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Investigation of basic properties of fly ash from urban waste incinerators in China

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Journal of Environmental Sciences 2007年第4期19卷 458-463页

作者： jiang jian-guo XU Xin wang Jun YANG Shi-jian ZHANG Yan Department of Environmental Science and Engineering Tsinghua University Beifing 100084 China. Shanghai Environment and Science Academy Shanghai 201203 China

Basic properties of fly ash samples from different urban waste combustion facilities in China were analyzed using as X-ray fluorescence （XRF）, scanning electron microscopy （SEM）, X-ray diffraction （XRD）. The leaching toxicity procedure and some factors influencing heavy metals distribution in fly ash were further investigated. Experimental results indicate that the fly ash structures are complex and its properties are variable. The results of XRF and SEM revealed that the major elements （〉10000 mg/kg, listed in decreasing order of abundance） in fly ash are O, Ca, Cl, Si, S, K, Na, Al, Fe and Zn. These elements account for 93% to 97%, and the content of Cl ranges from 6.93% to 29.18 %, while that of SiO2 does from 4.48% to 24.84%. The minor elements （1000 to 10000 mg/kg） include Cr, Cu and Pb. Primary heavy metals in fly ash include Zn, Pb, Cr, Cu etc. According to standard leaching test, heavy metal leaching levels vary from 0 to 163.10 mg/L （Pb） and from 0.049 to 164.90 mg/L （Zn）, mostly exceeding the Chinese Identification Standard for hazardous wastes. Morphology of fly ash is irregular, with both amorphous structures and polycrystalline aggregates. Further research showed that heavy metals were volatilized at a high furnace temperature, condensed when cooling down during the post-furnace system and captured at air pollution control systems. Generally, heavy metals are mainly present in the forms of aerosol particulates or tiny particulates enriched on surfaces of fly ash particles. The properties of fly ash are greatly influenced by the treatment capacities of incinerators or the variation of waste retention time in chamber. Fly ash from combustors of larger capacities generally has higher contents of volatile component and higher leaching toxicity, while those of smaller capacities often produce fly ash containing higher levels of nonvolatile components and has lower toxicity. The content of heavy metals and leaching toxicity maybe have no convincing correlatio

关键词： urban waste incinerator fly ash heavy metals leaching toxicity

Computational fluid dynamics simulation and experimental analysis of ultrafine powder suspension

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Rare Metals 2020年第7期39卷 850-860页

作者： wang-Chao Wu jian Cui Hao jiang Hai-Bo jiang Chun-Zhong Li School of Materials Science and Engineering East China University of Science and TechnologyShanghai 200237China

The suspension characteristics of ultrafine powder slurry in the stirred vessel were simulated by using computational fluid *** results show that the Rushton disk turbine impeller is more conducive to maintaining suspended homogeneity and circulation of slurry compared with the pitch blade turbine pumping up impeller and the pitch blade turbine pumping down *** the increase in stirring speed enhances turbulent fluctuation and anisotropic velocity of the fluid at the cost of more power consumption,which improves dispersibility and suspensibility of the ***,the change of impeller clearance has a weak influence on the flow pattern,and the impeller clearance of 0.32T(T is the diameter of the bottom of the reactor)can achieve better dispersivity and suspensibility of the particles with lower power consumption and larger axial *** experiments of surface coating modification of ultrafine titanium dioxide(TiO2)were carried out under the same conditions for those of the simulation *** surface film morphology and photocatalytic properties of the modified TiO2 were analyzed,and the obtained data are well consistent with the simulation results.

关键词： Computational fluid dynamics simulation Ultrafine powder slurry Suspension quality Impeller type Stirring speed Impeller clearance

Relativistic Borromean states

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Chinese Physics C 2021年第4期45卷 41-46页

作者： Ziyue wang Shao-jian jiang Yin jiang Physics Department Tsinghua UniversityBejjing 100084China State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Innovation Academy for Precision Measurement Science and TechnologyChinese Academy of SciencesWuhan 430071China Physics Department Beihang UniversityBeijing 100191China

In this work,the existence of Borromean states is discussed for bosonic and fermionic cases in both therelativistic and non-relativistic limits from the 3-momentum shell *** the linear bosonic model,we check the existence of Efimov-like states in the bosonic *** both limits a geometric series of singularities is found in the 3-boson interaction vertex,while the energy ratio is reduced by around 70%in the relativistic limit because of the anti-particle *** by the quark-diquark model in heavy baryon studies,we have carefully examined the p-wave quark-diquark interaction and found an isolated Borromean pole at finite energy *** may indicate a special baryonic state of light quarks in high energy quark *** other cases,trivialresults are obtained as *** the relativistic limit,for both bosonic and fermionic cases,potential Borromean states are independent of the mass,which means the results would also be valid even in the zero-mass limit.

关键词： few-body systems Efimov state relativistic systems

Experimental investigation on cenosphere-aluminum syntactic foam-filled tubes under axial impact loading

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第11期24卷 978-990页

作者： Li wang Boyi ZHANG jian ZHANG Yuexin jiang Wei wang Gaohui WU School of Civil Engineering Harbin Institute of TechnologyHarbin 150090China Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education Harbin Institute of TechnologyHarbin 150090China Center for Metal Matrix Composites Engineering Technology Harbin Institute of TechnologyHarbin 150006China

A new syntactic foam material was prepared by screening three different average particle sizes of cenospheres(150,200,and 300μm)from industrial waste fly *** impact testing on syntactic foam filler and foam-filled tubes was conducted using a drop hammer test *** effects of parameters,such as the size of cenospheres and the impact velocity,on the mechanism of deformation,mechanical characteristics,and capacity for energy absorption of the specimen were *** this basis,the differences in compressive properties exhibited by the syntactic foam-filled tubes under the two loading conditions were *** results indicate that with the decrease in the average diameter of cenospheres,the initial peak crushing load and mean crushing load of foam-filled tubes increase,while the compression efficiency *** specific energy absorption(SEA)of the syntactic foam-filled tube can reach 25 J/*** the increase of impact velocity,the SEA of the specimen increases *** was demonstrated that the syntactic foam-filled tube exhibits a higher effective energy absorption ratio under impact loading compared to quasi-static loading.

关键词： Cenosphere-aluminum syntactic foam Crashworthiness Mechanical properties Absorption of energy

Relaxed Stability Criteria for Time-Delay Systems:A Novel Quadratic Function Convex Approximation Approach

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 996-1006页

作者： Shenquan wang Wenchengyu Ji Yulian jiang Yanzheng Zhu jian Sun College of Electrical and Electronic Engineering Changchun University of TechnologyChangchun 130012China the College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266590China Key Laboratory of Complex Systems Intelligent Control and Decision Beijing Institute of TechnologyBeijing 100081China

This paper develops a quadratic function convex approximation approach to deal with the negative definite problem of the quadratic function induced by stability analysis of linear systems with time-varying *** introducing two adjustable parameters and two free variables,a novel convex function greater than or equal to the quadratic function is constructed,regardless of the sign of the coefficient in the quadratic *** developed lemma can also be degenerated into the existing quadratic function negative-determination(QFND)lemma and relaxed QFND lemma respectively,by setting two adjustable parameters and two free variables as some particular ***,for a linear system with time-varying delays,a relaxed stability criterion is established via our developed lemma,together with the quivalent reciprocal combination technique and the Bessel-Legendre *** a result,the conservatism can be reduced via the proposed approach in the context of constructing Lyapunov-Krasovskii functionals for the stability analysis of linear time-varying delay ***,the superiority of our results is illustrated through three numerical examples.

关键词： Equivalent reciprocal combination technique quadratic function convex approximation approach stability timevarying delay

Achievement of giant cryogenic refrigerant capacity in quinary rare-earths based high-entropy amorphous alloy

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Journal of Materials Science & Technology 2022年第7期102卷 66-71页

作者： Yikun Zhang jian Zhu Shuo Li jiang wang Zhongming Ren State Key Laboratory of Advanced Special Steels&Shanghai Key Laboratory of Advanced Ferrometallurgy&School of Materials Science and Engineering Shanghai UniversityShanghai 200444China

Magnetic refrigeration(MR)by utilizing the magnetocaloric(MC)effect is recognized as one of the most potential promising solid state environmentally friendly and high efficiency alternative method to the well-used state-of-the-art gas compression cooling *** this work,a systematic investigation of quinary equi-atomic rare-earths(RE)based Er_(20) Ho_(20) Gd_(20) Ni_(20) Co_(20) high-entropy(HE)amorphous alloy in terms of the microstructure,magnetic and magnetocaloric(MC)properties have been *** Er_(20) Ho_(20) Gd_(20) Ni_(20) Co_(20) exhibits promising glass forming ability with an undercooled liquid region of 72 *** cryogenic MC performances can be found in wide temperature from∼25 and∼75 K,close to H_(2) and N_(2) liquefaction,*** from the largest magnetic entropy change(-S M)reaches 17.84 J/(kg K)with 0-7 T magnetic field change,corresponding refrigerant capacity(RC)attains a giant value of 1030 J/*** promising cryogenic MC performances together with the unique HE amorphous characterizations make the quinary Er_(20) Ho_(20) Gd_(20) Ni_(20) Co_(20) HE amorphous alloy attractive for cryogenic MR applications.

关键词： HE-amorphous ribbons Magnetocaloric performances Rare earths Magnetic properties Giant refrigerant capacity

Influence of the heat irrigating effect of radiofrequency ablation on regional liver tissue in Bama miniature pigs

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World Journal of Gastrointestinal Oncology 2021年第2期13卷 109-118页

作者： jian Feng Song wang Kai jiang Department of Hepatobiliary Surgery Chinese PLA General HospitalBeijing 100853China Department of General Surgery Taizhou Central Hospital(Taizhou University Hospital)Taizhou 318000Zhejiang ProvinceChina

BACKGROUND The results of the heat irrigating effect of radiofrequency ablation(RFA)are uncertain,and the accurate impact of the heat irrigating effect on regional liver tissue is unknown due to a lack of control *** The aim of this study was to determine the influence of the heat irrigating effect of RFA on regional liver tissue in Bama miniature *** Eight Bama miniature pigs were randomly divided into the observation group(group A)and the control group(group B),with 4 pigs/*** RFA electrode needle was implanted near the hepatic segment vasculature(3-5 mm from the hepatic segment portal vein)under ultrasound guidance in group ***,an RFA electrode needle was implanted far from the hepatic segment vasculature(8-10 mm from the hepatic segment portal vein)in group *** left internal lobe and right medial lobe were chosen as RFA sites in each *** was performed at the left internal lobe on day one in each pig,and at the right medial lobe 7 d *** RFA lasted 12 *** general status of the pigs and serious complications were observed during the perioperative *** pigs were sacrificed and the livers were removed immediately after RFA on the eighth *** samples were roughly ***-eosin and Ki67 staining,as well as TUNEL detection,were performed on the tissue *** All 8 animals successfully underwent ultrasound-guided *** serious complications,such as massive hemorrhage,biliary fistula,severe pleural effusion,pneumothorax,peripheral organ failure,or renal failure occurred in any of the animals during the perioperative *** RFA coagulative necrosis lesion was spherical and the surrounding liver tissue showed an inflammatory *** difference in the Suzuki score of the liver tissue surrounding the ablated portal vein,and its distal area between groups A and B,was statistically significant(P<0.05).More apoptotic cells were seen in liver tissue surrounding the ablated portal vein and

关键词： Radiofrequency ablation Heat irrigating effect Animal experimental Cell apoptosis Immunohistochemistry Thermal damage

Characteristics of change in water quality along reclaimed water intake area of the Chaobai River in Beijing, China

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Journal of Environmental Sciences 2016年第12期28卷 93-102页

作者： Lei Yang jiangtao He Yumei Liu jian wang Lie jiang Guangcai wang Beijing Key Laboratory of Water Resources and Environmental Engineering China University of Geosciences Beijing 100083 China Beijing Xinguohuan Environmental Technology Development Co. Ltd. Beijing 100044 China East China University of Technology Nanchang 330013 China jiangxi Institute of Geo-Environment Monitoring Nanchang 330012 China

To reveal the basic characteristics and controlling factors of water quality change in the project Wenyu to Chaobai reclaimed water diversion, the water quality in the study area was monitored for one year at seven monitoring sites. Inverse geochemical models of the statistical groups were developed using PHREEQC to elucidate the hydrochemistry characteristics of reclaimed water and the factors. The monitoring results indicated that nitrogen and phosphorus contents were significantly reduced along the river mainly caused by seasonal and location variation. The pH ranged from 7.44 to 9.81. Photosynthesis of algae and denitrification in anaerobic microenvironment ultimately led to a sudden pH increase after the jian River and the Chaobai River confluence. Mg2＋ and SO^- levels dropped obviously in the summer and increased in winter seasons after intersection. Na＋ and C1- are relatively stable, and marked drop in the concentration only after the two rivers meet. And there is a decrease of Ca2＋ and HCO~ and increase in CO^- during monitoring period. As a whole, the primary ions and nutrient components, including nitrogen and phosphorus, had high levels in winter. Algae＇s photosynthesis and respiration were observed to have an impact on the river water quality; there was precipitation-dissolution of minerals and denitrification from upstream to downstream. Inverse geochemical PHREEQC modeling confirmed that there was precipitation of aragonite or calcite, and gypsum or anhydrite in summer, and dissolution in winter; as well as precipitation of dolomite in winter, and cationic exchange and denitrification along the river.

关键词： Reclaimed water Chaobai River Water quality PHREEQC

Influence of Adding Ti Powder in Preform on Microstructure and Mechanical Properties of Al_2O_3p/Steel Composites by Squeeze Casting

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Journal of Wuhan University of Technology(Materials Science) 2018年第1期33卷 164-170页

作者：卢德宏 wang jian YU Jing jiang Yehua Faculty of Materials Science and Engineering Kunming University of Science and Technology

To improve the mechanical properties of alumina particulates reinforced steel matrix composite, Ti powder was added into the alumina preform, a 5140 steel matrix composite was fabricated by squeeze casting, and the influences of Ti powder on the microstructure, hardness and bending strength of the composite were investigated, compared with the composite without adding Ti powder. Applied Ti powder and alumina particulates were 10-25 μm and 100-180 μm in size, respectively. Both composites were successfully fabricated, however Ti powder addition increased the infiltration thickness of the composite. In the Ti contained composite, a TiC film in micron scale is formed on the surface of alumina particles, many TiC aggregates are dispersed in the steel matrix without obvious remaining Ti powder. The hardness and the three-point bending strength of the composite reach 49.5 HRC and 1 018 MPa, respectively, which are 17.9% and 52.4% higher than those of the composite in the absence of Ti addition. Fracture morphology shows that the debonding of alumina particulates is eliminated for the composite in the presence of Ti addition. Sessile drop test shows the average wetting angle between 5140 steel and that of Ti coated Al2O3 is about 82.15°, much lower than the wetting angle 150° between steel and pure Al2O3. Therefore, the increase in the mechanical properties of the composite is attributed to the improvement of Al2O3 p/steel interface wetting and bonding by adding Ti powder in the preform.

关键词： squeeze casting Al2O3 steel matrix composites interface mechanical properties