Darbo objektai: Virtų, karštai rūkytų dešrų gamyba, juslinių savybių ir mikrobiologinis dešrų įvertinimas. Darbo tikslas – Įvertinti natrio druskų mažinimo galimybes termiškai apdorotuose mėsos gaminiuose. Darbo užduotys: 1. Mokslinės literatūros apie natrio druskų mažinimo galimybes termiškai apdorotuose mėsos gaminiuose apibendrinimas. 2. Natrio druskų pakeitimo alternatyviais ingredientais virtose ir karštai rūkytose dešrose galimybių tyrimas. 3. Gaminių receptūrų sudarymas, gaminių gamyba, juslinis įvertinimas. 4. Gautų rezultatų statistinis apdorojimas, apibendrinimas, išvadų formulavimas. Darbo rengimo vieta: Tiriamasis darbas buvo atliktas Lietuvos sveikatos mokslų universitete Veterinarijos akademijoje Maisto saugos ir kokybės katedroje ir „X“ mėsos perdirbimo įmonėje. Tyrimai buvo atlikti Šiaulių Nacionalinio maisto ir veterinarijos rizikos vertinimo institute. Darbo apimtis: 46 puslapiai, 11 lentelės, 10 paveikslų, 4 priedai Raktažodžiai: virta dešra, karštai rūkyta dešra, natrio druska Išvados: 1. 50 proc. nitritinės druskos kiekio pakeitimas kalcio laktatu virtose dešrose ženkliai padidino aerobinių mikroorganizmų skaičių, todėl toks pakeitimas nėra tinkamas taikyti virtų dešrų gamyboje. Kiti tyrime tirti natrio nitrito pakaitalai virtose ir karštai rūkytose dešrose nežymiai padidino aerobinių mikroorganizmų skaičių; 2. Nitritinės druskos pakeitimas 50 proc. kalio chloridu ir 50 proc. kalcio laktatu turėjo nežymią įtaką virtų dešrų juslinėms savybėms bei... [toliau žr. visą tekstą] / Objects of the thesis: Production of cooked, smoked sausages, evaluation of sausages of organoleptic characteristics and microbiological. Aim of the thesis is to rate the possibilities of sodium salt reduction in the heat-treated meat products. Purpose of the thesis: 1. Summary of the scientific literature on possibilities of sodium salt reduction in the heat-treated meat products. 2. Research of possibilities of the change of the sodium salt by the alternative ingredients in the cooked and smoked sausages. 3. Formation of the products recipes, manufacture of the products and sensory evaluation. 4. Statistical processing of the obtained results, generalization, and formulation of conclusions. Work preparation place ant term: The research was performed at the Food Safety and Quality Department of the Veterinary Academy of the Lithuanian University of Health Sciences and at the company of meat processing “X”. The research was performed at the Šiauliai National Food and Veterinary Risk Assessment Institute. Work span: The thesis consists of: 46 pages, 11 tables, 10 pictures, 4 annexes Keywords: cooked sausage, smoked sausage, sodium salt Conclusions: 1. 50% nitric salt replacement to calcium lactate leads to increase of aerobic microorganisms in cooked sausages and it is therefore unsuitable for the production of cooked sausages. The other investigated nitric salt replacement variants do not show a significant increase of aerobic microorganisms in cooked and smoked... [to full text]

In the past three decades, a new group of concrete admixtures, termed &ldquo / superplasticizers&rdquo / , were introduced to the concrete industry. They have gained wide acceptance because of their many advantages. The addition of superplasticizers to concrete improves the workability and strength of concrete. In this study, the effect of the chemical structure of poly (4-styrenesulfonic acid-co-maleic acid) sodium salt (SSAMA), which contains both sulfonic and carboxylic acid groups, which is a new superplasticizer, was analyzed. Two different molecular weights of PEG (polyethylene glycol monomethyl ether) were grafted to this water-soluble copolymer at different weight compositions. The structures of synthesized copolymers were verified by FTIR and NMR analyses. The molecular weight difference of the grafted copolymers with different side chain lengths was determined by dilute solution viscosimetry. The effects of chemical structure of grafted copolymers on the fluidity of cement paste and the mechanical properties of the mortars were investigated. The zeta potential measurements revealed the interactions between the cement particles and polycarboxylate type superplasticizers. The maximum fluidity was achieved for the PEG grafted copolymer with the weight ratio 3:3. The mechanical properties of this copolymer showed the highest flexural and compressive strength compared to other copolymers. The addition of various Li salts to SSAMA affected the ionic medium, therefore, the dispersion performance of cement paste and the mechanical properties of the mortars improved. The mixture of LiCl: SSAMA in 1:1 mol ratio exhibited the maximum fluidity compared to other Li salts and their compositions. This mixture gave the highest flexural strength but the mixture of Li2CO3 in 1:1 composition gave the highest compressive strength in each salt mixtures.

This thesis deals with the liquid aprotic electrolytes with solvent on the basis of sulfolane blends with other solvent, in combination with the sodium and lithium salts. In these electrolytes are evaluated their properties due to their use in lithium - ion batteries in terms of safety and electrical properties. For safety risk is measured flashpoint and for electrical properties is measured electrical conductivity for selected samples are intended capacities of double layers.

Establishing highly sophisticated polymer films for delivery systems in a biological environment and bioanalytical tasks, the formation, thickness, swelling behavior, and (physiological) stability of highly biocompatible polyelectrolyte multilayers (PEMs) are described. These PEMs are composed of the very weak polycation maltose-modified hyperbranched poly(ethyleneimine) (PEI-Mal), strongly polyanion heparin sodium salt (HE − Na +) or weakly charged polyanion hyaluronic acid sodium salt (HA-Na+) deposited on Si wafer substrates. Two different glyco architectures for PEI-Mal are used, characterized by two different degrees of maltose decoration on a PEI scaffold. Using three pH-dependent deposition approaches for optimizing the (physiological) PEM stability and swelling, PEMs are characterized by (in situ) ellipsometry, atomic force microscopy (AFM), and (in situ) attenuated total reflection-Fouriertransform infrared (ATR-FTIR). Thus, PEMs reveal significantly different thicknesses, growth mechanisms (linear versus exponential), and swelling behavior in dependence of both the polycation architectures and the deposition protocol. These PEMs will allow the study of their complexation and release properties as preswollen PEMs against anionic drug molecules, adenosine triphosphate sodium salt (ATP), especially under physiological conditions for future drug delivery coatings.

Establishing highly sophisticated polymer films for delivery systems in a biological environment and bioanalytical tasks, the formation, thickness, swelling behavior, and (physiological) stability of highly biocompatible polyelectrolyte multilayers (PEMs) are described. These PEMs are composed of the very weak polycation maltose-modified hyperbranched poly(ethyleneimine) (PEI-Mal), strongly polyanion heparin sodium salt (HE − Na +) or weakly charged polyanion hyaluronic acid sodium salt (HA-Na+) deposited on Si wafer substrates. Two different glyco architectures for PEI-Mal are used, characterized by two different degrees of maltose decoration on a PEI scaffold. Using three pH-dependent deposition approaches for optimizing the (physiological) PEM stability and swelling, PEMs are characterized by (in situ) ellipsometry, atomic force microscopy (AFM), and (in situ) attenuated total reflection-Fouriertransform infrared (ATR-FTIR). Thus, PEMs reveal significantly different thicknesses, growth mechanisms (linear versus exponential), and swelling behavior in dependence of both the polycation architectures and the deposition protocol. These PEMs will allow the study of their complexation and release properties as preswollen PEMs against anionic drug molecules, adenosine triphosphate sodium salt (ATP), especially under physiological conditions for future drug delivery coatings.

Объектом исследования являлось вещество натриевая соль 2-этилтио-6-нитро-1,2,4-триазоло-[5,1-c]-1,2,4-триазин-7-она, дигидрат (УПИ-802). Цель работы: количественное определение лекарственного вещества натриевой соли 2-этилтио-6-нитро-1,2,4-триазоло-[5,1-c]-1,2,4-триазин-7-она дигидрата методом вольтамперометрии. В случае УПИ-802 наиболее полезным для количественного определения является сигнал электровосстановления нитрогруппы. Исследованы процессы восстановления нитрогруппы исследуемого вещества в водных и апротонных растворах с применением вольтамперометрии в условиях физического удаления растворенного кислорода и без удаления кислорода. Установлено, что скорость восстановления УПИ-802 контролируется диффузией, процесс восстановления нитрогруппы является необратимым и проходит в две стадии в буферном растворе Бриттона-Робинсона. Первая волна восстановления, которая лежит в области потенциалов -0,31 – (-0,8) В, соответствует присоединению 4 электронов. Обнаружено, что электровосстановление нитрогруппы протекает с предшествующим протонированием. Выбран оптимальный режим регистрации аналитического сигнала исследуемого вещества УПИ-802 на стеклоуглеродном электроде в условиях химического способа удаления растворенного кислорода – квадратно-волновой с амплитудой импульса 0,05 В, частотой импульса 35 Гц. Показана возможность применения толстопленочных углеродсодержащих электродов для определения исследуемого вещества методом квадратно-волновой вольтамперометрии. Выполнена оценка показателей качества методики анализа, таких как линейность, повторяемость (сходимость) и внутрилабораторная прецизионность. / The object of the study was the substance 2-ethylthio-6-nitro-1,2,4-triazolo-[5,1-c]-1,2,4-triazin-7-one sodium salt dihydrate (UPI-802). Objective: quantification of 2-ethylthio-6-nitro-1,2,4-triazolo-[5,1-c]-1,2,4-triazin-7-one sodium salt dihydrate by the method of voltammetry. For UPI-802, the signal of electroreduction of a nitro group is the most useful for quantitative determination. The processes of the nitro group reduction of the test substance in aqueous and aprotic solutions was studied using voltammetry in conditions of physical removal of dissolved oxygen and without oxygen removal. It was established that the rate of reduction of UPI-802 is controlled by diffusion, the processes of reduction of the nitro group is irreversible and proceeds in two stages in a Britton-Robinson buffer solution. The first recovery wave, lying in the potential region of -0,31 - (-0,8) V, corresponds to the addition of 4 electrons. It was found that the electroreduction of the nitro group proceeds with previous protonation. The optimal mode for recording the analytical signal of the UPI-802 on the glassy carbon electrode was selected in conditions of chemical method for removing dissolved oxygen – square-wave with a pulse amplitude of 0,05 V and a pulse frequency of 35 Hz. The possibility of using thick-film carbon-containing electrodes to determine the test substance by the method of square-wave voltammetry was shown. The quality indicators of the analysis technique, such as linearity, repeatability (convergence) and intralaboratory precision, were evaluated.