Characterisation of properties of coniferous wood tracheids by x-ray diffraction, laser scattering and microscopy

In recent years there has been growing interest in selecting suitable wood raw material to increase end product quality and to increase the efficiency of industrial processes. Genetic background and growing conditions are known to affect properties of growing trees, but only a few parameters reflecting wood quality, such as volume and density can be measured on an industrial scale. Therefore research on cellular level structures of trees grown in different conditions is needed to increase understanding of the growth process of trees leading to desired wood properties. In this work the cellular and cell wall structures of wood were studied. Parameters, such as the mean microfibril angle (MFA), the spiral grain angles, the fibre length, the tracheid cell wall thickness and the cross-sectional shape of the tracheid, were determined as a function of distance from the pith towards the bark and mutual dependencies of these parameters were discussed. Samples from fast-grown trees, which belong to a same clone, grown in fertile soil and also from fertilised trees were measured. It was found that in fast-grown trees the mean MFA decreased more gradually from the pith to the bark than in reference stems. In fast-grown samples cells were shorter, more thin-walled and their cross-sections were rounder than in slower-grown reference trees. Increased growth rate was found to cause an increase in spiral grain variation both within and between annual rings. Furthermore, methods for determination of the mean MFA using x-ray diffraction were evaluated. Several experimental arrangements including the synchrotron radiation based microdiffraction were compared. For evaluation of the data analysis procedures a general form for diffraction conditions in terms of angles describing the fibre orientation and the shape of the cell was derived. The effects of these parameters on the obtained microfibril angles were discussed. The use of symmetrical transmission geometry and tangentially cut samples gave the most reliable MFA values.

Zum Stellenwert von Fischmehl in der Aquakultur

The worldwide aquaculture production amounts to about one third of the world fishery catch. While the world fishery catch in the last years is stagnating and an increase is not to be expected, the aquaculture rose by about 10 % annually. This rate of growth is also predicted for the next years. Fish meal and oil forms a key position for the further development of aquaculture, specially for carnivorous fish species, of which the salmonids will gain an increasing economic importance, not only on the European, but also on the Japanese and American markets. Without an adequate supply of fish meal and oil for the production of these fish species, the expected product quality cannot be realized under economic conditions. Fish meal and oil are commonly produced from small pelagic fish species, which, at present and in the near future, have no importance for direct human consumption. Since December2000 the use of fish meal and oil in Germany is only allowed for use in aquaculture and petfood. However, conclusive arguments for a ban on the utilization for other animal feeds do not exist so far. The European Union continues to allows feeding of other animals – except ruminants – with fish meal under certain control measures.

Macroeconomía y medio ambiente: El PIB como medida de bienestar

Este Trabajo de Fin de Grado estudia el uso del Producto Interior Bruto (PIB) como medida de bienestar. Al tiempo que se realiza el análisis de la contabilidad nacional y, en mayor profundidad del PIB, se detallan algunas medidas alternativas. Éstas han surgido como consecuencia de la búsqueda de indicadores que incluyan en sus mediciones, no solo el crecimiento económico, sino también otra serie de variables que son relevantes y que el PIB no contempla (como los recursos naturales, la contaminación, la calidad de vida o la igualdad en la distribución de la renta de un país, por ejemplo). Así, surgen nuevos indicadores como el PIB ambientalmente ajustado, el Índice de Mejor Vida, el Índice de Progreso Genuino o la Huella Ecológica, entre otros. Como resultado de este análisis se concluye que la medida que mejor refleja el bienestar depende del objetivo específico que se busque investigar. En otras palabras, hoy en día ninguna medida es capaz de contestar todas las preguntas relacionadas con el bienestar de la población. Sin embargo, el PIB no está configurado –ni fue creado- como una medida de bienestar de un país. Por lo tanto, actualmente es preciso acompañar la información de este indicador con la de otros alternativos de tal manera que podamos tener una imagen más completa sobre el nivel de bienestar de un país.

Estudo de adsorção de ácidos naftênicos a partir de correntes de hidrocarbonetos

Ácidos naftênicos correspondem à complexa mistura de ácidos carboxílicos presentes no petróleo, responsáveis diretamente pela sua acidez e pela sua corrosividade em fase líquida durante o refino. Tais compostos também estão presentes nas frações destiladas do petróleo, causando diversos problemas na qualidade final do produto. Uma possível forma de remover esses ácidos das frações destiladas é através da adsorção em materiais porosos. Contudo, os resultados até então apresentados indicam que resinas trocadoras de íons seriam os melhores adsorventes destes compostos, o que poderia aumentar o custo do processo e diminuir sua viabilidade. Neste trabalho, dois adsorventes comerciais (argila e alumina ativada) foram caracterizados por diversas técnicas físico-químicas e avaliados quanto à sua capacidade de remover os ácidos naftênicos de frações médias e pesadas de petróleo. Avaliou-se, ainda, para fins de comparação, o comportamento de ácidos naftênicos comerciais em óleos sintéticos preparados com óleo mineral. Em complementação, a corrosividade do aço carbono nos meios estudados foi também verificada. A argila apresentou maior afinidade com os ácidos naftênicos, tendo capacidade de adsorção superior e cinética de processo ligeiramente mais rápida às da alumina para as cargas sintéticas. No entanto, em virtude da maior concorrência pelos sítios de adsorção, apresentada pelos outros componentes presentes em óleos reais, observou-se uma perda na eficiência para estas amostras. Neste caso, a alumina apresentou melhores resultados. Embora ambos adsorventes tenham apresentado boa capacidade de remoção do soluto, a resina trocadora de íons ainda apresentou resultado mais eficaz para as amostras reais. Nas condições desse estudo, a taxa de corrosão do aço nas amostras sintéticas e em duas das reais não foi significativa e apenas uma delas apresentou-se corrosiva (Óleo 1). No entanto, a remoção dos ácidos naftênicos por adsorção conseguiu reduzir a taxa de corrosão neste meio em até 99%

Validação de métodos analíticos - estudos de casos relevantes de atividades dos laboratórios de controle de qualidade de vacinas

A validação dos métodos de análises em situações fora da rotina, em P&D pesquisa e desenvolvimento, pode tornar-se um processo de difícil solução, em oposição àquelas de rotina, onde as concentrações são conhecidas. Nesta última situação, o método analítico é validado e aprovado com simplicidade. Apesar dos elementos de qualidade básicos para análises em P&D serem os mesmos adotados nas análises de rotina, fatores como o comportamento imprevisível da amostra, a composição desconhecida da matriz e interdependência com o analito, mesmo a incerteza a respeito da escolha do método instrumental, requer uma atenção renovada nos elementos de qualidade existentes. A razão pode ser atribuída à imprevisibilidade do procedimento analítico e a extensão do esforço adicional dos elementos de qualidade. As incertezas das análises em P&D requerem uma cuidadosa consideração do problema, assim como a disponibilidade de técnicas analíticas. Ao mesmo tempo, devem-se observar o planejamento e organização do trabalho, a supervisão do desenvolvimento analítico e a adequação dos aspectos técnico e organizacional - no trabalho de P&D, a definição de responsabilidades e a competência do corpo técnico. A garantia da qualidade nas indústrias farmacêuticas é estabelecida pelo desenvolvimento de especificações apropriadas para matérias-primas, produtos intermediários e produtos finais. A importância de especificações adequadas foi estabelecida e exemplos foram dados no desenvolvimento de especificação típica para produtos farmacêuticos, tais como a vacina e matéria prima. Isto incluiu uma discussão dos tipos de parâmetros que precisam ser controlados e uma indicação dos valores numéricos ou faixas esperadas para muitos materiais utilizados. A metrologia analítica que necessita ser aplicada para demonstrar a observância com as especificações foi discutida, com as implicações de desempenho do método para diferenciar variações na qualidade do produto e a simples variabilidade analítica. Esse trabalho foi escrito para laboratórios, com a finalidade de dar um suporte na implementação da validação de métodos analíticos e introduzir o conceito de incerteza da medida nas análises de rotina. O objetivo foi fornecer de uma maneira compreensível e prática a metodologia dos cálculos das medidas de incerteza baseados principalmente em dados de controle de qualidade e de validação já existentes. Exemplos práticos retirados diretamente do Laboratório de Metrologia e Validação, FIOCRUZ / Bio-Manguinhos, foram apresentados. Entretanto, o tratamento usado neste trabalho é genérico e pode ser aplicável a outros laboratórios químicos

Bericht über vergleichende Untersuchungen zur Lagerung von Fischfilet in konventionellen und mit Silbernanopartikeln beaufschlagten Verpackungen

Kurzfassung Die Lebensmittelbranche erwartet durch den Einsatz von Nanotechnologien hervorragende Fortschritte bei der Verbesserung der Produktqualität und der Lebensmittelsicherheit. Vor diesem Hintergrund wurde 2009 am Max Rubner Institut der Fach- und Institutsübergreifende Forschungsschwerpunkt „Nanotechnologie“ etabliert, um Grundlagen zu erarbeiten, aufgrund derer die Auswirkungen der Nanotechnologie auf Lebensmittel und damit die Ernährung und Gesundheit der Verbraucher beurteilt werden können. In diesem Forschungsprojekt wurde der Einfluss neuer, mit Nanopartikeln beaufschlagter Verpackungsfolien auf Fischfilet untersucht. Abstract: The food industry expects by the application of nanotechnology excellent progress in the improvement of the product quality and the food safety. On this background the Max Rubner Institute established in 2009 an interdisciplinary focus on nanotecchnology research to formulate principles upon which the impact of nanotechnology on food and thus the nutrition and health of consumers can be assessed. In this research, the impact of new, nanoparticles containing packaging films was examined for fish fillet.

Shelf life of dried products from small indigenous fish species under various packing and storage conditions

The overall quality of five SIS products was found in good condition up to 2 months storage on the basis of organoleptic, biochemical and bacteriological characteristics and all the products was excellent in sealed packed condition up to 45 days of storage. However, quality of the products stored in open air atmospheric temperature was found excellent for first 15 days. In an average the initial moisture content was in the range of 13.5 to 15.0% with highest moisture content in puti and lowest in chapila. At the end of the 60 days the moisture content reached to the range of 18.5 to 19.0% which was more or less near the recommended limit of 16% for dried fishery products. The moisture content beyond the recommended limit as the storage period increased further and at the end of 90 days the moisture content increased to the range of 22.9 to 24% when organoleptically the product quality became very poor. The changes in the value of total volatile base nitrogen (TVB-N), peroxide value (PO), moisture and aerobic plate count (APC) of solar tunnel dried products in sealed polythene packages were investigated during 60 days of storage. There was little or no differences in TVB-N, PO and bacterial load of each species packed under various polythene density. The initial TVB-N values were in the range of 10.30 to 12.40 mg/100g of the samples. TVB-N value increased slowly up to the end of the storage period and was to in the range of 46.20 to 57.00 mg/1 00 g of sample. Initially the peroxide values (P.O.) were in the range of 6.54 to 8.40 m.eq./kg oil of the samples. During 60 days of storage, P.O. values increased slowly and at the end of the storage period these values reached to the range of 22.00 to 25.30meq./kg of sample. The initial APC was in the range 5.3xl04-7.3x104 CFU/g. The bacterial load increased slowly and at the end of the 60 days storage period reached to the range 6.6x106 - 8.6x107 CFT/g.

An assessment of handling and processing methods used for the shrimp fishery by-catch in Kalpitiya, Sri Lanka

The by-catch from the shrimp trawl fishery in Kalpitiya is mainly used for the production of dried fish, which provides an additional source of income for fishermen in the area. It has been observed that current handling practices along the value addition chain are responsible for the poor quality and low price of the end product. This study was aimed at identifying the shortcomings in such handling practices by fishermen and dried fish producers and assessing the quality of shrimp fishery by-catch along the processing chain in order to recommend more efficient utilization methods that will improve the quality of the end product. Fresh fish, dried fish and harbour water samples were tested for total coli forms, faecal coliforms, E. coli and Salmonella in order to assess their microbial quality: In addition, standard plate counts (SPC) of fish samples were also carried out. A survey was carried out from July-October 2006 at Kalpitiya, using a pre-tested questionnaire to collect information from individuals who have been engaged in dried fish processing. Average values obtained for freshly landed and dried fish respectively, were, SPC 9.88x10 super(5) CFU/g and 30.43x10 super(5) CFU/g, total coliforms 23.05 and 24.23 MPN/g and fecal coliforms 8.28 and 9.00 MPN/g. These values exceed the recommendations in the SL standards. A quarter of the landed fresh fish and 38% of dried fish from the producers were positive for E. coli and thus failed to show required end product quality. SPC of harbour water was 14.35x10 super(6) CFU/ml and all samples were found to be contaminated with E. coli. None of the fishermen and dried fish producers were satisfied with the quality of the end product. The reasons for poor quality as indicated by them were: limited availability of ice (75%), lack of infrastructure facilities (65%), uncertainty of markets (52%), lack of emphasis on quality (47%) and poor access to available technologies (41%). Respondents to the questionnaire also identified: unavailability of potable water, insulated boxes, good landing jetty, racks for drying fish, poor cold storage facilities and limitations in dried fish storage facilities, as further factors leading to the loss of quality in their products. Results demonstrate that improvements to the infrastructure facilities and conducting of proper awareness programmes on handling practices could lead for improvements in the quality of value added products prepared from the shrimp fishery by-catch at Kalpitiya.

Data-based robust multiobjective optimization of interconnected processes: energy efficiency case study in papermaking.

Reducing energy consumption is a major challenge for "energy-intensive" industries such as papermaking. A commercially viable energy saving solution is to employ data-based optimization techniques to obtain a set of "optimized" operational settings that satisfy certain performance indices. The difficulties of this are: 1) the problems of this type are inherently multicriteria in the sense that improving one performance index might result in compromising the other important measures; 2) practical systems often exhibit unknown complex dynamics and several interconnections which make the modeling task difficult; and 3) as the models are acquired from the existing historical data, they are valid only locally and extrapolations incorporate risk of increasing process variability. To overcome these difficulties, this paper presents a new decision support system for robust multiobjective optimization of interconnected processes. The plant is first divided into serially connected units to model the process, product quality, energy consumption, and corresponding uncertainty measures. Then multiobjective gradient descent algorithm is used to solve the problem in line with user's preference information. Finally, the optimization results are visualized for analysis and decision making. In practice, if further iterations of the optimization algorithm are considered, validity of the local models must be checked prior to proceeding to further iterations. The method is implemented by a MATLAB-based interactive tool DataExplorer supporting a range of data analysis, modeling, and multiobjective optimization techniques. The proposed approach was tested in two U.K.-based commercial paper mills where the aim was reducing steam consumption and increasing productivity while maintaining the product quality by optimization of vacuum pressures in forming and press sections. The experimental results demonstrate the effectiveness of the method.

Data-based robust multiobjective optimization of interconnected processes: Energy efficiency case study in papermaking

Reducing energy consumption is a major challenge for energy-intensive industries such as papermaking. A commercially viable energy saving solution is to employ data-based optimization techniques to obtain a set of optimized operational settings that satisfy certain performance indices. The difficulties of this are: 1) the problems of this type are inherently multicriteria in the sense that improving one performance index might result in compromising the other important measures; 2) practical systems often exhibit unknown complex dynamics and several interconnections which make the modeling task difficult; and 3) as the models are acquired from the existing historical data, they are valid only locally and extrapolations incorporate risk of increasing process variability. To overcome these difficulties, this paper presents a new decision support system for robust multiobjective optimization of interconnected processes. The plant is first divided into serially connected units to model the process, product quality, energy consumption, and corresponding uncertainty measures. Then multiobjective gradient descent algorithm is used to solve the problem in line with user's preference information. Finally, the optimization results are visualized for analysis and decision making. In practice, if further iterations of the optimization algorithm are considered, validity of the local models must be checked prior to proceeding to further iterations. The method is implemented by a MATLAB-based interactive tool DataExplorer supporting a range of data analysis, modeling, and multiobjective optimization techniques. The proposed approach was tested in two U.K.-based commercial paper mills where the aim was reducing steam consumption and increasing productivity while maintaining the product quality by optimization of vacuum pressures in forming and press sections. The experimental results demonstrate the effectiveness of the method. © 2006 IEEE.

中国北方海域扇贝产品质量的比较研究

由于局部养殖环境质量恶化和病害频发的困扰，严重影响了我国扇贝养殖产量、质量和出口创汇。针对扇贝养殖面临产品质量不高等问题，系统评估我国扇贝产品质量十分必要。本文以我国北方海域海湾扇贝Argopecten irradians和栉孔扇贝Chlamys farreri为研究对象，较为系统地研究了大连湾、秦皇岛、莱州湾、烟台、威海、胶州湾、胶南等七海域扇贝质量，包括营养品质、重金属富集、麻痹性贝毒污染三个方面。 研究结果表明，栉孔扇贝的蛋白质营养优于海湾扇贝，而脂类营养则低于海湾扇贝，海湾扇贝在不同海域的主成分分析可以看出，地理位置接近的海域营养状况比较相似，各海域的综合营养品质依次为：莱州湾＞烟台＞大连湾＞秦皇岛＞威海＞胶州湾＞胶南； 重金属含量存在组织差异性，贝边的含量总是高于贝柱，取自同一海域的栉孔扇贝的重金属含量高于海湾扇贝，六种重金属的平均含量排序为：Zn＞Cu＞Cd＞As＞Pb＞Hg，部分海域扇贝Cd和Zn有超标现象，两种重金属分别超标1.41～17.28倍和1.24～1.59倍，Hg、Pb、As和Cu均未超标； 用小白鼠生物测试法对扇贝内脏团、贝柱和其他组织的贝毒含量进行测定，结果仅在秦皇岛和大连湾海湾扇贝的内脏团中检测出麻痹性贝毒，其毒力分别为2.17 Mu•g -1和2.48 Mu•g -1，未超过食用安全标准（4 Mu•g -1），其他海域的样品均未检测到麻痹性贝毒的存在。

甲壳单糖、寡糖、低聚糖制备方法的优化与比较研究

该文通过大量实验,确定了制备单糖、寡糖及低聚糖的最佳生产工艺,并对几种制备方法做了比较研究.该文采用氧化降解和微波降解等不同技术对甲壳低聚糖的制备工艺进行了研究.H<,2>O<,2>作为氧化剂,在酸性条件下,采用4因素3水平进行正交实验,得到了制备分子量2000以下的寡糖的最佳条件.微波降解制备低聚糖目前尚未见报道,经过该实验证明此方法可降低能耗,减小污染,节省时间和原料,是一个具有产业化前景和市场潜力的好方法.通过以不同的壳聚糖为原料,探讨了在微波场作用下纯溶剂及盐效应对分子量变化的影响,最终产物的分子量均在1×10<'5>～10×10<'5>之间.根据IR光谱,壳聚糖降解前后主要峰的位置都无变化,只是随壳聚糖相对分子质量的降低各峰峰强有所变化,证明了壳聚糖氧化降解及微波降解制备寡糖、低聚糖是以开裂壳聚糖的β-1.4糖苷键来进行.该项研究对更好的开发利用甲壳质资源,促进中国海洋生物制品的发展具有十分重要的意义.

对螺钉无轴向压力的高精度自动螺丝刀的设计

区别于现有的电动、气动螺丝刀工具,该螺丝刀系统在驱动螺丝时,能对螺钉头实现无轴向压力的调节。刀头在旋转的同时随螺钉轴向进给,转速与进给量匹配,保证刀头与螺钉不脱节。该系统调整精度高,刀头转动精度可达0.72°,其应用于断路器类低压电气产品的自动调试,对确保产品质量、提高生产效率具有积极意义。

冷轧MES机组作业计划过程中的任务分配法

基于鞍钢新轧集团股份有限公司冷轧薄板厂MES工程的实际情况,介绍了机组排产作业计划过程中的任务分配方法。该方法以机组与生产任务的最佳匹配、机组的负荷平衡为性能指标,采用了实时最小负荷分配规则,科学地解决了冷轧生产线CIMS环境下机组排产作业计划的在线生成问题,实现了生产线上的生产路径优化控制,从而提高了生产质量和设备利用率。

企业经营风险决策的组织行为学研究

This thesis has investigated the risk preferences of the Chinese company managers in kinds of simulated decision situations and their perceptions of risk concerning types of business decisions. Four studies are conducted: Study I is utility analysis. 214 company managers and 46 middle - school headmasters have responded to Utility Measurement Survey. The results indicate: (1) The risk preferences of the managers vary in the different decision situations. In most of the situations, most of the managers are risk aversion; In few situations, they are risk-seeking. (2) In some of the decision situations, there are significant differences on risk preference between business managers and school headmasters, male managers and female managers, senior managers and junior managers, managers with high qualifications and managers with low qualifications, non-state-owned firms' managers and state-owned firms' managers, medium-small sized firms' managers and large-sized firms' managers. In the other situations there aren't significant differences between them. (3) In all of the decision situations, so significant differences on risk preference are found among managers with different marriage, experience, age and education. Study II is risky decision simulation. The Risky Decision Situations Simulation Survey is administered to 82 company managers. The result indicates that firm culture, business condition, survival limit and risk preference of the superior influence the managers' risk decision-making behavior. Study III is perceptions of business decision risks. 68 company managers have filled in Decision Cases Risk Perception Inventory. The results indicate: (1) Inaccurate market analysis and prediction, instable politics and the changes of economic policy are the more risky elements to strategy decision. (2) Erroneous market analysis and prediction, appearance of new technology and the changes of market demands are the more risky elements to investment decision. (3) Poor quality control, backward technology and too large stocks are the more risky elements to production decision. (4) Shortage of development fund, wrong choice in development project and limitation of the development ability are the more risky elements to new production development decision. (5) No payment of the foreign partner's capital, the changes of national relevant policy, difficulty in marketing, too high selling prices of foreign partner's equipments are the more risky elements to joint-venture decision. (6) Unfamilarity with oneself and misjudgement in qualification of oneself are the more risky elements to personnel decision. (7) Bad market of the product, defects in product quality and the changes of consumers demands are the more risky elements to marketing decision. (8) Wrong strategy and ambiguous goals are the more risky elements to public relation decision. (9) Violation of the law, ambiguous goals and poor creation are the more risky elements to advertisement decision. (10) Deterioration of diplomatic relations, unsuitable products for foreign consumers and unfamilarity with foreign market are the more risky elements to international business decision. Study IV is structured interview. 5 company managers have answered all questions of the Interview Questionnaire. The results indicate: (1) The managers think that risks are the possible unfavourable consequences of decisions; (2) The self-ratings of the managers coordinate with the results of utility measurement; (3) The managers admit that risks always accompany bussiness decision; (4) Individual difference is found among managers on risk perception. This thesis has also pointed out the important implications of the research and discussed several further questions.