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This paper analyzes data on the concentration and dynamics of 137Cs and 90Sr in marine organisms on the Arctic shelf under modern conditions (2013–2018). It is shown that the radiation pollution of the Arctic sea biota is low and poses no danger to humans. The dynamics of radionuclide pollution of macrophyte and fish suggests that self-purification of the biotic component of the ecosystem occurred in several stages determined by a change in the generations in the hydrobiont populations. Fish are most sensitive to radiation pollution and the most studied component of marine biota. In the study of modern radioactive contamination of the Arctic seas, attention should be focused on local waters, where an increase in isotope concentrations could be possible owing to the episodic leakage of radioactive materials.

Currently, we are witnessing active development of urban building construction, which dictates new requirements for the infrastructure of water supply and sanitation. These requirements are aimed at improving the reliability and compliance with stringent environmental standards. Dispatch supervision and control of water supply networks are among the key tasks that have to be solved under such conditions. The problem of implementing such systems lies in difficulty of setting up power supply to the equipment used in these systems. The power supply of such systems is as a rule provided by using storage batteries, which entails the need for periodic maintenance of these systems and thereby increases the cost of their operation. The problem can be solved by using an autonomous source of electricity. The energy of the water flow in the pipeline is proposed to be used as such source. The possibility of setting up an autonomous dispatch control system for housing and utility services based on a hydrogenerator is estimated. The study is carried out by analyzing the hydraulic parameters of a bypass pipeline installed on a large-diameter pipeline. To determine the flow velocity and pressure in the bypass pipeline, the fluid flow is modeled in it. The modeling results and their subsequent analysis made it possible to calculate the range of power produced by the hydrogenerator and estimate the possibility of setting up an autonomous dispatch control system.

This research compared the impacts of Persian and English cultural background knowledge on Iranian EFL learners’ listening skill. To that purpose, the Oxford Quick Placement Test (OQPT) was given to 86 Iranian EFL students; 50 of them were chosen as research participants. The respondents were then divided into two equal experimental groups (EGs) at random (Persian culture and English culture). A listening pretest was then given to both groups. The individuals in both EGs were then given the treatment. The researchers taught one EG by using the English cultural materials, while they taught the other group through the Persian cultural materials. The data were analyzed by utilizing paired samples and independent samples t-tests after the listening posttest was administered. The results showed that both EGs performed better on their posttests than on their pretests, and that there were no significant differences between the impacts of English cultural background knowledge and Persian cultural background knowledge on the listening skills of EFL students. The implications of this research can persuade EFL English teachers to incorporate more cultural-based materials into their teaching process.

The paper deals with optimizing the desktop processing of the tanks’ terrestrial laser scanning data in assessing their stressstrain state (SSS). The basic concepts to optimize the desktop processing are established and analyzed, thus providing the means to reduce the spent resources and time of PC work without losses to the final result of the tanks’ SSS assessment.

The method of remote neutron and gamma spectrometry of bodies in the solar system (the Moon, Mars, and Mercury) has been used for several decades to estimate the nuclear composition of these objects and the hydrogen abundance in their subsurface layers. Proportional gas counters based on helium-3 (3He), which have the maximum efficiency of detecting thermal and epithermal neutrons, are used most often for measuring the low-energy neutron component. However, the data from LEND and FREND space experiments with large-volume and high-pressure helium counters revealed the noise contamination of lower channels of the neutron component due to the sensitivity of such counters to cosmic charged particles. The model of a promising neutron detector with anticoincidence protection, which is free from this drawback, is presented below.

The article discusses the features of narrow-band processes at the output of the amplitude detector. Much attention is paid to the appearance of phase jumps by π when the signal envelope passes through zero and their disappearance, since the use of this feature allows us to propose a number of methods to increase the noise immunity of receiving devices. The article also uses a mathematical model built in the MATLAB environment to determine the ratio of the signal spectrum to the average frequency, at which the transition of the narrowband process to the wideband process occurs.

Samples of porous silicon carbide were obtained using sucrose or carbon and aerosil or silica mesoporous molecular sieves (SBA-3, SBA-15, KIT-6 and MCF). Fibers content in silicon carbide samples is higher when the mesopore surface area of carbon materials derived from carbon-silica composites is lower. Based on the found correlation between the morphology and porosity of SiC and mesopore surface area of the carbon component in the composites, a templating action of carbon in carbothermal reduction was suggested.

Partly zeolitized micro-mesoporous aluminosilicates SBA-15/ZSM-5 were synthesized by conversion of dry gel of template-containing SBA-15 in the presence of tetrapropylammonium hydroxide. They have a hexagonally ordered mesostructure and developed surface and mesoporosity for which the concentration and strength of the Bronsted and Lewis acid sites are higher than in AlSi-SBA-15. The formation of Bronsted acid sites of moderate strength in the samples with a low degree of zeolitization is due to the presence of ZSM-5 precursors as well as crystallites in the obtained aluminosilicates.

Micro-mesoporous aluminosilicates consisting of agglomerates of the ZSM-5 nanoparticles were obtained using dual-functional templates [C6H13–N+(CH3)2–C6H12–N+(CH3)2–C6H13](Br−)2 (C6–6–6Br2), [C8H17–N+(CH3)2–C6H12–N+(CH3)2–C8H17](Br−)2 (C8–6–8Br2). Aluminosilicates with randomly oriented flake-like particles built from ZSM-5 layers were obtained using [C16H33–N+(CH3)2–C6H12–N+(CH3)2–C6H13](Br−)2 (C16–6–6Br2). Use of С8–6–8Br2 and additive of cetyltrimethylammonium bromide CTAB (CTAB concentration is lower than the first critical micelle concentration, CMC1) leads to an increase of the total specific surface area, mesopore surface area and the mesopore size uniformity in the product, as well as the concentration of Bronsted acid sites accessible for bulk molecules. It is assumed that CTAB role is to limit the zeolite crystals growth. Addition of CTAB to С16–6–6Br2 (CTAB concentration is also lower than CMC1) promotes the formation of micro-mesoporous aluminosilicate possessing disordered lamellar mesostructure stable upon calcination which is characterized by a higher total specific surface area and better mesopores uniformity than ZSM-5 obtained in the presence of С16–6–6Br2. The additive of a molecular template tetrapropylammonium hydroxide (TPAOH) shifts the structure formation toward zeolite and leads to an increase in the ratio of concentrations of Bronsted and Lewis acid sites for the obtained aluminosilicates. The addition of small amounts of TPAOH into the reaction mixture (TPAOH/C16–6–6Br2 = 6.5·10−3) leads to formation of self-pillared aluminosilicate. In this material the nanoparticles act as “pillars” between the layers of ZSM-5 and thus contribute to retention of low-ordered lamellar mesostructure after calcination, leading to increase of the total specific surface area and improving mesopores uniformity.

El factor principal es la orientación a la verdad, como un concepto absolutamente o relativamente estable en la cosmovisión del hombre y la teoría científica; sin embargo, en el más mínimo cambio de esta esfera hacia la ciencia intensiva o en su transición a un nivel diferente de funcionamiento, este especialista no podrá cambiar rápidamente su función profesional y social: por lo tanto, los autores ofrecen el otro concepto del paradigma educativo, dirigido a la comprensión de las disciplinas educativas, generales y profesionales a través de su verdad, y destacando no solo sus características específicas sino también su importancia general en el sistema de ciencias y la cosmovisión del hombre moderno. La pedagogía moderna puede utilizar este enfoque en educación como alternativa.

Samples of crystal modifications of porous silicon carbide were obtained by carbothermal method using carbon precursors (sucrose, carbon) and aerosil or mesoporous silicas molecular sieves SBA-3, SBA-15, KIT-6, and MCF as silicon sources. Porous β-SiC samples obtained from carbon–silica composites are characterized by high structural and sorption characteristics (S BET up to 410 m2/g, V pore up to 1.0 cm3/g). High hydrogen adsorption capacity of silicon carbide samples based on KIT-6 (up to 1.24 wt% at 77 K and 1 atm.), considering low adsorption energy ( $$ \left| {\Delta \mu_{0} } \right|_{{{\text{H}}_{2} }} $$ ) up to 2.3 kJ/mol for SiC vs. ca. 5.0 kJ/mol for carbon), was determined. The highest ever reported value among the existing porous materials was observed for specific adsorption of H2 by SiC (specific adsorption on the pore surface, ρ up to 15 μmol/m2) corresponding to almost complete filling of the surface with hydrogen in the examined conditions (77 K, 1 atm.).

Boron-doped carbon nanostructures were obtained via template and bulk synthesis from sucrose in the presence of boric acid. Synthesized B-containing mesoporous materials are characterized by high spatial ordering, developed surface (up to 870 m2/g), and porosity (up to 1.2 cm3/g). The obtained B-doped microporous materials exhibit high interfacial capacitance (up to 0.36 F/m2), which is higher than the available literature data and enables the use of synthesized samples as materials of supercapacitors. The capacity of electric double layer up to 300 F/g using sulfuric acid as the electrolyte was accumulated on microporous B-doped carbons.

Micro-mesoporous alumosilicates derived from zeolite ZSM-5 were obtained in dual template reaction media and in the presence of dual functional templates. It was shown that aluminosilicates with 0.15-0.25 zeolitization exhibit high catalytic activity in cumene cracking, approaching the activity of ZSM-5 and superior to ZSM-5 in total selectivity relative to the major products (propylene and benzene). Greater oligomerization of propylene is observed with increasing micropore volume and concentration of strong acid sites in the alumosilicates along with increased cumene conversion.

Carrying out the dual template synthesis (in the presence of molecular and micellar templates) in the alkali metal-free reaction media (pH 11.7–12) at a relatively low-temperature hydrothermal treatment (100–120 °C, duration 3–5 days) allowed to obtain micro-mesoporous aluminosilicates combining the properties of zeolite ZSM-5 and mesoporous molecular sieve AlSi-MCM-41. X-ray amorphous sol-precursors of ZSM-5 zeolite obtained by preliminary hydrothermal treatment of alkali metal-free reaction mixture at 160 °C and containing secondary building units of zeolite were used as initial substances for synthesis of micro-mesoporous aluminosilicates. During the joint formation of the structure of zeolite and mesoporous molecular sieve in one reaction mixture and in contiguous conditions close to optimal for their individual formation, composites zeolite/mesoporous molecular sieve were formed. The structural and sorption characteristics and acidity of the obtained composites differ from mechanical mixture of two phases. X-ray amorphous micro-mesoporous aluminosilicate with secondary building units and precursors of ZSM-5 in mesostructure is characterized by higher concentration and strength of Bronsted and Lewis acid sites as well as a higher catalytic activity in the reaction of cracking of cumene compared to AlSi-MCM-41 of similar composition. This aluminosilicate also exhibits a higher total selectivity toward the major products of reaction, in comparison with ZSM-5.

The samples of nonstoichiometric carbon nitride characterized by spatial ordering, large pore volume (up to 0.8 cm3/g) and specific surface area (up to 585 m2/g) were obtained via matrix carbonization of ethylenediamine in the presence of carbon tetrachloride in mesoporous molecular sieves KIT-6 and MCF as exotemplates. In contrast to nitrogen-containing carbons (obtained by modification of carbon samples with nitrogen in the result of compatible thermal treatment of the initial porous carbon with melamine) nonstoichiometric carbon nitride contains much more nitrogen (up to 13.7 wt.% (C/N = 6), compared with preceding 0.6 wt.%) and increased the quantity of basic nitrogen-containing groups (in particular, amino groups)—up to 0.68 mmol/g (vs. 0.46 mmol/g). The increase of adsorption capacity towards hydrogen and carbon dioxide: adsorption potential, differential heat of CO2 adsorption, specific adsorption on the pore surface—from 5.4 to 7.3 μmol H2/m2 and from 2.2 to 5.4 μmol CO2/m2 for carbon and synthesized samples of nonstoichiometric carbon nitride, respectively, due to the incorporation of nitrogen atoms into the carbon framework was noticed.

The aim of this study was to determine the influence of the conditions of low-temperature sequential dual template synthesis of micro-mesoporous aluminosilicates based on precursors of ZSM-5 on their phase composition, structure, sorption properties, and acidity. The methods of X-ray powder diffraction and volumetric adsorption (N2, 77 K) analysis, dynamic light scattering (for characterization of sol-precursors), IR-spectroscopy, energy-dispersive X-ray spectroscopy, scanning and transmission electron microscopy, solid-state 29Si MAS NMR and 29Si{1H} cross-polarization MAS NMR spectroscopy, temperature-programmed desorption of ammonia, ad(de)sorption of pyridine and 2,6-di-tert-butylpyridine with IR-spectral control were used for characterization of the obtained micro-mesoporous aluminosilicates. It was shown that the convergence of compositions of the reaction mixtures and conditions of formation of zeolites and mesoporous molecular sieves, in particular, the use of alkali-free reaction medium and relatively low temperature of hydrothermal treatment (100 °C) allowed to obtain the X-ray amorphous and partially zeolitized micro-mesoporous aluminosilicates. Such aluminosilicates have appropriate structural and sorption properties and the acidity inherent to ZSM-5 and MCM-41, including the Bronsted and Lewis acid sites which are accessible for bulk molecules of organic substances. The possibility of purposeful regulation of characteristics of micro-mesoporous aluminosilicates depending on the conditions of their preparation was confirmed. Herewith the investigated aluminosilicates possess the sorption and acidic properties which are different from the mechanical mixture of two phases.

Information in the literature on methods of preparation, structure, adsorption properties, and physicochemical characteristics of micromesoporous zeolite materials, including hierarchical porosity, has been summarized and analyzed. Special features were noted and promise was indicated for the use of mesoporous zeolites in catalysis, adsorption, and matrices for new micromesoporous materials. Possible directions for further investigation of the physical chemistry of zeolites and micromesoporous zeolite materials were examined.

Structure–property relationships of nanocomposites of multiwall carbon nanotubes (MWCNTs) and polyaniline (PANI) doped with dodecylbenzenesulfonic acid (DBSA) are studied and discussed in terms of contribution of the PANI phase properties. Two phases of PANI-DBSA with different properties, such as a shell-wrapping carbon nanotube and separate neat PANI-DBSA domains, are revealed for the first time in the nanocomposites with a high or medium PANI-DBSA content. In the nanocomposites with lower PANI-DBSA contents (

High structure-directing activity and specificity of templating action of tetrapropylammonium cations TPA+ as well as high concentration of framework-forming substances in the initial reaction mixtures contribute to the formation of zeolite ZSM-5 at relatively low temperature (100 °C) in the alkali-free media. Zeolite ZSM-5 obtained at 100 °C has higher micropore and mesopore volumes, specific surface area, less uniform micropore size distribution in comparison with ZSM-5 synthesized at 170 °C in an alkaline medium in the presence of hydrated Na+ cations. Samples synthesized at 100 °C possess a lower concentration of acid sites and broader distribution of them in strength, compared with ZSM-5 obtained at 170 °C in an alkaline medium. ZSM-5 obtained at 100 °C exhibits a high catalytic activity in the reaction of cracking of cumene, as well as a higher selectivity to propylene and styrene, in comparison with isostructural analogue obtained at 170 °C in an alkaline medium. It is assumed that the investigated alkali-free reaction mixtures and the corresponding sol-precursors of zeolite ZSM-5 containing the elements of secondary building units can be used for obtaining of micro-mesoporous aluminosilicates in the conditions of low-temperature synthesis (100 °C) by dual-template method—in the presence of molecular and micellar templates.

Conditions and peculiarities of matrix and bulk synthesis of carbon nanoporous adsorbents, methods of activation of carbons to produce highly porous samples for application in various fields (adsorption, catalysis, producing the supercapacitors etc.) were analyzed. The available data on the functionalization of nanoporous carbons, particularly through the doping with heteroatoms (N, P, B, etc.) were summarized.

Silicon carbide in the $$ \beta $$ modification with a developed surface and a large pore size was obtained by carbothermal reduction using mesoporous siliceous molecular sieves (SBA-15, KIT-6, MCF, SBA-3). The formation of silicon carbide with high porosity parameters is favored by the use of the KIT-6 mesoporous molecular sieve (MMS) with a three-dimensional structure and a mutually intersecting system of mesopores as matrix, by the close to the stoichiometric C/SiO2 ratio, and also by the higher level of filling with carbon in the pores of the siliceous MMS.

It was established that the mesoporous microspheres with size of about 10 nm formed by anatase nanocrystals exhibit photocatalytic activity in the release of H2 from water–ethanol mixtures and in the gas-phase oxidation of benzene by atmospheric oxygen. They are also active during the generation of current in a photoelectrochemical cell exposed to UV light or in TiO2/CdS heterostructures exposed to visible light. It was shown that the efficiency of the photoprocesses involving the mesoporous microspheres significantly exceeds that of nonporous nanocrystalline Evonik P25 TiO2. Possible reasons for the enhanced photoactivity of the microspheres are discussed.

XRD, TPDA, and IR spectroscopy of pyridine were used to study the effect of the synthesis conditions on the formation, adsorption characteristics, and acid properties of composite micro/mesoporous materials. Spatially well-ordered phases such as MCM-41 and zeolite phases ZSM-5, Beta, and MCM-22 were found to exist in our samples. Variation of the preparation conditions permitted us to regulate the porosity and adsorption characteristics of the composite materials and the type, concentration, and strength distribution of the acid sites in the samples. The strength of the acid sites of the composite micro/mesoporous materials and their concentration are much higher than for mesoporous AlSi-MCM-41 but somewhat less than in the initial zeolites. Analysis of the results suggested that the samples obtained under similar conditions are not ordinary mechanical mixtures of two phases (zeolite and AlSi-MCM-41), but rather unique composites with tightly bound nanoparticles due to formation in a single reaction medium.

We have established that a typical feature of adsorption processes involving participation of porous ionic crystalline compounds formed by cations of bis-macrocyclic copper(II) complexes is absorption/desorption hysteresis, associated with significant rearrangement of the lattices of the complexes during adsorption/desorption. The compounds studied have high sorption capacity for water and methanol, comparable with that of porous coordination polymers.

The comparative research of bulk carbonization of sucrose at different temperatures (Ar, 400–900 °C) in the presence of activating agents (H 3 PO 4 and ZnCl 2 ) and water vapor was carried out. X-ray diffraction, nitrogen and hydrogen adsorption and IR spectroscopy were used for investigating of the structural and sorption characteristics of the obtained materials. It was shown that in conditions of non-catalytic bulk carbonization of sucrose homogeneous microporous carbons were formed; with the increasing of the temperature of carbonization micropore volume and adsorption of hydrogen (up to 1.48 wt.%, 900 °C) were increased. The essential effect of using an activating agent and/or catalytic agent on the porous structure of carbons: in the presence of phosphoric acid carbons with increased micro- and supermicropore volume were obtained. Mainly mesoporous carbons were formed in the presence of zinc chloride. It was established that thermal activation with steam at 800 and 850 °C results in the significant increase of specific surface area of the carbons ( S BET – up to 2287 m 2 /g) and hydrogen adsorption – up to 1.88 and 1.99 wt.% accordingly.

Partially zeolitized micro-mesoporous materials (the total specific surface area S BET = 460–645 m2/g, mesopore volume V meso = 0.30–0.57 cm3/g, mesopore diameter D meso ≈ 5.6 nm, micropore volume V micro = 0.11–0.16 cm3/g, micropore diameter D micro ≈ 0.72 nm) and X-ray amorphous micro-mesoporous materials with uniform mesoporous structure (mesopore specific surface area S meso = 820–890 m2/g, total pore volume V t = 0.71–0.86 cm3/g, V meso = 0.53–0.67 cm3/g, D meso = 1.8–2.4 nm) were obtained by micellar templating of sol-precursor containing primary products of crystallization of zeolite BEA under conditions typical for forming of mesoporous molecular sieve MCM-41 (hydrothermal treatment at 100–130 °C for 3–5 days). It was found that the obtained X-ray amorphous micro-mesoporous materials contain secondary building units of zeolite BEA (five-membered rings of Si–O tetrahedra of BEA) and show acidic properties comparable to zeolite BEA.

Sulfonation of mesoporous organosilicas with diethylxylene bridging groups using chlorosulfonic acid gave mesoporous silicas with arylsulfonic acid bridging groups. TPD-MS was used to confirm the structure and characterize the thermal stability of the organic groups of the starting and sulfonated samples. The catalytic activity of mesoporous silicas with arylsulfonic acid bridging groups in the synthesis of ethyl tert-butyl ether is higher than for model samples (MCM-41 mesoporous molecular sieves and silica gel with anchored alkylsulfonic acid groups as well as SiO2/Nafion nanocomposite) and is similar to the activity of industrial catalysts such as Amberlyst-15.

We have shown that varying the substituents in the cationic component of porous crystal compounds formed by azamacrocyclic nickel(II) complexes and the 1,3,5-benzenetricarboxylate anion has a substantial effect on their adsorption behavior relative to water, methane, and n-hexane vapor. The studied compounds are characterized by reversibility of the changes in the crystal lattices during adsorption/desorption, stoichiometry of the reaction with water vapor with relatively low and hydrolytic stability at high humidity.

We have used a dual template synthesis method based on an initial ZSM-5 zeolite sol precursor in the presence of molecular and micellar templates to obtain X-ray amorphous and zeolite-containing microporous/mesoporous aluminosilicates having an ordered MCM-41 mesostructure, extended mesoporosity, small micropore volume, and medium-strength acid sites. We note a deviation from additivity for the change in micropore volume and the concentration of acid sites in the synthesized zeolitized samples.

The results of spectral (UV–vis), morphological (XRD, SEM), and current–voltage investigations of a nanostructured layer of ZnO electrodeposited on the surface of an ITO electrode are presented. The possibility of using tetraalkylammonium hydroxides (TAAH) as organic templates as an alternative to widely used templates such as eosin Y or coumarin was demonstrated for the first time. It was established that the spectral and electrophysical characteristics of the nanostructured ZnO layers synthesized in the presence of eosin Y and TAAH are close, which confirms the suitability of TAAH as template.

In this work we find that polyaniline (PANI), synthesized by aniline chemical polymerization at a surface of template polycarbonate (PC) particles, is significantly different in molecular weight, structural order, oxidation state, and conductivity from a neat PANI. Molecular weight of the PANI phase in the composite (Mw = 158,000) is 1.6 times higher than that of the neat PANI synthesized in the absence of the template particles. Moreover, XRD analysis shows that crystallinity of the PANI phase in the composite is three times higher than that of the neat PANI. Raman spectroscopy indicates that the oxidation level of PANI in the PC/PANI composite is lower than that of the neat PANI. These noticeable changes of the PANI phase properties suggest specific interactions of reagents in the polymerization medium and formed PANI with the template phase as well as an orientation effect of the latter surface. FTIR spectroscopy reveals that hydrogen bonding in the neat doped PANI is weaker than one between -NH- of PANI and C═O of PC at their interface. The discovered differences are supported by the fact that conductivity of the PANI phase in the composite is more than three times higher than that of the neat PANI.

Thermally stable mesoporous nanocrystalline ТiО2 with a pure anatase structure was obtained by sol–gel synthesis (in combination with hydrothermal treatment) using titanium tetrabutoxide and dibenzo-18-crown-6 as a structure-directing agent in presence of surfactant and/or La3+ ions additives. Nanocrystalline TiO2 demonstrates various textures with a well-defined spherical morphology (micro- and nanospheres), a crystallite size of no greater than 10 nm (XRD), and a narrow pore size distribution. Spherical particles of micrometer scale in the presence of La3+ ions do not form. TiO2 calcined (at 500 °C) after hydrothermal treatment (at 175 °C) has a significantly more developed porous structure as compared with TiO2 which was not treated hydrothermally. For example, specific surface area amounts 137 m2 g−1 and 69 m2 g−1, pore volume 0.98 cm3 g−1 and 0.21 cm3 g−1, pore diameter 17.5 nm and 12.5 nm respectively for samples hydrothermally treated and not treated.

A comparative study was carried out on the adsorption of H2, N2, CH4, CO, and CO2 at 77-273 K (p ≤ 1 atm) by silicate and phosphate zeolites and carbon materials, varying in size, shape, volume, and distribution of the micro- and mesopores. We studied effects of the porosity parameters and nature of the surface on gas absorption, in particular, the increased selectivity related to restrictions in the zeolite micropores, the presence of the cationic and acid protic sites as well as decreasing size of the micropores in the carbon adsorbents. The greatest separation of the methane-containing gas mixtures was found for zeolites with MFI channel structures. The greatest separation of the hydrogen-containing mixtures was found for cavity-type LTA, FAU, and CHA zeolites.

Titanosilicate composite catalysts were synthesized from inorganic and elementorganic titania precursors and nanostructurized silicas as substrate by chemical liquid-phase deposition approach or from soluble titania and silica precursors by sol-gel process. The nature of TiO 2 precursors and silica substrate affect by a level of intercomponent interactions (because of a formation of Si-O-Ti bonds was identified) and structurization of surface active layer of the catalysts. Phase structure and porosity of the composites could be regulated by changing a composition and synthesis conditions. Applying the different synthetic approaches the catalysts with meso- or microporous structures were prepared. From UV-DRS analysis it was found that TiO 2 surface layer of the composites consists of as catalytically active tetracoordinated titanium sites (λ abs ∼ 200 nm) as well as low active pentacoordinated (λ abs ∼ 225 nm) and hexacoordinated titanium atoms (λ abs ∼ 245 nm). A relative ratio of the titanium sites could be controlled by selecting a nature of silica substrates. Efficiency of titanosilicate catalysts obtained was demonstrated in a reaction of liquid-phase oxidation of allyl alcohol by aqueous hydrogen peroxide. The yield of glycidol in the process reaches 25 %. Among other products the hydroxyl-and carboxyl-containing compounds are detected.

Phosphorus-containing carbon porous materials were obtained by pyrolysis of sucrose in the presence of phosphoric acid at a temperature 400 and 800 °C. Synthesized samples were characterized by elemental analysis, infrared spectroscopy, nitrogen adsorption–desorption, the measurement of cation-exchange capacity (CEC) and sorption capacity for lead ions, potentiometric titration. It was shown that phosphorus-containing carbon sorbents have acidic properties and they are characterized by high cation-exchange capacity (up to 5.9 mmol/g). The samples which were synthesized at 800 °C have the highest content of acid groups, as well as phosphorus and oxygen. Detected surface acidic groups are phosphorus-containing (pК ~1.7–1.9) and represent residua of acid phosphates and polyphosphates, connected with carbon framework. High CEC of synthesized materials can be attributed to a significant degree of phosphorylation of sucrose through the large number of hydroxyl groups. P-containing acid groups on the surface of carbon framework provide high adsorption of heavy metals ions (in particular lead). Thus, the obtained P-containing carbon sorbents can be used as effective cation-exchangers for the removal of cations of heavy metals from aqueous solutions.

Comparative research of matrix and bulk carbonization of some organic precursors (sucrose, acetonitrile) in silica mesoporous materials SBA-15 and KIT-6 was conducted. X-ray diffraction, nitrogen adsorption analysis, Raman spectroscopy were used for determination of the structural-sorption characteristics of the obtained materials. It was shown that the carbon mesoporous materials CMK-8 obtained in the mesopores of KIT-6 had higher adsorption characteristics because of features of three-dimensional cubic structure, larger pore volume and framework’s wall thickness. It was established that partially graphitized spatially well-organized carbon materials were formed as a result of pyrolysis of acetonitrile in the silica matrices SBA-15 and KIT-6. It was conditioned by the absence of considerable spatial limitations for growth of graphite structures on the initial stage of the synthesis when the pores of the matrix were not filled up with the organic precursor. Product of bulk carbonization of sucrose is compact carbon microporous framework with low sorption characteristics (micropore volume is 0.09 cm3/g).

Thermal decomposition of the trinuclear heterometallic oxoacetates [Fe 2 M(μ 3 -O)(CH 3 COO) 6 (H 2 O) 3 ] has been used as a single-precursor method for synthesis of the spinel-structured ternary oxides MFe 2 O 4 (M = Mn II , Co II , and Ni II ). This facile process occurring at 320 °C results in the formation of nanocrystalline (7–20 nm) highly pure stoichiometric ferrites in quantitative yield. The magnetic properties of these nanoparticulate ferrites were studied in the 10–300 K temperature range, revealing superparamagnetic behavior for the Ni and Mn particles and ferrimagnetic behavior for the Co ones at room temperature. Their blocking temperatures follow the order: CoFe 2 O 4 > MnFe 2 O 4 > NiFe 2 O 4 .

Porous organosilicas with 1.5–100 mol.% of bridging 1,5-bis-(2′-ethyl)-xylene (BDEX) groups were synthesized by a template-directed procedure and characterized using FTIR spectroscopy, temperature programmed desorption mass-spectrometry, X-ray diffraction and methanol adsorption. The formation of dually porous structure, consisted in small low-ordered mesoporous (2–3 nm) MCM-41 type particles united in aggregates with wide interparticle pores (8–20 nm), was found. If the concentration of the BDEX groups is smaller than 10 mol.%, the BDEX groups can be thermally oxidized without dually porous structure damage. The aggregation of the primary particles by chemical cross-linking is an alternative way to form a network of large so-called “transport” pores in the mesoporous material.

Na + complex with the dibenzo-18-crown-6 ester was used as a template to synthesize mesoporous titanium dioxide with the specific surface area 130–140 m 2 /g, pore diameter 5–9 nm and anatase content 70–90%. The mesoporous TiO 2 samples prepared were found to have photocatalytic activity in Cu II , Ni II and Ag I reduction by aliphatic alcohols. The resulting metal–semiconductor nanostructures have remarkable photocatalytic activity in hydrogen evolution from water–alcohol mixtures, their efficiency being 50–60% greater than that of the metal-containing nano-composites based on TiO 2 Degussa P25. The effects of the thermal treatment of mesoporous TiO 2 upon its photocatalytic activity in hydrogen production were studied. The anatase content and pore size were found to be the basic parameters determining the photoreaction rate. The growth of the quantum yield of hydrogen evolution from TiO 2 /Ag 0 to TiO 2 /Ni 0 to TiO 2 /Cu 0 was interpreted in terms of differences in the electronic interaction between metal nanoparticles and the semiconductor surface. It was found that there is an optimal metal concentration range where the quantum yield of hydrogen production is maximal. A decrease in the photoreaction rate at further increment in the metal content was supposed to be connected with the enlargement of metal nanoparticles and deterioration of the intimate electron interaction between the components of the metal–semiconductor nanocomposites.

Zeolite IPC-3 — which is isostructural with the extra-large pore germanate zeolite ASU-16 — and its Si, Al and Ti forms were synthesized using 1,6-diaminohexane as the template. It was established that the Si atoms occupy the tetrahedral positions in the IPC-3 framework, the Al atoms occupy the octahedral or tetrahedral positions and the Ti atoms the octahedral positions. The germanate zeolite IPC-3 and Si-, Al- and Ti-IPC-3 are stable up to 200–300°C. Despite the presence of the template, which stabilizes the framework of IPC-3, the adsorption capacities of samples previously degassed at 200°C were up to 0.13 cm 3 /g.

(ML)2(bipy) complexes (LH2 = thiosemicarbazone of 2-hydroxybenzaldehyde, bipy = 4,4′-bipyridine, M = Ni(II), 1, or Cu(II), 2) were synthesized and characterized by X-ray crystallography. Compound 1 possessed porous structure due to peculiarities of crystal packing, whereas 2 formed infinite zig-zag chains with dense non-porous packing. It was shown that 1 absorbed 0.013 cm3/g of methanol vapor in two steps. Complex 1 was diamagnetic; for 2, the dependency of χ versus T could be interpreted by Bleaney–Bowers expression in 20–300 K temperature range (J = −6.8 cm−1, g = 2.07).

Microporous, mesoporous, and new hybrid materials were studied in verbenol oxide isomerization for the synthesis of biologically active substance with anti- Parkinson activity. H-Si-MCM-41, H-Al- MCM-41, H- Al- MCM-48, H-Beta-25, and H-Beta-300 were compared with hybrid materials. The latter with a zeolite-like micromesoporous structure were characterized and evaluated for their catalytic activity for the first time. The approach of dual templating for synthesis of new materials was applied in this work to combine properties of Beta-zeolites and mesoporous cellular foams (MCF). The selectivity to the target product was the highest over microporous mild acidic H-Beta- 300 and hybrid ZF-100, with also mild acidity and even absence of strong acid sites. Selectivity at 97 and 99% of conversion was 61 and 59% for H-Beta-300 and hybrid ZF-100, respectively.

Porous magnetic composites were prepared by the synthesis of molecular sieve MCM-41 in the presence of Fe{sub 3}O{sub 4} nanoparticles with average diameter of 15 nm. Nanoparticles were captured by porous silica matrix MCM-41, which resulted in their incorporation, as it was confirmed by TEM, SEM and X-ray diffraction. The materials possessed high surface area (392-666 m{sup 2} g{sup -1}), high pore volume (0.39-0.73 cm{sup 3} g{sup -1}) along with high magnetic response (M {sub S} up to 28.4 emu g{sup -1} at 300 K). Calcination of samples resulted in partial oxidation of Fe{sub 3}O{sub 4} to {alpha}-Fe{sub 2}O{sub 3}. The influence of nanoparticles content on sorption and magnetic properties of the composites was shown. No hysteresis was found for the samples at 300 K; at 5 K, H {sub C} was in the range 370-385 G for non-calcinated samples and 350-356 G for calcinated ones. - Graphical abstract: Schematic presentation of MCM-41/Fe{sub 3}O{sub 4} composite.

Optically transparent, crack-free mesoporous titania and zirconia-doped titania thin films were fabricated by the sol—gel technique using the non-ionic amphiphilic triblock copolymer Pluronic P123 as the template. The structure and optical properties of these films were characterized using TEM, low-angle XRD, DTA/TG measurements, UV—vis spectroscopy and hexane adsorption investigations. It was found that addition of ZrO2 into the TiO2 matrix retarded sintering of the films, thereby increasing the specific surface area after treatment up to 500°C. The catalytic activity of the mesoporous TiO2 and TiO2/(5–30%) ZrO2 films in ethanol photo-oxidation increased with increasing specific surface area and surface acidity of the samples.

Reaction of TiF4 and 18-crown-6 in MeCN affords the molecular complex [(cis-TiF4)2(18-crown-6)] (1) only. Water and THF displace the 18-crown-6 in the tetrafluoro complex 1, with the formation of cis-TiF4L2. The complex cis-TiF4(H2O)2 and 18-crown-6 form [{cis-TiF4(H2O)2}2(18-crown-6)] (2), in which cis-TiF4(H2O)2 and 18-crown-6 are connected by hydrogen bonding through the protons of coordinated H2O in TiF4(H2O)2 and the oxygen atoms of the crown ether. Complexes 1 and 2 were characterized by X-ray single crystal analysis, elemental analysis, IR, NMR and Mass spectroscopy. The relative basicities of the 18-crown-6 and the molecular donor ligands MeCN, THF, H2O toward TiIV fluoride were established by NMR spectroscopic investigations of the substitution reactions. 18-crown-6 is slightly more basic than MeCN, similar to that of Et2O, and less basic than THF and H2O. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)