Selected exploitation problems of agricultural vehicles in the scope of their servicing

Jedną z przyczyn uszkodzeń pojazdów i maszyn rolniczych jest ich niewłaściwa obsługa z zakresu wymiany i stosowania materiałów eksploatacyjnych. Podstawowymi błędami popełnianymi podczas eksploatacji maszyn rolniczych są: niezachowanie terminu wymian oleju silnikowego, zastępowanie oleju napędowego olejem opałowym, wykorzystywanie wody w układzie chłodzenia w zastępstwie płynu chłodzącego oraz brak właściwej obsługi roboczych i napędowych układów hydraulicznych. Celem artykułu jest przedstawienie zależności między błędnie wykonanymi czynnościami obsługowymi a stanem maszyn rolniczych.One of the reasons of damages of agricultural machines is inappropriate operation in the range of exchange and usage of operating materials. Common defects during operation of agricultural machines are: not keeping the date of engine oil exchange; replacing diesel oil with fuel oil, replacing cooling fluid with water in the cooling system; lack of appropriate operation of working and driving hydraulic systems. The purpose of this article is to present relations between inappropriate operating actions and the condition of agricultural machines

Electromagnetic emission of digital circuits implemented in Xilinx FPGAs XC 4025E and XCV 800

The results of testing electromagnetic emissions generated by circuits implemented in Xilinx FPGAs XC 4025E and XCV 800 types are presented. Both radiated and conducted emissions of the circuits were measured as a function of cIock frequency. Possible practical recommendations are discussed

A comparison of efficiency of secondary metabolites extraction/leaching techniques from carnivorous plants dry material from in vitro culture

W roślinach owadożernych za efekt terapeutyczny odpowiadają głównie pochodne 1,4-naftochinonu (juglon) oraz flawonoidy. Ze względu na interesujące właściwości tych związków oraz możliwość synergicznego działania wielu innych metabolitów wtórnych na efekt terapeutyczny, podjęto pracę przygotowania technologii efektywnego wyodrębniania tych związków z tkanek roślinnych. W publikacji porównano efektywność różnych technik ekstrakcji i ługowania. Jako materiał badany posłużyły wysuszone i rozdrobnione rośliny owodożerne z rodziny Droseraceae: Dionaea muscipula, bogata w pochodną 1,4-naftochinonu-plumbaginę oraz Drosera aliciae, bogata w ramentaceon. Zbadany został wpływ temperatury na efektywność ekstrakcji/ługowania. Wykazano, że zastosowane, nowoczesnej techniki ekstrakcji – ługowania pozwala na skrócenie czasu przygotowania wsadu do rozdzielania, bez utraty zawartości metabolitów w ekstraktach – ługach, w stosunku do stosowania technik i warunków tradycyjnych. Jednocześnie, w przypadku nietrwałych termicznie metabolitów wtórnych, krótki czas operacji i możliwość jej wykonywania w stosunkowo niskiej temperaturze, zapewnia wyższy stopień ekstrakcji/ ługowania, niż stosowanie tradycyjnych technik i warunków. Otrzymane wyniki stanowią podstawę do opracowania technologii pozyskiwania w sposób ciągły, ekstraktów/ługów bogatych w metabolity roślinne lub grzybowe, a także składniki tkanek zwierzęcych, na większą skalę, do przemysłowej, włącznie.Plants from the Droseraceae family are interesting because of the secondary metabolites profile that results from their way of nutrition. The use of carnivorous plants in medical treatment was first mentioned in the 12th century. It was applied to heal human air passages infections. This therapeutical effect is caused by secondary metabolites. The most widely known are 1,4-naphtoquinones (for expample: plumbagin, ramentaceone), which have antibacterial and anticancer activity. It is caused by the ability to generate Reactive Oxygen, inhibition of topoisomerase, and inactivation of DNA. Moreover, carnivorous plants contain flavonoids (quercetin and myricetin) , which are stronger antioxidants than vit. C and E. Furthermore, in our research material we found more than 20 different, already identified and unrecognized metabolites. This variety of discovered substances could potentially indicate a synergic therapeutic effect. This study was conducted to develop the most efficient procedure to isolate metabolites from plants or fungi using Droseraceae as an example of plants contained very important metabolites and in relative high concentration. The conclusions from this research should be valid also for extraction/leaching of metabolites from other plants. The following extraction/leaching techniques were compared: Soxhlet extraction in Soxtec® device, Microwave assisted extraction (MAE), Ultrawave assisted extraction (UAE), homogenization in a high-shear mixer and maceration with stirring. The influence of time and temperature was investigated, in order to find optimal conditions for each operation. As an experiment material plants from Droseracae species were used: Dionaea musicpula and Drosera aliciae - which are riched in 1,4-naphtoquinones: plumbagin or ramentaceone. It was concluded that modern extraction/leaching techniques using ultrawaves or microwaves are less time-consuming without causing any additional metabolites loss in comparison to traditional methods. Additionally, for metabolites with low thermal stability, shorter operation time is more preferable. It have been also concluded on the basis of our study, that some of searched operations can be relative simple apply for an industrial scale and continuous operation

Lessons Learned from WiMAX Deployment at INEA

Home broadband access is continuously demanding more bandwidth fueled by video streaming, entertainment and gaming applications. In 2010, a company INEA decided to roll-out new WiMAX-based services aimed to meet the needs of home users across theWielkopolska region of western Poland. It was decided to follow the 802.16e standard and the Time Division Duplexing (TDD) mode that oer the ability to adjust the downlink/uplink ratio and thus are well suited for data transmission. After an extensive testing period of equipment from various vendors, engineers at INEA have chosen the Motorola (currently Cambium Networks) PMP320 solution because it is compact and its components are space- and energy-ecient. The company choice was also influenced by its simple operation, management and installation, which ensured low costs of ownership. So far, this deployment has provided fast and aordable connectivity for Internet and telephony services to around 5,500 households across the 30,000 sq. km region. After 3 years of experience, INEA would like to share the lessons learned from this roll-out