Numerical characterization and experimental verification of an in-plane MEMS-actuator with thin-film aluminum heater

In this paper, a novel concept of a thermo-mechanical MEMS actuator using aluminum thin-film heaters on a thermal oxide for electrical insulation is presented. The actuator is part of an universal tensile testing platform for thermo-mechanical material characterization of one dimensional materials on a micro- and nano-scopic scale under different environmental conditions, as varying temperatures, pressure, moisture or even vacuum and is realised in BDRIE technology. It is shown, that the actuator concept fulfills the requirements for the use in a tensile loading stage along with heterogeneously integrated nanofunctional elements, following a specimen centered approach in line with bottom-up self-assembly processes. Simulation and experiment agree very well in the thermal and mechanical domain and allow subsequent optimisation of the actuator performance.     

Biomass energy in Vojvodina: Market conditions,environment and food security

In this study, the policy, market conditions and food security of biomass energy sources are assessed for supplying the future needs of Vojvodina. The Autonomous Province of Vojvodina is an autonomous province in Serbia, containing about 27% of its total population according to the 2002 Census. It is located in the northern part of the country, in the Pannonia plain, in southeastern Europe.Vojvodina is an energy-deficient province. Vojvodina also has a large potential for renewable energy, especially energy from biomass (biodiesel and bio-ethanol). The lack of knowledge about renewable energy technologies by most policy-makers, potential consumers, and energy firm managers has played against renewable energy developments. The environmental impacts of programs that encourage biofuel production, farmland land requirements and the impacts on food production are also discussed, considering the life cycle analysis (LCA) as a tool.It is concluded that the rise in the use of biofuels is inevitable and that international cooperation, regulations and certification mechanisms must be established regarding the use of land, the mitigation of environmental and social impacts caused by biofuel production. It is also mandatory to establish appropriate working conditions and decent remuneration for workers of the biofuels production chain.     

Cleaner bioprocesses for promoting zero-emission biofuels production in Vojvodina

In this study, the policy, market conditions and food security of biomass energy sources are assessed for supplying the future needs of Vojvodina. The Autonomous Province of Vojvodina is an autonomous province in Serbia, containing about 27% of its total population according to the 2002 Census. It is located in the northern part of the country, in the Pannonia plain, in southeastern Europe. Vojvodina is an energy-deficient province. The incentives to invest human and financial resources in the research and development of cleaner bioprocesses are high, considering the benefits which might be achieved in terms of environment protection and manufacturing costs. In the near and medium tenu, the development of bioprocesses for waste recycling and resource recovery might be one of the most viable options, considering much research work has already been done. In Vojvodina, there are technological solutions that biofuels produced in a closed cycle, so that the quantity of waste reduced to a minimum. These solutions include the stillage (remainder after distillation) used for fattening cattle, and cattle excrement to produce biogas and manure as fertilizer. The energy required for the production of bioethanol is obtained combustion lignocelullose residual waste from the production of basic raw materials starch, or biogas. Ash from the burned biomass returned to soil as a source of minerals for plants and replacement of mineral fertilizer. Such a closed cycle is economical for small farms in Vojvodina.     

Phytochemical Characterization of Veronica officinalis L., V. teucrium L. and V. orchidea Crantz from Romania and Their Antioxidant and Antimicrobial Properties

Aerial parts of Veronica species are used in Romanian traditional medicine for the treatment of various conditions like kidney diseases, cough, and catarrh, and are known for their wound-healing properties. In the present study, the phenolic and sterolic content and the antioxidant and antimicrobial activities of three Veronica species (Plantaginaceae), V. officinalis L., V. teucrium L. and V. orchidea Crantz, were studied. The identification and quantification of several phenolic compounds and phytosterols were performed using LC/MS techniques and the main components were p-coumaric acid, ferulic acid, luteoline, hispidulin and β-sitosterol. More than that, hispidulin, eupatorin and eupatilin were detected for the first time in the Veronica genus. Nevertheless, representatives of the Veronica genus were never investigated in terms of their phytosterol content. The antioxidant potential investigated by Trolox equivelents antioxidant capacity (TEAC) and EPR spectroscopy revealed that V. officinalis and V. orchidea extracts presented similar antioxidant capacities, whilst the values registered for V. teucrium extract are lower. Regarding the antimicrobial activity of the investigated species, Staphylococcus aureus, Listeria monocytogenes and Listeria ivanovii were the most sensitive strains with MIC values between 3.9 and 15.62 mg/mL. The results obtained by this study may serve to promote better use of representatives from the genus Veronica as antioxidant and antimicrobial agents.     

Situation and perspectives of waste biomass application as energy source in Serbia

The Autonomous Province of Vojvodina is an autonomous province in the Republic of Serbia. It is located in the northern part of the country, in the Pannonia plain. Vojvodina is an energy-deficient province. The average yearly quantity of the cellulose wastes in Vojvodina amounts to about 9 millions tons barely in the agriculture, and the same potential on the level of Serbia is estimated to almost 13 million tons. Only minor part of straw is utilized, and almost two-thirds are incinerated on fields owing to the problems during plowing under. The large sector in Serbia utilizes only about 15% of straw, while the individual one utilizes about 50% of straw and 20% of cornstalks. Environment pollutions, abandonment of the utilization of at least of one-third of the yield and extermination of the natural resources, primarily of humus, represent very adverse results of such procedures. Main problems with respect to the profitable usage of straw and other post-harvest residues are high expenses of their collection (collecting, balling or some other manner of compression), transportation from production- to the usage cites, as well as their handling and storaging. The agricultural production in Serbia should be based on the system of farms. For the efficient farming, it is obvious to organize life of producer and of his family immediately close to the production capacities. For the agriculture development, it is obvious to create a system of premiums, efficient crediting and the elaborated tax system that could create a basis for the certitude of work, confidence and constant growth of production, together with the mentioned and other measures. As the result of the activities oriented to substitution of the classical energents with energy obtained from biomass, farm that is in a higher degree energetically independent should be created. In such case, farms should apply the basic principles of the cleaner manufacturing, as an integral part of the concept of the sustainable development.     

Development of Decibel Stepped Attenuator for Automated Sound Level Meter Calibration

MAPAN - Parameter testing in the sound level meter calibration, such as frequency weighting and linearity, needs precise adjustment of sound level in the decibel (dB) unit. In the...     

Wettability and bonding quality of exterior coatings on jabon and sengon wood surfaces

Wettability and bonding quality of exterior coatings on fast-growing wood surfaces were studied. Samples of air-dried flat-grained (tangential surface) and edge-grained (radial surface) pattern of jabon (Anthocephalus cadamba) and sengon (Paraserianthes falcataria) woods were used. Before application of exterior coatings, the surfaces of the lumber samples were sanded. To provide wood surfaces with various degrees of roughness, abrasive papers of 120, 240, and 360 grits were used for the surface preparation. The wettability of two exterior coatings (water-based acrylic and oil-based alkyd varnishes) on the sanded wood surfaces was measured using a sessile drop contact angle method. The Shi and Gardner (S/G) model was used to evaluate and compare the wettability of the surface coatings on the wood. The sanded wood samples were coated with the two coatings (two layers each). Bonding quality of the coating layers was measured using a crosscut tape test method. Experimental results show that constant contact angle change rate (K value) of the S/G model decreased as the grit number of abrasive paper increased. This indicates that the wettability decreased as the roughness of the surface decreased (surface becomes smoother). There was no evidence of differences in wettability between tangential and radial wood surfaces. The oil-based alkyd coating generated better wettability compared to the water-based acrylic. The crosscut tests showed that the bonding quality of the coating films on both jabon and sengon wood decreased as the surface became smoother. The sengon wood compared to jabon wood provided better coating wettability and bonding quality. Wettability in terms of the K values was a good indication for determining the bonding quality of the two varnish layers.     

Concept of cleaner production in Vojvodina

The Autonomous Province of Vojvodina is an autonomous province in Serbia, containing about 27% of its total population according to the 2002 Census. It is located in the northern part of the country, in the Pannonia plain. The importance of sector of the environment protection becomes even larger and observable, especially with respect of the strategic determination of Government of the AP of Vojvodina, the Republic of Serbia on the association with the European economic area (EEA) and joining with the states – members of the European Union (EU). Restitution of the concept of the cleaner production (CP) significantly helps to companies and the responsible persons (especially in the domain of industry) to harmonize their business activities with law demands concerning the environment protection, as well as to improve their processes and the process sequences. This makes a starting base for the obtaining of the integrated license for the installations that are included in a list of installations that have to obtain an integrated licenses (some 250 installations), on the basis of the Law on the integrated prevention and control of pollution of Vojvodina, the Republic of Serbia, for which the dead point is the year 2015.     

As generations speak.

Generational dialogue refers to both shifts in relatedness between generations as well as how the otherness of predecessors and successors are negotiated internally. At various points in the life cycle, the need for generational dialogue is rekindled. As a new place within the generational cycle is inhabited, the individual contends with a novel version of the self and the influences that other generations, both older and younger, exert. Since each new generation's place needs to be claimed and not simply conferred, clashes within and between subjectivities are inevitable. Doubts about the self give rise to a “sorting out” process of which generational dialogue is a part. Clinical examples illustrate the unconscious search for generational dialogue and how it might be engendered or thwarted in analytic work. (PsycINFO Database Record (c) 2010 APA, all rights reserved)