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Scientific data on the pharmacodynamics of dry extracts of Bupleurum aureum and Salsola collina L. based on the results of studying the antimicrobial effect and the similar effect of co-trimoxazole when they are used together have been supplemented. The investigated phytoextracts do not show antimicrobial properties, but they do not change the antimicrobial effect of co-trimoxazole when they are used in combination. The aim of the study was to experimentally investigate the antimicrobial effect of extracts of Bupleurum aureum and Salsola collina L. and establish the possible antagonistic effect of these extracts on the antimicrobial drug co-trimoxazole when used together. Materials and methods. The research was conducted in May 2016. Screening of the antimicrobial effect of extracts of Bupleurum aureum and Salsola collina L. and establishing of the possible antagonistic effect of these extracts on the antimicrobial drug co-trimoxazole when they are used together was carried out in the laboratory of the Department of Microbiology of the National Pharmaceutical University, which has a certificate of attestation 045/14 dated 28.10.2014. For determination of antimicrobial activity, the agar diffusion method ("well" method), which is based on the ability of medicinal substances to penetrate the agar layer, was used. A set of reference strains of microorganisms was used: S. aureus ATCC 6538, E. coli ATCC 8739, P. aeruginosa ATCC 9027, B. subtilis ATCC 6633, C. albicans ATCC 10231. Petri dishes were filled with two layers of solid nutrient medium. The lower layer - 10 ml of melted "cold" AGV agar (medium No. 3), the upper layer - nutrient medium for the corresponding test strain. After cooling the lower layer of agar, three thin-walled steel cylinders (inner diameter - 6.0±0.1 mm, height - 10.0±0.1 mm) were placed on it at an equal distance from each other and from the edge of the cup. The top layer was poured around the cylinders - 13.5 ml of agar, melted and cooled to 45-48°С, mixed with the seed dose of the test microorganism (1.5 ml of microbial suspension, the concentration corresponding to the type of microorganism). After cooling the upper layer of agar, the cylinders were removed with sterile tweezers and 0.25-0.3 ml of the studied drug was added to the resulting wells. The results were recorded after 24 h by measuring the zone of growth inhibition, including the diameter of the wells. Measurements were made with an accuracy of 1 mm, while focusing on the complete absence of visible growth. The obtained data were analyzed using the methods of variational statistics. The significance level is p

The aim. The study represents a continuation of the previous one, and provide various aspects related to the use of perfumery, which can be characterized by certain associations with the education level of Ukrainian consumers. Factors that have direct or indirect biological and medical significance and, accordingly, may have a potential impact on the safety of the perfume products use by humans, were selected for the analysis. Materials and methods. The analysis included information about 124 individuals living in Ukraine. The respondents answered the questions of the questionnaire developed regarding some aspects of the perfumery use. The Pearson chi-squared (χ2) test was used to analyze the relationships between qualitative characteristics. Results and discussion. Most of the studied aspects related to the perfumes use demonstrate associations, caused by the dependence of the education level on age. The analysis revealed that individuals with any education most often (about half of the cases or more) choose a perfume based on its scent. The study showed that the majority of respondents believe that the price of a perfume depends on a combination of factors, namely the composition of the products, the brand and the cost of the packaging. More than 80 % of people, regardless of the education level, believe that the persistence of a perfume is definitely a sign of quality. The most common opinion among people of all education levels was that non-original perfumes can have a more negative effect on people's health than original products. The "lipstick effect" in relation to perfume products (demand for items of "affordable luxury" in times of economic crises and wars) was observed. Conclusions. The study supplemented the previously found associations of age and some biological and behavioral aspects of perfume use among the population of Ukraine with data on the presence or absence of such associations in relation to the education level

The aim. The study encompassed some aspects related to perfumes use, which can potentially influence the individual perfume choice, in particular, among different age groups of the Ukrainian population. Factors related to perfumes choice, the state of awareness of respondents regarding quality, safety, and existing stereotypes regarding the characteristics of perfumes and potential harmful effects on the human body were investigated. Materials and methods. The analysis was performed on a sample of 124 residents of Ukraine. Respondents, who were randomly selected, were offered a questionnaire, developed by us, which included 15 items on the demographic characteristics of the subjects and questions related to the perfume use of and stereotypes about them. The Pearson chi-squared (χ2) test was used to analyze the relationships between qualitative characteristics. Results and discussion. About 98 % of surveyed persons in Ukraine use perfumery. Associations were found between age and the probability of purchase by the study participants of non-original perfume products and awareness of the safety of various perfume products. It has been established, that the determining factors when choosing a perfume is a certain scent, while the brand is given secondary importance. An increase in the effect of the brand in older age groups of the population has been demonstrated. Behavioral features of perfume use have been established: in younger women, it is associated with increased self-esteem and the influence of social networks, with age, the focus shifts to the desire for a positive effect on the mood from the use of a certain fragrance. However, in all age groups, the main purpose of perfume using was to improve the emotional state. Middle-aged women are more democratic in choosing perfumery with a specific gender orientation. Conclusions. For the first time in Ukraine, a pilot study was conducted to find possible associations between some biological, behavioral and demographic characteristics and the perfume use. Such factors as age and education level are promising for further analysis of the selected issues

Aim:the aim of the research is a pharmacological study of the original extracts of corn silk. Materials and methods.The object of the study were 4 original extracts of corn silk, obtained by extraction with water and ethanol of different concentrations, namely: aqueous extract of corn silk (ACSE), extract of corn silk, extracted with ethanol 30 % (ECSE 30 %) , extract of corn silk, extracted with ethanol 50 % (ЕCSЕ 50 %), extract of corn silk, extracted with ethanol 70 % (ЕCSЕ 70 %). A screening study of the antioxidant properties of corn silk extracts was carried out in vitro using models of spontaneous and ascorbate-induced lipid peroxidation (LPO) in rat liver homogenate. Results.As can be seen from the given data, ECSE 50 % at a dose of 20 mg/kg showed a pronounced protective effect on the hepatotoxicity of TСM. Its use led to a probable restoration of the bile-forming function of the liver against the background of tetrachloromethane hepatitis: in response to an increase in the cholesterol content (by 43 %, p Conclusions.Biologically active substances of corn silk affect not only the diffusion and filtration processes of the liver parenchyma, but also the biosynthesis and transport of its organic components, that is, they affect the bile-forming function

Most of the previous research on recycled concrete aggregates (RCA) has focused on coarse RCA (CRCA), while much less has been accomplished on the use of fine RCA particles (FRCA). Furthermore, most RCA research disregards its unique microstructure, and thus the inferior performance of concrete incorporating RCA is often reported in the fresh and hardened states. To improve the overall behaviour of RCA concrete advanced mix design techniques such as equivalent volume (EV) or particle packing models (PPMs) may be used. However, the efficiency of these procedures to proportion eco-efficient FRCA concrete still requires further investigation. This work evaluates the overall fresh (i.e., slump and rheological characterization) and hardened states (i.e., non-destructive tests, compressive strength and microscopy) performance of sustainable FRCA mixtures proportioned through distinct techniques (i.e., direct replacement, EV and PPMs) and incorporating different types of aggregates (i.e., natural and manufactured sand) and manufacturing processes (i.e., crusher fines and fully ground). Results demonstrate that the aggregate type and crushing process may influence the FRCA particles’ features. Yet, the use of advanced mix design techniques, particularly PPMs, may provide FRCA mixes with quite suitable performance in the fresh (i.e., 49% lower yield stress) and hardened states (i.e., 53% higher compressive strength) along with a low carbon footprint.

The pressure to use sustainable materials and adopt practices reducing the carbon footprint of the construction industry has risen. Such materials include recycled concrete aggregates (RCA) made from waste concrete. However, concrete made with RCA often presents poor fresh and hardened properties along with a decrease in its durability performance, especially when using its fine fraction (i.e., FRCA). Most studies involving FRCA use direct replacement methods (DRM) to proportion concrete although other techniques are available such as the Equivalent Volume (EV) and Particle Packing Models (PPMs); yet their impact on the durability performance, especially its performance against freezing and thawing (F/T), remains unknown. This work, therefore, appraises the F/T resistance of FRCA mixtures proportioned through various mix proportioning techniques (i.e., DRM, EV and PPMs), produced with distinct crushing processes (i.e., crusher’s fines vs. finely ground). The results show that the mix design technique has a significant influence on the FRCA mixture’s F/T resistance where PPM-proportioned mixtures demonstrate the best overall performance, exceeding the specified requirements while DRM-proportioned mixtures failed F/T resistance requirements. Moreover, the crushing process plays an important role in the recycled mixtures’ cracking behavior under F/T cycles, where less processing leads to fewer cracks while remaining the most sustainable option overall.

The research results of the effect of essential oils on the human short-term image and numerical memory have been described. The study involved 79 secondary school students (34 boys and 45 girls) aged 13 to 17 years, residents of the Ukrainian metropolis. Participants were divided into three groups: the control group, ‘‘Lavender” group, in which the lavender essential oil was sprayed, and ‘‘Rosemary” group, in which the rosemary essential oil was sprayed. The statistically significant differences in productivity of the short-term memory of the participants of different groups have been found. Therefore, the essential oils of rosemary and lavender have significantly increased the image memory compared to the control. Inhalation of the rosemary essential oil increased the memorization of numbers, and inhalation of the lavender essential oil weakened this process.Keywords: Lavender essential oil, Rosemary essential oil, Short-term memory, Ukraine

The research results of the effect of essential oil of rosemary on the human short-term image and numerical memory have been described. The study involved 53 secondary school students (24 boys and 29 girls) aged 13–15 years, residents of the Ukrainian metropolis. Participants were divided into the control group and “Rosemary” group, in which the rosemary essential oil was sprayed. The statistically significant differences in productivity of the short-term memory of the participants of these two groups have been found, while sex differences in uniform groups were absent. Therefore, the essential oil of rosemary has significantly increased the image memory compared to the control. Inhalation of the rosemary essential oil increased the memorization of numbers as well.

In this study a ceiling tile (CT) was selected as a sorptive passive panel, and the effect of environmental conditions on its formaldehyde removal efficiency was evaluated. Experiments were performed in a 0.4 m3 chamber with the air flow rate of 0.2 m3 h−1, the air exchange rate of the 0.5 h−1, and the loading ratio of 0.23m2m-3. The range of temperature humidity levels varied between 21 °C ± 2 °C–26 °C ± 2 °C, and 30% ± 5%–75% ± 5%, respectively, to simulate the indoor conditions for Canadian homes during most months of the year. Results demonstrated formaldehyde removal efficiency between 40% and 75% depending on the applied environmental conditions. GC/MS and HPLC trace analyses revealed that only very low concentrations of by-products were formed. The by-product formation increased slightly when exposing the ceiling tile to relatively high relative humidity (RH = 75%) and temperature (T = 26 °C). Given a loading factor of only 0.23 m2 m−3in our test chamber, which in most scenarios underestimates the loading factor in real settings, our findings suggest that ceiling tiles used as passive removal panels have the potential to lower formaldehyde concentrations under the Health Canada's guideline for residential settings under real-life conditions.

Herein, we demonstrate a unique supercapacitor composite electrode material that is originated from a sustainable cellulosic precursor via simultaneous one-step carbonization/reduction of cellulose/graphene oxide mats at 800 °C. The resulting freestanding material consists of mechanically stable carbon nanofibrous (CNF, fiber diameter 50–500 nm) scaffolds tightly intertwined with highly conductive reduced graphene oxide (rGO) sheets with a thickness of 1–3 nm. The material is mesoporous and has electrical conductivity of 49 S cm−1, attributed to the well-interconnected graphene layers. The electrochemical evaluation of the CNF/graphene composite electrodes in a supercapacitor device shows very promising volumetric values of capacitance, energy and power density (up to 46 F cm−3, 1.46 W h L−1 and 1.09 kW L−1, respectively). Moreover, the composite electrodes retain an impressive 97% of the initial capacitance over 4000 cycles. With these superior properties, the produced composite electrodes should be the “looked-for” components in compact supercapacitors used for increasingly popular portable electronics and hybrid vehicles.

Cellulose acetate and polyisocyanate copolymer synthesized by simultaneous mixing of cellulose acetate and polyisocyanate with acetone solution of Copper chloride and fumed silicon dioxide was carbonized in a silicon dioxide template. The composite structure and composition was studied with SEM, EDS and XRD. It was shown that the porous carbonaceous nanomaterial was synthesized where formed carbon was represented by coating on silicon dioxide and consisted of graphite, graphene and amorphous nonstructured carbon. Crystals of metallic copper with the size up to few µm were formed from Copper chloride after reduction of Cu2+ with products of organic compounds pyrolisis.Key words: carbon-silica nanomaterials, polyisocyanate, cellulosr acetate, fumed silica, copper chloride, carbonization.

Cellulose acetate and polyisocyanate copolymer synthesized by mechanical mixing of cellulose acetate, polyisocyanate and fumed silicon dioxide in the presence of nickel chloride was carbonized in silicon dioxide template. Copolymer and silicon dioxide template were formed simultaneously. Composite structure and composition was studied with SEM and EDS. SEM showed that porous carbonaceous nanomaterial was synthesized. Formed carbon is represented by coating on silicon dioxide, layered ribbon-like and fibrous structures in template pores with size from several nm (thickness) to several microns (length). Metallic nickel crystals up to 200 nm in size were fabricated in composite pores from Nickel chloride by reduction of Ni2 with products of pyrolysis of organic compounds. Key words: carbon-silica nanomaterials, polyisocyanate, cellulosr acetate, fumed silica, nickel chloride, carbonization.

Background: CYP1A2 is a very important gene for a potential genotyping. The objective of this work was to study the population frequencies of the corresponding 163A/C single nucleotide polymorphism of the CYP1A2 gene in the sampling of the Ukrainian population. Methods: Total sampling of genetic material (buccal epithelium) was collected in 102 subjects (48 males, 54 females) not related to each other. Genotype test of the participants of the study for CYP1A2 polymorphism (rs762551) was performed using the polymerase chain reaction. In accordance with the findings of genotyping the allele frequencies (р and q) were calculated. Results: The following distribution of genotypes in a sampling of the Ukrainian population under the 163A/C polymorphism of the CYP1A2 gene: AA - 36%, AC - 49% and CC - 15% in the subjects was revealed. The population allele frequencies of the 163A/C polymorphism of the CYP1A2 gene totaled pА = 0.6 and qС = 0.4. The population structure of the individuals does not deviate from the Hardy-Weinberg equilibrium, as may be seen from the lack of difference between the theoretically expected and the observed frequencies of the three genotypes. Conclusion: The genetic polymorphism found in the Ukrainian population is the basis for the recommendation of the genetic testing of 163A/C polymorphism of the CYP1A2 gene in the prescribing drugs - substrates of this gene.

The CYP2B6 is one of the members of the cytochrome P450 superfamily. This enzyme metabolizes a number of currently prescribed drugs and different compounds. In light of clinical significance of the CYP2B6∗6 variant of the CYP2B6 gene, the aim of this study was to investigate the distribution of one of the gene polymorphisms, namely, the 516G/T in the Ukrainian population.

In the present work, we report a sonication-assisted exfoliation method of graphene preparation enhanced by the use of microwave heating and “green” exfoliant – sodium carboxymethyl cellulose (NaCMC). Introducing microwave heating during sonication of graphite dispersions in aqueous solutions of NaCMC results in the formation of graphene dispersions with concentration as high as 4.29 mg/ml. It is found that drying the dispersions results in the formation of graphene/NaCMC composites with graphene content up to 38.65 wt%. A study of the composite with High Resolution Transmission Electron Microscopy and Raman Spectroscopy reveals the formation of few-layer graphene approximately below five layers. The as-prepared graphene/NaCMC composite shows higher capacities than commercial graphite in Li-ion half cells reaching 397 mAh/g (graphene) . Also, when the composite is used with a nanosilicon (33 wt%) in a Li-ion half cell high initial reversible capacities of 1611 mAh/g (Si) with good cyclability and rate capability have been reached.

Background: A key approach in modern medicine is the use of tactics of choosing drugs and their doses based on the specific characteristics of the individual patient, as well as determination of treatment regimens based on the genetic traits of the organism. This approach is part of personalized medicine and is based on pharmacogenetic testing. To study the real possibilities of conducting pharmacogenetic tests the questioning of the population of Ukraine has been performed for the first time, and the economic aspect of carrying out DNA tests has been studied. Methods: Field investigations were used in this work. The students of pharmaceutical, medical and biological specialties of higher schools of Ukraine, the medical staff, as well as persons having no relevance to the field of medicine or pharmacy were questioned. In our study 3143 respondents took part. Results: It has been determined that one third of the males and females interviewed in different occupational groups are ready at the moment to pay for testing depending on the cost of treatment. It has been shown that more than half of the respondents (71.8% males and 78.6% females) consider it possible to conduct DNA tests in Ukraine although it requires a significant investment. Conclusion: The opportunities of conducting pharmacogenetic testing in Ukraine taking into account the economic aspect have been studied. The studies have shown that it is necessary to raise the awareness of the population of Ukraine about pharmacogenetics with the purpose of further introduction of pharmacogenetic testing into clinical practice.

Exfoliated graphite (EG) has been modified with pyrolytic carbon produced by 750°C carbonization of poly(vinylidene fluoride) (PVDF), tolylene diisocyanate (TDI), and polyisocyanate (PIC) applied to the EG surface from solutions. The pyrolytic carbon obtained had the form of particles ranging in size from 200 nm to 1 μm. The microstructural characteristics of the carbon-carbon materials depend on the chemical composition of the carbon precursor: S = 15.8 to 63 m2/g; nitrogen sorption from 24.7 to 59.2 cm3/g (−190°C); micropore volume, up to 7.4 mm3/g; benzene vapor absorption from 0.07 to 0.27 g/g (20°C).

Nitrogen-doped carbon nanofibrous mats with the fiber diameters between 70 and 400 nm were synthesized from regenerated cellulose impregnated with ammonium chloride. Acting as a flame retardant, ammonium chloride provided the thermal stabilization of incompletely regenerated cellulose fibers, thus allowing their successful carbonization. Besides that, it improved the carbon yield from 13% to 20%. The method of carbon nanofibers (CNF) synthesis reported here is technologically simple and environmentally friendly since it significantly shortens the regeneration step and does not require water consumption for washing of the precursor fibers from deacetylation agents. More than that, introduction of nitrogen via NH4Cl impregnation led to an increase in the electrical conductivity of the obtained CNF samples, a fact which can make them useful for advanced electrochemical applications.

In the present work, we report for the first time one-pot synthesis of carbon nanotubes (CNTs) by pyrolysis of cellulose acetate (CA) cross-linked with polyisocyanate in the fumed silica template. NiCl2 was chosen as precatalyst for CNT growth. The diameter of CNTs is 24-38 nm and their wall thickness is 9-11 nm. The main role in the formation of CNTs by the pyrolysis of CA may be attributed to combination of closed macropores in the template formed by evolved CO2 during cross-linking reaction and mesopores formed by silica particles. The macropores acted as microreactors while the mesopores templated catalytic nanoparticles. The importance of this method for CNT synthesis reported here consists of the utilization of readily available renewable resource-CA. Moreover the method does not require preliminary synthesis of catalyst, it is technologically simple (can be performed in the conventional tube furnace), and hence it is energetically efficient.

Objective: Article describes the species composition of malaria mosquitoes dominating in the Kharkov region, Ukraine, season of their possible effective infection, as well as antimalarial precautions taken. Methods: When collecting the material, the conventional methods of evaluation of abundance of mosquitoes were used. Collection of larvae and pupae was carried out with standard butterfly net or photo tray with subsequent recalculation per m 2 . Results: On the territory of the region were studied 30 species of bloodsucking mosquitoes of such three genera as Anopheles, Culex, Aedes were found. Conclusion: Facts demonstrate the favorable environmental conditions for malaria spread such as; increase in the number of vectors, increase in precipitation, long temperature period of transmission of infection.

Increasing the energy density of Li-ion batteries is very crucial for the success of electric vehicles, grid-scale energy storage, and next-generation consumer electronics. One popular approach is to incrementally increase the capacity of the graphite anode by integratingsilicon into composites with capacities between 500 and 1000 mAh/g as a transient and practical alternative to the more-challenging,silicon-only anodes. In this work, we have calculated the percentage of improvement in the capacity of silicon:graphite compositesand their impact on energy density of Li-ion full cell. We have used the Design of Experiment method to optimize composites usingdata from half cells, and it is found that 16% improvements in practical energy density of Li-ion full cells can be achieved using 15to 25 wt% of silicon. However, full-cell assembly and testing of these composites using LiNi0.5Mn0.5Co0.5O2cathode have provento be challenging and composites with no more than 10 wt% silicon were tested giving 63% capacity retention of 95 mAh/g at only50 cycles. The work demonstrates that introducing even the smallest amount of silicon into graphite anodes is still a challenge andto overcome that improvements to the different components of the Li-ion battery are required.

This paper reports the strain sensitivity of flexible, electrically conductive, and nanostructured cellulose which was prepared by modification of bacterial cellulose with double-walled carbon nanotubes (DWCNTs) and multiwalled carbon nanotubes (MWCNTs). The electrical conductivity depends on the modifying agent and its dispersion process. The conductivity of the samples obtained from bacterial cellulose (BNC) pellicles modified with DWCNT was in the range from 0.034 S·cm−1to 0.39 S·cm−1, and for BNC pellicles modified with MWCNTs it was from 0.12 S·cm−1to 1.6 S·cm−1. The strain-induced electromechanical response, resistance versus strain, was monitored during the application of tensile force in order to study the sensitivity of the modified nanocellulose. A maximum gauge factor of 252 was found from the highest conductive sample treated by MWCNT. It has been observed that the sensitivity of the sample depends on the conductivity of the modified cellulose.

Carbon nanofibrous sheets (conductivity 1.9 to 35.5 S×cm-1, water contact angle up to 137°) consisting of amorphous fibers with diameter of 20 – 150 nm (C:O atomic ratio 25.4 – 86.0) were synthesized by carbonization of cellulose regenerated from electrospun cellulose acetate mats with three methods of alkaline deacetylation. It was established that C:O atomic ratio, conductivity and hydrophobicity depended on the regeneration method and on the temperature of carbonization. The highest flexibility, lowest conductivity and lowest water contact angle was observed for carbon synthesized from cellulose regenerated with NaOH in ethanol (0.05 mol/l) for 24 hours at room temperature. The highest conductivity, highest water contact angle and lowest flexibility was observed for carbon synthesized from cellulose regenerated with water solution of NaOH/NaCl (3.75 M NaOH, 2.1 M NaCl) during 15 minutes at 65°C.

Introduction: Facial and body asymmetry to some extent is present in all individuals. Because fluctuating asymmetry is of a stochastic nature, it cannot be studied at the level of individuals, but only its groups can be considering during studying the populations. Material and Methods: We conducted a survey of 200 students of 8–11 grades, from 13 to 17 years old, residents of Ukraine. Asymmetry measurements were made in the program GIMP-2.8. Results: Population distribution of eight points of the face asymmetry among the population of Ukraine was studied. Sex dimorphism was found under all average indicators of absolute and relative asymmetry. Higher indicators of asymmetry were common to males and also typical for the lower part of the face. Discussion and Conclusion: Obtained data complement the existing study on facial asymmetry in human. Some of our results are consistent with the existing data from previous studies of the world population, while others point to the differences of Slavic population in a number of features related to the facial asymmetry.

Nanostructured cellulose was modified by different concentration and volume of dispersed multi-walled carbon nanotube (MWCNT) and double-walled carbon nanotube (DWCNT) solutions and its electrical properties were studied. The resulting flexible cellulose films have an electrical conductivity sensitive to changes in CNT concentration and immersion time in solution. The conductivity increases with increasing immersion time and volume and concentration of dispersed solutions; the conductivity for bacterial cellulose (BC) pellicles modified with DWCNT was increased from 0.034 S cm-1 to 0.15 S cm-1 and for BC pellicles modified with MWCNT it was increased from 0.12 S cm-1 to 1.6 S cm-1 when the immersion time was increased from 24 h to 72 h. These results are significantly higher than in previously reported work [1]. The effect of strain on the resistance during application of tensile force is shown for a simple strain gauge employing cellulose with incorporated DWCNTs. The electrical resistance of the films displays a high sensitivity to strain. It seems that this sensitivity depends on the modifying conditions, where BC pellicles which are modified in a dispersed solution with a higher concentration of CNTs show larger changes in resistance with the changes in fractional extension

We will describe a methodology to prepare nano-Si / natural graphite composite using an established transformation manufacturing process without significant changes to the initial process flow, thus minimizing the cost of implementation. First, a baseline was established by investigating half-cells made with anode using a mixture of coated spherical natural graphite, nano-Si and LiPAA binder. Then, a composite of graphite / nano-Si was prepared by carbonizing a dry mixture of spherical graphite, nano-Si and petroleum pitch. The silicon content was below 20 wt.% toward graphite and the pitch-to-nano-Si was optimized. Following these guidelines, a series of Si/graphite composites were prepared by first performing a spheronization process to a dry mixture of natural graphite flakes, nano-Si and carbon precursors to disperse the silicon in the core and on the surface of the graphite matrix. Followed by a carbonization step to form the amorphous carbon coating simultaneously on the graphite and nano-Si surface. The morphology and chemical composition of the composites' surface was investigated using XPS, SEM and HRTEM and the possible formation of silicon oxides or carbides was evaluated by XRD. Tap density, surface area and PSD were performed to assess if the prepared powders reached the battery grade specifications. The composites show very high reversible capacity when evaluated in coin-type, Li-ion half cells.

Using poly(vinylidene fluoride) (PVDF) carbonization at 750° C in fine-particle silica and its mixtures with graphite, we have prepared carbon-loaded porous composites which offer benzene absorption from 0.90 to 1.52 ml/g, compressive strength of 6 MPa, and Brinell hardness of up to 18 MPa. We observed the formation of various nanostructures (spheres, spherical segments, and layered platelets) and sizes (several to hundred nanometers). X-ray photoelectron and energy dispersive x-ray spectroscopy data indicate the presence of C-C, C =C, CO, COO, and CHF groups on the carbon surface. X-ray emission spectroscopy data show that the silica matrix composite prepared via PVDF carbonization contains small carbon clusters weakly bonded to the matrix. The silica/graphite matrix composite contains multilayer carbon films strongly bonded to the matrix. The OK α spectra of both composites are similar to the spectrum of pure SiO2.

Carbons with valuable electrochemical characteristics are among the most convenient electrode materials used for energy storage. At the moment, their production is mostly reliant on unsustainable fossil fuels. A preferential sustainable production of enhanced carbonaceous electrodes can be achieved with more extensive utilization of abundant renewable resources instead of fossils. In this study, nitrogen-doped carbon nanofibers (CNFs) were synthesized from cellulose, the most abundant renewable resource, via consecutive steps of cellulose acetate electrospinning, subsequent deacetylation to cellulose, impregnation with nitrogen-containing additive (ammonium chloride), and carbonization. Results of material characterization showed that the carbonization of functionalized cellulose samples led to formation of CNFs doped with 4–5.6 at.% of nitrogen. In comparison with pristine CNFs N-doped samples had a slightly lower specific surface area, but higher conductivity and hydrophilicity. Moreover, electrochemical measurements indicated that the enhanced N-doped materials had about 2.5 times higher specific capacitance which was increasing throughout 1000 charge–discharge cycles. These results suggest that nitrogen doping method used in this study has a positive pseudocapacitive effect on the electrochemical performance of carbonized cellulose materials.

Supercapacitors are efficient energy storage devices with long lifetime and safe service. Their effectiveness, to a big extent, is dependent on electrode materials used for accumulation of energy in form of electrostatic charges. Over the last decades, variety of carbonaceous electrode materials has been used in supercapacitors. Mostly the production of such electrodes is still oriented on unsustainable fossil fuels as precursors instead of sustainable renewable resources. In this study, freestanding carbonaceous electrode materials for supercapacitors were derived from cellulose, the most abundant renewable resource. They were synthesized via carbonization of fibrillar cellulose impregnated with CNTs (carbon nanotubes). The ensuing composite materials consisted of a CNF (carbon nanofiber) scaffold (fiber diameter in the range of 50-250 nm) covered with layers of CNTs (tube diameter in the range of 1-20 nm). Moreover, these composites were tested as electrode materials for supercapacitors. Incorporation of the CNTs into the CNFs improved electrical conductivity and also increased the surface area of the produced composite materials, which led to high specific capacitance values (up to 241 F/g), cyclic stability, and power density of these materials in electrochemical measurements. These results suggest that cellulose-derived original CNF/CNT composites are sustainable and efficient carbonaceous electrodes for supercapacitors.

Aims To produce light-activated antimicrobial materials composed of the photodynamic dye phloxine B incorporated into paper or cellulose membranes and to investigate ability of these materials to decrease bacterial loads on their surfaces as well as on food surfaces that were in contact with these materials under illumination with regular white light. Methods and Results Antimicrobial cellulose-based materials with incorporated phloxine B were produced using a layer-by-layer deposition method. Antimicrobial properties of the materials were tested in model systems as well as for decontamination of food and food contact surfaces. Pseudomonas aeruginosa, Listeria monocytogenes and Bacillus anthracis were efficiently killed by exposure of the bacterial suspension to the dye-containing material under illumination with white light, but Salmonella Typhimurium and Escherichia coli O157:H7 were only partially affected. Application of the materials for decontamination of food surfaces artificially contaminated with L. monocytogenes was shown to be ineffective, while the self-decontamination of the material surface by exposure to white light resulted in eradication of L. monocytogenes cells from the material surface. Conclusions The developed materials showed significant self-decontaminating ability when under illumination; however, decontamination of food surfaces in contact with the developed materials was not achieved. Significance and Impact of the Study The study demonstrates the antibacterial activity of materials with incorporated photodynamic dyes when under illumination with regular-intensity white light. Possible uses of the light-activated antimicrobial materials for food processing, as food contact surfaces, and surfaces in public areas to prevent cross-contamination are discussed.

Increasing the energy density for Li ion batteries is very crucial for the success of EVs, grid-scale energy storage and next generation of power electronics. A holistic approach is required where the performance of the electrodes and electrolyte needs to be improved simultaneously. On the anode side, Si has been considered as the best candidate to give much higher capacities reaching, in theory, 10 times those of graphite. [1,2] However, in practice Si alone cannot deliver this high capacity reversibly due to many problems associated with volume expansion/shrinking during lithiation/de-lithiation. Also, current cathode materials have limited specific capacity to 150-200 mAh/g and can only be coated up to certain thickness before fracture or polarization takes place. A composite of silicon and graphite with capacities between 500 and 1000 mAh/g has been considered as a transient and practical alternative. In this work we have conducted theoretical and experimental study of silicon, graphite, and binder composite electrodes. We have calculated the percentage of improvement in capacity of composites and in energy density of full cells. We have tested more than 50 compositions in half cells with different ratios, binder type and silicon (shape, size and surface chemistry). Also, we have tested full cells using NMC cathode, a carbonate solvent mixture and various additives. We will show the result of our theoretical and experimental findings and demonstrate the actual parameters that need to be optimized in order to reach real improvements in practical energy density of Li-ion full cells. [1] Chae-Ho Yim, Fabrice M Courtel, Yaser Abu-Lebdeh,Journal of Materials Chemistry, 1(28), 2013 8234. [2] Nuha Salem, Matt Lavrisa and Yaser Abu-Lebdeh, 2015, Energy Technology, DOI 10.1002/ente.201500250.

Graphene and its composites have great potential as anode materials for Li-ion batteries (LIB) since their capacity was reported to exceed that of graphite, currently used as anode in most LIB [1].There are many methods to synthesize graphene, but there are still challenges to produce graphene at a large scale with desired properties that suit its perspective applications. Since there is yet no universal method for graphene production, especially that gives high yield, it would be reasonable to develop methods adjusted to specific applications e.g. electrochemical energy storage. Liquid ultrasonic exfoliation of graphene is very popular technique however satisfactory yield of exfoliation is usually achieved with either toxic organic solvents or in the water solutions of surfactants, the latter results in contaminated final product, which is unacceptable for electrochemical applications. In our work we used sodium carboxymethyl cellulose (NaCMC) as a water soluble “green” exfoliating agent for the high-yield graphene preparation. Since NaCMC is known to be a good binder for active electrode masses there is no need to remove it from as prepared graphene. Such approach allowed us simultaneous synthesis of graphene and preparation of electrode material for LIB. Microwave assisted method for the liquid phase graphite exfoliation was developed in the present work. Addition of microwave heating step to sonication of graphite dispersions in solutions of sodium carboxymethyl cellulose (NaCMC) resulted in formation of concentrated graphene dispersions of up to 4.3 mg/ml after 10 hours of sonication; concentration of graphene was increased for 34% compared to using sonication alone. HRTEM and Raman spectroscopy revealed formation of few-layer graphene (3-4 layers). It was found as well that graphene yield depends on the molecular weight of the NaCMC – the higher molecular weight the higher graphene yield (up to 59% increase of graphene yield was observed for NaCMC with 250000 molecular weight compared to NaCMC with 90000 molecular weight). Drying of prepared dispersions resulted in the graphene/NaCMC composites with graphene content up to 38.65%. Yield and concentration of graphene can further be improved by increasing sonication time and recycling of sediment. Graphene/NaCMC composite was tested as electrochemically active binder for using with Si nanoparticles in LIB electrodes. Si showed up to 51% capacity increase in the presence of graphene/NaCMC binder comparing to conventional NaCMC binder. N. Lavoie et al. in Y. Abu-Lebdeh and I. Davidson (eds) Nanotechnology for Lithium-ion batteries,117 (Springer, NY, 2013). A. Cieselski, P. Samori, Chem. Soc. Rev. 43, 381 (2014).

CoCl(2) containing honeycomb patterned films were prepared from cellulose acetate (CA)/CoCl(2)/acetone solutions by the breath figure method in a wide range of humidities. Size and pore regularity depend on the CA/CoCl(2) molar ratio and humidity. When replacing CoCl(2) with Co(NO(3))(2) or CoBr(2), no formation of ordered porosity in the cellulose acetate films is observed. According to data from scanning electron microscopy (SEM), Energy Dispersive X-ray Microanalysis (EDX), X-ray Diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy, the key role in the formation of honeycomb structures can be attributed to the physical and chemical properties of CoCl(2) - hygroscopicity, low interaction with CA, and extraction from CA/CoCl(2)/acetone solution by water droplets condensed on the surface of the CA/CoCl(2) solution. Obtained films are prospective for using in catalysis, hydrogen fuel cells, and optical sensing materials.

Results of studies of the electronic structure of carbon-containing porous materials derived by tolylene-diisocyanate (TDI) carbonization in a matrix of Al2O3 are presented in this paper. It has been established that products of TDI carbonization are fine spherical clusters (with their sizes of about 10 nm) that reveal a strong bonding with the matrix. The shapes of X-ray emission CKα and OKα bands are different for volume and surface parts of the materials. Our study reveals different electronic structures of the materials in volume and surface parts. It has been established that the shape of the X-ray emission CKα band of the volume part of products of carbonization of TDI in the Al2O3 matrix corresponds to that of mixture of the bands of fullerene C60 and graphite, but the shape of the band of the surface part resembles that of the CKα band of graphite. The shape of the X-ray emission OKα band of the volume part of the products of TDI carbonization resembles that of the band of γ-Al2O3, while that of the surface part corresponds to the shape of the OKα band of Al(OH)3.