Articles
http://nur.nu.edu.kz:80/handle/123456789/2689
2024-03-28T17:22:56ZEFFECTIVENESS OF BIO-WASTE-DERIVED CARBON DOPING ON DE-ICING PERFORMANCE OF AN ELECTRICALLY RESISTANT CONCRETE
http://nur.nu.edu.kz:80/handle/123456789/7010
EFFECTIVENESS OF BIO-WASTE-DERIVED CARBON DOPING ON DE-ICING PERFORMANCE OF AN ELECTRICALLY RESISTANT CONCRETE
Bakbolat, Baglan; Daulbayev, Chingis; Sultanov, Fail; Taurbekov, Azamat; Tolynbekov, Aidos; Yeleuov, Mukhtar; Korobeinyk, Alina V.; Mansurov, Zulkhair
This paper proposes a modified carbon-based concrete filler composition, which can potentially be used as a self-de-icing pavement. Carbon fibers (CNFs), graphene-like porous carbon (GLC), and a CNF/GLC composite were developed to reinforce concrete with the aim to improve its electrical conductivity and mechanical properties. The effect of the CNF and GLC loadings on the electrical conductivity of the filled concrete was evaluated in a climatic chamber at temperatures simulating water-freezing conditions on a concrete road. The results show that even a negligible loading (0.2 wt.%) of concrete with CNF/GLC results in a dramatic decrease in its resistance when compared to the same loadings for CNF and GLC added separately. Depending on the number of fillers, the temperature of the modified concrete samples reached up to +19.8 °C at low voltage (10 V) at −10 °C, demonstrating the perspective of their heat output for anti-icing applications. Additionally, this study shows that adding 2.0 wt.% of the CNF/GLC composite to the concrete improves its compressive strength by 33.93% compared to the unmodified concrete.
2022-01-01T00:00:00ZSUPERHYDROPHOBIC SIO2/TRIMETHYLCHLOROSILANE COATING FOR SELF-CLEANING APPLICATION OF CONSTRUCTION MATERIALS
http://nur.nu.edu.kz:80/handle/123456789/7009
SUPERHYDROPHOBIC SIO2/TRIMETHYLCHLOROSILANE COATING FOR SELF-CLEANING APPLICATION OF CONSTRUCTION MATERIALS
Kurbanova, Aliya; Myrzakhmetova, Nurbala; Akimbayeva, Nazgul; Kishibayev, Kazhmukhan; Nurbekova, Marzhan; Kanagat, Yernar; Tursynova, Arailym; Zhunussova, Tomiris; Seralin, Aidar; Kudaibergenova, Rabiga; Toktarbay, Zhexenbek; Toktarbaiuly, Olzat
This study has demonstrated, for the first time, the potential application of coatings to protect bricks or architectures against detrimental atmospheric effects via a self-cleaning approach. In this research, a facile fabrication method was developed to produce amorphous SiO2 particles and their hierarchical structures via applying trimethylchlorosilane (TMCS). They were fully characterized by various surface analytic tools, including a goniometer, SEM, AFM, zeta sizer, and a spectroscopic technique (FTIR), and then applied as super hydrophobic coatings on glass and sand. The characterization results revealed that the SiO2 particles are amorphous, quasi-spherical particles with an average diameter of 250–300 nm, and the hierarchical structures in the film were assembled from building blocks of SiO2 and TMCS. The wettability of the films can be controlled by changing the pH of the SiO2/TCMS dispersion. A super hydrophobic surface with a water contact angle of 165° ± 1° was achieved at the isoelectric point of the films. The obtained translucent super hydrophobic SiO2/TMCS coatings show good self-cleaning performances for glass and sand as construction materials. This study indicated that the superhydrophobic coatings may have potential applications in the protection of buildings and construction architectures in the future.
2022-01-01T00:00:00ZBIODICA: A COMPUTATIONAL ENVIRONMENT FOR INDEPENDENT COMPONENT ANALYSIS OF OMICS DATA
http://nur.nu.edu.kz:80/handle/123456789/6997
BIODICA: A COMPUTATIONAL ENVIRONMENT FOR INDEPENDENT COMPONENT ANALYSIS OF OMICS DATA
Captier, Nicolas; Merlevede, Jane; Molkenov, Askhat; Seisenova, Ainur; Zhubanchaliyev, Altynbek; Nazarov, Petr V; Barillot, Emmanuel; Kairov, Ulykbek; Zinovyev, Andrei
We developed BIODICA, an integrated computational environment for application of independent component analysis (ICA) to bulk and single-cell molecular profiles, interpretation of the results in terms of biological functions and correlation with metadata. The computational core is the novel Python package stabilized-ica which provides interface to several ICA algorithms, a stabilization procedure, meta-analysis and component interpretation tools. BIODICA is equipped with a user-friendly graphical user interface, allowing non-experienced users to perform the ICA-based omics data analysis. The results are provided in interactive ways, thus facilitating communication with biology experts.
2022-01-01T00:00:00ZPHOTO CROSSLINKED LIGNIN/PAN ELECTROSPUN SEPARATOR FOR SAFE LITHIUM ION BATTERIES
http://nur.nu.edu.kz:80/handle/123456789/6970
PHOTO CROSSLINKED LIGNIN/PAN ELECTROSPUN SEPARATOR FOR SAFE LITHIUM ION BATTERIES
Yerkinbekova, Yerkezhan; Kalybekkyzy, Sandugash; Tolganbek, Nurbol; Kahraman, Memet Vezir; Bakenov, Zhumabay; Mentbayeva, Almagul
A novel crosslinked electrospun nanofibrous membrane with maleated lignin (ML) and poly(acrylonitrile) (PAN) is presented as a separator for lithium-ion batteries (LIBs). Alkali lignin was treated with an esterification agent of maleic anhydride, resulting in a substantial hydroxyl group conversion to enhance the reactivity and mechanical properties of the final nanofiber membranes. The maleated lignin (ML) was subsequently mixed with UV-curable formulations (up to 30% wt) containing polyethylene glycol diacrylate (PEGDA), hydrolyzed 3-(Trimethoxysilyl)propyl methacrylate (HMEMO) as crosslinkers, and poly(acrylonitrile) (PAN) as a precursor polymer. UV-electrospinning was used to fabricate PAN/ML/HMEMO/PEGDA (PMHP) crosslinked membranes. PMHP membranes made of electrospun nanofibers feature a three-dimensional (3D) porous structure with interconnected voids between the fibers. The mechanical strength of PMHP membranes with a thickness of 25 µm was enhanced by the variation of the cross-linkable formulations. The cell assembled with PMHP2 membrane (20 wt% of ML) showed the maximum ionic conductivity value of 2.79*10−3 S cm−1, which is significantly higher than that of the same cell with the liquid electrolyte and commercial Celgard 2400 (6.5*10−4 S cm−1). The enhanced LIB efficiency with PMHP2 membrane can be attributed to its high porosity, which allows better electrolyte uptake and demonstrates higher ionic conductivity. As a result, the cell assembled with LiFePO4 cathode, Li metal anode, and PMHP2 membrane had a high initial discharge specific capacity of 147 mAh g−1 at 0.1 C and exhibited outstanding rate performance. Also, it effectively limits the formation of Li dendrites over 1000 h. PMHP separators have improved chemical and physical properties, including porosity, thermal, mechanical, and electrochemical characteristics, compared with the commercial ones.
2022-01-01T00:00:00ZSPUTNIK-V REACTOGENICITY AND IMMUNOGENICITY IN THE BLOOD AND MUCOSA: A PROSPECTIVE COHORT STUDY
http://nur.nu.edu.kz:80/handle/123456789/6963
SPUTNIK-V REACTOGENICITY AND IMMUNOGENICITY IN THE BLOOD AND MUCOSA: A PROSPECTIVE COHORT STUDY
Yegorov, Sergey; Kadyrova, Irina; Negmetzhanov, Baurzhan; Kolesnikova, Yevgeniya; Kolesnichenko, Svetlana; Korshukov, Ilya; Baiken, Yeldar; Matkarimov, Bakhyt; Miller, Matthew S.
Sputnik-V (Gam-COVID-Vac) is a heterologous, recombinant adenoviral (rAdv) vector-based, COVID-
19 vaccine now used in > 70 countries. Yet there is a shortage of data on this vaccine’s performance in
diverse populations. Here, we performed a prospective cohort study to assess the reactogenicity and
immunologic outcomes of Sputnik-V vaccination in Kazakhstan. COVID-19-free participants (n = 82 at
baseline) were followed at day 21 after Sputnik-V dose 1 (rAd5) and dose 2 (rAd26). Self-reported local
and systemic adverse events were captured using questionnaires. Blood and nasopharyngeal swabs
were collected to perform SARS-CoV-2 diagnostic and immunologic assays. We observed that most
of the reported adverse events were mild-to-moderate injection site or systemic reactions, no severe
or potentially life-threatening conditions were reported, and dose 1 appeared to be more reactogenic
than dose 2. The seroconversion rate was 97% post-dose 1, remaining the same post-dose 2. The
proportion of participants with detectable virus neutralization was 83% post-dose 1, increasing to
98% post-dose 2, with the largest relative increase observed in participants without prior COVID-
19 exposure. Dose 1 boosted nasal S-IgG and S-IgA, while the boosting effect of dose 2 on mucosal
S-IgG, but not S-IgA, was only observed in subjects without prior COVID-19. Systemically, vaccination
reduced serum levels of growth regulated oncogene (GRO), which correlated with an elevation
in blood platelet count. Overall, Sputnik-V dose 1 elicited both blood and mucosal SARS-CoV-2
immunity, while the immune boosting effect of dose 2 was minimal. Thus, adjustments to the current
vaccine dosing regimen are necessary to optimize immunization efficacy and cost-effectiveness. While
Sputnik-V reactogenicity is similar to that of other COVID-19 vaccines, the induced alterations to the
GRO/platelet axis warrant investigation of the vaccine’s effects on systemic immunology.
2022-01-01T00:00:00ZEXPERIMENTAL AND MODELING STUDIES OF SR2+ AND CS+ SORPTION ON CRYOGELS AND COMPARISON TO COMMERCIAL ADSORBENTS
http://nur.nu.edu.kz:80/handle/123456789/6950
EXPERIMENTAL AND MODELING STUDIES OF SR2+ AND CS+ SORPTION ON CRYOGELS AND COMPARISON TO COMMERCIAL ADSORBENTS
Baimenov, Alzhan; Montagnaro, Fabio; Inglezakis, Vassilis J.; Balsamo, Marco
In this work, two cryogels with the key monomers
methacrylic acid and 2-acrylamido-2-methyl-1-propansulfonic acid
(named AAC and SAC, respectively) with various functional
groups were used as adsorbents for the removal of cesium and
strontium ions from aqueous solutions. Kinetics, equilibrium, and
column studies were carried out including experiments in different
water matrices (ultrapure, tap, and river water) and comparison to
commercial adsorbents. AAC reached sorption capacity of 362 mg
g−1 for Cs+ and 209 mg g−1 for Sr2+, whereas SAC polymer showed
maximum removal capacities of 259 and 211 mg g−1 for Cs+ and
Sr2+, respectively. The five cycles of adsorption/desorption
experiments showed a maximum of 8% loss of effectiveness for
both cryogels. Batch kinetics adsorption data were modeled by using a rigorous diffusional model coupled to a novel fractal-like
expression for variable surface diffusivity. The model revealed that the surface diffusivity dependence on time is nonmonotonic, with
the occurrence of a maximum. Also, both fluid film and intraparticle transport resistances were shown to be important, with the
internal one being more influential. The cryogels and two commercial materials (ion-exchange resin and zeolite) were tested for the
removal of Cs+ and Sr2+ in ultrapure, tap, and river water; the results showed that the cryogels exhibit competitive effectiveness.
2022-01-01T00:00:00Z