Establishment of foundation nurseries of new grape varieties using method of green grafting in the growing conditions of the Tersko-Kuma sands

Целью работы являлось создание первичных маточников интенсивного типа новых сортов винограда ускоренным методом. В работе представлены результаты закладки первичных маточников методом перепрививки корнесобственных насаждений сорта Цветочный в качестве подвоя на новые селекционные сорта столового назначения Илья, Памяти Смирнова, Барт, ИРС на песчаных землях ОАО «Винхоз «Бурунный», Чеченская республика. Зеленые прививки осуществлялись методом окулировки на зеленый побег с пробуждением глазка на высоте 20-25 см и 40-45 см над уровнем почвы, без пробуждения глазка - на высоте 20-25 см. По результатам данных за 2018 и 2019 гг. сделан вывод о перспективности создания маточников методом зеленой прививки окулировкой. Лучшие данные по приживаемости прививок и их развитию получены в варианте выполнения прививки методом окулировки на высоте 20-25 см с пробуждением глазка, приживаемость прививок в среднем по сортам составила от 74 до 94 %; в варианте с производством окулировки на высоте 40-45 см - 71-88,5%. Метод перепрививки кустов на высоте 20-25 см от поверхности почвы позволил на следующий после прививки год заготовить от 0,86 до 4,2 стандартных черенков нового сорта с одного куста. The aim of the work was to establish intensive type foundation nurseries of new grape varieties by an accelerated method. The paper presents the results of establishing foundation nurseries using sugreffage method of own-rooted plants of the ‘Tsvetochniy’ variety as a rootstock for new breeding table varieties ‘Ilya’, ‘Pamyati Smirnova’, ‘Bart’, ‘IRS’ on sandy lands of OJSC Vinkhoz Burunny of the Chechen Republic. Green grafting was carried out using method of oculation on green shoots with bud awakening at a height of 20-25 cm and 40-45 cm above the soil level, without bud awakening at a height of 20-25 cm. Based on the data results for 2018 and 2019, the prospects of establishing nurseries using method of green grafting were concluded. The best data on grafting survival ability and development was obtained in the variant of oculation with bud awakening at a height of 20-25 cm and ranged from 74% to 94%; in the variant with oculation at a height of 40-45 cm - 71% - 88.5%. The sugreffage method of bushes at a height of 20-25 cm above the soil level allowed harvesting the next year after grafting from 0.86 to 4.2 standard cuttings of new variety per one bush.

Tunable, biodegradable grafting-from glycopolypeptide bottlebrush polymers

The cellular glycocalyx and extracellular matrix are rich in glycoproteins and proteoglycans that play essential physical and biochemical roles in all life. Synthetic mimics of these natural bottlebrush polymers have wide applications in biomedicine, yet preparation has been challenged by their high grafting and glycosylation densities. Using one-pot dual-catalysis polymerization of glycan-bearing α-amino acid N-carboxyanhydrides, we report grafting-from glycopolypeptide brushes. The materials are chemically and conformationally tunable where backbone and sidechain lengths were precisely altered, grafting density modulated up to 100%, and glycan density and identity tuned by monomer feed ratios. The glycobrushes are composed entirely of sugars and amino acids, are non-toxic to cells, and are degradable by natural proteases. Inspired by native lipid-anchored proteoglycans, cholesterol-modified glycobrushes were displayed on the surface of live human cells. Our materials overcome long-standing challenges in glycobrush polymer synthesis and offer new opportunities to examine glycan presentation and multivalency from chemically defined scaffolds.

Adhesion Behavior of Ti–PMMA–Ti Sandwiches for Biomedical Applications

The “stress-shielding” problem, common with metallic implants, may be solved by using biocompatible sandwiches with a polymeric core between two metallic skin sheets. To achieve such sandwiches, a process route has been developed, beginning with the grafting of poly-(methyl-methacrylate) (PMMA) on titanium (Ti) sheets via the “grafting from” technique. Grafting resulted in variable thicknesses of PMMA on the Ti sheets. Hot-pressing was used to prepare semi-finished Ti–PMMA–Ti sandwiches. The adhesion was achieved by the interpenetration between PMMA sheet and the grafted PMMA chains. Investigation was carried out to understand the influence of the grafted PMMA thickness on the adhesion strength. Similar adhesion strengths were found for the sandwiches despite variable grafted PMMA thicknesses, indicating a successful grafting of PMMA on large-scale Ti sheets. The adhesion followed the autohesion theory, where a time-dependent increase in adhesion strength was found for the sandwiches.

Surface Design of Liquid Separation Membrane through Graft Polymerization: A State of the Art Review

Surface modification of membranes is an effective approach for imparting unique characteristics and additional functionalities to the membranes. Chemical grafting is a commonly used membrane modification technique due to its versatility in tailoring and optimizing the membrane surface with desired functionalities. Various types of polymers can be precisely grafted onto the membrane surface and the operating conditions of grafting can be tailored to further fine-tune the membrane surface properties. This review focuses on the recent strategies in improving the surface design of liquid separation membranes through grafting-from technique, also known as graft polymerization, to improve membrane performance in wastewater treatment and desalination applications. An overview on membrane technology processes such as pressure-driven and osmotically driven membrane processes are first briefly presented. Grafting-from surface chemical modification approaches including chemical initiated, plasma initiated and UV initiated approaches are discussed in terms of their features, advantages and limitations. The innovations in membrane surface modification techniques based on grafting-from techniques are comprehensively reviewed followed by some highlights on the current challenges in this field. It is concluded that grafting-from is a versatile and effective technique to introduce various functional groups to enhance the surface properties and separation performances of liquid separation membranes.

Sonochemical Reaction of Bifunctional Molecules on Silicon (111) Hydride Surface

While the sonochemical grafting of molecules on silicon hydride surface to form stable Si–C bond via hydrosilylation has been previously described, the susceptibility towards nucleophilic functional groups during the sonochemical reaction process remains unclear. In this work, a competitive study between a well-established thermal reaction and sonochemical reaction of nucleophilic molecules (cyclopropylamine and 3-Butyn-1-ol) was performed on p-type silicon hydride (111) surfaces. The nature of surface grafting from these reactions was examined through contact angle measurements, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). Cyclopropylamine, being a sensitive radical clock, did not experience any ring-opening events. This suggested that either the Si–H may not have undergone homolysis as reported previously under sonochemical reaction or that the interaction to the surface hydride via a lone-pair electron coordination bond was reversible during the process. On the other hand, silicon back-bond breakage and subsequent surface roughening were observed for 3-Butyn-1-ol at high-temperature grafting (≈150 °C). Interestingly, the sonochemical reaction did not produce appreciable topographical changes to surfaces at the nano scale and the further XPS analysis may suggest Si–C formation. This indicated that while a sonochemical reaction may be indifferent towards nucleophilic groups, the surface was more reactive towards unsaturated carbons. To the best of the author’s knowledge, this is the first attempt at elucidating the underlying reactivity mechanisms of nucleophilic groups and unsaturated carbon bonds during sonochemical reaction of silicon hydride surfaces.

Thiol-Lactam Initiated Radical Polymerization (TLIRP): Scope and Application for the Surface Functionalization of Nanoparticles

: Controlled polymerization techniques make possible fabrication of polymers with desired molecular weights, narrow dispersity, and also tailor-making of advanced hybrid materials. Thiol-Lactam Initiated Radical Polymerization (TLIRP) was introduced in 2002 and developed during the last two decades. The thiol/lactam combination enables one to generate radicals that can initiate the polymerization of vinyl-based monomers. The study of the mechanism and kinetics of TLIRP revealed the characteristics of living polymerization for TLIRP. Moreover, TLIRP has been used successfully for the synthesis of homopolymers, block copolymers, and statistical copolymers with polydispersity below 2.0. Especially, TLIRP provides a very straightforward method for grafting polymer brushes on the surface of nanoparticles. We review herein the systems developed for TLIRP and their applications for macromolecular engineering, with an emphasis on the surface functionalization of nanoparticles via the grafting-from approach.

Novel Amphiphilic Star-Shaped Poly(2-Oxazoline)s with Calix[4]Arene Branching Center

Novel amphiphlic four-arm star-shaped poly (2-alkyl-2-oxazoline) s with calix [4] arene core were synthesized using the “grafting from” approach. The chlorosulfonated calix [4] arene derivative was synthesized and successfully applied as a multifunctional initiator for the cationic ring-opening polymerization of 2-alkyl-2-oxazolines. Obtained star-shaped poly (2-alkyl-2-oxazoline) s were characterized by means of NMR, UV-Vis spectroscopy and gel-permeation chromatography. It was shown that star-shaped poly (2-isopropyl-2-oxazoline) perform thermosensitivity in aqueous solutions.