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Synthesis and adsorption performance of lead ion-imprinted micro-beads with combination of two functional monomers

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Journal of Environmental Sciences 2011年第12期23卷 1955-1961页

作者： Linyan Zhu Zhiliang Zhu ronghua Zhang Jun Hong Yanling Qiu State Key Laboratory of Pollution Control and Resource Reuse Tongji University Shanghai 200092 China Department of Chemistry Tongji University Shanghai 200092 China Key Laboratory of Yangtze River Water Environment Ministry of Education of China Shanghai 200092 China

A novel ion-imprinted polymer, lead ion-imprinted micro-beads with combination of two functional monomers, was synthesized using the W/O/W polymerization method. Two functional monomers, 1,12-dodecanediol-O,O’-diphenyl-phosphonic acid （DDDPA） and 4-vinylpyridine, were used to form a suitable construction with micro-pores fitting the template and recognition sites. The eflects of adsorbent dosage, solution pH and the competitive ions on the adsorption and separation eflciency of lead ions were investigated. The lead ion-imprinted micro-beads were eflcient for lead ions removal from aqueous solution in a broad pH range （4–9）, when the adsorbent dosage was above 0.1 g/L. The adsorption process obeyed the pseudo second-order kinetics model and it only took half an hour to reach the equilibrium. The adsorption isotherm of lead ion was described by the Langmuir model （R2 0.99） with a maximum adsorption capacity of 116.9 mg/g. In the presence of competitive ions Co2＋ and Cd2＋, the lead ion-imprinted micro-beads showed a high selectivity for lead ions. The selectivity coeficient of Pb2＋/Cd2＋ and Pb2＋/Co2＋are 99.3 and 114.7, respectively.

关键词： lead ions adsorption lead ion-imprinted micro-beads selective separation recognition

Numerical simulation of dust distribution at a fully mechanized face under the isolation effect of an air curtain

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Mining Science and Technology 2011年第1期21卷 65-69页

作者： Wang Pengfei Feng Tao Liu ronghua School of Resources and Safety Engineering Central South University Changsha 410083 China School of Energy ＆Safety Engineering Hunan University of Science and Technology Xiangtan 411201 China

At a fully mechanized working face of a coal mine as prototype,we investigated,by simulation,the flow field and dust distribution during the process of its isolation by a curtain of air,using the CFD software, *** results show that the air curtain installed on the shearer can effectively prevent the dust （especially the respirable dust）from diffusing into the work area of the operator,reducing the dust concentration on the side of the operator and greatly improving his working *** field application of the air curtain shows that the dust-isolation effect of an air curtain is quite *** isolation efficiency for respiratory dust is over 70%and,as well,it has good dust-isolation effect for nonrespiratory *** air curtain is a useful way to resolve the problem of dust-isolation at a fully mechanized working *** has a practical background elsewhere with more extensive applications.

关键词： Fully mechanized face Air curtain Dust distribution Numerical simulation Dust-isolation efficiency

Immobilization of Lead and Cadmium in Contaminated Soil Using Amendments: A Review

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Pedosphere 2015年第4期25卷 555-568页

作者： Amanullah MAHAR WANG Ping LI ronghua ZHANG Zengqiang College of Natural Resources and Environment Northwest A&F University Centre for Environmental Sciences University of Sindh

Since the inception of industrial revolution, metal refining plants using pyrometallurgical processes have generated the prodigious emissions of lead(Pb) and cadmium(Cd). As the core target of such pollutants, a large number of soils are nowadays contaminated over widespread areas, posing a great threat to public health worldwide. Unlike organic pollutants, Pb and Cd do not undergo chemical or microbial breakdown and stay likely in site for longer duration after their release. Immobilization is an in-situ remediation technique that uses cost-effective soil amendments to reduce Pb and Cd availability in the contaminated soils. The Pb and Cd contamination in the soil environment is reviewed with focus on source enrichment, speciation and associated health risks, and immobilization options using various soil amendments. Commonly applied and emerging cost-effective soil amendments for Pb and Cd immobilization include phosphate compounds, liming, animal manure, biosolids, metal oxides, and biochar. These immobilizing agents could reduce the transfer of metal pollutants or residues to food web(plant uptake and leaching to subsurface water) and their long-term sustainability in heavy metal fixation needs further assessment.

关键词： bioavailability biochar biosolids heavy metal public health remediation soil extraction

Unstructured Road Extraction in UAV Images based on Lightweight Model

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 372-384页

作者： Di Zhang Qichao An Xiaoxue Feng ronghua Liu Jun Han Feng Pan School of Automation Beijing Institute of TechnologyBeijing 100081China Tianjin Institute of Maritime Navigation Instruments Tianjin 300130China The 716th Research Institute of China Shipbuilding Group Co. LtdJiangsu 222061China

There is no unified planning standard for unstructured roads,and the morphological structures of these roads are complex and *** is important to maintain a balance between accuracy and speed for unstructured road extraction *** road extraction algorithms based on deep learning have problems such as high model complexity,high computational cost,and the inability to adapt to current edge computing ***,it is best to use lightweight network *** the need for lightweight models and the characteristics of unstructured roads with different pattern shapes,such as blocks and strips,a TMB(Triple Multi-Block)feature extraction module is proposed,and the overall structure of the TMBNet network is *** TMB module was compared with SS-nbt,Non-bottleneck-1D,and other modules via *** feasibility and effectiveness of the TMB module design were proven through experiments and *** comparison experiment,using multiple convolution kernel categories,proved that the TMB module can improve the segmentation accuracy of the *** comparison with different semantic segmentation networks demonstrates that the TMBNet network has advantages in terms of unstructured road extraction.

关键词： Unstructured road Lightweight model Triple Multi-Block(TMB) Semantic segmentation net

Experimental study on atomization characteristics and dust-reduction performance of four common types of pressure nozzles in underground coal mines

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International Journal of Coal Science & Technology 2020年第3期7卷 581-596页

作者： Han Han Pengfei Wang ronghua Liu Chang Tian Work Safety Key Lab on Prevention and Control of Gas and Roof Disasters for Southern Coal Mines Hunan University of Science and TechnologyXiangtan411201China School of Resource Environment and Safety Engineering Hunan University of Science and TechnologyXiangtan411201China Department of Civil and Architectural Engineering and Mechanic University of ArizonaTucsonAZ85721USA

Pressure nozzle is commonly used in the dust-reduction techniques by spraying of underground coal *** on the internal structure,the pressure nozzle can be divided into the following types:spiral channel nozzle,tangential flow-guided nozzle and X-swirl *** order to provide better guidance on the selection of nozzles for the coal mine dust-reduction systems by spraying,we designed comparing experiments to study the atomization characteristics and dust-reduction performance of four commonly used nozzles in the coal mine underground with different internal *** the experimental results on the atomization characteristics,both the tangential flow-guided nozzle and the X-swirl nozzle have high flow *** atomization angle is the largest in the spiral non-porous nozzle,and smallest in both the X-swirl nozzle and the spiral porous *** spraying range and the droplet velocity are inversely proportional to the atomization *** the water pressure is low,the atomization performance of the spiral non-porous nozzle is the best among the four types of *** atomization performance of the X-swirl nozzle is superior to other types when the water pressure is *** the high water pressure,the particle size of the atomized droplets is smallest in the X-swirl *** the experiments on the dust-reduction performance of the four types of nozzles and the comprehensive analysis,the X-swirl nozzle is recommended for the coal mine application site with low water pressure in the dust-reduction system,while at the sites with high water pressure,the spiral non-porous nozzle is recommended,which has the lowest water consumption and obvious economic advantages.

关键词： Pressure nozzle Atomization characteristics Dust-reduction performance Droplets Dust

Silicone Chain Extender for Recycled Polyethylene-terephthalate with Higher Flexibility

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Journal of Wuhan University of Technology(Materials Science) 2019年第5期34卷 1228-1232页

作者： WANG Li HUANG ronghua North China University of Water Resources and Electric Power Zhengzhou 450046China School of Power&Mechanical Engineering Wuhan UniversityWuhan 430072China School of Materials Science&Engineering Hubei UniversityWuhan 430062China Engineering Center of New Tobacco Product China Tobacco Hubei Industrial Co LtdWuhan 430040China

To decrease the modulus and increase the mechanical properties of recycled PET by introducing the flexible segments, the recycled polyethylene-terephthalate(PET) was modified by the chain extender produced with 2, 4, 6, 8-tetramethyl-2, 4, 6, 8-tetra(2, 3-epoxypropoxy) propylcyclotetrasiloxane by the hydrosilylation reaction. Different percentages of chain extender were used in order to investigate the effect of chain extender content on the modulus of PET. The dynamic mechanical analysis was performed on PET samples, which showed that Tg of PET was firstly raised by the addition of chain extender and then decreased. Small amplitude shearing test performed on PET samples confirmed that the addition of the flexible segments could remarkably decrease the modulus of PET, which would be helpful for the extrusion process. The entanglements from branches were also influenced by the addition of extender.

关键词： PET chain extender silicone flexibility branches

Recent advances in enzyme-free and enzyme-mediated single-nucleotide variation assay in vitro

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National Science Review 2024年第5期11卷 365-384页

作者： Erhu Xiong Pengfei Liu Ruijie Deng Kaixiang Zhang ronghua Yang Jinghong Li Key Laboratory of Chemical Biology &Traditional Chinese Medicine Research Ministry of EducationCollege of Chemistry and Chemical Engineering Hunan Normal University College of Biomass Science and Engineering Healthy Food Evaluation Research CenterSichuan University School of Pharmaceutical Sciences Key Laboratory of Targeting Therapy and Diagnosis for Critical Diseases Zhengzhou University Department of Chemistry Center for Bioanalytical Chemistry Key Laboratory of Bioorganic Phosphorus Chemistry& Chemical BiologyTsinghua University Beijing Institute of Life Science and Technology

Single-nucleotide variants(SNVs) are the most common type variation of sequence alterations at a specific location in the genome, thus involving significant clinical and biological information. The assay of SNVs has engaged great awareness, because many genome-wide association studies demonstrated that SNVs are highly associated with serious human diseases. Moreover, the investigation of SNV expression levels in single cells are capable of visualizing genetic information and revealing the complexity and heterogeneity of single-nucleotide mutation-related diseases. Thus, developing SNV assay approaches in vitro, particularly in single cells, is becoming increasingly in demand. In this review, we summarized recent progress in the enzyme-free and enzyme-mediated strategies enabling SNV assay transition from sensing interface to the test tube and single cells, which will potentially delve deeper into the knowledge of SNV functions and disease associations, as well as discovering new pathways to diagnose and treat diseases based on individual genetic profiles. The leap of SNV assay achievements will motivate observation and measurement genetic variations in single cells, even within living organisms, delve into the knowledge of SNV functions and disease associations, as well as open up entirely new avenues in the diagnosis and treatment of diseases based on individual genetic profiles.

关键词： single-nucleotide variant point mutation in vitro enzyme-free assay enzyme-mediated assay

A Preliminary Research on Middle School Students'Academic Subjective Well-Being and Its Major Influential Factors

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Frontiers of Education in China 2006年第2期1卷 316-327页

作者： Liu Dianzhi Zhang ronghua School of Education Soochow UniversitySuzhou 215021China School of Foreign Languages Soochow UniversitySuzhou 215021China

This study is conducted with self-developed questionnaire on 910 middle school students,aimed at describing middle school students'academic subjective well-being and exploring its influential *** show that(1)Academic subjective well-being of middle school students is generally low and there exist differences in different schools and *** from non-key middle schools have lower academic subjective well-being than those from the key *** 2 students in both junior and senior middle schools have the lowest academic subjective well-being.(2)Factors directly affecting middle school students'academic subjective well-being are academic experience and the present academic achievements,with the former playing a major role.(3)Factors indirectly influencing middle school students'academic subjective well-being are social pressure and expected academic achievements,both of which influence students'academic subjective well-being through students'academic experience or their present academic achievements.

关键词： Academic subjective well-being(Academic SWB) Middle school students Academic experience School achievement Social pressure

Mineral Surface after Reaction with Aqueous Solution at High Temperatures and Pressures

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Acta Geologica Sinica(English Edition) 2000年第2期74卷 406-411页

作者： ZHANG Xuetong ZHANG ronghua HU Shumin YU Wenbin Open Research Laboratory of Geochemical Kinetics Chinese Academy of GeologicalSciences26 Baiwanzhuang RoadBeijing 100037

This work presents new experimental results on surface chemistry of reacting minerals and interface kinetics between mineral and aqueous solutions. These experiments were carried out using a flow reactor (packed bed reactor) of an open system as well as a continuous stirred tank reactor, CSTR. The authors measured reaction rates of such minerals as zeolite, albite and carbonate (rhodochrosite, dolomite) in various solutions, and tested corresponding mineral surface by using SEM, XPS, SIMS, etc. This paper mainly presents the experimental results of zeolite dissolution in water and in low pH solutions at room temperature, and dolomite dissolution at elevated temperatures. The results show that the release rates of Si, Al and Na of zeolite are different in most cases. The incongruent dissolution of zeolite is related to surface chemical modifications. The Na, Al and Si release rates for dissolution of albite and zeolite in water and various solutions were measured as a function of temperature, flow velocity, pH and solution composition in the reaction system. In most cases, dissolutions of both albite and zeolite are incongruent. Dissolution of dolomite is also incongruent in most cases and varied with T, pH, and nature of aqueous solutions. For dolomite dissolution, the release rates of Mg are less than those of Ca at high temperatures as T increases from 25 to 300°C. SIMS study indicates that the contents of Al, Na and Si in the leached layer of zeolite or albite surface, change with the distance from the surface, exhibiting a non-linear behaviour within a thickness range of 1000%. The distributions of Ca, Mg, Mn, H and Cl in the leached surface layer of carbonate have a non-linear behaviour too.

关键词： mineral surface kinetics liquid/solid interface reaction