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Considering the vast importance of peptide and protein interactions with inorganic surfaces, probing hydrogen bonding during their adsorption on metal oxide surfaces is a relevant task that could shed light on the essential features of their interplay. This work is devoted to studying the dipeptides' adsorption on anatase nanoparticles (ANs) in light and heavy water to reveal differences arising upon the change of the major hydrogen bonding carrier. Thermodynamic study of six native dipeptides' adsorption on ANs in both media shows a strong influence of the solvent on the Gibbs free energy and the effect of side-chain mobile protons on the entropy of the process. The adsorption is endothermic irrespective of the medium and is entropy-driven. Computer simulations of peptide adsorption in both media shows similarity in binding via an amino group and demonstrates structural features of protonated and deuterated peptides in obtained complexes. Calculated peptide- anatase nanoparticle (AN) descriptors indicate surface oxygens as points of peptide-nanoparticle contacts.

Ionothermal synthesis of carbon nitride paved the way to a new structural allotrope—polytriazine imide. In this work, we screen available precursors for pristine polytriazine imides and for their graphitic analogs narrowing it to the melamine—urea mixture as the most promising starting material. Photocatalytic activity of materials verified in reaction of benzyl alcohol oxidation to benzaldehyde, which is known to be highly requested chemical with thousands of tons of annual production. Therefore "green" and selective route of production is highly desired. Developed PTI-LiCl was tested for selective photooxidation of benzyl alcohol to benzaldehyde, demonstrating precious conversion and selectivity rates—96.3% and 91.6%, respectively after 5 hours of UV irradiation. Detailed physical-chemical characterization revealed that PTI materials possessed more ordered and highly condensed structure which grant them improved photocatalytic properties in comparison to graphitic carbon nitride polymorph. Graphical abstract represents two different lines of materials which are known to be various polymorphs of carbon nitride studied comparatively in the present work. One of them is convenient graphitized carbon nitride which is prepared from precursors (melamine, urea or thiourea) via the simple thermal treatment. Another line of materials are prepared via thermal treatment in the eutectic mixture of molten salts. The later line of materials is more active in selective photocatalytic oxidation of benzyl alcohol.

For the first time, a simple and sensitive electrochemical sensor based on a screen printed electrode (SPE) modified with titanium dioxide (TiO

The article deals with the problem of organizing the group movement of marine robotic systems autonomous underwater vehicles (AUV), in a priori unknown environment with obstacles. The presence of numerous studies in this area confirms the relevance of this problem. The proposed method of planning the movement of the group is based on a combined approach, which organizes a multi-level approach to the organization of the movement of marine robotic complexes (MRC). At the upper level, a global planning system based on the randomized tree method is developed and provides for the overall movement of the group, while the lower-level planning system allows objects to plan the movement and interaction of objects in the group at the local level, including allowing for trouble-free movement of objects in space. The optimization problem is calculated on all stages of the band, starting with the process, optimizing group of MRC, ending the ongoing process of minimizing the total distance between the target point and the location of the formation. Completed numerical simulation of the movement of a group of four AUV in an unknown environment with stationary obstacles is carried out. In the end, we consider the results of the proposed method and its further development, in particular its application in the three-dimensional problem statement.

Fundamentals of inorganic-organic interactions are critically important in the discovery and development of novel biointerfaces amenable for utilization in biotechnology and medicine. Recent studies indicate that proteins interact with surfaces through limited adsorption sites. Protein fragments such as amino acids and peptides can be used for interaction modeling between complex biological macromolecules and inorganic surfaces. During the last three decades, many valid and sensitive methods have been developed to measure the physical chemistry fundamentals of those interactions: isothermal titration calorimetry (ITC), surface plasmon resonance (SPR), quartz crystal microbalance (QCM), total internal reflection fluorescence (TIRF), and attenuated total reflectance spectroscopy (ATR). The simplest and most affordable technique for the measurement of adsorption is the depletion method, where the change in sorbate concentration (depletion) after contact with solution-dispersed sorbent is calculated and assumed to be adsorbed. Adsorption isotherms based on depletion data provide all basic physicochemical data. However, adsorption from solutions requires longer equilibration times due to kinetic restrictions and sorbents with a high specific surface area, making it almost inapplicable to macroscopic fixed plane surfaces. Moreover, factors such as the instability of sols, nanoparticle aggregates, sorbent crystallinity, nanoparticle size distribution, pH of the solution, and competition for adsorption, should be considered while studying adsorbing peptides. Depletion data isotherm construction provides comprehensive physical chemistry data for literally every soluble sorbate yet remains the most accessible methodology, as it does not require expensive setups. This article describes a basic protocol for the experimental study of peptide adsorption on inorganic oxide and covers all critical points that affect the process.

For the first time, a simple and sensitive electrochemical sensor based on a screen printed electrode (SPE) modified with titanium dioxide (TiO2) and polytriazine imide submicrostructured composite (TiO2-PTI) has been developed for the simultaneous detection of fipronil (FIP) and its toxic metabolite fipronil sulfone (FIP-S). The submicrostructured composite material based on TiO2 and PTI was obtained by simple hydrothermal treatment of the Ti peroxocomplexes in the presence of pristine. This carbon nitride allotrope has better crystallinity and conductivity than its graphitic analog. It was found that the TiO2-PTI submicrostructured composite enhanced the electrochemical sensing of the SPE electrode towards FIP and its metabolite FIP-S in 0.1 M Britton-Robinson buffer (pH 10) at the oxidation potentials of 0.82 V and 0.94 V, respectively. In addition, it showed good stability and reproducibility for the determination of both analytes. Under optimal conditions, the peak currents by square wave voltammetry were found to vary linearly with FIP and FIP-S concentrations in the range from 0.01 to 10 μM and from 10 to 50 μM, with a detection limit of 8.42 nM, 3.6 μg/kg for FIP and 9.72 nM, 4.04 μg/kg for FIP-S. This sensor was successfully used to detect FIP and FIP-S in eggs and water samples with good recoveries of 90%–106.6%, which was validated by liquid chromatography tandem mass spectrometry.

The affinity of biomolecules, such as peptides and proteins, with inorganic surfaces, is a fundamental topic in biotechnology and bionanotechnology. Amino acids are often used as “model” bits of peptides or proteins for studying their properties in different environments and/or developing functional surfaces. Despite great demand for knowledge about amino acid interactions with metal oxide surfaces, studies on the issue represent a fragmentary picture. In this paper, we describe amino acid adsorption on nanocrystalline anatase systematically at uniform conditions. Analysis of the Gibbs free adsorption energy indicated how the aliphatic, aromatic, polar, and charged side chain groups affect the binding affinity of the amino acids. Thermodynamic features of the L-amino acid adsorption receive thorough interpretation with calculated molecular descriptors. Theoretical modelling shows that amino acids complex with TiO2 nanoparticles as zwitterions via ammonium group., This work was financially supported by the Russian Foundation for Basic Research (grant no. 15-03-07834-a). I.K. acknowledge the financial support from Spanish MINECO (CTQ2014-52956-C3-1-R and MAT2016-78155-C2-1-R).

The C-N samples were synthesized at 500 °C from melamine and four kinds of pitch. At 50–100 mass % of pitch all samples were single phase nitrogen solid solutions in graphitic carbon. Maximal detected concentration of 22.4 mass % N correspond to solid solution with formula C100H26.8N26.3O3.1. According to infrared spectroscopy the N atoms chaotically substitute carbon. The electric resistivity of samples with 22.4 mass % N was 1.3–67 Ω ∗ m, which is 100–1000 times lower than resistivity of corresponding graphitic carbon without doping (430–6700 Ω ∗ m). The resistivity of graphitic C3N4 is about 1011 Ω∗m.

R.S. Morozov1, yanatulskoi@mail.ru V.V. Avdin1, v.avdin@mail.ru I.V. Krivtsov1,2, zapasoul@gmail.com A.A. Gorshkov1, olengor14@gmail.com A.V. Urzhumova1, anna.urzhumova7@yandex.ru A.V. Osinskaya1, alex.osinskaya@gmail.com D.S. Yuzhalkin1, daniliyc@gmail.com 1 South Ural State University, Chelyabinsk, Russian Federation 2 Department of Organic and Inorganic Chemistry, University of Oviedo-CINN, Oviedo, Spain Морозов Роман Сергеевич – инженер НОЦ «Нанотехнологии», Южно-Уральский государственный университет. 454080,г. Челябинск, пр. Ленина 76. E-mail: YAnatulskoi@mail.ru Авдин Вячеслав Викторович – доктор химических наук, заведующей кафедрой «Экологии и химической технологии», химический факультет, Южно-Уральский государственный университет. 454080, г. Челябинск, пр. Ленина, 76. E-mail: avdinvv@susu.ru Кривцов Игорь Владимирович – кандидат химических наук, инженер-исследователь НОЦ «Нанотехнологии», Южно-Уральский государственный университет. 454080, г. Челябинск, пр. Ленина, 76. Факультет органической и неорганической химии, Университет Овьедо-CINN, Овьедо, Испания. E-mail: zapasoul@gmail.com Горшков Александр Андреевич – студент, Южно-Уральский государственный университет. 454080, г. Челябинск, пр. Ленина, 76. E-mail: olengor14@gmail.com Уржумова Анна Викторовна – студент, Южно-Уральский государственный университет. 454080, г. Челябинск, пр. Ленина, 76. E-mail: anna.urzhumova7@yandex.ru. Осинская Александра Витальевна – магистр, Южно-Уральский государственный университет. 454080, г. Челябинск, пр. Ленина, 76. E-mail: alex.osinskaya@gmail.com Южалкин Даниил Сергеевич – магистр, Южно-Уральский государственный университет. 454080, г. Челябинск, пр. Ленина, 76. E-mail: danili-yc@gmail.com

Surface properties of the nanostructured materials are essential in attaining particular functionality, which is why there are a plethora of surface modification methods applied during or past the synthesis of nanoparticular substrates. Depending on the resulting content of the surface it could be heterophase forming modifications or pristine titania modifications. In this communication, we study a novel approach to pristine titania surface alteration by controlled chemisorption of the stable water-soluble titanium complex on the nanocrystalline anatase. Following on-air calcination for removal of organic residues converts chemisorbed complexes into oxide phase increments. Such an approach retains crystallinity and specific surface with simultaneous withdrawal of surface hydroxyl groups.

O.I. Bol’shakov1, bolshakovoi@susu.ru V.A. Potemkin1, potemkinva@susu.ru M.A. Grishina1, grishinama@susu.ru A.S. Galushko2, galas74@inbox.ru S.V. Merzlov1, bostonbruins.2011.6@gmail.com R.S. Morozov1, yanatulskoi@mail.ru A.O. Shchelokov1, artyom.shchelokov@yandex.ru V.V. Popov3, Popov.ioc@gmail.com 1 South Ural State University, Chelyabinsk, Russian Federation 2 Institute of Organic Chemistry of the Russian Academy of Sciences, Moscow, Russian Federation 3 Wayne State University, Detroit, MI, USA Большаков Олег Игоревич – кандидат химических наук, научный сотрудник Управления научной и инновационной деятельности, Южно-Уральский государственный университет. 454080, г. Челябинск, пр. им. В.И. Ленина, 76. E-mail: bolshakovoi@susu.ru Потемкин Владимир Александрович – научный сотрудник Управления научной и инновационной деятельности, Южно-Уральский государственный университет. 454080, г. Челябинск, пр. им. В.И. Ленина, 76. E-mail: potemkinva@susu.ru Гришина Мария Александровна – главный научный сотрудник Высшей медико- биологической школы, Южно-Уральский государственный университет. 454080, г. Челябинск, пр. им. В.И. Ленина, 76. E-mail: grishinama@susu.ru Галушко Алексей Сергеевич – аспирант лаборатории металлокомплексных и наноразмерных катализаторов (№ 30), Институт органической химии им. Н.Д. Зелинского, РАН. 119991, г. Москва, Ленинский пр. 47. E-mail: galas74@inbox.ru Мерзлов Сергей Владимирович – инженер кафедры экологии и природопользования, химический факультет, Южно-Уральский государственный университет. 454080, г. Челябинск, пр. им. В.И. Ленина, 76. E-mail: bostonbruins.2001.6@gmail.com Морозов Роман Сергеевич – аспирант кафедры экологии и природопользования, Южно- Уральский государственный университет. 454080, г. Челябинск, пр. им. В.И. Ленина, 76. E-mail: yanatulskoi@mail.ru Щелоков Артем Олегович – студент кафедры химической технологии, Южно-Уральский государственный университет. 454080, г. Челябинск, пр. им. В.И. Ленина, 76. E-mail: artyom.shchelokov@yandex.ru Попов Вадим Владимирович – постдокторант факультета биомедицинской инженерии, Университет Уэйна, Wayne State University, 42. W. Warren Ave. Detroit, MI 48202, MI, USA. E-mail: popov.ioc@gmail.com Affinity characteristics of biomolecules, such as peptides and proteins, towards inorganic surfaces in general and to titanium oxide in particular become crucial in biotechnology and bionanotechnology. Amino acids are often used as “model” bits of peptides or proteins for studying their properties in different environments, and/or developing functional surfaces. Despite the great demand for knowledge about amino acid interactions with metal oxide surface, studies on the issue lack in consistency and represent a fragmentary picture. This paper is an attempt to study amino acid adsorption on nanocrystalline anatase systematically at uniform conditions. Features of the L-alanine adsorption have been revealed and interpreted with quantum-chemical calculations. Особенности взаимодействия биомолекул, таких как протеины и пептиды с неорганическими поверхностями вообще и с оксидом титана в частности становятся ключевым фактором биотехнологии и бионанотехнологии. Аминокислоты часто используются в качестве модельных фрагментов пептидов и протеинов для изучения их свойств в различных средах и при изучении новых поверхностей. Несмотря на высокий запрос на фундаментальные представления о взаимодействии биомолекул с поверхностью оксида титана, знания в этой области представлены фрагментарно и не дают целостной картины. В этой статье проведена попытка изучения сорбции аминокислот на оксиде титана в унифицированных условиях. Сорбция L-аланина была интерпретирована квантово- механическим моделированием. The reported study was funded by RFBR according to the research project № 15-03-07834-a.

The affinity of biomolecules, such as peptides and proteins, with inorganic surfaces, is a fundamental topic in biotechnology and bionanotechnology. Amino acids are often used as "model" bits of peptides or proteins for studying their properties in different environments and/or developing functional surfaces. Despite great demand for knowledge about amino acid interactions with metal oxide surfaces, studies on the issue represent a fragmentary picture. In this paper, we describe amino acid adsorption on nanocrystalline anatase systematically at uniform conditions. Analysis of the Gibbs free adsorption energy indicated how the aliphatic, aromatic, polar, and charged side chain groups affect the binding affinity of the amino acids. Thermodynamic features of the l-amino acid adsorption receive thorough interpretation with calculated molecular descriptors. Theoretical modeling shows that amino acids complex with TiO

This article describes the problem of organizing heterogeneous information systems interaction. Various factors influencing the process of intersystem integration are observed. Modern technologies for intersystem integration are considered. A simple and effective approach to arrangement of intersystem integration is offered.

Composite microporous SiO2-TiO2 spheres and micro/mesoporous TiO2 spheres were prepared via the template-free two-step synthetic route using aqueous peroxotitanate solution and tetraethyl orthosilicate (TEOS) as precursors. Both the composite SiO2-TiO2 and pure TiO2 spheres prepared by the solvent-exchange method were initially non-porous, but the applied reflux treatment in water-ethanol suspension successfully transformed them into microporous materials with high apparent surface areas approaching 500 m2·g− 1 and the micropore volume of 0.17 cm3·g− 1, while maintaining the same morphology. The prepared composites retained high values of pore volume and specific surface area up to 400 °C of thermal treatment temperature. The crystallization of TiO2 into the anatase phase in the mixed oxide occurred only at 700 °C, that process was also accompanied by the significant reduction of pore volume, as well as apparent surface area values. The prepared materials were tested as adsorbents for the lead(II) removal; they demonstrated high adsorption capacities, reaching 340 mg(Pb2 +)·g− 1. Moreover, the mixed silica-titania oxide was found to be more efficient adsorbent at low pH values., South Ural State University is grateful forfinancial support of theMinistry of Education and Science of the Russian Federation (grant No16.2674.2014/K). University of Oviedo gratefully acknowledgesfi-nancial support from the Spanish MINECO (MAT2013-40950-R andMAT2016-78155-C2-1-R). Igor Krivtsov thanks for the support theRussian Foundation for Basic Research 16-29-10757-ofi.

Composite silica–titania spherical particles, from the nanometer to submicron size, have been synthesized via a new template-free method, being achieved by the reaction of aqueous titanium peroxo complex with TEOS (tetraethylorthosilicate) in aliphatic alcohols. The choice of the solvent greatly affects the growth of silica–titania particles. It has been established that size of the spheres increases as carbon chain length of alcohol extends (from methanol to n-propanol). The nanometer size SiO2–TiO2 spheres with mean diameter of about 50 nm are formed in the methanol solution, while n-propanol promotes particle growth up to 400 nm. The synthesized composites retain amorphous structure up to 500 °C due to the formation of Si–O–Ti heterolinkages, whose presence has been confirmed by FTIR and XPS studies., South Ural State University is grateful for financial support of the Ministry of Education and Science of the Russian Federation (grant No 16.2674.2014/K). University of Oviedo gratefully acknowledges financial support from the MINECO (MAT2013-40950-R) and FEDER-FICyT (GRUPIN14-060). IK thanks for the support the Russian Foundation for Basic Research13-03-12188-ofi.