Proceedings of the Estonian Academy of Sciences. Chemistry最新文献_第2页

Solvent extraction and separation of lanthanoids with mixtures of chelating extractant and 4-(2-pyridylazo)-resorcin 螯合萃取剂与4-(2-吡啶偶氮)间苯二酚混合萃取分离类镧

Proceedings of the Estonian Academy of Sciences. Chemistry Pub Date : 2006-01-01 DOI: 10.3176/chem.2006.4.03

M. Atanassova

引用次数: 6

Degradation of lignins by wet oxidation: model water solutions 湿氧化法降解木质素:模型水溶液

Proceedings of the Estonian Academy of Sciences. Chemistry Pub Date : 2006-01-01 DOI: 10.3176/chem.2006.3.02

M. Kindsigo, J. Kallas

{"title":"Degradation of lignins by wet oxidation: model water solutions","authors":"M. Kindsigo, J. Kallas","doi":"10.3176/chem.2006.3.02","DOIUrl":"https://doi.org/10.3176/chem.2006.3.02","url":null,"abstract":"Nowadays many paper industries are faced with the problem of wastewaters being badly biodegradable because of tannins, lignins, etc. Wet oxidation (WO) is an appropriate met hod for the destruction of very complex, multi-dimensional, and permanent compounds. This paper studies the WO of lignin water as a model case with the aim of degrading lignin and enhancing water biodegradability. The experiments were performed at various temperatures (110-190 °C), partial oxygen pressures (0.5-1.5 MPa), and pH values (5, 9, and 12) in a batch stainless steel high pressure reactor. The experiments showed that increasing the temperature improved the processes efficiency. At the lowest temperature tested 75% lignin reduction was detected and a temperature increase improved the lignin removal to 100% at 190 °C. The effect of temperature on the COD removal rate was lower, but detectable: 20% of organics was oxidized at 110 °C, but 53% at 190 °C. Oxygen partial pressure changes affected the process results modestly. Lignin removal increased by about 10% and COD removal by 4% with an oxygen partial pressure increase from 0.5 to 1.5 MPa. The effect of pH occurred mostly on lignin removal. Increasing the pH enhanced the lignin removal efficiency from 60% to nearly 100%. In all cases, a good biodegradability (BOD/COD ratio over 0.5) was achieved starting at a temperature of 150 °C, pH 9, irrespective of the experimented pressures. The biodegradability (BOD/COD) of the remaining organic matter increased during WO and approached almost 1 at the highest temperature of 190 °C.","PeriodicalId":20551,"journal":{"name":"Proceedings of the Estonian Academy of Sciences. Chemistry","volume":"47 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2006-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73351672","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: 25

Investigation of different schemes for anaerobic treatment of food industry wastes in Estonia 爱沙尼亚食品工业废弃物厌氧处理不同方案的调查

Proceedings of the Estonian Academy of Sciences. Chemistry Pub Date : 2006-01-01 DOI: 10.3176/chem.2006.1.02

Viktoria Blonskaja, Tarmo Vaalu

引用次数: 19

Preparation of chitosan powder and investigation of its properties 壳聚糖粉体的制备及其性能研究

Proceedings of the Estonian Academy of Sciences. Chemistry Pub Date : 2006-01-01 DOI: 10.3176/chem.2006.2.04

M. Laka, S. Chernyavskaya

引用次数: 13

Interaction of tritium-labelled dopamine transporter inhibitor PE2I with mice striatal membrane fragments 氚标记多巴胺转运蛋白抑制剂PE2I与小鼠纹状体膜片段的相互作用

Proceedings of the Estonian Academy of Sciences. Chemistry Pub Date : 2006-01-01 DOI: 10.3176/chem.2006.3.05

V. Stepanov, J. Järv

{"title":"Interaction of tritium-labelled dopamine transporter inhibitor PE2I with mice striatal membrane fragments","authors":"V. Stepanov, J. Järv","doi":"10.3176/chem.2006.3.05","DOIUrl":"https://doi.org/10.3176/chem.2006.3.05","url":null,"abstract":"Interaction of 3 H-labelled N-(3-iodoprop-2E-enyl)-2β-carbomethoxy-3β-(4-methyl- phenyl)nortropane (( 3 H)PE2I), a novel tritium-labelled ligand for tracing dopamine transporter protein, with mice striatal membrane fragments was studied under equilibrium conditions. Radio- ligand binding with a homogeneous population of binding sites was observed in these brain membrane fragments and characterized by the Kd value 22 ± 5 nM and Bmax = 0.12 ± 0.02 pmol/mg tissue. The specific binding of ( 3 H)PE2I was effectively displaced by unlabelled PE2I as well as GBR 12935, also known as an inhibitor of the transporter protein. Rather similar pIC 50 values, 7.1 ± 0.3 and 6.9 ± 0.3, respectively, were obtained for these ligands in displacement experiments. This is in agreement with similar pharmacological effects of these ligands on dopaminergic neurons. After correction by the Cheng-Prusoff equation the displacement study yielded the Kd value of 40 nM for PE2I. The difference between the Kd values for PE2I obtained from the direct binding study and displacement experiments seems to point to some specific feature of the mechanism of PE2I interaction with the transporter sites and will be clarified through systematic kinetic study of the radioligand binding.","PeriodicalId":20551,"journal":{"name":"Proceedings of the Estonian Academy of Sciences. Chemistry","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2006-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86584541","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: 1

Increasing the biodegradability of rocket fuel polluted groundwater by means of chemical oxidation processes 利用化学氧化法提高火箭燃料污染地下水的生物可降解性

Proceedings of the Estonian Academy of Sciences. Chemistry Pub Date : 2006-01-01 DOI: 10.3176/chem.2006.4.02

J. Reinik, J. Kallas

{"title":"Increasing the biodegradability of rocket fuel polluted groundwater by means of chemical oxidation processes","authors":"J. Reinik, J. Kallas","doi":"10.3176/chem.2006.4.02","DOIUrl":"https://doi.org/10.3176/chem.2006.4.02","url":null,"abstract":"Highly toxic residues of rocket fuel have been detected in the groundwater of an abandoned military missile base in north-west Estonia. The growth of indigenous rocket fuel- degrading bacteria in the polluted groundwater is strongly inhibited by a high concentration of pollutants in the groundwater. Two chemical oxidation processes, ozonation and catalytic wet oxidation (CWO), were studied for the treatment of such groundwater. The ozonation experiments were carried out in a wetted-wall column and the CWO experiments were conducted in an autoclave in the presence of granulated activated carbon. The ozone-water contact column operated at laboratory temperature whilst in CWO the operational variables ranged as follows: temperature from 413 to 446 K, oxygen pressure from 0.4 to 1 MPa. Both processes degraded the primary rocket fuel pollutant (dimethylanilines) and increased biodegradability. The solution remaining after ozonation and CWO contained mainly organic acids. Despite the formation of refractory compounds, the residual water can be treated in bioprocesses without complications b ecause organic acids are easily biodegradable.","PeriodicalId":20551,"journal":{"name":"Proceedings of the Estonian Academy of Sciences. Chemistry","volume":"14 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2006-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81844661","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: 0

Biobased polymer composites for films and coatings 用于薄膜和涂料的生物基聚合物复合材料

Proceedings of the Estonian Academy of Sciences. Chemistry Pub Date : 2006-01-01 DOI: 10.3176/chem.2006.2.03

Dace Erkske, Ilze Viskere, A. Dzene, V. Tupureina, L. Savenkova

引用次数: 12

Synthesis and properties of cross-linked poly(ester urethanes) from poly(lactide) triols and poly(caprolactone) diols 聚乳酸三醇和聚己内酯二醇交联聚酯聚氨酯的合成及性能研究

Proceedings of the Estonian Academy of Sciences. Chemistry Pub Date : 2006-01-01 DOI: 10.3176/chem.2006.2.05

B. Lazdiņa, U. Stirna, V. Tupureina, A. Dzene, I. Sevastyanova

引用次数: 3

Composition of the essential oil of Artemisia absinthium L. of different geographical origin 不同产地苦艾精油的成分分析

Proceedings of the Estonian Academy of Sciences. Chemistry Pub Date : 2006-01-01 DOI: 10.3176/chem.2006.3.04

A. Orav, A. Raal, E. Arak, M. Müürisepp, T. Kailas

{"title":"Composition of the essential oil of Artemisia absinthium L. of different geographical origin","authors":"A. Orav, A. Raal, E. Arak, M. Müürisepp, T. Kailas","doi":"10.3176/chem.2006.3.04","DOIUrl":"https://doi.org/10.3176/chem.2006.3.04","url":null,"abstract":"Variations in the essential oil composition of Artemisia absinthium L. obtained from different geographical areas of Europe were determined using capillary gas chromatographic and mass spectrometric analysis methods. The oils from air-dried wormwood were obtained in yields of 0.1-1.1%. The Absinthii herba grown in Estonia corresponded to the EP standards in the aspect of the essential oil contents. A total of 107 components were identified, representing over 85% of the total yield of oil. The principal components in the oils were sabinene (0.9-30.1%), myrcene (0.1-38.9%), 1,8-cineole (0.1-18.0%), artemisia ketone (0-14.9%), linalool and -thujone (1.1-10.9%), -thujone (0.1-64.6%), trans-epoxyocimene (0.1-59.7%), trans-verbenol (0-11.7%), carvone (0-18.5%), (E)-sabinyl acetate ( 0-70.5%), curcumene (0-7.0%), neryl butyrate (0.1-13.9%), neryl 2-methyl- butanoate (0.1-9.2%), neryl 3-methylbutanoate (0.4-7.3%), and chamazulene (0-6.6%). Mono- terpenes were predominant (44.0-67.9%) in the oils from Scotland, Estonia (2000, 2002), Moldova, and Hungary. In the other oils studied oxygenated monoterpenes (41.2-93.9%) were found to predominate. The highest content of oxygenated sesquiterpenes (11.9-29.8%) was found in the oils from Italy, Latvia, Lithuania, and Germany. Armenian oil contained more chamazulene (6.6%) than the other samples studied (0-2.1%). Four chemotypes were found to be characteristic of A. absinthium growing in Europe: sabinene and myrcene rich oil, - and -thujone rich oil, epoxyocimene rich oil, and (E)-sabinyl acetate rich oil. Some mixed chemotypes were also f ound.","PeriodicalId":20551,"journal":{"name":"Proceedings of the Estonian Academy of Sciences. Chemistry","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2006-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80714742","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: 77

Extraction and quantification of hybrid carrageenans from the biomass of the red algae Furcellaria lumbricalis and Coccotylus truncatus 从红藻褐藻和尾藻生物量中提取和定量杂交角叉菜胶

Proceedings of the Estonian Academy of Sciences. Chemistry Pub Date : 2006-01-01 DOI: 10.3176/chem.2006.1.04

R. Tuvikene, K. Truus, M. Vaher, T. Kailas, P. Kersen

{"title":"Extraction and quantification of hybrid carrageenans from the biomass of the red algae Furcellaria lumbricalis and Coccotylus truncatus","authors":"R. Tuvikene, K. Truus, M. Vaher, T. Kailas, P. Kersen","doi":"10.3176/chem.2006.1.04","DOIUrl":"https://doi.org/10.3176/chem.2006.1.04","url":null,"abstract":"The main isolation procedures (extraction, alkali modification, and precipitation) of hybrid carrageenan blend from seaweeds of the Kassari algal stratum (the Baltic Sea, Estonia) were quantitatively investigated. In the case of all extracting agents (water, KOH and NaOH solutions) used, a sharp rise occurred in the extracting rate during the first 2 h. Pure water was the most efficient extracting medium for carrageenans from the biomass of Furcellaria lumbricalis- Coccotylus truncatus with regard to yield but certainly not gelling properties (gel strength) of polysaccharides extracted. Long-time alkali extraction causes great losses due to degradation of carrageenans; however, alkali treatment is an obligatory step for the isolation of high-quality gelling galactans from the Kassari algal stratum, resulting in a more than 3-fold increase in gel strength. In the case of a typical algal blend from this stratum (69% F. lumbricalis and 10% C. truncatus), the most effective medium for the isolation of carrageenan mixture is 0.05 M KOH solution and the preferred duration of extraction is 3-4 h.","PeriodicalId":20551,"journal":{"name":"Proceedings of the Estonian Academy of Sciences. Chemistry","volume":"389 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2006-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80797106","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: 49