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161.
Low-thermal-budget annealing of ion-implanted BF
2
+
, P, and As in Si was studied for shallow-junction formation. Implant doses were sufficient to amorphize the silicon surface
region. Low-temperature furnace annealing and rapid-thermal annealing of ionimplanted boron, phosphorus and arsenic in silicon
exhibit a transient enhanced diffusion regime resulting injunction depths considerably deeper than expected. The origin of
this transient enhanced diffusion is the annealing of ion-implantation damage in the silicon substrate. We have found that
point-defect generation during the annealing of either shallow end-of-range damage or small clusters of point defects dominates
the transient enhanced diffusion process depending upon the annealing temperature and time. The net effect of damage annealing
is to reduce the activation energy for dopant diffusion by an amount equal to the activation energy of the supersaturation
of point defects in silicon. Models which can describe the transient enhancement characteristics in dopant diffusion during
both furnace and rapid-thermal annealing of these implants are discussed. 相似文献
162.
Jean M. J. Tronchet Eva Winter-Mihaly Mohamed A. M. Massoud Olivier R. Martin Franoise Barbalat-Rey Joëlle Ojha-Poncet Josiane Giust 《Helvetica chimica acta》1981,64(7):2350-2355
CD.-Based Configurational Assignments of Glycosylaziridines The relationship between CD.-curves and the configuration of the trans-2-benzoyl-3-phenylaziridines was known. By studying a series of cis- and trans-2-glycosyl-3-benzoylaziridines we have shown that CD. allows the assignment of the configuration at both asymetric C-atoms. As benzoylaziridines can easily be obtained from cyano- or alkoxycarbonylaziridines without configurational change, the absolute configuration of these last two classes of compounds can also be assessed by this method. 相似文献
163.
We develop a model theoretic framework for studying algebraic structures equipped with a measure. The real line is used as
a value space and its usual arithmetical operations as connectives. Integration is used as a quantifier. We extend some basic
results of pure model theory to this context and characterize measurable sets in terms of zero-sets of formulas.
相似文献
164.
The concept of left character Connes-amenability for a dual Banach algebra \({\mathcal {A}}\) is introduced. We obtain a cohomological characterization of left character Connes-amenability as well as the relation between left \(\varphi \)-Connes-amenability and existence of left \(\varphi \)-normal virtual diagonals for a \(\omega ^{*}\)-continuous character \(\varphi \). We prove that left character amenability of \({\mathcal {A}}\) is equivalent to left character Connes-amenability of \({\mathcal {A}}^{**}\) when \({\mathcal {A}}\) is Arens regular. Moreover for a locally compact group G, we show that M(G) is left character Connes-amenable. In addition by means of some examples we show that for the new notion, the corresponding class of dual Banach algebras is larger than Connes-amenable dual Banach algebras. 相似文献
165.
Massoud Amini 《Monatshefte für Mathematik》2013,169(3-4):267-284
In this paper we introduce the notions of [I N] and [S I N]-hypergroups and prove a Choquet-Deny type theorem for [I N] and central hypergroups. More precisely, we prove a Liouville theorem for bounded harmonic functions on a class of [I N]-hypergroups. Further, we show that positive harmonic functions on [I N]-hypergroups are integrals of exponential functions. Similar results are proved for [S I N] and central hypergroups. 相似文献
166.
Kamran Divaani-Aazar Mohammad Ali Esmkhani Massoud Tousi 《Proceedings of the American Mathematical Society》2006,134(10):2817-2822
Let be a commutative ring with identity and an -module. It is shown that if is pure injective, then is isomorphic to a direct summand of the direct product of a family of finitely embedded modules. As a result, it follows that if is Noetherian, then is pure injective if and only if is isomorphic to a direct summand of the direct product of a family of Artinian modules. Moreover, it is proved that is pure injective if and only if there is a family of -algebras which are finitely presented as -modules, such that is isomorphic to a direct summand of a module of the form , where for each , is an injective -module.
167.
168.
Conditions are determined under which the minimum and/or characteristic polynomials of a matrix have simple zeros. 相似文献
169.
Sedaghati Saeb Azizian Homa Montazer Mohammad Nazari Mohammadi-Khanaposhtani Maryam Asadi Mehdi Moradkhani Fatemeh Ardestani Mehdi Shafiee Asgari Mohammad Sadegh Yahya-Meymandi Azadeh Biglar Mahmood Larijani Bagher Sadat-Ebrahimi Seyed Esmaeil Foroumadi Alireza Amanlou Massoud Mahdavi Mohammad 《Structural chemistry》2021,32(1):37-48
Structural Chemistry - A novel series of (thio)barbituric-phenoxy-N-phenylacetamide derivatives 7a-l was synthesized and evaluated against Helicobacter pylori urease. The latter assay revealed that... 相似文献
170.
The acid-catalysed hydrolysis of [Co(trpn)(CO3)]+ and [Co(trpn)(HCO3)]2+ ions (trpn = 3,3,3-triaminotripropylamine) have been studied spectrophotometrically in aqueous 1.0m HClO4/NaClO4. For the carbonato complex, [HClO4] = 0.02–0.25m and T = 20–35°C; for the bicarbonato complex, [HClO4] = 0.025–0.30m and T = 25°C. Both complexes hydrolyse to form the same cis-diaqua species. The rate law for the hydrolysis is d(ln[CoIII])/dt = k0+k1[H3O+]. The values of the rate constants (25°C), H (kJmol–1) and S (Jmol–1K–1)are:[Co(trpn)(CO3)]+,k0 = (1.7±0.6)× 10–4s–1, H 0 = 57±21, S 0 = –126±75; k1 = (1.0 ±0.1)×10–2m–1s–1, HDagger;1 = 62±8, S1 = –75 ±21, and for [Co(trpn)(HCO3)]2+, k0 = (2.9±0.7)× 10–4s–1, and k1 = (7.8±1.0)×10–2m–1s–1. The carbonato complex exhibits a deuterium isotope effect with k1D/k1H = 1.9, consistent with a rapid pre-equilibrium protonation, followed by rate-controlling ring-opening. The rate constants k0 and k1 (25°C and = 1.0m) for the ring-opening decarboxylation of the two systems studied lie within the experimental error. The results are compared with o ther related systems and the factors which influence the ring-opening decarboxylation (steric hindrance, ring strain, electron-donor ability of the amines) are discussed. The k1 path is interpreted in terms of concerted ring-opening and bond-making in the highly unstable aquabicarbonato intermediate. 相似文献