ABSTRACT
We show that optical properties change when the fullerene structures of Au32, Cu32and Ag32inflate and deflate. We first observe significant differences in the extinction spectra employing a classical approach based on the Green's dyadic method. By means of real-time time-dependent density functional theory. We continue to calculate the optical spectrum (OP) via aδ-kick simulation, comparing results with the ground-state energetic property the HOMO-LUMO (HL) gap. Red-shift of the OP is expected as the fullerenes inflate, with only ±10% change in the size. As the fullerene breathes, a 0.8 eV shift in the first peak position could be observed in the gold nanoparticle. Ag has a smoother behaviour than both Au and Cu. We have also found changes in the optical spectra can not be directly interpreted as a result of changes in the HL gap.
ABSTRACT
We here report the implementation of poly[(3-N-methylimidazoliumpropyl)methylsiloxane-co-dimethylsiloxane]iodides as suitable polymeric hosts for a novel class of in situ cross-linkable iodine/iodide-based gel-electrolytes for dye-sensitized solar cells. The polymers are first partially quaternized and then subjected to a thermal cross-linking which allows the formation of a 3D polymeric network which is accompanied by a dramatic enhancement of the ionic conductivity.
Subject(s)
Cross-Linking Reagents/chemistry , Gels/chemistry , Hydrocarbons, Iodinated/chemistry , Siloxanes/chemistry , Coloring Agents/chemistry , Electric Conductivity , Electrolytes/chemistry , Solar EnergyABSTRACT
Quantum stochastic methods based on effective wave functions form a framework for investigating the generally non-Markovian dynamics of a quantum-mechanical system coupled to a bath. They promise to be computationally superior to the master-equation approach, which is numerically expensive for large dimensions of the Hilbert space. Here, we numerically investigate the suitability of a known stochastic Schrödinger equation that is local in time to give a description of thermal relaxation and energy transport. This stochastic Schrödinger equation can be solved with a moderate numerical cost, indeed comparable to that of a Markovian system, and reproduces the dynamics of a system evolving according to a general non-Markovian master equation. After verifying that it describes thermal relaxation correctly, we apply it for the first time to the energy transport in a spin chain. We also discuss a portable algorithm for the generation of the coloured noise associated with the numerical solution of the non-Markovian dynamics.
ABSTRACT
Novel co-sensitizers have been structurally tailored and implemented in multi-sensitized devices demonstrating synergic efficiency enhancement attributable to improved light-harvesting as well as prevention of charge recombination.
Subject(s)
Coloring Agents/chemistry , Electric Power Supplies , Engineering , Solar Energy , Electron TransportABSTRACT
Stochastic methods are ubiquitous to a variety of fields, ranging from physics to economics and mathematics. In many cases, in the investigation of natural processes, stochasticity arises every time one considers the dynamics of a system in contact with a somewhat bigger system, an environment with which it is considered in thermal equilibrium. Any small fluctuation of the environment has some random effect on the system. In physics, stochastic methods have been applied to the investigation of phase transitions, thermal and electrical noise, thermal relaxation, quantum information, Brownian motion and so on. In this review, we will focus on the so-called stochastic Schrödinger equation. This is useful as a starting point to investigate the dynamics of open quantum systems capable of exchanging energy and momentum with an external environment. We discuss in some detail the general derivation of a stochastic Schrödinger equation and some of its recent applications to spin thermal transport, thermal relaxation, and Bose-Einstein condensation. We thoroughly discuss the advantages of this formalism with respect to the more common approach in terms of the reduced density matrix. The applications discussed here constitute only a few examples of a much wider range of applicability.
Subject(s)
Physics , Quantum Theory , Algorithms , Models, StatisticalABSTRACT
OBJECTIVE: The prognostic value of the nucleated red blood cell count at birth with respect to perinatal brain damage and neonatal outcome was assessed in infants at high risk of having neurologic damage. STUDY DESIGN: The nucleated red blood cell count at birth, pulsed Doppler ultrasonography in the cerebral arteries, cranial fontanelle sonograms, and neurodevelopmental status were evaluated in 337 newborn infants. RESULTS: The nucleated red blood cell count at birth was significantly higher (1) in neonates with abnormal Doppler ultrasonographic parameters for the cerebral arteries at 48 to 72 hours after birth than in healthy neonates, (2) in 6-month-old infants with sequelae of hypoxic-ischemic encephalopathy than in healthy infants, and (3) in 3-year-old children with abnormal developmental status than in those with no abnormalities at follow-up. Significant correlations were observed between the nucleated red blood cell count and gestational age, Apgar score at 1 and 5 minutes, pH, base deficit, fraction of inspired oxygen, blood oxygen content, and birth weight. CONCLUSIONS: The nucleated red blood cell count at birth not only reflects a response of the infant to perinatal hypoxia but is also a reliable index of perinatal brain damage.
Subject(s)
Brain Injuries/diagnosis , Cerebral Arteries/diagnostic imaging , Developmental Disabilities/diagnosis , Erythroblasts/pathology , Hypoxia/blood , Apgar Score , Brain Injuries/blood , Brain Injuries/diagnostic imaging , Case-Control Studies , Erythrocyte Count , Female , Heart Rate, Fetal , Humans , Infant, Newborn , Infant, Premature, Diseases/blood , Infant, Premature, Diseases/diagnosis , Infant, Premature, Diseases/diagnostic imaging , Male , Predictive Value of Tests , Pregnancy , Prognosis , Ultrasonography, Doppler, PulsedSubject(s)
Aortic Aneurysm/genetics , Aortic Dissection/genetics , Adult , Aged , Aorta, Abdominal , Aorta, Thoracic , Female , Humans , Male , Middle Aged , PedigreeSubject(s)
Chlorthalidone/therapeutic use , Hypertension/drug therapy , Oxprenolol/therapeutic use , Adult , Aged , Chlorthalidone/adverse effects , Chronic Disease , Clinical Trials as Topic , Double-Blind Method , Drug Combinations , Female , Humans , Hypokalemia/chemically induced , Male , Middle AgedSubject(s)
Atenolol/therapeutic use , Exercise Test , Hypertension/drug therapy , Methyldopa/therapeutic use , Propanolamines/therapeutic use , Adult , Blood Pressure/drug effects , Clinical Trials as Topic , Female , Heart Rate/drug effects , Humans , Male , Middle Aged , Oxygen Consumption/drug effects , Physical Exertion/drug effectsABSTRACT
1. The effect of a low-sodium diet and pharmacological therapy has been compared in eighty-one patients with mild hypertension. 2. Both pharmacological therapy and a low-sodium diet reduced lying and standing systolic and diastolic blood pressure significantly.