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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

臺灣行動支付之挑戰與競爭策略 / Challenges and Competitive Strategies of Mobile Payment in Taiwan

張軒愷, Chang, Hsuan Kai Unknown Date (has links)
全球行動支付交易金額預測將從2013年的2354億美元成長至2017年的7210億,年增率平均35%,而使用人口也將從2.4億增加到4.5億。另外,相較於亞洲其他國家非現金支付比例已高達五、六成,臺灣只有25%,顯示還有很高的成長空間。本研究透過Porter的鑽石模型比較美國、中國、台灣三國在行動支付領域的優勢與挑戰,同時透過Business Canvas拆解台灣行動支付平台廠商的商業模式,藉以了解台灣在行動支付領域的策略以及商業模式運作方法。 本研究的結論認為臺灣雖然在由於法律因素在行動支付市場業務上起步較晚,然而在技術取得面具有後發優勢。在需求面,臺灣的消費者準備度亦高,因此主要的挑戰在於產業鏈上待整合與國內內需低落,尚可透過跨境電商的方式取得突破。另一方面,台灣的廠商應該考慮選擇HCE而非TSM平台,同時思考如何吸引具有強大網路效應與平台效應的族群,並在國外廠商進入前搶先佈局。本研究屬初探性質,可作為未來研究行動支付相關研究之基礎。 / Global mobile payment market is forecasted to boom from 2.354 trillions in 2013 to 7.21 trillion in 2015, averagely at 25% annual growth rate. Compared to 50-60% non-cash payment in other Asian countries Taiwan only has 25% non-cash payment, which suggests high potential growth. This research conducted Diamond Model to compare the advantages and challenges in the domain of mobile payment in the U.S., China and Taiwan. Additionally, inspecting a Taiwanese mobile payment platform company by Business Canvas to understand business models and strategies in Taiwan. The conclusion of the research suggested that though Taiwan has slower development at mobile payment in consequence of legislation factor, it has the late-developing advantage in the acquisition of technology. In demand side, Taiwan also has high customer preparation, thus the main challenges are the integration of supply chain and limited domestic need, which could be overcome by developing international e-commerce. Furthermore, Taiwanese mobile payment companies shall consider adopt HCE platform instead of TSM platform, at the mean time find out how to appeal the groups with strong network effect and platform effect, and speed up deployment before international companies access to Taiwan. This research plays a role of advanced research in mobile payment, and could be a foundation for further related researches.
2

En analys av centralkylan i Slakthusområdet i Stockholm / An analysis of the central cooling system at Slakthusområdet in Stockholm

Tekleab, Binyom, Kifle, Fuzum January 2011 (has links)
In Stockholm, Johanneshov the Slaughterhouse area (Slakthusområdet) can be found. A number of companies have gathered there providing the Stockholmers with meat products. This area has a great need for cooling to supply large cold storages. To facilitate this, a central cooling system has been built, supplying the area with effective and safe cooling. The aim of this master thesis study is to give hints to energy efficient and reliable changes that can be put in place at a low marginal cost depending on the future activities in the area. The suggested changes will be presented to the company Bravida (managing the system), which also desires a deeper understanding of the energy flows through the central cooling system. Firstly visiting the site with proper guidance, we have then tried to understand the function of the system including which machines and media that are used. We have described the present design and come up with suggestions on how to improve the cooling system for a more efficient and safer cooling. Account has been taken to the fact that the whole area will be remodelled radically, thus the improvements must give a short payback time or have a value even after the remodelling. A conclusion drawn from our calculations is that the efficiency of the central cooling is low. The average COP 2(Coefficient of performance in the cooling mode) is around 1,2 which is low. That results in a high electric consumption. Apart from this unnecessarily high water consumption for the cooling tower has been has been observed. We have come up with some ideas to improve the system like:  Enhancing the insulation of the buildings, the pipes and the substation components.  Changing parts in the system like pumps valves and fluids  Introducing a new system for cooling the machines – a bedrock storage so that the heat can be utilized / I stadsdelen Johanneshov finner vi Slakthusområdet, där har ett konglomerat av företag (ca 240 st.) samlats för att förse Stockholm med kött, fläsk och charkprodukter. I detta område finns ett behov av stora kylrum och frysrum. För att underlätta det har man byggt ett centralkylsystem, som levererar effektiv och säker kyla. Syftet med detta examensarbete är att ge förslag på energieffektiva och driftsäkra åtgärder som kan iscensättas med små marginalkostnader beroende på områdets fortsatta verksamhet. Föreslagna driftsåtgärder presenteras för Bravida (driftansvarigt) som också önskar få en fördjupad inblick i centralkylans energiflöden. Genom besök på plats och guidning på området, har vi försökt att förstå hur hela systemet är uppbyggt, vilka aggregat och medier man använder. Vi har beskrivit den nuvarande utformningen och sedan kommit med idéer på vilka åtgärder man kan vidta för en effektivare, säkrare kyl- och frysproduktion. Hänsyn har tagits till att området står inför stora förändringar, så de åtgärder som föreslås är de som kan ge en kort återbetalningstid eller ha ett restvärde efter förändringarna. Metoderna för att komma fram till slutsatser var bl.a. beräkningar utgående från mätdata i bildform som vi fick av fastighetskontoret. Dessa bilder har omvandlats via flera OCR-dataprogram till Excel-filer. Ur dessa Excel-filer har vi sedan kunnat dra vissa slutsatser om energiförbrukningen i Slakthusområdet. Slutsatserna vi drog av dessa beräkningar är att centralkylan har en dålig verkningsgrad. Medelköldfaktorn (COP 2: Coefficient Of Performance) blir bara 1,2 vilket är lågt. Det medför att elenergiförbrukningen blir hög. Dessutom har man en onödig förbrukning av vatten i kylsystemets kyltorn. Vi har kommit med några idéer till förbättringar som:  Isoleringsförbättringar av klimatskal, rör och undercentraler.  Utbyte av delar i systemet som pumpar och ventiler.  Ett nytt avkylningssystem med ett bergvärmelager där den bortkylda värmen används.  Möjligheten att nyttja kyllagring.
3

The Effectiveness of Utilizing the Treatment Support Measure for Treatment Planning in Youth Mental Health Services

Garland, Adam D. 01 December 2017 (has links)
The use of treatment support tools to enhance client outcomes is not well understood in the youth treatment literature. Adult outcome researchers have found that the use of Clinical Support Tools (CST) leads to improved outcomes with clients identified as at risk for treatment failure. However, the American Psychological Association (APA) has noted that understanding important client factors that influence treatment is critical during the clinical formulation and treatment planning phase of therapy. No studies to date have evaluated the effectiveness of utilizing a CST as a treatment planning tool with youth clients. The purpose of this study was to evaluate the effectiveness of the Treatment Support Measure, a CST, for the purpose of treatment planning rather than as a reaction to clients who became at-risk for treatment failure. Two hundred and eight youth participants and their caregivers from three outpatient community mental health clinics were randomly assigned to a feedback (TSM-FB) or Non-FB condition. All participants completed the Youth Outcome Questionnaire (Y-OQ) at each session. The TSM was administered to clients in the TSM-FB condition during the intake session. Only therapists whose clients were in the TSM-FB condition received TSM and Y-OQ data. A multilevel model was created to evaluate for differences between conditions on the dependent variable. The initial randomization failed to create similar groups at intake and a statistically and clinically significant difference was detected on the Y-OQ at intake. As such, no conclusions can be drawn for hypotheses tied to the primary dependent variable. Premature termination (PT) rates were significantly lower for the TSM-FB condition when defined as attending more than one session. Contrastingly, there was no difference between conditions on PT when defining PT based on the therapist's opinion. A significant minority of therapists (40%) found that the TSM was useful for treatment planning compared to 10% which did not.
4

Organic Vapor Sensing Using High Frequency Thickness Shear Mode Resonators

Williams, Randolph 11 July 2005 (has links)
Thickness shear mode (TSM) sensors, also known as quartz crystal micro-balances (QCM) are a class of acoustic wave sensors that have been used for gas/vapor sensing. Fast and sensitive chemical vapor sensing, specifically of hydrocarbon vapors is an important application for these vapor sensors. The TSM sensors typically used have a lower sensitivity compared with other acoustic wave sensors. This thesis describes the development of high sensitivity organic vapor sensors using thin polymer film coatings on TSM devices. Commercially available AT-quartz TSM devices were milled leaving a thin quartz membrane surrounded by a thicker outer ring. This resulted in an increased frequency and a consequent increase in sensitivity, as described by the Sauerbrey equation. The TSM sensors were then coated with thin sensing films of rubbery polymers. Isothermal experiments at room temperature were conducted. A fully instrumented and automated test bed consisting of a temperature-controlled organic vapor dilution system, a precision impedance analyzer, and computer based data acquisition was developed and used to evaluate the performance of the coated TSM devices. The TSM devices compared in this study were AT cut with fundamental resonant frequencies of 10, 20, and 96 MHz. The results of tests conducted are presented to demonstrate increase in sensitivity for higher fundamental frequency TSM devices. 96 MHz TSM resonators were found to be 8 to 27 times more sensitive than 10 MHz resonators. Sensitivity was limited by the difficulty in coating sensing layers and damping of the resonator. Additionally, each sensor was evaluated and compared in terms of detection limit and noise level. 96 MHz resonators had higher noise levels than 10 MHz or 20 MHz resonators; as a result, 96 MHz resonators did not show significant improvements in LOD. Also, response times for 96 MHz resonators were quicker than 10 MHz or 20 MHz resonators and response times generally decreased with analyte concentration. Several rubbery polymer films as well as copolymers were investigated to determine which sensing film would have the optimal performance in terms of response time, recovery, reproducibility, repeatability, frequency noise, and baseline drift. The organic vapors studied were benzene, toluene, hexane, cyclohexane, heptane, dichloroethane, and chloroform at levels ranging from 0.2 to over 13.7 volume percentage in nitrogen gas. The Butterworth-VanDyke (BVD) equivalent circuit model was used to model both the perturbed and unperturbed TSM resonator. Monitoring the sensor response through the equivalent circuit model allowed for discriminating between the organic vapors. Vapor discrimination, in turn, depended upon the changes in the resistance parameter. Finally, the vapor liquid equilibrium at the polymer solvent interface was utilized to correct for perturbations, due to temperature changes, in the sensor response.
5

Statistický software pro analýzu časových řad

Sianchuk, Raman January 2008 (has links)
Vzhledem k existenci obrovského množství statistických programů vzniká docela logická otázka: který z nich je lepší. Samozřejmě tady záleží na konkrétní zkoumané úloze. V této práci se budu věnovat analýze časových řad. Vzhledem k tomu, že na trhu jsou jak placené tak i neplacené programy bude třeba se podívat na několik představitelů obou skupin. Závěrem své práce ohodnotím tyto softwary podle několika kritérii. Posuzovat budu z hlediska potřeb studenta Vysoké Školy Ekonomické. Studenti VŠE tady mají možnost pracovat především se Statgraphicsem a GiveWinem, další dva softwary Matrixer a Gretl jsou zprostředkovány jako freeware a jsou dostupné zdarma na internetu, dále budu porovnávat i placené programy EViews a Time Series Modelling, s cílem posoudit jestli se vyplatí koupit licenci na tyto softwary nebo je lepší použít školní program anebo bude lepší stáhnout freeware. Rozbor programu provedu pomocí tři aspektů: obecný popis programů, příkladu ARIMA a příkladu SARIMA.
6

Avaliação de Métodos para a Estimativa da Acidez Potencial para os solos dos Estados do Rio Grande do Sul e Mato Grosso / Evaluation of methods for estimating potential acidity in soils of Rio Grande do Sul and Mato Grosso States, Brazil

Guidotti, Rosane Maria Morales 30 September 2013 (has links)
Made available in DSpace on 2014-08-20T13:25:38Z (GMT). No. of bitstreams: 1 dissertacao_rosane_guidotti.pdf: 1652873 bytes, checksum: e165e27a1c291c18f1a683f1efc62a01 (MD5) Previous issue date: 2013-09-30 / Teaching and research activities in different areas of knowledge employ various chemicals substances, some of which are considered dangerous, offering potential risk to those who manipulate it or risk to the environment. The estimation of potential acidity (H + Al) in soils, made by SMP method uses two toxic reagents, p-nitrophenol and potassium chromate. To minimize toxic effect of these reagents, a new method called Sikora was proposed and tested in American soils, with positive results, which replaced them, respectively, by imidazole and the MES (2-N-morpholino ethanesulfonic acid monohydrate), not considered harmful. Sikora method has been tested in some Brazilian soils of Rio Grande do Sul State (RS) and from Central Brazil (Cerrado), and did not present a good correlation. For this reason, the Sikora method was modified and calibrated for these same soils and called Santa Maria buffer (TSM). This study aimed to evaluate the effectiveness of the original Sikora method and his version TSM in the estimation of the soil potential acidity in order to replace the SMP method calibrated for RS and Santa Catarina (SC) States, in a large group of soils, from RS and Mato Grosso (MT) States, with contrasting chemical and physical characteristics. The methods were tested using 110 soil samples from MT and 103 from RS, collected at 0-20 cm depth, in cultivated and uncultivated areas. The results were submitted to correlation analysis and descriptive statistics analysis. A second degree polynomial was adjusted to compare the potential acidity titrated with the pH values obtained with the three methods. Among methods, the higher accuracy in predicting the potential acidity was observed in the following order: SMP > TSM > Sikora, for both soils from RS State Southern and Planalto region as well for those of MT state. In RS state, the TSM method showed to be feasible to estimate potential acidity (H + Al) for soils of both regions, allowing the adoption of a single mathematical model. Only the SMP method presented universality in estimating potential acidity (H + Al) for soils of the two states, RS and MT. Sikora and TSM methods reproduced pH values obtained with SMP method for MT soils and therefore can be used for limestone recommendation. For RS State, the TSM method was more efficient than the Sikora method on the reproduction of soils pH values obtained with the SMP method, being the most suitable to replace SMP method in soil analysis laboratories and therefore to be used on limestone recommendation. / As atividades de ensino e pesquisa nas diversas áreas do conhecimento empregam várias substâncias químicas, sendo algumas consideradas perigosas, oferecendo risco potencial aqueles que as manipulam e ao meio ambiente. A estimativa da acidez potencial (H + Al) em solos, feita pelo método SMP, utiliza dois reagentes de caráter tóxico, o p-nitrofenol e o cromato de potássio. Para minimizar o efeito tóxico destes reagentes, foi proposto e testado com resultados positivos em solos americanos um método denominado Sikora, que os substituiu, respectivamente, pelo imidazol e pelo MES (ácido 2-N-morfolino etanosulfonico monohidratado), considerados menos tóxicos. No Brasil, o método Sikora foi testado em alguns solos do Estado do Rio Grande do Sul (RS) e do Cerrado. Como não apresentou uma boa correlação, o método foi modificado, calibrado para estes mesmos solos e denominado Tampão Santa Maria (TSM). O presente trabalho teve como objetivo avaliar a eficácia do método Sikora original e sua versão TSM na estimativa da acidez potencial num amplo grupo de solos, dos Estados do RS e do Mato Grosso (MT), com características químicas e físicas contrastantes, com vistas à substituição do método SMP calibrado para os Estados do RS e Santa Catarina (SC). Os métodos foram testados em 110 amostras de solos do MT e 103 amostras de solos dos RS, coletados na camada de 0-20 cm, em áreas cultivadas e não cultivadas. Os resultados foram submetidos a análises de correlação e estatística descritiva. Ajustou-se um polinômio de segundo grau para a comparação dos valores de pH obtidos com acidez potencial titulada e os três métodos. A maior acurácia na predição da acidez potencial foi observada na seguinte ordem entre os métodos avaliados: SMP>TSM>Sikora, tanto para solos das regiões Sul e Planalto do RS como para o Estado do MT. No RS, o método TSM mostrou-se viável em estimar acidez potencial (H + Al) para os solos das duas regiões do RS, possibilitando a adoção de um modelo matemático único. Apenas o método SMP apresentou universalidade na estimativa da acidez potencial (H + Al) para os dois Estados, RS e MT. O método Sikora e sua versão TSM reproduziram os valores de pH obtidos com o método SMP para os solos do MT e portanto podem ser usados para a recomendação de calcário. Para os solos do RS, o método TSM mostrou-se mais eficiente do que o método Sikora na reprodução dos valores de pH obtidos com o método SMP, sendo o mais indicado para substituí-lo nos laboratórios de análise de solos deste Estado e na recomendação de calcário.
7

Développement d’un système à ondes acoustiques pour le suivi rhéologique de la polymérisation de protéines. Application à la maladie d’Alzheimer. / Development of an acoustic waves sensor for rheological monitoring of proteins polymerization. Application to Alzheimer's disease.

Didier, Pierre 08 June 2017 (has links)
La mise au point de nouveaux systèmes biocompatibles de suivi des phénomènes de polymérisation de protéines est un enjeu majeur pour la compréhension des mécanismes moléculaires en vue d’une détection et d’un traitement précoce des pathologies dites conformationnelles telles que la maladie d’Alzheimer ou les maladies à prions. Dans ces pathologies, des protéines ou des fragments de celles-ci perdent leur structure, puis s’assemblent en fibres ordonnées au sein d’agrégats. Les mécanismes moléculaires du changement de conformation d'une protéine et sa polymérisation en fibres amyloïdes sont encore largement inconnus. La compréhension de ces mécanismes et le diagnostic sont étroitement liés à la disponibilité d’un concept analytique performant pour le suivi ex vivo de ces phénomènes.Pour répondre à cette problématique, un microsystème a été mis au point pour la détection et le suivi de polymérisation de la protéine tau et du peptide Aß, principaux biomarqueurs de la maladie d’Alzheimer. Le microcapteur est basé sur la propagation d’ondes acoustiques hautes fréquences qui permettent d’extraire les propriétés rhéologiques du milieu cible. En mesurant l’impédance complexe du biocapteur, un traitement du signal dédié permet l’extraction des paramètres viscoélastiques (module élastique et module visqueux). L’étude et le développement de ce microsystème impliquent un savoir-faire pluridisciplinaire en instrumentation : élaboration et conception et modélisation de biocapteurs, conditionnement des signaux et résolution des problèmes inverses associés.Tout d’abord, le capteur a été optimisé pour améliorer sa sensibilité et permettre le suivi de polymérisation. Un travail sur la faisabilité du système a montré la possibilité de discriminer des solutions de protéines de différentes concentrations. La finalité du système de détection étant la détection simultanée des différents biomarqueurs à l’origine de la maladie d’Alzheimer, un capteur multi-électrodes permettant la détection de ces différents analytes a été développé. / The development of new biocompatible systems for monitoring protein polymerization processes is a key issue for understanding the molecular mechanisms of detection and for early treatment of so-called conformational diseases such as Alzheimer's disease or prion diseases. In these pathologies, proteins or fragments lose their structure and then assemble themselves into ordered fibers within aggregates. The molecular mechanisms of the conformational changes of a protein and its polymerization into amyloid fibers are still largely unknown. Understanding these mechanisms and diagnosis are closely related to the availability of an efficient analytical concept for the ex vivo monitoring of these phenomena.To address this problem, a microsystem has been developed for the detection and monitoring of polymerization of tau and Aß peptide, the main biomarkers of Alzheimer's disease. The microsensor is based on the propagation of acoustic high frequency waves that extract the rheological properties of the target environment. By measuring complex impedance of the biosensor, a dedicated signal processing allows the extraction of viscoelastic parameters (viscosity and elasticity). The study and development of this microsystem involve multidisciplinary expertise in instrumentation: development and design and modeling of biosensors, signal conditioning and solving associated inverse problems.First, the sensor has been optimized to improve its sensitivity and allow tracking of polymerization. Work on the feasibility of the system showed the ability to discriminate protein solutions of different concentrations. Since the purpose of the detection system is the simultaneous detection of different biomarkers responsible for Alzheimer's disease, a multi-electrode sensor for the detection of these different analytes has been developed. The optimization of the sensor, the microfabrication processes and chemical surface treatments are also developed in this work.
8

"Mathematics online and mathematics mobile - where is all this going?"

Butler, Douglas 15 February 2012 (has links) (PDF)
No description available.
9

從美國專利法析論非顯而易知性之相關爭議 / A study on non-obviousness controversies in view of American patent law

黃柏維, Huang, Po Wei Unknown Date (has links)
專利制度是知識經濟時代最為重要的一種智慧財產權形式,不但對於技術創新居功厥偉,在國際商業活動中也占有極具份量的地位。而在取得專利的三大要件中,以非顯而易知性(即我國進步性)最為棘手,蓋其本身屬於不確定之法律概念,而容有裁量空間。 非顯而易知性發軔於美國判例法,其後由實務主導其發展。在指標性案例KSR判決中,最高法院揭示了非顯而易知性的審查架構,以Graham四要件法則為根柢,並輔以顯可嘗試原則及彈性運用的TSM檢測法,整體而言KSR判決提高了非顯而易知性的適格門檻。在後KSR時代,CAFC在機械工業、醫藥品與生物科技等領域分別依不同程度適用KSR見解。2009年In re Kubin案確認KSR見解可適用於不可預測性較高之基因生技領域,近幾年來顯可嘗試原則也獲得高度重視。 相較而言,我國進步性審查主要依據智慧財產局所制定的專利審查基準,但行政審查常有過於直觀簡略之嫌;法院判決則在「發明所屬領域中具通常技術者之技術水準」與「該領域具通常技術者參酌先前技術所揭露之內容及申請時的通常知識,是否能所能輕易完成系爭申請發明之整體」此兩步驟的論證上較為欠缺,整體而言達成進步性結論之心證揭露程度不足,對於當事人有突襲性裁判之虞。 本研究基於上述觀察所得,對美國與我國關於非顯而易知性概念之認知與實踐進行比對,並分別就審查實務面與產業因應面提出微薄建議,以期借鏡美國法經驗使我國未來實務操作更趨完善。 / Patent system is one of the most important forms of intellectual property rights in the era of knowledge economy, not only indispensable for technological innovation, also of great influnce in the international business activities. Among the three requirements of patentability, “Non-obviousness” (ie, “Inventive Step” in Taiwan) is the most difficult to fulfill, due to the uncertainty of its legal concept and the room for discretion. Non-obviousness was carved out in the U.S. case law and continuously developed by the court rulings. In the benchmark case KSR v. Teleflex, the Supreme Court articulated that the examination framework of non-obviousness is based on Graham four factors, along with other principles like “Obvious to Try” and the TSM test in a more flexible way. In general, KSR lifted the eligibility threshold for non-obviousness. It has been applied in different degrees by the Court of Appeals for the Federal Circuit to various fields such as machinery industry, pharmaceuticals and biotechnology in the post-KSR era. Then it was recognized in 2009 In re Kubin case that the KSR opinion is applicable to the unpredictable field, gene biotechnology, for instance. Besides, the “Obvious to Try” principle has been gaining much attention in recent years. In comparison, both administrative and juducial examinations of inventive step in Taiwan are mainly based on the “Substantive examination guidelines for invention patent” issued by the Intellectual Property Office. However, the administrative review is often reckoned to be too intuitive and rough, and the court decisions are considered to be made with less expression on “the level of the PHOSITA” and “whether a PHOSITA with the reference to prior arts and common knowledge can complete the whole invention without difficulty.” In all, the lack of revealing the reasoning on the inventive step conclusion might expose the parties in danger of surprise judgements. Based on the above observations, this study compared the cognition and practice of non-obviousness both in the United States and in Taiwan, and as a result, presented some primary suggestions in light of the United States’ experience toward both the practice and industries, so that our inventive step examination practice in the future could be improved.
10

Solução tampão que mimetiza as características ácido-base do tampão SMP em resposta à acidez de solos brasileiros / A buffer solution that mimics the acid-base characteristics of the SMP buffer in resposnse to the acidity of brazilian soils

Toledo, Jaderson dos Anjos 21 February 2011 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In Brazil, the SMP buffer has been used since the 60's as the main method to estimate the potential acidity and/or the soil lime requirement. However, SMP contains pnitrophenol and potassium chromate, substances with high potential for environmental contamination and able to promote the development of methemoglobin and carcinomas in lab handlers as a result of continued exposure. This work aimed to develop a buffer solution free of hazardous substances which can mimic the acid-base characteristics of the SMP buffer, with the composition used in the states of RS and SC (SMP-RS/SC), in response to the acidity of Brazilian soils. To develop the new buffer, imidazole and 2-(Nmorpholino) ethanessulfonic acid monohydrate (MES) were used as substitutes for pnitrophenol and potassium chromate, respectively. The titration of the buffer SMP-RS/SC with HCl was carried out and these data were used as the starting point for the new buffer reproduce the potentiometric behavior of SMP-RS/SC buffer. To achieve this, multiparametric regression analysis was used, taking as adjustable parameters the pKa values and the concentrations of the components of the new buffer. The final composition for the new buffer, called Santa Maria buffer (TSM) was obtained with: 37.5 mM of triethanolamine; 17.3 mM of imidazole; 30.7 mM of MES; 20.7 mM of calcium acetate and 721 mM of calcium chloride; with initial pH adjusted to 7.5. For comparison between TSM and SMP-RS/SC, we utilized 42 soil samples collected in different physiographic regions of Brazil. Linear regression was performed with pH-SMP and pHTSM values, and also, between the lime requirement by SMP and TSM, reaching determination coefficient (R2) greater than 0.99 in both cases. The TSM had equivalent sensitivity to the SMP-RS/SC in differentiating the acidity degree of soils, and can be used replacing this, without the need for change in routine laboratory and interpretations already developed to estimate the potential acidity or need limestone of soil. At temperature from 22 to 27 °C, the TSM has a long shelf life and can be stored in plasticpolypropylene or glass containers protected from light, for a period of 120 to 150 days. The replacement of SMP-RS/SC buffer by TSM is a viable alternative for soil testing laboratories to avoid the generation of hazardous wastes and to reducing the health risks for the lab handlers. / No Brasil, o tampão SMP vem sendo utilizado desde a década de 60 como o principal método para a estimativa da acidez potencial e/ou da necessidade de calcário do solo. No entanto, em sua composição, a solução SMP apresenta p-nitrofenol e cromato de potássio, substâncias essas com elevado potencial de contaminação ambiental e capazes de promover o desenvolvimento de metahemoglobina e carcinomas aos seus manipuladores, como conseqüência da exposição continuada. Este trabalho teve como objetivo principal desenvolver uma solução tampão livre de substâncias tóxicas, capaz de mimetizar as características ácido-base do tampão SMP, na composição utilizada nos estados do RS e SC (SMP-RS/SC), em resposta à acidez de solos brasileiros. Para o desenvolvimento do novo tampão, utilizaram-se como substitutos ao p-nitrofenol e ao cromato de potássio, o imidazol e o ácido 2-(N-morfolino) etanossulfônico monohidratado (MES), respectivamente. Realizou-se a titulação do tampão SMP-RS/SC com HCl e esses dados de titulação foram utilizados como ponto de partida para que o novo tampão reproduzisse o comportamento potenciométrico do tampão SMP-RS/SC. Para tanto, empregou-se análise de regressão multiparamétrica, considerando como variáveis os valores de pKa e as concentrações dos componentes do novo tampão. A composição final para o novo tampão, denominado Tampão Santa Maria (TSM), foi obtida com: 37,5 mM de trietanolamina; 17,3 mM de imidazol; 30,7 mM de MES; 20,7 mM de acetato de cálcio e 721 mM de cloreto de cálcio; com pH inicial ajustado a 7,5. Para comparação entre o TSM e o SMP-RS/SC, utilizaram-se 42 amostras de solo oriundas de diferentes regiões fisiográficas do Brasil. Ajustou-se regressão linear entre os valores de pH-TSM e pH-SMP, e também, entre a recomendação de calcário por TSM e por SMP, alcançando-se coeficiente de determinação (R2) superior a 0,99 em ambos os casos. O TSM apresentou sensibilidade equivalente ao SMP-RS/SC na diferenciação do grau de acidez dos solos estudados, podendo ser utilizado em substituição a esse, sem a necessidade de alteração da rotina e das interpretações laboratoriais já desenvolvidas para a estimativa da acidez potencial ou necessidade de calcário do solo. À temperatura de 22 a 27 ºC, o TSM apresenta uma longa vida útil, podendo ser armazenado em recipiente de plástico-polipropileno ou vidro protegido da luz, por um período de 120 a 150 dias. A substituição do tampão SMP-RS/SC pelo TSM é uma alternativa viável para os laboratórios de análise de solo evitarem a geração de resíduos perigosos e reduzirem os riscos à saúde dos técnicos manipuladores.

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