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101.
H. E. Marsh JR. 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(7):1397-1418
Abstract The complex and important role of the propellant binder in solid-propellant rockets is described. The severe weight problems of space exploratrion cause high propellant performance to be of major concern in a highly competitive field. Binders contribute to performance, not only in terms of fuel value, but by being compatible with energetic components and by providing good mechanical properties. Both sterilization required for planetary landings and compatibility problems of new energetic oxidizers generate new requirements too stringent for existing binders; only binders composed essentially of saturated aliphatic hydrocarbon are predicted to be suitable. Several saturated-binder developments are in progress. The achievements of one of these programs, based on free-radical synthesis, are evaluated against the goals of the new binder. 相似文献
102.
For K a set of topological spaces and X,Y∈K, the notation Xh⊆Y means that X embeds homeomorphically into Y; and X∼Y means Xh⊆Yh⊆X. With , the equivalence relation ∼ on K induces a partial order h? well-defined on K/∼ as follows: if Xh⊆Y.For posets (P,P?) and (Q,Q?), the notation (P,P?)?(Q,Q?) means: there is an injection such that p0P?p1 in P if and only if h(p0)Q?h(p1) in Q. For κ an infinite cardinal, a poset (Q,Q?) is a κ-universal poset if every poset (P,P?) with |P|?κ satisfies (P,P?)?(Q,Q?).The authors prove two theorems which improve and extend results from the extensive relevant literature.
Theorem 2.2.
There is a zero-dimensional Hausdorff space S with|S|=κsuch that(P(S)/∼,h?)is a κ-universal poset. 相似文献
103.
104.
K.E. Rehm P. Kienle D.W. Miller R.E. Segel J.R. Comfort 《Physics letters. [Part B]》1982,114(1):15-18
Differential cross sections and analyzing powers were measured for inelastic scattering of 160 MeV protons to the 48Ca 10.24 MeV, 1+ state. DWIA calculations with shell-model wave functions which fit inelastic electron scattering form factors predict too much cross section at small q and too little at large q for inelastic proton scattering. These results are consistent with the q-dependent modification of magnetic transitions anticipated from mesonic effects such as virtual Δ(1232)-hole excitations. 相似文献
105.
Alves GA Amato S Anjos JC Appel JA Bracker SB Cremaldi LM Darling CL Dixon RL Errede D Fenker HC Gay C Green DR Jedicke R Kaplan D Karchin PE Kwan S Leedom I Lueking LH Luste GJ Mantsch PM de Mello Neto JR Metheny J Milburn RH de Miranda JM da Motta Filho H Napier A d'Olivera AB Rafatian A dos Reis AC Reucroft S Ross WR Santoro AF Sheaff M Souza MH Spalding WJ Stoughton C Streetman ME Summers DJ Takach SF Wu Z 《Physical review letters》1992,69(22):3147-3150
106.
107.
De La Fuente JR Canete A Zanocco AL Saitz C Jullian C 《The Journal of organic chemistry》2000,65(23):7949-7958
The photophysical and photochemical behavior of 1-methyl-3-phenylquinoxalin-2-one (MeNQ) and 3-phenylquinoxalin-2-one (HNQ) in the presence of amines is reported. While HNQ fluorescence shows an auxochromic effect and a bathochromic shift with added amines, explained by association of HNQ with amine in the ground state and emission from both excited species HNQ and [HNQ-amine], both MeNQ and HNQ are photoreduced efficiently on irradiation in the presence of amines, leading to the semireduced quinoxalin-2-ones, MeNQH(-) and HNQH(-), respectively, via an electron-proton-electron transfer, with unit quantum yields at high amine concentrations. The semireduced quinoxalin-2-ones XNQH(-) (X = H, Me) revert almost quantitatively to the parent XNQ in a dark thermal reaction with an activation free energy for MeNQH(-) of 17.4 and 25.9 kcal/mol in acetonitrile and benzene, respectively. Kinetic and spectroscopic (UV and NMR) evidence supports the proposed reaction mechanism for the reversible photoreduction. 相似文献
108.
Abstract— Absorption and emission spectra of several N-arylbenzamides have been measured. The quantum yields for their fluorescence were found to be dependent on matrix viscosity and temperature. Singlet-triplet splittings for these compounds were determined from their emission spectra and found to be abnormally small for π. π* states (˜ 1500 cm-1 ). Indeed, the phosphorescence maxima of N-arylbenzamides occur slightly to the blue relative to their fluorescence maxima. Intersystem crossing efficiencies were determined for several of these compounds and are consistent with S1 → S 0 radiationless decay. 相似文献
109.
Ferro-Luzzi M Bouwhuis M Passchier E Zhou Z Alarcon R Anghinolfi M van Bommel R Botto T van den Brand JF Buchholz M Bulten HJ Choi S Comfort J Dolfini S Ent R Gaulard C Higinbotham D de Jager CW van Klaveren EP Konstantinov E Lang J de Lange DJ Miller MA Nikolenko D Nooren GJ Papadakis N Passchier I Poolman HR Popov SG Rachek I Ripani M Six E Steijger JJ Taiuti M Unal O Vodanis N de Vries H 《Physical review letters》1996,77(13):2630-2633
110.
Aitala EM Amato S Anjos JC Appel JA Ashery D Banerjee S Bediaga I Blaylock G Bracker SB Burchat PR Burnstein RA Carter T Carvalho HS Costa I Cremaldi LM Darling C Denisenko K Fernandez A Gagnon P Gerzon S Gobel C Gounder K Granite D Halling AM Herrera G Hurvits G James C Kasper PA Kondakis N Kwan S Langs DC Leslie J Lichtenstadt J Lundberg B Manacero A MayTal-Beck S Meadows B de Mello Neto JR Milburn RH de Miranda JM Napier A Nguyen A d'Oliveira AB O'Shaughnessy K Peng KC Perera LP Purohit MV 《Physical review letters》1996,76(3):364-367