scholarly journals Comparação de técnicas analíticas para a extração de potássio de amostras de tecido vegetal com água e soluções ácidas concentrada e diluída

2018 ◽  
Vol 35 (2) ◽  
pp. 45
Author(s):  
Alberto Carlos De Campos Bernardi ◽  
Sílvia Harumi Oka ◽  
Gilberto Batista de Souza

The improvement of analytical methods makes the search for new technologies fast, accurate and low cost are constantly being reviewed and evaluated. The main objective of this research was to compare three forms of extraction of potassium (nitro-perchloric decomposition, extraction with water and extraction with diluted solution of HCl) of plant tissues samples of Tanzania grass (Panicum maximum cv. Tanzania) and alfalfa (Medicago sativa cv. Crioula).The methods of K extraction of Tanzania grass and alfalfa plant  tissue samples in acid solution or diluted with water were equivalent to the traditional method of nitro-perchloric decomposition and can replace it.

2011 ◽  
Vol 94 (6) ◽  
pp. 1896-1905 ◽  
Author(s):  
James D Crutchfield ◽  
John H Grove

Abstract A reusable catalytic reductor consisting of 96 copperized-cadmium pins attached to a microplate lid was developed to simultaneously reduce nitrate (NO3–) to nitrite (NO2–) in all wells of a standard microplate. The resulting NO2– is analyzed colorimetrically by the Griess reaction using a microplate reader. Nitrate data from groundwater samples analyzed using the new device correlated well with data obtained by ion chromatography (r2 = 0.9959). Soil and plant tissue samples previously analyzed for NO3– in an interlaboratory validation study sponsored by the Soil Science Society of America were also analyzed using the new technique. For the soil sample set, the data are shown to correlate well with the other methods used (r2 = 0.9976). Plant data correlated less well, especially for samples containing low concentrations of NO3–. Reasons for these discrepancies are discussed, and new techniques to increase the accuracy of the analysis are explored. In addition, a method is presented for analyzing NO3– in physiological fluids (blood serum and urine) after matrix modification with Somogyi's reagent. A protocol for statistical validation of data when analyzing samples with complex matrixes is also established. The simplicity, adaptability, and low cost of the device indicate its potential for widespread application.


2015 ◽  
Vol 39 (3) ◽  
pp. 788-793 ◽  
Author(s):  
Bruna Wurr Rodak ◽  
Milton Ferreira de Moraes ◽  
João Augusto Lopes Pascoalino ◽  
Adilson de Oliveira Junior ◽  
Cesar de Castro ◽  
...  

In comparison with other micronutrients, the levels of nickel (Ni) available in soils and plant tissues are very low, making quantification very difficult. The objective of this paper is to present optimized determination methods of Ni availability in soils by extractants and total content in plant tissues for routine commercial laboratory analyses. Samples of natural and agricultural soils were processed and analyzed by Mehlich-1 extraction and by DTPA. To quantify Ni in the plant tissues, samples were digested with nitric acid in a closed system in a microwave oven. The measurement was performed by inductively coupled plasma/optical emission spectrometry (ICP-OES). There was a positive and significant correlation between the levels of available Ni in the soils subjected to Mehlich-1 and DTPA extraction, while for plant tissue samples the Ni levels recovered were high and similar to the reference materials. The availability of Ni in some of the natural soil and plant tissue samples were lower than the limits of quantification. Concentrations of this micronutrient were higher in the soil samples in which Ni had been applied. Nickel concentration differed in the plant parts analyzed, with highest levels in the grains of soybean. The grain, in comparison with the shoot and leaf concentrations, were better correlated with the soil available levels for both extractants. The methods described in this article were efficient in quantifying Ni and can be used for routine laboratory analysis of soils and plant tissues.


Hoehnea ◽  
2019 ◽  
Vol 46 (1) ◽  
Author(s):  
Carlos André Espolador Leitão

ABSTRACT Glycol methacrylate resin is a very convenient medium used for inclusions of various types of tissue for histological and cytological studies. It provides excellent mechanical support in the sectioning of samples, even the ones with big differences in hardness. Additionally, it allows a large range of stain techniques and histochemical tests. During the infiltration stage, especially if it lasts for several days, the resin may be accidentally polymerized, which may give the impression that the sample has been lost. The present work aims to provide a technique for correcting the position of plant tissues samples embedded in accidentally polymerized glycol methacrylate resin. For this purpose, blocks of resin accidentally polymerized containing plant samples were trimmed and reshaped appropriately. The results were satisfactory and it was possible to obtain good sections of three micrometers thick.


Sensors ◽  
2021 ◽  
Vol 21 (2) ◽  
pp. 357
Author(s):  
Pedro Moura ◽  
José Ignacio Moreno ◽  
Gregorio López López ◽  
Manuel Alvarez-Campana

University campuses are normally constituted of large buildings responsible for high energy demand, and are also important as demonstration sites for new technologies and systems. This paper presents the results of achieving energy sustainability in a testbed composed of a set of four buildings that constitute the Telecommunications Engineering School of the Universidad Politécnica de Madrid. In the paper, after characterizing the consumption of university buildings for a complete year, different options to achieve more sustainable use of energy are presented, considering the integration of renewable generation sources, namely photovoltaic generation, and monitoring and controlling electricity demand. To ensure the implementation of the desired monitoring and control, an internet of things (IoT) platform based on wireless sensor network (WSN) infrastructure was designed and installed. Such a platform supports a smart system to control the heating, ventilation, and air conditioning (HVAC) and lighting systems in buildings. Furthermore, the paper presents the developed IoT-based platform, as well as the implemented services. As a result, the paper illustrates how providing old existing buildings with the appropriate technology can contribute to the objective of transforming such buildings into nearly zero-energy buildings (nZEB) at a low cost.


Micromachines ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 882
Author(s):  
M. Munzer Alseed ◽  
Hamzah Syed ◽  
Mehmet Cengiz Onbasli ◽  
Ali K. Yetisen ◽  
Savas Tasoglu

Civil wars produce immense humanitarian crises, causing millions of individuals to seek refuge in other countries. The rate of disease prevalence has inclined among the refugees, increasing the cost of healthcare. Complex medical conditions and high numbers of patients at healthcare centers overwhelm the healthcare system and delay diagnosis and treatment. Point-of-care (PoC) testing can provide efficient solutions to high equipment cost, late diagnosis, and low accessibility of healthcare services. However, the development of PoC devices in developing countries is challenged by several barriers. Such PoC devices may not be adopted due to prejudices about new technologies and the need for special training to use some of these devices. Here, we investigated the concerns of end users regarding PoC devices by surveying healthcare workers and doctors. The tendency to adopt PoC device changes is based on demographic factors such as work sector, education, and technology experience. The most apparent concern about PoC devices was issues regarding low accuracy, according to the surveyed clinicians.


Weed Science ◽  
2013 ◽  
Vol 61 (1) ◽  
pp. 63-67 ◽  
Author(s):  
R. Bradley Lindenmayer ◽  
Scott J. Nissen ◽  
Philip P. Westra ◽  
Dale L. Shaner ◽  
Galen Brunk

Field bindweed is extremely susceptible to aminocyclopyrachlor compared to other weed species. Laboratory studies were conducted to determine if absorption, translocation, and metabolism of aminocyclopyrachlor in field bindweed differs from other, less susceptible species. Field bindweed plants were treated with 3.3 kBq14C-aminocyclopyrachlor by spotting a single leaf mid-way up the stem with 10 µl of herbicide solution. Plants were then harvested at set intervals over 192 h after treatment (HAT). Aminocyclopyrachlor absorption reached a maximum of 48.3% of the applied radioactivity by 48 HAT. A translocation pattern of herbicide movement from the treated leaf into other plant tissues emerged, revealing a nearly equal aminocyclopyrachlor distribution between the treated leaf, aboveground tissue, and belowground tissue of 13, 14, and 14% of the applied radioactivity by 192 HAT. Over the time-course, no soluble aminocyclopyrachlor metabolites were observed, but there was an increase in radioactivity recovered bound in the nonsoluble fraction. These results suggest that aminocyclopyrachlor has greater translocation to belowground plant tissue in field bindweed compared with results from other studies with other herbicides and other weed species, which could explain the increased level of control observed in the field. The lack of soluble metabolites also suggests that very little metabolism occurred over the 192 h time course.


Kybernetes ◽  
2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Mi Tang ◽  
Hongmei Zhou ◽  
Qingyan Yan ◽  
Ruoyu Li ◽  
Hui Lu

PurposeHealthcare employs informatics to offer its services through information technology where the social network can aid virtual medical learning. Since the usage of the internet and other electronic tools for medical services delivery is at the initial stage, it is essential to examine the factors that condition patients and medical elements in a virtual environment can develop relationship models on the health services. So, the authors have systematically reviewed virtual medical learning and offered some suggestions for the upcoming works. The authors have also discovered gaps in the state-of-the-art papers and provided solutions for them.Design/methodology/approachNumerous novel advancements have changed the old exercise of therapeutic and analytic learning. Virtual spaces have quickly turned into a section of the learning technology vision. Given the importance of its achievements and endless low-cost expansion of the educational system, virtual education has been considered as one of the issues raised by the information communities. Medicine and health are some of the most important fields in virtual technologies. Hence, in this paper, we have used a systematic literature review to deeply examine virtual medical learning. After establishing exclusion and inclusion criteria, an independent systematic search in Google Scholar, ACM, Scopus, Eric, Science Direct, Springer link, Emerald, Global ProQuest and IEEE for relevant studies have been performed, and 21 papers have been analyzed. Detailed data have been mined out of the papers.FindingsThe authors have found that virtual medical learning improves and expands the knowledge core and meaningfully affects the exercise. Virtual learning (VL) has been used in many therapeutic zones, like therapeutic learning, surgery, diagnosing, combining and regularizing processes. It has presented a fundamental access point and a referral mechanism for all of a course's component communities. It can also simplify communicative education, allowing learners to get abilities before applying them in a real-world situation. Also, the communicative characteristics of different VL programs can somehow be like direct teaching.Research limitations/implicationsSome excellent work may be removed owing to applying the filters to select the primary papers. Surveying all the documents on the topic of virtual medical learning is impossible, too. Nevertheless, the authors have tried to present a perfect survey of virtual medical learning. The results will be helpful for scholars to propose better virtual medical learning techniques.Practical implicationsE-learning has become an indispensable additional learning tool in medical education. The introduction of new learning technologies, the exponential growth of Internet usage and the advent of the World Wide Web can change the face of higher education. The results will be helpful for scholars for the upcoming works. The application of a literature review of partial least squares theory was useful for offering comprehensive literary coverage and completing the knowledge development analysis. The authors have backed scholars and experts for better understanding the development of virtual medical learning systems via presenting comparative data and scrutinizing the present advances.Originality/valueThe paper enhances intellectual knowledge by improving the conception of virtual medical learning. It informs the development, use of virtual medical learning and the upcoming works. The lack of comprehensive papers in this field has increased the importance of this paper. The present paper can handle the pace of publications.


2018 ◽  
Vol 7 (2.8) ◽  
pp. 419
Author(s):  
K Geetha ◽  
P Prabha ◽  
C Preetha Devi ◽  
S Priyadharshini ◽  
S Tamilselvan

Now a days, Industries are more equipped with automatic system. Fire monitoring is one of the applications where continuous monitoring of temperature and humidity is essential to detect the fire in the industry. Fire detection is very much necessary to protect both the industry and to conserve environment and livelihood of human. This paper presents an algorithm to detect the fire in the industry based on ZigBee and GPRS wireless sensor network which provides low cost, low maintenance and good quality service when compared with the traditional method. The hardware circuitry of proposed solution is based on microcontroller, temperature sensor along with ZigBee and GPRS modules.


Author(s):  
Sergio Ferreira do Amaral ◽  
Luciana Ozello Baratti ◽  
Daniel Moutinho Bataca ◽  
João Henrique de Augustinis Franco ◽  
José Manuel Martin Rios ◽  
...  

Este é um artigo de um projeto em andamento desenvolvido em parceria com a Diretoria Técnica de Serviços do CPqD Telecom & IT Solutions e a Faculdade de Educação da UNICAMP, que objetiva estabelecer um serviço de apoio a distância aos professores em sala de aula em 03 Escolas da região de Barão Geraldo em Campinas/ SP , para utilizar a TV Digital Interativa como ferramenta de busca e desenvolvimento de conteúdo multimídia interativo nas práticas pedagógicas. Fundamentalmente esta ferramenta será de fácil uso por utilizar como terminal de escolha e exibição um televisor colocado nas salas de aula das escolas e controlado por controle remoto. O professor poderá interagir com o conteúdo exibido no televisor de modo a obter uma programação não linear que se desenvolverá conforme o seu projeto pedagógico. As principais características do serviço são a facilidade de uso, fornecimento a distância de material multimídia interativo, baixo custo de implantação e grande área geográfica de cobertura, proporcionada pela disponibilidade quase total de sinal de televisão no território nacional. Este serviço é parte de um conjunto de serviços de teleducação que estão sendo desenvolvidos para o futuro Sistema de TV Digital terrestre que será implantado no Brasil. Palavras-chave: Educação a distância; TV digital interativa; Novas tecnologias aplicadas na educação; Tecnologia da informação e comunicação Abstract This is an article of a developed in progress project in would seem the Direction Technique of Services of the CPqD Telecom & IT Solutions and the College of Education of the UNICAMP, that objective in the distance to establish a support services to the teacher in classroom in 03 Schools of the region of Barão Geraldo in Campinas, SP, to use the Interactive Digital TV as a search tool and practical development of interactive multimedia content in the pedagogical practical ones. Basically this tool will be easy to use as a terminal of choice and exhibition a television set placed in the school’s classrooms and controlled for remote control. The teacher be able to interact with according to the content shown in the television set in order to get a non linear programme that will develop this pedagogical project. The main services characteristics are the easiness of use, supply of the interactive at distance multimedia material, low cost of implantation and covering of a great geographic area, for the almost total availability of signal of television in domestic territory. This service is part of a set of TV-education services that are being developed for the coming System of terrestrial Digital TV that will be implanted in Brazil. Key words: Distance Education; Interactive Digital TV; New Technologies applied in Education


Molecules ◽  
2021 ◽  
Vol 26 (23) ◽  
pp. 7271
Author(s):  
Tomasz Baran ◽  
Alberto Visibile ◽  
Michael Busch ◽  
Xiufang He ◽  
Szymon Wojtyla ◽  
...  

This work aims at reviewing the most impactful results obtained on the development of Cu-based photocathodes. The need of a sustainable exploitation of renewable energy sources and the parallel request of reducing pollutant emissions in airborne streams and in waters call for new technologies based on the use of efficient, abundant, low-toxicity and low-cost materials. Photoelectrochemical devices that adopts abundant element-based photoelectrodes might respond to these requests being an enabling technology for the direct use of sunlight to the production of energy fuels form water electrolysis (H2) and CO2 reduction (to alcohols, light hydrocarbons), as well as for the degradation of pollutants. This review analyses the physical chemical properties of Cu2O (and CuO) and the possible strategies to tune them (doping, lattice strain). Combining Cu with other elements in multinary oxides or in composite photoelectrodes is also discussed in detail. Finally, a short overview on the possible applications of these materials is presented.


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