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991.
Abstract

On behalf of the Umweltbundesamt the Fraunhofer Gesellschaft has developed a software system (SAR-system) comprising more than 90 estimation models for endpoints relevant in environmental risk assessment. These estimation models are based on the approach of quantitative structure-activity relationships (QSAR). All models were checked for their validity and application range. In the last months the Umweltbundesamt started to test the applicability of some models concerning the endpoints fish acute toxicity, daphnia acute toxicity and ready (i.e., ultimate) biodegradability in the daily routine of the notification procedure. For testing these models the corresponding confidential data given in the dossiers of substances notified 1993 in Germany, were used. We were able to make calculations for 36% of the notified substances. For the remaining 64% of the chemicals it was impossible to accomplish SAR estimations due to several reasons, e.g., ionic structure of the compounds. Different results for the applicability of the mentioned endpoints are obtained. The predictions of the fish and Daphnia toxicity are in sufficient agreement with the experimental results, in case of the fish toxicity we receive 58% agreement, for the Daphnia toxicity 56% The corresponding values which were obtained in the US EPA/E.C. Joint Project on the evaluation of (quantitative) structure activity relationships were 82.3% and 70.9% About 300 different models were used for the calculations of these endpoints within the framework of the EPA/EC project. The SAR-system presented here contains 8 models for estimating the fish toxicity and 6 models for the Daphnia toxicity. For the prediction of the biodegradability the results obtained with the SAR-system are rather poor and have to be improved. Meanwhile the SAR-system is commercially available and can be ordered at the Fraunhofer Institute for Environmental Chemistry and Ecotoxicology, Schmallenberg (Germany).  相似文献   
992.
JETP Letters - The temperature dependences of attenuation and the velocity of ultrasonic waves at frequencies of 26–158 MHz in a CaF2 fluorite crystal at the substitution of...  相似文献   
993.
JETP Letters - The vibrational properties of yttrium iron garnet Y3Fe5O12 at a high quasihydrostatic pressure are studied by the Raman spectroscopy method. Raman spectra are measured in a...  相似文献   
994.
JETP Letters - Low-temperature (5 K) microphotoluminescence has been measured in order to study individual luminescent centers formed by the cores of partial dislocations in a CdTe/Si film and a...  相似文献   
995.
Gusakov  E. Z.  Popov  A. Yu. 《JETP Letters》2021,114(3):138-142
JETP Letters - The possibility of the localization of longitudinal waves in the intermediate frequency range in the edge transport barrier of a toroidal nuclear fusion facility is discovered. It is...  相似文献   
996.
Volkov  M. K.  Pivovarov  A. A. 《JETP Letters》2021,114(6):309-313
JETP Letters - The partial width of the $$\tau \to {{K}^{ - }}{{K}^{0}}{{\nu }_{\tau }}$$ decay has been calculated within the extended Nambu–Jona-Lasinio model including the contact and...  相似文献   
997.
Udintseva  M. S.  Efremov  A. V.  Smirnov  D.  Makarova  A.  Naumov  S. V.  Shamin  S. N.  Galakhov  V. R. 《JETP Letters》2021,114(8):475-478
JETP Letters - The oxygen K-edge X-ray absorption spectra in EuBaCo2O5.52 ± 0.02 and EuBaCo2O5.24 ± 0.02 cobaltites are measured at temperatures of 300 and 440 K, which are below and...  相似文献   
998.
Niyazov  R. A.  Aristov  D. N.  Kachorovskii  V. Yu. 《JETP Letters》2021,113(11):689-700
JETP Letters - We review recent studies of the spin-dependent tunneling transport via an Aharonov–Bohm interferometer (ABI) formed by helical edge states. We focus on the experimentally...  相似文献   
999.
Zubarev  N. M.  Mesyats  G. A. 《JETP Letters》2021,113(4):259-264
JETP Letters - A mechanism for the initiation of explosive electron emission at the interface between the cathode and a dense gas is proposed. It is based on the accumulation of positive ions,...  相似文献   
1000.
Yakushkin  E. D.  Sandler  V. A. 《JETP Letters》2021,113(5):352-355
JETP Letters - A magnetically induced deceleration of the initial stage of the isothermal phase transition of ferroelastic-superprotonic cesium hydrogen sulfate has been detected. The effect is...  相似文献   
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