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Kinetics and capacities of non-reactive phosphorus (NRP) sorption to crushed autoclaved aerated concrete (CAAC)

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Journal of Environmental Sciences 2023年第5期127卷 799-810页

作者： Shuting Shen Xiang li Zhuofan Geng xiwu Lu School Energy and Environment Southeast UniversityNanjing 210096China ERC Taihu Lake Water Environment Wuxi Wuxi 214135China

With growing interest in resource recovery and/or reuse,wastematerials have been considered a promising alternative for phosphorus(P)adsorption because they are low-cost and easily accessible.Crushed autoclaved aerated concrete(CAAC),as representative construction waste,has been extensively studied for P removal in ecological technologies such as treatment wetlands.However,most of the previous studies focused on the adsorption of orthophosphate,namely reactive phosphorus,and lacked attention to non-reactive phosphorus(NRP)which is widely present in sewage.This study presents the first investigation on the potential and mechanism of CAAC removing four model NRP compounds.Adsorption isotherm and kinetics of NRP onto CAAC indicate that the removal of NRP was a chemisorption process and also involved a two-step pore diffusion process.The desorption experiment shows that different NRP species showed varying degrees of desorption.Most NRP was irreversibly adsorbed on CAAC.Among the model compounds considered in this study,the adsorption capacity and hydrolysis rate of organophosphorus were much less than that of inorganic phosphorus.Moreover,the adsorption of different NRP species by CAAC in the mesocosm study was different from the results of laboratory adsorption experiments,and the possible biodegradation was essential for the conversion and removal of NRP.The findings confirmed the validity of CAAC for NRP removal and the potential advantages of CAAC in terms of costs and environmental impact.This study will contribute to a better understanding of NRP conversion and environmental fate and that can be the basis for a refined risk assessment.

关键词： Non-reactive phosphorus Crushed autoclaved aerated concrete Phosphorus removal Sorption Wastewater treatment

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Near-microscopic grain boundary facilitates fatigue crack propagation in a polycrystalline Al–Zn–Mg–Cu alloy

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Progress in Natural Science:Materials International 2023年第1期33卷 120-125页

作者： Kai Wen Xiwu Li Baiqing Xiong Haitao lin Qinghong Wen Yanan li Hongwei Yan lizhen Yan Yongan Zhang Zhihui li Hongwei liu State Key Laboratory of Nonferrous Metals and Processes China GRINM Group Co. LTD. GRIMAT Engineering Institute Co. LTD. General Research Institute for Nonferrous Metals Southwest Aluminum(Group) Co. Ltd.

In present study, grain characteristics with sizes within 10–30 μm were fabricated from a same Al–Zn–Mg–Cu alloy, FCP behaviors of the alloys with small grain(SG alloy), medium grain(MG alloy) and large grain(LG alloy)were investigated and related fatigue fracture morphology was analyzed. With the enhancement of stress intensity factor range(ΔK), the alloy with larger grains possessed faster FCP rate, which were successively arranged as SG alloy > MG alloy > LG alloy at initial stage while turned to LG alloy > MG alloy > SG alloy at final stage for the stable expanding region. Except for conventional characteristics of striations, tearing ridges, secondary cracks,second phases, voids and dimples, more prominent grain boundary features appeared on fracture surface, especially for MG and LG alloy. The calculation of cyclic plastic zone(CPZ) sizes proved that grain boundary participated and promoted FCP behavior when CPZ covered grain and grain boundary together.

关键词： Fatigue crack propagation Grain size Grain boundary Cyclic plastic zone Al–Zn–Mg–Cu alloy

Sentiment analysis using deep learning approaches:an overview

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Science China(Information Sciences) 2020年第1期63卷 21-56页

作者： Olivier HABIMANA Yuhua li Ruixuan li xiwu GU Ge YU School of Computer Science and Technology Huazhong University of Science and Technology School of Computer Science and Engineering Northeastern University

Nowadays, with the increasing number of Web 2.0 tools, users generate huge amounts of data in an enormous and dynamic way. In this regard, the sentiment analysis appeared to be an important tool that allows the automation of getting insight from the user-generated data. Recently, deep learning approaches have been proposed for different sentiment analysis tasks and have achieved state-of-the-art results. Therefore, in order to help researchers to depict quickly the current progress as well as current issues to be addressed, in this paper, we review deep learning approaches that have been applied to various sentiment analysis tasks and their trends of development. This study also provides the performance analysis of different deep learning models on a particular dataset at the end of each sentiment analysis task. Toward the end, the review highlights current issues and hypothesized solutions to be taken into account in future work. Moreover, based on knowledge learned from previous studies, the future work subsection shows the suggestions that can be incorporated into new deep learning models to yield better performance. Suggestions include the use of bidirectional encoder representations from transformers(BERT), sentiment-specific word embedding models, cognition-based attention models, common sense knowledge, reinforcement learning, and generative adversarial networks.

关键词： sentiment analysis opinion mining deep learning neural network natural language processing(NLP) social network

Resistance and fitness costs in diamondback moths after selection using broflanilide, a novel meta-diamide insecticide

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Insect Science 2022年第1期29卷 188-198页

作者： Xi Sun Rui Wei linhong li Bin Zhu Pei liang xiwu Gao Department of Entomology China Agricultural UniversityBeijing100193China

The diamondback moth (DBM) Plutella xylostella (L.) (Lepidoptera: Plutellidae) is an insect pest found around the world that feeds on cruciferous crops. The DBM has become resistant to most insecticides in current use in the field. Broflanilide is a novel meta-diamide insecticide that binds to a new site on the γ-aminobutyric acid receptor and very efficiently protects against most pests in the order Lepidoptera, including DBM. In this study, the resistance of a laboratory-bred susceptible strain of DBM to broflanilide and the fitness costs posed by broflanilide to the DBM were evaluated. The DBM had no obvious resistance to broflanilide after 10 generations of selection. The realized heritability h2 was 0.033, suggesting a low risk of resistance developing in this strain. The F10 generation had no cross-resistance to the insecticides abamectin and endosulfan (which target the γ-aminobutyric acid receptor) and chlorantraniliprole (which targets a non-γ-aminobutyric acid receptor). The specific activities of important detoxification enzymes (cytochrome P450 monooxygenase, esterase, and glutathione S-transferase) were not obviously altered. However, the larval stage was prolonged and the adult stage was shortened significantly in F11 generation than the F0 generation. The total preoviposition period TPOP significantly prolonged 1.90 d in F11 generation. The fitness value Rf (0.93) was lower for the F11 generation than the F0 generation. The results indicated that long-term exposure to broflanilide exerts clear fitness costs in the DBM. This information will be useful in identifying reasonable broflanilide application guidelines for managing broflanilide resistance in the DBM.

关键词： broflanilide cross-resistance detoxifying enzymes fitness cost Plutella xylostella

Macro-micro dynamic behaviors and fracture modes of roll bonded 7A52/7A01/7B52 aluminum laminates in high velocity deformation

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Progress in Natural Science:Materials International 2018年第4期28卷 510-519页

作者： Guochuan Zhu Shuhui Huang Xiwu Li Zhihui li Youzhi Tong Yongan Zhang Baiqing Xiong State Key Laboratory of Nonferrous Metals and Processes General Research Institute for Nonferrous Metals Northeast light alloy limited liability Company Heilongjiang

Damage tolerance improvement in the lamination of aluminum alloy plates and composites has been reported in many studies. In the present study the macro-micro dynamic deformation behavior and related mechanisms of 7A52/7A01/7B52 laminated plates processed by hot roll bonding of 7A52, 7A01 and 7B52 plate at high strain rates and quasi-static compression has been investigated. The microstructure of the laminated plates was examined with backscatter diffraction(EBSD) techniques, scanning and transmission electron microscopies. The results showed that with increased strain rate, obvious strain rate hardening was observed in the single layer specimens. The peak flow stress of the multilayer samples was slightly higher than that of the 7A52 monolayer samples and much lower than that of the 7B52 monolayer samples at the same strain rate. Beyond the peak stress state, the strain hardening was replaced by thermal softening in the 7A52 layer, leading to low resistance of deformation and high tendency to facilitate deformation-induced adiabatic shear bands(ASBs) that consist of dynamic recrystallized grains. ASBs in laminated samples were deflected and bifurcated at the interface of 7A52 layer. In addition, bifurcated ASBs converged at the interface between the 7A52 and 7A01 layers. The high deformation resistance observed in the laminate under dynamic loading was a consequence of the high capacity for strain hardening in the 7A01 layer. This hardening effectively overcame the influences of thermal softening and dynamic recovery during dynamic loading. This study provides an understanding of the laminate’s microstructure evolution during dynamic deformation and its relevance to the fracture modes of a multilayer structure under dynamic loading.

关键词： Laminated plate Fracture mode Microstructure Aluminum alloy Mechanical properties

Dynamic response characteristic of 7N01/7A01/7050 aluminium multilayer plate at high strain rate

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Progress in Natural Science:Materials International 2021年第1期31卷 159-163页

作者： Guochuan Zhu Xiwu Li Baiqing Xiong Zhihui li Yongan Zhang lizhen Yan Kai Wen Hongwei Yan State Key Laboratory of Nonferrous Metals and Processes GRINM Group Co. LTD. GRIMAT Engineering Institute Co. LTD. General Research Institute for Nonferrous Metals State Key Laboratory for Performance and Structural Safety of Petroleum Tubular Goods and Equipment Materials CNPC Tubular Goods Research Institute

The correlations between the structures,fracture behavior and dynamic shear property were investigated for 7050 to 7 N01 layer of 7 N01/7 A01/7050 multilayer plate with different thickness ratio fabricated by hot rolling bonding.is The results showed that when thickness ratio of 7050 to 7 N01 layer was 1 and 7050 layer was backplane,the absorbed energy of the multilayer plate was 39% higher than that of 7050 alloy.The excellent energy absorbing ability of 7 N01/7 A01/7050 multilayer plate is attributed to the blunted cracks in 7 A01 interlayer,the enhanced 7050 layer by decreasing of secondary cracks and the delaying dynamic failure of 7050 layer.

关键词： Multilayer structure Structural Adiabatic shear band Fracture

Aging behavior and fatigue crack propagation of high Zn-containing Al-Zn-Mg-Cu alloys with zinc variation

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Progress in Natural Science:Materials International 2017年第2期27卷 217-227页

作者： Kai Wen Yunqiang Fan Guojun Wang Longbing Jin Xiwu Li Zhihui li Yongan Zhang Baiqing Xiong State Key Laboratory of Non-ferrous Metals and Processes General Research Institute for Nonferrous Metals Northeast light Alloy Co. Ltd.

In the present work, the influence of two-step aging treatments on hardness, electrical conductivity and mechanical properties of two high Zn-containing Al-Zn-Mg-Cu alloys with zinc content variation was investigated and the detailed T76 aging parameters were proposed. The microstructure of the precipitates were studied by transmission electron microscopy(TEM) and high-resolution transmission electron microscopy(HREM) and then quantitatively investigated with the aid of an image analysis. The fatigue performances were researched by the fatigue crack propagation(FCP) rate test and fracture morphology was observed with scanning electron microscopy(SEM). The results show that the matrix precipitate size distributions of both alloys had significant difference, so as to fatigue crack propagation rates and fracture appearance. The shear and bypass mechanisms of dislocation-precipitate interactions were employed to explain the difference. Among the shearable precipitates, the proportion of larger size precipitates for the higher zinc content alloy is bigger than that for the lower zinc content alloy. The coarse shearable precipitates hinder the propagation of the fatigue cracks, leading to inferior FCP rate. For both alloys, the shear mechanism possesses the dominant factor, finally causing a preponderance in the FCP resistance for the higher zinc content alloy than the lower one.

关键词： Al-Zn-Mg-Cu alloy Fatigue crack propagation Precipitate Aging treatment

A Novel Hybrid Method to Analyze Security Vulnerabilities in Android Applications

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Tsinghua Science and Technology 2020年第5期25卷 589-603页

作者： Junwei Tang Ruixuan li Kaipeng Wang xiwu Gu Zhiyong Xu School of Computer Science and Technology Huazhong University of Science and TechnologyWuhan 430074China Math and Computer Science Department Suffolk UniversityBostonMA 02101USA and also with Shenzhen Institute of Advanced TechnologyChinese Academy of ScienceShenzhen 518055China

We propose a novel hybrid method to analyze the security vulnerabilities in Android applications.Our method combines static analysis,which consists of metadata and data flow analyses with dynamic analysis,which includes dynamic executable scripts and application program interface hooks.Our hybrid method can effectively analyze nine major categories of important security vulnerabilities in Android applications.We design dynamic executable scripts that record and perform manual operations to customize the execution path of the target application.Our dynamic executable scripts can replace most manual operations,simplify the analysis process,and further verify the corresponding security vulnerabilities.We successfully statically analyze 5547 malwares in Drebin and 10 151real-world applications.The average analysis time of each application in Drebin is 4.52 s,whereas it reaches 92.02 s for real-word applications.Our system can detect all the labeled vulnerabilities among 56 labeled applications.Further dynamic verification shows that our static analysis accuracy approximates 95%for real-world applications.Experiments show that our dynamic analysis can effectively detect the vulnerability named input unverified,which is difficult to be detected by other methods.In addition,our dynamic analysis can be extended to detect more types of vulnerabilities.

关键词： Android security vulnerability analysis static analysis dynamic analysis

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Role of biologic components in a novel floating-bed combining Ipomoea aquatic, Corbicula fluminea and biofilm carrier media

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Frontiers of Environmental Science & Engineering 2014年第2期8卷 215-225页

作者： Hailiang SONG Xianning li Wei li xiwu LU School of Energy and Environment Southeast University Nanjing 210096 China Engineering Research Center for Water Environmental Protection of Taihu Lake Southeast University Wuxi Branch Wuxi 214135 China

A novel floating-bed incorporated with water spinach （Ipomoea aquatica）, Asiatic clam （Corbicula fluminea）, and carrier media supported biofilm was developed for eutrophic water purification. The contribu- tions of each biologic component to the removals of total nitrogen （TN）, total phosphorus （TP） and Chl.a were examined. The nutrient removals due to the direct uptake by either water spinach or Asiatic clam were less than 10%, suggesting a negligible role of biologic assimilation and leaving the biofilm as the indispensable biologic compo- nent in the floating-bed. Chl.a was reduced mainly by Asiatic clams via filter-feeding. Meanwhile, the digestion and excretion of Asiatic clams benefited the proliferation of nitrifying and denitrifying bacteria, resulting in the improvement of TN removal. In summary, the synergetic effects of water spinach, Asiatic clams and biofilms would promote the eutrophic water treatment performance of floating-bed in comparison with the conventional floating- bed with vegetation as the single biologic component.

关键词： floating-bed Corbicula fluminea biofilm cartier eutrophication