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Fan C.G.,Chongqing University | Fan C.G.,Hefei University of Technology | Li X.Y.,Basic Research Service | Mu Y.,Hefei University of Technology | And 3 more authors.
Applied Thermal Engineering | Year: 2017

Results from a series of simulations with regard to a mine laneway fire are presented. Large Eddy Simulation with Fire Dynamics Simulator was carried out for a fire located in a horizontal laneway, with investigating the smoke movement under the influence of stack effect formed inside an inclined laneway. The length and angle of the inclined laneway were systematically changed to show the influence of stack effect on the smoke characteristics, involving smoke temperature, smoke spread process and smoke backflow. Results show that as the stack effect is proportional to both length and angle of the inclined laneway, increasing either length or angle of the inclined laneway will contribute to decreasing the backflow length in the horizontal laneway and thus leading to more smoke flowing into the inclined laneway. A non-dimensional number Ri was proposed to demonstrate the coupled influence of length and angle of the inclined laneway on smoke movement, which can well distinguish whether there is a smoke backflow upstream of the fire or not. The critical value of Ri was found to be 100. For cases without backflow at the steady period of smoke movement, the time when the backflow disappears decreases with the increasing vertical height of the inclined laneway, and the data can be correlated well by an exponential expression. For all cases, the mass flow rate of smoke flowing into the inclined laneway increases with the increasing vertical height of the inclined laneway exponentially. © 2016 Elsevier Ltd


Zhang X.,Peking University | Wu Q.,Peking University | Ren J.,Peking University | Qian W.,Peking University | And 7 more authors.
Plant Physiology | Year: 2012

Jasmonates (JAs) regulate various stress responses and development processes in plants, and the JA pathway is tightly controlled. In this study, we report the functional characterization of two novel RING-type ubiquitin ligases, RING DOMAIN LIGASE3 (RGLG3) and RGLG4, in modulating JA signaling. Both RGLG3 and RGLG4 possessed ubiquitin ligase activities and were widely distributed in Arabidopsis (Arabidopsis thaliana) tissues. Altered expression of RGLG3 and RGLG4 affected methyl JA-inhibited root growth and JA-inductive gene expression, which could be suppressed by the coronatine insensitive1 (coi1) mutant. rglg3 rglg4 also attenuated the inhibitory effect of JA-isoleucine-mimicking coronatine on root elongation, and consistently, rglg3 rglg4 was resistant to the coronatine-secreting pathogen Pseudomonas syringae pv tomato DC3000, suggesting that RGLG3 and RGLG4 acted in response to the coronatine and promoted JA-mediated pathogen susceptibility. In addition, rglg3 rglg4 repressed wound-stunted plant growth, wound-stimulated expression of JA-responsive genes, and wound-induced JA biosynthesis, indicating their roles in JA-dependent wound response. Furthermore, both RGLG3 and RGLG4 responded to methyl JA, P. syringae pv tomato DC3000, and wounding in a COI1-dependent manner. Taken together, these results indicate that the ubiquitin ligases RGLG3 and RGLG4 are essential upstream modulators of JA signaling in response to various stimuli. © 2012 American Society of Plant Biologists. All Rights Reserved.


Chang S.,Shandong University | Yang X.,Basic Research Service | Sang Y.,Shandong University | Liu H.,Shandong University
Chemistry - An Asian Journal | Year: 2016

One of the most important applications for photocatalysis is engineered water treatment that photodegrades organic pollutants in wastewater at low cost. To overcome the low efficiency of batch degradation methods, continuous-flow photocatalytic reactors have been proposed and have become the most promising method for mass water treatment. However, most commercial semiconductor photocatalysts are granular nanoparticles with low activity and a narrow active light wavelength band; this creates difficulties for direct use in continuous-flow photocatalytic reactors. Therefore, a high-performance photodegradation photocatalyst with proper morphology or structure is key for continuous photocatalytic degradation. Moreover, a well-designed photocatalytic device is another important component for continuous-flow photocatalysis and determines the efficiency of photocatalysis in practical water treatment. This review describes the basic design principles and synthesis of photocatalysts with excellent performance and special morphologies suitable for a filtering photocatalysis process. Certain promising continuous photodegradation reactors are also categorized and summarized. Additionally, selected scientific and technical problems that must be urgently solved are suggested. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim


Gu Q.,University of Science and Technology Beijing | Wu G.,Basic Research Service | Lu X.,University of Science and Technology Beijing
Advanced Materials Research | Year: 2012

Coal process wastewater that discharged from coal conversion processes usually contains volatile phenol in high concentration. As a natural mineral, diatomite demonstrates its excellent adsorption performance especially in organic pollutants removal. Diatomite was used for phenol removal in cokingwastewater by adsorption and the effect of diatomite dosage, contact time, salinity, intitial pH conditon and reaction temperature were investigated. It was observed that the removal rate of phenol increased with an increase in the diatomite dosage and contact time. The solution salinity could inhibit the phenol adsorption onto diatomite slightly by cometitive adsorption. Alkaline conditions were especially favorable for phenol removal. The increased reaction temperature could improve phenol adsorption to a large extent as well. © (2012) Trans Tech Publications, Switzerland.


Sun X.,Beijing University of Chemical Technology | Gao N.,Beijing University of Chemical Technology | Li Q.,Beijing University of Chemical Technology | Zhang J.,CAS Changchun Institute of Applied Chemistry | And 3 more authors.
Langmuir | Year: 2016

The crystalline morphology and orientation of poly(3-hydroxybutyrate) (PHB) thin film on the poly(vinylphenol) (PVPh) sublayer with different thickness was studied by atomic force microscopy, X-ray diffraction, and infrared spectroscopy. PVPh sublayer influences the morphology of PHB greatly. Although edge-on lamellae form on both Si and PVPh surfaces at relatively lower crystallization temperature, the morphology of them is quite different. It appears as sheaflike edge-on lamellar morphology on PVPh sublayer. In addition, the edge-on lamellae prefer to form on the PVPh sublayers at much higher crystallization temperature compared with that on Si wafer. The PVPh layer thickness also influences the crystalline morphology of PHB. On a 30 nm thick PVPh layer, sheaflike edge-on lamellae form in a wide range of crystallization temperatures. When the PVPh thickness increases to 65 nm, fingerlike morphology is observed when the crystallization temperature is lower than 95 °C. The fingerlike morphology is caused by a diffusion-limited aggregation process, and it requires an optimum condition. Thickness ratio between PHB and PVPh sublayer and temperature are two key factors for the formation of fingerlike morphology. © 2016 American Chemical Society.


Wang S.,Beijing University of Posts and Telecommunications | Sun L.,Beijing University of Posts and Telecommunications | Sun Q.,Beijing University of Posts and Telecommunications | Li X.,Basic Research Service | Yang F.,Beijing University of Posts and Telecommunications
Mobile Information Systems | Year: 2015

With the rapid development of mobile wireless networks such as 4G and LET, ever more mobile services and applications are emerging in mobile networks. Faced with massive mobile services, a top priority of mobile information systems is how to find the best services and compose them into new value-added services (e.g., location-based services). Hence, service selection is one of the most fundamental operations in mobile information systems. Traditional implementation of service selection suffers from the problems of a huge number of services and reliability.We present an efficient approach to service selection based on computingQoS uncertainty that achieves the best solution in two senses: (1) the time cost for finding the best services is short and (2) the reliability of the selected services is high. We have implemented our approach in experiments with real-world and synthetic datasets. Our results show that our approach improves on the other approaches tested. © 2015 Shangguang Wang et al.


Ren L.,Shanxi Institute of Coal CAS Chemistry | Ren L.,University of Chinese Academy of Sciences | Yang J.,Shanxi Institute of Coal CAS Chemistry | Gao F.,Taiyuan University of Technology | Yan J.,Basic Research Service
Energy and Fuels | Year: 2013

The gasification reactivity of 13 carbonaceous materials in CO2 or in steam was studied in the temperature range 1000-1600 C. The gasification reaction was carried out in a drop-in-fixed-bed reactor under atmospheric pressure. The gasifying agent fed into the reactor either as pure gas or as 36% volumetric concentration in argon with a total gas flow rate of 500 mL/min. The test samples included different rank coals, petcokes, and graphites. The raw materials were used to eliminate the problem related to char prepreparation. The dynamic profiles of gasification rate were used to compare the gasification behaviors for different samples. The physicochemical characteristics of chars were evaluated by scanning electron microscopy and N2 adsorption method. The experimental results reveal that the difference in gasification reactivity among samples decreases as the temperature increases and is not distinguishable for most coals at 1600 C. However, the temperature is still critical for gasification of petcokes and some high-rank coals at high temperature. The gasification reactivity of petcokes is 2-9 times lower than that of coals at 1600 C. The kinetic analysis reveals that the temperature dependence of reactivity varies with the type of materials. It is interested to find that, in the temperature range 1400-1600 C, the gasification reactivity in CO2 is higher than that in steam for coals but not for petcokes. From the views of the reaction thermodynamics, the gas diffusion difficulty, and the catalytic effect, the high temperature is favorable to the CO 2-gasification. The effect of AAEMs (alkali and alkaline earth metals) should be a key factor. The content of AAEMs is apparent in coals but limited in petcokes. The Arrhenius plots reveal that the gasification mechanism may be altered around 1200 C for most of coals. The petcokes are appeared with the most compact physical structure and the least gasification reactivity. Either the shrinking core model (SCM) or the volume reaction model (VRM) is suitable for most of the samples and conditions but not suitable for the petcokes. A diffusion term associated with the carbon structure may be needed for modelling the gasification behaviors of the petcoke-like materials. © 2013 American Chemical Society.


Gu Q.,University of Science and Technology Beijing | Sun T.,University of Science and Technology Beijing | Wu G.,Basic Research Service | Li M.,University of Science and Technology Beijing | Qiu W.,Harbin Institute of Technology
Bioresource Technology | Year: 2014

This study aims to evaluate the effect of carrier filling ratio on the performance of a moving bed biofilm reactor in degrading chemical oxygen demand, phenol, thiocyanate, and ammonia from coking wastewater at 20. h of hydraulic retention time. The operational experiments under different carrier filling ratios ranging from 20% to 60% were investigated. The maximum removal efficiency of 89%, 99% and 99% for COD, phenol and thiocyanate, and minimum sensitivity to the increasing contaminants concentration in the influent were achieved at 50% carrier filling ratio. The Haldane competitive substrate inhibition kinetics model was used to describe the relationship between the oxygen uptake rate of ammonium oxidizers and the concentration of free ammonium. The highest biofilm microbial community functional diversity (Shannon's diversity index, H') and evenness (Shannon's evenness index, E') were obtained at 50% carrier filling ratio in all runs using a Biolog ECO microplate. © 2014 Elsevier Ltd.


Zhou S.,Shanxi Institute of Coal CAS Chemistry | Zhou S.,University of Chinese Academy of Sciences | Yang J.,Shanxi Institute of Coal CAS Chemistry | Liu Z.,Shanxi Institute of Coal CAS Chemistry | And 3 more authors.
Fuel Processing Technology | Year: 2011

The effect of temperature on reaction of H2S with carbon structures of a coke were studied in a fixed-bed quartz tube reactor coupled with two parallel detectors, flame photometric detector (FPD) and mass spectrum (MS). The uptake of H2S with the coke matrix was studied through a sulfur uptake/temperature programmed desorption process (SU/TPD) and a temperature programmed oxidation process (TPO). The results show that the sulfur imbibed by a demineralized coke at elevated temperatures is very stable, which can only be decomposed and released to gas phase under combustion conditions. The chemical imbibition of sulfur takes place at an elevated temperature. At relatively lower temperatures, H2S was adsorbed physically by the sample and then transformed to stable sulfur species. At higher temperatures, the chemical reactions between H2S and DM-Coke led to the formation of more stable sulfur-containing forms and consequently increased H2S uptake ability. This is essence of the temperature effect on the uptake of H2S by a de-mineralized coke. The irregular behavior with the temperature was caused by the different interactions. © 2009 Elsevier B.V.


PubMed | CAS Changchun Institute of Applied Chemistry, Basic Research Service and Beijing University of Chemical Technology
Type: Journal Article | Journal: Langmuir : the ACS journal of surfaces and colloids | Year: 2016

The crystalline morphology and orientation of poly(3-hydroxybutyrate) (PHB) thin film on the poly(vinylphenol) (PVPh) sublayer with different thickness was studied by atomic force microscopy, X-ray diffraction, and infrared spectroscopy. PVPh sublayer influences the morphology of PHB greatly. Although edge-on lamellae form on both Si and PVPh surfaces at relatively lower crystallization temperature, the morphology of them is quite different. It appears as sheaflike edge-on lamellar morphology on PVPh sublayer. In addition, the edge-on lamellae prefer to form on the PVPh sublayers at much higher crystallization temperature compared with that on Si wafer. The PVPh layer thickness also influences the crystalline morphology of PHB. On a 30 nm thick PVPh layer, sheaflike edge-on lamellae form in a wide range of crystallization temperatures. When the PVPh thickness increases to 65 nm, fingerlike morphology is observed when the crystallization temperature is lower than 95 C. The fingerlike morphology is caused by a diffusion-limited aggregation process, and it requires an optimum condition. Thickness ratio between PHB and PVPh sublayer and temperature are two key factors for the formation of fingerlike morphology.

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