34 research outputs found
The Concept of Sustainable Development and Its Impact on the Shaping of Modern International Relations through Global Agreements
The goal of this article is a depiction of the process of the molding of the concept of sustainable development as well as a look at the influence that this concept has exerted on contemporary international politics, especially taking into account agreements of worldwide scope. This article is also an effort at demonstrating that the foundations of the concept of sustainable development can be traced to certain economic theories. The final section of this article is devoted to the characteristics of individual conferences initiated by the United Nations in order to promote enduring and sustainable development on a world scale. Also presented are the achievements of the individual conferences and their roles in demarcating universally obligatory principles and standards of sustainable development.Celem niniejszego artykułu jest scharakteryzowanie genezy kształtowania się Koncepcji Zrównoważonego Rozwoju, a także wskazanie, jaki wpływ miała ona na ukształtowanie się stosunków międzynarodowych w zakresie ochrony środowiska i rozwiązywania problemów społecznych. Przedmiotem analizy są także teorie ekonomiczne, które stały się fundamentem dla wykrystalizowania się koncepcji zrównoważonego rozwoju. Poniższy artykuł jest także próbą wykazania, iż konferencje organizowane przez ONZ na rzecz trwałego i zrównoważonego rozwoju, stały się siła napędową do rozpowszechnienia tej koncepcji w skali światowej
Heat capacity and phonon mean free path of wurtzite GaN
We report on lattice specific heat of bulk hexagonal GaN measured by the heat
flow method in the temperature range 20-300 K and by the adiabatic method in
the range 5-70 K. We fit the experimental data using two temperatures model.
The best fit with the accuracy of 3 % was obtained for the temperature
independent Debye's temperature {\rm K} and Einstein's
temperature {\rm K}. We relate these temperatures to the
function of density of states. Using our results for heat conduction
coefficient, we established in temperature range 10-100 K the explicit
dependence of the phonon mean free path on temperature . Above 100 K, there is the evidence of contribution of the Umklapp
processes which limit phonon free path at high temepratures. For phonons with
energy {\rm K} the mean free path is of the order 100
{\rm nm}Comment: 5 pages, 4 figure
Analysis of Experimental Conditions for Simultaneous Measurements of Transport and Magnetotransport Coefficients of High Temperature Superconductors
Experimental conditions for simultaneous measurements of transport
coefficients of high temperature superconductors in zero and non-zero magnetic
fields are analysed. Test measurements of the thermal conductivity, the
thermoelectric power and the Nernst - Ettingshausen effect of a textured Bi2212
sample are reported in an external magnetic field of 2T. Errors related to
parameters of the thermocouple used and to the spurious heat flows are
discussed for a new experimental set-up built based on a closed cycle helium
refrigerator. Possible optimising of experimental conditions is suggested.Comment: 9 pages + 4 figures. accepted for publication in Cryogenic
Dyrektor szkoły - koncepcje i wyzwania. Między teorią a praktyką.
Publikacja powstała w ramach projektu „Przywództwo i zarządzanie w oświacie – opracowanie i wdrożenie systemu kształcenia i doskonalenia dyrektorów szkół/placówek”. W niniejszej książce staraliśmy się dowieść, że różne spojrzenia na naturę pracy dyrektora szkoły nie wykluczają się nawzajem, że mogą współistnieć nie tylko dla pełnej jego samorealizacji w wielu rolach, ale że w codziennej praktyce nierzadko wypełniają już postulaty tak przywództwa, jak i bieżącego administrowania, z zarządzania szkołą. Uporządkowanie pojęć i terminów, ale także sformułowanie postulatów pod adresem kształcenia i doskonalenia zawodowego dyrektorów szkół, określenie pożądanych u dyrektora cech, kompetencji, przy jednoczesnym zwróceniu uwagi na niespójność rozwiązań prawnych czy niejednoznacznym treściowo adoptowaniu dla polskich potrzeb terminów z języka angielskiego, to niewątpliwie nowość w polskim spojrzeniu na omawiane zagadnienia. To walor tej książki i – jak zakładamy – spory argument za tym, by wziąć ją do ręki, zapoznać się z jej treścią i po prostu polubić ją
Excess thermal resistivity in N₂–CO solid solution at low carbon monoxide concentration
The results of measurements of the thermal conductivity of pure and carbon-monoxide-doped nitrogen crystals, for samples containing up to 0.7% of CO molecules, in the temperature range 1.2–26 K are presented. From the preliminary analysis it results that the interaction of phonons with admixture molecule featuring the same mass, as the host molecule, is relatively weak and depends weakly on the admixture concentration within investigated range of carbon monoxide in nitrogen crystal
Thermal conductivity of donor-doped GaN measured with 3ω and stationary methods
The thermal conductivity of three single crystal samples of n-type gallium nitride with electron densities of
4.0⋅10¹⁶, 2.6⋅10¹⁸, and 1.1⋅10²⁰ cm⁻³ has been determined in the temperature range 4–320 K. The measurements
were carried out within the ab plane using the stationary method. The thermal conductivity depends strongly on
the donor concentration. The analysis within the Callaway approach and the Debye model shows a significant influence
of phonon–electron scattering on the thermal conductivity of the samples. In addition, some preliminary
results obtained along the c axes of GaN layered samples are presented. The latter measurements have been carried
out using the 3ω method
Genome biology of the paleotetraploid perennial biomass crop Miscanthus
Miscanthus is a perennial wild grass that is of global importance for paper production, roofing, horticultural plantings, and an emerging highly productive temperate biomass crop. We report a chromosome-scale assembly of the paleotetraploid M. sinensis genome, providing a resource for Miscanthus that links its chromosomes to the related diploid Sorghum and complex polyploid sugarcanes. The asymmetric distribution of transposons across the two homoeologous subgenomes proves Miscanthus paleo-allotetraploidy and identifies several balanced reciprocal homoeologous exchanges. Analysis of M. sinensis and M. sacchariflorus populations demonstrates extensive interspecific admixture and hybridization, and documents the origin of the highly productive triploid bioenergy crop M. x giganteus. Transcriptional profiling of leaves, stem, and rhizomes over growing seasons provides insight into rhizome development and nutrient recycling, processes critical for sustainable biomass accumulation in a perennial temperate grass. The Miscanthus genome expands the power of comparative genomics to understand traits of importance to Andropogoneae grasses
Heat capacity anomalies of the molecular crystal 1-fluoro-adamantane at low temperatures
Disorder–disorder phase transitions are rare in nature. Here, we present a comprehensive low-temperature experimental and theoretical study of the heat capacity and vibrational density of states of 1-fluoro-adamantane (C10H15F), an intriguing molecular crystal that presents a continuous disorder–disorder phase transition at T = 180 K and a low-temperature tetragonal phase that exhibits fractional fluorine occupancy. It is shown that fluorine occupancy disorder in the low-T phase of 1-fluoro-adamantane gives rise to the appearance of low-temperature glassy features in the corresponding specific heat (i.e., “boson peak” -BP-) and vibrational density of states. We identify the inflation of low-energy optical modes as the main responsible for the appearance of such glassy heat-capacity features and propose a straightforward correlation between the first localized optical mode and maximum BP temperature for disordered molecular crystals (either occupational or orientational). Thus, the present study provides new physical insights into the possible origins of the BP appearing in disordered materials and expands the set of molecular crystals in which “glassy-like” heat-capacity features have been observed