scholarly journals Influence of Different Thermal Aging Conditions on Soot Combustion with Catalyst by Thermogravimetric Analysis

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3647
Author(s):  
Yi Yang ◽  
Jia Fang ◽  
Junfeng Huang ◽  
Zihan Qin ◽  
Qian Zhang ◽  
...  
Keyword(s):  
Thermal Aging ◽  
Aging Process ◽  
Weight Ratio ◽  
Stability Index ◽  
Combustion Stability ◽  
Particulate Filter ◽  
Oxygen Absorption ◽  
Soot Combustion ◽  
Combustion Performance ◽  
Aging Conditions

Diesel particulates are deposited in the diesel particulate filter and removed by the regeneration process. The Printex-U (PU) particles are simulated as the diesel soot to investigate the influence of thermal aging conditions on soot combustion performance with the addition of catalysts. The comprehensive combustion index S, combustion stability index Rw and peak temperature Tp are obtained to evaluate the combustion performance. Compared with the PU/Pt mixtures of different Pt contents (2 g/ft3, 3.5 g/ft3, and 5 g/ft3), the 10 g/ft3 Pt contents improve soot combustion with the outstanding oxygen absorption ability. When the weight ratio of PU/Pt mixture is 1:1, the promoted effect achieves the maximum degree. The S and Rw increase to 8.90 × 10−8 %2min−2°C−3 and 39.11 × 105, respectively, compared with pure PU. After the thermal aging process, the PU/Pt mixture with a 350 °C aging temperature for 10 h promotes the soot combustion the best when compared to pure PU particles. It is not good as the PU/Pt mixture without aging, because the inner properties of soot and Pt/Al2O3 catalyst may have been changed. The S and Rw are 9.07 × 10−8 %2min−2°C−3 and 38.39 × 105, respectively, which are close to the no aging mixture. This work plays a crucial role in understanding the mechanism of the comprehensive effect of soot and catalyst on soot combustion after the thermal aging process.

A FORECAST OF PRODUCTIVE LONGEVITY OF HOLSTEIN COWS BY INDIRECT SIGNS

2020 ◽  
Author(s):  
З.С. САНОВА
Keyword(s):  
Correlation Coefficient ◽  
Aging Process ◽  
Direct Relationship ◽  
Stability Index ◽  
Age At First Calving ◽  
Group I ◽  
Predicted Values ◽  
The Stability ◽  
Relationship Of ◽  
The Relationship

В статье представлены материалы о взаимосвязи продолжительности продуктивного использования коров с характеристикой устойчивости к деградации, с возрастом отела и удоем. В исследованной, разнородной по происхождению, группе животных для прогноза продуктивного периода коров, обусловленного устойчивостью к деградации и возрастом первого отела, пригодно уравнение регрессии, аргументами в котором являются индекс устойчивости, возраст первого отела в первой и второй степенях. Коэффициент корреляции межу предсказанными значениями продуктивного периода и его фактическими величинами в I группе составляет 0,502, во II - 0,604. При этом крайние варианты прогнозируются со статистическими ошибками 5 мес при оценке индекса устойчивости по 2 лактациям и 4,1 мес по 3, а средние варианты, соответственно, 1,6 и 1,51 мес. Индекс устойчивости к процессу старения является важной характеристикой биологических особенностей коров, определяющий их продуктивное долголетие. Его оценка по первым 2 и 3 лактациям имеет прямолинейную связь с продуктивным периодом (r=0,4109 и r=0,5270), соответственно. Зависимость продуктивного периода от возраста первого отела криволинейная — с увеличением возраста первого отела сокращается срок продуктивного использования, при возрасте первого отела более 1400 дней срок продуктивного использования колеблется от 1,33 до 1,41 лактации. Коэффициент корреляции между этими характеристиками коров составляет - 0,2164 в I и - 0,2620 во II группах. The article presents materials about the relationship of the duration of productive use of cows with the characteristic of resistance to degradation, with the age of calving and milk yield. In the studied group of animals, which is heterogeneous in origin, the regression equation is suitable for predicting the productive period of cows due to resistance to degradation and the age of the first calving, the arguments of which are the stability index, the age of the first calving in the first and second degrees. The correlation coefficient between the predicted values of the productive period and its actual values in group I is 0.502, in group II - 0.604. At the same time, the extreme variants are predicted with statistical errors of 5 months when evaluating the stability index for 2 lactations and 4.1 months for 3, and the average variants, respectively, are 1.6 and 1.51 months. The index of resistance to the aging process is an important characteristic of the biological characteristics of cows, which determines their productive longevity. Its estimate for the first 2 and 3 lactations has a direct relationship with the productive period (r=0.4109 and r=0.5270), respectively. The dependence of the productive period age at first calving curvilinear with increasing age at first calving reduces the time to productive use, while age at first calving of more than 1400 days, the period of productive use ranges from 1.33 to 1.41 lactation. The correlation coefficient between these characteristics of cows is-0.2164 in I and-0.2620 in II groups.

scholarly journals Neural Model for the Prediction of Volume Losses in the Aging Process of Rums

2020 ◽  
Vol 29 (54) ◽  
pp. e10514
Author(s):  
Beatriz García-Castellanos ◽  
Osney Pérez-Ones ◽  
Lourdes Zumalacárregui-de-Cárdenas ◽  
Idania Blanco-Carvajal ◽  
Luis Eduardo López-de-la-Maza
Keyword(s):  
Aging Time ◽  
Aging Process ◽  
Neural Model ◽  
Correlation Factor ◽  
Coefficient Of Determination ◽  
Training Algorithms ◽  
The Neural Network ◽  
Aging Conditions ◽  
The Mean ◽  
Input Variables

The rum aging process shows volume losses, called wastage. The numerical operation variables: product, boardwalk, horizontal and vertical positions, date, volume, alcoholic degree, temperature, humidity and aging time, recorded in databases, contain valuable information to study the process. MATLAB 2017 software was used to estimate volume losses. In the modeling of the rum aging process, the multilayer perceptron neuronal network with one and two hidden layers was used, varying the number of neurons in these between 4 and 10. The Levenberg-Marquadt (LM) and Bayesian training algorithms were compared (Bay) The increase in 6 consecutive iterations of the validation error and 1,000 as the maximum number of training cycles were the criteria used to stop the training. The input variables to the network were: numerical month, volume, temperature, humidity, initial alcoholic degree and aging time, while the output variable was wastage. 546 pairs of input/output data were processed. The statistical Friedman and Wilcoxon tests were performed to select the best neural architecture according to the mean square error (MSE) criteria. The selected topology has a 6-4-4-1 structure, with an MSE of 2.1∙10-3 and a correlation factor (R) with experimental data of 0.9898. The neural network obtained was used to simulate thirteen initial aging conditions that were not used for training and validation, detecting a coefficient of determination (R2) of 0.9961.

Synergistic Interactions During Cocombustion of Lignite, Biomass, and Their Chars

2019 ◽  
Vol 141 (12) ◽  
Author(s):  
A. Caliskan Sarikaya ◽  
H. Haykiri Acma ◽  
S. Yaman
Keyword(s):  
Hybrid Poplar ◽  
Stability Index ◽  
Point Of View ◽  
Analysis Method ◽  
Ignition Point ◽  
Combustion Performance ◽  
Synergistic Interactions ◽  
Fuel Blends ◽  
Combustion Reactivity ◽  
Burning Stability

Woody biomasses such as ash tree (AT), hybrid poplar (HP), and rhododendron (RD) were subjected to torrefaction and carbonization at temperatures of 200 °C and 400 °C. Likewise, several lignite samples were carbonized at 750 °C. Various binary fuel blends such as raw lignite/raw biomass, raw lignite/biochar, lignitic char/raw biomass, and lignitic char/biochar were prepared where the fraction of biomass or biochar was 10 wt% in the blends. The cocombustion characteristics of these blends were investigated through a thermal analysis method from the synergetic point of view considering the fuel properties and the combustion performance. Some parameters relevant to the combustion reactivity such as ignition point, maximum rate, peak temperature, and burnout temperature were commented to figure out whether synergistic interaction or additive behavior governs the combustion characteristics of the blends. Also, the combustion performance indices such as ignition index (Ci), burnout index (Cb), comprehensive combustibility index (S), and the burning stability index (DW) were estimated. It was concluded that the combinations of the additive behavior and the synergistic interactions governs the cocombustion process, and the kind of the fuels and their thermal history determine the reactivity and the interactions during cocombustion.

scholarly journals Fatigue Cycles and Performance Evaluation of Accelerating Aging Heat Treated Aluminum Semi Solid Materials Designed for Automotive Dynamic Components

2020 ◽  
Vol 10 (9) ◽  
pp. 3008
Author(s):  
Mohamed Attia ◽  
Khaled Ahmed Ragab ◽  
Mohamed Bouazara ◽  
X.-Grant Chen
Keyword(s):  
Fatigue Life ◽  
Thermal Aging ◽  
Weight Ratio ◽  
Dynamic Component ◽  
Specific Strength ◽  
Suspension Control ◽  
Dynamic Components ◽  
Semi Solid ◽  
Automotive Suspension ◽  
Von Mises

The A357-type (Al-Si-Mg) aluminum semi solid casting materials are known for their excellent strength and good ductility, which make them materials of choice, preferable in the manufacturing of automotive dynamic mechanical components. Semi-solid casting is considered as an effective technique for the manufacturing of automotive mechanical dynamic components of superior quality performance and efficiency. The lower control arm in an automotive suspension system is the significant mechanical dynamic component responsible for linking the wheels of the vehicle to the chassis. A new trend is to manufacture this part from A357 aluminum alloy due to its lightweight, high specific strength, and better corrosion resistance than steel. This study proposes different designs of a suspension control arm developed, concerning its strength to weight ratio. Furthermore, this study aims to investigate the effect of accelerating thermal aging treatments on the fatigue life of bending fatigue specimens manufactured from alloy A357 using the Rheocasting semi-solid technology. The results revealed that the multiple aging cycles, of WC3, indicated superior fatigue life compared to standard thermal aging cycles. On the other hand, the proposed designs of automotive suspension control components showed higher strength-to-weight ratios, better stress distribution, and lower Von-Mises stresses compared to conventional designs.

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