49 research outputs found
Roommate relationships in Chinese university dormitories: students' life experience and perception
The residential arrangement in which 4 to 6 students share one room during each year of their undergraduate studies presents a particular context in Chinese universities. How students manage these spaces and their relationships with each other are important to these young people’s everyday lives, their friendships and tensions in higher education. However, this is not widely researched in higher education studies. The few existing Chinese studies on this type of relationship tend to focus on dorm conflicts, attributing these to students’ lack of collectivistic and harmonious oriented awareness and social abilities. However, students’ everyday interactions and relationship negotiations and their associations with the materialities of dorms and wider institutional and sociocultural contexts are often overlooked. Thus, I conducted a qualitative study to explore these questions, bringing together literature drawing on the debates of student’s social relationships in higher education, relationality in personal life and materiality in domestic settings (particularly shared living) to examine the lived experiences of students living in Chinese dormitories. Alongside analysing 10 Chinese universities’ digital platforms about their policies of student dormitories and roommates, I also interviewed 30 undergraduate and postgraduate Chinese university students, who also produced their dorm photographs of their dorms and emotion maps, depicting their living experiences in the shared dormitories. As revealed by the data, student dormitories are conceived and presented as rule-bound training sites for being ‘good’ citizens, students are expected to acquire competences like ‘collective spirit’ and a sense of group responsibility. Nevertheless, the thesis demonstrates that students’ acquisition and practices of these competencies and their micro intimacies and conflicts in shared dorm living are more complex, multifaceted and unpredictable than assumed in existing literatures and, the ways they are shaped by universities’ institutional environments as well as, the design and materials of the shared residential spaces are also multifaceted and unpredictable. The project thus broadens understanding of university roommate relationships in Chinese studies. It also builds dialogues among the sociological debates about higher education, relationality and materiality, extending these literatures by bringing them to bear on new global contexts
BASIC:A Comprehensive Model for so <sub>x</sub>Formation Mechanism and Optimization in Municipal Solid Waste (MSW) Combustion
[Image: see text] Municipal solid waste (MSW) incineration is one of the main techniques currently used for waste to energy (WTE) conversion in China. Although the sulfur content in MSW is lower than that in coal, its emission cannot be neglected due to environmental pollution, malodor, health problems, and global climate change. Therefore, it is particularly important to effectively predict and control the sulfur pollutants. In this study, a comprehensive model was developed and coupled with the full combustion process bed model bulk accumulated solids incineration code (BASIC) to investigate the formation and transformation processes of sulfur in MSW incineration. The submodels of the four stages in the MSW combustion processes; governing equations of mass, momentum, and energy conservation; and various chemical reactions were included in the model. Based on this model, the effects of different parameters on the formation of sulfur pollutants during the incineration process were studied under different operating conditions. The study finds that for SO(X) formation, initial temperature, primary air volume, and material particle size have significant impacts, whereas pressure shows a less significant effect. This article also considers H(2)S, COS, and CS(2) formation under different conditions. An optimization study was performed to reduce SO(X) pollutants
Upgrading of fast pyrolysis liquid fuel from biomass over Ru/gamma-Al2O3 catalyst
Biomass is one of the important renewable energy. More attention has been paid on conversion of biomass and the upgrading of its products. In this paper, the bio-oil was prepared by pyrolysis of pine sawdust in fast pyrolysis installation. A series of ruthenium catalysts were prepared for the upgrading of bio-oil. The catalytic activity was evaluated by the reaction of the model compound (acetic acid) under 3 MPa hydrogen pressure. The effects of Ru-loading and second metal addition on the catalytic activity were investigated. The 0.5Ru/gamma-Al2O3 catalyst with 0.5%Co addition exhibited the highest activity, giving the highest conversion of acetic acid (30.98%). After upgrading over this catalyst, the properties of the pyrolysis bio-oil were improved. The content of the esters increased by 2-fold in the upgraded oil than in the raw one. The GC-MS spectrometry analysis showed that not only the hydrogenation but also the esterification happened in the bio-oil over the CoRu/gamma-Al2O3 catalyst. Results indicate that it is possible to improve the properties of bio-oil by hydrotreating and esterifying carboxyl groups. (C) 2011 Elsevier Ltd. All rights reserved.</p
A High-Throughput, High-Accuracy System-Level Simulation Framework for System on Chips
Today's System-on-Chips (SoCs) design is extremely challenging because it involves complicated design tradeoffs and heterogeneous design expertise. To explore the large solution space, system architects have to rely on system-level simulators to identify an optimized SoC architecture. In this paper, we propose a system-level simulation framework, System Performance Simulation Implementation Mechanism, or SPSIM. Based on SystemC TLM2.0, the framework consists of an executable SoC model, a simulation tool chain, and a modeling methodology. Compared with the large body of existing research in this area, this work is aimed at delivering a high simulation throughput and, at the same time, guaranteeing a high accuracy on real industrial applications. Integrating the leading TLM techniques, our simulator can attain a simulation speed that is not slower than that of the hardware execution by a factor of 35 on a set of real-world applications. SPSIM incorporates effective timing models, which can achieve a high accuracy after hardware-based calibration. Experimental results on a set of mobile applications proved that the difference between the simulated and measured results of timing performance is within 10%, which in the past can only be attained by cycle-accurate models
Removal of Pharmaceutical and Personal Care Products (PPCPs) from Municipal Waste Water with Integrated Membrane Systems, MBR-RO/NF
This study focuses on the application of combining membrane bioreactor (MBR) treatment with reverse osmosis (RO) or nanofiltration (NF) membrane treatment for removal of pharmaceuticals and personal care products (PPCPs) in municipal wastewater. Twenty-seven PPCPs were measured in real influent with lowest average concentration being trimethoprim (7.12 ng/L) and the highest being caffeine (18.4 ng/L). The results suggest that the MBR system effectively removes the PPCPs with an efficiency of between 41.08% and 95.41%, and that the integrated membrane systems, MBR-RO/NF, can achieve even higher removal rates of above 95% for most of them. The results also suggest that, due to the differences in removal mechanisms of NF/RO membrane, differences of removal rates exist. In this study, the combination of MBR-NF resulted in the removal of 13 compounds to below detection limits and MBR-RO achieved even better results with removal of 20 compounds to below detection limits
Catalytic Oxidation of Chlorobenzene over Ruthenium-Ceria Bimetallic Catalysts
A series of Ru-based mono and bimetallic materials were prepared and evaluated in the catalytic oxidation of chlorobenzene. Among the different Ru-based catalysts, 1Ru/TiO2(P25) was the most active catalyst and contributed the lowest complete oxidation temperature, suggesting that commercial P25 TiO2 was the best support for Ru catalysts. After ceria oxides were introduced into the Ru catalytic system, the catalytic activity of 1Ru-5Ce/TiO2(Rutile) dramatically improved and that of P25 supported catalysts was decreased. Comparing the chlorobenzene consumption rates for 1Ru/TiO2 and 1Ru-5Ce/TiO2 at 280 degrees C, it could be concluded that monometallic Ru catalytic system was appropriate for P25 support, and the Ru-Ce bimetallic catalytic system was suitable for the rutile TiO2 support. At 280 degrees C, for 1Ru-5Ce/TiO2(Rutile) and 1Ru-5Ce/TiO2(P25), the chlorobenzene conversion was stabilized at approximately 91% and 86%, respectively. According to the physicochemical properties of the catalysts as characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), and Hydrogen temperature programmed reduction (H-2-TPR), it can be concluded that (a) electrophilic O-ads species play an important role in VOCs oxidation; (b) abundant RuO2 nanoparticles on the surface of 1Ru-5Ce/TiO2(Rutile) result in higher catalytic activity and stability; and (c) dispersion is not the major factor for the catalytic activity, rather the unique structure greatly facilitated the catalytic activity and stability.</p
Removal of Pharmaceutical and Personal Care Products (PPCPs) from Municipal Waste Water with Integrated Membrane Systems, MBR-RO/NF
山梨醇水相催化重整制取芳香化合物
研究了山梨醇水相催化重整对制备芳烃类化合物的调控规律.研究表明,芳烃类、酮类、呋喃类及有机酸类化合物为油相的主要成分.当3%的镍负载在复合分子筛时,芳烃碳收率达到了34.36%:而当金属负载量达到20%时,碳收率仅为4.82%.同时,不同的反应参数对碳收率也有较大的影响.碳收率随着温度的升高逐渐增大:但随着液时空速与氢气压力的增加而减小.因此,合适的温度、较长的滞留时间及较低的氢气压力有利于芳烃的生成
Investigation of Low Latitude Spread-F Triggered by Nighttime Medium-Scale Traveling Ionospheric Disturbance
In the current study, we investigated the mechanism of medium-scale traveling ionospheric disturbance (MSTID) triggering spread-F in the low latitude ionosphere using ionosonde observation and Global Navigation Satellite System-Total Electron Content (GNSS-TEC) measurement. We use a series of morphological processing techniques applied to ionograms to retrieve the O-wave traces automatically. The maximum entropy method (MEM) was also utilized to obtain the propagation parameters of MSTID. Although it is widely acknowledged that MSTID is normally accompanied by polarization electric fields which can trigger Rayleigh–Taylor (RT) instability and consequently excite spread-F, our statistical analysis of 13 months of MSTID and spread-F occurrence showed that there is an inverse seasonal occurrence rate between MSTID and spread-F. Thus, we assert that only MSTID with certain properties can trigger spread-F occurrence. We also note that the MSTID at night has a high possibility to trigger spread-F. We assume that this tendency is consistent with the fact that the polarization electric field caused by MSTID is generally the main source of post-midnight F-layer instability. Moreover, after thorough investigation over the azimuth, phase speed, main frequency, and wave number over the South America region, we found that the spread-F has a tendency to be triggered by nighttime MSTID, which is generally characterized by larger ΔTEC amplitudes
Investigation of Low Latitude Spread-F Triggered by Nighttime Medium-Scale Traveling Ionospheric Disturbance
In the current study, we investigated the mechanism of medium-scale traveling ionospheric disturbance (MSTID) triggering spread-F in the low latitude ionosphere using ionosonde observation and Global Navigation Satellite System-Total Electron Content (GNSS-TEC) measurement. We use a series of morphological processing techniques applied to ionograms to retrieve the O-wave traces automatically. The maximum entropy method (MEM) was also utilized to obtain the propagation parameters of MSTID. Although it is widely acknowledged that MSTID is normally accompanied by polarization electric fields which can trigger Rayleigh–Taylor (RT) instability and consequently excite spread-F, our statistical analysis of 13 months of MSTID and spread-F occurrence showed that there is an inverse seasonal occurrence rate between MSTID and spread-F. Thus, we assert that only MSTID with certain properties can trigger spread-F occurrence. We also note that the MSTID at night has a high possibility to trigger spread-F. We assume that this tendency is consistent with the fact that the polarization electric field caused by MSTID is generally the main source of post-midnight F-layer instability. Moreover, after thorough investigation over the azimuth, phase speed, main frequency, and wave number over the South America region, we found that the spread-F has a tendency to be triggered by nighttime MSTID, which is generally characterized by larger ΔTEC amplitudes