The Reformatsky Reaction with Aliphatic Y- and b-Halonitriles. The Synthesis of Some 2-Substituted D 1 -Pyrrolines and D -1 -Piperideines

Starting from aliphatic y-orr: 11-halonitriles and a-bromoesters, w -halo-~-ketoesters, 2-substituted ~1 -pyrrolines or 2-substituted ~ 1-piperideines, were obtained. Some of the chemical and spectroscopic properties of the prepared compounds are described

Comparison of dynamic properties of InP/InAs quantum-dot and quantum-dash lasers

This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Appl. Phys. Lett. 109, 161104 (2016) and may be found at https://doi.org/10.1063/1.4965846.The dynamic properties of MOVPE grown InP/InAs quantum-dot and quantum-dash lasers, showing identical structural design, emitting in the C-band are investigated and compared to each other. Based on the small-signal measurements, we show the impact of the density of states function on the cut-off frequency, being larger for quantum dots at low currents, and reaching similar values for quantum dashes only at higher currents. The large-signal measurements show error-free data transmission at 22.5 and 17.5 Gbit/s for the quantum-dot and quantum-dash lasers.DFG, 43659573, SFB 787: Halbleiter - Nanophotonik: Materialien, Modelle, BauelementeEC/FP7/EU/264687/Postgraduate Research on Photonics as an Enabling Technology/PROPHE

Dynamical stability of the one-dimensional rigid Brownian rotator: The role of the rotator's spatial size and shape

We investigate dynamical stability of a single propeller-like shaped molecular cogwheel modelled as the fixed-axis rigid rotator. In the realistic situations, rotation of the finite-size cogwheel is subject of the envi- ronmentally-induced Brownian-motion effect that we describe by utilizing the quantum Caldeira-Leggett master equation, in the weak-coupling limit. Assuming the initially narrow (classical-like) standard deviations for the an- gle and the angular momentum of the rotator, we investigate dynamics of the first and second moments depending on the size, i.e., on the number of blades of both the free rotator as well as of the rotator in the external har- monic field. The larger the standard deviations, the less stable (i.e. less pre- dictable) rotation. We detect the absence of the simple and straightforward rules for utilizing the rotator's stability. Instead, a number of the size-related criteria appear whose combinations may provide the optimal rules for the ro- tator dynamical stability and possibly control. In the realistic situations, the quantum-mechanical corrections, albeit individually small, may effectively prove non-negligible, and also revealing subtlety of the transition from the quantum to the classical dynamics of the rotator. As to the latter, we detect a strong size-dependence of the transition to the classical dynamics beyond the quantum decoherence process.Comment: Corrections made in accordance to the Corrigendum to the published pape

Manifestation of the spin textures in the thermopower of MnSi

To identify possible spin texture contributions to thermoelectric transport, we present a detailed temperature and pressure dependence of thermopower $S$ in MnSi, as well as a low-temperature study of $S$ in a magnetic field. We find that $S/T$ reconstructs the $(p,T)$ phase diagram of MnSi encompassing the Fermi liquid, partially ordered, and non-Fermi liquid phases. Our results indicate that the latter two phases have essentially the same nature. In the partially ordered phase, $S(T)$ is strongly enhanced, which may be understood as a spiral-fluctuation-driven phase. A low temperature upturn in $S/T$ pertaining to the partial order phase persists up to the highest pressure, 24 kbar. Contrarily, a small suppression of $S(T)$ is observed in the ordered skyrmion lattice $A$ phase

Future Contingencies and the Arrow and Flow of Time in a Non-Deterministic World According to the Temporal-Modal System TM

It is shown how the temporal-modal system of events TM (axiomatized in Appendix) allows for the avoidance of the logical determinism without the rejection of the principle of bivalence. The point is that the temporal and the modal parts of TM are so inter-related that modalities are in-the-real-world-inherent modalities independently of whether they concern actual or only possible events. Though formulated in a tenseless language, whose interpretation does not require the assumption of tense facts at the basic level of reality, TM implies an objective, observer-independent difference between tenses based only on the way in which modalities are distributed along the time continuum. The conclusion is that the arrow of time is an intra-model characteristic of any model of TM that describes the non-deterministic real world up to a certain point of its history, while the flow of time is an inter-model characteristic of the continuous transition between these models

A General Method · for the Synthesis of Y- and d - Keto Esters

A method for th\u27e preparation of y- and 1-keto esters is described. The sodio derivative of 1,1-di-tert-butyl-2-ethylethanetricarboxylate or 1,1-di-tert-butyl-3-ethylpropanetricarboxylate is acylated with a carboxylic acid chloride. Elimination of tert-butyl groups and decarboxylation are accomplished by heating the acylated triester in toluene with a catalytic amount of p -toluenesulphonic acid. Under these conditions the carbethoxy group remains unattacked

1.55-μm mode-locked quantum-dot lasers with 300 MHz frequency tuning range

This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Appl. Phys. Lett. 106, 031114 (2015) and may be found at https://doi.org/10.1063/1.4906451.Passive mode-locking of two-section quantum-dot mode-locked lasers grown by metalorganic vapor phase epitaxy on InP is reported. 1250-μm long lasers exhibit a wide tuning range of 300 MHz around the fundamental mode-locking frequency of 33.48 GHz. The frequency tuning is achieved by varying the reverse bias of the saturable absorber from 0 to −2.2 V and the gain section current from 90 to 280 mA. 3 dB optical spectra width of 6–7 nm leads to ex-facet optical pulses with full-width half-maximum down to 3.7 ps. Single-section quantum-dot mode-locked lasers show 0.8 ps broad optical pulses after external fiber-based compression. Injection current tuning from 70 to 300 mA leads to 30 MHz frequency tuning.DFG, 43659573, SFB 787: Halbleiter - Nanophotonik: Materialien, Modelle, BauelementeEC/FP7/EU/264687/Postgraduate Research on Photonics as an Enabling Technology/PROPHE

Gender and number in the nominal domain : an introduction

In this introduction, we provide a general overview of the properties of gender and number, two nominal grammatical categories that this special issue is devoted to. Grammatical gender and number have been studied from a variety of theoretical viewpoints and still there is no commonly established and well-defined view on the nature of the two categories. The term 'gender' is used for a range of grammatical phenomena, including noun-classification into corresponding inflection classes and syntactically conditioned rules of agreement and concord. Like grammatical gender, grammatical number can be realized through inflection on the noun and/or through the agreement that it triggers on other items. However, unlike grammatical gender, grammatical number has stable, straightforward and systematic interpretive effects, related to the quantity of the predicate denoted by the noun, and hence also of the referent when the nominal expression is referential. Number and gender are core features of nouns and make up or participate in some of the hallmark properties of natural language.En aquesta introducció, fem un repàs general de les propietats del gènere i del nombre, les dues categories nominals de què s'ocupa aquest volum monogràfic. L'estudi del gènere i del nombre gramaticals s'ha abordat des de diverses perspectives teòriques i encara no hi ha una visió generalment acceptada i ben definida de la naturalesa d'aquestes dues categories. El terme gènere s'aplica a un ventall de fenòmens gramaticals que inclouen la classificació dels noms en classes flexives i les regles sintàctiques de concordança i acord. Com passa amb el gènere gramatical, el nombre gramatical es pot realitzar mitjançant la flexió del nom i/o la concordança que força en altres elements. No obstant això, a diferència del gènere gramatical, té efectes interpretatius estables, clars i sistemàtics, relacionats amb la quantitat del predicat que denota el nom, i, per tant, també del referent quan l'expressió nominal és referencial. El nombre i el gènere són trets fonamentals els noms i constitueixen algunes de les propietats definitòries del llenguatge natural o hi contribueixen

Highly efficient non-degenerate four-wave mixing under dual-mode injection in InP/InAs quantum-dash and quantum-dot lasers at 1.55 μm

This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Appl. Phys. Lett. 107, 191111 (2015) and may be found at https://doi.org/10.1063/1.4935796.This work reports on non-degenerate four-wave mixing under dual-mode injection in metalorganic vapor phase epitaxy grown InP/InAs quantum-dash and quantum dot Fabry-Perot laser operating at 1550 nm. High values of normalized conversion efficiency of −18.6 dB, optical signal-to-noise ratio of 37 dB, and third order optical susceptibility normalized to material gain χ(3)/g0 of ∼4 × 10−19 m3/V3 are measured for 1490 μm long quantum-dash lasers. These values are similar to those obtained with distributed-feedback lasers and semiconductor optical amplifiers, which are much more complicated to fabricate. On the other hand, due to the faster gain saturation and enhanced modulation of carrier populations, quantum-dot lasers demonstrate 12 dB lower conversion efficiency and 4 times lower χ(3)/g0 compared to quantum dash lasers.DFG, 43659573, SFB 787: Halbleiter - Nanophotonik: Materialien, Modelle, BauelementeEC/FP7/EU/264687/Postgraduate Research on Photonics as an Enabling Technology/PROPHE