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71.
The utilization of urban underground space (UUS) offers an effective solution to urban problems but may also negatively affect urban development. Therefore, UUS development needs better concerted guidelines to coordinate various urban systems and the multiple components of the underground world. Sustainable Development Goals (SDGs), which should be viewed as important yardsticks for UUS development, do not explicitly mention urban underground space, although many of them are affected by both the positive and negative consequences of its development. To fill this gap, this review lays the foundations of relevant UUS concepts and uses exemplary cases to reveal that 11 out of 17 SDGs can be linked with UUS uses. These linkages also manifest that land administration, integrated planning, architectural design, and construction technology are critical dimensions for increasing the contributions of UUS to the realization of SDGs. To achieve multi-disciplinary synergies among these four critical dimensions, a collaborative approach framework based on spatial data infrastructure is required. Thus, this work provides academics and practitioners with a holistic view of sustainable UUS development.  相似文献   
72.
Particle shape is one of the most important parameters in the design and optimization of fixed-bed processes. To address the impact of particle shape on methanol partial oxidation to formaldehyde over molybdate catalyst, packings of spheres, cylinders, rings, and trilobes are numerically generated. The generated packings are used to carry out resolved particle Computational Fluid Dynamics (CFD) simulations under industrial conditions. Pressure drop, voidage and velocity profiles, radial heat transfer, and local and overall conversion and selectivity results are presented. Despite their lower particle surface area, lower particle effectiveness and more uneven flow distribution than trilobes, and lower overall heat transfer coefficient than cylinders, rings had the best conversion and selectivity due to their balance between the factors. Three longer tubes of rings, rings and cylinders, and rings and trilobes are simulated and show a small gain in selectivity for the rings and trilobes.  相似文献   
73.
Silicon - Silicon based particles were prepared using tetraethoxysilane (TEOS) as a silica monomer, and low concentration of polyethylene oxide-polypropylene oxide block copolymer (pluronic) with...  相似文献   
74.
In this experimental work, plasma treatment of the active layer in the bulk heterojunction solar cells was studied. The active layers consisting of zinc oxide nanoparticles:polyaniline were spin-coated on indium tin oxide covered glasses then kept in the cold plasma medium for different treatment times. The J-V characteristics were considered under air mass 1.5G standard illumination, and variations of the open-circuit voltages and short circuit currents were studied under different treatment times. The results show that there is an optimum treatment time to improve the properties of the layers. In order to understand the origin of this effect, the Hall coefficient, along with ultraviolet-visible spectra were measured, and for studying the topological impact of plasma on the surface of the layers, atomic force microscopy and Fourier-transform infrared spectroscopy were considered. The measurements confirmed the time dependency of the open-circuit voltages and short circuit currents of the cells on the plasma treatment times. Atomic force microscopy of the layers shows the significant topological effects of the plasma treatments on the surface of the active layers for different treatment times.  相似文献   
75.
Arianpour  Farzin  Arianpour  Aslı Çakır  Aali  Behnam 《SILICON》2021,13(12):4381-4389
Silicon - Sodium hexa-fluorosilicate (Na2SiF6) is a synthetic inorganic material with distinguished chemical, thermal and optical properties. In this research, a pure sodium hexa-fluorosilicate...  相似文献   
76.
77.
Novel nanocomposite hydrogel pipes on the basis of polyvinyl alcohol and montmorillonite (MMT) clay were prepared via a cyclic freezing–thawing technique and designed for subsurface irrigation in the agricultural sector with extraordinarily reduced water consumption. The results showed that the prepared nanocomposite hydrogel pipes had an exfoliated morphology with improved mechanical and thermal properties. It was shown that the gel contents of nanocomposite hydrogel pipes were increased by increasing the loading level of MMT and, in contrast, the swelling and drying abilities decreased. The water permeation and irrigating performances of the prepared pipes were investigated at the laboratory scale by taking into account the effects of the MMT loading levels in nanocomposite hydrogels and the thickness of pipes. The results indicated a significant decrease in water consumption in nanocomposite hydrogel pipes compared to the pure hydrogel pipe. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48631.  相似文献   
78.
The Journal of Supercomputing - For a natural number n, let $$S_n$$ denote the symmetric group on n letters. Let $$\textit{SEP}_n$$ be the Cayley graph $$\text {Cay}(S_n,\{\sigma ,\sigma ^{-1},\tau...  相似文献   
79.
Journal of Scheduling - Nowadays, electricity consumption in industrial and domestic sectors is growing increasingly. In recent years, due to the expansion of consumption and increased concern...  相似文献   
80.
Dominant optic atrophy, Kjer type, is an autosomal dominant disorder causing progressive loss of visual acuity and colour vision from early childhood. The gene (OPA1) has variable expressivity, a penetrance of 0.98, and the locus has been localised to 3q28-29. We have genotyped nine British families with the disease using 12 polymorphic microsatellite markers from this region. Linkage and haplotype analysis shows the OPA1 gene to be located in a 2.3 cM interval between markers D3S1601 and D3S2748. One family showed no evidence of linkage with the chromosome 3 markers, suggesting for the first time that locus heterogeneity for this disease may exist, although exclusion for linkage is based on unaffected subjects. In addition, analysis of recombinants has enabled us to order the 12 markers along chromosome 3.  相似文献   
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