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91.
Investigation into time dependent long-term performance of Prefabricated Vertical Drains (PVDs) combined with vacuum consolidation in thick deposits of clay has been extremely limited. Predicting both settlements and excess pore pressures in such cases has become increasingly challenging when time duration is long-term, e.g. several years. In discussing such matter, finding a suitable model to predict the long-term performance is inevitable. Elasto-plastic analysis models such as Cam-Clay cannot predict long-term time-dependent deformational behaviour in soft soils. In this technical note, a Biot type fully-coupled creep-based elastic viscoplastic (EVP) finite element (FE) numerical model has been extended for application in vacuum consolidation. The vacuum consolidation section of the embankment constructed in Ballina, New South Wales, Australia (hereafter referred as Ballina embankment), is analysed using the model through a unit cell analysis and the numerical predictions are compared with field performance monitoring data up to 1200 days (>3 years). The proposed analysis method for PVD combined with vacuum consolidation involving an EVP model is found to be capable of predicting both short-term and long-term deformational behaviours. Predictions are improved when an exponential function is used for the secondary compression index in the EVP model. Comparison has also been carried out at another location in the embankment where the foundation clay thickness was different to check the precision of the methodology and for better understanding of ground settlement behaviour. Details of the analysis methodology and its validation against field performance data are presented in this note. 相似文献
92.
T. A. Tsyganova D. S. Shevchenko O. S. Magomedova O. V. Rakhimova 《Glass Physics and Chemistry》2019,45(4):298-301
The results of studying the structural parameters and strength characteristics of a bioactive membrane are presented. The membrane was obtained based on high-silica glass via modification with silicon polyoxomolybdate. The membrane strength characteristics were simulated under conditions of the maximum pressure of a vacuum water-jet pump of 300 kPa. 相似文献
93.
Subha Balakrishnan Varun Prasath Padmanabhan Ravichandran Kulandaivelu T.S. Sankara Narayanan Nellaiappan Suresh Sagadevan Suriati Paiman Faruq Mohammad Hamad A. Al-Lohedan Prasanna Kumar Obulapuram Won Chun Oh 《Ceramics International》2021,47(4):5061-5070
Hydroxyapatite (HAP) is the naturally occurring mineral form of calcium apatite and the most studied material as a bone substituent. Considering HAP's inherent properties, this study explored changes in HAP's characteristics from doping with other metals such as Fe. To form pure HAP and Fe-HAP with different amounts of Fe, we used the hydrothermal approach, and the composites that formed were thoroughly analyzed for their crystallinity, surface bonding, morphology, magnetic behavior, mechanical strength, biocompatibility, hemocompatibility, and in vitro cytotoxicity. The powder XRD studies confirmed the samples' crystallinity, and the lowest crystalline size was 19.7 nm in 10Fe-HAP. The FTIR analysis confirmed the formation of HAP by the hydroxyl, phosphate, and carbonate groups. The FESEM demonstrated that the morphology of the pure HAP was rod-shaped, which transformed into spheres after Fe doping. The EDS analysis confirmed the successful formation of HAP and Fe-HAP composites. The magnetic studies indicated the diamagnetic behavior of the pure HAP, while the Fe-doped HAPs had a superparamagnetic nature with saturation magnetizations (Ms) of 2Fe-HAP, 4Fe-HAP, and 10Fe-HAP at 0.0062, 0.0092, and 0.029 emu/g respectively. Assessment of the mechanical properties, biocompatibility, hemocompatibility, and cytotoxicity indicated that the Fe-doped HAPs were superior to the pure HAP, and among the Fe-HAPs, the 10Fe-HAP) had the highest amount of Fe and the best characteristics. The studies also indicated that Ca2+ interactions influenced the cells via HAP doping with that of Fe, equally increasing the physicochemical and biological properties. 相似文献
94.
Meysam Heydari Gharahcheshmeh Maxwell T. Robinson Edward F. Gleason Karen K. Gleason 《Advanced functional materials》2021,31(14):2008712
Engineering the texture and nanostructure to improve the electrical conductivity of semicrystalline conjugated polymers must address the rate-limiting step for charge carrier transport. In highly face-on orientation, the charge transport between chains within a crystallite becomes rate-limiting, which is highly sensitive to the π–π stacking distance and interchain charge transfer integral. Here, face-on oriented semicrystalline poly(3,4-ethylenedioxythiophene) (PEDOT) thin films are grown via water-assisted (W-A) oxidative chemical vapor deposition (oCVD). Combining W-A with the volatile oxidant, antimony pentachloride, yields an optimized electrical conductivity of 7520 ± 240 S cm−1, a record for PEDOT thin films. Systematic control of π–π stacking distance from 3.50 Å down to 3.43 Å yields an electrical conductivity enhancement of ≈ 1140%. The highest electrical conductivity also corresponds to minimum in Urbach energy of 205 meV, indicating superior morphological order. The figure of merit for transparent conductors, σdc/σop, reaches a maximum value of 94, which is 1.9 × and 6.7 × higher than oCVD PEDOT grown without W-A and utilizing vanadium oxytrichloride and iron chloride oxidizing agents, respectively. The W-A oCVD is single-step all-dry process and provides conformal coverage, allowing direct growth on mechanical flexible, rough, and structured surfaces without the need for complex and costly transfer steps. 相似文献
95.
Wireless Personal Communications - This paper summarizes the ongoing research initiatives based on the advanced multiple access techniques towards the fifth generation (5G) wireless communication... 相似文献
96.
Bagraev N. T. Kukushkin S. A. Osipov A. V. Romanov V. V. Klyachkin L. E. Malyarenko A. M. Khromov V. S. 《Semiconductors》2021,55(2):137-145
Semiconductors - A cycle of experimental investigations is carried out, specifically, the measurements and analysis of field dependences of the static magnetic susceptibility in samples of... 相似文献
97.
Skoblo T. S. Klochko O. Yu. Sidashenko O. I. Belkin I. L. Avtukhov A. K. Maltsev T. V. Deryabkina E. S. Kolpachenko N. M. 《Materials Science》2021,56(6):771-778
Materials Science - We study the causes and signs of degradation of cementite in chromium-nickel cast iron used for the production of massive forming rolls and the specific features of structural... 相似文献
98.
Prof. Andrea Baier Dr. Anne Kokel Dr. William Horton Ewa Gizińska Dr. Garima Pandey Prof. Ryszard Szyszka Prof. Béla Török Prof. Marianna Török 《ChemMedChem》2021,16(12):1927-1932
A set of novel hydrazone derivatives were synthesized and analyzed for their biological activities. The compounds were tested for their inhibitory effect on the phosphorylating activity of the protein kinase CK2, and their antioxidant activity was also determined in three commonly used assays. The hydrazones were evaluated for their radical scavenging against the DPPH, ABTS and peroxyl radicals. Several compounds have been identified as good antioxidants as well as potent protein kinase CK2 inhibitors. Most hydrazones containing a 4-N(CH3)2 residue or perfluorinated phenyl rings showed high activity in the radical-scavenging assays and possess nanomolar IC50 values in the kinase assays. 相似文献
99.
D.G. Krotkevich E.B. Kashkarov M.S. Syrtanov T.L. Murashkina A.M. Lider S. Schmiedeke N. Travitzky 《Ceramics International》2021,47(9):12221-12227
The paper describes the structure and properties of preceramic paper-derived Ti3Al(Si)C2-based composites fabricated by spark plasma sintering. The effect of sintering temperature and pressure on microstructure and mechanical properties of the composites was studied. The microstructure and phase composition were analyzed by scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively. It was found that at 1150 °C the sintering of materials with the MAX-phase content above 84 vol% leads to nearly dense composites. The partial decomposition of the Ti3Al(Si)C2 phase becomes stronger with the temperature increase from 1150 to 1350 °C. In this case, composite materials with more than 20 vol% of TiC were obtained. The paper-derived Ti3Al(Si)C2-based composites with the flexural strength > 900 MPa and fracture toughness of >5 MPa m1/2 were sintered at 1150 °C. The high values of flexural strength were attributed to fine microstructure and strengthening effect by secondary TiC and Al2O3 phases. The flexural strength and fracture toughness decrease with increase of the sintering temperature that is caused by phase composition and porosity of the composites. The hardness of composites increases from ~9.7 GPa (at 1150 °C) to ~11.2 GPa (at 1350 °C) due to higher content of TiC and Al2O3 phases. 相似文献
100.
Egorov A. F. Savitskaya T. V. Mikhailova P. G. 《Theoretical Foundations of Chemical Engineering》2021,55(2):225-252
Theoretical Foundations of Chemical Engineering - An analytical review of the state of multiproduct chemical plants has been proposed. A comprehensive analysis is made of works of Russian and... 相似文献