Search results for "Climate"
showing 10 items of 4934 documents
Identifying Iron-Bearing Nanoparticle Precursor for Thermal Transformation into the Highly Active Hematite Photo-Fenton Catalyst
2020
Funding: This reseach was funded by the European Regional Development Fund within the Activity 1.1.1.2 “Post-doctoral Research Aid” of the Specific Aid Objective 1.1.1 “To increase the research and innovative capacity of scientific institutions of Latvia and the ability to attract external financing, investing in human resources and infrastructure” of the Operational Programme “Growth and Employment” (No. 1.1.1.2/VIAA/1/16/157).
Organic matter and wettability characteristics of wildfire ash from Mediterranean conifer forests
2015
Abstract Thermogravimetric analysis (TGA) and water repellency (wettability) determination of ash samples collected following wildfires at four different Mediterranean conifer forest sites in eastern Spain were conducted to provide insights into variations in key chemical and physical characteristics of ash. TGA allowed the evaluation of organic matter (OM) and inorganic carbonate (IC) characteristics and their role in ash wettability. Thermogravimetric profiles were recorded for 40 ash samples (ten from each site). The persistence of water repellency of all ash samples was assessed by the Water Drop Penetration Time (WDPT) test. OM contents decreased, whilst OM stability indices and IC con…
Divergent reactivity of nucleophilic 1-bora-7a-azaindenide anions
2017
The reactions of 1-bora-7a-azaindenide anions, prepared in moderate to excellent yields by reduction of the appropriate 1-bora-7a-azaindenyl chlorides with KC8 in THF, with alkyl halides and carbon dioxide were studied. With alkyl halides (CH2Cl2, CH3I and BrCH(D)CH(D)tBu), the anions behave as boron anions, alkylating the boron centre via a classic SN2 mechanism. This was established with DFT methods and via experiments utilizing the neo-hexyl stereoprobe BrCH(D)CH(D)tBu. These reactions were in part driven by a re-aromatization of the six membered pyridyl ring upon formation of the product. Conversely, in the reaction of the 1-bora-7a-azaindenide anions with CO2, a novel carboxylation of …
Nitrate removal microbiology in woodchip bioreactors : a case-study with full-scale bioreactors treating aquaculture effluents
2020
Woodchip bioreactors are viable low-cost nitrate (NO3−) removal applications for treating agricultural and aquaculture discharges. The active microbial biofilms growing on woodchips are conducting nitrogen (N) removal, reducing NO3− while oxidizing the carbon (C) from woodchips. However, bioreactor age, and changes in the operating conditions or in the microbial community might affect the NO3− removal as well as potentially promote nitrous oxide (N2O) production through either incomplete denitrification or dissimilatory NO3− reduction to ammonium (DNRA). Here, we combined stable isotope approach, amplicon sequencing, and captured metagenomics for studying the potential NO3− removal rates, a…
Measurement of Atmospheric Neutrino Oscillations at 6–56 GeV with IceCube DeepCore
2018
We present a measurement of the atmospheric neutrino oscillation parameters using three years of data from the IceCube Neutrino Observatory. The DeepCore infill array in the center of IceCube enables the detection and reconstruction of neutrinos produced by the interaction of cosmic rays in Earth's atmosphere at energies as low as ∼5 GeV. That energy threshold permits measurements of muon neutrino disappearance, over a range of baselines up to the diameter of the Earth, probing the same range of L/Eν as long-baseline experiments but with substantially higher-energy neutrinos. This analysis uses neutrinos from the full sky with reconstructed energies from 5.6 to 56 GeV. We measure Δm322=2.31…
Indijas klimata migrācijas analīze. Feminisma perspektīva
2021
Klimata pārmaiņas turpinās atstāt postošas sekas ne tikai uz ekosistēmām, bet arī cilvēkiem visur pasaulē. Jau šobrīd to ietekmē marginalizētajām grupām globālajos Dienvidos nākas migrēt. Tomēr šo grupu sociālajām identitātēm mijiedarbojoties, veidojas unikālas pieredzes, kā rezultātā attiecības ar migrāciju nevar uzskatīt par viennozīmīgām. Feminisma perspektīva palīdz izprast to attiecības ar migrāciju, veidus, kādos konkrētas sabiedrības grupas piedzīvo klimata pārmaiņas. Intersekcionālais feminisms piedāvā sociālo nevienlīdzību mijiedarbību, varas attiecību analīzi un var palīdzēt turpmāk veidot imigrācijas politiku, kas iekļauj sociālo klimata pārmaiņu aspektu. Darbā veikta Indijas kli…
Review of immediate cardiac response in intertidal gastropods limpets at varying temperature, salinity and air exposure
2009
In 1990 Depledge and Andresen developed a #eld/laboratory, non-invasive technique to monitor the immediate response of cardiac activity in bivalves. Since then, several researchers have experienced and tested the variability of heart beat rate (HBR)and of associated metabolic rates under di$erent conditions in intertidal molluscs. Review of HBR immediate response in acute exposure and acclimation to changes of salinity, thermal stressors and air exposure were examined to test di$erent hypothesis. In intertidal Mediterranean and tropical limpets, the decrease in metabolic rate with a decrease in salinity was di$erent in animals experiencing di$erent degrees of salinity !uctuation in their re…
Heart beat rate: a physiological response to thermal stress in blue mussels species.
2009
Non-native species often have ecological impacts on invaded communities. The quanti#cation of features of invaders and recipient ecosystems facilitating and/or interfering with successful invasion remains a challenge because of several factors may in!uence the success of invasions. Among them, life history strategies (e.g., reproductive potential, body size), ability to avoid predators, disease resistance and physiological compensatory mechanisms to adapt to changing habitats are among the most important factors. The latter has been often invoked as the key to success for many intertidal invasive invertebrates and have been suggested as key indicators of invasibility rate and the ultimate d…
Identifying suitable proxies for climate change impacts in shallow Mediterranean habitats: sponge filtration not a ready-to-use tool yet
2009
The identi#cation of reliable proxies is crucial to undertake experimental manipulation and test hypotheses on climate change impacts. We evaluated the potential use of sponge #ltering activity as a proxy for the e$ect of temperature (T) increase in shallow marine habitats since: i) Porifera are ubiquitous, sessile and long-lived aquatic organisms; ii) Porifera are active #lter feeders and play a key-role in benthic-pelagic coupling; iii) #ltering activity already proved reliable to detect T e$ects on bivalves. The systematic screening of current literature to gather data and test the assumption “T increase -> increase in sponge #ltering activity” led to a #rst list of 840 sources (title re…
A Study of Osmosis Rate Through Several Proton Conducting Polymer Composite Membranes
2021
Carbon dioxide is typically considered to be a byproduct of various industrial processes that should not be released into the environment due to its nature as a harmful greenhouse gas. One of the more promising ways to dispose of it in an economical and environmentally friendly way is by using it as a raw material in electrochemical synthesis reactors. An important part of such reactors is an ion exchange membrane. In this study the influence of ZrO2 content in SPEEK – ZrO2 composite membranes on rate of osmosis trough them was investigated, with the goal of evaluating ZrO2 as an additive for making ion exchange membranes with fine-tuned osmotic permeability.