A5055657419- Phytochemicals and Antioxidant Activities
- Lignin and Wood Chemistry
- Plant biochemistry and biosynthesis
- biodegradable polymer synthesis and properties
- Natural Fiber Reinforced Composites
- Smart Grid Energy Management
- Material Properties and Applications
- Mechanical Behavior of Composites
- Building Energy and Comfort Optimization
- Nanocomposite Films for Food Packaging
- Higher Education Learning Practices
- Nanoparticle-Based Drug Delivery
- Horticultural and Viticultural Research
- Induction Heating and Inverter Technology
- IoT-based Smart Home Systems
- Currency Recognition and Detection
- Antioxidant Activity and Oxidative Stress
- Concrete Corrosion and Durability
- Plant-Derived Bioactive Compounds
- Ginkgo biloba and Cashew Applications
- Adsorption, diffusion, and thermodynamic properties of materials
- Surfactants and Colloidal Systems
- Cultural Heritage Materials Analysis
- Polymer Science and Applications
- Additive Manufacturing and 3D Printing Technologies
Riga Technical University
2014-2018
Polymer Research Institute
1982
Abstract Oligomeric proanthocyanidins (OPC) rich extracts (OPCEs) were isolated by sequential extraction from the bark of deciduous trees grey alder ( Alnus incana ), black glutinosa ) and goat willow Salix caprea ). The yields OPCE all barks under study rather similar varied between 12.3% 15.4% based on oven dry (o.d.) bark. Content in OPCEs ranged 16.6% to 25% o.d. extract. characterised means antioxidant activity with ABTS˙ + DPPH˙ radical scavenging tests. All being introduced into...
The bark of deciduous trees grown in Latvia: grey alder, black ash tree and goat willow were sequentially extracted using solvents increasing polarity. data about total content both lipophilic hydrophilic compounds obtained extraction with hexane ethanol. highest yields extractives found for alder barks (25.7% 25.8%, respectively). Hydrophilic extract from the species contained high amount (up to 12% on dry mass) condensed tannins (CT) or oligomeric proanthocyanidins, whereas CT ach was...
IoT solutions enable to gather more detailed consumption and sensor data, paper deals with real measurements, where as a measurement object university faculty building is selected, that has Building Management system, lighting, HVAC systems, in it comparable also industrial building. For data analysis, parameters like electrical power consumption, room temperatures, humidity, CO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> levels,...
The barks of deciduous trees spread over a wide area Northern Europe, were sequentially extracted using solvents increasing polarity. highest yields hydrophilic extractives found for ash tree and goat willow (23.6% 23.8%, respectively). total contents polyphenols black alder bark (0.18 GAE·g-1 0.12 GAE·g-1, Hydrophilic extract from the both grey contained high amount (up to 7% on dry mass) condensed tannins (CT) or oligomeric proanthocyanidins (OPC). In tests with free radicals (ABTS•+,...
The aim of the research is to develop a new energy management model for building HVAC systems that would enable use sensors allow data aggregation and analysis.The developed based on five resistances, one capacitance (5R1C) consumption calculation described in ISO 13790:2008 standard used space heating residential nonresidential buildings.The 5R1C improved by taking into account additional parameters, like infiltration system heat capacity, which leads 8R2C order gain more accurate...
The main goal of the presented study is development two agrofibres – hemp/flax and hemp/hemp shive reinforced hybrid biocomposites based on waterborne polymer matrix system blends biodegradable polyhydroxybutyrate (PHB) poly(vinyl alcohol) (PVA). correlation between agrofibre ratio mechanical characteristics has been established. positive effect optimal results in terms strength have found 4:1 ratio. elaborated are considered soil, their mass loss to be ≥ 52 % … 54 from initial during 5 months.
Formation process of flax fiber reinforced biocomposites based on waterborne matrix systems from modified polymers - polyhydroxybutyrate, poly (vinyl alcohol) was developed by suspension casting technique. Two kind as reinforcement employed Latvian variety Vega-2 and combing. The correlation between composition, origin, content mechanical characteristics, water vapour absorption biodegradability established. Optimal characteristics elaborated eco-composites were obtained use combing with ~ 30 wt. %.