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Katjonu apmaiņa mālu minerālos atkarībā no sērskābes šķīduma iedarbības ilguma = Cation Exchange from Clay Minerals by Sulfuric Acide Treatment Continuance
No full textA Broader Look on Sustainable Development
No full textIf we are looking back to the history of Earth in the scale of million years, we can see that there was always development but newer sustainability. New species appeared and lot of them disappeared. History span of Homo Sapience is only about hundred thousands of years. However, humans are very different animals: they make things and this is a new factor in the Earth development. Humans invented tools, technology, economy, and society totally different from animal social order. Humans have consciousness and one of the most crucial questions for them is - what will be the future of Homo Sapience?
Growth of populations tends to be exponential. After that there are two possible scenarios. They are - collapse of population due to the lack of available resources or transition to the stable equilibrium state. Reverend Maltus (1798) was first to detect this law of Nature. It seems that there is still mainly exponential growth of human population with quite a lot of decreases due to plagues, natural cataclysms, and wars.
Growth simulation by the Club of Rome (1972) clearly demonstrated that we are rapidly approaching the point where natural resources will be exhausted. The world community tried to find solutions to this problem.
The term “Sustainable Development” was coined year 1987 by Bruntland’s commission.
It is rather controversial term – in fact it is contradictio in adjecto.
According with the Second Law of Thermodynamics - entropy increases for any closed system; in other words, each time a system goes through a thermodynamic process (e.g. DEVELOPMENT), the system can never completely return to precisely the same state it was in before, e.g., it can not be SUSTAINABLE. Strictly speaking, Earth is not a closed system. But only energy inflow comes from the Sun. This energy has made atmosphere, water resources, and huge amounts of fossil energy (which we are now rapidly wasting) in the period of billion years.
According with the definition, the Sustainable Development is a “development that meets the needs of the present without compromising the ability of future generations to meet their own needs”.
According with popular scheme, there are three components of sustainability – Nature, Economy, and Society. “Green movement” is mainly focusing attention on the environmental issues – Nature in narrow sense. Sure, we must care about our Mother the Nature. However, the driving forces of development and sustainability now are economy and social consciousness of human species. To ensure sustainability we must concentrate on these factors and adapt them accordingly. Experience of the last decades has shown that existing model of economy can not guarantee sustainability. Natural resources are exhausted exponentially. Wealth distribution between regions and between the citizens of the individual states is becoming more and more uneven; which will lead to unrest and conflicts. These tendencies can lead to the cataclysms and extinction of human species.
There is a new factor – Artificial Intelligence (AI). Consequences of this factor on human society development until now are rather neglected and not much contemplated. In near future, possibly in this century, humankind will face a new challenge – human made AI with the power above Human Intelligence. It can be used for the benefit of humans, it can be used against the part of humans, but if it will be intelligence, then AI will be able to take there own decisions. At the time being we are not ready to meet this situation and are ignoring consequences of this line of Development
Mikroelementu saturs Latvijas mālos pirms un pēc apstrādes ar skābi
No full textMālus apstrādājām ar 10% un 25% sērskābes šķīdumiem. Ar skābi apstrādātos mālu paraugos samazinās Th, Y, Cu un Zn saturs. Pb saturs nemainās – tas varētu atrasties tādos minerālos, kuri nepakļaujas skābes iedarbībai, vai arī tāpēc, ka PbSO4 ir nešķīstošs (uz šo īpatnību jāattiecina visi nešķīstošie metālu sulfāti). Nelielais Zr daudzums norāda uz cirkona klātbūtni mālos, bet Nb un Sn klātbūtne var būt kā izomorfā aizvietošanās cirkonā. To apstiprina tas, ka pēc Liepas un Kupravas mālu apstrādāšanas ar skābēm šo elementu saturs nemainās
Adsorbcija uz māliem un ar skābi apstrādātiem mālu paraugiem = Adsorption on Clays and Samples Made by Treating Clays with Acids
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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Latvijas mālu sorbtīvās īpašības un to palielināšana, apstrādājot mālus ar skābes šķīdumiem
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