CC BY
38
красители; пигменты и прочие красящие вещества; по коду 3208 90 910 1 по ТН ВЭД Республики Узбе-
краски и лаки; шпатлевки и прочие мастики; полигра- кистан. Главная проблема состоит в необходимости
фическая краска, чернила, тушь) в товарной позиции конкретизации субпозиции. 3208 [7]. Исследуемые краски классифицируются
Таблица 1. - Органические соединение в краске 48 L
Время (минут t0 - начальное, ^ - конечное)
t0-2.064-2.137 t,-2.271-2.624 t0-3.939-4.098 t-4.098-4.244 t0 t0-4.244-4.329 t-4.329-4.402 t05.108-5.315 t, 5.450-5.567 t0 5.547-5.632 t, 6.484-6.557
Общее сканирование вещества (раз)
30 15 8 18 8
Структурные формулы
—- "7...... -CK
Название органического вещества
3,5-октадиен 1,3,5-триметил-бензол 1-этил,4-метил бензол диметиловый эфир бутадионовой кислоты п-кумол 1-Метил-4-(1-метилэтил) бензол
Таким образом, на основе газового хроматогра- возможность защитить экономические интересы фа идентифицированы автомобильные краски по ТН и безопасность экономики Узбекистана в междуна-ВЭД Рес.Уз. Разработка новых товарных кодов дает родных отношениях.
Список литературы:
1. Гуревич М. М. Оптические свойства лакокрасочных покрытий [Текст]/М. М. Гуревич, Э. Ф. Ицко, М. М. Середенко; под общ. ред. Э. Ф. Ицко. - Санкт-Петербург: Прфессия, 2010. - С. 11.
2. Яколев А. Д. Химия и технология лакокрасочных покрытий [Текст]: учебник для вузов/А. Д. Яковлев. - 4-е изд., исправл. - Санкт-Петербург: Химиздат, 2010. - С. 7-22.
3. Моисеева Т. Ф. Криминалистическое исследование веществ, материалов и изделий из них [Текст]: курс лекций. - Москва: Изд-во «Щит-М», 2005. - С. 26-28, 102-105, 145-159.
4. Сайты компании «Химмед» - www.chimmed.ruchrom@chimmed.ru.
5. http://www.agilent.com/chem/education.
6. Инструкция и режим работы прибора Agilent 7890B Газовый хроматограф. © Agilent Technologies, Inc. 2013 январь 2013 г.
7. Исломова С. Т., Хамракулов М. Г., Хамракулов Г. Методы испытания, определения толщины сухой плёнки и нанесения лакокрасочного покрытия. Композиционные материалы. Узбекский научно-технический и производственный журнал. № 1/2015. С. 42-45.
Eshmamatova Nodira Baxromovna, National University of Uzbekistan, Seniora Lecturer of the Department of Physical and Colloid Chemistry Akbarov Khamdam Ikromovich, National University of Uzbekistan, Professor of the Department of Physical and Colloid Chemistry
E-mail: Eshmamatova79@mail.ru
Quantitive value of effectivity of nitrogen and phosphor-containing ingibitors by the results electrochemical and gravimetical investigations
Abstract: In article the results of electrochemical and gravimetrical investigation by the influence of new elaborated oligomeric salts on the base of some organic compounds on the corrosion behaviour of steel samples (St -3) in different
Quantitive value of effectivity of nitrogen and phosphor-containing ingibitors by the results electrochemical...
mediums are presented. It was shown that protective effect of investigated oligomeric salts has increased with increasing their molecular mass and hydrocarbon radicals, diminutions presented in the molecules. The influence of the experiments duration and also some other factors on the protective effect of the investigated oligomers have discussed.
Keywords: Oligomers, Inhibitors, steel corrosion, mechanism of inhibition, hydrocarbon, electrochemical investigation.
One of the perspective directions at the elaboration of high- effective regulators of rate of metals electro-precipitation and industrial inhibitors of corrosion is a using of some water- soluble oligomers. The high pollution of environment and hard regimes of exploitation of the technological equipment oil-gaseous branch have caused to great damage from the corrosion which in industrial development contrives has achieved about 10% of the combined profit.
At the exploitation of cooling systems of circulating water-supply in without through high regime the brevity of using of circulating waters has increased what has caused the increasing of their mineralization. Owing to this the investigation of some particularities of the electro-chemical and corrosion behavior of the constructive materials in water with high content of different salts and also the elaboration of different methods of their protection from corrosion is an actual task [1].
Some organic nitrogen — containing compounds are known as effective inhibitors of the acid corrosion of different metals. Aliphatic, aromatically and heterocyclic amides, amines, hinolines and some other compounds are the most investigated in this plan. In spite ofthe wide spectrum of investigations in this field some quash ions have remain practically not enough investigated [2]. Anodic protection by the passivating inhibitors has based on the fact that in process of the reduction the current has appeared which enough to transition metals in passive state. Some salts of Fe 3+ — nitrates, dichromates and some others can be used as inhibitors. Application of such inhibitors has allowed to protect metals in hard accessible places — cracks and clearances; it is necessary to note that their short ate is a contamination of technological medium [3]. Inhibitors can change the rate of corrosion processes if they can to influence on the kinetics of the electrochemical reactions which have caused the corrosion. Car amide (urea) has dissolved in water solution offormaldehyde (phormaline) even at room temperature.
In neutral or weak- based mediums (pH=7...8) and moderate temperatures mono — and di methyl urea were obtained. Di methyl urea is solid colorless substance; it has dissolved in water. At 20-50 o C and molar ratio of urea — formaldehyde 1:1 practically only mono methyl urea was formed. But at molar ratio 1:2 and temperature
above 50 o C some one mole of CH2O has bonded to mono methyl urea with formation of di methyl urea.
Comparison of the rate constants of above mentioned reactions has shown that the reaction ability of NH2 group of mono methyl urea in reaction of condensation in two time less than in urea, but the reaction ability of the methylolic group in di methyl urea in 3 time less than in mono methyl urea. Accordantly condensation in the system urea-formaldehyde has carried out with high rate at their low mole ratio. For example at ratio of initial component 1:1 the rate of reaction is in 3 times higher than at their ratio 2:1. That at higher mole ratios the degree of polycondensation was the same as at low ratios it is necessary to increase the time of reaction and temperature and also to decrease pH of the reaction medium. Thus at pH=4,5 the rates of reactions at the same molar ratios of initial components were the same, but at lower values of pH the rate of condensation was higher and at values of pH above 5.0 on the contrary the rate of addition reaction was higher [4].
Di methyl urea with different acids has formed compounds similar to its phosphate which are soluble in water. Phosphates of di methyl urea in neutral, weak-acid and weak- base mediums at usual temperatures have a linear structure with the degree of polycondensation 8-13; that is they are an oligomers with molecular mass 1418-2400. Investigation of the inhibitoral properties of oligomeric inhibitors on the base of melamine, formalin and phosphoric acid has shown that their protective effect has caused by formation adsorbent layer on the surface of metal. Such inhibitors have bounded with the surface of metal by NH2-groups. By this reason the inhibitoral effect has shown in more degree in compounds having more NH2-groups in their molecules. These groups are the reaction centers' in initial compounds which are used in industrial production of car amide, melamine- formaldehyde oligomers and also linear and linear-cyclical polyamides.
Objects of our investigation were synthesized nitrogen- and phosphor-containing inhibitors: mono phosphate of tio urea (MPTU); mono phosphate of urea (MPU); mono phosphate hexamethylendiamine (MPHMD) and also olig omeric phosphates of di methyl urea (OPDU) and di methyl melamine (OPDM). Inves-
tigation of corrosion behavior of steel (St-3) was carried out on samples in form of plastics on the potenciostat PI-50.11 with programmatic PR-8 by recoding the anodic and cathode polarization curves. The rate of the electrochemical corrosion of metals in acid mediums was determined by measuring of the polarization resistance of two electrode corrosion ditched constant current on the devise R-5035Y.
Investigations were carried out in following phone
+ 5% Na2 CO3 (Ph-2) at different temperatures. Corresponding solutions were prepared from reagents of the mark «chemical pure» on the distilled water. The steel electrodes were obtained from the steel St-3, which has the following composition (%): Fe=98,36; C=0,20; Mn=0,50; Si=0,15; P=0,04; S=0,05; Cr=0,30; Ni=0,20; Cu=0,20. Results of calculation of the corrosion rate and the degree of protection at 50 o C and different concentrations of the investigated inhibitors are presented in table.
solutions: 5% Na2SO4 + 3% H2SO4 (Ph-1), 3% NaCI
Table 1. - Results of the electro-chemical determination of the protective action of Investigated oligomeric inhibitors at their different concentrations in phone solution Ph-1 (pH=5,27)
Inhibitor t, o C mg/l -E, B i, mA/sm 2 g Z,%
Ph-1 0 0,780 536,40 - -
MPTU 0,620 20,54 26,11 96,17
MPU 50 0,560 14,21 37,74 97,35
MPHMD 20 0,590 12,23 43,86 97,72
OPDU 0,430 3,97 135,14 99,26
PDMM 0,450 2,31 232,56 99,57
As shown the best results were obtained in weak-acid medium in the presence of such inhibitors as MPHMD, OPDU and OPDM (20 mg/l). The polarization measuring have shown that nitrogen — and phosphor-containing oligomeric inhibitors OPDU and OPDM in investigated concenrational interval have braked the anodic electrochemical process, that is they are an anodic inhibitors. Inhibitors MPTU, MPU and MPHMD in investigated interval of their concentrations have broken the both electrochemical processes that are they are the in-
hibitors of the mixed type. Mechanism of action of oligomeric inhibitors of corrosion is determined in main by the transition of the surface of protective metal in stable state by formation of film owing to interaction of the inhibitors with metal ions. Analysis of the obtained data had allowed to make conclusion that length of the alkyl radical and molecular mass of the investigated inhibitors have an important influence on their effectively. The protective effect of inhibitors MPU and MPHMD had achieved 97,35-97,72%.
Table 2. - Influence of the duration of the corrosion tests on the effectively of protection of the carbonaceous steel by inhibitor MPU at temperature 25 °C in phone P-1 (pH=5.27)
Cinhibitor [mg/l] 360 hours 720 hours
K [g/(m 2day)] Z [%] K [g/(m 2day) ] Z [%]
0 182,36 — 157,03 —
10 31,58 82,68 26,21 83,31
20 20,57 88,72 14,81 90,57
30 19,82 89,13 14,10 91,02
40 16,65 90,87 13,86 91,17
50 15,24 91,64 13,31 91,52
Table 3. - Influence of the duration of the corrosion tests on the effectively of protection of the carbonaceous steel by inhibitor MPHMD at temperature 25 °C in phone P-1 (pH=8,63)
Cinhibitor [mg/l] 360 hours 720 hours
K [g/(m 2day)] Z [%] K [g/(m 2day) ] Z [%]
0 182,36 — 157,03
10 19,95 89,06 12,62 91,96
20 10,63 94,17 5,487 96,51
30 8,17 95,52 4,98 96,83
40 8,08 95,57 4,69 97,01
50 8,02 95,60 4,79 96,95
Investigation of the mutual effect of the components in systems substantiating the process of obtaining a new defoliant
It is shown from the presented experimental data that tration is 20 mg/l from the economical and techno-the best results were obtained at concentration 50 mg/l logical presentations. These inhibitors by the value of investigated inhibitors MPU and MPHMD. of the protective effect didn't yield to analogues and The obtained results also have shown that at can be used in oil industry for the anticorrosion prosmall concentrations MPU and MPHMD have dis- tection of equipment of boring wells and in some played inhibition properties. Their optimal concen- other fields.
References:
1. Kuznecov V. Y. Physic-chemical aspects of the corrosion inhibition of metals in water solutions//Successes of chemistry. 2004 № 1. T. 73. - P. 79-93.
2. Shpanko S. P., Grigorev V. P., Olexanov E. V., Anisimova V. A. Inhibitional action of benzymidazole derivatives at the acid corrosion of ferrum//Physic-chemistry of surface and the metals protection - M: 2010, T 46, № 2. - P. 208-213.
3. Semenova I. V., Florianovich G. M., Horoshilov A. V. Corrosion and the protection from corrosion - M: 2002. 336 p.
4. Eshmamatova N. B. Protection of carbon steel from corrosion by high-effective oligomeric inhibitors//51-th International Scientific conference MHCK-2013. - Novosibirsk. 2013. - P. 59.
Ergashev Dilmurod Adiljonovich, research assistant of the Institute of General and Inorganic Chemistry the Academy of Sciences of Uzbekistan E- mail: dilmurod-ergashev@rambler.ru Askarova Mamura Komilovna, candidate of chemical sciences (Ph. D. in Chemistry), senior staff scientist of the Institute of General and Inorganic Chemistry the Academy of Sciences of Uzbekistan E-mail: ionxanruz@mail.ru Saiydiaxral Tuxtaev, the head of Defoliant laboratory, doctor of technical sciences, professor, academician, honored inventor and innovator of Uzbekistan, the Institute of General and Inorganic Chemistry the Academy
of Sciences of Uzbekistan E-mail: ionxanruz@mail.ru.
Investigation of the mutual effect of the components in systems substantiating the process of obtaining a new defoliant
Abstract: Heterogenic phase equilibrium in aqueous systems composed of calcium and magnesium chlorates were investigated. It was found that the system including calcium and magnesium chlorates belongs to the simple eutonical type, where salting-out effect of the components to each other were observed. Change dependence of physi-cochemical properties of the solutions in the system, including chlorates and chlorides of calcium and magnesium and carbamide, depending on the composition of components has been studied. "Composition-property" diagram has been constructed for this system.
Keywords: defoliant, polythermal, temperature crystallizations, solubility, diagram, calcium chlorate, magnesium chlorate, carbamide, thermogravimetric, roentgenophasic.
Introduction ment — defoliation by chemical preparations called
In obtaining early and rich crop of raw cotton with defoliants. By chemical effect on cotton plant for the
high technological properties exceptionally an impor- purpose of removal of leaves it is necessary high effective
tant role plays timely conduction of agrotechnical treat- defoliants that can give more than 80% phylloptosis of
