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Cavitation happening inside an inclined V-shaped corner is a common and important phenomenon in practical engineering. In the present study, the lattice Boltzmann models coupling velocity and temperature fields are adopted to investigate this complex collapse process. Based on a series of simulations, the fields of density, pressure, velocity and temperature are obtained simultaneously. Overall, the simulation results agree with the experiments, and they prove that the coupled lattice Boltzmann models are effective to study cavitation bubble collapse. It was found that the maximum temperature of bubble collapse increases approximately linearly with the rise of the distance between the single bubble center and the corner. Meanwhile, the velocity of the micro-jet increases and the pressure peak at the corner decreases correspondingly. Moreover, the effect of angle of the V-shaped wall on the collapse process of bubbles is similar to the effect of distance between the single bubble center and the corner. Moreover, with the increase in bubble radius, the maximum temperature of bubble collapse increases proportionally, the starting and ending of the micro-jet are delayed and the pressure peak at the corner becomes larger and also is delayed. In the double bubble collapse, the effect of distance between two bubble centers on the collapse process of bubbles is discussed in detail. Based on the present study, appropriate measures can be proposed to prevent or utilize cavitation in practical engineering. [ABSTRACT FROM AUTHOR]

Thermal comfort in outdoor spaces is of vital importance to human health and well-being, and affects the livability of cities. In a humid-hot region with elevated temperatures, it is difficult to improve the thermal experience of urban residents by changing objective conditions such as the microclimate. This study created a set of experience indices in different dimensions including visual, auditory, and olfactory perceptions and psychological cognitions, to explore the influencing factors and mechanisms of visitor's thermal comfort in an urban park. We found that visual, auditory, and olfactory experience indices and psychological cognition indices were both strongly correlated with thermal comfort (Pearson correlation coefficients were above 0.3). By analyzing a survey data with a structural equation model, we found that Visual, auditory, and olfactory experiences have a complete, mediating effect on thermal comfort. Explicitly, visual, auditory, and olfactory perceptions affect thermal comfort through two mediating variables: thermal sensation and psychological cognitions. In turn, thermal sensation and psychological cognitions have a direct effect on visitor's thermal comfort. Psychological cognitions has the largest direct effect on thermal comfort. Quantitatively, a 1-unit increase in psychological cognitions produces an increase of 0.601 units in thermal comfort. A potential approach is to improve multisensory modalities that affect necessary sensory perception and psychological cognitions of visitors. The findings of this study provide a valuable reference for the planning and design of recreational spaces in humid-hot regions and for the studies of outdoor thermal comfort. [ABSTRACT FROM AUTHOR]

Based on the theory of landsenses ecology, this paper makes a detailed analysis of the architecture pattern of 'The House of Hundred Rooms'(HHR) in the East Dragon Village, a traditional ancient Chinese village, so as to provide a reference for the research on reasonable land use and sustainable development in modern times. By the principle of the vein-compliance in orientation and bearing in landsense creation, the paper analyses the causes of the north-facing feature and the 'counter-tradition' room setting feature lie in the architectural pattern of HHR, revealing that people's psychological perceptions of orientation and bearing is distinct from the physical one. It points out these features of this building complex are the results of man's active adaptation to nature on the basis of respecting nature, which together manages to form a process of constructing the harmonious relationship between man and nature during land use. By the principle of the multiscale (trans-scale or cross-scale) spatiotemporal combination in landsense creation, the paper continues to analyze on the pattern of HHR and finds that it has both the function of cultural inheritance and the innovation of adaptation to new environment, which can promote the protection of historical and cultural elements during the course of development, and bring reference for the realization of sustainable development from the perspective of contemporary historical and cultural heritage protection. [ABSTRACT FROM AUTHOR]

The aim of the study was to investigate how maternal dietary patterns and maternal/fetal cytokines are associated with birth weight and whether cytokines mediate the association. A total of 469 pregnant women and their children were recruited for this prospective study. Dietary patterns in pregnancy were identified using factor analysis of data from three consecutive 24 h dietary recalls. Maternal and umbilical blood serum cytokines (adiponectin (APN), IL-6 and interferon- γ) were measured via ELISA. Path analysis was used to explore the relationships between maternal diet, cytokines and birth weight. Four dietary patterns were identified: a mainly fruit, dairy products and poultry diet (FDP); a mainly vegetables, beans and pork diet (VBP); a mainly fish, shrimp and soup diet (FS) and a mainly tuber and egg diet (TE). Path analysis showed the order of effects of dietary patterns on birth weight was FS>FDP>TE>VBP (β =0·130, 0·109, –0·094 and 0·046, respectively). Only the TE pattern's effect was negative. Maternal and fetal APN were positively associated with birth weight (β =0·045 and 0·226, respectively), and they mediated the association between the TE pattern and birth weight (indirect effect was 5·3 %). Maternal IL-6 was negatively associated with birth weight (β =–0·067) and mediated the association between maternal FDP and VBP patterns and birth weight (indirect effects were 10·1 and 100·0 %, respectively). All variables in the path explained 33·6 % of variation. These results suggested that maternal dietary patterns in pregnancy are associated with birth weight and mediated directly and indirectly through some maternal/fetal serum cytokines. [ABSTRACT FROM AUTHOR]

An octahedral metal–organic framework (MIL-101(Cr)) with a uniform size of ~550 nm was synthesized via hydrothermal reaction, and then was functionalized with sulfonic acid groups by concentrated sulfuric acid and trifluoromethanesulfonic anhydride. Mixed matrix membranes (MMMs) were fabricated by incorporating the as-prepared metal organic frameworks into sulfonated poly(ether ether ketone) (SPEEK). The gas separation performance of MMMs was investigated both in dry and humidified state. The addition of the sulfonated metal–organic framework increased the selectivity of the membranes for CO 2 /CH 4 and CO 2 /N 2 systems by increasing the CO 2 solubility, and the diffusion of gases through the porous metal organic frameworks led to the simultaneous increase in CO 2 permeability. The highest ideal selectivities for CO 2 /CH 4 and CO 2 /N 2 were 50 and 53 (at a CO 2 permeability of 2064 Barrer) in humidified state, respectively. The increased total water in MMMs led to increased CO 2 permeability and the increased bound water resulted in the improved CO 2 /gas selectivity. The effects of operating conditions on separation performance were investigated. [ABSTRACT FROM AUTHOR]

Polyethylenimine (PEI) was immobilized by MIL-101(Cr) (∼550 nm) via a facile vacuum-assisted method, and the obtained PEI@MIL-101(Cr) was then incorporated into sulfonated poly(ether ether ketone) (SPEEK) to fabricate mixed matrix membranes (MMMs). High loading and uniform dispersion of PEI in MIL-101(Cr) were achieved as demonstrated by ICP, FT-IR, XPS, and EDS-mapping. The PEI both in the pore channels and on the surface of MIL-101(Cr) improved the filler-polymer interface compatibility due to the electrostatic interaction and hydrogen bond between sulfonic acid group and PEI, and simultaneously rendered abundant amine carriers to facilitate the transport of CO2 through reversible reaction. MMMs were evaluated in terms of gas separation performance, thermal stability, and mechanical property. The as-prepared SPEEK/PEI@MIL-101(Cr) MMMs showed increased gas permeability and selectivity, and the highest ideal selectivities for CO2/CH4 and CO2/N2 were 71.8 and 80.0 (at a CO2 permeability of 2490 Barrer), respectively. Compared with the membranes doped with unfilled MIL-101(Cr), the ideal selectivities of CO2/CH4 and CO2/N2 for PEI@MIL-101(Cr)-doped membranes were increased by 128.1 and 102.4 %, respectively, at 40 wt % filler loading, surpassing the 2008 Robeson upper bound line. Moreover, the mechanical property and thermal stability of SPEEK/PEI@MIL-101(Cr) were enhanced.