scholarly journals The Process of Separating Buckwheat and Wheat Grain in a Pneumatic Cone Separator in the Context of Sustainable Agriculture

Processes ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 59
Author(s):  
Ewelina Kolankowska ◽  
Dariusz Jan Choszcz ◽  
Piotr Markowski ◽  
Patrycjusz Sebastian Reszczyński ◽  
Adam Józef Lipiński

In machines and devices used for separating and cleaning seed mixtures, the components of such mixtures can be separated in a stream of air. The efficiency of separation of a two-component (model) mixture containing wheat kernels and buckwheat nutlets was investigated. The main crop seeds and other crop seeds imitating impurities accounted for 80% and 20% (w/w), respectively. The experiment involved a pneumatic cleaning device with an immobile conical surface, designed by the authors, where mixture components are separated in a stream of air. The seed mixture was separated in a separator with the shape of an inverted cone, where the seeds were set into motion by a stream of air. The separation efficiency of the analyzed two-component mixture in the designed separator exceeded 78%. Regression equations describing the separation efficiency index of the entire seed mixture (ε) and the separation efficiency of the main crop seeds (ηp) and seeds imitating impurities (ηz) were derived. The coefficient of determination (R2) for the above regression equations describing the separation efficiency of the mixture components (main crop seeds and seeds imitating impurities) and the separation efficiency index of the entire seed mixture ranged from 0.81 to 0.94. This result indicates that the developed equations were characterized by satisfactory and highly satisfactory fit to empirical data, and that they can be applied to accurately predict the quality of the seed separation process in the cleaning device designed by the authors. The developed equations can be effectively used to model and automatically control separation processes in the proposed separator.

2020 ◽  
Vol 12 (7) ◽  
pp. 3051
Author(s):  
Dariusz Jan Choszcz ◽  
Patrycjusz Sebastian Reszczyński ◽  
Ewelina Kolankowska ◽  
Stanisław Konopka ◽  
Adam Lipiński

Pneumatic separation is one of the available methods for cleaning seed mixtures. Variously shaped seeds, including spherical (vetch), elongated (wheat), and pyramid-shaped seeds (buckwheat), were analyzed in this study. A seed mixture containing 80% of main crop seeds and 20% of other crop seeds imitating impurities was separated in a pneumatic separator with the shape of an inverted cone in a stream of air. The regression equations describing the separation efficiency of the main crop seeds and other crop seeds imitating impurities (η) and the separation efficiency index (ε) were characterized by high and very high fit to empirical data. The coefficient of determination for the analyzed seed mixtures ranged from 0.71 to 0.99. The conical separator supported effective separation of seed mixture components in a stream of air.


1997 ◽  
Vol 90 (4) ◽  
pp. 679-681
Author(s):  
F. SAIJA ◽  
G. FIUMARA ◽  
P.V. GIAQUINTA

2017 ◽  
Vol 23 (2) ◽  
pp. 218-230 ◽  
Author(s):  
Xiaoying Zhu ◽  
Renbi Bai

Background: Bioactive compounds from various natural sources have been attracting more and more attention, owing to their broad diversity of functionalities and availabilities. However, many of the bioactive compounds often exist at an extremely low concentration in a mixture so that massive harvesting is needed to obtain sufficient amounts for their practical usage. Thus, effective fractionation or separation technologies are essential for the screening and production of the bioactive compound products. The applicatons of conventional processes such as extraction, distillation and lyophilisation, etc. may be tedious, have high energy consumption or cause denature or degradation of the bioactive compounds. Membrane separation processes operate at ambient temperature, without the need for heating and therefore with less energy consumption. The “cold” separation technology also prevents the possible degradation of the bioactive compounds. The separation process is mainly physical and both fractions (permeate and retentate) of the membrane processes may be recovered. Thus, using membrane separation technology is a promising approach to concentrate and separate bioactive compounds. Methods: A comprehensive survey of membrane operations used for the separation of bioactive compounds is conducted. The available and established membrane separation processes are introduced and reviewed. Results: The most frequently used membrane processes are the pressure driven ones, including microfiltration (MF), ultrafiltration (UF) and nanofiltration (NF). They are applied either individually as a single sieve or in combination as an integrated membrane array to meet the different requirements in the separation of bioactive compounds. Other new membrane processes with multiple functions have also been developed and employed for the separation or fractionation of bioactive compounds. The hybrid electrodialysis (ED)-UF membrane process, for example has been used to provide a solution for the separation of biomolecules with similar molecular weights but different surface electrical properties. In contrast, the affinity membrane technology is shown to have the advantages of increasing the separation efficiency at low operational pressures through selectively adsorbing bioactive compounds during the filtration process. Conclusion: Individual membranes or membrane arrays are effectively used to separate bioactive compounds or achieve multiple fractionation of them with different molecule weights or sizes. Pressure driven membrane processes are highly efficient and widely used. Membrane fouling, especially irreversible organic and biological fouling, is the inevitable problem. Multifunctional membranes and affinity membranes provide the possibility of effectively separating bioactive compounds that are similar in sizes but different in other physical and chemical properties. Surface modification methods are of great potential to increase membrane separation efficiency as well as reduce the problem of membrane fouling. Developing membranes and optimizing the operational parameters specifically for the applications of separation of various bioactive compounds should be taken as an important part of ongoing or future membrane research in this field.


Author(s):  
Nabarun Deb ◽  
Sujayam Saha ◽  
Adityanand Guntuboyina ◽  
Bodhisattva Sen

Agronomy ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 938
Author(s):  
Ladislav Menšík ◽  
Lukáš Hlisnikovský ◽  
Pavel Nerušil ◽  
Eva Kunzová

The aim of the study was to compare the concentrations of risk elements (As, Cu, Mn, Ni, Pb, Zn) in alluvial soil, which were measured by a portable X-ray fluorescence analyser (pXRF) in situ (FIELD) and in the laboratory (LABORATORY). Subsequently, regression equations were developed for individual elements through the method of construction of the regression model, which compare the results of pXRF with classical laboratory analysis (ICP-OES). The accuracy of the measurement, expressed by the coefficient of determination (R2), was as follows in the case of FIELD–ICP-OES: Pb (0.96), Zn (0.92), As (0.72), Mn (0.63), Cu (0.31) and Ni (0.01). In the case of LABORATORY–ICP-OES, the coefficients had values: Pb (0.99), Zn (0.98), Cu and Mn (0.89), As (0.88), Ni (0.81). A higher dependence of the relationship was recorded between LABORATORY–ICP-OES than between FIELD–ICP-OES. An excellent relationship was recorded for the elements Pb and Zn, both for FIELD and LABORATORY (R2 higher than 0.90). The elements Cu, Mn and As have a worse tightness in the relationship; however, the results of the model have shown its applicability for common use, e.g., in agricultural practice or in monitoring the quality of the environment. Based on our results, we can say that pXRF instruments can provide highly accurate results for the concentration of risk elements in the soil in real time for some elements and meet the principle of precision agriculture: an efficient, accurate and fast method of analysis.


2015 ◽  
Vol 10 (2) ◽  
pp. 67 ◽  
Author(s):  
Pasquale Campi ◽  
Francesca Modugno ◽  
Alejandra Navarro ◽  
Fausto Tomei ◽  
Giulia Villani ◽  
...  

The performance of a water balance model is also based on the ability to correctly perform simulations in heterogeneous soils. The objective of this paper is to test CRITERIA and AquaCrop models in order to evaluate their suitability in estimating evapotranspiration at the field scale in two types of soil in the Mediterranean region: non-stony and stony soil. The first step of the work was to calibrate both models under the non-stony conditions. The models were calibrated by using observations on wheat crop (leaf area index or canopy cover, and phenological stages as a function of degree days) and pedo-climatic measurements. The second step consisted in the analysing the impact of the soil type on the models performances by comparing simulated and measured values. The outputs retained in the analysis were soil water content (at the daily scale) and crop evapotranspiration (at two time scales: daily and crop season). The model performances were evaluated through four statistical tests: normalised difference (D%) at the seasonal time scale; and relative root mean square error (RRMSE), efficiency index (EF), coefficient of determination (r<sup>2</sup>) at the daily scale. At the seasonal scale, values of D% were less than 15% in stony and on-stony soils, indicating a good performance attained by both models. At the daily scale, the RRMSE values (2) indicate the inadequacy of AquaCrop to simulate correctly daily evapotranspiration. The higher performance of CRITERIA model to simulate daily evapotranspiration in stony soils, is due to the soil submodel, which requires the percentage skeleton as an input, while AquaCrop model takes into account the presence of skeleton by reducing the soil volume.


1977 ◽  
Vol 55 (1) ◽  
pp. 29-33 ◽  
Author(s):  
Stefan Weigl ◽  
John Warkentin

Triphenylmethylcyclopentadiene exists as a mixture of isomers, the minor and major components of which are shown to be 1-triphenylmethylcyclopentadiene (1) and 2-triphenylmethyl-cyclopentadiene (2), respectively.Direct irradiation of a mixture of 1 and 2 led to formation of 5,6,6,-triphenylbicyclo[3.1.0]hex-2-ene (3) via rearrangement of 1. Acetophenone-sensitized irradiation of the same mixture gave 3 as well as a two component mixture of photodimers of 1 and/or 2. Results are interpreted in terms of the di-π-methane rearrangement mechanism.


2018 ◽  
Vol 18 (5-6) ◽  
pp. 505-524 ◽  
Author(s):  
Rosaria Simone ◽  
Maria Iannario

In the analysis of questionnaire-based evaluation of sport preferences, measurements of sport participation, opinions on social implications such as resurgence of racism, violence in stadiums and doping, the need arises to establish connections among motivations, subjects’ characteristics and responses. In this setting, the article deals with a selection of statistical models suitable to analyse sport rating data in which clusters of opposite responses are observed. Specifically, a two-component mixture of inverse hypergeometric (MIHG) distributions will be introduced and tested against competing models in order to yield a multifold interpretation of results. The ultimate comparative analysis will consider discrete models with a specific focus on those accounting for both uncertainty and feeling of self-evaluation in presence of inflation at the extreme categories. After a brief review of the methods, the proposal will be discussed both on ranking and rating data on the basis of two surveys on sport preferences and on measurements of sport activity: the identification of clusters of respondents with opposite choices will be investigated also in terms of covariates by comparing fitting performances of the selected models. The conclusions and insights offered by the study can be exploited to design plans of action for some specific policy or marketing strategy.


2020 ◽  
Author(s):  
Xun Gu

AbstractCurrent cancer genomics databases have accumulated millions of somatic mutations that remain to be further explored, faciltating enormous high throuput analyses to explore the underlying mechanisms that may contribute to malignant initiation or progression. In the context of over-dominant passenger mutations (unrelated to cancers), the challenge is to identify somatic mutations that are cancer-driving. Under the notion that carcinogenesis is a form of somatic-cell evolution, we developed a two-component mixture model that enables to accomplish the following analyses. (i) We formulated a quasi-likelihood approach to test whether the two-component model is significantly better than a single-component model, which can be used for new cancer gene predicting. (ii) We implemented an empirical Bayesian method to calculate the posterior probabilities of a site to be cancer-driving for all sites of a gene, which can be used for new driving site predicting. (iii) We developed a computational procedure to calculate the somatic selection intensity at driver sites and passenger sites, respectively, as well as site-specific profiles for all sites. Using these newly-developed methods, we comprehensively analyzed 294 known cancer genes based on The Cancer Genome Atlas (TCGA) database.


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