Estimation of Explosive Energy Output by EXPLO5 Thermochemical Code

Timber has the lowest embodied energy of any of the construction materials. Paper production from trees requires much more energy. There is some energy saving in recycling, as recycled paper substitutes for pulp derived from wood chips. Growing crops for food also requires energy. The energy required for plants to grow comes from the sun, but there are additional energy inputs from fertiliser and farm machinery to speed up the growth process and vastly improve crop yields. If grains are used as animal feed, then the energy inputs are much larger than the dietary energy output—the larger the animal and the longer it is fattened up before slaughter, the more inefficient the process. The use of crops to make fuel for electrical power generation or for processing into liquid fuels is horribly inefficient. The problem is simple—the plants do not grow fast enough!

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Mechanochemical synthesis of poly(trimethylene carbonate)s: an example of rate acceleration

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.15.93 ◽

2019 ◽

Vol 15 ◽

pp. 963-970 ◽

Cited By ~ 10

Author(s):

Sora Park ◽

Jeung Gon Kim

Keyword(s):

Ball Milling ◽

Mechanochemical Synthesis ◽

Polymeric Materials ◽

Solvent Free ◽

Energy Output ◽

Polymerization Temperature ◽

Mechanical Degradation ◽

Trimethylene Carbonate ◽

Rate Acceleration ◽

Conventional Solution

Mechanochemical polymerization is a rapidly growing area and a number of polymeric materials can now be obtained through green mechanochemical synthesis. In addition to the general merits of mechanochemistry, such as being solvent-free and resulting in high conversions, we herein explore rate acceleration under ball-milling conditions while the conventional solution-state synthesis suffer from low reactivity. The solvent-free mechanochemical polymerization of trimethylene carbonate using the organocatalysts 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) and 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) are examined herein. The polymerizations under ball-milling conditions exhibited significant rate enhancements compared to polymerizations in solution. A number of milling parameters were evaluated for the ball-milling polymerization. Temperature increases due to ball collisions and exothermic energy output did not affect the polymerization rate significantly and the initial mixing speed was important for chain-length control. Liquid-assisted grinding was applied for the synthesis of high molecular weight polymers, but it failed to protect the polymer chain from mechanical degradation.

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Research on the methods and means of action strength training in aerobics training

International Journal of Electrical Engineering Education ◽

10.1177/00207209211004225 ◽

2021 ◽

pp. 002072092110042

Author(s):

Xiaona Yang ◽

Yang Ji ◽

Da Ke ◽

Fang Li

Keyword(s):

Strength Training ◽

Team Member ◽

High Efficiency ◽

Colleges And Universities ◽

The Body ◽

Energy Output ◽

Control Group ◽

Experimental Sample ◽

Training Method ◽

Core Strength

Aerobics is a beautiful and rhythmic sport. In recent years, aerobics has developed rapidly, and has become one of the essential courses of physical education in Colleges and universities. But the existing aerobics courses in Colleges and universities are less involved in the training process of action strength. Lack of strength quality is a common shortcoming of Aerobics Athletes in Colleges and universities. Therefore, this paper puts forward the methods and means of action strength training in aerobics training. According to the characteristics of competitive aerobics, combined with the traditional training strategy of action strength, this paper formulates the method of action strength training suitable for College Aerobics athletes. In order to further verify the effectiveness of this method, this paper takes a university aerobics team as an experimental sample to carry out a comparative analysis of the effect of action strength training. Relevant studies have proved that core strength training has the following effects on aerobics players: 1. Helps the calisthenics team member stabilize the trunk, improve the body's control ability and balance ability. 2. It is conducive to completing difficult movements of calisthenics with high efficiency and low energy consumption. 3. Helps the aerobics team member to enhance the special strength. 4. It can effectively prevent sports injuries. 5. It can improve the direction change and displacement speed of the body. 6. It can improve the energy output of the core strength to the limbs and other muscle groups during movement, so that the movement can be completed more perfectly.According to the results of the experiment, the explosive force and endurance of the experimental group after 8 weeks of training have been significantly improved, and formed a more obvious difference with the control group. The aerobics training method developed in this paper can be divided into two stages: the initial stage and the middle stage, which can better meet the students with different physical qualities. At the end of this paper, a fast strength training method is introduced, and the characteristics of different training methods are analyzed.

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New Deterministic Mathematical Model for Estimating the Useful Energy Output of a Medium-Sized Solar Domestic Hot Water System

Energies ◽

10.3390/en14102753 ◽

2021 ◽

Vol 14 (10) ◽

pp. 2753

Author(s):

Miroslaw Zukowski ◽

Walery Jezierski

Keyword(s):

Thermal Power ◽

Optimization Procedure ◽

Climatic Conditions ◽

Point Of View ◽

Hot Water ◽

Energy Output ◽

Daily Consumption ◽

Software Environment ◽

Optical Efficiency ◽

Domestic Hot Water

According to the authors of this paper, the mathematical point of view allows us to see what sometimes cannot be seen from the designer’s point of view. The aim of this study was to estimate the influence of the most important parameters (volume of heat storage tanks, daily consumption of domestic hot water, optical efficiency, heat loss coefficient, and total area of a solar collector) on the thermal power output of solar domestic hot water (SDHW) system in European climatic conditions. Three deterministic mathematical models of these relationships for Madrid, Budapest, and Helsinki were created. The database for the development of these models was carried out using computer simulations made in the TRNSYS software environment. The SDHW system located at the Bialystok University of Technology (Poland) was the source of the measurement results used to validate the simulation model. The mathematical optimization procedure showed that the maximum annual useful energy output that can be obtained from 1 m2 of gross collector area is 1303 kWh in the case of Madrid, 918.5 kWh for Budapest, and 768 kWh for Helsinki weather conditions.

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A Study of Developing a Prediction Equation of Electricity Energy Output via Photovoltaic Modules

Energies ◽

10.3390/en14051503 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1503

Author(s):

Minsu Kim ◽

Hongmyeong Kim ◽

Jae Hak Jung

Keyword(s):

Experimental Data ◽

Real Time ◽

Air Temperature ◽

Temperature Difference ◽

Prediction Accuracy ◽

Prediction Equation ◽

Energy Output ◽

Photovoltaic Modules ◽

Mean Error ◽

Pv Module

Various equations are being developed and applied to predict photovoltaic (PV) module generation. Currently, quite diverse methods for predicting module generation are available, with most equations showing accuracy with ≤5% error. However, the accuracy can be determined only when the module temperature and the value of irradiation that reaches the module surface are precisely known. The prediction accuracy of outdoor generation is actually extremely low, as the method for predicting outdoor module temperature has extremely low accuracy. The change in module temperature cannot be predicted accurately because of the real-time change of irradiation and air temperature outdoors. Calculations using conventional equations from other studies show a mean error of temperature difference of 4.23 °C. In this study, an equation was developed and verified that can predict the precise module temperature up to 1.64 °C, based on the experimental data obtained after installing an actual outdoor module.

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