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91.
This paper considers extensions to algebraic modelling languages to support formulation, instantiation and solver integration for stochastic linear programs (SLPs). We present a taxonomy of SLP problem types and analyze formulation requirements including distribution handling by class of problem. We demonstrate suggested formulations for most problem classes, show solver input in the S-MPS standard, and propose consistency checks for constraints involving stochastic data items. Some unresolved difficulties are identified. 相似文献
92.
Single crystals of the orthoborate π-ErBO3 were synthesized from Er2O3 and B2O3 under high-pressure/high-temperature conditions of 2 GPa and 800 °C in a Walker-type multianvil apparatus. The crystal structure was determined on the basis of single-crystal X-ray diffraction data, collected at room temperature. The title compound crystallizes in the monoclinic pseudowollastonite-type structure, space group C2/c, with the lattice parameters a=1128.4(2) pm, b=652.6(2) pm, c=954.0(2) pm, and β=112.8(1)° (R1=0.0124 and wR2=0.0404 for all data). 相似文献
93.
R. Franchy G. Schmitz P. Gassmann F. Bartolucci 《Applied Physics A: Materials Science & Processing》1997,65(6):551-566
At 300 K, an amorphous Al-oxide film is formed on NiAl(001) upon oxygen adsorption. Annealing of the oxygen-saturated NiAl(001)
surface to 1200 K leads to the formation of thin well-ordered θ-Al2O3 films. At 300 K, and low-exposure oxygen atoms are chemisorbed on CoGa(001) on defects and on step edges of the terraces.
For higher exposure up to saturation, the adsorption of oxygen leads to the formation of an amorphous Ga-oxide film. The EEL
spectrum of the amorphous film exhibits two losses at ≈400 and 690 cm-1. After annealing the amorphous Ga-oxide films to 550 K thin, well-ordered β-Ga2O3 films are formed on top of the CoGa(001) surface. The EEL spectrum of the β-Ga2O3 films show strong Fuchs-Kliewer (FK) modes at 305, 455, 645, and 785 cm-1. The β-Ga2O3 films are well ordered and show (2×1) LEED pattern with two domains, oriented perpendicular to each other. The STM study
confirms the two domains structure and allows the determination of the two-dimensional lattice parameters of β-Ga2O3. The vibrational properties and the structure of β-Ga2O3 on CoGa(001) and θ-Al2O3 on NiAl(001) are very similar.
Ammonia adsorption at 80 K on NiAl(111) and NiAl(001) and subsequent thermal decomposition at elevated temperatures leads
to the formation of AlN. Well-ordered and homogeneous AlN thin films can be prepared by several cycles of ammonia adsorption
and annealing to 1250 K. The films render a distinct LEED pattern with hexagonal [AlN/NiAl(111)] or pseudo-twelve-fold [AlN/NiAl(001)]
symmetry. The lattice constant of the grown AlN film is determined to be aAlN= 3.11 Å. EEL spectra of AlN films show a FK phonon at 865 cm-1. The electronic gap is determined to be Eg= 6.1±0.2 eV. GaN films are prepared by using the same procedure on the (001) and (111) surfaces of CoGa. The films are characterized
by a FK phonon at 695 cm-1 and an electronic band gap Eg= 3.5±0.2 eV.
NO adsorption at 75 K on NiAl(001) and subsequent annealing to 1200 K leads to the formation of aluminium oxynitride (AlON).
An oxygen to nitrogen atomic ratio of ≈2:1 was estimated from the analysis of AES spectra. The AlON films shows a distinct
(2×1) LEED pattern and the EEL spectrum exhibits characteristic Fuchs-Kliewer modes. The energy gap is determined to be Eg= 6.6±0.2 eV. The structure of the AlON film is derived from that of θ-Al2O3 formed on NiAl(001).
Received: 21 March 1997/Accepted: 12 August 1997 相似文献
94.
Patricia Murasecco-Suardi Ernst Gassmann Andr M. Braun Esther Oliveros 《Helvetica chimica acta》1987,70(7):1760-1773
The quantum yield of intersystem crossing (Φisc) of a sensitizer is related to the quantum yield of singlet-oxygen production (Φ(1O2)) by the efficiency of the energy transfer (φet) and is an important parameter in the evaluation of potential applications of sensitized photo-oxidations. Using two different laser photolysis techniques, the energy-transfer method and the partial saturation method, Φisc of rose bengal has been determined in MeOH and in aqueous solutions. The results confirm that with Φisc(H2O) = 1.05(± 0.06) and Φisc(MeOH)=0.90(±0.08), the generally assumed relation Φisc · φet = Φ(1O2), with φet = 1, cannot be maintained any longer (Φ(1O2, H2O) = 0.75 and Φ(1O2, MeOH) = 0.76). During these experiments, a second intermediate has been observed which is produced from the triplet state of rose bengal and, stabilized in a anionic micellar solution, has been shown to be the radical cation of the sensitizer. The efficiency of the electron transfer has been evaluated from transient absorption and bleaching recordings, and it seems conclusive to attribute the results to the difference between Φisc and Φ(1O2). 相似文献
95.
Information
Congresses, conferences, symposia, consultations, and seminars in the field of chemical sciences held with participation of the russian academy of sciencesVI International Frumkin Symposium Fundamental Aspects of Electrochemistry* 相似文献96.
Wolfgang Dölling Almut Vogt Manfred Augustin 《Monatshefte für Chemie / Chemical Monthly》1989,120(10):879-889
Summary CH-Acidic O-alkyl dithiocarbonates1 react with carbon disulfide in a one-pot synthesis under basic conditions (NaH inDMF or phase transfer conditions) and S-alkylation to novel 1,3-dithiole-2-thiones3–6. The structure of these compounds and supporting n.m.r., ir and mass spectra are discussed. 相似文献
97.
98.
An XML-based schema for stochastic programs 总被引:1,自引:0,他引:1
This paper describes a proposed format to record instances of stochastic programs. It forms part of a larger XML-based schema
that is designed to allow the expression of essentially any type of mathematical program within a unifying framework. A wide
variety of different linear and nonlinear stochastic programs can be handled, and the paper describes in some detail how this
is done. Screen captures and sample problems illustrate the use of the schema. 相似文献
99.
100.
H. Gassmann 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1970,21(4):663-663
Ohne Zusammenfassung 相似文献