scholarly journals Application of a Microfluidic Gas-to-Liquid Interface for Extraction of Target Amphetamines and Precursors from Air Samples

Micromachines ◽  
2020 ◽  
Vol 11 (3) ◽  
pp. 315
Author(s):  
Michael Collins ◽  
Murat Gel ◽  
Chris Lennard ◽  
Val Spikmans ◽  
Shari Forbes ◽  
...  
Keyword(s):  
Emergency Services ◽  
Extraction Efficiency ◽  
Vapour Phase ◽  
Initial Study ◽  
Extraction Process ◽  
Microfluidic Channels ◽  
Gas Generation ◽  
Detection Systems ◽  
Efficiency And Effectiveness ◽  
Gas To Liquid

The investigation of clandestine laboratories poses serious hazards for first responders, emergency services, investigators and the surrounding public due to the risk of exposure to volatile organic compounds (VOCs) used in the manufacture of illicit substances. A novel gas sampling interface using open microfluidic channels that enables the extraction of VOCs out of the gas phase and into a liquid, where it can be analysed by conventional detection systems, has recently been developed. This paper investigates the efficiency and effectiveness of such a gas-to-liquid (GTL) extraction system for the extraction of amphetamine-type substances (ATS) and their precursors from the vapour phase. The GTL interface was evaluated across a range of different ATS and their precursors (methamphetamine, dimethylamphetamine, N-formylmethamphetamine, benzaldehyde, phenyl-2-propanone, ephedrine and pseudoephedrine) at concentrations ranging between 10 and 32 mg m−3. These gas samples were produced by a gas generation system directly in Tedlar® bags and gas canisters for controlled volume sampling. When using gas sampled from Tedlar® bags, four of the seven compounds were able to be extracted by the GTL interface, with the majority of the VOCs having extraction yields between 0.005% and 4.5%, in line with the results from an initial study. When samples were taken from gas canisters, only benzaldehyde was able to be detected, with extraction efficiencies between 0.2% and 0.4%. A custom-built mount for the GTL interface helped to automate the extraction process, with the aim of increasing extraction efficiency or reducing variability. However, the extraction efficiency did not improve when using this accessory, but the procedure did become more efficient. The results from the study indicated that the GTL interface could be employed for the collection of gaseous ATS and incorporated into mobile detection systems for onsite collection and analysis of volatile compounds related to ATS manufacture.

scholarly journals A Miniature Gas Sampling Interface with Open Microfluidic Channels: Characterization of Gas-to-Liquid Extraction Efficiency of Volatile Organic Compounds

Micromachines ◽  
2019 ◽  
Vol 10 (7) ◽  
pp. 486 ◽  
Author(s):  
Andrew C. Warden ◽  
Stephen C. Trowell ◽  
Murat Gel
Keyword(s):  
Extraction Efficiency ◽  
Liquid Extraction ◽  
Capture Efficiency ◽  
Gas Sampling ◽  
Chemosensory Protein ◽  
Detection Systems ◽  
Volatile Organic ◽  
Gas To Liquid ◽  
Sampling Interface

Chemosensory protein based olfactory biosensors are expected to play a significant role in next-generation volatile organic compound (VOC) detection systems due to their ultra-high sensitivity and selectivity. As these biosensors can perform most efficiently in aqueous environments, the detection systems need to incorporate a gas sampling interface for gas-to-liquid extraction. This interface should extract the VOCs from the gas phase with high efficiency and transfer them into the liquid containing biosensors to enable subsequent detection. To design such a transfer interface, an understanding of the key parameters influencing the gas-to-liquid extraction efficiency of target VOCs is crucial. This paper reports a gas sampling interface system based on a microfluidic open-channel device for gas-to-liquid extraction. By using this device as a model platform, the key parameters dictating the VOC extraction efficiency were identified. When loaded with 30 μL of capture liquid, the microfluidic device generates a gas-liquid interface area of 3 cm2 without using an interfacial membrane. The pumpless operation based on capillary flow was demonstrated for capture liquid loading and collection. Gas samples spiked with lipophilic model volatiles (hexanal and allyl methyl sulfide) were used for characterization of the VOC extraction efficiency. Decreasing the sampling temperature to 15 °C had a significant impact on increasing capture efficiency, while variation in the gas sampling flow rate had no significant impact in the range between 40–120 mL min−1. This study found more than a 10-fold increase in capture efficiency by chemical modification of the capture liquid with alpha-cyclodextrin. The highest capture efficiency of 30% was demonstrated with gas samples spiked with hexanal to a concentration of 16 ppm (molar proportion). The approach in this study should be useful for further optimisation of miniaturised gas-to-liquid extraction systems and contribute to the design of chemosensory protein-based VOC detection systems.

scholarly journals A Personalized Machine-Learning-Enabled Method for Efficient Research in Ethnopharmacology. The Case of the Southern Balkans and the Coastal Zone of Asia Minor

2021 ◽  
Vol 11 (13) ◽  
pp. 5826
Author(s):  
Evangelos Axiotis ◽  
Andreas Kontogiannis ◽  
Eleftherios Kalpoutzakis ◽  
George Giannakopoulos
Keyword(s):  
Machine Learning ◽  
Coastal Zone ◽  
Extraction Process ◽  
Asia Minor ◽  
Efficiency And Effectiveness ◽  
Effectiveness And Efficiency ◽  
Intelligent Tools ◽  
Southern Balkans

Ethnopharmacology experts face several challenges when identifying and retrieving documents and resources related to their scientific focus. The volume of sources that need to be monitored, the variety of formats utilized, and the different quality of language use across sources present some of what we call “big data” challenges in the analysis of this data. This study aims to understand if and how experts can be supported effectively through intelligent tools in the task of ethnopharmacological literature research. To this end, we utilize a real case study of ethnopharmacology research aimed at the southern Balkans and the coastal zone of Asia Minor. Thus, we propose a methodology for more efficient research in ethnopharmacology. Our work follows an “expert–apprentice” paradigm in an automatic URL extraction process, through crawling, where the apprentice is a machine learning (ML) algorithm, utilizing a combination of active learning (AL) and reinforcement learning (RL), and the expert is the human researcher. ML-powered research improved the effectiveness and efficiency of the domain expert by 3.1 and 5.14 times, respectively, fetching a total number of 420 relevant ethnopharmacological documents in only 7 h versus an estimated 36 h of human-expert effort. Therefore, utilizing artificial intelligence (AI) tools to support the researcher can boost the efficiency and effectiveness of the identification and retrieval of appropriate documents.

Microwave Assisted Multi-Stage Countercurrent Extraction of Dihydromyricetin from Ampelopsis grossedentataa

2011 ◽  
Vol 7 (4) ◽  
Author(s):  
Wei Li ◽  
Cheng Zheng ◽  
Jian Zhao ◽  
Zhengxiang Ning
Keyword(s):  
Extraction Efficiency ◽  
Extraction Process ◽  
Extraction Time ◽  
Countercurrent Extraction ◽  
Bioactive Substances ◽  
Extraction Solvent ◽  
Microwave Assisted ◽  
Multi Stage ◽  
The Matrix ◽  
Substantial Concentration

A novel microwave assisted multi-stage countercurrent extraction (MAMCE) technique was developed for the extraction of dihydromyricetin from Chinese rattan tea, Ampelopsis grossedentata. The technique combined the advantages of microwave heating and dynamic multi-stage countercurrent extraction and achieved marked improvement in extraction efficiency over microwave assisted batch extraction. Analysis of dihydromyricetin concentrations in the solvent and matrix throughout the extraction process showed that by dividing the extraction into multiple stages and exchanging of solvents between stages, steady and substantial concentration gradients were established between the matrix and solvent, thus enabling the achievement of high extraction efficiency. The yield of dihydromyricetin was significantly affected by temperature, pH, solvent/material ratio and extraction time, and optimal extraction conditions were found to be 80-100°C, at acidic pH with a solvent/material ratio of 25-30 to 1 and extraction time of 5-10 min. With the high extraction efficiency and low usage of extraction solvent, MAMCE could prove to be a promising extraction technique which can be applied to the extraction of dihydromyricentin and other bioactive substances from natural materials.

scholarly journals Tantalum and Niobium Selective Extraction by Alkyl-Acetophenone

Metals ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 654 ◽  
Author(s):  
Moussa Toure ◽  
Guilhem Arrachart ◽  
Jean Duhamet ◽  
Stephane Pellet-Rostaing
Keyword(s):  
Extraction Efficiency ◽  
Methyl Isobutyl Ketone ◽  
Selective Extraction ◽  
Extraction Process ◽  
Liquid Extraction ◽  
Methyl Isobutyl ◽  
Isobutyl Ketone ◽  
Waste Solution ◽  
Liquid Liquid Extraction ◽  
D Values

A study has been carried out on Ta and Nb recovery by a liquid-liquid extraction process using 4-methylacetophenone (4-MAcPh) as the organic phase. The 4-MAcPh was compared to methyl isobutyl ketone (MIBK) with respect to extraction efficiencies (D values) at different concentrations of H2SO4 in the aqueous phase. The results showed a similar extraction of Nb for both solvents. However, for Ta, extraction efficiency is increased by a factor of 1.3 for 4-MAcPh. In addition, the MIBK solubilized completely after 6 mol∙L−1 of H2SO4 against only a loss of 0.14–4% for 4-MAcPh between 6 and 9 mol∙L−1 of H2SO4. The potential of 4-MAcPh has also been studied to selectively recover Ta from a model capacitor waste solution. The results showed a selectivity for Ta in the presence of impurities such as Ag, Fe, Ni and Mn. The 4-MAcPh also presents the advantage of having physicochemical properties adapted to its use in liquid-liquid extraction technologies such as mixer-settlers.

Machine Learning Applications for Classification Emergency and Non-Emergency Patients

2020 ◽  
pp. 104-120
Author(s):  
Zeynel Abidin Çil ◽  
Abdullah Caliskan
Keyword(s):  
Machine Learning ◽  
Emergency Departments ◽  
Emergency Services ◽  
Classification Problems ◽  
Data Set ◽  
Emergency Patients ◽  
Efficiency And Effectiveness ◽  
Machine Learning Applications ◽  
Increase Productivity ◽  
Short Time

Emergency departments of hospitals are busy. In recent years, patient arrivals have significantly risen at emergency departments in Turkey like other countries in the world. The main important features of emergency services are uninterrupted service, providing services in a short time, and priority to emergency patients. However, patients who do not need immediate treatment can sometimes apply to this department due to several reasons like working time and short waiting time. This situation can reduce efficiency and effectiveness at emergency departments. On the other hand, computers solve complex classification problems by using machine learning methods. The methods have a wide range of applications, such as computational biology and computer vision. Therefore, classification of emergency and non-emergency patients is vital to increase productivity of the department. This chapter tries to find the best classifier for detection of emergency patients by utilizing a data set.

scholarly journals A Novel Green Extraction Technique for Extracting Flavonoids from Folium nelumbinis by Changing Osmosis Pressure

Materials ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 4192
Author(s):  
Hai-Yan Fang ◽  
Ying-Qin Wei ◽  
Meng-Li Zhang ◽  
Wei Liu
Keyword(s):  
Extraction Efficiency ◽  
Chemical Potential ◽  
Volume Fraction ◽  
Antioxidant Activities ◽  
Morphological Changes ◽  
Extraction Process ◽  
Extraction Technique ◽  
Salting Out ◽  
Digital Microscope ◽  
Main Factor

A new green and sustainable extraction technique, namely osmosis extraction (OE), was developed for efficient extracting flavonoids from Folium nelumbinis by changing the osmotic pressure. The antioxidant activities of the extracted flavonoids were also evaluated. Ethanol and ammonium sulfate were selected for the OE system because they are environmentally friendly. The maximum flavonoids concentration in the top phase was obtained with an ethanol volume fraction of 42.0% and the salt mass of 1.9 g. The kinetic behavior of the extraction process showed that OE had higher efficiencies especially coupled with ultrasonication due to the accompanying and serious morphological changes of Folium nelumbinis cells observed by digital microscope and nano-computed tomography (nano-CT). Results of morphological and anatomical features showed that the higher intracellular chemical potential made the cell expand and even led to bursting. The results also showed that the extraction efficiency of flavonoids with high antioxidant activities was higher than that of the traditional method. The interface effect enhanced the extraction during the salting-out extraction and osmosis was the main factor that improved the extraction efficiency.

scholarly journals Effectiveness of the mechanical excitation applied to the olive paste: possible improving of the oil yield, in malaxation phase, by vibration systems

2014 ◽  
Vol 44 (4) ◽  
pp. 166 ◽  
Author(s):  
Tullia Gallina Toschi ◽  
Annachiara Berardinelli ◽  
Chiara Cevoli ◽  
Eleonora Iaccheri ◽  
Giuseppe Di Lecce ◽  
...  
Keyword(s):  
Extraction Efficiency ◽  
Oil Quality ◽  
Extraction Process ◽  
Oil Extraction ◽  
Negative Effects ◽  
Mechanical Vibrations ◽  
Resonant Condition ◽  
Electrodynamic Shaker ◽  
Maximum Increment ◽  
Vibration Tests

The mechanical vibrations characterized by a frequency lower than 200 Hz could promote the cells breakage and improve the oil extraction process by avoiding, at the same time, the negative effects on the commercial qualitative parameters due to the use of the heating during malaxation. Vibration tests were conducted by means of an electrodynamic shaker in order to find the optimal frequency levels of excitation, able to put in a resonant condition the olive paste. Sinusoidal accelerations at constant acceleration (120 m/s<sup>2</sup>), in a range between 5 and 200 Hz were explored. The 50 Hz and 80 Hz frequencies were able to put in resonant condition the olive paste. In the vibrated samples at 50 Hz (15 min of treatment), the maximum increment of the extraction efficiency (about 53% in comparison with the control), was observed. Further studies could be conducted in order to assess the synergic effect of the mechanical vibrations and the malaxation on the oil extraction efficiency, with the aim of reducing the time of the whole phase and avoiding changes in the oil quality traits.

scholarly journals Microwave-Assisted Industrial Scale Cannabis Extraction

Technologies ◽  
2020 ◽  
Vol 8 (3) ◽  
pp. 45
Author(s):  
Marilena Radoiu ◽  
Harmandeep Kaur ◽  
Anna Bakowska-Barczak ◽  
Steven Splinter
Keyword(s):  
Continuous Flow ◽  
Extraction Efficiency ◽  
Scale Up ◽  
Extraction Process ◽  
Extraction Methods ◽  
Flowering Plant ◽  
Industrial Scale ◽  
Microwave Assisted ◽  
Operation Conditions ◽  
Assisted Extraction

Cannabis is a flowering plant that has long been used for medicinal, therapeutic, and recreational purposes. Cannabis contains more than 500 different compounds, including a unique class of terpeno-phenolic compounds known as cannabinoids. Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) are the most extensively studied cannabinoids. They have been associated with the therapeutic and medicinal properties of the cannabis plant and also with its popularity as a recreational drug. In this paper, an industrial method for cannabis extraction using 915 MHz microwaves coupled with continuous flow operation is presented. The main advantages of the microwave-assisted extraction (MAE) are associated to the continuous-flow operation at atmospheric pressure which allows for higher volumes of biomass to be processed in less time than existing extraction methods, with improved extraction efficiency leading to increased final product yields, improved extract consistency and quality because the process does not require stopping and restarting material flows, and ease of scale-up to industrial scale without the use of pressurised batch vessels. Moreover, due to the flexibility of changing the operation conditions, MAE eliminates additional steps required in most extraction methods, such as biomass decarboxylation or winterisation, which typically adds at least a half day to the extraction process. Another factor that sets MAE apart is the ability to achieve high extraction efficiency, i.e., up to 95% of the active compounds from cannabis biomass can be recovered at industrial scale.

scholarly journals Pengaruh Tri-n-Oktil Posfin Oksida dan Tingkat Ekstraksi pada Pemurnian Konsentrat Thorium

EKSPLORIUM ◽  
2015 ◽  
Vol 36 (2) ◽  
pp. 109
Author(s):  
M.V. Purwani ◽  
Moch. Setyadji
Keyword(s):  
Organic Phase ◽  
Separation Factor ◽  
Extraction Efficiency ◽  
Phase 1 ◽  
Extraction Process ◽  
Air Stripping ◽  
Total Separation ◽  
Processing Product ◽  
Thorium Oxalate ◽  
Total Extraction

Telah dilakukan ekstraksi konsentrat thorium oksalat hasil olah monasit memakai ekstraktan Tri – n - Oktil Posfin Oksida (TOPO).  Pengotor  yang paling banyak  terkandung dalam konsentrat thorium oksalat adalah cerium (Ce) dan lantanum (La).  Tujuan penelitian ini adalah untuk memurnikan thorium (Th) dengan memisahkan Ce dan La dengan cara ekstraksi. Ekstraksi dilakukan secara batch dan bertingkat.  Larutan umpan atau fase air adalah 10 gram konsentrat Th oksalat yang dilarutkan dalam 10,08 M HNO3 sehingga volume menjadi 100 mL dan fase organik adalah TOPO dalam kerosen.  Stripping setiap tingkat ekstraksi dilakukan tiga kali, yaitu stripping pertama memakai air, stripping kedua memakai asam oksalat 5%, dan stripping ketiga memakai air. Waktu ekstraksi setiap tingkat 15 menit dan waktu stripping setiap tingkat  5 menit dengan perbandingan fase air dengan fase organik adalah 1 berbanding 1.  Parameter yang diteliti  adalah persentase TOPO dalam kerosen dan jumlah tingkat ekstraksi. Pemakaian TOPO dalam kerosen yang optimum 5% dan jumah tingkat ekstraksi 3.  Pada ekstraksi I diperoleh konsentrat Ce dan pada tingkat ekstraksi II dan III diperoleh Th.  Efisiensi ekstraksi Th  tingkat II sebesar 39,76% dan efisiensi ekstraksi Th tingkat III 26,33%. Koefisien distribusi (Kd) Th tingkat ekstraksi II adalah 0,7587 dan Kd Th tingkat ekstraksi III  1,0096. Efisiensi ekstraksi Th total adalah  80,08 %, efisiensi ekstraksi Ce total  56,12%,  efisiensi ekstraksi La total  1,54.  Faktor pisah (FP) Th – Ce pada ekstraksi I adalah 1,00, FP Th – La pada ekstraksi I  92,07, FP Th – Ce pada ekstraksi II adalah 250,24 dan FP Th – La  pada ekstraksi II adalah ∞,  FP Th – Ce pada ekstraksi III 124,22 dan FP Th – La pada ekstraksi III adalah ∞. Faktor pisah total Th – Ce sebesar 1,4270 dan Faktor pisah total Th – La  47,0459. Kadar Th oksalat pada ekstraksi II sebesar 97,06%, kadar Th oksalat pada ekstraksi III  98,00 %. The extraction of thorium oxalate concentrate as processing product  of monazite using  Tri  Octyl Posfine Oxide  (TOPO) has been done.  The most impurities contained in thorium oxalate concentrate are Ce (cerium) and La (lanthanum). The purpose of this study is to purify Th by separating Ce and La using extraction process. The extraction is done by bacth and multistage. The solution of  feed or water phase is 10 grams of Th oxalate concentrate dissolved in 10.08 M HNO3 so that the volume becomes 100 mL and the organic phase is TOPO in kerosene. Stripping in each stage conducted three times, first stripping use water, second stripping use 5 % oxalic acid and the third stripping use water. Extraction time at every stage is 15 minutes and stripping time at every stage is 5 minutes with  ratio of aqueous phase to organic phase = 1 : 1 . The parameters were studied % TOPO - kerosene and number of extraction stage. The optimum usage of TOPO in kerosene is 5 %.  On extraction I obtained Ce concentrate and on extraction II and III obtained Th concentrates. The extraction II efficiency of Th is 39.76 % and extraction III efficiency of Th is 26.33 % . Coefficient of distribution (Kd) of Th in stage II is 0.7587 and Kd of Th in stage III is 1.0096.  Total extraction efficiency of Th is  80.08 %, total extraction efficiency of Ce is 56.12 %,  and total extraction efficiency of La is 1.54 %. The separation factor of  Th – Ce in extraction I  is 1.00 and separation factor of  Th – La in extraction I  is 92.0,  separation factor of  Th – Ce in extraction II  is 250.24, and separation  factor of  Th – La in extraction II  is ∞.  Separation factor of  Th – Ce in extraction III  is 124.22 and separation factor of  Th – La in extraction III  is  ∞.  Total  separation  factor of  Th – Ce  is 1.4270 and total separation factor of  Th – La is 4.0459.  The content of Th oxalate in stripping product from the extraction II is 97.06 % and in stripping product from  the extraction III is 98.00%.

scholarly journals Microwave Extraction vs. Other Techniques for Industrial Scale Cannabis Extraction

2020 ◽  
Author(s):  
Marilena Radoiu ◽  
Harmandeep Kaur ◽  
Anna Bakowska-Barczak ◽  
Steven Splinter
Keyword(s):  
Continuous Flow ◽  
Extraction Efficiency ◽  
Scale Up ◽  
Extraction Process ◽  
Extraction Methods ◽  
Flowering Plant ◽  
Industrial Scale ◽  
Active Compounds ◽  
Operation Conditions ◽  
Assisted Extraction

Cannabis is a flowering plant that has long been used for medicinal, therapeutic, and recreational purposes. Cannabis contains more than 500 different compounds, including a unique class of terpeno-phenolic compounds known as cannabinoids; &Delta;9-tetrahydrocannabinol (THC) and cannabidiol (CBD) are the most prevalent cannabinoids and have been associated with the therapeutic and medicinal properties of the cannabis plant. In this paper, continuous flow microwave assisted extraction (MAE) is presented and compared with other methods for commercial cannabis extraction. The practical issues of each extraction method are discussed. The main advantages of MAE are: continuous-flow method which allows for higher volumes of biomass to be processed in less time than existing extraction methods, improved extraction efficiency leading to increased final product yields, improved extract consistency and quality because the process does not require stopping and restarting material flows, and ease of scale-up to industrial scale without the use of pressurised batch vessels. Moreover, due to the flexibility of changing the operation conditions, MAE eliminates additional steps required in most extraction methods, such as biomass decarboxylation, winterisation, which typically adds at least a half day to the extraction process. Another factor that sets MAE apart is the ability to achieve high extraction efficiency even at the industrial scale. Whereas the typical recovery of active compounds using supercritical CO&not;2 remains around 70-80%, via MAE up to 95% of the active compounds from cannabis biomass can be recovered at the industrial scale.

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