Quantum Noise Limits for Nonlinear, Phase-Invariant Amplifiers

Any quantum device that amplifies coherent states of a field while preserving their phase generates noise. A nonlinear, phase-invariant amplifier may generate less noise, over a range of input field strengths, than any linear amplifier with the same amplification. We present explicit examples of such nonlinear amplifiers, and derive lower bounds on the noise generated by a nonlinear, phase-invariant quantum amplifier.Comment: RevTeX, 6 pages + 4 figures (included in file; hard copy sent on request

“Green” Quantum Dots: Basics, Green Synthesis, and Nanotechnological Applications

Nanotechnological development of new materials involves the discovery or design of materials at small length scales with controlled physical and chemical properties than can be tuned or modified in function of their applications. One of the most suitable examples of nanoparticles used for this purpose are quantum dots, a type of colloidal fluorescent semiconducting nanocrystalline material that has the possibility, due to its unique optical and electronic properties, to be used in numerous technological applications such as biosensing, in vivo imaging techniques, photovoltaics, nanomedicine, molecular pathology, and drug delivery. Thus, there are almost endless possibilities for quantum dots materials. In spite of the fast advance in the search of quantum dots with better nanomaterial performance, environmentally benign and sustainable production is still lacking. Although the use of these materials is developing promptly, there is increasing concern that these materials might pose potential risks to human health. Herein, we discuss principal properties of quantum dots, including their functional architecture and toxicity, and review the main studies about “green” quantum dots synthesis to be aligned with green nanotechnology approach for nontoxic, cleaner, safer, and more responsible processes. The organometallic colloidal synthesis and the aqueous colloidal synthesis, as well as their drawbacks and benefits, are conferred. Recent advances in technological and biological quantum dots–based applications are also discussed in this chapter

Possibility to study eta-mesic nuclei and photoproduction of slow eta-mesons at the GRAAL facility

A new experiment is proposed with the aim to study eta-mesic nuclei and low-energy interactions of eta with nuclei. Two decay modes of eta produced by a photon beam inside a nucleus will be observed, namely a collisional decay \eta N \to \pi N inside the nucleus and the radiative decay \eta \to \gamma \gamma outside. In addition, a collisional decay of stopped S_{11}(1535) resonance inside the nucleus, S_{11}(1535) N \to N N, will be studied. The experiment can be performed using the tagged photon beam at ESRF with the end-point energy 1000 MeV and the GRAAL detector which includes a high-resolution BGO calorimeter and a large acceptance lead-scintillator time-of-flight wall. Some results of simulation and estimates of yields are given.Comment: 20 pages, 19 figure

RESEARCH ALGORITHM FOR BUSINESS ENTERPRISE ORGANIZATIONAL SUSTAINABILITY INDICES

Abstract. It is recommended that organizational sustainability of a business enterprise be assessed on the basis of a system of indices brought down in the article to characterize to what extent an option of the company organizational structure contributes to gaining higher final activity results. The indices may be used as efficiency criteria for options of the company organizational structure and management system. It is reasonable to assess each index from the viewpoint of its impact on the business company organizational and economic sustainability and to try either to eliminate the negative impact or to strengthen the positive role with respect of this sustainability

A Rational Approach to the Ecological Transition in the Cruise Market: Technologies and Design Compromises for the Fuel Switch

Supporting policies to achieve a green revolution and ecological transition is a global trend. Although the maritime transport of goods and people can rightly be counted among the least polluting sectors, much can be done to further reduce its environmental footprint. Moreover, to boost the ecological transition of vessels, a whole series of international regulations and national laws have been promulgated. Among these, the most impactful on both design and operational management of ships concern the containment of air-polluting emissions in terms of GHG, NOx, SOx and PM. To address this challenge, it might seem that many technologies already successfully used in other transport sectors could be applied. However, the peculiar characteristics of ships make this statement not entirely true. In fact, technological solutions recently adopted, for example, in the automotive sector must deal with the large size of vessels and the consequent large amount of energy necessary for their operation. In this paper, with reference to the case study of a medium/large-sized passenger cruise ship, the use of different fuels (LNG, ammonia, hydrogen) and technologies (internal combustion engines, fuel cells) for propulsion and energy generation on board will be compared. By imposing the design constraint of not modifying the payload and the speed of the ship, the criticalities linked to the use of one fuel rather than another will be highlighted. The current limits of application of some fuels will be made evident, with reference to the state of maturity of the relevant technologies. Furthermore, the operational consequences in terms of autonomy reduction will be presented. The obtained results underline the necessity for shipowners and shipbuilders to reflect on the compromises required by the challenges of the ecological transition, which will force them to choose between reducing payload or reducing performance

Half-Periodic Josephson Effect in an s-Wave Superconductor - Normal Metal -d-Wave Superconductor Junction

We predict that the Josephson current in a clean s-wave superconductor-normal metal-d-wave superconductor junction is periodic in superconducting phase difference $\phi$ with period $\pi$ instead of $2\pi$. The frequency of non-stationary Josephson effect is correspondingly $2\omega_J = 4eV.$ The effect is due to coexistence in the normal layer of current carrying Andreev levels with phase differences $\phi$ and $\phi+\pi.$Comment: 4 pages, REVTeX, 3 figure

Report on Chemical Analysis and Further Dating of Dinosaur Bones and Dinosaur Petroglypths

Much of the material in this report was presented at the 1990 ICC poster sessions. Our radiocarbon dates of dinosaur bones and the other information in this report should be alarming to the evolutionary community and should be given serious study considering our preliminary results

АЛГОРИТМ ИССЛЕДОВАНИЯ ПОКАЗАТЕЛЕЙ ОРГАНИЗАЦИОННОЙ УСТОЙЧИВОСТИ ПРЕДПРИНИМАТЕЛЬСКИХ СТРУКТУР

Abstract. It is recommended that organizational sustainability of a business enterprise be assessed on the basis of a system of indices brought down in the article to characterize to what extent an option of the company organizational structure contributes to gaining higher final activity results. The indices may be used as efficiency criteria for options of the company organizational structure and management system. It is reasonable to assess each index from the viewpoint of its impact on the business company organizational and economic sustainability and to try either to eliminate the negative impact or to strengthen the positive role with respect of this sustainability.Анализ организационной устойчивости предпринимательских структур предлагается осуществлять на основе системы приведенных в статье оценочных показателей, характеризующих, насколько вариант организационной структуры предприятия способствует достижению высоких конечных результатов деятельности. Показатели можно использовать в качестве критериев эффективности организационных структур и систем управления предприятиями. Каждый из приведенных показателей целесообразно рассматривать с позиции либо устранения его негативного воздействия на организационно-экономическую устойчивость предпринимательской структуры, либо усиления его роли в повышении этой устойчивости