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EN
The aim of the study was to determine fluoride content in sand from sandboxes in Police town (West Pomerania, Poland). This area is exposed to excessive emissions of fluoride compounds because of the proximity of chemical plants. The sand samples were collected five times in a period from March to November in 2016. Fluoride content was determined using the potentiometric method with an ion-selective fluoride electrode. The obtained results showed that fluoride content was ranged from 0.09 to 1.48 mg·kg-1 dm. The lowest fluoride content was recorded in the sand collected in place, which was the closest to the emitter, and the largest in the samples from sandbox, which was furthest from the emitter. Analyzing the changes in the content of this element over time, the largest fluoride concentration of sand occurred in July or September depending on location. Pearson correlation coefficient at p < 0.05 (r = 0.925) showed a significant positive correlation between fluoride content and the distance from fluoride emitter.
EN
Suppressed ion chromatography with a highly selective and high capacity anion-exchange column is used for the determination of anionic compounds in ten commercially available toothpastes. Minimal sample preparation is needed, requiring only dilution and filtration over a solid-phase extraction cartridge. Quantitative analysis of fluoride and monofluorophosphate, as well as chloride, nitrate, orthophosphate, and sulfate is achieved in one chromatographic run with a total analysis time of 25 minutes. Optimized analytical conditions are validated in terms of accuracy, precision, and total uncertainty, and the results demonstrate the reproducibility of ion chromatography. The coefficient of determination for the anions ranges from 0.9896 to 0.9997. The spiked recoveries for the anions are 88–108%. The change in the fluoride content of the toothpaste with storage time is investigated.
EN
Fluorine and sodium chloride are common elements present in the water environment. According to WHO guidelines fluoride content in water cannot be not higher than 1.5 mF-/dm3. Elevated fluoride content was observed all over the world and it leads to many health issues. It can be removed with the usage of various methods (ion exchange, membrane processes, adsorption, precipitation). In this paper fluoride removal with nanofiltration usage was described. Tests were performed with the application of Amicon 86400 filtration cells. Two types of commercial nanofiltration membranes NP010P and NP030P (Microdyn Nadir) were used. Transmembrane pressure was established as 0.3 MPa. For lower fluoride concentrations (5 mgF-/dm3) NF process allowed to decrease fluoride content under level 1.5 mgF-/dm3. Removal efficiency decreased with increasing fluoride content. Membrane NP030P showed better separation properties. Sodium chloride influenced removal efficiency as well as fluoride adsorption on/in membranes during the process. According to obtained data, better hydraulic properties exhibited membrane NP010P. For both membranes decrease in permeate flux in comparison to pure water was noticed what was observed. Relative permeability was lowered even to 0.32.
EN
Fluoride is regarded as one of the strongest oxidants, which causes oxidative changes in cells of living organisms. It may both increase the content of reactive oxygen species and inhibit the activity of antioxidative enzyme. In recent years, many researchers successfully used the properties of clay minerals in the sorption of fluoride ion from water. This raises the question of the possibility of limiting the effect of fluorine on the negative changes in plants by adding bentonite to soil. A two-year pot experiment was carried out in the Greenhouse of West Pomeranian University of Technology in Szczecin, on loamy sand and sandy loam. Each sample of soil was mixed with three different concentrations of bentonite – 1, 5, 10% of dry weight (DW) of the soil and then treated with 30 mmol of F- per 1 kg of dry weight of the soil in a form of NaF solution. A control series was prepared for each soil, to which no additives were added. The medium prepared in such way was transferred to plastic pots (3 kg each) and seeded with 16 pea seeds of Pisum sativum. In three phases of pea development (4 leaves unfolded, flowering and development of fruit), fresh leaf samples were collected and the concentrations of ascorbic acid, reduced glutathione, total flavonoids and total polyphenols were measured. Sodium fluoride introduced to the soil changed the level of antioxidant parameters in the plant, which may suggest that fluoride is involved in the formation of reactive oxygen species, resulting in oxidative stress. Bentonite in a dosage of 10% reduced the toxic effects of fluoride on the oxidative balance and morphological changes in the plant, which was observed especially for loamy sand, naturally poor in clay minerals.
5
Content available remote Growth and scintillation propertiesof Ce-doped PrF₃ single crystals
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EN
The scintillation characteristics of the Ce-doped PrF₃ single crystals have been studied to find out their potential as for heavy scintillators. Crystal growth was performed in a vacuum-tight micro-pulling down (µ-PD) system. PrF₃ crystal was prepared with various concentrations (0, 0.1, 0.5, 1, 3, 5, 10, 20, 60, 80, 100%) of Ce³⁺. The crystals were transparent (CeF₃) or of greenish colour, 3 mm in diameter and 15-50 mm in length. Neither visible inclusions nor cracks were observed. At room temperature, the radio- and photoluminescence spectra and the decay kinetics were measured for the sample set.
PL
W pracy przedstawiono formowanie nanorurek TiO2 na stopie Ti-6Al-7Nb w 1M H3PO4z dodatkiem niewielkich ilości jonów fluorkowych. Na jakość otrzymywanych przez anodowanie nanorurek wpływają parametry takie jak: potencjał, czas anodowania, stężenie jonów fluorkowych w roztworze, szybkość narastania potencjału, przy czym wartości dwóch ostatnich parametrów wydają się być kluczowymi i odpowiedzialnymi za morfologię oraz strukturę otrzymywanych warstw. W badaniach skoncentrowano uwagę na wpływie jonów fluorkowych na przebieg anodowania dwufazowego stopu implantowego (α+β) Ti-6Al-7Nb. Proces formowania polegał na polaryzacji próbek do 20 V z szybkością narastania potencjału 500 mV/s w 1M H3PO4z dodatkiem 0,2; 0,3; 0,4% wag. HF, oraz utrzymaniu próbki w tych warunkach przez 2h. W rezultacie otrzymano powierzchnię nanorurek o średnicach od 50 do 80 nm na fazie α oraz o grubszych ściankach na fazie β. Proces elektrochemicznego formowania obejmował dwa etapy: pierwszy potencjodynamiczny oraz drugi potencjostatyczny (20 V).Podczas ich trwania zarejestrowano różne charakterystyki prądowe dla opisywanych stężeń jonów fluorkowych. Z przeprowadzonych badań wynika jednoznaczna zależność pomiędzy najwyższą wartością prądu zarejestrowaną w etapie potencjodynamicznym a średnicą nanorurek otrzymywanych podczas anodowania przy udziale 0,3% wag. HF, fakt ten jest tłumaczony obecnością pierwiastków stopowych oraz transportem jonów w warstwie tlenkowej.
EN
The formation of nanotube oxide layers on Ti-6Al-7Nb alloy in H3PO4 acid solutions containing fluoride ions is presented. Among several parameters influencing the quality of nanotubes formed anodically such as potential, time of anodizing, fluoride ions concentration and scan rate of polarization, particularly the last two seem to be the most responsible for nanotubes structure and morphology. The effect of fluoride ions concentration on the morphology of nanotubes on the two phase (α+β) Ti-6Al-7Nb implant alloy has been evaluated in our work. The formation of nanotubes was performed by polarizing of the Ti-6Al-7Nb alloy samples in 1M H3PO4containing 0.2, 0.3 and 0.4 wt% HF to 20 V using scan rate 500 mV/s and then holding them at that potential for further 2h in the same electrolyte. Nanotubes of diameter ranging from 50 nmto 80 nm, with thicker walls over β-phase grains than over α-phase grains, were obtained. During the formation process, which includes two stages: the first potentiodynamic and the second potentiostatic (20 V),different electrochemical behaviour was observed in electrolytes of various fluoride concentration. The clear relationship between the highest currents and the biggest diameter of nanotubes for 0.3 wt% HF containing electrolyte observed during the first stage of anodizing is explained with regard to electrochemical characteristics of alloying elements and transport of electrolyte anions in oxide layers.
EN
Fluorine is a common chemical element. According to WHO guidelines, the F- ion content in drinking water cannot be higher than 1.5 mg/dm3. Excess of fluorine leads to many health problems: Alzheimer’s disease, neurological disorders or fluorosis (dental or skeletal). Fluoride can be removed from aqueous solutions by means of various methods (adsorption, precipitation, ion-exchange or membrane techniques). The aim of this paper was to evaluate the efficiency of electrodialysis in fluoride removal under the presence of organic substances. During experiments solutions containing fluorides (5, 10, 100 and 200 mg F-/dm3), mineral salt (0.5 g NaCl/dm3) and organic matter (5, 10 and 15 mg/dm3 of humic acids) were used. The research was conducted with the use of the PC Cell BED-1 System. The current density was equal to 1.72 mA/cm2. It has been shown that electrodialysis is an efficient technique of fluoride removal provided that the initial concentration of F- ions is not higher than 10 mg F-/dm3. The impact of organic matter on the process run and efficiency was dependent on the fluoride content in the treated solution.
PL
Fluor jest powszechnie występującym pierwiastkiem chemicznym. Zgodnie z wytycznymi WHO zawartość fluorków w wodzie do picia nie może być większa niż 1.5 mg/dm3. Nadmiar fluoru prowadzi do licznych problemów zdrowotnych (Alzheimer, problemy neurologiczne, fluoroza zębów lub szkieletu). Fluorki mogą być usunięte z roztworów wodnych z wykorzystaniem różnych metod (adsorpcja, strącanie, wymiana jonowa czy procesy membranowe). Celem pracy była ocena efektywności elektrodializy w usuwaniu jonów fluorkowych w obecności substancji organicznych. W trakcie doświadczeń zostały wykorzystane roztwory zawierające fluorki (5, 10, 100 i 200 mg F-/dm3), sól mineralną (0.5 g NaCl/dm3) oraz substancje organiczne (5, 10 i 15 mg/dm3 kwasów humusowych). Doświadczenia zostały przeprowadzone z wykorzystaniem instalacji PCCell BED-1 System. Gęstość prądu wynosiła 1.72 mA/cm2. Wykazano, że w procesie elektrodializy fluorki są skutecznie usuwane pod warunkiem, że ich początkowe stężenie nie przekracza 10 mg F-/dm3. Wpływ substancji organicznych na przebieg i efektywność procesu zależał od stężenia fluorków w oczyszczanym roztworze.
EN
The density functional theory, supported with a commercial software, was used to compute the geometry and surface energy of fluorite cleaved along the (111), (110) and (100) planes. In the case of cleaving a piece of fluorite along the (111) plane the two newly created surfaces are identical consisting of fluorite ions with the surface energy equal to 0.384 J/m2. Cleaving fluorite along the (110) plane also provides identical halves and, both contain one Ca ion next to two F ions, with the surface energy equal to 0.723 J/m2. When cleaving takes place along the (100) plane, it creates two corresponding halves with different surface structures. One half, having only surface Ca ions (100Ca) has the surface energy equal to 0.866 J/m2, while the surface energy of the second half, having only F surface ions (100F), is 0.458 J/m2. Different structures and energies of the corresponding fluorite surfaces, that is (100Ca) and (100F) planes, should have an impact on their chemical properties, including hydrophobicity expressed by contact angle. The calculations performed in the paper also showed that reorganization of fluorite surfaces after cleaving was insignificant for all of the investigated planes.
EN
The influence of fluoride on tooth germ development, especially mineralised tissue, is well documented in numerous dental publications, but there are few reports concerning the influence of fluoride on enamel organ and dental papilla cells. The aim of the study was to assess histologically the development of tooth germs of 20-day-old rat foetuses whose mothers drank water without fluoride or with low (10 mg) and high (110 mg) contents of natrium fluoride, starting from the 12th day of the pregnancy. The fluoride contained in drinking water in low as well as high concentration accelerated the development of enamel organ and dental papilla structures in rat foetuses. The acceleration was proportional to the content of fluoride in drinking water. No disturbances caused by high concentration of natrium fluoride were observed.
EN
The aim of this study was (a) to determine the concentration of fluoride and cadmium in urine of 1240 children ( 635 boys, 605 girls) from Gdańsk, aged 7-14; and (b) to examine whether a correlation exists between age and sex of children, the location of the schools, and the urinary levels of fluoride and cadmium. Fluoride was determined potentiometrically using a fluoride-specific electrode. Cadmium was determined by atomic absorption spectrometry. The mean fluoride concentration in urine in children attending two schools located close to a phosphate fertilizer waste disposal site was 2.14 ± 1.16 mg F¯/L, in three others 1.05 ± 0.49 mg F¯/L. The mean cadmium concentration in urine was 0.17 ± 0.19 μg Cd/L. In children aged 7 the cadmium concentration was significantly lower than in older ones.
EN
Fluoride alters the expression and post-translational modifications of extracellular matrix proteins in dentin. The aim of our study was to determine the effects of fluoride on type I collagen expression during the early stages of tooth germ development in rats. Pregnant dams were divided into three groups and fed a standard diet. From the fifth day of pregnancy the three groups received tap water with, respectively, trace amounts of fluoride (C), a low fluoride concentration (FL) or and a high fluoride concentration (FH). Changes in type I collagen expression and distribution were evaluated. The expression of type I collagen was restricted to the extracellular spaces of cells of mesenchymal origin. In the youngest animals the most intense immunoreactivity for type I collagen was detected in predentin of the FL group. Although the intensity of immunostaining increased in proportion to the age of the animals, the largest increase in the groups investigated was detected in the FL group. We concluded that a low concentration of fluoride can act as a stimulator of type I collagen deposition in the extracellular matrix of dentin, while high concentrations of fluoride have an opposite effect, acting as an inhibitor of type I collagen formation in dentin.
EN
The fluoride concentrations in urine and water samples were measured potentiometri-cally with use of a selective fluoride electrode. Influence of fluoride content in drinking water on its level in urine of pre-school children was estimated. Statistical evaluation of the results obtained using different techniques of quantitative determination (direct reading, standard addition, double standard addition and bracketing solutions) was also carried out.
PL
Oznaczono stężenia jonów fluorkowych w wielu próbkach moczu i wody stosując metodę potencjometryczną z wykorzystaniem selektywnej elektrody fluorkowej. Oszacowano wpływ zawartości fluorków w wodzie pitnej na ich zawartość w moczu przedszkolaków. Przeprowadzono statystyczną ocenę wyników uzyskanych za pomocą różnych technik ilościowego oznaczania (bezpośredni odczyt, metoda dodatków, metoda podwójnego dodatku wzorca, metoda roztworów ograniczających).
PL
Doświadczenie przeprowadzono w warunkach laboratoryjnych na dwóch glebach o składzie granulometrycznym: piasku gliniastym (Corg 8.71 g/kg, pHKCl 6.36) i gliny lekkiej (Corg 10.92 g/kg, pHKCl 6.81). Do próbek gleb wprowadzono dwie ciecze jonowe: tetrafluoroboran 1-butylo-3-metyloimidazoliowy [BMIM][BF4] oraz tetrafluoroboran 1-heksylo-3-metyloimidazoliowy [HMIM][BF4] w dawkach: 0, 5, 50, 500 oraz 5000 mg/kg s.m. gleby. W 1., 7., 14., 28. i 56. dniu doświadczenia oznaczono chromatograficznie zawartość kationów imidazoliowych, potencjometrycznie zawartość fluoru rozpuszczalnego i potencjalnie dostępnego dla roślin oraz spektrofotometrycznie aktywność oksydazy o-difenolowej. Otrzymane wyniki wykazały, że kation [BMIM] okazał się układem odpornym na degradację w glebie, podczas gdy wydłużenie podstawnika alkilowego do sześciu atomów węgla zdecydowanie przyspieszyło proces zanikania. Zawartość fluoru rozpuszczalnego w roztworze glebowym, jak i potencjalnie dostępnego dla roślin, w glebie zanieczyszczonej imidazoliowymi cieczami jonowymi, zwiększała się w trakcie trwania doświadczeń. Natomiast zmiany aktywności oksydazy o-difenolowej w glebie zanieczyszczonej analizowanymi cieczami jonowymi zależne były od dawki oraz rodzaju cieczy jonowej, a także właściwości gleby.
EN
The experiment was carried out on two soil samples with granulometric composition: loamy sand (Corg 8.71 g/kg, pHKCl 6.36) and sandy loam (Corg 10.92 g/kg, pHKCl 6.81). Two ionic liquids: 1-butyl-3-methylimidazolium tetrafluoroborate [BMIM][BF4] and 1-hexyl-3-methylimidazolium tetrafluoroborate [HMIM][BF4] at dosages of: 0, 5, 50, 500, and 5000 mg/kg dm. were applied into soil. On days 1, 7, 14, 28, and 56 content of imidazolium cations, two forms of fluoride (soluble and potentially available to plants) and activity of o-diphenol oxidase were determined by chromatographic, potentiometric, and spectophotometric methods, respectively. Obtained results showed that the [BMIM] cation was resistant to degradation in the soil, while lengthening the alkyl substituent six carbon strongly accelerated the process of decomposition. Soluble and potentially available to plants fluoride content in the soil with imidazolium ionic liquids, increased during the experiments. Changes of o-diphenol oxidase activity in soil with imidazolium ionic liquids: with tetrafluoroborate anion were dependent on the dose and the type of ionic liquid, and the soil properties.
PL
Omówiono problem usuwania związków fluoru z gazów metalurgicznych bogatych w SO2, kierowanych do utylizacji w fabrykach kwasu siarkowego. Przedstawiono wyniki badań w skali laboratoryjnej oczyszczania gazów z HF z zastosowaniem różnych sorbentów. Dla każdego z testowanych sorbentów wyznaczono skuteczności usuwania fluorowodoru i pojemności sorpcyjne.
EN
The paper describes the problem of fluorine compounds removal from SO2-rich metallurgical off-gases, directed for utilisation in the sulphuric acid plants. Results of laboratory-scale investigation on HF removal process with the use of different types of absorbents are presented. The process efficiency and the sorptive capacity of each tested absorbent have been determined.
EN
The study was conducted on 40 women in the early postmenopausal period, aged 52.3±3.1 years with primary osteoporosis unmanageable in treatment, divided into 2 groups based on a randomized list. Group I (n-20) was administered orally fluoride 0.25 mg kg-1 24 h-1 with modified transdermal hormone therapy/HRT, and group II (n-20) was administered orally fluoride and supplement hormonal therapy(HST) in 21 therapeutic cycle. The serum concentrations of osteocalcin (OC), procollagen(PICP), insulin-like growth factor I (IGF-1), prolactin basic (PRL) and prolactin after metoclopramide (PRL/ MCP) 4 times by using radioimmunoassy methods, before treatment and after 1, 3, 12 months of treatment. Bone mineral density (BMD) L2 – L4 was determined before treatment and at 12 month with a dualenergy x-ray absorptiometry scanner (Lunar DPX-1Q). In group I women receiving fluoride and transdermal HRT IGF-1 increased significantly while the concentrations of OC and PICP significantly decreased after 3 and 12 months of treatment but no statistically significant changes in the PRL concentration occurred. In group II women receiving orally fluoride and HST, a significant decrease in the concentration of IGF-1, OC after 3 and 12 months and a significant increase in the concentration of PRL and PRL/ MCP after 1, 3 and 12 months of treatment compared with the baseline values appeared. The concentration of type I procolagen (PICP) showed no statistically significant changes. Increase in bone mineral density was statistically significant L1, L2 (p < 0.05), L3, L4 (p < 0.01) compared with the baseline in the group receiving transdermal HRT. In women receiving fluoride and orally HST increase in the bone mineral density for L1 and L2 was non-insignificant, whereas for L3 and L4 it was significantly higher compared with the baseline (p < 0.05).
PL
Badaniem objęto 40 kobiet we wczesnym okresie pomenopauzalnym, w wieku 52,3±3,1 lat, podzielonych wg listy randomizowanej na dwie grupy: grupę I. (n-20) otrzymującą doustnie fluor w dawce 0,25 mg kg-1 24 h-1 oraz zmodyfikowaną przezskórną hormonoterapię zastępczą (HTZ), grupę II (n-20) otrzymującą doustnie fluor w dawce 0,25 mg kg-1 24 h-1 i hormonoterapię wspomaganą (HTW) w postaci tabletek. Cykle terapeutyczne w obu grupach trwały 21 dni w miesiącu z następową przerwą 7 dni w celu wystąpienia krwawienia z odstawienia przez okres jednego roku. W surowicy oceniano stężenia osteokalcyny (OC), prokolagenu (PICP), insulinopodobnego czynnika wzrostu (IGF-1), podstawową prolaktynę (PRL) i po teście z metoklopramidem (PRL/MCP) radioimmunologicznie czterokrotnie: przed leczeniem oraz po 1. 3. i 12. miesiącu leczenia. Gęstość mineralną trzonów kręgów lędźwiowych L2 –L4 badano przed leczeniem i po 12 miesiącach leczenia densytometrem, firmy Luna (DPX-1Q), metodą DEXA. U kobiet z grupy I otrzymującej doustnie fluor i przezskórnie HTZ wystąpił znamienny wzrost stężenia IGF-1, znamienne obniżenie OC, PLCP po 3 i 12 miesiącach leczenia oraz brak statystycznych zmian w stężeniu prolaktyny. Natomiast u kobiet z grupy II otrzymującej w postaci tabletek doustnie fluor i hormonoterapię wspomaganą HTW wystąpiło znamienne obniżenie stężeń IGF-1, OC po 3 i 12 miesiącach leczenia oraz znamienny wzrost stężenia prolaktyny podstawowej i po teście z metoklopramidem po 1. 3. i 12. miesiącu leczenia w porównaniu z wartościami wstępnymi. Stężenia prokolagenu w czasie stosowania doustnie fluoru i HTW nie wykazywały znamiennych różnic. Gęstość mineralna L2-L4 wykazywała znamienne przyrosty u kobiet z grupy I. Natomiast u kobiet z grupy II gęstość mineralna L1, L2 nie wykazywała przyrostu znamiennego, a w kręgu L3, L4 występował znamienny przyrost w porównaniu z wartościami wyjściowymi (p < 0,01).
EN
One of the technologies producing harmful for the environment wastes containing fluorine compounds is aluminium metallurgy. The surroundings of the Aluminium Metallurgy Plant in Skawina were characterised by significant pollution of all the environmental components with fluorine compounds. The deposited wastes distinctly influenced the pollution of underground and surface waters. In underground waters the fluorine content exceeded the concentration in the unchanged areas even up to 200 times. The carried out reclamation work on the repository improved the aesthetic values of this area, but did not decrease threat for was. Harmful effects of waste deposition will still be visible for many years.
PL
Jedną z technologii, która wytwarza szkodliwe dla środowiska odpady zawierające związki fluoru, jest hutnictwo aluminium. Rejonem charakteryzującym się znacznymi zanieczyszczeniami związkami fluoru wszystkich komponentów środowiska było otoczenie Huty Aluminium w Skawinie. Składowane odpady wyraźnie wpłynęły na zanieczyszczenie wód podziemnych i powierzchniowych. W wodach podziemnych stwierdza się nawet dwustukrotne przekroczenia zawartości fluoru w stosunku do koncentracji w obszarach niezmienionych. Przeprowadzone prace rekultywacyjne na składowisku poprawiły walory estetyczne tego terenu, lecz nie zmniejszyły zagrożenia dla wód. Szkodliwe skutki nagromadzenia odpadów odczuwalne będą jeszcze przez wiele lat.
EN
Thirty groundwater samples were collected at the peak of the rainy season and analysed for fluoride and other cations and anions in drinking water sources of Langtang area. For comparative purposes, thirty seven groundwater samples were collected in the dry season. The aim of the study was to determine variation in fluoride content with respect to the seasons. Fluoride in water was determined by the Ion Selective Electrode (ISE) and the cations by the Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). The anion (sulphate) was determined by Multi – Ion Colorimeter, bicarbonate and chloride by titration method. In addition fluorine content in aquifer materials from a borehole section were determined by Fusion method. The two seasons show variation in content of fluoride in groundwater. Fluoride content in groundwater is higher in the dry season ranging from 0.13 – 10.3 mg/ l compared to the 0.06 – 4.60 mg/l values in the rainy season. Content of fluorine (0.01 wt %) in the aquifer materials (sands) is low from depth of 0 to 7.95 m. However, fluorine content increases with depth, from 7.95 to 10.60 m with concentration of 0.04 wt %, 0.05 wt % from 10.60 to 13.25m, and 0.07 wt % from 13.25 to 15.70 m, the content of fluorine however, decreased at depth 15.70 to18.55m with concentration of 0.02 wt % even with fluorite mineral in the aquifer material at this depth. Dilution of fluoride ion as a result of rain input which recharges the aquifer may be the main reason for lower values recorded in the rainy season. Over fifty and sixty percent of waters in both dry and rainy season have fluoride concentration above the WHO upper limit of 1.5 mg/l. Consumption of these elevated values of fluoride in groundwater of the study area, clearly manifests as symptoms of dental fluorosis.
EN
An examination was made of fluoride content in the mandibular first molars of the permanent teeth of the red fox Vulpes vulpes living in north-west (NW) Poland. The teeth were first dried to a constant weight at 105°C and then ashed. Fluorides were determined potentiometrically, and their concentrations were expressed in dry weight (DW) and ash. The results were used to perform an indirect estimation of fluoride pollution in the examined region of Poland. The collected specimens (n = 35) were classified into one of the three age categories: immature (im, 6–12 months), subadult (subad, from 12 to 20 months) and adult (ad, >20 months). The mean concentrations (geometric mean) of fluoride were similar in the im and subad groups (230 and 296 mg/kg DW and 297 and 385 mg/kg ash, respectively), and significantly smaller than in the ad group (504 and 654 mg/kg, respectively, in DW and ash). Basing on other reports that the ∼400 mg/kg DW concentration of fluoride in bones in the long-lived wild mammals generally reflects the geochemical background, it was found that 57% of the foxes in NW Poland exceeded this value by 9% to 170%. This indirectly reflects a moderate fluoride contamination in the tested region.
EN
A rapid spectrophotometric method employing the formation of a ternary complex of tin with Fe(II) and dimethylglyoxime, has been developed for the determination of tin in tantalum, iron and titanium bearing matrices. A novel method for the dissolution of samples has been proposed to avoid hydrolysis and subsequent loss of tin due to adsorption by the hydrolysed mass. The observation that Sn(IV) also forms a triple complex, besides Sn(II), with exactly overlapping spectra avoids the presence of tin in specific oxidation state. The molar absorptivity and the Sandell sensitivity of the complex formed at pH 0.8-2.0 in aqueous medium are 4.2 x 10(3) L mol(-1) cm'1 and 0.0242 ug cm(-2), respectively, in either oxi-dation state of Sn at absorption maximum 460 nm.
PL
Opracowano szybką metodę spektrofotometryczną oznaczania Sn w matrycach zawierających Ta, Fe i Ti. W metodzie wykorzystano powstawanie trój członowego kompleksu Sn(II) lub Sn(IV) z Fe(II). Kompleksy Sn(II) i Sn(lV) majądokładnie nakładające się widma z maksimum absorpcji przy 460 nm. Próbki rozpuszczono tak, aby nie powstawały osady zhydrolizowanych produktów, co eliminowało możliwość strat cyny wskutek adsorpcji na tych osadach. Wyznaczono molowy współczynnik absorpcji i czułość SandelPa dla trójczło-nowych kompleksów cyny; przy pH 0.8-2.0 wynosiły one odpowiednio 4.2x 10(3) L mol(-1) cm(-1) 0.0242 ug cm(-2).
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