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The article describes the commissioning and technical development of the Weak Interaction Studies with 32Ar Decay (WISArD) experiment, installed at the radioactive ion-beam facility ISOLDE/CERN. The experiment aims to extend the present limits on scalar and tensor currents in the weak interaction and hence search for physics beyond the Standard Model. The evaluation of these limits relies on measuring the proton energy in beta-delayed proton emission, sensitive to both the beta-neutrino angular correlation coefficient aβν and the Fierz interference term b. The method tries to improve previous studies by considering the positron-proton coincidences when determining the kinematic shift in the energy of the emitted protons. Using this coincidence technique, the aβν and b coefficients will be measured at the per mil level. Simulations were employed to optimize the ion beam transport efficiency and validate proof-of-principle results obtained in November 2018 (Nov2018). Upgrades are ongoing, and we are looking into improvements to the overall performance of the setup.

The processes and systems of production and training, influenced by the digital era, are forced to evolve at an accelerated pace to satisfy the need of innovation and digitization. Thus, the development of virtual learning factories within universities, which can adapt to the requirements of innovation and digitalization, is a solution. In this context, the paper presents how to development a virtual learning factory, flexible-reconfigurable to allow easier learning and experimentation of methods, techniques and tools used in Lean manufacturing. To achieve this, specific Lean manufacturing methods will be digitized for integration into the virtual factory, through programming in the Unity platform, using its specific C # language. Thus, at the end of the paper we want to obtain a virtual, mobile and flexible learning factory, which will help the user to understand, learn and experiment easily and in an attractive way the methods and techniques used in Lean manufacturing.

The need for automation and digitization has led to a rapid evolution of internal logistics processes and systems. This paper presents the automation mode logistics activities in an assembly line, by integrating a robotic arm. For the integration of the robotic arm, several steps are followed, consisting in designing the assembly line and the robotic arm using the Process Simulate software, simulating the operation of the line for different scenarios for integrating the robotic arm and analysing them. The study is completed with the realization in the laboratory of the assembly line with automated logistics activities. At the end of the project, it is desired to use the automated assembly line in the university environment, for the formation of students' competencies in the field of use of digital techniques and industrial logistics.

In the last period, logistics knew a strong technological evolution that has changed the way it operates and determined its transformation into innovative logistics, especially in the case of internal logistics. Innovation in internal logistics processes and systems consists in the use of different Industry 4.0 and digitization technologies. So, it is necessary to use modern methods and techniques to support the transformation of internal logistics processes and systems into innovative ones. This paper presents an analysis of recent studies, briefly presenting the evolution of the concept of logistics, the concepts of process and logistics system and Industry 4.0. Also, the most common methods and techniques used in the realization of innovative internal logistics systems are presented and some conclusions are presented regarding their use.

The rapid evolution of science and technology has forced the processes and systems of production, training and learning to adapt to innovation and the digital era of industrial technology. In the case of production processes and systems, innovation and digitalization refer to the transformation of production units into smart factories. In the case of training and learning processes and systems, innovation and digitalization lead to the creation of learning factories. Thus, this process involves the use of modern methods and techniques to develop innovative training, learning and production processes and systems. This paper is an analysis of recent studies and seeks to briefly present the evolution of industrial production processes and systems and Industry 4.0 but also the concept of learning factory. The paper also presents a review of the main methods and techniques used in innovative industrial training, learning and production processes and systems. Finally, some conclusions related to the use of these methods and techniques are summarized.

Few cycle pulse damage of ultra-broad band chirped mirror was studied with 5 fs pulses showing dramatic damage morphology, which has been analyzed with cross-sectional scanning electron microscopy, showing delamination behavior of the top few layers.

Laser-induced damage mechanisms were investigated for an ultra-broadband chirped mirror, as part of a systematic study of few-cycle pulse laser-induced damage threshold (LIDT) of widely-used ultra-broadband optics, in vacuum and in air, for single and multi-pulse regimes (S-on-1). Microscopic analysis of damage morphology suggests that three different damage mechanisms occur across the fluence range 0.15-0.4J/cm2, while no ablation was yet observed. The three regimes resulted in shallow swelling (< 10 nm tall), tall blistering (~ 150 nm tall), and annular blistering (damage suppressed at highest intensity, forming a ring shape). Descriptions of the potential mechanisms are discussed.

A compact system for the generation of few-cycle multi-mJ Carrier Envelope Phase (CEP) stabilized pulses is presented. At the output 1.9 mJ, 5.7 fs pulses were achieved after hollow fiber compression (HFC) of 5 mJ, 25 fs circularly-polarized pulses from a Ti:sapphire multipass chirped pulse amplifier (CPA). Polarization control of the generated pulses was done using all reflective phase retarders which can be nearly arbitrarily scaled for increasing energies. The CEP noise from the amplifier system is shown to be 190 mrad rms over a period of more than 7 hours. The full system, i.e., oscillator, amplifier, CEP stabilization, and HFC is compact enough to fit on a standard optical table.

Conventional phonon Raman spectroscopy is a powerful experimental technique for the study of crystalline solids that allows crystallography, phase and domain identification on length scales down to approximately 1 microm. Here we demonstrate the extension of tip-enhanced Raman spectroscopy to optical crystallography on the nanoscale by identifying intrinsic ferroelectric domains of individual BaTiO(3) nanocrystals through selective probing of different transverse optical phonon modes in the system. The technique is generally applicable for most crystal classes, and for example, structural inhomogeneities, phase transitions, ferroic order and related finite-size effects occurring on nanometre length scales can be studied with simultaneous symmetry selectivity, nanoscale sensitivity and chemical specificity.

Through our researches were carried out at ICDCOC- Palas, Constantza, we proposed ourselves to establish the poly-parasitism structure on sheep, as well as elaborating efficientical methods for anti-parasitical prophylaxis and fighting in sheep populations and pasture sourfaces, in order to ensuring anti-parasitical protection in sheep exploitations The copro-parasitological examinations was carried ovoscopicaly (flotation - by Willis and Mc. Master methods; sediment – by polyvalent method) and larvoscopicaly – by Baermann method). The parasitological examination of coprological smears which were harvested on sheep showed the presence of polyparasitism phenomenon with protozoans (coccidiae: Eimeria spp.) and helmints (cestodae: Moniesia expansa; gastro-intestinal nemathodes: Trichostrongylus spp., Nematodirus spp., Strongyloides papillosus and pulmonary nemathodes: Müellerius capillaris, Protostrongylus rufescens, Dictyocaulus filaria. Also, we proposed ourselves to study the paresites and their intermediary stages on pastures which were exploited with sheep, comparatively with mowed pastures. In the ansamble of research activities a special place is occupied by testing differents methods, in order to prevention and fighting of parasitical infestations on sheep and pasture in sheep farms.

Thin film properties of the set of metal-free linearly benzo-annelated porphyrazines, tetra(tert-butyl)porphyrazine (tBu-TAPH2), tetra(tert-butyl)phthalocyanine (tBu-PcH2), tetra(tert-butyl)naphthalocyanine (tBu-NpH2), and octaphenyltetraanthraporphyrazine (AnH2) were studied by laser excitation using micro-Raman and -luminescence spectroscopy. With the exception of tBu-TAPH2 all compounds are characterized by a broad absorption pattern mainly due to excitonic coupling. A strong bathochromic energy shift for the Q-band absorption per annelated benzo-moiety was found in solution as well as in the solid state in going from tBu-TAPH2 to AnH2. Films of tBu-TAPH2, tBu-PcH2, and tBu-NpH2 exhibit a single broad featureless luminescence band with a large Stokes shift, which originates from an excitonic state. In addition, tBu-TAPH2 and tBu-NpH2 exhibit photoluminescence peaks emerging from monomer-like molecules. These porphyrazines are the only ones known to show two luminescence peaks each. A systematic decrease in luminescence efficiency of thin films is observed and can be attributed to exciton coupling and migration leading to efficient quenching of the radiative decay channels. It also allows for Raman spectroscopic characterization of the thin films and for the case of tBu-NpH2 in highly concentrated solutions.The different resonance Raman spectra of the compounds can be used as fingerprint for distinguishing the degree of benzo-annelation.

The fundamental mechanisms of tip-enhanced Raman spectroscopy (TERS) have been investigated, including the role of the plasmonic excitation of the metallic tips, the nature of the optical tip–sample coupling, and the resulting local-field enhancement and confinement responsible for ultrahigh resolution imaging down to just several nanometers. Criteria for the distinction of near-field signature from far-field imaging artifacts are addressed. TERS results of molecules are presented. With enhancement factors as high as 109, single-molecule spectroscopy is demonstrated. Spatially resolved vibrational mapping of crystalline nanostructures and determination of crystallographic orientation and domains is discussed making use of the symmetry properties of the tip scattering response and the intrinsic Raman selection rules.

In this paper we present a precise and reliable measurement of the 1s(2)2p P-2(3/2) lifetime for Li-like Ni. The measurement was done using the technique of beam-foil spectroscopy employing a beam of 5.9 MeV/u Ni from the UNILAC accelerator at GSI. Special attention was taken concerning satellite blending and foil-ageing problems to justify the reliability of the lifetime value extracted from the measured decay curve. The experimental value for the 2p P-2(3/2) lifetime, 0.168 +/- 0.006 ns, is found to be in very good agreement with theoretical results.

Linear light scattering by individual nanoscopic metal wire tips is investigated. Using evanescent-wave exci- tation, the spectral and polarization dependence of the emis- sion are addressed. Choosing gold and tungsten as represen- tative tip materials, intense scattering and a strongly plasmon- resonant behavior observed for gold contrasts a comparatively weak and spectrally flat response for tungsten. Spectral depen- dence and local-field enhancement are found to be sensitive to details of the structural parameters and can be described by a simple model. The results provide selection criteria for tips to be used in scattering-type near-field microscopy or for photoemission in inelastic tunneling spectroscopy.

Using adjustable speed drives employing fast switching components to supply low voltage asynchronous motors may be detrimental to their reliability in some cases. The premature failures of the insulating materials are often attributed to the existence of partial discharges (PD) in the windings. Nevertheless, a clear evidence of any PD existence in such systems is far from being established. Also, their location may not be in the turn-to-ground or phase-to-phase insulation but in the turn-to-turn insulation due to the voltage waveforms, and as such, the classical AC test is no longer applicable. The aim of this paper is to present an off-line test procedure capable of overcoming this problem. The results of the test carried out on the representative population of different motors are presented.

The implementation of multilayer optics for the compression and delivery of few-cycle femtosecond pulses will be discussed in the case of several cutting-edge applications.

A model of SU(2) gauge theory in the space-time $R\times S^3$ is constructed in terms of local gauge-invariant variables. A metric tensor $g_{\mu \nu}$ is defined starting with the components of the strength tensor $F_{\mu \nu}^k$ and of its dual $\widetilde{F}_{\mu \nu}^k$. It is shown that the components $g_{\mu \nu}$ determine the gauge field equations if some supplementary constraints are imposed. Two families of analitical solutions of the field equations are also obtained.

A systematic study of few-cycle pulse laser induced damage threshold (LIDT) determination was performed for commercially-available ultra-broadband optics, (i.e. chirped mirrors, silver mirrors, beamsplitters, etc.) in vacuum and in air, for single and multi-pulse regime (S-on-1). Multi-pulse damage morphology at fluences below the single-pulse LIDT was studied in order to investigate the mechanisms leading to the onset of damage. Stark morphological contrast was observed between multi-pulse damage sites formed in air versus those in vacuum. One effect of vacuum testing compared to air included suppression of laser-induced periodic surface structures (LIPSS) formation, possibly influenced by a reduced presence of damage debris. Another effect of vacuum was occasional lowering of LIDT, which appears to be due to the stress-strain performance of the coating design during laser irradiation and under the external stress of vacuum ambience. A fused silica substrate is also examined, and a non-LIPSS nanostructuring is observed on the surface. Possible mechanisms are discussed.

A compact system for the generation of few-cycle multi-mJ carrier envelope phase (CEP) stabilized pulses is presented. The output 5.4 fs, 1.9 mJ pulses have CEP noise of only 190 mrad rms over seven hours.

Focusing light to subwavelength dimensions has been a long-standing desire in optics but has remained challenging, even with new strategies based on near-field effects, polaritons, and metamaterials. The adiabatic propagation of surface plasmon polaritons (SPP) on a conical taper as proposed theoretically has recently emerged as particularly promising to obtain a nanoconfined light source at the tip. Employing grating-coupling of SPPs onto gold tips, we demonstrate plasmonic nanofocusing into a localized excitation of approximately 20 nm in size and investigate its near- and far-field behavior. For cone angles of approximately 10-20 degrees , the breakdown of the adiabatic propagation conditions is found to be localized at or near the apex region with approximately 10 nm radius. Despite an asymmetric side-on SPP excitation, the apex far-field emission with axial polarization characteristics representing a radially symmetric SPP mode in the nanofocus confirms that the conical tip acts as an effective mode filter with only the fundamental radially symmetric TM mode (m = 0) propagating to the apex. We demonstrate the use of these tips as a source for nearly background-free scattering-type scanning near-field optical microscopy (s-SNOM).

Optical-field enhancement and confinement for an asymmetrically illuminated nanoscopic Au tip suspended over a planar Au substrate is investigated both numerically and experimentally. The spatial field distribution of the tip-sample system was calculated using the full 3D finite-difference time-domain method. The calculation enables investigation of the effects of the substrate-tip placement, angle of incidence, and spectral response. The tip plasmon response leads to a significant (up to ~70 times) local field enhancement between the tip and substrate. The enhancement is found to be extremely sensitive to the tip-sample separation distance. Tip-enhanced Raman scattering experiments were performed and the numerical results provide a consistent description of the observed field localization and enhancement.

Near-field tip-enhanced and symmetry-selective nonlinear light scattering is demonstrated for imaging nanoscopic ferroelectric order. The surface topology of antiparallel ferroelectric domains in multiferroic ${\text{YMnO}}_{3}$ is spatially resolved by second-harmonic generation (SHG). Optical phase contrast is obtained by interference between the local near-field SHG and a self-homodyne far-field reference SHG field. Ferroelectric domains anisotropically elongated along the hexagonal crystallographic axis were found, with typical dimensions of $\ensuremath{\sim}1000\ifmmode\times\else\texttimes\fi{}200\text{ }{\text{nm}}^{2}$. The irregular domain shapes seem to contrast the behavior of ordinary ferroelectrics. Relying on symmetry properties only, SHG scattering-type scanning near-field optical microscopy can be extended to probe any ferroic order.

Flat and nanostructured metal nano-tips driven by sub-10 fs pulses at an 80-MHz repetition rate serve for nano-confined light and electron generation. We demonstrate control of spatial emission properties and analyze nonlinear generation processes.

We describe and demonstrate a new nanometer-scale broadband light source. It is based on the grating-coupled excitation of surface plasmon polaritons (SPPs) on the shaft of a sharp conical metal taper with a tip radius of few tens of nanometers. Far-field excitation of linear nanoslit gratings results in the resonant generation of SPPs traveling over more than 10 mum to the tip apex and converging to an intense radiative local light spot. Such nanofabricated tips are expected to find various applications in nanospectroscopy, overcoming problems with background illumination in apertureless microscopy.

In the Comment by Domke and Pettinger [Phys. Rev. B 75, 236401 (2007)] on our study on ``Scanning-probe Raman spectroscopy with single-molecule sensitivity'' [C. C. Neacsu et al. Phys. Rev. B 73, 193406 (2006)] the authors raise concerns whether our tip-enhanced Raman response is due to carbon clusters as molecular decomposition products of the malachite green molecules used. Their arguments are based on the different spectral characteristics we observe between the tip-enhanced and far-field Raman response. Here, we show the results of systematic control experiments to support the conclusions drawn by Neacsu et al. that all spectral features can be related to malachite green molecules. Comparing Raman spectra for different degrees of near-field enhancement, the absence of spectral changes during bleaching, examining a broad spectral range, and the explicit comparison with Raman signals from carbon impurities validates our original assignment, including the single-molecule response.

Single-molecule vibrational Raman spectroscopy of malachite green adsorbed on planar metal surfaces is achieved by means of optical local-field enhancement provided by a scanning nanoscopic metallic tip. The single-molecule signature is evident from spectral diffusion and a discretization of Raman peak intensities. The optical tip-sample coupling gives rise to a localization of the response down to a sub-$10\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$ length scale and a Raman enhancement up to $\ensuremath{\sim}5\ifmmode\times\else\texttimes\fi{}{10}^{9}$. This combines vibrational spectroscopy with high resolution scanning-probe microscopy for ultrasensitive in situ analysis of individual molecules.

Second-harmonic generation sSHGd from individual nanoscopic metal tips has been investigated. Compared to both planar interfaces, as well as spherical or ellipsoidal nanoparticles, very different polarization selection rules and SH-emission directions result. As a partially asymmetric nanostructure the tip allows for the distinction of otherwise inseparable local surface and nonlocal bulk second-harmonic polarizations. This provides opportunities for second-harmonic investigations of nanoparticles and in scattering-type near field microscopy. The optics of media of dimensions small compared to the optical wavelength is characterized by distinctive phenomena such as optical field confinement and structural resonances. With a strong focus in research on the linear optical processes of surface nanostructures and colloids, the nonlinear optical properties have remained largely unexplored. The nonlinear response, however, is expected to differ fundamentally due to its high symmetry selectivity. Specifically, for media with inversion symmetry the second-order nonlinearity is dominated by the interface where the symmetry is broken. 1 Second-harmonic generation sSHGd has thus become a well-established technique for the investigation of planar surfaces and interfaces. 2 Many applications, however, would call for an expansion of SHG to also address molecular adsorption and surface electronic and geometric structure on the nanoscale. Here, the problem of SHG becomes particularly intriguing: Although at the surface of the nanostructure the inversion symmetry is broken locally, depending on its dimension and macroscopic symmetry, emission can be highly restricted due to the destructive interference of the induced local surface second-harmonic sSHd polarizations. 3,4 In this paper we address the different contributions to the nonlinear source polarization and provide general directional and polarization selection rules for second-harmonic generation from partially asymmetric smmd nanostructures. Metal wire tips with a nanometer-sized apex represent a model geometry, with the mirror symmetry being broken along the tip axis but conserved in all other directions. This structure allows for the direct separation between local surface and nonlocal higher-order bulk contributions to the SH response—a

The paper investigates a new multi-tone harmonic balance approach based on multivariate representation of multirate signals. The proposed algorithm generates the new Newton-Raphson iterate using an iterative method based on Krylov subspaces - namely the GMRES method. An example of using the simulator developed around the proposed method is finally shown.

This paper presents a way of implementing the MOST channels' Noise Current Cancellation Technique (NCCT) on a mixer for reducing its noise figure, generating a new mixer architecture designed in a 0.18mm RF CMOS UMC technology. The MOST Channel's Noise Current Cancellation Technique was first time presented. The noise figure performance of the new mixer architecture can be as low as 4.4dB@80MHz or if coils are used 1dB@80MHz noise figure can be reached. The conversion gain of such a mixer is higher than 20dB, the IP3 is -5dBm and the power consumption are smaller than 18mW at 1.8V power supply. All simulations for the new mixer architecture were made with SpectreRF.

Using adjustable speed drives employing fast switching components, to supply low voltage asynchronous motors may, in some cases, be detrimental to their reliability. The premature failures of the insulating materials are often attributed to the existence of partial discharges (PD) in the winding. Nevertheless, a clear evidence of PD existence in such systems is far from being established. Due to the voltage waveforms, their location is not in the turn-to-ground or phase-to-phase insulation but in the turn-to-turn insulation and the classical AC test is no longer applicable. The aim of this paper is to present an off line test procedure and its results able to solve this problem.

Premature failures of low voltage rotating machines fed by inverters are often attributed to the existence of Partial Discharges (PD). Nevertheless, a clear and direct evidence of PD existence in such systems is far from being established. Since their location is not in the turn to ground or phase to phase insulating materials, classical ac tests are not applicable. We present in the following an off line test able to solve this problem.

Using rather simple and mild extraction and separation methods, three ovine pineal fractions (XM 300 R-PP7.2' and PP7.2 S) were obtained, which contain peptidic/proteic substances and which show fluorescence characteristics of indoles. The ovine fractions were compared with the bovine pineal E-5 fraction. The ovine fractions are chemically sensitive to normal laboratory light and stable in red light (lambda greater than 600 nm). Immunologically, these fractions and the bovine E 5 fraction are stable. From the results of radioimmunological experiments it was concluded that the bovine pineal E 5 fraction as well as the ovine pineal fraction XM 300 R-PP7.2 and PP7.2S may contain (a) peptide(s) ending by the same carboxy terminal tripeptide Pro-Arg-Gly(NH2).

Peptides with vasopressin- and oxytocin-immunoreactivity were purified from bovine pineal glands. Three immunoreactive peptides were purified by successive high performance liquid chromatography steps in sufficient quantities for identification by fast atom bombardment-mass spectrometry. Two peptides were characterized as authentic vasopressin and oxytocin. Their identities were in agreement with the observed immunoreactivities, high performance liquid chromatography behavior, and biological activity. The third peptide was identified as N alpha-acetyloxytocin. The presence of the acetyl group was demonstrated by the molecular mass of the peptide, and the N alpha position was shown to be the modified site by the presence of a blocked NH2 terminus. N alpha-Acetylation of oxytocin may be involved in altering the biological properties of the peptide.

A polypeptide with pressor and oxytocic activities has been isolated from bovine pineal gland. This polypeptide is neither arginine—or lysine—vasopressin, nor oxytocin. The biological and chromatographic characteristics are similar to those of arginine vasotocin. It is concluded that the pineal polypeptide is arginine vasotocin or a hormone with similar structure.

The vasotocin-like biological activity detected in an extract (E5 fraction) of bovine pineal gland was found not to be due to the presence of vasotocin, vasopressin or oxytocin. The data obtained by means of bio- and radio-immunoassays suggest that the peptide responsible for this biological activity, however, possesses the same Pro-Arg-Gly(NH2) tripeptidic carboxy-terminal end as vasotocin.

Peptides with vasopressin- and oxytocin-immunoreactivity were purified from bovine pineal glands. Three immunoreactive peptides were purified by successive high performance liquid chromatography steps in sufficient quantities for identification by fast atom bombardment-mass spectrometry. Two peptides were characterized as authentic vasopressin and oxytocin. Their identities were in agreement with the observed immunoreactivities, high performance liquid chromatography behavior, and biological activity. The third peptide was identified as N alpha-acetyloxytocin. The presence of the acetyl group was demonstrated by the molecular mass of the peptide, and the N alpha position was shown to be the modified site by the presence of a blocked NH2 terminus. N alpha-Acetylation of oxytocin may be involved in altering the biological properties of the peptide.

(1984). Cardiovascular Effects of the Hog Pineal E5 Peptide in Rats. Clinical and Experimental Hypertension. Part A: Theory and Practice: Vol. 6, No. 10-11, pp. 2091-2096.

RECENT investigations have shown that antigens stimulating the appearance of specific antibodies exist in the structure of the pig parathyroid1 and in crude or purified extracts of bovine parathyroid2–4; these antigens stimulate the occurrence of specific antibodies which exert an inhibiting action on the parathyroid hormone, thus influencing calcium metabolism.