scholarly journals Comparison of Methods for Extraction of Tobacco Alkaloids

2001 ◽  
Vol 84 (2) ◽  
pp. 309-316 ◽  
Author(s):  
Nadiá M Jones ◽  
M Gabriela Bernardo-Gil ◽  
M Graço Lourenco
Keyword(s):  
Ultrasonic Method ◽  
Extraction Methods ◽  
International Standards ◽  
Low Level ◽  
Aoac Method ◽  
Tobacco Alkaloids ◽  
Microwave Techniques ◽  
High Level ◽  
International Standards Organization ◽  
Solvent Volume

Abstract Ultrasound and microwave techniques were used to extract tobacco alkaloids, and response surface methodology was used to optimize extraction conditions. Ultrasonic technique factors were temperature, 30–85°C; time, 3–45 min; solvent volume, 8–80 mL. Microwave extraction factors were pressure, 15–75 psi; time, 3–40 min; power, 30–90% of the maximum magnetron power of 650 W. Soxhlet and solvent AOAC-modified extraction methods were also applied after some improvements. Nicotine, nornicotine, anabasine, and anatabine were quantified by gas chromatography. A steam distillation International Standards Organization method for total alkaloid evaluation was used as reference. The results obtained by the different methods were compared using a least squares deviation test. The ultrasonic and the proposed modified-AOAC extraction method were the more convenient with regard to practicability and precision. The relative deviations (n = 5) were as follows: For the ultrasonic method in low-level alkaloid tobaccos, 0.7% nicotine and 1.4–14% minor alkaloids; in high-level alkaloid tobaccos, 2.4% nicotine and 4.5–5.1% minor alkaloids. For the modified AOAC method in low-level alkaloid tobaccos, 0.9% nicotine and 2.4–11.6% minor alkaloids; and in high-level alkaloid tobaccos, 1.7% nicotine and 2.0–2.4% minor alkaloids.

Modification of the Rapid Screening Method for Aflatoxin in Corn for Quantitative Use

1985 ◽  
Vol 68 (3) ◽  
pp. 453-456
Author(s):  
Joseph R Spilmann
Keyword(s):  
Quantitative Method ◽  
Screening Method ◽  
Rapid Screening ◽  
Low Level ◽  
Modified Method ◽  
Corn Products ◽  
Aoac Method ◽  
Rapid Screening Method ◽  
High Level

Abstract A study was made to determine if the official AOAC method for screening of aflatoxin in corn could be modified for use as a quantitative method. Several different corn products were analyzed using the modified method, with an average savings of over 1 h/sample vs the CB method. Average recoveries for aflatoxin Bt were 94% for the low level spiked samples and 108% for the high level. Samples of corn and corn products containing naturally incurred aflatoxin were also analyzed with the modified method, and the results compared favorably with those obtained by the CB method.

scholarly journals Measurement and Analysis of Vibration Levels for Truck Transport Environment in Korea

2020 ◽  
Vol 10 (19) ◽  
pp. 6754 ◽  
Author(s):  
Jongmin Park ◽  
Sangil Choi ◽  
Hyun Mo Jung
Keyword(s):  
Travel Speed ◽  
International Standards ◽  
Statistical Characteristics ◽  
Leaf Spring ◽  
Low Level ◽  
Simulation Protocol ◽  
Truck Transport ◽  
Heavy Tailed ◽  
The Right ◽  
High Level

The first step in the appropriate packaging design of food, agricultural and industrial products is to conduct an accurate simulation of the vehicle transport environment, in which a power spectral density (PSD) profile is applied. Although several researchers have mentioned the limitations of PSD-based simulation, it is still widely used because accelerated test conditions can be easily generated from the PSD acquired from a particular transport section. In this study, three representative trucks and transport test routes of domestic freight transport were selected to develop a simulation protocol for a truck transport environment in Korea. These studies are needed to compare domestic transport vibration levels with those presented by the International Standards (ASTM: West Conshohocken, USA, ISTA: Chicago, USA) and to simulate damage to packaged products by domestic transport environments. The composite PSD profile for the truck transport environment was established by dividing it into high-and low-level composite PSD profiles representing the top 30% and lower 70%, respectively, of the measured vibration events based on the root-mean-square acceleration (rms G) of the measured vibration events. Also, the effects of these variables on the truck vibration level were analyzed by extracting data corresponding to the truck’s pre-planned travel speed and road conditions in the vibration records measured on the test route. Moreover, kurtosis, skewness, and normal quantile-quantity (Q-Q) analyses were conducted to understand the statistical characteristics of Korea’s truck transport environment. Statistical analysis showed that the measured vibration events had a heavy-tailed distribution and skewed to the right, causing dissymmetry. The overall rms G of the developed high-level and low-level composite PSD profiles in the range from 1 to 250 Hz were 0.47 and 0.32 for leaf-spring trucks and 0.30 and 0.14 for air-ride trucks, respectively.

Comparison of AOAC and EEC Methods for Determining Available P2O5 in Fertilizer

1984 ◽  
Vol 67 (3) ◽  
pp. 594-596
Author(s):  
Frank J Johnson ◽  
Kenneth L Parks
Keyword(s):  
European Economic Community ◽  
Initial Study ◽  
International Standards ◽  
Ammonium Citrate ◽  
Triple Superphosphate ◽  
Final Study ◽  
Interlaboratory Studies ◽  
Aoac Method ◽  
The Difference ◽  
International Standards Organization

Abstract Three interlaboratory studies are described in which AOAC method 2.053 was compared with the neutral ammonium citrate method for direct available P2O5 recommended by the European Economic Community (EEC). The initial study comprised 5 laboratories and 7 samples. Significantly more available P205 was found by the AOAC method in 5 of 7 samples tested. Fifteen laboratories analyzed 8 samples in the second study; only 2 samples yielded more P2O5 by the AOAC method. The final study included 9 samples and 14 laboratories. Results for the AOAC method were higher on 4 samples. Conclusions reached from the 3 studies are (1) The AOAC method gave consistently higher values for available P2O5, especially for triple superphosphate samples; and (2) the difference between methods increased with increasing amounts of citrate-insoluble P2O5. All data were reported to the International Standards Organization Working Group on phosphorus in fertilizer.

scholarly journals Extraction Methods for Recovery of Volatile Organic Compounds from Fortified Dry Soils

1996 ◽  
Vol 79 (5) ◽  
pp. 1198-1204 ◽  
Author(s):  
Marti M Minnich ◽  
John H Zimmerman ◽  
Brian A Schumacher
Keyword(s):  
Volatile Organic Compounds ◽  
Organic Carbon ◽  
Organic Compounds ◽  
Methanol Extract ◽  
Extraction Methods ◽  
Low Level ◽  
Methanol Treatment ◽  
Volatile Organic ◽  
High Level ◽  
Treatment Order

Abstract Recovery of 8 volatile organic compounds (VOCs) from dry soils, each fortified at 800 ng/g soil, was studied in relation to the extraction method and time of extraction. Extraction procedures studied on 2 desiccator-dried soils were modifications of EPA low- and high-level purge-and-trap extractions (SW-846 Method 5030A): treatment 1, unmodified low-level procedure; treatment 2,18 h water presoak followed by low-level procedure; treatment 3, 24 h methanol extract at room temperature followed by high-level procedure; and treatment 4, 24 h methanol extract at 65°C followed by highlevel procedure. VOC recoveries from replicate soil samples increased in the treatment order 1 through 4. With Charleston soil (8% clay and 3.8% organic carbon), highly significant differences (p ≤ 0.001) in recoveries among treatments were observed for trichloroethene (TCE), tetrachloroethene (PCE), toluene, ethylbenzene, and o-xylene, with 2- to 3- fold increased recoveries between treatments 1 and 3. With Hayesville soil (32% clay and 0.2% organic carbon), significant improvements (p ≤ 0.05) in recoveries of toluene, ethylbenzene, o-xylene, 1,1,1-trichloroethane, TCE, and PCE were observed for heated methanol (treatment 4) rather than water extraction (treatment 1), but the increases were less than 2-fold.

Teknik Data Mining Dalam Clustering Produksi Susu Segar Di Indonesia Dengan Algoritma K-Means

2019 ◽  
Vol 1 (1) ◽  
pp. 31-39
Author(s):  
Ilham Safitra Damanik ◽  
Sundari Retno Andani ◽  
Dedi Sehendro
Keyword(s):  
Data Mining ◽  
Milk Production ◽  
Clustering Algorithm ◽  
Clustering Method ◽  
Data Mining Techniques ◽  
Low Level ◽  
Fresh Milk ◽  
Nutritional Needs ◽  
High Level ◽  
Level Cluster

Milk is an important intake to meet nutritional needs. Both consumed by children, and adults. Indonesia has many producers of fresh milk, but it is not sufficient for national milk needs. Data mining is a science in the field of computers that is widely used in research. one of the data mining techniques is Clustering. Clustering is a method by grouping data. The Clustering method will be more optimal if you use a lot of data. Data to be used are provincial data in Indonesia from 2000 to 2017 obtained from the Central Statistics Agency. The results of this study are in Clusters based on 2 milk-producing groups, namely high-dairy producers and low-milk producing regions. From 27 data on fresh milk production in Indonesia, two high-level provinces can be obtained, namely: West Java and East Java. And 25 others were added in 7 provinces which did not follow the calculation of the K-Means Clustering Algorithm, including in the low level cluster.

Determinants of Abuse of the Bodies of the Dead

2019 ◽  
pp. 71-77
Author(s):  
Margarita Khomyakova
Keyword(s):  
Low Income ◽  
Criminal Code ◽  
Value Judgments ◽  
Legal Norms ◽  
Low Level ◽  
Medical Institutions ◽  
Specific Object ◽  
The Subject ◽  
The Dead ◽  
High Level

The author analyzes definitions of the concepts of determinants of crime given by various scientists and offers her definition. In this study, determinants of crime are understood as a set of its causes, the circumstances that contribute committing them, as well as the dynamics of crime. It is noted that the Russian legislator in Article 244 of the Criminal Code defines the object of this criminal assault as public morality. Despite the use of evaluative concepts both in the disposition of this norm and in determining the specific object of a given crime, the position of criminologists is unequivocal: crimes of this kind are immoral and are in irreconcilable conflict with generally accepted moral and legal norms. In the paper, some views are considered with regard to making value judgments which could hardly apply to legal norms. According to the author, the reasons for abuse of the bodies of the dead include economic problems of the subject of a crime, a low level of culture and legal awareness; this list is not exhaustive. The main circumstances that contribute committing abuse of the bodies of the dead and their burial places are the following: low income and unemployment, low level of criminological prevention, poor maintenance and protection of medical institutions and cemeteries due to underperformance of state and municipal bodies. The list of circumstances is also open-ended. Due to some factors, including a high level of latency, it is not possible to reflect the dynamics of such crimes objectively. At the same time, identification of the determinants of abuse of the bodies of the dead will reduce the number of such crimes.

scholarly journals EXPRESS: Marketers Project Their Personal Preferences onto Consumers: Overcoming the Threat of Egocentric Decision Making

2021 ◽  
pp. 002224372199837
Author(s):  
Walter Herzog ◽  
Johannes D. Hattula ◽  
Darren W. Dahl
Keyword(s):  
Decision Making ◽  
Consumer Preferences ◽  
Research Question ◽  
Pilot Studies ◽  
Low Level ◽  
Marketing Managers ◽  
False Consensus Effect ◽  
False Consensus ◽  
High Level

This research explores how marketing managers can avoid the so-called false consensus effect—the egocentric tendency to project personal preferences onto consumers. Two pilot studies were conducted to provide evidence for the managerial importance of this research question and to explore how marketing managers attempt to avoid false consensus effects in practice. The results suggest that the debiasing tactic most frequently used by marketers is to suppress their personal preferences when predicting consumer preferences. Four subsequent studies show that, ironically, this debiasing tactic can backfire and increase managers’ susceptibility to the false consensus effect. Specifically, the results suggest that these backfire effects are most likely to occur for managers with a low level of preference certainty. In contrast, the results imply that preference suppression does not backfire but instead decreases false consensus effects for managers with a high level of preference certainty. Finally, the studies explore the mechanism behind these results and show how managers can ultimately avoid false consensus effects—regardless of their level of preference certainty and without risking backfire effects.

Exploring The Effect of Visual Information Degradation on Human Perception and Performance In A Human-Telerobot System

2020 ◽  
Vol 64 (1) ◽  
pp. 1302-1307
Author(s):  
Richard Stone ◽  
Minglu Wang ◽  
Thomas Schnieders ◽  
Esraa Abdelall
Keyword(s):  
Visual Information ◽  
Human Perception ◽  
Low Level ◽  
Hit Rate ◽  
Word Level ◽  
Level Of Automation ◽  
Significant Difference ◽  
Human Operators ◽  
And Performance ◽  
High Level

Human-robotic interaction system are increasingly becoming integrated into industrial, commercial and emergency service agencies. It is critical that human operators understand and trust automation when these systems support and even make important decisions. The following study focused on human-in-loop telerobotic system performing a reconnaissance operation. Twenty-four subjects were divided into groups based on level of automation (Low-Level Automation (LLA), and High-Level Automation (HLA)). Results indicated a significant difference between low and high word level of control in hit rate when permanent error occurred. In the LLA group, the type of error had a significant effect on the hit rate. In general, the high level of automation was better than the low level of automation, especially if it was more reliable, suggesting that subjects in the HLA group could rely on the automatic implementation to perform the task more effectively and more accurately.

scholarly journals The high-level benefits of low-level sandboxing

2020 ◽  
Vol 4 (POPL) ◽  
pp. 1-32 ◽  
Author(s):  
Michael Sammler ◽  
Deepak Garg ◽  
Derek Dreyer ◽  
Tadeusz Litak
Keyword(s):  
Low Level ◽  
High Level
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