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Nitrogen-doped flower-like porous carbon materials directed by in situ hydrolysed MgO： Promising support for Ru nanoparticles in catalytic hydrogenations

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Nano Research 2016年第10期9卷 3129-3140页

作者： mingming li MinghuiTang Jiang Deng Yong Wang Advanced Materials and Catalysis Group ZJU-NHU United R&D Center Department of Chemistry Zhejiang University Hangzhou310028 China

The development of novel simple, and convenient techniques for the fabrication of porous carbon materials with desirable properties, such as tunable pore structures and the presence of nitrogen functionalities, from renewable and abundant biomasses is required. We herein describe an in situ directing method for the preparation of a nitrogen-doped flower-like porous carbon （NFPC） employing arbitrarily shaped MgO from bio-derived glucosamine chloride （GAH）. Experimental evidence demonstrated that the structure directing effect of the Mg（OH）2 nanosheets formed in situ from MgO hydrolysis was key to this process, with the original MgO morphology being irrelevant. Furthermore, this method was applicable for a wide variety of biomass-derived carbon precursors. The resulting NFPC exhibited a high nitrogen content of 〈9 wt.%, and was employed as a support to anchor small Ru nanoparticles （average size = 2.7 nm）. The resulting Ru/NFPC was highly active in heterogeneous hydrogenations of toluene and benzoic acid, which demonstrated the advantages of nitrogen doping in terms of boosting catalytic performance.

关键词： nitrogen-doped porous carbon MgO in situ hydrolysis ruthenium aromatic hydrogenation

Highly ordered macroporous-mesoporous Ce0.4Zr0.6O2 as dual-functional material in a polysulfide polymer

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Nano Research 2018年第1期11卷 80-88页

作者： Zhenxing li Jianzheng Zhang mingming li Xiaofei xing Qiuyu Zhang State Key Laboratory of Heavy Oil Processing Institute of New Energy China University of Petroleum (Beijing) Beijing 102249 China Department of Applied Chemistry College of Science Northwestern Polytechnical University Xi'an 710072 China

A highly hierarchically ordered macroporous-mesoporous Ce0.4Zr0.602 solid solution with crystalline framework walls was directly and simply prepared using polystyrene （PS） microspheres and a block copolymer as dual templates. The PS microspheres and block copolymer were assembled into colloidal crystals and mesoscopic rod-like micelles as macroporous and mesoporous templates, respectively, by a one-step process. This process offers a facile method to prepare hierarchically ordered porous materials. Compared to commercial ceria, the macroporous-mesoporous Ce0.4Zr0.602 material significantly improved the ultraviolet resistance and mechanical performance of a polysulfide polymer. Because the ordered macroporous-mesoporous Ce0.4Zr0.602 can disperse uniformly in the polysulfide polymer based on the open macroporous structure for diffusion and mobility and mesoporous structure for high surface areas. Furthermore, these results show that better-performing polysulfide polymers can be achieved by adding hierarchically structured materials.

关键词： macroporous-mesoporous crystalline walls polysulfide polymer ultraviolet resistance mechanical performance

Evaluation of fiber optic methane sensor using a smoke chamber

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International Journal of Mining Science and Technology 2018年第6期28卷 969-974页

作者： mingming li Thomas Dubaniewicz Heather Dougherty Jim Addis National Institute for Occupational Safety and Health Pittsburgh Mining Research Division

This report presents the results of experiments to evaluate a prototype fiber optic methane monitor exposed to smoke using a smoke chamber to simulate atmospheric conditions in an underground coal mine after a fire or explosion. The experiments were conducted using test fires of different combustible sources commonly found in mines —douglas-fir wood, SBR belt, and Pittsburgh seam coal. The experiments were designed to assess the response of the fiber optic methane sensor to different contaminants,different contaminant levels and different contaminant durations produced from the test fires. Since the prototype methane monitor detects methane by measuring absorption at a specific wavelength, optical power at the absorption wavelength(1650 nm) was measured as a function of smoke concentration and duration. The other sensor response parameter-methane response times-were measured between smoke tests to assess the impact of soot accumulation on the sensor. Results indicate that the sensor screen effectively prevented smoke from obscuring the optical beam within the sensor head, with minimal impact on the system optical power budget. Methane response times increased with smoke exposure duration, attributed to soot loading on the protective screen.

关键词： Fiber optic Methane sensor Fires Optical power Response time

Key-Recovery Attacks on LED-like Block Ciphers

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Tsinghua Science and Technology 2019年第5期24卷 585-595页

作者： linhong Xu Jiansheng Guo Jingyi Cui mingming li the Information Science and Technology Institute

Asymmetric cryptographic schemes, represe nted by RSA, have bee n show n to be in secure un der quantum computing conditions. Correspondingly, there is a need to study whether the symmetric cryptosystem can still guarantee high security with the advent of quantum computers. In this paper, based on the basic principles of classical slide attacks and Simon's algorithm, we take LED-like lightweight block ciphers as research objects to present a security analysis under both classical and quantum attacks, fully considering the influence on the security of the ciphers of adding the round constants. By analyzing the information leakage of round constants, we can introduce the differential of the round constants to propose a classical slide attack on full-round LED-64 with a probability of 1. The analysis result shows that LED-64 is unable to resist this kind of classical slide attack, but that attack method is not applicable to LED-128. As for quantum attacks, by improving on existing quantum attack methods we dem on strate a qua ntum single-key slide attack on LED-64 and a quantum related-key attack on LED- 128, and indicators of the two attack algorithms are analyzed in detail. The attack results show that adding round consta nts does not completely improve the security of the ciphers, and quantum attacks can provide an exp on ential speed-up over the same attacks in the classical model. It further illustrates that the block cipher that is proved to be safe under classical settings is not necessarily secure under quantum conditions.

关键词： key-recovery attack cryptanalysis post-quantum cryptography lightweight block cipher LED

Bond behavior of the interface between concrete and basalt fiber reinforced polymer bar after freeze–thaw cycles

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Frontiers of Structural and Civil Engineering 2024年第4期18卷 630-641页

作者： li HONG mingming li Congming DU Shenjiang HUANG Binggen ZHAN Qijun YU Department of Structural Engineering Hefei University of TechnologyHefei 230009China Key Laboratory of Performance Evolution and Control for Engineering Structures Tongji UniversityShanghai 200092China Engineering Research Center of Low-carbon Technology and Equipment for Cement-based Materials(Ministry of Education) Hefei University of TechnologyHefei 230009China Hefei Cement Research&Design Institute Corporation Ltd. Hefei 230051China

The shear bond of interface between concrete and basalt fiber reinforced polymer(BFRP)bars during freeze–thaw(F–T)cycles is crucial for the application of BFRP bar-reinforced concrete structures in cold *** this study,48 groups of pull-out specimens were designed to test the shear bond of the BFRP-concrete interface subjected to F–T *** effects of concrete strength,diameter,and embedment length of BFRP rebar were investigated under numerous F–T *** results showed that a larger diameter or longer embedment length of BFRP rebar resulted in lower interfacial shear bond behavior,such as interfacial bond strength,initial stiffness,and energy absorption,after the interface goes through F–T ***,higher concrete strength and fewer F–T cycles were beneficial for enhancing the interfacial bond ***,a three-dimensional(3D)interfacial model based on the finite element method was developed,and the interfacial bond behavior of the specimens was analyzed ***,a degradation bond strength subjected to F–T cycles was predicted by a proposed mechanical *** predictions were fully consistent with the tested *** model demonstrated accuracy in describing the shear bond behavior of the interface under numerous F–T cycles.

关键词： F-T cycle interface shear bond strength bond stress−slip curves bond degradation

Aptamer-induced in-situ growth of acetylcholinesterase-Cu_(3)(PO_(4))_(2)hybrid nanoflowers for electrochemical detection of organophosphorus inhibitors

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Nano Research 2023年第10期16卷 12134-12143页

作者： limin Yang linjiao Qu Xiaolong Zhang mingming li Zhen liu State Key Laboratory of Heavy Oil Processing and Center for Bioengineering and Biotechnology China University of Petroleum(East China)Qingdao 266580China Institute of Biomedical Engineering Shenzhen Bay LaboratoryShenzhen 518055Chin

Enzyme-inorganic hybrid nanoflowers(HNFs)have shown excellent sensing capabilities due to their large specific surface area as well as the simplicity and mildness of the preparation ***,coupling HNFs to electrodes to fabricate a uniform and controllable enzymatic electrochemical sensing interface remains a ***,we proposed an aptamer-induced insitu fabrication strategy for preparing an HNF-based electrochemical sensor with ideal *** to this strategy is the introduction of acetylcholinesterase(AChE)-specific binding aptamer(Apt),which induces the in-situ growth of AChE-copper phosphate(Cu_(3)(PO_(4))_(2))HNFs on the surface of carbon paper(CP).In addition,a dense gold nanoparticle(AuNP)layer was electrodeposited on the CP for anchoring Apt and further extending the electroactive surface *** prepared AChECu_(3)(PO_(4))_(2)HNF/Apt/AuNP/CP biosensor exhibited a wide detection range from 1 to 107 pM for the four organophosphorus inhibitors,including isocarbophos,dichlorvos,methamidophos,and parathion,with detection limits down to 0.016,0.028,0.071,and 0.113 pM,*** the reactivation of pralidoxime chloride,the electrode can still recover 98.1%of the response after five times of repeated *** real sample detection,the biosensor achieved high recoveries from 96.45%to 100.13%.The detection target may be extendable to other AChE inhibitors(e.g.,drugs for Alzheimer’s disease).This study demonstrates for the first time the feasibility of using aptamers as an inducer to fabricate an electrochemical enzyme sensing interface *** strategy can be used to fabricate other enzyme-based biosensors and therefore has broader applications.

关键词： in-situ fabrication aptamer enzyme-inorganic hybrid nanoflowers electrochemical biosensor acetylcholinesterase inhibitors

Effects of proper drilling control to reduce respirable dust during roof bolting operations

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International Journal of Coal Science & Technology 2016年第4期3卷 370-378页

作者： mingming li Yi Luo Hua Jiang Department of Mining Engineering West VirginiaUniversity Morgantown WV 26505 USA

Dust generated from bolt hole drilling in roof bolting operation could have high quartz content. As a dust control measure, vacuum drilling is employed on most of the roof bolters in US underground mines. However, fine rock partic- ulates from drilling could escape from the dust collection system and become airborne under some circumstances causing the roof bolter operators expose to quartz-rich respirable dust. A previous research shows that drilling can be controlled through properly selected penetration and rotational rates to reduce the specific energy of drilling. Less specific energy means less energy is wasted on generating noise, heat and over-breakage of rock. It implies that proper control of drilling has a great potential to generate significantly less fine rock dust during drilling. The drilling experiments have been conducted to study the effect of controlling drilling on reducing respirable dust. The preliminary results show that the size distributions of respirable dust were different when controlling drilling in different bite depths. This paper presents the findings from laboratory experimental studies.

关键词： Drilling control Roof bolting Bite depth Respirable dust Size distribution

Modeling and analysis of cantilever beam with active-passive hybrid piezoelectric network

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Science China(Technological Sciences) 2013年第9期56卷 2326-2335页

作者： li mingming FANG Bo CAO DengQing HUANG WenHu School of Astronautics Harbin Institute of Technology

The active-passive hybrid piezoelectric network (APPN) is investigated to reduce the vibration of cantilever beam. Hamilton's principle with the Rayleigh-Ritz method is used to derive the equations of motion of the beam with the APPN. Only one piezoelectric actuator is bonded on the cantilever beam, so in the segment of the beam where the piezoelectric actuator is attached, the neutral axis is not the geometric center of the beam. This change on the neutral axis is considered in the process of deriving equations. Selecting RL circuit as passive shunt circuit, open-loop analysis is performed to gain insight into the passive damping features. Velocity feedback control is then employed to analyze the characteristics of the closed-loop system. Numerical results show that the APPN has a significant effect on vibration suppression, especially at narrow frequency bands. On this basis, variable RL circuit is proposed and analyzed for broadband vibration attenuation. Numerical simulations illustrate that this scheme is effective and feasible.

关键词： active-passive hybrid piezoelectric network active control passive shunt damping Hamilton's principle

A case study of continental shelf waves in the northwestern South China Sea induced by winter storms in 2021

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Acta Oceanologica Sinica 2024年第1期43卷 59-69页

作者： Junyi li Chen Zhou Min li Quanan Zheng mingming li lingling Xie Laboratory of Coastal Ocean Variation and Disaster Prediction College of Ocean and MeteorologyGuangdong Ocean UniversityZhanjiang 524088China Key Laboratory of Climate Resources and Environments in Continent Shelf Sea and Deep OceanDepartment of Education of Guangdong ProvinceZhanjiang 524088China Key Laboratory of Space Ocean Remote Sensing and Application Ministry of Natural ResourcesBeijing 100081China Department of Atmospheric and Oceanic Science University of MarylandCollege ParkMaryland 20742USA

This study aims to investigate characteristics of continental shelf wave(CSW)on the northwestern continental shelf of the South China Sea(SCS)induced by winter storms in *** and cruise observations,tidal gauge data at stations Hong Kong,Zhapo and Qinglan and sea surface wind data from January 1 to February 28,2021 are used to examine the relationship between along-shelf wind and sea level *** events of CSWs driven by the along-shelf sea surface wind are detected from wavelet spectra of tidal gauge *** signals are triply peaked at periods of 56 h,94 h and 180 h,propagating along the coast with phase speed ranging from 6.9 m/s to18.9 m/*** dispersion relation shows their property of the Kelvin mode of *** develop a simple method to estimate amplitude of sea surface fluctuation by along-shelf *** results are comparable with the observation data,suggesting it is *** mode 2 CSWs fits very well with the mooring current velocity *** results from rare current help to understand wave-current interaction in the northwestern SCS.

关键词： continental shelf waves Ekman transport Kelvin mode wavelet analysis northwestern South China Sea