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CaZnO-based nanoghosts for the detection of ssDNA, pCRISPR and recombinant SARS-CoV-2 spike antigen and targeted delivery of doxorubicin
- Navid Rabiee
- Omid Akhavan
- Yousef Fatahi
- Amir Mohammad Ghadiri
- Mahsa Kiani
- Pooyan Makvandi
- Mohammad Rabiee
- Mohammad Hossein Nicknam
- Mohammad Saeb
- Rajender S. Varma
- Milad Ashrafizadeh
- Ehsan Nazarzadeh Zare
- Esmaeel Sharifi
- Eder C. Lima
2022 CHEMOSPHERE
Overexpression of proteins/antigens and other gene-related sequences in the bodies could lead to significant mutations and refractory diseases. Detection and identification of assorted trace concentrations of such proteins/antigens and/or gene-related sequences remain challenging, affecting different pathogens and making viruses stronger. Correspondingly, coronavirus (SARS-CoV-2) mutations/alterations and spread could lead to overexpression of ssDNA and the related antigens in the population and brisk activity in gene-editing technologies in the treatment/detection may lead to the presence of pCRISPR in the blood. Therefore, the detection and evaluation of their trace concentrations are of critical importance. CaZnO-based nanoghosts (NGs) were synthesized with the assistance of a high-gravity technique at a 1,800 MHz field, capitalizing on the use of Rosmarinus officinalis leaf extract as the templating agent. A complete chemical, physical and biological investigation revealed that the synthesized NGs presented similar morphological features to the mesenchymal stem cells (MSCs), resulting in excellent biocompatibility, interaction with ssDNA- and/or pCRISPR-surface, through various chemical and physical mechanisms. This comprise the unprecedented synthesis of a fully inorganic nanostructure with behavior that is similar to MSCs. Furthermore, the endowed exceptional ability of inorganic NGs for detective sensing/folding of ssDNA and pCRISPR and recombinant SARS-CoV-2 spike antigen (RSCSA), along with in-situ hydrogen peroxide detection on the HEK-293 and HeLa cell lines, was discerned. On average, they displayed a high drug loading capacity of 55%, and the acceptable internalizations inside the HT-29 cell lines affirmed the anticipated MSCs-like behavior of these inorganic-NGs.
Ce site dilution effects in the antiferromagnetic heavy fermion CeIn3
- Soonbeom Seo
- In Cheol Kim
- Han-oh Lee
- Tomasz Klimczuk
- Chan-Koo Park
- Tuson Park
2022 Physical Review Materials
La-doped intermetallic single crystals of Ce1−xLaxIn3 were synthesized via an In self-flux method throughout the entire range (x = 0–1). The prototypical heavy-fermion compound CeIn3 shows an antiferromagnetic phase transition at 10.1 K and becomes superconducting near a critical pressure where TN is completely suppressed. As the La concentration increases, Ce moments are diluted, and the lattice constant increases linearly, satisfying Vegard’s law. The electrical resistivity of the high-quality single crystals of Ce1−xLaxIn3 shows a gradual suppression of TN to 0 K at approximately xc = 0.65. The sign of the slope of the low-temperature resistivity vs temperature changes from positive to negative in the vicinity of the critical concentration xc, indicating a change in the Kondo ground states from the Kondo lattice to the Kondo impurity state. In the Kondo lattice state (x < xc ), the coherence temperature (=50K) assigned as the peak in the resistivity is almost independent of the La concentration. In the Kondo impurity state (x > xc ), on the other hand, a kinklike feature in the resistivity appears at ∼50K and persists up to x = 0.97, indicating a change of the Kondo scattering owing to the crystalline electric field effects. These results suggest that the critical concentration is closely connected to the emergence of the Kondo coherence state.
Cellular network quality evaluation at a university campus on the eve of 5G
- Przemysław Falkowski-Gilski
- Tadeus Uhl
2022 Pełny tekst Zeszyty Naukowe Akademii Morskiej w Szczecinie
Thanks to the availability of mobile devices and the spread of broadband access around the world, the number of network users continues to grow. This has raised user awareness when it comes to the quality of content they consume. Many service providers and operators focus on monitoring QoN (Quality of Network) and QoS (Quality of Service) parameters, particularly those influenced by bandwidth and latency. However, for most end-users, quality is understood as the subjective QoE (Quality of Experience), a mixture of several individual factors. This paper presents a QoN evaluation, carried out under real-time operating conditions at a university campus, considering the overall performance of the cellular network. The study involved 50 mobile devices, i.e., smartphones, used by students during their typical activity throughout a week. The results were gathered on the eve of 5G, using a custom-built Android application. This application enabled the acquisition of valuable data about the wireless link, including download and upload speed, latency (pink), the ID of the serving base station, and type of cellular connection. This approach can be used to detect the strengths and weaknesses of back-end networks.
Cellulose and its derivatives, coffee grounds, and cross-linked, β-cyclodextrin in the race for the highest sorption capacity of cationic dyes in accordance with the principles of sustainable development
- Anna Skwierawska
- Monika Bliźniewska
- Kinga Muza
- Agnieszka Nowak
- Dominika Nowacka
- Muhammad Khan
- Shan E Zehra Syeda
- Bogusława Łęska
- Bogusława Leska
2022 Pełny tekst JOURNAL OF HAZARDOUS MATERIALS
In this study, seven different materials were analyzed and includes coffee grounds (CG), two types of cellulose (CGC and CC), two types of modified cellulose (CT and CTCD), and cross-linked β-cyclodextrin (CD-1 and CD-2) were tested as adsorbents for the removal of dyes from the wastewater. The composition, morphology, and presence of functional groups in the obtained sorption materials were characterized by elemental analysis, SEM, TG/DTA, and FTIR spectroscopy. The sorption processes of the model contaminant, crystal violet (CV), were studied by kinetics and equilibrium models. The results showed, that using CTCD, the dye was adsorbed rapidly in 1 min and the slowest adsorption occurred in 20 min by CG. The time evolution was adjusted using two models, the pseudo-second-order model (CG and CGC) and the pseudo-first-order model in the rest adsorbents. According to the Langmuir and Sips isotherm models, the maximum adsorption capacities were very high in each case ranging from 1092.24 to 1220.40 mg g-1. Moreover, the adsorption capacity of the near-natural materials remained even higher after five regeneration cycles. The regeneration is almost waste-free and the materials used can be decomposed during composting. In addition, almost complete removal of cationic dyes was observed during the treatment of real wastewater samples.
Centrum aktywności / Lubawa
- Joanna Kabrońska
2022 Pełny tekst Architektura-Murator
Stworzenie przestrzeni publicznej wpływającej pozytywnie na społeczne relacje – poczucie sprawczości, odpowiedzialności oraz współuczestnictwa jednostek w życiu lokalnej społeczności – wymaga wzięcia pod uwagę nie tylko obecnych oczekiwań jej użytkowników. Taka przestrzeń powinna również przewidywać i kształtować przyszłe aspiracje wspólnoty. Otwarte w 2020 roku Centrum Aktywności Społecznej zaprojektowane przez Autorską Pracownię Architektury CAD stanowi odpowiedź na istniejące w regionie problemy wykluczenia społecznego.
CENTRUM GMINNE JAK ŻADNE INNE . Trąbki Wielkie
- Agnieszka Kurkowska
- Alicja Karaś
- Tomasz Szymański
2022
Wystawa zaprezentowana w Gmachu Głównym Politechniki Gdańskiej oparta jest o prace studentów zrealizowane w ramach przedmiotu “Projektowanie architektoniczne 5” i zgłoszone do konkursu pt. NOWE CENTRUM GMINNE. Koncepcja rozwoju Trąbek Wielkich. prowadzący: mgr inż. arch. Alicja Karaś, dr inż. arch. Agnieszka Kurkowska dr inż. arch. Tomasz Szymański
Centrum kompetencji energetyki odnawialnej w przyjaznej mieszkańcom nowoczesnej dzielnicy przemysłowo-logistycznej
- Karolina Krośnicka
- Katarzyna Zielonko-Jung
2022
Rozdział zawiera opis celów i przyczyn podjęcia tematu projektu Centrum kompetencji energetyki odnawialnej i wyjaśnia społeczne konsekwencje planowanej w mieście Rumia inwestycji.
CERTIFICATION SYSTEM AS A TOOL FOR IMPROVING THE SAFETY AND SUSTAINABILITY OF SCHOOL-RELATED TRAVELS
- Romanika Okraszewska
- Tomasz Mackun
2022 Pełny tekst Journal of Civil Engineering and Transport
Despite the well-established physical, social, emotional, cognitive, and spatial benefits of active and autonomous school commuting of children and adolescents', many are driven by car. Pilot surveys and field research held in 2019 in 10 Gdansk primary schools confirmed this trend. The article presents a certification system for schools, commissioned by the City of Gdańsk, which is an element of a systemic solution shaping patterns of transport behavior in school trips. The essence of the proposed approach is motivating and supporting schools by government to create conditions conducive to independent and active travel of children and adolescents. An important element of the certification process is the assessment stage in accordance with the set of criteria adopted and grouped into six areas concerning: children transport behavior, infrastructure and traffic organization in and around the school, mobility policy, road safety, promotion, and education. Groups of criteria were divided into basic and extended ones and assigned points in an assessment calculator. A minimum threshold of points has been set in each category to attract schools to take comprehensive action. The assessment calculator has been supplemented by catalogues of good practices describing possible actions that could be taken to meet a given criterion. The full certification process has not yet been completed in Gdańsk due to the coronavirus pandemic and the transition to remote learning. However, the first infrastructural improvements have already been made in the vicinity of schools.
Challenges and Possibilities of Deep Eutectic Solvent-Based Membranes
- Rene Cabezas
- Elsie Zurob
- Belén Gomez
- Gastón Merlet
- Andrea Plaza
- Claudio Araya-Lopez
- Julio Romero
- Felipe Olea
- Esteban Quijada-Maldonado
- Luis Pino-Soto
- Thais Gonzalez
- Roberto Castro-Muñoz
2022 INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
Deep eutectic solvents (DES) are a category of a new class of solvents that can overcome some of the main drawbacks of typical solvents and ionic liquids (ILs). DES have been widely investigated and applied by the research community in several applications since their invention. Over the past years, the use of DES has been directed to the production of new materials and items for new products and processes. This is the case for the implementation of DES in various fields of chemical engineering directed to separations. DES have been very recently initiated to be combined into membranes for membrane processes. In this regard, this Review timely elucidates the current progress in utilizing this new generation of solvents in membrane preparation. In this work, different techniques, methods, and strategies for incorporating DES into polymer membranes for different concepts of membranes according to the final application have been reviewed. Particular emphasis has been devoted to the most relevant development works and results. After the current literature was analyzed, the main challenges and possibilities of DES in membranes were declared.
Challenges in operating and testing loop heat pipes in 500–700 K temperature ranges
- Paweł Szymański
- Dariusz Mikielewicz
2022 Pełny tekst Archives of Thermodynamics
The potential applications of loop heat pipes (LHPs) are the nuclear power space systems, fuel cell thermal management systems, waste heat recovery systems, medium temperature electronic systems, medium temperature military systems, among others. Such applications usually operate in temperature ranges between 500–700 K, hence it is necessary to develop an LHP system that will meet this requirement. Such a thermal management device require to meet various technical problems and challenges currently existing in the development of LHP working in medium temperatures, including: (1) selection of appropriate working fluid; (2) selection of appropriate LHP construction material; (3) construction of suitable test rig capable of testing at elevated temperatures; (4) development of new testing methods. Currently, there are no proven working fluids that can be used in LHPs in medium temperature ranges. Water can be applicable only at temperatures up to 570 K. Caesium can be applicable at temperatures above 670 K. Organic fluids usually tend to generate non-condensable gasses and/or decompose at elevated temperatures and their viscosity dramatically increases. For halides, most of them are very reactive or toxic and their full property data are not available or the majority of the physical properties are predicted, also live tests and their environmental impact data are not adequate. As for casing/LHP construction material, there are no full chemical compatibility tables with most of the medium temperature working fluids and the reactivity of fluids significantly limits the potential materials. Also, testing such an LHP is an endeavour as the reactivity of medium temperature fluids and the use of obscure metals create new challenges. Altogether creates multiple challenges in the development, testing, handling and operating of LHP in the medium temperature range.
Changes in the Global Competitiveness Index 4.0 Methodology: The Improved Approach of Competitiveness Benchmarking
- Magdalena Olczyk
- Marta Kuc-Czarnecka
- Andrea Saltelli,
2022 Pełny tekst Journal of Competitiveness
The Global Competitiveness Index (GCI) developed by the World Economic Forum (WEF) is used as a standard for measuring a country’s competitiveness. However, in literature, the GCI has been accused of numerous methodological flaws. Consequently, in 2018, the WEF introduced significant methodological changes. This study aims to examine whether the methodological modifications in the GCI’s structure increase its ability to capture the real competitiveness of economies. In addition, the study considers whether the selection of weights of individual elements included in the GCI is optimal or could be improved. By employing a sensitivity-based analysis, we find that the change in methodology resulted in fewer pillars of marginal importance. In the case of the GCI 2017, there were four pillars, whereas in that of the GCI 4.0, there were only two pillars: product market and labor market. Furthermore, we reveal that the WEF weights do not reflect the measured importance of the variables. In the optimization process, numerous variables (primarily opinion-based indicators) were insignificant in explaining the GCI variance and could be eliminated from the set of diagnostic variables without affecting the index’s value. For instance, in the case of the GCI 4.0, 35 out of 103 variables could be eliminated. The new rankings obtained by weight optimization and reduction of the diagnostic variables demonstrated a strong positive correlation with the original rankings. This research contributes to the literature from both a theoretical perspective (indicating the most vital indicators in the GCI) and a practical standpoint (reducing the costs and time of obtaining redundant data).
Chapel at St. Joseph's Church in Gdańsk
- Aleksander Piwek
2022 Pełny tekst Architectus
The subject of this article is the chapel located in the former Gdańsk Carmelite monastery complex. The results of the architectural research carried out in it in 2014–2015 are presented. As a result, the time and purpose of the building’s construction were established. The original appearance and traces of later alterations were also recognised. The recesses found on the longitudinal walls, of similar dimensions, not reaching the floor, were considered to be the original decoration of the chapel. Other details, such as the original passage into the church and the west matroneum, also belonged to it. The wide cupboard recesses reaching to the floor were evidence of later changes, also linked to the function of the sacristy. Other changes include a major redesign of the interior at the beginning of the 20th century. This involved the construction of two stone pillars and the installation of vaults on top of them. Recent construction and restoration work has left exposed medieval details, some reconstructed in fragments or even as a whole. Traces of alterations considered secondary have been eliminated. The principle adopted allowed the medieval decoration of the chapel to be shown to a considerable extent for the first time in centuries. The building is one of the most interesting to be found in the city today.
Characterization of diatomaceous earth coated with nitrated asphaltenes as superior adsorbent for removal of VOCs from gas phase in fixed bed column
- Maksymilian Plata-Gryl
- Malwina Momotko
- Sławomir Makowiec
- Grzegorz Boczkaj
2022 Pełny tekst CHEMICAL ENGINEERING JOURNAL
Asphaltenes isolated from bitumen possess unusual adsorption characteristics that can be further enhanced by chemical modifications to promote interactions with VOCs’. Herein, nitrated asphaltenes are used as an active layer coated on a surface of a diatomaceous earth, in order to prepare an efficient adsorbent (AsfNitro). Breakthrough experiments with benzene, pyridine, and 1-nitropropane revealed significant increase in adsorption capacity, after deposition of nitrated asphaltenes, by 26, 12, and 8 times respectively. The adsorption capacity of AsfNitro for benzene per square meter of surface area is far more superior than for other adsorbents in use. Moreover, the AsfNitro exhibited excellent efficiency. For adsorption of 1-nitropropane and pyridine, almost 100% of the adsorbent’s bed was effectively used. Inverse gas chromatography measurements proved that nitrated asphaltenes were exclusively responsible for the adsorption properties, and the role of the diatomaceous earth was only to provide the surface area. Presented findings can be extended to other support materials and their inherent limitations for adsorption of VOCs can be overcome. Comparison of adsorption enthalpies demonstrated that common adsorbents e.g. activated carbons, cannot compete with AsfNitro in terms of sorbate-sorbent interactions. Additionally, contribution of chemisorption mechanism was recognized for AsfNitro, which indicate catalytic properties, and opens a new research field about asphaltenes’ novel practical applications. Application of asphaltenes in adsorption processes can be an effective procedure for risk mitigation of hazardous VOCs, accompanied by effective waste management and materials’ valorisation. Wasted adsorbent can be easily regenerated (without deterioration of surface properties), or blended in bitumen-aggregates mixes for road paving applications.
Checkpoints that regulate balanced biosynthesis of lipopolysaccharide and its essentiality in Escherichia coli
- Gracjana Klein-Raina
- Alicja Wieczorek
- Martyna Szuster
- Satish Raina
2022 Pełny tekst INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
The outer membrane (OM) of Gram-negative bacteria, such as Escherichia coli, is essential for their viability. Lipopolysaccharide (LPS) constitutes the major component of OM, providing the permeability barrier, and a tight balance exists between LPS and phospholipids amounts as both of these essential components use a common metabolic precursor. Hence, checkpoints are in place, right from the regulation of the first committed step in LPS biosynthesis mediated by LpxC through its turnover by FtsH and HslUV proteases in coordination with LPS assembly factors LapB and LapC. After the synthesis of LPS on the inner leaflet of the inner membrane (IM), LPS is flipped by the IM-located essential ATP-dependent transporter to the periplasmic face of IM, where it is picked up by the LPS transport complex spanning all three components of the cell en-velope for its delivery to OM. MsbA exerts its intrinsic hydrocarbon ruler function as another checkpoint to transport hexa-acylated LPS as compared to underacylated LPS. Additional checkpoints in LPS assembly are: LapB-assisted coupling of LPS synthesis and translocation; car-diolipin presence when LPS is underacylated; the recruitment of RfaH transcriptional factor en-suring the transcription of LPS core biosynthetic genes; and the regulated incorporation of non-stoichiometric modifications, controlled by the stress-responsive RpoE sigma factor, small RNAs and two-component systems.
Chemical analysis of low carbon content coals and their applications as dye adsorbent
- Mohd Azfar Shaida
- R.k. Dutta
- A.k. Sen
- S.s. Ram
- M. Sudarshan
- Mu. Naushad
- Grzegorz Boczkaj
- Md Sadique Nawab
2022 CHEMOSPHERE
Coal is primarily a fuel material but lately it has been utilized as an adsorbent for removing toxic metal ions. However, its usage for removing organic pollutants is not well studied. We report here a systematic study on the use of coal samples of varying carbon contents as adsorbents for removing Basic Blue 41 as a model cationic dye. The coal samples were collected from coal mines and were thoroughly characterized. The concentrations of carbon, hydrogen, oxygen, nitrogen and sulphur contents were measured by CHNS analyzer. The concentrations of aluminum, silicon, sulphur, titanium and iron were determined by EDXRF, which corresponded to silicon dioxide (quartz) and aluminium silicate (kaolinite) as the major mineral inclusions, corroborated by XRD results and micrographs showing elemental maps determined from SEM-EDAX. The coal samples with low carbon content revealed higher adsorption capacity (qe ∼ 8.0–9.3 mg/g) of Basic Blue dye at optimized adsorbent dose (2 mg/mL), pH 9 and contact time (120 min). The adsorption kinetic studies satisfied pseudo second order model and the intra-particle diffusion of the dye was evident. The dye adsorption followed Langmuir adsorption isotherm, and the qmax values ranged between 17 and 30 mg/g for low carbon content coal. The FT-IR, Brunauer-Emmett-Teller (BET) surface area and zeta potential results of the coal samples could explain the adsorption phenomenon of cationic dye. The kinetic and thermodynamic studies revealed that the adsorption of Basic Blue 41 dye was based on chemisorptions mechanism.
Chemical and biological evaluation of antioxidant activity of endogenous redox-active compounds compared to plant-derived exogenous antioxidants
- Patrycja Jakubek
2022 Pełny tekst
The research conducted so far has shown that endogenous antioxidants, despite being regarded as the first line of antioxidant defense, may not be sufficient to maintain redox homeostasis in cells exposed to oxidative stress. The results obtained in the doctoral dissertation show that endogenous redox-active compounds were moderate or weak scavengers of ABTS and DPPH radicals, while in cellular setting, their impact on the reducing capacity of HT29 cells was diversified. The results showed no significant correlation between the cellular antioxidant activity and electrochemical properties of tested compounds. Better compliance with biological activity was found for the kinetic parameter describing the velocity of neutralization of ABTS and DPPH radicals. Most of the tested redox-active compounds did not have significant impact on growth of HT29 cells. The inhibition of growth was observed solely in the case of high concentrations. Endogenous redox-active compounds did not protect DNA from fragmentation induced by oxidants in HT29 cells. The obtained results showed that endogenous redox-active compounds display weaker antioxidant activity compared to exogenous antioxidants. This research provided the systematic evidence that the maintenance of redox homeostasis, should the oxidative stress challenge occur, requires the support of exogenous dietary antioxidants.
Chemical characterization of wild populations of Brassica oleracea complex species (n=9) for the content of their bioactive compounds
- F. Branca
- M.c. Di Bella
- D. Arena
- A. Tribulato
- Barbara Kusznierewicz
- Karol Parchem
- Agnieszka Bartoszek-Pączkowska
2022
The wild species belonging to Brassica oleracea complex species (n=9) are widespread in the Mediterranean basin and represent the relative species of several vegetable crops, such as broccoli, cauliflower, kale, cabbage. They are characterized by the high level of bioactive compounds, such as glucosinolates (GLSs), known for their benefits for human health. Four accessions were evaluated: B. macrocarpa (BM) from Favignana (Trapani), B. trichocarpa (BTR) from Monte Gallo (Palermo), B. villosa (BV) from Monte Occhio (Palermo) and B. rupestris (BX) from Scalfani Bagni (Palermo). All these populations are widespread in the central-western Sicily inland areas and along the northwestern coast, in limestone cliffs or rarely sandstone, usually with exposure to the North or in shady positions, from sea level up to 1000 m. The accessions were stored in the genebank of Catania University. Characterization trial was performed in an open field in Catania (37°31’N, 15°4’E at 105 m a.s.l.) applying organic practices and with irrigation when required. Ten plants per populations were grown in open field in randomised blocks. The leaves were characterized by using the international descriptors IBPGR and UPOV, such as, area (m2), height (cm), longitude (cm) and colour as well as days to flower (g.d.). Leaves were freeze-dried and analysed to determine bioactive metabolites such as: phenolic compounds, glucosinolates. B. trichocarpa had the highest value of polyphenols 1.63 mg g‑1 dw while B. macrocarpa showed the lowest one (0.01 mg g‑1 dw). B. villosa showed highest level of glucoraphanin (35.2 μmol g‑1 dw). The results obtained showed high variability within the same population that present different morphometric traits and biochemical profile.
Chemical Composition of Atmospheric Air in Nemoral Scots Pine Forests and Submountainous Beech Forests: The Potential Region for the Introduction of Forest Therapy
- Tomasz Dudek
- Mariusz Marć
- Bożena Zabiegała
2022 Pełny tekst International Journal of Environmental Research and Public Health
Studies show that forests are one of the main recreational destinations. This can be explained by their beneficial effects on the health of their visitors, which can be attributed to compounds from the terpene group. The aim of this research was to determine the chemical composition of air in the interiors of Nemoral Scots pine forests and submountainous beech forests, with the determination of compounds of the terpene group. Samples of organic compounds present in the air were collected with the use of Tenax TA sorbent tubes. The process of separation, identification, and determination of the extracted organic compounds was carried out with the use of the gas chromatography technique integrated with a flame ionization detector. Additional identification of the extracted compounds was carried out with the use of GC coupled with mass spectrometry. The most abundant group of compounds was the aliphatic hydrocarbons, both saturated (linear and branched) and unsaturated (terpenes). Carbonyl compounds were also found in the collected samples, but they constituted no more than 10% of all compounds present on the chromatograms. The concentrations of terpenes and terpenoids in the forest atmosphere varied from 10 to 74 gm3, representing on average 33% of the total volatile organic compounds.
Chemical Pressure Tuning Magnetism from Pyrochlore to Triangular Lattices
- Ranuri S. Dissanayaka Mudiyanselage
- Tomasz Klimczuk
- Danrui Ni
- Robert J. Cava
- Weiwei Xie
2022 INORGANIC CHEMISTRY
Geometrically frustrated lattices combined with magnetism usually host quantum fluctuations that suppress magnetic orders and generate highly entangled ground states. Three-dimensionally (3D) frustrated magnets generally exist in the diamond and pyrochlore lattices, while two-dimensionally (2D) frustrated geometries contain Kagomé, triangular, and honeycomb lattices. In this work, we reported using chemical pressure to tune the magnetism of the pyrochlore lattice in LiYbSe2 into a triangular lattice by doping Ga or In. Li3−xGaxYb3Se6 and Li3−xInxYb3−yInySe6/Li3−xInxYb3−y□ySe6 crystallize in a trigonal α-NaFeO2 structure-type (space group R3̅m) and can be synthesized using either LiCl or Se flux. In Li3−xGaxYb3Se6, Ga3+ and Li+ are mixed, leaving Yb3+ on the triangular plane. Instead of just Li+ being replaced in Li3−xGaxYb3Se6, In3+ was observed in both the Li+ and Yb3+ layers in Li3−xInxYb3−yInySe6 depending on the reaction conditions. Dominant antiferromagnetic interactions are revealed by magnetic measurements in both Li3−xGaxYb3Se6 and Li3−xInxYb3−yInySe6/ Li3−xInxYb3−y□ySe6. However, no long-range magnetic order is detected in thermomagnetic measurements above 1.8 K due to geometrical frustration. Thus, Li3−xGaxYb3Se6, Li3−xInxYb3−yInySe6/Li3−xInxYb3−y□ySe6, and the LiYbSe2 previously discovered by our group provide an ideal platform to understand the complex structure−magnetism correlations from 3D to 2D frustrated lattices.
Chemometric Evaluation of WWTPs’ Wastewaters and Receiving Surface Waters in Bulgaria
- Veronika Mihaylova
- Galina Yotova
- Błażej Kudłak
- Tony Venelinov
- Tsakovski Stefan
2022 Pełny tekst Water
Wastewater treatment plant (WWTP) installations are designed and operated to reduce the quantity of pollutants emitted to surface waters receiving treated wastewaters. In this work, we used classical instrumental studies (to determine chemicals and parameters under obligations put with Directive 91/271/EEC), ecotoxicological tools (Sinapis alba root growth inhibition (SA-RG) and Heterocypris incongruens mortality (MORT) and growth inhibition (GRINH)) and multivariate statistical analysis to gain information on feature profiles of WWTPs’ effluents and the possible burden of surface water bodies receiving treated wastewaters in eleven locations of Bulgaria. Initial screening of results has shown that only phosphorus content exceeds the admissible level in 5 out 11 WWTP effluents, while As, Cr, Cu, Mn, and Zn show exceedance at several locations. The multivariate statistical analysis reveals the discriminating water quality parameters and outlines the ability of Heterocypris incongruens to evaluate the ecotoxicological potential of different groups of waters.