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121.
Zoldoš Vlatka Vidaković-Cifrek Željka Tomić Mihovil Papeš Dražena 《Water, air, and soil pollution》1997,94(1-2):181-190
Allium test has already been used to determine cytotoxicity of waste drilling fluids. In the present work the cytotoxicity of four pure chemicals (Defoamex, Idthin 400, Magco Thin and Slick Pipe) was investigated. Those chemicals are components of drilling fluids, therefore, they are usually constituents of oil and gas industry waste waters. The tested chemicals were prepared in 1:9 dilution and cytotoxic effects on root-tip meristem ofAllium ascalonicum were analysed after 24-, 48- and 72-hour-treatments. All samples showed cytotoxicity which was proved by cytogenetic parameters such as inhibition of mitotic activity and increase of mitotic abnormalities and chromosomal aberrations in comparison with the control. Almost all mitotic abnormalities induced by four chemicals tested were the result of disturbed spindle mechanisms accompanied with stickiness. Slick Pipe revealed the most prominent mitodepressive effect and induced a high number of abnormalities. It caused a significant decrease of mitotic activity and increase of mitotic abnormalities after all three treatment durations, while chemicals Defoamex and Magco Thin showed a significant decrease of mitotic activity only after 72-hour-treatment. Chemicals Defoamex, Idthin 400 and Magco Thin revealed a significant increase of mitotic abnormalities after 48- and 72-hour-treatments. 相似文献
122.
The antiradical activities of some flavonols (kaempferol, quercetin, robinetin, quercetagetin, and myricetin), flavones (apigenin, baicalein, and luteolin), flavanones (naringenin and dihydroquercetin), and flavanols [(+)-catechin and (-)-epicatechin] were determined by measuring the reaction kinetics with 2,2-diphenyl-1-picrylhydrazyl (DPPH) and alpha,gamma-bisdiphenylene-beta-phenylallyl (BDPA) radicals. The reactions, which follow the mixed second-order rate law, were investigated under pseudo-first-order conditions by use of a large excess of flavonoids, and their stoichiometry was determined by spectrophotometric titration. The results confirm stoichiometric factors of 1, 2, and 3 for flavonoids with one, two, and three hydroxyl groups in the B-ring, respectively, excluding kaempferol, which, despite a single OH group in the B-ring, has a factor of 2, which is explained by the 3-OH group supporting the reaction with free radicals. Structure-activity considerations indicate for the present series of flavonoids the importance of multiple OH substitutions and conjugation. The logarithms of reaction rate constants with the OH, DPPH, and BDPA radicals correlate well with the reduction potential of the flavonoids. 相似文献
123.
Milisavljević MDj Timotijević GS Radović SR Brkljacić JM Konstantinović MM Maksimović VR 《Journal of agricultural and food chemistry》2004,52(16):5258-5262
An 8S storage globulin from buckwheat seed, which resembles the structure and features common to the vicilin-like family of seed storage proteins, was analyzed for this paper. It was found that expression of the 8S globulin gene precedes that of the 13S globulin (the main buckwheat storage protein) and starts from an early stage of buckwheat seed development (9-11 days after flowering), continuing to accumulate throughout seed development to contribute approximately 7% of total seed proteins. This protein fraction might be more interesting for biotechnological application than the 13S buckwheat legumin consisting of 23-25 kDa subunits reported to be the major buckwheat allergen. A partial cDNA was also isolated, showing high homology with cDNAs coding for vicilin-like storage proteins from various plant species, and its expression profile throughout seed development as well as in different buckwheat tissues was analyzed. 相似文献
124.
Vujcić Z Milovanović A Bozić N Dojnov B Vujcić M Andjelković U Loncar N 《Journal of agricultural and food chemistry》2010,58(22):11896-11900
Yeast cell wall invertase (CWI) was modified with dimethyl suberimidate, glutaraldehyde, formaldehyde, and sodium periodate. Retained activity after modification was 45% for CWI modified with formaldehyde, 77% for CWI modified with sodium periodate, 80% for CWI modified with glutaraldehyde, and 115% for CWI modified with dimethyl suberimidate. Chemically modified and native CWIs showed significantly broad pH stability (pH 3-11), whereas after incubations at 50, 60, and 70 °C, CWI modified with glutaraldehyde showed the highest thermostability. Optimum pH for CWI modified with glutaraldehyde was between 4 and 5, whereas optimum temperature was at 60 °C. Comparison to CWI modified with glutaraldehyde after immobilization within alginate beads showed broader pH optimum (4.0-5.5) as well as broader temperature optimum (55-70 °C). Column bed reactor packed with the immobilized CWI modified with glutaraldehyde was successfully used for the 95% inversion of 60% (w/w) sucrose at the flow rate of 3 bed volumes per hour, pH 4.9, and 45 °C. A 1 month productivity of 3844 kg of inverted sugar/kg of the immobilisate was obtained. 相似文献
125.
Nives Štambuk-Giljanović 《Water, air, and soil pollution》2010,211(1-4):49-60
The objective of the investigations of the Cetina River, located in southern Croatia, was to record specific characteristics and properties of the Cetina waters at nine stations. In addition to measurements undertaken in the Cetina River, the water quality of its most significant springs and tributaries, such as Kosinac, ?ilovka, Studenci and Mala Ruda, Velika Ruda and Grab, has also been measured. The water quality in the Cetina watershed has been evaluated in the following storage reservoirs: Peru?a, Bu?ko Blato and Pran?evi?i. The nitrogen compounds and phosphorus concentrations have been estimated at all these sampling sites over a 3-year period (2005–2008). Concentration levels at the Cetina-Vinali? sampling site for total N (from August 2005 to December 2008) ranged from 0 to 1.759 mg/L, for NH3–N from 0 to 0.374 mg/L, for NO3–N from 0.063 to 0.916 mg/L and for PO4–P from 0 to 0.099 mg/L. The results prove that the Cetina-Vinali? sampling site is not polluted by nitrogen and phosphorus compounds. The river section from Trilj to the Pran?evi?i dam, where the water is used for the water supply of Omi?, Makarska and Dalmatian islands, has been polluted by wastewater because the majority of agricultural area, roads, industry and settlements are located upstream of it. The highest concentration for total N of 1.128 mg/L and of 1,527 total coliforms in 100 mL, expressed as a mean value for a 3-year period of investigations, was found at the sampling site Trilj. The results of concentration changes at the ?ikotina La?a and Cetina Radmanove Mlinice sampling sites show no regularities. The highest concentration for total N of 0.941 mg/L was measured at the Cetina Radmanove Mlinice during 2007. The highest concentration for NO3–N of 0.916 mg/L was measured at the same sampling site. According to the investigations of the water quality of the Cetina springs and tributaries, the bacteriological most polluted river spring is Kosinac, and the bacteriological most polluted river tributary is Grab. With reference to the water quality in the Cetina storage reservoirs, it may be concluded that the lowest quality standard has been found within the Pran?evi?i storage reservoir regarding nitrogen compounds and phosphorus concentration levels. 相似文献
126.
B. K. Ilić 《Journal of pest science》1967,40(7):97-103
Summary This report is dealing with the fumigation of grain in granaries with phosphine against the main stored-grain insects in Yugoslavia. The phosphine gas was generated from PHOSTOXIN tablets which were inserted in the grain mass. The efficacy was tested by the mortality of laboratory-bred insects and insects of the natural infestation. The successful fumigation was depending on the temperature of the grain and of the storage rooms and on the exposure period. The covering of the grain mass by plastic sheets reduced the gas leakage considerably. The dosage of 5–6 tablets per ton of grain and an exposure time of 5 days resulted in a 100% mortality of all insect stages at a grain temperature of 19° C. In all trials the exposure time proved to be the main factor. For the control of the angoumois grain moth and the Indian meal moth in the storage rooms outside the grain mass an additional treatment with an insecticidal spray was necessary. The control of hot spots by inserting the tablets through a probe was successful, provided that these hot spots were not too numerous and could be marked off very accurately.
Die Übersetzung aus dem Jugoslawischen besorgte Herr Dipl.-Ing. MAYR, die Bearbeitung des deutschen Textes erfolgte durch Herrn. Dr. F. NEUBECKER; beide Deutsche Gesellschaft für Schädlingsbekämpfung m. b. H., Frankfurt a. M. 相似文献
Die Übersetzung aus dem Jugoslawischen besorgte Herr Dipl.-Ing. MAYR, die Bearbeitung des deutschen Textes erfolgte durch Herrn. Dr. F. NEUBECKER; beide Deutsche Gesellschaft für Schädlingsbekämpfung m. b. H., Frankfurt a. M. 相似文献
127.
128.
Results of field experiments designed to determine effects of acid treatment on pine forests are reported. ites were located at Lisselbo and Norrhden, Sweden. Acid treatments of sulphuric acid were combined with fertilizer treatments in order to identify possible effects of acidification on the forests. At the both sites N was found to be a factor limiting forest growth. The application of sulphuric acid resulted in a loss of much of the ground vegetation. No negative effects on the growth of the trees have been detected thus far. Results of lysimeter and soil incubation experiments indicate that even moderate additions of H2SO4 or S on the soil affect soil biological processes, particularly N turnover. 相似文献
129.
Photons are excellent information carriers but normally pass through each other without consequence. Engineered interactions between photons would enable applications as varied as quantum information processing and simulation of condensed matter systems. Using an ensemble of cold atoms strongly coupled to an optical cavity, we found that the transmission of light through a medium may be controlled with few photons and even by the electromagnetic vacuum field. The vacuum induces a group delay of 25 nanoseconds on the input optical pulse, corresponding to a light velocity of 1600 meters per second, and a transparency of 40% that increases to 80% when the cavity is filled with 10 photons. This strongly nonlinear effect provides prospects for advanced quantum devices such as photon number-state filters. 相似文献
130.
Grassino Antonela Ninčević Pedisić Sandra Dragović-Uzelac Verica Karlović Sven Ježek Damir Bosiljkov Tomislav 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(3):427-433
Plant Foods for Human Nutrition - In this paper, high-hydrostatic pressure extraction (HHPE) as an emerging food processing and preservation technique constitutes an alternative to conventional... 相似文献