TiO2 Nanostructures and Nanocomposites for Sustainable Photocatalytic Water Purification

Water, together with energy and food, has been addressed as one of the main urgent problems of humanity. The conventional wastewater treatments suffer some limitations related to the effectiveness in decontamination (mechanical filtration), in the heavy use of chemicals (chlorination), or in elevation of operational costs and energy requirements (desalination and reverse osmosis). In this sense, new materials such as nanocomposites may overcome these issues taking advantage of the peculiar properties of materials at nanoscale. Research on novel nanotechnologies must bring advances in order to contrast and prevent water scarcity and pollution. In order to be effective, these nanotechnologies should run at low operational cost, even in places unequipped by strong infrastructures and in concert with conventional cheap methodologies

PENERAPAN MODEL EXPLICIT INSTRUCTION PADA PEMBELAJARAN SENI TARI UNTUK MENINGKATKAN MINAT BELAJAR SISWA.

Judul penelitian ini adalah Penerapan Model Explicit Instruction Pada Pembelajaran Seni Tari Untuk Meningkatkan Minat Belajar Siswa (Studi Eksperimen Pada Siswa Kelas VIII-F SMP Negeri 3 Lembang). Permasalahan yang diangkat ialah bagaimana menumbuhkan minat belajar siswa melalui pembelajaran tari dengan tiga pertanyaan penelitian diantaranya, (1) Bagaimana minat belajar siswa terhadap pembelajaran seni tari sebelum diterapkannya model Explicit Instruction di kelas VIII-F SMP Negeri 3 Lembang?, (2) Bagaimana proses pembelajaran untuk meningkatkan minat belajar siswa terhadap pembelajaran seni tari melalui model Explicit Instruction di kelas VIII-F SMP Negeri 3 Lembang?, (3) Bagaimana hasil pembelajaran Seni Tari untuk meningkatkan minat belajar siswa setelah diterapkannya model Explicit Instruction dikelas VIII-F SMP Negeri 3 Lembang?. Metode penelitian yang digunakan adalah metode eksperimen pendekatan kuantitatif dan teknik pengumpulan data diantaranya studi pustaka, observasi, wawancara, tes, dan dokumentasi. Hasil analisis data dan temuan mengenai minat belajar siswa sebelum menggunakan model explicit instruction sangat rendah karena model pembelajaran yang digunakan belum tepat, peningkatan minat terlihat pada saat proses pembelajaran, kemudian uji t tabel yang menyatakan bahwa t_tes 4 > t_tab1,729. Hal ini membuktikan bahwa model explicit instruction sangat signifikan untuk meningkatkan minat belajar siswa dan dapat di jadikan sebagai salah satu rekomendasi untuk pembelajaran tari terutama dalam meningkatkan minat belajar siswa

Correction: Enhancing carrier generation in TiO2 by a synergistic effect between plasmon resonance in Ag nanoparticles and optical interference

Silver nanoparticles have been embedded at a few nanometer distance from the free surface of titania/silica multilayers using low energy ion beam synthesis. Transmission electron microscopy shows the presence of 3 nm-sized crystalline particles. Reflectance spectroscopy on these composite substrates shows an increase of the light capture efficiency in the visible range. This behaviour is interpreted as a synergistic effect between plasmon polariton resonance and Fabry–Perot interferences. Plasmon-resonant Raman spectroscopy is deeply used to analyze, on one hand confinement of vibrations and electronic excitations in Ag NPs, and on the other hand coupling of polar TiO2 phonons with injected photo-generated carriers. It is shown how these new Ag/TiO2 nanocomposite films appear as very promising to enhance the efficiency and enlarge the spectral sensitivity of plasmo-electronics devices

Subsidies, Competition Laws And Politics: A Comparison of the E.U. and the U.S.A. European Policy Papers #2

[Introduction.] Both the EU and the US have laws and rules intended to promote competition by discouraging monopolies and both sets of rules have similar "anti-trust" character. In the case of the EU, Community law contains general antitrust provisions, provisions for the control of mergers and concentrations, provisions restricting State aids, and particular rules applying to public undertakings. American antitrust law covers similar ground with respect to competition, monopolies, mergers, collusive practices, price discrimination and exclusionary practices. However, American law says nothing about state aids or about preemptive control of subsidies by any level of government. The law's silence on this topic might seem paradoxical. Since the ideology behind antitrust is so clearly an exaltation of free competition in a market economy, one would expect an explicit and stringent restriction of subsidies in American law, alongside the suspicion of economic concentration that is so apparent. But the very strength of the ideology may itself explain the law's silence: the notion of government subsidy - at least so described - is sufficiently alien that lawmakers have not even paused to consider its prohibition or restriction

Metal-TiO2 nanocomposites towards efficient solar-driven photocatalysis

Water, together with energy and food, has been addressed as one of the main urgent problem of humanity. The reduction of fresh clean water sources will definitely lead to huge issues in the next future, especially in developing countries. The conventional wastewater treatments suffer some limitations related to the effectiveness in decontamination (mechanical filtration), in the heavy use of chemicals (chlorination), or in elevate operational costs and energy requirements (desalination and reverse osmosis). In this sense, new materials such as nanocomposites may overcome these issues taking advantage of the peculiar properties of materials at nanoscale. Research on novel nanotechnologies must bring advances in order to contrast and prevent water scarcity and pollution. In order to be effective, these nanotechnologies should run at low operational cost, even in places unequipped by strong infrastructures and in concert with conventional cheap methodologies. Among the alternative water purification methods, TiO2-based photocatalysis has attracted great attention due to material stability, abundance, non-toxicity and high decontamination efficiency. In this material, electron-hole pairs, generated by light absorption, separate from each other and migrate to catalytically active sites at the surface of the photocatalyst. Photogenerated carriers are able to induce the water splitting reaction and, consequently, to decompose organic pollutants. The main deficiency of this material, related to its large band gap, is that only the UV fraction of the solar spectrum is effective to this purpose. Several approaches have been proposed to overpass this issue and, among them, the use of metal-TiO2 nanocomposites with proper nanostructurarion seems very promising for water purification strategies. Aim of this work is to investigate the possibility to develop efficient solar-driven TiO2 photocatalyst taking advantage of metallic nanostructures to efficiently couple the incident light to the photoactive semiconductor. Two approaches have been followed: TiO2 nanoparticles obtained via pulsed laser ablation in liquid and optical engineering of multilayered metal-TiO2 thin films. The first approach maximizes the exposed surface, thus enhancing the photocatalytic efficiency. However, in this case nanomaterials is dispersed in the surrounding environment, and in order to avoid this drawback we have investigated, as second approach, the use of metal-TiO2 thin films

Sine Wave Filters Design for AC Motor Drives with Genetic Algorithms

This paper proposes a suitable design methodology of the filter used at the output of inverters for AC motor drives. While it allows to achieve the best tradeoff among different design constraints that are difficult to include in standard design methods, such an approach is able to simultaneously consider several technical issues such as losses and voltage drops of the filter, total harmonic distortion of currents and voltages as well as economic aspects. Accordingly, the proposed procedure determines the optimal values of the filter parameters by exploiting simulations of accurate model of the electrical drive and genetic algorithms. Hence, no rough approximations or complex analytical calculations are performed to suitably design the inverter output filter. The method was validated by means of various tests performed on two different induction motor drives, considering some significant design constraint scenarios

A High Efficiency Interleaved PFC Front - End Converter for EV Battery Charger

Nowadays, an increasingly present application in the automotive field is the battery charger that usually consists of two high efficiency parts: an AC/DC converter with power factor correction (PFC) capability and a DC/DC converter. In this paper, a three-channel interleaved Power Factor Correction (PFC) based on a new digital controller STNRGPF01 operating in Continuous Conduction Mode (CCM) is presented addressing high efficiency. In the considered applications, the most challenging control issues are the input current control and the fast overcurrent protections. Exploiting mixed signal control approach some benefits have been obtained and confirmed by experimental results on a 3 kW prototype

Multi-Criteria Experimental Comparison of Batteries Circuital Models for Automotive Applications

Electrochemical batteries used in energy storage systems provide a significant contribution to the development of smart grids and green transportation. In recent years, intensive research activities have been oriented to the optimal management of energy storage systems for power electronics applications in fast growing industrial sectors as EVs and HEVs. The accurate modeling of electrochemical batteries is fundamental in the design of control algorithms applied to energy storage systems. Focusing on automotive applications, in this paper a comprehensive analysis of ESS models based on equivalent electric circuits using a multi-criteria approach is presented. An extensive experimental validation has been carried out to evaluate the performance of battery models in automotive applications

On the Lifetime Estimation of SiC Power MOSFETs for Motor Drive Applications

This work presents a step-by-step procedure to estimate the lifetime of discrete SiC power MOSFETs equipping three-phase inverters of electric drives. The stress of each power device when it is subjected to thermal jumps from a few degrees up to about 80 °C was analyzed, starting from the computation of the average power losses and the commitment of the electric drive. A customizable mission profile was considered where, by accounting the working conditions of the drive, the corresponding average power losses and junction temperatures of the SiC MOSFETs composing the inverter can be computed. The tool exploits the Coffin–Manson theory, rainflow counting, and Miner’s rule for the lifetime estimation of the semiconductor power devices. Different operating scenarios were investigated, underlying their impact on the lifetime of SiC MOSFETs devices. The lifetime estimation procedure was realized with the main goal of keeping limited computational efforts, while providing an effective evaluation of the thermal effects. The method enables us to set up any generic mission profile from the electric drive model. This gives us the possibility to compare several operating scenario of the drive and predict the worse operating conditions for power devices. Finally, although the lifetime estimation tool was applied to SiC power MOSFET devices for a general-purpose application, it can be extended to any type of power switch technology