The Effectiveness of Compartmentalized Bone Graft Sponges Made Using Complementary Bone Graft Materials and Succinylated Chitosan Hydrogels

Bone defects can occur from many causes, including disease or trauma. Bone graft materials (BGMs) have been used to fill damaged areas for the reconstruction of diseased bone tissues since they are cost effective and readily available. However, BGMs quickly disperse around the tissue area, which ultimately leads to it migrating away from the defect after transplantation. We tested chitosan hydrogels as a useful carrier to hold BGMs in the transplantation area. In this study, we synthesized succinylated chitosan (SCS)-based hydrogels with a high decomposition rate and excellent biocompatibility. We confirmed that BGMs were well distributed inside the SCS hydrogel. The SCS-B hydrogel showed a decrease in mechanical properties, such as compressive strength and Young’s modulus, as the succinylation rate increased. SCS-B hydrogels also exhibited a high cell growth rate and bone differentiation rate. Moreover, the in vivo results showed that the SCS hydrogel resorbed into the surrounding tissues while maintaining the BGMs in the transplantation area for up to 6 weeks. These data support the idea that SCS hydrogel can be useful as a bioactive drug carrier for a broad range of biomedical applications.

Development of technological process of cotton cellulose production and evaluation of experimental results

In the course of this study, the technology of bleaching of cotton pulp for various purposes has been improved, which can be used in the production of cotton pulp by "Khlopoprom-Cellulose" LLP and other enterprises to increase the production efficiency and competitiveness of the products obtained. The proposed development makes it possible to obtain cellulose with a high degree of polymerization and whiteness, as well as to solve the problem of stabilization and high decomposition rate of hydrogen peroxide in the technological cycle. The bleached cellulose meets the requirements of GOST (State Standard) 595-79 "Cotton cellulose" and has an average degree of whiteness of 90%, which is 5-6% higher than the samples of cotton cellulose bleached without the use of a hydrogen peroxide stabilizer.

Detoxification of soil and insurance herbicides in a chernozem typical in the left-bank Forest-Steppe of Ukraine

Goal. The content and detoxification rate of soil (Harnes, k.e.; Stomp 330, k.e.) and post emergent (Callisto 480 SC, KC; Milagro 040 SC, k.c.; Dianat, BRK; Esteron 60, k.e.) herbicides in chernozem typical of permanent corn cultivation technology was studied. Methods. By the method of gas-liquid chromatography, the content of active substances of herbicides in the soil. The mathematical methods established the half-life T50 of active ingredients of the preparations and detoxification rate constants (k) in a chernozem typical were established. Results. The studied herbicides had a rather high decomposition rate in the soil, and on the 45 day the content of their active substances was either not found or was 2.7—9.4% (Harnes, k.e., Dianat, BRK). The shortest half-life of T50 is specific for herbicides with active substances as nicosulfuron (4.6 days) and mesotrione (4.7 days), 2.4-Д 2-ethylhexyl ether (5.3 days) which indicates their low persistence in a chernozem typical and Milagro 040 SC, k.c., Callisto 480 SC, KC, Esteron 60, k.e. characterizes as moderately persistent. For herbicides with the active substance dicamba, pendamethalin and acetochlor, the half-life of T50 was maximum and in the amount to 11.6, 10.2 and 9.9 days, respectively. The biggest half-life of the active substance characterizes as the most stable and dangerous herbicides for the environment. Conclusions. It was confirmed that all the studied herbicides had enough high decomposition rate in the soil in corn agrocenosis. On the 45 day the herbicides Callisto 480 SC, KC, Milagro 040 SC, k.c., Esteron 60, k.e. completely decomposed in the soil, the herbicides Dianat, BRK, Harnes, k.e. — by 91% and 97%, respectively. For the rate constant of the detoxification process (k) in a chernozem typical the herbicides are placed in a row: Dianat, BRK > Stomp 330, k.e. > Harnes, k.e. > Esteron 60, k.e. > Callisto 480 SC, KC > Milagro 040 SC, k.c.

Production of the Hydroxyl Radical and Removal of Formaldehyde by Calcined Green Tuff Powder and Tile

Waste green tuff powder produced by cutting Towada stone has been utilized to eliminate formaldehyde related to greenhouse gases. The green tuff contains TiO2 on zeolite as observed by scanning electron microscope (SEM)t. The green tuff is a natural catalyst that can produce hydrogen peroxide with moisture and oxygen with light. The optimum temperature for calcination of the green tuff powder has been investigated in order to produce hydroxyl radicals from the decomposition of hydrogen peroxide using ultraviolet light (UV) and no light. The green tuff calcined at 800 °C showed a high decomposition rate of hydrogen peroxide with no UV light under high alkaline conditions when measured by using ESR. With UV light, the optimum temperature for calcination of green tuff powder in order to reduce the hydroxyl radical was also 800 °C. Next, the powder calcined at 800 °C was used to produce the tile by compression and heating, and then the formaldehyde adsorption rate was measured. The green tuff powder calcined at 800 °C showed a high adsorption rate, similar to that of the activated carbon. The tiles formed at 40 MPa and heated at 1100 °C were the strongest and also showed adsorption with respect to formaldehyde. The adsorbed formaldehyde on the green tuff tile and powder was possibility decomposed by the hydroxyl radical produced by photocatalysis.

Preparation and Structure of W/Mo Films and Their Tribological Properties in the Lubrication of MoDTC

W, Mo, and W–Mo alloy films are prepared on 316L stainless steel by means of ion beam assisted deposition (IBAD). Tribological behaviors of the treated surfaces are investigated under lubrication with molybdenum dialkyldithiocarbamate (MoDTC) on a MS-T3000 friction and wear tester. The micromorphologies and chemical characteristics of the tribofilms generated on the worn surfaces are analyzed by scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS), respectively. The results showed that the obvious synergistic effects of better friction reduction and wear resistance between W–Mo film and MoDTC are attributed to the hard surface and the high decomposition rate of additives on the worn W–Mo surface.

Barrier and Copper Seedlayer Wet Etching

This paper summarizes the process development of TiN barrier etching in presence of copper, for a thick copper level in BICMOS technology. In an industrial context, we have chosen to use a SC1 chemistry in a spin etch single wafer tool. The SC1 composition and therefore the pH level allows - the barrier to be etched with no metallic residues, ( if not clear this can be a source for shorts) - control of the selectivity between copper and TiN - control of lateral etching under copper lines, the possible source of open chains by W attack during TiN etch. The electrical results show a robust process according to current specifications, in terms of leakage and via resistance with a fresh chemistry approach. In fact, the recirculation of SC1 is not possible due to substantial concentration changes during processing, high evaporation rate of Ammonia and high decomposition rate of Peroxide in the presence of copper on surface wafer.