea > "Black Label" commercial black tea > O. gratissimum > P. betle > O. tenuiflorum > M. koenigii. The trolox equivalent antioxidant capacity (TEAC) assay reflected a similar antioxidative order for BHT and "Natural" commercial green tea, with however P. betle, O. tenuiflorum and O. gratissimum exhibiting higher activities than "Black Label" commercial black tea and M. koenigii. Based on their potent antioxidant capacity, P. betle (0.2 % m/m) and O. tenuiflorum (0.2 % m/m) extracts, and green tea (0.1 % m/m) infusate were compared with BHT (0.02 % m/m) on their ability to retard lipid oxidation in unstripped sunflower oil and mayonnaise during storage at 40 °C. P. betle and green tea were more effective than BHT in both food systems. Moreover, odour evaluation by a sensory panel showed that the plant extracts and green tea infusate effectively delayed the development of rancid odours in unstripped sunflower oil and mayonnaise (p < 0.05).

  4. tert-Butyl N-(thiophen-2-ylcarbamate

    Directory of Open Access Journals (Sweden)

    Gene C. Hsu

    2013-09-01

    Full Text Available In the title compound, C9H13NO2S, the dihedral angle between the thiophene ring and the carbamate group is 15.79 (14°. In the crystal structure, intramolecular C—H...O interactions in tandem with the tert-butyl groups render the packing of adjacent molecules in the [001] direction nearly perpendicular [the angle between adjacent thiophene rings is 74.83 (7°]. An intermolecular N—H...O hydrogen bond gives rise to a chain extending along [001]. The crystal studied was found to be a racemic twin.

  5. Effect of natural and synthetic antioxidants on oxidative stability of FAMEs obtained from hevea brasiliensis

    Institute of Scientific and Technical Information of China (English)

    S.Nivetha; D.Vetha; Roy

    2013-01-01

    Biodiesel(fatty acid alkyl esters),an alternate to fossil fuel,has the tendency of autoxidation and hence requires antioxidants for long term storage.The influence of synthetic and natural antioxidants on the oxidative stability was analysed for fresh FAMEs(fatty acid methyl esters)obtained from hevea brasiliensis at 140 C.Higher activity was observed for synthetic antioxidants following the order of GA>BHT>DTBP>Q>GT-M>PH-M>GT-C,whereas the oxidative stability of stored FAMEs samples measured at 110 C reveals a nearly inverse trend.Storage stability was tested for the FAMEs obtained from hevea brasiliensis stored at 30 C,after addition of synthetic and natural antioxidants—butylated hydroxytoluene(BHT),2,6-di-tert-butylphenol(DTBP),quercetin(Q),gallic acid(GA),methanol extracts from green tea(GTM),pomegranate hull(PH-M),and chloroform extract of green tea(GT-C).Antioxidant activities above 1500 ppm was in the order of DTBP>BHT>GA>GT-C>GT-M>Q>PH-M.Synthetic antioxidants have been found more efficient to improve the storage stability of FAMEs obtained from hevea brasiliensis.DTBP in particular has the highest protection factor.

  6. Mycoflora and Ochratoxin A Control in Wheat Grain Using Natural Extracts Obtained from Wine Industry By-Products

    Directory of Open Access Journals (Sweden)

    Renata-Maria Sumalan

    2012-04-01

    Full Text Available The aim of this study was to evaluate the effect of some natural extracts obtained from grape pomace (GPE and grape seeds (GSE as compared to a synthetic food, antioxidant-butylated hydroxytoluene (BHT, in order to control fungal population and ochratoxin A (OTA production in naturally contaminated wheat. The results showed that the addition of these extracts was efficient with OTA content decreasing. On treatment with these extracts the loss of OTA content after 14 days was in the range 7.8–28.3% relative to the control sample, but increased up to 26.48–37% after 28 days. The highest loss in OTA content was recorded for treatment with GPE at the 500 ppm level. Regarding the fungal development, the obtained results show that the total fungal populations were significantly reduced by using natural extracts. The most efficient extract was GPE. Both BHT and GPE inhibit the growth of Penicillium verrrucosum, for all doses, but less with Aspergillus genera. GPE affects the growth of other types of moulds such as Rhizopus microsporus, Fusarium graminearum, Alternaria infectoria and Cladosporium herbarum. Our data suggested that GPE and GSE are able to provide fungicidal and fungistatic protection and to control the OTA accumulation in wheat, at least in a similar manner to BHT.

  7. Influence of peanut skin extract on shelf-life of sheep patties

    Institute of Scientific and Technical Information of China (English)

    Paulo Eduardo Sichetti Munekata; Rafaella de Paula Paseto Fernandes; Mariza Pires de Melo; Marco Antonio Trindade; José Manuel Lorenzo

    2016-01-01

    Objective: To evaluate the phenolic profile and antioxidant activity in vitro of peanut skin extract(PSE) and effect of PSE on characteristics of sheep patties during storage.Methods: PSE phenolic profile was evaluated in LC–MS analysis and by total phenolic content, 1,1-diphenyl-2-picrylhydrazyl radical scavenging capacity and ferric reducing/antioxidant power. Patties elaborated with sheep meat were packaged in modified atmosphere and storage at(2 ± 1)C. The analyses were performed every 5 days for 20 days on microbial counts, physico-chemical properties, lipid oxidation, protein stability and sensory characteristics.Results: The major group of phenolic compounds in PSE was the proanthocyanidins followed by other flavonoids, which are related to potential phenolic content and antioxidant activity. The addition of PSE and butyl hydroxytoluene(BHT) reduced the microbial counts during the storage time, caused reduction on the loss of redness and sensory properties over time. The lipid and protein oxidation in sheep patties was effectively inhibited by PSE and BHT.Conclusions: The present results showed the potential application of PSE as a natural alternative to replace synthetic antioxidants(BHT) for increasing the quality and extending the shelf-life of sheep patties.

  8. Influence of peanut skin extract on shelf-life of sheep patties

    Institute of Scientific and Technical Information of China (English)

    Mariza Pires de Melo; Marco Antonio Trindade; Jose Manuel Lorenzo

    2016-01-01

    Objective: To evaluate the phenolic profile and antioxidant activity in vitro of peanut skin extract (PSE) and effect of PSE on characteristics of sheep patties during storage. Methods: PSE phenolic profile was evaluated in LC–MS analysis and by total phenolic content, 1,1-diphenyl-2-picrylhydrazyl radical scavenging capacity and ferric reducing/antioxidant power. Patties elaborated with sheep meat were packaged in modified at-mosphere and storage at (2 ± 1) ?C. The analyses were performed every 5 days for 20 days on microbial counts, physico-chemical properties, lipid oxidation, protein stability and sensory characteristics. Results: The major group of phenolic compounds in PSE was the proanthocyanidins followed by other flavonoids, which are related to potential phenolic content and anti-oxidant activity. The addition of PSE and butyl hydroxytoluene (BHT) reduced the mi-crobial counts during the storage time, caused reduction on the loss of redness and sensory properties over time. The lipid and protein oxidation in sheep patties was effectively inhibited by PSE and BHT. Conclusions: The present results showed the potential application of PSE as a natural alternative to replace synthetic antioxidants (BHT) for increasing the quality and extending the shelf-life of sheep patties.

  9. Evaluation of the Antimicrobial and Antioxidant Activities of Origanum dictamnus Extracts before and after Encapsulation in Liposomes

    Directory of Open Access Journals (Sweden)

    John Tsaknis

    2007-05-01

    Full Text Available The antioxidant and antimicrobial activity of methanol or dichloromethane extracts of O. dictamnus, produced from wild and organic cultivated specimens, were determined. The Rancimat and malondialdehyde (MDA by HPLC methods were used to measure the antioxidant action, in comparison with that of the common commercial antioxidants butylated hydroxytoluene (BHT and α-tocopherol. The extracts that presented high antioxidant activity were encapsulated in liposomes and their antioxidant action was again estimated using differential scanning calorimetry (DSC. Thermaloxidative decomposition of the samples (pure liposomes and encapsulated extracts and the modification of the main transition temperature for the lipid mixture and the splitting of the calorimetric peak in the presence of the antioxidants were also studied by the DSC method. All extracts showed antioxidant and antimicrobial activities. Their action proved superior to α-tocopherol. The methanol extract of organic cultivated O. dictamnus (240 ppm showed higher activity than butylated hydroxytoluene. After encapsulation in liposomes the antioxidant as well as antimicrobial activities proved to be higher than those of the same extracts in pure form.

  10. Methyltert-butyl Ether (MTBE Degradation by a Microbial Consortium

    Directory of Open Access Journals (Sweden)

    S. B. Mortazavi

    2005-01-01

    Full Text Available Methyl tert-butyl ether (MTBE is added to reformulated gasoline to meet the 1990 Clean Air Act directives. Widespread use of MTBE in gasoline has resulted in groundwater contamination. Because of its undesirable effects on drinking water and ecologically harmful effects, MTBE removal has become a public health and environmental concern. In this study, we have isolated a mixed bacterial culture which is capable of degrading the MTBE as a sole carbon and energy source. This consortium was developed from mixed urban and petrochemical activated sludge after 4 month's enrichment. Enrichment was conducted in batch reactor, fitted with a screw cap and butyl rubber septum. MTBE concentration was measured in head space by gas chromatography. Degradation was determined by MTBE removal. MTBE biodegradation was depended to Dissolved Oxygen (DO concentration and not affected by the changes in concentration of trace element solution or other stimulator Substances. Degradation rates were nearly 1.478 mg MTBE h-1 g-1 (wet biomass and didn't change with MTBE concentration (up 500 mg L-1.

  11. Antisickling activity of butyl stearate isolated from Ocimum basilicum (Lamiaceae)

    Institute of Scientific and Technical Information of China (English)

    Dorothe Dinangayi Tshilanda; Pius Tshimankinda Mpiana; Damase Nguwo Vele Onyamboko; Blaise Mavinga Mbala; Koto-te-Nyiwa Ngbolua; Damien Sha Tshibey Tshibangu; Matthieu Kokengo Bokolo; Kalulu Muzele Taba; Teddy Kabeya Kasonga

    2014-01-01

    Objective: To perform phytochemical analyses on the leaves of Ocimum basilicum L. (O. basilicum), to elucidate the structure of isolate and then perform the antisickling activity on the crude extract and on the isolate. Methods:The Emmel test performed on the acidified methanolic extract of this plant was used to evaluate the antisickling activity. The structure characterization of the active compound was performed using chromatographic techniques for the separation and the spectroscopic ones for structure elucidation (1H-NMR, 13C-NMR, COSY, HMBC). Results: The chemical screening on the crude extract revealed the presence of polyphenols (flavonoids, anthocyanins, leucoanthocyanins, tannins, quinones) alkaloids, saponins, triterpenoids and steroids. The obtained extract after evaporation yielded 34.50 g (11.5%) out of 300 g of powdered leaves of O. basilicum. The acidified methanolic extract and butyl stearate showed an interesting antisickling activity. Conclusions:The acidified methanolic extract and butyl stearate from O. basilicum displayed a good antisickling activity. To the best of our knowledge, this is the first time to report the antisickling activity of this compound in this plant. The synthesized compound presented the same spectroscopic characteristics than the natural one and the antisickling activities of its derivatives are understudying.

  12. Stabilization of Neem Oil Biodiesel with Corn Silk Extract during Long-term Storage.

    Science.gov (United States)

    Ali, Rehab Farouk M; El-Anany, Ayman M

    2017-02-01

    The current study aimed to evaluate the antioxidant efficiency of different extracts of corn silk. In addition, the impact of corn silk extract on oxidative stability of neem biodiesel during storage was studied. The highest phenolics, DPPH radical scavenging and reducing power activities were recorded for methanol-water extract. The longest oxidation stability (10 h) was observed for biodiesel samples blended with 1000 ppm of corn silk extract (CSE). At the end of storage period the induction time of biodiesel samples mixed with 1000 ppm of CSE or butylated hydroxytoluene (BHT) were about 6.72 and 5.63 times as high as in biodiesel samples without antioxidants. Biodiesel samples blended with 1000 ppm of CSE had the lowest acidity at the end of storage period. Peroxide value of biodiesel samples containing 1000 ppm of CSE was about 4.28 times as low as in control sample without antioxidants.

  13. Effectiveness of various phenolic compounds (commercial and non-commercial) on biodiesel oxidation stability

    Energy Technology Data Exchange (ETDEWEB)

    Anastasakos, A.; Deligiannis, A.; Dodos, G.S.; Karonis, D.; Zannikos, F. [National Technical Univ. of Athens (Greece). Lab. of Fuels Technology and Lubricants

    2013-06-01

    This study investigates the effectiveness of seven phenolic compounds, including pyrogallol (PY), butylated hydroxytoluene (BHT), 2,5-di-tert-butylhydroquinone (DTBHQ), 4-tert-Butylcatechol (TBC), 2,5- bis(dimethylaminomethyl) hydroquinone, 2,5-bis(piperidinomethyl) hydroquinone and 2,5-bis(morpholinomethyl) hydroquinone on the oxidation stability of sunflower and soybean oil methyl esters. The seven phenolic compounds were dissolved in the base fuels at the same concentration levels, i.e., 200, 600, 800, 1000 and 1200 ppm. The oxidation stability measurements were carried out by employing a Rancimat accelerated oxidation unit according to EN 14214. Most of the antioxidants had a measurable positive impact on the oxidation stability in all concentrations of the additives. (orig.)

  14. Antioxidant activities of bioactive components from Xylaria gracillima in submerged culture%细小炭角菌深层发酵产物的抗氧化活性研究

    Institute of Scientific and Technical Information of China (English)

    李赛飞; 文华安

    2008-01-01

    The antioxidant potency of components from Xylaria gracillima in submerged culture was investigated,employing various established in vitro systems,such as superoxide(O2.-)and hydroxyl(OH)radical scavenging,reducing power,and ferrous ion chelating ability.Tocopherol(Ve),butylated hydroxytoluene (BHT)and ethylenediaminetetraacetic acid(EDTA)were used as positive controls.According to the results,components from X.gracillima in submerged culture showed significant effect on ferrous ion chelating ability,O2.-and .OH radical scavenging ability at the range of concentration tested,and their highest antioxidant activities reached 89.72%,70.90% and 77.46% respectively.The components also showed positive results of reducing power.These in vitro results suggested the possibility that components from X.gracillima in submerged culture could be effectively employed as an ingredient in healthy or functional food.

  15. Effect of pomegranate peel extract on lipid and protein oxidation in beef meatballs during refrigerated storage.

    Science.gov (United States)

    Turgut, Sebahattin Serhat; Soyer, Ayla; Işıkçı, Fatma

    2016-06-01

    Antioxidant effect of pomegranate peel extract (PE) to retard lipid and protein oxidation was investigated in meatballs during refrigerated storage at 4±1°C. Concentrated lyophilised water extract of pomegranate peel was incorporated into freshly minced beef meat at 0.5% and 1% concentrations and compared with 0.01% butylated hydroxytoluene (BHT) as a reference and control (without any antioxidant). PE showed high phenolic content and antioxidant activity. In PE added samples, thiobarbituric acid reactive substances (TBARS) value, peroxide formation, loss of sulfhydryl groups and formation of protein carbonyls were lower than control (P<0.01) after 8 days of storage. Sensory evaluation with respect to colour and rancid odour revealed that PE incorporation in meatballs prolonged the refrigerated storage up to 8 days. Addition of both 0.5 and 1% PE in meatballs reduced lipid and protein oxidation and improved sensory scores. These results indicated that PE was effective on retarding lipid and protein oxidation.

  16. 76 FR 38026 - Diethylene Glycol Mono Butyl Ether; Exemption From the Requirement of a Tolerance

    Science.gov (United States)

    2011-06-29

    ... butyl ether, also a glycol ether differing in only one ethyl group from DEGBE. These data were used to... monobutyl ether, also a glycol ether differing only in one ethyl group. This data was used to assess the... AGENCY 40 CFR Part 180 Diethylene Glycol Mono Butyl Ether; Exemption From the Requirement of a...

  17. Synthesis of Highly Porous Poly(tert-butyl acrylate)-b-polysulfone-b-poly(tert-butyl acrylate) Asymmetric Membranes

    KAUST Repository

    Xie, Yihui

    2016-03-24

    For the first time, self-assembly and non-solvent induced phase separation was applied to polysulfone-based linear block copolymers, reaching mechanical stability much higher than other block copolymers membranes used in this method, which were mainly based on polystyrene blocks. Poly(tert-butyl acrylate)-b-polysulfone-b-poly(tert-butyl acrylate) (PtBA30k-b-PSU14k-b-PtBA30k) with a low polydispersity of 1.4 was synthesized by combining step-growth condensation and RAFT polymerization. Various advanced electron microscopies revealed that PtBA30k-b-PSU14k-b-PtBA30k assembles into worm-like cylindrical micelles in DMAc and adopts a “flower-like” arrangement with the PSU central block forming the shell. Computational modeling described the mechanism of micelle formation and morphological transition. Asymmetric nanostructured membranes were obtained with a highly porous interconnected skin layer and a sublayer with finger-like macrovoids. Ultrafiltration tests confirmed a water permeance of 555 L m-2 h-1 bar-1 with molecular weight cut-off of 28 kg/mol. PtBA segments on the membrane surface were then hydrolyzed and complexed with metals, leading to cross-linking and enhancement of antibacterial capability.

  18. Vapor Pressures of Di-n-Butyl Phthalate and Di-iso-Butyl Hexahydrophthalate at Reduced Pressures

    Institute of Scientific and Technical Information of China (English)

    齐欣; 徐立勇; 高正红; 刘志华

    2004-01-01

    In this paper the measured values of the vapor pressures by ebulliometer method of two important maleic anhydride recovery solvents, di-n-butyl phthalate (DBP) and di-iso-butyl hexahydrophthalate (DIBE), between 0.63-17.79 kPa and 0.49-30.95 kPa,are reported respectively.A comparison of the data of DBP with the published data has been made, which shows good consistency. For the convenient use of these vapor pressures, Cragoe equation, Antoine equation and Kirchhoff equation are selected to correlate them. The correlating results show that Antoine equation is the best one of the three equations to fit for the vapor pressures of the two solvents. According to Clausius-Clapeyron equation, the linear relationship between natural logarithm of pressure and reciprocal of temperature is used to calculate the molar latent heats of evaporation of the two organic solvents. The molar latent heats of evaporation of DBP and DIBE are 75.1 kJ/mol and 67.7 kJ/mol, respectively.

  19. Recovering/recycling of butyl and halogenated butyl rubber via ionizing radiation; Recuperacao/reciclagem de compostos de borrachas butilica e halobutilica por meio de radiacao ionizante

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Sandra Regina Scagliusi

    2013-07-01

    Polymeric materials (plastics and rubbers) attain a continuous and raising proportion of urban and industrial scraps discarded in landfills; their impact on environment are more and more concerning. The implementation of new technologies in order to reduce impacts of plastic waste on the environment, at an effective cost, proved to be a great problem, due to inherent complexity for polymers re-using. Ionizing radiation is capable to modify structure and properties of polymeric material. Butyl and halobutyl rubbers have been used within a comprehensive scale, applications such as tires spare parts and diverse artifacts. The major high energy photon effect, as gamma-rays in butyl and halo butyl rubbers consists in free-radicals generation along changes in mechanical properties.This work aims to the development of controlled degradation processes (devulcanization) of butyl and halo butyl (chlorine and bromine) rubbers, in order to characterize their availability for transformation and modification of properties. Experimental results obtained showed that butyl and halobutyl rubbers,irradiated at 25 kGy and further sheared, are able to be used as an initial point for mixtures with pristine. (author)

  20. Antioxidants in aqueous extract of Myristica fragrans (Houtt.) suppress mitosis and cyclophosphamide-induced chromosomal aberrations in Allium cepa L. cells.

    Science.gov (United States)

    Akinboro, Akeem; Mohamed, Kamaruzaman Bin; Asmawi, Mohd Zaini; Sulaiman, Shaida Fariza; Sofiman, Othman Ahmad

    2011-11-01

    In this study, freeze-dried water extract from the leaves of Myristica fragrans (Houtt.) was tested for mutagenic and antimutagenic potentials using the Allium cepa assay. Freeze-dried water extract alone and its combination with cyclophosphamide (CP) (50 mg/kg) were separately dissolved in tap water at 500, 1000, 2000, and 4000 mg/kg. Onions (A. cepa) were suspended in the solutions and controls for 48 h in the dark. Root tips were prepared for microscopic evaluation. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) free radicals' scavenging power of the extract was tested using butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) as standards. Water extract of Myristica fragrans scavenged free radicals better than BHA, but worse than BHT. The extract alone, as well as in combination with CP suppressed cell division, and induced chromosomal aberrations that were insignificantly different from the negative control (P ≤ 0.05). However, cytotoxic and mutagenic actions of CP were considerably suppressed. The observed effects on cell division and chromosomes of A. cepa may be principally connected to the antioxidant properties of the extract. The obtained results suggest mitodepressive and antimutagenic potentials of water extract of the leaves of M. fragrans as desirable properties of a promising anticancer agent.

  1. Antioxidants in aqueous extract of Myristicafragrans (Houtt.) suppress mitosis and cyclophosphamide-induced chromosomal aberrations in Allium cepa L.cells

    Institute of Scientific and Technical Information of China (English)

    Akeem AKINBORO; Kamaruzaman Bin MOHAMED; Mohd Zaini ASMAWI; Shaida Fariza SULAIMAN; Othman Ahmad SOFIMAN

    2011-01-01

    In this study,freeze-dried water extract from the leaves of Myristica fragrans (Houtt.) was tested for mutagenic and antimutagenic potentials using the Allium cepa assay.Freeze-dried water extract alone and its combination with cyclophosphamide (CP) (50 mg/kg) were separately dissolved in tap water at 500,1000,2000,and 4000 mg/kg.Onions (A.cepa) were suspended in the solutions and controls for 48 h in the dark.Root tips were prepared for microscopic evaluation.2,2-Diphenyl-1-picrylhydrazyl (DPPH) free radicals' scavenging power of the extract was tested using butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) as standards.Water extract of Myristica fragrans scavenged free radicals better than BHA,but worse than BHT.The extract alone,as well as in combination with CP suppressed cell division,and induced chromosomal aberrations that were insignificantly different from the negative control (P≤0.05).However,cytotoxic and mutagenic actions of CP were considerably suppressed.The observed effects on cell division and chromosomes of A.cepa may be principally connected to the antioxidant properties of the extract.The obtained results suggest mitodepressive and antimutagenic potentials of water extract of the leaves of M.fragrans as desirable properties of a promising anticancer agent.

  2. Phenolic extracts of coconut oil cake: a potential alternative for synthetic antioxidants

    Directory of Open Access Journals (Sweden)

    Kapila Nalawatta SENEVIRATNE

    2016-01-01

    Full Text Available Abstract Limitations of natural antioxidants include relatively low antioxidant activity, narrow range of food systems where the antioxidants are effective and limited thermal stability compared to synthetic antioxidants. In the present study, the phenolic extract of coconut oil cake (COCE was tested for antioxidant activity-related food stabilization. Heat stabilities of COCE and synthetic antioxidants were determined by measuring the indubbction time of sunflower oil enriched with heat-treated antioxidants. In the β-carotene-linoleate emulsion used for testing antioxidant activity, COCE can retain 96 ± 2% of initial colour intensity while BHT can retain 89 ± 2% of initial colour intensity at 60 µg mL–1 concentration after two hours. TBARS contents (MDA equivalents / kg of meat in COCE-treated and control pork samples after 14 days was 2.80 ± 0.57 and 22.55 ± 2.30 respectively. Heat stability varies in the order butylated hydroxytoluene (BHT < (butylated hydroxyanisole (BHA < COCE < tertiary butylhydroxyquinone (TBHQ. The results of these experiments suggest that COCE is a versatile and thermally stable natural antioxidant mixture effective in stabilizing many food systems.

  3. Effect of EMA and antioxidants on properties of thermoplastic starch blown films

    Science.gov (United States)

    Threepopnatkul, P.; Kulsetthanchalee, C.; Sittattrakul, A.; Kaewjinda, E.

    2015-07-01

    The objectives of this study were to investigate the effect of poly(ethylene-co-methyl acrylate) (EMA) at 10, 30 and 50 wt% on the morphological properties, moisture sorption, water vapor permeability and biodegradability of thermoplastic starch (TPS). Urea and formamide were used as a mixed plasticizer. In addition, the effect of antioxidants namely, 3,5-di-tert-butyl-4-hydroxyhydrocinnamate (DTBH), butylated hydroxytoluene (BHT) and bis(octadecyl)hydroxylamine (BOH) at 1 wt% on the properties of TPS/EMA film was investigated. TPS/EMA films were produced by a blown film molding machine and characterized by scanning electron microscropy, moisture sorption, water vapor permeability and biodegradability measurement. Results found that the increment of EMA content in the TPS matrix could improve the water sorption, water vapor permeability and biodegradability properties of TPS/EMA films. For biodegradation, the weight loss of the blended films was directly proportional to TPS content. Regarding the antioxidants effect, the water vapor permeability of TPS/EMA films containing DTBH was higher than the one with BOH and BHT. However, the antioxidants contributed little to the biodegradability of TPS/EMA films and had no effect on the moisture sorption of TPS/EMA films.

  4. Spectroscopic studies on the antioxidant activity of ellagic acid

    Science.gov (United States)

    Kilic, Ismail; Yeşiloğlu, Yeşim; Bayrak, Yüksel

    2014-09-01

    Ellagic acid (EA, C14H6O8) is a natural dietary polyphenol whose benefits in a variety of diseases shown in epidemiological and experimental studies involve anti-inflammation, anti-proliferation, anti-angiogenesis, anticarcinogenesis and anti-oxidation properties. In vitro radical scavenging and antioxidant capacity of EA were clarified using different analytical methodologies such as total antioxidant activity determination by ferric thiocyanate, hydrogen peroxide scavenging, 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH) scavenging, 2,2‧-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activity and superoxide anion radical scavenging, ferrous ions (Fe2+) chelating activity and ferric ions (Fe3+) reducing ability. EA inhibited 71.2% lipid peroxidation of a linoleic acid emulsion at 45 μg/mL concentration. On the other hand, butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA), α-tocopherol and ascorbic acid displayed 69.8%, 66.8%, 64.5% and 59.7% inhibition on the peroxidation of linoleic acid emulsion at the same concentration, respectively. In addition, EA had an effective DPPH• scavenging, ABTSrad + scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, ferric ions (Fe3+) reducing power and ferrous ions (Fe2+) chelating activities. Also, those various antioxidant activities were compared to BHA, BHT, α-tocopherol and ascorbic acid as references antioxidant compounds. These results suggested that EA can be used in the pharmacological, food industry and medicine because of these properties.

  5. Spectroscopic studies on the antioxidant activity of p-coumaric acid

    Science.gov (United States)

    Kiliç, Ismail; Yeşiloğlu, Yeşim

    2013-11-01

    p-coumaric acid (4-hydroxycinnamic acid), a phenolic acid, is a hydroxyl derivative of cinnamic acid. It decreases low density lipoprotein (LDL) peroxidation and reduces the risk of stomach cancer. In vitro radical scavenging and antioxidant capacity of p-coumaric acid were clarified using different analytical methodologies such as total antioxidant activity determination by ferric thiocyanate, hydrogen peroxide scavenging, 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH) scavenging, 2,2‧-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging activity and superoxide anion radical scavenging, ferrous ions (Fe2+) chelating activity and ferric ions (Fe3+) reducing ability. p-Coumaric acid inhibited 71.2% lipid peroxidation of a linoleic acid emulsion at 45 μg/mL concentration. On the other hand, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), α-tocopherol and ascorbic acid displayed 66.8%, 69.8%, 64.5% and 59.7% inhibition on the peroxidation of linoleic acid emulsion at the same concentration, respectively. In addition, p-coumaric acid had an effective DPPHrad scavenging, ABTSrad + scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, ferric ions (Fe3+) reducing power and ferrous ions (Fe2+) chelating activities. Also, those various antioxidant activities were compared to BHA, BHT, α-tocopherol and ascorbic acid as references antioxidant compounds. These results suggested that p-coumaric acid can be used in the pharmacological and food industry because of these properties.

  6. Theoretical calculations of hyperfine coupling constants for muoniated butyl radicals.

    Science.gov (United States)

    Chen, Ya Kun; Fleming, Donald G; Wang, Yan Alexander

    2011-04-01

    The hyperfine coupling constants (HFCCs) of all the butyl radicals that can be produced by muonium (Mu) addition to butene isomers (1- and 2-butene and isobutene) have been calculated, to compare with the experimental results for the muon and proton HFFCs for these radicals reported in paper II (Fleming, D. G.; et al. J. Phys. Chem. A 2011, 10.1021/jp109676b) that follows. The equilibrium geometries and HFCCs of these muoniated butyl radicals as well as their unsubstituted isotopomers were treated at both the spin-unrestricted MP2/EPR-III and B3LYP/EPR-III levels of theory. Comparisons with calculations carried out for the EPR-II basis set have also been made. All calculations were carried out in vacuo at 0 K only. A C-Mu bond elongation scheme that lengthens the equilibrium C-H bond by a factor of 1.076, on the basis of recent quantum calculations of the muon HFCCs of the ethyl radical, has been exploited to determine the vibrationally corrected muon HFCCs. The sensitivity of the results to small variations around this scale factor was also investigated. The computational methodology employed was "benchmarked" in comparisons with the ethyl radical, both with higher level calculations and with experiment. For the β-HFCCs of interest, compared to B3LYP, the MP2 calculations agree better with higher level theories and with experiment in the case of the eclipsed C-Mu bond and are generally deemed to be more reliable in predicting the equilibrium conformations and muon HFCCs near 0 K, in the absence of environmental effects. In some cases though, the experimental results in paper II demonstrate that environmental effects enhance the muon HFCC in the solid phase, where much better agreement with the experimental muon HFCCs near 0 K is found from B3LYP than from MP2. This seemingly better level of agreement is probably fortuitous, due to error cancellations in the DFT calculations, which appear to mimic these environmental effects. For the staggered proton HFCCs of the

  7. Free radical scavenging abilities of flavonoids as mechanism of protection against mutagenicity induced by tert-butyl hydroperoxide or cumene hydroperoxide in Salmonella typhimurium TA102.

    Science.gov (United States)

    Edenharder, R; Grünhage, D

    2003-09-09

    Mutagenicity induced by tert-butyl hydroperoxide (BHP) or cumene hydroperoxide (CHP) in Salmonella typhimurium TA102 was effectively reduced by flavonols with 3',4'-hydroxyl groups such as fisetin, quercetin, rutin, isoquercitrin, hyperoxide, myricetin, myricitrin, robinetin, and to a lesser extent also by morin and kaempferol (ID50=0.25-1.05 micromol per plate). With the exception of isorhamnetin, rhamnetin, morin, and kaempferol, closely similar results were obtained with both peroxides. Hydrogenation of the double bond between carbons 2 and 3 (dihydroquercetin, dihydrorobinetin) as well as the additional elimination of the carbonyl function at carbon 4 (catechins) resulted in a loss of antimutagenicity with the notable exception of catechin itself. Again, all flavones and flavanones tested were inactive except luteolin, luteolin-7-glucoside, diosmetin, and naringenin. The typical radical scavenger butylated hydroxytoluene also showed strong antimutagenicity against CHP (ID50=5.4 micromol per plate) and BHP (ID50=11.4 micromol per plate). Other lipophilic scavengers such as alpha-tocopherol and N,N'-diphenyl-1,4-phenylenediamine exerted only moderate effects, the hydrophilic scavenger trolox was inactive. The metal chelating agent 1,10-phenanthroline strongly reduced mutagenicities induced by CHP and BHP (ID50=2.75 and 2.5 micromol per plate) at low concentrations but induced mutagenic activities at higher concentrations. The iron chelator deferoxamine mesylate, however, was less effective in both respects. The copper chelator neocuproine effectively inhibited mutagenicity induced by BHP (ID50=39.7 micromol per plate) and CHP (ID50=25.9 micrommol per plate), the iron chelator 2,2'-dipyridyl was less potent (ID50=6.25 mmol per plate against BHP, 0.42 mmol per plate against CHP). In the absence of BHP and CHP, yet not in the presence of these hydroperoxides, quercetin, rutin, catechin, epicatechin, and naringenin induced strong mutagenic activities in S

  8. Interactions between water and 1-butyl-1-methylpyrrolidinium ionic liquids

    Energy Technology Data Exchange (ETDEWEB)

    Fadeeva, Tatiana A.; DeVine, Jessalyn A.; Castner, Edward W., E-mail: ed.castner@rutgers.edu [Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854 (United States); Husson, Pascale [CNRS, UMR 6296, Institut de Chimie de Clermont-Ferrand, BP 80026, F-63171 Aubière (France); Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, BP 10448, F-63000 Clermont-Ferrand (France); Costa Gomes, Margarida F. [CNRS, UMR 6296, Institut de Chimie de Clermont-Ferrand, BP 80026, F-63171 Aubière (France); Greenbaum, Steven G. [Department of Physics and Astronomy, Hunter College, CUNY, New York, New York 10065 (United States)

    2015-08-14

    We report experimental results on the diffusivity of water in two ionic liquids obtained using the pulsed-gradient spin-echo NMR method. Both ionic liquids have the same cation, 1-butyl-1-methylpyrrolidinium, but different trifluoromethyl-containing anions. One has a strongly hydrophobic anion, bis(trifluoromethylsulfonyl)amide, while the second has a hydrophilic anion, trifluoromethylsulfonate. Transport of water in these ionic liquids is much faster than would be predicted from hydrodynamic laws, indicating that the neutral water molecules experience a very different friction than the anions and cations at the molecular level. Temperature-dependent viscosities, conductivities, and densities are reported as a function of water concentration to further analyze the properties of the ionic liquid-water mixtures. These results on the properties of water in ionic liquids should be of interest to researchers in diverse areas ranging from separations, solubilizing biomass and energy technologies.

  9. Interactions between water and 1-butyl-1-methylpyrrolidinium ionic liquids.

    Science.gov (United States)

    Fadeeva, Tatiana A; Husson, Pascale; DeVine, Jessalyn A; Costa Gomes, Margarida F; Greenbaum, Steven G; Castner, Edward W

    2015-08-14

    We report experimental results on the diffusivity of water in two ionic liquids obtained using the pulsed-gradient spin-echo NMR method. Both ionic liquids have the same cation, 1-butyl-1-methylpyrrolidinium, but different trifluoromethyl-containing anions. One has a strongly hydrophobic anion, bis(trifluoromethylsulfonyl)amide, while the second has a hydrophilic anion, trifluoromethylsulfonate. Transport of water in these ionic liquids is much faster than would be predicted from hydrodynamic laws, indicating that the neutral water molecules experience a very different friction than the anions and cations at the molecular level. Temperature-dependent viscosities, conductivities, and densities are reported as a function of water concentration to further analyze the properties of the ionic liquid-water mixtures. These results on the properties of water in ionic liquids should be of interest to researchers in diverse areas ranging from separations, solubilizing biomass and energy technologies.

  10. Picosecond photoexcitation dynamics in poly(3-butyl-thiophene) films

    Science.gov (United States)

    Frolov, S. V.; Wei, X.; Gellermann, W.; Vardeny, Z. V.; Ehrenfreund, E.

    1998-02-01

    We have studied photoexcitation dynamics in thin films of poly(3-butyl-thiophene) [P3BT] using ps transient and cw photomodulation techniques, streak camera imaging, electroabsorption and optically detected magnetic resonance spectroscopies. We have determined that intrachain excitons are the primary photoexcitations with a characteristic transient photomodulation spectrum consisting of two photoinduced absorption bands in the near IR spectral range and a broad stimulated emission band in the visible spectral region. The photogenerated excitons are relatively short-lived (150 ps) and can subsequently decay into polaron pairs and triplets, which are longer-lived excitations with lifetimes of order ms. We do not find stimulated emission in very thin P3BT films and this is attributed to high defect concentration close to the film surface.

  11. Modeling Low Density Polyethylene with Precisely Placed Butyl Branches

    Science.gov (United States)

    Rojas, Giovanni; Wagener, Kenneth B.

    Polyethylene (PE) is a commodity produced on a massive scale and also is one of the most studied macromolecules. Crystallinity can be controlled by copolymerizing ethylene with α-olefins, producing a wide range of material responses. Physical properties of PE, obtained via α olefin copolymerization, depend on the branch content that is directly related to the comonomer incorporation into the PE backbone. Materials with unknown primary structures are produced via chaingrowth chemistry, because unwanted side reactions generate defects in the main backbone that alter the morphological behavior and thermal response. Acyclic diene metathesis (ADMET) polymerization/hydrogenation methodology produce perfect sequenced copolymers of ethylene with α-olefins. Synthesis and thermal properties of PE with butyl branches precisely placed along the polymer backbone using ADMET chemistry is described within.

  12. tert-Butyl 2-methyl-2-(4-methylbenzoylpropanoate

    Directory of Open Access Journals (Sweden)

    Graham B. Gould

    2010-02-01

    Full Text Available The title compound, C16H22O3, is bent with a dihedral angle of 75.3 (1° between the mean planes of the benzene ring and a group encompassing the ester functionality (O=C—O—C. In the crystal, the molecules are linked into infinite chains held together by weak C—H...O hydrogen-bonded interactions between an H atom on the benzene ring of one molecule and an O atom on the ketone functionality of an adjacent molecule. The chains are arranged with neighbouring tert-butyl and dimethyl groups on adjacent chains exhibiting hydrophobic stacking, with short C—H...H—C contacts (2.37 Å between adjacent chains

  13. Synthesis and reinforcement of peroxide-cured butyl rubber thermosets

    Science.gov (United States)

    Rodrigo, Antonio Cillero

    Isobutylene-rich elastomers provide the oxidative stability and impermeability required by many industrial applications. Halogenated derivatives support a wide range of chemical modification processes that can overcome most performance limitations. This research involves the modification of brominated butyl rubber (BIIR) to introduce peroxide-curable functionality in addition to aminotrialkoxysilyl groups that improve interactions with siliceous fillers, and anthraquinone functionality that serves as a polymer-bound chromophore. The thesis also describes detailed studies of the influence of counter anions on imidazolium ionomer derivatives of brominated poly(isobutylene-co-p-methylstyrene) (BIMS). Exchanging bromide with dodecyl sulfate, styrene sulfonate and montmorillonite clay platelets provided new ionomer thermosets whose rheological, tensile and adhesive properties varied considerably from their parent material.

  14. Hydrolysis of tert-butyl formate: Kinetics, products, and implications for the environmental impact of methyl tert-butyl ether

    Science.gov (United States)

    Church, Clinton D.; Pankow, James F.; Tratnyek, Paul G.

    1999-01-01

    Asessing the environmental fate of methyl tert-butyl ether (MTBE) has become a subject of renewed interest because of the large quantities of this compound that are being used as an oxygenated additive in gasoline. Various studies on the fate of MTBE have shown that it can be degraded to tert-butyl formate (TBF), particularly in the atmosphere. Although it is generally recognized that TBF is subject to hydrolysis, the kinetics and products of this reaction under environmentally relevant conditions have not been described previously. In this study, we determined the kinetics of TBF hydrolysis as a function of pH and temperature. Over the pH range of 5 to 7, the neutral hydrolysis pathway predominates, with kN = (1.0 ± 0.2) × 10−6/s. Outside this range, strong pH effects were observed because of acidic and basic hydrolyses, from which we determined that kA = (2.7 ± 0.5) × 10−3/(M·s) and kB = 1.7 ± 0.3/(M·s). Buffered and unbuffered systems gave the same hydrolysis rates for a given pH, indicating that buffer catalysis was not significant under the conditions tested. The activation energies corresponding to kN, kA, and kBwere determined to be 78 ± 5, 59 ± 4, and 88 ±11 kJ/mol, respectively. In all experiments, tert-butyl alcohol was found at concentrations corresponding to stoichiometric formation from TBF. Based on our kinetics data, the expected half-life for hydrolysis of TBF at pH = 2 and 4°C (as per some standard preservation protocols for water sampling) is 6 h. At neutral pH and 22°C, the estimated half-life is 5 d, and at pH = 11 and 22°C, the value is only 8 min.

  15. Gamma-radiation effect on thermal ageing of butyl rubber compounds

    Energy Technology Data Exchange (ETDEWEB)

    Scagliusi, Sandra R.; Cardoso, Elizabeth C.L.; Lugao, Ademar B., E-mail: srscagliusi@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2015-07-01

    Butyl rubber has a comprehensive use in sealing systems, especially in tires inner tubes, due to their low permeability to gases. So, it is required that butyl rubber compounds show a better performance, more and more. Butyl rubber is provided with excellent mechanical properties and oxidation resistance. Besides showing these properties, radiation exposures impart modifications in physical-chemical and morphological properties on butyl rubber materials. When exposed to gamma-radiation, rubbers suffer changes in their mechanical and physical properties, caused by material degradation. The major radiation effect in butyl rubbers is chain scission; besides, ageing promotes too the same effect with further build-up of free radicals. This work aims to the study of gamma-radiation in physical-chemical properties of butyl rubber subjected to thermal ageing. Doses used herein were: 25 kGy, 50 kGy, 100 kGy, 150 kGy and 200 KGy. Samples were evaluated before and after ageing according to traditional essays, such as: hardness, tensile strength and elongation at break. From accomplished assessments it is possible to affirm that at doses higher than 50 kGy it was observed a sharp decreasing in butyl rubber physical-chemical properties, before and after exposure to ageing. (author)

  16. Thyroid disruption by Di-n-butyl phthalate (DBP and mono-n-butyl phthalate (MBP in Xenopus laevis.

    Directory of Open Access Journals (Sweden)

    Ouxi Shen

    Full Text Available BACKGROUND: Di-n-butyl phthalate (DBP, a chemical widely used in many consumer products, is estrogenic and capable of producing seriously reproductive and developmental effects in laboratory animals. However, recent in vitro studies have shown that DBP and mono-n-butyl phthalate (MBP, the major metabolite of DBP, possessed thyroid hormone receptor (TR antagonist activity. It is therefore important to consider DBP and MBP that may interfere with thyroid hormone system. METHODOLOGY/PRINCIPAL FINDINGS: Nieuwkoop and Faber stage 51 Xenopus laevis were exposed to DBP and MBP (2, 10 or 15 mg/L separately for 21 days. The two test chemicals decelerated spontaneous metamorphosis in X. laevis at concentrations of 10 and 15 mg/L. Moreover, MBP seemed to possess stronger activity. The effects of DBP and MBP on inducing changes of expression of selected thyroid hormone response genes: thyroid hormone receptor-beta (TRβ, retinoid X receptor gamma (RXRγ, alpha and beta subunits of thyroid-stimulating hormone (TSHα and TSHβ were detected by qPCR at all concentrations of the compounds. Using mammalian two-hybrid assay in vitro, we found that DBP and MBP enhanced the interactions between co-repressor SMRT (silencing mediator for retinoid and thyroid hormone receptors and TR in a dose-dependent manner, and MBP displayed more markedly. In addition, MBP at low concentrations (2 and 10 mg/L caused aberrant methylation of TRβ in head tissue. CONCLUSIONS: The current findings highlight potential disruption of thyroid signalling by DBP and MBP and provide data for human risk assessment.

  17. Ethyl tertiary-butyl ether: a toxicological review.

    Science.gov (United States)

    McGregor, Douglas

    2007-05-01

    A number of oxygenated compounds (oxygenates) are available for use in gasoline to reduce vehicle exhaust emissions, reduce the aromatic compound content, and avoid the use of organo-lead compounds, while maintaining high octane numbers. Ethyl tertiary-butyl ether (ETBE) is one such compound. The current use of ETBE in gasoline or petrol is modest but increasing, with consequently similar trends in the potential for human exposure. Inhalation is the most likely mode of exposure, with about 30% of inhaled ETBE being retained by the lungs and distributed around the body. Following cessation of exposure, the blood concentration of ETBE falls rapidly, largely as a result of its metabolism to tertiary-butyl alcohol (TBA) and acetaldehyde. TBA may be further metabolized, first to 2-methyl-1,2-propanediol and then to 2-hydroxyisobutyrate, the two dominant metabolites found in urine of volunteers and rats. The rapid oxidation of acetaldehyde suggests that its blood concentration is unlikely to rise above normal as a result of human exposure to sources of ETBE. Single-dose toxicity tests show that ETBE has low toxicity and is essentially nonirritant to eyes and skin; it did not cause sensitization in a maximization test in guinea pigs. Neurological effects have been observed only at very high exposure concentrations. There is evidence for an effect of ETBE on the kidney of rats. Increases in kidney weight were seen in both sexes, but protein droplet accumulation (with alpha(2u)-globulin involvement) and sustained increases in cell proliferation occurred only in males. In liver, centrilobular necrosis was induced in mice, but not rats, after exposure by inhalation, although this lesion was reported in some rats exposed to very high oral doses of ETBE. The proportion of liver cells engaged in S-phase DNA synthesis was increased in mice of both sexes exposed by inhalation. ETBE has no specific effects on reproduction, development, or genetic material. Carcinogenicity studies

  18. n-Butyl Pyridinium Nitrate as a Reusable Ionic Liquid Medium for Knoevenagel Condensation

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The Knoevenagel condensation of carbonyl substrates with active methylene compounds proceeds smoothly with ammonium acetate as catalyst in n-butyl pyridinium nitrate to afford the desired products of good purity in moderate yields.

  19. Endoscopic Injection of a Ruptured Duodenal Varix with N-butyl-2-cyanoacrylate

    Directory of Open Access Journals (Sweden)

    Paulo Salgueiro

    2014-04-01

    Conclusions: The presented case supports endoscopic injection sclerotherapy with N-butyl-2-cyanoacrylate as a treatment option for ruptured duodenal varices that, despite being a rare event, when it occurs, is often fatal.

  20. The reclaiming of butyl rubber and in-situ compatibilization of thermoplastic elastomer by power ultrasound

    Science.gov (United States)

    Feng, Wenlai

    This is a study of the continuous ultrasound aided extrusion process for the in-situ compatibilization of isotactic polypropylene (iPP)/ethylene-propylene diene rubber (EPDM) thermoplastic elastomer (TPE) using a newly developed ultrasonic treatment reactor. The rheological, mechanical properties and morphology of the TPE with and without ultrasonic treatment were studied. In-situ compatibilization in the ultrasonically treated blends was observed as evident by their more stable morphology after annealing, improved mechanical properties and IR spectra. The obtained results indicated that ultrasonic treatment induced the thermo-mechanical degradations and led to the possibility of enhanced molecular transport and chemical reactions at the interfaces. Processing conditions were established for enhanced in situ compatibilization of the PP/EPDM TPE. The ultrasonic treatments of butyl rubber gum and ultrasonic devulcanization of butyl rubber, tire-curing bladder during extrusion using a grooved barrel ultrasonic reactor were carried out. The ultrasonic treatment of gum caused degradation of the polymer main chain leading to lower molecular weight, broader molecular weight distribution, less unsaturation and changes in physical properties. The devulcanization of butyl rubber was successfully accomplished only at severe conditions of ultrasonic treatment. The mechanical properties of vulcanizates prepared from devulcanized butyl rubber are comparable to that of the virgin vulcanizate. The molecular characterization of sol fraction of devulcanized butyl rubber showed the devulcanization and degradation of butyl rubber occurred simultaneously. 1H NMR transverse relaxation was also used to study butyl rubber gum before and after ultrasonic treatment, and ultrasonically devulcanized unfilled butyl rubber. The T2 relaxation decays were successfully described using a two-component model. The recyclability of tire-curing bladder was also investigated. Gel fraction, crosslink

  1. Etude de l'effet du gonflement par les solvants sur les proprietes du caoutchouc butyle

    Science.gov (United States)

    Nohile, Cedrick

    Polymers and in particular elastomers are widely used for personal protective equipment against chemical and biological hazards. Among them, butyl rubber is one of the most effective elastomers against chemicals. However, if this rubber has a very good resistance to a wide range of them, it is sensitive to non polar solvents. These solvents will easily swell the material and may dramatically affect its properties. This situation may involve a large risk for. butyl rubber protective equipment users. It is thus essential to improve the understanding of the effect of solvents on the properties of butyl rubber. The research that was carried out had two objectives: to identify the parameters controlling the resistance of butyl rubber to solvents and to study the effect of swelling on the properties of butyl rubber. The results show that the resistance of butyl rubber to solvents appears to be controlled by three main parameters: the chemical class of the solvent, its saturation vapor pressure and its molar volume. In addition, swelling affects butyl rubber mechanical properties in a permanent way. The effects can be attributed to the extraction of plasticizers by the solvent and to the degradation of the physico-chemical structure of the polymer network. This chemical degradation was linked to a phenomenon of differential swelling which seems to be controlled by the solvent flow inside the material. These results question some general beliefs within the field of protection against chemical risks. They also open new perspectives for the development of predictive tools relative to the behavior of butyl rubber in the presence of solvents

  2. APPLICATION OF PHOTOCATALYTIC PROCESS FOR REMOVAL OF METHYL TERT-BUTYL ETHER FROM HIGHLYCONTAMINATED WATER

    Directory of Open Access Journals (Sweden)

    A. Mesdaghinia

    2007-09-01

    Full Text Available The oxygenate methyl tert-butyl ether is added to gasoline to increase the octane level and to reduce carbon monoxide and hydrocarbon emissions by vehicles. The high mobility, water solubility, and resistance to natural attenuation associated with methyl tert-butyl ether may result in contamination of ground and surface waters. In this research the degradation of aqueous methyl tert-butyl ether at relatively high concentrations was investigated by UV-vis/TiO2/H2O2 photocatalytic process. The effect of important operational parameters such as pH, amount of H2O2, catalyst loading, and irradiation time were also studied. Concentrations of methyl tert-butyl ether and intermediates such as tert-butyl formate and tert-butyl alcohol were measured over a 180 min period using a gas chromatograph equipped with flame ionization detector and combined with headspace sampler. Results showed that the time required for complete degradation increased from 30 to 180min, when the initial concentration was increased from 10 to 500mg/L. The first order rate constant for degradation of methyl tert-butyl ether from the hydroxyl radical was estimated to be 0.177 to 0.022 1/min as the concentration increased from 10 to 500mg/L. Study on the overall mineralization monitored by total organic carbon (TOC analysis showed that in the initial concentration of 100mg/L methyl tert-butyl ether, complete mineralization was obtained after 110min under UV-vis/TiO2/H2O2 photocatalytic process.

  3. Biodegradation of methyl tert-butyl ether by Kocuria sp.

    Directory of Open Access Journals (Sweden)

    Kiković Dragan D.

    2012-01-01

    Full Text Available Methyl tert-butyl ether (MTBE has been used to replace the toxic compounds from gasoline and to reduce emission of air pollutants. Due to its intensive use, MTBE has become one of the most important environment pollutants. The aim of this paper is isolation and identification of the bacteria from wastewater sample of “HIP Petrohemija” Pančevo (Serbia, capable of MTBE biodegradation. The results of the investigation showed that only the bacterial isolate 27/1 was capable of growth on MTBE. The result of sequence analyzes of 16S rDNA showed that this bacterial isolate belongs to the Kocuria sp. After the incubation period of 86 days, the degradation rates of initial MTBE concentration of 25 and 125 μg/ml were 55 and 36%, respectively. These results indicated that bacteria Kocuria sp. is successfully adapted on MTBE and can be potentially used in bioremediation of soils and waters contaminated with MTBE.

  4. Dietary Exposure to Benzyl Butyl Phthalate in China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Lei; JIANG Ding Guo; SUI Hai Xia; WU Ping Gu; LIU Ai Dong; YANG Da Jin; LIU Zhao Ping; SONG Yan; LI Ning

    2016-01-01

    ObjectiveBenzyl butyl phthalate (BBP) is a plasticizer used in food contact materials. Dietary exposure to BBP might lead to reproduction and developmental damages to human. The present paper was aimed to assess the health risk of BBP dietary exposure in Chinese population. MethodsThe BBP contents were detected in 7409 food samples from 25 foodcategories by gas chromatography-mass spectrometry operated in selected ion monitoring (SIM) mode. The dietary exposures of BBP in different age and sex groups were estimated by combining the content data with food consumption data derived from 2002 China National Nutrient and Health Survey, and evaluated according to the tolerable daily intake (TDI) of BBP established by European Food safety Agency. ResultsIt was found that BBP was undetectable in most samples and the highest level was 1.69 mg/kg detected in a vegetable oil sample. The average dietary exposure of BBP in people aged≥2 years was 1.03 μg/kgbw perday and the highest average exposure was found in 2-6 years old children (1.98 μg/kg bw perday). The BBP exposure in 7-12 months old children excessed 10% of tolerable daily intake (TDI) in worst scenario. ConclusionThe health risk of BBP dietary exposure in Chinese population is low and, considering BBP alone, there is no safety concern.

  5. Embolotherapy using N-butyl cyanoacrylate for abdominal wall bleeding

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Young Ho; Koh, Young Hwan; Han, Dae Hee; Kim, Ji Hoon; Cha, Joo Hee; Lee, Eun Hye; Song, Chi Sung [Seoul National University Boramae Hospital, Seoul (Korea, Republic of)

    2008-05-15

    We describe our experience with the use of N-butyl cyanoacrylate (NBCA) embolization of abdominal wall bleeding and we evaluate the clinical effectiveness of the procedure. Embolization was performed in nine patients with abdominal wall bleeding. The sites of embolization were the left first lumbar (n = 1), left second lumbar (n = 1), right inferior epigastric (n 2), left inferior epigastric (n = 3), right circumflex iliac (n = 1), and left circumflex iliac artery (n = 1). A coil was used with NBCA in one patient due to difficulty in selecting only a bleeding focus and anticipated reflux. NBCA was mixed with Lipiodol at the ratio of 1:1 to 1:4. Blood pressure and heart rate were measured before and after the embolization procedure, and the serial hemoglobin and hematocrit levels and transfusion requirements were reviewed to evaluate hemostasis and rebleeding. Hemostasis was obtained in six out of the nine patients and technical success was achieved in all patients. There were no procedure-related complications. Four out of the nine patients died due to rebleeding of a subarachnoid hemorrhage (n = 1), multiorgan failure (n = 1), and hepatic failure (n =2) that occurred two to nine days after the embolization procedure. One patient had rebleeding. The five surviving patients had no rebleeding, and the patients continue to visit the clinical on an outpatient basis. NBCA embolization is a clinically safe procedure and is effective for abdominal wall bleeding.

  6. Degradation of n-butyl xanthate using fly ash as heterogeneous Fenton-like catalyst

    Institute of Scientific and Technical Information of China (English)

    陈绍华; 杜冬云

    2014-01-01

    Heterogeneous Fenton-like process using fly ash as a catalyst was studied to degrade n-butyl xanthate form aqueous solution. The different reaction parameters on the degradation efficiency of the process were investigated. The fly ash/H2O2 catalyst possesses a high oxidation activity for n-butyl xanthate degradation in aqueous solution. It is found that both the dosage of catalyst and initial solution pH significantly affect the n-butyl xanthate conversion efficient. The results indicate that by using 1.176 mmol/L H2O2 and 1.0 g/L fly ash catalyst with mass fraction of 4.14%Fe(III) oxide at pH 3.0, almost 96.90%n-butyl xanthate conversion and over 96.66%COD removal can be achieved within 120 min with heterogeneous catalysis by fly ash. CS2 as an intermediate of n-butyl xanthate oxidation. Finally, it is demonstrated that the fly ash/H2O2 catalytic oxidation process can be an efficient method for the treatment of n-butyl xanthate containing wastewater.

  7. N-butyl cyanoacrylate embolotherapy for acute gastroduodenal ulcer bleeding

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Young Ho; Kim, Ji Hoon; Koh, Young Hwan; Han, Dae Hee; Cha, Joo Hee; Seong, Chang Kyu; Song, Chi Sung [Seoul National University Boramae Hospital, Seoul (Korea, Republic of)

    2007-01-15

    Various embolic agents have been used for embolization of acute gastrointestinal (GI) arterial bleeding. N-butyl cyanoacrylate (NBCA) is not easy to handle, but it is a useful embolic agent. In this retrospective study, we describe our experience with NBCA embolization of acute gastroduodenal ulcer bleeding. NBCA embolization was performed in seven patients with acute upper GI arterial bleeding; they had five gastric ulcers and two duodenal ulcers. NBCA embolization was done in the left gastric artery (n = 3), right gastric artery (n = 2), gastroduodenal artery (n = 1) and pancreaticoduodenal artery (n = 1). Coil was used along with NBCA in a gastric bleeding patient because of difficulty in selecting a feeding artery. NBCA was mixed with Lipiodol at the ratio of 1:1 to 1:2. The blood pressure and heart rate around the time of embolization, the serial hemoglobin and hematocrit levels and the transfusion requirements were reviewed to evaluate hemostasis and rebleeding. Technical success was achieved in all the cases. Two procedure-related complications happened; embolism of the NBCA mixture to the common hepatic artery occurred in a case with embolization of the left gastric artery, and reflux of the NBCA mixture occurred into the adjacent gastric tissue, but these did not cause any clinical problems. Four of seven patients did not present with rebleeding, but two had rebleeding 10 and 16 days, respectively, after embolization and they died of cardiac arrest at 2 months and 37 days, respectively. One other patient died of sepsis and respiratory failure within 24 hours without rebleeding. NBCA embolization with or without other embolic agents could be safe and effective for treating acute gastroduodenal ulcer bleeding.

  8. Transcatheter Embolotherapy with N-Butyl Cyanoacrylate for Ectopic Varices

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jin Woo; Kim, Hyo-Cheol, E-mail: angiointervention@gmail.com; Jae, Hwan Jun, E-mail: jaemdphd@gmail.com; Jung, Hyun-Seok; Hur, Saebeom; Lee, Myungsu; Chung, Jin Wook [Seoul National University Hospital, Department of Radiology, Seoul National University College of Medicine (Korea, Republic of)

    2015-04-15

    PurposeTo address technical feasibility and clinical outcome of transcatheter embolotherapy with N-butyl cyanoacrylate (NBCA) for bleeding ectopic varices.MethodsThe institutional review board approved this retrospective study and waived informed consent. From January 2004 to June 2013, a total of 12 consecutive patients received transcatheter embolotherapy using NBCA for bleeding ectopic varices in our institute. Clinical and radiologic features of the endovascular procedures were comprehensively reviewed.ResultsPreprocedural computed tomography images revealed ectopic varices in the jejunum (n = 7), stoma (n = 2), rectum (n = 2), and duodenum (n = 1). The 12 procedures consisted of solitary embolotherapy (n = 8) and embolotherapy with portal decompression (main portal vein stenting in 3, transjugular intrahepatic portosystemic shunt in 1). With regard to vascular access, percutaneous transhepatic access (n = 7), transsplenic access (n = 4), and transjugular intrahepatic portosystemic shunt tract (n = 1) were used. There was no failure in either the embolotherapy or the vascular accesses (technical success rate, 100 %). Two patients died within 1 month from the procedure from preexisting fatal medical conditions. Only one patient, with a large varix that had been partially embolized by using coils and NBCA, underwent rebleeding 5.5 months after the procedure. The patient was retreated with NBCA and did not undergo any bleeding afterward for a follow-up period of 2.5 months. The remaining nine patients did not experience rebleeding during the follow-up periods (range 1.5–33.2 months).ConclusionTranscatheter embolotherapy using NBCA can be a useful option for bleeding ectopic varices.

  9. Chelation of heavy metals by potassium butyl dithiophosphate

    Institute of Scientific and Technical Information of China (English)

    Ying Xu; Zhigang Xie; Lu Xue

    2011-01-01

    Potassium butyl dithiophosphate (PBD) was developed and introduced as a new chelating agent for heavy metal removal.The synthesized PBD were characterized by IR and NMR.The effects of pH, chelating agent dosage, and other heavy metal ions on the performance of PBD in Cd2+ removal from water are investigated.Experimental results showed that the chelating agent could be used to treat acidic heavy metal wastewater.The Cd2+ removal was not affected by solution pH value within the range of 2 to 6.The Cd2+ removal rate could reach over 99%.Therefore, the deficiency of the precipitation process using hydroxide under alkaline condition can be overcome.Without the need for pH adjustment, the method could save on costs.If Cd2+ co-exists with Pb2+ and Cu2+, the affinity of the chelating agent with these three heavy metal ions was in the order of: Cu2+ > Pb2+ > Cd2+.Through PBD chelating precipitation,all the contents of Pb2+, Cd2+, and Cu2+ in wastewater met the standard levels through a one-step treatment.The one-step treatment process was superior to the process (sectional treatment is required) of precipitation with hydroxide.When the pH was between 3 and 11, the amount of leached chelated Cd2+ was much lower than that obtained by precipitation with hydroxide.Therefore, the risk of environmental pollution could be further reduced.

  10. The electrospinning of the copolymer of styrene and butyl acrylate for its application as oil absorbent.

    Science.gov (United States)

    Xu, Naiku; Cao, Jipeng; Lu, Yuyao

    2016-01-01

    Electrospun polystyrene materials have been employed as oil absorbents, but they have visible drawbacks such as poor strength at low temperature and unreliable integrity because of brittleness and insufficient cohesive force among fibers. Butyl acrylate can polymerize into flexible chains, and its polymer can be used as elastomer and adhesive material. Thereby it is possible to obtain the material that has better performance in comparison with electrospun polystyrene material through the electrospinning of the copolymer of styrene and butyl acrylate. In this work, a polymer was synthesized through suspension polymerization by using styrene and butyl acrylate as comonomers. The synthesis of the copolymer of styrene and butyl acrylate was verified through dissolution and hydrolysis experimental data; as well through nuclear magnetic resonance spectrometry. The viscous flow activation energy of the solution consisting of copolymer and N, N-dimethylformamide was determined via viscosity method and then adopted to establish the entanglement characteristics of butyl acrylate's chain segments. Finally, in order to electrospin the copolymer solution into fibrous membrane, the effects of monomer feed ratio and spinning parameters were investigated. The prepared fibrous membrane was found to have a potential use as oil absorbent.

  11. Alkylation of Catechol with tert-Butyl Alcohol Catalyzed by Mesoporous Acidic Montmorillonite Heterostructure Catalysts

    Institute of Scientific and Technical Information of China (English)

    周春晖; 葛忠华; 李小年; 童东绅; 李庆伟; 郭红强

    2004-01-01

    The liquid phase alkylation of catechol with tert-butyl alcohol to produce 4-tert-butyl catechol (4-TBC) was carried out over MCM-41, HZSM-5, H-exchanged montmorillonite and novel acidic porous montmorillonite heterostructures (PMHs). Upon all catalysts tested, 4-TBC is the main product and 3-tert-butyl catechol (3-TBC) and 3,5-di-tert-butyl catechol are the side products. The synthetic PMHs showed higher conversion of catechol and better selectivity to 4-TBC compared to other solid acid catalysts tested. Over the PMHs derived from H-exchanged montmorillonite through template extraction processes, the suitable reaction temperature is ca 410 K, the ratio of catechol to tert-butyl alcohol is 1:2. Increasing the amount of catalyst (lower weight hourly space velocity) can improve the conversion of catechol and influence the selectivity slightly. The reasonable reaction time is ca 8 h.The type and strength of acidity of H-montmorillonite and PMH were determined by pyridine adsorption FT-IR and ammonia temperature-programmed desorption techniques. The medium and strong acid sites are conducive to producing 4-TBC and the weak acid sites to facilitating the 3-TBC formation. The differences between the PMHs from calcination and those fi'om extraction are attributed to proton migration and acidity change in the gallery surface.

  12. Thermal decomposition mechanism of p-tert-butyl-calix[n]arenes

    Energy Technology Data Exchange (ETDEWEB)

    Chennakesavulu, K., E-mail: chennanml@yahoo.com [National Metallurgical Laboratory Madras Centre, CSIR Madras Complex, Taramani, Chennai 600 113 (India); Department of Chemistry, Sathyabama University, Jeppiaar Nagar, Chennai 600 119 (India); Sreedevi, P.; Raviathul Basaria, M. [National Metallurgical Laboratory Madras Centre, CSIR Madras Complex, Taramani, Chennai 600 113 (India); Ramanjaneya Reddy, G. [Department of Inorganic Chemistry, Guindy Campus, University of Madras, Chennai 600 025 (India); Sasipraba, T. [International Research Centre, Sathyabama University, Jeppiaar Nagar, Chennai 600 119 (India); Bhaskar Raju, G.; Prabhakar, S. [National Metallurgical Laboratory Madras Centre, CSIR Madras Complex, Taramani, Chennai 600 113 (India)

    2014-01-10

    Highlights: • Systematic thermal decomposition, structural elucidation of intermediates at various quenched temperatures. • At solid state the phenolic free radical was quenched and was evidenced by recording stable EPR. • Since the lower decomposition energy these p-tert-butyl-calix[n]arenes can be used as a antioxidants for thermal stabilization of polyolefins. • Solid state NMR CP-MAS studies show the breakage of calixarene at bridged methylene. • Kinetic triplets of p-tert-butyl-calixarenes were determined by model free methods. - Abstract: Thermal decomposition of p-tert-butyl-calix[n]arene was studied using thermo gravimetry (TG) and differential thermo gram (DTG) methods. Non-isothermal TG was done under static air atmosphere with 1, 2.5, 5.0 and 10.0 K/min. Model-free methods such as Friedman and Flynn Wall Ozawa (FWO) were used to evaluate the kinetic parameters such as activation energy and exponential factors. The probable thermal decomposition mechanism was proposed by analyzing the quenched intermediate p-tert-butyl-calix[n]arene samples with FTIR, mass, {sup 1}H NMR, {sup 13}C NMR cross polarization magic angle spectrometry (CP-MAS), EPR spectroscopy and elemental analysis. The thermal stability of the polyolefins was checked with p-tert-butyl-calix[n]arene as an antioxidant additive.

  13. Hydrogen bonded rings, chains and lassos: the case of t-butyl alcohol clusters

    Science.gov (United States)

    Zimmermann, D.; Häber, Th.; Schaal, H.; Suhm, M. A.

    Infrared OH stretching spectra of hydrogen bonded 2-methyl-propan-2-ol (t-butyl alcohol) clusters are investigated by ragout-jet FTIR spectroscopy. A spectral difference technique is used to discriminate approximately between neighbouring cluster sizes. Dimers, trimers and cyclic tetramers can be detected along with larger clusters, which exhibit a surprisingly structured vibrational fingerprint. Comparison is made to the spectra of related alcohols and to energetic and harmonic vibrational predictions from electronic structure calculations. The experimentally observed 32% increase in OH stretching wavenumber shift from methanol dimer to t-butyl alcohol dimer is reproduced at the HF/3-21G level (+ 33%). It is also qualitatively correct at the MP2/6-31+ G* level (+ 15%), whereas it has the wrong sign at the B3LYP/6-31+ G* level (-5%) and is negligible at the HF/6-31+ G* level, disregarding anharmonic effects. The cyclic tetramer of t-butyl alcohol is found to be particularly stable due to a favourable up-down alternation of the bulky t-butyl groups. Beyond the t-butyl alcohol tetramer, lasso structures are found to be energetically competitive with simple ring structures. A many-body decomposition shows that this is due to a reduced cooperativity in the sterically hindered pentamer ring. The resulting thermodynamic and kinetic relevance of cyclic tetramers is discussed.

  14. Human gallbladder morphology after gallstone dissolution with methyl tert-butyl ether.

    Science.gov (United States)

    vanSonnenberg, E; Zakko, S; Hofmann, A F; D'Agostino, H B; Jinich, H; Hoyt, D B; Miyai, K; Ramsby, G; Moossa, A R

    1991-06-01

    The effects of methyl tert-butyl ether exposure on the human gallbladder in five patients who were treated for gallstones by contact dissolution is described. Two patients underwent cholecystectomy within 1 week of methyl tert-butyl ether treatment, one patient 2 weeks after, another 10 weeks after, and one 12 weeks after. Indications for cholecystectomy were bilirubinate stones (resistant to methyl tert-butyl ether), catheter dislodgement, bile leakage, and gallstone recurrence (2 patients). Gallstones were dissolved completely in three patients, there was approximately 50% stone reduction in one patient, and no dissolution occurred in the fifth patient. Each gallbladder was examined grossly and histologically. Electron microscopic evaluation was performed in one cases. Typical inflammatory findings of chronic cholecystitis were observed in each gallbladder and were most conspicuous in the submucosa; the mucosal and serosal surfaces were intact. Mild acute inflammatory changes were noted in the submucosa in the two patients with the shortest interval between methyl tert-butyl ether administration and cholecystectomy. There were no ulcerations in the mucosa and no unusual wall thickening or fibrosis in any patient. These observations support the safety of methyl tert-butyl ether perfusion in the human gallbladder; the mild acute changes may be a transient and reversible phenomenon.

  15. Production of butyl-biodiesel using lipase physically-adsorbed onto electrospun polyacrylonitrile fibers.

    Science.gov (United States)

    Sakai, Shinji; Liu, Yuping; Yamaguchi, Tetsu; Watanabe, Rie; Kawabe, Masaaki; Kawakami, Koei

    2010-10-01

    Butyl-biodiesel production using electrospun polyacrylonitrile fibers with Pseudomonas cepacia lipase immobilized through physical adsorption was studied. About 80% conversion to butyl-biodiesel was achieved after 24h by suspending the catalyst at 2.4 mg/mL in a mixture of rapeseed oil and n-butanol at a molar ratio of 1:3, containing water at 8000 ppm at 40 degrees C. A further 24h of operation resulted in 94% conversion. The initial reaction rate detected for this process was 65-fold faster than those detected for Novozym 435 on a total catalyst mass basis. The immobilized lipase continued to work as a catalyst for 27 d, within a 15% reduction in conversion yield at the outlet of the reactor compared with the average value detected during the first 3d of operation in a continuous butyl-biodiesel production system.

  16. Spectroscopic analysis of 1-butyl-2,3-dimethylimidazolium ionic liquids: Cation-anion interactions

    Science.gov (United States)

    Men, Shuang; Jiang, Jing; Licence, Peter

    2017-04-01

    In this study, four 1-butyl-2,3-dimethylimidazolium ionic liquids are analysed by X-ray photoelectron spectroscopy, together with three 1-butyl-3-methylimidazolium ionic liquids. A reliable fitting model for the carbon 1s region of 1-butyl-2,3-dimethylimidazolium ionic liquids is modified according to established models. The effect of the anion on the electronic environment of the cation is explored based upon the comparison between measured binding energies of nitrogen 1s and the hydrogen bond acceptor ability. The effect of the cation on the cation-anion interaction is also demonstrated by carefully comparing the hydrogen bond donating ability of different cations, with a definite anion.

  17. Molecular recognition study of ethosuximide by the supramolecular probe, p-t-butyl calix(8)arene

    Energy Technology Data Exchange (ETDEWEB)

    Meenakshi, C., E-mail: geethu.laxi@gmail.com [Department of Chemistry, Shri Meenakshi Government College for Women (Autonomous), Madurai 625002 (India); Sangeetha, P.; Ramakrishnan, V. [Department of Laser Studies, School of Physics, Madurai Kamaraj University, Madurai 625021 (India)

    2013-06-15

    The supramolecule, p-t-Butyl calix(8)arene, forms inclusion complex with the antiseizure drug molecule, ethosuximide. This feature is explained on the basis of optical absorption spectroscopy. Here p-t-Butyl calix(8)arene is the host molecule and ethosuximide is the guest molecule. The stoichiometry of the host–guest complex and the binding constant has been determined using Benesi–Hildebrand plot. Based on the result obtained the structure of the inclusion complex has been proposed. -- Highlights: ► Third generation supramolecule, t-butyl calix (8) arene, is used as a host molecule. ► Anti seizure drug molecule is used as a guest molecule. ► Inclusion complex is formed between the host and guest molecule.

  18. The antioxidant behaviour of melatonin and structural analogues during lipid peroxidation depends not only on their functional groups but also on the assay system.

    Science.gov (United States)

    Fagali, Natalia; Catalá, Angel

    2012-07-13

    There is no general agreement yet on the antioxidant effect of pineal indoles against lipid peroxidation. Accordingly, the main goal of the present work was to study the antioxidant activity of melatonin (MLT), N-acetylserotonin (NAS), 5-HO-tryptophan (5HO-TRP) and 5-methoxytryptamine (5MTP) in two different lipid systems with high content of polyunsaturated fatty acids (PUFAs): triglycerides (rich in 20:5 n-3, 22:6 n-3) dissolved in chloroform and sonicated liposomes made of retinal lipids (rich in 22:6 n-3). In the triglyceride-chloroform-system the peroxidation reaction was initiated by cumene hydroperoxide (CHP) whereas liposomes were peroxidized with Fe(2+). The techniques employed at the present work were: (1) TBARS production, (2) DPPH assay, (3) determination of conjugated dienes production and (4) analysis of fatty acid profile by GC-MS. Butylated hydroxytoluene (BHT) was employed as a reference because of its well known antioxidant capacity. Our results showed that MLT and 5MTP were unable to protect PUFAs against lipid peroxidation in both systems, whereas NAS and 5HO-TRP were better antioxidants that BHT in the triglyceride-system but ineffective in the liposome-system. We conclude that the antioxidant behaviour of pineal indoles depends not only on their functional groups but also on the assay system and could be explained by the polar paradox theory.

  19. Antioxidant Capacity and Metal Content of Physalis Peruviana L. Fruit Sold in Markets

    Directory of Open Access Journals (Sweden)

    Ayse Eken

    2014-12-01

    Full Text Available Aim: The dietary intake of medicinal food with antioxidant activity and required amounts of trace elements is important to pursue good healthy life. In our study, we aimed to determine the antioxidant capacity and metal content of goldenberry (Physalis peruviana L. fruit sold in markets in Kayseri. Material and Method: The antioxidant capacity of P. peruviana fruit was determined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH free radical scavenging assay. The DPPH radical scavenger capacity of the methanol extract of fruit was compared with known antioxidants such as ascorbic acid, gallic acid, and butylated hydroxytoluene (BHT as references. The metal content of P. peruviana fruit was measured by using atomic absorption spectrometer (AAS. Results: The fruit of P. peruviana was found to possess DPPH free radical scavenging activity but the antioxidant capacity was lower than the standard substances. Inhibitory concentration 50% (IC50 values of P. peruviana, ascorbic acid, gallic acid, and BHT were determined as 32 mg/ml, 3.8 mg/ml, 3.51 mg/ml, and 1.21 mg/ml, respectively. As a result of the analysis by AAS, it was observed that P. peruviana fruit contented plentiful trace elements and the content of heavy metal was small amount or not detected. Discussion: These observations suggest that the fruit of P. peruviana has a potential source of antioxidant and trace elements of natural origin.

  20. Enzymatic synthesis of lipophilic rutin and vanillyl esters from fish byproducts.

    Science.gov (United States)

    Mbatia, Betty; Kaki, Shiva Shanker; Mattiasson, Bo; Mulaa, Francis; Adlercreutz, Patrick

    2011-07-13

    Lipase-catalyzed synthesis of lipophilic phenolic antioxidants was carried out with a concentrate of n-3 polyunsaturated fatty acids (PUFAs), recovered from oil extracted from salmon ( Salmon salar ) byproduct. Vanillyl alcohol and rutin were selected for the esterification reaction, and obtained esters yields were 60 and 30%, respectively. The antioxidant activities of the esters were compared with those of commercial butylated hydroxytoluene (BHT) and α-tocopherol using DPPH radical scavenging and thiobarbituric acid assays. In the DPPH assay, rutin esters showed better activity than vanillyl esters, and on the contrary in lipophilic medium, vanillyl esters were found to be superior to rutin esters. In bulk oil system, the antioxidant activities of rutin and vanillyl derivatives were lower than that of BHT and α-tocopherol, but in emulsion, they showed better activity than α-tocopherol. By attaching to natural phenolics, the PUFAs are protected against oxidation, and PUFA improves the hydrophobicity of the phenolic, which could enhance its function in lipid systems.

  1. Antioxidant effect of supercritical CO2 extracted Nigella sativa L. seed extract on deep fried oil quality parameters.

    Science.gov (United States)

    Solati, Zeinab; Baharin, Badlishah Sham

    2015-06-01

    Effect of supercritical CO2 extracted Nigella sativa L. seed extract (NE) on frying performance of sunflower oil and refined, bleached and deodorized (RBD) palm olein was investigated at concentrations of 1.2 % and 1.0 % respectively. Two frying systems containing 0 % N. sativa L. extract (Control) and 0.02 % butylated hydroxytoluene (BHT) were used for comparison. Physicochemical properties such as fatty acid composition (FAC), Peroxide Value (PV), Anisidine Value (AV), Totox Value (TV), Total Polar Content (TPC), C18:2/C16:0 ratio and viscosity of frying oils were determined during five consecutive days of frying. Results have shown that N. sativa L. extract was able to improve the oxidative stability of both frying oils during the frying process compared to control. The stabilizing effect of antioxidants were in the order of BHT > NE. RBD palm olein was found to be more stable than sunflower oil based on the ratio of linoleic acid (C18:2) to palmitic acid (C16:0) and fatty acid composition.

  2. 新疆药桑中稀有黄酮桑根酮M的分离鉴定及其抗氧化活性分析%Separation, Identification and Antioxidant Activity of Rare Flavonoid Sanggenon M in Black Mulberry Grown in Xinjiang

    Institute of Scientific and Technical Information of China (English)

    向伟; 喻艳; 刘静; 谷少伟; 徐立; 左少纯; 黄先智; 蒲彬

    2015-01-01

    经70%乙醇冷浸提取、不同溶剂萃取,在清除1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基活性跟踪下,通过多次柱层析及薄层层析(thin layer chromatography,TLC),从药桑枝条中分离得到一种稀有黄酮类化合物,经波谱鉴定、结构分析确定其为桑根酮M (sanggenon M).以人工合成的抗氧化剂二丁基羟基甲苯(butylated hydroxytoluene,BHT)为对照进行抗氧化活性实验,结果表明桑根酮M具有很好的抗氧化活性,其清除DPPH自由基和羟自由基(·OH)的IC50值分别为45.984 mg/L和65.692 mg/L(对照BHT的IC50值分别为64.189、231.556mg/L),总还原力也明显高于BHT.

  3. Use of time-of-flight mass spectrometry for large screening of organic pollutants in surface waters and soils from a rice production area in Colombia.

    Science.gov (United States)

    Hernández, F; Portolés, T; Ibáñez, M; Bustos-López, M C; Díaz, R; Botero-Coy, A M; Fuentes, C L; Peñuela, G

    2012-11-15

    The irrigate district of Usosaldaña, an important agricultural area in Colombia mainly devoted to rice crop production, is subjected to an intensive use of pesticides. Monitoring these compounds is necessary to know the impact of phytosanitary products in the different environmental compartments. In this work, surface water and soil samples from different sites of this area have been analyzed by applying an analytical methodology for large screening based on the use of time-of-flight mass spectrometry (TOF MS) hyphenated to liquid chromatography (LC) and gas chromatography (GC). Several pesticides were detected and unequivocally identified, such as the herbicides atrazine, diuron or clomazone. Some of their main metabolites and/or transformation products (TPs) like deethylatrazine (DEA), deisopropylatrazine (DIA) and 3,4-dichloroaniline were also identified in the samples. Among fungicides, carbendazim, azoxystrobin, propiconazole and epoxiconazole were the most frequently detected. Insecticides such as thiacloprid, or p,p'-DDT metabolites (p,p'-DDD and p,p'-DDE) were also found. Thanks to the accurate-mass full-spectrum acquisition in TOF MS it was feasible to widen the number of compounds to be investigated to other families of contaminants. This allowed the detection of emerging contaminants, such as the antioxidant 3,5-di-tertbutyl-4-hydroxy-toluene (BHT), its metabolite 3,5-di-tert-butyl-4-hydroxy-benzaldehyde (BHT-CHO), or the solar filter benzophenone, among others.

  4. The Role of Neutrophil Myeloperoxidase in Models of Lung Tumor Development

    Energy Technology Data Exchange (ETDEWEB)

    Rymaszewski, Amy L.; Tate, Everett; Yimbesalu, Joannes P. [Department of Pharmacology and Toxicology and MCW Cancer Center, Medical College of Wisconsin, Milwaukee, WI 53226 (United States); Gelman, Andrew E. [Department of Surgery, Washington University in St. Louis, St. Louis, MO 63130 (United States); Jarzembowski, Jason A. [Department of Pathology, Medical College of Wisconsin, Milwaukee, WI 53226 (United States); Zhang, Hao; Pritchard, Kirkwood A. Jr. [Department of Surgery and MCW Cancer Center, Medical College of Wisconsin, Milwaukee, WI 53226 (United States); Vikis, Haris G., E-mail: hvikis@mcw.edu [Department of Pharmacology and Toxicology and MCW Cancer Center, Medical College of Wisconsin, Milwaukee, WI 53226 (United States)

    2014-05-09

    Chronic inflammation plays a key tumor-promoting role in lung cancer. Our previous studies in mice demonstrated that neutrophils are critical mediators of tumor promotion in methylcholanthrene (MCA)-initiated, butylated hydroxytoluene (BHT)-promoted lung carcinogenesis. In the present study we investigated the role of neutrophil myeloperoxidase (MPO) activity in this inflammation promoted model. Increased levels of MPO protein and activity were present in the lungs of mice administered BHT. Treatment of mice with N-acetyl lysyltyrosylcysteine amide (KYC), a novel tripeptide inhibitor of MPO, during the inflammatory stage reduced tumor burden. In a separate tumor model, KYC treatment of a Lewis Lung Carcinoma (LLC) tumor graft in mice had no effect on tumor growth, however, mice genetically deficient in MPO had significantly reduced LLC tumor growth. Our observations suggest that MPO catalytic activity is critical during the early stages of tumor development. However, during the later stages of tumor progression, MPO expression independent of catalytic activity appears to be required. Our studies advocate for the use of MPO inhibitors in a lung cancer prevention setting.

  5. Pressurized liquid extraction-gas chromatography-mass spectrometry for confirming the photo-induced generation of dioxin-like derivatives and other cosmetic preservative photoproducts on artificial skin.

    Science.gov (United States)

    Alvarez-Rivera, Gerardo; Llompart, Maria; Garcia-Jares, Carmen; Lores, Marta

    2016-04-01

    The stability and photochemical transformations of cosmetic preservatives in topical applications exposed to UV-light is a serious but poorly understood problem. In this study, a high throughput extraction and selective method based on pressurized liquid extraction (PLE) coupled to gas chromatography-mass spectrometry (GC-MS) was validated and applied to investigate the photochemical transformation of the antioxidant butylated hydroxytoluene (BHT), as well as the antimicrobials triclosan (TCS) and phenyl benzoate (PhBz) in an artificial skin model. Two sets of photodegradation experiments were performed: (i) UV-Irradiation (8W, 254nm) of artificial skin directly spiked with the target preservatives, and (ii) UV-irradiation of artificial skin after the application of a cosmetic cream fortified with the target compounds. After irradiation, PLE was used to isolate the target preservatives and their transformation products. The follow-up of the photodegradation kinetics of the parent preservatives, the identification of the arising by-products, and the monitorization of their kinetic profiles was performed by GC-MS. The photochemical transformation of triclosan into 2,8-dichloro-dibenzo-p-dioxin (2,8-DCDD) and other dioxin-like photoproducts has been confirmed in this work. Furthermore, seven BHT photoproducts, and three benzophenones as PhBz by-products, have been also identified. These findings reveal the first evidences of cosmetic ingredients phototransformation into unwanted photoproducts on an artificial skin model.

  6. Extraction and in vitro antioxidant activity of exopolysaccharide by Pleurotus eryngii SI-02

    Directory of Open Access Journals (Sweden)

    Xinyi Sun

    2013-12-01

    Full Text Available The extraction parameters for Pleurotus eryngii SI-02 exopolysaccharide (EPS produced during submerged culture were optimized using response surface methodology (RSM. The optimum conditions for EPS extraction were predicted to be, precipitation time 20.24 h, ethanol concentration 89.62% and pH 8.17, and EPS production was estimated at 7.27 g/L. The actual yield of EPS under these conditions was 7.21 g/L. The in vitro antioxidant results of the EPS showed that the inhibition effects of EPS at a dosage of 400 mg/L on hydroxyl, superoxide anion and 1,1-diphenyl-2-picrylhydrazyl (DPPH radicals were 59.63 ± 3.72%, 38.69 ± 2.59%, and 66.36 ± 4.42%, respectively, which were 12.74 ± 1.03%, 8.01 ± 0.56%, and 12.19 ± 1.05% higher than that of butylated hydroxytoluene (BHT, respectively. The reducing power of EPS of P. eryngii SI-02 was 0.98 ± 0.05, 60.66 ± 5.14% higher than that of BHT. The results provide a reference for large-scale production of EPS by P. eryngii SI-02 in industrial fermentation and the EPS can be used as a potential antioxidant which enhances adaptive immune responses.

  7. Enhancing oxidative stability of sunflower oil during convective and microwave heating using grape seed extract.

    Science.gov (United States)

    Poiana, Mariana-Atena

    2012-01-01

    This study was performed to investigate the effectiveness of grape seed extract (GSE) compared to butylated hydroxytoluene (BHT) on retarding lipid oxidation of sunflower oil subjected to convection and microwave heating up to 240 min under simulated frying conditions. The progress of lipid oxidation was assessed in terms of peroxide value (PV), p-anisidine value (p-AV), conjugated dienes and trienes (CD, CT), inhibition of oil oxidation (IO) and TOTOX value. In addition, total phenolic content (TP) was evaluated in samples before and after heating in order to assess the changes in these compounds relative to the extent of lipid oxidation. The results of this study highlight that GSE showed a significantly inhibitory effect on lipid oxidation during both treatments, although to a different extent. This ability was dose-dependent; therefore, the extent of lipid oxidation was inversely related to GSE level. Convective heating, respective microwave exposure for 240 min of samples supplemented by GSE to a level of 1000 ppm, resulted in significant decreases of investigated indices relative to the control values as follows: PV (48%; 30%), p-AV (29%; 40%), CD (45%; 30%), CT (41%; 36%), TOTOX (35%; 37%). GSE to a level of 600-800 ppm inhibited the lipid oxidation in a similar manner to BHT. These results suggested that GSE can be used as a potential natural extract for improving oxidative stability of sunflower oil during thermal applications.

  8. Effect of dietary ethanol extracts of mango (Mangifera indica L.) on lipid oxidation and the color of chicken meat during frozen storage.

    Science.gov (United States)

    Freitas, Ednardo Rodrigues; da Silva Borges, Ângela; Pereira, Ana Lúcia Fernandes; Abreu, Virgínia Kelly Gonçalves; Trevisan, Maria Teresa Salles; Watanabe, Pedro Henrique

    2015-12-01

    The aim of this study was to evaluate the dietary effect of mango extracts on lipid stability and the coloring of broiler chicken breast meat during frozen storage. The treatments consisted of broiler chicken diet without antioxidants (control) and diets containing antioxidants: 200 ppm of butylated hydroxytoluene (BHT), 200 ppm of mango peel extract (MPE), 400 ppm of MPE, 200 ppm of mango seed extract (MSE), and 400 ppm of MSE. The broiler breasts were stored for 90 days and analysis of lipid oxidation and color was performed every 30 days. The thiobarbituric acid reactive substances values increased during storage and at 90 days, but the 400 ppm MSE treatment yielded lower values, indicating greater antioxidant activity. During storage, the lightness values decreased and the redness increased. Additions of 200 ppm BHT and 400 ppm MPE increased yellowness at 60 days of storage. Thus, mango peel and seed extracts added to broiler chicken diets reduce lipid oxidation and maintain color in breast meat during frozen storage, with mango seed extract at 400 ppm being the most effective.

  9. Caesalpinia decapetala Extracts as Inhibitors of Lipid Oxidation in Beef Patties

    Directory of Open Access Journals (Sweden)

    Maria G. Gallego

    2015-07-01

    Full Text Available In this study we investigated the effects of Caesalpinia decapetala (CD extracts on lipid oxidation in ground beef patties. Plant extracts and butylated hydroxytoluene (BHT were individually added to patties at both 0.1% and 0.5% (w/w concentrations. We assessed the antioxidant efficacy of CD by the ferric reducing antioxidant power (FRAP assay and evaluated their potential as natural antioxidants for meat preservation by thiobarbituric acid reactive substance (TBARS values, hexanal content, fatty acid composition and color parameters. These were tested periodically during 11 days of refrigerated storage. TBARS levels were significantly lower (p ≤ 0.05 in the samples containing plant extracts or BHT than in the non-treated control. In addition, the beef patties formulated with the selected plant extracts showed significantly (p ≤ 0.05 better color stability than those without antioxidants. These results indicate that edible plant extracts are promising sources of natural antioxidants and can potentially be used as functional preservatives in meat products.

  10. The antioxidant properties of dried extracts from the spent espresso coffee

    Directory of Open Access Journals (Sweden)

    Milutinović Milica D.

    2013-01-01

    Full Text Available The importance of coffee waste utilization is based on the fact that it contains a large amount of biologically valuable components. Preparation of espresso coffee produces substantial quantities of polyphenolic acids that have a significant antioxidant activity. In this work, the contents of polyphenols and antioxidant activity of extracts obtained from spent espresso coffee were analyzed using different solvent systems. The 70% solution of methanol, and 70% solution of ethanol and distilled water were used as solvents. The total amounts of polyphenols were determined by the Folin-Ciocalteu method, while the antioxidant activities were determined by DPPH inhibition (2,2-diphenyl-1-picrylhydrazyl and FRAP (Ferric Reducing Antioxidant Power. Both methods confirmed that the order of antioxidant activity of obtained dried extracts is as follows: water extract < methanol extract < ethanol extract, which was in accordance with their polyphenols content. Mild prooxidant activity was observed in the concentration of 200 μg/ml while investigating the DPPH inhibition. Prooxidant activity is a characteristic of some polypenolic acids that is considered to be one of the mechanisms of anticancer activity. The inhibition of DPPH radical, expressed by IC50 values, was compared with the results of the commercial antioxidants such are ascorbic acid and BHT (butylated hydroxytoluene. Comparing the IC50 values of ascorbic acid and BHT with the IC50 values of tested extracts it can be concluded that waste coffee extracts could be a good source of natural antioxidants.

  11. The 4-methylthio-1-butyl group for phosphate/thiophosphate protection in oligodeoxyribonucleotide synthesis.

    Science.gov (United States)

    Cieślak, Jacek; Grajkowski, Andrzej; Livengood, Victor; Beaucage, Serge L

    2004-12-01

    The detailed preparation of deoxyribonucleoside phosphoramidites functionalized with a 4-methylthio-1-butyl group for P(III) protection is described, along with the incorporation of these phosphoramidites into DNA oligonucleotides via solid-phase techniques. The versatility of the thermolabile 4-methylthio-1-butyl phosphate/thiophosphate-protecting group is exemplified through its facile removal from oligonucleotides under neutral conditions or under standard basic conditions. The sulfonium salt that is produced during the thermolytic deprotection of oligonucleotides did not alter DNA nucleobases or desulfurize phosphorothioate diesters to a significant extent.

  12. Percutaneous N-Butyl cyanoacrylate embolization of a pancreatic pseudoaneurysm after failed attempts of transcatheter embolization

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ri Hyeon; Yoo, Roh Eul; Kim, Hyo Cheol [Seoul National University Medical Research Center, and Clinical Research Institute, Seoul National University Hospital, Seoul (Korea, Republic of)

    2014-10-15

    One common complication after major pancreatic surgery is bleeding. Herein we describe a case of pancreatic pseudoaneurysm which developed after pylorous preserving pancreaticoduodenectomy for common bile duct cancer. Three attempts of transcatheter embolization failed since feeders to the pseudoaneurysm had unfavorable anatomy. Direct percutaneous N-butyl cyanoacrylate injection was performed under fluoroscopy-guidance and the pseudoaneurysm was successfully treated. Percutaneous fluoroscopy-guided direct N-butyl cyanoacrylate injection may be a useful alternative when selective transcatheter embolization fails or is technically challenging.

  13. Influence of Temperature on Thermodynamic Properties of Methyl t-Butyl Ether (MTBE) + Gasoline Additives

    Science.gov (United States)

    Gonzalez-Olmos, R.; Iglesias, M.; Goenaga, J. M.; Resa, J. M.

    2007-08-01

    The densities and sound speeds of binary mixtures of methyl tert-butyl ether (MTBE) + (benzene, toluene, ethylbenzene, isooctane, tert-butyl alcohol) have been measured at temperatures from 288.15 to 323.15 K and at atmospheric pressure over the complete concentration range. The experimental excess volumes and deviations of isentropic compressibility were calculated. The deviation of isentropic compressibility data have been analyzed in terms of different theoretical models; adequate agreement between the experimental and predicted values is obtained. The data from this study improve the data situation related to gasoline additives and help to understand the MTBE volumetric and acoustic behavior for various chemical systems.

  14. Pressure-induced phase transition of 1-butyl-3-methylimidazolium hexafluorophosphate [bmim][PF6

    Science.gov (United States)

    Takekiyo, Takahiro; Hatano, Naohiro; Imai, Yusuke; Abe, Hiroshi; Yoshimura, Yukihiro

    2011-03-01

    We have investigated the pressure-induced Raman spectral change of 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF6]) using Raman spectroscopy. The relative Raman intensity at 590 cm-1 of the CH2 rocking band assigned to the gauche conformer of the NCCC dihedral angle of the butyl group in the [bmim]+ cation increases when the pressure-induced liquid-crystalline phase transition occurs, while that at 610 cm-1 assigned to the trans conformer decreases. Our results show that the high-pressure phase transition of [bmim][PF6] causes the increase of the gauche conformer of the [bmim]+ cation.

  15. Estimation of the fraction of biologically active methyl tert-butyl ether degraders in a heterogeneous biomass sample

    DEFF Research Database (Denmark)

    Waul, Christopher Kevin; Arvin, Erik; Schmidt, Jens Ejbye

    2008-01-01

    The fraction of biologically active methyl tert-butyl ether degraders in reactors is just as important for prediction of removal rates as knowledge of the kinetic parameters. The fraction of biologically active methyl tert-butyl ether degraders in a heterogeneous biomass sample, taken from a packed...

  16. An alternative approach to synthesis of 2--butyl-5-nitrobenzofuran derivative: A key starting material for dronedarone hydrochloride

    Indian Academy of Sciences (India)

    P Raja Gopal; E R R Chandrashekar; M Saravanan; B Vijaya Bhaskar; P Veera Somaiah

    2012-09-01

    A practical synthesis of (2-butyl-5-nitrobenzofuran-3-yl)(4-hydroxyphenyl)methanone, a key intermediate in the preparation of anti arrhythmic drug, is described. The commercially available 4-nitrophenol (3) is converted in five steps to 2-butyl-5-nitrobenzofuran (9) which upon Friedel-Crafts acylation with 4-methoxybenzoyl chloride followed by deprotection of methyl group gives (2).

  17. Biodegradation of ethyl t-butyl ether (ETBE), methyl t-butyl ether (MTBE) and t-amyl methyl ether (TAME) by Gordonia terrae.

    Science.gov (United States)

    Hernandez-Perez, G; Fayolle, F; Vandecasteele, J P

    2001-01-01

    Gordonia terrae strain IFP 2001 was selected from activated sludge for its capacity to grow on ethyl t-butyl ether (ETBE) as sole carbon and energy source. ETBE was stoichiometrically degraded to t-butyl alcohol (TBA) and the activity was inducible. A constitutive strain, G. terrae IFP 2007, derived from strain IFP 2001, was also selected. Methyl t-butyl ether (MTBE) and t-amyl methyl ether (TAME) were not used as carbon and energy sources by the two strains, but cometabolic degradation of MTBE and TAME was demonstrated, to TBA and t-amyl alcohol (TAA) respectively, in the presence of a carbon source such as ethanol. No two-carbon compound was detected during growth on ETBE, but formate was produced during cometabolic degradation of MTBE or TAME. A monooxygenase was involved in the degradation of ethers, because no degradation of ETBE was observed under anaerobic conditions and the presence of a cytochrome P-450 was demonstrated in G. terrae IFP 2001 after induction by cultivation on ETBE.

  18. PHOTOCATALYTIC OXIDATION OF METHYL-TERT-BUTYL ETHER FOR DRINKING WATER TREATMENT

    Science.gov (United States)

    The photo-oxidation of methyl tert-butyl ether (MTBE) in water was investigated to determine the feasibility of using photocatalysis for the treatment of MTBE-contaminated drinking water. The feasibility assessment was conducted using slurries of titanium dioxide in both a photo-...

  19. A new efficient synthesis of isothiocyanates from amines using di-tert-butyl dicarbonate

    DEFF Research Database (Denmark)

    Munch, Henrik; Hansen, Jon S.; Pittelkow, Michael;

    2008-01-01

    Alkyl and aryl amines are converted smoothly to the corresponding isothiocyanates via the dithiocarbamates in good to excellent yields using di-tert-butyl dicarbonate (Boc(2)O) and 1-3 mol% of DMAP or DABCO as catalyst. As most of the byproducts are volatile, the work-up involves simple evaporation...

  20. (R-N-{2-tert-Butyl-2-[(R-tert-butylsulfonamido]ethylidene}-tert-butanesulfonamide

    Directory of Open Access Journals (Sweden)

    Cong-Bin Fan

    2008-10-01

    Full Text Available The title compound, C14H30N2O2S2, is the product of the monoaddition reaction of tert-butyl magnesium chloride with bis-[(R-N-tert-butanesulfinyl]ethanediimine. There are two almost identical molecules in the asymmetric unit, the molecular conformation of which is stabilized by an intramolecular N—H...N hydrogen bond.

  1. Optimization of coproduction of ethyl acetate and n-butyl acetate by reactive distillation☆

    Institute of Scientific and Technical Information of China (English)

    Hui Tian; Suying Zhao; Huidong Zheng; Zhixian Huang

    2015-01-01

    Based on a previous investigation, a simulation model was used for optimization of coproduction of ethyl acetate and n-butyl acetate by reactive distil ation. An experimental setup was established to verify the simulated results. The effects of various operating variables, such as ethanol feed location, acetic acid feed location, feed stage of reaction mixture of acetic acid and n-butanol, reflux ratio of ethyl acetate reactive distillation column, and distil-late to feed ratio of n-butyl acetate column, on the ethanol/n-butanol conversions, ethyl acetate/n-butyl acetate purity, and energy consumption were investigated. The optimal results in the simulation study are as follows:ethanol feed location, 15th stage;acetic acid feed location, eighth stage;feed location of reaction mixture of acetic acid and n-butanol, eighth stage;reflux ratio of ethyl acetate reactive distillation column, 2.0;and distillate to feed ratio of n-butyl acetate, 0.6.

  2. Energetic Materials Center Report--Small-Scale Safety and Thermal Testing Evaluation of Butyl Nitrate

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Peter C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Energetic Materials Center; Reynolds, John G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Energetic Materials Center

    2013-04-26

    Butyl Nitrate (BN) was examined by Small-Scale Safety and Thermal (SSST) Testing techniques to determine its sensitivity to impact, friction, spark and thermal exposure simulating handling and storage conditions. Under the conditions tested, the BN exhibits thermal sensitivity above 150 °C, and does not exhibit sensitive to impact, friction or spark.

  3. Preparation of L-Butyl Lactate via Transesterification by Using Nafion-H Catalyst

    Institute of Scientific and Technical Information of China (English)

    Wei LI; Guo Rong ZHENG; Ping LU

    2005-01-01

    Optically pure L-butyl lactate was synthesized by normal transesterification using nafion-H catalyst in moderate yield. Various reaction conditions were investigated, including the reaction temperature, reaction time, ratio of the starting material and amount of the nafion catalyst.

  4. Irradiation Initiated Grafting of Poly(butyl acrylate) onto Nano-sized Calcium Carbonate Particles

    Institute of Scientific and Technical Information of China (English)

    Chuan Guo MA; Min Zhi RONG; Ming Qiu ZHANG

    2005-01-01

    The present work reports the irradiation induced grafting polymerization onto nano-sized CaCO3 particles, mainly focusing on the effects of pretreatment with silane coupling agent. It is proved that poly(butyl acrylate) can be grafted onto the nanoparticles using the technical route suggested by the authors, and the silane treatment of the nanoparticles promotes the grafting polymerization.

  5. Tri(t-butyl)phosphine-assisted selective hydrosilylation of terminal alkynes

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A highly efficient and regio-/stereoselective method of hydrosilylating terminal alkynes was developed using Pt(DVDS)-tri(t-butyl) phosphine catalyst system at room temperature.Trans-products or alpha-products were obtained almost exclusively depending on the alkynes and silanes employed.

  6. 77 FR 27164 - Butylate, Clethodim, Dichlorvos, Dicofol, Isopropyl Carbanilate, et al.; Proposed Tolerance Actions

    Science.gov (United States)

    2012-05-09

    ... the nomenclature of specific tolerances for butylate, methomyl, and tralomethrin, and remove expired... permitted by the tolerance. In addition, EPA is proposing to revise the nomenclature of specific tolerances... May 17, 2011, cease all sales and distribution of dicofol end-use products by October 31, 2013,...

  7. A direct and sustainable synthesis of tertiary butyl esters enabled by flow microreactors.

    Science.gov (United States)

    Degennaro, Leonardo; Maggiulli, Daniela; Carlucci, Claudia; Fanelli, Flavio; Romanazzi, Giuseppe; Luisi, Renzo

    2016-08-01

    Tertiary butyl esters find large applications in synthetic organic chemistry. A straightforward method for the direct introduction of the tert-butoxycarbonyl group into a variety of organic compounds has been developed using flow microreactor systems. The resultant flow process was more efficient, versatile and sustainable compared to the batch.

  8. A new steroidal compound (β-sitosterol-3-O-butyl isolated from Caesalpinia gilliesii flowers

    Directory of Open Access Journals (Sweden)

    Samir Mohamed Osman

    2015-01-01

    Full Text Available Summary. The study aimed to evaluate the cytotoxic activity of total extracts from leaves, flowers and pods of Caesalpinia gilliesii (Fabaceae, Caesalpinoideae. In addition, a detailed phytochemical investigation of flower extracts was carried out to isolate and elucidate the structures of the bioactive compounds. Flower extract was the most cytotoxic against MCF7 and HepG2 cancer cells with IC50 values of 10 and 15.6 µg/mL, respectively. A new β-sitosterol-3-O-butyl was isolated from dichloromethane fraction of flowers together with another known sterol (daucosterol, and two flavonoids (isorhamnetin and isorhamnetin 3-O-rhamnoside. β-sitosterol-3-O-butyl was the most active compound against both HepG2 and MCF7 cells with IC50 values of 13.1 and 14.4 µg/mL, respectively. Isorhamnetin possesses a moderate antioxidant activity with an IC50 value 370 µg/mL as determined by DPPH radical scavenging assay.Industrial relevance. β-sitosterol-3-O-butyl and the other phytosterols are responsible for the cytotoxicity of the extracts which would correlate with the known abortifacient, antimalarial and anthelmintic properties, which can provide a cheap alternative drug.Keywords. Cytotoxicity, antioxidant; Caesalpinia gilliesii; β-sitosterol-3-O-butyl; daucosterol; isorhamnetin-3-O-rhamnoside

  9. Kinetic Study of the Reaction between Tert-butyl Hydrazine and Nitrous Acid

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The kinetic study of the reaction between tert-butyl hydrazine(TBH)and nitrous acid in nitric acid system is performed by spectrophotometry. The effect of some factors such as the concentration of TBH, the concentration of nitric acid, ionic strength, temperature and the

  10. A Chiral Macroscopic Force between Liquid of Butyl Alcohol and Copper Block

    Institute of Scientific and Technical Information of China (English)

    HU Yong-Hong; LIU Zhong-Zhu

    2008-01-01

    A non-zero macroscopic chirality-dependent force between a copper block and a vessel of homochiral molecules(butyl alcohol) is calculated quantitatively with the central field approximation. The magnitude of the force is estimated with the published limits of the scalar and pseudo-scalar coupling constants.

  11. A Case of Successful Ablation of a Gastrophrenic Fistula with n-Butyl-2-Cyanoacrylate

    Directory of Open Access Journals (Sweden)

    Ashish Mahajan

    2008-01-01

    Full Text Available A 79-year-old woman with a fistula between a subphrenic abscess and the fundus of the stomach was successfully treated with n-Butyl-2-Cyanoacrylate. Conservative management had failed. Clinical presentation, treatment progress and imaging findings by computed tomography scan, ultrasound, gastroscopy and fluoroscopy are presented, along with a brief review of the relevant literature.

  12. Enhanced diisobutene production in the presence of methyl tertiary butyl ether

    Science.gov (United States)

    Smith, L.A. Jr.

    1983-03-01

    In the liquid phase reaction of isobutene in the presence of resin cation exchange resins with itself in a C[sub 4] hydrocarbon stream to form dimers, the formation of higher polymers, oligomers, and co-dimer by-products is suppressed by the presence of 0.0001 to 1 mole per mole of isobutene of methyl tertiary butyl ether. 1 fig.

  13. Synthesis and characterization of birch wood xylan succinoylated in 1-n-butyl-3-methylimidazolium chloride

    DEFF Research Database (Denmark)

    Hansen, Natanya Majbritt Louie; Plackett, David

    2011-01-01

    The chemical modification of birch wood xylan was undertaken in the ionic liquid 1-n-butyl-3-methylimidazolium chloride (C4mimCl) using three different long-chain succinic anhydrides: n-octenyl succinic anhydride (n-OSA), n-dodecenyl succinic anhydride (n-DDSA) and n-octadecenyl succinic anhydrid...

  14. TREATMENT OF METHYL TERT-BUTYL ETHER CONTAMINATED WATER USING PHOTOCATALYSIS

    Science.gov (United States)

    The feasibility of photo-oxidation treatment of methyl tert-butyl ether (MTBE) in water was investigated in three ways, 1) using a slurry falling film photo-reactor, 2) a batch solar reactor system, and 3) a combination of air-stripping and gas phase photooxidation system. MTBE-c...

  15. Polypyrrole-coated styrene-butyl acrylate copolymer composite particles with tunable conductivity

    Institute of Scientific and Technical Information of China (English)

    HUANG Liyan; HOU Wenbo; LIU Zhengping; ZHANG Qingyue

    2005-01-01

    A series of near or monodisperse styrene-butyl acrylate (SBA) copolymer latex particles with different butyl acrylate contents were coated with polypyrrole. The structure of the SBA/PPy composites was characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), diffuse reflectance infrared Fourier transform spectroscopy (DRIFT), X-ray photoelectron spectroscopy (XPS), differential scanning calorimetry (DSC) and standard four-probe method. The core-shell morphology of the SBA/PPy composite particles was confirmed. The result of DSC showed that Tg of the composite is mainly determined by the core component. The effects of the concentration of polypyrrole, the butyl acrylate content in SBA copolymer and the nature of the counter-anion on the electrical conductivity of compression-moulded samples were studied. It was first found that the electrical conductivity of the samples can be tuned by varying the butyl acrylate content in SBA copolymer and the highest conductivity of the core-shell composite was 0.17 S·cm-1.

  16. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (Etbe) (Interagency Science Consultation Draft)

    Science.gov (United States)

    In September 2016, EPA released the draft IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE) for public comment and discussion. The draft assessment was reviewed internally by EPA and by other federal agencies and White House Offices before public release. Consistent ...

  17. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (Etbe) (Public Comment Draft)

    Science.gov (United States)

    In September 2016, the U.S. Environmental Protection Agency's (USEPA) released the draft Integrated Risk Information System (IRIS) Toxicological Review of Ethyl Tertiary Butyl Ether (ETBE). Consistent with the 2013 IRIS Enhancements, draft IRIS assessments are released prior to e...

  18. IRIS Toxicological Review of Ethyl Tertiary Butyl Ether (Etbe) (External Review Draft, 2009)

    Science.gov (United States)

    EPA is conducting a peer review and public comment of the scientific basis supporting the human health hazard and dose-response assessment of ethyl tertiary butyl ether (ETBE) that when finalized will appear on the Integrated Risk Information System (IRIS) database.

  19. Morphology and film formation of poly(butyl methacrylate)-polypyrrole core-shell latex particles

    NARCIS (Netherlands)

    Huijs, F; Lang, J

    2000-01-01

    Core-shell latex particles made of a poly(butyl methacrylate) (PBMA) core and a thin polypyrrole (PPy) shell were synthesized by two-stage polymerization. In the first stage, PBMA latex particles were synthesized in a semicontinuous process by free-radical polymerization. PBMA latex particles were l

  20. Liquid/air partition coefficients of methyl and ethyl T-butyl ethers, T-amyl methyl ether, and T-butyl alcohol.

    Science.gov (United States)

    Nihlen, A; Lof, A; Johanson, G

    1995-01-01

    Partition coefficients are essential to a description of the uptake and distribution of volatile substances in humans and in the development of physiologically based pharmacokinetic models. Liquid/air partition coefficients (lambda) of three ethers, methyl t-butyl ether (MTBE), ethyl t-butyl ether (ETBE), and t-amyl methyl ether (TAME) were determined in vitro by head space-gas chromatography. These ethers, and especially MTBE, are used in unleaded gasoline to enhance the oxygen and octane content, and to reduce the output of carbon monoxide during combustion. Partition coefficients of t-butyl alcohol (TBA), a metabolite of MTBE, were determined also. The liquids tested were fresh human blood, water (physiological saline), and olive oil. The (lambda)blood/air values were: 17.7 (95% confidence interval 17.0-18.4) for MTBE; 11.7 (11.3-12.1) for ETBE; and 17.9 (17.3-18.5) for TAME. Corresponding (lambda)water/air values were 15.2 (14.9-15.5), 8.39 (8.19-8.59), and 11.9 (11.7-12.1). The ethers have a higher affinity for oil, the values for (lambda)oil/air being 120 (114-125), 190 (183-197), and 337 (320-354), respectively. As expected, the (lambda)blood/air and (lambda)water/air for TBA were much higher than for the ethers, 462 (440-484) and 603 (590-617), respectively. The (lambda)oil/air was 168 (161-174) for TBA. The interindividual variability of the (lambda)blood/air (10 subjects) was calculated as the coefficient of variation, and estimated as: 14% for MTBE, 20% for ETBE, 20% for TAME, and 30% for TBA. No significant difference was seen in the (lambda)blood/air between the sexes.

  1. Biodegradation of the gasoline oxygenates methyl tert-butyl ether, ethyl tert-butyl ether, and tert-amyl methyl ether by propane-oxidizing bacteria.

    Science.gov (United States)

    Steffan, R J; McClay, K; Vainberg, S; Condee, C W; Zhang, D

    1997-11-01

    Several propane-oxidizing bacteria were tested for their ability to degrade gasoline oxygenates, including methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), and tert-amyl methyl ether (TAME). Both a laboratory strain and natural isolates were able to degrade each compound after growth on propane. When propane-grown strain ENV425 was incubated with 20 mg of uniformly labeled [14C]MTBE per liter, the strain converted > 60% of the added MTBE to 14CO2 in production of nearly stoichiometric amounts of tert-butyl alcohol (TBA), while the initial oxidation of TAME resulted in the production of tert-amyl alcohol. The methoxy methyl group of MTBE was oxidized to formaldehyde and ultimately to CO2. TBA was further oxidized to 2-methyl-2-hydroxy-1-propanol and then 2-hydroxy isobutyric acid; however, neither of these degradation products was an effective growth substrate for the propane oxidizers. Analysis of cell extracts of ENV425 and experiments with enzyme inhibitors implicated a soluble P-450 enzyme in the oxidation of both MTBE and TBA. MTBE was oxidized to TBA by camphor-grown Pseudomonas putida CAM, which produces the well-characterized P-450cam, but not by Rhodococcus rhodochrous 116, which produces two P-450 enzymes. Rates of MTBE degradation by propane-oxidizing strains ranged from 3.9 to 9.2 nmol/min/mg of cell protein at 28 degrees C, whereas TBA was oxidized at a rate of only 1.8 to 2.4 nmol/min/mg of cell protein at the same temperature.

  2. Synthesis, Resolution, and Enantiomeric Purity Assay of 2-n-Butylbutanedioic Acid 4-t-Butyl Esters

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Racemic 2-n-butylbutanedioic acid 4-t-butyl esters were synthesized from methyl hexanoate and t-butyl α-iodoacetate via alkylation and subsequently selective hydrolyzation. The (R)-and (S)-2-n-butylbutanedioic acid 4-t-butyl esters were obtained by the resolution of the above-mentioned racemic compounds with(S)-( - ) or(R)-( + )-α-methylbenzylamine, respectively. The e.e. values of the two optical active products were determined to be above 99% by HPLC after the formation of two pairs of diastereoisomers with ( R)-( + )-α-methylbenzylamine and (S)-phenylalanine methyl ester.

  3. Study on the antioxidative effect of antioxidant compound on low-calorie cocoa butter equivalent%复配抗氧化剂对低能量类可可脂抗氧化作用的研究

    Institute of Scientific and Technical Information of China (English)

    谭志强; 吴炜亮; 潘露云; 姜土; 郑建仙

    2012-01-01

    The antioxidant activities on low-calorie cocoa butter equivalent of butylated hydroxytoluene(BHT),phytic acid(PA)and Vitamin E(VE)were studied by Schaal experiment,with peroxide value as the evaluation index.Response surface methodology was used to optimize and determine the antioxidant compound.The results showed that the compositions of the optimized antioxidant compound were BHT 0.11‰,PA 0.11‰,VE 0.13‰ and every component of the antioxidant compound had obvious synergistic effect.The antioxidant activity of the optimized was much better,compared with that of single antioxidant.%采用Schaal烘箱加速氧化法,以过氧化值为评价指标,研究了二丁基羟基甲苯、植酸、维生素E三种抗氧化剂对低能量类可可脂的抗氧化效果。采用响应曲面法优化并确定了复配抗氧化剂的最优配方,结果表明:复配抗氧化剂的最优组成比例为BHT0.11‰,PA0.11‰,VE0.13‰,复配抗氧化剂各组分间具有显著的协同增效作用。通过比较最优复配抗氧化剂与单一抗氧化剂对低能量类可可脂的抗氧化效果,得出其抗氧化活性明显优于单一抗氧化剂。

  4. Solid-phase synthesis of thermolytic DNA oligonucleotides functionalized with a single 4-hydroxy-1-butyl or 4-phosphato-/thiophosphato-1-butyl thiophosphate protecting group.

    Science.gov (United States)

    Grajkowski, Andrzej; Ausín, Cristina; Kauffman, Jon S; Snyder, John; Hess, Sonja; Lloyd, John R; Beaucage, Serge L

    2007-02-02

    Several thermolytic CpG-containing DNA oligonucleotides analogous to 1 have been synthesized to serve as potential immunotherapeutic oligonucleotide prodrug formulations for the treatment of infectious diseases in animal models. Specifically, the CpG motif (GACGTT) of each DNA oligonucleotide has been functionalized with either the thermolabile 4-hydroxy-1-butyl or the 4-phosphato-/thiophosphato-1-butyl thiophosphate protecting group. This functionalization was achieved through incorporation of activated deoxyribonucleoside phosphoramidite 8b into the oligonucleotide chain during solid-phase synthesis and, optionally, through subsequent phosphorylation effected by phosphoramidite 9. Complete conversion of CpG ODNs hbu1555, psb1555, and pob1555 to CpG ODN 1555 (homologous to 2) occurred under elevated temperature conditions, thereby validating the function of these diastereomeric oligonucleotides as prodrugs in vitro. Noteworthy is the significant increase in solubility of CpG ODN psb1555 and CpG pob1555 in water when compared to that of neutral CpG ODN fma1555 (homologous to 1).

  5. No Promoting Effect of Ethyl Tertiary-butyl Ether (ETBE) on Rat Urinary Bladder Carcinogenesis Initiated with N-Butyl-N-(4-hydroxybutyl)nitrosamine.

    Science.gov (United States)

    Hagiwara, Akihiro; Imai, Norio; Doi, Yuko; Suguro, Mayuko; Kawabe, Mayumi; Furukawa, Fumio; Nagano, Kasuke; Fukushima, Shoji

    2013-12-01

    The effects of ethyl tertiary-butyl ether (ETBE) on two-stage urinary bladder carcinogenesis in male F344 rats initiated with N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) were investigated at various dose levels with regard to possible promoting activity. Groups of 30 rats were given drinking water containing 500 ppm BBN, as an initiator, for 4 weeks and starting one week thereafter received ETBE by gavage (daily, 7 days/week) at dose levels of 0 (control), 100, 300, 500 or 1000 mg/kg/day until experimental week 36. No statistically significant differences in incidences of preneoplastic lesions, papillomas, and carcinomas of the urinary bladder were evident in rats treated with 100-1000 mg/kg/day ETBE as compared with control values. Furthermore, the average numbers of preneoplastic or neoplastic lesions per unit length of basement membrane in rats given 100-1000 mg/kg/day ETBE were also comparable to control values. However, papillomatosis of the urinary bladder was found in 4 out of 30 rats (13%) in the group given 1000 mg/kg/day ETBE, and soft stones in the urinary bladder were found in 3 out of these 4 rats. The results thus demonstrated that ETBE did not exert promotional activity on urinary bladder carcinogenesis. However, papillomatosis of the urinary bladder developed in small numbers of the rats given ETBE at 1000 mg/kg/day but not in rats given 500 mg/kg/day or lower doses.

  6. Selection and identification of bacterial strains with methyl-tert-butyl ether, ethyl-tert-butyl ether, and tert-amyl methyl ether degrading capacities.

    Science.gov (United States)

    Purswani, Jessica; Pozo, Clementina; Rodríguez-Díaz, Marina; González-López, Jesús

    2008-11-01

    Nine bacterial strains isolated from two hydrocarbon-contaminated soils were selected because of their capacity for growth in culture media amended with 200 mg/L of one of the following gasoline oxygenates: Methyl-tert-butyl ether (MTBE), ethyl-tert-butyl ether (ETBE), and tert-amyl methyl ether (TAME). These strains were identified by amplification of their 16S rRNA gene, using fDl and rD1 primers, and were tested for their capacity to grow and biotransform these oxygenates in both mineral and cometabolic media. The isolates were classified as Bacillus simplex, Bacillus drentensis, Arthrobacter sp., Acinetobacter calcoaceticus, Acinetobacter sp., Gordonia amicalis (two strains), Nocardioides sp., and Rhodococcus ruber. Arthrobacter sp. (strain MG) and A. calcoaceticus (strain M10) consumed 100 (cometabolic medium) and 82 mg/L (mineral medium) of oxygenate TAME in 21 d, respectively, under aerobic conditions. Rhodococcus ruber (strain E10) was observed to use MTBE and ETBE as the sole carbon and energy source, whereas G. amicalis (strain T3) used TAME as the sole carbon and energy source for growth. All the bacterial strains transformed oxygenates better in the presence of an alternative carbon source (ethanol) with the exception of A. calcoaceticus (strain M10). The capacity of the selected strains to remove MTBE, ETBE, and TAME looks promising for application in bioremediation technologies.

  7. Separation of the Ternary System of Methanol/Methyl Butyl Ether/1-Butylchloride

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The separation of ternary methanol/methyl butyl ether/1-butylchloride mixtures was investigated, which are the main components of the waste liquid. After preliminary studies on the ternary system, the integrated process of extraction and distillation was put forward to separate the ternary system. The results show that methanol can be removed from the mixtures by extraction using water as the extracting agent. Through distillation of extract and dried raffinate respectively, methanol,methyl butyl ether and 1-butylchloride can be separated and recovered. In addition, the optimal volume for the extracting agent and effects of reflux ratio on the yield of product were also studied. The optimal volume ratio of the extracting agent to material is 1: 3.5, and the yield of the product increases with the increase of reflux ratio.

  8. Collagen-Immobilized Lipases Show Good Activity and Reusability for Butyl Butyrate Synthesis.

    Science.gov (United States)

    Dewei, Song; Min, Chen; Haiming, Cheng

    2016-11-01

    Candida rugosa lipases were immobilized onto collagen fibers through glutaraldehyde cross-linking method. The immobilization process has been optimized. Under the optimal immobilization conditions, the activity of the collagen-immobilized lipase reached 340 U/g. The activity was recovered of 28.3 % by immobilization. The operational stability of the obtained collagen-immobilized lipase for hydrolysis of olive oil emulsion was determined. The collagen-immobilized lipase showed good tolerance to temperature and pH variations in comparison to free lipase. The collagen-immobilized lipase was also applied as biocatalyst for synthesis of butyl butyrate from butyric acid and 1-butanol in n-hexane. The conversion yield was 94 % at the optimal conditions. Of its initial activity, 64 % was retained after 5 cycles for synthesizing butyl butyrate in n-hexane.

  9. Di-n-butylbis(N-n-butyl-N-ethyldithiocarbamato-κStin(IV

    Directory of Open Access Journals (Sweden)

    Seik Weng Ng

    2009-05-01

    Full Text Available The Sn atom in the title compound, [Sn(C4H92(C7H14NS22], exists in a tetrahedral C2S2Sn coordination geometry. The geometry is distorted towards skew-trapezoidal-bipyramidal owing to the proximity of the double-bond S atoms [Sn—S = 2.521 (2 and Sn...S = 2.933 (2 Å]. The Sn atom lies on a special position of mm2 site symmetry and the tin-bound n-butyl chain is disordered about a mirror plane. The ethyl and n-butyl groups of the dithiocarbamate unit are disordered about another mirror plane.

  10. Pulmonary embolism after endoscopic injection with N-butyl-2-cyanoacrylate for gastric varices

    Directory of Open Access Journals (Sweden)

    Gabriela Robaina

    2016-12-01

    Full Text Available Gastric varices occur in one-third of patients with portal hypertension. Bleeding from gastric varices remains a significant cause of death. Currently the first-line of treatment for gastric varices is endoscopic obliteration with N-butyl-2-cyanoacrylate. Though relatively safe, this option has several well-known complications. We report the case of a 61-year-old male patient with cryptogenic cirrhosis, who presented with fever, tachycardia and hypoxemia after endoscopic obliteration with N-butyl-2-cyanoacrylate. Radiographic findings were consistent with pulmonary embolism of the sclerosing substance. The aim of this case report is to emphasize the clinical and radiological findings of this complication in order to distinguish it from other similar medical conditions and prevent a delay in diagnosis

  11. Thermodynamic Properties of Hydrogen + Tetra-n-Butyl Ammonium Bromide Semi-Clathrate Hydrate

    Directory of Open Access Journals (Sweden)

    Shunsuke Hashimoto

    2010-01-01

    Full Text Available Thermodynamic stability and hydrogen occupancy on the hydrogen + tetra-n-butyl ammonium bromide semi-clathrate hydrate were investigated by means of Raman spectroscopic and phase equilibrium measurements under the three-phase equilibrium condition. The structure of mixed gas hydrates changes from tetragonal to another structure around 95 MPa and 292 K depending on surrounding hydrogen fugacity. The occupied amount of hydrogen in the semi-clathrate hydrate increases significantly associated with the structural transition. Tetra-n-butyl ammonium bromide semi-clathrate hydrates can absorb hydrogen molecules by a pressure-swing without destroying the hydrogen bonds of hydrate cages at 15 MPa or over.

  12. Dissolution of wood flour and lignin in 1-butyl-3-methyl-1-imidazolium chloride

    Directory of Open Access Journals (Sweden)

    Yasmin Nasiri Khonsari

    2013-10-01

    Full Text Available The ionic solvent, 1-butyl-3-methyl imidazolium chloride was used to dissolve the samples. Two lignocellulosic material including bagasse soda lignin and Populus deltoides wood flour were used. One gram of samples were dissolved in 10 ml ionic solvent, 1-butyl-3-methyl- imidazolium chloride at 70 ºC for 72 h while stirring with a magnetic stirrer. The wood flour and lignin samples were acetylated with addition of acetic anhydride to each container with a ratio of 0.25 ml/ 0.25 ml. The samples were heated for 3 days at 110 ° C. Two control samples (without acetylation and two treatments (acetylation were used. The functional groups were determined using FT-IR Spectrometer. The number and type of carbon and their structure were examined using 13CNMR Spectrometer. The guaiacyl, syringyl, coniferyl alcohol and biphenyls structures were identified.

  13. Aging of Weapon Seals – An Update on Butyl O-ring Issues

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Mark H.

    2011-07-13

    During testing under the Enhanced Surveillance Campaign in 2001, preliminary data detected a previously unknown and potentially serious concern with recently procured butyl o-rings on several programs. All butyl o-rings molded from a proprietary formulation throughout the period circa 1999 through 2001 had less than a full cure. Engineering judgment was that under curing is detrimental and could possibly lead to sub-optimum performance or, in the worst case, premature seal failure. An aging study was undertaken to ensure that suspect o-rings installed in the stockpile will retain sufficient sealing force for a minimum ten-year service life. A new prediction model developed for this study indicates suspect o-rings do not need to be replaced before the ten-year service life. Long-term testing results are reported on a yearly basis to validate the prediction model. This report documents the aging results for the period September 2002 to January 2011.

  14. The oxidation of 2,6-di-tert-butyl-4-methylphenol

    Science.gov (United States)

    Yohe, G.R.; Dunbar, J.E.; Pedrotti, R.L.; Scheidt, F.M.; Lee, F.G.H.; Smith, E.C.

    1956-01-01

    The products formed in the oxidation of 2,6-di-tert-butyl-4-methylphenol with oxygen and sodium hydroxide at about 100?? are 3,5-di-tert-butyl-4-hydroxybenzaldehyde, trimethylacetic acid, an acidic compound C14H22O3, and probably 2,6-di-tert-butylbenzoquinone (which was actually isolated in the similar oxidation of the above-named benzaldehyde), in addition to compounds previously reported. Some of the properties of C14H22O3 are given, and the oxidation of it to 2,3-di-tert-butylsuccinic anhydride is described, but assignment of structure is reserved pending the completion of more experimental work.

  15. MICROWAVE-ASSISTED PREPARATION OF 1-BUTYL-3-METHYLIMIDAZOLIUM TETRACHLOROGALLATE AND ITS CATALYTIC USE IN ACETAL FORMATION UNDER MILD CONDITIONS

    Science.gov (United States)

    1-Butyl-3-methylimidazolium tetrachlorogallate, [bmim][GaCl4], prepared via microwave-assisted protocol, is found to be an active catalyst for the efficient acetalization of aldehydes under mild conditions.

  16. Small-angle neutron scattering studies of sodium butyl benzene sulfonate aggregates in aqueous solution

    Indian Academy of Sciences (India)

    O R Pal; V G Gaikar; J V Joshi; P S Goyal; V K Aswal

    2004-08-01

    The aggregation behaviour of a hydrotrope, sodium -butyl benzene sulfonate (Na-NBBS), in aqueous solutions is investigated by small-angle neutron scattering (SANS). Nearly ellipsoidal aggregates of Na-NBBS at concentrations well above its minimum hydrotrope concentration were detected by SANS. The hydrotrope seems to form self-assemblies with aggregation number of 36–40 with a substantial charge on the aggregate. This aggregation number is weakly affected by the hydrotrope concentration.

  17. (2-tert-Butyl-5-hydroxymethyl-1,3-dioxan-5-ylmethanol

    Directory of Open Access Journals (Sweden)

    Berenice Vargas

    2012-07-01

    Full Text Available In the title compound, C10H20O4, the dioxane ring adopts a chair conformation. The tert-butyl group occupies an equatorial position, and is staggered with respect to the O atoms of the dioxane ring. In the crystal, molecules are connected by O—H...O hydrogen-bonds into zigzag chains of R44(8 and R22(12 ring motifs that run parallel to the a axis.

  18. 1-[(E-2-(5-tert-Butyl-2-hydroxyphenyldiazen-1-yl]naphthalen-2-ol

    Directory of Open Access Journals (Sweden)

    Hassiba Bougueria

    2014-02-01

    Full Text Available The non-H atoms of the title compound, C20H20N2O2, is located on a mirror plane except two methyl groups of the tert-butyl group. Intramolecular N—H...O hydrogen bonds exist between the hydroxy and diazenyl groups. In the crystal, molecules are linked by weak C—H...O hydrogen bonds into supramolecular chains running along the a-axis direction.

  19. Vinyl Acetate/butyl acrylate/acrylate Research of Ternary Soap-free Emulsion Polymerization

    Directory of Open Access Journals (Sweden)

    Xiao Li-guang

    2016-01-01

    Full Text Available Through the vinyl acetate/butyl acrylate/acrylic acrylic emulsion preparation without soap vinegar, with solid content, gel, emulsion stability and film forming properties and tensile strength as the main index to study the effect of raw materials on the properties of emulsion. Through the infrared spectrometer soap-free emulsion for microscopic analysis research. Study of the ternary soap-free vinegar acrylic emulsion with good performance.

  20. Synthesis and characterization of tris[butyl-(1-methyl-3-phenyl-propyl-dithiocarbamato]-cobalt(III seskvitoluene

    Directory of Open Access Journals (Sweden)

    TIBOR SABO

    2002-02-01

    Full Text Available A new bidentate ligand butyl-(1-methyl-3-phenyl-propyl-dithiocarbamate (bmFpdtc was prepared, as the sodium salt. In the reaction of hexaaminecobalt(III chloride with NabmFpdtc, the corresponding tris[butyl-(1-methyl-3-phenyl-propyl-dithiocarbamato]cobalt(III, [Co(bmFpdtc3] complex was prepared. The complex was characterized by elemental analysis, infrared, electronic absorption, 1H and 13C-NMR spectroscopy.

  1. Reaction kinetics for synthesis of sec-butyl alcohol catalyzed by acid-functionalized ionic liquid

    Institute of Scientific and Technical Information of China (English)

    Ting Qiu; Wenli Tang; Chenggang Li; Chengming Wu; Ling Li

    2015-01-01

    The acid-functionalized ionic liquid ([HSO3Pmim]HSO4) was synthesized by a two-step method. Nuclear magnetic resonance (NMR) and Fourier transform infrared spectroscopy (FT-IR) show that the synthesis method is feasible and high purity of ionic liquid can be obtained. Using [HSO3Pmim]HSO4 as the catalyst, we studied the reaction kinetics of synthesizing sec-butyl alcohol from sec-butyl acetate and methanol by transesterification in a high-pressure batch reactor. The effects of temperature, initial molar ratio of methanol to ester, and catalyst concentration on the conversion of sec-butyl acetate were studied. Based on its possible reaction mechanism, a ho-mogeneous kinetic model was established. The results show that the reaction heatΔH is 10.94 × 103 J·mol−1, so the reaction is an endothermic reaction. The activation energies Ea+and Ea−are 60.38 × 103 and 49.44 × 103 J·mol−1, respectively.

  2. Vapour phase alkylation of ethylbenzene with -butyl alcohol over mesoporous Al-MCM-41 molecular sieves

    Indian Academy of Sciences (India)

    V Umamaheswari; M Palanichamy; Banumathi Arabindoo; V Murugesan

    2002-06-01

    The alkylation of ethylbenzene with -butyl alcohol was studied over Al-MCM-41 (Si/Al = 50 and 90) and Al, Mg-MCM-41 (Si/(Al + Mg) =50) in the vapour phase from 200 to 400°C. The products were --butylethylbenzene (--BEB), --butylvinylbenzene (--BVB) and --butylethylbenzene ( --BEB). Ethylbenzene conversion decreased with increase in temperature and increase in the ethylbenzene content of the feed. The reaction between the freely diffusing ethylbenzene in the channel and the -butyl cations remaining as charge compensating ions yielded --BEB. --BVB, an unexpected product in this investigation, was produced by dehydrogenation of --BEB over alumina particles present in the channels of the molecular sieves. Adsorption of ethylbenzene on Brønsted acid sites and its subsequent reaction with very closely adsorbed -butyl cations proved to be necessary to obtain --BEB. Though --BEB was obtained, the corresponding --butylvinylbenzene was not observed in this study. Study of time durations indicated rapid and slow catalyst deactivation at lower and higher streams respectively.

  3. Comprehensive testing to measure the response of butyl rubber to Hanford tank waste simulant

    Energy Technology Data Exchange (ETDEWEB)

    NIGREY,PAUL J.

    2000-05-01

    This report presents the findings of the Chemical Compatibility Program developed to evaluate plastic packaging components that may be incorporated in packaging mixed-waste forms for transportation. Consistent with the methodology outlined in this report, the authors performed the second phase of this experimental program to determine the effects of simulant Hanford tank mixed wastes on packaging seal materials. That effort involved the comprehensive testing of five plastic liner materials in an aqueous mixed-waste simulant. The testing protocol involved exposing the materials to {approximately}143, 286, 571, and 3,670 krad of gamma radiation and was followed by 7-, 14-, 28-, 180-day exposures to the waste simulant at 18, 50, and 60 C. Butyl rubber samples subjected to the same protocol were then evaluated by measuring seven material properties: specific gravity, dimensional changes, mass changes, hardness, compression set, vapor transport rates, and tensile properties. From the analyses, they determined that butyl rubber has relatively good resistance to radiation, this simulant, and a combination of these factors. These results suggest that butyl rubber is a relatively good seal material to withstand aqueous mixed wastes having similar composition to the one used in this study.

  4. Synthesis and Structure of an Octopus-like Octapropargyl Tetra-iso-butyl-resorcin[4]arene

    Institute of Scientific and Technical Information of China (English)

    LIU Xiang; LIU Yu-Jie; ZHANG Qian-Feng

    2005-01-01

    Treatment of tetra-iso-butyl-resorcin[4]arene 1 with propargyl bromide in the presence of K2CO3 as base gave an octopus-like octapropargyl tetra-iso-butyl-resorcin[4]arene 2 (C68H72O8, Mr = 1017.26) in a quantitative yield.Single-crystal structure of 2 was determined by X-ray crystallography.2 crystallizes in the monoclinic system, space group P21/n with a =13.3247(6), b = 24.7929(11), c = 19.1810(9)(。A), β= 109.272(1)°, V= 5981.5(5)(。A)3, Dc.= 1.130 g/cm3, μ = 0.073 mm-1, F(000) = 2176 and Z = 4.Overall structure of 2 reveals an octopus-like resorcinarene with eight propargyl groups in different directions.The resorcinarene adopts the boat conformation where the iso-butyl residues act as four-legged piano stool.The two opposite aryl rings of the macrocyclic framework are almost coplanar, and the two others facing each other are perpendicular to this plane.

  5. Synthesis and Characterization of a Gasoline Oxygenate, Ethyl tert-Butyl Ether

    Science.gov (United States)

    Donahue, Craig J.; D'Amico, Teresa; Exline, Jennifer A.

    2002-06-01

    A laboratory procedure involving the synthesis and characterization of ethyl tert-butyl ether (ETBE) is described. This experiment has been used in a general chemistry sequence that includes a section on organic chemistry, but is also well suited for an introductory organic chemistry laboratory course. ETBE is prepared by the acid-catalyzed reaction of tert-butyl alcohol with ethyl alcohol. The product is recovered as a low-boiling azeotrope and purified by liquid liquid extraction with water. By using gas chromatography and IR spectroscopy to examine both the crude and the purified products, students can see how much the purity of their sample improves. They can also appreciate the value of these methods (especially GC) as tools to establish purity. Student results are presented. The use of ETBE and its more prominent cousin methyl tert-butyl ether (MTBE) as gasoline oxygenates has become very controversial because they have polluted underground water supplies. This lab permits students to prepare a compound that has a real use and regularly makes headlines in the news. This lab experiment is part of an effort to develop a general chemistry sequence for engineering students using the theme of "Chemistry and the Automobile".

  6. Chemistry and in vitro antioxidant activity of volatile oil and oleoresins of black pepper (Piper nigrum).

    Science.gov (United States)

    Kapoor, I P S; Singh, Bandana; Singh, Gurdip; De Heluani, Carola S; De Lampasona, M P; Catalan, Cesar A N

    2009-06-24

    Essential oil and oleoresins (ethanol and ethyl acetate) of Piper nigrum were extracted by using Clevenger and Soxhlet apparatus, respectively. GC-MS analysis of pepper essential oil showed the presence of 54 components representing about 96.6% of the total weight. beta-Caryophylline (29.9%) was found as the major component along with limonene (13.2%), beta-pinene (7.9%), sabinene (5.9%), and several other minor components. The major component of both ethanol and ethyl acetate oleoresins was found to contain piperine (63.9 and 39.0%), with many other components in lesser amounts. The antioxidant activities of essential oil and oleoresins were evaluated against mustard oil by peroxide, p-anisidine, and thiobarbituric acid. Both the oil and oleoresins showed strong antioxidant activity in comparison with butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) but lower than that of propyl gallate (PG). In addition, their inhibitory action by FTC method, scavenging capacity by DPPH (2,2'-diphenyl-1-picrylhydrazyl radical), and reducing power were also determined, proving the strong antioxidant capacity of both the essential oil and oleoresins of pepper.

  7. Theoretical simulations on the antioxidant mechanism of naturally occurring flavonoid: A DFT approach

    Science.gov (United States)

    Praveena, R.; Sadasivam, K.

    2016-05-01

    Synthetic antioxidants such as butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) are found to be toxic, hence non-carcinogenic naturally occurring radical scavengers especially flavonoids have gained considerable importance in the past two decades. In the present investigation, the radical scavenging activity of C-glycosyl flavonoids is evaluated using theoretical approach which could broaden its scope in therapeutic applications. Gas and solvent phase studies of structural and molecular characteristics of C-glycosyl flavonoid, isovitexin is investigated through hydrogen atom transfer mechanism (HAT), Electron transfer-proton transfer (ET-PT) and Sequential proton loss electron transfer (SPLET) by Density functional theory (DFT) using hybrid parameters. The computed values of the adiabatic ionization potential, electron affinity, hardness, softness, electronegativity and electrophilic index indicate that isovitexin possess good radical scavenging activity. The behavior of different -OH groups in polyphenolic compounds is assessed by considering electronic effects of the neighbouring groups and the overall geometry of molecule which in turn helps in analyzing the antioxidant capacity of the polyphenolic molecule. The studies indicate that the H-atom abstraction from 4'-OH site is preferred during the radical scavenging process. From Mulliken spin density analysis and FMOs, B-ring is found to be more delocalized center and capable of electron donation. Comparison of antioxidant activity of vitexin and isovitexin leads to the conclusion that isovitexin acts as a better radical scavenger. This is an evidence for the importance of position of glucose unit in the flavonoid.

  8. Synthesis and antioxidant properties of diphenylmethane derivative bromophenols including a natural product.

    Science.gov (United States)

    Balaydin, Halis Türker; Gülçin, Ílhami; Menzek, Abdullah; Göksu, Süleyman; Şahin, Ertan

    2010-10-01

    Bromination of bis(3,4-dimethoxyphenyl)methanone (5) gave four products (6-9) with mono, di, tri, and tetra Br under different conditions. Reduction and demethylation reactions of product 9 with tetra Br were performed, consecutively and a natural product, 5,5'-methylene bis(3,4-dibrombenzene-1,2-diol) (1), was obtained with a 53% yield. Five derivatives, (13-17) (bromophenols), of 1 were also synthesised. The antioxidant and radical scavenging activities of bromophenols 1 and 13-17 were determined by employing various in vitro assays such as 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH(*)), 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid (ABTS(*+)), N,N-dimethyl-p-phenylenediamine dihydrochloride radical cation (DMPD(*+)), and superoxide anion radical (O(2)(*-)) scavenging, reducing ability determination by the Fe(3+)-Fe(2+) and Cu(2+)-Cu(+) cupric reducing antioxidant capacity (CUPRAC) transformation methods, hydrogen peroxide scavenging, and ferrous ion (Fe(2+)) chelating activities. Moreover, these activities were compared to those of synthetic standard antioxidant compounds such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), alpha-tocopherol, and trolox. The results showed that the synthesised bromophenols had effective antioxidant power.

  9. Different mechanisms of formation of glutathione-protein mixed disulfides of diamide and tert-butyl hydroperoxide in rat blood.

    Science.gov (United States)

    Di Simplicio, P; Lupis, E; Rossi, R

    1996-03-15

    The mechanisms of glutathione-protein mixed disulfide (GSSP) formation caused by diamide and tert-butyl hydroperoxide were studied in rat blood after in vitro treatment in the 0.3-4 mM dose range. tert-Butyl hydroperoxide formed GSSP, via GSSG, according to the reaction, GSSG + PSH --> GSSP + GSH, whereas diamide reacted first with protein SH groups, giving PS-diamide adducts and then, after reaction with GSH, GSSP. Moreover, after diamide treatment, GSSP patterns were characterized by a much slower or irreversible dose-related return to basal levels in comparison with those observed with tert-butyl hydroperoxide, always reversible. Experiments with purified hemoglobin revealed the existence of a large fraction of protein SH groups which formed GSSP and had a higher reactivity than GSH. Experiments on glucose consumption and role of various erythrocyte enzymes, carried out to explain the inertness of GSSP to reduction after treatment of blood with diamide, were substantially negative. Other tests carried out to confirm the efficiency of the enzymatic machinery of blood samples successively treated with diamide and tert-butyl hydroperoxide, indicated that GSSP performed by diamide was difficult to reduce, whereas those generated by tert-butyl hydroperoxide were reversible as normal. Our results suggest that a fraction of GSSP generated by diamide is different and less susceptible to reduction than that obtained with tert-butyl hydroperoxide.

  10. Antioxidant activity of wild edible plants in the Black Sea Region of Turkey

    Directory of Open Access Journals (Sweden)

    Özen, Tevfik

    2010-03-01

    Full Text Available The antioxidative activity of the 80% ethanol extract obtained from eleven commonly consumed wild edible plants was determined according to the phosphomolybdenum method, reducing power, metal chelating, superoxide anion and free radical scavenging activity and compared to standard compounds such as butylated hydroxyanisole (BHA, butylated hydroxytoluene (BHT and trolox. Total phenolic compounds, flavonoids, and anthocyanins in the extracts were also measured. Trachystemon orientalis, Vaccinium mrytillus, Rumex acetosella Polygonum amphibium, Beta vulgaris, and Similax Excelsa had the highest antioxidant capacities. Overall results showed that these plants can serve as good sources of bioactive polyphenols in the human diet and can be regarded as good candidates for nutritional supplement formulations due to their high concentrations of total phenolic compounds, flavonoids and anthocyanins as well as their strong antioxidant activity.La actividad antioxidante de extractos etanólicos al 80%, obtenidos de once plantas salvajes comúnmente consumidas, fue determinada por el método del fosfomolibdeno, poder reductor, actividad quelatante de metales, actividad captadora de aniones superóxidos y actividad captadora de radicales libres, y comparada con compuestos patrones tales como el butil hidroxianisol (BHA, butil hidroxitolueno (BHT y Trolox. El contenido de fenoles totales, flavonoides y antocianinas en el extracto fue también determinado. Trachystemon orientalis, Vaccinium mrytillus, Rumex acetosella Polygonum amphibium, Beta vulgaris, y Similax Excelsa tienen las capacidades antioxidantes más altas. En general, los resultados muestran que estas plantas pueden servir como una buena fuente de polifenoles bioactivos en la dieta humana, y pueden ser considerados como buenos candidatos para su uso como suplemento nutricional en formulaciones debido a su alta concentración en fenoles, flavonoides y antocinainas y a su fuerte actividad

  11. 5-tert-Butyl-2-[5-(5-tert-butyl-1,3-benzoxazol-2-yl-2-thienyl]-1,3-benzoxazole

    Directory of Open Access Journals (Sweden)

    Fang-Fang Jian

    2008-12-01

    Full Text Available The title compound, C26H26N2O2S, was prepared by the reaction of thiophene-2,5-dicarboxylic acid and 2-amino-4-tert-butylphenol. One of the tert-butyl groups is disordered over two conformations, with occupancies of 0.539 (1 and 0.461 (2. The two 1,3-benzoxazole rings are almost planar, with dihedral angles of 0.83 (18 and 1.64 (17° between the five- and six-membered rings. The thiophene ring makes dihedral angles of 21.54 (19 and 4.49 (18° with the planes of the five-membered oxazole rings. The crystal packing is controlled by π–π stacking interactions involving the thiophene and benzene rings, with a centroid–centroid distance of 3.748 (2 Å.

  12. Removal of Methyl Tert-Butyl Ether (MTBE from Contaminated Water by Photocatalytic Process

    Directory of Open Access Journals (Sweden)

    A Eslami

    2009-06-01

    Full Text Available "nBackground: Methyl tert-butyl ether (MTBE has been commercially used as an octane enhancer to replace tetraethyl lead in gasoline since 1979. The high mobility, water solubility, and resistance to natural attenuation associated with MTBE may re­sult in contamination of ground and surface waters. In this investigation the degradation of aqueous MTBE at relatively high concentrations was studied by UV-vis/TiO2/O2 photocatalytic process. The effect of important operational parameters such as pH, oxygen flow, catalyst loading, and irradiation time were also studied."nMethods:Concentration of MTBE and intermediates such as tert-butyl formate (TBF and tert-butyl alcohol (TBA were meas­ured using a gas chromatograph equipped with flam ionization detector and combined with headspace sampler."nResults: The time required for complete degradation increased from 15 to 150 min, when the initial concentration was in­creased from 10 to 500 mg/L. The first order rate constant for degradation of MTBE from the hydroxyl radical was esti­mated to be 0.266 to 0.033 min-1 as the concentration increased from 10 to 500 mg/L. Study on the overall mineralization moni­tored by total organic carbon (TOC analysis showed that in the initial concentration of 100 mg/L MTBE, complete min­eralization was obtained after 110 min under UV-vis/TiO2/O2 photocatalytic process."nConclusion: The data presented in this paper clearly indicate that UV/TiO2/O2 advanced oxidation process provides an effi­cient treatment alternative for the remediation of MTBE contaminated water.  

  13. Effect of layered silicate on the barrier properties of cured butyl rubber

    Energy Technology Data Exchange (ETDEWEB)

    Krzeminska, S [Central Institute for Labour Protection - National Research Institute, Department of Personal Equipment, Wierzbowa 48, 90-133 Lodz (Poland); Rzymski, W M [Technical University of Lodz, Institute of Polymer and Dye Technology, Stefanowskiego 12/16, 90-924 Lodz (Poland)], E-mail: sykrz@ciop.lodz.pl

    2009-01-01

    The aim of the study was to investigate the effect of layered silicate nanofiller (bentonite: Nanofil 15, Poro Additive) on the barrier properties of non-polar butyl rubber (the IIR, BK 1675 N brand) conventionally cured with sulphur in respect of selected organic solvents. The barrier properties were assessed on the basis of determination of standarized breakthrough time for cured IIR exposed to the selected solvents with different thermodynamic affinities to IIR, i.e. polar butyl acetate and non-polar cyclohexane. In the case of the non-polar solvent - cyclohexane - no effect of the content of the layered silicate (5 - 20 phr) on improvement of barrier properties of the tested IIR vulcanizates was observed. In contrast, a favorable effect of the silicate nanofiller was observed in the case of the polar solvent - butyl acetate, for which the breakthrough time tested for filler-containing vulcanizate (10 - 20 phr) reached 160 -200 min, whereas the breakthrough time obtained for unfilled vulcanizate was 129 min only. The testing of barrier properties of IIR vulcanizates containing various fillers (layered silicate Nanofil 15 and active silica Ultrasil VN3) added in the amount of 20 phr, indicate the favorable effect of layered silicate only in tests with the polar solvent used (an increase in breaktrhough time from 129 to 164 min). Contrary, the presence of conventional silica leads to decrease of breakthrough time (to 118 min). In the case of the non-polar solvent, no effect of the filler type on barrier properties of the tested vulcanizates was observed.

  14. Forensic analysis of tertiary-butyl alcohol (TBA) detections in a hydrocarbon-rich groundwater basin.

    Science.gov (United States)

    Quast, Konrad W; Levine, Audrey D; Kester, Janet E; Fordham, Carolyn L

    2016-04-01

    Tertiary-butyl alcohol (TBA), a high-production volume (HPV) chemical, was sporadically detected in groundwater and coalbed methane (CBM) wells in southeastern Colorado's hydrocarbon-rich Raton Basin. TBA concentrations in shallow water wells averaged 75.1 μg/L, while detections in deeper CBM wells averaged 14.4 μg/L. The detection of TBA prompted a forensic investigation to try to identify potential sources. Historic and recent data were reviewed to determine if there was a discernable pattern of TBA occurrence. Supplemental samples from domestic water wells, monitor wells, CBM wells, surface waters, and hydraulic fracturing (HF) fluids were analyzed for TBA in conjunction with methyl tertiary-butyl ether (MTBE) and ethyl tertiary-butyl ether (ETBE), proxies for evidence of contamination from reformulated gasoline or associated oxygenates. Exploratory microbiological sampling was conducted to determine if methanotrophic organisms co-occurred with TBA in individual wells. Meaningful comparisons of historic TBA data were limited due to widely varying reporting limits. Mapping of TBA occurrence did not reveal any spatial patterns or physical associations with CBM operations or contamination plumes. Additionally, TBA was not detected in HF fluids or surface water samples. Given the widespread use of TBA in industrial and consumer products, including water well completion materials, it is likely that multiple diffuse sources exist. Exploratory data on stable isotopes, dissolved gases, and microbial profiling provide preliminary evidence that methanotrophic activity may be producing TBA from naturally occurring isobutane. Reported TBA concentrations were significantly below a conservative risk-based drinking water screening level of 8000 μg/L derived from animal toxicity data.

  15. Isobaric vapor-liquid equilibria in the system methyl propanoate + n-butyl alcohol

    Energy Technology Data Exchange (ETDEWEB)

    Susial, P.; Ortega, J. (Univ. de Las Palmas de Gran Canaria, Canary Islands (Spain). Lab. de Termodinamica y Fisicoquimica)

    1993-10-01

    Isobaric vapor-liquid equilibria were determined at 74.66, 101.32, and 127.99 kPa for binary mixtures containing methyl propanoate + n-butyl alcohol by using a dynamic still with vapor and liquid circulation. No azeotrope was detected. The data were found to be thermodynamically consistent according to the point to point test. Application of the group-contribution models ASOG, UNIFAC, and modified UNIFAC to the activity coefficients at the three pressures studied gives average errors of less than 10%, 11%, and 3%, respectively.

  16. Kinetic Study of Np(Ⅵ) Reduction With Tert-butyl Hydrazine

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Tert-butyl hydrazine(TBH) is a new salt free reductant, it can effectively reduce Np(Ⅵ) to Np(Ⅴ) but reduce Pu(Ⅳ)very slowly. Further more, it has the highest ratio of rate constant for Np(Ⅵ) reduction to the rate constant for Pu(Ⅳ) reduction in hydrazine derivatives, so it’s a promising reductant to separate Np, Pu effectively,Reduction kinetic study of the reaction in nitric acid is performed by spectrophotometry. The effect of some factors such as concentration of TBH, HNO3, Np(Ⅵ) and temperature on the redox

  17. Effect of Counteranions on the Conformational Equilibrium of 1-Butyl-3-methylimidazolium-Based Ionic Liquids

    OpenAIRE

    Naohiro Hatano; Takahiro Takekiyo; Hiroshi Abe; Yukihiro Yoshimura

    2011-01-01

    We have investigated the nonspherical anion effect on the trans-trans (TT) and gauche-trans (GT) equilibrium in pure 1-butyl-3-methylimidazolium ([bmim]+)-based room temperature ionic liquids (RTILs) by the Raman spectroscopy. The intensity ratio of the [bmim]+ cation in [bmim]+-based RTILs having nonspherical anions changes with nature of the anions. However, the enthalpy change of the [bmim]+ cation is approximately −1.0 kJ/mol for all [bmim]+-based RTILs used in this study and is independe...

  18. Photo catalytic degradation of methyl tert-Butyl Ether (MTBE) from contaminated water: complete mineralization

    Energy Technology Data Exchange (ETDEWEB)

    Eslami, A.; Nasseri, S.; Maleki, A.; Aghvami, T.

    2009-07-01

    Methyl tert-butyl ether (MTBE) has been commercially used as an octane enhancer to replace tetraethyl lead in gasoline since 1979. The high mobility, water solubility, and resistance to natural attenuation associated with MTBE may result in contamination of ground and surface waters. In this investigation the degradation of aqueous MTBE at relatively high concentrations was studied by UV-vis/TiO{sub 2}/O{sub 2} photo catalytic process. The effect of important operational parameters such as ph, oxygen flow, catalyst loading, and irradiation time were also studied. (Author)

  19. TRANS-ARTERIAL EMBOLIZATION WITH N-BUTYL CYANOACRYLATE GLUE FOR RENAL BLEEDING: Case Report

    Directory of Open Access Journals (Sweden)

    Benny Young

    2014-08-01

    Full Text Available Background: The objectivity in management of renal bleeding is to preserve a significant renal parenchyma tissue and prevent associated morbidities like anemic shock or renal impairment from substantial nephron demise or obstructed uropathy. Trans-arterial embolization therapy by interventional radiology offers a high success rate with potential of reserving normal renal tissue. The selection material for renal arterial embolization largely depends on vasculature anatomy and end-point of procedure. N-butyl cyanoacrylate glue in our experience is applied in lesion supplied by small size of end-artery. 

  20. Organophosphazenes. 15. Reactions of Hexafluorocyclotriphosphazene with Tert- and n-Butyl Lithium Reagents

    Science.gov (United States)

    1981-12-04

    appears to be the preferred pathway in most organo - 43lithium reactions. The H NMR spectrum of the bis t-butyl derivative (II) shows a doublet 3with J...34 168(19.4%, N3P3FCI2+), 167 (39.5%, N3P3CH +), 149(42.7%, N3P3 CH2 ) N3P3 F 3 (t-C 4H9 ) 3 (111) 36(8.%,N CH+ 3d (2.%,N PFrU .363(87.73, N3P3F3C 1 2 12 7

  1. Crystal structure of 4-azidomethyl-6-tert-butyl-2H-chromen-2-one

    Directory of Open Access Journals (Sweden)

    Nasseem El-Khatatneh

    2015-04-01

    Full Text Available In the title compound, C14H15N3O2, one of the methyl C atoms of the tert-butyl group lies almost in the plane of the chromene ring system [deviation = −0.097 (2 Å], one lies above and one lies below [deviations = 1.460 (3 and 1.006 (3 Å, respectively]. The C—C—N—N torsion angle is 142.33 (17°. In the crystal, moelcules are linked by weak C—H...O hydrogen bonds to generate C(6 chains propagating in the [010] direction.

  2. Study of toxicity of butylated hydroxyanisole (BHA) in pregnant gilts and their foetuses.

    Science.gov (United States)

    Hansen, E V; Meyer, O; Olsen, P

    1982-01-01

    An embryotoxicity study on butylated hydroxyanisole (BHA) was carried out in SPF pigs (Danish Landrace). BHA was incorporated in the diet and administered to pigs in doses of 0, 50, 200 and 400 mg/kg body wt/day from mating (artificial insemination) to day 110 of the gestation period, when the foetuses were removed. Significant lower weight gain was observed in the dams dosed 400 mg/kg body wt/day. Absolute and relative organ weight for the liver and thyroid gland showed a dose-related increase, BHA neither affected the reproduction data nor the incidence of defects in the foetuses.

  3. Synchrotron Photoionization Investigation of the Oxidation of Ethyl tert-Butyl Ether.

    Science.gov (United States)

    Winfough, Matthew; Yao, Rong; Ng, Martin; Catani, Katherine; Meloni, Giovanni

    2017-02-23

    The oxidation of ethyl tert-butyl ether (ETBE), a widely used fuel oxygenated additive, is investigated using Cl atoms as initiators in the presence of oxygen. The reaction is carried out at 293, 550, and 700 K. Reaction products are probed by a multiplexed chemical kinetics photoionization mass spectrometer coupled with the synchrotron radiation produced at the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory. Products are identified on the basis of mass-to-charge ratio, ionization energies, and shape of photoionization spectra. Reaction pathways are proposed together with detected primary products.

  4. Degradation of a recalcitrant xenobiotic compound: methyl tert-butyl ether (MTBE) metabolism by mycobacterium austroafricanum; Degradation d'un compose xenobiotique recalcitrant: metabolisme du methyl tert-butyl ether (MTBE) par mycobacterium austroafricanum IFP 2012

    Energy Technology Data Exchange (ETDEWEB)

    Francois, A.

    2002-11-01

    Methyl tert-butyl ether (MTBE) is introduced up to 15% (vol/vol) in gasoline in order to obtain a good octane number and to prevent carbon monoxide emissions. However, as a consequence of storage tanks leakage, MTBE became one of the major pollutants of aquifers because of its very low biodegradability. The present study aimed at investigating the biodegradation of MTBE by Mycobacterium austroafricanum IFP 2012. The MTBE metabolic pathway was partially elucidated owing to the identification of some intermediates (tert-butyl formate (TBF), tert-butyl alcohol (TBA), a-hydroxy-isobutyric acid and acetone) and some enzymatic activities (MTBE/TBA monooxygenase (non hemic and inducible), TBF esterase, 2-propanol: NDMA oxidoreductase and another monooxygenase involved in acetone degradation). The involvement of TBF and the requirement of cobalt could be explanations for the low natural attenuation of MTBE; whereas the methoxy group does not seem to be implicated. (author)

  5. BINDING OF THERMO-SENSITIVE AND pH-SENSITIVE BUTYLATED POLY(ALLYLAMINE)S WITH LYSOZYME

    Institute of Scientific and Technical Information of China (English)

    Jing-jing Liu; Yun-feng Yan; Ping Yao

    2011-01-01

    Butyl modified poly(allylamine)s with butyl substitution degrees of 15% to 70% were prepared. The polymers show pH sensitive property and lower critical solution temperature (LCST) behavior. The LCST appears at lower temperature, lower pH and lower polymer concentration for the polymer with higher butylated degree. The binding of native lysozyme with the polymers depends on the hydrophobicity of the polymers at the pH range that the protein and the polymer carry the same positive charges. The increase of polymer hydrophobicity can increase the binding with lysozyme, but the self-aggregation of the polymer decreases the binding. The bound lysozyme molecules can recover their native activity completely after the dissociation of the complexes. Compared with native lysozyme, the denatured one which exposes the hydrophobic residues can increase the binding with the polymer and form stable complex nanoparticles.

  6. Alkylation of Hydroquinone with tert-Butyl Alcohol over Bis[(perfluoroalkyl)sulfonyl]imides Supported on MCM-41

    Institute of Scientific and Technical Information of China (English)

    YUAN, Yu-Bin; NIE, Jin; ZHANG, Zheng-Bo; ZHOU, San-Yi

    2006-01-01

    Bis[(perfluoroalkyl)sulfonyl]imides [HN(SO2Rf)2, and Rf represents the perfluorinated alkyl group] supported on MCM-41 were synthesized and characterized by XRD, FTIR, SEM, TGA and N2-adsorption techniques. The supported catalysts, HN(SO2Rf)2/MCM-41, were used as the catalysts for the tert-butylation of hydroquinone (HQ)with tert-butyl alcohol (TBA) in the liquid phase. A high yield (52.0%) of 2-tert-butyl hydroquinone (TBHQ) could be obtained in the presence of 5 mol% HN(SO2C4F9)2/MCM-41 under the optimized reaction conditions and the heterogeneous catalyst could be recycled at least 6 times without substantial loss of activity.

  7. Esterification of levulinic acid to n-butyl levulinate over heteropolyacid supported on acid-treated clay

    Institute of Scientific and Technical Information of China (English)

    S.Dharne; V.V.Bokade

    2011-01-01

    Levulinic acid has been identified as a promising green, biomass-derived platform chemical, n-Butyl levulinate is used as an important intermediate having diverse applications.The present work focuses on the synthesis of n-butyl levulinate by esterification of levulinic acid with n-butanol using heteropolyacid (HPA) supported on acid-treated clay montmorillonite (K10).20% (w/w) dodecatungestophosphoric acid (DTPA) supported on K10 was found to be the most efficient catalyst with 97% levulinic acid conversion and 100% selectivity towards n-butyl levulinate.Effects of various process parameters were studied to examine the efficacy of 20% (w/w) DTPA/K10 for optimization of the activity.

  8. Higher levels of ethyl paraben and butyl paraben in rat amniotic fluid than in maternal plasma after subcutaneous administration

    DEFF Research Database (Denmark)

    Frederiksen, Hanne; Taxvig, Camilla; Hass, Ulla

    2008-01-01

    Parabens are a group of antimicrobial preservatives widely used in cosmetics, pharmaceuticals, and in foods. Previous in vitro and in vivo studies have shown weak estrogenic effects of some parabens. Thus, especially, exposure of fetus and infants via the mother is a matter of concern. In order...... to obtain more knowledge about the distribution of ethyl paraben and butyl paraben in pregnant rats and pups after perinatal exposure, the presented study was designed. The data show response and distribution of ethyl paraben and butyl paraben in maternal rat plasma, pools of amniotic fluids, placenta......, whole-body fetuses, and in fetal liver after dosing of dams with 100, 200, and 400 mg/kg body weight (bw)/day from gestational day 7 to 21. After cesarean section of dams, the fluids and tissues were collected, deconjugated, and purified by solid-phase extraction, and ethyl paraben and butyl paraben...

  9. Neutral Pd (II) and Ni (II) Acetylide Complexes as Single-Component Initiators for Polymerizations of Butyl Methacrylate and Acrylates

    Institute of Scientific and Technical Information of China (English)

    SUN,Hong-Mei(孙宏枚); YANG,Mu-Jie(杨慕杰); SHEN,Qi(沈琪)

    2001-01-01

    Homogeneous polymerization of butyl methacrylate (BMA)using Pd(II)- and Ni(n)-based acetyiide complexes as singlecomponent initiators has been investigated CHCl3 at 60°C.M(PPh)2(C≡CR)2 (M = Pti,Ni; R = Ph,CH2OH,CH2OOCCH3) were found to be a novel type of effective initiators for the polymerization of butyl methacrylate.Amongthem,Pd(PPh3)2(C≡CPh)2 (PPP) shows the highest activi-ty.Besides,PPP alone can also initiate the homogeneous poly-merizations of acrylates,e.g.,methyl acrylate (MA),andn-butyl acrylate (BA).The present type of polymerization isnot hindered by the incorporation of hydroquinone.``

  10. Butyl 2-(5-iodo-3-methylsulfinyl-1-benzofuran-2-ylacetate

    Directory of Open Access Journals (Sweden)

    Uk Lee

    2009-02-01

    Full Text Available In the title compound, C15H17IO4S, the O atom and the methyl group of the methylsulfinyl substituent lie on opposite sides of the plane of the benzofuran fragment. The crystal structure is stabilized by weak intermolecular C—H...π interactions between a methyl H atom of the methylsulfinyl group and the benzene ring of the benzofuran system, and by an I...O halogen bond of 3.173 (3 Å and a nearly linear C—I...O angle of 171.7 (1°. In addition, the crystal structure exhibits weak intermolecular C—H...O hydrogen bonds. The O atom of the carbonyl group and the butyl chain are both disordered over two positions with site-occupancy factors from refinement of 0.55 (4 and 0.45 (4 (for the O atom, and 0.76 (2 and 0.24 (2 (for the butyl group.

  11. Post-discharge treatment of air effluents polluted by butyl-mercaptan: role of nitrate radical

    Science.gov (United States)

    Braci, L.; Ognier, S.; Liu, Y. N.; Cavadias, S.

    2011-01-01

    Dry air polluted by butyl-mercaptan was treated in a Dielectric Barrier Discharge (DBD) reactor at atmospheric pressure using air as plasmagene gas in discharge and post-discharge modes. The energy density was varied between 200 to 1300 J/L. To assess the treatment efficiency, the concentrations of buty-mercaptan, total Volatile Organic Compounds (VOCs) and SO2 were determined in the exhaust gas. Whatever the energy density was, the treatment efficiency was better in post-discharge mode. The butyl-mercaptan could be completely eliminated from 400 J/L and SO2 selectivity was always low, below 10%. Measurements of CO, CO2 and total VOCs indicated that 50 to 70% of the reaction products were condensed on the reactor wall in the form of micro-droplets, depending on the energy density. FTIR and XPS techniques were used to characterize the reaction products which were soluble in water. These analyses indicated that the reaction products contain oxygen, nitrogen and sulphur in an oxidized form. A reaction mechanism involving hydrogen abstraction from the -SH bond by the nitrate radical was proposed, pointing out the important role of nitrate radicals NO3 in the reactivity of air flowing post-discharge.

  12. Determination of methacrylic acid in food simulants by pyrolytic butylation-gas chromatography.

    Science.gov (United States)

    Huang, Zhongping; Qiu, Ruofeng; Liu, Tingfei; Huang, Yilei; Zhu, Zuoyi; Wang, Lili

    2016-07-08

    An on-line pyrolytic butylation approach was proposed to determine methacrylic acid (MA) in food simulants by gas chromatography (GC) without an expensive pyrolyzer. MA in food simulants was converted into butyl methacrylate in the presence of tetrabutylammonium hydroxide (TBAH) without any pretreatment at 330°C in the injection-port, contributing to high GC signal response. The derivatizing conditions for the proposed method were optimized, namely the injection-port temperature, type and amount of the organic alkaline used for derivatization. A series of standard solutions of MA in the range of 1.0-50mg/kg were analyzed with correlation coefficient r≥0.9975. The limits of detection (LODs) were less than 0.15mg/kg for MA in four matrix simulants (distilled water, 3%w/v acetic acid, 10%v/v ethanol, and isooctane). Relative standard deviations (RSDs) for retention time, peak height and peak area were all less than 3.88%. The technique was successfully applied to the analysis of MA migrating from plastic cup samples, with recoveries of added MA in the range of 96.5-123.0%. Direct injection of the simulants into the GC system after migration tests, without any pretreatment step, makes the developed method of great value for rapid screening analysis of samples in bulks.

  13. Gall stone dissolution with methyl tert-butyl ether: how to avoid complications.

    Science.gov (United States)

    Hellstern, A; Leuschner, M; Frenk, H; Dillinger, H W; Caspary, W; Leuschner, U

    1990-01-01

    Fifty of 52 patients with cholesterol gall bladder stones were treated with methyl tert-butyl ether. In 48 of 50 (96%) patients the stones dissolved after an average interval of 9.5 hours. Mean stone size was 1.7 cm (0.5-3.3 cm), mean stone number was 14.6 (1-70). Twelve patients (24%) complained of nausea, a burning sensation, or vomiting. In one patient bile leakage occurred and another suffered haematobilia (4%). The puncture set was improved, and a special basket was developed to extract stones that had escaped into the cystic duct. To prevent bile leakage or haemorrhage from the incision channel, a tissue adhesive was injected into the channel or ceruletid was administered subcutaneously before removing the catheter to induce contraction of the gall bladder. Thus we were able to treat 44 patients without any complications. Nausea and vomiting could be reduced if the treatment time was kept short and the perfusion volume was as low as possible. Methyl tert-butyl ether treatment is a successful treatment of gall bladder stones with few complications. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:2387519

  14. Electric Heating Property from Butyl Rubber-Loaded Boron Carbide Composites

    Institute of Scientific and Technical Information of China (English)

    MENG Dechuan; WANG Ninghui; LI Guofeng

    2014-01-01

    We researched the electric heating property from butyl rubber-loaded boron carbide composite. The effects of boron carbide content on bulk resistivity, voltage-current characteristic, thermal conductivity and thermal stability of boron carbide/butyl rubber (IIR) polymer composite were introduced. The analysis results indicated that the bulk resistivity decreased greatly with increasing boron carbide content, and when boron carbide content reached to 60%, the bulk resistivity achieved the minimum. Accordingly, electric heating behavior of the composite is strongly dependent on boron carbide content as well as applied voltage. The content of boron carbide was found to be effective in achieving high thermal conductivity in composite systems. The thermal conductivity of the composite material with added boron carbide was improved nearly 20 times than that of the pure IIR. The thermal stability test showed that, compared with pure IIR, the thermal stable time of composites was markedly extended, which indicated that the boron carbide can significantly improve the thermal stability of boron carbide/IIR composite.

  15. Biodegradation of Methyl tert-Butyl Ether by Co-Metabolism with a Pseudomonas sp. Strain

    Directory of Open Access Journals (Sweden)

    Shanshan Li

    2016-09-01

    Full Text Available Co-metabolic bioremediation is supposed to be an impressive and promising approach in the elimination technology of methyl tert-butyl ether (MTBE, which was found to be a common pollutant worldwide in the ground or underground water in recent years. In this paper, bacterial strain DZ13 (which can co-metabolically degrade MTBE was isolated and named as Pseudomonas sp. DZ13 based on the result of 16S rRNA gene sequencing analysis. Strain DZ13 could grow on n-alkanes (C5-C8, accompanied with the co-metabolic degradation of MTBE. Diverse n-alkanes with different carbon number showed a significant influence on the degradation rate of MTBE and accumulation of tert-butyl alcohol (TBA. When Pseudomonas sp. DZ13 co-metabolically degraded MTBE with n-pentane as the growth substrate, a higher MTBE-degrading rate (Vmax = 38.1 nmol/min/mgprotein, Ks = 6.8 mmol/L and lower TBA-accumulation was observed. In the continuous degradation experiment, the removal efficiency of MTBE by Pseudomonas sp. Strain DZ13 did not show an obvious decrease after five times of continuous addition.

  16. Structural elucidation of 4-(cystein-S-yl)butyl glucosinolate from the leaves of Eruca sativa.

    Science.gov (United States)

    Kim, Sun-Ju; Kawaharada, Chiami; Jin, Shigeki; Hashimoto, Makoto; Ishii, Gensho; Yamauchi, Hiroaki

    2007-01-01

    The structurally unique glucosinolate (GSL), 4-(cystein-S-yl)butyl GSL, was identified in the leaves of hydroponically-grown rocket salad (Eruca sativa Mill.). Its electrospray ionization mass spectrometry (ESI-MS)/MS spectrum indicated that this unusual GSL had a molecular weight of 414 as a desulfo (DS)-GSL, and a molecular formula of C(14)H(25)N(2)O(8)S(2) based on its negative ion matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS) spectrum. For further confirmation, the 4-(cystein-S-yl)butyl DS-GSL was prepared with authentic L-Ser and purified dimeric 4-mercaptobutyl DS-GSL, and its chemical structure then confirmed by ESI-MS/MS data. It is named "glucorucolamine" as a trivial name from its ammonia sensitivity. This unique GSL was found to the greatest extent when rocket salad was grown in a 100% NH4+-N nutrient solution. Despite it clearly seems to reduce the detoxification of excess NH4+ in the leaves of rocket salad, present knowledge about the unique GSL is still far from being sufficient.

  17. Effect of butyl paraben on the development and microbial composition of periphyton.

    Science.gov (United States)

    Song, Chaofeng; Lin, Juan; Huang, Xiaolong; Wu, Yonghong; Liu, Jiantong; Wu, Chenxi

    2016-03-01

    Parabens are extensively used as preservatives and bactericides in personal care and other consumer products, and are commonly found in wastewater and surface water as contaminants. However, few data are currently available on the ecotoxicity of parabens. Periphyton biofilm, a widely distributed microbial aggregate of ecological importance in aquatic environment, is frequently used for water quality monitoring, ecological restoration, and toxicity assessment. In this work, the effects of butyl paraben on the development and microbial composition of periphyton biofilm was studied in a laboratory experiment for 32 days using flow through channels. No effect was observed at the environmental relevant concentration level (0.5 μg L(-1)) during the experiment. At the highest tested concentration level (5000 μg L(-1)), following effects were noted: (1) inhibition on algae growth at the end of the experiment as indicated by the chlorophyll a and total biovolume; (2) inhibition of photosynthetic efficiency on day 24 as suggested by the maximal Photosystem II quantum yield (Fv/Fm); (3) decrease of the algal diversity on day 24 and 32 as reflected by the Pielou and Shannon-Weiner indices. Bacteria were less sensitive than algae in the periphyton biofilm, which showed no difference at all tested concentration levels as illustrated by the Biolog EcoPlates™ analysis. Therefore, we conclude that environmental residues of butyl paraben have a very low risk to periphyton in aquatic ecosystems.

  18. Production of fatty acid butyl esters using the low cost naturally immobilized Carica papaya lipase.

    Science.gov (United States)

    Su, Erzheng; Wei, Dongzhi

    2014-07-01

    In this work, the low cost naturally immobilized Carica papaya lipase (CPL) was investigated for production of fatty acid butyl esters (FABE) to fulfill the aim of reducing the lipase cost in the enzymatic butyl-biodiesel process. The CPL showed specificities to different alcohol acyl acceptors. Alcohols with more than three carbon atoms did not have negative effects on the CPL activity. The CPL catalyzed butanolysis for FABE production was systematically investigated. The reaction solvent, alcohol/oil molar ratio, enzyme amount, reaction temperature, and water activity all affected the butanolysis process. Under the optimized conditions, the highest conversion of 96% could be attained in 24 h. These optimal conditions were further applied to CPL catalyzed butanolysis of other vegetable oils. All of them showed very high conversion. The CPL packed-bed reactor was further developed, and could be operated continuously for more than 150 h. All of these results showed that the low cost Carica papaya lipase can be used as a promising lipase for biodiesel production.

  19. Method for determination of methyl tert-butyl ether in gasoline by gas chromatography.

    Science.gov (United States)

    Achten, C; Püttmann, W

    2001-03-02

    A simple method for the determination of methyl tert-butyl ether (MTBE) in gasoline has been developed. The separation of MTBE from other analytes was controlled by the use of gas chromatography-mass spectrometry in the full scan mode using the characteristic primary, secondary and tertiary ions m/z 73, 57 and 43. The sample mass spectrum did not show any superimposition of other analytes. The separation from the common gasoline component 2-methylpentane was sufficient for reliable quantitation. An application of the developed conditions using gas chromatography with flame ionization detection was performed by the analysis of regular, euro super, super premium unleaded and 'Optimax' gasoline from petrol stations in the area of Frankfurt/Main, Germany. Regular unleaded gasoline shows an average MTBE content of 0.4% (w/w), whereas the MTBE content in euro super gasoline varies between 0.4 and 4.2% (w/w). The blending of MTBE to super premium has increased from 8.2% (w/w) in 1998 to 9.8% (w/w) on average in 1999. The recently introduced gasoline 'Optimax' shows an average MTBE content of 11.9% (w/w). The presented method might also be used for the analysis of other ethers, such as ethyl tert-butyl ether, which requires the use of another internal standard.

  20. Degradation of tert-butyl formate and its intermediates by an ozone/UV process.

    Science.gov (United States)

    Garoma, Temesgen; Gurol, Mirat D; Thotakura, Lalitha; Osibodu, Olufisayo

    2008-12-01

    In this paper, the oxidation of tert-butyl formate (TBF) in aqueous solution by an ozone/UV process was described. The oxidation process was investigated experimentally in a semibatch reactor. The results of the study indicated that the ozone/UV process was very effective in oxidizing TBF. tert-Butyl alcohol (TBA), hydroxy-iso-butyraldehyde (HiBA), acetone, formaldehyde, and formic acid were identified as major primary intermediates during the oxidation of TBF. About 90% organic carbon balance was obtained indicating that most reaction intermediates have been identified and quantified. Some of the primary intermediates were also oxidized in the ozone/UV system. Accordingly, HiBA, acetone, formaldehyde, and formic acid were the primary intermediates of TBA oxidation. The oxidation of acetone in the ozone/UV system generated formaldehyde, pyruvaldehyde, acetic acid, formic acid as primary intermediates. It was also observed that the reaction intermediates formed during the oxidation of TBF react well in the ozone/UV system and complete mineralization could be achieved by the process.

  1. Ethyl tert-butyl ether (ETBE)-degrading microbial communities in enrichments from polluted environments.

    Science.gov (United States)

    Le Digabel, Yoann; Demanèche, Sandrine; Benoit, Yves; Fayolle-Guichard, Françoise; Vogel, Timothy M

    2014-08-30

    The ethyl tert-butyl ether (ETBE) degradation capacity and phylogenetic composition of five aerobic enrichment cultures with ETBE as the sole carbon and energy source were studied. In all cases, ETBE was entirely degraded to biomass and CO2. Clone libraries of the 16S rRNA gene were prepared from each enrichment. The analyses of the DNA sequences obtained showed different taxonomic compositions with a majority of Proteobacteria in three cases. The two other enrichments have different microbiota with an abundance of Acidobacteria in one case, whereas the microbiota in the second was more diverse (majority of Actinobacteria, Chlorobi and Gemmatimonadetes). Actinobacteria were detected in all five enrichments. Several bacterial strains were isolated from the enrichments and five were capable of degrading ETBE and/or tert-butyl alcohol (TBA), a degradation intermediate. The five included three Rhodococcus sp. (IFP 2040, IFP 2041, IFP 2043), one Betaproteobacteria (IFP 2047) belonging to the Rubrivivax/Leptothrix/Ideonella branch, and one Pseudonocardia sp. (IFP 2050). Quantification of these five strains and two other strains, Rhodococcus sp. IFP 2042 and Bradyrhizobium sp. IFP2049, which had been previously isolated from one of the enrichments was carried out on the different enrichments based on quantitative PCR with specific 16S rRNA gene primers and the results were consistent with the hypothesized role of Actinobacteria and Betaproteobacteria in the degradation of ETBE and the possible role of Bradyrhizobium strains in the degradation of TBA.

  2. Higher levels of ethyl paraben and butyl paraben in rat amniotic fluid than in maternal plasma after subcutaneous administration.

    Science.gov (United States)

    Frederiksen, Hanne; Taxvig, Camilla; Hass, Ulla; Vinggaard, Anne M; Nellemann, Christine

    2008-12-01

    Parabens are a group of antimicrobial preservatives widely used in cosmetics, pharmaceuticals, and in foods. Previous in vitro and in vivo studies have shown weak estrogenic effects of some parabens. Thus, especially, exposure of fetus and infants via the mother is a matter of concern. In order to obtain more knowledge about the distribution of ethyl paraben and butyl paraben in pregnant rats and pups after perinatal exposure, the presented study was designed. The data show response and distribution of ethyl paraben and butyl paraben in maternal rat plasma, pools of amniotic fluids, placenta, whole-body fetuses, and in fetal liver after dosing of dams with 100, 200, and 400 mg/kg body weight (bw)/day from gestational day 7 to 21. After cesarean section of dams, the fluids and tissues were collected, deconjugated, and purified by solid-phase extraction, and ethyl paraben and butyl paraben were analyzed by liquid chromatography-tandem mass spectrometry. Markedly higher levels of ethyl paraben compared to butyl paraben were found in all fluids and tissues. Both ethyl paraben and butyl paraben in maternal plasma, livers, and whole-body tissues from fetus seemed to be saturated after dosing with >or= 100 mg/kg bw/day, while both compounds were excreted into amniotic fluid in a dose-dependent manner. Significant difference was found between the level of ethyl paraben in maternal plasma and amniotic fluid after dosing with 200 mg/kg bw/day as well as between the levels of butyl paraben in maternal plasma and amniotic fluid after dosing with 100, 200, and 400 mg/kg bw/day.

  3. Desempenho e qualidade dos ovos de poedeiras comerciais alimentadas com rações contendo farelo de coco tratado ou não com antioxidante Performance and egg quality of laying hens fed diets containing coconut meal treated with and without antioxidant

    Directory of Open Access Journals (Sweden)

    Irani Ribeiro Vieira Lopes

    2011-11-01

    Full Text Available Este experimento foi conduzido para avaliar a estabilidade oxidativa do farelo de coco (FC tratado ou não com butil-hidroxitolueno (BHT e armazenado por 35 dias e estudar o efeito de rações contendo esse ingrediente sobre o desempenho e a qualidade do ovo de poedeiras. Um lote de 200 kg de farelo de coco foi dividido em cinco partes: uma foi armazenada sem a adição de antioxidante e as demais tratadas com 500 ppm de BHT nos dias 0, 7, 14 e 21. A estabilidade oxidativa do farelo de coco foi acompanhada por meio dos índices de acidez e de peróxidos, determinados semanalmente. Após 35 dias de armazenamento, 10% de farelo de coco tratado e não tratado com BHT nos diferentes tempos de armazenamento foi usado na formulação de rações isonutrientes para poedeiras comerciais. Foram utilizadas 180 poedeiras da linhagem Hisex White, distribuídas ao acaso em 5 tratamentos e 6 repetições de 6 aves cada. Os índices de acidez e de peróxidos do farelo de coco armazenado com ou sem BHT aumentaram com o tempo de armazenamento. Contudo, os tratamentos não afetaram o desempenho nem a qualidade dos ovos das aves. O farelo de coco armazenado por 35 dias sem antioxidante, embora sofra oxidação, pode ser usado em níveis de até 10% na ração para poedeiras comerciais.This experiment was conducted to evaluate the oxidative stability of coconut meal treated with or without butylated hydroxytoluene (BHT at different storage times and the effect of diets containing this ingredient on laying hens' performance and egg quality. A 200-kg batch of freshly produced coconut meal was divided into five equal portions. One portion was stored without BHT and the others were treated with BHT at zero, 7, 14 and 21 days. The oxidative stability of coconut meal was measured by the acidity index and peroxide index determined weekly. At the end of the 35-day storage time, this ingredient was used in the formulation of diets for laying hen. One hundred and eighty

  4. Isotope effects and the temperature dependences of the hyperfine coupling constants of muoniated sec-butyl radicals in condensed phases.

    Science.gov (United States)

    Fleming, Donald G; Bridges, Michael D; Arseneau, Donald J; Chen, Ya Kun; Wang, Yan Alexander

    2011-04-01

    Reported here is the first μSR study of the muon (A(μ)) and proton (A(p)) β-hyperfine coupling constants (Hfcc) of muoniated sec-butyl radicals, formed by muonium (Mu) addition to 1-butene and to cis- and trans-2-butene. The data are compared with in vacuo spin-unrestricted MP2 and hybrid DFT/B3YLP calculations reported in the previous paper (I), which played an important part in the interpretation of the data. The T-dependences of both the (reduced) muon, A(μ)′(T), and proton, A(p)(T), Hfcc are surprisingly well explained by a simple model, in which the calculated Hfcc from paper I at energy minima of 0 and near ±120° are thermally averaged, assuming an energy dependence given by a basic 2-fold torsional potential. Fitted torsional barriers to A(μ)′(T) from this model are similar (~3 kJ/mol) for all muoniated butyl radicals, suggesting that these are dominated by ZPE effects arising from the C−Mu bond, but for A(p)(T) exhibit wide variations depending on environment. For the cis- and trans-2-butyl radicals formed from 2-butene, A(μ)′(T) exhibits clear discontinuities at bulk butene melting points, evidence for molecular interactions enhancing these muon Hfcc in the environment of the solid state, similar to that found in earlier reports for muoniated tert-butyl. In contrast, for Mu−sec-butyl formed from 1-butene, there is no such discontinuity. The muon hfcc for the trans-2-butyl radical are seemingly very well predicted by B3LYP calculations in the solid phase, but for sec-butyl from 1-butene, showing the absence of further interactions, much better agreement is found with the MP2 calculations across the whole temperature range. Examples of large proton Hfcc near 0 K are also reported, due to eclipsed C−H bonds, in like manner to C−Mu, which then also exhibit clear discontinuities in A(p)(T) at bulk melting points. The data suggest that the good agreement found between theory and experiment from the B3LYP calculations for eclipsed bonds in

  5. Diisobutyl phthalate has comparable anti-androgenic effects to di-n-butyl phthalate in fetal rat testis

    DEFF Research Database (Denmark)

    Boberg, Julie; Petersen, Marta Axelstad; Vinggaard, Anne;

    2006-01-01

    Phthalates are widely used as plasticizers in various consumer products and building materials. Some of the phthalates are known to interfere with male reproductive development in rats, and di-n-butyl phthalate (DBP), diethylhexyl phthalate (DEHP) and butyl benzyl phthalate (BBP) were recently...... banned for use in toys in the EU mainly due to their reproductive toxicity. Diisobutyl phthalate (DiBP) has similar structural and application properties as DBP. and is being used as a substitute for DBR However, knowledge on male reproductive effects of DiBP in experimental animals is lacking, Methods...

  6. Quercetin protects human hepatoma HepG2 against oxidative stress induced by tert-butyl hydroperoxide.

    Science.gov (United States)

    Alía, Mario; Ramos, Sonia; Mateos, Raquel; Granado-Serrano, Ana Belén; Bravo, Laura; Goya, Luis

    2006-04-15

    Flavonols such as quercetin, have been reported to exhibit a wide range of biological activities related to their antioxidant capacity. The objective of the present study was to investigate the protective effect of quercetin on cell viability and redox status of cultured HepG2 cells submitted to oxidative stress induced by tert-butyl hydroperoxide. Concentrations of reduced glutathione and malondialdehyde, generation of reactive oxygen species and activity and gene expression of antioxidant enzymes were used as markers of cellular oxidative status. Pretreatment of HepG2 with 10 microM quercetin completely prevented lactate dehydrogenase leakage from the cells. Pretreatment for 2 or 20 h with all doses of quercetin (0.1-10 microM) prevented the decrease of reduced glutathione and the increase of malondialdehyde evoked by tert-butyl hydroperoxide in HepG2 cells. Reactive oxygen species generation induced by tert-butyl hydroperoxide was significantly reduced when cells were pretreated for 2 or 20 h with 10 microM and for 20 h with 5 microM quercetin. Finally, some of the quercetin treatments prevented the significant increase of glutathione peroxidase, superoxide dismutase, glutathione reductase and catalase activities induced by tert-butyl hydroperoxide. Gene expression of antioxidant enzymes was also affected by the treatment with the polyphenol. The results of the biomarkers analyzed clearly show that treatment of HepG2 cells in culture with the natural dietary antioxidant quercetin strongly protects the cells against an oxidative insult.

  7. Carbamoylcholine analogs as nicotinic acetylcholine receptor agonists--structural modifications of 3-(dimethylamino)butyl dimethylcarbamate (DMABC)

    DEFF Research Database (Denmark)

    Hansen, Camilla Petrycer; Jensen, Anders Asbjørn; Balle, Thomas;

    2009-01-01

    Compounds based on the 3-(dimethylamino)butyl dimethylcarbamate (DMABC) scaffold were synthesized and pharmacologically characterized at the alpha(4)beta(2), alpha(3)beta(4,) alpha(4)beta(4) and alpha(7) neuronal nicotinic acetylcholine receptors (nAChRs). The carbamate functionality and a small...

  8. SYNTHESIS OF METHYL TERT-BUTYL ETHER CATALYZED BY ACIDIC ION-EXCHANGE RESINS - INFLUENCE OF THE PROTON ACTIVITY

    NARCIS (Netherlands)

    PANNEMAN, HJ; BEENACKERS, AACM

    1995-01-01

    The catalytic activity of various strong acid ion-exchange resins on the synthesis of methyl tert-butyl ether (MtBE) from methanol and isobutene has been investigated. Relative to Amberlyst 15, Kastel CS 381 and Amberlyst CSP have similar rate constants, whereas Duolite ES 276 and Amberlyst XE 307 h

  9. Synthesis and characterization of di- and triorganotin(IV) complexes of 2-tert-butyl-4-methyl phenol

    Indian Academy of Sciences (India)

    Neeraj Sharma; Archana; Maridula Thakur; S S Bhatt; S C Chaudhry

    2007-07-01

    The di- and trialkyltin(IV) complexes of composition R2SnCl2-(OAr), and -Bu3Sn(OAr) (R = -Bu and Me; = 1 and 2; OAr = OC6H3Bu-2-Me-4) have been synthesized by the reactions of di-n-butyl and dimethyltin dichlorides and tri-n-butyltin(IV) chloride with 2-tert-butyl-4-methylphenol and triethylamine in tetrahydrofuran. The reaction of triphenyltin chloride with trimethylsilyl-2-t-butyl-4-methylphenoxide in the same solvent however, gives a complex of composition Ph3Sn(OAr). The complexes have been characterized by microanalyses, molar conductance measurements, molecular weight determinations and IR and 1H, 13C and 119Sn NMR and mass spectral studies. Thermal behaviour of the complexes has been studied by TGA and DTA techniques. From the non-isothermal TG data, the kinetic and thermodynamic parameters have been calculated employing Coats-Redfern equation and the mechanism of decomposition has been computed using non-isothermal kinetic method. Thermal investigations on the blends of poly(methylmethacrylate). PMMA, with organotin(IV)-2-tert-butyl-4-methylphenoxides have shown increased thermal stability compared to pure PMMA suggesting thereby their potential as additives towards PMMA.

  10. Rapid and high yields of synthesis of butyl acetate catalyzed by Novozym 435 : Reaction optimization by response surface methodology

    NARCIS (Netherlands)

    Martins, Andrea B.; Graebin, Natalia G.; Soibelmann Glock Lorenzoni, André; Fernandez-Lafuente, Roberto; Ayub, Marco A. Z.; Rodrigues, Rafael C.

    2011-01-01

    In this paper is described the optimization of the esterification reaction of butyl acetate synthesis catalyzed by Candida antarctica lipase B (Novozym 435). The reaction parameters temperature, substrate molar ratio, enzyme content, and added water, and their responses measured as conversion yields

  11. Di-iso-Butyl Phthalate MATERNAL AND FETAL DATA FROM THE LE GRAY RESEARCH TEAM FOR NCEA June 15 2016

    Science.gov (United States)

    this file contains the raw data on the effects of in utero administration of di-iso-butyl phthalate on maternal weight gain during dosing and the numbers of fetuses and fetal resorptions. The data have all been previously published, as described on the file metadata sheet.

  12. Crystal structure of 2-tert-butyl-1,3-thiazolo[4,5-b]pyridine

    Directory of Open Access Journals (Sweden)

    Gamal A. El-Hiti

    2014-09-01

    Full Text Available The title compound, C10H12N2S, does not contain any strong hydrogen-bond donors but two long C—H...N contacts are observed in the crystal structure, with the most linear interaction linking molecules along [010]. The ellipsoids of the tert-butyl group indicate large librational motion.

  13. Densities and Kinematic Viscosities for the Systems Benzene + Methyl Formate, Benzene + Ethyl Formate, Benzene + Propyl Formate, and Benzene + Butyl Formate

    DEFF Research Database (Denmark)

    Emmerling, Uwe; Rasmussen, Peter

    1998-01-01

    Densities and kinematic viscosities have been measured for the system benzene + methyl formate at 20°C and for the systems benzene + ethyl formate, benzene + propyl formate, and benzene + butyl formate from 20°C to 50°C. The results for the system benzene + methyl formate have been correlated usi...

  14. Nonlinear viscoelastic response of carbon black-filled butyl rubber and implications for o-ring aging

    Energy Technology Data Exchange (ETDEWEB)

    Adolf, D.

    1997-11-01

    Butyl rubber, unfortunately, has pronounced nonlinear viscoelastic behavior, which may be modelled by a separable KBKZ formalism. While these effects seem to have minimal impact on accelerated sealing force measurements, they do severely impact compression set tests. Therefore, a new test is suggested for evaluating field-return o-rings which is free from such confounding effects.

  15. INTERACTION OF METHYL-TERT BUTYL ETHER AND WATER STRESS ON SEED GERMINATION AND SEEDLING GROWTH IN SOIL MICROCOSMS

    Science.gov (United States)

    Methyl tert-butyl ether (MTBE) is a widespread contaminant in surface and ground water in the United States. Frequently irrigation is used to water fields to germinate planted seeds and sustain plant growth. A likely possibility exists that water used may have some MTBE. Our s...

  16. Basic butylated methacrylate copolymer/kappa-carrageenan interpolyelectrolyte complex: preparation, characterization and drug release behaviour.

    Science.gov (United States)

    Prado, H J; Matulewicz, M C; Bonelli, P; Cukierman, A L

    2008-09-01

    The formation of a novel interpolyelectrolyte complex (IPEC) between basic butylated methacrylate copolymer and kappa-carrageenan was investigated and the product formed was characterized. Turbidity measurements and elemental analyses pointed to a 1:1 interaction of the repeating units. These results and FT-IR confirmed IPEC formation. Electronic microscopy images, particle size determination by image analysis and N(2) (77K) adsorption measurements were consistent with a porous material. This IPEC formed presented very good flowability and compactibility. Two maxima were observed in the swelling behaviour as a function of pH. The performance of the IPEC as a matrix for controlled release of drugs was evaluated, using ibuprofen as a model drug. Release profiles were properly represented by a mathematical model, which indicates that the system releases ibuprofen in a zero-order manner. These profiles could be controlled by conveniently modifying the proportion of the IPEC in the tablets.

  17. Effect of Counteranions on the Conformational Equilibrium of 1-Butyl-3-methylimidazolium-Based Ionic Liquids

    Directory of Open Access Journals (Sweden)

    Naohiro Hatano

    2011-01-01

    Full Text Available We have investigated the nonspherical anion effect on the trans-trans (TT and gauche-trans (GT equilibrium in pure 1-butyl-3-methylimidazolium ([bmim]+-based room temperature ionic liquids (RTILs by the Raman spectroscopy. The intensity ratio of the [bmim]+ cation in [bmim]+-based RTILs having nonspherical anions changes with nature of the anions. However, the enthalpy change of the [bmim]+ cation is approximately −1.0 kJ/mol for all [bmim]+-based RTILs used in this study and is independent of the anionic species. The present results indicate that the conformational stability of the [bmim]+ cation in [bmim]+-based RTILs including nonspherical anions is driven by the entropic contribution associated with the orientation and configuration of the [bmim]+ cation with respect to the counteranion.

  18. Green polymer electrolytes based on chitosan and 1-butyl-3-methylimidazolium acetate

    Science.gov (United States)

    Shamsudin, Intan Juliana; Ahmad, Azizan; Hassan, Nur Hasyareeda

    2014-09-01

    Green polymer electrolytes based on chitosan as the polymer matrix and ionic liquid 1-butyl-3-methylimidazolium acetate [Bmim][OAc] as charge carriers were prepared by solution casting technique. Complexes with various amount of ionic liquid loading were investigated as possible ionic conducting polymers. The ionic conductivity was found to increase with increasing weight percent of ionic liquid. The highest ionic conductivity of the charged chitosan-[Bmim][OAc] was 2.44 × 10-3 S cm-1 at 90 wt.% of [Bmim][OAc] content at ambient temperature. Attenuated Total Reflection Fourier Transform infrared (ATR-FTIR) spectroscopy has proven the interaction between chitosan and [Bmim][OAc]. X-ray Diffraction (XRD) has shown that the amorphosity of the complexes increase as the amount of [Bmim][OAc] increase.

  19. Green polymer electrolytes based on chitosan and 1-butyl-3-methylimidazolium acetate

    Energy Technology Data Exchange (ETDEWEB)

    Shamsudin, Intan Juliana [Chemistry Department, Centre for Defence Foundation Studies, National Defence University of Malaysia, 57000 Kuala Lumpur (Malaysia); Ahmad, Azizan; Hassan, Nur Hasyareeda [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600, Bangi, Selangor Darul Ehsan (Malaysia)

    2014-09-03

    Green polymer electrolytes based on chitosan as the polymer matrix and ionic liquid 1-butyl-3-methylimidazolium acetate [Bmim][OAc] as charge carriers were prepared by solution casting technique. Complexes with various amount of ionic liquid loading were investigated as possible ionic conducting polymers. The ionic conductivity was found to increase with increasing weight percent of ionic liquid. The highest ionic conductivity of the charged chitosan-[Bmim][OAc] was 2.44 × 10{sup −3} S cm{sup −1} at 90 wt.% of [Bmim][OAc] content at ambient temperature. Attenuated Total Reflection Fourier Transform infrared (ATR-FTIR) spectroscopy has proven the interaction between chitosan and [Bmim][OAc]. X-ray Diffraction (XRD) has shown that the amorphosity of the complexes increase as the amount of [Bmim][OAc] increase.

  20. Electrochemical behavior of CoCl2 in ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate

    Institute of Scientific and Technical Information of China (English)

    ZHOU Zhou; HE De-liang; CUI Zheng-dan; ZHONG Jian-fang; LI Guo-xi

    2008-01-01

    The electrochemical behavior of CoCl2 in 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim]PF6) was investigated by cyclic voltammetry. The cyclic voltammograms were obtained from electrochemical measurement under different temperatures, and the reversible behavior for Co2+/Co3+ redox couple on glassy carbon electrode in [bmim]PF6 was confirmed by the characteristic of the peak currents. The diffusion coefficients (about 10-11m2/s) of Co2+ in [bmim]PF6 under different temperatures were evaluated from the dependence of the peak current density on the potential scan rates in cyclic voltammograms. It is found that the diffusion coefficient increases with increasing temperature. Diffusion activation energy of Co2+ in [bmim]PF6 is also calculated to be 23.4kJ/mol according to the relationship between diffusion coefficient and temperature.

  1. Study on antibacterial dental resin using tri-n-butyl(4-vinylbenzyl)phosphonium chloride.

    Science.gov (United States)

    Kurata, Shigeaki; Hamada, Nobushiro; Kanazawa, Akihiko; Endo, Takeshi

    2011-01-01

    The antibacterial properties of a polymeric phosphonium salt were studied to determine its suitability as an additive to develop an antibacterial dental resin. The phosphonium salt monomer studied was tri-n-butyl(4-vinylbenzyl)phosphonium chloride (VP), and acrylic acid (AC) and methacryloyloxyethyl trimethyl ammonium chloride (MA) were used as controls. The antibacterial activity of these monomers and their corresponding polymers (PVP, PAC, and PMA) against Streptococcus mutans (S. mutans) was examined. When incubating S. mutans in a medium containing 10 μmol/mL for 24 hours, the antibacterial activity of PVP against S. mutans was high, while the antibacterial activity of PMA and VP was lower. AC, PAC and PMA exhibited the lowest antibacterial activity. The mechanical properties of the copolymers of methyl methacrylate, 2-hydroxyethyl methacrylate, and VP decreased as VP content increased, and were lower than those of poly(methyl methacrylate).

  2. (2-tert-Butyl-3-phenyl-2,3-dihydroisoxazole-4,5-diylbis(phenylmethanone

    Directory of Open Access Journals (Sweden)

    M. R. Prathapachandra Kurup

    2013-08-01

    Full Text Available The phenyl and tert-butyl groups of the title compound, C27H25NO3, exhibit a trans configuration in agreement with the stereochemistry of the Z phenyl-N-tert-butylnitrone starting material. The attached carbonyl groups are not coplanar with the neighboring dihydroisoxazole ring and the phenyl rings they are bonded to, with torsion angles of 59.26 (8, 17.53 (11, 16.52 (12 and 52.86 (7°. The dihedral angle between the dihydroisoxazole ring and the directly attached phenyl group is 86.86 (8°. There are two nonclassical intermolecular C—H...O hydrogen-bonding interactions that operate together with an intermolecular C—H...π interaction to form a supramolecular architecture in the crystal system.

  3. Barrierity of hydrogenated butadiene-acrylonitrile rubber and butyl rubber after exposure to organic solvents.

    Science.gov (United States)

    Krzemińska, Sylwia; Rzymski, Władysław M

    2011-01-01

    Resistance of antichemical clothing primarily depends on the type of material it is made from, in particular on the type of polymer used for coating the fabric carrier. This paper reports on systematic investigations on the influence of the cross-linking density of an elastomer and the composition of a cross-linked elastomer on its resistance to permeation of selected organic solvents. Tests of barrier material samples made from nonpolar butyl rubber (IIR) and polar hydrogenated butadiene-acrylonitrile rubber (HNBR) showed that (a) in rubber-solvent systems with medium thermodynamic affinity, cross-linking density influenced resistance to permeation and (b) the polarity of the system had a significant influence on barrierity.

  4. Effect of 1-butyl-3-methylimidazolium tetrafluoroborate on the formation rate of CO2 hydrate

    Institute of Scientific and Technical Information of China (English)

    Qi Chen; Yong Yu; Peng Zeng; Wei Yang; Qianqing Liang; Xiaoming Peng; Yansheng Liu; Yufeng Hu

    2008-01-01

    The effect of the addition of 1-butyl-3-methylimidazolium tetrafluoroborate([C4mim][BF4])on the formation rates of CO2 hydrates was investigate.The isothermal and isobaric methods were used to measure the formation rates of CO2 hydrates.As compared to those of pure water,the data of phase equilibrium changed greatly.The effects of pressure,temperature,and the concentration of [C4mim][BF4] aqueous solution on the formation rates of CO2 hydrates were investigated.With a constant concentration of[C4mim][BF4],the rate of gas consumption was enhanced with the lowering of experimental temperature.However,a decrease in pressure exerted an opposite effect on the rate of gas consumption.Moreover,the addition of[C4mim][BF4]raised the equilibrium pressure of hydrate formation at the same temperature.

  5. Analysis of Oxygenated Component (butyl Ether) and Egr Effect on a Diesel Engine

    Science.gov (United States)

    Choi, Seung-Hun; Oh, Young-Taig

    Potential possibility of the butyl ether (BE, oxygenates of di-ether group) was analyzed as an additives for a naturally aspirated direct injection diesel engine fuel. Engine performance and exhaust emission characteristics were analyzed by applying the commercial diesel fuel and oxygenates additives blended diesel fuels. Smoke emission decreased approximately 26% by applying the blended fuel (diesel fuel 80 vol-% + BE 20vol-%) at the engine speed of 25,000 rpm and with full engine load compared to the diesel fuel. There was none significant difference between the blended fuel and the diesel fuel on the power, torque, and brake specific energy consumption rate of the diesel engine. But, NOx emission from the blended fuel was higher than the commercial diesel fuel. As a counter plan, the EGR method was employed to reduce the NOx. Simultaneous reduction of the smoke and the NOx emission from the diesel engine was achieved by applying the BE blended fuel and the cooled EGR method.

  6. Butyl rubber O-ring seals: Revision of test procedures for stockpile materials

    Energy Technology Data Exchange (ETDEWEB)

    Domeier, L.A.; Wagter, K.R.

    1996-12-01

    Extensive testing showed little correlation between test slab and O-ring performance. New procedures, comparable to those used with the traditional test slabs, were defined for hardness, compression set, and tensile property testing on sacrificial O-ring specimens. Changes in target performance values were made as needed and were, in one case, tightened to reflect the O-ring performance data. An additional study was carried out on O-ring and slab performance vs cure cycle and showed little sensitivity of material performance to large changes in curing time. Aging and spectra of certain materials indicated that two sets of test slabs from current vendor were accidently made from EPDM rather than butyl rubber. Random testing found no O-rings made from EPDM. As a result, and additional spectroscope test will be added to the product acceptance procedures to verify the type of rubber compound used.

  7. Liquid-Liquid equilibria of the water-acetic acid-butyl acetate system

    Directory of Open Access Journals (Sweden)

    E. Ince

    2002-04-01

    Full Text Available Experimental liquid-liquid equilibria of the water-acetic acid-butyl acetate system were studied at temperatures of 298.15± 0.20, 303.15± 0.20 and 308.15± 0.20 K. Complete phase diagrams were obtained by determining solubility and tie-line data. The reliability of the experimental tie-line data was ascertained by using the Othmer and Tobias correlation. The UNIFAC group contribution method was used to predict the observed ternary liquid-liquid equilibrium (LLE data. It was found that UNIFAC group interaction parameters used for LLE did not provide a good prediction. Distribution coefficients and separation factors were evaluated for the immiscibility region.

  8. Microencapsulation of butyl stearate as a phase change material by interfacial polycondensation in a polyurea system

    Energy Technology Data Exchange (ETDEWEB)

    Chen Liang [College of Material Science and Engineering, Nanjing University of Technology, Nanjing 210009 (China)], E-mail: doseng_1982@hotmail.com; Xu Lingling; Shang Hongbo; Zhang Zhibin [College of Material Science and Engineering, Nanjing University of Technology, Nanjing 210009 (China)

    2009-03-15

    For the last 20 years, microencapsulated phase change materials (MicroPCMs), which combine microencapsulation technology and phase change material, have been attracted more and more interest. By overcoming some limitations of the PCMs, the MicroPCMs improve the efficiency of PCMs and make it possible to apply PCMs in many areas. In this experiment, polyurea microcapsules containing phase change materials were prepared using interfacial polycondensation method. Toluene-2,4-diisocyanate (TDI) and ethylenediamine (EDA) were chosen as monomers. Butyl stearate was employed as a core material. The MicroPCMs' properties have been characterized by dry weight analysis, differential scanning calorimetry, Fourier transform IR spectra analysis and optical microscopy. The results show that the MicroPCMs were synthesized successfully and that, the phase change temperature was about 29 deg. C, the latent heat of fusion was about 80 J g{sup -1}, the particle diameter was 20-35 {mu}m.

  9. Microencapsulation of butyl stearate as a phase change material by interfacial polycondensation in a polyurea system

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Chen; Lingling, Xu; Hongbo, Shang; Zhibin, Zhang [College of Material Science and Engineering, Nanjing University of Technology, Nanjing 210009 (China)

    2009-03-15

    For the last 20 years, microencapsulated phase change materials (MicroPCMs), which combine microencapsulation technology and phase change material, have been attracted more and more interest. By overcoming some limitations of the PCMs, the MicroPCMs improve the efficiency of PCMs and make it possible to apply PCMs in many areas. In this experiment, polyurea microcapsules containing phase change materials were prepared using interfacial polycondensation method. Toluene-2,4-diisocyanate (TDI) and ethylenediamine (EDA) were chosen as monomers. Butyl stearate was employed as a core material. The MicroPCMs' properties have been characterized by dry weight analysis, differential scanning calorimetry, Fourier transform IR spectra analysis and optical microscopy. The results show that the MicroPCMs were synthesized successfully and that, the phase change temperature was about 29 C, the latent heat of fusion was about 80 J g{sup -1}, the particle diameter was 20-35 {mu}m. (author)

  10. Transdermal uptake of diethyl phthalate and di(n-butyl) phthalate directly from air: Experimental verification

    DEFF Research Database (Denmark)

    Weschler, Charles J.; Bekö, Gabriel; Koch, Holger M.;

    2015-01-01

    Background: Fundamental considerations indicate that, for certain phthalate esters, dermal absorption from air is an uptake pathway that is comparable to or greater than inhalation. Yet this pathway has not been experimentally evaluated and has been largely overlooked when assessing uptake...... of phthalate esters. Objectives: This study investigated transdermal uptake, directly from air, of diethyl phthalate (DEP) and di(n-butyl) phthalate (DnBP) in humans. Methods: In a series of experiments, six human participants were exposed for 6 hr in a chamber containing deliberately elevated air...... concentrations of DEP and DnBP. The participants either wore a hood and breathed air with phthalate concentrations substantially below those in the chamber or did not wear a hood and breathed chamber air. All urinations were collected from initiation of exposure until 54 hr later. Metabolites of DEP and Dn...

  11. Study of n-Butyl Acrylate Self-Initiation Reaction Experimentally and via Macroscopic Mechanistic Modeling

    Directory of Open Access Journals (Sweden)

    Ahmad Arabi Shamsabadi

    2016-04-01

    Full Text Available This paper presents an experimental study of the self-initiation reaction of n-butyl acrylate (n-BA in free-radical polymerization. For the first time, the frequency factor and activation energy of the monomer self-initiation reaction are estimated from measurements of n-BA conversion in free-radical homo-polymerization initiated only by the monomer. The estimation was carried out using a macroscopic mechanistic mathematical model of the reactor. In addition to already-known reactions that contribute to the polymerization, the model considers a n-BA self-initiation reaction mechanism that is based on our previous electronic-level first-principles theoretical study of the self-initiation reaction. Reaction rate equations are derived using the method of moments. The reaction-rate parameter estimates obtained from conversion measurements agree well with estimates obtained via our purely-theoretical quantum chemical calculations.

  12. Inhibition Effect of 1-Butyl-4-Methylpyridinium Tetrafluoroborate on the Corrosion of Copper in Phosphate Solutions

    Directory of Open Access Journals (Sweden)

    M. Scendo

    2011-01-01

    Full Text Available The influence of the concentration of 1-Butyl-4-methylpyridinium tetrafluoroborate (4MBPBF4 as ionic liquid (IL on the corrosion of copper in 0.5 M PO43− solutions of pH 2 and 4 was studied. The research involved electrochemical polarization method, and scanning electron microscopy (SEM technique. The results obtained showed that the inhibition efficiency of corrosion of copper increases with an increase in the concentration of 4MBPBF4 but decreases with increasing temperature. The thermodynamic functions of corrosion analysis and adsorptive behavior of 4MBPBF4 were carried out. During the test, the adsorption of the inhibitor on the copper surface in the phosphate solutions was found to obey the Langmuir adsorption isotherm and had a physical mechanism.

  13. Linear Viscoelasticity of Spherical SiO 2 Nanoparticle-Tethered Poly(butyl acrylate) Hybrids

    KAUST Repository

    Goel, Vivek

    2010-12-01

    The melt state linear viscoelastic properties of spherical silica nanoparticles with grafted poly(n-butyl acrylate) chains of varying molecular weight were probed using linear small amplitude dynamic oscillatory measurements and complementary linear stress relaxation measurements. While the pure silica-tethered-polymer hybrids with no added homopolymer exhibit solid-like response, addition of matched molecular weight free matrix homopolymer chains to this hybrid, at low concentrations of added homopolymer, maintains the solid-like response with a lowered modulus that can be factored into a silica concentration dependence and a molecular weight dependence. While the silica concentration dependence of the modulus is strong, the dependence on molecular weight is weak. On the other hand, increasing the amount of added homopolymer changes the viscoelastic response to that of a liquid with a relaxation time that scales exponentially with hybrid concentration. © 2010 American Chemical Society.

  14. Tribological performance and chemistry of films for di-n-butyl dithiocarbamate derivatives in rapeseed oil

    Institute of Scientific and Technical Information of China (English)

    WU Hua; ZENG XiangQiong; LU LingBo; REN TianHui

    2007-01-01

    Two di-n-butyl dithiocarbamate derivatives were easily synthesized. Their tribological performances as lubricating oil additives in rapeseed oil were evaluated using a four-ball machine, and their chemistry of films was analyzed with X-ray absorption near-edge spectroscopy (XANES). The results indicate that the two compounds possess excellent anti-wear property and good load-carrying capacity. According to the XANES results, for the thermal films, the outer surfaces are mainly composed of N, S-containing polymer and ferric sulfate, and the near-surface and the bulk are composed of ferrous sulfate, while for the anti-wear films, the outer surfaces are only composed of ferric sulfate, but the near-surface and the bulk are mainly composed of ferrous sulfate.

  15. Monomer reactivity ratios for fluoroacrylate and butyl methacrylate in miniemulsion copolymerizations initiated by potassium persulphate

    Institute of Scientific and Technical Information of China (English)

    Qing Hua Zhang; Zhen Huan Luo; Xiao Li Zhan; Feng Qiu Chen

    2009-01-01

    Miniemulsion copolymerization of butyl mathacrylate(BMA)with fluoroacrylate(HFMA,TFMA)was carded out at 70℃ by employing potassium persulphate(KPS)as initiator.Copolymer compositions at low conversion levels were determined by 1H NMR spectra techniques.The reactivity ratios were evaluated by employing Kellen-Tudos(K-T)methods,which yields the apparent reactivity ratios,rBMA=0.74,rHFMA=0.87 and rBMA=0.73,rTFMA=0.75,respectively,and Q-and e-values of HFMA and TFMA were calculated by the Alfrey-Price method.The results show that HFMA and TFMA are more active than BMA,and the cross-propagation rate constant is greater than the self-propagation one in these two copolymerizations.

  16. Poly[tetra-butyl-tetra-kis-(μ(2)-hydrogen phenyl-phospho-nato)ditin(IV)].

    Science.gov (United States)

    Sarr, Modou; Diasse-Sarr, Aminata; Diop, Libasse; Molloy, Kieran C; Kociok-Kohn, Gabriele

    2012-11-01

    In the title compound, [Sn(2)(C(4)H(9))(4)(C(6)H(6)PO(3))(4)](n), the basic unit is a dimer containing two symmetry-related Sn(IV) atoms bridged by two hydrogenphenylphosphonate anions. This fragment is located about an inversion center, and each Sn(IV) atom is linked to two other hydrogenphenylphosphonate anions, giving a layered structure parallel to (010). The coordination geometry for the Sn(IV) atoms is close to octa-hedral. The layers are connected via O-H⋯O hydrogen bonds, generating a three-dimensional network. One butyl group is disordered over two sets of sites, with occupancies of 0.49 (2) and 0.51 (2).

  17. Isolation and Initial Characterization of A Pure Cultures Capable to Degradation Methyl tert- Butyl Ether (MTBE

    Directory of Open Access Journals (Sweden)

    A Nikpey

    2006-07-01

    Full Text Available Methyl tert-butyl ether (MTBE, a gasoline octane enhancer, was introduced as a substitute for lead tetraethyl over 30 years ago. Widespread use of MTBE in gasoline, has introduced MTBE into the environment compartments, mostly into the under ground and surface water and water as a second most frequently detected contaminant. In this study, we have isolated pure cultures from bacterial consortium capable to use MTBE as a sole carbon and energy source. MTBE biodegradation rate was measured in headspace by gas chromatography. Initial liner rates of biodegradation by Pinpoint and white strains were found 2.9 mg and 3 mg MTBE hˉ1 gˉ1 wet biomass, respectively. The results of 16S rDNA PCR disclosed similarities in the banding patterns between the cultures, and the known degrading strain PM1. The results of this study suggest promising perspectives for engineering the in situ bioremediation of MTBE.

  18. Structure-activity relationships for insect growth regulators derived from substituted di-tert-butyl phenols

    Energy Technology Data Exchange (ETDEWEB)

    Walton, B.T.; Sanborn, J.R.; Metcalf, R.L.

    1979-01-01

    Thirty-six para-substituted derivatives of 2,6-di-tert-butyl phenols were synthesized and tested for toxicity to fourth instar larvae of the mosquito Culex quinquefasciatus Say. Toxicities of these compounds ranged from an LC/sub 50/ of 0.004 ppM to LC/sub 50/ > 10 ppM. Mosquitoes treated with toxic analogues characteristically died shortly after the pupal molt and appeared to be morphologically normal, untanned pupae. Correlations of insecticidal activity with physicochemical parameters of the para-substituent was found to explain 71.82% of the variation in insecticidal activity expressed as log LC/sub 50/(mM).

  19. Degradation of aqueous methyl tert-butyl ether by photochemical, biological, and their combined processes

    Directory of Open Access Journals (Sweden)

    Azadeh Asadi

    2006-01-01

    Full Text Available The degradation of aqueous methyl tert-butyl ether (MTBE at relatively high concentrations was investigated by various photo-induced oxidation processes such as UV/H2O2 and UV/TiO2 as well as biological processes and their combination. It was shown that the degradation of MTBE by UV/H2O2 and TiO2 photocatalytic followed a first-order model with apparent rate constant of 1.31×10−1 and 1.21×10−2 min-1, respectively. It was observed that UV/H2O2/TiO2 process did not have any advantages over each of the other processes alone. The biodegradation of methyl tert-butyl ether (MTBE was evaluated using aerobic mixed culture with three different approaches, including ultimate biological oxygen demand (BODU assessment, nonacclimated, and acclimated mixed cultures. The apparent rate constant for the biodegradation of MTBE by nonacclimated mixed culture was 4.36×10−2 day-1. It was shown that the acclimatization of the mixed cultures enhanced the rate of biodegradation of MTBE to 3.24×10−1mg L-1h-1. Finally, the effects of the photocatalytic pretreatment of aqueous MTBE on its subsequent biological treatment were studied. It was observed that the rate of bioreaction was not enhanced and the photocatalytic pretreatment had adverse effects on its biological treatment so that the apparent rate constant decreased to 2.83×10−1 mg L-1h-1.

  20. Modeling the temperature dependence of N-methylpyrrolidone permeation through butyl- and natural-rubber gloves.

    Science.gov (United States)

    Zellers, E T; Sulewski, R

    1993-09-01

    This paper describes the temperature dependence of N-methylpyrrolidone (NMP) permeation through gloves used in microelectronics fabrication facilities. One type of butyl-rubber glove (North B161), two types of natural-rubber gloves (Edmont Puretek and Ansell Pacific White), and a natural rubber/nitrile/neoprene-blend glove (Pioneer Trionic) were tested at four temperatures from 25-50 degrees C using the ASTM F739-85 permeation test method. The butyl-rubber glove showed no breakthrough after four hours of exposure at any temperature. The variations with temperature of measured breakthrough times (BT) and steady-state permeation rates (SSPR) for the other gloves were described well by Arrhenius relationships, with BT values decreasing by factors of 7-10 and SSPR values increasing by factors of 4-6 over the temperature range studied. Extrapolation to 70 and 93 degrees C, the temperatures at which degreasing is often performed, yielded BT values of rubber glove, following an initial exposure at 25 degrees C and air drying overnight, low levels of NMP vapor were detected off-gassing from the inner surfaces of the gloves. Experimental results were then compared to those expected from several permeation models. Estimates of the equilibrium solvent solubility, S, were calculated using a model based on three-dimensional solubility parameters. Estimates of the solvent diffusion coefficient, D, were obtained from correlations with either the solvent kinematic viscosity or the product of the Flory interaction parameter, chi, and the solvent molar volume. Combining these values of D and S in Fickian diffusion equations gave modeled BT estimates that were within 23% of experimental values over the temperature range examined. Modeled SSPR values were within 50% (typically within 25%) of experimental values. Another model based on a generalized Arrhenius relationship also provided useful but generally less accurate estimates of the changes in BT and SSPR values with temperature.

  1. The mechanism of catalytic methylation of 2-phenylpyridine using di-tert-butyl peroxide.

    Science.gov (United States)

    Sharma, Akhilesh K; Roy, Dipankar; Sunoj, Raghavan B

    2014-07-14

    The mechanism of palladium chloride-catalyzed direct methylation of arenes with peroxides is elucidated by using the energetics computed at the M06 density functional theory. The introduction of a methyl group by tert-butyl peroxides at the ortho-position of a prototypical 2-phenyl pyridine, a commonly used substrate in directed C-H functionalization reactions, is examined in detail by identifying the key intermediates and transition states involved in the reaction sequence. Different possibilities that differ in terms of the site of catalyst coordination with the substrate and the ensuing mechanism are presented. The important mechanistic events involved are (a) an oxidative or a homolytic cleavage of the peroxide O-O bond, (b) C-H bond activation, (c) C-C bond activation, and (d) reductive elimination involving methyl transfer to the aromatic ring. We have examined both radical and non-radical pathways. In the non-radical pathway, the lowest energy pathway involves C-H bond activation prior to the coordination of the peroxide to palladium, which is subsequently followed by the O-O bond cleavage of the peroxide and the C-C bond activation. Reductive elimination in the resulting intermediate leads to the vital C-C bond formation between methyl and aryl carbon atoms. In the non-radical pathway, the C-C bond activation is higher in energy and has been identified as the rate-limiting step of this reaction. In the radical pathway, however, the activation barrier for the C-C bond cleavage is lower than for the peroxide O-O bond cleavage. A combination of a radical pathway up to the formation of a palladium methyl intermediate and a subsequent non-radical pathway has been identified as the most favored pathway for the title reaction. The predicted mechanism is in good agreement with the experimental observations on PdCl2 catalyzed methylation of 2-phenyl pyridine using tert-butyl peroxide.

  2. Ethyl t-butyl ether: review of reproductive and developmental toxicity.

    Science.gov (United States)

    de Peyster, Ann

    2010-06-01

    Ethyl t-butyl ether (ETBE) is a motor fuel oxygenate used in reformulated gasoline. Knowledge of developmental and reproductive toxicity potential of ETBE is critical for making informed decisions about acceptance and regulations. This review discusses toxicology studies providing information about effects on reproduction and the conceptus. Seven GLP-compliant studies following widely accepted protocols have focused specifically on developmental and reproductive toxicity (DART) in rats and rabbits exposed to ETBE by gavage with doses up to 1,000 mg/kg body weight/day, the limit specified in standardized test guidelines. Other repeat-dose general toxicology studies have administered ETBE to rodents for up to 180 days, and included reproductive organ weights, histology, or other indications of reproductive system structure or function. DART potential of the main ETBE metabolite t-butyl alcohol and class-related MTBE has also been studied. More GLP-compliant studies exist for evaluating ETBE using well-established, currently recommended protocols than are available for many other chemicals used today. The database for determining ETBE DART potential is adequate, although not all study details are currently easily accessible for peer-review. ETBE does not appear to be selectively toxic to reproduction or embryofetal development in the absence of other manifestations of general toxicity. Studies using recommended methods for sample preservation and analysis have shown no targeted effect on the reproductive system. No embryofetal effects were observed in rabbits. Early postnatal rat pup deaths show no clear dose-response and have largely been attributed to total litter losses with accompanying evidence of maternal neglect or frank maternal morbidity.

  3. Subchronic exposure to ethyl tertiary butyl ether resulting in genetic damage in Aldh2 knockout mice.

    Science.gov (United States)

    Weng, Zuquan; Suda, Megumi; Ohtani, Katsumi; Mei, Nan; Kawamoto, Toshihiro; Nakajima, Tamie; Wang, Rui-Sheng

    2013-09-15

    Ethyl tertiary butyl ether (ETBE) is biofuel additive recently used in Japan and some other countries. Limited evidence shows that ETBE has low toxicity. Acetaldehyde (AA), however, as one primary metabolite of ETBE, is clearly genotoxic and has been considered to be a potential carcinogen. The aim of this study was to evaluate the effects of ALDH2 gene on ETBE-induced genotoxicity and metabolism of its metabolites after inhalation exposure to ETBE. A group of wild-type (WT) and Aldh2 knockout (KO) C57BL/6 mice were exposed to 500ppm ETBE for 1-6h, and the blood concentrations of ETBE metabolites, including AA, tert-butyl alcohol and 2-methyl-1,2-propanediol, were measured. Another group of mice of WT and KO were exposed to 0, 500, 1750, or 5000ppm ETBE for 6h/day with 5 days per weeks for 13 weeks. Genotoxic effects of ETBE in these mice were measured by the alkaline comet assay, 8-hydroxyguanine DNA-glycosylase modified comet assay and micronucleus test. With short-term exposure to ETBE, the blood concentrations of all the three metabolites in KO mice were significantly higher than the corresponding concentrations of those in WT mice of both sexes. After subchronic exposure to ETBE, there was significant increase in DNA damage in a dose-dependent manner in KO male mice, while only 5000ppm exposure significantly increased DNA damage in male WT mice. Overall, there was a significant sex difference in genetic damage in both genetic types of mice. These results showed that ALDH2 is involved in the detoxification of ETBE and lack of enzyme activity may greatly increase the sensitivity to the genotoxic effects of ETBE, and male mice were more sensitive than females.

  4. Combined prenatal and postnatal butyl paraben exposure produces autism-like symptoms in offspring: comparison with valproic acid autistic model.

    Science.gov (United States)

    Ali, Elham H A; Elgoly, Amany H Mahmoud

    2013-10-01

    The aim of this work is to evaluate the impact of butyl paraben (BP) in brain of the pups developed for mothers administered BP from early pregnancy till weaning and its effect on studying the behavior, brain neurotransmitters and brain derived neurotrophic factor BDNF via comparing the results with valproic acid (VA) autistic-rat model preparing by a single oral injection dose of VA (800 mg/kg b.wt) at the 12.5 days of gestation. Butyl paraben was orally and subcutaneously administered (200 mg/kg b.wt) to pregnant rats from gestation day 1 to lactation day 21. The offspring male rats were subjected at the last 3 days of lactation to Morris water maze and three chamber sociability test then decapitated and the brain was excised and dissected to the cortex, hippocampus, cerebellum, midbrain and pons for the determination of norepinephrine, dopamine and serotonin (NE, DA and 5-HT) and cortex amino acids and whole brain BDNF. The results showed similar social and learning and memory behavioral deficits in VA rat model and the butyl paraben offspring in comparison with the controls. Also, some similar alterations were observed in monoamine content, amino acids and BDNF factor in the autistic-like model and butyl paraben offspring in comparison with the controls. The alterations were recorded notably in hippocampus and pons NE, midbrain DA, hippocampus and midbrain 5-HT, and frontal cortex GABA and asparagine. These data suggest that prenatal exposure to butyl paraben induced neuro-developmental disorders similar to some of the neurodevelopmental disorders observed in the VA model of autism.

  5. Consumer's evaluation of the effects of gamma irradiation and natural antioxidants on general acceptance of frozen beef burger

    Science.gov (United States)

    Trindade, R. A.; Lima, A.; Andrade-Wartha, E. R.; Oliveira e Silva, A. M.; Mancini-Filho, J.; Villavicencio, A. L. C. H.

    2009-04-01

    The effect of addition of rosemary and oregano extracts on the sensory quality of irradiated beef burger was investigated. Batches of beef burgers were prepared with 400 ppm of rosemary or oregano extract and a group prepared with 200 ppm of synthetic butyl-hydroxytoluene (BHT)/butyl-hydroxy-anisol (BHA) was used as a control. Half of each formulation was irradiated at the maximum dose allowed for frozen meat (7 kGy). Samples were kept under frozen conditions (-20 °C) during the whole storage period, including during irradiation. Two analyses were performed after 20 and 90 days to verify the influence of the addition of the different types of antioxidants and the effect of irradiation and storage time on the acceptance of the product. Thirty-three and thirty-four untrained panelists were invited to participate in the first and second test, respectively. A structured hedonic scale ranging from 1 to 9 points was used in both analyses. BHT/BHA formulation obtained the highest score (6.73) and regarding the natural antioxidants, oregano received better acceptance (6.36). Irradiated samples formulated with oregano received a lower score, 6.03 in the first test and 5.06 in the second one, compared to the non-irradiated sample (6.36 and 5.79). In the second test (90 days), the sample formulated with BHT/BHA and which was irradiated received a higher score (6.59) when compared to the non-irradiated one (5.85). In both tests, the irradiated samples formulated with rosemary extract obtained a better score compared to the non-irradiated one, the scores being 5.00-3.82 and 5.00-3.76 in the first and second test, respectively. Our results allowed us to conclude that the natural antioxidants, rosemary and oregano extracts, present a good alternative for replacing synthetic additives in food industries, and that the irradiation process, in some cases, may help to enhance the sensory quality of food.

  6. Synthesis, X-Ray Crystal Structures, Biological Evaluation, and Molecular Docking Studies of a Series of Barbiturate Derivatives

    Directory of Open Access Journals (Sweden)

    Assem Barakat

    2016-01-01

    Full Text Available A series of barbiturates derivatives synthesized and screened for different set of bioassays are described. The molecular structures of compounds 5a, 5d, and 5f were solved by single-crystal X-ray diffraction techniques. The results of bioassay show that compounds 4a, 4b, 4c, 4d, 4e, 4f, and 4g are potent antioxidants in comparison to the tested standards, butylated hydroxytoluene (BHT, and N-acetylcysteine. Compounds 4a–4e (IC50=101.8±0.8–124.4±4.4 μM and 4g (IC50=104.1±1.9 μM were more potent antioxidants than the standard (BHT, IC50=128.8±2.1 μM. The enzyme inhibition potential of these compounds was also evaluated, in vitro, against thymidine phosphorylase, α-glucosidase, and β-glucuronidase enzymes. Compounds 4c, 4h, 4o, 4p, 4q, 5f, and 5m were found to be potent α-glucosidase inhibitors and showed more activity than the standard drug acarbose, whereas compounds 4v, and 5h were found to be potent thymidine phosphorylase inhibitors, more active than the standard drug, 7-deazaxanthine. All barbiturates derivatives (4a–4x, 4z, and 5a–5m were found to be noncytotoxic against human prostate (PC-3, Henrietta Lacks cervical (HeLa and Michigan Cancer Foundation-7 breast (MCF-7 cancer cell lines, and 3T3 normal fibroblast cell line, except 4y which was cytotoxic against all the cell lines.

  7. Modeling pulmonary fibrosis by abnormal expression of telomerase/apoptosis/collagen V in experimental usual interstitial pneumonia

    Energy Technology Data Exchange (ETDEWEB)

    Parra, E.R.; Pincelli, M.S. [Departamento de Patologia, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil); Teodoro, W.R.; Velosa, A.P.P. [Disciplina de Reumatologia, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil); Martins, V.; Rangel, M.P.; Barbas-Filho, J.V.; Capelozzi, V.L. [Departamento de Patologia, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil)

    2014-06-04

    Limitations on tissue proliferation capacity determined by telomerase/apoptosis balance have been implicated in pathogenesis of idiopathic pulmonary fibrosis. In addition, collagen V shows promise as an inductor of apoptosis. We evaluated the quantitative relationship between the telomerase/apoptosis index, collagen V synthesis, and epithelial/fibroblast replication in mice exposed to butylated hydroxytoluene (BHT) at high oxygen concentration. Two groups of mice were analyzed: 20 mice received BHT, and 10 control mice received corn oil. Telomerase expression, apoptosis, collagen I, III, and V fibers, and hydroxyproline were evaluated by immunohistochemistry, in situ detection of apoptosis, electron microscopy, immunofluorescence, and histomorphometry. Electron microscopy confirmed the presence of increased alveolar epithelial cells type 1 (AEC1) in apoptosis. Immunostaining showed increased nuclear expression of telomerase in AEC type 2 (AEC2) between normal and chronic scarring areas of usual interstitial pneumonia (UIP). Control lungs and normal areas from UIP lungs showed weak green birefringence of type I and III collagens in the alveolar wall and type V collagen in the basement membrane of alveolar capillaries. The increase in collagen V was greater than collagens I and III in scarring areas of UIP. A significant direct association was found between collagen V and AEC2 apoptosis. We concluded that telomerase, collagen V fiber density, and apoptosis evaluation in experimental UIP offers the potential to control reepithelization of alveolar septa and fibroblast proliferation. Strategies aimed at preventing high rates of collagen V synthesis, or local responses to high rates of cell apoptosis, may have a significant impact in pulmonary fibrosis.

  8. Up-regulation of heme oxygenase-1 contributes to the amelioration of aluminum-induced oxidative stress in Medicago sativa.

    Science.gov (United States)

    Cui, Weiti; Zhang, Jing; Xuan, Wei; Xie, Yanjie

    2013-10-15

    In this report, pharmacological, histochemical and molecular approaches were used to investigate the effect of heme oxygenase-1 (HO-1) up-regulation on the alleviation of aluminum (Al)-induced oxidative stress in Medicago sativa. Exposure of alfalfa to AlCl3 (0-100 μM) resulted in a dose-dependent inhibition of root elongation as well as the enhancement of thiobarbituric acid reactive substances (TBARS) content. 1 and 10 μM (in particular) Al(3+) increased alfalfa HO-1 transcript or its protein level, and HO activity in comparison with the decreased changes in 100 μM Al-treated samples. After recuperation, however, TBARS levels in 1 and 10 μM Al-treated alfalfa roots returned to control values, which were accompanied with the higher levels of HO activity. Subsequently, exogenous CO, a byproduct of HO-1, could substitute for the cytoprotective effects of the up-regulation of HO-1 in alfalfa plants upon Al stress, which was confirmed by the alleviation of TBARS and Al accumulation, as well as the histochemical analysis of lipid peroxidation and loss of plasma membrane integrity. Theses results indicated that endogenous CO generated via heme degradation by HO-1 could contribute in a critical manner to its protective effects. Additionally, the pretreatments of butylated hydroxytoluene (BHT) and hemin, an inducer of HO-1, exhibited the similar cytoprotective roles in the alleviation of oxidative stress, both of which were impaired by the potent inhibitor of HO-1, zinc protoporphyrin IX (ZnPP). However, the Al-induced inhibition of root elongation was not influenced by CO, BHT and hemin, respectively. Together, the present results showed up-regulation of HO-1 expression could act as a mechanism of cell protection against oxidative stress induced by Al treatment.

  9. Effect of antioxidant and optimal antimicrobial mixtures of carvacrol, grape seed extract and chitosan on different spoilage microorganisms and their application as coatings on different food matrices

    Directory of Open Access Journals (Sweden)

    Javiera F. Rubilar

    2013-04-01

    Full Text Available There is growing interest in the use of natural agents with antimicrobial (AM and antioxidant (AOX properties. Optimization of the AM capacity for mixtures containing carvacrol, grape seed extract (GSE and chitosan, against gram-negative (Pseudomonas aeruginosa, gram-positive bacteria (Staphylococcus aureus, Listeria innocua and Enterococcus faecalis and yeast (Saccharomyces cerevisiae at 106 cfu mL-1 was studied. To observe the synergistic or antagonistic effect and find optimal combinations between the three agents, a simplex centroid mixture design was run for each microorganism, combining carvacrol (0-300 ppm, X1, GSE (0-2000 ppm, X2 and chitosan (0-2% w/v, X3. Results of the response surface analysis showed several synergistic effects for all microorganisms. Combinations of 60 ppm-400 ppm-1.2% w/v (carvacrol-GSE-chitosan; optimal AM combination 1, OAMC-1; 9.6 ppm-684 ppm-1.25% w/v (OAMC-2; 90 ppm-160 ppm-1.24% w/v (OAMC-3 were found to be the optimal mixtures for all microorganisms. Radical scavenging activity (RSA of the same agents was then compared with a standard AOX (butylated hydroxytoluene; BHT at different concentrations (25, 50 and 100 ppm; as well as the optimal AM concentrations by the 1,1-diphenyl-2-picrylhydrazyl (DPPH method. RSA increased in the following order: chitosan< carvacrol< BHT< GSE and for the OAMC: OAMC-2< OAMC-1< OAMC-3. The best RSA (OAMC-3 was applied as a coating in two different food matrices (strawberries and salmon. For strawberries, P. aeruginosa was more sensitive to the action of OAMC-3 than S. cerevisiae. For salmon, S. aureus was more resistant to the action of OAMC-3 than E. faecalis and L. innocua.

  10. Antioxidant Activity of Flavonoids Isolated From the Fruits of Xylopia parviflora (A. Rich. Benth

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    AT Tchinda

    2014-10-01

    Full Text Available The present study evaluates the antioxidant activity of the different flavonoids of the fruits of Xylopia parviflora used in Cameroon as spice in common traditional dishes. The fruits were successively extracted with hexane and methanol. The isolation of flavonoids was guided by the DPPH-TLC technique. The methanol crude extract and isolated compounds were screened for antioxidant and free radical scavenging activities using DPPH radical-scavenging, β-carotene/linoleic acid and ferric reducing antioxidant power (FRAP assays. The total phenolic content of the methanol crude extract was determined by Folin–Ciocalteu method. The DPPH-TLC technique led to the isolation of (+-catechin (1, kaempferol 3-O-arabinofuranoside (2 and quercetin 3-O-arabinofuranoside (3 identified by NMR and mass spectra analysis. In the colorimetric DPPH test, compound 1 had the same activity (EC50 8.1µg/ml as butylated hydroxytoluene (BHT used as standard while compound 3 and the methanol crude extract were less active (EC50 17.2µg/ml. Compound 2 was completely inactive. The total phenolic content of the fruit extracts was 113.03 mg gallic acid equivalents per g of extract. In the carotene bleaching test at the highest concentration of 100µg/mL, the order of inhibition of β-carotene discoloration was BHT > crude extract > quercetin 3-O-arabinofuranoside (3 > catechin (1 > kaempferol 3-O- arabinofuranoside (2. In the reducing power assay, compound 3 was more active at concentrations 40-100µg/mL. The HPLC analysis of the methanol crude extract revealed the presence of compounds 1-3 and unidentified phenolic compounds. The antioxidant activity of the methanol extract is probably due to the presence of compounds 1 and 3.

  11. Phytochemical screening, free radical scavenging, antioxidant activity and phenolic content of Dodonaea viscosa

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    Riaz Tauheeda

    2012-01-01

    Full Text Available The purpose of this study was to evaluate the antioxidant potential of Dodonaea viscosa Jacq. Methanolic extract of the plant was dissolved in distilled water and partitioned with n-hexane, chloroform, ethyl acetate and nbutanol sequentially. Phytochemical screening showed presence of phenolics, flavonoides and cardiac glycosides in large amount in chloroform, ethyl acetate and n-butanol fraction. The antioxidant potential of all these fractions and remaining aqueous fraction was evaluated by four methods: 1,1-Diphenyl-2-picrylhydrazyl (DPPH free radical scavenging activity, total antioxidant activity, Ferric Reducing Antioxidant Power (FRAP assay and ferric thiocyanate assay along with determination of their total phenolics. The results revealed that ethyl acetate soluble fraction exhibited highest percent inhibition of DPPH radical as compared to other fractions. It showed 81.14 ± 1.38% inhibition of DPPH radical at a concentration of 60 μg/ml. The IC50 of this fraction was found to be 33.95 ± 0.58 μg/ml, relative to butylated hydroxytoluene (BHT, having IC50 of 12.54 ± 0.89 μg/mL. It also showed highest FRAP value (380.53 ± 0.74 μM of trolox equivalents as well as highest total phenolic contents (208.58 ± 1.83 GAE μg/g and highest value of inhibition of lipid peroxidation (58.11 ± 1.49% at concentration of 500 μg/ml as compared to the other studied fractions. The chloroform fraction showed highest total antioxidant activity i.e.1.078 ± 0.59 (eq. to BHT.

  12. Obtention of gelatin biopolymers by ionizing radiation; Obtencao de biopolimeros de gelatina por radiacao ionizante

    Energy Technology Data Exchange (ETDEWEB)

    Takinami, Patricia Yoko Inamura

    2014-07-01

    The gelatin (Gel) is a biocompatible and biodegradable biopolymer, which naturally forms semi-solid colloids or hydrogels in aqueous solutions. As a hydrophilic polymer, the Gel has structural and physico-mechanical properties that distinguish it from synthetic hydrophilic polymers. The study of these properties led to the development of the present work. Thus, Gel-based films and hydrogels were developed using ionizing radiation technology by different techniques: irradiation with {sup 60}Co, electron beam (EB) and/or pulsed EB. The Gel based-films enriched with different additives, such as glycerol (GLY), polyvinyl alcohol (PVA), butylated hydroxytoluene (BHT), acrylamide and/or vegetal fiber, were irradiated with doses from 10 to 60 kGy, depending on the additive; some parameters like mechanical properties, color, and water absorption were analyzed. In the radio-induced synthesis of GEL nanohydrogels, polyethylene glycol (PEG) and the mixture (MIX) of additives, PEG and GEL, the size, molar mass and surface morphology of the nanohydrogels were analyzed. There was a significant increase of gel fraction with increase of the radiation dose for the GEL/fiber samples. The GEL based-films with 10% PVA irradiated at 20 kGy showed the highest puncture strength. The addition of antioxidant BHT affected on some GEL based-films properties on applied conditions. Regarding the nanohydrogels, there was a decrease of hydrodynamic radius of MIX irradiated with {sup 60}Co from 68 ± 25 nm (2 kGy) to 35 ± 4 nm (5 kGy). The radiation proved to be a convenient tool in the modification of polymeric materials for both, GEL films and hydrogels. (author)

  13. Epithelial nuclear factor-κB signaling promotes lung carcinogenesis via recruitment of regulatory T lymphocytes.

    Science.gov (United States)

    Zaynagetdinov, R; Stathopoulos, G T; Sherrill, T P; Cheng, D-S; McLoed, A G; Ausborn, J A; Polosukhin, V V; Connelly, L; Zhou, W; Fingleton, B; Peebles, R S; Prince, L S; Yull, F E; Blackwell, T S

    2012-06-28

    The mechanisms by which chronic inflammatory lung diseases, particularly chronic obstructive pulmonary disease, confer enhanced risk for lung cancer are not well-defined. To investigate whether nuclear factor (NF)-κB, a key mediator of immune and inflammatory responses, provides an interface between persistent lung inflammation and carcinogenesis, we utilized tetracycline-inducible transgenic mice expressing constitutively active IκB kinase β in airway epithelium (IKTA (IKKβ trans-activated) mice). Intraperitoneal injection of ethyl carbamate (urethane), or 3-methylcholanthrene (MCA) and butylated hydroxytoluene (BHT) was used to induce lung tumorigenesis. Doxycycline-treated IKTA mice developed chronic airway inflammation and markedly increased numbers of lung tumors in response to urethane, even when transgene expression (and therefore epithelial NF-κB activation) was begun after exposure to carcinogen. Studies using a separate tumor initiator/promoter model (MCA+BHT) indicated that NF-κB functions as an independent tumor promoter. Enhanced tumor formation in IKTA mice was preceded by increased proliferation and reduced apoptosis of alveolar epithelium, resulting in increased formation of premalignant lesions. Investigation of inflammatory cells in lungs of IKTA mice revealed a substantial increase in macrophages and lymphocytes, including functional CD4+/CD25+/FoxP3+ regulatory T lymphocytes (Tregs). Importantly, Treg depletion using repetitive injections of anti-CD25 antibodies limited excessive tumor formation in IKTA mice. At 6 weeks following urethane injection, antibody-mediated Treg depletion in IKTA mice reduced the number of premalignant lesions in the lungs in association with an increase in CD8 lymphocytes. Thus, persistent NF-κB signaling in airway epithelium facilitates carcinogenesis by sculpting the immune/inflammatory environment in the lungs.

  14. Separation and preparation of 6-gingerol from molecular distillation residue of Yunnan ginger rhizomes by high-speed counter-current chromatography and the antioxidant activity of ginger oils in vitro.

    Science.gov (United States)

    Gan, Zhilin; Liang, Zheng; Chen, Xiaosong; Wen, Xin; Wang, Yuxiao; Li, Mo; Ni, Yuanying

    2016-02-01

    Molecular distillation residue (MD-R) from ginger had the most total phenol content of 247.6mg gallic acid equivalents per gram (GAE/g) among the ginger oils. High-speed counter-current chromatography (HSCCC) technique in semi-preparative scale was successfully performed in separation and purification of 6-gingerol from MD-R by using a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (10:2:5:7, v/v/v/v). The target compound was isolated, collected, purified by HSCCC in the head-tail mode, and then analyzed by HPLC. A total of 90.38±0.53mg 6-gingerol was obtained from 600mg MD-R, with purity of 99.6%. In addition, the structural identification of 6-gingerol was performed by EI/MS, (1)H NMR and (13)C NMR. Moreover, the orders of antioxidant activity were vitamin E (VE)>supercritical fluid extraction oleoresin (SFE-O)=MD-R=6-gingerol>molecular distillation essential oil (MD-EO) and butylated hydroxytoluene (BHT)=VE>6-gingerol>MD-R=SFE-O>MD-EO, respectively in 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) scavenging and β-Carotene bleaching.

  15. DPPH Radical Scavenging Activity and Total Phenolics of Phellinus Mushroom Extracts Collected from Northeast of Thailand

    Institute of Scientific and Technical Information of China (English)

    Prapairat Seephonkai; Sorasak Samchai; Apidech Thongsom; Suriya Sunaart; Boonkirt Kiemsanmuang; Kamonchanok Chakuton

    2011-01-01

    AIM:To investigate the antioxidant activity and total phenolic content from the crude extracts and crude fractions of ten species of Phellinus mushrooms collected from northeast Thailand.METHODS:The samples were tested for their radical scavenging activity toward 2,2-diphenyl-1-pricylhydrazyl (DPPH) radical (DPPH method) and total phenolic content (Folin-Ciocalteu method).RESULTS:Some of the investigated extracts exhibited potent radical scavenging activity with the IC5o ranging from (7.30 ±0.34) to (19.80 ± 0.13) μg.mL-1.IC50 were in the range of the standard antioxidant used; quercetin,ascorbic acid and butylated hydroxytoluene (BHT).The strongest scavenging activity as comparable to quercetin was found in the crude 80% EtOH extract of P.torulosus.The crude EtOAc fraction of P.pini showed the highest total phenolic content with a value of 87.76 ± 1.00 equivalent gallic acid (EGA) while the samples with potent antioxidant activity were also determined to have high amount of total phenolics (78.34 ±0.27 to 51.01 ± 0.38) EGA.CONCLUSION:These results indicated that crude extracts from Phellinus mushrooms have a potential to be natural antioxidant source.

  16. Isoorientin-6"-O-glucoside, a water-soluble antioxidant isolated from Gentiana arisanensis.

    Science.gov (United States)

    Ko, F N; Chu, C C; Lin, C N; Chang, C C; Teng, C M

    1998-01-15

    The antioxidant activities of isoorientin-6"-O-glucoside were studied using various models. Isoorientin-6"-O-glucoside was more potent than Trolox, probucol and butylated hydroxytoluene (BHT) in reducing the stable free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH). It also scavenged superoxide anion, peroxyl and hydroxyl radicals that were generated by xanthine/xanthine oxidase, 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH) and Fe3+-ascorbate-EDTA-H2O2 system, respectively. The IC50 value, stoichiometry factor and second-order rate constant were 9.0+/-0.8 microM, 1.8+/-0.1 and 2.6 X 10(10) M(-1) s(-1) for superoxide generation, peroxyl and hydroxyl radicals. However, isoorientin-6"-O-glucoside did not inhibit xanthine oxidase activity or scavenge hydrogen peroxide (H2O2), carbon radical or 2,2'-azobis(2,4-dimethyl-valeronitrile) (AMVN)-derived peroxyl radical in hexane. Isoorientin-6"-O-glucoside inhibited Cu2+-induced oxidation of human low-density lipoprotein (LDL) as measured by fluorescence intensity, thiobarbituric acid-reactive substance formation and electrophoretic mobility. Since isoorientin-6"-O-glucoside did not possess pro-oxidant activity, it may be an effective water-soluble antioxidant that can prevent LDL against oxidation.

  17. Analgesic and Antioxidant Activities of Algerian Retama raetam (Forssk. Webb & Berthel Extracts

    Directory of Open Access Journals (Sweden)

    Samah Djeddi

    2013-05-01

    Full Text Available Part of this work deals with t he isolation and structure elucidation of the main polar secondary metabolites of the aerial parts of Retama raetam (Forssk. Webb & Berthel, as well as the evaluation of their potential analgesic properties , while the rest deals with the antioxidant activities of the aqueous extracts of roots, stem, fruits and flowers of the plant . It was found that the isoflavones g enistein 1, 6-hydroxygenistein 2, 3'-O-methylorobol 3, pratensein 4, biochanin A 8, the flavones 6-hydroxyapigenin 7 and luteolin 5, the flavonol kaempferol 6,as well as the phenolic compound p-coumaric acid 9 reduce significantly the pain at a concentration dose of 1 mg/kg. The most active compounds were 3 and 8 (86.19% and 75.23%, respectively. The obtained aqueous extracts of R. raetam were also evaluated for their antioxidant activities using two different photometric methods; the results revealed that all extracts exerted very low free radical scavenging activity compared to the well-known butylated hydroxytoluene (BHT and lower hydrogen peroxide blocking activity than positive control gallic acid.

  18. IN VITRO ANTIOXIDANT ACTIVITIES OF LEAVES, FRUITS AND PEEL EXTRACTS OF CITRUS

    Directory of Open Access Journals (Sweden)

    Muthiah PL

    2012-03-01

    Full Text Available ABSTRACT: Aim: The present study was aimed at investigating the antioxidant activities of the leaves, fruits and peel extracts of Citrus aurantium, Citrus limetta and Citrus limon belonging to the family Rutaceae. Materials and Methods: The antioxidant activities of the hydroethanolic extracts have been evaluated by using different in vitro assays and the results were compared with the standard antioxidants such as butylated hydroxytoluene (BHT, ascorbic acid, curcumin, quercetin, etc. In addition, total phenolic and flavonoid contents in these extracts were determined as pyrocatechol and quercetin equivalents respectively. Among the extracts assayed, 4 extracts (leaf and peel extracts of C.aurantium , peel and fruit extracts of C.limetta had effective H donor ability, reducing power ability, metal chelating activity, superoxide anion radical, nitric oxide radical and hydroxyl radical scavenging activities. The antioxidant activity depends upon concentration and increased with increasing amount of the extracts. The free radical scavenging and antioxidant activities may be attributed to the presence of phenolic and flavonoid compounds present in the extracts. Result: The results obtained in the present study indicate that the leaves, fruits and peel of Citrus aurantium, Citrus limetta and Citrus limon serve as the potential source of natural antioxidants. Keywords: Antioxidant; Citrus aurantium; Citrus limetta; Citrus limon; free radical; Rutaceae.

  19. Radical-Scavenging Activity and Ferric Reducing Ability of Juniperus thurifera (L.), J. oxycedrus (L.), J. phoenicea (L.) and Tetraclinis articulata (L.).

    Science.gov (United States)

    El Jemli, Meryem; Kamal, Rabie; Marmouzi, Ilias; Zerrouki, Asmae; Cherrah, Yahia; Alaoui, Katim

    2016-01-01

    Objective. The aim of this work is to study and compare the antioxidant properties and phenolic contents of aqueous leaf extracts of Juniperus thurifera, Juniperus oxycedrus, Juniperus Phoenicea, and Tetraclinis articulata from Morocco. Methods. Antioxidant activities of the extracts were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical-scavenging ability, Trolox equivalent antioxidant capacity (TEAC), and ferric reducing antioxidant power (FRAP) assays. Also the total phenolic and flavonoids contents of the extracts were determined spectrophotometrically. Results. All the extracts showed interesting antioxidant activities compared to the standard antioxidants (butylated hydroxytoluene (BHT), quercetin, and Trolox). The aqueous extract of Juniperus oxycedrus showed the highest antioxidant activity as measured by DPPH, TEAC, and FRAP assays with IC50 values of 17.91 ± 0.37 μg/mL, 19.80 ± 0.55 μg/mL, and 24.23 ± 0.07 μg/mL, respectively. The strong correlation observed between antioxidant capacities and their total phenolic contents indicated that phenolic compounds were a major contributor to antioxidant properties of these plants extracts. Conclusion. These results suggest that the aqueous extracts of Juniperus thurifera, Juniperus oxycedrus, Juniperus phoenicea, and Tetraclinis articulata can constitute a promising new source of natural compounds with antioxidants ability.

  20. Radical-Scavenging Activity and Ferric Reducing Ability of Juniperus thurifera (L., J. oxycedrus (L., J. phoenicea (L. and Tetraclinis articulata (L.

    Directory of Open Access Journals (Sweden)

    Meryem El Jemli

    2016-01-01

    Full Text Available Objective. The aim of this work is to study and compare the antioxidant properties and phenolic contents of aqueous leaf extracts of Juniperus thurifera, Juniperus oxycedrus, Juniperus Phoenicea, and Tetraclinis articulata from Morocco. Methods. Antioxidant activities of the extracts were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH free radical-scavenging ability, Trolox equivalent antioxidant capacity (TEAC, and ferric reducing antioxidant power (FRAP assays. Also the total phenolic and flavonoids contents of the extracts were determined spectrophotometrically. Results. All the extracts showed interesting antioxidant activities compared to the standard antioxidants (butylated hydroxytoluene (BHT, quercetin, and Trolox. The aqueous extract of Juniperus oxycedrus showed the highest antioxidant activity as measured by DPPH, TEAC, and FRAP assays with IC50 values of 17.91±0.37 μg/mL, 19.80±0.55 μg/mL, and 24.23±0.07 μg/mL, respectively. The strong correlation observed between antioxidant capacities and their total phenolic contents indicated that phenolic compounds were a major contributor to antioxidant properties of these plants extracts. Conclusion. These results suggest that the aqueous extracts of Juniperus thurifera, Juniperus oxycedrus, Juniperus phoenicea, and Tetraclinis articulata can constitute a promising new source of natural compounds with antioxidants ability.

  1. Phenolic profile in Dunaliella tertiolecta growing under copper stress

    Science.gov (United States)

    López, Aroa; Rico, Milagros; Magdalena Santana-Casiano, J.; González-Dávila, Melchor; González, Aridane G.

    2014-05-01

    The present study investigates the phenolic profile of exudates and extracts of the green alga Dunaliella tertiolecta harvested in natural seawater (control) and in natural seawater in the presence of Cu(II) (315 nmol L-1 and 790 nmol L-1). Determining how polyphenol concentrations change in response to high metal levels will demonstrate the role of polyphenols in microalgae and might be useful to help explaining the dynamics of this important class of compounds in seawater. The use of reversed phase high performance liquid chromatography (RP-HPLC) allowed the identification of 14 phenolic constituents. The different experimental conditions changed the concentrations and types of polyphenols as a function of the concentration of the metal added. D. tertiolecta excretes almost twice the polyphenol concentration in the 790 nmol L-1 copper enrichment experiment, respect to the reference culture (without metal additions), in order to ameliorate the toxicity of the copper in the solution, acting as a protective mechanism. The in vitro antioxidant activity determined by using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay revealed that the extract of cells from the control exhibited higher radical scavenging activity (14 ± 0.5%) than the synthetic compound butylated hydroxytoluene (BHT) (5 ± 0.1%), commonly used in the food industry as preservative. The concentration of polyphenols within the cell encourage further studies aimed at using algae as a source of chemical principles to be considered in the health, food and pharmaceutical industry.

  2. Antioxidant Activities of Aqueous Extract from Cultivated Fruit-bodies of Cordyceps militaris (L.) Link In Vitro

    Institute of Scientific and Technical Information of China (English)

    Yu Zhan; Cai-Hong Dong; Yi-Jian Yao

    2006-01-01

    Biological antioxidants extracted from plants and fungi have potential abilities to scavenge free radicals and inhibit lipid peroxidation, playing important roles in preventing diseases, for example, cancer, and aging induced by reactive oxygen species, which may cause oxidative damage to DNA, proteins and other macromolecules. The antioxidant potency of cultivated fruit-bodies of Cordyceps militaris (L.) Link was investigated in this study. Five established in vitro systems were employed, including the 1,1-diphenyl-2-picryldrazyl (DPPH) free radical scavenging, hydroxyl radical eliminating, iron chelating, inhibition of linoleic acid lipid peroxidation and reducing power. The aqueous extract from cultivated fruit-bodies was subjected to the test of amino acid, polysaccharide and mannitol. Ascorbic acid (Vc), butylated hydroxytoluene (BHT)and ethylenediaminetetraacetic acid (EDTA) were used as positive controls for comparisons. Among the assays, the aqueous extract of C. militaris fruit-bodies shows a significant scavenging effect on DPPH,eliminating the capability on hydroxyl radicals and the chelating effect on ferrous iron. The extract also shows positive results of inhibiting linoleic acid lipid peroxidation and reducing power.

  3. Biogenic synthesis of silver nanoparticles and their antioxidant and antibacterial activity

    Science.gov (United States)

    Bhakya, S.; Muthukrishnan, S.; Sukumaran, M.; Muthukumar, M.

    2016-06-01

    Nanomedicine utilizes biocompatible nanomaterials for diagnostic and therapeutic purposes. The present study reports the use of Helicteres isora root extract for the synthesis of silver nanoparticles (AgNPs). The synthesized AgNPs were initially noticed through visual color change from yellow to reddish brown and further confirmed by surface plasmonic resonance (SPR) band at 450 nm using UV-visible spectroscopy. Morphology and size of AgNPs were determined by transmission electron microscopy (TEM) analysis. X-ray diffraction (XRD) study revealed crystalline nature of AgNPs. The prolonged stability of AgNPs was due to capping of oxidized polyphenols and carboxyl protein which was established by Fourier transform infrared spectroscopy (FTIR) study. In addition, the synthesized AgNPs were tested for antioxidant and antibacterial activities. It showed good antioxidant activity as compared to butylated hydroxytoluene (BHT) and ascorbic acid as standard antioxidant. It could be concluded that H. isora root extract can be used efficiently in the production of potential antioxidant and antibacterial AgNPs for commercial application.

  4. Separation of tocopherols by nano-liquid chromatography.

    Science.gov (United States)

    Fanali, Salvatore; Camera, Emanuela; Chankvetadze, Bezhan; D'Orazio, Giovanni; Quaglia, Maria Giovanna

    2004-04-16

    Nanoliquid chromatography (nano-LC) was used for the separation of tocopherols (delta-, gamma-, alpha-TOH), alpha-tocopherol acetate (alpha-TOH-Ac) and an antioxidant compound, namely butylated hydroxytoluene (BHT) used to prevent TOHs autoxidation. The separation was carried out in a fused silica capillary of 100 microm I.D. and 375 microm O.D. packed in our laboratory with RP18 silica stationary phase of either 5- or 3-microm diameter (23-cm long). The mobile phase was composed by mixtures of methanol (MeOH), acetonitrile (MeCN) and water. Typical analyses time for the separation of all the five components of the mixture were 6-9 min depending on the composition of the mobile phase. Efficiency and resolution were strongly influenced by the particle diameter and the highest Rs and N/m values were observed using 3-microm RP18 particles. Experiments performed with capillaries packed with 3-microm RP18 particles provided good limit of detection (LOD) and limit of quantification (LOQ) (for delta-, gamma-TOH, alpha-TOH-Ac were 4 and 8 microg/ml, while for alpha-TOH were 6 and 10 microg/ml, respectively). The optimized method was applied to extracts of serum and pharmaceutical preparation containing alpha-TOH and alpha-TOH-Ac.

  5. ISOLASI DAN KARAKTERISASI MELANOIDIN KECAP MANIS DAN PERANANNYA SEBAGAI ANTIOKSIDAN [Isolation and characterization of soy sauce melanoidin and its role as antioxidant

    Directory of Open Access Journals (Sweden)

    Dedin FR1

    2006-12-01

    Full Text Available Controlling oxidation in natural and processed foods is a difficult aspect of food preservation, even in low-fat foods. Lipid oxidation not only produces characteristic undesirable odors and flavor, but also decreases the nutritional quality and safety of foods by formation of secondary reaction products during cooking and processing. Protection of foods against lipid oxidation usually involves exclusion of oxygen by packing in vacuum or inert gases and/or the addition of antioxidants. The Maillard reaction is complex reaction. A variety of by products, intermediates and brown pigmens (melanoidins are produced, which may contribute to the flavor, antioxidative activity and color of food. The oxidative browning of soy sauce is considered to have a different mechanism from those of ascorbic acid, polyphenols and furfural, because the amount of these compounds in soy sauce is very small. Maillard reaction products of soy sauce were fractionated into high and low molecular weight compounds by ultrafiltration. Oxidative stability was evaluated in refined soybean oil containing compounds in soy sauce and butylated hydroxytoluene (BHT. Oils were oxidized at 110 oC and determined by the rancimat method and TBA value. The high molecular compounds (MW ≥100 kDa of soy sauce was found to be more inhibitory on the oxidation of soybean oil with protective index 2.43. Characteristic UV-Vis absorption was 360 – 406 nm and IR spectra indicated –OH...O groups of β-diketon or combinated C=R=R groups.

  6. Antioxidant and α-amylase inhibition activities of phenolic compounds in the extracts of Indian honey

    Institute of Scientific and Technical Information of China (English)

    Subashini Devarajan; Subhashree Venugopal

    2012-01-01

    AIM:To evaluate the antioxidant and α-amylase inhibition potential of phenolic compounds in the extracts of Indian honey.METHODS:Phenolic compounds were extracted from Indian honey through column chromatography.The antioxidant potential of extracted phenolic compounds was measured by two different biochemical assays:ferric reducing antioxidant power (FRAP)assay and scavenging activity on 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals.Moreover,α-amylase inhibition assay of phenolic compounds of honey was also evaluated.RESULTS:The scavenging inhibition rate varied from 86.8% to 78.6% from the highest (6mg·mL-1) to the lowest (1.5 mg·mL-1) concentration,whereas,reducing power assay varied from 0.89 Abs to 0.19 Abs from the highest to the lowest concentration.Butylated hydroxytoluene (BHT) was used as reference compound for antioxidant assays.α-amylase inhibition assay is reported from the phenolic honey extracts for the first time.The inhibition rate for α-amylase varied from 88.8% to 30.5% from the highest (20 μg·mL-1) to the lowest concentration (4.μg·mL-1).CONCLUSION:Honey phenolic extract possessed antioxidant and α-amylase inhibition activity,thus increasing its potential therapeutic property.

  7. Chemical Composition and Antioxidant Properties of Juniper Berry (Juniperus communis L.) Essential Oil. Action of the Essential Oil on the Antioxidant Protection of Saccharomyces cerevisiae Model Organism

    Science.gov (United States)

    Höferl, Martina; Stoilova, Ivanka; Schmidt, Erich; Wanner, Jürgen; Jirovetz, Leopold; Trifonova, Dora; Krastev, Lutsian; Krastanov, Albert

    2014-01-01

    The essential oil of juniper berries (Juniperus communis L., Cupressaceae) is traditionally used for medicinal and flavoring purposes. As elucidated by gas chromatography/flame ionization detector (GC/FID) and gas chromatography/mass spectrometry (GC/MS methods), the juniper berry oil from Bulgaria is largely comprised of monoterpene hydrocarbons such as α-pinene (51.4%), myrcene (8.3%), sabinene (5.8%), limonene (5.1%) and β-pinene (5.0%). The antioxidant capacity of the essential oil was evaluated in vitro by 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging, 2,2-azino-bis-3-ethylbenzothiazoline-6 sulfonic acid (ABTS) radical cation scavenging, hydroxyl radical (ОН•) scavenging and chelating capacity, superoxide radical (•O2−) scavenging and xanthine oxidase inhibitory effects, hydrogen peroxide scavenging. The antioxidant activity of the oil attributable to electron transfer made juniper berry essential oil a strong antioxidant, whereas the antioxidant activity attributable to hydrogen atom transfer was lower. Lipid peroxidation inhibition by the essential oil in both stages, i.e., hydroperoxide formation and malondialdehyde formation, was less efficient than the inhibition by butylated hydroxytoluene (BHT). In vivo studies confirmed these effects of the oil which created the possibility of blocking the oxidation processes in yeast cells by increasing activity of the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx). PMID:26784665

  8. Effect of Addition of Natural Antioxidants on the Shelf-Life of “Chorizo”, a Spanish Dry-Cured Sausage

    Directory of Open Access Journals (Sweden)

    Mirian Pateiro

    2015-01-01

    Full Text Available The dose effect of the addition of natural antioxidants (tea, chestnut, grape seed and beer extracts on physicochemical, microbiological changes and on oxidative stability of dry-cured “chorizo”, as well as their effect during the storage under vacuum conditions was evaluated. Color parameters were significantly (p < 0.05 affected by the addition of antioxidants so that samples that contained antioxidants were more effective in maintaining color. The improving effects were dose-dependent with highest values with the dose of 50 mg/kg during ripening and depend on the extract during vacuum packaging. Addition of antioxidants decreased (p < 0.05 the oxidation, showing thiobarbituric acid reactive substances (TBARS values below 0.4 mg MDA/kg. Natural antioxidants matched or even improved the results obtained for butylated hydroxytoluene (BHT. Regarding texture profile analysis (TPA analysis, hardness values significantly (p < 0.001 decreased with the addition of antioxidants, obtaining the lower results with the dose of 200 mg/kg both during ripening and vacuum packaging. Antioxidants reduced the counts of total viable counts (TVC, lactic acid bacteria (LAB, mold and yeast. Free fatty acid content during ripening and under vacuum conditions showed a gradual and significant (p < 0.05 release as a result of lipolysis. At the end of ripening, the addition of GRA1000 protected chorizos from oxidative degradation.

  9. Photo-oxidative damage to isolated rat liver mitochondria induced by phenothiazines

    Directory of Open Access Journals (Sweden)

    T. RODRIGUES

    2009-01-01

    Full Text Available

    Photosensitization is a well-known side-effect of phenothiazines that could involve photochemically promoted oxidative damage to mitochondria, leading to the impairment of metabolic functions and apoptosis. In this work, for the first time, we investigated the effects of photoexcited thioridazine (TR, trifluoperazine (TFP and fluphenazine (FP on isolated rat liver mitochondria. Under UV irradiation, the presence of these phenothiazines led to a dose-dependent lack of the respiratory control ratio. These effects were not accompanied by significant swelling and oxidation of protein thiol groups but were accompanied by lipid peroxidation. Lycopene and sorbate, well-known quenchers of singlet oxygen and triplet species, respectively, were ineffective at protecting mitochondrial lipids against the damage promoted by the excited phenothiazines, suggesting that photochemically-produced cation radicals were the prooxidant species. Corroborating this proposal, butylated hydroxytoluene (BHT completely inhibited the lipid peroxidation induced by UV irradiation in the presence of phenothiazines. These novel results make a significant contribution to the understanding of the photochemical properties of phenothiazines in biological systems. Keywords: Trifluoperazine, thioridazine, fluphenazine, rat liver mitochondria, oxidative stress, photochemistry, photodamage, respiratory chain.

  10. Antioxidant capacity and phenolic compounds of Lonicerae macranthoides by HPLC-DAD-QTOF-MS/MS.

    Science.gov (United States)

    Hu, Xin; Chen, Lin; Shi, Shuyun; Cai, Ping; Liang, Xuejuan; Zhang, Shuihan

    2016-05-30

    Lonicerae macranthoides with strong antioxidant activity is commonly used in traditional Chinese medicine and folk tea/beverage. However, detailed information about its antioxidant activity and bioactive compounds is limited. Then at first, we comparatively evaluated total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activities of water extract, petroleum ether, ethyl acetate and n-butanol fractions of L. macranthoides. Ethyl acetate fraction exhibited the highest level of TPC (207.38 mg GAE/g DW), TFC (53.06 mg RE/g DW) and the best DPPH scavenge activity and reducing power. n-Butanol fraction showed the best ABTS(+) and O2(-) scavenging activities. Interestingly, water extract, ethyl acetate and n-butanol fractions showed stronger antioxidant activities than positive control, butylated hydroxytoluene (BHT). After that, thirty-one antioxidant phenolic compounds, including twenty-two phenolic acids and nine flavonoids, were screened by DPPH-HPLC experiment and then identified using HPLC-DAD-QTOF-MS/MS. It is noted that twenty-one compounds (1, 3-4, 6-17, 19, 23, 26, 28-29, and 31), as far as was known, were discovered from L. macranthoide for the first time, and eleven of them (3-4, 10-17, and 23) were reported in Lonicera species for the first time. Results indicated that L. macranthoides could serve as promising source of rich antioxidants in foods, beverages and medicines for health promotion.

  11. IN VITRO ANTIOXIDANT, TOTAL PHENOLIC CONTENT AND BRINE SHRIMP LETHALITY STUDIES OF SYNEDRELLA NODIFLORA

    Directory of Open Access Journals (Sweden)

    Md. Hassan Kawsar et al.

    2012-05-01

    Full Text Available The antioxidant activity of methanol extract of whole plant of Synedrella nodiflora as well as its petroleum ether, carbon tetrachloride, dichloro-methane and aqueous soluble partitionates were evaluated by DPPH of (1, 1-diphenyl-2-picrylhydrazyl and phosphomolybdenum total antioxidant assay and compared with standard antioxidants butylated hydroxytoluene (BHT and ascorbic acid (ASA. The total phenolic content was also determined and expressed in gallic acid equivalent (mg of GAE/g of sample. A great variance was observed for polyphenol content as well as antioxidant activity (1.574-9.4136 mg GAE/g and DPPH IC50 10.52-31.25 μg/ml depending on the nature of solvent used to fractionate the crude extract. The result demonstrated that dichloromethane soluble fraction revealed the highest amount of phenolic compounds (9.4136 mg GAE/g and also had significant free radical scavenging activity (IC50 10.52 μg/ml. A positive correlation was observed between total phenolic content and total antioxidant activity of S. nodiflora having correlation coefficient (R2 of 0.9270. The general toxicity of the extractive was studied by brine shrimp lethality bioassay and from the results (LC50 0.023-0.122 μg/ml, it can be well predicted that the crude extract and the partitionate fractions contain cytotoxic principles and have considerable toxic potencies which supported the insecticidal uses of plant by the indigenous people.

  12. HYOSCINE BUTYL BROMIDE VERSUS DROTAVERINE HYDROCHLORIDE IN ACTIVE STAGE OF LABOUR-A COMPARATIVE STUDY OF RATE OF CERVICAL DILATATION

    Directory of Open Access Journals (Sweden)

    Misha Pepsi

    2014-05-01

    Full Text Available AIM: This study was conducted to compare the rate of cervical dilatation with hyoscine butyl bromide and drotaverine hydrochloride in active stage of labour. MATERIALS AND METHODOLOGY: This prospective study was conducted in the department of Obstetrics and Gynaecology. Inclusion Criteria: 1. All women with initial cervical dilatation of 3 cms. 2. When there is a slow rate of cervical dilatation of less than 1.5 cms per hour or decent of less than 1 cm per hour for nulliparous and if dilatation was less than 2cms per hour for a multigravida. 3. And all singleton and cephalic pregnancies were included in this study. Exclusion Criteria included complications like Antepartum haemorrhage, Breech, C.P.D. In this study 400 women were allocated into two groups to receive either Hyoscine butyl bromide or Drotaverine hydrochloride. Two hours after admission in the active stage of labour, progress of labour was reassessed. If the progress of labour was satisfactory, then the wait and watch policy was adopted. If there was no progress they were administered one of the two drugs. 200 patients were administered 10mg of hyoscine butyl bromide suppositories rectally, (GROUP-1 AND THE OTHER 200 WITH 40mg of drotaverine hydrochloride intravenously (GROUP-2. The progress of labour was monitored by the partogram. Not more than 3 doses of hyoscine butyl bromide were administered. RESULTS: The rate of cervical dilatation was 2 cms per hour in group 1 (Hyoscine butyl bromide as compared to 1cm per hour in group 2 (Drotaverine hydrochloride. The difference in rate of cervical dilatation in both the groups was statistically significant. CONCLUSION: There was significant improvement in the rate of cervical dilatation with Hyoscine butyl bromide group of patients. There was a significant reduction in the duration of active stage of labour, and there was no significant second and third stage complication when these drugs were used. No untoward side effects were noted when

  13. Study of glue extrusion after endoscopic N-butyl-2-cyanoacrylate injection on gastric variceal bleeding

    Institute of Scientific and Technical Information of China (English)

    Yan-Mei Wang; Liu-Fang Cheng; Nan Li; Kai Wu; Jun-Shan Zhai; Ya-Wen Wang

    2009-01-01

    AIM: To investigate glue extrusion after endoscopic N-butyl-2-cyanoacrylate injection on gastric variceal bleeding and to evaluate the long-term efficacy and safety of this therapy.METHODS: A total of 148 cirrhotic patients in our hospital with esophagogastric variceal bleeding (EGVB) were included in this study. N-butyl-2-cyanoacrylate was mixed with lipiodol in a 1:1 ratio and injected as a bolus of 1-3 mL according to variceal size. Patients underwent endoscopic follow-up the next week, fourth week, second month, fourth month, and seventh month after injection and then every 6 mo to determine the cast shape. An abdominal X-ray film and ultrasound or computed tomographic scan were also carried out in order to evaluate the time of variceal disappearance and complete extrusion of the cast. The average follow-up time was 13.1 mo.RESULTS: The instantaneous hemostatic rate was 96.2%. Early re-bleeding after injection in 9 cases (6.2%) was estimated from rejection of adhesive. Late re-bleeding occurred in 12 patients (8.1%) at 2-18 mo. The glue cast was extruded into the lumen within one month in 86.1% of patients and eliminated within one year. Light erosion was seen at the injection position and mucosa edema in the second week. The glue casts were extruded in 18 patients (12.1%) after one week and in 64 patients (42.8%) after two weeks. All kinds of glue clumping shapes and colors on endoscopic examination were observed in 127 patients (86.1%) within one month, including punctiform, globular, pillar and variform. Forty one patients (27.9%) had glue extrusion after 3 mo and 28 patients (28.9%) after six months. The extrusion time was not related to the injection volume of histoacryl. Obliteration was seen in 70.2% (104 cases) endoscopically. The main complication was re-bleeding resulting from extrusion. The prognosis of the patients depended on the severity of the underlying liver disease.CONCLUSION: Endoscopic injection of cyanoacrylate is highly effective for

  14. Carboxylesterase-involved metabolism of di-n-butyl phthalate in pumpkin (Cucurbita moschata) seedlings.

    Science.gov (United States)

    Lin, Qingqi; Chen, Siyuan; Chao, Yuanqing; Huang, Xiongfei; Wang, Shizhong; Qiu, Rongliang

    2017-01-01

    Uptake and accumulation by plants is a significant pathway in the migration and transformation of phthalate esters (PAEs) in the environment. However, limited information is available on the mechanisms of PAE metabolism in plants. Here, we investigated the metabolism of di-n-butyl phthalate (DnBP), one of the most frequently detected PAEs, in pumpkin (Cucurbita moschata) seedlings via a series of hydroponic experiments with an initial concentration of 10 mg L(-1). DnBP hydrolysis occurred primarily in the root, and two of its metabolites, mono-n-butyl phthalate (MnBP) and phthalic acid (PA), were detected in all plant tissues. The MnBP concentration was an order of magnitude higher than that of PA in shoots, which indicated MnBP was more readily transported to the shoot than was PA because of the former's dual hydrophilic and lipophilic characteristics. More than 80% of MnBP and PA were located in the cell water-soluble component except that 96% of MnBP was distributed into the two solid cellular fractions (i.e., cell wall and organelles) at 96 h. A 13-20% and 29-54% increase of carboxylesterase (CXE) activity shown in time-dependent and concentration-dependent experiments, respectively, indicated the involvement of CXEs in plant metabolism of DnBP. The level of CXE activity in root subcellular fractions was in the order: the cell water-soluble component (88-94%) > cell wall (3-7%) > cell organelles (3-4%), suggesting that the cell water-soluble component is the dominant locus of CXE activity and also the domain of CXE-catalyzed hydrolysis of DnBP. The addition of triphenyl phosphate, a CXE inhibitor, led to 43-56% inhibition of CXE activity and 16-25% increase of DnBP content, which demonstrated the involvement of CXEs in plant metabolism of DnBP. This study contributes to our understanding of enzymitic mechanisms of PAE transformation in plants.

  15. Effect of Mixed Solvent on Fabrication, Morphology and Monodispersity of Microspheres with Hydrophobic Poly(butyl methacrylate) Shells

    Institute of Scientific and Technical Information of China (English)

    XIAO Xincai; LU Cheng

    2012-01-01

    Monodisperse microspheres (mean diameter 200-300 nm) with polystyrene cores and poly(acrylamide-co-buty1 methacrylate) shells were prepared by using a free radical polymerization method.Moreover,the effect of mixed solvent on the preparation,morphology and monodispersity was investigated.The experimental results showed that solubility parameter of butyl methacrylate and solvent affected mainly the molding of monodisperse core-shell microspheres.When the microspheres were fabricated in a sequential synthesis process,addition of hydrophilic and organic solvent including butyl methacrylate led to spherical degree of the particles becoming worse,and the mean diameter of the microspheres decreased and the monodispersity became better with increasing the crosslinker methylenebisacrylamide dosage.

  16. 5,11,17,23-Tetra-tert-butyl-25,26,27,28-tetramethoxycalix[4]arene dichloromethane hemisolvate

    Directory of Open Access Journals (Sweden)

    Edwin Weber

    2008-04-01

    Full Text Available In the title compound, C48H64O4·0.5CH2Cl2, both crystallographically independent calixarene molecules display a partial cone conformation. Their crystal packing is stabilized by C—H...π contacts involving the methoxy groups. The solvent molecule is located interstitially between two calixarene units with C—H...Cl contacts to methoxy and tert-butyl groups. One tert-butyl residue of each calixarene molecule is disordered over two positions (occupancies 0.60/0.40 and 0.63/0.37, resulting in bond distances that deviate from ideal values. The tetramer calixarene molecules present models with approximate non-crystallographic Cs symmetry.

  17. Synthesis of 1-/sup 11/C-labelled ethyl, propyl, butyl and isobutyl iodides and examples of alkylation reactions

    Energy Technology Data Exchange (ETDEWEB)

    Laangstroem, B.; Antoni, G.; Gullberg, P.; Halldin, C.; Naagren, K.; Rimland, A.; Svaerd, H.

    1986-01-01

    New /sup 11/C-labelled precursors (1-/sup 11/C)ethyl,(1-/sup 11/C)propyl, (1-/sup 11/C)butyl, and (1-/sup 11/C)isobutyl iodides have been prepared by a 3-step reaction route using a one-pot system. The labelled iodides were obtained in 20-55% radiochemical yields and 65-95% radiochemical purities, with a total time for synthesis of the order of 10-14 min. The labelled iodides have been used in alkylation reactions with nitrogen, oxygen and carbon nucleophiles. The nitrogen alkylation reactions are exemplified by the synthesis of the analgetics N-(1-/sup 11/C-ethyl)iodocaine and N-(1-/sup 11/C-butyl) bupivacaine. The synthesis of 3-nitrophenyl(1-/sup 11/C)propyl ether is also presented in this paper as an example of an oxygen alkylation.

  18. Optimizing the Synthesis of Ethyl tert-Butyl Ether in Continuous Catalytic Distillation Column Using New Ion Exchange Resin Catalyst

    Institute of Scientific and Technical Information of China (English)

    Muhammad Umar; Yahia Abubakar Al-Hamed; Abdulraheem Al-Zahrani; Hisham Saeed Bamufleh

    2013-01-01

    Liquid phase synthesis of one of the important fuel oxygenate, ethyl tert-butyl ether (ETBE), from etha-nol and tert-butyl alcohol (TBA) has been studied in catalytic distillation column (CDC) using ion exchange resin catalyst CT-145H. A packed CDC of 1.2 m height and 50 mm diameter with indigenously developed reactive sec-tion packing was used to generate experimental data. Effect of different key variables on product purity in distillate, was investigated to find the optimum operating conditions for ETBE synthesis. The optimum conditions for 0.2 kg·s-1 of ethanol feed were found:reboiler duty of 375 W, molar feed ratio of 1︰1.3 of reactants, and reflux ratio of 7. Concentration profiles for each component along each column section at optimum conditions were also drawn. Neither output nor input multiplicity was observed at experimental conditions.

  19. Preparation and application of acidified/calcined red mud catalyst for catalytic degradation of butyl xanthate in Fenton-like process.

    Science.gov (United States)

    Shao, Luhua; Wei, Guangtao; Wang, Yizhi; Li, Zhongmin; Zhang, Linye; Zhao, Shukai; Zhou, Ming

    2016-08-01

    Acidified/calcined red mud (ACRM), a novel catalyst used in Fenton-like process, was prepared by acidification and calcination of red mud (RM). Catalyst characterization showed that iron phase of ACRM was mainly α-Fe2O3 and ACRM was a porous material with rough surface and loose structure. Degradation of butyl xanthate in Fenton-like process catalyzed by ACRM was investigated. Butyl xanthate was effectively degraded, and the degradation of butyl xanthate was well fitted by second order kinetic model. ACRM had an excellent long-term stability in a Fenton-like process. The possible mechanisms of hydroxyl radical production and butyl xanthate degradation in a Fenton-like process catalyzed by ACRM were presented.

  20. Experimental Measurements and Correlations Isobaric Vapor-Liquid Equilibria for Water + Acetic Acid + Sec-butyl Acetate at 101.3 kPa

    Institute of Scientific and Technical Information of China (English)

    LI Ling; HE Yong; WU Yanxiang; ZOU Wenhu

    2013-01-01

    Isobaric vapor-liquid equilibrium(VLE) data for acetic acid + sec-butyl acetate and water + acetic acid + sec-butyl acetate systems were determined at 101.3 kPa using a modified Rose type.The nonideality of the vapor phase caused by the association of the acetic acid was corrected by the chemical theory and Hayden-O'Connell method.Thermodynamic consistency was tested for the binary VLE data.The experimental data were correlated successfully with the Non-Random Two Liquids (NRTL) model.The Root Mean Square Deviation (RMSD) of the ternary system was 0.0038.The saturation vapor pressure of sec-butyl acetate at 329 to 385 K was measured by means of two connected equilibrium cells.The vapor pressures of water and sec-butyl acetate were correlated with the Antoine equation.The binary interaction parameters and the ternary VLE data were obtained from this work.

  1. Epoxidation and oxidation reactions using 1,4-butanediol dimethacrylate crosslinked polystyrene-supported tertiary butyl hydroperoxide

    Indian Academy of Sciences (India)

    M S Sheela; K Sreekumar

    2004-11-01

    1,4-Butanediol dimethacrylate (1,4-BDDMA) crosslinked polystyrene-supported -butyl hydroperoxide was employed in the epoxidation of olefins and oxidation of alcohols to carbonyl compounds. The reagent proved to be successful as a recyclable solid phase organic reagent with as much or more efficiency when compared to its monomeric counterpart. The extent of reaction was found to be dependent on various reaction parameters like solvent, temperature, molar concentration and presence of catalyst.

  2. Novel synthesis of 2-butyl-5chloro-3H-imidazole-4-carbaldehyde:A key intermediate of Losartan

    Institute of Scientific and Technical Information of China (English)

    Hai Bo Sun; Guo Jun Zheng; Ya Ping Wang; Xiang Jing Wang; Wen Sheng Xiang

    2009-01-01

    A novel method for synthesis of 2-butyl-5-chloro-3H-imidazole-4-carbaldehyde 2, a key intermediate of Losartan was reported. The compound 2 was synthesized from starting material dimethyl malonate 6 and n-valeronitrile 8 by six steps with an overall yield of 40%.The key step including the reaction of compound $ with POCI3/DMF followed by hydrolysis to give compound 2 with the yield of 68%.

  3. Biological Activity of Methyl tert-butyl Ether in Relation to Soil Microorganisms has a Negative Environmental Impact

    OpenAIRE

    Gholam H.S. Bonjar

    2005-01-01

    Fuel oxygenates are added to gasoline to enhance combustion efficiency of automobiles and reduce air pollution. Methyl tert-butyl ether (MTBE) is the most commonly used oxygenate because of its low cost, high-octane level and ease of blending with gasoline. However, due to its water solubility, high mobility and low biodegradability it leaches in soil subsurface at the speed of groundwater. Amending gasoline with MTBE has made a widespread contamination of groundwater, surface waters in coast...

  4. The synergic extraction of uranium (Ⅵ) with tri-n-butyl phosphate (TBP) and petroleum sulfoxides(PSO)/benzene

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The synergistic extraction of uranium (Ⅵ) from nitric acid aqueous solution with a mixture of tri-n-butyl phosphate (TBP) and petroleum sulfoxides(PSO) in benzene was studied. It has been found that the maximum synergistic extraction effect occurs where the molar ratio of PSO to TBP is one to two. The composition of the complex of synergistic extraction is UO2(NO3)2.TB P.PSO. The formation constant of the complex KTp=57.44.

  5. 1-Butyl-3-methylimidazolium Salts as New Catalysts to Produce Epoxy-anhydride Polymers with Improved Properties

    OpenAIRE

    Mikhail S. Fedoseev; Gruzdev, Matvey S.; Lubov F. Derzhavinskaya

    2014-01-01

    We report the curing process of epoxy oligomers by using isomethyltetrahydrophthalic anhydride catalyzed with 1-butyl-3-methylimidazolium salts. Catalytic action has been ascertained to be dependent on the nature of anion. Salts with (Br-) and (PO4-) anions appeared to be most active. Formation of salt adducts with epoxy resin and anhydride is shown. Polymers having higher values of strength and glass transition temperature—as compared with similar epoxy systems cured in the presence of terti...

  6. Biodegradation of methyl tert-butyl ether and other fuel oxygenates by a new strain, Mycobacterium austroafricanum IFP 2012.

    Science.gov (United States)

    François, Alan; Mathis, Hugues; Godefroy, Davy; Piveteau, Pascal; Fayolle, Françoise; Monot, Frédéric

    2002-06-01

    A strain that efficiently degraded methyl tert-butyl ether (MTBE) was obtained by initial selection on the recalcitrant compound tert-butyl alcohol (TBA). This strain, a gram-positive methylotrophic bacterium identified as Mycobacterium austroafricanum IFP 2012, was also able to degrade tert-amyl methyl ether and tert-amyl alcohol. Ethyl tert-butyl ether was weakly degraded. tert-Butyl formate and 2-hydroxy isobutyrate (HIBA), two intermediates in the MTBE catabolism pathway, were detected during growth on MTBE. A positive effect of Co2+ during growth of M. austroafricanum IFP 2012 on HIBA was demonstrated. The specific rate of MTBE degradation was 0.6 mmol/h/g (dry weight) of cells, and the biomass yield on MTBE was 0.44 g (dry weight) per g of MTBE. MTBE, TBA, and HIBA degradation activities were induced by MTBE and TBA, and TBA was a good inducer. Involvement of at least one monooxygenase during degradation of MTBE and TBA was shown by (i) the requirement for oxygen, (ii) the production of propylene epoxide from propylene by MTBE- or TBA- grown cells, and (iii) the inhibition of MTBE or TBA degradation and of propylene epoxide production by acetylene. No cytochrome P-450 was detected in MTBE- or TBA-grown cells. Similar protein profiles were obtained after sodium dodecyl sulfate-polyacrylamide gel electrophoresis of crude extracts from MTBE- and TBA-grown cells. Among the polypeptides induced by these substrates, two polypeptides (66 and 27 kDa) exhibited strong similarities with known oxidoreductases.

  7. Dietary exposure to benzoates (E210-E213), parabens (E214-E219), nitrites (E249-E250), nitrates (E251-E252), BHA (E320), BHT (E321) and aspartame (E951) in children less than 3 years old in France.

    Science.gov (United States)

    Mancini, F R; Paul, D; Gauvreau, J; Volatier, J L; Vin, K; Hulin, M

    2015-01-01

    This study aimed to estimate the exposure to seven additives (benzoates, parabens, nitrites, nitrates, BHA, BHT and aspartame) in children aged less than 3 years old in France. A conservative approach, combining individual consumption data with maximum permitted levels, was carried out for all the additives. More refined estimates using occurrence data obtained from products' labels (collected by the French Observatory of Food Quality) were conducted for those additives that exceeded the acceptable daily intake (ADI). Information on additives' occurrence was obtained from the food labels. When the ADI was still exceeded, the exposure estimate was further refined using measured concentration data, if available. When using the maximum permitted level (MPL), the ADI was exceeded for benzoates (1.94 mg kg(-1) bw day(-1)), nitrites (0.09 mg kg(-1) bw day(-1)) and BHA (0.39 mg kg(-1) bw day(-1)) in 25%, 54% and 20% of the entire study population respectively. The main food contributors identified with this approach were current foods as these additives are not authorised in specific infant food: vegetable soups and broths for both benzoates and BHA, delicatessen and meat for nitrites. The exposure estimate was significantly reduced when using occurrence data, but in the upper-bound scenario the ADI was still exceeded significantly by the age group 13-36 months for benzoates (2%) and BHA (1%), and by the age group 7-12 months (16%) and 13-36 months (58%) for nitrites. Measured concentration data were available exclusively for nitrites and the results obtained using these data showed that the nitrites' intake was below the ADI for all the population considered in this study. These results suggest that refinement of exposure, based on the assessment of food levels, is needed to estimate the exposure of children to BHA and benzoates for which the risk of exceeding the ADI cannot be excluded when using occurrence data.

  8. Silica-Supported Arsine Palladium(0) Complex: a Highly Active and Stereoselective Catalyst for Arylation of Butyl Acrylate and Acrylamide

    Institute of Scientific and Technical Information of China (English)

    蔡明中; 赵红; 胡文英

    2005-01-01

    A silica-supported arsine palladium(O) complex has been prepared from y-chloropropyltriethoxysilane via immobilization on fumed silica, followed by reaction with potassium diphenylarsenide and palladium chloride, and then reduction with hydrazine hydrate. The complex has been characterized by X-ray photoelectron spectroscopy (XPS) and it is a highly active and stereoselective catalyst for arylation of butyl acrylate and acrylamide with aryl halides, affording a variety of tram-butyl cinnamates and trans-cinnamamides in high yields.

  9. Is the tert-butyl group bulky enough to end-cap a pseudorotaxane with a 24-crown-8-ether wheel?

    Science.gov (United States)

    Tachibana, Yuya; Kihara, Nobuhiro; Furusho, Yoshio; Takata, Toshikazu

    2004-11-25

    Although rotaxane chemists have long believed that the tert-butyl group is bulkier than the cavity of dibenzo-24-crown-8-ether (DB24C8), it is essentially smaller than the cavity of DB24C8. The tert-butyl (or 4-tert-butylphenyl) group can actually function as an end-cap of DB24C8-based rotaxanes when the intercomponent interaction is effectively operative. When such attractive interaction is removed, deslippage occurs. [structure: see text

  10. Molecular structure and spectral investigations of 3,5-Di-tert-butyl-o-benzoquinone

    Science.gov (United States)

    Yilmaz, M.; Aydin, B.; Dogan, O.; Dereli, O.

    2017-01-01

    Conformational analysis of 3,5-Di-tert-butyl-o-benzoquinone molecule was performed and two stable conformers were determined by B3LYP/6-311++G(d,p). Using the most stable one, molecular structural parameters, vibrational frequencies were calculated by B3LYP/6-311++G(d,p), B3LYP/6-31G(d) and BLYP/6-31G(d,p) levels of theory. The FT-IR spectrum of the compound was recorded in the region 4000-550 cm-1. The Raman spectrum was also recorded in the region 3500-100 cm-1. Calculated results were compared with experimental counterparts. The best results were obtained from B3LYP/6-311++G(d,p) calculations. Experimental 13C and 1H NMR data of tittle compound were taken from literature and the calculated results compared with these data. Vibrational and NMR band assignments were performed. HOMO-LUMO energies, molecular electrostatic potentials and thermodynamic properties were also given for further investigations of our structure.

  11. Polymerization rate and mechanism of ultrasonically initiated emulsion polymerization of n-butyl acrylate.

    Science.gov (United States)

    Xia, Hesheng; Wang, Qi; Liao, Yongqin; Xu, Xi; Baxter, Steven M; Slone, Robert V; Wu, Shuguang; Swift, Graham; Westmoreland, David G

    2002-07-01

    The factors affecting the induction period and polymerization rate in ultrasonically initiated emulsion polymerization of n-butyl acrylate (BA) were investigated. The induction period takes only an instant in ultrasonically initiated emulsion polymerization of BA without any added initiator by enhancing the N2 flow rate. Increasing temperature, power output and SDS concentration, decreasing the monomer concentration results in further decreasing induction period and enhanced polymerization rate. Under optimized reaction conditions the conversion of BA reaches 92% in 11 min. The polymerization rate can be controlled by varying reaction parameters. The apparatus of ultrasonically initiated semi-continuous and continuous emulsion polymerization were set up and the feasibility was first studied. Based on the experimental results, a free radical polymerization mechanism for ultrasonically initiated emulsion polymerization was proposed, including the sources of the radicals, the process of radical formation, the locus of polymerization and the polymerization process. Compared with conventional emulsion polymerization, where the radicals come from thermal decomposition of a chemical initiator, ultrasonically initiated emulsion polymerization has attractive features such as no need for a chemical initiator, lower reaction temperature, faster polymerization rate, and higher molecular weight of the polymer prepared.

  12. N-Butyl-N-methylmorpholinium bis(trifluoromethanesulfonyl)imide-PVdF(HFP) gel electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ki-Sub; Park, Seung-Yeob; Yeon, Sun-Hwa; Lee, Huen [Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology, 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701 (Korea)

    2005-09-30

    Ionic liquid-polymer gels were prepared by incorporating N-butyl-N-methylmorpholinium bis(trifluoromethanesulfonyl)imide (Mor{sub 1,4}TFSI) and poly(vinylidene fluoride)-hexafluoropropylene copolymer (PVdF(HFP)) using three different methods in order to observe the variation of ionic conductivities according to the presence of propylene carbonate (PC) and various weight ratios between Mor{sub 1,4}TFSI and gel polymer electrolyte (GPE). Ionic conductivities for each gel polymer electrolyte were measured with increasing temperature. Ionic conductivities of the GPEs increased with increasing temperature and weight ratio of Mor{sub 1,4}TFSI. In addition, the addition of PC into GPE led to the improvement of ionic conductivities. Thermogravimetric analysis (TGA) showed the suggested gel polymer electrolytes composed of only ionic liquid and polymer were stable up to approximately 400 C. TGA and infrared spectroscopy data indicated that residual PC remains after evaporating PC in a vacuum oven, which did not affect the ionic conductivities. The GPEs containing PC displayed high conductivity (ca. 10{sup -2} S cm{sup -1}) at 60 C. (author)

  13. Transcatheter Arterial Embolization of Nonvariceal Upper Gastrointestinal Bleeding with N-Butyl Cyanoacrylate

    Energy Technology Data Exchange (ETDEWEB)

    Jae, Hwan Jun; Chung, Jin Wook; Jung, Ah Young; Lee, Whal; Park, Jae Hyung [Seoul National University Hospital, Institute of Radiation Medicine, Seoul (Korea, Republic of)

    2007-02-15

    To evaluate the clinical efficacy and safety of transcatheter arterial embolization (TAE) with N-Butyl Cyanoacrylate (NBCA) for nonvariceal upper gastrointestinal bleeding. Between March 1999 and December 2002, TAE for nonvariceal upper gastrointestinal bleeding was performed in 93 patients. The endoscopic approach had failed or was discarded as an approach for control of bleeding in all study patients. Among the 93 patients NBCA was used as the primary embolic material for TAE in 32 patients (28 men, four women; mean age, 59.1 years). The indications for choosing NBCA as the embolic material were: inability to advance the microcatheter to the bleeding site and effective wedging of the microcatheter into the bleeding artery. TAE was performed using 1:1 1:3 mixtures of NBCA and iodized oil. The angiographic and clinical success rate, recurrent bleeding rate, procedure related complications and clinical outcomes were evaluated. The angiographic and clinical success rates were 100% and 91% (29/32), respectively. There were no serious ischemic complications. Recurrent bleeding occurred in three patients (9%) and they were managed with emergency surgery (n = 1) and with a successful second TAE (n = 2). Eighteen patients (56%) had a coagulopathy at the time of TAE and the clinical success rate in this group of patients was 83% (15/18). TAE with NBCA is a highly effective and safe treatment modality for nonvariceal upper gastrointestinal bleeding, especially when it is not possible to advance the microcatheter to the bleeding site and when the patient has a coagulopathy.

  14. Effects of Assistant Solvents and Mixing Intensity on the Bromination Process of Butyl Rubber

    Institute of Scientific and Technical Information of China (English)

    王伟; 邹海魁; 初广文; 向阳; 彭晗; 陈建峰

    2014-01-01

    A slow bromination process of butyl rubber (IIR) suffers from low efficiency and low selectivity (S) of target-product. To obtain suitable approach to intensify the process, effects of assistant solvents and mixing inten-sity on the bromination process were systemically studied in this paper. The reaction process was found constantly accelerated with the increasing dosage and polarity of assistant solvent. Hexane with 30%(by volume) dichloro-methane was found as the suitable solvent component, where the stable conversion of 1,4-isoprene transferring to target product (xA1s) of 80.2%and the corresponding S of 91.2%were obtained in 5 min. The accelerated reaction process was demonstrated being remarkably affected by mixing intensity until the optimal stirring rate of 1100 r·min-1 in a stirred tank reactor. With better mixing condition, a further intensification of the process was achieved in a ro-tating packed bed (RPB) reactor, where xA1s of 82.6% and S of 91.9% were obtained in 2 min. The usage of the suitable solvent component and RPB has potential application in the industrial bromination process intensification.

  15. THERMOPHYSICAL PROPERTIES OF 1-BUTYL-3-METHYLIMIDAZOLIUM BIS(TRIFLUOROMETHYLSULFONYLIMIDE AT HIGH TEMPERATURES AND PRESSURES

    Directory of Open Access Journals (Sweden)

    R. Hamidova

    2015-03-01

    Full Text Available Abstract Pressure-density-temperature (p, ρ ,T data of the ionic liquid 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonylimide [BMIM][NTF2] at T = (273.15 to 413.15 K and pressures up to p =140 MPa are reported with an estimated experimental relative combined standard uncertainty of Δ ρ / ρ = ±(0.01 to 0.08% in density. The measurements were carried out with a newly constructed Anton-Paar DMA HPM vibration-tube densimeter. The system was calibrated using double-distilled water, aqueous NaCl solution, methanol, toluene and acetone. An empirical equation of state for fitting the (p, ρ ,T data of [BMIM][NTF2] has been developed as a function of pressure and temperature. This equation is used for the calculation of the thermophysical properties of the ionic liquid, such as isothermal compressibility, isobaric thermal expansibility, thermal pressure coefficient, internal pressure, isobaric and isochoric heat capacities, speed of sound and isentropic expansibility.

  16. Effect of nisin and butylated hydroxy anisole on storage stability of buffalo meat sausage.

    Science.gov (United States)

    Sureshkumar, S; Kalaikannan, A; Dushyanthan, K; Venkataramanujam, V

    2010-06-01

    The water activity of buffalo meat sausage was adjusted to 0.88 using humectants and by heat treatment. Nisin and butylated hydroxyanisole (BHA) were added to study the shelf life of sausage. The treatments were nisin 100 ppm + BHA 100 ppm (T3); nisin 100 ppm (T2); BHA 100 ppm (T1) and control (T0) without nisin and BHA. The sausages were vacuum packaged in polyethylene terephthalate (PET-poly) pouch and stored for 7 days at ambient conditions (35 ± 2°C, 70-80% RH). The pH of sausage increased during storage whereas the moisture content was higher in treatment T1. Tyrosine value was lowest (18.1 mg%) in T3. There was no significant difference among T0 and T1. The thiobarbituric acid reactive substances (TBARS) number of T1 and T3 were lower than that of T0 and T2. Nisin and BHA together exhibited a significant inhibitory effect on total viable count, staphylococcal, streptococcal and anaerobic counts. There was no significant difference in the yeast and mould counts among T1-T3. T3 had a better appearance, flavour, texture and overall acceptability scores up to 5 days. The product (T3) was acceptable up to 5(th) day of storage at 35 ± 2°C and 70-80% RH.

  17. Synthesis, characterization and application of 1-butyl-3-methylimidazolium tetrafluoroborate for extractive desulfurization of liquid fuel

    Directory of Open Access Journals (Sweden)

    Swapnil A. Dharaskar

    2016-07-01

    Full Text Available In the present paper the experimental data of extractive desulfurization of liquid fuel using 1-butyl-3-methylimidazolium tetrafluoroborate [BMIM]BF4 have been presented. The data of FTIR, 1H NMR and 13C NMR have been discussed for the molecular confirmation of synthesized [BMIM]BF4. Further, the thermal properties, conductivity, solubility, and viscosity analysis of the [BMIM]BF4 were carried out. The effects of reaction time, reaction temperature, sulfur compounds, and recycling of ionic liquid without regeneration on dibenzothiophene removal of liquid fuel were presented. In extractive desulfurization process, the removal of dibenzothiophene in n-dodecane was 73.02% for mass ratio of 1:1 in 30 min at 30 °C under the mild reaction conditions. The ionic liquids could be reused four times without a significant decrease in activity. Also, the desulfurizations of real fuels, multistage extraction were presented. The data and results provided in the present paper explore the significant insights of imidazoled ILs for extractive desulfurization of liquid fuels.

  18. Synthesis, characterization, and application of 1-butyl-3-methylimidazolium thiocyanate for extractive desulfurization of liquid fuel.

    Science.gov (United States)

    Dharaskar, Swapnil A; Wasewar, Kailas L; Varma, Mahesh N; Shende, Diwakar Z

    2016-05-01

    1-Butyl-3-methylimidazolium thiocyanate [BMIM]SCN has been presented on extractive desulfurization of liquid fuel. The FTIR, (1)H-NMR, and C-NMR have been discussed for the molecular confirmation of synthesized [BMIM]SCN. Further, thermal, conductivity, moisture content, viscosity, and solubility analyses of [BMIM]SCN were carried out. The effects of time, temperature, sulfur compounds, ultrasonication, and recycling of [BMIM]SCN on removal of dibenzothiophene from liquid fuel were also investigated. In extractive desulfurization, removal of dibenzothiophene in n-dodecane was 86.5 % for mass ratio of 1:1 in 30 min at 30 °C under the mild process conditions. [BMIM]SCN could be reused five times without a significant decrease in activity. Also, in the desulfurization of real fuels, multistage extraction was examined. The data and results provided in the present paper explore the significant insights of imidazolium-based ionic liquids as novel extractant for extractive desulfurization of liquid fuels.

  19. Biomarkers of exposure to aromatic hydrocarbons and methyl tert-butyl ether in petrol station workers.

    Science.gov (United States)

    De Palma, Giuseppe; Poli, Diana; Manini, Paola; Andreoli, Roberta; Mozzoni, Paola; Apostoli, Pietro; Mutti, Antonio

    2012-06-01

    This cross-sectional study was aimed at reconstructing the exposure to gasoline in 102 petrol station attendants by environmental and biological monitoring of benzene, toluene, ethylbenzene and xylene (BTEX) and biomonitoring of methyl tert-butyl ether (MTBE). Airborne BTEX were higher for manual refuelers than self-service assistants and were highly correlated with each other. Significant relationships were found between airborne BTX and the corresponding urinary solvents (U-BTX) and beween airborne B and urinary MTBE (U-MTBE). Smokers eliminated higher values of U-B, trans,trans-muconic (t,t-MA) and S-phenylmercapturic (S-PMA) acids but not U-MTBE. All these biomarkers were, however, significantly raised during the shift, independently from smoking. Linear regression confirmed that occupational exposure was a main predictor of U-MTBE, U-B and S-PMA values, both the latter confounded by smoking habits. The study supports the usefulness of biomonitoring even at low exposure levels.

  20. Nonfoaming Bubble Separation for Recovery of Butyl Acetate from Discharged Wastewater During Penicillin Production

    Institute of Scientific and Technical Information of China (English)

    孙兴华; 常志东; 胡欣; 申淑锋; 刘会洲

    2005-01-01

    Two nonfoaming bubble separation techniques, air stripping and solvent sublation, are presented and discussed in order to recover butyl acetate (BA) from discharged wastewater after solvent extraction of penicillin. Results show air stripping is not suitable for the recovery of BA from the wastewater. Axial concentration of BA had a noted maximum point along the column. In contrast, solvent sublation is very effective to recover BA from the wastewater. In solvent sublation experiments, axial concentration of BA along the column first increased and then decreased from the bottom to the top because of two primary mass transport processes. One is the transport by adsorption or attachment to ascending bubbles, and the other is by dispersion at water-solvent interface and by water film in organic solvent layer. In order to elucidate the high removal efficiency in solvent sublation, the microstructure of the wastewater was studied with optic microscope, which was showed to be an emulsion of BA in water at large concentration of BA. Solvent sublation can be successfully used in the removal of BA from its emulsion in the wastewater. The surface tension of simulated solution composed of lysozyme and BA was studied to understand mutual effect of biological materials and BA. Results show that lysozyme affects the adsorption of BA at air-water interface and they may form a complex between BA and lysozyme molecules.

  1. Study of the PVA hydrogel behaviour in 1-butyl-3-methylimidazolium tetrafluoroborate ionic liquid

    Directory of Open Access Journals (Sweden)

    2011-02-01

    Full Text Available The present paper aims at studying the behaviour of the poly(vinyl alcohol [PVA] cryogel in the presence of 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM]+[BF4]– aqueous solutions with various concentrations. The gravimetric method showed that the swollen PVA cryogels exhibit mechanically active behaviour. PVA cryogels showed shrinking in the presence of ionic liquid, (IL, and re-swelling in the presence of distilled water. The re-swelling is not completely reversible, due to the influence of the IL ions on the gel morphology. The Fourier transform infrared (FTIR spectra have indicated no chemical interaction between the PVA and the studied IL, but highlighted the gel crystallinity change as a function of IL concentration, as well as changes in the bound water amount. Rheological analyses showed dominating plastifying effect of the cation at a lower IL concentration and dominating kosmotropic effect of the anion at a higher IL concentration. A phenomenological kinetic equation that takes into account both fluxes of matters, in and out of the gel, is proposed, explaining the alteration of the gel properties when it comes in contact with BMIMBF4 solutions.

  2. Impetigo herpetiformis occurring during N-butyl-scopolammonium bromide therapy in pregnancy: case report.

    Science.gov (United States)

    Guerriero, C; Lanza Silveri, S; Sisto, T; Rosati, D; De Simone, C; Fossati, B; Pomini, F; Rotoli, M; Amerio, P; Capizzi, R

    2008-01-01

    Impetigo herpetiformis (IH) is a rare dermatosis arising during the third trimester of pregnancy which is generally considered as a form of pustular psoriasis of unknown aetiology. Clinically it is characterized by erythematous plaques surrounded by sterile pustules associated with fever, diarrhea, sweating and increasing risk of stillbirth for placental insufficiency. We describe a case of developed erythematous plaques surrounded by pustules localised initially to the trunk of a 35-year-old woman at the 34th week of gestation after 5 days of treatment with N-Butyl-Scopolammonium, and which later involved the upper and lower limbs. Skin histology confirmed the diagnosis of generalised pregnancy pustular psoriasis (impetigo herpetiformis). IH is reported to be associated with hypocalcemia, hypoparathyroidism, use of oral contraceptives and bacterial infections. This is the first report suggesting the potential role of drugs other than oral contraceptives in the pathogenetic mechanism of this disease. In this case an adverse cutaneous reaction to BB could be the cause of the development of Koebner isomorphism.

  3. Experimental investigation of incremental reactivity of di-tert-butyl peroxide

    Institute of Scientific and Technical Information of China (English)

    DU Lin; XU YongFu; GE MaoFa; JIA Long; YAO Li

    2007-01-01

    Large quantities of di-tert-butyl peroxide(DTBP)have been emitted into the troposphere due to human activities.Its role in the atmospheric photochemical reaction has not been understood.This study presents the results of the photochemical reactions of DTBP and NOx,which have been simulated in a self-made smog chamber under the temperature of(29±1)℃.Both the wall decays of ozone and NO2 could be neglected,compared to the results in simulative experiments.The effective intensity of UV light used in the experiments was 1.28x10-3s-1,which was expressed by the rate constant of NO2 photolysis in purified air.The reaction mechanism was proposed according to our results and reports of other researchers.The maximum values of incremental reactivity(IR)in the three simulative experiments were 9.53x10-2,5.23x10-2 and 3.78x10-2,respectively.The incremental reactivity decreased with the increase of initial concentrations of DTBP.The IR value of DTBP obtained in this study was comparable to that of acetylene reported in our previous research.

  4. The Effect of Tertiary Butyl Hydroquinone on the Biodegradability of Palm Olein

    Directory of Open Access Journals (Sweden)

    Emmanuel ALUYOR

    2009-07-01

    Full Text Available Poor oxidative stability is demonstrated by most vegetable oils especially in industrial situations. Antioxidants are widely used for overcoming poor oxidative stability in vegetable oils. The adverse effect of additives on the overall biodegradability of vegetable oil based industrial fluids could however be a concern. Biodegradability provides an indication of the persistence of any particular substance in the environment. The superior biodegradation of vegetable oils in comparison with mineral based oils has been demonstrated severally, leaving scientists with the lone challenge of finding economic and safe means to improve their working efficiency in terms of their poor oxidative stability. This study investigated the extent to which the use of the antioxidant Tertiary butyl hydroquinone (TBHQ in palm olein impaired biodegradability, and described the relationship between antioxidant loading and biodegradability. Increased antioxidant loading resulted in a matching decrease in biodegradability. Using the total cumulative oxygen depletion value of pure refined palm olein at the end of the 28 day period as a standard of comparison, a 0.02% concentration of TBHQ in palm olein resulted in a 25% loss in biodegradability; a 2% concentration of TBHQ resulted in a 56.5% loss in biodegradability. At 6% TBHQ concentration, no biodegradation was observed in the palm olein sample studied.

  5. Venting Design for Di-tert-butyl Peroxide Runaway Reaction Based on Accelerating Rate Calorimeter Test

    Institute of Scientific and Technical Information of China (English)

    魏彤彤; 蒋慧灵

    2012-01-01

    In order to design the relief system size of di-tert-butyl peroxide(DTBP) storage tanks,the runaway re-action of DTBP was simulated by accelerating rate calorimeter(ARC).The results indicated that under adiabatic conditions the initial exothermic temperature was 102.6 ℃,the maximum self-heating rate was 3.095×107 ℃·min-1,the maximum self-heating temperature was 375.9 ℃,and the pressure produced by unit mass was 4.512 MPa·g-1.Judged by ARC test,the emergency relief system for DTBP was a hybrid system.Based on Design Institute for Emergency Relief System(DIERS) method,the releasing mass flow rate W was determined by Leung methods,and the mass velocity G was calculated by two modified Omega methods.The two relief sizes calculated by monograph Omega method and arithmetic Omega method are close,with only 0.63% relative error.The monograph Omega method is more convenient to apply.

  6. Crystal structure of 5-tert-butyl-10,15,20-triphenylporphyrin

    Directory of Open Access Journals (Sweden)

    Keith J. Flanagan

    2016-02-01

    Full Text Available In the title free base porphyrin, C42H34N4, the neighbouring N...N distances in the center of the ring vary from 2.818 (8 to 2.998 (8 Å and the phenyl rings are tilted from the 24-atom mean plane at angles varying between 62.42 (2–71.63 (2°. The NH groups are involved in intramolecular bifurcated N—H...(N,N hydrogen bonds. The Ca—Cm—Ca angles vary slightly for the phenyl rings, between 124.19 (18–126.17 (18°. The largest deviation from the mean plane of the 24-atom macrocycle is associated with the meso carbon at the substituted tert-butyl position, which is displaced from the mean plane by 0.44 (2 Å. The free base porphyrin is characterized by a significant degree of ruffled (B1u distortion with contributions from domed (A2u and wave [Eg(y and Eg(x] modes. In the crystal, molecules are linked by a number of weak C—H...π interactions, forming a three-dimensional framework. The structure was refined as a two-component inversion twin.

  7. Long-term effects of in utero and lactational exposure to butyl paraben in female rats.

    Science.gov (United States)

    Guerra, Marina Trevizan; Sanabria, Marciana; Cagliarani, Stephannie Vieira; Leite, Gabriel Adan Araújo; Borges, Cibele Dos Santos; De Grava Kempinas, Wilma

    2017-03-01

    Parabens are used as preservatives in cosmetic, pharmaceutical, and food industries, and are frequently detected as contaminants in human fluids and tissues. The endocrine disrupting effects of parabens in female rodents include uterotrophic response, steroidogenesis impairment, and ovarian disturbances. The objective of this study was to determine the effects of maternal butyl paraben (BP) exposure on female sexual development. Pregnant Wistar rats were treated subcutaneously with either corn oil or BP at doses of 10, 100, or 200 mg/kg, from gestational day (GD) 12 until GD 20 for female foetal gonad evaluation, and from GD 12 until the end of lactation to evaluate sexual parameters on the female offspring. Immature female rats were also used in the uterotrophic assay to evaluate the possible estrogenic action of parabens. Our results revealed that, in this experimental protocol, BP did not show estrogenic activity at the doses used and did not impair sexual development and fertility capacity in the female rats, but impaired sexual behavior. We conclude that brain sexual development may be more sensitive to BP effects and we speculate that doses higher than 100 mg/kg (the male lowest observed adverse effect level (LOAEL) for rodent reproductive parameters) would be necessary to promote damages in the female reproduction, regarding the same protocol of exposure. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 776-788, 2017.

  8. Artificial Neural Network Approach to Predict Biodiesel Production in Supercritical tert-Butyl Methyl Ether

    Directory of Open Access Journals (Sweden)

    Obie Farobie

    2016-05-01

    Full Text Available In this study, for the first time artificial neural network was used to predict biodiesel yield in supercritical tert-butyl methyl ether (MTBE. The experimental data of biodiesel yield conducted by varying four input factors (i.e. temperature, pressure, oil-to-MTBE molar ratio, and reaction time were used to elucidate artificial neural network model in order to predict biodiesel yield. The main goal of this study was to assess how accurately this artificial neural network model to predict biodiesel yield conducted under supercritical MTBE condition. The result shows that artificial neural network is a powerful tool for modeling and predicting biodiesel yield conducted under supercritical MTBE condition that was proven by a high value of coefficient of determination (R of 0.9969, 0.9899, and 0.9658 for training, validation, and testing, respectively. Using this approach, the highest biodiesel yield was determined of 0.93 mol/mol (corresponding to the actual biodiesel yield of 0.94 mol/mol that was achieved at 400 °C, under the reactor pressure of 10 MPa, oil-to-MTBE molar ratio of 1:40 within 15 min of reaction time.

  9. Transcatheter Arterial Embolization of Arterial Esophageal Bleeding with the Use of N-Butyl Cyanoacrylate

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ji Hoon; Kim, Hyo Cheol; Chung, Jin Wook; Jae, Hwan Jun; Park, Jae Hyung [Seoul National University Hospita, Seoul (Korea, Republic of)

    2009-08-15

    To evaluate the clinical efficacy and safety of a transcatheter arterial embolization (TAE) with N-butyl cyanoacrylate (NBCA) for the treatment of arterial esophageal bleeding. Between August 2000 and April 2008, five patients diagnosed with arterial esophageal bleeding by conventional angiography, CT angiography or endoscopy, underwent a TAE with NBCA. We mixed NBCA with iodized oil at ratios of 1:1 to 1:4 to supply radiopacity and achieve a proper polymerization time. After embolization, we evaluated the angiographic and clinical success, recurrent bleeding, and procedure-related complications. The bleeding esophageal artery directly originated from the aorta in four patients and from the left inferior phrenic artery in one patient. Although four patients had an underlying coagulopathy at the time of the TAE, angiographic and clinical success was achieved in all five patients. In addition, no procedurerelated complications such as esophageal infarction were observed during this study. NBCA can be an effective and feasible embolic agent in patients with active arterial esophageal bleeding, even with pre-existing coagulopathy.

  10. Effect of tert-butyl hydroperoxide addition on spontaneous chemiluminescence in brain.

    Science.gov (United States)

    Azorin, I; Bella, M C; Iborra, F J; Fornas, E; Renau-Piqueras, J

    1995-12-01

    It is well known that light emission is related to lipid peroxidation in biological material, and that this process occurs spontaneously in the brain. tert-Butyl hydroperoxide (tBHP) is an organic peroxide widely used as initiator of free radical production in several biological systems. However, the prooxidant capacity of this compound remins unclear. To clarify its role in brain spontaneous autooxidation, rat brain homogenates were incubated with and without tBHP. Light emission and lipid peroxidation were measured by luminometry and the TBARs test, respectively. Several inhibitors of free radical-induced lipid peroxidation were also used. These inhibitors included ascorbate, EDTA, and desferrioxamine. Our results indicate that the pattern of light emission spontaneously produced in brain was different from that observed after the addition of tBHP to the homogenates, and that these differences depended on the tBHP concentration. The main difference was that tBHP caused a rapid light emission that reached its maximum more quickly than in the case of spontaneous emission. Addition of ascorbate resulted in an increase in chemiluminescence in presence of tBHP. In contrast, EDTA and desferrioxamine inhibited light emission in homogenates both with and without tBHP. The results of MDA determination were similar to those described, including the effect of inhibitors. A common feature in MDA and luminometric determinations was the dispersion of data. In conclusion, these results suggest that tBHP, under specific conditions, modify the kinetic pattern of brain spontaneous autooxidation.

  11. Biodegradation Characteristics of Environmental Endocrine Disruptor Di-n-butyl Phthalate

    Institute of Scientific and Technical Information of China (English)

    LIN WANG; QI-FANG LUO

    2005-01-01

    Objective The biodegradation characteristics of di-n-butyl phthalate (DBP), an environmental endocrine disruptor, were studied by the method of dominant bacteria and immobilized microorganisms. Methods Taking DBP as the only carbon source to acclimatize the collected activated sludge, the concentration of DBP increased progressively in the process of acclimatization. Plate streaking was used to separate 1 strain of the degradation dominant bacteria after acclimatization. Better conditions to degrade DBP by the bacterium could be obtained through orthogonal experiments and the bacterium was identified. Then the acclimated activated sludge was made to immobilize the microorganism using polyvinyl alcohol as entrapment agent. The immobilized microorganism degraded DBP at different conditions. Results The appropriate conditions to degrade DBP by the dominant bacteria were: degradation time, 32 h; DBP concentration, 200 mg/L; rate of shaking incubator, 100 r/min; pH, 7 and temperature, 30℃. DBP could be degraded by more than 95% under such conditions. The bacteria were identified as pseudomonas. The proliferated immobilized microorganisms degraded DBP more effectively and more adapted to temperature and pH than the free acclimated activated sludge. Conclusion One strain of DBP degradation dominant bacteria was separated from the acclimatized activated sludge. It could grow with DBP as the only carbon source and energy, and degraded DBP effectively. After having been immobilized and proliferated, the dominant bacteria could keep a higher biological activity and degrade DBP more effectively than activated sludge.

  12. Removal of a type of endocrine disruptors-di-n-butyl phthalate from water by ozonation

    Institute of Scientific and Technical Information of China (English)

    LI Hai-yan; QU Jiu-hui; LIU Hui-juan

    2006-01-01

    Ozonation of synthetic water containing a type of endocrine disruptor-di-n-butyl phthalate (DBP) was examined. Key impact factors such as pH, temperature, ionic strength, ozone dosage and initial DBP concentration were investigated. In addition, the activities of radicals on uncatalysed and catalysed ozonation were studied. The degradation intermediate products were followed and the kinetic of the ozonation were assessed as well. Results revealed that ozonation of DBP followed two mechanisms. Firstly, the reaction rate of direct ozonation was slower at lower pH, temperature, and ionic strength. Secondly, when these factors were increased for indirect radical reaction, higher percentage of DBP was removed with the increase of the initial ozone dosage and the decrease of the initial DBP concentration. In addition, tert-butanol, humic substances and Fe(Ⅱ) affected DBP ozonation through the radical pathway. It was determined that ozonation was restrained by adding tert-butanol for its radical inhibition effect. Furthermore, humic substances enhanced the reaction to some extent, but a slight negative effect would be encountered if the optimum dosage was exceeded. As a matter of fact, Mn(Ⅱ) affected the ozonation by "active sites" mechanism. In the experiment, three different kinds of intermediate products were produced during ozonation, but the amount of products for each one of them decreased as pH, temperature,ionic strength and initial ozone dosage increased. A kinetic equation of the reaction between ozone and DBP was obtained.

  13. Highly ordered cellulose II crystalline regenerated from cellulose hydrolyzed by 1-butyl-3-methylimidazolium chloride.

    Science.gov (United States)

    Ahn, Yongjun; Song, Younghan; Kwak, Seung-Yeop; Kim, Hyungsup

    2016-02-10

    This research focused on the preparation of highly ordered cellulose II crystalline by cellulose hydrolysis in ionic liquid, and the influence of molecular mobility on recrystallization of cellulose. The molar mass of cellulose was controlled by hydrolysis using 1-butyl-3-methylimidazolium chloride (BmimCl). The molecular mobility of cellulose dissolved in BmimCl was characterized by rheological properties. After characterization of cellulose solution and regeneration, change of molar mass and conversion to crystalline were monitored using gel-permeation chromatography and powder X-ray diffraction, respectively. The molar mass of the cellulose in BmimCl was remarkably decreased with an increase in duration time, resulting in better mobility and a lower conformational constraint below critical molar mass. The decrease in molar mass surprisingly increased the crystallinity up to ∼ 85%, suggesting a recrystallization rate dependence of the mobility. The correlation between the mobility and recrystallization rate represented quit different behavior above and below a critical molar mass, which strongly demonstrated to the effect of mobility on the conversion of amorphous state to crystalline structure.

  14. Photosonochemical degradation of butyl-paraben: optimization, toxicity and kinetic studies.

    Science.gov (United States)

    Daghrir, R; Dimboukou-Mpira, A; Seyhi, B; Drogui, P

    2014-08-15

    The objective of the present work is to evaluate the potential of a photosonolysis process for the degradation of butyl-paraben (BPB). After 120 min of treatment time, high removal of BPB was achieved by the photosonolysis (US/UV) process (88.0±0.65%) compared to the photochemical (UV) and the conventional ultrasonication (US) processes. Several factors such as calorimetric power, treatment time, pH and initial concentration of BPB were investigated. Using a 2(4) factorial matrix, the treatment time and the calorimetric power are the main parameters influencing the degradation rate of BPB. Subsequently, a central composite design methodology has been investigated to determine the optimal experimental parameters for BPB degradation. The US/UV process applied under optimal operating conditions (at a calorimetric power of 40 W during 120 min and under pH7) is able to oxidize around 99.2±1.4% of BPB and to record 43.3% of mineralization. During the US/UV process, BPB was mainly transformed into 1 hydroxy BPB, dihydroxy BPB, hydroquinone and 4-hydroxybenzoic acid. Microtox biotests (Vibrio fisheri) showed that the treated effluent was not toxic. The pseudo-first order kinetic model (k=0.0367 min(-1)) described very well the oxidation of BPB.

  15. Studying the Kinetics of n-Butyl-Cyanoacrylate Tissue Adhesive and Its Oily Mixtures

    Science.gov (United States)

    Nedvedova, Marie; Kresalek, Vojtech; Vaskova, Hana; Provaznik, Ivo

    2016-10-01

    This study deals with the measurement of the kinetics of tissue adhesives used for supporting the hemostasis and wound closure during surgical intervention. There are available several types of adhesives of different composition which is closely related with their application. When selecting an appropriate adhesive, the time of curing could play an important role because some applications may require very fast polymerization for prompt vessel or wound closure; conversely, some situations need slower solidification because of longer manipulation with the glue during surgery. The terahertz time-domain spectroscopy is used for studying the kinetics of the n-butyl-cyanoacrylate glue in this study. An oily substance is added to the glue samples to slow the reaction rate. The technique of attenuated total reflection is used in this application; the defined amount of glue sample or its mixture is applied on the silicon crystal and the terahertz response is measured in time. This time dependences are analyzed to find time constants for mathematical description of the glue kinetics. Further, the investigated samples were analyzed using light microscopy and Raman spectroscopy for description of the structures and compositions.

  16. Subchronic, reproductive, and maternal toxicity studies with tertiary butyl acetate (TBAC).

    Science.gov (United States)

    Faber, Willem; Kirkpatrick, Daniel; Coder, Pragati; Li, Abby; Borghoff, Susan; Banton, Marcy

    2014-04-01

    Tertiary-butyl acetate (TBAC) was tested for subchronic toxicity in rats and mice and reproductive toxicity in rats at inhalation concentrations of 0, 100, 400 or 1600ppm. An oral maternal toxicity study was conducted in rats at dose levels of 0, 400, 800, 1000 and 1600mgkg(-1)d(-1). In the inhalation studies, hematology, clinical chemistry, urinalysis, gross pathology and the majority of body weight and feed consumption values were unaffected. Exposure to TBAC at concentrations of 400ppm and higher caused transient hyperactivity in mice and some evidence of increased motor activity counts in male rats at the 1600ppm exposure level. TBAC caused α2u-globulin accumulation in male rat kidneys from all exposure groups and increased liver weights in 1600ppm rats and mice. Levels of thyroxin were decreased in male mice exposed to 1600ppm TBAC for 4weeks but otherwise thyroid endpoints were unaffected in rats and mice at either the 4 or 13weeks time points. There was no evidence or immunotoxicity or reproductive toxicity in rats. Pregnant rats receiving 1000mgkg(-1)d(-1) TBAC exhibited severe signs of acute neurotoxicity and decreased feed consumption and body weight gain. Fetal viability and growth were unaffected.

  17. Coverage dependent isomerisation behaviour of tetra-tert-butyl-imine on Au(111)

    Energy Technology Data Exchange (ETDEWEB)

    Leyssner, Felix; Koch, Matthias; Meyer, Stephan; Tegeder, Petra [Freie Universitaet Berlin, Fachbereich Physik, Arnimallee 14, D-14195 Berlin (Germany)

    2011-07-01

    High resolution electron energy loss spectroscopy (HREELS) is employed to analyze thermally activated changes in the geometrical structure of the photochromic molecular switch 3,3',5,5'-tetra-tert-butyl-imine (TBI) adsorbed on Au(111). Measurements have been performed for two coverage regimes: The monolayer and the bilayer regime. For both coverages all molecules are found in the trans state after deposition at sample temperatures of T=210 K, but conformational changes upon heating are observed, which are assigned to a trans to cis-isomerization. When heating the sample to T=440 K two different conformations are observed depending on the initial coverage. Annealing of a monolayer leads to an increasing number of cis isomers, pointing towards an inverted thermal isomerisation behaviour of TBI, since the trans-isomer is the more stable compound in solution. Whereas for a bilayer the temperature induced isomerization of the TBI can be monitored as well, but desorption of the second layer at T=440 K leads to the formation of a trans-monolayer. The fact that different molecular configurations are found for equal coverages annealed at the same temperature is highly surprising and shows that collective effects may govern the switching properties of molecular switches on surfaces.

  18. Oral subchronic immunotoxicity study of ethyl tertiary butyl ether in the rat.

    Science.gov (United States)

    Banton, Marcy I; Peachee, Vanessa L; White, Kimber L; Padgett, Eric L

    2011-01-01

    The potential for immunotoxicological effects of ethyl tertiary butyl ether (ETBE, CAS RN 637-92-3) was studied in young adult female Crl:CD(SD) rats following subchronic oral exposures. Rats were exposed by gavage once daily for 28 consecutive days to 0, 250, 500, or 1000 mg ETBE/kg body weight (BW)/day; a concurrent positive control group received four intraperitoneal injections of at 50 mg cyclophosphamide monohydrate (CPS)/kg/day on study Days 24-27. Immunotoxicity was evaluated using a splenic antibody-forming cell (AFC) assay to assess T-cell-dependent antibody responses in rats sensitized with sheep red blood cells (SRBC). All rats survived to the scheduled necropsy. There were no effects on clinical observations, body weights, feed or water consumption, or macroscopic pathology findings in the ETBE-treated rats. No ETBE-related effects were observed on absolute or relative (to final body weight) spleen or thymus weights, spleen cellularity, or on the specific (AFC/10(6) spleen cells) or total activity (AFC/spleen) of splenic IgM AFC to the T-cell-dependent antigen SRBC. CPS produced expected effects consistent with its known immunosuppressive properties and validated the appropriateness of the AFC assay. Based on the results of this study, ETBE did not suppress the humoral component of the immune system in female rats. The no-observed-effect level for immunotoxicity was the highest dosage tested at 1000 mg/kg/day.

  19. Hepatotumorigenicity of ethyl tertiary-butyl ether with 2-year inhalation exposure in F344 rats.

    Science.gov (United States)

    Saito, Arata; Sasaki, Toshiaki; Kasai, Tatuya; Katagiri, Taku; Nishizawa, Tomoshi; Noguchi, Tadashi; Aiso, Shigetoshi; Nagano, Kasuke; Fukushima, Shoji

    2013-05-01

    Carcinogenicity of ethyl tertiary-butyl ether (ETBE) was examined with inhalation exposure using F344/DuCrlCrlj rats. Groups of 50 male and 50 female rats, 6 week old at commencement, were exposed to ETBE at 0, 500, 1,500 or 5,000 ppm (v/v) in whole-body inhalation chambers for 6 h/day, 5 days/week for 104 weeks. A significant increase in the incidence of hepatocellular adenomas was indicated in males exposed at 5,000 ppm, but not in females at any concentration. In addition, significantly increased incidences of eosinophilic and basophilic cell foci were observed in male rats at 5,000 ppm. Regarding non-neoplastic lesions, rat-specific changes were observed in kidney, with an increase in the severity of chronic progressive nephropathy in both sexes at 5,000 ppm. Increased incidences of urothelial hyperplasia of the pelvis were observed at 1,500 ppm and above, and mineral deposition was apparent in the renal papilla at 5,000 ppm in males. There were no treatment-related histopathological changes observed in any other organs or tissues in either sex. The present 2-year inhalation study demonstrated hepatotumorigenicity of ETBE in male, but not in female rats.

  20. Prenatal developmental toxicity study of ethyl tertiary-butyl ether in rabbits.

    Science.gov (United States)

    Asano, Yuzo; Ishikura, Toshikazu; Kudoh, Kayoko; Haneda, Ryo; Endoh, Takako

    2011-07-01

    Ethyl tertiary-butyl ether (ETBE) is commonly used as an oxygenated gasoline additive. In this study, the prenatal developmental toxicity of ETBE was determined in rabbits. New Zealand white rabbits were given ETBE by gavage at 100, 300, or 1,000 mg/kg/day on gestational days (GDs) 6-27, and the pregnancy outcome was determined on GD 28. Neither death nor abortion occurred in the pregnant rabbits at any dose. Slightly and significantly suppressed maternal body-weight gain and transiently decreased maternal food consumption were found at 1,000 mg/kg/day during the administration period. At this dose, no changes in clinical or macroscopic finding were noted in dams. No treatment-related changes were observed in any dam treated at 300 mg/kg/day or less. There was no significant effect of ETBE on the numbers of corpora lutea, implantations, live fetuses, resorptions and dead fetuses, incidences of pre- and postimplantation loss, viability of fetuses, fetal body weight, sex ratio of fetuses, or weights of gravid uteri. No significant difference was detected in the incidences of fetuses with malformations or variations between the ETBE-treated and control groups. Also, no adverse effects on the progress of ossification were noted in fetuses of dams given ETBE. Based on these findings, it is concluded that the no observed adverse effect levels of ETBE were 300 mg/kg/day for dams and 1,000 mg/kg/day for fetuses in rabbits.

  1. Predicted and experimental crystal structures of ethyl-tert-butyl ether.

    Science.gov (United States)

    Hammer, Sonja M; Alig, Edith; Fink, Lothar; Schmidt, Martin U

    2011-04-01

    Possible crystal structures of ethyl-tert-butyl ether (ETBE) were predicted by global lattice-energy minimizations using the force-field approach. 33 structures were found within an energy range of 2 kJmol(-1) above the global minimum. Low-temperature crystallization experiments were carried out at 80-160 K. The crystal structure was determined from X-ray powder data. ETBE crystallizes in C2/m, Z = 4, with molecules on mirror planes. The ETBE molecule adopts a trans conformation with a (CH(3))(3)C-O-C-C torsion angle of 180°. The experimental structure corresponds with high accuracy to the predicted structure with energy rank 2, which has an energy of 0.54 kJmol(-1) above the global minimum and is the most dense low-energy structure. In some crystallization experiments a second polymorph was observed, but the quality of the powder data did not allow the determination of the crystal structure. Possibilities and limitations are discussed for solving crystal structures from powder diffraction data by real-space methods and lattice-energy minimizations.

  2. A one-generation reproductive toxicity study of ethyl tertiary butyl ether in rats.

    Science.gov (United States)

    Fujii, Sakiko; Yabe, Kaoru; Furukawa, Masatoshi; Matsuura, Masao; Aoyama, Hiroaki

    2010-11-01

    A one-generation reproductive toxicity study was conducted to evaluate the effects of ethyl tertiary butyl ether (ETBE), a bio-fuel, on reproduction of parental rats, as well as development and growth of their offspring at dose levels of 0, 100, 300 and 1000 mg/kg-d by gavage. No treatment-related changes were observed in either F0 parents or their F1 offspring in the 100 and 300 mg/kg groups in any parameters examined. Some parental animals in the 1000 mg/kg group exhibited transient salivation, possibly a reflex to a bitter taste of ETBE, immediately after dosing, although their body weights, food consumption, reproductive parameters, and gross pathological findings were not affected. Their absolute and relative liver weights increased significantly in the 1000 mg/kg group, suggesting enhanced activities of metabolic enzymes. Pup viability was slightly reduced during the early lactation period in the 1000 mg/kg group. These results lead to the conclusion that the no-observed-adverse-effect-level (NOAEL) of ETBE on both parental rats and their offspring is 300 mg/kg-d under the current study condition.

  3. Prenatal developmental toxicity study of ethyl tertiary-butyl ether in rats.

    Science.gov (United States)

    Aso, Sunao; Miyata, Katsumi; Takakura, Saori; Hoshuyama, Satsuki; Muroi, Takako; Kusune, Yuji; Ajimi, Shozo; Furukawa, Kotaro

    2014-01-01

    Ethyl tertiary-butyl ether (ETBE) is commonly used as an oxygenated gasoline additive. In this study, we evaluated its developmental toxicity in rats. ETBE was administered by gavage to 21 or 22 pregnant female Sprague-Dawley rats per group at dose levels of 0, 100, 300 and 1000 mg/kg/day from days 5 through 19 postcoitum to assess its effects on pregnant animals and their embryos and fetuses applied to the OECD testing guideline (no. 414) correspondingly. There were no toxicological effects attributable to ETBE regarding clinical signs, body weight, food intake, necropsy or examination at caesarean section in pregnant animals. There were also no toxicological effects on external, visceral and skeletal examinations of embryos and fetuses. These results indicate that, under the conditions of this study, ETBE had no toxicological effects on pregnant rats or their embryos and fetuses and that the no observed adverse effect level was 1000 mg/kg/day both for pregnant rats and their embryos and fetuses.

  4. No carcinogenicity of ethyl tertiary-butyl ether by 2-year oral administration in rats.

    Science.gov (United States)

    Suzuki, Masaaki; Yamazaki, Kazunori; Kano, Hirokazu; Aiso, Shigetoshi; Nagano, Kasuke; Fukushima, Shoji

    2012-01-01

    The carcinogenicity of ethyl tertiary-butyl ether (ETBE) was examined by oral administration using F344/DuCrlCrlj rats. Groups of 50 male and 50 female rats were given drinking water containing ETBE at doses of 0, 625, 2,500 or 10,000 ppm (w/w) for 104 weeks. No significant increase in the incidence of tumors was detected in any organ of either sex. Rat-specific non-neoplastic lesions were observed in the kidney: An increase in the severity of chronic progressive nephropathy was observed in the male and female 10,000 ppm groups, and increased incidences of urothelial hyperplasia of the pelvis and mineral deposition in the renal papilla were observed in the male 2,500 and 10,000 ppm groups. Besides these lesions, no treatment-related histopathological changes were observed in any organ or tissue in either sex. Thus, the present study demonstrated that a two year administration ETBE in the drinking water did not exert any carcinogenic effects in either male or female rats.

  5. Preparation and characterization of lignin based macromonomer and its copolymers with butyl methacrylate.

    Science.gov (United States)

    Liu, Xiaohuan; Wang, Jifu; Yu, Juan; Zhang, Mingming; Wang, Chunpeng; Xu, Yuzhi; Chu, Fuxiang

    2013-09-01

    Copolymerization of butyl methacrylate (BMA) with biobutanol lignin (BBL) was achieved by free-radical polymerization (FRP) using a lignin-based macromonomer. The lignin-based macromonomer containing acrylic groups was prepared by reacting acryloyl chloride with biobutanol lignin using triethylamine (TEA) as absorb acid agentin. From the results of elemental analysis and GPC, the average degree of polymerization (DP) of BBL was estimated to be five. A detailed molecular characterization has been performed, including techniques such as (1)H NMR, (13)C NMR and UV-vis spectroscopies, which provided quantitative information about the composition of the copolymers. The changes in the solubility of lignin-g-poly(BMA) copolymers in ethyl ether were dependent on the length of poly(BMA) side chain. TGA analysis indicated that the lignin-containing poly(BMA) graft copolymers exhibited high thermal stability. The bulky aromatic group of lignin increased the glass-transition temperature of poly(BMA). In order to confirm the main structure of copolymer, (AC-g-BBL)-co-BMA copolymer was also synthesized by atom transfer radical polymerization (ATRP), and the results revealed that the copolymer prepared by ATRP had the same solution behavior as that prepared by FRP, and the lignin-based macromonomer showed no homopolymerizability due to the steric hindrance. In addition, the lignin-co-BMA copolymer had a surprisingly higher molecular weight than poly(BMA) under the same reaction condition, suggesting that a branched lignin based polymer could be formed.

  6. Post-discharge treatment of air effluents polluted by butyl-mercaptan: the role of nitrate radical

    Science.gov (United States)

    Liu, Y. N.; Braci, L.; Cavadias, S.; Ognier, S.

    2011-03-01

    Dry air polluted by butyl-mercaptan was treated in a dielectric barrier discharge reactor at atmospheric pressure using air as plasmagene gas in discharge and post-discharge modes. The energy density was varied between 200 and 1300 J l-1. To assess the treatment efficiency, the concentrations of butyl-mercaptan, total volatile organic compounds (VOCs) and SO2 were determined in the exhaust gas. Whatever the energy density was, the treatment efficiency was better in the post-discharge mode. Butyl-mercaptan could be completely eliminated from 400 J l-1 and SO2 selectivity was always low, below 10%. Measurements of CO, CO2 and total VOCs indicated that 50-70% of the reaction products were condensed on the reactor wall in the form of micro-droplets, depending on the energy density. FTIR and XPS techniques were used to characterize the reaction products which were soluble in water. These analyses indicated that the reaction products contained oxygen, nitrogen and sulfur in an oxidized form. A reaction mechanism involving hydrogen abstraction from the -SH bond by the nitrate radical was proposed, pointing out the important role of nitrate radicals NO3 in the reactivity of air flowing post-discharge.

  7. Distribution Equilibrium of o-Phthalic Acid and trans-Butenedioic in Water and Di-n-butyl Phthalate

    Institute of Scientific and Technical Information of China (English)

    GAO Zhenghong; YANG Xiaorui; HU Chaoquan; LI Jiang

    2006-01-01

    The organic dissolvent(di-n-butyl phthalate)needs to be washed by water to recycle itself in the process of recovering maleic anhydride by organic dissolvent. The design and optimization of the extraction process require the distribution coefficients of the organic solutes, o-phthalic acid and trans-butenedioic in water and di-n-butyl phthalate, on which the extraction efficiency depends. In this study, the distribution coefficients of o-phthalic acid and trans-butenedioic in water and di-n-bu-tyl phthalate(DBP)at 298.15 K, 318.15 K and 333.15 K were determined respectively by acid-alkali titration. The dissociation constants of o-phthalic acid and trans-butenedioic at those temperatures were obtained by fitting the measured hydrogen-ion concentrations and the known solute concentrations in the aqueous solution containing the two organic solutes. Then the distribution constants were calculated. Both the distribution coefficients and the distribution constants increase along with the temperature increasing. And the distribution coefficients at 333.15 K are large enough to ensure the efficiency of extraction process. In addition, the mutual solubility of water and di-n-butyl phthalate at 298.15 K, 318.15 K and 333.15 K was also measured respectively by High Performance Liquid Chromatography and Karl Fischer Watertitration, which was not more than 0.5%(mass fraction).

  8. Aerobic degradation of methyl tert-butyl ether by a Proteobacteria strain in a closed culture system

    Institute of Scientific and Technical Information of China (English)

    ZHONG Wei-hong; CHEN Jian-meng; LU Zheng; CHEN Dong-zhi; CHEN Xiao

    2007-01-01

    The contamination of methyl tert-butyl ether (MTBE) in underground waters has become a widely concerned problem all over the world. In this study, a novel closed culture system with oxygen supplied by H2O2 was introduced for MTBE aerobic biodegradation. After 7 d, almost all MTBE was degraded by a pure culture, a member of β-Proteobacteria named as PM1, in a closed system with oxygen supply, while only 40% MTBE was degraded in one without oxygen supply. Dissolved oxygen (DO) levels of the broth in closed systems respectively with and without H2O2 were about 5-6 and 4 mg/L. Higher DO may improve the activity of monooxygemase, which is the key enzyme of metabolic pathway from MTBE to tert-butyl alcohol and finally to CO2, and may result in the increase of the degrading activity of PM1 cell. The purge and trap GC-MS result of the broth in closed systems showed that tert-butyl alcohol,isopronol and acetone were the main intermediate products.

  9. Evaluation of the antioxidant properties of propofol and its nitrosoderivative. comparison with homologue substituted phenols.

    Science.gov (United States)

    Rigobello, Maria Pia; Stevanato, Roberto; Momo, Federico; Fabris, Sabrina; Scutari, Guido; Boscolo, Rita; Folda, Alessandra; Bindoli, Alberto

    2004-03-01

    Propofol (2,6-diisopropylphenol), some substituted phenols (2,6-dimethylphenol and 2,6-ditertbutylphenol) and their 4-nitrosoderivatives have been compared for their scavenging ability towards 1,1-diphenyl-2-picrylhydrazyl and for their inhibitory action on lipid peroxidation. These products were also compared to the classical antioxidants butylated hydroxytoluene and butylated hydroxyanisole. When measuring the reactivity of the various phenolic derivatives with 1,1-diphenyl-2-picrylhydrazyl the following order of effectiveness was observed: butylated hydroxyanisole > propofol > 2,6-dimethylphenol > 2,6-di-tertbutylphenol > butylated hydroxytoluene. In cumene hydroperoxide-dependent microsomal lipid peroxidation, propofol acts as the most effective antioxidant, while butylated hydroxyanisole, 2,6-di-tertbutylphenol and butylated hydroxytoluene exhibit a rather similar effect, although lower than propofol. In the iron/ascorbate-dependent lipid peroxidation propofol, at concentrations higher than 10 microM, exhibits antioxidant properties comparable to those of butylated hydroxytoluene and butylated hydroxyanisole, 2,6-Dimethylphenol is scarcely effective in both lipoperoxidative systems. The antioxidant properties of the various molecules depend on their hydrophobic characteristics and on the steric and electronic effects of their substituents. However, the introduction of the nitroso group in the 4-position almost completely removes the antioxidant properties of the examined compounds. The nitrosation of the aromatic ring of antioxidant molecules and the consequent loss of antioxidant capacity can be considered a condition potentially occurring in vivo since nitric oxide and its derivatives are continuously formed in biological systems.

  10. Urinary methyl tert-butyl ether and benzene as biomarkers of exposure to urban traffic.

    Science.gov (United States)

    Campo, Laura; Cattaneo, Andrea; Consonni, Dario; Scibetta, Licia; Costamagna, Paolo; Cavallo, Domenico M; Bertazzi, Pier Alberto; Fustinoni, Silvia

    2011-02-01

    Methyl tert-butyl ether (MTBE) and benzene are added to gasoline to improve the combustion process and are found in the urban environment as a consequence of vehicular traffic. Herein we evaluate urinary MTBE (MTBE-U) and benzene (BEN-U) as biomarkers of exposure to urban traffic. Milan urban policemen (130 total) were investigated in May, July, October, and December for a total of 171 work shifts. Personal exposure to airborne benzene and carbon monoxide (CO), and atmospheric data, were measured during the work shift, while personal characteristics were collected by a questionnaire. A time/activity diary was completed by each subject during the work shift. Spot urine samples were obtained for the determination of MTBE-U and BEN-U. Median personal exposure to CO and airborne benzene were 3.3 mg/m(3) and 9.6 μg/m(3), respectively; median urinary levels in end-of-shift (ES) samples were 147 ng/L (MTBE-U) and 207 ng/L (BEN-U). The time spent on traffic duty at crossing was about 40% of work time. Multiple linear regression models, taking into account within-subject correlations, were applied to investigate the role of urban pollution, atmospheric conditions, job variables and personal characteristics on the level of biomarkers. MTBE-U was influenced by the month of sampling and positively correlated to the time spent in traffic guarding, CO exposure and atmospheric pressure, while negatively correlated to wind speed (R(2) for total model 0.63, P<0.001). BEN-U was influenced by the month and smoking habit, and positively correlated to urinary creatinine; moreover, an interaction between CO and smoking was found (R(2)=0.62, P<0.001). These results suggest that MTBE-U is a reliable marker for assessing urban traffic exposure, while BEN-U is determined mainly by personal characteristics.

  11. Ameliorative effect of butylated hydroxyanisole against ferric nitrilotriacetate-induced hepatotoxicity and oxidative stress in rats.

    Science.gov (United States)

    Ansar, S; Iqbal, M

    2015-11-01

    Ferric nitrilotriacetate (Fe-NTA) is a known renal carcinogen and has been shown to adversely induce oxidative stress and tissue toxicity after both acute and chronic exposure. Present studies were designed to study the hepatoprotective and antioxidant potential of butylated hydroxyanisole (BHA), a phenolic antioxidant used in foods on ferric nitrilotriacetate (Fe-NTA) induced hepatotoxicity in rats. Male albino rats of Wistar strain (4-6 weeks old) weighing 125-150 g were used in this study. Animals were given a single dose of Fe-NTA (9 mg/kg body weight, intraperitoneal) after a week's treatment with BHA. BHA was administered orally once daily for 7 days at doses of 1 and 2 mg/animal/day. The hepatoprotective activity was assessed using various biochemical parameters as serum transaminases (alanine transaminase (ALT), aspartate transaminase (AST)) and lactate dehydrogenase (LDH). Fe-NTA treatment increased ALT, AST, and LDH levels significantly when compared to the corresponding saline-treated group (p < 0.001). Fe-NTA also depleted the levels of glutathione and the activities of antioxidant enzymes namely glutathione reductase and glutathione-S-tranferase (p < 0.05). Pretreatment with BHA significantly decreased ALT, AST and LDH levels in a dose-dependent manner (p < 0.05). BHA also increased antioxidant enzymes level and decreased lipid peroxidation and hydrogen peroxide generation to 1.3-1.5-fold as compared to Fe-NTA-treated group. The results show the strong hepatoprotective activity of BHA which could be due to its potent antioxidant effects.

  12. Spin probing of supramolecular structures in 1-butyl-3-methyl-imidazolium tetrafluoroborate/water mixtures

    Science.gov (United States)

    Kattnig, Daniel R.; Akdogan, Yasar; Lieberwirth, Ingo; Hinderberger, Dariush

    2013-10-01

    We have systematically studied micro-heterogeneous mixtures of the room temperature ionic liquid 1-butyl-3-methyl-imidazolium tetrafluoroborate ([bmim+][BF4-]) and water using continuous wave electron paramagnetic resonance (CW EPR) and the spin-probing methodology. Using cryo TEM, a mesoscopic picture of the micro-heterogeneous mixtures could be revealed. Six spin-probes differing in polarity, charge and Lewis basicity have been used to map the dependence of the micro-polarity and rotation motion of the probe on the ionic liquid (IL) concentration. The electron paramagnetic resonance (EPR) spectra of all probe molecules have been found to be unimodal. The critical aggregation concentration has been determined and the local water concentration sensed by the probes extracted from the Mukerjee hydrophilicity index. Surprisingly, four probes of the piperidinoxyl type were found to sense very similar local water concentrations irrespective of the substituent, monovalent ionic or H-bonding, at the 4-position. Using a simple geometrical model of the primary IL aggregates observed in the micro-heterogeneous concentration range, we show that these probes cannot be statically located within the aggregates on the EPR timescale. Instead, diffusive trajectories of the probe molecules extend into the aqueous phase, i.e. aqueous and [bmim+][BF4-]-rich phases are sampled by the probes in swift succession. No details of the internal structure of the [bmim+][BF4-] aggregates can in general be elucidated by the spin-probing methodology under these conditions. On the other hand, the dianionic Fremy's salt binds to the surface of the IL aggregates thereby sampling predominantly the aqueous phase. At large IL concentrations, a micro-viscosity drastically smaller than the macroscopic viscosity is typically observed. Supplementary Materials (Figures S1-S5) for this paper are available online on the journal website.

  13. Risk characterization of methyl tertiary butyl ether (MTBE) in tap water.

    Science.gov (United States)

    Stern, B R; Tardiff, R G

    1997-12-01

    Methyl tertiary butyl ether (MTBE) can enter surface water and groundwater through wet atmospheric deposition or as a result of fuel leaks and spills. About 30% of the U.S. population lives in areas where MTBE is in regular use. Ninety-five percent of this population is unlikely to be exposed to MTBE in tap water at concentrations exceeding 2 ppb, and most will be exposed to concentrations that are much lower and may be zero. About 5% of this population may be exposed to higher levels of MTBE in tap water, resulting from fuel tank leaks and spills into surface or groundwater used for potable water supplies. This paper describes the concentration ranges found and anticipated in surface and groundwater, and estimates the distribution of doses experienced by humans using water containing MTBE to drink, prepare food, and shower/bathe. The toxic properties (including potency) of MTBE when ingested, inhaled, and in contact with the skin are summarized. Using a range of human toxic potency values derived from animal studies, margins of exposure (MOE) associated with alternative chronic exposure scenarios are estimated to range from 1700 to 140,000. Maximum concentrations of MTBE in tap water anticipated not to cause adverse health effects are determined to range from 700 to 14,000 ppb. The results of this analysis demonstrate that no health risks are likely to be associated with chronic and subchronic human exposures to MTBE in tap water. Although some individuals may be exposed to very high concentrations of MTBE in tap water immediately following a localized spill, these exposures are likely to be brief in duration due to large-scale dilution and rapid volatilization of MTBE, the institution of emergency response and remediation measures to minimize human exposures, and the low taste and odor thresholds of MTBE which ensure that its presence in tap water is readily detected at concentrations well below the threshold for human injury.

  14. Gene expression profiling of di-n-butyl phthalate in normal human mammary epithelial cells.

    Science.gov (United States)

    Gwinn, Maureen R; Whipkey, Diana L; Tennant, Lora B; Weston, Ainsley

    2007-01-01

    Studies show that female workers in the personal-care industry have an increased risk of developing cancer believed to be the result of increased exposure to toxic and/or carcinogenic chemicals found in cosmetics, hair dyes, and nail polish. One chemical found in multiple personal-care products, di-n-butyl phthalate (DBP), is a known endocrine disruptor and has been found in increased levels in women of childbearing age. The goal of this study was to elucidate mechanisms of phthalate toxicity in normal human cells to provide information concerning interindividual variation and gene-environment interactions. Normal human mammary epithelial cell strains were obtained from discarded tissues following reduction mammoplasty [Cooperative Human Tissue Network (sponsors: NCI/NDRI)]. Gene transcription in each cell strain was analyzed using high-density oligonucleotide DNA microarrays (U133A, Affymetrix) and changes in the expression of selected genes were verified by real-time polymerase chain reaction (PCR) (ABI). DNA microarrays were hybridized with total RNA that was collected after DBP treatment for 5 hr and 10 hr. RNA was harvested from the vehicle control (acetone) at 10 hr. Data Mining Tool software (Affymetrix) was used to separate genes in clusters based on their expression patterns over time. Only 57 genes were found to be altered in all four cell strains following exposure to DBP. These included genes involved in fertility (inhibin, placental growth factor), immune response (tumor necrosis factor induced protein), and antioxidant status (glutathione peroxidase). Data from this study will help clarify the role of DBP in reproductive toxicity, and yield biomarkers of exposure for future epidemiology studies.

  15. LIDEM unit for the production of methyl tert-butyl ether from butanes

    Energy Technology Data Exchange (ETDEWEB)

    Rudin, M.G.; Zadvornov, M.A.

    1994-09-01

    One of the basic problems in the production of motor fuels is how to obtain high-octane unleaded gasolines that will meet today`s ecological requirements. The term {open_quotes}reformulated gasolines{close_quotes} has come into general use throughout the world to denote fuels with a certain chemical composition. These gasolines consist of preselected components; as shown by worldwide experience, they must include oxygen-containing compounds that are distinguished by high octane numbers and low reactivities. Standards in effect in the United States, Japan, and certain Western European countries require that automotive gasolines must contain at least 2-4% by weight of oxygen-containing compounds (calculated as oxygen). In the last 15 years, in order to meet these requirements, production has been set up in various countries for the manufacture of high-octane oxygen-containing components known as oxygenates. The most common of these is methyl tert-butyl ether (MTBE), obtained by etherification of isobutene by methanol. Process technology developed by this last organization was used as the basis for constructing a unit in the Nizhnekamskneftekhim Production Association and at the Mazheikyai Petroleum Refinery in Lithuania. MTBE production has been held back mainly by a shortage of isobutene, which is obtained mainly from butane-butene cuts produced in cat crackers. In order to alleviate this shortage, it has been proposed that MTBE should be obtained from saturated C{sub 4} hydrocarbons that are recovered in processing oilfield associated gas, and also in the refinery from primary distillation units, catalytic reformers, and hydrocrackers. A working design was developed in 1991-1992 by Lengiproneftekhim for a basically new combination unit designed for the processing of saturated C{sub 4} hydrocarbons, which has been termed the LIDEM unit (Leningrad - isomerization - dehydrogenation - MTBE).

  16. Percutaneous Transportal Sclerotherapy with N-Butyl-2-Cyanoacrylate for Gastric Varices: Technique and Clinical Efficacy

    Energy Technology Data Exchange (ETDEWEB)

    Kwak, Hyo Sung; Han, Young Min [Chonbuk National University Medical School and Hospital, Jeonju (Korea, Republic of)

    2008-12-15

    This study was deigned to evaluate the technique and clinical efficacy of the use of percutaneous transportal sclerotherapy with N-butyl-2-cyanoacrylate (NBCA) for patients with gastric varices. Seven patients were treated by transportal sclerotherapy with the use of NBCA. For transportal sclerotherapy, portal vein catheterization was performed with a 6-Fr sheath by the transhepatic approach. A 5-Fr catheter was introduced into the afferent gastric vein and a microcatheter was advanced through the 5-Fr catheter into the varices. NBCA was injected through the microcatheter in the varices by use of the continuous single-column injection technique. After the procedure, postcontrast computed tomography (CT) was performed on the next day and then every six months. Gastroendoscopy was performed at one week, three months, and then every six months after the procedure. The technical success rate of the procedure was 88%. In six patients, gastric varices were successfully obliterated with 1-8 mL (mean, 5.4 mL) of a NBCA-Lipiodol mixture injected via a microcatheter. No complications related to the procedure were encountered. As seen on the follow-up endoscopy and CT imaging performed after six months, the presence of gastric varcies was not seen in any of the patients after treatment with the NBCA-Lipiodol mixture and the use of microcoils. Recurrence of gastric varices was not observed during the followup period. Worsening of esophageal varices occurred in four patients after transportal sclerotherapy. The serum albumin level increased, the ammonia level decreased and the prothrombin time increased at six months after the procedure (p < 0.05). Percutaneous transportal sclerotherapy with NBCA is useful to obliterate gastric varices if it is not possible to perform balloon-occluded retrograde transvenous obliteration.

  17. Effects of subchronic inhalation exposure to ethyl tertiary butyl ether on splenocytes in mice.

    Science.gov (United States)

    Li, Q; Kobayashi, M; Inagaki, H; Hirata, Y; Hirata, K; Shimizu, T; Wang, R-S; Suda, M; Kawamoto, T; Nakajima, T; Kawada, T

    2011-01-01

    Ethyl tertiary-butyl ether (ETBE) is a motor fuel oxygenate used in reformulated gasoline. The current use of ETBE in gasoline or petrol is modest but increasing. To investigate the effects of ETBE on splenocytes, mice were exposed to 0 (control), 500 ppm, 1750 ppm, or 5000 ppm of ETBE by inhalation for 6 h/day for 5 days/wk over a 6- or 13-week period. Splenocytes were harvested from the control and exposed mice, and the following cell phenotypes were quantified by flow cytometry: (1) B cells (PerCP-Cy5.5-CD45R/B220), (2) T cells (PerCP-Cy5-CD3e), (3) T cell subsets (FITC-CD4 and PE-CD8a), (4) natural killer (NK) cells (PE-NK1.1), and (5) macrophages (FITC-CD11b). Body weight and the weight of the spleen were also examined. ETBE-exposure did not affect the weight of the spleen or body weight, while it transiently increased the number of RBC and the Hb concentration. The numbers of splenic CD3+, CD4+, and CD8+ T cells, the percentage of CD4+ T cells and the CD4+/CD8+ T cell ratio in the ETBE-exposed groups were significantly decreased in a dose-dependent manner. However, ETBE exposure did not affect the numbers of splenic NK cells, B cells, or macrophages or the total number of splenocytes. The above findings indicate that ETBE selectively affects the number of splenic T cells in mice.

  18. Medium-term multi-organ carcinogenesis bioassay of ethyl tertiary-butyl ether in rats.

    Science.gov (United States)

    Hagiwara, Akihiro; Doi, Yuko; Imai, Norio; Nakashima, Hironao; Ono, Takahiro; Kawabe, Mayumi; Furukawa, Fumio; Tamano, Seiko; Nagano, Kasuke; Fukushima, Shoji

    2011-11-18

    The modifying potential of ethyl tertiary-butyl ether (ETBE) on tumor development was investigated in a medium-term multi-organ carcinogenesis bioassay using male F344 rats. Animals were sequentially given 5 carcinogens with different target sites in the first 4 weeks for multi-organ initiation. After one week they received ETBE by gavage at dose levels of 0 (control), 300 or 1000mg/kg/day until experimental week 28. Further groups were also given ETBE at doses of 0 or 1000mg/kg/day without prior carcinogen application. Incidences and multiplicities of follicular cell hyperplasias and neoplasms in the thyroid were significantly increased at dose levels of more than 300mg/kg/day. Combined incidences of squamous cell hyperplasias and papillomas of the forestomach were also significantly increased at 300 and 1000mg/kg/day. Incidences and multiplicities of adenocarcinomas in the colon were increased at 1000mg/kg/day. The numbers and areas of glutathione S-transferase placental form (GST-P) positive foci per unit area of the liver sections, and the incidence of hepatocellular adenomas were also significantly increased at 1000mg/kg/day, along with multiplicities of atypical hyperplasias of renal tubules of the kidney and the incidence of papillomatosis of the urinary bladder. This latter lesion was also seen at low incidence at 1000mg/kg/day without initiation. Thus, the current results indicate that ETBE has tumor promoting potential for the thyroid and forestomach at dose levels of 300mg/kg/day and more, and for the colon, liver, kidney and urinary bladder at 1000mg/kg/day, under the present experimental conditions.

  19. Physiologically based pharmacokinetic model for ethyl tertiary-butyl ether and tertiary-butyl alcohol in rats: Contribution of binding to α2u-globulin in male rats and high-exposure nonlinear kinetics to toxicity and cancer outcomes.

    Science.gov (United States)

    Borghoff, Susan J; Ring, Caroline; Banton, Marcy I; Leavens, Teresa L

    2017-05-01

    In cancer bioassays, inhalation, but not drinking water exposure to ethyl tertiary-butyl ether (ETBE), caused liver tumors in male rats, while tertiary-butyl alcohol (TBA), an ETBE metabolite, caused kidney tumors in male rats following exposure via drinking water. To understand the contribution of ETBE and TBA kinetics under varying exposure scenarios to these tumor responses, a physiologically based pharmacokinetic model was developed based on a previously published model for methyl tertiary-butyl ether, a structurally similar chemical, and verified against the literature and study report data. The model included ETBE and TBA binding to the male rat-specific protein α2u-globulin, which plays a role in the ETBE and TBA kidney response observed in male rats. Metabolism of ETBE and TBA was described as a single, saturable pathway in the liver. The model predicted similar kidney AUC0-∞ for TBA for various exposure scenarios from ETBE and TBA cancer bioassays, supporting a male-rat-specific mode of action for TBA-induced kidney tumors. The model also predicted nonlinear kinetics at ETBE inhalation exposure concentrations above ~2000 ppm, based on blood AUC0-∞ for ETBE and TBA. The shift from linear to nonlinear kinetics at exposure concentrations below the concentration associated with liver tumors in rats (5000 ppm) suggests the mode of action for liver tumors operates under nonlinear kinetics following chronic exposure and is not relevant for assessing human risk. Copyright © 2016 The Authors Journal of Applied Toxicology Published by John Wiley & Sons Ltd.

  20. Preparation and Catalytic Activity of SO42-/TiO-La2O3 in Synthesis of Butyl Butyrate

    Institute of Scientific and Technical Information of China (English)

    YANG Shui-jin; LUO Yi; BAI Ai-min; HU Zhen-zhu; CHEN Fang

    2004-01-01

    Butyl butyrate is a very important compound, which is transparent liquid and has the pear,apple flavor. Natural exist is in the fruit, such as apple, pear, banana, grape and strawberry, etc.Primarily used for to prepare the edible spice and is also widely used in industrial intermediate product, solvent and synthetic perfumery. Until now, there are many methods to synthesize it.Conventionally H2SO4 was reported, but it causes many problems, such as the erosion of equipment,easily causes the vice-reaction, difficulty for after-treatment, environment pollution etc. A new environmentally friendly catalyst, SO42-/TiO2-La2O3 was prepared. And catalytic activity of catalyst in esterification of n-butanoic acid and n-butyl alcohol with SO42-/TiO2-La2O3 as catalyst has been no report up to now. Therefore, studying on the synthetic catalyst has theoretical and practical significances. The catalytic activity of catalyst in esterification of n-butanoic acid and n-butyl alcohol was measured.In this paper, we fast reported the preparation of SO42-/riO2-La2O3 and discussed the factors influencing the synthesis catalyst. The catalyst rare earth solid superacid SO42-/TiO2-La2O3 was The precipitate was filtered and washed thoroughly with distilled water until chloride ions were free.furnace at 480 ℃ for 3 h, and finally stored in a desiccator until use.The factors influencing the synthesis were discussed and the best conditions were found out. The experiment indicated that this catalyst has the following advantage. The amount of catalyst was little and getting high yield, its product has a good quanlity and is favour of reducing erosion of equipment, avoiding environment pollution. The optimum conditions are: molar ratio of n-butanoic acid to n-butyl alcohol was 1:1.5, the quantity of catalyst was equal to 1.5% of feed stocks, the reaction temperature was 93-114 ℃, and the reaction time was 1.0 h. Rare earth solid superacid SO42-/TiO2-La2O3 is an excellent catalyst for

  1. Metabolism and elimination of methyl, iso- and n-butyl paraben in human urine after single oral dosage.

    Science.gov (United States)

    Moos, Rebecca K; Angerer, Jürgen; Dierkes, Georg; Brüning, Thomas; Koch, Holger M

    2016-11-01

    Parabens are used as preservatives in personal care and consumer products, food and pharmaceuticals. Their use is controversial because of possible endocrine disrupting properties. In this study, we investigated metabolism and urinary excretion of methyl paraben (MeP), iso-butyl paraben (iso-BuP) and n-butyl paraben (n-BuP) after oral dosage of deuterium-labeled analogs (10 mg). Each volunteer received one dosage per investigated paraben separately and at least 2 weeks apart. Consecutive urine samples were collected over 48 h. In addition to the parent parabens (free and conjugated) which are already used as biomarkers of internal exposure and the known but non-specific metabolites, p-hydroxybenzoic acid (PHBA) and p-hydroxyhippuric acid (PHHA), we identified new, oxidized metabolites with hydroxy groups on the alkyl side chain (3OH-n-BuP and 2OH-iso-BuP) and species with oxidative modifications on the aromatic ring. MeP represented 17.4 % of the dose excreted in urine, while iso-BuP represented only 6.8 % and n-BuP 5.6 %. Additionally, for iso-BuP, about 16 % was excreted as 2OH-iso-BuP and for n-BuP about 6 % as 3OH-n-BuP. Less than 1 % was excreted as ring-hydroxylated metabolites. In all cases, PHHA was identified as the major but non-specific metabolite (57.2-63.8 %). PHBA represented 3.0-7.2 %. For all parabens, the majority of the oral dose captured by the above metabolites was excreted in the first 24 h (80.5-85.3 %). Complementary to the parent parabens excreted in urine, alkyl-chain-oxidized metabolites of the butyl parabens are introduced as valuable and contamination-free biomarkers of exposure.

  2. Obtaining of the antioxidants by supercritical fluid extraction

    Directory of Open Access Journals (Sweden)

    Babović Nada V.

    2011-01-01

    Full Text Available One of the important trends in the food industry today is demand for natural antioxidants from plant material. Synthetic antioxidants such as butylated hydroxytoluene (BHT, and butylated hydroxyanisole (BHA are now being replaced by the natural antioxidants because of theirs possible toxicity and as they may act as promoters of carcinogens. The natural antioxidants may show equivalent or higher antioxidant activity than the endogenous or the synthetic antioxidants. Thus, great effort is being devoted to the search for alternative and cheap sources of natural antioxidants, as well as to the development of efficient and selective extraction techniques. The supercritical fluid extraction (SFE with carbon dioxide is considered to be the most suitable method for producing natural antioxidants for the use in food industry. The supercritical extract does not contain residual organic solvents as in conventional extraction processes, which makes these products suitable for use in food, cosmetic and pharmaceutical industry. The recovery of antioxidants from plant sources involves many problematic aspects: choice of an adequate source (in terms of availability, cost, difference in phenolic content with variety and season; selection of the optimal recovery procedure (in terms of yield, simplicity, industrial application, cost; chemical analysis of extracts (for optimization purposes a fast colorimetric method is more preferable than a chromatographic one; evaluation of the antioxidant power (preferably by the different assay methods. The paper presents information about different operational methods for SFE of bioactive compounds from natural sources. It also includes the various reports on the antioxidant activity of the supercritical extracts from Lamiaceae herbs, in comparison with the activity of the synthetic antioxidants and the extracts from Lamiaceae herbs obtained by the conventional methods.

  3. RP-HPLC/MS/MS Analysis of the Phenolic Compounds, Antioxidant and Antimicrobial Activities of Salvia L. Species

    Science.gov (United States)

    Tohma, Hatice; Köksal, Ekrem; Kılıç, Ömer; Alan, Yusuf; Yılmaz, Mustafa Abdullah; Gülçin, İlhami; Bursal, Ercan; Alwasel, Saleh H.

    2016-01-01

    The identification and quantification of the phenolic contents of methanolic extracts of three Salvia L. species namely S. brachyantha (Bordz.) Pobed, S. aethiopis L., and S. microstegia Boiss. and Bal. were evaluated using reverse phase high performance liquid chromatography, UV adsorption, and mass spectrometry (RP-HPLC/MS). In order to determine the antioxidant capacity of these species, cupric ions (Cu2+) reducing assay (CUPRAC) and ferric ions (Fe3+) reducing assay (FRAP) were performed to screen the reducing capacity and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay was employed for evaluation of the radical scavenging activity for both solvents. In further investigation, the antimicrobial activities of Salvia species were tested using the disc diffusion method against three Gram-positive and four Gram-negative microbial species, as well as three fungi species. The results showed that there is a total of 18 detectable phenols, the most abundant of which was kaempferol in S. microstegia and rosmarinic acids in S. brachyantha and S aethiopis. The other major phenols were found to be apigenin, luteolin, p-coumaric acid, and chlorogenic acid. All species tested showed moderate and lower antioxidant activity than standard antioxidants such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), and ascorbic acid. The ethanolic extracts of Salvia species revealed a wide range of antimicrobial activity. S. brachyantha and S. microstegia showed the highest antimicrobial activities against B. subtilis, whereas S. aethiopis was more effective on Y. lipolytica. None of the extracts showed anti-fungal activity against S. cerevisiae. Thus these species could be valuable due to their bioactive compounds. PMID:27775656

  4. RP-HPLC/MS/MS Analysis of the Phenolic Compounds, Antioxidant and Antimicrobial Activities of Salvia L. Species

    Directory of Open Access Journals (Sweden)

    Hatice Tohma

    2016-10-01

    Full Text Available The identification and quantification of the phenolic contents of methanolic extracts of three Salvia L. species namely S. brachyantha (Bordz. Pobed, S. aethiopis L., and S. microstegia Boiss. and Bal. were evaluated using reverse phase high performance liquid chromatography, UV adsorption, and mass spectrometry (RP-HPLC/MS. In order to determine the antioxidant capacity of these species, cupric ions (Cu2+ reducing assay (CUPRAC and ferric ions (Fe3+ reducing assay (FRAP were performed to screen the reducing capacity and 1,1-diphenyl-2-picrylhydrazyl (DPPH assay was employed for evaluation of the radical scavenging activity for both solvents. In further investigation, the antimicrobial activities of Salvia species were tested using the disc diffusion method against three Gram-positive and four Gram-negative microbial species, as well as three fungi species. The results showed that there is a total of 18 detectable phenols, the most abundant of which was kaempferol in S. microstegia and rosmarinic acids in S. brachyantha and S aethiopis. The other major phenols were found to be apigenin, luteolin, p-coumaric acid, and chlorogenic acid. All species tested showed moderate and lower antioxidant activity than standard antioxidants such as butylated hydroxyanisole (BHA, butylated hydroxytoluene (BHT, and ascorbic acid. The ethanolic extracts of Salvia species revealed a wide range of antimicrobial activity. S. brachyantha and S. microstegia showed the highest antimicrobial activities against B. subtilis, whereas S. aethiopis was more effective on Y. lipolytica. None of the extracts showed anti-fungal activity against S. cerevisiae. Thus these species could be valuable due to their bioactive compounds.

  5. Response of the antioxidant defense system to tert-butyl hydroperoxide and hydrogen peroxide in a human hepatoma cell line (HepG2).

    Science.gov (United States)

    Alía, Mario; Ramos, Sonia; Mateos, Raquel; Bravo, Laura; Goya, Luis

    2005-01-01

    The aim of this work was to investigate the response of the antioxidant defense system to two oxidative stressors, hydrogen peroxide and tert-butyl hydroperoxide, in HepG2 cells in culture. The parameters evaluated included enzyme activity and gene expression of superoxide dismutase, catalase, glutathione peroxidase, and activity of glutathione reductase. Besides, markers of the cell damage and oxidative stress evoked by the stressors such as cell viability, intracellular reactive oxygen species generation, malondialdehyde levels, and reduced glutathione concentration were evaluated. Both stressors, hydrogen peroxide and tert-butyl hydroperoxide, enhanced cell damage and reactive oxygen species generation at doses above 50 microM. The concentration of reduced glutathione decreased, and levels of malondialdehyde and activity of the antioxidant enzymes consistently increased only when HepG2 cells were treated with tert-butyl hydroperoxide but not when hydrogen peroxide was used. A slight increase in the gene expression of Cu/Zn superoxide dismutase and catalase with 500 microM tert-butyl hydroperoxide and of catalase with 200 microM hydrogen peroxide was observed. The response of the components of the antioxidant defense system evaluated in this study indicates that tert-butyl hydroperoxide evokes a consistent cellular stress in HepG2.

  6. Synthesis, characterization and investigation of catalytic activity of Cu1−CoFe2O4 nanocatalysts in -butylation of -cresol

    Indian Academy of Sciences (India)

    Reza Fareghi Alamdari; Zahra Hosseinabadi; Masoud Farhadi Khouzani

    2012-07-01

    In this work, tertiary butylation of -cresol was carried out in the presence of Cu1−CoFe2O4 (x = 0 to 1) nanocatalysts by employing methyl-tert-butyl ether (MTBE) and tert-butyl alcohol (TBA) as alkylation agents. Effects of temperature, mole ratio, type and catalyst composition, time and solvent in reaction conditions were investigated. These nanocatalysts were synthesized using hydrothermal method. The characterization of these catalysts was investigated by means of X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FT-IR). These nanocatalysts can be recovered and recycled. A good correlation was found between the activity, in terms of -cresol conversion and various product selectivities for this reaction, and also the acid-base properties of the catalysts. Nano-sized Cu0.5Co0.5Fe2O4, in comparison to the other nanocatalysts discussed in this report is the most active nanocatalyst. The only product of this reaction is 2--butyl -cresol with selectivity of 100% and -cresol conversion is 70%. The possible mechanism for this reaction system was discussed based on the reaction results. The reaction mechanism proposed involves the interaction of phenoxide from phenol and the tert-butyl cation from isobutene on Cu1−CoFe2O4.

  7. Generation of free radicals from organic hydroperoxide tumor promoters in isolated mouse keratinocytes. Formation of alkyl and alkoxyl radicals from tert-butyl hydroperoxide and cumene hydroperoxide.

    Science.gov (United States)

    Taffe, B G; Takahashi, N; Kensler, T W; Mason, R P

    1987-09-05

    The organic hydroperoxides tert-butyl hydroperoxide and cumene hydroperoxide are tumor promoters in the skin of SENCAR mice, and this activity is presumed to be mediated through the activation of the hydroperoxides to free radical species. In this study we have assessed the generation of free radicals from organic hydroperoxides in the target cell (the murine basal keratinocyte) using electron spin resonance. Incubation of primary isolates of keratinocytes from SENCAR mice in the presence of spin traps (5,5-dimethyl-1-pyrroline N-oxide or 2-methyl-2-nitrosopropane) and either tert-butyl hydroperoxide or cumene hydroperoxide resulted in the generation and detection of radical adducts of these spin traps. tert-Butyl alkoxyl and alkyl radical adducts of 5,5-dimethyl-1-pyrroline N-oxide were detected shortly after addition of tert-butyl hydroperoxide, whereas only alkyl radical adducts were observed with cumene hydroperoxide. Spin trapping of the alkyl radicals with 2-methyl-2-nitrosopropane led to the identification of methyl and ethyl radical adducts following both tert-butyl hydroperoxide and cumene hydroperoxide exposures. Prior heating of the cells to 100 degrees C for 30 min prevented radical formation. The radical generating capacity of subcellular fractions of these epidermal cells was examined using 5,5-dimethyl-1-pyrroline N-oxide and cumene hydroperoxide, and this activity was confined to the 105,000 X g supernatant fraction.

  8. tert-Butyl N-[6-(N,N-dipropylcarbamoyl-1,3-benzothiazol-2-yl]carbamate

    Directory of Open Access Journals (Sweden)

    Xin Fang

    2010-05-01

    Full Text Available The title compound C19H27N3O3S, crystallizes with two unique molecules in the asymmetric unit. The benzene ring of each benzothiazole unit carries a dipropylcarbamoyl substituent in the 6-position and a tert-butyl carbamate unit on each thiazole ring. In the crystal structure, intermolecular N—H...N and weak C—H...O hydrogen bonds form centrosymmetric dimers. Additional C—H...O contacts construct a three-dimensional network. A very weak C—H...π contact is also present.

  9. HYDROLYSIS TRANSFORMATION OF A POLYSTYRENE-b-POLY(tert-BUTYL ACRYLATE)COPOLYMER AND MICELLIZATION PROPERTIES OF THE HYDROLYZED COPOLYMER

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A very mild and extremely efficient hydrolysis method for transformation of polystyrene-b-poly(tert-butyl acrylate) (PS-b-PtBA) to polystyrene-b-poly(acrylic acid) (PS-b-PAA)was designed and carried out using more convenient and inexpensive chlorotrimethylsilane/sodium iodide as reagents. The hydrolysis product can self-assemble in aqueous media to give regular micelles with PS block forming the core and PAL4 block forming the corona, or in tetrahydrofuran (THF) to give reverse micelles with the hydrophilic block in the core.

  10. Role of intravenously administered hyoscine butyl bromide in retrograde terminal ileoscopy: A randomized, double-blinded, placebo-controlled trial

    Institute of Scientific and Technical Information of China (English)

    SP Misra; M Dwivedi

    2007-01-01

    AIM:To evaluated the role of hyoscine butyl bromide in facilitating retrograde ileoscopy.METHODS:Retrograde terminal ileoscopy was attempted in 200 consecutive patients undergoing colonoscopy. After intubation of the cecum and visualization of the ileocecal valve,butyl bromide injection or normal saline was given intravenously to the patients in a double blind random fashion. The pulse rate and oxygen saturation were measured continuously. After completion of the procedure,endoscopists were then asked to score the ease of intubation and the ease of visualization of the terminal ileum on a visual scale of 1 to 10. The patients were also asked to score the pain after receiving hyoscine butyl bromide injection on a score of 1 to 10.RESULTS:Terminal ileoscopy could be performed in 188 patients. The mean (SD) visual analogue score for the ease of intubation of the cecum was 7.4 (0.65) in the injection group and 5.9 (0.8) in the placebo group (P<0.001). The mean (SD) length of ileum visualized in the injection group was 14.4 (3.3) cm and 10.4 (2.7) cm in the placebo group (P<0.001). The mean (SD) visual analogue score for ease of visualization of the terminal ileum was 7.5 (0.69) in the injection group and 5.9 (0.7) in the placebo group (P<0.001). The pain score experienced by the patients was 6.5 (0.7) in the injection group and 6.7 (0.69) in the placebo group (P<0.008). Although the pulse rate increased significantly in patients receiving the drug,no statistically significant difference was noted in the oxygen saturation between the two groups either before or after administration of the drug. No complications were observed in either of the groups.CONCLUSION:Hyoscine butyl bromide injection is a useful adjunct in helping the intubation and visualizationof terminal ileum during colonoscopy.

  11. Effect of antioxidant tertiary butyl hydroquinone on the thermal and oxidative stability of sesame oil (sesamum indicum) by ultrasonic studies

    OpenAIRE

    Prasad, N; Siddaramaiah, Basavarajaiah; Banu, Mujeeda

    2014-01-01

    The aim of the current investigation is to evaluate the efficiency of tertiary butyl hydroquinone (TBHQ) as an antioxidant in sesame oil (sesamum indicum) by density, viscosity and ultrasonic velocity. The effects of varying amounts of TBHQ on the oxidation stability of sesame oil have been investigated. The antioxidant incorporated sesame oil system and control edible oil were subjected to heating at 180 ± 5 °C continuously for a period of 4 h per day for consecutive 4 days. The parameters u...

  12. Effect of antioxidant butylated hydroxyl anisole on the thermal or oxidative stability of sunflower oil (Helianthus Annuus) by ultrasonic

    OpenAIRE

    Murari, Satish Kumar; Shwetha, M. V.

    2015-01-01

    The aim of the current investigation was to evaluate the efficiency of butylated hydroxyl anisole (BHA) as an antioxidant in sunflower oil (Helianthus Annuus). The oxidation stability of sunflower oil have been investigated by the effects of varying amounts of BHA. The antioxidant incorporated sunflower oil system and control edible oil were subjected to heating at 180 ± 5 °C continuously for a period of 4 h per day for consecutive 4 days. The parameters used to assess the thermal degradation...

  13. Synthesis and chemical behaviour of 17a-butyl-3b,17b-dihydroxy-16-oximino-5-androstene (NOTE

    Directory of Open Access Journals (Sweden)

    KATARINA PENOV GASI

    2001-01-01

    Full Text Available Starting from 3b-hydroxy-16-oximino-5-androsten-17-one (1, the recently synthesized 16-oximino-17b-hydroxy-17a-butyl derivative 2 gave by the Beckmann fragmentation reaction with titanium(III chloride or p-toluenesulphonyl chloride the corresponding D-seco derivative 3. However, using acetic anhydride, in addition to the 3b-acetoxy D-seco derivative 4, the 17-aza D-homo derivative 5 was obtained. The structure of compound was proposed on the basis of NMR-spectroscopy.

  14. HYDROLYSIS TRANSFORMATION OF A POLYSTYRENE—b—POLY(tert—BUTYL ACRYLATE) COPOLYMER AND MICELLIZATION PROPERTIES OF THE HYDROLYZED COPOLYMER

    Institute of Scientific and Technical Information of China (English)

    SIZhihuai; LIHexian; 等

    2001-01-01

    A very mild and extremely efficient hydrolysis method for transformation of polystyrene-b-poly(tert-butyl acrylate)(PS-b-PtBA)to polystyrene-b-poly(acrylic acid)(PS-b-PAA) was designed and carried out using more convenient and inexpensive chlorotrimethylsilane/sodium iodide as reagents.The hydrolysis product can self-assemble in aqueous media to give regular micelles with PS block forming the core and PAA block forming the corona,or in tetrahydrofuran (THF) to give reverse micelles with the hydrophilic block in the core.

  15. 1-Butyl-3-methylimidazolium Salts as New Catalysts to Produce Epoxy-anhydride Polymers with Improved Properties

    Directory of Open Access Journals (Sweden)

    Mikhail S. Fedoseev

    2014-01-01

    Full Text Available We report the curing process of epoxy oligomers by using isomethyltetrahydrophthalic anhydride catalyzed with 1-butyl-3-methylimidazolium salts. Catalytic action has been ascertained to be dependent on the nature of anion. Salts with (Br- and (PO4- anions appeared to be most active. Formation of salt adducts with epoxy resin and anhydride is shown. Polymers having higher values of strength and glass transition temperature—as compared with similar epoxy systems cured in the presence of tertiary amines as catalysts—are prepared.

  16. STABILITY OF EMULSIFIER-FREE EMULSION COPOLYMERIZATION OF METHYL METHACRYLATE/ BUTYL ACRYLATE/SODIUM MONO(ETHYL POLYOXYETHYLENE) MALEATE

    Institute of Scientific and Technical Information of China (English)

    Mao-gen Zhang; Zhi-xue Weng; Zhi-ming Huang; Zu-ren Pan

    1999-01-01

    A series of new water-soluble bifunctional comonomers having both carboxyl and alkyl polyoxyethylene groups, such as sodium mono(ethyl polyoxyethylene) maleate (ZE series) with various molecular weights of polyoxyethylene ethyl ether, were synthesized and characterized. The effects of the structural factor, the amount and feeding mode of the comonomers, the initiator concentration and polymerization temperature on the stability of emulsifier-free emulsion copolymerization of methyl methacrylate (MMA) and butyl acrylate (BA) in the presence of a small amount of ZE with potassium persulfate as initiator were investigated. Stable, almost monodispersed MMA/BA/ZE emulsifier-free latex particles were prepared.

  17. Di-n-butyl phthalate causes estrogenic effects in adult male Murray rainbowfish (Melanotaenia fluviatilis).

    Science.gov (United States)

    Bhatia, Harpreet; Kumar, Anupama; Ogino, Yukiko; Gregg, Adrienne; Chapman, John; McLaughlin, Mike J; Iguchi, Taisen

    2014-04-01

    Phthalic acid esters (PAEs) are a class of synthetic industrial chemicals commonly found in the aquatic environment worldwide. PAEs have been recognised as anti-androgens in male mammals but little is known about their endocrine disrupting effects in fish. This study investigated the effects of 7-day exposures to nominal (measured) concentrations of 125 (62), 250 (140), 500 (230) and 1,000 (383) μg/L of di-n-butyl phthalate (DnBP) on the biomarkers of reproduction in adult male Murray River rainbowfish (Melanotaenia fluviatilis) using molecular, biochemical and histological endpoints. None of the tested concentrations of DnBP had any effect on survival or the vital body indices of the fish. The sizes of spermatogonia, Type A and B spermatocytes and spermatids were significantly smaller relative to the controls after treatment with DnBP. This was accompanied by a significant increase in the proportion of spermatogonia in fish treated with 250-1,000 μg/L of DnBP in comparison to the unexposed fish. At the end of the exposure period, the expressions of the transcripts for the androgen receptors α and β were significantly elevated in the livers of the fish treated with 500 and 1,000 μg/L of DnBP. In addition, there was also an increase in the circulating concentrations of vitellogenin in the plasma in the higher treatment groups. An induction in the activity of aromatase was noted in the brains of 1,000 μg/L DnBP-treated fish. This was accompanied by an increase in the hepatic expression of the genes (here and later, whenever the phrase gene expression is used as a synonym for gene transcription although it is acknowledged that it is also regulated, e.g., by translation, mRNA stability and protein stability) encoding for the oestrogen receptors α and β and choriogenin L. Collectively, an increase in the proportion of spermatogonia in the testes, the upregulation of the genes for the oestrogen receptors and choriogenin in the liver, an induction in the brain

  18. Preparation of Seeding Type Immobilized Microorganisms and Their Degradation Characteristics on Di-n-Butyl Phthalate

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    To study the preparation of seeding type immobilized microorganisms and their degradation characteristics on di-n-butyl phthalate (DBP). Methods Diatomite, clinoptilolite, silk zeolite, and coal fly ash were chosen as reserved materials and modified. Their adsorption capacity and intensity in the bacteria were determined and the best carrier was picked out. The seeding type immobilized microorganisms were prepared by the best carrier and then it degraded DBP under different primary concentration, vibration rate, pH, temperature in the presence of metal compounds. Results The adsorption capacity of the modified coal fly ash, silk zeolite, clinoptilolite and zeolite was 44.2%, 71.6%, 84.0%, and 94.4%, respectively, which was 1.66, 1.49, 1.37, and 1.16 times as high as that of their natural state. Their adsorption intensity was 72.1%, 90.5%, 90.1%,and 91.1% in turn. The modified diatomite was selected to prepare the seeding type immobilized microorganisms. When the primary DBP concentration was 100 to 500 mg/L, the DBP-degraded rate of the immobilized microorganisms could be above 80%. The degradation activity of both the dissociative and immobilized microorganisms was higher in vibration than in stillness.When pH was 6.0 to 9.0, the DBP-degraded rate of the immobilized microorganisms was above 82%, which was higher than the dissociative microorganisms. When the temperature was between 20℃ and 40℃, the DBP-degraded rate could reach 84.5% in 24 h. The metal compounds could inhibit the degradation activity of both the dissociative and immobilized microorganisms. The degradation process of the immobilized microorganisms could be described by the first-order model.Conclusion The adsorption capacity of the diatomite, clinoptilolite, silk zeolite and coal fly ash on DBP-degrading bacteria can be improved obviously after they are modified. The modified diatomite is best in terms of its adsorption capacity and intensity. Its seeding type immobilized microorganisms could

  19. 甲苯与叔丁醇在补铝HM沸石催化剂上的烷基化反应%Tert-butylation of toluene with tert-butyl alcohol over realuminated H-mordenite zeolite

    Institute of Scientific and Technical Information of China (English)

    周志伟; 武文良; 王军; 曾崇余

    2009-01-01

    The realuminated H-mordenite catalysts(HM1-4)treated with difirerent concentrations of NaOH and NaAlO2 aqueous solutions were prepared,and characterized by inductively coupled plasma(ICP),X-ray diffraction (XRD),Fourier transform-infrared spectroscopy(FT-I R)and temperature-programmed desorption of ammonia,They are of lower Si/Al ratio and higher acid amount while keeping a high relative crystallinity.Their catalytic performances were evaluated with the liquid-phase tert-butylation of toluene with tert-butyl alcohol in a 100 ml stainless steel batch reactor equipped with a stirrer.HM2 zeolite catalyst,obtained by treating HM in 0.1 mol.L-1 NaOH followed bv 0.05 mol.L-1 NaAIO2 aqueous solution,shows a higher catalytic activity because of its highest acid amount.For HM2 catalyst the influcnces of reaction conditions on catalytic perfclrmance were investigated.The conversion of toluene iS 50.3%and the selectivity of p-tert-butyrltoluene is 74.7%at a temperature of 180°C,2 of molar ratio of tert-butyI alcohol to toluene.4h of reaction time and 0.2 of M(catalyst)/M(toluene).

  20. Vapor intrusion risk of fuel ether oxygenates methyl tert-butyl ether (MTBE), tert-amyl methyl ether (TAME) and ethyl tert-butyl ether (ETBE): A modeling study.

    Science.gov (United States)

    Ma, Jie; Xiong, Desen; Li, Haiyan; Ding, Yi; Xia, Xiangcheng; Yang, Yongqi

    2017-06-15

    Vapor intrusion of synthetic fuel additives represents a critical yet still neglected problem at sites contaminated by petroleum fuel releases. This study used an advanced numerical model to investigate the vapor intrusion potential of fuel ether oxygenates methyl tert-butyl ether (MTBE), tert-amyl methyl ether (TAME), and ethyl tert-butyl ether (ETBE). Simulated indoor air concentration of these compounds can exceed USEPA indoor air screening level for MTBE (110μg/m(3)). Our results also reveal that MTBE has much higher chance to cause vapor intrusion problems than TAME and ETBE. This study supports the statements made by USEPA in the Petroleum Vapor Intrusion (PVI) Guidance that the vertical screening criteria for petroleum hydrocarbons may not provide sufficient protectiveness for fuel additives, and ether oxygenates in particular. In addition to adverse impacts on human health, ether oxygenate vapor intrusion may also cause aesthetic problems (i.e., odour and flavour). Overall, this study points out that ether oxygenates can cause vapor intrusion problems. We recommend that USEPA consider including the field measurement data of synthetic fuel additives in the existing PVI database and possibly revising the PVI Guidance as necessary.

  1. Determination of low level methyl tert-butyl ether, ethyl tert-butyl ether and methyl tert-amyl ether in human urine by HS-SPME gas chromatography/mass spectrometry.

    Science.gov (United States)

    Scibetta, Licia; Campo, Laura; Mercadante, Rosa; Foà, Vito; Fustinoni, Silvia

    2007-01-02

    Methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE) and tert-amyl methyl ether (TAME) are oxygenated compounds added to gasoline to enhance octane rating and to improve combustion. They may be found as pollutants of living and working environments. In this work a robotized method for the quantification of low level MTBE, ETBE and TAME in human urine was developed and validated. The analytes were sampled in the headspace of urine by SPME in the presence of MTBE-d12 as internal standard. Different fibers were compared for their linearity and extraction efficiency: carboxen/polydimethylsiloxane, polydimethylsiloxane/divinylbenzene, and polydimethylsiloxane. The first, although highly efficient, was discarded due to deviation of linearity for competitive displacement, and the polydimethylsiloxane/divinylbenzene fiber was chosen instead. The analysis was performed by GC/MS operating in the electron impact mode. The method is very specific, with range of linearity 30-4600 ng L(-1), within- and between-run precision, as coefficient of variation, ethers was evaluated analysing the specimens of seven traffic policemen exposed to autovehicular emissions: using the calibration curve and the method of standard additions comparable levels of MTBE (68-528 ng L(-1)), ETBE (<6 ng L(-1)), and TAME (<6 ng L(-1)) were obtained.

  2. Single-walled carbon nanotubes as an effective adsorbent in solid-phase microextraction of low level methyl tert-butyl ether, ethyl tert-butyl ether and methyl tert-amyl ether from human urine.

    Science.gov (United States)

    Rastkari, Noushin; Ahmadkhaniha, Reza; Yunesian, Masud

    2009-05-15

    Carbon nanotubes (CNTs) are a kind of new carbon-based nano-materials which have drawn great attention in many application fields. The potential single-walled carbon nanotubes (SWCNTs) as solid-phase microextraction (SPME) adsorbents for the preconcentration of environmental pollutants have been investigated in recent years. The goal of this work was to investigate the feasibility of SWCNTs used as adsorbents for solid-phase microextraction of methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE) and tert-amyl methyl ether (TAME) in human urine. SWCNTs were attached onto a stainless steel wire through organic binder. Potential factors affecting the extraction efficiency were optimized, including extraction time, extraction temperature, desorption time, desorption temperature, and salinity. The developed method showed good performance according to the ICH performance criteria for bioanalytical methods. The calibration curves of the ethers were linear (r(2)>or=0.992) in the range from 10 to 5000 ng L(-1). The limits of detection at a signal-to-noise (S/N) ratio of 3 were 10 ng L(-1) for all the analytes. In addition, compared with the commercial carboxen/polydimethylsiloxane (CAR/PDMS) fiber, the SWCNT fiber showed better thermal stability (over 350 degrees C) and longer life span (over 150 times). The developed method was applied successfully to determine trace level of the ethers in urine of 10 healthy male volunteers.

  3. Catalytic Synthesis of Tert-Butyl Acetate by Nd2O3/Al2O3-Nd2O3/ZnO

    Institute of Scientific and Technical Information of China (English)

    Wang Yajun; Han Limin; A Shan

    2007-01-01

    Nd2O3 was used to support Al2O3 and ZnO to prepare a supported solid base catalyst and investigate the effect of catalyst and reaction conditions on the synthesis of tert-butyl acetate. The composited oxide of Nd2O3/Al2O3-Nd2O3/ZnO exhibited excellent catalytic activity for the synthsis of tert-butyl acetate. The molar ratio of tert-butanol to acetic anhydride is 3:1, the catalyst in total amount of reactant nearly 0.5%, and reaction time 6 h. With the above conditions, yield of the reaction could reach to 65%. The structure of product were verified by the FT-IR, Element analysis, and MS, which proved that the product was tert-butyl acetate.

  4. The Emulsion Polymerization of Each of Vinyl Acetate and Butyl Acrylate Monomers Using bis (2-ethylhexyl Maleate for Improving the Physicomechanical Properties of Paints and Adhesive Films

    Directory of Open Access Journals (Sweden)

    K. A. Shaffei

    2009-01-01

    Full Text Available Improving the water sensitivity of polyvinyl acetate PVAc films as well as pressure sensitivity, adhesion and washability of polybutyl acrylate were achieved by using bis (2-ethylhexyl maleate (BEHM. The emulsion polymerization kinetics of vinyl acetate and butyl acrylate in presence of BEHM was studied. The order of the polymerization reaction with respect to the BEHM in presence of each of vinyl acetate and butyl acrylate was studied. The physicomechanical properties of the polyvinyl acetate films and vinyl acetate-butyl acrylate copolymer films were studied in presence of BEHM and the obtained results were matched with those prepared in the presence of pluronic F 108 and showed superior values. The obtained mean average molecular weights were found to be smaller in presence of BEHM assuring the presence of chain transfer reaction.

  5. Thermolytic 4-methylthio-1-butyl group for phosphate/thiophosphate protection in solid-phase synthesis of DNA oligonucleotides.

    Science.gov (United States)

    Cieślak, Jacek; Grajkowski, Andrzej; Livengood, Victor; Beaucage, Serge L

    2004-04-02

    The thermolabile 4-methylthio-1-butyl phosphate/thiophosphate protecting group for DNA oligonucleotides has been investigated for its potential application to a "heat-driven" process for either oligonucleotide synthesis on diagnostic microarrays or, oppositely, to the large-scale preparation of therapeutic oligonucleotides. The preparation of phosphoramidites 10a-d is straightforward, and the incorporation of these amidites into oligonucleotides via solid-phase techniques proceeds as efficiently as that achieved with 2-cyanoethyl deoxyribonucleoside phosphoramidites. The versatility of the 4-methylthio-1-butyl phosphate/thiophosphate protecting group is exemplified by its facile removal from oligonucleotides upon heating for 30 min at 55 degrees C in an aqueous buffer under neutral conditions or within 2 h at 55 degrees C in concentrated NH(4)OH. The deprotection reaction occurs through an intramolecular cyclodeesterification mechanism leading to the formation of sulfonium salt 18. When mixed with deoxyribonucleosides and N-protected 2'-deoxyribonucleosides or with a model phosphorothioate diester under conditions approximating those of large-scale (>50 mmol) oligonucleotide deprotection reactions, the salt 18 did not significantly alter DNA nucleobases or desulfurize the phosphorothioate diester model to an appreciable extent.

  6. Experimental determination and prediction of phase behavior for 1-butyl-3-methylimidazolium nonafluorobutyl sulfonate and carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Soon Kang; Park, YoonKook [Hongik University, Sejong (Korea, Republic of); Pore, Dattaprasad Marutrao [Shivaji University, Kolhapur (India)

    2014-09-15

    The vapor-liquid equilibrium of the binary system CO{sub 2}+1-butyl-3-methylimidazolium nonafluorobutyl sulfonate ([BMIM][NfO]) was measured over a temperature range of 298.2-323.2 K at intervals of 5.0 K for CO{sub 2} mole fraction ranging from 0.137 to 0.900 using a high-pressure variable-volume view cell. The Peng-Robinson equation of state was then applied with two-parameter mixing rules over the same range and the results compared with the experimentally obtained data. Increasing the alkyl chain length in perfluorinated sulfonate from methyl to butyl markedly increased the CO{sub 2} solubility. To investigate the effect of the number of fluorine atoms in the anion on the phase behavior of imidazolium based ionic liquid, these experimental results were then compared with those reported in previous experimental studies of 1-alkyl-3-methylimidazolium cations and with modeling data. It looks likely that both the number of fluorine atoms in the anion and the presence of S=O groups play an important role in designing CO{sub 2}-philic molecules.

  7. Butylated Hydroxyanisole Blocks the Occurrence of Tumor Associated Macrophages in Tobacco Smoke Carcinogen-Induced Lung Tumorigenesis

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yan; Choksi, Swati; Liu, Zheng-Gang, E-mail: zgliu@helix.nih.gov [Cell and Cancer Biology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892 (United States)

    2013-12-04

    Tumor-associated macrophages (TAMs) promote tumorigenesis because of their proangiogenic and immune-suppressive functions. Here, we report that butylated hydroxyanisole (BHA) blocks occurrence of tumor associated macrophages (TAMs) in tobacco smoke carcinogen-induced lung tumorigenesis. Continuous administration of butylated hydroxyanisole (BHA), a ROS inhibitor, before or after NNK treatment significantly blocked tumor development, although less effectively when BHA is administered after NNK treatment. Strikingly, BHA abolished the occurrence of F4/80{sup +} macrophages with similar efficiency no matter whether it was administered before or after NNK treatment. Detection of cells from bronchioalveolar lavage fluid (BALF) confirmed that BHA markedly inhibited the accumulation of macrophages while slightly reducing the number of lymphocytes that were induced by NNK. Immunohistological staining showed that BHA specifically abolished the occurrence of CD206{sup +} TAMs when it was administered before or after NNK treatment. Western blot analysis of TAMs markers, arginase I and Ym-1, showed that BHA blocked NNK-induced TAMs accumulation. Our study clearly demonstrated that inhibiting the occurrence of TAMs by BHA contributes to the inhibition of tobacco smoke carcinogen-induced tumorigenesis, suggesting ROS inhibitors may serve as a therapeutic target for treating smoke-induced lung cancer.

  8. Biodegradation of methyl tert-butyl ether by cometabolism with hexane in biofilters inoculated with Pseudomonas aeruginosa.

    Science.gov (United States)

    Salazar, Margarita; Morales, Marcia; Revah, Sergio

    2012-01-01

    Biodegradation of methyl tert-butyl ether (MTBE) vapors by cometabolism with gaseous hexane (n-hexane > 95%) was investigated using Pseudomonas aeruginosa utilizing short chain aliphatic hydrocarbon (C(5)-C(8)). Kinetic batch experiments showed that MTBE was degraded even when hexane was completely exhausted with a cometabolic coefficient of 1.06 ± 0.16 mg MTBE mg hexane(-1). Intermediate tert-butyl alcohol (TBA) accumulation was observed followed by its gradual consumption. A maximum MTBE elimination capacity (EC(MAX)) of 35 g m(-3) h(-1) and removal efficiency (RE) of 70% were attained in mineral medium amended biofilters having an empty bed residence time (EBRT) of 1 min. For these experimental conditions, a maximum hexane EC of approximately 60 g m(-3) h(-1) was obtained at a load of 75 g m(-3) h(-1). Experiments under transient conditions revealed a competitive substrate interaction between MTBE and hexane. Biomass densities between 5.8 and 12.6 g L(biofilter) (-1) were obtained. Nevertheless, production of biopolymers caused non-uniform distribution flow rates that reduced the performance. Residence time distribution profiles showed an intermediate dispersion flow rate with a dispersion coefficient of 0.8 cm(2) s(-1).

  9. Investigation of emissions characteristics of secondary butyl alcohol-gasoline blends in a port fuel injection spark ignition engine

    Directory of Open Access Journals (Sweden)

    Yusri I.M.

    2017-01-01

    Full Text Available Exhaust emissions especially from light duty gasoline engine are a major contributor to air pollution due to the large number of vehicles on the road. The purpose of this study is to experimentally analyse the exhaust pollutant emissions of a four-stroke port fuel spark ignition engines operating using secondary butyl alcohol–gasoline blends by percentage volume of 5% (GBu5, 10% (GBu10 and 15% (GBu15 of secondary butyl- alcohol (2-butanol additives in gasoline fuels at 50% of wide throttle open. The exhaust emissions characteristics of the engine using blended fuels was compared to the exhaust emissions of the engine with gasoline fuels (G100 as a reference fuels. Exhaust emissions analysis results show that all of the blended fuels produced lower CO by 8.6%, 11.6% and 24.8% for GBu5, GBu10 and GBu15 respectively from 2500 to 4000 RPM, while for HC, both GBu10 and GBu15 were lower than that G100 fuels at all engine speeds. In general, when the engine was operated using blended fuels, the engine produced lower CO and HC, but higher CO2.

  10. Study of interaction of butyl p-hydroxybenzoate with human serum albumin by molecular modeling and multi-spectroscopic method

    Energy Technology Data Exchange (ETDEWEB)

    Wang Qin, E-mail: wqing07@lzu.c [Department of Chemistry, Lanzhou University, Lanzhou 730000 (China); Zhang Yaheng, E-mail: zhangyah04@lzu.c [Department of Chemistry, Lanzhou University, Lanzhou 730000 (China); Sun Huijun, E-mail: sun.hui.jun-04@163.co [Department of Chemistry, Lanzhou University, Lanzhou 730000 (China); Chen Hongli, E-mail: hlchen@lzu.edu.c [Department of Chemistry, Lanzhou University, Lanzhou 730000 (China); Chen Xingguo, E-mail: chenxg@lzu.edu.c [Department of Chemistry, Lanzhou University, Lanzhou 730000 (China)

    2011-02-15

    Study of the interaction between butyl p-hydroxybenzoate (butoben) and human serum albumin (HSA) has been performed by molecular modeling and multi-spectroscopic method. The interaction mechanism was predicted through molecular modeling first, then the binding parameters were confirmed using a series of spectroscopic methods, including fluorescence spectroscopy, UV-visible absorbance spectroscopy, circular dichroism (CD) spectroscopy and Fourier transform infrared (FT-IR) spectroscopy. The thermodynamic parameters of the reaction, standard enthalpy {Delta}H{sup 0} and entropy {Delta}S{sup 0}, have been calculated to be -29.52 kJ mol{sup -1} and -24.23 J mol{sup -1} K{sup -1}, respectively, according to the Van't Hoff equation, which suggests the van der Waals force and hydrogen bonds are the predominant intermolecular forces in stabilizing the butoben-HSA complex. Results obtained by spectroscopic methods are consistent with that of the molecular modeling study. In addition, alteration of secondary structure of HSA in the presence of butoben was evaluated using the data obtained from UV-visible absorbance, CD and FT-IR spectroscopies. - Research highlights: The interaction between butyl p-hydroxybenzoate with HSA has been investigated for the first time. Molecular modeling study can provide theoretical direction for experimental design. Multi-spectroscopic method can provide the binding parameters and thermodynamic parameters. These results are important for food safety and human health when using parabens as a preservative.

  11. Healing of periodontal flaps when closed with silk sutures and N-butyl cyanoacrylate: A clinical and histological study

    Directory of Open Access Journals (Sweden)

    Kulkarni Sudhindra

    2007-01-01

    Full Text Available Background: The closure of the periodontal flaps post-surgery is a necessity for attainment of a primary union between the flap margins and the establishment of a healthy dentogingival junction. N-butyl cyanoacrylate is a tissue adhesive, which can be used for the closure of the incised wounds to overcome the problems associated with conventional suture materials like silk. Objective: The present study was carried out to assess the healing of the periodontal flaps when closed with the conventional silk sutures and N-butyl cyanoacrylate. Materials and Methods: The study was carried out on 24 patients who needed flap surgical procedure for pocket therapy. Results: It was found that healing with the cyanoacrylate is associated with less amount of inflammation during the first week when compared with silk. However, over a period of 21 days to 6 weeks, the sites treated with both the materials showed similar healing patterns. Conclusion: It can be concluded that cyanoacrylate aids in early initial healing.

  12. Enhanced cometabolic degradation of methyl tert-butyl ether by a Pseudomonas sp. strain grown on n-pentane

    Science.gov (United States)

    Li, S. S.; Wang, S.; Yan, W.

    2016-08-01

    When methyl tert-butyl ether (MTBE) is added as oxygenates it increases the octane number and decreases the release of nitric oxide from the incomplete combustion of reformulated gasoline. The extensive use of MTBE allowed it to be detectable as a pollutant in both ground-level and underground water worldwide. The present study focuses on the isolation and characterization of MTB-degrading microorganisms by cometabolism based on the results of growth on different carbon sources. It also focuses on the kinetic analysis and the continuous degradation of MTBE. A bacterial strain WL1 that can grow on both n-alkanes (C5-C8) and aromatics was isolated and named Pseudomonas sp. WL1 according to the 16S rDNA sequencing analysis. Strain WL1 could cometabolically degrade MTBE in the presence of n-alkanes with a desirable degradation rate. Diverse n-alkanes with different lengths of carbon chains showed significant influence on the degradation rate of MTBE and accumulation of tert-butyl alcohol (TBA). When strain WL1 cometabolically degraded MTBE in the presence of n-pentane, higher MTBE-degrading rate and lower TBA-accumulation were observed (Vmax = 38.1 nmol/min/mgprotei, Ks = 6.8 mmol/L). In the continuous degrading experiment, the removal efficiency of MTBE by Pseudomonas sp. WL1 did not show any obvious decrease after five subsequent additions.

  13. SYNTHESIS OF POLYACRYLAMIDE WITH PENDANT POLY(BUTYL ACRYLATE) CHAINS USING THE MACROMER TECHNIQUE AND STUDIES ON THEIR PROPERTIES

    Institute of Scientific and Technical Information of China (English)

    Hong-quan Xie; Gui-ying Liao; Yu Gao

    2004-01-01

    An amphiphilic graft polymer, (PAM-g-PBA), polyacrylamide (PAM) having poly(n-butyl acrylate) (PBA) side chains, was obtained by radical copolymerization of acrylamide with PBA macromer in solution. The macromer was synthesized by free radical polymerization of butyl acrylate in the presence of different amounts of thioglycolic acid as the chain transfer agent, followed by termination with glycidyl methacrylate. The reactivity ratio and effects of copolymerization conditions on the conversion of macromer or grafting efficiency were studied. The crude products were purified by extraction with toluene and water successively. Thc purified graft copolymer was characterized by IR, DSC and TEM. PAM-g-PBA can bring about microphase separation and exhibits good emulsifying properties and water absorbency. PAM-g-PBA exhibits a very good compatibilizing effect on the acrylic rubber/poly(vinyl chloride) blends. 2%-3% of the graft copolymer is enough for enhancing the tensile strength of the blends. The tensile strength of the blends is more than twice that without the compatibilizer. DSC and SEM demonstrated the enhancement of compatibility in the presence of the graft copolymer.

  14. Preparation of l-butyl-3-methylimidazolium dodecatungstophosphate and its. catalytic performance for esterification of ethanol and acetic acid

    Institute of Scientific and Technical Information of China (English)

    Jiehua SHI; Gao PAN

    2009-01-01

    l-Butyl-3-methylimidazolium dodecatungstophosphate catalyst ([bmim]3PW12040) with high water tolerance was prepared from l-butyl-3-methylimidazolium bromide ([bmim]Br) and phosphotungstic acid (H3PW12O40). The catalyst was characterized by means of Fourier transform infrared spectroscopy, thermogravi-metry-differential scanning calorimetry, n-BuNH2 poten-tiometric titration, elemental analysis and so on. Its catalytic activity for esterification of ethanol and acetic acid to ethyl acetate was measured. The results show that there were three crystal-water molecules in the [bmim]3PW12040 catalyst, and it preserved the primary Keggin structure and acid strength of H3PW12O40. The acid amount of [bmim]3PW12O40 catalyst was less than that of H3PW12O40. The [bmim]3PW12O40 catalyst exhibited higher catalytic activity and reusability in the esterification of ethanol and acetic acid to ethyl acetate.

  15. Synthesis and pharmacological evaluation of 1-alkyl-N-[2-ethyl-2-(4-fluorophenyl)butyl]piperidine-4-carboxamide derivatives as novel antihypertensive agents.

    Science.gov (United States)

    Watanuki, Susumu; Matsuura, Keisuke; Tomura, Yuichi; Okada, Minoru; Okazaki, Toshio; Ohta, Mitsuaki; Tsukamoto, Shin-Ichi

    2011-09-15

    We synthesized and evaluated inhibitory activity against T-type Ca(2+) channels for a series of 1-alkyl-N-[2-ethyl-2-(4-fluorophenyl)butyl]piperidine-4-carboxamide derivatives. Structure-activity relationship studies have revealed that dialkyl substituents at the benzylic position play an important role in increasing inhibitory activity. Oral administration of N-[2-ethyl-2-(4-fluorophenyl)butyl]-1-(2-phenylethyl)piperidine-4-carboxamide (20d) lowered blood pressure in spontaneously hypertensive rats without inducing reflex tachycardia, which is often caused by traditional L-type Ca(2+) channel blockers.

  16. Dosimetric measurements of an n-butyl cyanoacrylate embolization material for arteriovenous malformations

    Energy Technology Data Exchange (ETDEWEB)

    Labby, Zacariah E., E-mail: zelabby@humonc.wisc.edu [Department of Human Oncology, University of Wisconsin–Madison, 600 Highland Avenue, Madison, Wisconsin 53792 (United States); Chaudhary, Neeraj [Division of Neurointerventional Radiology, Departments of Radiology and Neurosurgery, University of Michigan Hospital and Health Systems, 1500 East Medical Center Drive, Ann Arbor, Michigan 48109 (United States); Gemmete, Joseph J. [Division of Neurointerventional Radiology, Departments of Radiology, Neurosurgery, and Otolaryngology, University of Michigan Hospital and Health Systems, 1500 East Medical Center Drive, Ann Arbor, Michigan 48109 (United States); Pandey, Aditya S. [Department of Neurosurgery, University of Michigan Hospital and Health Systems, 1500 East Medical Center Drive, Ann Arbor, Michigan 48109 (United States); Roberts, Donald A. [Radiation Physics Division, Department of Radiation Oncology, University of Michigan Hospital and Health Systems, 1500 East Medical Center Drive, Ann Arbor, Michigan 48109 (United States)

    2015-04-15

    Purpose: The therapeutic regimen for cranial arteriovenous malformations often involves both stereotactic radiosurgery and endovascular embolization. Embolization agents may contain tantalum or other contrast agents to assist the neurointerventionalists, leading to concerns regarding the dosimetric effects of these agents. This study investigated dosimetric properties of n-butyl cyanoacrylate (n-BCA) plus lipiodol with and without tantalum powder. Methods: The embolization agents were provided cured from the manufacturer with and without added tantalum. Attenuation measurements were made for the samples and compared to the attenuation of a solid water substitute using a 6 MV photon beam. Effective linear attenuation coefficients (ELAC) were derived from attenuation measurements made using a portal imager and derived sample thickness maps projected in an identical geometry. Probable dosimetric errors for calculations in which the embolized regions are overridden with the properties of water were calculated using the ELAC values. Interface effects were investigated using a parallel plate ion chamber placed at set distances below fixed samples. Finally, Hounsfield units (HU) were measured using a stereotactic radiosurgery CT protocol, and more appropriate HU values were derived from the ELAC results and the CT scanner’s HU calibration curve. Results: The ELAC was 0.0516 ± 0.0063 cm{sup −1} and 0.0580 ± 0.0091 cm{sup −1} for n-BCA without and with tantalum, respectively, compared to 0.0487 ± 0.0009 cm{sup −1} for the water substitute. Dose calculations with the embolized region set to be water equivalent in the treatment planning system would result in errors of −0.29% and −0.93% per cm thickness of n-BCA without and with tantalum, respectively. Interface effects compared to water were small in magnitude and limited in distance for both embolization materials. CT values at 120 kVp were 2082 and 2358 HU for n-BCA without and with tantalum, respectively

  17. Radical Scavenging and Antimicrobial Activities of Methanol Extracts of Two Kinds of Formicary%两种蚂蚁巢甲醇提取物的自由基清除及抗菌活性研究

    Institute of Scientific and Technical Information of China (English)

    李建许; 徐学清; 杨海龙; 刘彤光; 赖仞

    2006-01-01

    Methanol extracts of two kinds of formicary were investigated for their free radical scavenging activities, total phenolic content, reduction power and antimicrobial activities. Both of them showed no toxic effect on mice at the testing dose of 10 mg/kg (p.o). The 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging test showed that both of the formicary extracts were potent radical scavengers and their scavenging activities were dose-dependent. Furthermore, at higher concentrations (5~10 mg/ml) both of them exhibited significantly higher DPPH scavenging activity than butylated hydroxytoluene (BHT). Total phenolic content and reducing power were determined using the Folin-Ciocalteu and the potassium ferricyanide reduction methods, respectively. Statistical analysis indicated a close association between the antioxidant potency and total phenolic content, and between the antioxidant potency and reducing power as well. Both methanol extracts presented antimicrobial activities on gram-negative and gram-positive bacteria. However, they were inactive on fungus.%对两种不同的蚂蚁窝进行甲醇提取,并对提取物进行了急性毒性、抗自由基,酚含量、还原能力和抗菌活性的检测.二苯基三硝基肼(1,1-diphenyl-2-picrylhydrazyl ,DPPH)自由基的清除能力的检测表明:两种蚂蚁窝甲醇提取物都具有显著的自由基清除能力,并呈现出剂量依赖性,而且,在高浓度时(5~10 mg·mL-1),它们的自由基清除能力甚至显著地高于二丁基羟基甲苯(butylated hydroxyl toluene,BHT).酚的含量和还原能力分别用福林酚试剂和铁氰化钾还原反应来测定,统计分析显示两种蚂蚁窝的抗氧化能力和其酚含量、还原能力都存在着正相关.两种蚂蚁窝甲醇提取物都具有抗革兰氏阴性菌和革兰氏阳性菌的活性,但它们却对真菌没有作用.

  18. Structure and Vibrational Spectra of Tert-butyl N-(2- bromocyclohex-2-enyl)-N-(2-furylmethyl)carbamate%Tert-butyl(N-(2-bromocyclohex-2-enyl)-N-(2-furylmethyl)carbamate的结构和振动光谱

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The molecular structure, conformational stability, and vibrational frequencies of tert-butyl N-(2-bromocyclohex-2-enyl)-N-(2-furylmethyl)carbamate (TBBFC) were investigated by utilizing the Hartree-Fock (HF) and density functional theory (DFT) ab initio calculations with 6-31G* and 6-31G* * basis sets. The optimized bond length and angle values obtained by HF method showed the best agreement with the experimental values. Comparison of the observed and calculated fundamental vibrational frequencies indicated that B3LYP was superior to the scaled HF approach for molecular problems. Optimal uniform scaling factors calculated for the title compound are 0.899/0.904,0.958/0.961, and 0.988/0.989 for HF, B3LYP, and BLYP (6-31G */6-31G* *), respectively.

  19. Microbial degradation and fate in the environment of methyl tert-butyl ether and related fuel oxygenates.

    Science.gov (United States)

    Fayolle, F; Vandecasteele, J P; Monot, F

    2001-08-01

    Oxygenates, mainly methyl tert-butyl ether (MTBE), are commonly added to gasoline to enhance octane index and improve combustion efficiency. Other oxygenates used as gasoline additives are ethers such as ethyl tert-butyl ether (ETBE), tert-amyl methyl ether (TAME), and alcohols such as tert-butyl alcohol (TBA). As a result of its wide use, MTBE has been detected, mainly in the USA, in groundwater and surface waters, and is a cause of concern because of its possible health effects and other undesirable consequences. MTBE is a water-soluble and mobile compound that generates long pollution plumes in aquifers impacted by gasoline releases from leaking tanks. Field observations concur in estimating that, because of recalcitrance to biodegradation, natural attenuation is slow (half-life of at least 2 years). However, quite significant advances have been made in recent years concerning the microbiology of the degradation of MTBE and other oxygenated gasoline additives. The recalcitrance of these compounds results from the presence in their structure of an ether bond and of a tertiary carbon structure. For the most part, only aerobic microbial degradation systems have been reported so far. Consortia capable of mineralizing MTBE have been selected. Multiple instances of the cometabolism of MTBE with pure strains or with microflorae, growing on n-alkanes, isoalkanes, cyclohexane or ethers (diethyl ether, ETBE), have been described. MTBE was converted into TBA in all cases and was sometimes further degraded, but it was not used as a carbon source by the pure strains. However, mineralization of MTBE and TBA by several pure bacterial strains using these compounds as sole carbon and energy source has recently been reported. The pathways of metabolism of MTBE involve the initial attack by a monooxygenase. In several cases, the enzyme was characterized as a cytochrome P-450. After oxygenation, the release of a C -unit as formaldehyde or formate leads to the production of TBA

  20. Determination of low level methyl tert-butyl ether, ethyl tert-butyl ether and methyl tert-amyl ether in human urine by HS-SPME gas chromatography/mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Scibetta, Licia [Department of Occupational and Environmental Medicine, University of Milano and Fondazione IRCCS Ospedale Maggiore Policlinico, Mangiagalli e Regina Elena, Via S. Barnaba, 8-20122 Milan (Italy); Campo, Laura [Department of Occupational and Environmental Medicine, University of Milano and Fondazione IRCCS Ospedale Maggiore Policlinico, Mangiagalli e Regina Elena, Via S. Barnaba, 8-20122 Milan (Italy); Mercadante, Rosa [Department of Occupational and Environmental Medicine, University of Milano and Fondazione IRCCS Ospedale Maggiore Policlinico, Mangiagalli e Regina Elena, Via S. Barnaba, 8-20122 Milan (Italy); Foa, Vito [Department of Occupational and Environmental Medicine, University of Milano and Fondazione IRCCS Ospedale Maggiore Policlinico, Mangiagalli e Regina Elena, Via S. Barnaba, 8-20122 Milan (Italy); Fustinoni, Silvia [Department of Occupational and Environmental Medicine, University of Milano and Fondazione IRCCS Ospedale Maggiore Policlinico, Mangiagalli e Regina Elena, Via S. Barnaba, 8-20122 Milan (Italy)]. E-mail: silvia.fustinoni@unimi.it

    2007-01-02

    Methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE) and tert-amyl methyl ether (TAME) are oxygenated compounds added to gasoline to enhance octane rating and to improve combustion. They may be found as pollutants of living and working environments. In this work a robotized method for the quantification of low level MTBE, ETBE and TAME in human urine was developed and validated. The analytes were sampled in the headspace of urine by SPME in the presence of MTBE-d12 as internal standard. Different fibers were compared for their linearity and extraction efficiency: carboxen/polydimethylsiloxane, polydimethylsiloxane/divinylbenzene, and polydimethylsiloxane. The first, although highly efficient, was discarded due to deviation of linearity for competitive displacement, and the polydimethylsiloxane/divinylbenzene fiber was chosen instead. The analysis was performed by GC/MS operating in the electron impact mode. The method is very specific, with range of linearity 30-4600 ng L{sup -1}, within- and between-run precision, as coefficient of variation, <22 and <16%, accuracy within 20% the theoretical level, and limit of detection of 6 ng L{sup -1} for all the analytes. The influence of the matrix on the quantification of these ethers was evaluated analysing the specimens of seven traffic policemen exposed to autovehicular emissions: using the calibration curve and the method of standard additions comparable levels of MTBE (68-528 ng L{sup -1}), ETBE (<6 ng L{sup -1}), and TAME (<6 ng L{sup -1}) were obtained.

  1. Solubilities of carbon dioxide and oxygen in the ionic liquids methyl trioctyl ammonium bis(trifluoromethylsulfonyl)imide, 1-butyl-3-methyl imidazolium bis(trifluoromethylsulfonyl)imide, and 1-butyl-3-methyl imidazolium methyl sulfate.

    Science.gov (United States)

    Bahadur, Indra; Osman, Khalid; Coquelet, Christophe; Naidoo, Paramespri; Ramjugernath, Deresh

    2015-01-29

    Ionic liquids (ILs) are being considered as solvents for gas absorption processes as they have the potential, in general, for improved efficiency of gas separations, as well as lower capital and operating costs compared to current commercial processes. In this study the solvent properties of ILs are investigated for use in the absorption of carbon dioxide (CO2) and oxygen (O2). The absorption of these gases in ILs was measured in the temperature range 303.15-333.15 K and at pressures up to 1.5 MPa by gravimetric analysis. The ILs used were methyl trioctyl ammonium bis (trifluoromethylsulfonyl) imide ([MOA][Tf2N]), 1-butyl-3-methyl imidazolium bis (trifluoromethylsulfonyl) imide ([BMIM][Tf2N]), and 1-butyl-3-methyl imidazolium methyl sulfate ([BMIM][MeSO4]). The measurement technique employed in this study is fast and accurate, and requires small quantities of solvent. The results indicated that absorption of both gases increased with a decrease in operating temperature and an increase in pressure. [MOA][Tf2N] had the highest CO2 and O2 solubility. [BMIM][Tf2N] was determined to have the highest selectivity for CO2 absorption. [BMIM][MeSO4] achieved the lowest CO2 absorption with a moderate O2 absorption, revealing this IL to be the least desirable for CO2 and O2 absorption. Calculation of Henry's law constants for all systems confirmed the deductions made from absorption data analysis. Calculation of enthalpy and entropy of absorption for each system revealed CO2 absorption in [MOA][Tf2N] to be the least sensitive to temperature increases. The absorption data was modeled using the generic Redlich-Kwong cubic equation of state (RK-EOS) coupled with a group contribution method.

  2. Separation of Ephedrines Using 1-Butyl-3-methylimidazolium-tetrafluoroborate Ionic Liquids as Eluent in High-performance Liquid Chromatography (HPLC)

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A simple, effective HPLC method for separation of ephedrines was achieved by using1-butyl-3-methylimidazolium-tetrafluoroborate ionic liquid solution (0.1% v/v) as eluent at pH 3.0.The involved mechanism may be due to that the imidazolium cations can effectively shield thesilanol groups of alkylsilica surface, thereby decreasing band tailing and increasing the separationefficiency.

  3. 1-Butyl-3-methylimidazolium Hydrogen Sulfate [bmim]HSO4: An Efficient Reusable Acidic Ionic Liquid for the Formylation of Alcohols

    Institute of Scientific and Technical Information of China (English)

    NIKNAM Khodabakhsh; ZOLFIGOL Mohammad Ali; SABERI Dariush; KHONBAZI Mahdi

    2009-01-01

    1-Butyl-3-methylimidazolium hydrogen sulfate [bmim]HSO4 as an acidic ionic liquid was prepared and used as a catalyst for the formylation of alcohols with ethyl formate at room temperature with good to excellent yields.A good selectivity was observed for the formylation of primary alcohols in the presence of tertiary alcohols.

  4. Ionic liquid 1-butyl-3-methylimidazolium bromide ([bmim]Br: a green and neutral reaction media for the efficient, catalyst-free synthesis of quinoxaline derivatives

    Directory of Open Access Journals (Sweden)

    MAASOOMEH KHEDRI

    2010-10-01

    Full Text Available Quinoxaline derivatives were produced in excellent yields and short reaction times via the condensation of 1,2-diamines with 1,2-diketones in the neutral ionic liquid 1-butyl-3-methylimidazolium bromide ([bmim]Br under catalyst-free and microwave irradiation conditions.

  5. Intra-arterial tert-Butyl-hydroperoxide infusion induces an exacerbated sensory response in the rat hind limb and is associated with an impaired tissue oxygen uptake.

    NARCIS (Netherlands)

    Tan, E.C.T.H.; Goor, H. van; Bahrami, S.; Kozlov, A.V.; Leixnering, M.; Redl, H.; Goris, R.J.A.

    2011-01-01

    The objective of this study was to investigate oxidative stress and oxygen extraction mechanisms in an animal model of continuous intra-arterial infusion of a free radical donor and in an in vitro model using isolated mitochondria. tert-Butyl-hydroperoxide (tert-BuOOH, 25 mM) was infused for 24 h in

  6. Isomerization of 4-Amino-6-tert-butyl-3-methylthio-1, 2,4-triazin-5 (4H)-one with Base

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Isomerizaton of 4-amino-6-tert-butyl-3-methylthio-1, 2, 4-triazin-5 (4H)-one in the presence of base is described. Mechanism of this rearrangement reaction involving four-member ring intermediate formation has been proposed.

  7. X-Ray Structure of 8-Quinolinolato Lanthanide Complex:(8-Quinolinolato) bis (2,6-di-tert-butyl-4-methylphenoxo) samarium

    Institute of Scientific and Technical Information of China (English)

    YUAN,Fu-Gen(袁福根); LIU,Qing-Sheng(刘青生); WENG,Lin-Hong(翁林红)

    2002-01-01

    The heteroleptic (8-quinolinolato)bis(2,6-di-tert-butyl-4-methylphenoxo) samarium complex was synthesized and characterized by elemental analysis, IR spectrun and X-ray diffraction analysis. The complex is a five-coordinate dimer. Each 8-quinolinolato oxygen atom links two samarium atoms as a bridge and the Sm-N bond is a typical donor bond.

  8. Systemic uptake of diethyl phthalate, dibutyl phthalate, and butyl paraben following whole-body topical application and reproductive and thyroid hormone levels in humans

    DEFF Research Database (Denmark)

    Janjua, Nadeem Rezaq; Mortensen, Gerda Krogh; Andersson, Anna-Maria

    2007-01-01

    In vitro and animal studies have reported endocrine-disrupting activity of chemicals used commonly as additives in cosmetics and skin care products. We investigated whether diethyl phthalate (DEP), dibutyl phthalate (DBP), and butyl paraben (BP) were systemically absorbed and influenced endogenous...

  9. 40 CFR 721.1730 - Poly(oxy-1,2-ethanediyl), α-butyl-ω-hydroxy, ester with boric acid (H3BO3).

    Science.gov (United States)

    2010-07-01

    ...-hydroxy, ester with boric acid (H3BO3). 721.1730 Section 721.1730 Protection of Environment ENVIRONMENTAL..., ester with boric acid (H3BO3). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as poly(oxy-1,2-ethanediyl), α-butyl-ω-hydroxy, ester with...

  10. URINARY AND AMNIOTIC FLUID LEVELS OF PHTHALATE MONOESTERS IN RATS AFTER THE ORAL ADMINISTRATION OF DI(2-ETHYLHEXYL) PHTHALATE AND DI-N-BUTYL PHTHALATE

    Science.gov (United States)

    Two studies were designed to examine amniotic fluid and maternal urine concentrations of the di(2-ethylhexyl) phthalate (DEHP) metabolite mono(2-ethylhexyl) phthalate (MEHP) and the di-n-butyl phthalate (DBP) metabolite monobutyl phthalate (MBP) after administration of DEHP and D...

  11. Second harmonic generation at the interface of copper tetra-tert-butyl phthalocyanine Langmuir-Blodgett film/metal

    Institute of Scientific and Technical Information of China (English)

    程晓曼; 姚素薇; 李成全; 间中孝彰; 岩本光正

    2003-01-01

    Optical second harmonic generation (SHG) from the copper tetra-tert-butyl phthalocyanine (CuttbPc) Langmuir-Blodgett (LB) film deposited on a metal-coated glass slide substrate has been investigated. It is considered that the symmetry of the CuttbPc molecule may be broken by the space charge-induced electric field (SCIEF) due to the exchanged charges at the CuttbPc LB film/metal interface. A four-layer model is used to explain the nonlinear optical process in the CuttbPc LB film. The thickness dependence, polarized and incident angle dependence of SHG signal from CuttbPc LB films are calculated. The results of calculation show a good agreement with the experimental data. It is shown that electrostatic phenomena at the interface is correlated closely with SHG signal, and the SHG measurement is also a helpful tool for the detection of the space charge field at the interface.

  12. Production and market analysis of butyl rubber%丁基橡胶生产及市场分析

    Institute of Scientific and Technical Information of China (English)

    刘隽姝; 王东巍; 吴玉峰; 王启弘

    2012-01-01

    Butyl rubber(IIR) is an unreplacbale rubber of the tyre with or without inner tube due to its excellent airtightness, watertightness, weathering resistance and chemical anticorrosivity. This paper inroduces production actuality of IIR, summarizes production capacity, import/export and appearance consumption of IRR,and analyzes and predicts market trend. Furthermore, this paper gives some advices on domestic IIR industry development.%介绍了国内外丁基橡胶(IIR)的生产现状,总结了IIR的产能、进出口量和表观消费量,并对国内IIR的市场发展趋势进行了分析及预测.此外,还对国内IIR行业的发展提出了几点建议.

  13. When does the fluazifop-P-butyl degradate, TFMP, leach through an agricultural loamy soil to groundwater?

    DEFF Research Database (Denmark)

    Vendelboe, Anders Lindblad; Norgaard, Trine; Olsen, Preben;

    2016-01-01

    that pesticide degradates like TFMP, often being more soluble than the pesticide, have a relatively high leaching potential especially associated with heavy precipitation events shortly after the application. Hence, such pesticide degradates should like in Denmark be considered “relevant” meaning that the EU...... value for drinking water applies to them, having its leaching potential regulatory assessed based on high quality estimations of their persistence, and be exposed to an assessment of the risk to consumers of drinking contaminated groundwater.......In intensely cultivated regions, it is crucial to have knowledge of the leaching potential related to pesticides in agricultural production. This is especially true in countries, like Denmark, that base its drinking water supply on untreated groundwater. Since fluazifop-P-butyl (FPB) is applied...

  14. A comparative study of biodiesel production using methanol, ethanol, and tert-butyl methyl ether (MTBE) under supercritical conditions.

    Science.gov (United States)

    Farobie, Obie; Matsumura, Yukihiko

    2015-09-01

    In this study, biodiesel production under supercritical conditions among methanol, ethanol, and tert-butyl methyl ether (MTBE) was compared in order to elucidate the differences in their reaction behavior. A continuous reactor was employed, and experiments were conducted at various reaction temperatures (270-400 °C) and reaction times (3-30 min) and at a fixed pressure of 20 MPa and an oil-to-reactant molar ratio of 1:40. The results showed that under the same reaction conditions, the supercritical methanol method provided the highest yield of biodiesel. At 350 °C and 20 MPa, canola oil was completely converted to biodiesel after 10, 30, and 30 min in the case of - supercritical methanol, ethanol, and MTBE, respectively. The reaction kinetics of biodiesel production was also compared for supercritical methanol, ethanol, and MTBE.

  15. Energy analysis for the production of biodiesel in a spiral reactor using supercritical tert-butyl methyl ether (MTBE).

    Science.gov (United States)

    Farobie, Obie; Matsumura, Yukihiko

    2015-11-01

    In this study, energy analysis was conducted for the production of biodiesel in a spiral reactor using supercritical tert-butyl methyl ether (MTBE). This study aims to determine the net energy ratio (NER) and energy efficiency for the production of biodiesel using supercritical MTBE and to verify the effectiveness of the spiral reactor in terms of heat recovery efficiency. The analysis results revealed that the NER for this process was 0.92. Meanwhile, the energy efficiency was 0.98, indicating that the production of biodiesel in a spiral reactor using supercritical MTBE is an energy-efficient process. By comparing the energy supply required for biodiesel production between spiral and conventional reactors, the spiral reactor was more efficient than the conventional reactor.

  16. EFFECT OF 2—HYDROXYETHYL METHACRYLATE ON SEMIBATCH EMULSIFIER—FREE EMULSION COPOLYMERIZATION OF METHYL METHACRYLATE AND BUTYL ACRYLATE

    Institute of Scientific and Technical Information of China (English)

    GUOTianying; SONGMoudao; 等

    1999-01-01

    The semibatch emulsifier-free emulsion copolymerization of methyl methacrylate (MMA) and butyl acrylate(BA) in the presence of 2-hydroxyethyl methacrylate(HEMA) initiated by K2S2O8(PSP) was studied.The latex particles can maintain an appreciable stability during the emulsifier-free emulsion copolymerization of MMA and BA in the presence of HEMA.The average particle diameter increase with an increase of total solids content,HEMA content,PSP content,ionic strength of the system and monomer feed rate,and decrease with the monomer feed ration from 3/1 (MMA/BA:molar ration).to 1/3.The stability of this reaction system is improved by adding HEMA as nonionic comonomer,High solids content (50%) latex with monodisperse particle can be obtained using this process.

  17. Polymerization behaviour of butyl bis(hydroxymethyl)phosphine oxide: Phosphorus containing polyethers for Li-ion conductivity

    Indian Academy of Sciences (India)

    Heeralal Vignesh Babu; Billakanti Srinivas; Khevath Praveen Kumar Naik; Krishnamurthi Muralidharan

    2015-04-01

    Synthesis of phosphorus containing polyethers and their lithium-ion conductivities for the potential use as solid polymer electrolyte (SPE) in high-energy density lithium-ion batteries have been described. Co-polymerization of butyl bis(hydroxymethyl)phosphine oxide with three different dibromo monomers were carried out to produce three novel phosphorous containing polyethers (P1–P3). These polymers were obtained via nucleophilic substitution reactions and were characterized by 1H, 31P NMR spectral data and gel permeation chromatography. SPEs were prepared using polyethers (P1 and P2) with various amounts of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). The lithium-ion conductivity of SPE2 containing 40 wt% of LiTFSI was 2.1 × 10−5 S cm−1 at room temperature and 3.7 × 10−4 S cm−1 at 80°C.

  18. (2E-4-tert-Butyl-2-(4-methoxybenzylidene-3,4-dihydronaphthalen-1(2H-one

    Directory of Open Access Journals (Sweden)

    Mohamed Akhazzane

    2011-07-01

    Full Text Available In the title compound C22H24O2, the exocyclic C=C double bond is in an E configuration and the tert-butyl group is in an axial position on the cyclohexanone ring. The cyclohexanone ring in the dihydronaphthalene fused-ring system adopts a half-chair conformation in both independent two molecules in the asymetric unit. The benzene ring system is oriented angles of 43.97 (12 and 39.24 (12° with respect to the naphthyl ring system in the two independent molecules. In the crystal, molecules are linked via C—H...O hydrogen bonds and C—H...π interactions.

  19. Stereochemical dependence of 3JCH coupling constants in 2-substituted 4-t-butyl-cyclohexanone and their alcohol derivatives.

    Science.gov (United States)

    Favaro, Denize C; Ducati, Lucas C; dos Santos, Francisco P; Contreras, Rubén H; Tormena, Cláudio F

    2011-12-22

    Theoretical and experimental studies on (3)J(C2H6eq) NMR spin-spin coupling constants in both the 2-X-4-t-butyl-cyclohexanone (X = H, CH(3), F, Cl, and Br) and in their alcohol derivatives series are reported. Results thus found are rationalized in terms of the transmission of the Fermi contact contribution to such couplings. To this end, dependencies of (3)J(C2H6eq) couplings versus the C(2)-C(1)-C(6) angle are compared in both series for equatorial and axial X orientations. The main trend is described in terms of the rear lobes interaction. Besides, for X = halogen atom in equatorial orientation a rather strong interaction between oxygen and halogen lone pairs is observed, and its influence on (3)J(C2H6eq) couplings is discussed and rationalized in terms of different Fermi contact transmission pathways.

  20. Conformational analysis of cyclic sulphites. 2-Oxo 1,3,2-dioxathiane-4-spiro-4- tert-butyl-cyclohexanes

    Science.gov (United States)

    Cazaux, Louis; Koudsi, Yahia; Maroni, Pierre

    Three series of 4-spirosulphites, a new class of cyclic sulphites, were synthesized and five couples of diastereoisomers isolated. Their structural analysis, using 1H NMR coupling constants and SO stretching vibration as conformational probes, shows a large variety of ananchomeric chair forms and multicomponent equilibria for the cyclic sulphite moiety, the cyclohexane part of the molecule remaining in the chair form. Related to the occurrence of severe interactions involving the 5-methyl or 6- tert. butyl substituent, several twist forms were encountered, with 2,5-axis and isoclinal SO or 1,4-axis and axial or equatorial SO as a consequence of the weak free energy difference between chair and twist conformations in the cyclic sulphite series.

  1. Solubilities of benzene, toluene and diphenyl in the t-butyl alcohol + water mixtures and hydrophobic interaction

    Institute of Scientific and Technical Information of China (English)

    邹立壮; 杨冠英; 韩布兴; 刘瑞麟; 阎海科

    1999-01-01

    The solubilitices of benzene, toluene and diphenyl in mixed solvents of t-butyl alcohol (TBA) and water at 283.15, 288.15, 293.15 and 298.15 K have been determined by spectrophotometry. The mole fraction of TBA [x (TBA)] in the mixed solvent are 0.000, 0.010, 0.020, 0.030, 0.040, 0.045, 0.050, 0.060, 0.080 and 0.100, respectively. The standard Gibbs energies of solution of benzene, toluene and diphenyl in the mixed solvent have also been calculated based on the solubility data. The hydrophobic interactions (HI) for the pairs of benzene-benzene, methane-benzene and methane-methane in the mixed solvent were calculated and discussed.

  2. An ellagitannin, n-butyl gallate, two aryltetralin lignans, and an unprecedented diterpene ester from Pelargonium reniforme.

    Science.gov (United States)

    Latté, Klaus Peter; Kaloga, Maki; Schäfer, Andreas; Kolodziej, Herbert

    2008-02-01

    The structural diversity of the metabolic pool of Pelargonium reniforme was extended by the characterization of the 1C4-glucose based ellagitannin pelargoniin E, gallic acid n-butyl ester, (-)-4,4',9'-trihydroxy-3',5'-dimethoxy-2,7'-cyclolignan 9-O-beta-glucopyranoside and reniformin, a diterpene ester comprised of a diterpene acid with an uncommon -(CH2)(2)- bridging element linked to 2-(4-hydroxyphenyl)ethansulfonic acid. These metabolites were associated with the known (alpha,beta)-3,4-di-O-galloyl-glucopyranoside, 4,6-dihydroxy-2beta-glucopyranosyloxyacetophenone, 1-O-galloylglycerol, 6'-O-galloylsalidroside and (+)-isolariciresinol-9'-O-beta-glucopyranoside. All structures were established on the basis of spectroscopic methods.

  3. PREAPARATION OF CATIONIC LATEXES OF POLY(STYRENE-CO-BUTYL ACRYLATE) AND THEIR PROPERTIES EVOLUTION IN LATEX DILUTION

    Institute of Scientific and Technical Information of China (English)

    Dong Zou; Xiu-fen Li; Xiao-li Zhu; Xiang-zheng Kong

    2012-01-01

    Cationic latexes were prepared through emulsion copolymerization of styrene (St) and butyl acrylate (BA) with a cationic surfactant,cetyl trimethyl ammonium bromide (CTAB).Latex properties,including particle size,size distribution,ζ potential,surface tension and monomer conversion,were determined for latexes prepared with different CTAB amounts.Evolution of these properties during emulsion polymerization was followed in order to understand the mechanism of the particles formation.Results showed that both particle size and ζpotential were function of polymerization time and latex solids.Parallel emulsion polymerizations with cationic,anionic charged initiator and charge-free initiators were also carried out,the latex properties were determined at different polymerization time.All these results were attentively interpreted based on the mechanisms of emulsion polymerization,surfactant adsorption and latex particle stabilization.

  4. Kinetics of adsorption of di-n-butyl phthalate (DBP) by four different granule-activated carbons

    Institute of Scientific and Technical Information of China (English)

    Po keung TSANG; Zhanqiang FANG; Hui LIU; Xiaolei CHEN

    2008-01-01

    The kinetics of the adsorption of an endocrine disruptor,di,n,butyl phthalate (DBP),by four different granulated,activated carbons (GACs) is presented in this paper. Results showed that adsorption of DBP by the four GACs followed first,order kinetics and the adsorption constant of the four GAC was found to follow the order:nut shell>coconut shell>Coaly carbon 1.0>Coaly carbon 1.5. Batch adsorption studies were also conducted to investigate the effect of pH on the adsorption process. The optimum pH for the removal of DBP from aqueous solutions under the experimental conditions used in this work was found to be 5.0. The characterization of the carbon surfaces was conducted by using scanning electron microscopy (SEM). Furthermore,results from infrared spectroscopic (IR) studies showed that physical adsorption plays an important role in the adsorption of DBP by the four selected GACs.

  5. CO2 capture from binary mixture via forming hydrate with the help of tetra-n-butyl ammonium bromide

    Institute of Scientific and Technical Information of China (English)

    Shifeng Li; Shuanshi Fan; Jingqu Wang; Xuemei Lang; Deqing Liang

    2009-01-01

    Hydrate formation rate and separation effect on the capture of CO2 from binary mixture v/a forming hydrate with 5 wt% tetra-n-butyl ammonium bromide (TBAB) solution were studied.The results showed that the induction time was 5 min,and the hydrate formation process pressure of 7.30 MPa.The CO2 recovery was about 45% in the feed pressure range from 4.30 to 7.30 MPa.Under the feed pressure of 4.30 MPa,the maximum separation factor and CO2 concentration in hydrate phase were 7.3 and 38.2 tool%,respectively.The results demonstrated that TBAB accelerated hydrate formation and enriched CO2 in hydrate phase under the gentle condition.

  6. Effect of Oxygen on Surface Properties and Drug Release Behavior of Plasma Polymer of n-Butyl Methacrylate

    Institute of Scientific and Technical Information of China (English)

    Yuan YUAN; Chang Sheng LIU; Yuan ZHANG; Min YIN; Jie XU

    2005-01-01

    The effects of oxygen on the chemical structure, morphology, hydrophilicity and drug release behavior of radio-frequency plasma poly n- butyl methacrylate (PPBMA) thin film were carried out for the first time. ATR-FTIR and XPS showed that oxygen had little influence on the chemical structure and composition of PPBMAs, which did not agree with the thought that the presence of oxygen gas would increase the oxidized carbon functionalities in the plasma polymer.SEM and static contact angle measurement indicated that in case of deposition with oxygen, the smoothness and hydrophilicity of PPBMA were dramatically improved. The drug release behavior showed that drug release from the PPBMA coating without oxygen was biphasic patterns,while from PPBMA coating with oxygen was Higuchi release. These results were helpful for the design and tailoring of the PPBMA polymer film and other of plasma polymers film, but could provide a new idea for the drug release controlled form.

  7. UV absorption spectra, kinetics and mechanism for alkyl and alkyl peroxy radicals originating from t-butyl alcohol

    DEFF Research Database (Denmark)

    Langer, S.; Ljungström, E.; Sehested, J.

    1994-01-01

    Alkyl and alkyl peroxy radicals from 1-butyl alcohol (TBA), HOC (CH3)2CH2. and HOC(CH3)2CH2O2. have been studied in the ps phase at 298 K. Two techniques were used: pulse radiolysis UV absorption to measure the spectra and kinetics, and long path-length Fourier transform infrared spectroscopy (FTIR......) to identify and quantify the reaction products. Absorption cross sections were quantified over the wavelength range 220-320 nm. At 240 nm, sigma(HOC(CH3)2CH2) = (2.4 +/- 0.3) x 10(-18) and sigma(HOC(CH3)2CH2O2) = (3.4 +/- 0.5) X 10(-18) cm2 molecule-1 have been obtained. Observed rate constants for the self...

  8. Polymer electrolyte based on crosslinked poly(glycidyl methacrylate) and 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide

    Energy Technology Data Exchange (ETDEWEB)

    Fei, Beatrice Wong Chui; Hanifah, Sharina Abu; Ahmad, Azizan; Hassan, Nur Hasyareeda [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43000 Bangi, Selangor Darul Ehsan (Malaysia)

    2015-09-25

    Polymer electrolytes based on crosslinked poly(glycidyl methacrylate) as polymer host and 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (BmimTFSI) as incorporated salt were prepared by in-situ photopolymerization technique. The complexes with different mass ratio of glycidyl methacrylate (GMA) monomer to BmimTFSI were investigated. The ionic conductivity of the polymer electrolyte was increased and reach the highest value of 7.50 × 10{sup −4} S cm{sup −1} at the ratio of 3:7 (GMA: BmimTFSI). The interaction between the polymer host and ionic liquid was proved by Attenuated Total Reflectance-Fourier Transformation Infra-Red Spectroscopy (ATR-FTIR). Meanwhile, the X-ray diffraction analysis shows the amorphousity of the polymer electrolyte film increase with the ionic liquid ratio.

  9. Chitosan-graft-poly(n-butyl acrylate) copolymer: Synthesis and characterization of a natural/synthetic hybrid material.

    Science.gov (United States)

    Anbinder, Pablo; Macchi, Carlos; Amalvy, Javier; Somoza, Alberto

    2016-07-10

    Two chitosan polymers with different deacetylation degree and molecular weight were subjected to grafting reactions with the aim to enhance the properties of these bio-based materials. Specifically, n-butyl acrylate in different proportions was grafted onto two different deacetylation degree (DD%) chitosan using radical initiation in a surfactant free emulsion system. Infrared spectroscopy was used to confirm grafting and products grafting percentage and efficiency were evaluated against acrylate/chitosan ratio and DD%. Thermal and structural properties and the behavior against water of the raw and grafted biopolymers were studied using several experimental techniques: differential scanning calorimetry, transmission electron microscopy, dynamic light scattering, water swelling, contact angle and positron annihilation lifetime spectroscopy. The influence of the grafting process on the morphological and physicochemical properties of the prepared natural/synthetic hybrid materials is discussed.

  10. Comparison and Characterisation of Regenerated Chitosan from 1-Butyl-3-methylimidazolium Chloride and Chitosan from Crab Shells

    Directory of Open Access Journals (Sweden)

    Saniyat Islam

    2015-01-01

    Full Text Available Chitosan is a biopolymer derived from chitin which is naturally occurring in the exoskeleton of crustaceans. This paper reports dissolution and regeneration of chitosan by directly dissolving in an ionic liquid solvent, 1-butyl-3-methylimidazolium chloride (BMIMCl. This will provide an ideal platform to solubilise these kinds of polymers to achieve the dissolution. The current study dissolved chitosan from crab shell utilising BMIMCl as a solvent and characterised the resultant regenerated polymer. The regenerated chitosan showed increased hydrogen bonding when characterised by Fourier transform infrared (FTIR spectral analysis. In addition, the study also compared the characteristics of regenerated and generic chitosan. The regenerated chitosan was also evaluated for antimicrobial properties and showed to possess antibacterial features similar to the commercial grade. This method can be utilised in future for blending of polymers with chitosan in a dissolved phase.

  11. Comparison and Characterisation of Regenerated Chitosan from 1-Butyl-3-methylimidazolium Chloride and Chitosan from Crab Shells.

    Science.gov (United States)

    Islam, Saniyat; Arnold, Lyndon; Padhye, Rajiv

    2015-01-01

    Chitosan is a biopolymer derived from chitin which is naturally occurring in the exoskeleton of crustaceans. This paper reports dissolution and regeneration of chitosan by directly dissolving in an ionic liquid solvent, 1-butyl-3-methylimidazolium chloride (BMIMCl). This will provide an ideal platform to solubilise these kinds of polymers to achieve the dissolution. The current study dissolved chitosan from crab shell utilising BMIMCl as a solvent and characterised the resultant regenerated polymer. The regenerated chitosan showed increased hydrogen bonding when characterised by Fourier transform infrared (FTIR) spectral analysis. In addition, the study also compared the characteristics of regenerated and generic chitosan. The regenerated chitosan was also evaluated for antimicrobial properties and showed to possess antibacterial features similar to the commercial grade. This method can be utilised in future for blending of polymers with chitosan in a dissolved phase.

  12. Understanding the large solubility of lidocaine in 1-n-butyl-3-methylimidazolium based ionic liquids using molecular simulation

    Science.gov (United States)

    Ley, Ryan T.; Paluch, Andrew S.

    2016-02-01

    Room temperature ionic liquids have been proposed as replacement solvents in a wide range of industrial separation processes. Here, we focus on the use of ionic liquids as solvents for the pharmaceutical compound lidocaine. We show that the solubility of lidocaine in seven common 1-n-butyl-3-methylimidazolium based ionic liquids is greatly enhanced relative to water. The predicted solubility is greatest in [BMIM]+[CH3CO2]-, which we find results from favorable hydrogen bonding between the lidocaine amine hydrogen and the [CH3CO2]- oxygen, favorable electrostatic interactions between the lidocaine amide oxygen with the [BMIM]+ aromatic ring hydrogens, while lidocaine does not interfere with the association of [BMIM]+ with [CH3CO2]-. Additionally, by removing functional groups from the lidocaine scaffold while maintaining the important amide group, we found that as the van der Waals volume increases, solubility in [BMIM]+[CH3CO2]- relative to water increases.

  13. Structure-Dependent 4-Tert-Butyl Pyridine-Induced Band Bending at TiO2 Surfaces

    Directory of Open Access Journals (Sweden)

    Mats Göthelid

    2011-01-01

    Full Text Available The role of 4-tert butyl pyridine (4TBP adsorption on TiO2 surface band bending has been studied using photoelectron spectroscopy. Surface oxygen vacancies pin the Fermi level near the conduction band edge on rutile (110. 4TBP preferentially adsorbs in those vacancies and shift the Fermi level to lower binding energy in the band gap. This is done by transferring vacancy excess charge into the empty π∗ orbital in the pyridine ring. The anatase (100 surface contains much less oxygen vacancies although the surface is much rougher than the rutile (110. 4TBP adsorption does not have any significant effect on the surface band bending. Thus the positive role associated with 4TBP addition to solar cell electrolytes is suggested to protection against adsorption of other electrolyte components such as Li and I.

  14. Vibrational Spectroscopic Studies and Computational Study of 1,2-Diphenyl-4-n-Butyl-3,5-Pyrazolidinedione

    Directory of Open Access Journals (Sweden)

    C. Yohannan Panicker

    2011-01-01

    Full Text Available FT-IR and FT-Raman spectra of 1,2-diphenyl-4-n-Butyl-3,5-pyrazolidinedione (Phenylbutazone were recorded and analyzed. The vibrational wavenumbers were computed using HF/6-31G(d and B3LYP/6-31G(d basis sets and compared with experimental data. The first hyperpolarizability, infrared intensities and Raman activities are also reported. The geometrical parameters of the title compound obtained from theoretical calculations are in agreement with that of reported similar derivatives. The first hyperpolarizability is comparable with reported values of similar derivatives and is an attractive molecule for future applications in non-linear optics. The variation in C-N bond lengths suggests an extended π-electron delocalization over the pyrazolidinedione moiety which is responsible for the nonlinearity of the molecule.

  15. HALONICKEL 2,4-DI-t-BUTYL-6-(QUINOLIN-8-YLIMINOMETHYL)PHENOLATES:SYNTHESIS, CHARACTERIZATION AND ETHYLENE REACTIVITY

    Institute of Scientific and Technical Information of China (English)

    Qi-song Shi; Xiang Hao; Carl Redshaw; Wen-hua Sun

    2013-01-01

    A series of nickel halides bearing 2,4-di-t-butyl-6-(quinolin-8-yliminomethyl) phenolate ligands was synthesized and characterized by IR spectroscopy and elemental analysis.Molecular structures of C1 (R =H,X =Br) and C2 (R =H,X =Cl) were further confirmed by single-crystal X-ray crystallographic studies,and revealed a distorted square planar geometry at nickel.Upon activation with diethylaluminum chloride (Et2AlCl),all nickel pre-catalysts displayed good catalytic activity [up to 9.3 × 105 g mol-1(Ni) h-1] for ethylene oligomerization with major dimerization.In the presence of methylaluminoxane (MAO),the nickel complex C1 was capable of ethylene polymerization under 3 MPa,and produced polyethylene products with narrow polydispersity (1.16-1.73) and molecular weights in the range of 2.6-4.95 kg/mol.

  16. 7-[(3,5-Di-tert-butyl-2-hydroxybenzylideneamino]-4-methyl-2H-chromen-2-one

    Directory of Open Access Journals (Sweden)

    Orhan Büyükgüngör

    2010-10-01

    Full Text Available The title compound, C25H29NO3, is a Schiff base derivative of coumarin 120. There are two structurally similar but crystallographically independent molecules in the asymmetric unit. Both molecules exist in E configurations with respect to the C=N double bonds. The dihedral angles between the coumarin and 3,5-di-tert-butyl-2-hydroxybenzylidene ring planes are 4.62 (7 and 14.62 (7° for the two molecules. Intramolecular O—H...N hydrogen bonding involving the O—H groups and the azomethine N atoms generate S(6 rings. In the crystal structure, independent molecules are linked by C—H...π interactions, with groups of four molecules stacked along the c axis.

  17. A subchronic (180-day) oral toxicity study of ethyl tertiary-butyl ether, a bioethanol, in rats.

    Science.gov (United States)

    Miyata, Katsumi; Koga, Takayuki; Aso, Sunao; Hoshuyama, Satsuki; Ajimi, Syozo; Furukawa, Kotaro

    2014-07-01

    A subchronic (180-day) toxicity study was conducted to evaluate the effects of ethyl tertiary-butyl ether (ETBE), a biomass fuel, in male and female rats. ETBE was administered at dose levels of 0, 5, 25, 100 and 400 mg/kg/body weight (b.w.)/day by gavage. No treatment-related adverse effects were observed at 5, 25 or 100 mg/kg. Centrilobular hypertrophy of hepatocytes was observed in males and females and their relative liver weights were increased, suggesting enhanced metabolic activity. From these results, we concluded that the no observed adverse effect level of ETBE was 100 mg/kg b.w./day under the conditions tested.

  18. ETBE (ethyl tert butyl ether) and TAME (tert amyl methyl ether) affect microbial community structure and function in soils.

    Science.gov (United States)

    Bartling, Johanna; Esperschütz, Jürgen; Wilke, Berndt-Michael; Schloter, Michael

    2011-03-15

    Ethyl tert butyl ether (ETBE) and tert amyl methyl ether (TAME) are oxygenates used in gasoline in order to reduce emissions from vehicles. The present study investigated their impact on a soil microflora that never was exposed to any contamination before. Therefore, soil was artificially contaminated and incubated over 6 weeks. Substrate induced respiration (SIR) measurements and phospholipid fatty acid (PLFA) analysis indicated shifts in both, microbial function and structure during incubation. The results showed an activation of microbial respiration in the presence of ETBE and TAME, suggesting biodegradation by the microflora. Furthermore, PLFA concentrations decreased in the presence of ETBE and TAME and Gram-positive bacteria became more dominant in the microbial community.

  19. Biological Activity of Methyl tert-butyl Ether in Relation to Soil Microorganisms has a Negative Environmental Impact

    Directory of Open Access Journals (Sweden)

    Gholam H.S. Bonjar

    2005-01-01

    Full Text Available Fuel oxygenates are added to gasoline to enhance combustion efficiency of automobiles and reduce air pollution. Methyl tert-butyl ether (MTBE is the most commonly used oxygenate because of its low cost, high-octane level and ease of blending with gasoline. However, due to its water solubility, high mobility and low biodegradability it leaches in soil subsurface at the speed of groundwater. Amending gasoline with MTBE has made a widespread contamination of groundwater, surface waters in coastal environments and at low levels in well water. Although current public concern about MTBE contamination is widely discussed, but its adverse effects on soil micro flora is not yet understood. Soil Streptomycetes are beneficial to soil productivity and are of the major contributors to the biological buffering of soils having antagonistic activity against wide spectrum of pathogenic bacteria and fungi. Streptomyceticidal activity of Methyl tert-butyl ether (MTBE is being reported here. Adverse effect of MTBE against four soil-inhabitant Streptomyces spp. isolates and two plant root-pathogens was investigated. To elucidate antimicrobial activity of MTBE, it was tested against four soil isolates of Streptomyces; a plant bacterial-pathogen, Erwinia carotovora and a plant root fungal-pathogen, Fusarium solani. MTBE did not reveal any growth inhibitory-activity against E. carotovora and F. solani but showed strong inhibitory effect against Streptomyces spp. isolates. The Minimum Inhibitory Concentration (MIC was 1/800 of the original MTBE. Fuel leaks and spills can adversely suppress or eliminate the Streptomyces role in the soil causing alteration in the balance of soil micro flora. This change will lead to domination of microorganisms with adverse biological or ecological effects. Fortunately, major oil companies have decided to phase out MTBE from automobile fuels because of its adverse effect on environment and human health.

  20. Simultaneous Determination of Tert-Butyl Hydroquinone and Butylated Hydroxyanisole in Foods by High Performance Liquid Chromatography with Fluorimetric Detection%反相高效液相色谱-荧光法同时测定食品中叔丁基对苯二酚和叔丁基羟基茴香醚的含量

    Institute of Scientific and Technical Information of China (English)

    徐琴; 汤志旭; 林洪; 江志刚; 牟志春

    2008-01-01

    油溶性抗氧化剂叔丁基对苯二酚(tert-butyl hydroquinone,TBHQ)、叔丁基羟基茴香醚(butylated hydroxyanisole,BHA)和2,6-二叔丁基对甲酚(butylated hydroxytoluene,BHT)是目前最常用的化学合成抗氧化剂,能够有效阻止或延迟油脂氧化变质。然而TBHQ、BHA和BHT均具有一定的急性毒性和慢性致癌作用,过量添加会损害人体健康,

  1. Solid state {sup 1}H spin-lattice relaxation and isolated-molecule and cluster electronic structure calculations in organic molecular solids: The relationship between structure and methyl group and t-butyl group rotation

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xianlong, E-mail: WangXianlong@uestc.edu.cn, E-mail: pbeckman@brynmawr.edu [Key Laboratory for NeuroInformation of Ministry of Education, School of Life Science and Technology, University of Electronic Science and Technology of China, 4 North Jianshe Rd., 2nd Section, Chengdu 610054 (China); Mallory, Frank B. [Department of Chemistry, Bryn Mawr College, 101 North Merion Ave., Bryn Mawr, Pennsylvania 19010-2899 (United States); Mallory, Clelia W. [Department of Chemistry, Bryn Mawr College, 101 North Merion Ave., Bryn Mawr, Pennsylvania 19010-2899 (United States); Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323 (United States); Odhner, Hosanna R.; Beckmann, Peter A., E-mail: WangXianlong@uestc.edu.cn, E-mail: pbeckman@brynmawr.edu [Department of Physics, Bryn Mawr College, 101 North Merion Ave., Bryn Mawr, Pennsylvania 19010-2899 (United States)

    2014-05-21

    We report ab initio density functional theory electronic structure calculations of rotational barriers for t-butyl groups and their constituent methyl groups both in the isolated molecules and in central molecules in clusters built from the X-ray structure in four t-butyl aromatic compounds. The X-ray structures have been reported previously. We also report and interpret the temperature dependence of the solid state {sup 1}H nuclear magnetic resonance spin-lattice relaxation rate at 8.50, 22.5, and 53.0 MHz in one of the four compounds. Such experiments for the other three have been reported previously. We compare the computed barriers for methyl group and t-butyl group rotation in a central target molecule in the cluster with the activation energies determined from fitting the {sup 1}H NMR spin-lattice relaxation data. We formulate a dynamical model for the superposition of t-butyl group rotation and the rotation of the t-butyl group's constituent methyl groups. The four compounds are 2,7-di-t-butylpyrene, 1,4-di-t-butylbenzene, 2,6-di-t-butylnaphthalene, and 3-t-butylchrysene. We comment on the unusual ground state orientation of the t-butyl groups in the crystal of the pyrene and we comment on the unusually high rotational barrier of these t-butyl groups.

  2. Photosynthetic characteristics of cassava cultivars treated with fluazifop-p-butyl and fomesafen = Características fotossintéticas de cultivares de mandioca tratadas com fluazifop-p-butyl e fomesafen

    Directory of Open Access Journals (Sweden)

    Hellen Martins da Silveira

    2012-12-01

    Full Text Available The spending on weed control is an important component of production cost of cassava. It may be due to a limited availability of registered herbicides for use on this culture. To select new selective herbicides for cultures, it may be used the evaluation of plant photosynthetic characteristics after application. Thus, with this work, it was aimed to evaluate the effects of fluazifop-p-butyl and fomesafen herbicides, applied separately and in mixture, on the photosynthetic variables of five cassava cultivars (Cacau-UFV, Platina, Coqueiro, Coimbra and IAC-12. The treatments were applied 30 days after planting, when the cassava plants had approximately 30 centimeters of height. 30 days after application of treatments, it was evaluated substomatic CO2 concentration, photosynthetic rate and CO2 consumption by culture. The mixture of the herbicides fluazifopp - butyl + fomesafen caused increases in the quantity of CO2 consumed, CO2 concentration in the substomatal chambers and photosynthetic rate of the cultivars evaluated. However, the application of herbicides separately did not alter the characteristics evaluated with potential for use in post-emergence of cassava.= Um dos mais importantes componentes do custo de produção da mandioca refere-se aos gastos com o controle de plantas daninhas. Isto pode ser atribuído a pouca disponibilidade de herbicidas registrados para uso nessa cultura. Uma das maneiras para selecionar novos agrotóxicos seletivos para culturas pode ser através da avaliação de características fotossintéticas de plantas após aplicação de herbicidas. Objetivou-se com este trabalho avaliar os efeitos dos herbicidas fluazifop-p-butyl e fomesafen, aplicados isoladamente e em mistura, sobre as variáveis fotossintéticas de cinco cultivares de mandioca (Cacau- UFV, Platina, Coqueiro, Coimbra e IAC-12. Os tratamentos foram aplicados aos 30 dias após o plantio, quando as plantas de mandioca apresentavam aproximadamente 30 cm de

  3. Nodulação e crescimento de variedades de soja RR sob aplicação de glyphosate, fluazifop-p-butyl e fomesafen GR glycine max nodulation and growth under glyphosate, fluazifop-p-butyl and fomesafen aplication

    Directory of Open Access Journals (Sweden)

    E.C. Dvoranen

    2008-01-01

    Full Text Available O objetivo deste trabalho foi avaliar os efeitos causados por aplicações dos herbicidas glyphosate, fluazifop-p-butyl e fomesafen, em diferentes formas de aplicação, sobre a nodulação e o crescimento inicial de duas variedades de soja RR. Os tratamentos foram organizados em arranjo fatorial 6 x 2, no qual foram avaliadas seis formas de aplicação de herbicida (testemunha sem herbicida, aplicação seqüencial de fomesafen/fomesafen, aplicação seqüencial de fomesafen/[fomesafen+fluazifop-p-butyl], fluazifop-p-butyl em aplicação única, aplicação seqüencial de glyphosate/glyphosate e glyphosate em aplicação única e duas variedades de soja (BRS 245 RR e BRS 247 RR. Com relação à nodulação, a aplicação seqüencial de fomesafen/fomesafen foi a forma mais seletiva. A variedade BRS 245 RR mostrou-se mais tolerante do que a variedade BRS 247 RR às aplicações dos herbicidas. Número e matéria seca de nódulos da variedade BRS 247 RR são reduzidos por aplicações em dose única de fluazifop-p-butyl e glyphosate.The objective of this work was to evaluate the effects of the herbicides glyphosate, fluazifop-p-butyl and fomesafen, applied by different methods, on nodulation and initial growth of two glyphosate-resistant (GR soybean varieties. Treatments were arranged in a 6 x 2 factorial, with six herbicide application methods (no-herbicide check, fomesafen/fomesafen sequential application, fomesafen/[fomesafen+fluazifop-p-butyl sequential application], fluazifop-p-butyl single application, glyphosate/glyphosate sequential application and glyphosate single application and two soybean varieties (BRS 245 RR and BRS 247 RR. Regarding soybean nodulation, fomesafen/fomesafen sequential application was the most selective herbicide application method. Variety BRS 245 RR was more tolerant than BRS 247 RR to the herbicides evaluated. Number and dry weight of nodules decreased after single applications of fluazifop-p-butyl and glyphosate.

  4. Distribution of methyl tert-butyl ether (MTBE) and selected water-quality constituents in the surficial aquifer at the Dover National Test Site, Dover Air Force Base, Delaware, 2001

    Science.gov (United States)

    Stewart, Marie; Guertal, William R.; Barbaro, Jeffrey R.; McHale, Timothy J.

    2004-01-01

    A joint study by the Dover National Test Site, Dover Air Force Base, Delaware, and the U.S. Geological Survey was conducted from June 27 through July 18, 2001, to determine the spatial distribution of the gasoline oxygenate additive methyl tert-butyl ether and selected water-quality constituents in the surficial aquifer underlying the Dover National Test Site. This report provides a summary assessment of the distribution of methyl tert-butyl ether and a preliminary screening of selected constituents that may affect natural attenuation and remediation demonstrations at the Dover National Test Site. The information gathered during this study is designed to assist potential remedial investigators who are considering conducting a methyl tert-butyl ether remedial demonstration at the test site. In addition, the study supported a planned enhanced bioremediation demonstration and assisted the Dover National Test Site in identifying possible locations for future methyl tert-butyl ether remediation demonstrations. A direct-push drill rig was used to collect a total of 147 ground-water samples (115 VOC samples and 32 quality-assurance samples) at varying depths. Volatile organic compounds were above the method reporting limits in 59 of the 115 ground-water samples. The concentrations ranged from below detection limits to maximum values of 12.4 micrograms per liter of cis-1,2-dichloro-ethene, 1.14 micrograms per liter of trichloro-ethene, 2.65 micrograms per liter of tetrachloro-ethene, 1,070 micrograms per liter of methyl tert-butyl ether, 4.36 micrograms per liter of benzene, and 1.8 micrograms per liter of toluene. Vinyl chloride, ethylbenzene, p,m-xylene, and o-xylene were not detected in any of the samples collected during this investigation. Methyl tert-butyl ether was detected in 47 of the 115 ground-water samples. The highest concentrations of methyl tert-butyl ether were detected in the surficial aquifer from ?4.6 to 6.4 feet mean sea level; however, methyl tert-butyl

  5. Study of an aquifer contaminated by ethyl tert-butyl ether (ETBE): Site characterization and on-site bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Fayolle-Guichard, Francoise, E-mail: francoise.fayolle@ifpen.fr [IFP Energies nouvelles, 1 et 4 avenue de Bois-Preau, 92852 Rueil-Malmaison (France); Durand, Jonathan [Institut EGID Bordeaux 3, 1 Allee Daguin 33607 Pessac Cedex (France); SERPOL, 2 chemin du Genie, BP 80, 69633 Venissieux Cedex (France); Cheucle, Mathilde [SERPOL, 2 chemin du Genie, BP 80, 69633 Venissieux Cedex (France); Rosell, Monica [Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research - UFZ, Permoserstrasse 15, 04318 Leipzig (Germany); Michelland, Rory Julien [Universite de Lyon, F-69622 Lyon (France); Universite Lyon 1, Villeurbanne (France); CNRS, UMR5557, Ecologie Microbienne (France); Tracol, Jean-Philippe [SERPOL, 2 chemin du Genie, BP 80, 69633 Venissieux Cedex (France); Le Roux, Francoise [IFP Energies nouvelles, 1 et 4 avenue de Bois-Preau, 92852 Rueil-Malmaison (France); Grundman, Genevieve [Universite de Lyon, F-69622 Lyon (France); Universite Lyon 1, Villeurbanne (France); CNRS, UMR5557, Ecologie Microbienne (France); Atteia, Olivier [Institut EGID Bordeaux 3, 1 Allee Daguin 33607 Pessac Cedex (France); Richnow, Hans H. [Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research - UFZ, Permoserstrasse 15, 04318 Leipzig (Germany); Dumestre, Alain [SERPOL, 2 chemin du Genie, BP 80, 69633 Venissieux Cedex (France); and others

    2012-01-30

    Highlights: Black-Right-Pointing-Pointer Ethyl tert-butyl ether (ETBE) (>300 mg L{sup -1}) found in a groundwater (gas-station). Black-Right-Pointing-Pointer No significant carbon or hydrogen isotopic fractionation of ETBE along the plume. Black-Right-Pointing-Pointer MC-IFP culture degraded ETBE (0.91 mg L{sup -1} h{sup -1}) and BTEX (0.64 mg L{sup -1} h{sup -1}). Black-Right-Pointing-Pointer A pilot plant (2 m{sup 3}) inoculated with MC-IFP degraded ETBE in groundwater (15 Degree-Sign C). Black-Right-Pointing-Pointer ethB gene (ETBE biodegradation) amplified during bioaugmentation (5 Multiplication-Sign 10{sup 6}ethB gene copies L{sup -1}). - Abstract: Ethyl tert-butyl ether (ETBE) was detected at high concentration (300 mg L{sup -1}) in the groundwater below a gas-station. No significant carbon neither hydrogen isotopic fractionation of ETBE was detected along the plume. ETBE and BTEX biodegradation capacities of the indigenous microflora Pz1-ETBE and of a culture (MC-IFP) composed of Rhodococcus wratislaviensis IFP 2016, Rhodococcus aetherivorans IFP 2017 and Aquincola tertiaricarbonis IFP 2003 showed that ETBE and BTEX degradation rates were in the same range (ETBE: 0.91 and 0.83 mg L{sup -1} h{sup -1} and BTEX: 0.64 and 0.82 mg L{sup -1} h{sup -1}, respectively) but tert-butanol (TBA) accumulated transiently at a high level using Pz1-ETBE (74 mg L{sup -1}). An on-site pilot plant (2 m{sup 3}) filled with polluted groundwater and inoculated by MC-IFP, successfully degraded four successive additions of ETBE and gasoline. However, an insignificant ETBE isotopic fractionation was also accompanying this decrease which suggested the involvement of low fractionating-strains using EthB enzymes, but required of additional proofs. The ethB gene encoding a cytochrome P450 involved in ETBE biodegradation (present in R. aetherivorans IFP 2017) was monitored by quantitative real-time polymerase chain reaction (q-PCR) on DNA extracted from water sampled in the pilot plant

  6. Phase equilibria study of the binary systems (1-butyl-3-methylimidazolium thiocyanate ionic liquid + organic solvent or water).

    Science.gov (United States)

    Domańska, Urszula; Laskowska, M; Pobudkowska, Aneta

    2009-05-07

    (Solid + liquid) phase equilibria (SLE) for the binary systems, ionic liquid (IL) 1-butyl-3-methylimidazolium thiocyanate [BMIM][SCN] with an alcohol (1-octanol, 1-nonanol, 1-decanol, 1-undecanol, or 1-dodecanol) or water, and (liquid + liquid) phase equilibria (LLE) for the binary systems of [BMIM][SCN] with an alkane (n-hexane, n-heptane, n-octane, n-nonane, or n-decane), benzene, an alkylbenzenes (toluene or ethylbenzene), tetrahydrofuran (THF), cycloalkanes (cyclohexane or cycloheptane), or ethers (di-n-propyl ether, di-n-butyl ether, di-n-pentyl ether, n-butylmethyl ether, tert-butylmethyl ether (MTBE), or tert-butylethyl ether (ETBE)) have been determined at ambient pressure. A dynamic method was used over a broad range of mole fractions and temperatures from 250 to 430 K. In the case of systems IL + alkane, cycloalkane, or ether, the mutual immiscibility with an upper critical solution temperature (UCST) was detected, and in the systems of IL + benzene, alkylbenzene, or THF, the mutual immiscibility with a lower critical solution temperature (LCST) was observed. UV-vis spectroscopy was used to determine the very small compositions of the IL in the n-hexane (about 2 x 10(-5) IL mole fraction), benzene (about 2 x 10(-3) IL mole fraction), cyclohexane (about 2 x 10(-5) IL mole fraction), and THF (about 1.2 x 10(-2) IL mole fraction). For the binary systems containing alcohol, it was noticed that with increasing chain length of an alcohol, the solubility decreases. The basic thermal properties of the pure IL, that is, the glass-transition temperature as well as the heat capacity at the glass-transition temperature, have been measured using a differential scanning microcalorimetry technique (DSC). Decomposition of the IL was detected by the simultaneous TG/DTA experiments. Well-known UNIQUAC, Wilson, and NRTL equations have been used to correlate the experimental SLE data sets for alcohols and water. For the systems containing immiscibility gaps {IL + alkane

  7. Comparison of scaffold-enhanced albumin and n-butyl-cyanoacrylate adhesives for joining of tissue in a porcine model

    Science.gov (United States)

    McNally-Heintzelman, Karen M.; Riley, Jill N.; Heintzelman, Douglas L.

    2003-06-01

    An ex vivo study was conducted to compare the tensile strength of tissue samples repaired using three different techniques: (i) application of a scaffold-enhanced light-activated albumin protein solder, (ii) application of a scaffold-enhanced n-butyl-cyanoacrylate adhesive, and (iii) repair via conventional suture technique. Biodegradable polymer scaffolds of controlled porosity were fabricated with poly(L-lactic-co-glycolic acid) and salt particles using a solvent-casting and particulate-leaching technique. Group I porous scaffolds were doped with protein solder composed of 50%(w/v) bovine serum albumin solder and 0.5mg/ml indocyanine green dye mixed in deionized water, and activated with an 808-nm diode laser. Group II scaffolds were doped with n-butyl-cyanoacrylate, and required no light-activation. No stay sutures were required for Group I or II experiments. Group III repairs were performed using a single 4-0 suture. Thirteen organs were tested ranging from skin to liver to the small intestine, as well as the coronary, pulmonary, carotid, femoral and splenic arteries. Acute breaking strengths were measured and the data were analyzed by Student"s T-test. Using the protein solder of Group I, repairs formed on the ureter were most successful followed by small intestine, sciatic nerve, spleen, atrium, kidney, muscle, skin and ventricle. The strongest vascular repairs were achieved in the carotid artery and femoral artery. Overall, the tensile strength of Group III repairs performed via suture techniques were equivalent in magnitude to that of Group I repairs, however, a larger variance was observed in the suture repair group. Group II repairs utilizing the cyanoacrylate-doped scaffold all performed extremely well. Bonds formed using the Group II adhesive were approximately 30% stronger than Group I and III organ repairs and approximately 20% stronger than Group I and III vascular repairs. Application of the polymer scaffold assists in tissue alignment and reduces

  8. Solid-Liquid Equilibria of Musk Ketone, Musk Xylene and 1,3-Dimethyl-2,4-Dinitro-5-Tert-Butyl Benzene

    Institute of Scientific and Technical Information of China (English)

    曲红梅; 白鹏; 杨志才; 余国琮

    2004-01-01

    The solid-liquid equilibria of musk ketone + musk xylene, musk xylene+1,3-dimethyl-2,4-dinitro-5-tert-butyl benzene are measured by differential scanning calorimeter (DSC), these systems are proved to be simple eutectics. Moreover the melting points and the fusion enthalpies of musk ketone, musk xylene and 1,3-dimethyl-2,4-dinitro-5-tert-butyl benzene are also measured by the DSC. These solid-liquid equilibrium data and the heats of fusion are reported for the first time. Then UNIFAC model is used to correlate the solid-liquid equilibrium data.It is shown that the solid-liquid equilibria of musk systems can be predicted bv the UNIFAC model.

  9. SYNTHESIS AND CHARACTERISTICS OF GRAFT COPOLYMERS OF POLY (BUTYL ACRYLATE AND CELLULOSE WITH ULTRASONIC PROCESSING AS A MATERIAL FOR OIL ABSORPTION

    Directory of Open Access Journals (Sweden)

    Ping Qu

    2011-11-01

    Full Text Available A series of materials used for oil absorption based on cellulose fiber grafted with butyl acrylate (BuAc have been prepared by radical polymerization under ultrasonic waves processing. Effects of ultrasonic dose for the maximum graft yield were considered. The dependency of optimum conditions for oil absorption rate on parameters such as ultrasonic processing time and ultrasonic power were also determined. Fourier infrared (FT-IR analysis was used to confirm the chemical reaction taking place between cellulose and butyl acrylate. The thermogravimetric behavior of the graft copolymer was characterized by thermogravimetric analysis (TGA. Scanning electron microscope (SEM analysis was used to determine the surface structure of the grafted material. With the increase of the ultrasonic treatment dose, the surface of the ultrasonic processed material became more regular, and the material was transformed into a homogeneous network polymer having a good structure and good adsorbing ability.

  10. N-Substituted-2-butyl-5-chloro-3H-imidazole-4-carbaldehyde derivatives as anti-tumor agents against Ehrlich ascites tumor cells in vivo.

    Science.gov (United States)

    Kumar, C Anil; Swamy, S Nanjunda; Gaonkar, S L; Basappa; Salimath, Bharathi P; Rangappa, Kanchugarakoppal S

    2007-05-01

    A new series of N-substituted 2-butyl-5-chloro-3H-imidazole-4-carbaldehyde derivatives were synthesized by using the different bioactive heteroaralkyl halides with 2-butyl-4-chloro-1H-imidazole-5-carbaldehyde in presence of powdered potassium carbonate in DMF medium. These compounds were screened for their antitumor activity. Our results show that treatment of imidazole derivatives inhibit proliferation EAT cells, decreases the ascites volume and increases the survivability of the animals in vivo. These compounds also inhibited the cellular proliferation of HUVEC cells in vitro by MTT assay. Further, these compounds could induce apoptosis, which is evident by the nuclear condensation of imidazole derivatives treated EAT cells in vivo by the cytological analysis. We have identified that pyrrolidine substituted imidazole derivative as potent anti-tumor compound. These inhibitors could represent as promising candidates for anticancer therapies, where the formation of peritoneal malignant ascites is a major cause of morbidity and mortality.

  11. The study on grafting comonomer of n-butyl acrylate and styrene onto poly(ethylene terephthalate) film by gamma-ray induced graft copolymerization

    Energy Technology Data Exchange (ETDEWEB)

    Ping Xiang; Wang Mozhen [CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026 (China); Ge Xuewu, E-mail: xwge@ustc.edu.c [CAS Key Laboratory of Soft Matter Chemistry, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026 (China)

    2010-09-15

    Poly(ethylene terephthalate) (PET) film was successfully grafted with n-butyl acrylate and styrene comonomer through gamma-ray induced graft copolymerization. The degree of grafting (DG) and the composition of grafted side chain were characterized by {sup 1}H NMR. It was found that St can inhibit the homopolymerization of BA effectively and increase the DG when the concentration of comonomer mixture is kept constant. The proportion of St to BA in grafted side chain has a positive dependence on the feed ratio of St, which ultimately approaches the feed ratio. The thermal properties of poly(ethylene terephthalate)-graft-poly(n-butyl acrylate-co-styrene) (PET-g-P(BA-co-St)) films were investigated by differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA). The T{sub g} of PET decreases with the DG, indicating that the grafted P(BA-co-St) copolymer has good compatibility with PET backbone.

  12. SYNTHESIS AND FREE RADICAL RING-OPENING POLYMERIZATION OF 2 - METHYL-AND 2- METHYL- 9- n- BUTYL- (- 7- METHYLENE- 1,4,6 - TRIOXASPIRO (4, 4 )NONANE )

    Institute of Scientific and Technical Information of China (English)

    PAN Caiyuan; WANG Yin

    1989-01-01

    This paper describes the synthesis and free radical ring- opening polymerization of 2 - methyl-and2 - methyl - 9 - n - butyl ( - 7 - methylene - 1,4, 6 - trioxaspiro (4, 4 ) nonane ). The structures of the two polymers were verified by IR, 1H and 13C NMR spectra. The substituent on 9-position of 7-methylene- trioxaspiro (4, 4 ) nona ne affects the structure of polymer and polymerization activity. The polymerization mechanism is discussed .

  13. Effects of the Ionic Liquid 1-Butyl-3-methylimidazolium Chloride on the Growth and Ethanol Fermentation of Saccharomyces cerevisiae AY92022

    OpenAIRE

    Zhu, S.; Yu, P.; Tong, Y; Chen, R.; Lv, Y.; Zhang, R.; Lei,M.; Ji, J; Chen, Q; Y Wu

    2012-01-01

    Use of ionic liquids has provided a potential effective alternative in the conversion of carbohydrates in lignocellulosic materials into fermentable sugars for ethanol production. To evaluate how the remained ionic liquids in the fermentable sugars affect the subsequent ethanol fermentation process, the effects of ionic liquid 1- butyl-3-methylimidazolium chloride ([Bmim]Cl) in the medium at different concentrations from 10–3 to 1 g L–1 on the morphological structure, growth and ethanol ferme...

  14. 2-(4-Bromobenzyl-5,11,17,23-tetra-tert-butyl-25,26,27,28-tetramethoxycalix[4]arene

    Directory of Open Access Journals (Sweden)

    Conrad Fischer

    2009-07-01

    Full Text Available In the title compound, C55H69BrO4, the calixarene molecule displays a `partial cone' conformation bearing the lateral substituent in a sterically favorable equatorial arrangement between two syn-orientated arene units. The crystal packing is stabilized by weak C—H...π contacts, involving one tert-butyl group, and π–stacking interactions of the lateral bromobenzene units [centroid–centroid distance = 3.706 (1 Å].

  15. Optical and charge transport properties of N-butyl-1,8-naphthalimide derivatives as organic light-emitting materials: A theoretical study

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Fuyu [College of Physical and Electronic and Information Engineering, Chifeng University, Chifeng 024000 (China); Jin, Ruifa, E-mail: Ruifajin@163.com [College of Chemistry and Chemical Engineering, Chifeng University, Chifeng 024000 (China)

    2014-05-01

    A series of N-butyl-1,8-naphthalimide derivatives have been designed to explore their optical, electronic, and charge transport properties as charge transport and/or luminescent materials for organic light-emitting diodes (OLEDs). The frontier molecular orbitals (FMOs) analysis has turned out that the vertical electronic transitions of absorption and emission are characterized as intramolecular charge transfer (ICT). The calculated results show that the optical and electronic properties of N-butyl-1,8-naphthalimide derivatives are affected by the substituent groups in 4-position of 1,8-naphthalimide ring. Our results suggest that N-butyl-1,8-naphthalimide derivatives with biphenyl (1), 2-phenylthiophene (2), 2-(thiophen-2-yl)thiophene (3), 2,3-dihydrothieno[3,4-b][1,4]dioxine (4), 2-phenyl-1,3,4-oxadiazole (5), benzo[c][1,2,5]thiadiazole (6), benzo[c]thiophene (7), and benzo[d]thieno[3,2-b]thiophene (8) fragments are expected to be promising candidates for luminescent materials for OLEDs, particularly for 1–3 and 5. In addition, 7 and 8 can be used as promising hole transport materials for OLEDs. - Highlights: • A series of N-butyl-1,8-naphthalimide derivatives is investigated. • Optical and electronic properties are affected by their substituent groups. • The vertical electronic transitions are characterized as intramolecular charge transfer. • All derivatives are promising luminescent materials for OLEDs. • Some derivatives can be used as promising hole transport materials for OLEDs.

  16. R-(+)-ABP a novel derivative of 3-n-butyl-phthalide possesses anti-convulsant and neuroprotective properties in rodents

    Institute of Scientific and Technical Information of China (English)

    ELESTAGE; A.ROGER; L.DANOBER; ERENARD; X-Q.PENG; Z.GUO; J.T.ZHANG

    2004-01-01

    ABP is a novel phthalide derivative of 3-n-butyl-phthalide (NBP) synthesized at the Beijing Institute of Materia Medica.NBP was isolated from several plants including Apium graveolens Linn. The juice squeezed from fresh celery leaves has long been used in Southeastern China for the treatment of epilepsy, and NBP has been reported to possess anti-convulsant properties (Drugs Future 2000; 25: 16-23). The present study

  17. Folate-decorated chitosan/doxorubicin poly(butyl)cyanoacrylate nanoparticles for tumor-targeted drug delivery

    Energy Technology Data Exchange (ETDEWEB)

    Duan Jinghua [Xiangya Hospital, Central South University, Hepatobiliary and Enteric Surgery Research Center (China); Liu Mujun [Central South University, School of Biological Science and Technology (China); Zhang Yangde; Zhao Jinfeng; Pan Yifeng [Xiangya Hospital, Central South University, Hepatobiliary and Enteric Surgery Research Center (China); Yang Xiyun, E-mail: bax_2007@126.com [Central South University, School of Metallurgical Science and Engineering (China)

    2012-03-15

    A novel chitosan coated poly(butyl cyanoacrylate) (PBCA) nanoparticles loaded doxorubicin (DOX) were synthesized and then conjugated with folic acid to produce a folate-targeted drug carrier for tumor-specific drug delivery. Prepared nanoparticles were surface modified by folate for targeting cancer cells, which is confirmed by FTIR spectroscopy and characterized for shape, size, and zeta potential measurements. The size and zeta potential of prepared DOX-PBCA nanoparticles (DOX-PBCA NPs) were almost 174 {+-} 8.23 nm and +23.14 {+-} 4.25 mV, respectively with 46.8 {+-} 3.32% encapsulation capacity. The transmission electron microscopy study revealed that preparation allowed the formation of spherical nanometric and homogeneous. Fluorescent microscopy imaging and flow cytometry analysis revealed that DOX-PBCA NPs were endocytosed into MCF-7 cells through the interaction with overexpressed folate receptors on the surface of the cancer cells. The results demonstrate that folate-conjugated DOX-PBCA NPs drug delivery system could provide increased therapeutic benefit by delivering the encapsulated drug to the folate receptor positive cancer cells.

  18. A Study of the Catalysts for the Complete Oxidation of Low Concentration Ethyl Acetate and n-Butyl Acetate

    Institute of Scientific and Technical Information of China (English)

    DUAN; ZhiYing

    2001-01-01

    In this work, we have synthesized mixed oxides catalysts supported on γ-Al2O3,using some base metals such as La、 Sr、 Ce、 Ni、 Cu. At the space velocity of 56,000h-1 and at some range of concentration, the complete conversion temperatures( ≥ 98% )of Ethyl acetate and n-butyl acetate are 260℃ and 250℃ respectively. The work has an excellent prospect of industrial application.  I will introduce the experiment and results from the following tluee aspects. According to Figure 1, X-ray diffraction pattern of the catalyst have shown not only perovskite structure but also much independent CeO2 phase. During the preparation, the CeO2 was coated over support γ-A12O3 for the better Oxygen storage capacity .By co1mparison, we found that the activity of the catalyst with CeO2 was higher than the activity of the catalyst without CeO2.……

  19. Solvent Extraction of Tellurium from Chloride Solutions Using Tri-n-butyl Phosphate: Conditions and Thermodynamic Data

    Directory of Open Access Journals (Sweden)

    Dongchan Li

    2014-01-01

    Full Text Available The extractive separation of tellurium (IV from hydrochloric acid media with tri-n-butyl phosphate (TBP in kerosene was investigated. The dependence on the extraction of tellurium species, concentrations of tellurium and TBP, extraction time and stage, organic/aqueous ratio, and interferences from coexist metallic ions were examined and are discussed. Besides, the stripping agent and stripping time were also studied. It was found that the extraction reaction corresponds to the neutral complex formation mechanism and the extracted species is TeCl4·3TBP and that the extraction process is exothermic. The thermodynamic parameters of enthalpy ΔH, entropy ΔS, and free energy ΔG of the extraction process were evaluated at −26.2 kJ·mol−1, −65.6 J·mol−1·K−1, and −7.0 kJ·mol−1, respectively at 293 K.

  20. Calorimetric determination of the enthalpy of 1-butyl-3-methylimidazolium bromide synthesis: a key quantity in thermodynamics of ionic liquids.

    Science.gov (United States)

    Paulechka, Yauheni U; Kabo, Andrey G; Blokhin, Andrey V

    2009-11-05

    The enthalpy of the 1-butyl-3-methylimidazolium bromide [C(4)mim]Br ionic liquid synthesis reaction 1-methylimidazole (liq) + 1-bromobutane (liq) --> [C(4)mim]Br (liq) was determined in a homemade small-volume isoperibol calorimeter to be Delta(r)H degrees (298) = -87.7 +/- 1.6 kJ x mol(-1). The activation energy for this reaction in a homogeneous system E(A) = 73 +/- 4 kJ x mol(-1) was found from the results of calorimetric measurements. The formation enthalpies for the crystalline and liquid [C(4)mim]Br were determined from the calorimetric data: Delta(f)H degrees (298)(cr) = -178 +/- 5 kJ x mol(-1) and Delta(f)H degrees (298)(liq) = -158 +/- 5 kJ x mol(-1). The ideal-gas formation enthalpy of this compound Delta(f)H degrees (298)(g) = 16 +/- 7 kJ x mol(-1) was calculated using the methods of quantum chemistry and statistical thermodynamics. The vaporization enthalpy of [C(4)mim]Br, Delta(vap)H degrees (298) = 174 +/- 9 kJ x mol(-1), was estimated from the experimental and calculated formation enthalpies. It was demonstrated that vapor pressure of this ionic liquid cannot be experimentally determined.

  1. Health Risk Assessment for Inhalation Exposure to Methyl Tertiary Butyl Ether at Petrol Stations in Southern China.

    Science.gov (United States)

    Hu, Dalin; Yang, Jianping; Liu, Yungang; Zhang, Wenjuan; Peng, Xiaowu; Wei, Qinzhi; Yuan, Jianhui; Zhu, Zhiliang

    2016-02-06

    Methyl tertiary butyl ether (MTBE), a well known gasoline additive, is used in China nationwide to enhance the octane number of gasoline and reduce harmful exhaust emissions, yet little is known regarding the potential health risk associated with occupational exposure to MTBE in petrol stations. In this study, 97 petrol station attendants (PSAs) in southern China were recruited for an assessment of the health risk associated with inhalation exposure to MTBE. The personal exposure levels of MTBE were analyzed by Head Space Solid Phase Microextraction GC/MS, and the demographic characteristics of the PSAs were investigated. Cancer and non-cancer risks were calculated with the methods recommended by the United States Environmental Protection Agency. The results showed that the exposure levels of MTBE in operating workers were much higher than among support staff (p operating workers, and 0.026 to 0.049 per 10⁶ for support staff, which are below the typical target range for risk management of 1 × 10(-6) to 1 × 10(-4); The hazard quotients (HQs) for all subjects were exposure of PSAs in southern China is in a low range which does not seem to be a significant health risk.

  2. Determination of the solubility parameter of ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate by inverse gas chromatography.

    Science.gov (United States)

    Ma, Xiaohong; Wang, Qiang; Li, Xiaoping; Tang, Jun; Zhang, Zhengfang

    2015-11-01

    Thermodynamic properties of ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM] BF4) were determined via inverse gas chromatography (IGC). Two groups of solvents with different chemical natures and polarities were used to obtain information about [BMIM] BF4-solvent interactions. The specific retention volume, molar heat of sorption, weight fraction activity coefficient, Flory-Huggins interaction parameter as well as solubility parameter were also determined in a temperature range of 333 - 373 K. The results showed that the selected solvents n-C10 to n-C12, carbon tetrachloride, cyclohexane and toluene were poor solvents for [BMIM] BF4, while dichloromethane, acetone, chloroform, methyl acetate, ethanol and methanol were favorite solvents for [BMIM] BF4. In addition, the solubility parameter of [ BMIM] BF4 was determined as 23.39 (J/cm3)0.5 by the extrapolation at 298 K. The experiment proved that IGC was a simple and accurate method to obtain the thermodynamic properties of ionic liquids. This study could be used as a reference to the application and research of the ionic liquids.

  3. A Study of the Catalysts for the Complete Oxidation of Low Concentration Ethyl Acetate and n-Butyl Acetate

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ In this work, we have synthesized mixed oxides catalysts supported on γ-Al2O3,using some base metals such as La、 Sr、 Ce、 Ni、 Cu. At the space velocity of 56,000h-1 and at some range of concentration, the complete conversion temperatures( ≥ 98% )of Ethyl acetate and n-butyl acetate are 260℃ and 250℃ respectively. The work has an excellent prospect of industrial application. I will introduce the experiment and results from the following tluee aspects. According to Figure 1, X-ray diffraction pattern of the catalyst have shown not only perovskite structure but also much independent CeO2 phase. During the preparation, the CeO2 was coated over support γ-A12O3 for the better Oxygen storage capacity .By co1mparison, we found that the activity of the catalyst with CeO2 was higher than the activity of the catalyst without CeO2.

  4. Measurement and Modeling of Vapor-Liquid Equilibrium for Ternary System Water+2-Propanol+1-Butyl-3-methylimidazolium Chloride

    Institute of Scientific and Technical Information of China (English)

    邓东顺; 乔玉珍; 姬登祥; 葛筠; 章连众

    2014-01-01

    Vapor-liquid equilibrium (VLE) data for water+2-propanol+1-butyl-3-methylimidazolium chloride ([bmim]Cl) were measured. Six sets of complete T, x, y data are reported, in which the 2-propanol mole fraction on IL-free basis is fixed separately at 0.1, 0.2, 0.4, 0.6, 0.8, and approximate 0.98, while the IL mass fraction is varied from 0.1 to 0.8, in an interval of 0.1. The non-random-two-liquid (NRTL) and electrolyte non-random-two-liquid (eNRTL) equations are used to correlate the experimental data with satisfactory results. The ternary VLE behavior is also modeled with the parameters obtained by correlating two data sets, in which the mole fraction of 2-propanol on IL-free basis is approximately 0.1 and 0.98. In this way, the six sets of data are reproduced satisfactorily. With the eNRTL model, the root-mean-square deviation for temperature is 0.82 K and that for vapor-phase mole fraction is 0.0078. The influences of IL on activity coefficients and relative volatility of the volatile components are also graphically illustrated.

  5. Selenium methylselenocysteine protects human hepatoma HepG2 cells against oxidative stress induced by tert-butyl hydroperoxide.

    Science.gov (United States)

    Cuello, Susana; Ramos, Sonia; Mateos, Raquel; Martín, M Angeles; Madrid, Yolanda; Cámara, Carmen; Bravo, Laura; Goya, Luis

    2007-12-01

    Selenium methylselenocysteine (Se-MeSeCys) is a common selenocompound in the diet with a tested chemopreventive effect. This study investigated the potential protective effect of Se-MeSeCys against a chemical oxidative stress induced by tert-butyl hydroperoxide (t-BOOH) on human hepatoma HepG2 cells. Speciation of selenium derivatives by liquid chromatography-inductively coupled plasma mass spectrometry depicts Se-MeSeCys as the only selenocompound in the cell culture. Cell viability (lactate dehydrogenase) and markers of oxidative status--concentration of reduced glutathione (GSH) and malondialdehyde (MDA), generation of reactive oxygen species (ROS) and activity of the antioxidant enzymes glutathione peroxidase (GPx) and glutathione reductase (GR)--were evaluated. Pretreatment of cells with Se-MeSeCys for 20 h completely prevented the enhanced cell damage, MDA concentration and GR and GPx activity and the decreased GSH induced by t-BOOH but did not prevent increased ROS generation. The results show that treatment of HepG2 cells with concentrations of Se-MeSeCys in the nanomolar to micromolar range confers a significant protection against an oxidative insult.

  6. Efficient hydrolysis of cellulose over a magnetic lignin-derived solid acid catalyst in 1-butyl-3-methylimidazolium chloride

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Lei; Wu, Zhen; Xu, Jiaxing; Zhou, Shouyong; Tang, Guodong [Huaiyin Normal University, Huaian (China)

    2016-04-15

    A green and efficient strategy for the hydrolysis of cellulose was developed by using a magnetic lignin-derived solid acid catalyst (MLC-SO{sub 3}H) in the presence of ionic liquid 1-butyl-3-methylimidazolium chloride ([BMIM]Cl). The results indicated that reaction temperature, reaction time, catalyst loading and water content have a big influence on the yield of total reducing sugars (TRS). By optimizing these reaction parameters, 69.3% TRS yield was observed at 140 .deg. C for 150 min with the addition of 40 wt% MLC-SO{sub 3}H and 1 wt% water. More importantly, MLC-SO{sub 3}H could be easily separated from the reaction mixture with an external magnet and could be repeatedly used five times without an obvious loss of catalytic activity, demonstrating that it possessed excellent recyclability. Furthermore, a plausible mechanism involving three consecutive processes of dissolution, adsorption and catalysis for the hydrolysis of cellulose in [BMIM]Cl over a catalyst of MLC-SO{sub 3}H was also proposed.

  7. Molecular dynamics simulations of n-hexane at 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide interface

    Science.gov (United States)

    Lísal, Martin; Izák, Pavel

    2013-07-01

    Molecular dynamics simulations of n-hexane adsorbed onto the interface of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide ([bmim][Tf2N]) are performed at three n-hexane surface densities, ranged from 0.7 to 2.3 μmol/m2 at 300 K. For [bmim][Tf2N] room-temperature ionic liquid, we use a non-polarizable all-atom force field with the partial atomic charges based on ab initio calculations for the isolated ion pair. The net charges of the ions are ±0.89e, which mimics the anion to cation charge transfer and polarization effects. The OPLS-AA force field is employed for modeling of n-hexane. The surface tension is computed using the mechanical route and its value decreases with increase of the n-hexane surface density. The [bmim][Tf2N]/n-hexane interface is analyzed using the intrinsic method, and the structural and dynamic properties of the interfacial, sub-interfacial, and central layers are computed. We determine the surface roughness, global and intrinsic density profiles, and orientation ordering of the molecules to describe the structure of the interface. We further compute the survival probability, normal and lateral self-diffusion coefficients, and re-orientation correlation functions to elucidate the effects of n-hexane on dynamics of the cations and anions in the layers.

  8. Cellulose nanocrystals' production in near theoretical yields by 1-butyl-3-methylimidazolium hydrogen sulfate ([Bmim]HSO4)-mediated hydrolysis.

    Science.gov (United States)

    Mao, Jia; Heck, Barbara; Reiter, Günter; Laborie, Marie-Pierre

    2015-03-06

    We report on near theoretical yield production of cellulose I nanocrystals (CNCs) using a two-step hydrolysis with the mildly acidic ionic liquid (IL) 1-butyl-3-methylimidazolium hydrogen sulfate ([Bmim]HSO4) in aqueous solution from common cellulosic sources. Two successive Taguchi experimental plans were performed to evaluate the impact of selected reaction parameters (T, t, H2O:IL ratio) and their interactions on the CNCs' yield from bleached softwood kraft pulp (SWP), bleached hardwood kraft pulp (HWP) and microcrystalline cellulose (MCC). With these experimental plans, the molar yield for extraction of nanocrystals was optimized to near theoretical levels, reaching 57.7±3.0%, 57.0±2.0%, and 75.6±3.0%, for SWP, HWP and MCC, respectively. The reaction yields corresponded to a relative crystalline region recovery of 84.1±5.3%, 71.7±1.3%, 76.0±2.0% from SWP, HWP and MCC, respectively. The collected nanocrystals exhibited high aspect ratios (36-43), negligible sulfur content (0.02-0.21%) and high solvent dispersibility in comparison to those obtained with the traditional sulfuric acid method. Additionally these near theoretical yields were achieved for mild reaction conditions with the combined severity factor of 2 and 3 for MCC and pulp, respectively. Overall this two-stage IL-mediated preparation of nanocrystals combines the advantages of achieving high product quality, high reaction yields and mild conditions.

  9. Molecular dynamics simulations of n-hexane at 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide interface

    Energy Technology Data Exchange (ETDEWEB)

    Lisal, Martin [Institute of Chemical Process Fundamentals of the ASCR, v. v. i., 165 02 Prague 6-Suchdol (Czech Republic); Department of Physics, Faculty of Science, J. E. Purkinje University, 400 96 Usti n. Lab. (Czech Republic); Izak, Pavel [Institute of Chemical Process Fundamentals of the ASCR, v. v. i., 165 02 Prague 6-Suchdol (Czech Republic)

    2013-07-07

    Molecular dynamics simulations of n-hexane adsorbed onto the interface of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide ([bmim][Tf{sub 2}N]) are performed at three n-hexane surface densities, ranged from 0.7 to 2.3 {mu}mol/m{sup 2} at 300 K. For [bmim][Tf{sub 2}N] room-temperature ionic liquid, we use a non-polarizable all-atom force field with the partial atomic charges based on ab initio calculations for the isolated ion pair. The net charges of the ions are {+-}0.89e, which mimics the anion to cation charge transfer and polarization effects. The OPLS-AA force field is employed for modeling of n-hexane. The surface tension is computed using the mechanical route and its value decreases with increase of the n-hexane surface density. The [bmim][Tf{sub 2}N]/n-hexane interface is analyzed using the intrinsic method, and the structural and dynamic properties of the interfacial, sub-interfacial, and central layers are computed. We determine the surface roughness, global and intrinsic density profiles, and orientation ordering of the molecules to describe the structure of the interface. We further compute the survival probability, normal and lateral self-diffusion coefficients, and re-orientation correlation functions to elucidate the effects of n-hexane on dynamics of the cations and anions in the layers.

  10. Electrodeposition and magnetic characterization of iron and iron-silicon alloys from the ionic liquid 1-butyl-1-methylpyrrolidinium trifluoromethylsulfonate.

    Science.gov (United States)

    Giridhar, Pulletikurthi; Weidenfeller, Bernd; El Abedin, Sherif Zein; Endres, Frank

    2014-11-10

    The electrodeposition of soft magnetic iron and iron-silicon alloys for magnetic measurements is presented. The preparation of these materials in 1-butyl-1-methylpyrrolidinium trifluoromethylsulfonate, [Py1,4]TfO, at 100 °C with FeCl2 and FeCl2 +SiCl4 was studied by using cyclic voltammetry. Constant-potential electrolysis was carried out to deposit either Fe or FeSi, and deposits of approximately 10 μm thicknesses were obtained. By using scanning electron microscopy and X-ray diffraction, the microstructure and crystallinity of the deposits were investigated. Grain sizes in the nanometer regime (50-80 nm) were found and the presence of iron-silicon alloys was verified. Frequency-dependent magnetic polarizations, coercive forces, and power losses of some deposits were determined by using a digital hysteresis recorder. Corresponding to the small grain sizes, the coercive forces are around 950-1150 A m(-1) and the power losses were at 6000 J m(-3), which is much higher than in commercial Fe(3.2 wt %)Si electrical steel. Below a polarization of 1.8 T, the power losses are mainly caused by domain wall movements and, above 1.8 T, by rotation of magnetic moments as well as domain wall annihilation and recreation.

  11. Synthesis, Characterization and Application of 1-Butyl-3 Methylimidazolium Chloride as Green Material for Extractive Desulfurization of Liquid Fuel

    Directory of Open Access Journals (Sweden)

    Swapnil A. Dharaskar

    2013-01-01

    Full Text Available The possible application of imidazolium ionic liquids as energy-efficient green material for extractive deep desulfurization of liquid fuel has been investigated. 1-Butyl-3-methylimidazolium chloride [BMIM]Cl was synthesized by nucleophilic substitution reaction of n-methylimidazolium and 1-chlorobutane. Molecular structures of the ILs were confirmed by FTIR, 1H-NMR, and 13C-NMR. The thermal properties, conductivity, solubility, water content and viscosity analysis of [BMIM]Cl were carried out. The effects of reaction time, reaction temperature, sulfur compounds, and recycling of IL without regeneration on dibenzothiophene removal of liquid fuel were presented. In the extractive desulfurization process, the removal of dibenzothiophene in n-dodecane using [BMIM]Cl was 81% with mass ratio of 1 : 1, in 30 min at 30°C under the mild reaction conditions. Also, desulfurization of real fuels with IL and multistage extraction were studied. The results of this work might offer significant insights in the perceptive use of imidazoled ILs as energy-efficient green material for extractive deep desulfurization of liquid fuels as it can be reused without regeneration with considerable extraction efficiency.

  12. Synthesis, characterization and application of 1-butyl-3 methylimidazolium chloride as green material for extractive desulfurization of liquid fuel.

    Science.gov (United States)

    Dharaskar, Swapnil A; Varma, Mahesh N; Shende, Diwakar Z; Yoo, Chang Kyoo; Wasewar, Kailas L

    2013-01-01

    The possible application of imidazolium ionic liquids as energy-efficient green material for extractive deep desulfurization of liquid fuel has been investigated. 1-Butyl-3-methylimidazolium chloride [BMIM]Cl was synthesized by nucleophilic substitution reaction of n-methylimidazolium and 1-chlorobutane. Molecular structures of the ILs were confirmed by FTIR, (1)H-NMR, and (13)C-NMR. The thermal properties, conductivity, solubility, water content and viscosity analysis of [BMIM]Cl were carried out. The effects of reaction time, reaction temperature, sulfur compounds, and recycling of IL without regeneration on dibenzothiophene removal of liquid fuel were presented. In the extractive desulfurization process, the removal of dibenzothiophene in n-dodecane using [BMIM]Cl was 81% with mass ratio of 1 : 1, in 30 min at 30°C under the mild reaction conditions. Also, desulfurization of real fuels with IL and multistage extraction were studied. The results of this work might offer significant insights in the perceptive use of imidazoled ILs as energy-efficient green material for extractive deep desulfurization of liquid fuels as it can be reused without regeneration with considerable extraction efficiency.

  13. The role of CT in evaluation of the effectiveness of embolisation of spinal dural arteriovenous fistulae with N -butyl cyanoacrylate

    Energy Technology Data Exchange (ETDEWEB)

    Cognard, C. [Service de Neuroradiologie Charcot, Hopital de la Salpetriere, Paris (France); Miaux, Y. [Service de Neuroradiologie Charcot, Hopital de la Salpetriere, Paris (France); Pierot, L. [Service de Neuroradiologie Charcot, Hopital de la Salpetriere, Paris (France); Weill, A. [Service de Neuroradiologie Charcot, Hopital de la Salpetriere, Paris (France); Martin, N. [Service de Neuroradiologie Charcot, Hopital de la Salpetriere, Paris (France); Chiras, J. [Service de Neuroradiologie Charcot, Hopital de la Salpetriere, Paris (France)

    1996-10-01

    A failed embolisation of a spinal dural arteriovenous fistula (AVF), because a pedicular injection has not reached the initial venous compartment, must be identified immediately, to allow prompt surgery and thus avoid clinical deterioration. The purpose of our study was to determine the role of CT in confirming a complete cure just after embolisation with N -butyl cyanoacrylate (NBCA). Seven patients embolised for spinal dural AVFs with perimedullary venous drainage had an immediate postembolisation CT scan. In six patients a complete cure was achieved, with a normal postembolisation angiogram in five cases. Just after injection of NBCA, we were unable to determine on plain films whether or not the glue had reached the draining vein in six of seven cases. The postembolisation CT showed various patterns: in two cured patients, the glue was visible in the inner surface of the dura mater and therefore on the venous side. In five cases, the glue was approaching the dura mater around the cord or seemed to reach its surface: in the four patients cured, the glue column was 7-18 mm high, whereas it was less than 2 mm high in the patient with angiographic proof of recurrent fistula. The follow-up angiogram remains the only way to confirm a durable cure. We suggest that immediate postembolisation CT may help in assessing endovascular treatment of spinal dural AVFs. (orig.). With 4 figs., 2 tabs.

  14. Crystal structure of trans-N,N′-bis(3,5-di-tert-butyl-2-hydroxyphenyloxamide methanol monosolvate

    Directory of Open Access Journals (Sweden)

    Miguel-Ángel Velázquez-Carmona

    2016-07-01

    Full Text Available The here crystallized oxamide was previously characterized as an unsolvated species [Jímenez-Pérez et al. (2000. J. Organomet. Chem. 614–615, 283–293], and is now reported with methanol as a solvent of crystallization, C30H44N2O4·CH3OH, in a different space group. The introduction of the solvent influences neither the molecular symmetry of the oxamide, which remains centrosymmetric, nor the molecular conformation. However, the unsolvated molecule crystallized as an ordered system, while many parts of the solvated crystal are disordered. The hydroxy group in the oxamide is disordered over two chemically equivalent positions, with occupancies 0.696 (4:0.304 (4; one tert-butyl group is disordered by rotation about the C—C bond, and was modelled with three sites for each methyl group, each one with occupancy 1/3. Finally, the methanol solvent, which lies on a twofold axis, is disordered by symmetry. The disorder affecting hydroxy groups and the solvent of crystallization allows the formation of numerous supramolecular motifs using four hydrogen bonds, with N—H and O—H groups as donors and the oxamide and methanol molecule as acceptors.

  15. Molecular dynamics simulations of n-hexane at 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide interface.

    Science.gov (United States)

    Lísal, Martin; Izák, Pavel

    2013-07-07

    Molecular dynamics simulations of n-hexane adsorbed onto the interface of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide ([bmim][Tf2N]) are performed at three n-hexane surface densities, ranged from 0.7 to 2.3 μmol/m(2) at 300 K. For [bmim][Tf2N] room-temperature ionic liquid, we use a non-polarizable all-atom force field with the partial atomic charges based on ab initio calculations for the isolated ion pair. The net charges of the ions are ±0.89e, which mimics the anion to cation charge transfer and polarization effects. The OPLS-AA force field is employed for modeling of n-hexane. The surface tension is computed using the mechanical route and its value decreases with increase of the n-hexane surface density. The [bmim][Tf2N]/n-hexane interface is analyzed using the intrinsic method, and the structural and dynamic properties of the interfacial, sub-interfacial, and central layers are computed. We determine the surface roughness, global and intrinsic density profiles, and orientation ordering of the molecules to describe the structure of the interface. We further compute the survival probability, normal and lateral self-diffusion coefficients, and re-orientation correlation functions to elucidate the effects of n-hexane on dynamics of the cations and anions in the layers.

  16. Individual or synchronous biodegradation of di-n-butyl phthalate and phenol by Rhodococcus ruber strain DP-2

    Energy Technology Data Exchange (ETDEWEB)

    He, Zhixing; Niu, Chengzhen; Lu, Zhenmei, E-mail: lzhenmei@zju.edu.cn

    2014-05-01

    Highlights: • A Rhodococcus ruber strain degraded DBP and phenol. • Degradation kinetics of DBP or phenol fit modified first-order models. • Degradation interaction between DBP and phenol was studied by strain DP-2. • The degradation genes transcriptional were quantified by RT-qPCR. - Abstract: The bacterial strain DP-2, identified as Rhodococcus ruber, is able to effectively degrade di-n-butyl phthalate (DBP) and phenol. Degradation kinetics of DBP and phenol at different initial concentrations revealed DBP and phenol degradation to fit modified first-order models. The half-life of DBP degradation ranged from 15.81 to 27.75 h and phenol degradation from 14.52 to 45.52 h under the initial concentrations of 600–1200 mg/L. When strain DP-2 was cultured with a mixture of DBP (800 mg/L) and phenol (700 mg/L), DBP degradation rate was found to be only slightly influenced; however, phthalic acid (PA) accumulated, and phenol degradation was clearly inhibited during synchronous degradation. Transcriptional levels of degradation genes, phenol hydroxylase (pheu) and phthalate 3,4-dioxygenase (pht), decreased significantly more during synchronous degradation than during individual degradation. Quantitative estimation of individual or synchronous degradation kinetics is essential to manage mixed hazardous compounds through biodegradation in industrial waste disposal.

  17. Effects of N-n-butyl Haloperidol Iodide on Myocardial Ischemia/Reperfusion Injury and Egr-1 Expression in Rat

    Institute of Scientific and Technical Information of China (English)

    Yan-Mei ZHANG; Gang-Gang SHI; Zhao TANG; Jin-Hong ZHENG; Wei-Qiu LI; Fu-Xiao GUO; Qiang-Yong JIA

    2006-01-01

    We have previously shown that N-n-butyl haloperidol iodide (F2) derived from haloperidol reduces ischemia/reperfusion-induced myocardial injury by blocking intracellular Ca2+ overload. This study tested the hypothesis that cardio-protection with F2 is associated with an attenuation in the expression of early growth response gene 1 (Egr-1). In an in vivo rat model of 60 min coronary occlusion followed by 180 min of reperfusion, treatment with F2 significantly reduced myocardial injury evidenced by the reduction in release of plasma creatine kinase, myocardial creatine kinase isoenzyme and lactate dehydrogenase. In cultured neonatal rat cardiomyocytes of hypoxia for 3 h and reoxygenation for 1 h, F2 treatment attenuated necrotic and apoptotic cell death, as demonstrated by electron microscopy. Concomitant with cardio-protection by F2, the increased expression levels of Egr-1 mRNA and proteinwere significantly reduced in myocardial tissue and cultured cardiomyocytes as detected by reverse transcription-polymerase chain reaction, immunohistochemistry and immunocytochemistry. In conclusion, these results suggest that the protective effect of F2 on ischemia/reperfusion- or hypoxia/reoxygenation-induced myocardial injury might be partly mediated by downregulating Egr-1 expression.

  18. Methyl tert-butyl ether (MTBE) in public and private wells in New Hampshire: Occurrence, factors, and possible implications

    Science.gov (United States)

    Ayotte, J.D.; Argue, D.M.; McGarry, F.J.; Degnan, J.R.; Hayes, L.; Flanagan, S.M.; Helsel, D.R.

    2008-01-01

    Methyl tert-butyl ether (MTBE) concentrations ???0.2 ??g/L were found in samples of untreated water in 18% of public-supply wells (n = 284) and 9.1% of private domestic wells (n = 264) sampled in 2005 and 2006 in New Hampshire. In counties that used reformulated gasoline (RFG), MTBE occurred at or above 0.2 ??g/L in 30% of public- and 17% of private-supply wells. Additionally, 52% of public-supply wells collocated with fuel storage and 71% of mobile home park wells had MTBE. MTBE occurrence in public-supply wells was predicted by factors such as proximity to sources of fuel, land use, and population density, as well as low pH and distance from mapped lineaments. RFG use, land-use variables, and pH were important predictors of private-well MTBE occurrence. Variables representing sources of MTBE, such as the distance to known fuel sources, were not significant predictors of MTBE occurrence in private-supply wells. It is hypothesized that private wells may become contaminated from the collective effects of sources in high population areas and from undocumented incidental releases from onsite or proximal gasoline use. From 2003 to 2005, MTBE occurrence decreased in 63 public-supply wells and increased in 60 private-supply wells, but neither trend was statistically significant. ?? 2008 American Chemical Society.

  19. n-Butyl benzyl phthalate promotes breast cancer progression by inducing expression of lymphoid enhancer factor 1.

    Directory of Open Access Journals (Sweden)

    Tsung-Hua Hsieh

    Full Text Available Environmental hormones play important roles in regulating the expression of genes involved in cell proliferation, drug resistance, and breast cancer risk; however, their precise role in human breast cancer cells during cancer progression remains unclear. To elucidate the effect of the most widely used industrial phthalate, n-butyl benzyl phthalate (BBP, on cancer progression, we evaluated the results of BBP treatment using a whole human genome cDNA microarray and MetaCore software and selected candidate genes whose expression was changed by more than ten-fold by BBP compared with controls to analyze the signaling pathways in human breast cancer initiating cells (R2d. A total of 473 genes were upregulated, and 468 were downregulated. Most of these genes are involved in proliferation, epithelial-mesenchymal transition, and angiogenesis signaling. BBP induced the viability, invasion and migration, and tube formation in vitro, and Matrigel plug angiogenesis in vivo of R2d and MCF-7. Furthermore, the viability and invasion and migration of these cell lines following BBP treatment was reduced by transfection with a small interfering RNA targeting the mRNA for lymphoid enhancer-binding factor 1; notably, the altered expression of this gene consistently differentiated tumors expressing genes involved in proliferation, epithelial-mesenchymal transition, and angiogenesis. These findings contribute to our understanding of the molecular impact of the environmental hormone BBP and suggest possible strategies for preventing and treating human breast cancer.

  20. Vapor-Liquid Equilibrium Measurements and Modeling for Ternary System Water + Ethanol + 1-Butyl-3-methylimidazolium Acetate

    Institute of Scientific and Technical Information of China (English)

    D.ENG Dongshun; WANG Rufa; ZHANG Lianzhong; GE Yun; JI Jianbing

    2011-01-01

    Vapor-liquid equilibrium(VLE) data were measured for ternary system water + ethanol + 1-butyl-3methylimidazolium acetate([bmim][OAc]),in a relatively wide range of ionic liquid(IL) mass fractions up to 0.8.Six sets of complete T-x-y data were obtained,in which the mole fraction of ethanol on IL-free basis was fixed separately at 0.1,0.2,0.4,0.6,0.8,and approximate 0.98.The non-random-two-liquid(NRTL) and electrolyte non-random-two-liquid(eNRTL) equations were used for correlation,showing similar deviations.The ternary VLE was also modeled with the correlation from two data sets,with the mole fractions of ethanol on IL-free basis being 0.1 and approximate 0.98.The VLE data were also reproduced satisfactorily.With the eNRTL model,the root-mean-square deviation for temperature is 0.79K and that for vapor-phase mole fraction is 0.0094.The calculations are in good agreement with experimental data.The effect of the IL on the VLE behavior of the volatile components is also illustrated.