Exact ground-state correlation functions of the one-dimensional strongly correlated electron models with the resonating-valence-bond ground state

We investigate the one-dimensional strongly correlated electron models which have the resonating-valence-bond state as the exact ground state. The correlation functions are evaluated exactly using the transfer matrix method for the geometric representations of the valence-bond states. In this method, we only treat matrices with small dimensions. This enables us to give analytical results. It is shown that the correlation functions decay exponentially with distance. The result suggests that there is a finite excitation gap, and that the ground state is insulating. Since the corresponding non-interacting systems may be insulating or metallic, we can say that the gap originates from strong correlation. The persistent currents of the present models are also investigated and found to be exactly vanishing.Comment: 59 pages, REVTeX 3.0, Figures are available on reques

Nutzung von Prozessen der Biosorption und Akkumulation zur Metallabtrennung und Rueckgewinnung aus belasteten Abwaessern mit dem Ziel der Umweltsanierung Abschlussbericht

Es wurden Grundlagenuntersuchungen zur Biosorption von umweltrelevanten Schwermetallen mit verschiedenen mikrobiellen Adsorbentien durchgefuehrt und an technischen Abwaessern Technologievorschlaege erarbeitet. Zur Verbesserung der Technologie von Biosorptionsprozessen wurden Moeglichkeiten der Steigerung der Sorptionsleistung von Biosorbentien erarbeitet und Untersuchungen zur Immobilisierung der biologischen Adsorbentien durchgefuehrt. (orig.)Fundamental investigations into the biosorption of environmentally relevant heavy metals were carried out with different microbial adsorbents, and processes were proposed for industrial effluents. In order to improve the technology of biosorption processes, attempts were made to improve the sorption efficiency of biological sorbents, and investigations were carried out on the immobilisation of biological adsorbents. (orig.)Available from TIB Hannover: D.Dt.F. QN1(7,10) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Forschung und Technologie (BMFT), Bonn (Germany)DEGerman

Abwasser aus der Reinigung und Desinfektion von Melkanlagen Charakteristik und Moeglichkeiten der Behandlung. Abschlussbericht

SIGLEAvailable from TIB Hannover: F00B913 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekATV-DVWK Abwasser - Abfall - Gewaesserschutz, Hennef (Germany)DEGerman

Senolytics prevent mt-DNA-induced inflammation and promote the survival of aged organs following transplantation

Organ transplantation involving aged donors is often confounded by reduced post-transplantation organ survival. By studying both human organs and mouse transplantation models, here the authors show that pretreating the donors with senolytics to reduce mitochondria DNA and pro-inflammatory dendritic cells may help promote survival of aged organs

Reducing Spurious Diapycnal Mixing in Ocean Models

Transport algorithms of numerical ocean circulation models are frequently exhibiting truncation errors leading to spurious diapycnal mixing of water masses. The chapter discusses methods that might be useful in diagnosing spurious diapycnal mixing and describes some approaches that might be helpful for its reduction. The first one is related to the use of the Arbitrary Lagrangian Eulerian (ALE) vertical coordinate which allows the implementation of vertically moving meshes that may partly follow the isopycnals even if the basic vertical coordinate differs from isopycnal. The second approach relies on modified advection schemes with the dissipative part of the transport operators directed isopycnally. Finally the third approach deals with new efficient and stable advection algorithms of arbitrary high order based on the WENO- ADER method, which can be applied to both structured and unstructured meshes. While practical benefits of using the reviewed approaches depend on applications, there are indications that equipping present state- of-the-art ocean circulation models with them would lead to reduced spurious transformations