scholarly journals Water splitting into hydrogen and oxygen by non-traditional redox inactive zinc selenolate electrocatalyst

2020 ◽  
Author(s):  
Aditya Upadhyay ◽  
Saurav KV ◽  
Manish Kumar ◽  
Evelin Varghese ◽  
Ananda Hodage ◽  
...  
Keyword(s):  
Rate Constant ◽  
Metal Ion ◽  
Alternative Energy ◽  
Lewis Acidity ◽  
Onset Potential ◽  
Alternative Energy Sources ◽  
Cooperativity Effect ◽  
Electrochemically Active ◽  
And Control ◽  
Electrochemical Oxygen

Abstract The development of alternative energy sources is the utmost priority of the developing society. Unlike many prior homogenous electrocatalysts that rely on the change in an oxidation state of metal center and or electrochemically active ligand, the synthesized novel bimetallic zinc selenolate complex consisting of redox inactive zinc metal ion and catalytically inactive ligand catalyzes the electrochemical oxygen evolution from the water with rate constant 7.28 s-1 at onset potential 1.028 V vs. NHE. On the other hand, the hydrogen evolution reaction proceeds with 47.32 s-1 observed rate constant and -0.256 V onset potential vs. NHE. DFT computations and control experiments suggest that the redox chemistry at selenium center, Lewis acidity, and cooperativity effect of two zinc atoms facilitate the electrochemical oxidation and reduction of water into oxygen and hydrogen, respectively.

scholarly journals GUIDED INQUIRY AND GUIDED DISCOVERY MODEL IN SCIENCE LEARNING TO ‎IMPROVE COGNITIVE ABILITY OF JUNIOR HIGH SCHOOL STUDENTS

EDUSAINS ◽  
2017 ◽  
Vol 9 (2) ◽  
Author(s):  
Syafrilianto Syafrilianto Syafrilianto ◽  
Taufik Rahman
Keyword(s):  
High School ◽  
Cognitive Ability ◽  
Junior High School ◽  
Alternative Energy ◽  
Science Learning ◽  
Energy Sources ◽  
Guided Inquiry ◽  
Guided Discovery ◽  
Alternative Energy Sources ◽  
And Control

This study aims to find out the improvement of cognitive ability through the implementation of guided inquiry and guided discovery model in integrated natural science learning. Alternative energy sources was chosen as the learning theme which contain Biology, Physic, Chemistry concepts, which consist of briquettes as the heat source, and battery as the power source. This study used quasi experiment method with matching only pretest posttest control group design. The subject of this study were 42 students of VII grade of Junior High School in Kampar District which consist of experiment and control class with 21 students in each class. Student cognitive learning outcomes was measured by multiple choice test instrument, which contain of 21 items which was done twice (pretest and posttest). The technic of data analysis was normality test and hypothesis test (U test). Data were analyzed by IBM SPSS 22 statistics and Microsoft Excel 2010 program. The N-Gain average of cognitive ability shows that there is an improvement of student cognitive ability in experiment class as 0,44 with intermediate category, and in control class as 0,21 with low category. While, the result of U test toward N-Gain value shows that there is a significant difference on student cognitive ability between students in experiment and control class. Thus, it can be concluded that guided inquiry model can improve student cognitive ability more than guided discovery model. Keywords: guided inquiry model, discovery guided model, cognitive ability, alternative energy sources

Recent Progress in Quasi-Solid and Solid Polymer Electrolytes for Multivalent Metal Ion Batteries

2021 ◽  
Author(s):  
Jiahui Lu ◽  
Pauline Jaumaux ◽  
Tianyi Wang ◽  
Chengyin Wang ◽  
Guoxiu Wang
Keyword(s):  
Metal Ion ◽  
Alternative Energy ◽  
Rapid Development ◽  
Solid Polymer Electrolytes ◽  
Solid Polymer ◽  
Alternative Energy Sources ◽  
New Energy ◽  
Increasing Demand ◽  
Storage Technologies ◽  
Multivalent Metal

The increasing demand for alternative energy sources promotes the rapid development of new energy storage technologies. Multivalent ion batteries (MIBs) such as zinc (Zn), calcium (Ca), aluminum (Al), and magnesium...

Development of the algorithm for the selection of a wind generator-based autonomous power supply system

2019 ◽  
Vol 2 (1) ◽  
pp. 8-16 ◽  
Author(s):  
P. A. Khlyupin ◽  
G. N. Ispulaeva
Keyword(s):  
Wind Turbines ◽  
Power Supply ◽  
Alternative Energy ◽  
Power Supply System ◽  
Supply System ◽  
Power Generators ◽  
Energy Devices ◽  
Wind Generator ◽  
Alternative Energy Sources ◽  
Selection Of

Introduction: The co-authors provide an overview of the main types of wind turbines and power generators installed into wind energy devices, as well as advanced technological solutions. The co-authors have identified the principal strengths and weaknesses of existing wind power generators, if applied as alternative energy sources. The co-authors have proven the need to develop an algorithm for the selection of a wind generator-based autonomous power supply system in the course of designing windmill farms in Russia. Methods: The co-authors have analyzed several types of wind turbines and power generators. Results and discussions: The algorithm for the selection of a wind generator-based autonomous power supply system is presented as a first approximation. Conclusion: The emerging algorithm enables designers to develop an effective wind generator-based autonomous power supply system.

Energetic comparison of some stump-removing methods

2014 ◽  
Vol 10 (1) ◽  
pp. 35-51
Author(s):  
I. Czupy
Keyword(s):  
Alternative Energy ◽  
Fossil Fuel ◽  
Alternating Current ◽  
Above Ground Biomass ◽  
Alternative Energy Sources ◽  
Wide Domain ◽  
Fuel Substitution ◽  
Unused Resource ◽  
Root Connection ◽  
Different Soils

Concerns about climate change and fossil fuel shortages are encouraging interest in stumps, as alternative energy sources. Stumps are an almost unused resource in the context of bio fuels. Stump harvesting signifies an intensification of forest management compared with conventional stem-only or above-ground biomass-only harvesting. There are many benefits of stump harvesting. These include: the production of wood fuel, fossil fuel substitution, and improved soil preparation.Removing tree trunks in Hungary has been going on according to the principle of stump extraction, which means stumps are removed by grabbing technology. Experiments have been carried out to reduce the extraction force. In the Great Hungarian Lowland, where large areas require the operation implementation, stump extraction is done by special, hydraulic driven baggers equipped with a special bucket. During operation of the equipment, we carried out measurements of the extraction force and the time requirement. The experiments are designed to carry out the measurements with different soils and different tree species. According to our proposal the suitable force and torque required to remove stumps can be significantly reduced if before the lifting the soil — root connection is loosened. One of the possible ways to implement this task is the use of vibration. Since relatively great vibration power and wide domain of frequency are necessary, therefore we prepared the loosening machinery elements of alternating-current hydraulics system. Based on constructions variants we created a tractor-mounted experimental alternating-current hydraulic stump-loosening machine. It was designed with the ability to produce horizontal vibration in order to loosen stumps.

The development of alternative energy sources: Prospects in Russia and the world

2020 ◽  
Vol 16 (5) ◽  
pp. 885-904
Author(s):  
M.E. Frai
Keyword(s):  
Alternative Energy ◽  
Systems Approach ◽  
Energy Resource ◽  
Current Situation ◽  
Energy Sources ◽  
The Sustainable Development ◽  
Energy Complex ◽  
Alternative Energy Sources ◽  
Governmental Institutions ◽  
Key Steps

Subject. The article discusses limited sources of energy nowadays and an ongoing survey of new ones. I focus on fuel and energy complexes worldwide and in Russia. Objectives. The study is to analyze the future use of alternative energy sources in the fuel and energy complex nationwide and worldwide. I review the existing energy sources of the fuel and energy complex in the global and regional markets, specifically the alternative ones. Methods. The study relies upon methods of statistics, analysis and systems approach. Results. The article demonstrates that the fuel and energy complex strongly depends on the current situation in the energy resource market, which is difficult to forecast. If we continue relying on traditional energy resources, we get exposed to some risks affecting the sustainable development of the economy. Russia should diversify the power engineering sector by developing alternative energy sources. The article sets forth the economic rationale for alternative sources and key steps Russia shall make. Conclusions and Relevance. Considering the current situation in the energy balance, alternative energy is what any advanced society seeks for, being supported by manufacturers, governmental institutions, and researchers, though low profitability and high infrastructure costs impede its development. In Russia, these challenges are even more palpable. However, even now Russia is able to find alternative energy solutions. In addition to advantages of alternative energy, which is globally proclaimed, they will also help Russia diversify and update the economic system.

ALTERNATIVE ENERGY SOURCES IN TRANSITION COUNTRIES. THE CASE OF BIO-ENERGY IN THE UKRAINE

2006 ◽  
Vol 5 (3) ◽  
pp. 471-486
Author(s):  
Andrius Plepys ◽  
Jean-Philippe Boutin ◽  
Giulia Gervasoni ◽  
Robert Hlep ◽  
Kristin Seyboth ◽  
...  
Keyword(s):  
Alternative Energy ◽  
Transition Countries ◽  
Energy Sources ◽  
Alternative Energy Sources
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