Schaetzung der Verkehrsbeziehungen bei unvollstaendiger Information und deren Anwendung bei der Verkehrssteuerung

Available from TIB Hannover: F02B909 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Flexible NiO–Graphene–Carbon Fiber Mats Containing Multifunctional Graphene for High Stability and High Specific Capacity Lithium-Ion Storage

An electrode’s conductivity, ion diffusion rate, and flexibility are critical factors in determining its performance in a lithium-ion battery. In this study, NiO–carbon fibers were modified with multifunctional graphene sheets, resulting in flexible mats. These mats displayed high conductivities, and the transformation of active NiO to inert Ni⁰ was effectively prevented at relatively low annealing temperatures in the presence of graphene. The mats were also highly flexible and contained large gaps for the rapid diffusion of ions, because of the addition of graphene sheets. The flexible NiO–graphene–carbon fiber mats achieved a reversible capacity of 750 mA h/g after 350 cycles at a current density of 500 mA/g as the binder-free anodes of lithium-ion batteries. The mats’ rate capacities were also higher than those of either the NiO–carbon fibers or the graphene–carbon fibers. This work should provide a new route toward improving the mechanical properties, conductivities, and stabilities of mats using multifunctional graphene

Indefinite by Nature: From Ultraviolet to Terahertz

A class of strongly anisotropic materials having their principal elements of dielectric permittivity or magnetic permeability tensors of opposite signs, so-called indefinite or hyperbolic materials, has recently attracted significant attention. These materials enabled such novel properties and potential applications as all-angle negative refraction, high density of states, and imaging beyond the diffraction limit using a so-called hyperlens. While several studies identified a few examples of negative refractions in birefringent crystals existing in nature, the majority of optical materials with hyperbolic dispersion relations known to date are engineered composite materials, “metamaterials”, such as metal-dielectric subwavelength multilayered structures or metal nanowires in a dielectric matrix. In this paper, we investigate naturally existing hyperbolic materials with indefinite permittivity for a range of frequencies from terahertz to ultraviolet. These include graphite, MgB₂, cuprate, and ruthenate. Spectroscopic ellipsometry is used to characterize the dielectric properties of graphite and MgB₂, and a fitting method based on reflectance spectra is used to determine the indefinite permittivity of the cuprate and ruthenate. Lastly, we discuss the mechanisms behind indefinite properties of these materials

How Well Have China’s Recent Five-Year Plans Been Implemented for Energy Conservation and Air Pollution Control?

This study evaluates how well China’s 11th and 12th Five-Year Plans have been implemented in terms of energy conservation and air pollution control and deconstructs the effects of the economic, energy, and environmental policies included in the Plans. A “counterfactual” comparative-scenario method is deployed, which assumes a business as usual scenario in which the changes in economic, energy, and environmental parameters are “frozen”, and then reactivates them one by one, with the help of LEAP modeling. It is found that during the 11th Five-Year Plan period, the binding targets were basically achieved. Economic growth put a great strain upon the energy demand and the environment, but energy policy made a decisive contribution by promoting energy efficiency and structure. Environmental policy promoted the deployment of end-of-pipe treatment which led to the control of certain air pollutants but at the expense of an increase in energy use and in the emission of other pollutants. During the ongoing 12th Five-Year Plan period, energy policy’s potential for efficiency improvement is shrinking, but economic policy is restraining economic growth thus making a positive contribution. Environmental policy attempts to enforce multipollutant reduction, but there is still insufficient focus on the cocontrol of different pollutants and CO₂

Synthesis of Chiral Pyrazolone and Spiropyrazolone Derivatives through Squaramide-Catalyzed Reaction of Pyrazolin-5-ones with <i>o</i>‑Quinone Methides

A bifunctional squaramide-catalyzed reaction of pyrazolin-5-ones with <i>o</i>-quinone methides in situ generated from 2-(1-tosylalkyl)­phenols has been successfully developed, providing a facile access to chiral pyrazolones with high enantioselectivities. In addition, the chiral spiropyrazolones with adjacent tertiary and quaternary stereogenic centers can also be obtained through cascade chlorination/cyclization of the chiral pyrazolones

Theoretical curves (solide lines) and measured results (solide squares and solide triangles) of <i>I-V</i> characteristics at voltage scan rates of 1 V/s for: (a) V_max=10 and 14 V, (b) V_max=17 V.

<p>Theoretical curves (solide lines) and measured results (solide squares and solide triangles) of <i>I-V</i> characteristics at voltage scan rates of 1 V/s for: (a) V_max=10 and 14 V, (b) V_max=17 V.</p

<i>I-V</i> characteristics of NiO for V_max =15 V (a) measured at voltage scan rate of 0.1V/s; (b)measured at voltage scan rate of 0.1, 1, and 3 V/s; (c) at different temperatures: 283, 298 and 323 K; (d) with different sample thicknesses: 0.4, 0.5, 0.6, 0.7, and 0.9 mm.

<p><i>I-V</i> characteristics of NiO for V_max =15 V (a) measured at voltage scan rate of 0.1V/s; (b)measured at voltage scan rate of 0.1, 1, and 3 V/s; (c) at different temperatures: 283, 298 and 323 K; (d) with different sample thicknesses: 0.4, 0.5, 0.6, 0.7, and 0.9 mm.</p

Three continuous cycles of <i>I-V</i> loops for sample encapsulated with expanded polyethylene with V_max=15V at a voltage scan rate of 1 V/s.

<p>Three continuous cycles of <i>I-V</i> loops for sample encapsulated with expanded polyethylene with V_max=15V at a voltage scan rate of 1 V/s.</p

XRD patterns of NiO sintered at 1300 °C.

<p>XRD patterns of NiO sintered at 1300 °C.</p

Plot of resistance as a function of temperature.

<p>The solid line is the fitting curve while the solid squares are experimental results.</p