Search

The use of an image furnace made possible the construction of an X ray device capable of studying samples up to 3,200°C in air or controlled atmosphere. The apparatus is a high temperature diffractometer of the Bragg-Brentano type. The goniometer has an horizontal axis; X ray tube and counter are symetrical1y rotated about the sample. Resume Un ensemble permettant d'effectuer des experiences de diffraction des rayons X jusqu'a 3 200°C, a l'air ou sous atmosphere controlee a ete construit. un comprend un four a image auquel est associe un diffractometre de type Bragg – Brentano dont le goniometre est a axe horizontal Le tube de rayons X et le compteur se depiacent symetriquement aut our de l'echantilon.

Zeise's salt, anhydrous and monohydrate, has been prepared by a new method similar to the original method used by Zeise. The infrared and laser Raman spectra of the anhydrous Zeise's salt together with the infrared spectra of the deutero and bromo analogs, are reported and discussed. The vibrational spectra are interpreted in terms of a cyclopropane-like ring structure, obtained by the insertion of the platinum atom into the double bond.

A method is given for stability analysis of a rapidly adapting model-reference system. The instantaneous value of the difference between model output and system output is used to adjust system gain. With proper compensating circuits in the adaptive controller, an error in plant gain is corrected in a time interval which is much less than the rise time of the system. The system performs equally well with square-wave, triangular, or sinusoidal inputs.

Quantitative data for the rate of decomposition of β-indolyl acetic acid added to soils have been obtained and the rate of decomposition shown to be very rapid. Normal dressings of organic manures such as dung and dried blood have been found to increase the auxin content of soils towards the maximum value in what has been previously described as the “normal auxin range” of soils. This increase may be maintained for a period of some months, and in the dried blood type of manures additional auxins arc produced as a result of their decomposition in the soil. It has been shown that β-indolyl acetic acid is one of the auxins thus produced. Heavy dressings of organic manures may produce a considerable increase in auxin content of the soil but this increase is rapidly followed by a reduction to a value within the normal range. Moreover specially washed soils with a low auxin content show an increase in auxin content on ageing to a value within the normal range. These facts suggest the existence of a mechanism within the soil to control the soil auxin content within certain limits or suggest what is tentatively described as an “auxin balance” in the soil.

Aus HMO-Berechnungen des s-Triazolo[3.4-a]isochinolins (1) geht u. a. ein hoher Doppelbindungscharakter der C-5/C-6-Bindung hervor, was auch experimentell bei Halogenaddition, katalytischer Hydrierung und Permanganat-Oxydation beobachtet wird. Oxydationsreaktionen der Derivate von 1 zeigen, das ungesattigte Seitenketten unter gleichen Bedingungen gleichzeitig oxydativ abgebaut werden. Condensed Isoquinolines, III. Studies on the Reactivity of s-Triazolo[3.4-a]isoquinolines HMO-Calculations of s-triazolo[3.4-a]isoquinoline (1) reveal a high doublebond character of the C-5/C-6 bond. Halogenaddition, catalytic hydrogenation and oxidation reactions are in experimental agreement. It appears from oxidation reactions of derivatives of 1 that unsaturated side chains are also oxidatively degradated at the same time under the same conditions.

Penta-p-tolylantimony crystals are monoclinic, space group P21/c, with a = 14.545(5), b = 4(6), c = 19.754(8) Å, β = 122.88(4)°, and Z = 4. The structure was solved by the standard heavy-atom method and anisotropic refinement on 1677 independent observed reflections led to a conventional R factor of 0.051. Unlike pentaphenylantimony, which is known to exist as square pyramidal molecules in the crystal, the corresponding penta-p-tolyl derivative exhibits the more common trigonal bipyramid structure. The Sb—C equatorial bond length average, 2.16 Å, is significantly shorter than the axial average, 2.26 Å. Two of the C—Sb—C bond angles in the equatorial plane (113, 130°) differ considerably from 120°, but the other angles around antimony are normal. Packing forces appear to play a determining role in the structures observed for penta-aryl derivatives of antimony in the solid state.

The light-induced isomerisation of allylic ethers in the presence of pentacarbonyliron has been compared with that brought about by a basic heterogeneous catalyst, KNH2–Al2O3. The reaction on the basic catalyst proceeds through the usual cis-mechanism. In contrast, the carbonyliron reaction gives cis- and trans-isomers, in a 1 : 1 ratio in the case of allyl phenyl ether. A π-complex was detected (by n.m.r. spectroscopy) as an intermediate in the reaction. The formation of a catalyst which was particularly active for the thermal isomerisation of olefinic double bonds was detected during the irradiation of pentacarbonyliron in allyl phenyl ether. 3-Propoxycyclohexene was readily isomerised under these conditions, whereas it remained unchanged in the presence of very strong bases. Conformational effects of the ring were observed.

The spatial framework for which the Census of Canada provides data has evolved, through successive censuses, to meet the need of users. Because of the changing nature of the electoral districts of the early censuses, a more permanent spatial framework, namely, the county, and an equivalent area called the census division, was introduced in the 1921 and 1931 censuses. After World War II, users of census data requested a smaller spatial framework. In. 1951 data were available at the municipality level and, in 1961, all census data taken on a 100 per cent basis were available at the enumeration area level. Currently, the ability to provide census data for user-specified areas is being developed through a geocoding system.

Photolyse und Thermolyse verschiedener Heterocytclen, substituiert mit einer Benzotriazolyl-(1)-Gruppe in Nachbarstellung zum Ringstickstoff (3a–k,4a–c), wurden untersucht. Die Photolyse lieferte im Falle der Benzimidazol-Derivate Benzimidazo [1.2-a]benzimidazole (5), in allen anderen Fallen verlief sie undefiniert. Bei der Thermolyse in Polyphophorsaure entstanden nur in 4 Fallen definierte Produkte, und zwar die kondensierten Benzimidazole 7–10. Die Funktion der Phosphorsaure bei diesen Pyrolysen wurde untersucht. Thermolysis and Photolysis of 1-Benzotriazolyl Derivatives The photolysis and thermolysis of different heterocycles containing a 1-benzotriazolyl substituent adjacent to their ring nitrogens (3a–k, 4a–c), have been studied. The photolysis of benzimidazole derivatives gave benzimidazo[1,2-a]benzimidazoles (5). In all other cases undefined decomposition products were obtained. Thermolysis in polyphosphoric acid afforded well-defined products only in 4 cases; these were also condensed benzimidazoles (7–10). The function of phosphoric acid in these pyrolyses has been studied.

Heterocyclen mit Chlor in Nachbarstellung zum Ringstickstoff reagieren bei 60–160° mit ν-Triazol zu den entsprechenden ν-Triazolyl-(1)-Derivaten (3) oder weiter unter Stickstoffabspaltung zum kondensierten Imidazo-Heterocyclus. Von den ν-Triazolyl-(1)-Derivaten konnte nur das Pyrimidin-Derivat 3c durch Thermolyse in Polyphosphorsaure in das entsprechende Imidazo-pyrimidin 4 ubergefuhrt werden. Die ubrigen erleiden andersartige, zu undefinierten Produkten fuhrende Zersetzung. Thermolysis of ν-Triazolyl Derivatives Reaction of heterocycles bearing a chlorine adjacent to a ring nitrogen atom with ν-tiazole at 60–160° results in the formation of 1-ν-triazolyl-derivatives (3) or in subsequent elimination of nitrogen and formation of condensed imidazo heterocycles. Of the l-ν-triazolyl-derivatives only the pyrimidine derivative 3c can be transformed into the corresponding imidazo pyrimidine 4. The others undergo another kind of decomposition, which leads to undefined products.

The substitution reaction of bipyridyl with potassium trichloro (2,5-dimethyl 3-hexyne 2,5-diol) platinate(II) has been studied in 90% methanol -10 water mixtures at various temperatures. The reaction proceeds in several steps of which two have been well defined. Two rate constants were measured at 25°C: k 1obs = 25 × 10 −3 sec −1 k 2obs = 0.2 × 10 −3 sec −1 The first constant depends on the bipyridyl concentration and the second is independant of bipyridyl concentration. The rate constant found compared with those of Zeise's salt suggest a greater trans effect for the acetylenic glycol, as compared to the ethylene

Because of the progressively greater distances from sources of hydroelectric power to large load centers, there is a constant search for more efficient and less costly means of long-distance transmission. This paper proposes a half-wavelength transmission system for point-to-point transmission of power to eliminate many of the operational and design problems associated with conventional long transmission lines.

Introducing the Self-Adjusting Accelerator, a completely new digital computer method of solving a power system network load-flow is presented. With no sacrifice in accuracy, a mathematically rigorous solution (employing A B C D1 constants) is obtained using less computer time than any other nodal iterative method.

Bei Metathese-Reaktionen mit dem System (I) erhalt man je nach der Konzentration der Katalysatoren unterschiedliche Anteile an Metathese- und an Alkylierungsreaktionen, indem unterhalb eines Olefin-Katalysator-Verhaltnisses von 70 nur Alkylierung, oberhalb von 400 nur Metathese und dazwischen die beiden Reaktionen erfolgen.

Guilhon Jean, Caillier R., Hubert J. Action d’un nouveau dérivé de l’imidazole sur les nématodes parasites du tube digestif du mouton. In: Bulletin de l'Académie Vétérinaire de France tome 125 n°9, 1972. pp. 445-452.

Die Kettenabbruchreaktion bei der Polymerisation von dem LEUCHSanhydrid des γ-Benzyl-L-glutamates wurde an Modellsubstanzen untersucht. Die Diester der Glutaminsaure sind in Dioxanlosung stabil, zerfallen aber in Anwesenheit von Kohlendioxyd und ergeben dabei Pyroglutaminsaureester. Diese Reaktion stellt die intramolekulare Aminolyse eines Esters dar. Das Studium der Reaktionskitnetik in Ab- und Anwesenheit von Aminen ergab, das der Katalysator des Systems eine undissoziierte Carbaminsaure ist, gebildet aus dem Amino-diester und CO2. Die Katalyse lauft ab nach einem „Zwei-Centrenpush-pull”-Mechanismus. Der vorgeschlagene Reaktionsmechanismus erklart, weshalb der CO2-Druck mit erster Ordnung, das Substrat mit zweiter Ordnung in das Reaktionsgeschehen eingehen. Die an Hand von Modellen erhaltenen Ergebnisse werden auf die Polymerisation von LEUCHSanhydriden von Glutamaten angewendet. Die Abbruchreaktion ist ziemlich ungewohnlich, weil sie als bimolekulare Reaktion nur bei einer der beiden Ketten zum Kettenabbruch fuhrt. The chain termination reaction in the polymerization of the LEUCHS-anhydride of γ-benzyl-L-glutamate has been investigated on model substances. Diesters of glutamic acid are stable in dioxane solution but decompose in the presence of carbon dioxide to yield pyroglutamic esters. This reaction represents an intramolecular aminolysis of an ester. Studying the kinetics of the reaction in the absence and presence of amines led to the conclusion that the catalyst of the system is an undissociated carbamic acid formed from the aminodiester and CO2. The catalysis proceeds by a two-centre push-pull mechanism. The proposed reaction mechanism explains the first order dependence on the CO2-pressure and the second order kinetics with respect to the substrate. The results obtained with the models are applied to the polymerization of LEUCHS-anhydrides of glutamates. The termination is rather unusual being a bimolecular reaction in which only one of the two chains is terminated.

The reaction of K2PtCl4 with CH3—CH=CH—CH2—OH yields the complex cis-[PtCl2((CH2=CH—CH(CH3))2O)]. The crystals are triclinic, space group [Formula: see text], a = 9.420(2) Å, b = 8.359(4) Å, c = 7.837(4) Å, α = 91.10(4)°, β = 62.13(4)°, γ = 80.80(5)°, and Z = 2. The structure, solved by standard methods, has been refined anisotropically by full matrix least-squares methods to a R factor of 0.052 by use of 2441 independent observed reflections. The complex is a monomer, where both double bonds of the diolefin ether are coordinated to the platinum atom as in Zeise's salt. The usual square planar coordination of platinum(II) is completed by two chlorine atoms. The (=CH2) groups of both double bonds are found on the same side of the coordination plane. Various possible conformations of the coordinated ligand in the complex are discussed.

Time-saving method of accurately calculating 5 of most difficult overhead conductor problems encountered is presented; method is based on empirical equations that can be solved with 10 in, log-log slide rule; for estimating work, equations may be used for quick approximate answers or for precise calculations when making charts or tables for field use; problems can be solved with less than 10% of time and effort required in conventional methods.