Pub Date : 2017-08-22DOI: 10.5755/j01.ct.68.1.18877
E. Urbonavičiūtė, R. Vaickelionienė, G. Vaickelionis, V. Mickevičius
Susintetinta eilė funkcionalizuotą tiazolo žiedą turincių N,N -dipakeistųjų β-aminorūgscių. Antibakterinis gautų junginių poveikis Xanthomonas campestris , Rhizobium radiobacter ir Escherichia coli bakterijų padermėms istirtas difuzijos į agarą metodu. Tyrimais nustatyta, kad tiazolono ir 4-chlorbenzaldehido kondensacijos produktas ( Z )-3-[(5-(4-chlorbenziliden)-4-okso-4,5-dihidrotiazol-2-il)(4-metoksifenil)amino]propano rūgstis slopina bakterijų Xanthomonas campestris ir Rhizobium radiobacter augimą. DOI: http://dx.doi.org/10.5755/j01.ct.68.1.18877
{"title":"SYNTHESIS AND ANTIBACTERIAL PROPERTIES OF N,N-DISUBSTITUTED β-AMINO ACIDS CONTAINING FUNCTIONALIZED THIAZOLE FRAGMENT IN THE STRUCTURE","authors":"E. Urbonavičiūtė, R. Vaickelionienė, G. Vaickelionis, V. Mickevičius","doi":"10.5755/j01.ct.68.1.18877","DOIUrl":"https://doi.org/10.5755/j01.ct.68.1.18877","url":null,"abstract":"Susintetinta eilė funkcionalizuotą tiazolo žiedą turincių N,N -dipakeistųjų β-aminorūgscių. Antibakterinis gautų junginių poveikis Xanthomonas campestris , Rhizobium radiobacter ir Escherichia coli bakterijų padermėms istirtas difuzijos į agarą metodu. Tyrimais nustatyta, kad tiazolono ir 4-chlorbenzaldehido kondensacijos produktas ( Z )-3-[(5-(4-chlorbenziliden)-4-okso-4,5-dihidrotiazol-2-il)(4-metoksifenil)amino]propano rūgstis slopina bakterijų Xanthomonas campestris ir Rhizobium radiobacter augimą. DOI: http://dx.doi.org/10.5755/j01.ct.68.1.18877","PeriodicalId":22505,"journal":{"name":"the Chemical Technology","volume":"29 1","pages":"55-62"},"PeriodicalIF":0.0,"publicationDate":"2017-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74914839","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-08-22DOI: 10.5755/j01.ct.68.1.18875
V. Vaitkevičienė, A. Narkuniene
Designing a repository for radioactive waste as a multi-barrier system with predefined multiple safety functions provides for the protection of people and environment from the harmful effect of the ionising radiation of radionuclides once released from high-level radioactive waste. The multi-barrier system is comprised of the engineered barrier system (EBS) and its surrounding natural environment. Because of the high retention capacity for the radionuclides, various forms of bentonite are usually considered as a part of the EBS in the design of radioactive waste repositories. Laboratory batch experiments with natural sediments illustrate that the sorption (and K d values) is sensitive to aqueous chemical conditions, including the pH and the dissolved carbonate concentration as well as the mineralogy and surface area of the bentonite buffer. The cations considered for the study were chosen as covering a representative range of cations behaviour: from a weakly sorbed cation Cs(I) to moderately sorbed cation the Ni(II) and strongly sorbed cation, Eu(III). In this study, a potential retardation of sorbing radionuclides (Cs, Ni, Eu) as a function of aqueous chemical conditions in the groundwater of the Lithuanian crystalline basement contacting the bentonite material was estimated for the first time. The ion exchange and surface complexation models (SPNE/CE) and the computer program PHREEQC (USA) were applied for modelling the interaction within the radionuclide/water/bentonite system. The modelling of the K d values under different pH conditions and a given partial pressure of carbon dioxide in the gas phase were performed. The highest value of K d in the pCO 2 open system and the strongest sorption dependence on pCO 2 was estimated for Eu(I) among radionuclides being studied. There was estimated only a slight change in K d values with respect to the temperature. DOI: http://dx.doi.org/10.5755/j01.ct.68.1.18875
{"title":"APPLICATION OF SURFACE COMPLEXATION AND ION EXCHANGE MODELLING FOR THE ESTIMATION OF BENTONITE SORPTION CAPACITY ON SELECTED RADIONUCLIDES UNDER POSSIBLE GEOLOGICAL DISPOSAL CONDITIONS IN LITHUANIA","authors":"V. Vaitkevičienė, A. Narkuniene","doi":"10.5755/j01.ct.68.1.18875","DOIUrl":"https://doi.org/10.5755/j01.ct.68.1.18875","url":null,"abstract":"Designing a repository for radioactive waste as a multi-barrier system with predefined multiple safety functions provides for the protection of people and environment from the harmful effect of the ionising radiation of radionuclides once released from high-level radioactive waste. The multi-barrier system is comprised of the engineered barrier system (EBS) and its surrounding natural environment. Because of the high retention capacity for the radionuclides, various forms of bentonite are usually considered as a part of the EBS in the design of radioactive waste repositories. Laboratory batch experiments with natural sediments illustrate that the sorption (and K d values) is sensitive to aqueous chemical conditions, including the pH and the dissolved carbonate concentration as well as the mineralogy and surface area of the bentonite buffer. The cations considered for the study were chosen as covering a representative range of cations behaviour: from a weakly sorbed cation Cs(I) to moderately sorbed cation the Ni(II) and strongly sorbed cation, Eu(III). In this study, a potential retardation of sorbing radionuclides (Cs, Ni, Eu) as a function of aqueous chemical conditions in the groundwater of the Lithuanian crystalline basement contacting the bentonite material was estimated for the first time. The ion exchange and surface complexation models (SPNE/CE) and the computer program PHREEQC (USA) were applied for modelling the interaction within the radionuclide/water/bentonite system. The modelling of the K d values under different pH conditions and a given partial pressure of carbon dioxide in the gas phase were performed. The highest value of K d in the pCO 2 open system and the strongest sorption dependence on pCO 2 was estimated for Eu(I) among radionuclides being studied. There was estimated only a slight change in K d values with respect to the temperature. DOI: http://dx.doi.org/10.5755/j01.ct.68.1.18875","PeriodicalId":22505,"journal":{"name":"the Chemical Technology","volume":"12 1","pages":"36-46"},"PeriodicalIF":0.0,"publicationDate":"2017-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78942610","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-08-22DOI: 10.5755/j01.ct.68.1.18879
V. Vītola, B. Ozola
A lot of ingredients used for food may have their own antioxidant activity. For this reason, it is necessary to explore the effect of natural antioxidants and non-specific antioxidants of some confectionery ingredients for the stabilization of food products against the formation of peroxides. The aim of the study was to verify the effect of some carbohydrates in preventing the formation of peroxides in fat for the confectionery production and to prove that the quality and shelf-life of confectionery products are affected by ingredients used in the compositions of confectionery products and by compounds that are formed in their interaction. Butter was used as the basic ingredient to study the fat stability. The effect of carbohydrates used in confectionery and their interaction with butter was examined, and the peroxides were determined. The effect of vanillin in facilitating or preventing the above-mentioned interaction was also determined. Peroxides were determined by means of the standard LVS EN ISO 3960:2010. It was established that practically all carbohydrates decreased the formation of peroxides in the samples. The quantity of peroxides in butter with 30 % of sucrose was by 10.7 % lower, with 30 % of glucose – by 41.3 % lower comparing to butter without additives after the samples had been stored for 30 days at 28 ± 2 °C. The most effective after 30 days of storage was sorbitol which decreased the formation of peroxides by 65.3 %. The same activity was also established for vanillin. Its antioxidant activity was similar to the activity of sugars, and therefore their summary activity reduces in confectionery products. It is established that the activity of sugars is quite temporary, and with increasing the quantity of peroxides in the product it decreases or completely disappears. DOI: http://dx.doi.org/10.5755/j01.ct.68.1.18879
许多用于食品的成分可能具有自身的抗氧化活性。因此，有必要探索一些糖果成分的天然抗氧化剂和非特异性抗氧化剂对食品稳定的作用，以防止过氧化物的形成。这项研究的目的是验证一些碳水化合物在防止糖果生产中脂肪中过氧化物形成方面的作用，并证明糖果产品的质量和保质期受到糖果产品成分中使用的成分以及它们相互作用中形成的化合物的影响。以黄油为基本原料，研究其脂肪稳定性。考察了糖类在糖果中的作用及其与黄油的相互作用，并测定了过氧化物的含量。还测定了香兰素促进或阻止上述相互作用的作用。过氧化物的测定方法为LVS EN ISO 3960:2010。结果表明，几乎所有的碳水化合物都能减少样品中过氧化物的形成。在28±2°C下保存30天后，与不添加添加剂的黄油相比，添加30%蔗糖的黄油中过氧化物的数量减少了10.7%，添加30%葡萄糖的黄油中过氧化物的数量减少了41.3%。贮藏30天后，山梨醇的效果最好，可使过氧化物的形成减少65.3%。对香兰素也有相同的活性。它的抗氧化活性与糖的活性相似，因此它们在糖果产品中的总活性降低。可以确定的是，糖的活性是相当暂时的，并且随着产品中过氧化物数量的增加，它会减少或完全消失。DOI: http://dx.doi.org/10.5755/j01.ct.68.1.18879
{"title":"EFFECT OF VARIOUS CARBOHYDRATE ADDITIVES ON PEROXIDE FORMATION IN FAT FOR CONFECTIONERY PRODUCTION","authors":"V. Vītola, B. Ozola","doi":"10.5755/j01.ct.68.1.18879","DOIUrl":"https://doi.org/10.5755/j01.ct.68.1.18879","url":null,"abstract":"A lot of ingredients used for food may have their own antioxidant activity. For this reason, it is necessary to explore the effect of natural antioxidants and non-specific antioxidants of some confectionery ingredients for the stabilization of food products against the formation of peroxides. The aim of the study was to verify the effect of some carbohydrates in preventing the formation of peroxides in fat for the confectionery production and to prove that the quality and shelf-life of confectionery products are affected by ingredients used in the compositions of confectionery products and by compounds that are formed in their interaction. Butter was used as the basic ingredient to study the fat stability. The effect of carbohydrates used in confectionery and their interaction with butter was examined, and the peroxides were determined. The effect of vanillin in facilitating or preventing the above-mentioned interaction was also determined. Peroxides were determined by means of the standard LVS EN ISO 3960:2010. It was established that practically all carbohydrates decreased the formation of peroxides in the samples. The quantity of peroxides in butter with 30 % of sucrose was by 10.7 % lower, with 30 % of glucose – by 41.3 % lower comparing to butter without additives after the samples had been stored for 30 days at 28 ± 2 °C. The most effective after 30 days of storage was sorbitol which decreased the formation of peroxides by 65.3 %. The same activity was also established for vanillin. Its antioxidant activity was similar to the activity of sugars, and therefore their summary activity reduces in confectionery products. It is established that the activity of sugars is quite temporary, and with increasing the quantity of peroxides in the product it decreases or completely disappears. DOI: http://dx.doi.org/10.5755/j01.ct.68.1.18879","PeriodicalId":22505,"journal":{"name":"the Chemical Technology","volume":"2016 1","pages":"68-73"},"PeriodicalIF":0.0,"publicationDate":"2017-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87786347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-08-22DOI: 10.5755/J01.CT.68.1.15006
C. Stone, R. Dráb, F. Vranay
Engineers, architects and designers increasingly rely on mathematical constructs incorporated into civil engineering programs to explain physical and mechanical phenomena. A low thermal diffusivity represents a material’s ability to slow down the rate of heat transfer due to heat absorption and storage, so that high thermal masses are desirable. The thermal inertia of the earth structures in general is an under-researched topic, especially regarding their unique ability to delay and attenuate temperature responses. The paper uses a high temperature difference example, in the form of an experimental stove, to highlight the benefits of a thermal mass. Countries such as Austria, the Czech Republic and Slovakia are known for their ornate historical masonry stoves that grace many stately houses, castles and palaces. They were stoked once or twice daily and radiated heat constantly during the winter months. This guild developed and thrived until the advent of modern HVAC systems in the 20th century. The paper sets out to monitor the temperature difference produced by stoking and firing a simplified experimental stove and analyses the decrease in temperature until it approaches a fixed room temperature. Temperature and heat flux are then observed to determine the total residual heat energy after burning, and the results are discussed in the conclusion. Inspired by these sound principles, based on lessons from the vernacular building traditions that have been used for centuries, the output of this work could be used in future to design an appropriate amount of the thermal mass to maximize thermal efficiency in fireplaces and stoves and as a precedent for a synergetic combination of the thermal mass and renewable energy sources.DOI: http://dx.doi.org/10.5755/j01.ct.68.1.15006
{"title":"ACCUMULATION OF RESIDUAL ENERGY OF AN EXPERIMENTAL STOVE AFTER BURNING","authors":"C. Stone, R. Dráb, F. Vranay","doi":"10.5755/J01.CT.68.1.15006","DOIUrl":"https://doi.org/10.5755/J01.CT.68.1.15006","url":null,"abstract":"Engineers, architects and designers increasingly rely on mathematical constructs incorporated into civil engineering programs to explain physical and mechanical phenomena. A low thermal diffusivity represents a material’s ability to slow down the rate of heat transfer due to heat absorption and storage, so that high thermal masses are desirable. The thermal inertia of the earth structures in general is an under-researched topic, especially regarding their unique ability to delay and attenuate temperature responses. The paper uses a high temperature difference example, in the form of an experimental stove, to highlight the benefits of a thermal mass. Countries such as Austria, the Czech Republic and Slovakia are known for their ornate historical masonry stoves that grace many stately houses, castles and palaces. They were stoked once or twice daily and radiated heat constantly during the winter months. This guild developed and thrived until the advent of modern HVAC systems in the 20th century. The paper sets out to monitor the temperature difference produced by stoking and firing a simplified experimental stove and analyses the decrease in temperature until it approaches a fixed room temperature. Temperature and heat flux are then observed to determine the total residual heat energy after burning, and the results are discussed in the conclusion. Inspired by these sound principles, based on lessons from the vernacular building traditions that have been used for centuries, the output of this work could be used in future to design an appropriate amount of the thermal mass to maximize thermal efficiency in fireplaces and stoves and as a precedent for a synergetic combination of the thermal mass and renewable energy sources.DOI: http://dx.doi.org/10.5755/j01.ct.68.1.15006","PeriodicalId":22505,"journal":{"name":"the Chemical Technology","volume":"23 1","pages":"12-17"},"PeriodicalIF":0.0,"publicationDate":"2017-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73618090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-08-22DOI: 10.5755/j01.ct.68.1.18872
L. Šāble, K. Kalniņš
Glass as a structural material has strongly evolved in modern architecture. Wide windows, glass facades and even load-bearing structures make buildings appear transparent and more integrated in the surrounding environment. According to the ongoing effort by the European Committee for Electrotechnical Standardisation, only recently the notice “ Eurocode on glass in construction ” has been issued. This will make applicable the binding design practice in the EU starting from the next decade. This design practice will include, among others, the required properties of material and products, application fields, respective failure potential and failure consequences, safety and reliability approaches, principles of design, design and calculation rules for primary members, joints, connections and supports. This standard will be binding in all European countries, therefore, until then every member state should adapt these guidelines in order to make safe design practices for glass structures. At present, in Latvia there is no enforced regulation for glass-bearing structural design and a scattered view on the mechanical properties of the available glass applied for load-carrying designs. In the present verification study, laboratory testings were performed to characterise glass mechanical properties such as stiffness and bending strength of the set of specimens provided by national distributers. For this reason, a series of samples has been tested by a 4-point bending with two different geometrical settings 360 ´ 1100 mm (EN 1228-3) and short beam tests of 50 ´ 200 mm. The current research has shown that compared with the Eurocode reference values, these test results show a lower strength of the internally available raw glass panels. The cause should be merged with edge grinding technology and studied in more detail in the further analysis. DOI: http://dx.doi.org/10.5755/j01.ct.68.1.18872
玻璃作为一种结构材料在现代建筑中得到了强有力的发展。宽大的窗户，玻璃幕墙，甚至承重结构，使建筑显得透明，更融入周围环境。根据欧洲电工标准化委员会的持续努力，直到最近才发布了“欧洲建筑玻璃规范”的通知。这将使绑定设计实践从下一个十年开始在欧盟适用。该设计实践将包括材料和产品所需的特性、应用领域、各自的失效可能性和失效后果、安全和可靠性方法、设计原则、主要构件、接头、连接和支撑的设计和计算规则等。该标准将在所有欧洲国家具有约束力，因此，在此之前，每个成员国都应该适应这些指导方针，以使玻璃结构的安全设计实践。目前，在拉脱维亚，对玻璃承重结构设计没有强制规定，对用于承载设计的可用玻璃的机械性能的看法也很分散。在目前的验证研究中，进行了实验室测试，以确定国家分销商提供的一套样品的玻璃机械特性，如刚度和弯曲强度。为此，一系列样品通过两种不同几何设置360´1100 mm (EN 1228-3)的4点弯曲和50´200 mm的短梁测试进行了测试。目前的研究表明，与欧洲规范的参考值相比，这些测试结果显示内部可用的原玻璃板的强度较低。其原因应与磨边技术相结合，在进一步的分析中进行更详细的研究。DOI: http://dx.doi.org/10.5755/j01.ct.68.1.18872
{"title":"VERIFICATION OF AVAILABLE GLASS MECHANICAL PROPERTIES AGAINST RECOMMENDATION BY THE DRAFT EUROCODE DESIGN PRACTICE","authors":"L. Šāble, K. Kalniņš","doi":"10.5755/j01.ct.68.1.18872","DOIUrl":"https://doi.org/10.5755/j01.ct.68.1.18872","url":null,"abstract":"Glass as a structural material has strongly evolved in modern architecture. Wide windows, glass facades and even load-bearing structures make buildings appear transparent and more integrated in the surrounding environment. According to the ongoing effort by the European Committee for Electrotechnical Standardisation, only recently the notice “ Eurocode on glass in construction ” has been issued. This will make applicable the binding design practice in the EU starting from the next decade. This design practice will include, among others, the required properties of material and products, application fields, respective failure potential and failure consequences, safety and reliability approaches, principles of design, design and calculation rules for primary members, joints, connections and supports. This standard will be binding in all European countries, therefore, until then every member state should adapt these guidelines in order to make safe design practices for glass structures. At present, in Latvia there is no enforced regulation for glass-bearing structural design and a scattered view on the mechanical properties of the available glass applied for load-carrying designs. In the present verification study, laboratory testings were performed to characterise glass mechanical properties such as stiffness and bending strength of the set of specimens provided by national distributers. For this reason, a series of samples has been tested by a 4-point bending with two different geometrical settings 360 ´ 1100 mm (EN 1228-3) and short beam tests of 50 ´ 200 mm. The current research has shown that compared with the Eurocode reference values, these test results show a lower strength of the internally available raw glass panels. The cause should be merged with edge grinding technology and studied in more detail in the further analysis. DOI: http://dx.doi.org/10.5755/j01.ct.68.1.18872","PeriodicalId":22505,"journal":{"name":"the Chemical Technology","volume":"81 1","pages":"5-11"},"PeriodicalIF":0.0,"publicationDate":"2017-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77657150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-08-22DOI: 10.5755/J01.CT.68.1.18874
K. Jančaitienė, R. Šlinkšienė
In the production of many products in various industries, especially chemical, the positive aspect is the creation and use of a waste-free technology. It has been found that the content of a liquid phase after interaction between NH 4 H 2 PO 4 and KCl (the molar ratio of the starting materials was 0.8 : 0.2) depends on the conversion temperatures. The chemical composition of the liquid phase can vary from 1.19 to 1.45 % of N, from 14.96 to 26.55 % of K 2 O, from 1.06 to 2.55 % of P 2 O 5 and from 13.42 to 13.71 % of Cl. The other properties of the solutions, such as pH , density and viscosity, are almost independent of temperature and meet the requirements for liquid compound fertilizers. This means that it is possible to produce a liquid fertilizer 4–5–15 grade in the post-crystallization of potassium dihydrogen phosphate remaining solution (when the molar ratio of the starting materials is 0.8 : 0.2) by adding 6 % of CO(NH 2 ) 2 wherein the crystallization temperature is 15 °C. It has been discovered that the liquid fertilizers 4–5–15 grade are efficient and give a bigger yield of plants. It increased the test plate dry weight by 78.2 %, the ash content by 41.6 % and the height of the plants by 31.2 %. DOI: http://dx.doi.org/10.5755/j01.ct.68.1.18874
{"title":"MANUFACTURING OF LIQUID COMPOUND FERTILIZERS FROM WASTE POTASSIUM DIHYDROGEN PHOSPHATE PRODUCTION","authors":"K. Jančaitienė, R. Šlinkšienė","doi":"10.5755/J01.CT.68.1.18874","DOIUrl":"https://doi.org/10.5755/J01.CT.68.1.18874","url":null,"abstract":"In the production of many products in various industries, especially chemical, the positive aspect is the creation and use of a waste-free technology. It has been found that the content of a liquid phase after interaction between NH 4 H 2 PO 4 and KCl (the molar ratio of the starting materials was 0.8 : 0.2) depends on the conversion temperatures. The chemical composition of the liquid phase can vary from 1.19 to 1.45 % of N, from 14.96 to 26.55 % of K 2 O, from 1.06 to 2.55 % of P 2 O 5 and from 13.42 to 13.71 % of Cl. The other properties of the solutions, such as pH , density and viscosity, are almost independent of temperature and meet the requirements for liquid compound fertilizers. This means that it is possible to produce a liquid fertilizer 4–5–15 grade in the post-crystallization of potassium dihydrogen phosphate remaining solution (when the molar ratio of the starting materials is 0.8 : 0.2) by adding 6 % of CO(NH 2 ) 2 wherein the crystallization temperature is 15 °C. It has been discovered that the liquid fertilizers 4–5–15 grade are efficient and give a bigger yield of plants. It increased the test plate dry weight by 78.2 %, the ash content by 41.6 % and the height of the plants by 31.2 %. DOI: http://dx.doi.org/10.5755/j01.ct.68.1.18874","PeriodicalId":22505,"journal":{"name":"the Chemical Technology","volume":"16 1","pages":"29-35"},"PeriodicalIF":0.0,"publicationDate":"2017-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87873509","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-08-22DOI: 10.5755/j01.ct.68.1.18876
J. Bendoraitiene, E. Lekniute-Kyzike, V. V. Litviak, V. V. Moskva
Two different methods, namely chemical and physical modification in the Druvather® reactor DVT5 and Krauss Maffei twin-screw extruder ZE25R x 40D UTXi were used to prepare cationically modified starches, and the properties of those were compared. The reactive extrusion process consisted of two stages. In the first one, the mixture of reaction components at the molar ratio starch : 2,3-epoxypropyltrimethyl-ammonium chloride : NaOH : H2O = 1 : 0.125 : 0.04 : 3.5 was obtained. In the second one, the derived mixture was extruded by using a twin-screw extruder. The extrusion temperature varied from 20 to 140 °C, the screw speed was 50 rpm, and the mixture feed rate was about 1.5 kg/h. Four different samples of extruded cationic starches were obtained. The main characteristics such as the degree of substitution of cationic groups (DS), reaction efficiency, particle size and the polydispersity index were determined and compared with those of a non-extruded control sample of cationic starch of similar DS. Also, the parameters well defining the behavior of samples in water, such as the swelling power (SP) and the solubility index (SOL) at 75 °C were determined for extruded and control samples. It was established that the properties of extruded and non-extruded cationic starches were different. The following observations can be drawn with respect to the obtained data: the particle size of the extruded samples is much lower and the SP values are 7–13 times lower than those of the control sample; the SOL values of the extruded samples are twice as high, reaching 76–92 %, and even might be higher.DOI: http://dx.doi.org/10.5755/j01.ct.68.1.18876
{"title":"PROPERTIES OF CATIONIC STARCHES OBTAINED BY REACTIVE EXTRUSION","authors":"J. Bendoraitiene, E. Lekniute-Kyzike, V. V. Litviak, V. V. Moskva","doi":"10.5755/j01.ct.68.1.18876","DOIUrl":"https://doi.org/10.5755/j01.ct.68.1.18876","url":null,"abstract":"Two different methods, namely chemical and physical modification in the Druvather® reactor DVT5 and Krauss Maffei twin-screw extruder ZE25R x 40D UTXi were used to prepare cationically modified starches, and the properties of those were compared. The reactive extrusion process consisted of two stages. In the first one, the mixture of reaction components at the molar ratio starch : 2,3-epoxypropyltrimethyl-ammonium chloride : NaOH : H2O = 1 : 0.125 : 0.04 : 3.5 was obtained. In the second one, the derived mixture was extruded by using a twin-screw extruder. The extrusion temperature varied from 20 to 140 °C, the screw speed was 50 rpm, and the mixture feed rate was about 1.5 kg/h. Four different samples of extruded cationic starches were obtained. The main characteristics such as the degree of substitution of cationic groups (DS), reaction efficiency, particle size and the polydispersity index were determined and compared with those of a non-extruded control sample of cationic starch of similar DS. Also, the parameters well defining the behavior of samples in water, such as the swelling power (SP) and the solubility index (SOL) at 75 °C were determined for extruded and control samples. It was established that the properties of extruded and non-extruded cationic starches were different. The following observations can be drawn with respect to the obtained data: the particle size of the extruded samples is much lower and the SP values are 7–13 times lower than those of the control sample; the SOL values of the extruded samples are twice as high, reaching 76–92 %, and even might be higher.DOI: http://dx.doi.org/10.5755/j01.ct.68.1.18876","PeriodicalId":22505,"journal":{"name":"the Chemical Technology","volume":"86 1","pages":"47-54"},"PeriodicalIF":0.0,"publicationDate":"2017-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74818264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-08-22DOI: 10.5755/J01.CT.68.1.15004
M. Holub, P. Pavlíková, M. Bálintová, M. Smolakova
The removal of sulphate ions from different types of wastewater is an environmental challenge faced by several industrial sectors such as the mining, petrochemical or metallurgical industry. Most of the current existing options are inefficient and economically unviable, particularly for acid mine drainage (AMD), where the low pH and high concentrations of heavy metals and sulphates are limiting for these processes. This work is focused on ion-exchange as one of the most common treatment methods for AMD treatment. Ion-exchange represents a very powerful technology where one or more undesirable contaminants are removed from the aqueous environment by exchange with another substance. The ideal ion-exchange solution for sulphate reduction is one that combines both anionic and cationic resins. The paper presents the results from ion-exchange experiments by the synthetic ion-exchange resin and the AMBERLITE MB20 for SO 4 2– removal from a model solution. The efficiency of the AMBERLITE MB20 resin for SO 4 2– removal from the model solution H 2 SO 4 was higher than of the PUROLITE MB400, and its efficiency decreased with increasing the concentration of sulphates from 86.6 % for the concentration 100 mg/L to 66.9 % for the concertation 1000 mg/L. DOI: http://dx.doi.org/10.5755/j01.ct.68.1.15004
{"title":"APPLICATION OF ION-EXCHANGE RESINS FOR REMOVING SULPHATE IONS FROM ACIDIC SOLUTIONS","authors":"M. Holub, P. Pavlíková, M. Bálintová, M. Smolakova","doi":"10.5755/J01.CT.68.1.15004","DOIUrl":"https://doi.org/10.5755/J01.CT.68.1.15004","url":null,"abstract":"The removal of sulphate ions from different types of wastewater is an environmental challenge faced by several industrial sectors such as the mining, petrochemical or metallurgical industry. Most of the current existing options are inefficient and economically unviable, particularly for acid mine drainage (AMD), where the low pH and high concentrations of heavy metals and sulphates are limiting for these processes. This work is focused on ion-exchange as one of the most common treatment methods for AMD treatment. Ion-exchange represents a very powerful technology where one or more undesirable contaminants are removed from the aqueous environment by exchange with another substance. The ideal ion-exchange solution for sulphate reduction is one that combines both anionic and cationic resins. The paper presents the results from ion-exchange experiments by the synthetic ion-exchange resin and the AMBERLITE MB20 for SO 4 2– removal from a model solution. The efficiency of the AMBERLITE MB20 resin for SO 4 2– removal from the model solution H 2 SO 4 was higher than of the PUROLITE MB400, and its efficiency decreased with increasing the concentration of sulphates from 86.6 % for the concentration 100 mg/L to 66.9 % for the concertation 1000 mg/L. DOI: http://dx.doi.org/10.5755/j01.ct.68.1.15004","PeriodicalId":22505,"journal":{"name":"the Chemical Technology","volume":"5 1","pages":"18-22"},"PeriodicalIF":0.0,"publicationDate":"2017-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87857365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-08-22DOI: 10.5755/J01.CT.68.1.18873
V. Bocullo, D. Vaičiukynienė, V. Vaitkevičius, A. Kantautas
This article investigates the properties of a geopolymer, an alternative binding material to the ordinary Portland cement (OPC), and their dependence on different SiO 2 /Na 2 O ratios in the system. To make the geopolymer polish coal burning fly ash consisting mainly of amorphous SiO 2 and Al 2 O 3 , it was activated with a NaOH solution. While many researches have been done on the Si/Al ratio influence, not many studies have examined the activator solution influence on geopolymer properties. Samples were made with 8 different mix compositions with the SiO 2 /Na 2 O ratio varying within 0.8–3.1. The samples were tested for compressive strength after 7, 14 and 28 days of curing. The mineral composition of each set mix was examined with XRD. Samples with the SiO 2 /Na 2 O ratio equal to 2.0 showed the highest compressive strength. The XRD of these samples showed the presence of low-crystallinity hydrosodalite and a small amount of mullite and quartz. The acceptable strength was shown by samples with the SiO 2 /Na 2 O ratio in the range of 1.5–2.5. Samples with the ratio beyond this range failed to produce enough of the necessary binding agents. DOI: http://dx.doi.org/10.5755/j01.ct.68.1.18873
{"title":"THE INFLUENCE OF THE SILICA/SODIUM RATIO ON THE FLY ASH GEOPOLYMER BINDER","authors":"V. Bocullo, D. Vaičiukynienė, V. Vaitkevičius, A. Kantautas","doi":"10.5755/J01.CT.68.1.18873","DOIUrl":"https://doi.org/10.5755/J01.CT.68.1.18873","url":null,"abstract":"This article investigates the properties of a geopolymer, an alternative binding material to the ordinary Portland cement (OPC), and their dependence on different SiO 2 /Na 2 O ratios in the system. To make the geopolymer polish coal burning fly ash consisting mainly of amorphous SiO 2 and Al 2 O 3 , it was activated with a NaOH solution. While many researches have been done on the Si/Al ratio influence, not many studies have examined the activator solution influence on geopolymer properties. Samples were made with 8 different mix compositions with the SiO 2 /Na 2 O ratio varying within 0.8–3.1. The samples were tested for compressive strength after 7, 14 and 28 days of curing. The mineral composition of each set mix was examined with XRD. Samples with the SiO 2 /Na 2 O ratio equal to 2.0 showed the highest compressive strength. The XRD of these samples showed the presence of low-crystallinity hydrosodalite and a small amount of mullite and quartz. The acceptable strength was shown by samples with the SiO 2 /Na 2 O ratio in the range of 1.5–2.5. Samples with the ratio beyond this range failed to produce enough of the necessary binding agents. DOI: http://dx.doi.org/10.5755/j01.ct.68.1.18873","PeriodicalId":22505,"journal":{"name":"the Chemical Technology","volume":"21 1","pages":"23-28"},"PeriodicalIF":0.0,"publicationDate":"2017-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87958478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-08-22DOI: 10.5755/j01.ct.68.1.18878
Y. Komarovskaya, G. Yuhnevich, V. Burd, J. Mystkowska, W. Karalus, J. Dambrowski
In this paper, studies are presented that indicate the feasibility and effectiveness of the use of the genus Bacillus microorganisms for the directional modification of physicomechanical properties (strength, nominal stretching) of polycaproamide fibers and the production of high-strength polymer-matrix composites. Bacteria of the genus Bacillus can affect the structure of the surface of the fibers by increasing the nanoroughness and the amorphous layer. It is possible to use Bacillus brevis , Bacillus subtilis , Bacillus mesentericus and others strains to improve the consumer characteristics by the direct biodegradation of polycaproamide fibers. DOI: http://dx.doi.org/10.5755/j01.ct.68.1.18878
{"title":"BACTERIA OF THE GENUS BACILLUS AS A METHOD OF DIRECTED MODIFICATION OF POLYCAPROAMIDE FIBERS","authors":"Y. Komarovskaya, G. Yuhnevich, V. Burd, J. Mystkowska, W. Karalus, J. Dambrowski","doi":"10.5755/j01.ct.68.1.18878","DOIUrl":"https://doi.org/10.5755/j01.ct.68.1.18878","url":null,"abstract":"In this paper, studies are presented that indicate the feasibility and effectiveness of the use of the genus Bacillus microorganisms for the directional modification of physicomechanical properties (strength, nominal stretching) of polycaproamide fibers and the production of high-strength polymer-matrix composites. Bacteria of the genus Bacillus can affect the structure of the surface of the fibers by increasing the nanoroughness and the amorphous layer. It is possible to use Bacillus brevis , Bacillus subtilis , Bacillus mesentericus and others strains to improve the consumer characteristics by the direct biodegradation of polycaproamide fibers. DOI: http://dx.doi.org/10.5755/j01.ct.68.1.18878","PeriodicalId":22505,"journal":{"name":"the Chemical Technology","volume":"18 1","pages":"63-67"},"PeriodicalIF":0.0,"publicationDate":"2017-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75469373","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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