Search

The salt of formula [H2EDTA2+][HSO4−]2 (dihydrogen ethylenediaminetetraacetate di(hydrogen sulfate(VI)) was used to examine the physicochemical properties of the resulting Ni layer and evaluate the applicability of the salt as a new additive for Watts-type baths. The Ni coatings deposited from baths containing [H2EDTA2+][HSO4−]2 were compared with those obtained from other baths. The nucleation of nickel on the electrode was proven to occur the slowest in the bath that contained the mixture of [H2EDTA2+][HSO4−]2 and saccharin compared with other baths. The addition of [H2EDTA2+][HSO4−]2 alone (bath III) generated a coating with a morphology similar to that obtained from bath I (without additives). Despite the similar morphology and wettability of the Ni-coated surfaces plated from various baths (all Ni coatings were hydrophilic with contact angles in the range of 68 to 77°), some differences in electrochemical properties were noted. The corrosion resistance for the coatings plated from baths II and IV containing saccharin (Icorr = 1.1 and 1.5 µA/cm2, respectively) and the mixture of saccharin and [H2EDTA2+][HSO4−]2 (Icorr = 0.88 µA/cm2), respectively, was similar or even better than the coating obtained from baths without [H2EDTA2+][HSO4−]2 (Icorr = 9.02 µA/cm2).

The aim of this paper is to present novel highly sensitive and stretchable strain sensors using data analysis to report on human live parameters using the Arduino embedded system as a proof of concept in developing new and innovative solutions for health care. The article introduces the solution of textile sensor origination with electrical resistance measurement using the mobile Arduino microcontroller in the designed/elaborated textile printed sensor. The textile sensor was developed by the screen printing technique based on the water dispersion of carbon nanotubes during printing composition. By stretching and squeezing the T-shirt during breathing, the electrical resistances of the printed sensor were changed. The measured resistance corresponded to the number of breaths of the person wearing the T-shirt. The microcontroller calculated the number of breaths as a number of electrical resistance peaks, which then led to monitoring human live parameters.

“According to Lingaro’s analysis, the return of a product generates 5 times more CO2 than the purchase itself. Thus, the optimization of online e-commerce purchasing processes is a serious challenge not only for business, but mainly for the protection of the environment and our global health.” Presentation of textiles and clothing in e-commerce in Poland has remained unchanged since the beginning of e-commerce (the setup of Allegro auction site in the early 2000s) until now with little exceptions of new technology trends powered by EU funds. In Poland, WearFits introduces an R&D solution in the form of a virtual fitting room presented in augmented reality (AR) view to decrease returns of textile clothing bought online. It uses an avatar of human size and shape of the customer’s body for fitting the three-dimensional models in AR view. The purpose of the article is to review the state of the art of presentation of clothing textiles in e-commerce in the world and in Poland for selling textiles online and to emphasize the problem of size matching in the context of returns.

This paper describes the use of a combination of two specific layers to protect the surface of low–carbon steel against electrochemical corrosion phenomena, which has not been published in the scientific literature so far. The layers include a black oxide film and siloxane coating, which are formed in the steel blackening and sol–gel processes, respectively. The so–obtained samples were subjected to surface morphology and physicochemical analysis (atomic force microscopy and Fourier-transform infrared spectroscopy) as well as electrochemical measurements, including AC and DC techniques. The physicochemical and surface morphology analysis allowed to prove the presence and adhesion of the siloxane coating to the surface of the black oxide layer, while the results of the electrochemical tests show that low–carbon steel modified this way is characterized by remarkable anti–corrosive properties, comparable to those of stainless steel.

The article presents the results of an attempt to use high-resolution X-ray micro-computed tomography (micro-CT) to model the thermal insulation of clothing as one of the most important parameters affecting the heat balance between a human and his/her surroundings. Cotton knitted fabric applied in functional clothing for newborns and aramid woven fabric used in multilayer protective clothing for firefighters were the tested materials. The 3D models of real textiles based on micro-CT images were developed. Next, the models were applied to heat transfer simulations using the finite volume method. The usefulness of the models was experimentally verified using thermography with real textiles. The simulation results were consistent with the measurement results and confirmed the relationship between the thermal insulation and geometry of the textiles on the one hand and the physical parameters of the raw materials from which they were made on the other hand.

The research and development of new carbon materials of electrochemical capacitors cause a huge interest in chemical power sources causes. The appropriate modification of carbon materials leads to an increase in supercapacitor capacitance. Therefore, activated carbon was modified by ozone treatment. The process of ozonation was carried out for 15, 30, 60, 120 and 240 min. Moreover, activated carbon was also modified by cobalt(II) hydroxide impregnation in order to construct asymmetric electrochemical capacitor. The performance of electrochemical capacitors has been examined by cyclic voltammetry and galvanostatic charge/discharge in 1 M H2SO4, 1 M Na2SO4 and 6 M KOH

The capacitance of electrochemical capacitors may be improved by providing additional charge originating from faradaic reactions. Faradaic reactions may originate from appropriate modification of the electrode or the electrolyte. The introduction of thiourea to the electrolyte is a novel approach. The tests in 1 mol dm−3 of Na2SO4 aqueous electrolyte (pH = 6.2) with thiourea addition showed a reversible redox process resulting in the increase of capacitance from 131 F g−1 for non-modified electrolyte to 229 F g−1 for those modified with thiourea. Keywords: Supercapacitor, Thiourea, Carbon electrodes, Faradaic reaction

The earlier obtained organosilicon derivatives of rapeseed oil were used for the production of coatings protecting steel surface against corrosion. Vegetable oils have been hitherto used for temporary protection of metals against corrosion, while thanks to the synthesis of appropriate organosilicon derivatives, it is now possible to create durable protective coatings. Due to the presence of alkoxysilyl groups and the use of the sol-gel process, the coatings obtained were bonded to the steel surface. The effectiveness of the coatings was checked by electrochemical methods and steel surface analysis.

This study discusses the effect of 3-(1,1,2,2,3,3,4,4-octafluoropentyloxy)propyltriethoxysilane (OFTES) based coatings on the anti-corrosive properties of 304 type stainless steel, which has not been described to date. The coatings were deposited from methanol using the anhydrous deposition method and influence of the sonication on this process has also been investigated. Anti-corrosive properties of modified and unmodified steel surfaces have been characterized by electrochemical and surface analysis methods. Since silicon is an element capable of forming bonds with both organic and inorganic substrates, these features allow to combine organofunctional silanes with metal as well as steel surfaces through metal O Si covalent bonds. A fluorinated alkyl chain, which is attached to the silicon atom, forms an effective barrier against an aggressive aqueous environment.

This paper discusses the effect of current collector (stainless steel 316L) corrosion on the performance of electrochemical capacitors operated in aqueous electrolytes. This topic seems to be often neglected in scientific research. The studied electrolytes were 1 M H 2 SO 4 , 1 M KI, 1 M Na 2 SO 4 , 1 M KOH and 6 M KOH. The corrosion process was investigated by means of selected direct and alternating current techniques. The surface of the current collectors as well as the corrosion products were characterised using scanning electron microscopy, energy-dispersive X-ray spectroscopy, Raman spectroscopy and atomic force microscopy. Stainless steel 316L in alkaline solutions is characterised by the lowest values of corrosion potentials whereas the potentials in acidic media become the most noble. Our studies show that corrosion potentials increase with decreasing pH value. This phenomenon can be explained with the formation of passive oxide films on the stainless steel current collectors. The passive oxide films are usually thicker and more porous in alkaline solutions than that in the other electrolytes. The processes occurring at the electrode/electrolyte interfaces strongly influence the working parameters of electrochemical capacitors such as voltage, working potentials of single electrodes, self-discharge as well as the internal resistance and cycling stability.

Aluminium anodisation processes were carried out in two different solutions i.e. in oxalic and sulphuric acid. Part of the samples was subjected to hydrothermal sealing in order to seal the pores on the oxide surface. Silane coatings were deposited from two solutions containing triethoxyoctylsilane and tetraethoxysilane. Surface analysis and spectroscopic methods were applied to characterize the pristine and coated samples. Anti-corrosive properties of all samples were assessed using electrochemical methods. It can be concluded that due to the condensation reaction between the anodised aluminium and silane compounds Al-O-Si covalent bonds are created. Fitted equivalent circuit parameters are distinctively different for the investigated systems. Additionally, the size of the particles in colloidal silane solutions was determined. Due to their size the colloidal particles cannot enter into the pores of the oxide layer but form a silane film on top. Thus they create a composite coating containing trapped air in the pores.

Electrochemical capacitors store the energy by the formation of the electrical double-layer at the electrode/electrolyte interface. These devices are characterized by high power density, short charge/discharge time and excellent cycling stability. The main goal of supercapacitor development nowadays is to increase their energy density and mentioned cycling stability. The former parameter could be improved by increasing the capacitance or operating voltage of the system, while the second by preserving current collectors from electrochemical corrosion phenomena. The increase of capacitance could be realized by the so-called pseudocapacitance effect, which can originate from the quick faradaic reactions at the electrode/electrolyte interface. These reactions can be induced by the appropriate modification of electrode in order to enforce the pseudocapacitive effect [1-4]. Electrochemical capacitors are composed of two electrodes separated by a separator and soaked in the electrolyte solution. Electrode material (mainly activated carbon) is coated on the surface of the current collectors made either of metals or stainless steel. In such a case, current collectors are exposed to corrosive electrolytes and can be subjected to corrosion processes [5-7]. There are several methods that are utilized to protect metals and steel from the harmful effects of electrochemical corrosion. One of them is the utilization of ionic liquids (ILs), which are added to an aggressive aqueous environment [8]. They act as corrosion inhibitors. This form of protection is being discussed in the scientific literature from about 20 years. A majority of articles describes the ability of this class of compounds to provide anti-corrosive protection for metal and steel. For these materials, an inhibitive influence on corrosion processes has been documented for dozens of ILs, vastly diversified in their chemical structure. A list of almost 90 investigated substances can be found in the literature [8]. Ionic liquids (ILs) are organic compounds which exhibit ionic structure and melting points below 100 degrees of Celsius. Due to their numerous advantageous properties, from some decades ILs stay in the scope of intense scientific interest, what results in the extensive research on possible ways to utilize them industrially. It covers various fields of IL application, for example as a solvent, an electrolyte, a catalyst, as a pharmaceutical or as corrosion inhibitors. In this work, the influence of ionic liquids additives on the performance of electrochemical capacitors is presented. Strictly, ionic liquids have been added to aqueous 1 M Na2SO4 electrolyte to inhibit corrosion processes on the surface of 316L stainless steel current collectors, which also influence the performance of electrochemical capacitors. Ionic liquids compounds were based on a common 2,5-dihydroxybenzenesulfonic anion. Electrochemical measurements were performed for a 2,5-dihydroxybenzenesulfonic acid, introduced to the electrolyte solution in 4 different concentrations ranging from 0,001% to 1%. Analogous tests were also conducted for 0,1% addition of 6 chosen ILs. All of ILs used in the research were composed of 2,5-dihydroxybenzenesulfonic anion and alkyldimethylammonium cation. The alkyl substituent of this cation varied, including n-ethyl, n-butyl, n-hexyl, cyclohexyl, n-octyl and n-decyl groups. The performed analysis proved an inhibitive effect of investigated compounds on the corrosion processes. The highest effectivities were observed for the ILs with bulkier alkyl substituent (i.e. containing cyclohexyl, n-octyl and n-decyl groups). On the basis of potentiodynamic polarization tests, a mixed corrosion inhibition mechanism was identified, with a predominant influence on the anodic process. Moreover, particular ionic liquids with the best anti-corrosive properties were used as additives to the electrolyte solution in electrochemical capacitors at a concentration of 0.1%. The results of electrochemical tests indicate a significant effect of the addition of ionic liquids on the working parameters of the electrochemical capacitors systems. This work was financially supported by the National Science Centre of Poland granted on the basis of the decision number 2018/31/B/ST8/01619 and by European Research Council (ERC) within ERC-StG-2017 project (grant agreement No. 759603) under the European Union’s Horizon 2020 research and innovation programme. References 1) F. Béguin, V. Presser, A. Balducci, E. Frackowiak, Adv. Mater., 26, 2219 (2014). 2) T. Brousse, D. Bélanger, J.W. Long, J. Electrochem. Soc., 162, A5185 (2015). 3) M. Graś, Ł. Kolanowski, J. Wojciechowski, G. Lota, Electrochem. Commun., 68, 28 (2018). 4) K. Fic, G. Lota, M. Meller, E. Frackowiak, Energy & Environmental Science, 5, 842 5 (2012). 5) J. Wojciechowski, Ł. Kolanowski, A. Bund, G. Lota, J. Power Sources 368, 18 (2017). 6) E. McCafferty, Introduction to Corrosion Science, Springer, New York (2010). 7) R.W. Revie, H.H. Uhlig, Corrosion and Corrosion Control, fourth ed., John Wiley & Sons, New Jersey (2008). 8) C. Verma, E.E. Ebenso, M.A. Quraishi, J. Mol. Liq., 233, 403 (2017).

Direct borohydride fuel cells (DBFCs) are devices which directly convert the chemical energy stored in the borohydride ion and oxidant into electrical energy as a result of redox reactions. Unfortunately, a significant amount of fuel is lost as a result of the undesirable hydrolysis reaction. The selection of an efficient borohydride hydrolysis inhibitor requires detailed knowledge regarding the interaction mechanism between the inhibitor molecule and electrode surface. In this study, various amounts of thiourea additives (0.011–1.600 mM) were tested to select the best fuel composition for DBFC application. When AB5-type anode was used, only partial inhibition of sodium borohydride hydrolysis was a desirable phenomenon. Partially released hydrogen results in the improvement of catalytic properties of the alloy. The addition of 0.016 mM thiourea does not inhibit the oxidation of borohydride, on the contrary, it increases the practical capacity from 27% to 41% of the theoretical value. Moreover, we indicate that the addition of thiourea prevents corrosion as well as degradation of the electrode surface. Pressure measurements confirmed the effectiveness of thiourea in relation to hydrogen evolution, while X-ray photoelectron spectroscopy and Raman spectroscopy revealed that the electrode surface was not poisoned.

A designed assembly of particles at liquid interfaces offers many advantages for development of materials, and can be performed by various means. Electric fields provide a flexible method for structuring particles on drops, utilizing electrohydrodynamic circulation flows, and dielectrophoretic and electrophoretic interactions. In addition to the properties of the applied electric field, the manipulation of particles often depends on the intrinsic properties of the particles to be assembled. Here, we present an easy approach for producing polystyrene microparticles with different electrical properties. These particles are used for investigations into electric field-guided particle assembly in the bulk and on surfaces of oil droplets. By sulfonating polystyrene particles, we produce a set of particles with a range of dielectric constants and electrical conductivities, related to the sulfonation reaction time. The paper presents diverse particle behavior driven by electric fields, including particle assembly at different droplet locations, particle chaining, and the formation of ribbon-like structures with anisotropic properties.

Chitin of poriferan origin is a unique and thermostable biological material. It also represents an example of a renewable materials source due to the high regeneration ability of Aplysina sponges under marine ranching conditions. Chitinous scaffolds isolated from the skeleton of the marine sponge Aplysina aerophoba were used as a template for the in vitro formation of $Fe_{2}O_{3}$ under conditions (pH [similar] 1.5, 90 °C) which are extreme for biological materials. Novel chitin–$Fe_{2}O_{3}$ three dimensional composites, which have been prepared for the first time using hydrothermal synthesis, were thoroughly characterized using numerous analytical methods including Raman spectroscopy, XPS, XRD, electron diffraction and HR-TEM. We demonstrate the growth of uniform $Fe_{2}O_{3}$ nanocrystals into the nanostructured chitin substrate and propose a possible mechanism of chitin–hematite interactions. Moreover, we show that composites made of sponge chitin–$Fe_{2}O_{3}$ hybrid materials with active carbon can be successfully used as electrode materials for electrochemical capacitors.

More and more people in the world contend with overweight or obesity, and this phenomenon at the moment is being recognized as one of the most important problems of modern civilization observed in many developed countries. Change of the lifestyle connected with turning from the active life to the more sedentary one and bad eating habits led to the development of overweight and obesity at an alarmingly fast rate with the parallel development of interests directed on conducting the research and looking for the effective methods of fighting against the overweight and obesity. The aim of the study was to evaluate some parameters of body weight among people being put on the healthy training on the rehabilitation and keep-fit tables Slender-Life.A group of 50 patients treated in sanatorium were included into the observation. Double measurement of body weight and thickness of the skin and fat were performed during the first and last days of the fifteen day training on the formerly mentioned tables.The statistically important decrease of examined parameters including the real body weight, fat mass, the BMI indication and the thickness of the skin and fat folds was detected.The healthy training on the rehabilitation and keep-fit tables Slender-Life causes the increase of the body fat-free weight. The positive acceptation of the rehabilitation on tables Slender-Life proves it should be applied.

The results of numerous studies have recently revealed that the motor activity are able to prolong the live of middle-aged and elderly human subjects preventing serious diseases and premature death. A regular physical activity decreases the number of fat cells and increases their vulnerability to insulin. Physical exercises regulate the metabolic disorders observed in obesity. The physical activity of persons with lipid disorders may induce some favorable changes and an increase the HDL of cholesterol fraction. The influence of physical activity on fat and carbohydrate changes was confirmed in some studies. The aim of the study was to evaluate the selected parameters of the fat and carbohydrate changes in subjects after 15 days health-related training performed on rehabilitation and reconditioning tables SLENDER-LIFE.A group of 50 patients during health-resort therapy were examined on the first and last day of training for biochemical blood parameters.The examined biochemical parameters were reduced statistically significantly in all subjects, as follows: the total cholesterol concentration, the LDL value fraction of cholesterol, triglycerides, and the glucose concentration.It has been documented that the level of the HDL fraction of cholesterol and the basic energy index were increased in the examined subjects. The training on the rehabilitation and reconditioning tables has been confirmed by the subjects as useful and efficient.

This paper reports on the impact that the corrosion of the stainless steel current collectors has on the performance fade of a symmetric, carbon/carbon electrochemical capacitor, operating with an aqueous electrolyte (1 M Na2SO4). The results obtained by applying electrochemical ageing protocols (voltage– holding tests) confirm that the current collector of the positive electrode undergoes tremendous degrada-tion during 200 h in the charged state. To prevent the detrimental impact of the corrosion, a hydrophobic siloxane coating has been successfully applied. In the case of siloxane–protected current collectors that are subjected to identical ageing protocols, no significant deterioration in the electrochemical capaci-tor performance was observed. The siloxane coating reduces the electrochemical corrosion rate of 316 L stainless steel significantly, as the potentiodynamic polarization tests and the electrochemical impedance spectroscopy results show. The presence of the coating is demonstrated by the water contact angle mea-surements, atomic force microscopy and energy–dispersive X–ray spectroscopy analysis.