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1.
Zusammenfassung Die biologische Wirksamkeit der Gibberelline A1 bis A10, A13 und A14 wurde bei der Einsetzung von Parthenokarpie inMalus sylvestris Mill. festgestellt. Die Gibberelline A4 und A7 waren sehr wirksam, A1, A2, A3, A9, A10, A13 und A14 waren von mittelmässiger Wirksamkeit, während A5, A6 und A8 waren unwirksam. Die mehr wirksamen Gibberelline besitzen, vom molekularen Standpunkt betrachtet, in der Stellung 7 keine OH-Gruppe.

On leave from Osaka Prefecture University, Osaka, Japan.  相似文献   

2.
Zusammenfassung Es wird eine neue Methode vorgeschlagen, Acetaldehyd, Propionaldehyd und Butyraldehyd in Gegenwart von CH4, C2H6, C3H8, C2H4, C3H6, C2H2, CO2, CO, N2, H2 und O2 quantitativ zu bestimmen. Die Methode besteht darin, das Gasgemenge mit Hilfe eines Orsatschen Apparates durch eine bei 20°C gesättigte, Chromtrioxyd und Schwefelsäure enthaltende Natriumsulfatlösung zu schicken, welche die oben genannten Aldehyde selektiv absorbiert.  相似文献   

3.
Summary The space-group of Cu(NH3)4SO4·H2O isD 2h 16 orD 2h 13 (D 2h 5 , D 2h 1 ) with a=7,07, b=12,12, c=10,66 Å ± 1%.  相似文献   

4.
    
Summary Pharmacosiderite has been investigated by Laue, powder, and rotation photographs. The space group isT d 1 . From the analysis of the literature the formula [Fe4(OH)4(AsO4)3] · K · 6–7 H2O has been derived. K+ and H2O fill up the large channels of a framework of AsO4-tetrahedrons and Fe3(OH)3O3-octahedrons. The intensities calculated are generally in conformity with the observation.  相似文献   

5.
Summary The Noetherian surfaceF 4 (3) , which is represented on a plane by a linear 3 system ofC 9(A 1 3 A 2 3 A 3 3 A 4 3 A 5 3 A 6 3 A 7 3 A 8 3 A 9 2 A 10), possesses generally only one linear pencil of elliptic cubics. IfA i (i=1, 2, , 9) are the basis points of aHalphen pencil ofC 9,A 10 is infinitely near toA 9, and in this caseF 4 (3) is a not trivial example of such a surface with two pencils of elliptic cubics.  相似文献   

6.
Zusammenfassung Antibiotikum U-22324 ist ein zyklisches Peptid, das aus Kulturflüssigkeit vonTrichoderma viride isoliert wurde. Das Peptid hat die Aminosäurenzusammensetzung (GluN)2(Glu)1(Pro)2(Gly)1(Ala)2(Dimethyl ala)8(Val)2(Leu)1.  相似文献   

7.
Antibodies cross-reactive with 4 major aflatoxins were demonstrated three weeks after immunization of rabbits with an immunogen which was prepared by conjugating aflatoxin B3 to bovine serum albumin. Aflatoxin B3 was first converted to its hemisuccinate before conjugation to the protein. Tritiated aflatoxin B1 (AFB1) was used as the marker ligand both for antibody titer determination as well as for analysis of antibody specificity. Competitive RIA revealed that the antibodies have good cross-reactivity with aflatoxins B1, B2, G1, and G2 when tritiated AFB1 was used as the marker ligand. The concentrations causing 50% inhibition of binding of3H-AFB1 to the antibodies by unlabeled aflatoxins B1, B2, G1, G2 and B3 were found to be 0.25, 3.34, 0.32, 4.0 and 0.53 ng/assay, respectively. The antibodies could be used for simultaneous analysis of aflatoxins B1 and G1, two of the most important toxic metabolites produced byAspergillus flavus andA. parasiticus.  相似文献   

8.
Summary Thin-layer chromatography on silica gel is described as a new method for the separation and identification of the gibberellins A1, A3, A4, A5, A7, A8, and A9.  相似文献   

9.
Summary The catalytic mutation of the ions Al3+ and MoO 4 2– on the mixed carrier Cd(OH)2/Co(OH)2(Tr) is recognizable by the fact that the combination Tr+Al3++MoO 4 2– is more active in the decomposition of H2O2 than the combination Tr+MoO 4 2– +Al3+.  相似文献   

10.
Summary The viscosity, apparent molar volume and conductivity of KBrO3, NaBrO3, KIO3, NaIO3, K2SO4 and Na2SO4 at mass fraction of dioxane (10, 20 and 30%) — water mixtures at 30–45°C±0.01°C have been measured. The ions appear to interact and the ion-solvent interaction is of the order BrO 3 >IO 3 >SO 4 2– .  相似文献   

11.
A forecasting model for yt based on its relationship to exogenous variables (e.g. x?t) must use x?t, the forecast of x?t. An example is given where commercially available x?t's are sufficiently inaccurate that a univariate model for yt appears preferable. For a variety of types of models inclusion of an exogenous variable x?t is shown to worsen the yt forecasts whenever x?t must itself be forecast by x?t and MSE (x?t) > Var (x?t). Tests with forecasts from a variety of sources indicate that, with a few notable exceptions, MSE (x?t) > Var (x?t) is common for macroeconomic forecasts more than a quarter or two ahead. Thus, either:
  • (a) available medium range forecasts for many macroeconomic variables (e.g. the GNP growth rate) are not an improvement over the sample mean (so that such variables are not useful explanatory variables in forecasting models), and/or
  • (b) the suboptimization involved in directly replacing x?t by x?t is a luxury that we cannot afford.
  相似文献   

12.
Zusammenfassung Die Infrarotspektren der Einschlussverbindungen [Ni(CN)2(NH3)(C6H6)] und [Ni(CN)2(NH3)C4H5N] wurden untersucht und mit den Spektren von gasförmigen und flüssigen C6H6 bzw. C4H6N verglichen.

Clathrate work was carried out under a research grant by University of Western Australia. Nickel cyanide-ammonia clathrates were further investigated by the author at the Punjab University (Chandigarh, India), University of Rome (Rome, Italy) and Fisk University (Nashville, Tennessee, USA).  相似文献   

13.
Zusammenfassung Es wurde die Reaktion zwischen Th4+ und WO4 2–-Ionen durch amperometrische, pH und konduktometrische Titrationen zwischen Th(NO3)4 und Na2WO4 untersucht. Elektrometrisch konnte bewiesen werden, dass sich zwischen pH 4.50–5.75 normales Thoriumtungstat ThO2 · 2WO3 bildet.  相似文献   

14.
Summary Previous reports suggested that the major cytosolic aldehyde dehydrogenase (ALDH1) was present in fetal and infant livers, but the major mitochondrial isozyme (ALDH2) was absent or severely diminished. Re-examination by means of starch gel electrophoresis followed by enzyme activity staining, and by means of dot blot immuno-hybridization of liver samples with known genotypes of theALDH 2 locus, indicated that bothALDH 1 andALDH 2 genes are expressed in fetal and infant livers. In addition, ALDH4 isozyme was also observed. The results imply that a fetus with the usual homozygousALDH 2 1 /ALDH 2 1 genotype, but not one with the atypicalALDH 2 1 /ALDH 2 2 orALDH 2 2 /ALDH 2 2 , is capable of detoxifying acetaldehyde transferred from the mother.  相似文献   

15.
    
Summary Eglestonite has been investigated by powder and rotation photographs;a=8,02±0,02 Å,Z=3; the space-group is O h 9 . The Hg-atoms form Hg2-groups as in Hg2Cl2, and therefore the formula must be written Hg4Cl2O. It was not yet possible to find the positions of Cl and O, because their scattering-power is too low.  相似文献   

16.
In this paper we show that optimal trading results can be achieved if we can forecast a key summary statistic of future prices. Consider the following optimization problem. Let the return ri (over time i=1, 2, ..., n) for the ith day be given and the investor has to make investment decision di on the ith day with di=1 representing a ‘long' position and di=0 a ‘neutral' position. The investment return is given by rni=1ridicΣn+1i=1didi−1∣, where c is the transaction cost. The mathematical programming problem of choosing d1, ..., dn to maximize r under a given transaction cost c is shown to have an analytic solution, which is a function of a key summary statistic called the largest change before reversal. The largest change before reversal is recommended to be used as an output in a neural network for the generation of trading signals. When neural network forecasting is applied to a dataset of Hang Seng Index Futures Contract traded in Hong Kong, it is shown that forecasting the largest change before reversal outperforms the k‐step‐ahead forecast in achieving higher trading profits. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   

17.
Riassunto Sono misurate le velocità di reazione della lisozima con 0.05M ditiotreitolo, HSCH2CH2OH, (HSCH2CH2COO) e H2SCH2CH2NH2 in tampone borace di pH 10 e in alcune altre concentrazioni e pH. La cinetica della reazione col ditiotreitolo è differente da quella con HSCH2CH2OH e viene data una interpretazione di questo fenomeno.

This work was aided by a grant and a Career Development Award (to G.G.) from the National Institutes of Health, U.S. Public Health Service.  相似文献   

18.
Consider forecasting the economic variable Yt+h with predictors X t, where h is the forecast horizon. This paper introduces a semiparametric method that generates forecast intervals of Yt+h| X t from point forecast models. First, the point forecast model is estimated, thereby taking advantage of its predictive power. Then, nonparametric estimation of the conditional distribution function (CDF) of the forecast error conditional on X t builds the rest of the forecast distribution around the point forecast, from which symmetric and minimum‐length forecast intervals for Yt+h| X t can be constructed. Under mild regularity conditions, asymptotic analysis shows that (1) regardless of the quality of the point forecast model (i.e., it may be misspecified), forecast quantiles are consistent and asymptotically normal; (2) minimum length forecast intervals are consistent. Proposals for bandwidth selection and dimension reduction are made. Three sets of simulations show that for reasonable point forecast models the method has significant advantages over two existing approaches to interval forecasting: one that requires the point forecast model to be correctly specified, and one that is based on fully nonparametric CDF estimate of Yt+h| X t. An application to exchange rate forecasting is presented. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

19.
Zusammenfassung In Thiosulfatlösungen von mäßiger Stärke bildet Silber die zwei Ionen Ag(S2O3) 2 3– und Ag(S2O3) 3 5– , deren Komplexkonstanten bestimmt wurden.  相似文献   

20.
Zusammenfassung Untersuchungen derr II-Region desT 2-Bakteriophagen. Es wurde eine genetische Analyse derr II-Region desT 2-Bakteriophagen durchgeführt zur Feststellung, ob die Befunde, die sich auf die Funktionsteile innerhalb derr II-Region desT 4-Phagen beziehen, in bezug auf dier II-Region desT 2-Phagen verallgemeinert werden können. Die Mutanten wurden mit Hilfe von 5-Bromouracil und Akridineorange isoliert und dieh + r-Mutanten nach demselben Schema wie fürT 4-Phagen weiter differenziert. Sechzig ausgewählte Mutanten wurden nach funktionaler Identität geprüft, was zur Feststellung führte, dass die gesamte Region als eine Einheit funktioniert.  相似文献   

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