Hydrodynamic Characteristics of Wings in Circular Motion

2002 ◽  
Vol 46 (02) ◽  
pp. 92-98
Author(s):  
Zelik Segal
Keyword(s):  
Experimental Investigation ◽  
Circular Motion ◽  
Hydrodynamic Characteristics ◽  
Large Curvature ◽  
Small Curvature ◽  
Wide Range ◽  
Correct Determination ◽  
Order Of Magnitude ◽  
Wing Chord

Hydrodynamic characteristics of wings in circular motion are determined at present very approximately, as a rule, according to the solution of the problem on streamlining the wing by a small curvature nonviscid potential. However, in some practical cases the radius of the wing trajectory is of the same order of magnitude as the wing chord. That is why there is a necessity for a more correct determination of wing hydrodynamic characteristics, accounting for the relatively large curvature of the wing trajectory and the and viscosity. This paper presents a description and results of our theoretical and experimental investigation of the hydrodynamic characteristics of wings in a wide range of relative radiuses of their motion.

scholarly journals Immobilized Luminescent Bacteria for the Detection of Mycotoxins under Discrete and Flow-Through Conditions

Biosensors ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 63 ◽  
Author(s):  
Olga Senko ◽  
Nikolay Stepanov ◽  
Olga Maslova ◽  
Rashid Akhundov ◽  
Anvar Ismailov ◽  
...  
Keyword(s):  
Aqueous Media ◽  
Photobacterium Phosphoreum ◽  
Poly Vinyl Alcohol ◽  
Bacterial Cells ◽  
Flow Conditions ◽  
Luminescent Bacteria ◽  
Wide Range ◽  
Order Of Magnitude ◽  
Flow Through

A biosensitive element in the form of bacterial Photobacterium phosphoreum cells immobilized in poly(vinyl alcohol) cryogel was tested for the determination of different mycotoxins under discrete and flow-through analysis conditions. The immobilized bioluminescent cells made it possible to quantify the presence of Ochratoxin A, Sterigmatocystin, Zearalenone, and Deoxynivalenon in aqueous media in a wide range of their concentrations (0.017–56 mg/L, 0.010–33 mg/L, 0.009–14 mg/L, and 0.026–177 mg/L, respectively) via measuring the quenching of cell luminescence. The flow conditions allowed the analysis sensitivity to be improved by an order of magnitude in terms of detected concentrations. Using the immobilized luminescent bacterial cells, we have shown the possibility of evaluating the efficiency of the mycotoxins’ hydrolysis under the action of enzymes. In this way, a 94 ± 4.5% efficiency of Zearalenone hydrolysis with hexahistidine-containing organophosphorus hydrolase for 1h-long treatment of the mycotoxin solution (100 mg/L) was shown.

Analysis of Multi-Component Gas Mixtures by Correlation of Infrared Spectra

1984 ◽  
Vol 38 (5) ◽  
pp. 705-709 ◽  
Author(s):  
D Bingham ◽  
C. H. Burton
Keyword(s):  
Experimental Investigation ◽  
Infrared Spectra ◽  
Simulation Study ◽  
Gas Mixtures ◽  
Resolving Power ◽  
Polar Component ◽  
Partial Pressures ◽  
Wide Range ◽  
Gas Pressures

A simulation study and an experimental investigation of the effect of noise and resolution in the determination of polar gas pressures in gas mixtures has been performed The pressures were obtained by a procedure which correlates the polar gas infrared spectra and describes band absorptance phenomenologically For single-polar-component binary mixtures, the partial pressure may be found accurately over a wide range of resolution Low resolving powers are favored with noisy spectra Polar gas partial pressures were also extracted from quaternary mixtures, with an uncertaintity of less than 5% over a wide range of resolving power Improvements to and limitations of the technique are discussed

Effect of aggr egation of initial nanofi ller on reinforcement degree of polypropylene/globular nanocarbon nanocomposites

2020 ◽  
pp. 380-384
Author(s):  
Gas.M. Magomedov ◽  
Gus.M. Magomedov ◽  
I.V. Dolbin
Keyword(s):  
Fractal Dimension ◽  
Specific Surface ◽  
Polymer Matrix ◽  
Interfacial Adhesion ◽  
Filling Degree ◽  
Scaling Model ◽  
Correct Determination ◽  
Order Of Magnitude ◽  
Micromechanical Models

In the framework of dispersive theory of strength, the effect of aggregation of initial disperse nanofiller particles on reinforcement degree is studied on the example of nanocomposites polypropylene/globular nanocarbon. It is shown that increase in aggregation degree of the indicated particles results to essential (approximately in order of magnitude) reduction of specific surface of nanofiller. The corresponding reduction is also observed for fractal dimension of nanofiller aggregates surface, which negatively affect on level of interfacial adhesion nanofiller—polymer matrix. Introduction of reduced filling degree within the framework of scaling model of reinforcement shown that this parameter can be used successively for correct determination of reinforcement degree of nanocomposites using micromechanical models. Thus, the reduced filling degree takes into consideration effects of nanofiller aggregation.

Oospore variation in Nitella gracilis and Nitella mucronata (Charales, Charophyceae) from Poland

Biologia ◽  
2009 ◽  
Vol 64 (2) ◽  
Author(s):  
Jacek Urbaniak
Keyword(s):  
Main Axis ◽  
Scanning Microscopy ◽  
Taxonomic Significance ◽  
Detailed Report ◽  
Interspecific Variations ◽  
Wide Range ◽  
Correct Determination ◽  
Vegetative Characters ◽  
Range Of Variation

AbstractThe determination of the members of Charales (Charophyceae) is not easy. The main reason of this is a wide range of variation in vegetative characters within most of the species. Many features such as the extent of branchlet cortication, the degree of incrustation, length and number of bract cells, spine cells, stipulodes, diameter of the main axis and oospore size and color do not have universal taxonomic significance. In similar, many Nitella species characters such as: general habitus, branchlets and presence of the top segment (mucro), are helpful in determination, however they are often not developed. In this case, the features of oospore wall ornamentation revealed by light and scanning microscopy can be important taxonomic characters of the Charales. The present study shows interspecific variations of the oospore in two Nitella species from Poland which can be helpful in correct determination of both species. Some of the oospore features like number of striae and fossa width can not be used, as they appeared statistically unimportant, and cannot be used in distinguishing between both species. The presented results are the first detailed report of oospore wall ornamentation pattern from Poland for the species studied. Oospore features are presented in detail on the background of some additional tips and among them particularly: length and width of the oospore, ISI idex, width of fossa, width of striae and number of striae.

Development of a method for multielemental determination in water by EDXRF with radioisotopic source of 238Pu.

2019 ◽  
Vol 7 (2A) ◽  
Author(s):  
Camilo Fuentes Serrano ◽  
Juan Reinaldo Estevez Alvares ◽  
Alfredo Montero Alvarez ◽  
Ivan Pupo Gonzales ◽  
Zahily Herrero Fernandez ◽  
...  
Keyword(s):  
Thin Layer ◽  
Expanded Uncertainty ◽  
Considerable Decrease ◽  
X Ray ◽  
Precipitation Efficiency ◽  
Method Of Determination ◽  
Sensitivity Curves ◽  
Order Of Magnitude ◽  
Metrological Parameters

A method for determination of Cr, Fe, Co, Ni, Cu, Zn, Hg and Pb in waters by Energy Dispersive X Ray Fluorescence (EDXRF) was implemented, using a radioisotopic source of 238Pu. For previous concentration was employed a procedure including a coprecipitation step with ammonium pyrrolidinedithiocarbamate (APDC) as quelant agent, the separation of the phases by filtration, the measurement of filter by EDXRF and quantification by a thin layer absolute method. Sensitivity curves for K and L lines were obtained respectively. The sensitivity for most elements was greater by an order of magnitude in the case of measurement with a source of 238Pu instead of 109Cd, which means a considerable decrease in measurement times. The influence of the concentration in the precipitation efficiency was evaluated for each element. In all cases the recoveries are close to 100%, for this reason it can be affirmed that the method of determination of the studied elements is quantitative. Metrological parameters of the method such as trueness, precision, detection limit and uncertainty were calculated. A procedure to calculate the uncertainty of the method was elaborated; the most significant source of uncertainty for the thin layer EDXRF method is associated with the determination of instrumental sensitivities. The error associated with the determination, expressed as expanded uncertainty (in %), varied from 15.4% for low element concentrations (2.5-5 μg/L) to 5.4% for the higher concentration range (20-25 μg/L).

DINAMIKA POLITIK PERSETUJUAN BERSAMA TENTANG PENETAPAN DESA ADAT DI KABUPATEN ROKAN HULU TAHUN 2014

2017 ◽  
Vol 15 (1) ◽  
pp. 21
Author(s):  
Haryo Suganda ◽  
Raja Muhammad Amin
Keyword(s):  
Regulatory Region ◽  
Field Research ◽  
Analysis Techniques ◽  
Political Dynamics ◽  
Political Interests ◽  
Wide Range ◽  
Information Method ◽  
Qualitative Descriptive ◽  
The Village

This study is motivated the identification of policies issued by the regional Governmentof Rokan Hulu in the form of Regulatory region number 1 by 2015 on the determination of thevillage and Indigenous Village. Political dynamics based on various interests against themanufacture of, and decision-making in the process of formation of the corresponding localregulations determination of Indigenous Villages in the Rokan Hulu is impacted to a verysignificantamount of changes from the initial draft of the number i.e. 21 (twenty one) the villagebecame Customary 89 (eighty-nine) the Indigenous Villages who have passed. Type of thisresearch is a qualitative descriptive data analysis techniques. The research aims to describe theState of the real situation in a systematic and accurate fact analysis unit or related research, aswell as observations of the field based on the data (information). Method of data collectionwas done with interviews, documentation, and observations through fieldwork (field research).The results of the research on the process of discussion of the draft local regulations andmutual agreement about Designation of Indigenous Villages in the Rokan Hulu is, showed thatthe political dynamics that occur due to the presence of various political interests, rejectionorally by Villagers who were judged to have met the requirements of Draft Regulations to beformulated and the area for the set to be Indigenous Villages, and also there is a desire fromsome villages in the yet to Draft local regulations in order to set the Indigenous village , there isa wide range of interests of these aspects influenced the agreement to assign the entire localVillage which is in the Rokan Hulu become Indigenous village, and the village of Transmigrationinto administrative Villages where the initiator of the changes in the number of IndigenousVillages in the Rokan Hulu it is the desire of the local Government of its own.

Numerical evaluation of hydrodynamic characteristics of planing hulls by using a hybrid method

2021 ◽  
pp. 147509022199024
Author(s):  
Emre Kahramanoglu ◽  
Silvia Pennino ◽  
Huseyin Yilmaz
Keyword(s):  
Experimental Data ◽  
Hybrid Method ◽  
Design Stage ◽  
Hydrodynamic Characteristics ◽  
Calm Water ◽  
Preliminary Design Stage ◽  
Reduction Function ◽  
Hull Forms ◽  
Good Agreement

The hydrodynamic characteristics of the planing hulls in particular at the planing regime are completely different from the conventional hull forms and the determination of these characteristics is more complicated. In the present study, calm water hydrodynamic characteristics of planing hulls are investigated using a hybrid method. The hybrid method combines the dynamic trim and sinkage from the Zarnick approach with the Savitsky method in order to calculate the total resistance of the planing hull. Since the obtained dynamic trim and sinkage values by using the original Zarnick approach are not in good agreement with experimental data, an improvement is applied to the hybrid method using a reduction function proposed by Garme. The numerical results obtained by the hybrid and improved hybrid method are compared with each other and available experimental data. The results indicate that the improved hybrid method gives better results compared to the hybrid method, especially for the dynamic trim and resistance. Although the results have some discrepancies with experimental data in terms of resistance, trim and sinkage, the improved hybrid method becomes appealing particularly for the preliminary design stage of the planing hulls.

scholarly journals Recent Developments in the Determination of Biomarkers of Tobacco Smoke Exposure in Biological Specimens: A Review

2021 ◽  
Vol 18 (4) ◽  
pp. 1768
Author(s):  
Hernâni Marques ◽  
Pedro Cruz-Vicente ◽  
Tiago Rosado ◽  
Mário Barroso ◽  
Luís A. Passarinha ◽  
...  
Keyword(s):  
Tobacco Smoke ◽  
Solid Phase ◽  
Smoke Exposure ◽  
Tobacco Smoke Exposure ◽  
World Health ◽  
Second Hand Smoke ◽  
Tobacco Exposure ◽  
Wide Range ◽  
Recent Developments

Environmental tobacco smoke exposure (ETS) and smoking have been described as the most prevalent factors in the development of certain diseases worldwide. According to the World Health Organization, more than 8 million people die every year due to exposure to tobacco, around 7 million due to direct ETS and the remaining due to exposure to second-hand smoke. Both active and second-hand exposure can be measured and controlled using specific biomarkers of tobacco and its derivatives, allowing the development of more efficient public health policies. Exposure to these compounds can be measured using different methods (involving for instance liquid- or gas-chromatographic procedures) in a wide range of biological specimens to estimate the type and degree of tobacco exposure. In recent years, a lot of research has been carried out using different extraction methods and different analytical equipment; this way, liquid–liquid extraction, solid-phase extraction or even miniaturized procedures have been used, followed by chromatographic analysis coupled mainly to mass spectrometric detection. Through this type of methodologies, second-hand smokers can be distinguished from active smokers, and this is also valid for e-cigarettes and vapers, among others, using their specific biomarkers. This review will focus on recent developments in the determination of tobacco smoke biomarkers, including nicotine and other tobacco alkaloids, specific nitrosamines, polycyclic aromatic hydrocarbons, etc. The methods for their detection will be discussed in detail, as well as the potential use of threshold values to distinguish between types of exposure.

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