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We describe a metal hydride (MH) hydrogen storage tank for light fuel cell vehicle application developed at HySA Systems. A multi-component AB2-type hydrogen storage alloy was produced by vacuum induction melting (10 kg per a load) at our industrial-scale facility. The MH alloy has acceptable H sorption performance, including reversible H storage capacity up to ∼170 NL/kg (1.5 wt% H). The cassette-type MH tank was made up of 2 cylindrical aluminium canisters with transversal internal copper fins and external aluminium fins for improving the heat exchange between the heating medium and the MH tank. Heat supply and removal was provided from the outside using air at T = 15–25 °C. The MH tank was tested at the conditions of natural or forced (velocity ∼2 m/s) air convection. The tests included H2 charge of the tank at P = 15–40 bar and its discharge at P = 1 bar. The tank in the H2 discharge mode was also tested together with open cathode low-temperature proton exchange membrane fuel cell (LT PEMFC).

This work describes an attempt to improve the physical and electrochemical parameters of PEM fuel cells that have electrodes modified by titanium and silicon dioxides. A customized design of membrane electrode assemblies was proposed which is characterized to have an around 6 times higher concentration of catalyst at the cathode side (2.0 mgPt cm−2) in order to investigate the influence of anode catalyst support treatment. Anode catalyst support materials were modified using pristine TiO2 and TiO2–SiO2–VTMS – the composite was crosslinked with the aid of vinyltrimethoxysilane. Surface area and porosity analysis was carried out with the aid of BET, BJH, t-plot and Horvath–Kawazoe (H–K) theories for particular components of the support materials and their catalyst mixtures. The experiment revealed a positive influence of TiO2–SiO2–VTMS (BET 321.9 m2 g−1, BJH 3.7 nm) on the anode catalyst layer in terms of surface area (3-times increase, 75 m2 g−1) and average pore size (decrease from 25.3 to 15.7 nm). Additionally, favourable microporosity (pores less than 2 nm) was introduced to the material according to the H–K analysis results (10.3 m2 g−1, 0.65 nm). Electrochemical experiments, which include polarization curves, electrochemical impedance spectroscopy and cyclic voltammetry, have demonstrated the change of behaviour for the fabricated fuel cells with modified anodes against the reference sample. The mitigation of charge and mass transfer resistance (by 15–20%, 50 mV at 200 mA cm−2), the improvement of power density (up to 72%, 217 mW cm−2) and a better exposure of the catalyst to the reactants of an electrochemical reaction were observed for fuel cells modified by both pristine TiO2 and the hybrid TiO2–SiO2–VTMS-based compound.

The effect of the presence of titanium dioxide in two new imines, (E,E)-(butane-1,4-diyl)bis(oxybutane-4,1-diyl) bis(4-{[(benzo[d][1,3]thiazol-2-yl)methylidene]amino}benzoate) (SP1) and (E)-N-[(benzo[d][1,3]thiazol-2-yl)methylidene]-4-dodecylaniline (SP2), on the properties and stability of imine:TiO2 composites for organic device applications were examined. The investigated titanium dioxide (in anatase form, obtained via the sol–gel method) exhibited a surface area of 59.5 m2/g according to Brunauer–Emmett–Teller theory, and its structure is a combination of both meso- and microporous. The average pore diameter calculated by the Barrett–Joyner–Halenda method was 6.2 nm and the cumulative volume of pores was 0.117 m3/g. The imine SP1 exhibited columnar organization (Col), while SP2 revealed a hexagonal columnar crystalline phase (Colhk). The imine:TiO2 mixtures in various weight ratio (3:0, 3:1, 3:2, 3:3) showed a lower energy gap and HOMO–LUMO energy levels compared to pure TiO2. This implies that TiO2 provides not only a larger surface area for sensitizer adsorption and good electron collection, but also causes a shift of the imine energy levels resulting from intermolecular interaction. Also the temperature of the phase transition was slightly affected with the increase of TiO2 concentration in imine-based composites. The changes observed in the Fourier transform middle-infrared absorption (FT-MIR) spectra confirmed the significant influence of TiO2 on structural properties of both investigated imines. Similar interactions of oxygen vacancies existing on the TiO2 surface with SP1 and SP2 were observed. The imine:TiO2 mixtures showed good air stability and reusability, which demonstrates its potential for organic device applications.

We investigate bilateral set-valued stochastic integral equations and these equations combine widening and narrrowing set-valued stochastic integral equations studied in literature. An existence and uniqueness theorem is established using approximate solutions. In addition stability of the solution with respect to small changes of the initial state and coefficients is established, also we provide a result on boundedness of the solution, and an estimate on a distance between the exact solution and the approximate solution is given. Finally some implications for deterministic set-valued integral equations are presented.

Purpose This paper aims to present and discuss the requirements for flying targets which sometimes are contradictory to each other and to perform a trade-off analysis before the design activity is started. It also aims to demonstrate conceptual and preliminary design processes using a practical example of PW-61 configuration and to show how results of experimental flight tests using a scaled flying target will be described and analyzed before manufacturing the full scale flying target. Design/methodology/approach An important part of the paper consists of the selection of tailplane configuration of the flying target UAV to protect some expensive on-board systems against serious damages and to obtain a sufficient dynamic stability, independently of the amount of the petrol in fuel tank. Inverted V-tail, U-tail and H-tail configurations were considered and compared both, theoretically and in-flight experiments. Findings Flight dynamics models and associated computational procedures were useful both in a preliminary design phase and during the final assessment of the configuration after flight tests. Selection of the tailplane configuration for the flying target UAV is very important to protect some expensive on-board systems against serious damages and to obtain a sufficient dynamic stability, independent of the amount of the petrol in fuel tank. Practical implications Flying targets should be speedy, maneuverable, cheap, easy in deployment and multi-recoverable (if not destroyed by live ammunition), must have relatively low take-off weight and an endurance of at least 1 h. This paper can be useful for proper selection of requirements and preliminary design parameters to make the design process more economically effective. Originality/value This paper presents very efficient methods of assessing the design parameters of flying targets, especially in an early stage of the design process. Stability computations are performed based on equations of motion and are supplemented by flight tests using the scaled flying models. It can be considered as an original, not typical, but very practical approach because it delivers lots of data in the early design stages at relatively low cost.

Graphene oxide (GO) was used as an additive to the anode, to modify the electrochemical properties of polymer fuel cells (PEMFC) based on Nafion. GO was obtained by modified Hummers method and fully characterized by Raman, FTIR, X-ray, TEM, electrochemically (CV) and Surface Area and Porosity Analyzer. PEMFC with a GO-based anode containing about 30% less Pt, was constructed and compared with a cell with standard anodes. The electrodes were electrochemically tested at 25 and 60 °C. A maximum power density of 134 mW/cm 2 with a current density of 374 mA/cm 2 was achieved for PEMFC with GO-based anode at 60 °C. The electrochemical surface area (ECSA) of the PEMFC with GO-based anode was about two times higher than that of the reference device. The electrochemical characterization as well as the Brunauer–Emmett–Teller (BET) and Barrett–Joyner–Halenda (BJH) analysis indicate that GO in the anode reduced Pt agglomeration, as a consequence of the increased surface area and decreased average pore width, compared with the reference electrode. Well-fitted equivalent circuits were proposed and discussed after an electrochemical impedance spectroscopy study of the constructed devices.

In this review paper we summarize recent research trends for polymer fuel cells (PEMFCs) that utilize various graphene materials described in articles published since 2007. We propose to analyze the influence of graphene in PEMFCs in three aspects: (i) as an electrode (anode or cathode), (ii) as an additive to polymer electrolyte and (iii) as a filler to bipolar plates along with some discussions on future research directions. In Section 2 of this review, we shortly present the fundamental processes of fuel cells along with important parameters such as hydrogen oxidation and oxygen reduction reactions, polarization losses, exchange current density, open circuit voltage and efficiency for fuel cells. Additionally, with curt description of various kinds of fuel cells and types of polymers applied in PEMFCs. Moreover, we discuss briefly different synthetic routes of graphene and describe selected graphene properties ( Section 3 ). In Section 4 , we analyze in detail the possibilities of applied graphene or its derivatives in various places in PEMFCs. Graphene applied to PEMFCs has a significant contribution on the increased electrical or ionic conductivity, better mechanical durability and corrosion resistance, and higher electrochemical surface area, depending on the fuel cell component that is modified. For instance, taking into consideration the function of graphene in polymer fuel cells and based on the current review, the highest value of maximum power density of 0.742 W cm −2 was found for PEMFC with graphene utilized as an anode support. The promising results open the way for the usage of graphene as a prospective material for application in fuel cells. However, the main difficulty of graphene application is the fact that this material has to be sufficiently separated by additional compounds to prevent restacking of graphene sheets.

We synthesized two new, air-stable and environmentally friendly polyazomethines and characterized their photovoltaic and electro-chemical impedance spectroscopic properties. Two polyazomethines with one (25Th-DMB) or three (2252Th-DMB) thiophene ringswere synthesized and tested as donors in the active layer in solar cells. The investigated polymer solar cells contained different amountsof PCBM and PC 71 BM. The bulk heterojunction polymer solar cells were fabricated and studied, considering the architecture of thedevices (i.e., LiF, TiO 2 , and TiO 2 :Ag) and the fabrication conditions (i.e., air, inert gas, and annealing). The highest power conversionefficiency, which was equal to 0.52% under simulated 100 mW/cm 2 AM 1.5G irradiation, was determined for the device using polyazome-thine with three thiophene rings and PC 71 BM created in air with the ITO/PEDOT:PSS (100 cP)/2252Th-DMB:PC 71 BM (1:2)/Al archi-tecture. In addition, the power conversion efficiency was strongly dependent on the viscosity of the PEDOT:PSS used. 2015 Elsevier Ltd. All rights reserved.

Binary and ternary membranes were prepared by immersion of Nafion-115 in 2,2′-bis(4-aminophenyl)-5,5′-bibenzimidazole (BAPBI) or/and in imidazole (Im) and were used in proton exchange membrane fuel cells (PEMFCs) with Pt/C gas diffusion electrodes and graphite single-serpentine monopolar plates. Membranes were activated in 0.2 M H2SO4. BAPBI was synthesized in poly(phosphoric) acid and the chemical structure was confirmed by 1H, 13C NMR and ATR-FTIR spectroscopy. Membranes were characterized by FTIR spectroscopy, TGA, AFM techniques. Also the water uptake was determined. PEMFCs were investigated by electrochemical impedance spectroscopy, polarization curves, cyclic voltammetry and linear sweep voltammetry taking into consideration the kind of imidazole applied and the temperature used (25 or 60 °C). The maximum power density of 146 mW/cm2 at the current density of 345 mA/cm2 was detected for Nafion-115-BAPBI membrane. For all constructed PEMFCs the efficiency at 0.6 V was found about 41%. The immersion of Nafion-115 in Im, BAPBI or BAPBI-Im increased the thermal stability and mechanical properties of membranes. The Nafion-115-BAPBI membrane showed good prospective for application in PEMFCs while in opposite to Nafion-115-Im, the poisoning effect on Pt catalyst was not observed.

Proton exchange membranes based on perfluorosulfonic acid (PFSA, Nafion-115) and fluorine-containing polybenzimidazole (PBICF3), and imidazole (Im) were prepared by immersion of Nafion-115 into PBICF3, Im and both of them. Fluorine-containing polybenzimidazole was synthesized from 3,3′-diaminobenzidine and 2,2-bis-(4-carboxyphenyl)hexafluoropropane. Obtained four membranes (PFSA–PBICF3–Im, PFSA–PBICF3, PFSA–Im and PFSA) were used to assemble single polymer fuel cells. All membranes were characterized by FT-IR spectroscopy, TGA (DTG) analyses and water content. For Nafion-115 membrane immersed in PBICF3–Im, the increase of water uptake in the range from 1.6 to ca. 3% in comparison to unmodified electrolyte was found. Constructed PEM single cells were investigated by electrochemical impedance spectroscopy, polarization curves and two voltammperometric methods (LSV and CV). Influences of PBICF3, Im and mixture of both of them in defined conditions, on the thermal and electrochemical properties of Nafion-115, were analyzed in details. The maximum power density of 124 mW/cm2 at the current density of 347 mA/cm2 was detected for PFSA–Im membrane. The immersion of Nafion-115 in PBICF3, Im and PBICF3–Im caused an increase of ionic conductivity from 2.16 mS/cm (for Nafion-115) to 3.48 mS/cm for PFSA-Im.

The effect of the presence of titanium dioxide in two new imines, (E,E)-(butane-1,4-diyl)bis(oxybutane-4,1-diyl) bis(4-{[(benzo[d][1,3]thiazol-2-yl)methylidene]amino}benzoate) (SP1) and (E)-N-[(benzo[d][1,3]thiazol-2-yl)methylidene]-4-dodecylaniline (SP2), on the properties and stability of imine:TiO2 composites for organic device applications were examined. The investigated titanium dioxide (in anatase form, obtained via the sol–gel method) exhibited a surface area of 59.5 m2/g according to Brunauer–Emmett–Teller theory, and its structure is a combination of both meso- and microporous. The average pore diameter calculated by the Barrett–Joyner–Halenda method was 6.2 nm and the cumulative volume of pores was 0.117 m3/g. The imine SP1 exhibited columnar organization (Col), while SP2 revealed a hexagonal columnar crystalline phase (Colhk). The imine:TiO2 mixtures in various weight ratio (3:0, 3:1, 3:2, 3:3) showed a lower energy gap and HOMO–LUMO energy levels compared to pure TiO2. This implies that TiO2 provides not only a larger surface area for sensitizer adsorption and good electron collection, but also causes a shift of the imine energy levels resulting from intermolecular interaction. Also the temperature of the phase transition was slightly affected with the increase of TiO2 concentration in imine-based composites. The changes observed in the Fourier transform middle-infrared absorption (FT-MIR) spectra confirmed the significant influence of TiO2 on structural properties of both investigated imines. Similar interactions of oxygen vacancies existing on the TiO2 surface with SP1 and SP2 were observed. The imine:TiO2 mixtures showed good air stability and reusability, which demonstrates its potential for organic device applications.

Streszczenie: Artyku³ stanowi II cz. ) pracy przegl¹dowej dotycz¹cej polimerowych ogniw paliwowych (fuel cells). Omowiono rodzaje polimerow wykorzystywanych w ogniwach paliwowych: polimery fluorowane, polimery sulfonowane i polimery aromatyczne oraz praktyczne zastosowania w skonstruowanych na ich podstawie ogniwach. Opisano zalety i wady omawianych polimerow w kontekœcie ich aplikacji w ogniwach paliwowych. Przedstawiono mo?liwoœci tworzenia mieszanek polimerowych na bazie polimerow [Nafion ® , poli(fluorek winylidenu) (PVDF), poli(2,6-dimetylo-1,4-tlenek fenylenu) (PPO)] i polibenzimidazoli (PBI) oraz domieszek zarowno organicznych (imidazol, dietyloamina, PBI), jak i nieorganicznych (ZrP, SiO 2 , TiO 2 , BPO 4 ,H 3 PO 4 ,S n 0,95 Al 0,05 P 2 O 7 -P x O y , CsHSO 4 ). Podano przyk³ady aplikacji ogniw paliwowych z podzia³em ze wzgledu na sposob ich wykorzystania: mobilny, stacjonarny i na potrzeby transportu. S³owa kluczowe: polimery, wodor, ogniwa paliwowe z elektrolitem polimerowym, zastosowania ogniw paliwowych. Polymer fuel cells. Part II. Types of polymers and applications

The paper is a literature review concerning polymer fuel cells. In the first part the structure, principle of operation and types of fuel cells (FC) are discussed. In-situ techniques used for evaluation of FC parameters in a single cell or assembled stacks, such as current-voltage characteristics (polarization curve), current interruption method, cyclic and linear sweep voltammetry, electrochemical impedance spectroscopy, cathode discharge and current mapping are presented. The mechanism of operation and functions of fuel cell components are discussed in details using the example of PEMFC (Polymer Electro- lyte Membrane or Proton Exchange Membrane fuel cells). Two types of PEMFC are distinguished, i.e. HT (High Temperature) and LT (Low Temperature) indicating the advantages of high-temperature opera

In this article, two polybenzimidazoles (PBIs) were synthesized by the polycondensation reaction of 3,3′-diaminobenzidine with terephthalic acid ( p-PBI) or isophthalic acid ( m-PBI) for application in high-temperature proton exchange membrane fuel cells. Two kinds of purification (P1, P2) were applied to clean the polymers. The chemical structure of PBI polymers was confirmed using Fourier transform infrared (FTIR) spectroscopy. Polymers after P1 can be soluble and cast into film only from hot sulfuric acid solution (H2SO4), whereas both polymers after P2 were soluble in dimethylacetamide solution. Polymer films cast from H2SO4 were investigated using FTIR. The thermal stabilities of PBIs and PBI films were studied using the thermogravimetric analysis and the first derivative of the TG method. The temperature of 5% weight loss ( T5%) for both PBIs ranges from 136 to 312°C under nitrogen atmosphere, depending on the dicarboxylic acid used and the kind of purification. The PBI films exhibited T5% at 55°C because of the protonation of nitrogen atom in PBI by hydrogen atom of hydroxyl group in H2SO4. Electrical behavior of the two polymers was tested using electrochemical impedance spectroscopy for gold (Au)/PBI/Au architecture. For both measured polymers, Nyquist plots are presented with fittings based on circuit models.

Various unfunctionalized heteroaromatic N-oxides are efficiently deoxygenated to the corresponding bases under mild conditions by treatment with the novel reagent TiCl4/SnCl2.

The reductive coupling of benzophenone to tetraphenylethene was studied. The coupling reagent, low-valent titanium, was obtained after reduction of TiCl4. The results are compared with those of similar couplings using low-valent titanium obtained after reduction of TiCl3. E.s.r. measurements and chemical observations show that the TiCl4-and the TiCl3-system behave completely analoguous with respect to reduction to low-valent titanium as well as with respect to reactivity towards ketones and alcohols.

Active metal slurries, prepared by the reduction of TiCl3, TiCl4, NbCl5, MoCl5 and WCl6 with LiAlH4 in THF, can bring about the reductive coupling of benzophenone to tetraphenylethene. Yields depend critically on the metal used.

The catalytic Ni-Ti system was studied in the Fischer-Tropsch reaction in a flow microreactor system under normal pressure. Nickel-titanium was used as a crystal system reduced in a flow of hydrogen. No support was used. The influence of the titanium on the yield of higher hydrocarbons was observed

The reaction of acetone with a low-valent titanium species anchored on silica gel was studied in heterogeneous media. Aldol type condensation products, mesitylene and mesityloxide, were observed as main products. The influence of nickel and cyclopentadienyl ligands on the reaction was observed.

Following the successful applications of a titanium (O) slurry in the deoxygenation of aromatic N-oxides, we attempted to achieve this method for the reduction of a nitro- group in pyridine derivatives. In general, only aminopyridine derivatives were formed in 85-98% yield. The advantage of this excellent reducing agent consists in mild reaction conditions and high yields of products, as well as in the selectivity of the reaction.

Proton exchange membrane fuel cells (PEMFCs) with Pt/C gas diffusion electrodes and graphite single-serpentine monop- olar plates were constructed based on an aromatic poly(etherimide) with isopropylidene groups (PI)/imidazole (Im) and a popular Nafion-115 matrix. The electrochemical properties of PEMFCs were tested at 25 and 608C. The maximum power density of 171 mW/ cm 2 and the maximum current density of 484 mA/cm 2 were detected for Nafion-115/PI membrane. For both constructed PEMFCs the efficiency at 0.6 V was found about 41%. Immersion of Nafion-115 in PI or PI/Im increased the thermal stability and mechanical properties of membranes. Thermal, mechanical properties and morphology of membranes were characterized by TGA, and AFM tech- niques including force spectroscopy. Interactions between the components in composite membranes were established by FT-IR. V C 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42436.

Titanium slurries, prepared by reduction of titanium chlorides with LiAlH4, are not only effective in couplings of ketones and aldehydes to alkenes, but also in reductive couplings and reductions of other functional groups.

Decomposition of formic acid has been studied at 250°-400°C on some heterogeneous catalysts. Alumina, silica, natural (clinoptilolite) and synthetic (3A, ZSM-5) zeolites were used as catalysts. H-ZSM-5 mixed with γ-alumina has been found to be the very good catalyst to prepare pure carbon monoxide in a laboratory practice.

The purpose of this article is the analysis of Peter Singer's concept of animal legal personality. Although it is an ethical idea, some doctrine representatives refer to it and prove that legal personality of animals is a necessity. Peter Singer's concept is based on the utilitarianism of preferences although it also refers to classical utilitarianism. His followers strongly criticize the current model of animal legal protection. It turns out, however, that the foundation of animal and human being protection is timeless and must be based on animals nature and a human being as a person. Whereas, the analysis of Peter Singer's concept leads to the conclusion that it is based on cognitive mistakes, concerning mostly human nature. In consequence, Peter Singer's concept of utilitarianism not only does not help better animal protection, but is also a threat to human rights protection.

The application of the TiCl 4 /SnCl 2 reagent system in the reductive deoximation of various ketoximes and aldoximes under mild conditions is reported. The corresponding carbonyl compounds were formed in high yields

A model is discussed for the titanium species, [M], used in reductive couplings (McMurry Synthesis). Evidence is given for the presence of aluminium(0) in [M], generated in the TiCl3/LiAlH4 system. Reactions of this [M] with alcohols showinter alia titanium(III) signals with superimposed Al-splittings in the e.s.r. spectra, thus proving the existence of mixed Ti-Al complexes in the TiCl3/LiAlH4/ROH system.

Heteroaromatic N-oxides bearing various functionalities are readily and selectively converted under mild conditions into the corresponding bases using TiCl4/SnCl2.

Various unfunctionalized heteroaromatic N-oxides are efficiently deoxygenated to the corresponding bases under mild conditions by treatment with the novel reagent TiCl4/SnCl2.

Titanium slurries, prepared by reduction of titanium chlorides with LiAlH4, are not only effective in couplings of ketones and aldehydes to alkenes, but also in reductive couplings and reductions of other functional groups.

Silicagele mit einem Na-Ionengehalt von 0-O,9 mMol/g wurden thermogravimetrisch untersucht und eine Beziehung zwischen der Menge adsorbierten Wassers und dem Na-Ionengehalt wird festgestellt.

The reduction of nitro compounds and the deoxygenation of N-oxides with low-valent titanium reagents were studied. The reaction conditions were optimized. Both the inorganic and the organic part of the reaction are discussed. The reaction mechanism is deduced from stoichiometric studies and EPR measurements. Formation of an intermediate complex of an organic anion-radical with titanium is proposed as the key step in the reduction of nitro compounds and the deoxygenation of N-oxides with low-valent titanium. In general, this mechanism is similar to that proposed earlier for the reductive coupling of ketones.

The application of the TiCl 4 /SnCl 2 reagent system in the reductive deoximation of various ketoximes and aldoximes under mild conditions is reported. The corresponding carbonyl compounds were formed in high yields