Realization of a Framework for Simulation-Based Large-Scale Shape Optimization Using Vertex Morphing

Journal of Optimization Theory and Applications - There is a significant tendency in the industry for automation of the engineering design process. This requires the capability of analyzing an...     

On total covers of graphs

A total cover of a graph G is a subset of V(G)E(G) which covers all elements of V(G)E(G). The total covering number ₂(G) of a graph G is the minimum cardinality of a total cover in G. In [1], it is proven that ₂(G)[n/2] for a connected graph G of order n. Here we consider the extremal case and give some properties of connected graphs which have a total covering number [n/2]. We prove that such a graph with even order has a 1-factor and such a graph with odd order is factor-critical.     

Umlagerungen von Heterocyclen,IX Mesoionische Sechsringheterocyclen,XV Ketenoide Umlagerungen mesoionischer Pyrimido [1,2-a]chinoline

Tricyclic pyrimidine betaines2, which are obtained from the reaction of 2-anilino quinolines (4) and 2,4,6-trichlorophenyl malonates (3) rearrange at temperatures above 200°Cvia ketene intermediates. Formation of either the ketene11 or the acylketene16 depends upon the reaction medium (2,4,6-trichlorophenol or diphenyl ether as solvent). The structures of the resulting rearranged products6 or7, resp., were established in the case of the pyrimido[3,4-a]quinoline7 by an independent synthesis, and for the 4-hydroxy-2-quinolone6 by degradation to the quinazolone19.     

Bonding corneal tissue: applications of photoactivated diazopyruvoyl cross-linking agent

Photoactivated bis-diazopyruvamide-N,N'-bis(3-diazopyruvoyl)-2,2'-(ethylenedioxy)bis-(ethylamine), (DPD)-was previously shown to bond materials containing type I collagen. However, tensile strength of bonded collagenous tissue ( approximately 78% water) was low compared with that of dehydrated collagenous gelatin ( approximately 14% water). Here we investigated the role of water in corneal tissue bond strength and in bonding corneal tissue to glass. Bonding corneal tissue to glass may be of value in surgically anchoring keratoprostheses to corneas to alleviate problems with extrusion. Bovine corneal samples were lyophilized for various times resulting in tissue hydrations of zero (no water content) to approximately 3.7 (normal water content). The lyophilized corneal tissue was bonded to solid gelatin sheets, to other corneal samples and to glass using 0.3M DPD in chloroform. Control runs used chloroform only. Samples were irradiated with 100 or 200 J of 320-500 nm light. Strong bonds formed with all three materials when corneal tissue hydration was 1. No bonding occurred with chloroform alone. Formation of strong bonds only occurs with hydration levels 相似文献   

A redetermination of the lifetime of the 4s 5s (3S1) level in Ca by high-rate electron—photon stepwise pulse excitation

The radiative lifetime of the 4s 5s (³S₁) level in Ca was measured using two-step excitation of atoms in a beam which traverses a cold-cathode Penning discharge, where, by electron impact the atoms are excited to the metastable 4s 5p (³P_{2, 1, 0}) states. Immediately thereafter, the beam is crossed with a pulse-modulated cw dye laser beam to populate the final state selectively. Using a pulse-modulation frequency of 0.5 MHz, a preliminary value of 12.4 ± 0.5 ns was obtained with a statistical error of 0.4%. The wide limits of systematic error reflect an assumed uncertainty in the excitation function and possible distortion in the fluorescence decay requiring further study.     

Preparation and IR-spectroscopic study of charge transfer complexes of naphthalene derivatives with some tri- and di-nitrobenzenes

The charge transfer complexes of naphthalene and some of its derivatives with some trinitro- and dinitrobenzenes are prepared and investigated by irspectroscopy. The shifts in the bands due to functional groups as well as the _CH bands of both donor and acceptor are found to be indicative for the type of bonding in the charge transfer complex.

---

Darstellung und IR-spektroskopische Untersuchungen an Charge Transfer Komplexen von Naphthalinderivaten mit Di- und Tri-nitrobenzolen

Zusammenfassung Aus den Verschiebungen der Bandenlagen bei der Komplexierung, bzw. aus der Abhängigkeit der Bandenlagen von den funktionellen Gruppen, wird der Bindungstyp der Charge-Transfer-Komplexe ermittelt.

     

Expected gain–loss pricing and hedging of contingent claims in incomplete markets by linear programming

We analyze the problem of pricing and hedging contingent claims in the multi-period, discrete time, discrete state case using the concept of a “λ gain–loss ratio opportunity”. Pricing results somewhat different from, but reminiscent of, the arbitrage pricing theorems of mathematical finance are obtained. Our analysis provides tighter price bounds on the contingent claim in an incomplete market, which may converge to a unique price for a specific value of a gain–loss preference parameter imposed by the market while the hedging policies may be different for different sides of the same trade. The results are obtained in the simpler framework of stochastic linear programming in a multi-period setting, and have the appealing feature of being very simple to derive and to articulate even for the non-specialist. They also extend to markets with transaction costs.     

Reusable Nano-Zirconia-Catalyzed Synthesis of Benzimidazoles and Their Antibacterial and Antifungal Activities

In this article, a zirconia-based nano-catalyst (Nano-ZrO₂), with intermolecular C-N bond formation for the synthesis of various benzimidazole-fused heterocycles in a concise method is reported. The robustness of this reaction is demonstrated by the synthesis of a series of benzimidazole drugs in a one-pot method. All synthesized materials were characterized using ¹HNMR, ¹³CNMR, and LC-MS spectroscopy as well as microanalysis data. Furthermore, the synthesis of nano-ZrO₂ was processed using a standard hydrothermal technique in pure form. The crystal structure of nano-ZrO₂ and phase purity were studied, and the crystallite size was calculated from XRD analysis using the Debye–Scherrer equation. Furthermore, the antimicrobial activity of the synthesized benzimidazole drugs was evaluated in terms of Gram-positive, Gram-negative, and antifungal activity, and the results were satisfactory.