Search results for "Chlorin"
showing 10 items of 374 documents
Design of enzyme-mediated controlled release systems based on silica mesoporous supports capped with ester-glycol groups
2012
[EN] An ethylene glycol-capped hybrid material for the controlled release of molecules in the presence of esterase enzyme has been prepared. The final organic-inorganic hybrid solid S1 was synthesized by a two-step procedure. In the first step, the pores of an inorganic MCM-41 support (in the form of nanoparticles) were loaded with [Ru(bipy) 3]Cl 2 complex, and then, in the second step, the pore outlets were functionalized with ester glycol moieties that acted as molecular caps. In the absence of an enzyme, release of the complex from aqueous suspensions of S1 at pH 8.0 is inhibited due to the steric hindrance imposed by the bulky ester glycol moieties. Upon addition of esterase enzyme, del…
Comparison of the effects of chloral hydrate and trichlorethanol on the EEG of the isolated perfused rat brain.
1973
An isolated perfused rat brain preparation was used to compare the effects of chloral hydrate and its metabolite trichloroethanol on the EEG. The concentrations of chloral hydrate and trichloroethanol in the perfusion medium ranged from 1.5 to 5.5 mM. 5, 10, 15, and 30 min after the beginning of the perfusions EEG-recordings were taken. The recordings were evaluated both by a descriptive method and by a simple quantitative appraoch, counting the waves with an amplitude greater than 50 microvolts and averaging this value for a period of 1 sec. The following results were obtained: Both drugs exhibited CNS depressant activity. Between 5 and 10 min of perfusion the effect of trichloroethanol wa…
Albumin binding and hydrophobic character of promazine and chlorpromazine metabolites.
1972
1. The binding of didesmethylpromazine, promazine N-oxide, 2-hydroxypromazine, promazine sulfoxide, monodesmethylpromazine sulfoxide, didesmethylchlorpromazine, chlorpromazine N-oxide, and chlorpromazine sulfoxide to bovine serum albumin was determined by means of sephadex gel filtration. 2. The albumin binding of these substances was characterized by the following parameters: the percentage α of free substance, the percentage β of bound substance, the binding constants K1, k+ and m, the number of binding sites per albumin molecule, and the free binding energy ΔFo. 3. The partition coefficients between n-octanol and buffer solution, pH 7.40, were measured for the above mentioned metabolites…
13C NMR study on the methoxy carbon chemical shifts in chloro-substituted anisoles and guaiacols
1983
The 13C NMR chemical shifts of methoxy carbons in chlorinated anisoles and guaiacols have been measured for acetone-d6 solutions. Multiple linear regression analysis, and also ‘simple sum rule’ calculations, have been used to estimate the effects of the chlorine atoms (the position and degree of substitution) on the chemical shifts. The most important effects have shown to be due to the chlorine atoms adjacent to the methoxy and hydroxy substituents. For chlorinated guaiacols, the greatest effect is due to the chlorine atom adjacent to the methoxy group. For chlorinated anisoles, the substituents adjacent to the methoxy group (2,6-disubstitution) cause large effects. For both groups of comp…
Mercury and chlorinated hydrocarbons in zoobenthos of Lake Päijänne, Finland
1979
The average amounts of mercury, PCBs, and sigma DDT (primarily DDE), found in macrozoobenthos, on the wet basis, in Lake Päijänne, Finland, for the time period 1972-1974, were 79 ng/g, 29 ng/g, and 8 ng/g, respectively. Lindane was found in negligible amounts in only 2% of the samples examined; aldrin was present in 10% of the samples; no dieldrin was detected. Mercury and PCB concentrations varied regionally in the lake. PCB and sigma DDT concentrations were greater in the predatory bottom animals than in the herbivores or detritus feeders, and the amounts of chlorinated hydrocarbons were greater in profundal animals than in littoral animals. No significant correlation was apparent between…
Transportation of complexing agents released by pulp and paper industry: A Finnish lake case
1996
Complexing agents (EDTA, DTPA) are used to bind metal ions in pulp and paper industry. Their role will increase significantly when the total chlorine free (TCF) processes will be applied to a larger extent. EDTA and DTPA were analysed in the waters from the southern part of the Lake Saimaa (SE Finland) influenced by the effluents of three pulp and paper mills. The samples were collected at different distances from the points of emission. The results of analyses suggest that EDTA can persist in lake water and is able to propagate for considerable distances, while DTPA can be detected only in the near surroundings of the site of release. Some EDTA was found even in the sampling points that we…
Some fundamentals of the vapor and solution growth of ZnSe and ZnO
1999
Abstract Some fundamentals of ZnSe and ZnO vapor and solution growth are investigated. Residual water present in gases or gaseous mixtures such as H 2 , Ar or H 2 +H 2 O is shown to act as a sublimation activator in the vapor-phase transport of both compounds. The processes involved in the growth by chemically activated sublimation with such gases and gas mixtures have been studied by close-spaced vapor transport (CSVT). The ZnSe growth rate is found to be constant, while in the ZnO case a high initial growth rate is followed by slower growth subsequently. Using a theoretical model, the thermodynamic constants of the transport – energies of activation, sublimation and condensation and entha…
Extending Limits of Chlorine Kinetic Isotope Effects
2012
Chlorine kinetic isotope effects exceeding semiclassical limits were observed in enzyme-catalyzed reactions, but their source has not been yet identified. Herein we show that unusually large chlorine kinetic isotope effects are associated with reactions in which chlorine is the central atom that is being passed between two heavy atoms. The origin of these large values is the ratio of imaginary frequencies for light-to-heavy species (the so-called temperature-independent factor).
Chloracne after release of TCDD at Seveso, Italy
1981
ABSTRACT The paper deals with clinical and epidemiological findings concerning persons showing skin lesions after release of TCDD at Seveso. A positive association was observed between geographical distribution of cases and levels of soil contamination. Gastro-intestinal tract impairments were more frequently observed in children with chloracne than in children from the same areas showing no skin lesions. To date, no major immunological involvement has been observed in samples of children exposed to TCDD.
EVALUATION OF AEROBIC AND ANAEROBIC BACTERIAL DECHLORINATION POTENTIAL OF A 1,2-DICHLOROETHANE CONTAMINATED AQUIFER
2023
Chlorinated solvents, belonging to the class of chlorinated aliphatic hydrocarbons (CAHs), are synthetic organohalide chemicals frequently found as contaminants of groundwater and soil, due to their widespread use in several industrial processes and improper disposal methods. These compounds pose serious health threats because of their toxic and sometimes carcinogenic effects. Among these compounds, 1,2-dichloroethane (1,2-DCA) is one of the most common aquifer contaminants, considered toxic and classified as a possible human carcinogen. Remediation approaches toward these contaminants include conventional cleanup technologies based on physical/chemical methods, and bioremediation, consider…