91 research outputs found
Effect of different carrier gases on productivity enhancement of a novel multi-effect vertical concentric tubular solar brackish water desalination device
A novel multi-effect vertical concentric tubular solar brackish water desalination device is introduced in present study. The device consists of four closely spaced concentric pipes, in which the feed water gets preheated by hot brine water to guarantee the evaporation efficiency. An experimental investigation and analytical analysis were carried out to signify the effect of carrier gas-water vapor mixture on productivity enhancement of the device. Different carrier gases were used in the performance evaluation: carbon dioxide, helium, nitrogen, oxygen, air and argon. The water yield and the top/bottom temperature values of condensation surface of the device with different carrier gases were tested. In addition, the present investigation is presented an approach to predict the theory yield based on the internal heat and mass transfer mechanism. The experimental results indicate that, when the heating temperature is 80âŻÂ°C and the carrier gas is helium, the water productivity rate can reach to 1.19âŻkg/h. It is increased by 30.76% than the carrier gas of air. The numerical results had been calculated and a consistent agreement with the experimental results had been obtained of different operation temperatures. The Dv under different heating temperature were obtained according to the experimental results
Performance of steel frames with new lightweight composite infill walls under curvature ground deformation
In this paper, the structural performance of steel frames with novel lightweight composite infill walls is experimentally and numerically investigated under curvature ground deformation, which is a common consequence of ground mining activities that can cause significant effects on structures and buildings in these areas. A new structural form that combines steel frames and lightweight composite infill walls has recently been used; its performance under curvature ground deformation is of great interest but still not entirely clear. This study compares the mechanical behavior of the open-frame, the closed-frame with mudsill, and the closed-frame with infill walls, through experimental testing under positive and negative curvature ground deformations. Structural responses such as basement counterforce, additional strains at different key locations, and effects of mudsill and infill walls are evaluated. In addition, 3D finite element models are established to simulate the performance of the tested samples and are validated by comparing the results against those from experiments. After validation, the numerical model is applied to a few complex structures incorporating the composite infill walls to investigate their structural performance under both positive and negative curvature ground deformation. It has been found that steel frames with the new composite infill walls can considerably increase the stiffness of structures in resisting ground deformation and re-distribute the loads amongst the beam and column members in the frame. Failure modes for the structures can also be changed by shifting the most dangerous ones from the upper part of the frame to the lower part. Moreover, it has been found that the vertical force of the infill walls is more sensitive to curvature ground deformation than the horizontal force. Further, the influence of the infill wall on the column is more significant, in comparison to that on the beam of the frame
Electrospun Conjugated Polymer/Fullerene Hybrid Fibers: Photoactive Blends, Conductivity through Tunnelling-AFM, Light-Scattering, and Perspective for Their Use in Bulk-Heterojunction Organic Solar Cells
Hybrid conjugated polymer/fullerene filaments based on MEH-PPV/PVP/PCBM are
prepared by electrospinning, and their properties assessed by scanning
electron, atomic and lateral force, tunnelling, and confocal microscopy, as
well as by attenuated total reflection Fourier transform-infrared spectroscopy,
photoluminescence quantum yield and spatially-resolved fluorescence.
Highlighted features include ribbon-shape of the realized fibers, and the
persistence of a network serving as a template for heterogeneous active layers
in solar cell devices. A set of favorable characteristics is evidenced in this
way in terms of homogeneous charge transport behavior and formation of
effective interfaces for diffusion and dissociation of photogenerated excitons.
The interaction of the organic filaments with light, exhibiting specific
light-scattering properties of the nanofibrous mat, might also contribute to
spreading incident radiation across the active layers, thus potentially
enhancing photovoltaic performance. This method might be applied to other
electron donor-electron acceptor material systems for the fabrication of solar
cell devices enhanced by nanofibrillar morphologies embedding conjugated
polymers and fullerene compounds.Comment: 35 pages, 9 figure
The mass transfer coefficient assessment and productivity enhancement of a vertical tubular solar brackish water still
This paper presents an experimental investigation of a single-effect vertical tubular solar brackish water desalination device, with an aim to determine the mass transfer coefficient and its enhancement. The device consists of two closely spaced concentric pipes. The outside of the inner pipe is covered with a wicking material and wetted with hot brackish water. The water vapor evaporated from the wicking material condenses on the inside of the outer pipe. The measured productivity and temperatures at various points are given for different wicking materials thickness, water flow rates and chamber pressure under the condition of given heating power. Mass transfer coefficients are calculated from the experimental results and then applied in the prediction of water productivity. The maximum discrepancy between the calculation yield and measurement yield is relatively small compared with previous study. In addition, it was found that the yield of the solar still is 23.9% higher when the chamber pressure is lower by 25 kPa due to the enhanced mass transfer. Similar, doubling the ambient air velocity can increase the water yield by about 17.0%
Study on effects of mudsill and infilled wallboard on response of steel frame under curvature surface deformation
The structural performance of steel frames with novel lightweight composite infilled wallboard is experimentally and numerically investigated under the curvature surface deformation. This study compares the mechanical behavior for the open-frame, the closed-frame with mudsill and the closed-frame with infilled wallboard, through experiment and finite element analysis, under the positive and negative curvature surface deformations respectively. The structural responses such as basement counterforce, additional strains at different key locations and the effects of mudsill and infilled wallboard are evaluated. It has been found that the steel frames with the new composite infilled wallboard can considerably increase the stiffness of the structures in resisting surface deformation and re-distribute the loads amongst the beam and column members in the frame. The force transmission effect of the mudsill accelerated the changes in the additional strain at column bottom. Frame beam is the main component that bears the curvature surface deformation. Mudsill has a consistent stress pattern with the frame beam and can significantly influence additional strain of the frame beam due to its stress sharing effect. The infilled wallboard is connected with the column-beam members and thereby influences the additional strain of the frame column significantly
Moral perfectionism and moral values, virtues, and judgments: A preliminary investigation
Moral perfectionism has a long tradition in philosophical inquiry, but so far has been ignored in psychological research. This article presents a first psychological investigation of moral perfectionism exploring its relationships with moral values, virtues, and judgments. In three studies, 539 university students responded to items of the Frost Multidimensional Perfectionism Scale (Frost, Marten, Lahart, & Rosenblate, 1990) adapted to measure personal moral standards (PMS) and concern over moral mistakes (CMM) and completed measures of moral values, virtues, and forgiveness, gratitude, and wrong behavior judgments. When partial correlations were computed controlling for the overlap between PMS and CMM, PMS showed positive correlations with moral values, virtues, reciprocal helping, forgiveness, and condemnation of wrong behaviors. In contrast, CMM showed a positive correlation only with indebtedness and a negative correlation with self-reliance. The present findings, while preliminary, suggest that moral perfectionism is a personality characteristic that may help explain individual differences in moral values, virtues, and judgments
Is personal growth initiative associated with later life satisfaction in Chinese college students? A 15âweek prospective analysis
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151959/1/ajsp12386.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151959/2/ajsp12386_am.pd
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