Scientific and Technical Bulletin, Series: Chemistry, Food Science and Engineering

ESTIMATING METHANE EMISSIONS FROM DIFFERENT LAND-USE TYPES IN THE URBAN AREA

2023-08-13T23:39:09+03:00

In the recent decades, greenhouse gas (GHG) emissions increased considerably; due to the remarkable
growth in anthropogenic activities. These gasses have potential warming effects on the atmosphere as long as they
accumulate in the atmosphere.
Methane (CH4) as a GHG has very high radiative forces, with a short lifetime of approximately 10 years.
Therefore, targeting CH4 emissions would bring immediate climate benefits in the short-term. Land-use changing policies
in the urban area decrease CH4 sinks and affect the urban contribution in CH4 budget. However, the uncertainty of CH4
emissions in the urban area is very high, so that estimating CH4 concentration is important to take appropriate mitigation
measures.
In our study, we estimated street-level CH4 concentrations in the following four urban areas: the city center (CC),
the central park (CP), a residential area (RA), and a commercial area (CA). An Enhanced Portable Fluxmeter device
with a precise measurement of 0.1 parts per million (ppm) was used to perform these CH4 estimations between 10:00
and 12:00 am (EEST), from 20-30 March.
The results showed that the CC and CA have an elevated contribution in CH4 concentration with more than 2.3
ppm. The RA recorded the least as hypothesize. Surprisingly, the CP which was supposed to have the least contribution
in CH4 concentration from the anthropogenic perspective, was estimated to have ascending records. These findings
demonstrate the remarkable contribution of the urban area in influencing CH4 concentration, and recommend further
CH4 investigation in the urban area and to identify its potential sources.

THE INVOLVEMENT AND ATTITUDE OF ROMANIAS IN PRO-ENVIRONMENTAL ACTIVITIES RELATED TO THE RISK OF MICROPLASTIC PARTICLES

2023-08-14T00:23:33+03:00

Microplastic particle (MPs) pollution is and will continue to be a real threat to the entire
planet. There is still no clear and complete information about these effects of MPs. In the research
area, the data held so far are enough to have reasons for concern about this global phenomenon that
shows an upward trend in global plastic production. The persistence in all four environmental
factors and the extreme diversity of MPs leads to high levels of uncertainty in hazard and exposure
estimates for this type of risk.hy do we produce plastic? Due to its durability, rigidity, and even abrasiveness. No technical and
efficient way could eliminate nano and microplastic from the environment, and thus people's
attitudes can play a significant role in reducing MPs emissions. Currently, few studies have
examined how individuals perceive MPs. Our research is based on how Romanians perceive risks
(MPs) and how such risk perception affects people's pro-environmental behavioral intention. The
entire study is based on a survey (questionnaire) of 405 people, from all over Romania. The
software used is SPSS and the questionnaire was sent online through different types of platforms.
GDPR rules were taken into account when preparing the questionnaire so that respondents are not
asked for their personal data. One of the questions in the questionnaire measures the following
statements on a scale from 1 to 7: "Dedicating time, money and effort to my activities is more
convenient for me than recycling plastic products"/ "Dedicating time, money and effort is more
convenient for me than replacing plastic items with ecological products. On the scale used, 1
represents - Categorically No / 7 - Categorically Yes. We made the delimitation by groups of
counties/regions so that we can see a result of the attitude of Romanians from Banat, Transylvania,
Maramures, Oltenia, Moldova, and Dobrogea, in relation to MPs.The results of our study show that in Romania, the recycling process is on an upward curve. We still do not have this culture of being friendly to the environment, as developed as in the West.

WEATHERING AND DETERIORATION OF CARBONATE STONES FROM HISTORICAL MONUMENTS: A REVIEW

2023-08-14T00:46:25+03:00

The degradation of historical monuments due to atmospheric and anthropogenic factors is a
frequently encountered phenomenon on all continents, being intensively investigated to understand the type
and degree of damage and to choose an appropriate restoration method. Based on extensive
bibliographic documentation, this study presents a comprehensive review of the physical, chemical,
and biological weathering processes induced by extrinsic factors (atmospheric, biological, and
anthropic) that lead to the deterioration of limestone and marble, the most common construction
materials found in historic buildings of humanity's architectural heritage.

PRELIMINARY STUDIES ABOUT SOME FACTORS INFLUENCING THE PROPERTIES OF OLEOGELS

2023-08-14T01:20:59+03:00

Nowadays, the use of oleogels offers several advantages in food products. They can mimic the
functionality of solid fats, providing structure, stability, and mouthfeel to various food formulations. By replacing solid
fats or hydrogenated oils with oleogels, manufacturers can reduce or eliminate trans fats and therefore produce
healthier food products. The present study focuses on the formulation of oleogels based on pumpkin seeds and rapeseed
oils and the use of beeswax or ethylcellulose as oleogelators. The preliminary results indicate that the pumpkin seeds
oil contributes to the formation of oleogels with higher consistency. Furthermore, the mechanical properties of oleogels
can be manipulated, by adjusting some parameters, such as the type of oil and the kind and concentration of the
oleogelator.

URBAN AQUEOUS SYSTEM AS A HOTSPOT FOR WATERATMOSPHERE EXCHANGE OF CH4

2023-08-14T01:26:03+03:00

Methane (CH4), a potent greenhouse gas, has negative radiative impacts on the atmosphere, reaching
up to 20 times compared with CO2. However, mitigating CH4 emissions from its sources, either natural or
anthropogenic, will reduce global warming consequences in the short run, given that CH4 has a short lifetime which
takes approximately a decade.
The urban aqueous system is part of the natural sources of CH4 in the urban area, which could be influenced by
microorganisms or increased human activities and the discharging of sewage water into the system.
Recent studies have stated that high organic matter in river sediments is the primary source for increased
production of CH4 in the river bed. However, the contribution of the urban aqueous system in CH4 annual fluxes is still
uncertain, so a research gap needs to be filled to understand further CH4 emissions from this system.
This study aims to detect CH4 content in the urban aqueous system and identify locations with high concentrations
to establish further investigation and determine the factors behind these concentrations.
In our study, the aqueous system is classified into three main categories: rivers, lakes, and ponds. Water samples
were collected from each of these sub-systems for estimating CH4 concentration. Samples from Somes River were
gathered from three segments: upstream, urban segment within the urban area, and downstream river. Moreover, samples
were also taken from lakes and ponds, considering spatial even distribution between sampling points.
Our samples were analyzed via head-space extraction method using Tunable Diode Laser Absorption
Spectroscopy (TDLAS), which precisely detects emissions up to 0.1 ppmv.
The results showed that water samples are oversaturated with CH4 concentration. In other words, the aqueous
system in the selected urban area represents an active hotspot for CH4 exchange from water into the atmosphere.
However, CH4 fluxes should be quantified to understand better the contribution of the urban aqueous system to
the CH4 budget and to take appropriate abatement measures for reducing these emissions.

CHEMICAL AND ANTIOXIDANT CAPACITY EVALUATION OF CENTAUREA JACEA EXTRACTS FROM PLANTS HARVESTED IN ARAD COUNTY, ROMANIA

2023-08-29T00:54:43+03:00

The phytochemical composition and biological activity of the plant extracts obtained in different solvents
(water, 70% ethanol, methanol, and diethyl ether) of the brown knapweed (Centaurea jacea L.) harvested in Romania
were obtained. The chemical composition of the extracts was determined by gas chromatography–mass spectrometry
analysis, by total phenolic and flavonoid content. The antioxidative potential was determined using ferric-reducing
antioxidant power (FRAP) and 2,2-dyphenyl-1-picrylhydrazyl (DPPH) scavenging methods. The methanolic extracts
revealed the highest antioxidant activity by FRAP and DPPH assays. This study revealed, once again, the importance of
the geographic and climate region of harvesting the plants used for biomedical applications.