1H-Benzotriazol-1-yl 4-{(E)-[4-(dimethylamino) phenyl]diazenyl}benzoate

The title compound, C21H18N6O2, was obtained as a by-product of a reaction between (E)-4-(4-dimethyl­amino­phenyl­azo)benzoic acid and 2-amino-4-(2-pyrid­yl)-6-(6-pyrid­yl)-1,3,5-triazine, which has a very low solubility, under peptidic coupling conditions, using THF as solvent. The condensation reaction occurred between 1-hy­droxy­benzotriazole and (E)-4-(4-dimethyl­amino­phenyl­azo)benzoic acid. The dihedral angle between the benzene rings in the (E)-diphenyl­diazene fragment is 10.92 (13)° and that between the benzotriazole mean plane and the central benzene ring is 80.57 (7)°. In the crystal, [[pi]] - [[pi]] stacking [centroid-centroid distances = 3.823 (2) and 3.863 (2) Å] of similar fragments generates mol­ecular layers parallel to (0-12). The crystal packing also features weak C-H [...] N hydrogen bonds involving N atoms of the benzotriazole ring

Practical book on biology

УЧЕБНО-МЕТОДИЧЕСКИЕ ПОСОБИЯПРАКТИКУМЫБИОЛОГИЯИНОСТРАННЫЕ СТУДЕНТЫДОВУЗОВСКАЯ ПОДГОТОВКАКЛЕТКИРАЗМНОЖЕНИЕНАСЛЕДСТВЕННОСТЬИЗМЕНЧИВОСТЬ ГЕНЕТИЧЕСКАЯВИРУСЫБАКТЕРИИВОДОРОСЛИЛИШАЙНИКИГРИБЫРАСТЕНИЯЖИВОТНЫЕЧЕЛОВЕКА РАЗВИТИЕМОРФОГЕНЕЗВ практикуме рассматриваются сущность жизни, уровни организации живого, биология и физиология клетки, размножение организмов, индивидуальное развитие, наследственность и изменчивость, вирусы, бактерии, водоросли, лишайники, грибы, растения, животные, особенности строения и физиологии человека. Пособие включает 34 темы практических и 5 итоговых занятий. Каждое практическое занятие состоит из вводной части материала, цели занятия, вопросов, основных понятий и терминов для подготовки к занятию, 20 тестов для проверки уровня знаний по теме, литературы для подготовки и материалов для выполнения практической работы. Итоговые занятия включают цель, вопросы для подготовки, литературу и материалы для выполнения практической работы

Research of the pre-launch powered lubrication device of major parts of the engine D-240

In the publication, the issues have been considered concerning combustion engine start wear of mobile machines in case of outside storage in the conditions of low environmental temperature. Based on the analysis of existing methods and constructions of powered lubrication devices for contact surfaces of engines, a design of a combined device has been suggested which unites the functions of hydraulic and heat accumulators. On the basis of the elaborated design, preparatory tests have been conducted in order to evaluate the effectiveness of pre-start oil circulation in the engine D-240, as well as the effectiveness rate of thermoinsulation and the heating device of the hydraulic accumulator. The findings of the survey have shown that the pre-start powered lubrication device for major parts of the engine is effective

Magnetic Transformations in the Organic Conductor kappa-(BETS)2Mn[N(CN)2]3 at the Metal-Insulator Transition

A complex study of magnetic properties including dc magnetization, 1H NMR and magnetic torque measurements has been performed for the organic conductor kappa-(BETS)2Mn[N(CN)2]3 which undergoes a metal-insulator transition at T_MI~25K. NMR and the magnetization data indicate a transition in the manganese subsystem from paramagnetic to a frozen state at T_MI, which is, however, not a simple Neel type order. Further, a magnetic field induced transition resembling a spin flop has been detected in the torque measurements at temperatures below T_MI. This transition is most likely related to the spins of pi-electrons localized on the organic molecules BETS and coupled with the manganese 3d spins via exchange interaction.Comment: 6 pages, 5 Figures, 1 Table; Submitted to Phys.Rev.B (Nov.2010

Amino Acid Derivatives of Tetrathiafulvalene and Their N-H center dot center dot center dot O Peptide Bond Dipoles-Templated Solid State Assemblies

We report on a series of amino acid derivatives of tetrathiafulvalene as well as on the structure-directing abilities of their peptide residues in the crystalline solid state to stabilize patterns of interactions such as beta strands and sheet motifs. Characteristic hydrogen-bonding motifs are indeed identified within ethylenedithiotetrathiafulvalene (EDT-TTF) and dimethyltetrathiafulvalene (Me-2-TTF) based compounds 1-5. Esters 1-3 contain hydrogen-bond acceptors, namely carbonyl groups, as well as one strong (NH) and one weak (C-sp(2)-H) hydrogen-bond donor. In addition to the hydrogen-bonded sets of ester derivatives, acids 4 and 5 present the carboxylic acid moiety, which acts as both a hydrogen-bond donor and acceptor. EDT-TTF-CO-GlyOH has been previously used to afford a new type of hydrogen-bonded acid/zwitterion (1:1) hybrid admixture of redox peptidics

Functional materials based on TTF amino-acids/peptides

We report the synthesis and crystal chemistry of a series of TTF derivatives bearing simple amino acids such as the achiral Glycine or the chiral Alanine or Valine. The amino acids are linked to the TTF cores via the amino group and the acid functionality is further deprotonated to yield a TTF-carboxylate anion. The latter acts as both a pi-donor and electrolyte in the electrocristallisation experiments which deliver unprecedented zwitterionic (neutral) radicals. Their X-ray structures is analyzed and discussed in relation with their electronic and magnetic properties. This work is further extended to engage simple oligopeptides that can easily be linked to the TTF moiety. The preparation and the X-ray structures of both TTF-peptides and/or their zwitterionic radicals prepared by chemical or electrochemical methods will also be reported with an eye on how self-assembly via peptidic intermolecular interactions may be rationalized to direct the construction of novel pi-functional peptidic architectures

Gearing motion in cogwheel pairs of molecular rotors: weak-coupling limit

Variable-​temp. (VT) crystal structures, VT 1H spin-​lattice relaxation in static crystals, and DFT modeling of the rotational barriers of BCP rotators in cryst. arrays of a rod-​like mol. contg. two 1,​3-​bis(ethynyl)​bicyclo[1.1.1]​pentane (BCP) units demonstrate that a correlated gearing motion occurs in the limit of a weak coupling between two rotors in a pair

When IT Evolves Beyond Community Needs: Coevolution of Bottom-Up IT Innovation and Communities

This paper examines how innovative uses of IT artifacts and their repurposing to fulfill emerging or unsatisfied user needs (bottom-up innovation, BUI) develop in community settings. Based on a longitudinal analysis of “HomeNets,” communities that developed residential internet access in Belarus over a 20-year period, we illustrate that the development of community BUI is driven not only by the needs of the innovating members but also by the interplay between the innovating members’ community context and technology and the interplay between the BUI technology and context. We demonstrate how these dynamics trigger community BUI development that goes beyond the needs and expectations of the innovating actors and impacts community evolution and long-term survival. Based on our findings, we develop a model of community BUI development. We discuss the theoretical implications of our findings, highlighting the role of technology and context in community BUI and its processual unfolding beyond the needs and intentions of the innovating members