PL
 |
EN
Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl
Preferencje help
Polish version English version Język
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 11

Liczba wyników na stronie
first rewind previous Strona / 1 next fast forward last
Wyniki wyszukiwania
Wyszukiwano:
w słowach kluczowych:  nitration
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 1 next fast forward last
1
Nitrated coals as active carbon precursors.
100%
Tamarkina Y. V. , Shendrik T. G.
|
|
tom Vol. 10, nr 57
75-80
EN
It has been studied the interaction of coals ranging from brown coal (Cdaf=70.4%) to anthracite (Cdaf=95.2%), with equimolar nitrating system HNO3-Ac2O (20-2C) yielding nitrated coals named as structurally modified coals (SMCs). In comparison with the parent coals, SMCs have more disordered structures contain aromatic NO2 groups and different oxygen functionalities as substitutes. Besides, SMCs are more thermolabile comparing with parent coals. Nitrated coals are better precursors of active carbons and may be activated by KOH into adsorbents with surface area as high as 1200 in 2/g.
2
Content available remote Preparation of Low-melting Compositions Based on 1,3,3-Trinitroazetidine
100%
Katorov D. V. , Rudakov G. F. , Ladonin A. V. , Zhilin V. F. , Veselova E. V. , Vyalova N. A.
|
2007
|
tom Vol. 4, nr 1-2
125-133
EN
Investigations of TNAZ/AzDNAZ mixtures with different TNAZ contents revealed an eutectic composition TNAZ/35/65 with melting point of 61 C. Combined introduction of nitro- and azido groups followed by nitration of tBuDNAZ/tBuAzNAZ mixtures in N2O5/CH3CN and NH4NO3/(CH3CO)2O systems has been investigated. Possibility of synthesis TNAZ/AzDNAZ mixtures of various contents has been shown.
3
Content available A Study of the Synthesis and Amination of 2,6-Dialkoxy-3,5-dinitropyrazines
88%
Bellamy A. J. , Golding P.
|
2008
|
tom Vol. 5, nr 2
3-19
EN
A series of 2,6-dialkoxy-3,5-dinitropyrazines (R = Me, Et, Pr) has been synthesized and subjected to amination. The yield and purity of the generated 2,6-diamino-3 ,5-dinitropyrazine was found to be independent of the alkoxy group present in the precursor. This contrasts with the behaviour of 1,3,5-trialkoxy-2,4,6-trinitrobenzene (R = Me, Et, Pr), where the purity of the 1,3,5-triamino- 2,4,6-trinitrobenzene (TATB) produced by amination was very dependent upon the alkoxy group.
4
Content available remote Nitration of Toluene and Chlorobenzene with HNO3/Ac2O Catalyzed by Caprolactam-based Bronsted Acidic Ionic Liquids
88%
Ql X. , Cheng G. , Lu C. , Qian D.
|
2007
|
tom Vol. 4, nr 3
105-113
EN
Several new caprolactam-based Bronsted acidic ionic liquids [Caprolactam]X (X- = pTSO-, BSO-, BF4-, NO3-) with relatively lower cost and lower toxicity were synthesized and for the first time used in catalyzing organic reaction. They showed good catalytic activity in the nitration of toluene and chlorobenzene with HNO3/Ac2O under mild conditions. Among them, [Caprolactam]pTSO was the best one probably because of its better affinity to aromatics than the others. [Caprolactam]pTSO catalyzed the nitration of toluene with achieving a high yield (99.7%, calculated by quantitative GC) and better para-selectivity (ortho/para=1.03) than the traditional mixed acid methodology. And the catalyst can be recycled for four times.
5
Content available remote The Study of Some Potential New Synthetic Routes to LLM-105 (2,6-Diamino-3,5-dinitropyrazine 1-oxide)
88%
Bellamy A. J. , Golding P.
|
2007
|
tom Vol. 4, nr 3
33-57
EN
The synthesis of LLM-105 (2,6-diamino-3,5-dinitropyrazine 1-oxide) via the direct nitration of 2,6-diaminopyrazine 1-oxide is reported. Two synthetic routes to the starting material 2,6-diaminopyrazine 1-oxide have been investigated. The synthesis of 2,6-diamino-3,5-dinitropyrazine by nitration of 2,6-diaminopyrazine and 2,6-diacetamidopyrazine has also been studied. Whilst mono-nitration of 2,6-diaminopyrazine is very selective, further nitration leads to mixtures of 2,6-diamino-3,5-dinitropyrazine, 6-amino-2-keto-3,5-dinitropyrazine and tetraketopiperazine, the latter predominating in many cases. It was shown that tetraketopiperazine is formed by further reaction of the initially formed 2,6-diamino-3,5-dinitropyrazine. Nitration of 2,6-diacetamidopyrazine does furnish 2,6-diamino-3,5-dinitropyrazine, but the yield is poor.
6
Structure Determination of Some Nitro-5,10,15,20-tetrakis(3-methoxyphenyl)porphyrins Using Simple NMR Techniques
88%
Ostrowski S. , Łopuszyńska B. , Mikus A.
|
2006
|
tom Vol. 80, nr 7
1209-1215
EN
The structures of some nitrosubstituted meso-tetraarylporphyrins were determined by a simple comparison of their 1H NMRspectra, and confirmed by NOE experiments. On the basis of these investigations it was found that in the meso-tetraphenylporphyrin (meso-TPP) and its 3-methoxy, 3-methyl, and 3-chloro-substituted derivatives (in the meso-aryl rings), the electrophilic nitration occurred in position 4-.
7
Study on the Synthesis, Reduction and Reductive Amination of Nitroindan-1-ones. Preparation of N-beta-Hydroxyethyl Derivatives of 6-Aminoindan-1-one and Indan-1,6-diamine
75%
Wodnicka A. , Kwiecień H.
|
2008
|
tom Vol. 82, nr 11
2133-2140
EN
Synthesis of 6-aminoindan-1-one and 7-amino-5,6-dimethoxyindan-1-one by nitration of corresponding indanones, followed by selective palladium catalyzed reduction under mild conditions has been described. Reactions of the amines with oxirane leading to N,N-bis-(beta-hydroxyethyl) derivatives were performed. The study of reductive amination of 6-nitroindan-1-one and 5,6-dimethoxy-7-nitroindan-1-one via azines to the corresponding amines as well as synthesis of N,N-bis-(beta-hydroxyethyl) derivatives of the amines was also described.
8
Content available remote Synteza 1-R-nitroetenów
63%
Jasiński R. , Mikulska M. , Barański A.
|
2009
|
tom Vol. 62, nr 4
154-164
PL
W artykule usystematyzowano stan wiedzy na temat metod syntezy 1-R-1-nitroetenów. Syntezy te można podzielić na trzy grupy związane z: utworzeniem wiązania podwójnego w nitrozwiązkach nasyconych, wprowadzeniem grupy nitrowej do związku zawierającego podwójne wiązanie pomiędzy atomami węgla oraz modyfikacją struktury cząsteczek posiadających układ nitrowinylowy.
EN
In the presented work was systemized state of knowledge about the synthesis method of 1-R-1-nitroethenes. These syntheses can be divided into three groups: creation of double bond in the saturated nitro compounds, introduction of nitro group into compounds including double bond between carbon atoms as well as modification of molecule structure hawing nitrovinylic system.
9
Content available remote Mikroreaktor krzemowo-szklany do syntezy 2-izopropoksy-5- nitrobenzaldehydu
63%
Knapkiewicz P. , Skowerski K. , Jaskólska D. E. D. E. , Kowalski P. , Olszewski T.
|
2012
|
tom R. 88, nr 10b
98-100
PL
W niniejszym artykule przedstawiono mikroreaktor krzemowo-szklany oraz jego zastosowanie w reakcji selektywnego nitrowania 2- izopropoksy benzaldehydu do 2-izopropoksy-5-nitrobenzaldehydu, ważnego elementu budulcowego nitrowego katalizatora metatezy olefin typu Hoveydy-Grubbsa. Mikroreaktor wykonano technikami mikroinżynieryjnymi z krzemu i szkła, materiałów odpornych na środowisko nitrowania. Dodatkowo mikroreaktor wyposażono w miniaturowe czujniki temperatury oraz zaplanowano wykorzystanie miniaturowych, odpornych na korozję czujników ciśnienia.
EN
Herein we describe a flow-through silicon-glass microreactor and its application in selective nitration of 2-isopropoxybenzaldehyde to 2- isopropoxy-5-nitrobenzaldehyde, important building block of nitro-substituted metathesis catalyst of type Hoveyda-Grubbs. The flow-through microreactor was fabricated using microengineering techniques from silicon and glass, materials resistant to nitration environment. Microreactor is equipped with miniature temperature sensors and with resistant to corrosion pressure sensors.
10
Filtracja zawiesiny ponitracyjnej
63%
Budzyński P. , Dziubiński M.
|
2003
|
tom Nr 1
8-9
EN
Filtration of a nitration suspension, extremely dangerous because of its explosiveness and chemical aggressiveness, was studied. The parameters of filter cloths necessary to accomplish such a filtration, constants of the filtration carried out at constant pressure, and compressibility factor of the precipitata were determined. They enable designing of filtration parameters in an industrial scale. -
11
Content available remote Peroxynitrite mediated linoleic acid oxidation and tyrosine nitration in the presence of synthetic neuromelanins.
63%
Stępień K. , Wilczok A. , Zajdel A. , Dzierżęga-Lęcznar A. , Wilczok T.
Acta Biochimica Polonica
|
2000
|
tom 47
|
nr 4
931-940
EN
Peroxynitrite-mediated linoleic acid oxidation and tyrosine nitration were analysed in the presence of synthetic model neuromelanins: dopamine (DA) -melanin, cysteinyldopamine (CysDA) -melanin and various DA/CysDA copolymers. The presence of melanin significantly decreased the amount of 3-nitrotyrosine formed. This inhibitory effect depended on the type and concentration of melanin polymer. It was found that incorporation of CysDA-derived units into melanin attenuated its protective effect on tyrosine nitration induced by peroxynitrite. In the presence of bicarbonate, the melanins also inhibited 3-nitrotyrosine formation in a concentration dependent manner, although the extent of inhibition was lower than in the absence of bicarbonate. The tested melanins inhibited peroxynitrite-induced formation of linoleic acid hydroperoxides, both in the absence and in the presence of bicarbonate. In the presence of bicarbonate, among the oxidation products appeared 4-hydroxynonenal (HNE). CysDA-melanin inhibited the formation of HNE, while DA-melanin did not affect the aldehyde level. The results of the presented study suggest that neuromelanin can act as a natural scavenger of peroxynitrite.
first rewind previous Strona / 1 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.