АНАЕРОБНА
БИОДЕГРАДАЦИЯ И КО-БИОДЕГРАДАЦИЯ НА ПТИЧИ ОТПАДЪЦИ: ПРЕДИЗВИКАТЕЛСТВА,
ОГРАНИЧЕНИЯ НА
ПРОЦЕСА И НОВОВЪЗНИКВАЩИ ВЪЗМОЖНОСТИ
Иван Симеонов, Венелин Хубенов
ANAEROBIC DIGESTION
AND CO-DIGESTION OF POULTRY WASTE: CHALLENGES, PROCESS
LIMITS, AND EMERGING OPPORTUNITIES
Ivan
Simeonov1, Venelin Hubenov1,2
2 Competence Center “Clean Technologies for a Sustainable Environment – Waters, Wastes, Energy for Circular Economy”, Sofia, Bulgaria
1 Contact details of corresponding author
e-mail: issim@abv.bg; issim@microbio.bas.bg
Abstract. The
poultry industries are growing rapidly due to its
availability of lean meat with low cholesterol content.
However, the problems also coming along with the poultry
manure production as a waste from poultry industries. Тhe
increase in the demand of poultry products have led to fast
and concentrated growth of the poultry industry, which
deliver superabundant manure supplies. Poultry waste is one
of the best organic manure and also much valuable resource.
At present the poultry farming supply vital sprig of animal
protein and also the most freely reared livestock species
amongst the all livestock species. In spite of its huge
benefits like production of meat, eggs and job generations
it frequently creates some environmental risks that
adversely affect both humans and animals, because the
poultry farming is the main cause of offensive odor, water,
soil, and air pollution. The conversion of poultry waste
into biogas and biofertilizer is considered one of the most
effective waste management and recycling strategies.
Keywords: poultry waste, environmental pollution,
chicken manure, AD, AcoD, complex mixtures, biogas
production, biofertilizer
ТОПОГРАФСКИ АНАЛИЗ НА ТЕРЕНА В ОБЛАСТТА PROTONILUS MENSAE НА МАРС ЧРЕЗ ФРАКТАЛНА РАЗМЕРНОСТ И ЛАКУНАРНОСТ
Росен Илиев, Бойко Рангелов
Rosen Iliev, Boyko Ranguelov
Space Research and Technology Institute, Bulgarian Academy of Sciences, Sofia, Bulgaria
Abstract: This study investigates the surface complexity of the
Protonilus Mensae region in the northern hemisphere of Mars
using an integrated approach based on fractal dimension (FD)
and lacunarity analysis. Digital elevation model (DEM) data
derived from the Mars Orbiter Laser Altimeter (MOLA), with a
spatial resolution of 463 m, were analyzed using Python-based
algorithms. Surface roughness was analyzed using a
variogram-based fractal method. The results show that the
topography of Protonilus Mensae exhibits fractal behavior,
with FD values ranging from 2.11 to 2.70 and a mean value of
2.35. Spatial patterns of FD reveal predominantly low to
moderate surface complexity. Lacunarity analysis was
employed to characterize spatial heterogeneity and the
distribution of topographic gaps. (Lacunarity means empty
spaces (gaps) in DEM with similar fractal dimensions but
different surface view.) The results show a strong
dependence of lacunarity on elevation, with maximum
heterogeneity occurring at intermediate elevations
associated with fretted (not smooth) terrain. Lower and
higher elevations exhibit reduced lacunarity. The combined
fractal and lacunarity results suggest that the present-day
morphology of Protonilus Mensae represents a degraded
landscape shaped by a balance between roughness-enhancing
processes and smoothing processes. This
integrated quantitative approach provides new insights into
the geomorphological evolution of not flat terrains on Mars.
Keywords: Protonilus Mensae, Mars, fractal dimension,
lacunarity, variogram, smooth terrains.
ОСТОЙНОСТЯВАНЕ НА СЕЛСКОСТОПАНСКИ ОТПАДЪЦИ ОТ ТАРО (Colocasia esculenta L) В ЕНЕРГИЙНО ПЛЪТНИ БРИКЕТИ: ОЦЕНКА НА КАЧЕСТВОТО НА УСТОЙЧИВОТО ГОРИВО
Арум Видиасмара, Ерна Стиани, Хайрил Ануар, Уини Ифтари, Курниа Уиди Астути, Попи Шри Лестари
VALORIZATION OF TARO (Colocasia esculenta L.) AGRICULTURAL WASTE INTO ENERGY DENSE BRIQUETTES: A SUSTAINABLE FUEL QUALITY ASSESSMENT1Department of Chemical
Analysis, Polytechnic of AKA Bogor, Bogor 16154,
Indonesia.
2 Department of Industrial Waste
Treatment, Polytechnic of AKA Bogor, Bogor 16154,
Indonesia.
3Department of Food Industry Quality
Assurance, Polytechnic of
AKA Bogor, Bogor 16154, Indonesia.
Abstract.
This study investigates the potential of taro
(Colocasia esculenta L.) peel, a significant
agricultural waste, as a raw material for high-quality
solid fuel briquettes. To optimize characteristics,
briquettes were pre-treated by oven-drying (90ºC-120ºC,
30-60 min) and assessed via proximate analysis, DSC, and
Ignition Rate testing. Results confirmed successful
property upgrades, identifying 120ºC for 45 minutes as
optimal for energy concentration. This condition yielded
the highest Fixed Carbon (55.08%) and total thermal output
(1,689.176 J/g by DSC), plus the maximum Ignition Rate
(0.0008778 g/second), confirming superior combustion
kinetics. The 120ºC variant's superior energy content and
confirmed thermal stability (onset 206.840ºC) establish it
as the most promising fuel. Findings validate the
technical feasibility of transforming taro peel waste into
an energy-dense solid fuel, demonstrating a viable
strategy for sustainable waste management and renewable
energy generation.
Keywords:
Taro
Peel Waste, Solid Fuel Briquettes, Valorization, Fixed
Carbon, Thermal Stability, Ignition Rate, DSC
ОПТИМИЗИРАНЕ НА ВЪЗРАСТТА ЗА РАЗСАЖДАНЕ ЗА ПОДОБРЕН ДОБИВ И КАЧЕСТВО НА СЕМЕНАТА ОТ СОРТОВЕТЕ ОРИЗ Т. АМАН В СУБТРОПИЧЕН БАНГЛАДЕШ: ПРОУЧВАНЕ НА СОРТОВИТЕ РЕАКЦИИ
Насир Удин Сойкот, М. Шариеутулах, Дийн Мохамад Дийпо, А. К. М. Рухул АминOPTIMIZING
TRANSPLANTING AGE FOR ENHANCED YIELD AND SEED QUALITY OF
T. AMAN RICE VARIETIES IN SUBTROPICAL BANGLADESH: A STUDY
ON VARIETAL RESPONSES
Nasir
Uddin Soykot1,*, Md. Sharieutullah1, Deen Mohammad Deepo2
& Dr.
A. K. M. Ruhul Amin3
1 Institute
of Seed Technology, Sher-E-Bangla Agricultural
University, Dhaka, Bangladesh
2 Department of Agricultural
Science, Daffodil International University, Dhaka,
Bangladesh
3 Dept.
of Agronomy, Sher-E-Bangla Agricultural University,
Dhaka, Bangladesh
Correspondence:
nasiruddinsoykot.sau.74@gmail.com*
Abstract. A field experiment was conducted during the Aman
season (July–December 2019) in a subtropical region of
Bangladesh to address the prevailing challenge of low
national T. Aman rice yield and the common farmer practice
of using over-aged seedlings. The study aimed to determine
the optimal seedling age and genotype combination for
maximizing both grain yield and seed quality. Three rice
varieties (BRRI dhan32, BRRI dhan62, and BRRI dhan80) were
evaluated across four transplanting ages (20, 25, 30, and 35
days) using a two-factor Randomized Complete Block Design
(RCBD). Results demonstrated that the variety BRRI dhan32
was statistically superior, yielding the highest grain (4.68
t/ha) and exhibiting the best seed germination (88.33%),
primarily due to its robust yield components, including a
greater number of effective tillers and filled seeds per
panicle. Seedlings transplanted at 30 days old (A3)
significantly outperformed other ages, promoting optimal
growth and development and resulting in a maximum yield of
4.83 t/ha and germination of 92.01%. Crucially, the
interaction between BRRI dhan32 and 30-day-old seedlings (V1A3)
produced the highest combined performance, recording an
exceptional grain yield of 5.12 t/ha, superior germination
(92.86%), and the highest vigor index (2152.49), largely
attributable to enhanced 1000-seed weight. This research
conclusively recommends cultivating BRRI dhan32 with
30-day-old seedlings as a practical and effective strategy
to significantly boost the productivity and quality of T.
Aman rice, thereby enhancing national food security in
subtropical environments.
Keywords: Seeding, Yield Quality, T. Aman,
Harvesting, Rice.
МОДЕЛИРАНЕ И АНАЛИЗ НА РАЗПРЕДЕЛЕНИЕТО НА ПОТОКА И МОЩНОСТТА НА АКТИВНАТА ЗОНА НА РЕАКТОР HTR-10
Мохамед А. Алзамли, Хешам Елкатиб
MODELING AND
ANALYSIS OF FLUX AND POWER DISTRIBUTION FOR HTR-10
REACTOR CORE
Mohamed A. Alzamly1,
Hesham Elkatib2
1Fuel Cycle Safety
Department, Nuclear and Radiological Safety Research
Center, Egyptian Atomic Energy Authority, Cairo,
Egypt
2Reactor Department, Nuclear
Research Center, Egyptian Atomic Energy Authority,
Cairo, Egypt
Abstract. MCNP6 computer code
is used to model HTR-10 core reactor. UO2
fuel is used. We predict the Flux and power distribution
for normal core loaded by UO2 fuel pebbles of
the reference HTR-10 reactor. The MCNP model consisted
of the reactor structure which included the graphite
reflector, the borated carbon bricks surrounding it and
the pebble-bed core. The results show an analogue
between the thermal neutron flux distribution and the
power distribution, where the thermal neutrons are
responsible for causing the fission, and hence power
generation. The thermal neutron flux and power
generation have its maximum value at the core center and
decreases as we move away from the center to core
boundary. The thermal flux is increased near the
reflector because the neutron reflector scatters back
(or reflects) into the core many neutrons that would
otherwise escape. The neutrons reflected back into the
core are available for chain reaction (reflector
savings).
Keywords: Pebble-bed,
HTR-10, Flux distribution, power distribution,
thorium-based fuel.
ИЗСЛЕДВАНЕ НА
ИНСТРУМЕНТА ЗА КРИСТАЛИ ALPHA OMEGA
WATER®: РЕЗУЛТАТИ И АНАЛИЗИ С FT-IR, EIS, NMR И DFT
Игнат Игнатов, Йордан
Маринов
Ignat Ignatov1, Yordan
G. Marinov2
2 Georgi Nadjakov Institute of Solid State Physics, Bulgarian Academy of Sciences, Sofia, Bulgaria
Abstract:
Alpha Omega Water® represents an
innovative approach within environmental engineering aimed
at improving the physicochemical properties of water as a
key natural resource. As a high-quality treated water
product, it is associated with processes that help
maintain cleaner, more environmentally friendly water
systems.
This study examines the properties of
Alpha Omega Water® using Fourier-transform infrared
spectroscopy (FT-IR), proton nuclear magnetic resonance
(NMR) spectroscopy, electrochemical impedance spectroscopy
(EIS), and quantum chemical calculations based on Density
Functional Theory (DFT). Treated water was compared with
untreated control samples to evaluate possible differences
in molecular organization and electrical behavior.
The results showed measurable
differences in spectroscopic characteristics, impedance
response, and modeled water-cluster parameters between
treated and control samples under the applied experimental
conditions.
These findings may be consistent with
differences in the local hydrogen-bond environment and the
associated physicochemical behavior of water.
These results indicate that Alpha Omega
Water® possesses properties relevant to processes that
improve the physicochemical characteristics of water,
thereby contributing to the maintenance of a cleaner, more
environmentally favorable water environment.
Keywords: Alpha Omega Water,
hydrogen bonds, water clusters, FT-IR, NMR, DFT, EIS
ВЪЗМОЖНОСТ ЗА
ИНТЕГРИРАНЕ НА IoT-БАЗИРАНИ
ПАРКИРАНИ
ЕЛЕКТРИЧЕСКИ СКУТЕРИ С ОБЩЕСТВЕН ТРАНСПОРТ: ПРИМЕР
ЗА СОФИЯ, БЪЛГАРИЯ
Цветан Илиев
Tsvetan Iliev
The Institute of Robotics, Bulgarian Academy of Science (IR-BAS), Sofia, Bulgaria
Abstract: Urban transport systems face increasing challenges related to congestion, emissions, and inefficient first- and last-mile connectivity. This study proposes a methodological framework for evaluating the integration of Internet of Things (IoT)-enabled docked electric scooter systems with urban public transport through a composite index combining travel time, emissions, and cost. A case study based on the transport network of Sofia, Bulgaria, compares a conventional public transport scenario with an integrated metro and shared e-scooter scenario. The results demonstrate that the integrated approach can reduce travel time by approximately 27% and transport-related emissions by approximately 29%, while providing improved overall mobility performance despite slightly higher direct user cost. The proposed framework offers a simple and adaptable methodology for evaluating integrated micromobility solutions in sustainable urban transport systems.
Keywords: micromobility, electric scooters, urban mobility, public transport integration, IoT, sustainable transport
IN VITRO АНТИМИКРОБНА АКТИВНОСТ НА СЪСТАВ НА БАЗАТА НА L-ЯБЪЛЧЕНА КИСЕЛИНА
Теодора П. Попова, Мила Д. Калева, Фабио Хютер, Александър Игнатов, Игнат Игнатов
IN VITRO ANTIMICROBIAL ACTIVITY OF L-MALIC ACID-BASED COMPOSITION
Teodora P. Popova1*, Mila D. Kaleva2, Fabio Huether3, Alexander I. Ignatov4, Ignat Ignatov4
1Faculty of Veterinary Medicine, University of Forestry, 10 Kl. Ohridski Blvd., 1756 Sofia, Bulgaria
2The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, 1113 Sofia, Bulgaria
3EVODROP AG, 8306 Brüttisellen, Switzerland
4Scientific Research Center of Medical Biophysics (SRCMB), 1111 Sofia, Bulgaria
Email of corresponding author: tpopova@ltu.bg
Abstract. The increasing prevalence of antimicrobial resistance has intensified the search for safe and effective alternatives to conventional antimicrobial agents, including natural compounds. L-malic acid, a naturally occurring in fruits and plant tissues, has attracted interest in this respect. The present study evaluated the in vitro antimicrobial activity of a formulation containing L-malic acid against reference strains of Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Candida albicans using a suspension assay. The tested formulation comprised 60% (w/w) L-malic acid, 30% (w/w) starch, and 10% (w/w) organosilica, obtained from product IONSIEVE MALOX®. The formulation was evaluated at nominal L-malic acid concentrations of 1, 2, and 3 mg·L-1 and exposure times of 1, 4, and 24 h using final inoculum levels of 5×10² or 1×10² CFU/mL. Under the tested conditions, the formulation reduced the number of recoverable cells of all examined microorganisms in a concentration-, time-, and inoculum-dependent manner. At 3 mg·L-1, no recoverable E. coli cells were detected after 1 h at 5×10² CFU/mL, whereas C. albicans reached undetectable levels after 4 h and P. aeruginosa and S. aureus after 24 h. At 1×10² CFU/mL no recoverable C. albicans cells were detected after 1 h, while in the other tested microorganisms - after 4 h. The formulations at 1 and 2 mg·L-1 also reduced recoverable counts of all tested strains, although with weaker early effects. These findings indicate that, under in vitro suspension-test conditions, L-malic acid exhibited significant antimicrobial activity against the tested bacterial and yeast strains and merit further investigation under application-relevant conditions.
Keywords: L-malic acid, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans, antimicrobial activity