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1.
We consider general ferromagnetic spin systems with finite range interactions and an even single-spin distribution of compact support on IR. It is shown under mild assumptions on the single-spin distribution that a low temperature expansion, in powers ofT, for the free energy and the correlation functions is asymptotic. We also prove exponential clustering in the pure phases and analyticity of the free energy and of the correlation functions in the reciprocal temperature for Re large.Supported in part by N.S.F. Grant No. Phy. 78-15920 and MCS 78-01885On leave from: Départment de Physique Théorique, Université de Louvin, BelgiumSupported in part by the Swiss National Foundation for Scientific Research  相似文献   
2.
The Chemistry of Metal Carbonyls and Cyano Complexes in Liquid Ammonia. XXXI. On the Reactions of Cationic η5-Cyclopentadienyl-molybdenumcarbonyl Complexes with Liquid Ammonia Depending on the reaction conditions, the cationic complexes [η5-C5H5Mo(CO)3L]+ (L = NH3, PPh3, CO) react with liquid ammonia according to: The characteristics and reactivities of the new carbomoyl derivatives are described.  相似文献   
3.
We prove analyticity properties of correlation functions using correlation inequalities.  相似文献   
4.
Under fairly general conditions if a two dimensional classical lattice system has an internal symmetry groupG, which is a compact connected Lie group, then all Gibbs states areG-invariant.  相似文献   
5.
The Chemistry of Metal Carbonyls and Cyano Complexes in Liquid Ammonia. XXXII. On the Reaction of η5-C5H5Mo(CO)3CH3 and η5-C5H5Fe(CO)2CH3 with Liquid Ammonia η5-C5H5Mo(CO)3CH3 reacts with liquid NH3 to give η5-C5H5Mo(CO)2(NH3)H and acetamide: In contrast, η5-C5H5Fe(CO)2CH3 undergoes a carbonyl insertion to give the acetyl complex η5-C5H5Fe(CO)(NH3)COCH3: The NH3 ligand in η5-C5H5Fe(CO)(NH3)COCH3 can be substituted by pyridine.  相似文献   
6.
The depside-like esters 3a and 3b underwent a Smiles rearrangement on treatment with base. The resulting diphenyl ethers 4a and 4b were converted into the xanthonecarboxylic acids 6a and 6b which are not readily accessible by other routes.  相似文献   
7.
Various (hetero)arenecarboxylic acids were converted to the corresponding Daugulis amides and nitrated selectively in the ortho‐position in the presence of [CuNO3(PPh3)2] and AgNO2 at 50 °C. A microwave‐assisted saponification allows regenerating the carboxylate group within minutes, which may then be removed tracelessly by protodecarboxylation, or substituted by aryl‐ or alkoxy‐groups via decarboxylative cross‐coupling.  相似文献   
8.
For the semi-infinite Ising model in two or more dimensions, we prove analyticity properties of the surface free energy and map out the phase diagram in the absence of an external magnetic field. We prove that this phase diagram contains critical lines where the parallel and/or the transverse correlation lengths diverge. The critical exponent,v , of the transverse correlation length is shown to be equal to the exponentv of the Ising model on an infinite lattice. In a second paper, these results will be used to analyze the wetting transition.  相似文献   
9.
A series of experiments on the dynamic interaction of two current channels has been performed in the large plasma device, a laboratory device at UCLA. The two current channels are formed by coating the cathode source nonuniformly and then biasing it with respect to an anode 10 m away. The experiment consists of two phases, one in which a net current is drawn through the plasma, and one in which the net current is zero. The current channels twist about each other, merge, and evolve toward a force-free state when a net current is drawn through the plasma. When the net current is zero the interaction between the channels is greatly reduced. The dynamics of the system are dominated by electron pressure and associated electrostatic fields. However, as the currents twist, a small amount of magnetic helicity is generated. The helicity and its temporal rate of change are computed and found to compare within experimental uncertainty to the predicted rate  相似文献   
10.
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