Heavy metal stabilization in MSWI fly ash using an additive-assisted microwave hydrothermal method

Zhiwen Xu,Zhiyuan Liang,Huaishuang Shao,Qinxin Zhao 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.117 No.-

The dioxins and leachable heavy metals in municipal solid waste incineration (MSWI) fly ash made it ahazardous waste. Microwave hydrothermal with four common additives, Na2S, Na2SiO3, Na2B4O7 orH3BO3, was researched at different temperatures, L/S ratios, time and additive concentrations by singlefactor and orthogonal methods to achieve effective heavy metal stabilization and waste reuse of MSWIfly ash. The samples were investigated by XRD, BET, SEM, ICP-MS to determine the influence ofadditive-assisted microwave hydrothermal on heavy metals stabilizing. According to the results of theorthogonal study, the degree of influence of each parameter heavy metals stabilization was in the orderof additive, temperature, additive concentration, time and L/S ratio. Single-factor experiments suggestedthat the conditions of 125 C, 10 min, 3 mol/L Na2S and 2 mL/g were enough for the leaching concentrationof heavy metals meeting the specified limitation of China. The results of analyses confirmed thatmicrowave hydrothermal treatment with Na2S could enhance heavy metals stabilizing by forming zeolitesfor adsorption, precipitation and convert heavy metals to a more stable state. Microwave hydrothermalwith Na2S was a promising method to manage MSWI fly ash, which greatly decrease the reactiontime and realize wastes utilization.

Acoustic Waves Scattering from a Fluid-Saturated Porous Cylinder

Xu Jing,Liu Jinxia,Cui Zhiwen 한국물리학회 2020 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.77 No.7

This paper reports a study on plane waves in a fluid incident on an infinitely long fluid-saturated porous cylinder. With consideration of both the fluid dynamic viscosity and the inelastic loss of the frame of the porous media, as well as the application-wide frequency of the Biot-Stoll model, the theoretical calculation of acoustic scattering of an acoustic wave at oblique incidence is carried out. The acoustic backscattering spectrum is calculated and used to investigate the influence of the incident angle and the boundary conditions on the scattering characteristics. The results show that the position of the peak on the horizontal coordinate moves to higher frequency as the incident angle is increased. In the soft porous cylinder, whose shear wave velocity is lower than the velocity of the fluid, the change in the backscattering spectrum under the open-pore boundary condition is more obvious than that in the sealed-pore boundary condition. The influence of the incident angle is more obvious in a hard porous cylinder whose shear wave velocity is larger than the velocity of the fluid than it is in a soft porous cylinder.

Three-Dimensional Porous Carbon Nanotube Papers as Current Collector and Buffer for SnO2 Anodes

Xiaogang Sun,Zhiwen Qiu,Long Chen,Manyuan Cai,Jie Wang,Xu Li,Wei Chen,Zhenhong Liu,Hao Tang 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2017 NANO Vol.12 No.11

A novel three-dimensional porous conductive papers have been successfully synthesized via a simple physical route. Multi-walled carbon nanotubes (MWCNTs)@SnO2 composite anode materials are embedded in porous conductive papers. The peculiar structure can accommodate the huge volume expansion of MWCNTs@SnO2 composite anode materials during charge–discharge process. The framework formed by MWCNTs and cellulose can greatly improve the strength, stability and flexibility of the electrode. In addition, the structure successfully prevent the aggregation of SnO2 nanoparticles and collapse of MWCNTs@SnO2 composite electrode, leading to the improvement in electrochemical utilization and stable cyclability. The samples were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM), respectively. The electrochemical properties and application were evaluated by galvanostatic discharge–charge testing and cycling voltammetry. As a result, the MWCNTs@SnO2 composite electrode showed excellent rate performance. The discharge capacity remains about 680mAh g -1 after 100 cycles at 200mA g -1, and even around 300mAh g -1 at 1000mA g -1.

Optimal Strategies for Cooperative Spectrum Sensing in Multiple Cross-over Cognitive Radio Networks

( Hang Hu ),( Youyun Xu ),( Zhiwen Liu ),( Ning Li ),( Hang Zhang ) 한국인터넷정보학회 2012 KSII Transactions on Internet and Information Syst Vol.6 No.12

To improve the sensing performance, cooperation among secondary users can be utilized to collect space diversity. In this paper, we focus on the optimization of cooperative spectrum sensing in which multiple cognitive users efficiently cooperate to achieve superior detection accuracy with minimum sensing error probability in multiple cross-over cognitive radio networks. The analysis focuses on two fusion strategies: soft information fusion and hard information fusion. Under soft information fusion, the optimal threshold of the energy detector is derived in both noncooperative single-user and cooperative multiuser sensing scenarios. Under hard information fusion, the optimal randomized rule and the optimal decision threshold are derived according to the rule of minimum sensing error (MSE). MSE rule shows better performance on improving the final false alarm and detection probability simultaneously. By simulations, our proposed strategy optimizes the sensing performance for each cognitive user which is randomly distributed in the multiple cross-over cognitive radio networks.

Wavelet Noise Elimination & Its Application in Acoustic Leak Detection of Fast Reactor Steam Generator

Liu Zhanhui,Niu Xiaodong,Mu Guangyu,Shang Deyi,Xu Zhiwen,Guo Xiaoxin,Pang Yunjie 대한전자공학회 2005 ITC-CSCC :International Technical Conference on Ci Vol.2005 No.4

Effect of Glucagon-like Peptide 2 on Tight Junction in Jejunal Epithelium of Weaned Pigs though MAPK Signaling Pathway

Yu, Changsong,Jia, Gang,Jiang, Yi,Deng, Qiuhong,Chen, Zhengli,Xu, Zhiwen,Chen, Xiaolin,Wang, Kangning Asian Australasian Association of Animal Productio 2014 Animal Bioscience Vol.27 No.5

The glucagon-like peptide 2 (GLP-2) that is expressed in intestine epithelial cells of mammals, is important for intestinal barrier function and regulation of tight junction (TJ) proteins. However, there is little known about the intracellular mechanisms of GLP-2 in the regulation of TJ proteins in piglets' intestinal epithelial cells. The purpose of this study is to test the hypothesis that GLP-2 regulates the expressions of TJ proteins in the mitogen-activated protein kinase (MAPK) signaling pathway in piglets' intestinal epithelial cells. The jejunal tissues were cultured in a Dulbecco's modified Eagle's medium/high glucose medium containing supplemental 0 to 100 nmol/L GLP-2. At 72 h after the treatment with the appropriate concentrations of GLP-2, the mRNA and protein expressions of zonula occludens-1 (ZO-1), occludin and claudin-1 were increased (p<0.05). U0126, an MAPK kinase inhibitor, prevented the mRNA and protein expressions of ZO-1, occludin, claudin-1 increase induced by GLP-2 (p<0.05). In conclusion, these results indicated that GLP-2 could improve the expression of TJ proteins in weaned pigs' jejunal epithelium, and the underlying mechanism may due to the MAPK signaling pathway.

Apoptosis induced in vivo by new type gosling viral enteritis virus

Shun Chen,Anchun Cheng,Mingshu Wang,Dekang Zhu,Renyong Jia,Qihui Luo,Hengmin Cui,Yi Zhou,Yin Wang,Zhiwen Xu,Zhengli Chen,Xiaoyue Chen,Xiaoyu Wang 대한수의학회 2011 JOURNAL OF VETERINARY SCIENCE Vol.12 No.4

In this study, apoptosis was induced by new type gosling viral enteritis virus (NGVEV) in experimentally infected goslings is reported in detail for the first time. After 3-day-old goslings were orally inoculated with a NGVEV-CN strain suspension, the time course of NGVEV effects on apoptotic morphological changes of the internal tissues was evaluated. These changes were observed by histological analysis with light microscopy and ultrastructural analysis with transmission electron microscopy. DNA fragmentation was assessed with a terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay and DNA ladder analysis. A series of characteristic apoptotic morphological changes including chromatin condensation and margination, cytoplasmic shrinkage, plasma membrane blebbing, and formation of apoptotic bodies were noted. Apoptosis was readily observed in the lymphoid and gastrointestinal organs, and sporadically occurred in other organs after 3 days post-infection (PI). The presence and quantity of TUNEL-positive cells increased with infection time until 9 days PI. DNA extracted from the NGVEV-infected gosling cells displayed characteristic 180~200 bp ladders. Apoptotic cells were ubiquitously distributed, especially among lymphocytes, macrophages, monocytes, and epithelial and intestinal cells. Necrosis was subsequently detected during the late NGVEV-infection phase, which was characterized by cell swelling, plasma membrane collapse, and rapidly lysis. Our results suggested that apoptosis may play an important role in the pathogenesis of NGVE disease.