When a jack-up foundation is installed on seabeds consisting of a sand layer overlying soft clay, potential for 'punch-through' failure exists. This happens due to an abrupt reduction in bearing resistance when the foundation punches a block of sand into the underlying soft clay in an uncontrolled manner. This can lead to a sudden large penetration that can cause temporary decommissioning and even toppling of the unit. This research has addressed this problem with the aim of developing a practical design method for the jack-up industry to assess potential punch-through hazards. This objective has been achieved with the successful development of a new conceptual model for predicting the peak penetration resistance and a consistent method for constructing a complete resistance profile of spudcan foundations penetrating through sand into the underlying clay. The analytical basis of the new conceptual model follows the approach for silo analysis, and takes into account the stress level and dilatant response of sand. It is therefore a significant improvement over the punching shear and load spread models recommended in the current industry guidelines SNAME (2002), which do not consider the strength properties of the sand. To provide relevant experimental data for the new model, an extensive series of 30 continuous penetration tests were performed using the UWA drum centrifuge. These experimental results were retrospectively simulated using finite element (FE) analysis, in order to back-calculate the stress-level dependent friction and dilation angles in the sand during peak penetration resistance. The back-analysis showed that larger values of peak resistance gave lower friction and dilation angles, which is consistent with gradual suppression of dilatancy under high confining stress. When compared to published results from visualisation experiments, the FE analysis showed a similar failure mechanism during peak resistance, where a frustum of sand was forced into the underlying clay, with the outer angle reflecting the dilation in the sand. This has formed the basis of the new conceptual model. The performance of the new model in predicting the experimental peak resistance was compared with other existing analytical methods. Additional experimental results, including those already in the literature, were incorporated in the comparative study. It was found that the new conceptual model generally gave a good prediction of the experimental values, while the prediction from SNAME (2002) was conservative, with the predicted values being about half the experimental results on average. It was also shown that the new model could be modified to predict the post-peak penetration resistance in the sand layer. Finally, an analytical method for predicting the resistance profiles in the underlying clay was devised based on new bearing capacity factors developed through FE analysis. By joining the values of peak resistance, post-peak resistance and the resistance profile in the underlying clay, a complete simplified penetration resistance profile for spudcan foundations in sand overlying clay can be generated. The predicted profiles were shown to match the experimental results well.

No description available.

A purificação do biodiesel originado do processo de produção por transesterificação de óleos e gorduras requer a remoção de resíduos de glicerina. Como metodologia de cálculos correlações que dão origem a diagramas de dimensionamento foram transformados em modelos matemáticos envolvendo importantes números adimensionais. Apresenta-se uma estratégia de separação da glicerina dispersa no biodiesel utilizando um hidrociclone otimizado da família Rietema. Foram simuladas e analisadas as condições de separação da mistura biodiesel-glicerina, etapa integrante do processo de produção desse biocombustível por transesterificação de óleos e gorduras, em condições operacionais otimizadas e não otimizadas. A estratégia de otimização foi o uso de correlações econômicas e geométricas, as quais levaram à obtenção de um custo mínimo. Uma das etapas mais importante do processo de produção de biodiesel é a de sua purificação. Um hidrociclone do tipo convencional foi proposto para a referida etapa. A estratégia usada para elaboração da função objetivo foi composta de três termos: custo de aquisição, custo de operação e o custo associado a não coleta do biodiesel, todas como função do diâmetro do equipamento. Como programas de cálculos para dimensionamento e otimização foram utilizadas a planilha eletrônica Excel e sua ferramenta solver. Os resultados mostraram que a estratégia e otimização forneceram valores de dimensionamento muito próximos dos de condição não otimizadas, demonstrando que a mesma pode ser utilizada como reforço, numa época em que os critérios econômicos são importantes justificativas de investimentos nas melhorias dos processos produtivos / The purification of biodiesel of the production process by transesterification of oils and fats require the removal of glycerin waste. It presents a strategy for separation of glycerin dispersed in biodiesel using an optimized hydrocyclone of the Rietema family. As calculation methodology correlations that lead to the sizing diagrams were converted into mathematical models involving significant dimensionless numbers. It presents a strategy for separation of glycerin dispersed in biodiesel using an optimized hydrocyclone of the Rietema family. They had been simulated and analyzed the conditions of separation of the mixture biodiesel-glycerin, integrant stage of the process of production of this biofuel of separation of oils and fats, in optimized and not optimized operational conditions. The optimization strategy was the use of economic and geometric correlations, which had led to the attainment of a minimum cost. One of the stages most important of the process of production of biodiesel is of its purification. One hidrociclone of the conventional type was considered for the related stage. The used strategy for elaboration of the objective function was composed of three terms: cost of acquisition, cost of operation and the associated cost does not collect of biodiesel, all as function of the diameter of the equipment. As programs of calculations for sizing and optimization the electronic spread sheet Excel and its tool had been used to solve. The results had shown that the strategy and optimization had supplied values of not optimized sizing very next to the ones of condition, demonstrating that the same one can be used as reinforcement, at a time where the economic criteria are important justifications of investments in the improvements of the productive processes

Submitted by EDER RENATO SAVAZZI null (edersavazzi@hotmail.com) on 2017-09-21T18:11:30Z No. of bitstreams: 1 SAVAZZI, E. R. Sustentabilidade e Otimização Energética de uma planta industrial .pdf: 10486715 bytes, checksum: c5f7f12a7e3167bc3b4a4449aacfcfa3 (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-09-26T17:54:15Z (GMT) No. of bitstreams: 1 savazzi_er_me_guara.pdf: 10486715 bytes, checksum: c5f7f12a7e3167bc3b4a4449aacfcfa3 (MD5) / Made available in DSpace on 2017-09-26T17:54:15Z (GMT). No. of bitstreams: 1 savazzi_er_me_guara.pdf: 10486715 bytes, checksum: c5f7f12a7e3167bc3b4a4449aacfcfa3 (MD5) Previous issue date: 2017-08-01 / O emprego de centrífugas tipo batelada numa usina sucroalcooleira é feito a partir de dados disponibilizados pelos fabricantes dos equipamentos, em função, basicamente, da capacidade produtiva de cada máquina e da sua eficiência energética. Grande parte das unidades sucroalcoleiras em atividade no país ainda operam com máquinas antigas, de pequeno porte, com baixa eficiência energética, com acionamento por motores multi-polos comandados por contatores para variação da velocidade. Até a década passada as usinas produtoras de açúcar e etanol geravam energia apenas o suficiente para seu auto consumo; com os incentivos do governo federal através de programas como o Proinfa, as usinas foram motivadas a comercializar seu excedente de energia para o SIN, possibilitando o aumento de suas receitas. Pelo fato de produzir sua própria energia através da queima do bagaço, praticamente não havia preocupação com os equipamentos de baixa eficiência energética que operavam nestas plantas, porém, a partir da possibilidade da comercialização do excedente de energia foi necessário um trabalho para melhorar o desempenho energético dos equipamentos de maior consumo. Deste modo, a proposta deste trabalho consiste na análise comparativa da substituição de centrífugas antigas por centrífugas modernas (considerando o dimensionamento adequado em função do processo e dos limites operacionais de cada máquina), com foco tanto nos resultados técnicos, quanto produtivos e financeiros do investimento. As centrífugas propostas possuem motor de alto rendimento acionados por inversor de frequência regenerativo, que possibilita a geração de energia pela própria máquina durante a etapa de desacelaração e, como se trata de um processo cíclico, a devolução de energia para a rede é feita repetidamente a cada ciclo. O modelo de otimização proposto foi validado a partir de dados de aplicações em empreendimentos existentes, com resultados compatíveis com o que foi efetivamente implantado; seu pay-back tem a capacidade de pagar a implantação de uma nova máquina por ano, apenas com o retorno financeiro do ganho com energia elétrica. / The use of batch centrifuges in a sugar mills is based on data provided by the equipment manufacturers, basically due to the production capacity of each machine and its energy efficiency. Most of the sugar-alcohol units in operation in the country still operate with old machines, small, with low energy efficiency, driven by multi-pole motors driven by contactors for speed variation. Until the past decade, sugar and ethanol-only plants that produced only enough energy for their own consumption, with the federal government's incentives through programs like Proinfa, the mills were motivated to market their surplus energy to SIN. Thus enabling an increase in its revenue. Because it produced its own energy through the burning of the bagasse, there was practically no concern with the low energy efficiency equipment that operated in these plants, from the possibility of the commercialization of surplus energy, a work was needed to improve the energy performance of the equipment Consumption. Thus, the proposal of this work consists of the comparative analysis of the replacement of old centrifuges by modern centrifuges (considering the adequate design depending on the process and the operational limits of each machine), focusing both on technical and productive and financial investment results. The proposed centrifuges have high efficiency motor driven by a regenerative frequency inverter, which allows the generation of energy by the machine itself during the deceleration stage and as it is a cyclic process the return of energy to the network is done repeatedly every cycle. The proposed optimization model was validated from application data in existing projects, with results compatible with what was effectively implemented, the pay-back has ability to pay for the deployment of a new machine per year, only with the financial return of the gain in electric power.

Submitted by (edna.saturno@ufrpe.br) on 2016-06-13T13:41:47Z No. of bitstreams: 1 Cibele Cavalcanti Souza de Melo.pdf: 1262965 bytes, checksum: a0b751f71b7ca0dbc7f0a215b3c2b60f (MD5) / Made available in DSpace on 2016-06-13T13:41:47Z (GMT). No. of bitstreams: 1 Cibele Cavalcanti Souza de Melo.pdf: 1262965 bytes, checksum: a0b751f71b7ca0dbc7f0a215b3c2b60f (MD5) Previous issue date: 2015-02-27 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The aim was to evaluate the effect of the Aloe vera gel (Aloe barbadensis Miller), in association with the Tris base (hydroxymethyl aminomethane) or powdered coconut water (ACP- 106®) in canine semen conservation, as well as the action of this gel in the renewal process of the extender. Semen samples from five dogs, of breed Basset Hound, were used. In Experiment 1, samples were diluted in duplicate, using Tris plus 20% egg yolk (G1 and G2) or 5% Aloe vera (G3 and G4) and evaluated at 0, 48, 72 and 96 hours. After 48 hours, all samples were centrifuged for 10 minutes (400g) in a cooled centrifuge (5 °C). In the groups G1 and G3 the supernatant was removed and a new extender was added. In the other groups (G2 and G4) pellets were re-diluted in the same supernatant, without renewal. For Experiment 2, samples were divided into two equal aliquots, according to the treatments (G1: Tris + 20% egg yolk, control G2: Tris + 5% Aloe vera; G3: ACP-106® + 5% Aloe vera) and evaluated at 0, 24, 48 and 72 hours after cooling. In both experiments were performed sperm kinetics and membrane integrity analysis (iMP). In Experiment 1 results the diluent renewal did not affect on any parameter analyzed in the group using egg yolk (G1), shown when comparing the two treatments of this substance. The G2 (without renewal) did not demonstrate a significant difference when compared to G1 (renewal). However, groups with Tris-Aloe vera (G3 and G4) were lower (P <0.05) than the groups with Tris-egg yolk (G1 and G2) after the renewal, and this has showed deleterious effect on the group that sperm received new diluent (G3) in all parameters. There were no statistical differences in Experiment 2 in the parameters of total motility, straightness and oscillation index and plasma membrane integrity comparing treatments and evaluation times. However, the progressive motility in G1 proved to be significantly higher (P <0.05) than the other treatments in the first assessment period (0h). However, at 24 the G3 showed values similar to G1. The linearity values of G3 were significantly higher (P <0.05) than other groups from the start of the evaluations. According to the findings from Experiment 1, it can be concluded that the replacement of diluent is not necessary for the preservation of canine spermatozoa undergo cooling (5 °C) for 96 h. Furthermore, it was found that the gel of Aloe vera may be used to replace egg yolk in dog semen cooling diluent at a concentration of 5% without renewal. In the Experiment 2, it can be concluded that Aloe vera can be used at a concentration of 5% to replace egg yolk in dog semen cooling diluent, regardless of the one used. / Objetivou-se avaliar o efeito do gel da planta Aloe vera (Aloe barbadensis Miller), associado ao diluidor Tris (hidroximetil aminometano) ou Água de coco em pó (ACP-106®) na conservação de sêmen de cães, bem como a ação desse gel no processo de renovação do diluidor. Foram utilizadas amostras seminais de cinco cães da raça Basset Hound. No Experimento 1, as amostras foram diluídas em duplicata, utilizando Tris + 20% de gema de ovo (G1 e G2) ou 5% de Aloe vera (G3 e G4), e avaliadas nos tempos de 0, 48, 72 e 96 horas. Após a análise de 48h, todas as amostras foram centrifugadas por 10 min (400g) em centrífuga refrigerada (5 ºC). Nos grupos G1 e G3 o sobrenadante foi removido e um novo diluidor foi adicionado. Nos outros grupos (G2 e G4) os pellets foram re-diluídos no mesmo sobrenadante, sem renovação. Para o Experimento 2, as amostras foram divididas em alíquotas iguais, de acordo com os tratamentos (G1: Tris + 20% gema de ovo, controle; G2: Tris + 5% Aloe vera; G3: ACP-106® + 5% Aloe vera) e avaliados nos tempos de 0, 24, 48 e 72 horas após refrigeração. Em ambos experimentos foram realizadas análises de cinética espermática e de integridade da membrana (iMP). Nos resultados do Experimento 1 a renovação do diluidor não influenciou em nenhum parâmetro analisado no grupo que utilizou gema de ovo (G1), fato evidenciado quando comparados os dois tratamentos que utilizaram esta substância. O G2 (sem renovação) não determinou diferença significativa quando comparado ao G1 (com renovação). Entretanto, os grupos com Tris-Aloe vera (G3 e G4) foram inferiores (P<0,05) aos grupos com Tris-gema de ovo (G1 e G2) após a renovação, e esta mostrou efeito deletério nos espermatozoides do grupo que recebeu novo diluidor (G3), em todos os parâmetros. No Experimento 2 não foram encontradas diferenças estatísticas nos parâmetros de motilidade total, retilinearidade e índice de oscilação e integridade de membrana plasmática quando comparados os tratamentos e os tempos de avaliação. Entretanto, a motilidade progressiva no G1 mostrou-se significativamente superior (P<0,05) aos demais tratamentos no primeiro tempo de avaliação (0h). No entanto, às 24h o G3 demonstrou valores semelhantes ao G1. Os valores de linearidade no G3 foram significativamente superiores (P<0,05) aos demais grupos desde o início das avaliações. De acordo com os achados do Experimento 1, pode-se concluir que a renovação do diluidor não é necessária para a preservação dos espermatozoides caninos submetidos à refrigeração (5 ºC) por 96 h. Além disso, constatou-se que o gel da Aloe vera pode ser utilizado em substituição à gema de ovo, no diluidor de refrigeração de sêmen de cães, na concentração de 5%, sem renovação do diluidor. Já no Experimento 2, pode-se concluir que a Aloe vera pode ser empregada na concentração de 5% em substituição à gema de ovo no diluidor de refrigeração de sêmen de cães, independente do diluidor utilizado.

A centrifugação é o principal método utilizado para fracionar o Sangue Total (ST) nos componentes sanguíneos: Concentrados de Hemácias (CH), Concentrados Plaquetas (CP), Plasma e Crioprecipitado, (também chamados de Hemocomponentes). Com intuito de prevenir ou controlar hemorragias, os CP obtidos por centrifugação tornaram-se o padrão no atendimento inicial aos pacientes com baixas contagens de plaquetas. Porém, para obter uma unidade terapêutica (UT), no Hemocentro RP, é necessário agregar seis CP, formando o Pool de CPST (PCP), o que leva a exposição do receptor a vários doadores diferentes. O CP obtido por aférese (CPAF), advindo de equipamento que permite a seleção já na coleta, fornece a dose necessária em apenas uma doação. Baseado no levantamento de dados internos do Hemocentro de RP o presente estudo analisou, através da metodologia de Custeio Baseado em Atividade (ABC), os custos atribuídos às distintas metodologias para a produção dos CP, sabendo que no Hemocentro RP, os CP são dispensados como UT independente da forma de obtenção. Os resultados obtidos foram utilizados na Análise de Custo-Efetividade, evidenciando que a coleta por Centrifugação de ST com a produção de PCP foi mais custo efetiva em 2015 do que a coleta de aférese, porém, por uma diferença relativamente pequena, devido ao grande percentual de obtenção de dupla Unidade Terapêutica (CPAF2). / Centrifugation is the main method used for fractionating Total Blood (TB) to blood components: Red Cells Concentrate (CR), Platelet Concentrates (PC), Plasma and Cryoprecipitate (also called Hemocomponents). In order to prevent or control bleeding, CPs obtained by centrifugation became the standard treatment of patients with low platelet counts. However, to obtain a therapeutic unit (TU), at Hemocentro RP, it is necessary to get together six PCs, forming a Pool of TBPC (PCP), exposing the receptor to several different donors. PC obtained by apheresis (CPAF), which is provided by a equipment that allows selective collection, achieve the dose necessary for the selection in just one donation. Based on the collection of internal data from the Hemocentro RP, the present study analyzed, through the methodology of ActivityBased Costing (ABC), the costs attributed to the different methodologies for the production of PCs knowing that in the Hemocenter RP PCs are dispensed as TU independent of the way of obtaining. The results obtained were used in the CostEffectiveness Analysis, showing collecting by TB Centrifugation producing PC is more cost-effective, however CPAF was almost as effective as in 2015, a great achievement of Dual Therapeutic Unit in a single donation (CPAF2).

Orientador: Ricardo de Lima Isaac / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-18T11:03:55Z (GMT). No. of bitstreams: 1 Haak_Wando_M.pdf: 4830827 bytes, checksum: 311caf27f5b5da6d03f6312ef08d15bc (MD5) Previous issue date: 2011 / Resumo: Estações de tratamento de água (ETA) geram resíduos durante o processo de potabilização da água bruta. Esse resíduo onera as companhias de saneamento, no que tange o tratamento e disposição final. O tratamento do lodo é constituído de processos de separação sólido-líquido, cuja eficiência - quanto à maximização do teor de sólidos da torta (lodo desaguado) e melhor qualidade da água recuperada no processo - é dependente do adequado condicionamento químico, em geral obtido pela ação de polímeros. A super- dosagem ou a sub-dosagem desse produto ocasiona perda de qualidade, tanto da torta, quanto da água eliminada. Este trabalho tem como objetivo verificar através de estudo de bancada, a viabilidade técnica e econômica do condicionamento químico na adequação de processo de tratamento de lodo de ETA, visando melhor desempenho na fase de desaguamento, tendo em vista a disposição final dos resíduos gerados durante o tratamento. Foram relacionadas medidas de potencial redox com controle de dosagem e consumo de polímero catiônico de alto e muito alto peso molecular, de baixa, média e alta densidade de carga e polímero aniônico de alto peso molecular, com baixa e média densidade de carga, com e sem oxidação química com cloro e permanganato de potássio. Na investigação experimental os resultados referentes ao tempo de filtração, indicaram os polímeros catiônicos de alto peso molecular, de baixa e média e alta carga como sendo mais eficientes. Para valores de potencial redox entre -57mV e 75mV, os polímeros catiônicos, em sua maioria, apresentaram consumos de 6,0 a 10,0 (kg/tms), em lodo não oxidado. A oxidação do lodo com permanganato de potássio ou cloro para valores entre -11mV e +11mV foi significativa, com redução da dosagem de polímeros catiônicos para valores de 4,0 a 7,0 (kg/tms), proporcionando economia de 30%. Considerando-se as correlações encontradas, tendo em mãos, sondas confiáveis de pH e potencial redox, é possível automatizar um determinado sistema de dosagem para oxidação do lodo / Abstract: Water treatment plants (WTP) generate waste during the process of potabilization of raw water. This residue burdens the sanitation companies, with regard to treatment and final disposal. The sludge treatment process consists of solid-liquid separation, whose efficiency - as to maximize the solids cake (dewatered sludge) and better quality of the reclaimed water in the process - is dependent on proper chemical conditioning, usually obtained by action of polymers. Over dosage or under dosage of those products causes loss of quality of both, cake and eliminated water. The aim of this work is to verify the technical and economical feasibility of the chemical conditioning at the fitting of sludge treatment process at a WTP, through work bench study, aiming at better performance during the dewatering, looking at the treatment final discharge of residues. Measures of redox-controlled dispensing were related to consumption of cationic polymer of high and very high molecular weight, of low, medium and high charge density and anionic polymer of high molecular weight, of low and medium charge density, with and without chemical oxidation with chlorine and potassium permanganate. At the primary investigation of percolating time, the cationic polymers of high molecular weight with low, medium and high charge, proved to be more efficient. For potential redox values between -57mV and 75mV, most of the cationic polymers consumed from 6.0 to 10.0 (kg/tms), in non-oxidized sludge. There was a significant oxidation of sludge with potassium permanganate or chlorine for values between -11 and +11mV, reducing the dosage of cationic polymers to values from 4.0 to 7.0 (kg/tms), providing a 30% economy. Taking into account the correlations found, using reliable pH and redox potential probes, it is possible to automate a system of dosage for the sludge oxidation / Mestrado / Saneamento e Ambiente / Mestre em Engenharia Civil

Preanalytiska faktorer såsom provhantering och förvaring utgör den vanligaste felkällan inom laboratoriemedicin, vilket tyder på bristande kunskap kring faktorer som påverkar provers stabilitet. ALAT, ASAT och bilirubin är markörer för utvärdering och behandling inom leverdiagnostik, varpå tillförlitliga provsvar är av stor vikt.Syfte: Att granska tidigare studier och göra en sammanställning av stabiliteten för ALAT, ASAT och bilirubin vid olika typer av förvaring innan och efter centrifugering, olika centrifuginställningar, samt i rör med olika tillsatser.Metod: En allmän litteraturstudie gjordes genom systematisk sökning och bearbetning av vetenskapliga artiklar relaterade till syftet.Resultat: Studierna om analytstabilitet hos centrifugerade prover hade en stor spridning mellan resultaten som kan förklaras av studiernas olika upplägg, främst med tanke på att de pågick under olika lång tid. Gällande jämförelse av provrör skiljde det som mest fem dagar mellan PST och Barricor-rör i en av studierna. Studierna om centrifugering visade inte på någon skillnad i stabilitet med de inställningar av centrifugalkraft och tid som användes.Slutsats: Bristen på studier med liknande studiedesign gör det svårt att dra några säkra slutsatser kring stabiliteten vid olika förvaring. Resultatet antyder att varken olika rörtillsatser, centrifuginställningar eller fördröjd centrifugering upp till 24 timmar påverkar stabiliteten för ALAT, ASAT eller bilirubin. / Preanalytical factors such as specimen handling are the most common source of error in laboratory medicine, suggesting a lack of knowledge about factors affecting sample stability. ALAT, ASAT and bilirubin are markers that underlie evaluation and treatment in liver diagnostics, therefore reliable test answers are of great importance.Objective: To review previous studies and compile the stability of ALAT, ASAT and bilirubin for different storage before and after centrifugation, different centrifuge settings, and in tubes with different additives.Method: A literature review was done through systematic search and processing of scientific articles related to the objective.Results: The studies on analyte stability of centrifuged samples showed great variance between the results, mainly due to the studies lasting for different lengths of time. One study comparing test tubes showed a five day difference for ASAT between PST and Barricor tubes. Centrifugation studies showed no difference in stability with the centrifugal settings used.Conclusion: The lack of studies with similar study designs makes it difficult to draw any certain conclusions about the stability in different storage conditions. The result suggests that neither different tube additives, centrifuge settings nor delayed centrifugation up to 24 hours affect the stability of ALAT, ASAT or bilirubin.

Activated Partial Thromboplastin Time (APTT) is a screening method used to detect defects in the intrinsic pathway. Different preanalytical variables such as centrifugation and thawing can affect the given test results from APTT analysis. The purpose of the study was to evaluate how the results for APTT were affected when frozen citrate plasma was thawed in a heating cabinet or a water bath, and how the results for APTT were affected if the samples were single or double centrifuged before freezing. A total of 40 fresh samples were collected for each study purpose and analyzed. To study how thawing conditions affected frozen samples, aliquoted plasma was frozen at –20°C for a week and then thawed in either a water bath or in a heating cabinet. To study how single and double centrifugation affected the test results, one of the two aliquots per sample was centrifuged again while the other remained single centrifuged. The samples were then stored frozen for one week and afterwards thawed. The results showed statistically significant differences between fresh samples and frozen samples thawed in a heath incubator or water bath. Regarding centrifugation conditions, both single and double centrifugation yielded statistically significant differences in comparison to fresh plasma. All the evaluated sample treatments showed statistically significant differences in comparison to fresh samples. However, in all cases the mean percentage change was ≤10%, which indicates no clinical significance. In conclusion APTT-samples seem to be sensitive to preanalytical variables and further studies are needed to evaluate their effects.

No / Spheric and anisotropic gold nanoparticles (GNPs) such as rods, stars or nanoprism prepared using hexadecyltrimethyl ammonium bromide (CTAB) as the stabilising agent have received a great deal of interest in the last years. The literature procedures exploited lead to GNPs in aqueous solution. We herein describe a fast, efficient, and cheap method to transfer particles of different shapes from water into toluene solution via ligand exchange (CTAB to dodecanethiol), which was mediated by acetone as a cosolvent. Absorption spectra and TEM-pictures before and after the transfer revealed that the particles survived the transfer intact and without change in shape.