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Tytuł:
Research on speed control of high-speed train based on multi-point model
Autorzy:
Hou, Tao
Guo, Yang-yang
Niu, Hong-xia
Powiązania:
https://bibliotekanauki.pl/articles/224081.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
high-speed train
multi-point model
predictive control
fuzzy control
PID control
speed control
pociąg ekspresowy
model wielopunktowy
sterowanie predykcyjne
sterowanie rozmyte
sterowanie PID
prędkość
Opis:
The traditional train speed control research regards the train as a particle, ignoring the length of the train and the interaction force between carriages. Although this method is simple, the control error is large for high-speed trains with the characteristics of power dispersion. Moreover, in the control process, if the length of the train is not considered, when the train passes the slope point or the curvature point, the speed will jump due to the change of the line, causing a large control error and reducing comfort. In order to improve the accuracy of high-speed train speed control and solve the problem of speed jump when the train runs through variable slope and curvature, the paper takes CRH3 EMU data as an example to establish the corresponding multi-point train dynamics model. In the control method, the speed control of high-speed train needs to meet the fast requirement. Comparing the merits and demerits of classical PID control, fuzzy control and fuzzy adaptive PID control in tracking the ideal running curve of high-speed train, this paper chooses the fuzzy adaptive PID control with fast response. Considering that predictive control can predict future output, a predictive fuzzy adaptive PID controller is designed, which is suitable for high-speed train model based on multi-point. The simulation results show that the multi-point model of the high-speed train can solve the speed jump problem of the train when passing through the special lines, and the predictive fuzzy adaptive PID controller can control the speed of the train with multi-point model, so that the train can run at the desired speed, meeting the requirements of fast response and high control accuracy.
Źródło:
Archives of Transport; 2019, 50, 2; 35-46
0866-9546
2300-8830
Pojawia się w:
Archives of Transport
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Vehicle detection in surveillance videos based on YOLOv5 lightweight network
Autorzy:
Wang, Yurui
Yang, Guoping
Guo, Jingbo
Powiązania:
https://bibliotekanauki.pl/articles/2173728.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
YOLOv5
MobileNetV2
lightweight network
vehicle detection
lekka sieć
detekcja pojazdu
Opis:
The development of surveillance video vehicle detection technology in modern intelligent transportation systems is closely related to the operation and safety of highways and urban road systems. Yet, the current object detection network structure is complex, requiring a large number of parameters and calculations, so this paper proposes a lightweight network based on YOLOv5. It can be easily deployed on video surveillance equipment even with limited performance, while ensuring real-time and accurate vehicle detection. Modified MobileNetV2 is used as the backbone feature extraction network of YOLOv5, and DSC “depthwise separable convolution” is used to replace the standard convolution in the bottleneck layer structure. The lightweight YOLOv5 is evaluated in the UA-DETRAC and BDD100k datasets. Experimental results show that this method reduces the number of parameters by 95% as compared with the original YOLOv5s and achieves a good tradeoff between precision and speed.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2022, 70, 6; art. no. e143644
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On existence of shape optimization for a p-Laplacian equation over a class of open domains
Autorzy:
Guo, Bao-Zhu.
Yang, D. H.
Powiązania:
https://bibliotekanauki.pl/articles/206462.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
Laplacian
shape optimization
existence
Opis:
In this paper, we introduce four new classes of open sets in general Euclidean space RN. It is shown that every such class of open sets is compact under the Hausdorff distance. The result is applied to a shape optimization problem of p-Laplacian equation. The existence of the optimal solution is presented.
Źródło:
Control and Cybernetics; 2014, 43, 1; 15-31
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Conceptual Design and Performance Analysis of an Exhaust Gas Waste Heat Recovery System for a 10000TEU Container Ship
Autorzy:
Ma, Zheshu
Yang, Dong
Guo, Qiang
Powiązania:
https://bibliotekanauki.pl/articles/259008.pdf
Data publikacji:
2012
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
exergy efficiency
marine diesel engine
thermal efficiency
waste heat recovery system
Opis:
According to operation characteristics of the main engine 9K98ME-C7, a combined turbines-exhaust gas waste heat recovery system is proposed to recover waste heat and increase system energy efficiency. Thermodynamic models based on the first thermodynamic law and the second thermodynamic law are formulated. The superheated steam yield, the total electric power yield, the first thermodynamic law efficiency, the exergy efficiency at different exhaust gas boiler working pressure, and the variation of the exergy efficiency under different feed water temperature and different steam turbine back pressure are analyzed. Thermodynamic results indicate that the most appropriate exhaust gas boiler pressure is 0.8MPa for studied main engine and the total thermal efficiency with combined turbines arrangement has climbed up to 53.8% from 48.5%.
Źródło:
Polish Maritime Research; 2012, 2; 31-38
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An investigation of continuous interaction process between air bubble and various roughness coal surfaces using microbalance
Autorzy:
Guo, Zhimin
Yang, Jianguo
Wang, Yuling
Powiązania:
https://bibliotekanauki.pl/articles/1450050.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
surface roughness
air bubble
contact angle
continuous interaction
Opis:
Surface roughness of particles plays an important role in bubble-particle interaction process. However, the continuous attachment and detachment process have rarely been characterized between the surface of different roughness and air bubble. In this study, the continuous attachment and detachment processes between the surface of different roughness and air bubble were investigated by a highly sensitive microbalance. The bubble–surface interaction process was monitored by a high-speed camera to analyze the geometry parameters, including distance, adhesion diameter, and contact angle. It was found that the bubble-particle attachment time increased with the increase of surface roughness. The magnitude of the repulsive force in the bubble-surface approaching process increased with the increase of surface roughness, while the attractive force in the bubble-particle retracting process decreased monotonically with the surface roughness. The force measured by microbalance was finally compared with the calculated one. The calculated force at the biggest force point also increased with the decrease of surface roughness. These results indicate that coal particles with lower surface roughness, which have less water-filled pores and pillars, is more conducive to flotation due to the lower repulsive force in the bubble-particle attachment process and higher adhesive force in the bubble-particle detachment process, and vice versa.
Źródło:
Physicochemical Problems of Mineral Processing; 2020, 56, 1; 11-23
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spin-Spin and Spin-Other-Orbit Interactions of Spin-Hamiltonian Parameters for $3d^{2(8)}$ Ions in $Al_2O_3$ Crystals
Autorzy:
Wei, Q.
Guo, L.
Yang, Z.
Wei, B.
Powiązania:
https://bibliotekanauki.pl/articles/1505102.pdf
Data publikacji:
2011-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
76.30.Fc
71.70.Ch
75.10.Dg
71.55.Ht
Opis:
By considering weaker magnetic interactions (including spin-spin and spin-other-orbit interactions) in Hamiltonian, the spin-Hamiltonian parameters, including the zero-field splitting parameter D and g factors $(g_∥, g_⊥)$ for $3d^{2(8)}$ ions in $Al_2O_3$ crystals have been investigated. The results show that the contributions to D, $g_∥$ and $g_⊥$ from the spin-orbit interaction are dominant. The contributions from weaker magnetic interactions to D decrease (increase) with increasing charge of impurity ions for $3d^2 (3d^8)$ ions.
Źródło:
Acta Physica Polonica A; 2011, 119, 6; 857-859
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Train based on virtual synchronous generator technology uninterrupted phase-separation passing study
Autorzy:
Wang, Ying
Yang, Huan
Chen, Xiaoqiang
Guo, Ya
Powiązania:
https://bibliotekanauki.pl/articles/27309940.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
energy storage railway power conditioner
single-phase inverter
uninterrupted
phase-separation passing
virtual synchronous generator
Opis:
The problem of large speed loss exists in the traditional passing through the electric phase-separation method of trains, which is more prominent when trains pass through an electric phase-separation zone in the uphill section of long ramps and may lead to the trains not passing through the phase-separation zone safely. In order to solve this problem, based on the energy storage type railroad power conditioner, a train uninterrupted phase-separation passing system based on the energy storage type railroad power conditioner is proposed. The energy storage railroad power conditioner can realize the recovery and utilization of regenerative braking energy of the electrified railroad. In the structure of the energy storage railroad power conditioner, the single-phase inverter is led from the middle DC side of the energy storage railroad power conditioner and connected to the neutral line through the LCL filter and the step-up transformer, which constitutes an uninterrupted phase separation passing system. The single-phase inverter is controlled using virtual synchronous generator technology, which allows the single-phase inverter to have external characteristics similar to those of a synchronous generator, providing support for the voltage and frequency in the neutral zone. The power required by the train to pass the electric phase-separation is provided by the power supply arm or the energy storage system, which not only improves the utilization rate of regenerative braking energy but also realizes the uninterrupted phase separation passing of the train through the control of the voltage in the neutral region.
Źródło:
Archives of Electrical Engineering; 2023, 72, 3; 755--768
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Availability analysis for a multi-component system with different k-out-of-n:G warm standby subsystems subject to suspended animation
Analiza gotowości systemu wieloelementowego składającego się z różnych wygaszalnych podsystemów typu k-z-n:G stanowiących rezerwę ciepłą
Autorzy:
Wang, Yu
Guo, Linhan
Wen, Meilin
Yang, Yi
Powiązania:
https://bibliotekanauki.pl/articles/1365298.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
availability
multi-component series system
k-out-of-n:G warm standby subsystem
suspended animation
Markov process
gotowość
wieloelementowy system szeregowy
podsystem k-z-n:G
rezerwa ciepła
wygaszanie
proces Markowa
Opis:
Industrial equipment or systems are usually constructed as a multi-component series system with k-out-of-n:G subsystems to fulfill a specified function. As a common type of standby, warm standby is considered in the multi-component series system with k-outofn:G standby subsystems. When a subsystem fails, the non-failed subsystems are shut off and cannot fail, which is defined as suspended animation (SA). If the SA is ignored the non-failed subsystems are assumed to keep working in the SA time, which will cause inaccuracy in the availability analysis for the system. In this paper, we focus on the SA to construct an availability model for a multi-component series system with k-out-of-n:G warm standby subsystems. Multiple continuous time Markov chains are constructed to model the system availability. A Monte Carlo simulation has been carried out to verify our method. Several interesting findings are obtained. 1) The failure rates of subsystems with SA and their limits are derived. 2) The closed-form expressions for the stationary availability of the system and subsystems, mean time to failure, mean time to repair and stationary failure frequency are obtained considering SA. 3) The system stationary availability is a monotone function for its parameters. 4) The SA effect on the stationary availability should be emphasized in two cases, one is both the value of n/k and the failure rate of active components in a k-out-of-n subsystem are relatively large or small, the other is both the value of n/k and the repair rate are relatively small.
Aby urządzenia i systemy przemysłowe mogły pełnić swoje określone funkcje, zwykle buduje się je w postaci wieloelementowych systemów szeregowych składających się z podsystemów typu k-z-n: G. W pracy rozważano zagadnienie rezerwy ciepłej w wieloelementowym systemie szeregowym składającym się z podsystemów rezerwowych typu k-z-n: G. W przypadku awarii jednego z takich podsystemów, pozostałe, działające podsystemy wyłącza się, dzięki czemu nie mogą one ulec uszkodzeniu. Procedurę taką określa się, przez analogię z organizmami żywymi mianem anabiozy (suspended animation) lub wygaszania. Pominięcie zjawiska wygaszania, prowadzi do założenia, że podsystemy, które nie uległy uszkodzeniu pracują w czasie wygaszenia, co skutkuje nieprawidłowościami w analizie gotowości systemu. W artykule koncepcję wygaszania podsystemów wykorzystano do budowy modelu gotowości wieloelementowego systemu szeregowego składającego się z podsystemów typu k-z-n: G stanowiących rezerwę ciepłą. W celu zamodelowania gotowości systemu, skonstruowano łańcuchy Markowa z czasem ciągłym. Przedstawioną metodę zweryfikowano za pomocą symulacji Monte Carlo. Uzyskano szereg interesujących wyników. 1) Obliczono intensywność uszkodzeń podsystemów wygaszonych i ich wartości graniczne. 2) Wyprowadzono, z uwzględnieniem procedury wygaszania, wyrażenia w postaci zamkniętej dla stacjonarnej gotowości rozważanego systemu i podsystemów oraz określono średni czas do uszkodzenia, średni czas do naprawy oraz stacjonarną częstotliwość uszkodzeń. 3) Gotowość stacjonarna systemu jest funkcją monotoniczną dla parametrów wejściowych systemu. 4) Należy podkreślić wpływ wygaszania na stacjonarną gotowość systemu w dwóch przypadkach: gdy stosunek n/k i intensywność uszkodzeń aktywnych elementów k-tego spośród n podsystemów są względnie niskie lub względnie wysokie, oraz gdy stosunek n/k i intensywność napraw są względnie niskie.
Źródło:
Eksploatacja i Niezawodność; 2019, 21, 2; 289-300
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental study of fuel combustion and emission characteristics of marine diesel engines using advanced fuels
Autorzy:
Changxiong, Li
Hu, Yihuai
Yang, Zy
Guo, Hao
Powiązania:
https://bibliotekanauki.pl/articles/34615637.pdf
Data publikacji:
2023
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
marine diesel engine
PODE
combustion characteristics
emission performance
Opis:
In order to explore the potential application of oxygenated fuels, polyoxymethylene dimethyl ethers (PODE), as an alternative fuel for marine diesel engines, the fuel combustion performance and gas emission characteristics of pure diesel oil, diesel-blended PODE, and pure PODE were tested on a marine diesel engine under different running conditions. The experimental results indicate that oxygen consumption can be reduced by diesel-blended PODE and pure PODE. The in-cylinder pressure and exothermic curve were consistent with the trend of diesel oil. Also, the ignition delay of diesel-blended PODE and pure PODE decreased, and the diffusion rate was accelerated, which helped to improve the combustion performance of diesel engines. Diesel blended PODE and pure PODE reduced the particulate matter (PM) emissions by up to 56.9% and 86.8%, respectively, and CO emissions by up to 51.1% and 56.3%, respectively. NOx emissions were gradually decreased with engine load. CO2 emissions were slightly increased, and the effective fuel consumption was increased up to 48% and 132%, respectively. It was shown that PODE could provide comparable power in a marine diesel engine and improve the fuel combustion and gas emission of the engine as a clean alternative fuel for marine diesel engines.
Źródło:
Polish Maritime Research; 2023, 3; 48-58
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Maintenance policy of degradation components based on the two-phase Wiener process
Autorzy:
Song, Minqiao
Zhang, Yingzhi
Yang, Fang
Wang, Xiaofeng
Guo, Guiming
Powiązania:
https://bibliotekanauki.pl/articles/28328273.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
condition-based maintenance
two-phase inspection
two-phase Wiener process
Particle Swarm Optimization
sensitivity analysis
Opis:
This paper proposes a condition-based maintenance policy for the two-phase Wiener degradation process components. The main contribution of this article is to provide the time distribution of degradation failures for the two-phase Wiener process degradationcomponent, as well as the modeling and solving methods for two-phase maintenance. The two-phase maintenance policy includes two-phase inspection and preventive replacement maintenance operations. The established optimization maintenance policy model aims to minimize long-term operation costs. The specific cost calculation equation and the solution method of the maintenance model are given. The feasibility of the maintenance policy model is verified using the two-phase degradation data of the Liquid Coupling Devices. The Particle swarm optimization algorithm can stably solve the described problem, and the results show that the two-phase maintenance policy can be more economical and improve components availability. After that, we also analyzed the impact of the cost parameters on the maintenance policy through sensitivity analysis.
Źródło:
Eksploatacja i Niezawodność; 2023, 25, 4; art. no. 172537
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Thermodynamics and Kinetics Analysis on Carbothermic Reduction of Calcined Magnesite in Vacuum
Autorzy:
Tang, Qifeng
Ao, Jinqing
Peng, Biyou
Guo, Biao
Yang, Tao
Powiązania:
https://bibliotekanauki.pl/articles/2125546.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
calcined magnesite
carbothermic reduction
vacuum
thermodynamics
kinetics
Opis:
The carbothermic reduction of calcined magnesite in vacuum was studied. By thermodynamic analysis, the starting temperature of reduction reaction dropped from 2173K to 1523K when system pressure dropped from 1 atmosphere to 100 Pa. The experiments were carried out at different conditions under 10~100 Pa and the experimental results shown that the reduction extent of MgO improved by increasing the reaction temperature and time, the pellet forming pressure as well as adding fluoride as catalyst. The rate-determining step of carbothermic reduction process was gas diffusion with the apparent activation energy of 241.19~278.56 kJ/mol.
Źródło:
Archives of Metallurgy and Materials; 2022, 67, 3; 1021--1026
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A machine learning method for soil conditioning automated decision-making of EPBM : hybrid GBDT and Random Forest Algorithm
Autorzy:
Lin, Lin
Guo, Hao
Lv, Yancheng
Liu, Jie
Tong, Changsheng
Yang, Shuqin
Powiązania:
https://bibliotekanauki.pl/articles/2087007.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
soil conditioning
automated decision-making
hybrid algorithm
geological parameters
drive parameters
feature selection
Opis:
There lacks an automated decision-making method for soil conditioning of EPBM with high accuracy and efficiency that is applicable to changeable geological conditions and takes drive parameters into consideration. A hybrid method of Gradient Boosting Decision Tree (GBDT) and random forest algorithm to make decisions on soil conditioning using foam is proposed in this paper to realize automated decision-making. Relevant parameters include decision parameters (geological parameters and drive parameters) and target parameters (dosage of foam). GBDT, an efficient algorithm based on decision tree, is used to determine the weights of geological parameters, forming 3 parameters sets. Then 3 decision-making models are established using random forest, an algorithm with high accuracy based on decision tree. The optimal model is obtained by Bayesian optimization. It proves that the model has obvious advantages in accuracy compared with other methods. The model can realize real-time decision-making with high accuracy under changeable geological conditions and reduce the experiment cost.
Źródło:
Eksploatacja i Niezawodność; 2022, 24, 2; 237--247
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
GP5 protein - based ELISA for the detection of PRRSV antibodies
Autorzy:
Wang, Y.
Guo, J.
Qiuao, S.
Li, Q.
Yang, J.
Jin, Q.
Zhang, G.
Powiązania:
https://bibliotekanauki.pl/articles/30629.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Opis:
Porcine reproductive and respiratory syndrome virus (PRRSV) is an important swine pathogen, causing huge economic losses each year worldwide. Immunization with vaccines containing the glycoprotein 5 (GP5) of PRRSV is the main measure to induce neutralizing antibodies and control the disease. Here, we developed a GP5 protein-based ELISA for detecting antibodies against PRRSV. The overall yield of purified GP5 in E. coli flask culture was more than 45 mg/L cell culture. Western blot and IFA indicated that the GP5 protein was highly immunogenic. After optimization and validation with IDEXX PRRS using 566 clinical sera, the DSN, DSP, and accuracy of GP5-ELISA were 81.39%, 75.96%, and 80.39%, respectively. Besides, GP5-ELISA is highly specific, showing no cross-reactions with sera against other important swine pathogens. Hence, GP5 is a good diagnostic antigen and the GP5 protein-based ELISA has the potential to be used in the field
Źródło:
Polish Journal of Veterinary Sciences; 2016, 19, 3
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Teacher stress among public primary and secondary schoolteachers in Datong, a city of Shanxi Province, China: association between teacher stress and standardized workload
Autorzy:
Zhang, Xiaojuan
Guo, Jungang
Ma, Li
Xu, Ruijun
Wang, Jinfang
Yang, Yonghong
Shen, Hong
Powiązania:
https://bibliotekanauki.pl/articles/2203017.pdf
Data publikacji:
2023-05-23
Wydawca:
Instytut Medycyny Pracy im. prof. dra Jerzego Nofera w Łodzi
Tematy:
stress
occupational health
China
workload
primary and secondary schoolteachers
occupational health strategy
Opis:
Objectives The policy of the standardized workload has been implemented among primary and secondary schoolteachers in Shanxi Province. The aim of this cross-sectional cohort study is to assess teacher stress among primary and secondary schoolteachers in Datong, a city of Shanxi Province and the association between teacher stress and the quantified workload. Material and Methods Three hundred and fifty schoolteachers in 10 public primary schools, 187 schoolteachers in 6 secondary schools and 268 non-teachers in 21 education institutes were recruited. A single-item rating assessment of work-related stress was completed by using the Exposure to Job Stress measure with modification. The quantified workload included class size, teaching hours, and subjects. Descriptive and logistic regression analyses were carried out. Results In 805 participants, the pro- portion of primary and secondary schoolteachers with moderate stress was significantly greater. The results of Spearman’s correlation and logistic regression analyses showed that the occupations of the primary and secondary schoolteachers had higher stress risk. Further, the stratified results showed that among the primary schoolteachers, the independent stress risk factor was larger class size; while among the secondary schoolteachers, the stress associated factor was more weekly teaching hours. Conclusions After standardization of the workload, there remain higher levels of work stress among primary and secondary schoolteachers. Notwithstanding, the stress state in teachers is manageable and they may be faced with controllable stressors.
Źródło:
International Journal of Occupational Medicine and Environmental Health; 2023, 36, 2; 161-176
1232-1087
1896-494X
Pojawia się w:
International Journal of Occupational Medicine and Environmental Health
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Counterion effects on the alkali dissolution mechanism of quartz
Autorzy:
Yao, Yu-yun
Tang, Yun
Yang, Yong
Li, Guo-hui
Wu, Bo
Dai, Wen-zhi
Powiązania:
https://bibliotekanauki.pl/articles/2200337.pdf
Data publikacji:
2023
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
quartz
counterion
quantum chemistry
hydrolysis
mechanism
Opis:
In gold ore, quartz plays an important role in mineral formation by acting as the follower. Understanding counterion release, transport, and deposition in alkali solution is a prerequisite for evaluating the potential role of gold separate from quartz deposits in pretreatment. In this work, the aggregation, retention, and release of counterion in alkali solution media were investigated by kinetic research and pure mineral experiments, the correlation and mechanism of these processes were revealed by combining geochemical theory, interaction energy calculation, and quantum chemistry. The results showed that the retention and release of counterion were closely related to the dissolution and corrosion rate of quartz. The NH4+ and Fe2+ with higher mineral affinity reduced the quartz stability, and the dispersion stability and mobility of the quartz were greatly improved by an alkaline substance due to the enhancement of steric hindrance effects. Quantum chemical calculation results show that ammonium ion promotes the dissolution of quartz stronger than ferrous ion, which is mainly reflected in reducing the activation energy required for the formation of transition state (TS1), which can be verified by kinetic calculation. These findings provide essential insight into the extraction of gold coated by quartz as well as a vital reference for the experiment of gold-loaded quartz leaching in mineral processing.
Źródło:
Physicochemical Problems of Mineral Processing; 2023, 59, 1; art. no. 160038
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 19

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