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Wyszukujesz frazę "Ding, Li" wg kryterium: Autor


Tytuł:
Sleep Snoring Sound Recognition Based on Wavelet Packet Transform
Autorzy:
Ding, Li
Peng, Jianxin
Zhang, Xiaowen
Song, Lijuan
Powiązania:
https://bibliotekanauki.pl/articles/31339924.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
snoring recognition
wavelet packet transform
feature selection
machine learning
Opis:
Snoring is a typical and intuitive symptom of the obstructive sleep apnea hypopnea syndrome (OSAHS), which is a kind of sleep-related respiratory disorder having adverse effects on people’s lives. Detecting snoring sounds from the whole night recorded sounds is the first but the most important step for the snoring analysis of OSAHS. An automatic snoring detection system based on the wavelet packet transform (WPT) with an eXtreme Gradient Boosting (XGBoost) classifier is proposed in the paper, which recognizes snoring sounds from the enhanced episodes by the generalization subspace noise reduction algorithm. The feature selection technology based on correlation analysis is applied to select the most discriminative WPT features. The selected features yield a high sensitivity of 97.27% and a precision of 96.48% on the test set. The recognition performance demonstrates that WPT is effective in the analysis of snoring and non-snoring sounds, and the difference is exhibited much more comprehensively by sub-bands with smaller frequency ranges. The distribution of snoring sound is mainly on the middle and low frequency parts, there is also evident difference between snoring and non-snoring sounds on the high frequency part.
Źródło:
Archives of Acoustics; 2023, 48, 1; 3-12
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Delay-dependent dissipative control for stochastic singular systems with state delay
Autorzy:
Ding, C.
Li, Q.
Powiązania:
https://bibliotekanauki.pl/articles/229379.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
stochastic singular system
dissipative control
delay-dependent
state delay
linear matrix inequalities (LMIs)
Opis:
The problem of delay-dependent dissipative analysis and control for stochastic singular systems with state delay is investigated in this paper. Delay-dependent dissipative condition for the stochastic singular systems with state delay is obtained by employing singular stochastic Lyapunov and LMI-based methods. Based on this condition, a delay-dependent dissipative controller is presented. A numerical example is provided to demonstrate the effectiveness of the proposed approach.
Źródło:
Archives of Control Sciences; 2013, 23, 3; 281-293
1230-2384
Pojawia się w:
Archives of Control Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optical coherence tomography image for automatic classification of diabetic macular edema
Autorzy:
Wang, Ping
Li, Jia-Li
Ding, Hao
Powiązania:
https://bibliotekanauki.pl/articles/1835815.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
diabetic macular edema
optical coherence tomography
transfer learning
fine-tuning
Opis:
Diabetic macular edema (DME) is the dominant reason of diabetic visual loss, so early detection and treatment of DME is of great significance for the treatment of diabetes. Based on transfer learning, an automatic classification method is proposed to distinguish DME images from normal images in optical coherence tomography (OCT) retinal fundus images. Features of the DME are automatically identified and extracted by the pre-trained convolutional neural network (CNN), which only involves fine-tuning the VGGNet-16 network without any user intervention. An accuracy of 97.9% and a sensitivity of 98.0% are acquired with the OCT images in the Duke data set from experimental results. The proposed method, a core part of an automated diagnosis system of the DME, revealed the ability of fine-tuning models to train non-medical images, allowing them can be classified with limited training data. Moreover, it can be developed to assist early diagnosis of the disease, effectively delaying (or avoiding) the progression of the disease, consequently.
Źródło:
Optica Applicata; 2020, 50, 4; 567-577
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Can Urban-rural Integration Decrease Energy Intensity? Empirical Study Based on China’s Inter-provincial Data
Czy integracja obszarów miejsko-wiejskich prowadzi do ograniczenia energochłonności? Przykład Chin
Autorzy:
Chen, Shuxing
Ding, Renzhong
Li, Biao
Powiązania:
https://bibliotekanauki.pl/articles/371003.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Komitet Człowiek i Środowisko PAN
Tematy:
urban-rural integration
urbanization
industrialization
technology
energy intensity
integracja obszarów miejsko-wiejskich
urbanizacja
industrializacja
technologia
energochłonność
Opis:
The paper discusses the mathematical relationship of Urban-rural integration and energy intensity based on the production function including capital, labor and energy. Then, the empirical analysis on how it affect energy intensity, on the basis of the static and dynamic panel model with China’s 30 provincial economic data in 2005-2014 years, using four estimation methods – FE, IV-FE, IV-GMM and MG. As part of integration, urbanization, industrialization and technology are found from the empirical results. Firstly, urbanization can significantly reduce energy intensity in short run, while the effect is positive in long term, as China didn’t lastly use the role in saving energy on the process of urbanization. Secondly, industrialization can effectively cut down energy intensity. Thirdly, it is worthy to pay more attention to the ability to improve energy efficiency and lower energy intensity of technology in short and long run.
W artykule przeanalizowano matematyczną zależność integracji obszarów miejsko-wiejskich i energochłonności opartej na funkcji produkcyjnej z uwzględnieniem kapitału, rynku pracy i energii. Jest to podstawą do analizy empirycznej odnoszącej się do tego, jak integracja wpływa na energochłonność, na bazie statycznych i dynamicznych paneli odnoszących się do 30 regionów w Chinach, uwzględniając dane z lat 2005-2014 i używając metod szacowania FE, IV-FE, IV-GMM i MG. Jako części procesu integracji, na podstawie danych empirycznych, wyróżniliśmy urbanizację, industrializację i stronę technologiczną. Okazało się, że po pierwsze urbanizacja może znacząco obniżyć energochłonność w krótkiej perspektywie czasowej, jednak korzyści pojawiają się po dłuższym czasie, ponieważ Chiny nie przywiązywały roli do oszczędzania energii w kontekście urbanizacji. Po drugie, industrializacja może efektywnie obniżyć energochłonność wykorzystywanych technologii i to zarówno w perspektywie krótko, jak i długoterminowej.
Źródło:
Problemy Ekorozwoju; 2018, 13, 1; 49-58
1895-6912
Pojawia się w:
Problemy Ekorozwoju
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Preparation and Properties of Low-Nitrogen Nitrocellulose by Alkaline Denitration
Autorzy:
Tao, Zhongan
Li, Shiying
Ding, Yajun
Xiao, Zhongliang
Powiązania:
https://bibliotekanauki.pl/articles/1062782.pdf
Data publikacji:
2020
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
waste
high-nitrogen nitrocellulose
denitration
nitrogen content
explosion heat
recycling
Opis:
Waste high-nitrogen nitrocellulose (NC) has always been disposed of as hazardous material for destruction, and has not been recycled as a resource. The present work describes how waste high-nitrogen NC may be converted to low-nitrogen NC via an alkaline denitration reaction between sodium hydrosulfide and the nitrate ester groups, in order to control and reduce the nitrogen content for industrial products. Scanning electron microscopy (SEM), infrared spectroscopy (FT-IR), 1H nuclear magnetic resonance spectroscopy (1H NMR) and X-ray diffraction (XRD) were used to detected the changes in the surface morphology and chemical structure of the NC samples. TG-DSC tests analyzed the decomposition temperature and the heat released on thermal decomposition, and the explosion heat was obtained by calorimetry. The results demonstrated that the denitration reaction does not destroy the skeletal structure of NC. Notably, the nitrogen content of NC may be reduced from 12.92 to 10.74%, generating the level for industrial products (N <12%). Moreover, NC samples with different nitrogen contents have similar decomposition trends and decomposition temperatures, but the heat released is gradually decreased and the explosion heat is significantly reduced, and confirms the successful partial removal of nitrate ester groups from NC. Therefore, the alkaline denitration affords a potential method for recycling waste high-nitrogen NC.
Źródło:
Central European Journal of Energetic Materials; 2020, 17, 4; 535-551
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of heating on thermal denaturation of several green vegetables suitable for dehydration
Autorzy:
Zhang, M.
Li, C.L.
Ding, X.L.
Powiązania:
https://bibliotekanauki.pl/articles/25723.pdf
Data publikacji:
2001
Wydawca:
Polska Akademia Nauk. Instytut Agrofizyki PAN
Tematy:
differential scanning calorimetry
dehydration
heating
thermal analysis
thermal denaturation
vegetable
green vegetable
Źródło:
International Agrophysics; 2001, 15, 3
0236-8722
Pojawia się w:
International Agrophysics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The depression mechanism on pyrite in a low-alkaline system with combined depressants : Experiment, HSC, DFT and ToF–SIMS studies
Autorzy:
Li, Suqi
Yuan, Jiaqiao
Ding, Zhan
Li, Jie
Yu, Anmei
Wen, Shuming
Bai, Shaojun
Powiązania:
https://bibliotekanauki.pl/articles/24085821.pdf
Data publikacji:
2023
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
pyrite
calcium hypochlorite
lime
depression
low alkaline system
Opis:
Depression of pyrite in a low-alkaline system has sparked soaring interests for the multi-metal sulfide minerals flotation recently. This study investigates effects of combined depressants (Ca(ClO)2 and CaO) on pyrite flotation with butyl xanthate (KBX). Micro-flotation experiments indicate that the addition of 200 mg/L combined depressants (a mass ratios of CaO to Ca(ClO) 2 of 2:3) and 1.0×10−3 mol/L KBX at pH 9.5 can effectively depresses the flotation of pyrite, and a minimum pyrite recovery rate of 12.5% is obtained. Basic thermodynamic evaluation results confirm the participation of Ca(ClO) 2 significantly decrease the negative Gibbs free energies of pyrite oxidation reaction. Besides, the calcium species (Ca(OH) 2, Ca2+ and Ca(Cl) 2) will spontaneously transform into CaCO3,and it is the ultimate dominant calcium species in the CO32- system. Density functional theory (DFT) results indicate that CaCO3 can chemically adsorb onto the pyrite surface with an adsorption energy of –671.13 kJ/mol. The O1 and Ca atoms mainly contribute to the bonding process and are responsible for the stable adsorption of CaCO3. ToF-SIMS results provide strong evidence that the combined depressants increase the amount of hydrophilic species and decrease dixanthogen adsorption onto the pyrite surface. The thickness of the whole formed hydrophilic species is approximately 50 nm. Semiquantitative amounts of hydrophilic species follow the order of hydroxy calcium>iron carbonyl>calcium carbonate. Overall, hydrophilic species repulse adsorption of dixanthogen and significantly reduce the flotation performance of pyrite.
Źródło:
Physicochemical Problems of Mineral Processing; 2023, 59, 3; art. no. 168454
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical simulations of linearly stratified flow past submerged bodies
Autorzy:
Ma, W.
Li, Y.
Ding, Y.
Hu, K.
Lan, L.
Powiązania:
https://bibliotekanauki.pl/articles/259150.pdf
Data publikacji:
2018
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
stratified flow
circular cylinder
internal wave
Suboff
equation of state
Opis:
In this study, a methodology was presented to predict density stratified flows in the near-field of submerged bodies. The energy equation in temperature form was solved coupled with momentum and mass conservation equations. Linear stratification was achieved by the definition of the density as a function of temperature. At first, verifications were performed for the stratified flows passing a submerged horizontal circular cylinder, showing excellent agreement with available experimental data. The ability of the method to cope with variable density was demonstrated. Different turbulence models were used for different Re numbers and flow states. Based on the numerical methods proposed in this paper, the stratified flow was studied for the real scale benchmark DAPRA Suboff submarine. The approach used the VOF method for tracing the free surface. Turbulence was implemented with a k − ω based Detached Eddy Simulation (DES) approach. The effects of submarine speed, depth and density gradient on the free surface wave pattern were quantitatively analyzed. It was shown that, with the increasing of the speed of the submarine, the wavelength and wave height of the free surface wave were gradually increasing. The wave height of the free surface wave was gradually reduced as the submarine’s depth increased. Relative to the speed and submarine depth, the changes of the gradient density gradient have negligible effects on the free surface wave field.
Źródło:
Polish Maritime Research; 2018, S 3; 68-77
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study on the dynamic development law of fissure in expansive soil under different soil thickness
Autorzy:
Guo, Jianhua
Ding, Gang
Wang, Hanhui
Li, Shichang
Dai, Zhangjun
Powiązania:
https://bibliotekanauki.pl/articles/28032105.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Opis:
Fissures are an important factor to induce slope instability of expansive soil channel, which destroys the integrity of soil mass and deteriorates soil mass. Currently, the research is limited to the fissures in the plane direction, and it is very important to reveal the development mechanism of fissures in expansive soils along the depth direction by studying the development law of fissures in expansive soils with different thicknesses. In this study, taking expansive soil on channel slope of the Middle Route Project of South-to-North Water Transfer as an example, crack expansion tests with thickness of 10 mm, 20 mm, 30 mm and 40 mm are carried out based on self-designed crack expansion test device. An innovative test method for volumetric fracturing rate is proposed and the following conclusions are drawn: (1) the later the cracking time of soil body is, the lower the water content of cracking and the higher the water content after stabilization when the soil body is thicker; (2) When the fissures develop in soils of different thicknesses, their plane fissure rate changes with time in accordance with the logistic law; (3) Volumetric fracturing increases significantly with thickness; (4) The development of fissures is the form of stress release of soil mass, and the release along depth direction is the main form for soil mass with large thickness. (5) It is of great significance to study the law of fracture development in depth direction for further exploring the mechanism of fracture propagation.
Źródło:
Archives of Civil Engineering; 2023, 69, 4; 519--534
1230-2945
Pojawia się w:
Archives of Civil Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characteristics and metal leachability of natural contaminated soil under acid rain scenarios
Autorzy:
Tan, Wenfa
Li, Yuan
Ding, Lei
Wang, Yachao
Li, Jiangxiang
Deng, Qinwen
Guo, Feng
Xiao, Xue
Powiązania:
https://bibliotekanauki.pl/articles/205435.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
heavy metal
soil pollution
fraction analysis
soil leaching
Opis:
Contamination of soil with heavy metals has become a worldwide environmental problem, and receives great attention. In this study, we aim to investigate soil pollution level affected by an industrial district nearby. The total amount of typical heavy metals in the soils (Hengyang Songmu Industrial Park, Hunan Province, China) was analyzed. In addition, the fraction analysis and laboratory simulation leaching via different pH rainwater was carried out to study the migration and transformation of heavy metals. The main results show that the contents of Cu, Zn, Pb, Cr and Cd in the samples were higher than the soil background values in Hunan Province. The heavy metals forms, analyzed by sequential extraction method, show that the proportion of the unstable form of Cd, Zn and Pb was more than 50%. Igeo values indicate that the heavy metal pollution degree of soil sample #5 at the investigated area is recorded in the order of Cd(6.42), Zn(2.28), Cu(1.82), Pb(1.63), and Cr(0.37). Cu, Zn, Pb, Cr and Cd in this area could pose a potential leaching risk to the environment which may affect the food chain and constitute a threat to human health. It would be necessary to take steps to stabilize and monitor the heavy metals in soil.
Źródło:
Archives of Environmental Protection; 2019, 45, 2; 91-98
2083-4772
2083-4810
Pojawia się w:
Archives of Environmental Protection
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of U-shaped two-step throttling groove parameters on cavitation erosion characteristics
Autorzy:
Jia, Wenhua
Liu, Yanyan
Yin, Chenbo
Li, Guo
Zhu, Dasheng
Ding, Shen
Powiązania:
https://bibliotekanauki.pl/articles/2055063.pdf
Data publikacji:
2021
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
avitation erosion
throttling groove
distribution coefficient
Opis:
Throttling usually occurs when a fluid passes through an orifice, sometimes even severe cav- itation erosion may occur. In this study, the equation for the cavitation index of a throttling valve was proposed and the cavitation erosion area in the throttle valve was found to change its position with the orifice opening (X). Cavitation features of singular and two-port se- ries throttling grooves were characterized by defining cavitation indexes σ1and σ2, because the cavitation index-σ can determine the occurrence and intensity of cavitation. Then the indexes σ1 and σ2 included internal geometric parameters and external pressure boundaries were obtained, and cavitation indexes curves σ1-X and σ2-X were also plotted. From the curves of the cavitation index, it was observed that cavitation concentration section also would transfer with opening X changes in the U-shaped groove. The depth of the U-shaped groove had a more evident impact on cavitation, whereas the effect of width on cavitation erosion was not so obvious. The intensity of cavitation erosion when the fluid flowed into the orifice section of the U-shaped groove was always larger than that when the fluid flowed away.
Źródło:
Journal of Theoretical and Applied Mechanics; 2021, 59, 4; 529--538
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigations on soluble starch as the depressant of hematite during flotation separation of apatite
Autorzy:
Bai, Shaojun
Ding, Zhan
Fu, Xianyu
Li, Chunlong
Lv, Chao
Wen, Chao
Powiązania:
https://bibliotekanauki.pl/articles/110115.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
soluble starch
depressant
hematite
apatite
FTIR
XPS
Opis:
In this paper, soluble starch was studied as a depressant of hematite during flotation separation of apatite using sodium oleate as a collector. Surface charge measurement, soluble starch adsorptions, Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) were used to understand the interaction mechanisms between minerals (hematite and apatite) and soluble starch. The results indicated that chemical interaction between hematite and soluble starch was present, and supported the bonding of hydroxyl, while physical adsorption of soluble starch molecules with apatite occurred. Results of micro-flotation studies suggested that soluble starch was considered as a selective depressant for hematite. The maximum recovery difference between hematite and apatite of 77.5% was obtained with 40 mg/dm3 soluble starch. The flotation experiment results of natural iron ore showed that flotation indexes with 59.73% Fe, iron recovery of 81.5% and 75.68% of dephosphorization ratio were achieved at a soluble starch dosage of 60 mg/dm3. However, a higher dosage of soluble starch addition caused the difficulty for flotation separation of apatite from hematite. Our results provided theoretical basis for the flotation separation of apatite from iron oxide ores.
Źródło:
Physicochemical Problems of Mineral Processing; 2019, 55, 1; 38-48
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An innovative flotation technology for the lime-depressed pyrite recovery from copper sulphide ore via acid mine drainage (AMD) activation
Autorzy:
Yuan, Jiaqiao
Ding, Zhan
Bi, Yunxiao
Li, Jie
Wen, Shuming
Bai, Shaojun
Powiązania:
https://bibliotekanauki.pl/articles/2175438.pdf
Data publikacji:
2022
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
copper sulfide ore
acid mine drainage (AMD)
lime-depressed-pyrite
activator
hydrophilic species
Opis:
In this study, an innovative flotation technology consisted of Cu differential flotation with high alkali lime and pyrite recovery with acid mine drainage (AMD) activation was investigated for the cleaner beneficiation of the copper sulfide ore. Flotation test results showed that H2SO4 -CuSO4 and AMD could effectively activate the pyrite flotation with SBX collector. Moreover, the recovery of S concentrate is increased by 5.33% in the AMD system. Adsorption amount results of SBX collector indicated that the hydrophilic species (Ca2+, CaOH+ and FeOOH) were formed on the pyrite surfaces in the high alkali lime craft (pH=11.3) and degraded the interaction between SBX and pyrite surfaces. AMD can effectively clear off the hydrophilic calcium species and the copper ions originated from the AMD absorb onto the pyrite surfaces, facilitating the SBX collector adsorption. Composition analysis results of tailings water confirmed that the tailing water obtained by the AMD flotation system was more desirable to be recycled in the Cu differential flotation due to its higher pH value (8.7). The present study provides a novel approach for the treatment of AMD, and has the vital practical significance for the emission reduction of AMD and the increase of beneficiation profits.
Źródło:
Physicochemical Problems of Mineral Processing; 2022, 58, 6; art. no. 152609
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Internal Friction of Phase Transformations Observed Around Room Temperature in Ga-In-Sn Eutectic Alloys
Tarcie wewnętrzne przemian fazowych obserwowanych przy temperaturze pokojowej w eutektycznym stopie Ga-In-Sn
Autorzy:
Jin, M.
Li, Q.
Ying, R.
Lu, X.
Jin, X.
Ding, X.
Powiązania:
https://bibliotekanauki.pl/articles/352781.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Ga-In-Sn alloy
internal friction
liquid-liquid transition
stop Ga-In-Sn
tarcie wewnętrzne
wstępne krzepnięcie
Opis:
The phase transformation phenomena in eutectic Ga-In-Sn alloys around room temperature are studied by thermal analysis, internal friction, and in-situ XRD methods. The results show that in addition to the solidification transformation, a novel the so-called ‘pre-solidification’ phase transition, demonstrating first-order feature, is observed prior to the crystallization during cooling. The internal friction increases when the ‘pre-solidification’ effect occurs. The shear modulus increases until crystallization. An internal friction peak is attributed to the melting process observed during heating. The mechanism of the ‘pre-solidification’ transformation in Ga-In-Sn eutectic alloy is discussed.
Zjawiska przemian fazowych w eutektycznych stopach Ga-In-Sn, około temperatury pokojowej, badane są metodami analizy termicznej, tarcia wewnętrznego i XRD in-situ. Wyniki pokazują, że w dodatku do przemiany krzepnięcia, nowa przemiana tzw. „wstępne krzepnięcie”, o charakterze przemiany pierwszego rzędu, obserwowana jest przed krystalizacją podczas chłodzenia. Tarcie wewnętrzne zwiększa się, gdy występuje „wstępnie krzepnięcie”. Moduł sprężystości poprzecznej zwiększa się aż do krystalizacji. Wewnętrzny pik tarcia przypisany jest do topienia obserwowanego podczas ogrzewania. Omówiono mechanizm przemiany „wstępnego krzepnięcia” w eutektycznym stopie Ga-In-Sn.
Źródło:
Archives of Metallurgy and Materials; 2015, 60, 3A; 2097-2100
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Microcellular Oblate Propellant with Skin-core Structure Deterred by Poly(neopentanediol adipate)
Autorzy:
Ding, Yajun
Ying, Sanjiu
Xiao, Zhongliang
Wu, Wenlong
Li, Chunzhi
He, Yun
Powiązania:
https://bibliotekanauki.pl/articles/358225.pdf
Data publikacji:
2020
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
SC-CO2
microcellular oblate propellant
skin-core structure
poly(neopentanediol adipate) deterring
combustion performance
Opis:
In order to solve the issues of high muzzle flash, smoke, residue, migration rate and carcinogenicity of double-base oblate propellants deterred by dibutyl phthalate (DBP), skin-core structure microporous oblate propellants to replace DBP deterring technology were fabricated in the present work by supercritical carbon dioxide (SC-CO2) foaming technology. Poly(neopentanediol adipate) (NA) was employed as the deterrent to modify the combustion properties because of ist lower migration rate in storage. Scanning electron microscopy (SEM) was used to observe the morphology of the microporous oblate propellants generated by different processing conditions, and the combustion properties were investigated by closed bomb tests. The SEM images indicated that the skin region displayed smaller cell diameters and lower cell density compared with cells in the core region. The closed bomb tests demonstrated that it was feasible to adjust the progressive combustion performance by controlling the skin-core structure and the NA deterred layer. The burning time values of the original, the microcellular, and the NA deterred samples were 3.45, 2.14, and 4.20 ms, respectively. Microcellular oblate propellants, with a skin-core structure foamed by SC-CO2 and deterred by NA, provides a novel and promising method to realize progressive combustion performance.
Źródło:
Central European Journal of Energetic Materials; 2020, 17, 1; 49-65
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł

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