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Wyszukujesz frazę "chromatography" wg kryterium: Temat


Tytuł:
Badania chromatograficzne produktów pirolizy granulatu ze zużytych opon
Chromatography investigations over wasted tyres granulate pyrolysis products
Autorzy:
Żmuda, W.
Budzyń, S.
Tora, B.
Tematy:
rubber pyrolisis
wasted tyres
chromatography
Pokaż więcej
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Powiązania:
https://bibliotekanauki.pl/articles/349577.pdf  Link otwiera się w nowym oknie
Opis:
Przemysł gumowy generuje znaczne ilości odpadów poprodukcyjnych i poużytkowych. Ostateczną formę i parametry użytkowe wyrobów uzyskuje się w nieodwracalnym procesie wulkanizacji. Dlatego też ponowne przetworzenie gumy wymaga kosztownych, praco- i czasochłonnych operacji umożliwiających jej destrukcję. Na ogół uzyskany recyrkulat ma gorsze własności fizykomechaniczne i jest niekonkurencyjny w stosunku do oryginalnych materiałów gumowych. W artykule przedstawiono wyniki analizy chromatograficznej produktów pirolizy odpadów gumowych.
Until the 1960s, rubber from scrap tires was routinely recycled, but that started to change as cheap oil imports - the raw material behind synthetic rubber - made reclaimed rubber less valuable, and the spread of steel belted tires made tire recycling more expensive, difficult and time-consuming. Scrap tires not only waste landfill space, they can damage the linings put in place to keep groundwater and surface water from mixing with land filled contaminants. In this paper it presents the results of chromatographic analysis of waste rubber pyrolisis.
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Concentration of some amino acids in blood plasma and study results of lumbosacral bone system computer tomography
Autorzy:
Wójcik, G.
Sokołowska, B.
Borzecki, A.
Tematy:
amino acids
chromatography
computed tomography
lumbar spine
Pokaż więcej
Wydawca:
Akademia Bialska Nauk Stosowanych im. Jana Pawła II w Białej Podlaskiej
Powiązania:
https://bibliotekanauki.pl/articles/2052367.pdf  Link otwiera się w nowym oknie
Opis:
Introduction and objective: Back pain are the most common ailment within the human locomotor system. Because of their prevalence, they were classified as diseases of civilization. The aim of the study was to attempt to assess the concentration of selected amino acids in plasma and correlating the results of laboratory tests with the occurrence of backaches. Material and method: The study group included 188 patients presenting for CT scan administering as the cause of their symptoms low back pains. All of these patients gave the blood samples from which the concentration of free amino acids was estimated by ion exchange chromatography using an automated amino acid analyzer AAA 400 from INGOS Praha. The control group consisted of patients who underwent testing using computed tomography and there were no primary or secondary changes associated with degeneration in the lumbar spine. Results: Patients on the basis of research carried out by computed tomography were divided into five groups according to disease entity. Analyzing the average concentration of essential amino acids in the blood plasma of patients of each group, it was found that it is higher in the case of lysine for each considered disease entity. The average concentration of methionine in all disease entities does not deviate from the average values in the control group. Analysis of the average concentration of selected essential amino acids revealed that in the case presented disorders underwent their level of variation. Average concentrations of selected amino acids have proven to be very similar in both groups. Slightly higher values proved to be in the control group for proline and lysine. Conclusions: The concentration of amino acids varies with the severity of degenerative changes in the connections as well as in interbody joints. The highest increase in the concentrations of all tested amino acids are present in root bands. Decrease in the concentrations of all tested amino acids appears in cancer.
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Applications of cytisine extraction and detection in biological materials for clinical medicine
Autorzy:
Bartusik-Aebisher, Dorota
Aebisher, David
Courtney, Ryan
Sobczak, Andrzej
Bober, Zuzanna
Podgórski, Rafał
Kołodziejczyk, Patrycjusz
Tutka, Piotr
Tematy:
smoking cessation
chromatography
Biomedicine
cytisine extraction
biopharmacy
Pokaż więcej
Wydawca:
Polskie Towarzystwo Farmaceutyczne
Powiązania:
https://bibliotekanauki.pl/articles/895314.pdf  Link otwiera się w nowym oknie
Opis:
Tobacco use is a leading cause of preventable mortality worldwide. New cost-effective smoking cessation treatments are needed especially in some low-to-middle income countries where smoking rates are rising, and current pharmacotherapy treatments remain cost-prohibitive. Since the 1960’s, cytisine has been used as an effective nicotine substitution agent to aid in smoking cessation albeit limited to a selected few Eastern/Central Europe and Central Asian countries. Cytisine is a biologically active alkaloid of plant origin and is known to be a ligand of nicotinic acetylcholinergic receptors (nAChRs). For several decades, the properties of cytisine have been investigated and reported in the biomedical and pharmaceutical literature. Due to the beneficial impact of cytisine on smoking cessation and its costly multistep synthesis, there is a growing interest in extraction from natural sources as well as in analytical identification and quantification for clinical medicine and forensic toxicology. In this paper, we present several current analytical approaches to cytisine extraction and identification from biological samples of plant and human origin. The development of extraction techniques will allow for the widespread use of the drug in experimental and clinical pharmacology, toxicology and forensic medicine.
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analyses of New Nontoxic Stabilizers and Other Components in Smokeless Powders
Autorzy:
Fryš, O.
Bajerová, P.
Eisner, A.
Ventura, K.
Skládal, J.
Tematy:
smokeless powders
chemical stabilizers
gravimetry
chromatography
infrared spectrometry
Pokaż więcej
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Powiązania:
https://bibliotekanauki.pl/articles/358010.pdf  Link otwiera się w nowym oknie
Opis:
Propellants consisting of nitrocellulose and/or other nitric esters are inherently chemically unstable and undergo decomposition even under standard storage conditions. Decomposition of such compounds can be inhibited or nearly stopped when stabilizers are used. However, conventional stabilizers form nitrosamines that have toxic and carcinogenic effects. A nitrocellulose based propellants contained new nontoxic stabilizers were prepared on this account. The new stabilizers are epoxidized oils (soybean oil, linseed oil and mixture fatty acids, C14-22). The chemical structure of the new stabilizers and their decomposition products should prevent the formation of toxic N-nitrosamines. We prepared double base propellants and these powders were investigated using Microcalorimetry, Conventional Stability Tests and Sensitivity Tests. The results were compared with propellants containing the conventional stabilizer akardite II. Qualitative and quantitative analyses were also performed. These analyses are very important next to the Conventional Stability Tests and Sensitivity Tests. Therefore, this paper presents qualitative and quantitative analyses results of the new substances as stabilizers for propellants. We studied options of oils stabilizers determination and mechanism of stabilization of propellants by oils. Paper describes quantitative analyses results of other substances in propellants (nitroglycerin and solvents) too and options of samples modifcation before analyses.
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Isolation and partial purification of anticoagulant fractions from the venom of the Iranian snake Echis carinatus
Autorzy:
Babaie, Mahdi
Zolfagharian, Hossein
Salmanizadeh, Hossein
Mirakabadi, Abbas
Alizadeh, Hafezeh
Tematy:
anticoagulant factor
snake venom
Iranian Echis carinatus
chromatography
Pokaż więcej
Wydawca:
Polskie Towarzystwo Biochemiczne
Powiązania:
https://bibliotekanauki.pl/articles/1039597.pdf  Link otwiera się w nowym oknie
Opis:
Many snake venoms comprise different factors, which can either promote or inhibit the blood coagulation pathway. Coagulation disorders and hemorrhage belong to the most prominent features of bites of the many vipers. A number of these factors interact with components of the human blood coagulation. This study is focused on the effect of Echis carinatus snake venom on blood coagulation pathway. Anticoagulant factors were purified from the Iranian Echis carinatus venom by two steps: gel filtration (Sephadex G-75) and ion-exchange (DEAE-Sephadex) chromatography, in order to study the anticoagulant effect of crude venom and their fractions. The prothrombin time was estimated on human plasma for each fraction. Our results showed that protrombin time value was increase from 13.4 s to 170 s for F2C and to 280 s for F2D. Our study showed that these fractions of the venom delay the prothrombine time and thus can be considered as anticoagulant factors. They were shown to exhibit proteolytic activity. The molecular weights of these anticoagulants (F2C, F2D) were estimated by SDS/PAGE electrophoresis. F2C comprises two protein bands with molecular weights of 50 and 79 kDa and F2D a single band with a molecular weight of 42 kDa.
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Improved downstream process for the production of plasmid DNA for gene therapy
Autorzy:
Urthaler, Jochen
Buchinger, Wolfgang
Necina, Roman
Tematy:
plasmid DNA
production
gene- therapy
purification
alkaline lysis
chromatography
Pokaż więcej
Wydawca:
Polskie Towarzystwo Biochemiczne
Powiązania:
https://bibliotekanauki.pl/articles/1041381.pdf  Link otwiera się w nowym oknie
Opis:
Gene therapy and genetic vaccines promise to revolutionize the treatment of inherited and acquired diseases. Since viral vectors are generally associated with numerous disadvantages when applied to humans, the administration of naked DNA, or DNA packed into lipo- or polyplexes emerge as viable alternatives. To satisfy the increasing demand for pharmaceutical grade plasmids we developed a novel economic downstream process which overcomes the bottlenecks of common lab-scale techniques and meets all regulatory requirements. After cell lysis by an in-house developed gentle, automated continuous system the sequence of hydrophobic interaction, anion exchange and size exclusion chromatography guarantees the separation of impurities as well as undesired plasmid isoforms. After the consecutive chromatography steps, adjustment of concentration and final filtration are carried out. The final process was proven to be generally applicable and can be used from early clinical phases to market-supply. It is scaleable and free of animal-derived substances, detergents (except lysis) and organic solvents. The process delivers high-purity plasmid DNA of homogeneities up to 98% supercoiled form at a high yield in any desired final buffer.
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Chemical constituents of water hyacinth (Eichhornia crassipes) methanol leaf extract and its effect on selected enzymes of Periplaneta americana
Autorzy:
Adeleke, G.E.
Adedosu, O.T.
Ehigie, L.
Adegbola, P.I.
Olaniyi, A.A.
Agoola, T.O.
Ehigie, A.F.
Tematy:
Eichhornia crassipes
spectroscopy
chromatography
Periplaneta americana
antioxidant enzymes
esterases
Pokaż więcej
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Powiązania:
https://bibliotekanauki.pl/articles/2096284.pdf  Link otwiera się w nowym oknie
Opis:
Eichhornia crassipes (water hyacinth) possesses several biological properties. Periplaneta americana (cockroach) is a household insect pest that can disseminate pathogens. The present study analyses the chemical constituents of water hyacinth leaf methanol extract and its in vitro effects on antioxidant and esterase enzymes in cockroaches. Water hyacinth methanol extract (WHME) was subjected to gas chromatography-flame ionization detection (GC-FID). Crude enzyme preparations were obtained from nymph and adult cockroaches. In vitro effects of different concentrations (10–80 μg/ml) of WHME on superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST), acetylcholinesterase (AChE), and carboxylesterase (CE) in crude enzyme preparations were spectrophotometrically measured using cypermethrin (CYP) and chlorpyrifos (CPF) as reference insecticides. The GC-FID chromatogram of WHME showed the presence of gallic acid, para-hydroxybenzoic acid, eritosin, gentisic acid, catechin, protocatechuric acid, quercetin, and eugenol. The WHME and CPF reduced catalase in adults and SOD in nymphs, while CYP and CPF reduced SOD activity in the adults of P. americana. GST was significantly increased by WHME in both nymph and adult cockroaches. AChE was reduced by WHME, CYP, and CPF in nymphs, while CE was increased by WHME in nymphs and adults as compared to the control. In conclusion, our study indicates a high phenolic content in the water hyacinth leaf methanol extract, which increased the activities of the antioxidant enzymes AChE and CE in P. americana. The results also show that the efficacy and the mode by which the extracts could induce toxicity depend on the growth stage of the cockroach.
Dostawca treści:
Biblioteka Nauki
Artykuł

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