Large melting point depression of 2–3‐nm length‐scale nanocrystals formed by the self‐assembly of an associative polymer: Telechelic,pyrene‐labeled poly(dimethylsiloxane)

Large melting point depressions for organic nanocrystals, in comparison with those of the bulk, were observed in an associative polymer: telechelic, pyrene‐labeled poly(dimethylsiloxane) (Py‐PDMS‐Py). Nanocrystals formed within nanoaggregates of pyrenyl units that were immiscible in poly(dimethylsiloxane). For 5 and 7 kg/mol Py‐PDMS‐Py, physical gels resulted, with melting points exceeding 40 °C and with small‐angle X‐ray scattering peaks indicating that the crystals were nanoconfined, were 2–3 nm long, and contained roughly 18–30 pyrenyl dye end units. In contrast, 30 kg/mol Py‐PDMS‐PY was not a gel and exhibited no scattering peak at room temperature; however, after 12 h of annealing at ?5 °C, multiple melting peaks were present at 5–30 °C. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 3470–3475, 2004     

Upon the removal of the edges of a 1-factor from an even circuit in a 2-connected graph

Let G be a 2-connected graph with minimum degree at least 3. We prove that there exists an even circuit C in G with factorization F={F₁,F₂} such that G−E(F₁) is 2-connected.     

Signals in chaos: A method for the cancellation of deterministic noise from discrete signals

In this paper we describe a method for separating a combination of a chaotic time series and a discrete-valued signal. The method uses a feedback technique stabilised using knowledge of the chaotic system and the discrete nature of the signal. It is not based on a linearization of the dynamics, and therefore, unlike previously proposed separation methods, does not require that the signal be small. Nor does it make any assumptions about the relative timescales of the signal and the chaotic time series.     

The Clock Paradox in a Static Homogeneous Gravitational Field1

The gedanken experiment of the clock paradox is solved exactly using the general relativistic equations for a static homogeneous gravitational field. We demonstrate that the general and special relativistic clock paradox solutions are identical and in particular that they are identical for finite acceleration. Practical expressions are obtained for proper time and coordinate time by using the destination distance as the key observable parameter. This solution provides a formal demonstration of the identity between the special and general relativistic clock paradox with finite acceleration and where proper time is assumed to be the same in both formalisms. By solving the equations of motion for a freely falling clock in a static homogeneous field elapsed times are calculated for realistic journeys to the stars. ¹ Both authors contributed equally to this paper.     

Nano-electrochemical detection of hydrogen or protons using palladium nanoparticles: distinguishing surface and bulk hydrogen.

The benefits of using nanoparticle-modified electrodes are exemplified through the electrochemical detection of protons and/or hydrogen. It is shown that a palladium-nanoparticle-modified boron-doped diamond allows voltammetric information relating to the relative roles played by the surface and the bulk metal to be obtained for the proton-hydrogen system at palladium surfaces which is not accessible using palladium macroelectrodes or microelectrodes.     

BELENE nuclear power plant numerical and experimental bedrock,layers and surface signals

An investigation of BELENE Nuclear Power Plant (NPP) free field signal is presented in the current study. An SH wave propagation trough multilayer geological media in the region is considered. An original structural model of the geological column has been developed. The investigated layers are isotropic, with constant depth and skyline parallel. The SH rays are with an arbitrary angle as far as the layers are concerned. The seismic SH waves have been generated by a special detonation device. The main results of the study are graphically illustrated. A comparison between the original BELENE NPP experimental and the numerical surface (free field) signals (obtained by the formulated direct problem) for the investigated geological column has been carried out and its results are hereby shown.     

Consequence for Wavefunction Collapse Model of the Sudbury Neutrino Observatory Experiment

It is shown that data on the dissociation rate of deuterium obtained in an experiment at the Sudbury Neutrino Observatory provides evidence that the Continuous Spontaneous Localization wavefunction collapse model should have mass–proportional coupling to be viable.     

Potent New Heterogeneous Asymmetric Catalysts

A set of new, air‐stable, Rh^I‐based heterogeneous asymmetric hydrogenation catalysts have been synthesised, characterised, and tested. Individual members of this new family all exhibit good enantioselectivity.