Ultrasonic and Electrokinetic Remediation of Low Permeability Soil Contaminated with Persistent Organic Pollutants

Electrokinetics has emerged as a potential technique for in situ soil remediation and especially unique because of the ability to work in low permeability soil. In electrokinetic remediation, non-polar contaminants like most organic compounds are transported primarily by electroosmosis, thus the process is effective only if the contaminants are soluble in pore fluid. Therefore, enhancement is needed to improve mobility of these hydrophobic compounds, which tend to adsorb strongly to the soil. On the other hand, as a novel and rapidly growing science, the applications of ultrasound in environmental technology hold a promising future. Compared to conventional methods, ultrasonication can bring several benefits such as environmental friendliness (no toxic chemical are used or produced), low cost, and compact instrumentation. It also can be applied onsite. Ultrasonic energy applied into contaminated soils can increase desorption and mobilization of contaminants and porosity and permeability of soil through developing of cavitation. The research investigated the coupling effect of the combination of these two techniques, electrokinetics and ultrasonication, in persistent organic pollutant removal from contaminated low permeability clayey soil (with kaolin as a model medium). The preliminary study checked feasibility of ultrasonic treatment of kaolin highly contaminated by persistent organic pollutants (POPs). The laboratory experiments were conducted in various conditions (moisture, frequency, power, duration time, initial concentration) to examine the effects of these parameters on the treatment process. Experimental results showed that ultrasonication has a potential to remove POPs, although the removal efficiencies were not high with short duration time. The study also suggested intermittent ultrasonication over longer time as an effective means to increase the removal efficiencies. Then, experiments were conducted to compare the performances among electrokinetic process alone and electrokinetic processes combined with surfactant addition and mainly with ultrasonication, in designed cylinders (with filtercloth separating central part and electrolyte parts) and in open pans. Combined electrokinetic and ultrasonic treatment did prove positive coupling effect compared to each single process alone, though the level of enhancement is not very significant. The assistance of ultrasound in electrokinetic remediation can help reduce POPs from clayey soil by improving the mobility of hydrophobic organic compounds and degrading these contaminants through pyrolysis and oxidation. Ultrasonication also sustains higher current and increases electroosmotic flow. Initial contaminant concentration is an essential input parameter that can affect the removal effectiveness.

Vårt land af J. L. Runeberg

Kansinimeke: Vårt land ; Maamme ; Our Land ; Unser Land.

Vårt land af J. L. Runeberg

Nimiösivulla myös: jemte finsk och tysk öfversättning.

Charta öfver Åland : Del. C. T.

Tekijä: Christophorus Tärnström, 1711-1746, laivapastori, tutkimusmatkailija.

Accurata Utopiae tabula : das ist der neuentdeckten Schalck-Welt, oder des so offtbenannten, und doch nie erkannten Shlarraffenlandes neu erfundene lächerliche Land-Tabelle

Irtokartta

Special passcharta öfwer een deel af Österjöön begynnandes ifrån Elsnabben att utwysa Stockholms-Skärgården medh heela cousten intill Gefle, samt och den Finska Skärgården till Åbo jemwäl heela Åland

Julkaisussa: General hydrographisk chart-book öfwer Östersjön och Katte-Gatt till sin raetta figur och stoorleek

Special passcharta öfwer een deel aff Österjöön begynnandes ifrån Calmarsund intill Stockholm, innehållandes jemwäl öjarna Gottland och Öland

Julkaisussa: General hydrographisk chart-book öfwer Östersjön och Katte-Gatt till sin raetta figur och stoorleek

Verschiedene Prospecte der vornemsten Städten in Persien samt vorderst einer unsern dem Caspischen Meer, dem Russischen Reich zugehörig, gelegenen Stadt, zu mehrerem Liecht und Erleuterung der neu-verfertigten persianischen Land-Charten

Irtokartta

M. Martin Helwigs erste Land-Charte vom Herzogthum Schlesien : nebst einer Erklärung zu finden Bresslau in der Grassischen Buchdruckeren

Kartta kuuluu A. E. Nordenskiöldin kokoelmaan

The duality of tactical thought : a study of how Swedish land forces' commanders view tactics in irregular warfare

This is a sociological study of the views of officers in the Swedish Army and its Amphibious Forces on tactics in Irregular Warfare (IW), in particular, Counterinsurgency (COIN). IW comprises struggles, where the military weaker part uses an indirect approach with smaller units and integrates the civilian and military dimensions in a violence spectrum including subversion, terrorism, Guerrilla Warfare and infantry actions. IW is the main armed warfare style in insurgencies. COIN is the combined political, military, economic, social and legal actions in counter insurgencies. Data has been collected by means of interviews with almost all (n =43) officers, who were either commanding battalions or rifle and manoeuvre companies while undergoing training for general warfare and international operations. The main theoretical and methodological inspiration is the traditional one for research on social fields, inaugurated by the French sociologist Pierre Bourdieu. The statistical technique used is Multiple Correspondence Analysis. As a background and context base, an inquiry inspired by the Begriffsgechichte (Conceptual History) tradition explores the genesis and development of understandings of the term Irregular Warfare. The research question is outlined as; “how can contemporary Swedish military thought on tactics in Irregular Warfare be characterized using descriptive patterns, mapped in relation to background factors and normative standards? The most significant findings are that there are two main opposing notions separating the officers’ views on tactics in Irregular Warfare: (1) a focus on larger, combat oriented and collectively operating military units versus smaller and larger, more intelligence oriented and dispersed operating units, and (2) a focus on military tasks and kinetic effects versus military and civilian tasks as well as “soft” effects. The distribution of these views can be presented as a two-dimensional space structured by the two axes. This space represents four categories of tactics, partly diverging from normative military standards for Counterinsurgency. This social space of standpoints shows different structural tendencies for background factors of social and cultural character, particularly dominant concerning military backgrounds, international mission experiences and civilian education. Compared to military standards for Counterinsurgency, the two tactical types characterized by a Regular Warfare mind-set stands out as counter-normative. Signs of creative thought on military practice and theory, as well as a still persistent Regular Warfare doxa are apparent. Power struggles might thus develop, effecting the transformation to a broadened warfare culture with an enhanced focus also on Irregular Warfare. The result does not support research results arguing for a convergence of military thought in the European transformation of Armed Forces. The main argument goes beyond tactics and suggests sociological analysis on reciprocal effects regarding strategy, operational art, tactics as well as leadership, concerning the mind-set and preferences for Regular, Irregular and Hybrid Warfare.

Suomi "the Land of a Thousand Lakes": a short descriptive account of the Grand Duchy of Finland

Inneh. bl. a. en engelsk öfvers af Runebergs "Vårt land".

Åland, illustrerad landskapsbeskrifning

Med en karta och 16 illustrationer