Environmental problem in organization of works related to electroplating of parts

Problem statement: Ecological problem in the application of galvanic coatings during the manufacture of electronic equipment for the Navy. The aim of the work is to analyze the applied galvanic coatings in the manufacture of radioelectronic equipment (CEA) and a description of the environmental problem in the organization of work related to the application of galvanic coatings to parts within the city of St. Petersburg. Novelty: consists in a description of the conflict of legislative requirements regarding licensing of hazardous industries and proposals to rectify the situation. The result: it is necessary to allow enterprises located within the city limits to re-equip galvanic production to improve the ecological condition of the city. Practical significance: improving the environmental situation in the city of St. Petersburg

Magnetic Field-Induced Lattice Effects in a Quasi-2D Organic Conductor Close to the Mott Metal-Insulator Transition

We present ultra-high-resolution dilatometric studies in magnetic fields on a quasi-two-dimensional organic conductor $\kappa$-(D8-BEDT-TTF)$_{2}$Cu[N(CN)$_{2}$]Br, which is located close to the Mott metal-insulator (MI) transition. The obtained thermal expansion coefficient, $\alpha(T)$, reveals two remarkable features: (i) the Mott MI transition temperature $T_{MI}$ = (13.6 $\pm$ 0.6)\,K is insensitive to fields up to 10\,T, the highest applied field; (ii) for fields along the interlayer \emph{b}-axis, a magnetic-field-induced (FI) phase transition at $T_{FI}$ = (9.5 $\pm$ 0.5)\,K is observed above a threshold field $H_c \sim$ 1 T, indicative of a spin reorientation with strong magneto-elastic coupling.Comment: 5 pages, 4 figure

The salience of comparison standards and the activation of social norms: consequences for judgments of happiness and their communications

'Zwei Untersuchungen wurden durchgeführt, in denen Berichte über das eigene subjektive Wohlbefinden beeinflußt werden a) durch die Augenfälligkeit eines Vergleichsstandards und b) durch die Aktivierung einer sozialen Norm im Kontext der Urteilsabgabe. Wir fanden, daß sich die Versuchspersonen in Anwesenheit einer anderen Person, der es vergleichsweise schlechter ging, als glücklicher einschätzten. Dieser Kontrasteffekt trat verstärkt auf, wenn die Aufmerksamkeit der Vpn beim Ausfüllen des Fragebogens durch ein natürliches Sitzarrangement auf die Vergleichsperson gerichtet war. Die Ergebnisse des zweiten Experiments, in dem die Darbietungsform der Befragung (anonym vs. offen) und der offensichtliche Gesundheitszustand der Vergleichsperson (körperbehindert oder nicht) variiert wurde, zeigen, daß solche vergleichende Urteile nicht geäußert werden, wenn die Antworten dem körperbehinderten Versuchsteilnehmer gegenüber offen geäußert werden müssen. Zusammengenommen machen beide Untersuchungen deutlich, daß kognitive und kommunikative Prozesse gleichermaßen beachtet werden müssen, um die Determinanten von Urteilen des subjektiven Wohlbefindens zu verstehen.' (Autorenreferat)'Two studies were conducted in which subjects' reports of their own happiness were influenced a) by the salience of comparison standards and b) by the social norm that was activated in the context of communicating those judgments. It was found that the presence of another person who was relatively worse off led to more positive judgments of the subjects' own happiness. This contrast effect was increased when subjects' attention was directed toward the comparison person by a natural seating arrangement at the time the questionnaire had to be filled out. The results of the second study in which the mode of administration (private vs. public) and the apparent state of health of the comparison person were varied (physically handicapped or not), show that such contrastive judgments may not be uttered when the judgment has to be reported to the handicapped confederate. Taken together, these studies demonstrate how both cognitive and communicative mechanisms must be taken into account to understand the determinants of judgments of subjective well-being.' (author's abstract

Ferromagnetism in Correlated Electron Systems: Generalization of Nagaoka's Theorem

Nagaoka's theorem on ferromagnetism in the Hubbard model with one electron less than half filling is generalized to the case where all possible nearest-neighbor Coulomb interactions (the density-density interaction $V$, bond-charge interaction $X$, exchange interaction $F$, and hopping of double occupancies $F'$) are included. It is shown that for ferromagnetic exchange coupling ($F>0$) ground states with maximum spin are stable already at finite Hubbard interaction $U>U_c$. For non-bipartite lattices this requires a hopping amplitude $t\leq0$. For vanishing $F$ one obtains $U_c\to\infty$ as in Nagaoka's theorem. This shows that the exchange interaction $F$ is important for stabilizing ferromagnetism at finite $U$. Only in the special case $X=t$ the ferromagnetic state is stable even for $F=0$, provided the lattice allows the hole to move around loops.Comment: 13 pages, uuencoded postscript, includes 1 table and 2 figure

Effects of Next-Nearest-Neighbor Hopping on the Hole Motion in an Antiferromagnetic Background

In this paper we study the effect of next-nearest-neighbor hopping on the dynamics of a single hole in an antiferromagnetic (N\'{e}el) background. In the framework of large dimensions the Green function of a hole can be obtained exactly. The exact density of states of a hole is thus calculated in large dimensions and on a Bethe lattice with large coordination number. We suggest a physically motivated generalization to finite dimensions (e.g., 2 and 3). In $d=2$ we present also the momentum dependent spectral function. With varying degree, depending on the underlying lattice involved, the discrete spectrum for holes is replaced by a continuum background and a few resonances at the low energy end. The latter are the remanents of the bound states of the $t-J$ model. Their behavior is still largely governed by the parameters $t$ and $J$. The continuum excitations are more sensitive to the energy scales $t$ and $t_1$.Comment: To appear in Phys. Rev. B, Revtex, 23 pages, 10 figures available on request from [email protected]