ПОРІВНЯЛЬНА ХАРАКТЕРИСТИКА ПАТОЛОГІЧНИХ ЗМІН У МІЖХРЕБЦЕВИХ ДИСКАХ ХВОСТОВИХ СЕГМЕНТІВ ЩУРІВ ЗА УМОВ МОДЕЛЮВАННЯ ПОСТІЙНОЇ АСИМЕТРИЧНОЇ КОМПРЕСІЇ-ДИСТЕНЗІЇ ТА ПІСЛЯ КОРЕКЦІЇ ЗБАГАЧЕНОЮ ТРОМБОЦИТАМИ ПЛАЗМОЮ

SUMMARY. In the paper the actual problem of the new method of pathological changes in the intervertebral discs and surrounded tissues at the state of experimental constant asymmetric compression-distension was discussed. As the therapeutic agent the effectiveness of platelet-rich plasma was testifed. It was proved the platelet-rich plasma injection depresses the degenerative-dystrophic process manifestations and improves the affected segment of the spine regeneration. KEY WORDS: intervertebral discs; experimental constant asymmetric compression-distension; correction; platelet-rich plasma.РЕЗЮМЕ. В роботі розглянуто актуальне питання пошуку нового методу корекції патологічних змін міжхребцевих дисків та тканин, що їх оточують, за умов експериментальної постійної асиметричної компресії-дистензії. У якості терапевтичного агенту перевірена ефективність збагаченої тромбоцитами плазми. Доведено, що введення збагаченої тромбоцитами плазми приводить до зменшення проявів дегенеративно-дистрофічного процесу та сприяє відтворенню структури ураженого сегмента хребта. Ключові слова: міжхребцеві диски, експериментальна постійна асиметрична компресія-дистензія, корекція, збагачена тромбоцитами плазма

A functional triazine framework based on N-heterocyclic building blocks

Covalent organic frameworks constitute a subclass of polymeric materials offering enhanced porosity, functionality and stability. In this work a covalent triazine framework based on bipyridine building blocks is presented, along with a comprehensive elucidation of its local structure, porosity, and capacity for metal uptake. A typical synthesis was carried out under ionothermal conditions at 400-700 degrees C using ZnCl2 as a Lewis acidic trimerization catalyst. A high degree of local order and the presence of triazine and bipyridine moieties are ascertained at a synthesis temperature of 400 degrees C, along with micropores and specific surface areas of up to 1100 m(2) g(-1). Mesopores are increasingly formed at synthesis temperatures above 450 degrees C, yielding highly porous frameworks with hierarchical porosity and exceptionally large surface areas in excess of 3200 m(2) g(-1) at 700 degrees C. We demonstrate the capability of the bipyridine unit to provide specific and strong binding sites for a large variety of transition metal ions, including Co, Ni, Pt and Pd. The degree of metal loading (up to 38 wt%) can be tuned by the metal concentration in solution and is dependent on both the type of metal as well as the temperature at which the CTF was synthesized. Evidence for site-specific metal coordination bodes well for the use of metal-loaded CTFs as heterogeneous catalysts carrying homogeneous-type active sites

Polymers of Intrinsic Microporosity derived from a carbocyclic analogue of Tröger's base

Tröger's base (TB) is often used as a building block for the synthesis of Polymers of Intrinsic Microporosity (PIMs) due to its rigid bicyclic V-shaped structure. In this study the TB component in the structure of a PIM is replaced by 2,3:6,7-dibenzobicyclo[3.3.1]nonane, a purely carbocyclic analogue of TB. This modification results in only a slightly reduced amount of microporosity as determined using nitrogen adsorption. Further comparisons with previously reported PIMs indicate that this building unit (and therefore TB) is significantly less effective for the generation of intrinsic microporosity than spirobisindane, a commonly used structural unit for PIM synthesis. It appears that the V-shape of the 2,3:6,7-dibenzobicyclo[3.3.1]nonane and TB units allows closer contact between polymer chains thereby enhancing packing efficiency

Covalently linked organic networks

In this review, we intend to give an overview of the synthesis of well-defined covalently bound organic network materials such as covalent organic frameworks, conjugated microporous frameworks, and other "ideal polymer networks" and discuss the different approaches in their synthesis and their potential applications. In addition we will describe the common computational approaches and highlight recent achievements in the computational study of their structure and properties. For further information, the interested reader is referred to several excellent and more detailed reviews dealing with the synthesis (Dawson et al., 2012; Ding andWang, 2013; Feng et al., 2012) and computational aspects (Han et al., 2009; Colón and Snurr, 2014) of the materials presented here

Dispersible microporous di-block co-polymer Nanoparticles via polymerisation-induced self-assembly

Microporous materials are predominantly formed as insoluble powders which means that they can be difficult to process. Here we report a new class of solvent-dispersible porous polymers synthesised by reversible addition-fragmentation chain transfer mediated polymerisation-induced self-assembly (RAFT-mediated PISA), formed from a PEG macro-CTA polymerised with divinylbenzene and fumaronitrile. The particles have a dual morphology consisting of smaller spheres of 24-29 nm aggregated into larger particles of 204 - 262 nm. Gas sorption analysis showed the particles to have BET surface areas of 274 to 409 m2/g with internal pore sizes centred around 1.8 nm and further larger pores arising from the sphere packing of the aggregates. The particles were found to be photoluminescent (emission λmax = 326 nm) when exposed to UV light which could be quenched by the addition of nitroaromatic compounds. For example, 99% if the emission was quenched in the presence of 38 ppm of picric acid

The Synthesis of Organic Molecules of Intrinsic Microporosity Designed to Frustrate Efficient Molecular Packing

Efficient reactions between fluorine-functionalised biphenyl and terphenyl derivatives with catechol-functionalised terminal groups provide a route to large, discrete organic molecules of intrinsic microporosity (OMIMs) that provide porous solids solely by their inefficient packing. By altering the size and substituent bulk of the terminal groups, a number of soluble compounds with apparent BET surface areas in excess of 600 m2 g−1 are produced. The efficiency of OMIM structural units for generating microporosity is in the order: propellane>triptycene>hexaphenylbenzene>spirobifluorene>naphthyl=phenyl. The introduction of bulky hydrocarbon substituents significantly enhances microporosity by further reducing packing efficiency. These results are consistent with findings from previously reported packing simulation studies. The introduction of methyl groups at the bridgehead position of triptycene units reduces intrinsic microporosity. This is presumably due to their internal position within the OMIM structure so that they occupy space, but unlike peripheral substituents they do not contribute to the generation of free volume by inefficient packing

Covalent and electrostatic incorporation of amines into hypercrosslinked polymers for increased CO2 selectivity

Two methods of incorporating functional groups rich in nitrogen into low cost microporous hypercrosslinked polymers (HCPs) have been evaluated and the effects on the carbon dioxide CO2/N2 IAST selectivity were measured. Electrostatic incorporation of an ammonium salt into a sulfonic acid‐containing HCP polymer afforded a static CO2 uptake of 2.5 mmol g−1 with a CO2/N2 IAST selectivity of 42:1 at 1 bar and 298 K. Using column breakthrough measurements with a 15:85 CO2/N2 mixture at 298 K and 1 bar, a selectivity of 17:1 was obtained. However, varying the counterion resulted in polymers with lower CO2/N2 selectivity values. Decoration of the parent polymer with CO2‐philic imidazole followed by electrostatic ammonium salt incorporation blocked some of the micropores reducing the selectivity which re‐emphasizes the role and importance of pore width for CO2/N2 selectivity

Hyperporous Carbons from Hypercrosslinked Polymers.

Porous carbons with extremely high surface areas are produced through the carbonization of hypercrosslinked benzene, pyrrole, and thiophene. Such carbons show largely microporous and mesoporous domains and exhibit Brunaeur-Emmett-Teller surface areas up to 4300 m(2) g(-1) . The best performing material also displays exceptionally high CO2 and H2 uptakes