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Modulating the Helicity of Sugar-Substituted Perylene Diimide Self-assemblies by Solvent Polarilities

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Chinese Journal of Chemistry 2015年第1期33卷 95-100页

作者： Qiang Guo junchao wang Lingyun Zhu Zhixiang Wei National Center for Nanoscience and Technology Beijing 10190China University of Chinese Academy of Sciences Beijing 100049China

Modulating the helicity of self-assemblies of conjugated molecules is important for their application in chiral *** this communication,solvent effect has been investigated on how to modulate the helicity of supramolecular assemblies of sugar-substituted perylenediimide(PTCDI-BAG)by using UV-Vis,circular dichroism spectroscopy and transmission electron ***-handed helical nanowires are obtained in the mixed solvent system of both N,N-dimethylformamide/ethanol(DMF/ethanol)and N,N-dimethylacetamide/ethanol(DMAC/ethanol).As changing the solvents into dimethyl sulfoxide/ethanol(DMSO/ethanol),ethylene glycol/ethanol(EG/ethanol),or N-methyl-2-pyrrolidone/ethanol(NMP/ethanol),only right-handed heical nanowires are *** chirality of supramolecular structures can be tuned by the controlling of the polarity of the solvents.A theoretical calculation is carried out to explain the chiral optical inversion phenomena of PTCDI-BAG aggregates in different solvents,which reveals that reversed CD spectra is due to the difference of clockwise and anticlockwise rotation of the dimer.

关键词： self-assembly solvent effect helicity conjugated molecules nanowire

Stego key searching for LSB steganography on JPEG decompressed image

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Science China(Information Sciences) 2016年第3期59卷 60-74页

作者： Jiufen LIU Yuguo TIAN Tao HAN junchao wang Xiangyang LUO Zhengzhou Information Science and Technology Institute State Key Laboratory of Mathematical Engineering and Advanced Computing

At present, steganalysis research focuses on detecting the existence of a hidden message. However,extracting the hidden information, i.e., an extracting attack, is crucial in obtaining effective evidence in computer forensics. Due to the difficulty of an extracting attack, research in this field is limited. In steganography with a stego key, an extracting attack is equivalent to recovering the stego key. In this paper we study a method for recovering the stego key in least significant bit(LSB) steganography with a decompressed JPEG image as the cover image. Firstly, the recovery of the stego key is translated into a cryptanalysis problem for a sequential cipher. The method for recovering the stego key is based on estimating the modification positions. The minimum size of the data used to recover the stego key successfully is discussed. Secondly, when a decompressed JPEG image is used as the cover image, the probability of recovering the cover pixels using recompression is *** is used to compute the error of the estimated sequence. Finally, an algorithm to recover the stego key in LSB steganography with a decompressed JPEG image as the cover image is proposed. The experimental results for the steganographic software, Hide and Seek 4.1 and its variant, which is a typical representative of LSB steganography, show that the proposed method can successfully recover the stego key in LSB replacement and LSB matching, i.e., the extracting attack is successful, and it outperforms three previous methods in terms of computational complexity.

关键词： steganalysis extracting attack LSB steganography decompressed JPEG image recompression stego key

Stabilizing MXene suspension with polyhydric alcohols

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Journal of Materials Science & Technology 2023年第34期165卷 219-224页

作者： Renfei Cheng junchao wang Tao Hu Yiming Zhao Yan Liang Xiaohui wang Yanchun Zhou Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Institute of Materials Science and Devices School of Materials Science and EngineeringSuzhou University of Science and TechnologySuzhou 215009China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China

MXenes have promises in myriad applications by virtue of two-dimensional nature and adjustable functional *** achieve the applications,MXenes are always first prepared in the form of aqueous ***,fast degradation caused by the attack of dissolved oxygen and water molecules is the main obstacle to the application of *** has come to light that the degradation preferentially takes place at defective sites and edges where defects *** tackle this problem and increase the stability,herein,using Ti_(3)C_(2)T_(x)MXene as a model material,we report a simple yet efficient strategy for long term storage of MXene suspension by introducing glycerol,a typical polyhydric *** effectiveness of the strategy is evidenced by structural compositional and morphological *** protects the defective sites of MXene flakes through restricting water and/or oxygen molecules from reactive *** is supported by ab initio molecular dynamics simulations that form hydrogen bonds between MXene and glycerol molecules just over defective *** this mechanism,other polyhydric alcohols,such as ethylene glycol and propylene glycol,are also effective in stabilizing Ti_(3)C_(2)T_(x)MXene *** strategy based on polyhydric alcohols has the potential to be extended to other MXenes,solving the most urgent challenge in the field of MXene engineering.

关键词： MXene Stability Polyhydric alcohols Glycerol Ethylene glycol and propylene glycol

Neuroprotective effects of cromakalim on cerebral ischemia-reperfusion injury in rats Correlation with hippocampal metabotropic glutamate receptor 1 alpha and glutamate transporter 1

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Neural Regeneration Research 2010年第9期5卷 678-682页

作者： Shilei wang junchao Liu Qingxian Chang Yu Li, Yan Jiang Shiduan wang Department of Anesthesiology Affiliated Hospital of Qingdao University Medical CollegeQingdao 266003Shandong ProvinceChina

BACKGROUND：Studies have reported that potassium channel openers exhibit a protective effect on cerebral ischemia-reperfusion injury and inhibit glutamate excitotoxicity in ***,the effects of the glutamate receptor 1α and glutamate transporter 1 remain poorly ***：To investigate the prophylactic use of the adenosine triphosphate-sensitive potassium channel opener cromakalim on neurological function and cerebral infarct size,as well as glutamate receptor 1α and glutamate transporter 1 expression,in rats with cerebral ischemia-reperfusion injury,and to explore action mechanisms underlying reduced glutamate excitotoxicity and neuroprotection in ***,TIME AND SETTING：Randomized,controlled,animal experiment was performed at the Brain Institute,Qingdao University Medical College,Between July 2008 and April ***：Cromakalim was purchased from Sigma,USA; rabbit anti-glutamate receptor 1α polyclonal antibody was offered by Wuhan Boster,China; rabbit anti-glutamate transporter 1 polyclonal antibody was offered by Santa Cruz Biotechnology,***：Sixty male,Wistar rats,aged 6 months,were randomly assigned to three groups （n =20）：sham-surgery,model,and *** thread methods were used to establish middle cerebral artery occlusion in rats from the model and cromakalim *** from the sham-surgery group were subjected to exposed common carotid artery,external carotid artery,and internal carotid artery,without *** （10 mg/kg） was administered 30 minutes prior to middle cerebral artery occlusion,but there was no intervention in the model and sham-surgery *** OUTCOME MEASURES：At 24 hours post-surgery,neurological behavioral functions were evaluated using Bederson＇s test,cerebral infarction volume was determined following tetrazolium chloride staining,and glutamate receptor 1a and glutamate transporter 1 expressions were detected using ***：Following cerebral ischemia-repe

关键词： cerebral ischemia-reperfusion cromakalim glutamate receptor 1α glutamate transporter 1

In-situ growth of large-area monolithic Fe_(2)O_(3)/TiO_(2) catalysts on flexible Ti mesh for CO oxidation

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Journal of Materials Science & Technology 2021年第10期69卷 119-128页

作者： Xinyue Tang junchao wang Jing Li Xinglai Zhang Peiqing La Xin jiang Baodan Liu Shenyang National Laboratory for Materials Science(SYNL) Institute o f Metal Research(IMR)Chinese Academy of Sciences(CAS)No.72 Wenhua RoadShenyang110016 China School of Materials Science and Engineering University of Science and Technology of ChinaNo.72 Wenhua Road.Shenyang110016 China State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of TechnologyLanzhou730050China

In this study, we reported the in-situ fabrication of a series of Fe_(2)O_(3)/TiO_(2) monolithic catalysts on flexible Ti mesh via plasma electrolytic oxidation process, hydrothermal reaction and chemical bath deposition(CBD) method. The morphology tailoring of Fe_(2)O_(3) nanostructures finds that Fe2O3 nanosheets supported on TiO2 exhibit superior catalytic performance with a complete oxidation of CO at 260℃. The catalytic stability test indicates that the in-situ grown Fe_(2)O_(3)/TiO_(2) catalysts own outstanding performance for continuous CO oxidation due to the strong substrate adhesion without mass loss. The microstructures and interfaces of Fe_(2)O_(3)/TiO_(2) catalysts are well studied using series of characterization techniques. The in-situ preparation strategy of metal oxide catalysts in this work will open up more opportunities for the rational design of variety of monolithic catalysts used for CO oxidation, de-NO_(x), three-way catalysis and other related application in industry.

关键词： Fe_(2)O_(3)/TiO_(2)nanostructures Monolithic catalysts Plasma electrolytic oxidation In-situ fabrication CO oxidation

Low-temperature and stable CO oxidation of Co_(3)O_(4)/TiO_(2) monolithic catalysts

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Chinese Chemical Letters 2021年第1期32卷 48-52页

作者： Xinyue Tang junchao wang Yonghui Ma Jing Li Xinglai Zhang Baodan Liu Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Foshan Graduate School of Northeastern University Foshan 528300China Structure Analysis Division Testing CenterInstitute of Metal ResearchChinese Academy of ScienceShenyang 110016China

Highly efficient Co_(3)O_(4)/TiO_(2) monolithic catalysts with enhanced stability were in-situ grown on Ti mesh for CO oxidation,which could completely oxidize CO at 120℃.The comprehensive catalytic performance is competitive to some noble metal catalysts and conventional Co_(3)O_(4) powder catalysts,which holds great potential toward industrial ***,the in-situ synthesis strategy of Co_(3)O_(4)/TiO_(2) monolithic catalysts on flexible mesh substrate in this work can be extended to the development of a variety of oxide-based monolithic catalysts towards diverse catalysis applications.

关键词： Co_(3)O_(4)/TiO_(2) In-situ growth Monolithic catalysts Long-term stability CO oxidation

Rockburst prediction using artificial intelligence techniques:A review

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Rock Mechanics Bulletin

Rock Mechanics Bulletin 2024年第3期3卷 1-13页

作者： Yu Zhang Kongyi Fang Manchao He Dongqiao Liu junchao wang Zhengjia Guo School of Electrical and Information Engineering Beijing University of Civil Engineering and ArchitectureBeijing100044China Beijing Key Laboratory of Intelligent Processing for Building Big Data Beijing University of Civil Engineering and ArchitectureBeijing100044China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyBeijing100083China Thomas Lord Department of Computer Science University of Southern CaliforniaLos Angeles90007CAUSA

Rockburst is a phenomenon where sudden,catastrophic failure of the rock mass occurs in underground deep regions or areas with high tectonic stress during the excavation *** disasters endanger the safety of people's lives and property,national energy security,and social interests,so it is very important to accurately predict *** rockburst prediction has not been able to find an effective prediction method,and the study of the rockburst mechanism is facing a *** the development of artificial intelligence(AI)techniques in recent years,more and more experts and scholars have begun to introduce AI techniques into the study of the rockburst *** previous research,several scholars have attempted to summarize the application of AI techniques in rockburst ***,these studies either are not specifically focused on reviews of the application of AI techniques in rockburst prediction,or they do not provide a comprehensive *** on the advantages of extensive interdisciplinary research and a deep understanding of AI techniques,this paper conducts a comprehensive review of rockburst prediction methods leveraging AI ***,pertinent definitions of rockburst and its associated hazards are ***,the applications of both traditional prediction methods and those rooted in AI techniques for rockburst prediction are summarized,with emphasis placed on the respective advantages and disadvantages of each ***,the strengths and weaknesses of prediction methods leveraging AI are summarized,alongside forecasting future research trends to address existing challenges,while simultaneously proposing directions for improvement to advance the field and meet emerging demands effectively.

关键词： Rockburst Rockburst prediction Artificial intelligence techniques

Polycaprolactone strengthening keratin/ bioactive glass composite scaffolds with double cross-linking networks for potential application in bone repair

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Journal of Leather Science and Engineering 2022年第1期4卷 1-13页

作者： Liying Sun Shan Li Kaifeng Yang junchao wang Zhengjun Li Nianhua Dan National Engineering Research Center of Clean Technology in Leather Indus-try Sichuan UniversityChengduChina Key Laboratory of Leather Chemistry and Engineering of Ministry of Education Sichuan UniversityChengduChina

In this study, we aimed at constructing polycaprolactone (PCL) reinforced keratin/bioactive glass composite scaffolds with a double cross-linking network structure for potential bone repair application. Thus, the PCL-keratin-BG com-posite scaffold was prepared by using keratin extracted from wool as main organic component and bioactive glass (BG) as main inorganic component, through both cross-linking systems, such as the thiol-ene click reaction between abundant sulfhydryl groups of keratin and the unsaturated double bond of 3-methacryloxy propyltrimethoxy silane (MPTS), and the amino-epoxy reaction between amino groups of keratin and the epoxy group in (3-glycidoxymethyl) methyldiethoxysilane (GPTMS) molecule, along with introduction of PCL as a reinforcing agent. The success of the thiol-ene reaction was verified by the FTIR and 1H-NMR analyses. And the structure of keratin-BG and PCL-keratin-BG composite scaffolds were studied and compared by the FTIR and XRD characterization, which indicated the successful preparation of the PCL-keratin-BG composite scaffold. In addition, the SEM observation, and contact angle and water absorption rate measurements demonstrated that the PCL-keratin-BG composite scaffold has interconnected porous structure, appropriate pore size and good hydrophilicity, which is helpful to cell adhesion, differentiation and prolifera-tion. Importantly, compression experiments showed that, when compared with the keratin-BG composite scaffold, the PCL-keratin-BG composite scaffold increased greatly from 0.91 ± 0.06 MPa and 7.25 ± 1.7 MPa to 1.58 ± 0.21 MPa and 14.14 ± 1.95 MPa, respectively, which suggesting the strong reinforcement of polycaprolactone. In addition, the biomineralization experiment and MTT assay indicated that the PCL-keratin-BG scaffold has good mineralization abil-ity and no-cytotoxicity, which can promote cell adhesion, proliferation and growth. Therefore, the results suggested that the PCL-keratin-BG composite scaffold has the

关键词： Keratin Bioactive glass Polycaprolactone Double cross-linking networks Bone regeneration

A chrome-free combination tanning strategy: based on silicic acid and plant tannin

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Journal of Leather Science and Engineering 2021年第1期3卷 166-178页

作者： Zetian Zhang Yang Liu junchao wang Taoling Xie Liying Sun Zhengjun Li National Engineering Research Center of Clean Technology in Leather Industry Sichuan UniversityChengdu 610065China Key Laboratory of Leather Chemistry and Engineering of Ministry of Education Sichuan UniversityChengdu 610065China

Silicic acid,commonly derived from cheap and easily available sodium silicate,has recently received great attention for application in leather industry to produce ecological leather with a cleaner ***,leather tanned with silicic acid alone is poor in storage stability,which limits its practical application in leather *** this work,a new environment-friendly combination tannage based on silicic acid and plant tannin was developed to address this issue along with improving the comprehensive performances of *** obtained leather was characterized by scanning electron microscopy,Fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy and so *** results showed that compared with leather tanned with silicic acid alone,the leather tanned with this combination method possessed improved thermal stability,enhanced mechanical properties,acceptable softness,appropriate hydrophilicity,and especially enhanced storage *** importantly,the combination tanned leather with 1:1 of the mass ratio of silicic acid to vegetable tannin(composed of valonea extract and mimosa extract with the same weight)had more prominent comprehensive *** addition,the results demonstrated that hydrogen bonding played an important role in the combination tanning ***,the hydrogen bonds generated between phenolic hydroxyl groups of polyphenols with silicon hydroxyl groups of silicic acid molecules inhibited the excessive condensation of Si-OH groups between ***,the assessment of environmental impact revealed the value of BOD 5/COD of the wastewater produced in this combination tanning process is more than 0.3,indicating the chrome-free combination tannage based on silicic acid and plant tannin was an environment-friendly tanning *** findings therefore indicated that a new chrome-free tanning method with silicon and biomass materials as main tanning agents has potential practical application

关键词： Silicic acid Plant tannin Chrome-free tannage Storage stability Environment-friendly