scholarly journals Estimation of ethylene production and 1-aminocyclopropane-1-carboxylic acid in plants by means of gas chromatography

2008 ◽  
Vol 54 (No. 2) ◽  
pp. 55-60 ◽  
Author(s):  
H. Fišerová ◽  
Z. Mikušová ◽  
M. Klemš
Keyword(s):  
Gas Chromatography ◽  
Carboxylic Acid ◽  
Ethylene Production ◽  
Sampling Procedure ◽  
Alternative Methods ◽  
Time Consumption ◽  
Advantages And Disadvantages ◽  
Endogenous Level ◽  
Extraction And Purification ◽  
And Storage

The paper deals with problems associated with preparation and collection of samples when estimating the production of ethylene and content of ACC (1-aminocyclopropane-1-carboxylic acid) in plants by means of gas chromatography. A proper method of sampling can significantly influence not only the reliability of obtained data but also their interpretation. Attention was paid to cultivation of plant material, sampling vessels, conditions of ethylene production, sampling procedure, and storage of gaseous samples. The estimation of ACC as a precursor of ethylene is more laborious but it supplements the information about the endogenous level of ethylene in a given part of the plant organism. The authors describe the sampling procedure, methods of sample preservation, extraction and purification, and also the method of oxidation of ACC to ethylene. In the final part of this study the authors evaluate the time consumption and difficulty of individual methods and describe their advantages and disadvantages as compared with other, alternative methods.

scholarly journals Review on stationary phases and coating methods of MEMs gas chromatography columns

2020 ◽  
Vol 39 (1) ◽  
pp. 247-259
Author(s):  
Liu Yang ◽  
Molin Qin ◽  
Junchao Yang ◽  
Genwei Zhang ◽  
Jiana Wei
Keyword(s):  
Gas Chromatography ◽  
Microelectromechanical Systems ◽  
Stationary Phases ◽  
Preparation Methods ◽  
Site Analysis ◽  
Advantages And Disadvantages ◽  
Coating Methods ◽  
On Line ◽  
Inorganic Adsorbents ◽  
Gas Chromatography Columns

Abstract Gas chromatography (GC) is an important and widely used technique for separation and analysis in the field of analytical chemistry. Micro gas chromatography has been developed in response to the requirement for on-line analysis and on-site analysis. At the core of micro gas chromatography, microelectromechanical systems (MEMs) have the advantages of small size and low power consumption. This article introduces the stationary phases of micro columns in recent years, including polymer, carbon materials, silica, gold nanoparticles, inorganic adsorbents and ionic liquids. Preparation techniques ranging from classical coating to unusual sputtering of stationary phases are reviewed. The advantages and disadvantages of different preparation methods are analyzed. The paper introduces the separation characteristics and application progress of MEMs columns and discusses possible developments.

Approaches to motion control intellectualization of a mobile robot

2021 ◽  
Author(s):  
Stepan A. Lapshinov ◽  
Vadim A. Shakhnov ◽  
Anton V. Yudin
Keyword(s):  
Mobile Robot ◽  
Motion Control ◽  
Control Device ◽  
Alternative Methods ◽  
Design Solution ◽  
Movement Direction ◽  
Software Complex ◽  
Advantages And Disadvantages ◽  
Drive Control ◽  
Omni Wheel

The paper considers the principles of intelligent motion control of mobile robots using the example of omni-wheel modules. The proposed design solution uses components of movement intelligence in any direction, receiving commands from a human operator or above a standing automatic control device, consisting of an angle of movement direction and the required distance of movement. This paper presents an embodiment of using omni-wheels to move a mobile robot over a flat surface. Features of device and application of drive with three omni-wheels in comparison with differential drive are considered. Kinematics, basic principles of motion control formation, hardware and software complex for its implementation are described. There were revealed two alternative methods of organization of drive control in conditions of shortage of low-level hardware resources on the basis of 8-bit microcontroller, their advantages and disadvantages have been analyzed. Process support and materials have been presented that allows realizing the competitive advantages of development while minimizing the cost of components. Features of mobile robot travel route development have been mentioned on the example of competitive practice.

of storage as short as possible, only; 24 h should not be ex­ ceeded. Table III comprises the most important criteria for valid static and dynamic sampling. It seems that both the guide of Warren Springs, U.K. and the VDI-Guideline might be a useful base to describe commonly accepted sampling procedures aiming at a standardization of sampling which might be a first step for a harmonization of olfactometric measurements in the different laboratories and countri es. REFERENCES (1) BULLEY, N.R. and D. PHILLIPS (1980). Sensory evaluation of agricul­ tural odours: A critical review. Can. Agric. Eng. 22, 107 - 112. (2) HENRY, J.G. and R. GEHR (1980). Odour control: An operator's guide. Journal WPCF 52, 2523 - 2537. (3) ROOS, C., J.A. DON and J. SCHAEFER (1984). Characterization of odour-polluted air. In: Proc.Int.Symp., Soc. Beige de Filtr. (eds.), 25-27 April 1984, Louvain-La-Neuve, Belgium, pp. 3 - 22. (4) BAKER, A.R. and R.C. DOERR (1959). Methods of sampling and storage of air containing vapors and gases. Int.J.Air Poll. 2, 142 - 158. (5) SCHUETTE, F.J. (1967). Plastic bags for collection of gas samples. Atmosph.Environm. 1, 515 - 519. (6) SCHODDER, F. (1977T. Messen von Geruchsstoffkonzentrationen, Erfassen von Geruch. Grundl. Landtechnik 27, 73 - 82. (7) CORMACK, D., T.A. DORLING and B.W7J. LYNCH (1974). Comparison of tech­ niques for organoleptic odour-intensity assessment. Chem.Ind. (Lon­ don) no. 2, 857 - 861. (8) SCHUETZLE, D., T.J. PRATER and S. RUDDELL (1975). Sampling and anal­ ysis of emissions from stationary sources. I. Odour and total hydro­ carbons. APCA Journal 25, 925 - 932. (9) WAUTERS, E., E. WALRAVENS, E. MUYLLE and G. VERDUYN (1983). An evalu­ ation of a fast sampling procedure for the trace analysis of volatile organic compounds in ambient air. Environm.Monitor.Assessm. 3, 151-160. (10) LACHENMAYER, U. and H. KOHLER (1984). Untersuchungen zur Neuentwick-lung eines Olfaktometers. Staub - Reinhalt. Luft 44, 359 - 362. (11) BERNARD, F. (1984). Simplified methods of odour measurement: Indus­ trial application and interest for administrative control. Proc. Int. Symp., Soc. Beige de Filtr. (eds.), 25 - 27 April 1984, Louvain-La-Neuve, Belgium, pp. 139 - 150. (12) GILLARD, F. (1984). Measurement of odours by dynamic olfactometry. Application to the steel and carbonization industries. Proc.Int.Symp., Soc. Beige de Filtr. (eds.), 25 - 27 April 1984, Louvain-La-Neuve, Belgium, pp. 53 - 86. (13) MANNEBECK, H. (1975). Tragbare Olfaktometer. VDI-Bericht 226, 103-105. (14) BEDBOROUGH, D.R. (1980). Sensory measurement of odours. In: Odour Control - a concise guide, F.H.H. Valentin and A.A. North (eds.), Warren Springs Laboratories, Stevenage, Hertfordshire, U.K., pp. 17-30. (15) THIELE, V. (1984). Olfaktometrie an einer Emissionsquelle - Ergebnis-se des VDI-Ringvergleichs. Staub - Reinhalt. Luft 44, 342 - 351. (16) DUFFEE, R.A., J.P. WAHL, W. MARRONE and J.S. NADERT1973). Defining and measuring objectionable odors. Internat. Pollution Eng. Congress, Philadelphia, paper no 25a, pp. 192 - 201.

1986 ◽  
pp. 62-62
Keyword(s):  
Ambient Air ◽  
Sampling Procedure ◽  
Plastic Bags ◽  
Volatile Organic ◽  
Odour Control ◽  
Sampling Procedures ◽  
Dynamic Sampling ◽  
Concise Guide ◽  
And Storage

scholarly journals IDENTIFICATION OF BIOACTIVE COMPOUNDS BY GAS CHROMATOGRAPHY-MASS SPECTROMETRY ANALYSIS OF SYZYGIUM JAMBOS (L.) COLLECTED FROM WESTERN GHATS REGION COIMBATORE, TAMIL NADU

2016 ◽  
Vol 10 (1) ◽  
pp. 364 ◽  
Author(s):  
Devakumar Devakumar Joseph ◽  
Keerthana Veerasamy ◽  
Sudha Siva Singaram
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Carboxylic Acid ◽  
Bioactive Compounds ◽  
Leaf Extract ◽  
Mass Spectrometry Analysis ◽  
Gas Chromatography Mass Spectrometry ◽  
Spectrometry Analysis ◽  
Syzygium Jambos ◽  
Chromatography Mass Spectrometry

ABSTRACTObjective: The aim of this study was to investigate the presence of bioactive compounds in the methanolic leaf extract of Syzygium jambos.Methods: Collected leaves were shade dried and made into fine powder, extracted with methanol, and the methanolic extract was prepared andanalyzed for the presence of bioactive compounds by gas chromatography-mass spectrometry (GC-MS). The mass spectrum of the chromatographywas matched with NIST and WILEY Libraries.Results: The GC-MS analysis revealed the presence of 45 active compounds in the extract. From the GC-MS investigation, 1-Deoxy-d-mannitol3-methyl-2-methylsulfanyl-5-nitro-6-pyridin-4-ylpyrimidin-4-one, 3-Pentadecylphenol, 2-biphenylene carboxylic acid, Quinoline-3-carboxylic acid,and Stigmast-5-en-3-ol are important phytoconstituents which have antipyretic and antiparasitic activities.Conclusion: The present investigation revealed preliminary information on phytocompounds presented in S. jambos leaf extract which is very usefulfor the human community.Keywords: Syzygium jambos, Gas chromatography-mass spectrometry analysis, 1-Deoxy-d-mannitol, Phytoconstituents, Methanolic leaf extract.

scholarly journals Modern concepts of conversion and storage of energy by dispersed materials absorption

2002 ◽  
Vol 34 (3) ◽  
pp. 247-259
Author(s):  
Dragica Minic-Popovic ◽  
M.V. Susic
Keyword(s):  
Research And Development ◽  
Metal Hydride ◽  
Development Stage ◽  
Ease Of Use ◽  
Glass Microsphere ◽  
Carbon Clusters ◽  
Storage Method ◽  
Advantages And Disadvantages ◽  
Storage Methods ◽  
And Storage

Once hydrogen is generated, the question asked: How do we store hydrogen? Hydrogen can be stored in a variety of ways, each with specific advantages and disadvantages. The overall criteria for choosing a storage method should be safety and ease of use. Described in this paper and listed below are different storage methods available today (compressed hydrogen, liquid carrier storage, glass microsphere, chemically stored hydrogen) in addition to some techniques that are still in the research and development stage: power balls, metal hydride tanks and carbon clusters.

scholarly journals COMPARATIVE ANALYSIS OF COMPACT METHODS REPRESENTATIONS OF GRAPHIC INFORMATION

2021 ◽  
Vol 1 (37) ◽  
pp. 130-143
Author(s):  
O. Gertsiy
Keyword(s):  
Comparative Analysis ◽  
Communication Systems ◽  
Video Data ◽  
Transport Infrastructure ◽  
Practical Significance ◽  
Jpeg 2000 ◽  
Advantages And Disadvantages ◽  
Graphic Information ◽  
The Cost ◽  
And Storage

The main characteristics of graphic information compression methods with losses and without losses (RLE, LZW, Huffman's method, DEFLATE, JBIG, JPEG, JPEG 2000, Lossless JPEG, fractal and Wawelet) are analyzed in the article. Effective transmission and storage of images in railway communication systems is an important task now. Because large images require large storage resources. This task has become very important in recent years, as the problems of information transmission by telecommunication channels of the transport infrastructure have become urgent. There is also a great need for video conferencing, where the task is to effectively compress video data - because the greater the amount of data, the greater the cost of transmitting information, respectively. Therefore, the use of image compression methods that reduce the file size is the solution to this task. The study highlights the advantages and disadvantages of compression methods. The comparative analysis the basic possibilities of compression methods of graphic information is carried out. The relevance lies in the efficient transfer and storage of graphical information, as big data requires large resources for storage. The practical significance lies in solving the problem of effectively reducing the data size by applying known compression methods.

scholarly journals Opportunities and Questions: A Short Report on Rubric Assessments in Asia and the Middle East

2019 ◽  
Author(s):  
Ronnie Goodwin
Keyword(s):  
Middle East ◽  
Assessment Tool ◽  
Relevant Literature ◽  
Alternative Methods ◽  
Learning Theories ◽  
Short Report ◽  
Rating Systems ◽  
Self Assessment ◽  
Advantages And Disadvantages ◽  
The Impact

This qualitative short report considers the viability of the use of rubrics or alternative methods to assess writing in Asia and the Middle East. The background of learning theories, assessment types, and self-assessment literature provides a foundation for further discussion of the appropriate use of rubrics, including the prioritization of criterion, the quality of scoring, the impact of organizational features on scoring, the influence of bias, and the best application of rubric assessment. Relevant points for further study are identified, such as differentiation in research between generalized analytical rating systems and rubric assessment with specific, empirical criterion. The contradictory research regarding the advantages and disadvantages of rubric assessment in comparison with holistic assessment are of particular and crucial interest for global pedagogy. Many of the reviewed Western articles excluded Asian perspectives- except for China- and thus present a limited understanding of social and educational compatibility with new assessments and rubric assessments in particular. The discussion identifies patterns and points of contention and seeks to explore viewpoints rather than limit the scope of inquiry and consideration thus noting that relevant literature suggests that with appropriate teacher training, teachers may appropriately use rubrics as a formative assessment tool for writing in Asia and the Middle East.

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