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Nitrogen removal in constructed wetlands of vertical and horizontal flow
2006
Gasiunas, V. | Strusevicius, Z.
Constructed wetlands (CW) are considered as one of principal wastewater treatment methods containing and soil filters. CW may be of subsurface vertical flow (VF) and horizontal flow (HF). The objective of the studies was to estimate N-removal efficiency differences in CW of vertical and horizontal flow. To evaluate nitrogen (N) removal efficiency, the database of the studies on both construction of CW collected within the period of 1995-2005 was used. Horizontal filter systems characterize for a 1.6 times higher N-removal efficiency than vertical filters. Generally, N-removal efficiency depends on the load of filters. When filter load was 1.5 g mE-2dE-1 according to TN, N-removal efficiency is 39.6 and 24.0% in HF and VF systems respectively. Considering the seasons of the year, no significant difference was observed in N-removal efficiency in HF and VF systems during cold and warm periods of the year. N contained in water after the treatment process in filters is detected in different forms. NH4-N is prevailing in HF, while in VF systems NO3-N is dominant. It was also observed that NH4-N in the effluent during the initial operation of VF after the construction works in the first two months in the warm and in four months during their operation in the cold period of the year was prevailing.
Показать больше [+] Меньше [-]Treatment of wastewater in milk collecting station
2006
Askinis, S.
The paper presents the test results of studies on the treatment of wastewater in experimental treatment facilities in a milk collecting station. The treatment process of wastewater was a follows: aeration-flocculation device -sedimentation pond - two-stage constructed wetlands. The laboratory investigations have shown that the primary treatment with quicklime (1 kg mE-3) reduces wastewater pollution by 54%, while the treatment with coagulant 'ZETAG 8660' (4 g mE-3) reduces it by even 68%. Such results were not obtained in the primary wastewater treatment stage under industrial conditions: biological oxygen demand (BOD5) in wastewater was reduced 27.2%, the amount of suspended sediment was reduced by 48.1%, the amounts of Ntotal and Ptotal decreased by 15.8% and 27% respectively. Such results much depended on the air temperature, inaccurate dosage of chemicals as well as on insufficient capacity of reaction and sedimentation reservoirs for 2.5 times higher amount of wastewater. However, despite such unfavourable conditions, this stage of treatment process was rather efficient: the pollution of wastewater with organic matter flowing into the stream did not exceed the maximum allowable rates. The average value according to BOD5 was 4 mg O2 lE-1, the highest BOD5 value was 9.6 mg O2 lE-1. From the environment protection point of view, it is particularly important that the removal of biogenic pollutants is quite sufficient in the wastewater treatment facilities. After the treatment process in wastewater treatment facilities, the amount of Ntotal decreased by 82.4% and the amount of Ptotal was reduced by even 97.3%.
Показать больше [+] Меньше [-]Development of agricultural information system in Lithuania
2006
Raupeliene, A. | Perkumiene, D.
Analysis of statistical reports provided by the Statistical Department of Lithuania shows that a rapidly increasing number of agricultural enterprises are using computers for the preparation of documents and processing of accounts, and the internet for sourcing information and sending correspondence to business partners and other institutions. There is also a steady increase in the number of a-services, such as transference of payments, which are available via the internet. To identify the needs of agricultural specialists and rural citizens for e-services, a survey of available on-line services and potentially necessary e-services was carried out in August 2004. On the basis of these responses, the e-services of most importance to agricultural institutions and rural citizens now and in the near future were identified. These results also could be useful for other newly-joined EU countries of central and Eastern Europe.
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2006
Abolina, I.
The research work of current paper is dedicated to the problems that appear in resource attraction processes of the Cohesion Fund (CF) in Latvia. Latvia has an access to branches of financing covered by CF - transport and environment. These branches require harmonized legislation. Successful administrating is assured by effective institutional system. The weaknesses of CF management system in Latvia are figured out so rendering ideas to the reader to be studied further.
Показать больше [+] Меньше [-]Intrazonal agricultural resources in Kurzeme peninsula
2006
Silina, L.
The paper focuses on the exposition of the research results on agricultural resources in Kurzeme peninsula-climatic resources, qualitative evaluation of the land, condition of land amelioration, topographic resources, and structural breakdown of farm land by types of use. It is concluded that extremely various climatic and soil conditions govern in the region. The Southeast part of Kurzeme peninsula is displayed very favourably by the aggregate value of agricultural resources. Labour productivity in Kurzeme has been analysed as well.
Показать больше [+] Меньше [-]Methodological attitudes of the research of employee motivation
2006
Marcinkeviciute, L. | Zukovskis, J.
The article is meant to analyze the methodological qualitative characteristics of the creation of employees' motivation. These characteristics help to measure the reliability of research instruments. In accordance with Kendal ranking correlation (Henning, 1997) there are identified motivation indicators of managing employees and executives. The main attention is paid to the importance of motivation models' shaping and the essential principles by giving the results of model shaping and their interpretations.
Показать больше [+] Меньше [-]Society, social capital and social nets
2006
Igaune, E.
The scientific article is prepared using monographic research method. The most important works by several scientists are examined. The author analyses guidelines for strengthening of civil society within Decree of 2005 by the Cabinet of Latvia; previous research on social capital in scientists' works is considered and indicators regarding economics of Latvia are characterized; formal and informal social networks and their norms are cleared. Importance of civil society is suggested by the Cabinet Decree No. 98 Guidelines of Strengthening Policy for Civil Society in 2005. The guidelines and directions for strengthening of civil society for the ten years describe actuality of this program. This theme is less researched in Latvia. Civil society promotes democracy, increases and mobilizes social capital, coordinating collaboration of citizens for common benefit. Civil society in Latvia is in its initial position. The concept of social capital by different foreign scientists and Latvian specialists is analysed in this article. American scientist R. Putnam (1995) has written about social capital that human capital regards individuals but social capital regards relationships among individuals as well as social networks and exchange norms. Another researcher F. Fukuyama (1995) analyses social capital by comparison of economical development of different peoples and nations. Research by several scientists on indicators of social capital and their use in economics of Latvia are analysed in the work. The author concludes that social capital of Latvia has tendency to develop, and social networks and their expansion is little explored in Latvia.
Показать больше [+] Меньше [-]Peculiarities of water and waste utilities regulatory systems in the Vidzeme region and the world
2006
Gabrane, I.
Currently public services become more and more significant in procurement of daily activities of each inhabitant and the entire society. Therefore optimal solutions of the regulatory issues are the topic of the day. Objective of the article is to analyse regulatory systems of the provision of water and waste water utilities in Latvia and in other countries, to draw conclusions derived from the analyses and put forward suggestions for the choice of the most appropriate regulatory system in the local governments of Latvia. The hypotheses advanced in the study have proved that each country may use its own discretion when selecting the regulatory system for water and waste water utilities.
Показать больше [+] Меньше [-]Influence of hydrolysed oats insoluble fraction on dough quality
2006
Gramatina, I. | Kreicbergs, V.
The major wheat flour constituent, which determines the dough quality, is gluten. Oatmeal has higher biological value due to amino acid composition and content if compared to other cereals, but the technological properties of proteins are not as good as the ones of wheat flour. Oat products can be used in bread making although the increased amount of additives shows negative influence on bread texture, elasticity, volume, taste, and flavour. The method is developed for hydrolysed oatmeal separation in soluble and insoluble fractions, thus extending the oatmeal application possibilities. The aim of the current research was the investigation of influence of hydrolysed oats insoluble fraction on wheat dough rheological properties. The obtained results proved that in case hydrolysed oats insoluble fraction additive was used, water adsorption was increased by 63.8%-66.4% and dough stability time was changed from 4.8 to 10.0 min. The negative influence on dough development time and dough softening degree was observed. The farinograpgh quality index was within acceptable limits (less than 120 FU), if the oat additive of 10% and 15% was used. It is possible to obtain dough with better rheological properties if the hydrolysed oats insoluble fraction additive is 15% from flour mass.
Показать больше [+] Меньше [-]Fortified wheat grains with microelement selenium
2006
Duma, M. | Karklina, D.
Selenium (Se) is an essential microelement for human health; it is not synthesized in human body and cannot be substituted by any other element. Many health problems have a link with Se deficiency. People need to obtain all necessary amounts of selenium with food. Cereal products are important components of our diets and can contribute comparatively large part of the total dietary intake of Se. The wheat grains growing in Latvia contain comparatively small amount of selenium - on average 0.04 mg kgE-1. The objective of this study was to investigate the possibilities of fortifying wheat grains with microelement selenium during soaking grains in selenium containing solutions. Wheat grain was soaked in sodium selenite and sodium selenate solutions with selenium concentration from 10 to 200 mg lE-1. Sprouting activity was determined after 24, 72 and 120 hours, the influence of selenium valence in compound was observed. Comparing the influence of Se**+4 and Se**+6, it can be concluded that Se**+4 does not promote sprouting activity of wheat grains position to Se**+6 which increases sprouting activity till selenium concentration 100 mg lE-1. Uptake of selenium in grains was studied by determination of total Se using atomic absorption spectroscopy method. Linear correlation between Se concentrations in applied soaking solutions and Se concentration in grains was observed. The content of total protein did not change significantly - it varied from 13.64% in the control sample to 13.87% in the wheat sample with the highest applied selenium concentration (200 mg lE-1).
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