CERASELA-IONELA CLEMINTE, “Gheorghe Asachi” Technical University of
Iaşi, “Cristofor Simionescu” Faculty of Chemical Engineering and
Environmental Protection, Iaşi, Romania GABRIELA LISA, “Gheorghe Asachi”
Technical University of Iaşi, “Cristofor Simionescu” Faculty of Chemical
Engineering and Environmental Protection, Iaşi, Romania,
gabriela.lisa@academic.tuiasi.ro
Abstract Sublimation is essential in chemical vapor deposition
(CVD), which is used to obtain thin material layers with applications in
semiconductor manufacturing, integrated circuits, or photovoltaic panels. By
optimizing the sublimation process, advanced materials with unique
properties can be obtained, revolutionizing fields such as electronics,
optics, and the aerospace industry. This study evaluates the influence of
temperature on the sublimation rate of naphthalene, frequently used as a
standard for studying the sublimation of aromatic hydrocarbons. For this
purpose, thermogravimetric analysis was applied under isothermal conditions,
using air as a carrier gas at temperatures of 40, 50, 60, and 70°C, with
different naphthalene layer thicknesses. The processing of thermogravimetric
curves allowed the determination of the mass loss percentage over time. The
sublimation rate was determined from the slope of these curves. The mass
loss rate of naphthalene followed zero-order kinetics. The study
demonstrated that isothermal thermogravimetric analysis provides a simple
method for determining kinetic parameters such as activation energy and
pre-exponential factor. Keywords: naphthalene, activation energy,
sublimation process, thermogravimetric analysis
LUCIAN PĂUNESCU, Daily Sourcing & Research SRL Bucharest, Romania,
lucianpaunescu16@gmail.com SORIN MIRCEA AXINTE, Daily Sourcing & Research SRL Bucharest, Romania;
Faculty of Applied Chemistry and Materials Science, National University of
Science and Technology “Politehnica” of Bucharest, Romania
Abstract A cellular glass aggregate with excellent heat insulation
properties and mechanical strength was designed and tested under conditions
of using unconventional microwave heating method. Sodium carbonate and
glycerol were utilized as simultaneous expanding agents. Green post-consumer
drinking glass was the predominant raw material in the mixture that
contained also kaolin and water glass. The optimal cellular glass product
had bulk density of 0.22 g·cm-3, heat conductivity of 0.062 W·m-1·K-1, and
compression strength of 6.9 MPa. The process energy efficiency was
excellent, the specific energy consumption being of 0.86 kWh·kg-1. The
originality of the work consists in choosing sodium carbonate as a foaming
agent together with glycerol and applying the own technique of mixed heating
(direct and indirect) with microwaves. Keywords: cellular glass,
microwave, glycerol, sodium carbonate, water glass
ANDREEA MONORANU, “Gheorghe Asachi” Technical University of Iaşi, Faculty
of Civil Engineering, Iași, Romania,
andreea.monoranu@student.tuiasi.ro GHEORGHE GUGIUMAN, “Gheorghe
Asachi” Technical University of Iaşi, Faculty of Civil Engineering, Iași,
Romania
Abstract In recent years, we hear more and more talk about pollution,
but especially about what it produces on the environment and implicitly on
people's health. All the states of the world, especially the developed ones,
are taking increasingly drastic measures to protect the environment. The
world's population has grown, its needs have grown, industry has tried to
keep up and has also developed to produce much more than 100 years ago, but
what do we do with the waste that results from the production process?
Industry is the biggest polluter today, waste from the metallurgical
industry has multiplied at an accelerated rate lately and has come to
represent a real problem. What would it be like if this problem disappeared
and also generated a significant economy of other materials? The article
shows how an industrial waste, steel slag, can be used in several fields,
especially in the construction of roads which is a big consumer of
resources, both reducing costs for them and solving the problem of occupying
ever larger spaces for slag storage. The study shows the amount of steel
slag produced by several countries in the world, how much of it is recycled
by each mentioned country and for what purpose, also giving some examples of
roads where this waste was used. Keywords: recycling, secondary product,
steel, crushed steel slag, road construction
LUCIAN PĂUNESCU, Daily Sourcing & Research SRL Bucharest, Romania, lucianpaunescu16@gmail.com SORIN MIRCEA AXINTE, Daily Sourcing & Research SRL Bucharest, Romania;
Faculty of Applied Chemistry and Materials Science, National University of
Science and Technology “Politehnica” of Bucharest, Romania
Abstract Fine-porosity glass foam was made from ground recycled waste
glass, using sodium hydroxide dissolved in distilled water, borax, and
titanium dioxide as additives. The dry mixture was heated for sintering at
810-825°C in a constructively and operationally adapted microwave oven,
heating times being varied between 27-60 min. The proportion of NaOH was
increased from 4.5 to 9%, so that the NaOH/borax ratio had values between
0.75-1.50. The experiments allowed the identification of the optimal
NaOH/borax ratio (1.25), so that the characteristics of the appropriate
specimen were: density of 0.14 g·cm-3, porosity of 89.6%, heat conductivity
of 0.042 W·m-1·K-1, and compression strength of 1.2 MPa. The pore size was
very low (between 40-80 µm), obtaining a structure with predominant
closed-porosity. Keywords: glass foam, fine-porosity, microwave, NaOH,
borax
ALFIAN FADHILAH ALMINDA, Department of Food Nanotechnology, Politeknik
AKA Bogor, Indonesia ANISSYA DWI KUSUMANINGRUM WIBISONO, Department of
Food Nanotechnology, Politeknik AKA Bogor, Indonesia AQILAH NURSAKHA,
Department of Food Nanotechnology, Politeknik AKA Bogor, Indonesia MITHA
YUSTIKA SYARI, Department of Food Nanotechnology, Politeknik AKA Bogor,
Indonesia SYIFA NUR’AFIYAH, Department of Food Nanotechnology,
Politeknik AKA Bogor, Indonesia YUDHISTIRA DIMAS NUGROHO, Department of
Food Nanotechnology, Politeknik AKA Bogor, Indonesia ZALFA JAWZA KAMILA,
Department of Food Nanotechnology, Politeknik AKA Bogor, Indonesia MOHAMMAD JIHAD MADIABU, Department of Analytical Chemistry, Politeknik AKA
Bogor, Indonesia ACHMAD NANDANG ROZIAFANTO, Department of Food
Nanotechnology, Politeknik AKA Bogor, Indonesia,
anandangr@yahoo.com
Abstract Heavy metal chromium (Cr) is one of the substances that can
cause water pollution. Although chromium is highly useful in various aspects
of life, including in the industrial sector, its excessive use also
generates waste that has the potential to damage the environment and pose
risks to human health. The analysis of chromium (Cr) presence in water was
conducted using the biosynthesis method of gold nanoparticles with Averrhoa
bilimbi as a bioreductant. Chromium, as one of the heavy metals, has many
industrial applications; however, its excessive use can pollute the
environment and endanger human health. The method used in this study is
colorimetry, which is known to be simple, effective, economical, and
accurate. The analysis results showed that gold nanoparticles synthesized
from Averrhoa bilimbi could detect chromium at a concentration of 10 mM
under optimal conditions at pH 5, temperature 75°C, and incubation time of 5
minutes. The synthesized gold nanoparticles proved to be selective and
sensitive in detecting the presence of chromium, thus offering a potential
solution for monitoring chromium pollution in aquatic environments.
Keywords: Chromium, Heavy metal, Bioreductant, Gold nanoparticles, Averrhoa
bilimbi, Sensitivity and selectivity, Biosynthesis
CLAUDIA COBZARU, “Gheorghe Asachi” Technical University of Iaşi,
“Cristofor Simionescu” Faculty of Chemical Engineering and Environmental
Protection, Iaşi, Romania OANA-NICOLETAȘCHIOPU, “Gheorghe Asachi”
Technical University of Iaşi, “Cristofor Simionescu” Faculty of Chemical
Engineering and Environmental Protection, Iaşi, Romania MĂLINA-MARIA
CERNĂTESCU, “Grigore T. Popa” University of Medicine and Pharmacy Iași,
Romania NICOLAE APOSTOLESCU, “Gheorghe Asachi” Technical University of
Iaşi, “Cristofor Simionescu” Faculty of Chemical Engineering and
Environmental Protection, Iaşi, Romania CORINA CERNĂTESCU, “Gheorghe
Asachi” Technical University of Iaşi, “Cristofor Simionescu” Faculty of
Chemical Engineering and Environmental Protection, Iaşi, Romania,
corina.cernatescu@academic.tuiasi.ro
Abstract The study focus on the formulation and microbiological
evaluation of a cosmetic cream with sea buckthorn extract and without
preservatives. The microbiological evaluation was carried out by determining
the total number of viable microorganisms (aerobic bacteria, yeasts and
filamentous fungi) and identifying pathogenic microorganisms such as:
Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and
Candida
albicans. The results obtained showed that from a microbiological point of
view, the product corresponds since after the incubation period no microbial
growth was observed. Keywords: cosmetic cream, sea buckthorn extract,
preservatives, microbiological evaluation
LOREDANA CHELEA, “Gheorghe Asachi” Technical University of Iaşi,
“Cristofor Simionescu” Faculty of Chemical Engineering and Environmental
Protection, Iaşi, Romania CONSTANȚA IBĂNESCU, “Gheorghe Asachi”
Technical University of Iaşi, “Cristofor Simionescu” Faculty of Chemical
Engineering and Environmental Protection, Iaşi, Romania MARICEL DANU,
“Gheorghe Asachi” Technical University of Iaşi, “Cristofor Simionescu”
Faculty of Chemical Engineering and Environmental Protection, Iaşi, Romania;
“Petru Poni” Institute of Macromolecular Chemistry of Iaşi, Romania,
maricel.danu@academic.tuiasi.ro
Abstract The delivery of pharmaceuticals to the skin is possible
using two methods: topical and transdermal. In the context of topical
administration, the drug is intended to act at the skin level, and it is
commonly employed in the treatment of skin diseases. Transdermal
administration achieves systemic delivery, when the skin is a barrier, not a
target. The objective of the present study is to characterize the
rheological behavior of drug carriers in topical administration. To this
aim, the rheological measurements of several commercial diclofenac
containing gels were performed. The present study demonstrates the
application of rheological measurements in the characterization of
pharmaceutical products. The viscoelastic properties could be successfully
correlated with the end-use properties, such as applicability, processing
behavior, storage, and thermal stability. Keywords: viscoelastic
properties, structural stability, gel strength, diclofenac, rheology