Procedia Chemistry最新文献_第4页

The Role and Efficiency of Ammonium Sulphate Precipitation in Purification Process of Papain Crude Extract 硫酸铵沉淀在木瓜蛋白酶粗提物纯化过程中的作用及效果

Procedia Chemistry Pub Date : 2016-01-01 DOI: 10.1016/j.proche.2016.01.020

Maria Goretti M. Purwanto

引用次数: 31

Physical Properties of Highly Active Liquor Containing Molybdate Solids 含钼酸盐固体高活性液的物理性质

Procedia Chemistry Pub Date : 2016-01-01 DOI: 10.1016/j.proche.2016.10.004

Barbara Dunnett , Tracy Ward , Rachel Roberts , Jonathan Cheesewright

{"title":"Physical Properties of Highly Active Liquor Containing Molybdate Solids","authors":"Barbara Dunnett , Tracy Ward , Rachel Roberts , Jonathan Cheesewright","doi":"10.1016/j.proche.2016.10.004","DOIUrl":"10.1016/j.proche.2016.10.004","url":null,"abstract":"<div>The reprocessing of irradiated nuclear fuel at Sellafield produces a nitric acid based Highly Active Liquor (HAL) waste. The liquor, containing fission products and process additives, is concentrated in an evaporator in order to reduce the volume and is then stored in Highly Active Storage Tanks (HASTs) prior to vitrification. Caesium phosphomolybdate (CPM) is precipitated during the evaporation process and can convert to zirconium molybdate (ZM) during storage.During Post Operational Clean Out (POCO) of the HASTs, it is expected that their highly active content will be reduced by repeated cycles of washing using nitric acid and other reagents. Initial washings are likely to have a chemical composition comparable to concentrated HAL, becoming more dilute during the wash-out process. It is expected that the wash-out process will also recover significant quantities of molybdate solids (ZM, CPM or a mixture) from the HASTs.In order to determine the processing challenges from such washings during POCO, the physical properties of varying concentrations of non-active HAL simulants containing molybdate solids have recently been measured by the UK's National Nuclear Laboratory. The following measurements are presented and discussed:<ul><li>•Particle size distribution</li><li>•Density</li><li>•Settling behaviour of solids</li><li>•Voidage of settled sediment beds</li><li>•Viscosity</li><li>•Yield stress</li><li>•Influence of ZM morphology on physical properties</li></ul></div>","PeriodicalId":20431,"journal":{"name":"Procedia Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.proche.2016.10.004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82022270","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Structure and Catalytic Mechanism of 3-Ketosteroid Dehydrogenases 3-酮类固醇脱氢酶的结构与催化机理

Procedia Chemistry Pub Date : 2016-01-01 DOI: 10.1016/j.proche.2016.01.006

Bauke W. Dijkstra , Niels van Oosterwijk , Ali Rohman

引用次数: 9

Mass Transport Analysis in Linear Microdialysis Probes Utilizing Structural Characterization Technique 利用结构表征技术分析线性微透析探针的质量输运

Procedia Chemistry Pub Date : 2016-01-01 DOI: 10.1016/j.proche.2016.03.017

Kho Chun Min , Zainal Arifin Ahmad , Siti Kartini Enche Ab Rahim , Norazharuddin Shah Abdullah

{"title":"Mass Transport Analysis in Linear Microdialysis Probes Utilizing Structural Characterization Technique","authors":"Kho Chun Min , Zainal Arifin Ahmad , Siti Kartini Enche Ab Rahim , Norazharuddin Shah Abdullah","doi":"10.1016/j.proche.2016.03.017","DOIUrl":"10.1016/j.proche.2016.03.017","url":null,"abstract":"<div>Microdialysis is a separation technique widely used for sampling and monitoring purposes. Microdialysis requires a (microdialysis) probe to be inserted to the designated area of study. Separation procedure is completed by using a selective semi-permeable membrane attached to the microdialysis proe. Despite being a well-established technique, there are still issues regarding the performance of the microdialysis probe. The biggest issue is arguably that the concentration of solutes collected via microdialysis sampling represents only 20-30% of the original concentration from the sampling site. This issue can be resolved by understanding mass transport phenomena within the microdialysis probe and its surroundings. One straightforward, yet sustainable way to analyze mass transport is through the use of computational modelling. In this paper, a mathematical framework, representing glucose recovery from a quiescent media using a microdialysis probe of linear design was described. Governing equations, boundary conditions and operational parameters were justifiably selected. Different diffusion coefficients were used to describe the mass transport through the quiescent media, semi-permeable membrane and the probe's lumen. Subsequently, the influence of some identified parameters, on the overall recovery is examined. Scanning electron microscopy imaging was used to study the physical characteristics of the microdialysis membrane, thus being utilized to estimate the diffusion coefficient values. The impact of using different diffusion coefficient values on the overall recovery was also discussed.</div>","PeriodicalId":20431,"journal":{"name":"Procedia Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.proche.2016.03.017","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85152537","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Used Mixed Oxide Fuel Reprocessing at RT-1 Plant RT-1核电厂的废混合氧化物燃料后处理

Procedia Chemistry Pub Date : 2016-01-01 DOI: 10.1016/j.proche.2016.10.028

Dmitrii Kolupaev , Michail Logunov , Alexader Mashkin , Konstantin Bugrov , Konstanin Korchenkin , Andrei Shadrin , Konstanin Dvoeglazov

{"title":"Used Mixed Oxide Fuel Reprocessing at RT-1 Plant","authors":"Dmitrii Kolupaev , Michail Logunov , Alexader Mashkin , Konstantin Bugrov , Konstanin Korchenkin , Andrei Shadrin , Konstanin Dvoeglazov","doi":"10.1016/j.proche.2016.10.028","DOIUrl":"10.1016/j.proche.2016.10.028","url":null,"abstract":"<div>Reprocessing of the mixed uranium-plutonium spent nuclear fuel of the BN-600 reactor was performed at the RT-1 plant twice, in 2012 and 2014. In total, 8 fuel assemblies with a burn-up from 73 to 89 GW day/t and the cooling time from 17 to 21 years were reprocessed. The reprocessing included the stages of dissolution, clarification, extraction separation of U and Pu with purification from the fission products, refining of uranium and plutonium at the relevant refining cycles. Dissolution of the fuel composition of MOX UNF in nitric acid solutions in the presence of fluoride ion has occurred with the full transfer of actinides into solution. Due to the high content of Pu extraction separation of U and Pu was carried out on a nuclear-safe equipment designed for the reprocessing of highly enriched U spent nuclear fuel and Pu refining. Technological processes of extraction, separation and refining of actinides proceeded without deviations from the normal mode. The output flow of the extraction outlets in their compositions corresponded to the regulatory norms and remained at the level of the compositions of the streams resulting from the reprocessing of fuel types typical for the RT-1 plant. No increased losses of Pu into waste have been registered during the reprocessing of BN-600 MOX UNF an compare with VVER-440 uranium UNF reprocessing.</div>","PeriodicalId":20431,"journal":{"name":"Procedia Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.proche.2016.10.028","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85267869","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

Application of the Pyrochemical DOS, Developed by the CEA, within Reprocessing of CERCER Transmutation Fuel Targets CEA研制的热化学DOS在CERCER嬗变燃料靶件后处理中的应用

Procedia Chemistry Pub Date : 2016-01-01 DOI: 10.1016/j.proche.2016.10.060

E. Mendes , T. Ducasse , M. Miguirditchian , M. Bertrand

{"title":"Application of the Pyrochemical DOS, Developed by the CEA, within Reprocessing of CERCER Transmutation Fuel Targets","authors":"E. Mendes , T. Ducasse , M. Miguirditchian , M. Bertrand","doi":"10.1016/j.proche.2016.10.060","DOIUrl":"10.1016/j.proche.2016.10.060","url":null,"abstract":"<div>Pyrochemical technology using high-temperature molten salts and molten metal media presents a potential interest for an overall separation and transmutation strategy for long-lived radionuclides. Within the frame of the two French acts on radioactive waste management, a pyrochemical R&D program was launched at the CEA Marcoule in the late 90's. The second step is the actinides back-extraction, which consists in a liquid/liquid oxidative stripping of the An from aluminium matrix into molten chloride media. The DOS process has been successfully demonstrated for treatment of oxide type fuels within the last years: the core of the process has been already assessed and the studies have shown high selectivity and a quantitative recovery of actinides.Within the framework of the SACSESS European research program, the pyrochemical activities focused on applications of the DOS process to reprocess CERCER transmutation targets. These particular type of fuels consist of a mixture of minor actinides (MA) oxides diluted in an inert (oxide MgO) matrices. The behaviour of matrices material was first investigated regarding the solubility in the fluoride salt, starting from both oxide powders or sintered pellets. Further investigations focused on the reductive extraction behaviour of Mg in metallic Al. The impact of Mg on the efficiency of An reductive extraction was also studied using uranium simulating the behaviour of MA oxides.</div>","PeriodicalId":20431,"journal":{"name":"Procedia Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.proche.2016.10.060","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83780815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Storage of Defective Fuel Pins in SFR Core 有缺陷的燃料销存放在SFR堆芯中

Procedia Chemistry Pub Date : 2016-01-01 DOI: 10.1016/j.proche.2016.10.053

Dan-Tiberiu Costin , Lionel Desgranges , Teodora Retegan , Christian Ekberg

引用次数: 3

Uranium and Plutonium Extraction by N,N-dialkylamides Using Multistage Mixer-settler Extractors 多级混合沉降萃取器萃取N,N-二烷基酰胺提取铀和钚

Procedia Chemistry Pub Date : 2016-01-01 DOI: 10.1016/j.proche.2016.10.022

Yasutoshi Ban, Shinobu Hotoku, Nao Tsutsui, Asuka Suzuki, Yasuhiro Tsubata, Tatsuro Matsumura

{"title":"Uranium and Plutonium Extraction by N,N-dialkylamides Using Multistage Mixer-settler Extractors","authors":"Yasutoshi Ban, Shinobu Hotoku, Nao Tsutsui, Asuka Suzuki, Yasuhiro Tsubata, Tatsuro Matsumura","doi":"10.1016/j.proche.2016.10.022","DOIUrl":"10.1016/j.proche.2016.10.022","url":null,"abstract":"<div>N,N-Dialkylamides (monoamides) are known as extractants for U and Pu, and many studies have been carried out mainly by single-stage batch method. We have focused on two monoamides: N,N-di(2-ethylhexyl)-2,2-dimethylpropanamide (DEHDMPA) and N,N-di(2-ethylhexyl)butanamide (DEHBA), and proposed a multistage extraction process for recovering U and Pu by these monoamides. A continuous counter-current experiment was carried out to demonstrate the validity of this process. This process consisted of two cycles, and the 1st cycle and the 2nd cycle employed DEHDMPA and DEHBA as extractants, respectively. The feed solution for the 1st cycle was 5.1mol/dm3 (M) nitric acid containing 0.92M U, 1.6mM Pu, and 0.6mM Np. The raffinate collected in the 1st cycle was used as the feed for the 2nd cycle. The ratios of U recovered in the U fraction and U-Pu fraction were 99.1% and 0.8%, respectively, and the ratios of U in the used solvents were <0.04%. The ratio of Pu recovered in the U-Pu fraction was 99.7%, and the ratio of Pu in the used solvents was in the order of 10–3–10–4%. The concentration ratio of U with respect to Pu in the U-Pu fraction was 9, and this indicated that Pu was not isolated. The decontamination factor of U with respect to Pu in the U fraction was obtained as 4.5×105. These results supported the validity of the proposed process.</div>","PeriodicalId":20431,"journal":{"name":"Procedia Chemistry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.proche.2016.10.022","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80345730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5

The Assessment of Cr(VI) Removal by Iron Oxide Nanosheets and Nanowires Synthesized by Thermal Oxidation of Iron in Water Vapour 水蒸气中铁的热氧化合成氧化铁纳米片和纳米线去除Cr(VI)的效果评价

Procedia Chemistry Pub Date : 2016-01-01 DOI: 10.1016/j.proche.2016.03.057

Faisal Budiman , Tan Wai Kian , Khairunisak Abdul Razak , Atsunori Matsuda , Zainovia Lockman

引用次数: 16

Structural and Electrical Characterizations of CuNi Thin Film Resistors CuNi薄膜电阻器的结构和电学特性

Procedia Chemistry Pub Date : 2016-01-01 DOI: 10.1016/j.proche.2016.03.061

Nurul Khalidah Yusop , Nurulakmal Mohd Shariff , See Chin Chow , Ahmad Badri Ismail

引用次数: 4