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101.
Arithmetic formulae and an asymptotic expression for the order of magnitude of the arithmetic function ged (s, n) and of a generalisation of it are derived.  相似文献   
102.
It is shown by a simple induction that any square-free natural number is the square-free kernel of Euler's -function of infinitely many natural numbers. Furthermore every square-free natural number >1 is the square-free kernel of Euler's -function of infinitely many square-numbers.  相似文献   
103.
The classical Gauss-Bonnet formula has the form I(gij)=2, where I(gij) represents a sum of three terms each of which depends on the metric tensor gij. It is shown that the first variation I of I(gij) with respect to the metric gij vanishes and that for the Euclidean metric ij we have I(ij)=2. From this the formula I(gij)=2 follows. In the process, explicit expressions are obtained for the first variation of each of the three terms which comprise I(gij). Furthermore, a general expression for the first variation of a multiple integral whose integrand is a scalar density depending on the metric tensor gij and its derivatives up to the second order is obtained with the aid of results of Rund [1].  相似文献   
104.
105.
The direct determination of CO2 is often faulty because of certain contents of the natural water. Due to this reason a specific method was worked out. The water to be analysed and distilled water are placed side by side in a gas-tight vessel with an atmosphere free of CO2, whereby mixing is avoided but gas-exchange is possible. After adjustment to the gas-equilibration the CO2 content of the distilled water is determined e.g. by titration, measuring of conductivity or other methods, from where the CO2 content in the natural water is calculated.  相似文献   
106.
Carbonyldinitrosyltris(fluorosulfato)tungstate(II) and ‐molybdate‐(II) anions, [fac‐M(CO)(NO)2(SO3F)3]? (M=W, Mo), which are novel weakly coordinating anions that contain a metal carbonyl/nitrosyl moiety, have been generated in fluorosulfonic acid and completely characterized by multinuclear NMR, IR, and Raman spectroscopy as well as ESI mass spectrometry. ESI MS measurements performed for the first time on a superacidic solution system unambiguously reveal the formation of the monoanionic, mononuclear W and Mo complexes formulated as [M(CO)(NO)2(SO3F)3]? (M=W, Mo). Multinuclear NMR spectroscopic studies at natural abundance and 13C and 15N enrichment clearly indicate the presence of one CO ligand, two equivalent NO ligands, and two types of nonequivalent SO3F? groups in a 2:1 ratio. The IR and Raman spectra reveal that the two equivalent NO ligands have a cis conformation, thus indicating a fac structure. Density functional calculations at the B3LYP level of theory predict that these anions have a singlet ground state (1A′) with a Cs symmetry along with C–O and N–O vibrational frequencies that are in agreement with the experimental observations. Mulliken population analysis shows that the monovalent negative charge is dispersed on the bulky sphere, the surface of which is covered by all the negatively charged O and F atoms with charge densities much lower than SO3F?, suggesting that [fac‐M(CO)(NO)2(SO3F)3]? (M=W, Mo) are weakly nucleophilic and poorly coordinating anions.  相似文献   
107.
This paper presents anew design concept for a gamma irradiation plant for the continuous processing of pumpable liquids. Typical applications of such a plant include
• * the irradiation vulcanisation of natural latex rubber
• * disinfection of municipal sewage sludge for agricultural use
• * sterilisation of liquids in the pharmaceutical and cosmetics industries
• * industrial processing of bulk liquids

The authors describe the design and operation of the latex irradiator now operating on a small production scale in Malaysia and proposed developments.

The design allows irradiation processing to be carried out under an inert or other gaseous environment.

State-of-the-art computer control system ensures the fully automatic processing operation needed by industrial computers.  相似文献   

108.
Summary The depressions in freezing point measurements in quaternary solubilized solutions or micro-emulsion in sodium oleate + phenol + benzene + water are measured. Maxima and minima were observed, Gibbs' phase rule was applicable, eutectic points were detected, congruent melting points were obtained, loose combination of molecules or clusters, were formed, phases of the system transferred and finally unstable emulsion separated out. This is contrary to the views ofMcBain who called these solutions as thermodynamically stable. The results were compared with the conductivity, stability and heat of solubilization-concentration measurements.
Zusammenfassung Es wird die Gefrierpunktserniedrigung von quaternären solubilisierten Lösungen im System Natriumoleat-Phenol-Benzol-Wasser gemessen. Die verschiedenen Befunde (Maxima und Minima des Gefrierpunktes in Abhängigkeit von der Zusammensetzung, Anwendbarkeit der Gibbs'schen Phasenregel, Auftreten von Eutektika, kongruente Schmelzpunkte etc.) dienen zum Beweis, daß diese Lösungen thermodynamisch instabil sind.


With 5 figures and 1 table  相似文献   
109.
Summary A thermodynamic treatment of homo-polymer systems out of linear chains with folded chain crystals is developed outgoing from appropriate models for single component systems. An expansion of thermodynamics to multi-micro-phase systems the structure of which is partially or totaly frozen is indispensable. General properties of melt crystallized homopolymers with folded chain crystals can be recognized indeed when the thermodynamic formalisms developed are applied.
Zusammenfassung Das Schmelzen in polymeren Einteilchensystemen mit Faltungskristallen einheitlicher Dicke kann thermodynamisch als Umwandlung 1. Ordnung in einer Richtung behandelt werden, wenn die Faltungslänge bis zur Umwandlungstemperatur konstant bleibt (Faltungslänge als innerer Zusatzparameter). Eine wesentliche begriffliche Erweiterung ist für eine phänomenologische Beschreibung mit den Mitteln der Thermodynamik unumgänglich, wenn eine Faltungskristallit-Dickenverteilung existiert, weil dann prinzipiell nur noch partielle Koexistenz bestimmter Fraktionen metastabiler autonomer Mikrophasen mit der Schmelze möglich ist. Partielles Aufschmelzen und Rektistallisation können so dann auch in Betracht genommen werden. Die entwickelten Konzeptionen bewähren sich in der Anwendung auf bekannte Experimente.

Notation g c (y);g m (Y) molar Gibbs-free energy of a chain of a lengthy within an extended chain crystal and the melt rsp - g o c ;g o m molar free enthalpy of the unit in the crystal lattice and the melt rsp - g(y,y, f) molar Gibbs-function of an ideally folded chain crystal with the fold heighty f - gco(y, y ef,y f) molar free enthalpy of the crystal corey co - g 0 ex ((yef) excess free enthalpy of the longitudinal layers of folded chain crystals - g f(yef,g o ex ) molar free enthalpy of the longitudinal layers of the folded chain crystals - g tot molar free enthalpy of a chain of the lengthy within a folded chain crystal with longitudinal layers - h o 1c ,h o m molar enthalpy of the chain unit within the crystal lattice and the melt rsp - h =h o m -h o c molar heat of fusion of the unit - C p=C p m -C p c difference of the molar specific heat of a unit within the melt and within the chain crystal - h D molar defect enthalpy of local defects within the crystal lattice - h D molar defect enthalpy of the unit - s o c ,s o m molar entropy of the chain unit within the crystal lattice and the melt rsp - s c m conformational entropy of a chain in the melt - s gk conformational entropy of a chain of lengthy within a super-lattice as indicated in figure 5, - s molar entropy of fusion of the melt - s n c nematic configurational entropy - T absolute temperature - T M melting temperature of extended chain crystals of infinite size - T M(y) melting temperature of extended chain crystals containing only chains of the lengthy - T M (y, y f) melting temperatureof folded chain crystals of the thicknessy f composed of chains of the lengthy - T M(y f) melting temperature of folded chain crystals of the thicknessy fy - eh excess free enthalpy of the chain ends occupying crystallographic places - ef excess free enthalpy of a single fold loop - z coordination number of the lattice - 7 Euler's constant - R Boltzmann's constant - y number of chain units - y f height of lamelliform folded chain crystals - f=(y/y f - 1) number of fold loops of a chain of a lengthy when being built into a folded chain crystal of the thicknessy f - y co thickness of the crystal core of the simplified twophase model - y et average thickness of the surface layers of folded chain crystals - N c number of crystallized units of a chain of the lengthy - x c molar number of crystallized units of a chain of the lengthy - x nc molar number of noncrystallized units - excess free enthalpy parameter - (y f) thickness distribution of the fold heightsy f With 15 figures and 2 tables  相似文献   
110.
The title compounds7 are formed in a general reaction by heating β-isothiocyanoketones3 with primary amines in inert solvents, or by thermal elimination of water from tetrahydro-6-hydroxy-6-methyl-2(1H)-pyrimidinethiones5, also in inert solvents. The 1-alkyl compounds can also be prepared under similar conditions from α,β-unsaturated ketones by reaction with alkylammonium rhodanides. The NMR-spectra show that the 1-substituted dihydro-6-methyl-2(1H)-pyrimidinethiones are in tautomeric equilibrium with the tetrahydro-6-methylene-2(1H)-pyrimidinethiones13. The reactivity of 1-alkyl and 1-aryldihydro-6-methyl-2(1H)-pyrimidinethiones is similar to that of dihydro-4,4,6-trimethyl-2(1H)-pyrimidinethione7 j, although their ring stability is certainly less.  相似文献   
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