Central European Journal of Chemistry最新文献_第5页

Morpho-structural and luminescence investigations on yttrium silicate based phosphors prepared with different precipitating agents 不同沉淀剂制备硅酸钇基荧光粉的形态结构及发光研究

Central European Journal of Chemistry Pub Date : 2014-04-09 DOI: 10.2478/s11532-014-0553-z

L. Muresan, A. Cadiș, I. Perhaita, E. Indrea

{"title":"Morpho-structural and luminescence investigations on yttrium silicate based phosphors prepared with different precipitating agents","authors":"L. Muresan, A. Cadiș, I. Perhaita, E. Indrea","doi":"10.2478/s11532-014-0553-z","DOIUrl":"https://doi.org/10.2478/s11532-014-0553-z","url":null,"abstract":"AbstractYttrium silicate doped with cerium (Y2SiO5:Ce) was obtained from Y-Ce-Si based precursors prepared by the simultaneous addition of reagents (SimAdd) technique. The synthesis of the precursors was done in well controlled conditions using ammonium oxalate, ammonium carbonate or urea as precipitating agents. Results regarding the influence of precipitating agents on the morpho structural and photoluminescent characteristics of Y2SiO5:Ce are reported. The TG analysis in correlation with EGA, FT-IR and XRD investigations reveals the formation of oxalate, hydroxy-carbonate or hydroxy-nitrate based compounds, the same as the conversion of the precursors to well crystallized yttrium silicate. XRD patterns show that the precursors are amorphous except for the sample prepared with ammonium oxalate. Depending on the precipitation conditions, the phosphors phase composition varies from single phase (X2-Y2SiO5) to a mixture of phases (X2-Y2SiO5, X1-Y2SiO5, Y2O3). Under UV excitation, phosphors exhibit the specific blue emission of cerium with an intensity that varies from 175.8% (urea) to 96.0% (ammonium carbonate) and to 78.5% (ammonium oxalate). The emission intensity depends on the phase purity and order degree of the phosphors. PACS Classification codes:78.55 Hx, 81.20Fw\u0000","PeriodicalId":9888,"journal":{"name":"Central European Journal of Chemistry","volume":"19 1","pages":"1023-1031"},"PeriodicalIF":0.0,"publicationDate":"2014-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78041993","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}

引用次数: 5

New genetic insights to consider coffee waste as feedstock for fuel, feed, and chemicals 新的遗传学见解考虑咖啡废料作为燃料，饲料和化学品的原料

Central European Journal of Chemistry Pub Date : 2014-04-09 DOI: 10.2478/s11532-014-0550-2

R. Summers, Sridhar Gopishetty, S. Mohanty, M. Subramanian

引用次数: 16

Biocatalytic designs for the conversion of renewable glycerol into glycerol carbonate as a value-added product 将可再生甘油转化为碳酸甘油作为增值产品的生物催化设计

Central European Journal of Chemistry Pub Date : 2014-04-09 DOI: 10.2478/s11532-014-0547-x

M. Tudorache, George Ghemes, Andreea Nae, E. Matei, I. Mercioniu, E. Kemnitz, Benjamin S. Ritter, S. Coman, V. Pârvulescu

{"title":"Biocatalytic designs for the conversion of renewable glycerol into glycerol carbonate as a value-added product","authors":"M. Tudorache, George Ghemes, Andreea Nae, E. Matei, I. Mercioniu, E. Kemnitz, Benjamin S. Ritter, S. Coman, V. Pârvulescu","doi":"10.2478/s11532-014-0547-x","DOIUrl":"https://doi.org/10.2478/s11532-014-0547-x","url":null,"abstract":"A comparative study of two different biocatalytic models, e.g. enzyme immobilized on magnetic particles (EIMP) and cross-linking enzyme aggregates onto magnetic particles (CLEMPA) was performed. The first model was designed as enzyme-immobilized on the magnetic particles surface (EIMP). The second model was constructed as a network structure with the enzyme aggregates and magnetic particles placed into the nodes and polyglutaraldehyde cross-linker as the network ledges. The design was called cross-linking enzyme aggregates onto magnetic particles (CLEMPA). The biocatalysts were prepared using lipase enzyme from Aspergillus niger for catalyzing the glycerol (Gly) conversion to glycerol carbonate (GlyC). The biocatalyst characteristics for both designs (EIMP and CLEMPA) were evaluated using scanning electron microscopy (SEM), laser light scattering (LLS) and UV-Vis techniques. The EIMP model was strongly influenced by the composition of the polymeric layer covering the particles surface, while the size of the magnetic particles affected mostly the CLEMPA design. Also, the biocatalytic capacity of the tested models was evaluated as maximum 52% Gly conversion with 90% GlyC selectivity for EIMP, and 73% Gly conversion with 77% GlyC selectivity for CLEMPA. Both biocatalytic models were successfully used to prepare GlyC from “crude” glycerol collected directly from the biodiesel process (e.g. 49% Gly conversion with 91% GlyC selectivity for EIMP and 70% Gly conversion with 80% GlyC selectivity for CLEMPA).","PeriodicalId":9888,"journal":{"name":"Central European Journal of Chemistry","volume":"172 1","pages":"1262-1270"},"PeriodicalIF":0.0,"publicationDate":"2014-04-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77521061","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}

引用次数: 8

Analytical methods for determination of benzodiazepines. A short review 苯二氮卓类药物的分析方法。简短回顾

Central European Journal of Chemistry Pub Date : 2014-04-03 DOI: 10.2478/s11532-014-0551-1

Paulina Szatkowska, M. Koba, Piotr Kośliński, Jacek Wandas, T. Bączek

引用次数: 24

Catalytic production of oxygenated additives by glycerol etherification 甘油醚化催化生产含氧添加剂

Central European Journal of Chemistry Pub Date : 2014-04-03 DOI: 10.2478/s11532-014-0546-y

C. Cannilla, G. Bonura, L. Frusteri, F. Frusteri

引用次数: 11

Controlled pesticide release from biodegradable polymers 控制农药从可生物降解聚合物中释放

Central European Journal of Chemistry Pub Date : 2014-04-01 DOI: 10.2478/s11532-013-0405-2

Anamika Roy, Sunil Kumar Singh, J. Bajpai, A. Bajpai

引用次数: 214

Cultivating conditions optimization of the anaerobic digestion of corn ethanol distillery residuals using response surface methodology 响应面法优化玉米乙醇蒸馏渣厌氧消化培养条件

Central European Journal of Chemistry Pub Date : 2014-03-19 DOI: 10.2478/s11532-014-0542-2

L. Gyenge, B. Raduly, S. Crognale, S. Lányi, Beáta Ábrahám

{"title":"Cultivating conditions optimization of the anaerobic digestion of corn ethanol distillery residuals using response surface methodology","authors":"L. Gyenge, B. Raduly, S. Crognale, S. Lányi, Beáta Ábrahám","doi":"10.2478/s11532-014-0542-2","DOIUrl":"https://doi.org/10.2478/s11532-014-0542-2","url":null,"abstract":"This study investigated the individual and interactive effects of three factors — temperature, inoculum/substrate ratio (ISR) and inoculum typology — on the anaerobic digestion of corn ethanol distillery wastewater. Biochemical methane potential assays planned with factorial design with two independent quantitative variables on three levels (ISR: 1:1, 2:1 and 3:1; temperature: 30°C, 33.5°C, 37°C) and one independent qualitative variable (inoculum type: suspended, granular, mixed) have been performed. Response Surface Methodology has been used to study the effect of the factors with the aim of maximizing the specific methane yields (YCH4) obtainable with this substrate. The results show that all three investigated factors influence in a significant matter the YCH4, the ISR having the strongest effect on it. The temperature has significant influence on the YCH4 only in combination with high ISR values. The optimal conditions for the maximum YCH4 (551 mL CH4 g−1 VSadded) have been found at 37°C operating temperature, ISR=3:1 and using granular inoculum. These conditions gave rise to a 4-fold increase of YCH4 with respect to the worst combination of factors (YCH4=129 mL g−1 VSadded for the suspended inoculum type, at 30°C and ISR=1:1). The results improve the knowledge on the digestion of this substrate, providing information for successful process up-scaling.","PeriodicalId":9888,"journal":{"name":"Central European Journal of Chemistry","volume":"39 1","pages":"868-876"},"PeriodicalIF":0.0,"publicationDate":"2014-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86190491","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}

引用次数: 10

Holographic grating inscription in DR1: DNA-CTMA thin films: the puzzle of time scales DR1: DNA-CTMA薄膜中的全息光栅铭文:时间尺度的谜题

Central European Journal of Chemistry Pub Date : 2014-03-19 DOI: 10.2478/s11532-014-0543-1

G. Pawlik, W. Radosz, A. Mituś, J. Myśliwiec, A. Miniewicz, F. Kajzar, I. Rău

引用次数: 6

Thermal oxidation of irradiated magnetic fluids and their component surfactants and dispersing oils 辐照磁流体及其组成表面活性剂和分散油的热氧化

Central European Journal of Chemistry Pub Date : 2014-03-19 DOI: 10.2478/s11532-014-0538-y

T. Zaharescu, R. Setnescu, I. Borbath

引用次数: 2

Chemical characterization of particulate matter (PM) and source apportionment study during winter and summer period for the city of Kozani, Greece 希腊Kozani市冬季和夏季颗粒物(PM)化学特征及来源解析研究

Central European Journal of Chemistry Pub Date : 2014-03-13 DOI: 10.2478/s11532-014-0531-5

E. Tolis, D. Saraga, George Z. Ammari, E. Gkanas, Theofilos Gougoulas, Christina C. Papaioannou, Anastasios K. Sarioglou, Eleftherios Kougioumtzidis, Athina Skemperi, J. Bartzis

{"title":"Chemical characterization of particulate matter (PM) and source apportionment study during winter and summer period for the city of Kozani, Greece","authors":"E. Tolis, D. Saraga, George Z. Ammari, E. Gkanas, Theofilos Gougoulas, Christina C. Papaioannou, Anastasios K. Sarioglou, Eleftherios Kougioumtzidis, Athina Skemperi, J. Bartzis","doi":"10.2478/s11532-014-0531-5","DOIUrl":"https://doi.org/10.2478/s11532-014-0531-5","url":null,"abstract":"Eordaia basin located in northwest of Greece, comprises an area which is characterized by intense energy related activities, including coal burning at four power plants and the associated mining operations. Air samples of inhalable (PM10) and respirable particles (PM2.5) were collected in cold and warm periods in 2010 at an urban background site of Kozani, the major city and capital of the region which is located close to the power plants. Particulate matter concentration, particle-bound polycyclic aromatic hydrocarbons and anionic species concentrations were determined using gravimetric, GC-MS in SIM mode and Ion Chromatography analysis, respectively. For the cold period, the mean PM10 and PM2.5 mass concentration was found to be 19.62 and 14.68 µg m−3, respectively. Correspondingly, for the warm period, the mean PM10 and PM2.5 values were 35.29 and 25.75 µg m−3, respectively. In general, the results indicated that the major sources of air pollution in Kozani are traffic, combustion from agricultural activities and lignite power plants emissions, contributing by different percentages to each particle fraction.","PeriodicalId":9888,"journal":{"name":"Central European Journal of Chemistry","volume":"10 1","pages":"643-651"},"PeriodicalIF":0.0,"publicationDate":"2014-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81325205","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}

引用次数: 33