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International Journal of minerals,Metallurgy and Materials 2012年第1期19卷 9-14页

作者： yu-min Liu Hua Lv Tao Qi Yi Zhang College of Chemistry and Environmental Science Henan Normal University Xinxiang 453007 China Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 China

To effectively utilize ilmenite and recycle KOH solution, the extraction behaviours of titanium and other associated impurities in the decomposition process of ilmenite by highly concentrated KOH solution were studied. Experiments on the extraction behaviours of tita- nium as well as other associated impurities of ilmenite such as iron, silicon, calcium, and aluminium were carried out. The effects of various parameters, including reaction temperature, KOH concentration, reaction time, alkali-to-ore mass ratio, and particle size on the extraction rate of titanium and other impurities were examined. When the finely ground ore （58-75 ~tm） reacted with KOH solution （80wt%） in an al- kali-to-ore mass ratio of 7：1 at 260~C for 60 min, almost complete extraction of titanium was achieved, while the extraction rate of aluminium was 78% and that of other impurities was less than 22%. Moreover, high purity （98.2wt%） TiO2 with the anatase structure could be gained in the purification process.

关键词： ilmenite titanium dioxide potassium hydroxide leaching

Analysis of bacterial community structures in two sewage treatment plants with different sludge properties and treatment performance by nested PCR-DGGE method

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Journal of Environmental Sciences 2007年第1期19卷 60-66页

作者： LIU Xin-chun ZHANG yu YANG min WANG Zhen-yu LV Wen-zhou State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beifing 100085 China

The bacterial community structures in two sewage treatment plants with different processes and performance were investigated by denaturing gradient gel electrophoresis （DGGE） of nested polymerase chain reaction （nested PCR） amplified 16S rRNA gene fragments with group-specific primers. Samples of raw sewage and treated effluents were amplified using the whole-cell PCR method, and the activated sludge samples were amplified using the extracted genomic DNA before the PCR products were loaded on the same DGGE gel for bacterial community analysis. Ammonia-oxidizing bacterial and actinomycetic community analysis were also carried out to investigate the relationship between specific population structures and system or sludge performance. The two plants demonstrated a similarity in bacterial community structures of raw sewage and activated sludge, but they had different effluent populations. Many dominant bacterial populations of raw sewage did not appear in the activated sludge samples, suggesting that the dominant bacterial populations in raw sewage might not play an important role during wastewater treatment. Although the two plants had different sludge properties in terms of settleability and foam forming ability, they demonstrated similar actinomycetic community structures. For activated sludge with bad settling performance, the treated water presented a similar DGGE pattern with that of activated sludge, indicating the nonselective washout of bacteria from the system. The plant with better ammonium removal efficiency showed higher ammonia-oxidizing bacteria species richness. Analysis of sequencing results showed that the major populations in raw sewage were uncultured bacterium, while in activated sludge the predominant populations were beta proteobacteria.

关键词： activated sludge wastewater treatment sewage community analysis PCR-DGGE

The Pedagogy of Place in China's Migrant Community

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ECNU Review of Education 2024年第3期7卷 554-572页

作者： min yu Wayne State University

Purpose:This article examines the curriculum and pedagogy of place for migrant children in China and advocates the recognition of migrant families'and communities'knowledge as neces-sary,relevant,and impactful ***/Approach/Methods:This article is based on a longitudinal qualitative study conducted in various migrant settlements in *** were collected from in-depth interviews with migrant parents,teachers,and community activists and participant observations in schools,com-munity meetings,and other gatherings in the *** were coded on themes related to place-based connection,attachment,and belonging and then ***:Findings demonstrate that pedagogical practices can be developed to re-center the knowledge and experiences of Chinese migrant *** pedagogical work recognizes and reflects the undervalued and unrecognized knowledge of migrant communities while investi-gating the meaning of“place”for migrant ***:This is the first study putting special emphasis on the discussion of what“place”means for migrants and what knowledge is worthwhile for their children in China.A key contribution of this article is that it documents the challenges and benefits of creating a place-based curriculum and pedagogy for migrant children as they construct a sense of belonging.

关键词： Belonging core/periphery structure migrant children pedagogy of place place-based rural-urban divide

Bioinspired Underwater Navigation Using Polarization Patterns Within Snell’s Window

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China Ocean Engineering 2023年第4期37卷 628-636页

作者： CHENG Hao-yuan yu Shi-min yu Hao ZHU Jin-chi CHU Jin-kui Department of Mechanical and Electrical Engineering Ocean University of ChinaQingdao 266100China Key Laboratory of Ocean Engineering of Shandong Province Ocean University of ChinaQingdao 266100China Key Laboratory for Micro/Nano Technology and System of Liaoning Province Dalian University of TechnologyDalian 116024China

Aiming at the requirement of autonomous navigation capability of the underwater unmanned vehicle(UUV),a novel bionic method for underwater navigation based on polarization pattern within Snell’s window is *** by creatures,polarization navigation is a satellite-free navigation scheme and has great potential to be used in the ***,because of the complex underwater environment,whether UUV polarization navigation can be realized is *** illustrate the feasibility of underwater polarization navigation,we firstly establish the model of under-water polarization patterns to prove the stability and predictability of the underwater polarization pattern within Snell’s ***,we carry out static and dynamic experiments of underwater heading determination based on developed polarization information detection ***,we obtain underwater polarization patterns and conduct the tracking experiment at different water *** experimental results of the underwater polarization patterns are consistent with the simulation,which proves the correctness of the proposed *** the water depth of 5 m,the average angle and position error of the tracking experiment are 14.3508°and 4.0812 m,*** is illustrated that underwater polarization navigation is realizable and the precision can meet the real-time navigation requirements of *** study promotes the improvement of underwater navigation ability and the development of marine equipment.

关键词： underwater navigation polarization pattern heading determination tracking experiment

Cu,N codoped carbon nanosheets encapsulating ultrasmall Cu nanoparticles for enhancing selective 1,2-propanediol oxidation

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Journal of Energy Chemistry 2024年第4期91卷 27-35页

作者： Yonghai Feng min yu minjia Meng Lei Liu Dewei Rao Institute for Advanced Materials School of Materials Science and EngineeringJiangsu UniversityZhenjiang 212013JiangsuChina School of Chemistry and Chemical Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

In the selective oxidation of biomass-based 1,2-propanediol(PDO)with oxygen as the terminal oxidant,it is challenging to improve the lactic acid(LA)selectivity for nonnoble metal nanoparticles(NPs)due to their limited oxygen reduction rate and easy C-C *** the high economic feasibility of nonnoble metals,i.e.,Cu,in this work,copper and nitrogen codoped porous carbon nanosheets encapsulating ultrafine Cu nanoparticles(Cu@Cu-N-C)were developed to realize highly selective of PDO oxidation to *** carbon-encapsulated ultrasmall Cu^(0)NPs in Cu@Cu-N-C have high PDO dehydrogenation activity while N-coordinated Cu(Cu-N)sites are responsible for the high oxygen reduction ***,the performance of catalytic PDO conversion to LA is optimized by a proposed pathway of PDO→hydroxylacetone→lactaldehyde→***,the enhanced LA selectivity is 88.5%,and the PDO conversion is up to 75.1%in an O_(2)-pressurized reaction system(1.0 MPa O_(2)),superior to other Cu-based catalysts,while in a milder nonpressurized system(O_(2)flow rate of 100 mL min-1),a remarkable LA selectivity(94.2%)is obtained with 39.8%PDO conversion,2.2 times higher than that of supported Au nanoparticles(1%Au/C).Moreover,carbon encapsulation offers Cu@Cu-N-C with strong leaching resistance for better recycling.

关键词： Selective oxidation Copper and nitrogen doped carbon 1,2-Propanediol Ultrasmall Cu nanoparticles Lactic acid

Application of Active Contour Model in Tracking Sequential Nearshore Waves

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China Ocean Engineering 2009年第2期23卷 251-266页

作者： yu-Hung HSIAO min-Chih HUANG Department of Systems and Naval Mechatronic Engineering National Cheng Kung University Tainan 701 China

In the present study, a generalized active contour model of gradient vector flow is combined with the video techniques of Argus system to delineate and track sequential nearshore wave crest profiles in the shoaling process, up to their breaking on the shoreline. Previous applications of active contour models to water wave problems are limited to controllable wave tank experiments. By contrast, our application in this study is in a nearshore field environment where oblique images obtained under natural and varying condition of ambient light are employed. Existing Argus techniques produce plane image data or time series data from a selected small subset of discrete pixels. By contrast, the active contour model produces line image data along continuous visible curves such as wave crest profiles. The combination of these two existing techniques, the active contour model and Argus methodologies, facilitates the estimates of the direction wave field and phase speeds within the whole area covered by camera. These estimates are useful for the purpose of inverse calculation of the water depth. Applications of the present techniques to Hsi-tzu bay where a beach restoration program is currently undertaken are illustrated. This extension of Argus video techniques provides new application of optical remote sensing to study the hydrodynamics and morphology of a nearshore environment.

关键词： active contour model snake video images nearshore

Bilateral U-Net semantic segmentation with spatial attention mechanism

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CAAI Transactions on Intelligence Technology 2023年第2期8卷 297-307页

作者： Guangzhe Zhao Yimeng Zhang Maoning Ge min yu Beijing University of Civil Engineering and Architecture College of Electrical and Information EngineeringBeijingChina Graduate School of Informatics Nagoya UniversityNagoyaJapan Department of General Surgery Guangdong Provincial People's HospitalGuangdong Academy of Medical SciencesGuangzhouChina

Aiming at the problem that the existing models have a poor segmentation effect on imbalanced data sets with small-scale samples,a bilateral U-Net network model with a spatial attention mechanism is *** model uses the lightweight MobileNetV2 as the backbone network for feature hierarchical extraction and proposes an Attentive Pyramid Spatial Attention(APSA)module compared to the Attenuated Spatial Pyramid module,which can increase the receptive field and enhance the information,and finally adds the context fusion prediction branch that fuses high-semantic and low-semantic prediction results,and the model effectively improves the segmentation accuracy of small data *** experimental results on the CamVid data set show that compared with some existing semantic segmentation networks,the algorithm has a better segmentation effect and segmentation accuracy,and its mIOU reaches 75.85%.Moreover,to verify the generality of the model and the effectiveness of the APSA module,experiments were conducted on the VOC 2012 data set,and the APSA module improved mIOU by about 12.2%.

关键词： attention mechanism receptive field semantic fusion semantic segmentation spatial attention module U-Net

Certificateless universal designated verifier signature schemes

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The Journal of China Universities of Posts and Telecommunications 2007年第3期14卷 85-90,94页

作者： minG Yang SHEN Xiao-qin WANG yu-min State Key Laboratory of Integrated Service Network Xidian UniversityXi'an 710071 China

Universal designated verifier signature schemes allows a signature holder to designate the signature to a desire designated verifier, in such a way that only designated verifier can verify this signature, but is unable to convince anyone else of this fact. The previous constructions of universal designated verifier signature rely on the underlying public key infrastructure, that needs both signers and verifiers to verify the authenticity of the public keys, and hence, the certificates are required. This article presents the first model and construction of the certificateless universal designated verifier signature scheme, in which the certificates are not needed. The proposed scheme satisfies all the requirements of the universal designated verifier signature in the certificateless system. Security proofs are provided for the scheme based on the random oracle model, assuming that the Bilinear diffie-hellman （BDH） problem is hard to solve.

关键词： certificateless cryptography universal designated verifier signature bilinear pairing

Identity-based encryption with wildcards in the standard model

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The Journal of China Universities of Posts and Telecommunications 2009年第1期16卷 64-68,80页

作者： minG Yang SHEN Xiao-qin WANG yu-min School of Information Engineering Chang'an University Xi'an 710064 China ZTE Corporation Xi'an 710065 China State Key Laboratory of Integrated Service Network Xidian University Xi'an 710071 China

In this article, based on Chatterjee-Sarkar＇ hierarchical identity-based encryption （HIBE）, a novel identity-based encryption with wildcards （WIBE） scheme is proposed and is proven secure in the standard model （without random oracle）. The proposed scheme is proven to be secure assuming that the decisional Bilinear Diffie-Hellman （DBDH） problem is hard. Compared with the Wa-WIBE scheme that is secure in the standard model, our scheme has shorter common parameters and ciphertext length.

关键词： encryption identity-based encryption with wildcards bilinear pairing

Quantum XY Spin Glass Model with Longitudinal Ferromagnetic Coupling

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Chinese Physics Letters 1999年第5期16卷 378-380页

作者： SHANG yu-min YAO Kai-lun Department of Physics Huazhong University of Science and Technology Wuhan 430074 CCAST(World Laboratory) P.O.Box 8730Beijing 100080 International Center for Material Physics Chinese Academy of SciencesShenyang 110015

The quantum XY spin glass model with longitudinal ferromagnetic coupling is investigated in static replica symmetry *** thermodynamic quantities are calculated *** find that the ferromagnetic coupling enhances the stability of replica symmetric solution.A 2-dimensional Ising model like transition is found,which demonstrates that the ferromagnetic coupling increases the order of spin glass *** by the ferromagnetic coupling,transverse component of the susceptibility has two cusps corresponding to transverse-longitudinal spin-glass phase transition and longitudinal spin glass-paramagnetic transition separately.

关键词： solution. ferromagnetic coupling