microwave assisted extraction mae epa 3546

... liquid-phase microextraction with hollow fiber LLLME liquid-liquid-liquid microextraction LLE liquid-liquid extraction SPE solid-phase extraction SME solvent microextraction USEPA United States ... liquidphase microextraction techniques One is drop-based solvent microextraction including static liquid-phase microextraction (extraction solvent drop remains static during extraction) and dynamic ... sample preparation techniques include sorbent-based and solvent-based microextraction Sorbent-based microextraction is usually termed solid phase microextraction (SPME) Solvent-based microextraction...

Ngày tải lên: 17/09/2015, 17:20

... Orthogonal array design was employed to optimize both microwave- assisted extraction and supercritical fluid extraction conditions for extracting carbamates (propoxur, propham, methiocarb, ... chromatography- atmospheric pressure chemical ionization- ion trap mass spectrometry, coupled to microwave- assisted extraction technique, was also been applied to analyze the residues of N-methylcarbamate ... degradation under the extraction conditions The results indicate that although carbamates tested in this study are thermally labile, there was little observable degradation under the optimum MAE and SFE...

Ngày tải lên: 16/09/2015, 17:13

... MAE conditions for the extraction of the target According to our mode designed earlier, the four important variables selected for optimizing MAE are: (1) extraction solvents (factor A), (2) extraction ... 80οC 30 ml Extraction Level species settings Goldfish and Tortoises Sea lettuce #: Dummy factor *A: Extraction solvent; B: Extraction temperature; C: Extraction time; D: Volume of extraction ... and a 6-min of microwave heating Table 5-4 Variance analysis table in the OA (27) matrix for the optimization of MAE from tortoises A B C D Extraction solvent Extraction temperature Extraction time...

Ngày tải lên: 16/09/2015, 17:13

... OPTIMIZATION OF MICROWAVE- ASSISTED EXTRACTION AND SUPERCRITICAL FLUID EXTRACTION OF CARBAMATE PESTICIDES IN SOIL BY EXPERIMENTAL DESIGN 4.2.1 Introduction In our previous work, MAE was applied ... fluid extraction procedure g of soil was loaded into the extraction cell CO2, pure or premixed with 10% methanol, was used as the extraction fluid The extraction process started after the extraction ... factor A (extraction solvent), factor B (extraction temperature), factor C (extraction time) and the two-variable interaction B х C (interaction between extraction temperature and extraction...

Ngày tải lên: 16/09/2015, 17:13

... Liquid-Liquid Extraction Liquid-liquid extraction with dichloromethane was used for concentrating propoxur and its TPs from the water samples because of the efficiency and simplicity of this extraction ... ultrapure water were prepared with the concentrations of 0.025, 0.05, 0.10, 0.25, 0.50 and 1.0 ng/µl, respectively A set of solvent-based (methanol: water, 50:50) standards was also prepared at the same ... before analysis Spiked water samples were prepared by adding an appropriate volume of spiked solutions into the ultrapure water and natural water samples prepared as described above Hydrolysis products...

Ngày tải lên: 16/09/2015, 17:13

... USA) The stock standard solutions were prepared in acetone at concentrations of 2.0 mg/ml for each compound and stored at - 4°C Working solutions were prepared by diluting the stock solutions with ... matter before use Freshly spiked water samples were prepared by adding an appropriate volume of spiking solutions into the natural water samples prepared above and ultrapure water All the samples ... UVVIS detector and a Shimadzu C-R6A integrator The LC-API-MS analyses were performed with a Thermo Separation gradient HPLC system (Model SCM 1000) coupled to a Finnigan MAT LCQ ion-trap mass spectrometer...

Ngày tải lên: 16/09/2015, 17:13

... after extraction In recent years, some novel extraction techniques for solid matrices such as supercritical fluid extraction (SFE), microwave- assisted extraction (MAE) and accelerated-solvent extraction ... 1.3.2 Microwave- assisted Extraction (MAE) 1.3.2.1 Basic principle of MAE The principle of MAE is based on heating the extractants (mostly liquid organic solvents) in contact with the sample with microwave ... Although microwave- assisted extraction (MAE) has been successfully applied to the simultaneous extraction of toxic organic contaminants from different solid matrices, due to its high extraction...

Ngày tải lên: 16/09/2015, 17:13

... The separation is based on the normal distribution equilibria upon which conventional chromatography depends Substances are separated on the basis of their isoelectric points or pI values Separation ... DNA separation by CE, is the modified polysaccharides Since the biopolymers DNA, RNA have almost constant charge/size ratio, and electrophoresis separation can’t occur in free solution; a separation ... introduced to separate DNA on the basis of size differences In the DNA separation by CE, such a matrix can work as polymer solutions instead of cross-linked polymers Successful separation matrices...

Ngày tải lên: 11/09/2015, 14:27

Ngày tải lên: 17/02/2014, 20:20

... 1988) In most cases, there is little variation among the parts of speech The most obvious discrepancy is the slow parsing time for wansifive verbs We are not yet sure why this is, but we suspect ... relations, intending to generate plain parse trees and then examine them for relational triples in a separate step It soon became clear, however, that the LSP itself was the best tool available for ... printing out triples The LSP's Restriction Language permitted us to keep this section physically separate from the rest of the grammar and thus to treat it as an independent piece of code Having...

Ngày tải lên: 08/03/2014, 18:20

... sequencing library preparation from small amounts of DNA permits sequence determination of both DNA strands Biotechniques 2009, 46:51-52 54-57 Rohland N, Hofreiter M: Ancient DNA extraction from bones ... The rapid pace of advancement in high-throughput sequencing, coupled with advances in ancient DNA extraction and library generation [44,45] have naturally spurred the field to dream about what is ... results, discussed the implications and commented on the manuscripts at all stages KP, JK and REG prepared the manuscript Acknowledgements We would like to thank Graham Coop for suggesting the use...

Ngày tải lên: 09/08/2014, 20:22

Ngày tải lên: 21/06/2014, 01:20

... presuppositions in president Ho Chi Minh’s Independence Declaration The data was retrieved from the homepage of the Vietnamese Embassy in the United States of America The original record is published ... produced While speaking, the speaker has to control what he says so that it fits his intentions, and prepare for what to say next Every word uttered will be heard by the interlocutor, so the speaker ... okay,…except that I will miss you a lot Husband: Uhm, I’ll phone you regularly 10 Wife: OK, I’ve prepared all of your luggage here Well, I also bought some more sweaters for you Husband: My dear,...

Ngày tải lên: 14/12/2013, 00:41

... the verb is next to the subject or it is separated from the subject by other words Some confusion about subject-verb agreement may be made if there is separation between the main subject and the ... the elements of the compound subject joined by "and" ,"both and" and "all but" are considered separate entities, the subject will take a plural verb because this conjunction always suggests more ... "and" is preceded by the word "every", "each", "many", "a" or "no", the subject is considered separately As a result, a singular verb is needed E.g: Each adult and child has to pay to enter the...

Ngày tải lên: 18/12/2013, 10:04

... a clause as a message is the choice which part of the clause to be its departure point and which part is the rest The departure point of a clause is called Theme and the rest is called Rheme ... call the Themes (or Topics) of the clause Alternatively, the Theme can be seen as the "point of departure" of the message (Halliday, 1994:38) However, concentrating on Themes of clauses does not ... physical context of situation) where the referent is present, as in: a, (Sag produces a cleaver and prepares to hack off his left hand) He never actually does it b, Look out It's falling (ibid.) They...

Ngày tải lên: 22/12/2013, 12:59

... system coupled with a pulsed amperometric detection by a gold electrode For starch extraction, pellets for ethanol extraction were solubilized by heating them to 95 °C in 0.5 m NaOH for 30 After ... samples were weighed, immediately frozen in liquid nitrogen and stored at ) 80 °C until metabolite extraction Electrolyte leakage measurement Freezing tolerance was tested according to the electrolyte...

Ngày tải lên: 14/02/2014, 22:20

... buildings-related symptoms and thermal metrics was investigated by U.S Environmental Protection Agency (USEPA).41) The result suggested that a higher indoor temperature in winter was associated with an ... ABURIDASARETA HIYOWANA NIPPON Asahi Chronicle/Weekly the 20th Century, 31, 2–6 (in Japanese) 9) U.S Department of State, Second Arab Oil Embargo, 1973–1974, http://www.state.gov/r/pa/ho/ time/dr/96057.htm, ... Wypij, D., Burge, H S and Spengler, J D (2008) Evaluating buildingrelated symptoms using the US EPA BASE study results Indoor Air, 18, 335–345 Yoshida, T., Matsunaga, I., Oda, H., Miyake, Y.,...

Ngày tải lên: 17/02/2014, 22:20

Ngày tải lên: 19/02/2014, 17:20

... gratitude to Siri Tookwinas at the Department of Fisheries in Bangkok, Noparat Bamroongrugsa at the Prince of Songkhla University, Putth Songsangjinda at the Department of Fisheries in Songkhla, ... supplemented wild fry In 1973, the Department of Fisheries (DOF) began to promote semi-intensive marine shrimp culture A shrimp fry hatchery was constructed by the Department of Fisheries to provide ... treatment The production process involves four different stages: pond preparation, stocking, culturing and harvesting Pond preparation normally begins immediately after harvest and may take up to...

Ngày tải lên: 26/02/2014, 20:20