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51.
Radomir Konjevic Dragouub Grubii Mirjana Nekovi 《Photochemistry and photobiology》1987,45(S1):821-824
Abstract. The phototropic response of norflurazon-treated mung bean seedlings has been studied to evaluate the possible role of carotenoids, carotenoid-derived growth substances, or other factors in the perception/reaction system. Phototropism was slowed significantly in plants grown in white and blue light in the presence of norflurazon. This effect was evident in norflurazon-bleached seedlings, as well as in those whose pigment system was not affected, due to a shorter period of herbicide action. The possible modes of norflurazon action are discussed. 相似文献
52.
Ivan Damljanović Mirjana Vukićević Rastko D. Vukićević 《Monatshefte für Chemie / Chemical Monthly》2006,137(3):301-305
Summary. The conversion of alicyclic and aliphatic carbonyl compounds as well as aromatic aldehydes into the corresponding oximes (up
to quantitative yields) was achieved by simply grinding these reactants, hydroxylamine hydrochloride and sodium hydroxide
without solvent. However, this procedure was unsuccessful in the case of aromatic ketones. In this case it was necessary to
add silica gel as a catalyst. 相似文献
53.
K. Schaller R. Lenhardt V. Weber C. Euler 《Fresenius' Journal of Analytical Chemistry》1988,329(6):701-706
Summary It could be shown that the flow injection technique can be well introduced in labs which need a high sample throughput without any loss of precision. For normal labs with agrochemical tasks it is possible to adapt the proposed flow injection methods for nitrogen and phosphorus. For the determination of ammonia in juices and musts flow injection is better in precision and faster than the conventional methods. The determination of nitrate in plant extracts can be performed without any clean-up of the crude extract by introducing a dialysis cell in the normal flow injection system. For the determination of proline and arginine methods were developed for flow injection. Both are selective with a high precision and crude plant extracts can be injected for determination. Flow diagrams and equipment parameters are described. 相似文献
54.
Critical micelle concentrations (CMC) of sodium salts of cholic, deoxycholic and chenodeoxycholic acids in phosphate buffer (pH 7.92) have been determined from microcalorimetric titration curves. The obtained values of 18.4±0.6, 5.3±0.2 and 7.0±0.2 mM, respectively, for Na cholate, Na deoxycholate and Na chenodeoxycholate are close to literature values obtained by other methods. CMC values for secondary micelles were also obtained. This microcalorimetric titration method gives highly reproducible results and rapid determination of CMC values of bile acid salts. 相似文献
55.
Summary The semiquantitative determination of the amino acids glycine,dl-alanine,-alanine,l-asparagine,dl-aspartic acid andl-glutamic acid, using theWeisz ring oven, is described. The determination is carried out by forming a spot of cupric hydroxide in the centre of a round filter paper. The spot is then partly dissolved by covering it with several drops of the solution of the amino acid to be determined. The green-blue complex formed is washed on the ring oven with water into rings, and the intensity of the rings is compared with a standard scale, prepared from solutions of known concentration of the appropriate amino acid.
Zusammenfassung Die halbquantitative Bestimmung der Aminosäuren Glycin,dl-Alanin,-Alanin,l-Asparagin,dl-Asparaginsäure undl-Glutaminsäure nach der Ringofenmethode vonWeisz wird beschrieben.Die Bestimmung wird so ausgeführt, daß zuerst in der Mitte eines Rundfilters ein Fleck von Kupfer(II)-hydroxyd ausgefällt wird. Dieser wird dann zum Teil durch das Aufbringen der zu bestimmenden Aminosäurelösung gelöst.Die entstandene grün-bläuliche, wasserlösliche Komplexverbindung wird auf dem Ringofen mit Wasser in die Ringzone gewaschen und mit Standardringen verglichen, die in gleicher Weise aus Lösungen mit bekanntem Gehalt an betreffender Aminosäure hergestellt wurden.
Résumé On décrit le dosage semiquantitatif d'acides aminés: le glycocolle, ladl-alanine, la-alanine, lal-asparagine, l'acide aspartiquedl et l'acide glutamiquel, au moyen du four annulaire deWeisz. On réalise le dosage en formant une tache d'hydroxyde cuivrique au centre d'un papier filtre rond. On dissout alors partiellement la tache en la recouvrant de plusieurs gouttes de la solution de l'acide aminé à doser. On lave sur le four annulaire le complexe bleu-vert formé, avec de l'eau sur les anneaux, et l'on compare l'intensité des anneaux à une échelle d'étalons, préparée à partir de solutions de concentration connue de l'acide aminé approprié.相似文献
56.
Tomislav J. Janjić Lidija B. Pfendt Mirjana B. Pasulj 《Monatshefte für Chemie / Chemical Monthly》1984,115(2):125-133
Heterogeneous equilibria in saturated solutions of sparingly soluble diprotic acids: 1,2-, 1,3- and 1,4-benzenedicarboxylic acid, and octanedioic acid, respectively, at ionic strengthI=1 (NaCl) and the temperature of 25 °C, have been investigated. The corresponding equilibrium constants were determined by the application of three independent methods: the formation function method, the method of protons bound to the acid in the solution and the solubility method. The results obtained by these three different methods are in good agreement.
Untersuchung heterogener Gleichgewichte in gesättigten Lösungen schwerlöslicher diprotischer Säuren
Zusammenfassung Es wurden die heterogene Gleichgewichte in gesättigten Lösungen schwerlöslicher diprotischer Säuren (Benzol-1,2-, -1,3- und-1,4-dicarbonsäuren und Oktandisäure) bei einer IonenstärkeI=1 (NaCl) und der Temperatur von 25 °C untersucht. Die entsprechende Gleichgewichtskonstanten wurden mit drei unabhängigen Methoden bestimmt: mit der Methode der Bildungsfunktion, der Methode der an die Säure in Lösung gebundenen Protonen, bzw. mit der Methode der Löslichkeitsbestimmung. Die erhaltenen Ergebnisse stehen in guter Übereinstimmung.相似文献
57.
A new route towards enantiopure hydroxylactones 3 and ent-3, the final chiral precursors in an enantiodivergent synthesis of (+)- and (−)-muricatacin, has been developed starting from d-xylose. 相似文献
58.
59.
Mirjana Stojanovic 《Central European Journal of Physics》2013,11(10):1337-1349
We give an existence-uniqueness result for linear and nonlinear time fractional evolution equations with singularities in corresponding norm in extended Colombeau algebra of generalized functions using fractional analog for Duhamel principle. Paper deals with some nonlinear models with singularities appearing in viscoelasticity and in anomalous processes which have met great interest among researchers who consider them as a challenge in recent years. 相似文献
60.
Thomas Luxbacher Mirjana Čurlin Irena Petrinić Hermina Bukšek Tanja Pušić 《Cellulose (London, England)》2014,21(5):3829-3839
Raw cotton knitted fabrics of Greek, Indonesian, and Indian origin were investigated through surface characterization before and after processing. Surface modifications of all the knitted cotton fabrics were objectively evaluated through zeta potential measurements within a range of the electrolyte solution pHs, and swelling over time. Streaming potential coefficients of different cotton knitted fabrics were applied in order to establish a correlation between the properties of the raw and treated cotton knitted fabrics of different origins. The rate of swelling was calculated from the streaming potential coefficients of the raw knitted fabrics before and after different treatments. Swelling rate for different origins and different treatments of cotton knitted fabrics and the correlation coefficients were obtained using linear regression. Additionally, a data cluster analysis was performed in order to group different origins of cotton, while all the treatments were sorted according to zeta potential and the rate of swelling coefficients. The obtained results showed differences among the clusters, depending on the origin of the cotton knitted fabrics and treatments they were exposed to. 相似文献