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    Wyświetlanie 1-15 z 15
    Tytuł:
    Generalized Stokes parameters of random electromagnetic quasi-homogeneous beams on propagation
    Autorzy:
    Chen, J
    Xin, Y
    Chen, Y
    Chen, F
    Zhao, Q
    Powiązania:
    https://bibliotekanauki.pl/articles/174819.pdf
    Data publikacji:
    2013
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    electromagnetic
    quasi-homogeneous
    generalized Stokes parameters
    polarization
    Opis:
    The expressions for the elements of the on-axis and transverse generalized Stokes parameters of random electromagnetic quasi-homogeneous beams on propagation are presented and are used to study the polarization properties of the beams. Some typical numerical calculations of the on-axis and transverse Stokes parameters, polarization properties of the beams on propagation are illustrated. The results show that for different sources all the on-axis parameters are identical in the near field and keep fixed values in the far field. But the transverse parameters are affected greatly by the properties of the source even in the near field. We have also found that the spatial profiles of the transverse parameters remain unchanged upon propagation.
    Źródło:
    Optica Applicata; 2013, 43, 2; s. 205-216
    0078-5466
    1899-7015
    Pojawia się w:
    Optica Applicata
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Optical generation of ultra-wideband signals with a reconfigurable spectral notch-band
    Autorzy:
    Xiang, P.
    Chen, Y.
    Chen, D.
    Zhao, J.
    Powiązania:
    https://bibliotekanauki.pl/articles/174353.pdf
    Data publikacji:
    2014
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    ultra-wideband (UWB)
    ultra-wideband over fiber
    notch-band
    interference avoidance
    Opis:
    A novel method for optical generation of ultra-wideband signals with a reconfigurable spectral notch-band is proposed. In the proposed system, ultra-wideband signals are generated in the optical domain and an optical tunable delay line is deployed to introduce a notch-band to the spectral profile of the generated ultra-wideband signals, which can effectively avoid the signal interference between ultra-wideband signals and pre-planned narrowband wireless signals used in wireless local area networks (WLAN). A theoretical model describing the proposed system is derived; the optical generation and fiber transmission of ultra-wideband signals with a reconfigurable notch-band are demonstrated via computer simulations.
    Źródło:
    Optica Applicata; 2014, 44, 3; 411-419
    0078-5466
    1899-7015
    Pojawia się w:
    Optica Applicata
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Spectral degrees of cross-polarization of stochastic anisotropic electromagnetic beams in modified non-Kolmogorov atmospheric turbulence
    Autorzy:
    Chen, F.
    Chen, J.
    Zhao, Q.
    Chen, Y
    Xin, Y.
    Li, J.
    Pan, H.
    Powiązania:
    https://bibliotekanauki.pl/articles/174614.pdf
    Data publikacji:
    2013
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    quasi-homogenous source
    modified non-Kolmogorov turbulence
    generalized Stokes parameters
    Opis:
    Based on the extended Huygens–Fresnel principle, variations in generalized Stokes parameters of stochastic anisotropic electromagnetic beams propagating through modified non-Kolmogorov atmospheric turbulence have been analyzed. The changes in generalized Stokes parameters with different turbulence parameters and source parameters were analyzed first. After that, the distributions of the spectral degrees of cross-polarization (SDCP) of isotropic beams and anisotropic beams were simulated. The results show that the profiles of distribution of SDCP of these two kinds of beams are very different in the near field, and will fluctuate through the propagation in atmospheric turbulence, but at last, when the propagation distance is long enough, the difference in the source makes a slight difference in the final profiles of SDCP in the output plane. They mainly depended on the turbulence perturbation, and in the weak turbulence, the profiles of final distribution show more flatter features.
    Źródło:
    Optica Applicata; 2013, 43, 4; 773-783
    0078-5466
    1899-7015
    Pojawia się w:
    Optica Applicata
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effects of colloidal montmorillonite particles on froth flotation of graphite, galena and fluorite
    Autorzy:
    Chen, T.
    Zhao, Y.
    Li, H.
    Song, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/110589.pdf
    Data publikacji:
    2017
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    montmorillonite
    graphite
    galena
    fluorite
    slime coating
    entrainment
    Opis:
    The effect of colloidal montmorillonite (MMT) on froth flotation of graphite, galena and fluorite was investigated in this work. The results showed that the presence of sufficient amount of colloidal MMT particles in the mineral slurry would be detrimental of flotation by reducing the recovery of minerals. This observation was attributed to slime coating of MMT on the coarse valuable mineral particles and entrainment of MMT particles in the froth product together with water in the triangle froth zones. The former would reduce the recovery of the valuable minerals because of hydrophilic MMT coating. The latter would decrease the concentrate grade. The degree of slime coating depended on slurry pH, while the degree of entrainment was closely related to water recovery. It was also found that slime coating was a dominant factor in mineral flotation in acidic pH regions in the presence of colloidal MMT particles.
    Źródło:
    Physicochemical Problems of Mineral Processing; 2017, 53, 2; 699-713
    1643-1049
    2084-4735
    Pojawia się w:
    Physicochemical Problems of Mineral Processing
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The selective depression effect of sodium hexametaphosphate on the separation of chlorite and specularite
    Autorzy:
    Zhao, Fugang
    Yu, Xiankun
    Gao, Xiangpeng
    Li, Mingyang
    Chen, Xiangxiang
    Powiązania:
    https://bibliotekanauki.pl/articles/24085963.pdf
    Data publikacji:
    2023
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    flotation
    depressant
    chlorite
    specularite
    adsorption
    Opis:
    Flotation is the most known beneficiation method for the separation of complex and refractory iron ores. As a typical iron-containing silicates, it is difficult to separate chlorite from specularite, because of the similar surface physicochemical properties. In this study, the selective depression effect of sodium hexametaphosphate (SHMP) was conducted via the cationic micro-flotation. The surface adsorption mechanism between SHMP and the two mineral surface was explored through surface adsorption amount tests, Zeta-potential measurements, Fourier transform infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS) analyses. The micro-flotation results indicated that SHMP could selectively depress around 90% of chlorite, while its effect on the floatability of specularite was negligible (<20% depressing). The surface adsorption amount tests, Zeta-potential measurements analysis demonstrated that SHMP selectively adsorb on chlorite surface while on the surface of specularite is feeble. The further surface adsorption analysis via FT-IR and XPS proved that SHMP selective adsorption occurred on the chlorite surface mainly by chemisorption mainly through the chelation reaction between O in the phosphate groups of SHMP molecular and metal ions on surface of chlorite.
    Źródło:
    Physicochemical Problems of Mineral Processing; 2023, 59, 2; art. no. 166495
    1643-1049
    2084-4735
    Pojawia się w:
    Physicochemical Problems of Mineral Processing
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Influence of dispersion slope on soliton spectral tunneling in photonic crystal fiber
    Autorzy:
    Yang, Yunxia
    Yang, Hua
    Tong, Xiongfeng
    Zhao, Saili
    Chen, Shuyuan
    Powiązania:
    https://bibliotekanauki.pl/articles/2033951.pdf
    Data publikacji:
    2021
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    soliton spectral tunneling
    supercontinuum generation
    dispersion slope
    Opis:
    We report a numerical investigation of how the dispersion slope affects the soliton spectral tunneling (SST) in a photonic crystal fiber with three zero dispersion wavelengths. It is discovered that a larger dispersion slope makes group-velocity mismatch between the initial soliton and the transferred wave thereby suppressing the SST effect, while a proper decrease of the dispersion slope enhances the SST effect to widen a supercontinuum range. Besides, we find a soliton-like leaking dispersion wave, which can sustain information and energy for a short time within a particular spectral range.
    Źródło:
    Optica Applicata; 2021, 51, 3; 415-427
    0078-5466
    1899-7015
    Pojawia się w:
    Optica Applicata
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Defect solitons supported by kagome photonic lattices in biased photovoltaic-photorefractive crystals
    Autorzy:
    Hui, J.
    Lu, K.
    Zhao, C.
    Gao, L.
    Chen, W.
    Powiązania:
    https://bibliotekanauki.pl/articles/173797.pdf
    Data publikacji:
    2018
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    defect solitons
    photonic lattices
    photorefractive nonlinearity
    nonlinear optics
    Opis:
    We report that defect solitons can be supported by kagome photonic lattices with a defect in biased photovoltaic-photorefractive crystals. For a positive defect, these defect solitons exist only in the semi-infinite bandgap and are stable in the low power region but unstable in the high power region. For a negative defect, these defect solitons exist in both of the semi-infinite bandgaps and the first bandgap. In the semi-infinite bandgap, low-power defect solitons are stable when the negative defect depth is low and unstable when the negative defect depth is high, moderate-power defect solitons are stable when the negative defect depth is high, and high-power defect solitons are unstable for all the negative defect depths. In the first bandgap, defect solitons are stable in all the power regions when the negative defect depth is low. When the negative defect depth is high, defect solitons are stable in the high power region and unstable in the low power region. On the other hand, these defect solitons are those studied previously in kagome photonic lattices with a defect in biased non-photovoltaic-photorefractive crystals when the bulk photovoltaic effect is negligible and those in kagome photonic lattices with a defect in photovoltaic-photorefractive crystals when the external bias field is absent.
    Źródło:
    Optica Applicata; 2018, 48, 3; 349-359
    0078-5466
    1899-7015
    Pojawia się w:
    Optica Applicata
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Influence of fenugreek-gum and particle size on performance of talc flotation
    Autorzy:
    Gu, G.
    Mo, C.
    Zhao, K.
    Chen, Z.
    Wang, X.
    Powiązania:
    https://bibliotekanauki.pl/articles/109940.pdf
    Data publikacji:
    2018
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    talc
    particle size
    fenugreek-gum
    depression
    flocculation
    Opis:
    Talc usually exists as a gangue mineral in copper-nickel sulfide, molybdenite etc. In order to separate precious metals, naturally hydrophobic talc should be depressed effectively in flotation process. The effect of fenugreek-gum (FG) on the flotation performance of talc with different particle sizes was studied. The depression mechanism was investigated extensively through tests of flotation, adsorption and zeta potential, as well as infrared spectroscopy and laser particle size analysis. Flotation results indicated that the FG had a strong depression ability for talc with the particle size of -0.074 + 0.037 mm, -0.037 mm and -0.010 mm when proper dosage of FG was added. The coarse talc was completely depressed by 2.5 mg/ dm3 FG. When the particle size decreased, more FG was required to obtain the maximum depressing effect, which was verified by adsorption tests. FG reduced the electronegativity on the talc surface by chemical adsorption, and flocculation of talc powders caused a high efficient depressing effect.
    Źródło:
    Physicochemical Problems of Mineral Processing; 2018, 54, 3; 1026-1033
    1643-1049
    2084-4735
    Pojawia się w:
    Physicochemical Problems of Mineral Processing
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Comparison study of crystal and electronic structures for chalcopyrite $(CuFeS_2)$ and pyrite $(FeS_2)$
    Autorzy:
    Li, Yuqiong
    Liu, Yingchao
    Chen, Jianhua
    Zhao, Cuihua
    Cui, Weiyong
    Powiązania:
    https://bibliotekanauki.pl/articles/1448811.pdf
    Data publikacji:
    2021
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    chalcopyrite
    pyrite
    crystal structures
    electronic structures
    Opis:
    Chalcopyrite $(CuFeS_2)$ and pyrite $(FeS_2)$ are commonly associated with each other, and they both belong to semiconductor minerals. The difference in crystal and electronic structures is an important factor for their flotation separation. Using the density functional method (DFT) combined with Hubbard U correction, their crystal and electronic properties are comparatively studied. The calculated results suggest that the use of antiferromagnetic calculations and Hubbard U correction are very important to the accuracy of the chalcopyrite results. Antiferromagnetic calculations combined with a U value of 2.0 eV on chalcopyrite show a band gap of 0.53 eV, which is very consistent with the experimental results of ~0.5 eV. The density of states (DOS) and Mulliken bond population results indicate that stronger hybridization between Fe 3d and S 3p states in chalcopyrite than in pyrite leads to a stronger covalency of Fe-S bonds in chalcopyrite, causing a reduction in the spin magnetic moment (3.5 μB) from the ideal value. In addition, the greater covalency of bonds in chalcopyrite results in greater hydrophobicity of chalcopyrite than pyrite. The DOS results suggest that S has similar electronic properties in pyrite and chalcopyrite. The oxidation states of Fe and Cu ions in chalcopyrite are discussed based on the coordination field theory according to the calculation results, which confirms an oxidation state of $Fe^{3+}Cu^{1+}S_2$.
    Źródło:
    Physicochemical Problems of Mineral Processing; 2021, 57, 1; 100-111
    1643-1049
    2084-4735
    Pojawia się w:
    Physicochemical Problems of Mineral Processing
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The effect of a novel depressant on the separation of talc and copper –nickel sulfide ore
    Autorzy:
    Gu, Guohua
    Chen, Zhixiang
    Zhao, Kaile
    Song, Siyu
    Li, Shuangke
    Wang, Chongqing
    Powiązania:
    https://bibliotekanauki.pl/articles/110492.pdf
    Data publikacji:
    2019
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    Sodium alginate
    talc
    copper–nickel sulfide
    polysaccharide depressant
    flotation
    Opis:
    This paper researched the influence of the polysaccharide polymer sodium alginate (SAG) on the depression of talc at a fixed room temperature about 25 °C through micro flotation and batch flotation experiments, zeta potential and contact angle measurements as well as infrared spectroscopy analysis. The flotation results displayed that the SAG had a significant influence on the flotation of talc but less influence on sulphide flotation. Compared with the depressant carboxymethyl cellulose (CMC) and guar gum, using of the SAG gave the highest copper recovery. It could not only eliminate a talc removal step, but also significantly decrease in the depressant consumption by half at least. Sodium alginate apparently adsorbs on the talc surface and promotes hydrophilization, as revealed by contact angle tests (contact angle decreased from 75 to 33° after treating with SAG). It is demonstrated that the SAG obviously absorbed at the surface of talc but rarely for chalcopyrite through the results of zeta potential measurements and infrared spectroscopy analysis.
    Źródło:
    Physicochemical Problems of Mineral Processing; 2019, 55, 1; 116-127
    1643-1049
    2084-4735
    Pojawia się w:
    Physicochemical Problems of Mineral Processing
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Electrical neutralization ability of polyaluminum chloride (PACl) coagulants with different OH–/Al3+ ratios by fluorescence quenching effect
    Autorzy:
    Chi, Fung Hwa
    Cheng, Wen Po
    Yu, Ruey Fang
    Chen, Zhao Feng
    Powiązania:
    https://bibliotekanauki.pl/articles/207968.pdf
    Data publikacji:
    2020
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    stała Sterna-Volmera
    polichlorek glinu
    kwas humusowy
    fluorescencja
    Stern-Volmer constant
    polyaluminum chloride
    humic acid
    fluorescence
    Opis:
    The electrical neutralization ability of polyaluminum chlorides (PACls) with respect to humic acid was investigated by the fluorescence quenching method. The Stern–Volmer constant (Kq) at various pH and coagulation doses was determined for polyaluminum chlorides (PACl-B) of various basicities (B, B = [OH–]/[Al]). The experimental results show that under acidic conditions, the order of Kqvalues of PACl-B is PACl-2.5 > PACl-2.3 > PACl-1.5 > AlCl3. In solutions of pH = 7, the order of Kqvalues is PACl-1.5 > PACl-2.3 > PACl-2.5 > AlCl3. When pH > 7, aluminum ions are rapidly hydrolyzed, thus PACls of various basicities generally do not show capacity for electrical neutralization with humic acid. At pH = 6, all PACls-B obtain the maximum Kq values, indicating that humic acid and PACl-Bcoagulation process is less affected by H+ or OH– ions, and produces the best electrical neutralization ability. Compared to the past method of using surface potential as a means of determining the ability of neutralization of coagulation, the results of this study show that the Kq value of the quenching effect can reduce the experiment complexity.
    Źródło:
    Environment Protection Engineering; 2020, 46, 2; 25-39
    0324-8828
    Pojawia się w:
    Environment Protection Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Feasibility study on preparation of magnesium titanate in carbonthermic reduction of vanadium titanomagnetite concentrates
    Autorzy:
    Chen, Chao
    Sun, Ti-Chang
    Kou, Jue
    Wang, Xiao-Ping
    Zhao, Yong-Qiang
    Powiązania:
    https://bibliotekanauki.pl/articles/110181.pdf
    Data publikacji:
    2019
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    vanadium titanomagnetite
    carbonthermic reduction
    magnesium titanate
    formation mechanism
    Opis:
    Effect of temperature and Mg:Ti ratio on phase composition and microstructure of reduced pellets was investigated to verify the feasibility of preparation of magnesium titanate by adding MgO in carbonthermic reduction of the vanadium titanomagnetite concentrates (VTC). Thermodynamic analysis results showed that magnesium titanate is more easily generated than FeTi2O5 or TiO2 by the reaction of FeTiO3 and MgO under the reductive atmosphere, which was confirmed by the discovery of magnesium titanate at roast experiment. It was found that the optimum conditions for reduction of VTC pellets were temperature of 1250 ºC and Mg:Ti ratio of 2, and the main phases of reduction product were metallic Fe and magnesium titanate (Mg2TiO4). However, trace iron impurities in Mg2TiO4 particles were found by energy-dispersive spectroscopy (EDS), so further purification is required.
    Źródło:
    Physicochemical Problems of Mineral Processing; 2019, 55, 2; 417-425
    1643-1049
    2084-4735
    Pojawia się w:
    Physicochemical Problems of Mineral Processing
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Experimental study on triboelectrostatic beneficiation of wet fly ash using Microwave Heating
    Autorzy:
    Li, H.
    Chen, Y.
    Zhang, X.
    Zhao, Y.
    Tao, Y.
    Li, C.
    He, X.
    Powiązania:
    https://bibliotekanauki.pl/articles/110399.pdf
    Data publikacji:
    2016
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    wet fly ash
    triboelectrostatic beneficiation
    microwave heating
    efficiency
    Opis:
    Triboelectrostatic beneficiation, as a physical method, of fly ash cannot only meet the technical requirements of fly ash application but also recycle of an unburned carbon as a useful energy source. The aim of this study was to investigate the feasibility of improving efficiency of triboelectrostatic beneficiation of wet fly ash using microwave heating. The wet fly ash with different moisture contents had an average loss-on-ignition of 12.56%. The fly ash samples were heated in a microwave oven before the experiments. The experimental conditions were electric field voltage of 40 kV and air flux ranging from 12 to 30 m3/h. The influence of the microwave heating on the wet fly ash triboelectrostatic beneficiation was discussed under the conditions of different microwave intensity and irradiation time. The results indicated that the removal rate and recycle rate of the unburned carbon showed a significant increase performance as the wet fly ash was processed by the microwave heating which was attributed to changes of moisture contents and dielectric constants caused by the microwave heating. The feasibility had been verified according to the experimental study on fly ash with different moisture contents. It can be concluded that the microwave heating process was efficiently applied for the wet fly ash triboelectrostatic beneficiation.
    Źródło:
    Physicochemical Problems of Mineral Processing; 2016, 52, 1; 328-341
    1643-1049
    2084-4735
    Pojawia się w:
    Physicochemical Problems of Mineral Processing
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Evaluation of ammonium citrate tribasic as a leaching reagent for lead-bearing ore
    Autorzy:
    Liu, Junbo
    Li, Shimei
    Zhao, Biao
    Deng, Jianying
    Huang, Lingyun
    Zhou, Yuanyuan
    Chen, Cong
    Liu, Quanjun
    Powiązania:
    https://bibliotekanauki.pl/articles/109649.pdf
    Data publikacji:
    2019
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    lead
    cerussite
    ammonium citrate tribasic
    leaching
    kinetics
    Opis:
    In this study, the leaching process of a lead-bearing ore, consisting mainly of cerussite, in an ammonium citrate tribasic medium was investigated. The parameters including temperature, reagent concentration, particle size, and stirring speed were examined. During leaching process, the lead conversion rate increased with an increase in reagent concentration, reaction temperature, and stirring speed, and a decrease in particle size. The results show that about 95% of lead content was extracted from the samples with particle size range of +75-96 μm after 21 min leaching in 1.25 mol/L ammonium citrate tribasic solution at 800 r/min and 40°C. It was found that the leaching reaction followed the shrinking core model. The results indicated that ammonium citrate tribasic could be used as an effective leaching reagent for extracting lead from lead oxide ore.
    Źródło:
    Physicochemical Problems of Mineral Processing; 2019, 55, 3; 689-700
    1643-1049
    2084-4735
    Pojawia się w:
    Physicochemical Problems of Mineral Processing
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Optimization of CNTs and SiO2 for thermostability and mechanical properties of PF microcapsules : used for self-healing of closed wall cracks in goaf
    Autorzy:
    Fu, Mingming
    Ma, Boyu
    Zhang, Yuanping
    Jia, Xinlei
    Chen, Lu
    Zhang, Yuping
    Sun, Kaidi
    Zhao, Guanning
    Wang, Mengyao
    Powiązania:
    https://bibliotekanauki.pl/articles/24085883.pdf
    Data publikacji:
    2023
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    PF microcapsule
    crack repair
    closed wall
    nanomaterials
    heat resistance
    brittleness
    Opis:
    Air leakage of closed wall in coal mine goaf would cause spontaneous combustion of remained coal. Most of measures to repair cracks are carried out after cracks are penetrated, which is not conducive to early prevention of spontaneous combustion. Repairing damage at the initial stage of cracking makes prevention effect to the best. Phenol-formaldehyde resin (PF) microcapsules embedded in closed wall to achieve self-healing of initial cracks, but the actual repair effect is often less than expected. PF microcapsules (PFM) of carbon nanotubes (CNTs) and silicon dioxide (SiO2) decorated shell for self-healing of closed wall cracks were prepared by in-situ polymerization. The effects of nanomaterials on morphology, chemical constitution, thermal performance and mechanical properties of PF microcapsules were characterized by scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and nanoindentation test. The test results indicated that nanomaterials were successfully introduced into the shell of PF microcapsules. The CNTs-SiO2@PF microcapsules were uniformly dispersed, the thermal decomposition was delayed, and the residual carbon was significantly increased, and the brittleness of PF microcapsules was significantly enhanced. The 0.2CNTs-SiO2@PF microcapsules (0.2CNTs-SiO2@PFM) had a uniform and full particle size, the initial decomposition temperature was 267.6℃, the residual mass was 41.3%, the maximum load on the capsule wall reached 94.79 mN, and the load dropped sharply after the capsule wall rupture. Finally, the self-healing mechanism of closed wall doped with microcapsules was discussed. The exploration of modified phenolic microcapsules provides a new idea for the repair of closed wall in goaf.
    Źródło:
    Physicochemical Problems of Mineral Processing; 2023, 59, 3; art. no. 170020
    1643-1049
    2084-4735
    Pojawia się w:
    Physicochemical Problems of Mineral Processing
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
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