Actual
state of THE
(PDF 1916k)
Abstract: In this paper we
describe the actual state of Danube Delta Biosphere Reserve, using
aerospace
and GPS data. The Danube Delta Biosphere Reserve is situated in the
south-eastern part of
Key words:
АКУСТИЧНИ
ПРОБЛЕМИ НА ТРАМВАЙНИЯ ТРАНСПОРТ В
ГОЛЕМИТЕ ГРАДОВЕ
Н. Николов
ACOUSTICAL
PROBLEMS OF TRAM TRAFFIC IN
BIG CITIES
(PDF 3105k)
Abstract: Tram traffic is one of the main
sources of noise in cities. Compliance with noise level standards at the premises of
buildings located on bilateral narrow streets is a serious problem. Its solution will require
precise acoustical calculations which take into account all factors. The existing legislation does
not meet the complexity of the problem. In the material are exposed new
solutions to acoustic problems of tram transport in cities.
Keywords: Tram traffic, noise level, acoustical calculations
А. Симеонова, Ж. Бекярова, Р. Чутуркова
Investigations
of the river Kamchiya impact
over the
(PDF 112k)
Abstract: The status
of river Kamchiya was investigated for 2006- 2010y. period
at two monitoring stations
-“Poda” and “the Mouth”
which are
the nearest one to the Varna Black sea coast. Ammonium, nitrite and
nitrate
nitrogen; phosphate; Dissolved Oxygen
(DO),
Biochemical Oxygen Demand (BOD5),
Chemical Oxygen Demand (COD), water hardness and pH were analyzed. With regard to the
national threshold limits for II category water body the river was
characterized with high oxygen concentrations, low ammonium, nitrate and phosphate concentrations. Low biodegradable organic substances were
determined according to the values of BOD5 and COD. High nitrite concentrations,
approximately 3 times above the limits were measured at the monitoring
stations
for the period. Regarding the influence of the river over the sea coast
status
nutrients’ concentration above the threshold limits for coastal waters
were
measured. At the “Mouth” station the nitrite nitrogen was 3 times above
the
limit, the nitrate nitrogen from 1,2 to 1,8 times and the phosphates
from 3 to
6 times, which exhibited considerable influence of the river over the
sea
coast.
Keywords: monitoring, r. Kamchiya, nutrients,
organic substances, threshold limits
Н. Крумов, А. Ангелов, К. Постен
COMPARATIVE
STUDY OF YEAST STRAINS’ POTENTIAL TO ACCUMULATE CADMIUM IONS –
A PERSPECTIVE
PATHWAY FOR FUTURE BIOTECHNOLOGICAL
NANOPARTICLE FORMATION
(PDF
1810k)
Abstract. Nanoparticles’ unique properties and applications
define the practical interest towards them and the consequent
elaboration of
different synthesis strategies. Understanding the process of
biomineralization
and the identification of microorganisms capable of producing
nanoparticles
under defined conditions, unveils new perspectives for the
nanotechnology and
facilitate its fusion with biotechnology. The main objective of the
present
scientific work was to compare selected biosynthetic and metabolic
activities
of yeast strains isolated from soil. As the bionanoparticle-formation
mechanisms in yeasts are strain- and cultivation conditions-specific,
the
foreseen experiments aimed eventually to recognize and introduce new
promising
yeast strains with high potential for the synthesis of CdS
bionanoparticles.
Soil-isolated yeast strain designated as S. pombe NK05/2 demonstrated
highest levels of specific cadmium accumulation – 8.8 and 13.75 mg.g-1
BDM (bio dry mass) for both media tested, and exhibit the best
biosynthetic
characteristics.
Keywords:
nanoparticles,
yeast, cadmium, biomineralization
РЕЗУЛТАТИ ОТ ПРОТИВОЕРОЗИОННИТЕ
ЗАЛЕСЯВАНИЯ В РАЙОНА НА КЪРДЖАЛИ
Б. Янгьозов
RESULTS
OF ANTI-EROSION AFFORESTATIONS IN KARDZHALI REGION
(PDF
1812k)
Abstract:
Forests
take important part in the process of soil formation
and protection. Devastation of plant
vegetation, however, usually
leads to the development of intensive erosion, which in the mountains can be limited only by
restoration of forest cover.
An example of vast areas of
destroyed
forests and eroded lands, followed by large-scale afforestation is the
region
of Kardzhali. Field measurement
and analytical methods were used for
analyzing the
results of the
plantations, established
to control the erosion in the region. Silviculture
processes, running in anti-erosion forest
plantations, their species composition and their role in habitat
restoration were investigated. The analysis results
provide guidance for future management of these
plantations to ensure their function to
control the erosion, as well as selection
of forest tree species
for future afforestations accordingly to the
specific characteristics of the region.
Keywords: erosion, habitat,
forest tree plantations, afforestation
ИЗСЛЕДВАНЕ НА
ЕКОЛОГИЧНАТА
ДИНАМИКА НА ГОРСКАТА РАСТИТЕЛНОСТ В РАЙОНА НА ИЗТОЧНИ РОДОПИ НА БАЗАТА
НА
СПЪТНИКОВА, GPS И НАЗЕМНА ИНФОРМАЦИЯ
М.
Любенова, Р. Недков, И.
Иванова, А. Шикаланов, М. Захаринова, Н. Георгиева, М. Димитрова, Е.
Иванова,
В. Янчев, К. Радева, Н. Станкова, Р. Цонева
STUDY ON ECOLOGICAL DYNAMICS
OF
(PDF 1378k)
Abstract: In this paper a study of forest vegetation in the
Key
words: ecological dynamics, forest
community,
satellites data, terrestrial data,
ВЪЗМОЖНОСТИТЕ НА МИКРОВОДОРАСЛИТЕ ЗА
ПРОИЗВОДСТВО НА БИОГОРИВА
К. Лахчев, М. Дойнова
MICROALGAE
ARE
PROMISING SOURCE OF
BIOFUELS
(PDF 624k)
Abstract:
During the last decades microalgae emerge as promising organisms for
industrial
biofuel production. Microalgae are a large and diverse group of
photosynthetic
microorganisms capable to convert sun light and carbon dioxide into
carbohydrates and oxygen. The reasons for steadily increasing attention
to
microalgae are their rapid growth and ability to accumulate high amount
of
lipids. Lipids can be easily extracted and used as biofuels without
significant
and expensive treatments. Additionally microalgae have some attractive
characteristics such as their ability to utilize carbon dioxide from
industrial
gases and to purify waste waters. Microalgae can be cultivated on areas
that
are not suited for agricultural plants; their biomass is a subject of
bio-degradation and can be used as food, feed and fine chemicals. However, most of the widely distributed
species in nature can’t be used as biofuel donors, because they don’t
possess
the necessary qualities for inexpensive production. Promising species
also
occur, but they are objects of genetic manipulations with the purpose
to be
created ‘domesticated’ algae for biofuel manufacturing. This review
describes
some of the main microalgal species with biotechnological and genetic
potential
and the molecular manipulations for improving their growth rates and
lipid
content. The main difficulties that appear in front of scientists are
also discussed.
АНАЛИЗ НА
ПОМПЕНО АКУМУЛИРАЩА ВОДНОЕЛЕКТРИЧЕСКА ЦЕНТРАЛА КЪМ СИСТЕМА С
ВЕТРОГЕНЕРАТОР И
ФОТОВОЛТАИК ЗА ВНЕДРЯВАНЕ В ЕЛЕКТРИЧЕСКАТА МРЕЖА
ANALYSIS
OF PUMPED
HYDROELECTRIC STORAGE FOR A WIND/PV SYSTEM FOR GRID INTEGRATION
(PDF 971k)
Abstract: This paper
deals with the pumping storage system analysis.
The water reservoir serves for daily and seasonal energy storage, thus
basically solving the problem of energy storage, which is the biggest
problem
of wider use of renewable energy sources. The electrical energy
produced in
excess by the renewable energy system is converted in potential energy
by
pumping water to a higher elevation where it can be stored indefinitely
and
then released to pass through hydraulic turbines and generate
electricity. The
estimation of the stored energy, the nominal electrical power of the
hydroelectric plant and the evaporation rate of the water reservoir is
presented.
Keywords: solar
energy; wind energy; hybrid systems; pumped storage.
И. Иванов, А.
Саравананакумар, К. Кумар, П.
Калейчев
INITIAL RESULTS
OF STUDIES AND
POSSIBILITIES FOR BIOMASS GASIFICATION IN
AND
(PDF 330k)
Abstract. The
use of biomass as energy source
has high priority in order to comply with the Kyoto Protocol for global
reduction
of the greenhouse emission. As result of scientific contacts and
studies of
researchers from
