PRECOCIOUS TERMINATION OF “OBLIGATORY” DIAPAUSE IN FIELD-COLLECTED PUPAE OF ANTHERAEA POLYPHEMUS

1968 ◽  
Vol 100 (2) ◽  
pp. 134-139 ◽  
Author(s):  
A. Mansingh ◽  
B. N. Smallman
Keyword(s):  
Adult Development ◽  
Room Temperature ◽  
The Other ◽  
Mortality Factor ◽  
Natural Mortality ◽  
Antheraea Polyphemus ◽  
Other Hand ◽  
Heavy Mortality

AbstractAntheraea polyphemus Cramer pupae, collected in early August, were found to maintain adult development at room temperature and natural daylength of late August and early September. These pupae had almost no coldhardiness, and heavy mortality occurred in the group of pupae stored at 6 °C. On the other hand, the pupae of A. polyphemus collected in late September were in diapause and were perfectly coldhardy. The possible relationship between the date of pupation and the incidence of diapause, and its significance as a natural mortality factor, is discussed.

scholarly journals Synthesis of spiro[dihydropyridine-oxindoles] via three-component reaction of arylamine, isatin and cyclopentane-1,3-dione

2013 ◽  
Vol 9 ◽  
pp. 8-14 ◽  
Author(s):  
Yan Sun ◽  
Jing Sun ◽  
Chao-Guo Yan
Keyword(s):  
Acetic Acid ◽  
Reaction Mechanism ◽  
Room Temperature ◽  
The Other ◽  
Other Hand ◽  
Three Component Reaction ◽  
High Yields

A fast and convenient protocol for the synthesis of novel spiro[dihydropyridine-oxindole] derivatives in satisfactory yields was developed by the three-component reactions of arylamine, isatin and cyclopentane-1,3-dione in acetic acid at room temperature. On the other hand the condensation of isatin with two equivalents of cyclopentane-1,3-dione gave 3,3-bis(2-hydroxy-5-oxo-cyclopent-1-enyl)oxindole in high yields. The reaction mechanism and substrate scope of this novel reaction is briefly discussed.

Diversification of α–Ketoamides via Transamidation Reactions with Alkyl and Benzyl Amines at Room Temperature

2021 ◽  
Author(s):  
Shweta Singh ◽  
Sureshbabu Popuri ◽  
Qazi Mohammad Junaid ◽  
Sabiah Shahul Hameed ◽  
Jeyakumar Kandasamy
Keyword(s):  
Room Temperature ◽  
The Other ◽  
Alkyl Amines ◽  
Other Hand ◽  
Wide Range

A wide range of N-tosyl α–ketoamides underwent transamidation with various alkyl amines in the absence of catalyst, base, or additives. On the other hand, transamidation in N-Boc α–ketoamides is achieved...

Letters to the Editor

PEDIATRICS ◽  
1973 ◽  
Vol 52 (2) ◽  
pp. 309-309
Author(s):  
C. Warren Bierman
Keyword(s):  
Room Temperature ◽  
Skin Testing ◽  
The Other ◽  
Letters To The Editor ◽  
Other Hand ◽  
Number Of Patients ◽  
Testing Solution

Dr. Bergner is quite correct in pointing out that skin testing with a freshly prepared penicillin solution will select out only about 30% of patients who are anaphylacticly sensitive to penicillin.1 On the other hand, the use of a sterile solution of benzylpenicillin diluted with alkaline buffered saline (pH 7.6) and permitted to stand at room temperature for at least two weeks appreciably increases the number of patients so detected.2 We would agree that the availability of a penicilloyl polylysine (PPL) testing solution and a stabilized minor determinent mixture (MDM) would greatly enhance the armamentarium of the clinician to detect anaphylactic sensitivity to penicillin.3

Electrochemical Hydriding of Mg-Based Alloys

2011 ◽  
Vol 312-315 ◽  
pp. 882-887
Author(s):  
Dalibor Vojtěch ◽  
Vítězslav Knotek ◽  
Pavel Novák
Keyword(s):  
Hydrogen Storage ◽  
High Temperatures ◽  
Room Temperature ◽  
Hydrogen Atmosphere ◽  
The Other ◽  
High Hydrogen ◽  
Hydrogen Saturation ◽  
Other Hand ◽  
Mechanism And Kinetics ◽  
Storage Methods

Mg-based alloys are prospective materials for reversible hydrogen storage in the form of metallic hydrides. Usually, hydrogen saturation is carried out at high temperatures and high hydrogen pressures. This is the reason for the high cost of metallic hydrides in comparison with other hydrogen storage methods. Electrochemical hydriding, on the other hand, can be realized at room temperature. Moreover, this process does not need any hydrogen atmosphere. In the presented work, electrochemical hydriding of several Mg-Ni-Mm-based alloys (Mm = mishmetal) is performed. Hydriding efficiency, mechanism and kinetics are described. It is shown that the additions of Ni, Mm and the formation of eutectic structures support hydriding of alloys.

Synthesis and antibacterial activity of some 1-(2-propynyl) and 1-propadienyl derivatives of 1,4-dihydro-4-oxoquinoline-3-carboxylic acids and similar heterocycles

1991 ◽  
Vol 56 (2) ◽  
pp. 439-448 ◽  
Author(s):  
Stanislav Rádl ◽  
Lenka Kovářová ◽  
Jiří Holoubek
Keyword(s):  
Antibacterial Activity ◽  
Dimethyl Sulfoxide ◽  
Carboxylic Acids ◽  
Potassium Carbonate ◽  
Potassium Hydroxide ◽  
Room Temperature ◽  
Ethyl Esters ◽  
The Other ◽  
Other Hand ◽  
Derivatives Of

N-Alkylation of IIIa, IIIb, IIId - IIIf and 9-acridanone with 3-bromopropyne in dimethyl sulfoxide in the presence of potassium carbonate yielded N-(2-propynyl) derivatives IVa - IVe and VIa, respectively. Ethyl esters IVa, IVb, and IVe were hydrolyzed to IVf - IVh, respectively. Compounds IVf, IVg, IVctreated with bases yielded N-propadienyl derivatives Va - Vc. On the other hand 2-substituted compounds IVd and IVh did not change under the same conditions. Compound VIa treated with powdered potassium hydroxide in dimethyl sulfoxide at room temperature yielded N-(1-propynyl) derivative VII.

Detoxification of Citrinin and Ochratoxin A by Hydrogen Peroxide

1994 ◽  
Vol 77 (3) ◽  
pp. 631-637 ◽  
Author(s):  
Sophie G Fouler ◽  
Alka B Trivedi ◽  
Naofumi Kitabatake
Keyword(s):  
Hydrogen Peroxide ◽  
Ochratoxin A ◽  
Hela Cells ◽  
Room Temperature ◽  
The Other ◽  
Toxic Compound ◽  
Other Hand ◽  
Alkaline Conditions

Abstract The effects of hydrogen peroxide on citrinin and ochratoxin A toxicity were examined using HeLa cells. The citrinin was completely detoxified by prior incubation with 0.05% hydrogen peroxide for 30 min at room temperature, and the toxic compound(s) that resulted from heating citrinin at 100°C were also detoxified upon reheating it with hydrogen peroxide. On the other hand, ochratoxin A was not detoxified by hydrogen peroxide at room temperature, but its toxicity was reduced by heating ochratoxin A with hydrogen peroxide under alkaline conditions.

THE INFLUENCE OF SUBSTITUENTS ON THE EASE AND DIRECTION OF RING OPENING IN THE LiAlH4–AlCl3 REDUCTIVE CLEAVAGE OF SUBSTITUTED 1,3-DIOXOLANES

1964 ◽  
Vol 42 (5) ◽  
pp. 990-1004 ◽  
Author(s):  
B. E. Leggetter ◽  
R. K. Brown
Keyword(s):  
Electron Donor ◽  
Electron Acceptor ◽  
Ring Opening ◽  
Room Temperature ◽  
Reductive Cleavage ◽  
The Other ◽  
Ring Cleavage ◽  
Other Hand ◽  
Influence Of Substituents

The room temperature hydrogenolysis by LiAlH4–AlCl3 of ether solutions of a number of 1,3-dioxolanes has been studied.Electron donor substituents on the C2 atom of the ring accelerate while electron acceptor substituents on C2 retard the reductive ring cleavage. The same effect but to a lesser extent is observed when these substituents are attached to the C4 or C5 atom of the ring.When electron donor substituents are attached to C4, ring cleavage occurs predominantly at the C2—O bond remote from the C4 position. On the other hand, electron-withdrawing groups attached to C4 give predominantly scission of the C2—O bond closer to the C4-substituted position. In contrast to this marked control over the direction of ring cleavage exhibited by substituents on C4, those on C2 generally have little or no effect on the direction of ring opening.A mechanistic interpretation of the results is presented.

Total synthesis of the stemodane-type diterpenoids (±)-stemodin and (±)-maritimol. Formal total synthesis of (±)-stemodinone and (±)-2-desoxystemodinone

1985 ◽  
Vol 63 (12) ◽  
pp. 3418-3432 ◽  
Author(s):  
Edward Piers ◽  
Brian F. Abeysekera ◽  
David J. Herbert ◽  
Ian D. Suckling
Keyword(s):  
Total Synthesis ◽  
Room Temperature ◽  
The Other ◽  
Subsequent Reaction ◽  
Total Syntheses ◽  
Keto Esters ◽  
Other Hand ◽  
Synthetic Intermediates ◽  
Separation Of Mixtures ◽  
Hydrolysis Of

Total syntheses of the stemodane-type diterpenoids (±)-stemodin (2) and (±)-maritimol (4), as well as formal total syntheses of (±)-stemodinone (3) and (±)-2-desoxystemodinone (5), are described. The known ketol 12 was converted into the tricyclic enone 7. Photoaddition of aliène to 7 gave (96%) a mixture of the photoadducts 20–23 (40:51:6:3, respectively). Ozonolysis of 20, followed by treatment of the resultant dione 24 with MeONa–MeOH (room temperature, 2.5 h), provided the keto ester 26 (94%). Subjection of 21 to an identical sequence of reactions gave (86%) the same product 26. On the other hand, when the dione 25 was treated with MeONa–MeOH under much milder conditions (0 °C, 5 min), the isomeric keto esters 27 (39%) and 28 (33%) were produced. Both 27 and 28, upon reaction with MeONa–MeOH at room temperature, were converted efficiently into 26. Reduction (NaBH4 or Lisec-Bu3BH) of 26 provided separable mixtures of the ester alcohol 32 and the lactone 33, which could be transformed readily into the dimesylates 35 and 39, respectively. Reaction of 35 and 39 with NaCN in warm hexamethylphosphoramide afforded the dinitriles 37 and 40, both of which, upon treatment with t-BuOK in refluxing t-BuOH, produced the sameenaminonitrile 41. Acid hydrolysis of 41 provided the dione 42. Preparatively, compound 26 could be transformed conveniently into the dione 42 (52% overall yield) without separation of mixtures of isomeric synthetic intermediates. Treatment (CH2Cl2, −95 °C) of 42 with Mc3Sil–Et3N, followed by oxidation of the resultant products 46 and 47 with Pd(OAc)2 in acetonitrile, gave the bis enones 48 (67%) and 49 (19%). Compound 48 was converted into the dione 52 which, upon reaction with (i-PrO)3 TiMe in ether, provided an 86:14 mixture of the keto alcohols 53 and 54 (63% from 48). Reduction (NaBH4) of 53 afforded (±)-maritimol (4). On the other hand, conversion of the 86:14 mixture of 53 and 54 into the p-toluenesulfonylhydrazones 55 and subsequent reaction of 55 with NaH in refluxing toluene gave the alkene alcohols 56 (58%) and 57 (12%). Hydroboration–oxidation (9-BBN, refluxing tetrahydrofuran; NaOH, H2O2) of 56 afforded (88%) (±)-stemodin (2).

Dielectric Properties of Y2NiMnO6 Ceramics at Various Sintering Times and Temperatures

2015 ◽  
Vol 804 ◽  
pp. 16-20 ◽  
Author(s):  
Panakamon Deeyai ◽  
Thanapong Sareein ◽  
Bundit Putasaeng ◽  
Naphat Chathirat
Keyword(s):  
Dielectric Properties ◽  
Dielectric Loss ◽  
Dielectric Permittivity ◽  
Room Temperature ◽  
Sintering Temperature ◽  
Dielectric Constants ◽  
The Other ◽  
Other Hand ◽  
Low Sintering Temperature ◽  
Sintering Conditions

Dielectric properties of hydrothermally decomposed Y2NiMnO6 ceramics prepared under several sintering conditions were investigated at room temperature. As the results, dielectric constants at 200 Hz were found about 928 and 23x103 for samples sintered at 1000 and 1400 oC, respectively. The dielectric permittivity for samples sintered at 1400 oC for different sintering times from 6 to 24 hours have yielded the best dielectric permittivity value of 104. On the other hand, low sintering temperature had resulted in smaller dielectric loss in comparison to larger dielectric loss generally found in the ceramics with high sintering temperature.

Strength and Ductility of Ni3Al Alloyed with Boron and Substitutional Elements

1994 ◽  
Vol 364 ◽  
Author(s):  
K. Ishikawa ◽  
K. Aoki ◽  
T. Masumoto
Keyword(s):  
Mechanical Properties ◽  
Yield Strength ◽  
Tensile Test ◽  
Fracture Strength ◽  
Room Temperature ◽  
The Other ◽  
Other Hand ◽  
Strength And Ductility

AbstractThe effect of simultaneous alloying of boron (B) and the substitutional elements M on mechanical properties of Ni3Al was investigated by the tensile test at room temperature. The yield strength of Ni3Al+B increases by alloying with M except for Fe and Ga. In particular, it increases by alloying with Hf, Nb, W, Ta, Pd and Si. The fracture strength of Ni3Al+B increases by alloying with Pd, Ga, Si and Hf, but decreases with the other elements. Elongation of Ni3Al+B increases by alloying with Ga, Fe and Pd, but decreases with other elements. Hf and Pd is the effective element for the increase of the yield strength and the fracture strength of Ni3Al+B, respectively. Alloying with Hf leads to the increases of the yield strength and the fracture strength of Ni3Al+B, but to the lowering of elongation. On the other hand, alloying with Pd improves all mechanical properties, i.e. the yield strength, the fracture strength and elongation. On the contrary, alloying with Ti, V and Co leads to the lowering of mechanical properties of Ni3Al+B. The reason why ductility of Ni3Al+B is reduced by alloying with some elements M is discussed.

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