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41.
The thermal stress around the sodium level of the LMFBR reactor vessel, caused by the axial temperature distribution during heat-up and cool-down transient conditions, is one of the most important problems for a reactor vessel designer, especially in a conceptual design stage. Key parameters relating to plant operating transient conditions and reactor vessel main configuration should be settled carefully, thermal stresses not being allowed to exceed design stress limits. In order to examine the sodium level thermal stress easily and economically, a simple computer program for parameter survey has been developed. This program uses a one-dimensional Fourier series solution in transient temperature distribution analysis, and an analytical stress solution based on shell theory in stress value estimation. This paper presents a simplified and economical calculation method for the axial temperature distribution and stress value in the LMFBR operating transient conditions, and analysis examples obtained with this computer program.
Paper presented at the World Conference on Thermal Analysis, Madeira (Portugal) 1986. 相似文献
Zusammenfassung Der durch die axiale Temperaturverteilung während der Übergangsphase von Aufheizen und Abkühlen verursachte thermische Streß rund um den Natriumfüllstand des LMFBR-Reaktorkessels ist für den Reaktorkesselkonstrukteur, besonders im Entwurfstadiuni eines der wichtigsten Probleme. Die mit den transienten Operationsbedingungen der Anlage und der Gestaltung des Reaktorkessels in Beziehung stehenden Grundparameter müssen sorgfältig ermittelt werden, um zu verhindern, daß der thermische Streß die geplanten Streßgrenzen nicht überschreitet. Um den thermischen Streß um den Natriumfüllstand, leicht und ökonomisch zu bestimmen, wurde ein Komputerprogramm für die Parameterübersicht aufgestellt. In diesem Programm wird von einer eindimensionalen Fourrierreihe zur Analyse der transienten Temperaturverteilung und einer auf der Schalentheorie von Streßwertbestimmungen basierende analytische Lösung Gebrauch gemacht. Im vorliegenden Artikel werden eine vereinfachte und wirtschaftliche Berechnungsmethode für die axiale Temperaturverteilung und Streßwerte bei transienten Arbeitsbedingungen mitgeteilt und mit diesem Komputerprogramm ausgeführte Analysenbeispiele angegeben.
, - () , , , . , , , . , , - , . , , .
Paper presented at the World Conference on Thermal Analysis, Madeira (Portugal) 1986. 相似文献
42.
T Nishi M Sakurai S Sato M Kataoka Y Morisawa 《Chemical & pharmaceutical bulletin》1989,37(8):2200-2203
An asymmetric synthetic route to 2-substituted-3-aminocarbonyl propionic acid, which is the significant component of low-molecular-weight renin inhibitors, is described. The key step of this synthesis is diastereoselective alkylation by using chiral oxazolidinone and benzyl bromoacetate. 相似文献
43.
44.
Summary The simultaneous stereospecific assay of four stereoisomers of diltiazem hydrochloride in bulk drug and aqueous solution was
developed using HPLC on a Chiralcel OF column. The four isomers were quantitated with good precision by the internal standard
method. The chiral inversion of (+)-cis-diltiazem hydrochloride in vitro, stability of its (2S, 3S) configuration in the solid
and aqueous states was examined by HPLC. Chiral inversion of (+)-cis-diltiazem hydrochloride was not observed in the solid
state, and its (2S, 3S) configuration was stable to heat, humidity and light. Chiral inversion of (+)-cis-diltiazem hydrochloride
(2S, 3S) was observed in aqueous solution under UV, but not in aqueous solution stored at 80°C for 5h nor under visible light
for 10 h. The (+)-cis-diltiazem hydrochloride (2S, 3S) epimerized to (+)-trans-diltiazem hydrochloride (2R, 3S) with a half-life
of 5h in aqueous solution under UV but the reverse chiral inversion of (+)-trans-diltiazem hydrochloride (2R, 3S) to (+)-cis-diltiazem
hydrochloride (2S, 3S) was not observed. 相似文献
45.
T Suzuki E Sato Y Matsuda H Tada K Unno T Kato 《Chemical & pharmaceutical bulletin》1989,37(4):1051-1054
Zein microspheres conjugated with antitumor drugs (mitomycinc (MMC), daunomycin hydrochloride (DM), peplomycin sulfate (PEP] were prepared by using a dimethyl sulfoxide (DMSO)-H2O system. MMC with low solubility in H2O was easily entrapped by the standard procedure, whereas some modifications were required for moderately and highly soluble drugs such as DM and PEP. Colorimetric determination of the drugs in microspheres was easily achieved by use of the phenol-sulfuric acid method for drugs with sugar moieties in their molecules, such as DM and PEP, while a simple treatment of the microspheres with concentrated sulfuric acid was applied in the case of drugs having a chromophore in their molecules, such as DM and MMC. 相似文献
46.
A sensitive and specific method using gas chromatography and negative-ion chemical ionization mass spectrometry is described for the determination of 5-fluoro-2'-deoxyuridine (FdUrd) in plasma. The method is based on the formation of the pentafluoropropionyl derivative of FdUrd and of its stable isotope as internal standard after sample clean-up by solid-phase extraction and purification by high-performance liquid chromatography. Quantification in plasma was possible down to 300 pg/ml. The method was applied to the analysis of plasma levels of FdUrd in mice and dogs. 相似文献
47.
Usefulness of three kinds of TSH kits by immunoradiometric assay (IRMA) was evaluated. They were able to measure low levels (less than 0.1 microIU/ml) in serum thyroid stimulating hormone (TSH) with incubation of short time (4 hours). In particular, RIABEAD II kit had a highly specific affinity for TSH and the normal range (+/- 2 S.D.) using it showed from 0.20 to 3.50 microIU/ml in 150 normal subjects. In patients with hyperthyroidism and in patients with hypothyroidism, the values of TSH were lower and higher than those of normal subjects, respectively. Another kits showed similar results. These results indicate that these TSH-IRMA kits are useful to evaluate serum TSH levels exactly. 相似文献
48.
Phosphorus-containing polyanhydride-imides were synthesized from N,N-bis(4-carboxyphthalimido)-3,3′-diphenylalkylphosphine oxide, 3,3′-[N,N′-bis(4-carboxyphthalimido)]benzophenone and their mixtures in two steps via the diacetyl derivatives of the bisimide-carboxylic acids. The resulting polymers have reduced viscosities of 0.06–0.14 dl/g and are soluble in polar aprotic solvents such as DMA, DMF and DMSO, and conc. H2SO4 etc. They have good hydrolytic stability for moisture and water. Phosphorus-containing polymers have little heat-resistance and poor flame-retardance. The benefit of incorporating phosphorus in the polymers is small. 相似文献
49.
T. Miyamoto Y. Sato T. Shibata H. Inagaki M. Tanahashi 《Journal of polymer science. Part A, Polymer chemistry》1984,22(10):2363-2370
13C-NMR spectra of ring carbons and O-acetyl carbonyl carbons of cellulose acetate (CA) in dimethyl sulfoxide-d6 were analyzed. The CA samples with the degree of substitution (DS) ranging from 0.84 and 1.91 were prepared by homogeneous acetylation of cellulose with acetic anhydride in a 10% LiCl/dimethyl acetamide solvent. It was found that the use of these low DS samples permitted easier assignments not only of the ring carbon but also of the O-acetyl carbonyl carbon signals. The assignments were confirmed by comparing with the 1H-NMR spectra of the samples obtained by complete acetylation of the corresponding CA samples with acetyl-d3 chloride. Two methods for determining the distribution of O-acetyl groups of CA, i.e., the relative DS at the three different types of hydroxyl groups, were developed. One is based on the measurements of the relative intensities of the signals for the ring carbons and the other is based on the measurements of the relative intensities of the signals for the O-acetyl carbonyl carbons. 相似文献
50.
[2.2]Metacyclophane (1) undergoes a variety of reactions according to the reagents and conditions. These include (1) substitution (path a), (2) transannular dehydrogenation (path b and c), (3) cycloisomerization (path d) and (4) transannular hydrogenation. A brief summary of these reactions is presented.The diversity of the reactions of 1 is further explored using benzoyl peroxide (BPO), cupric chloride, aluminum chloride, other metal salts, H2SO4 and FSO3H. With BPO or cupric chloride, one-electron transfer mechanism is postulated. This involves a tautomeric ion pair formed by the intramolecular arylation with an aryl cation radical. A supporting evidence in favor of the mechanism is presented from experiments using various metal salts in different solvents.On the contrary, the reaction with aluminum chloride gives decahydropyrene (8) and octahydropyrene (11) together with cycloisomerization product 5 and dehydrogenation products 2, 3 and 4. When treated with AlCl3HCl 1 gives similar products as above but the product ratios are quite different. The major product is 5 but only a trace amount of 8 is formed. The reaction with H2SO4 or FSO3H also produce 2, 4, 5 and 11. Some mechanistic evidence in favor of the disproportionation reaction is presented. 相似文献