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Synthesis and cationic selectivity studies of novel calix[4]arene derivatives containing heteroatom at the lower rim

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Science China Chemistry 2007年第5期50卷 654-659页

作者： WANG Hao LI zhe liu Yu State Key Laboratory of Elemento-Organic Chemistry Department of Chemistry Nankai University Tianjin 300071 China State Key Laboratory of Elemento-Organic Chemistry Department of Chemistry Nankai University Tianjin 300071 China State Key Laboratory of Elemento-Organic Chemistry Department of Chemistry Nankai University Tianjin 300071 China

A series of calixarene derivatives 2―5 containing heteroatom at the lower rim have been synthesized. 1H NMR studies and crystallographic structures demonstrated that the calix[4]arene derivatives adopted cone conformations. Their cationic binding abilities and selectivities towards heavy and tran- sition metal ions have been evaluated by solvent extraction of aqueous metal picrates. The obtained results indicated that the introduction of nitrogen, sulfur, and/or phosphor atoms to the calix[4]arene framework could effectively enhance their binding ability and selectivity for heavy and transition metal ions, such as Pb2+ or Ag+.

关键词： calixarene, synthesis, cationic selectivity, solvent extraction

Pentavalent Symmetric Graphs of Order Twice a Prime Square

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Algebra Colloquium 2015年第3期22卷 383-394页

作者： Jiangmin Pan zhe liu Xiaofen Yu Department of Mathematics Yunnan University of Finance and Economics Kunming 650221 China College of Science Zhejiang Agriculture and Forestry University Hangzhou 311300 China Department of Mathematics Yunnan University Kunming 650031 China

A classification of pentavalent symmetric graphs of order twice a prime square is given. It is proved that such a graph is a coset graph of Z3.A6 （non-split extension）, or a bi-coset graph of an extra-special group ... 详细信息

关键词： symmetric graph Cayley graph standard double cover automorphism group

Novel Approach for Automatic Region of Interest and Seed Point Detection in CT Images Based on Temporal and Spatial Data

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Computers, Materials & Continua 2019年第5期59卷 669-686页

作者： zhe liu Charlie Maere Yuqing Song School of Computer Science and Telecommunication Jiangsu UniversityZhenjiangChina

Accurately finding the region of interest is a very vital step for segmenting organs in medical image *** propose a novel approach of automatically identifying region of interest in Computed Tomography Image(CT)images based on temporal and spatial *** method is a 3 stages approach,1)We extract organ features from the CT images by adopting the Hounsfield filter.2)We use these filtered features and introduce our novel approach of selecting observable feature candidates by calculating contours’area and automatically detect a seed point.3)We use a novel approach to track the growing region changes across the CT image sequence in detecting region of interest,given a seed point as our *** used quantitative and qualitative analysis to measure the accuracy against the given ground truth and our results presented a better performance than other generic approaches for automatic region of interest detection of organs in abdominal CT *** the results presented in this research work,our proposed novel sequence approach method has been proven to be superior in terms of accuracy,automation and robustness.

关键词： Computed tomography image continuously adaptive mean-shift hounsfield particle-size distribution

Continuity for Maximal Multilinear Bochner-Riesz Operators on Hardy and Herz Hardy Spaces

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Acta Mathematica Sinica,English Series 2006年第1期22卷 69-76页

作者： Lan zhe liu Shan zhen LU Department of Mathematics Changsha University of Science and Technology Changsha 410077 P. R. China Department of Mathematics Beijing Normal University Beijing 100875 P. R. China

Let Baδ^A. be the maxiamal multilinear Bochner-Riesz operators generated by Bochner Riesz operators and D^αA∈ Lipβ（｜α｜= m）, The continuity of the operator on some Hardy and Herz type Hardy is obtained.

关键词： Bochner-Riesz operator Multilinear Operators Hardy Space Herz Space Lipschitz space

Wavelength dimensioning for wavelength-routed WDM satellite network

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Chinese Journal of Aeronautics 2016年第3期29卷 763-771页

作者： liu zhe Guo Wei Deng Changlin Hu Weisheng State Key Lab of Advanced Optical Communication Systems and Networks Shanghai Jiao Tong University

Internet and broadband applications driven by data traffic demand have become key dri- vers for satellite constellations. The key technology to satisfy the high capacity requirements between satellites is optical satellite networks by means of wavelength division multiplexing inter- satellite links （ISLs） with wavelength routing （WDM-OSN）. Due to the limited optical amplifier bandwidth onboard the satellite, it is important to minimize the wavelength requirements to provi- sion requests. However, ISLs should be dynamically established and deleted for each satellite according to its visible satellites. Furthermore, different link assignments will result in different topologies, hence yielding different routings and wavelength assignments. Thus, a perfect match model-based link assignment scheme （LAS-PMM） is proposed to design an appropriate topology such that shorter path could be routed and less wavelengths could be assigned for each ISL along the path. Finally, simulation results show that in comparison to the regular Manhattan street net- work （MSN） topology, wavelength requirements and average end-to-end delay based on the topol- ogy generated by LAS-PMM could be reduced by 24.8% and 12.4%, respectively.

关键词： LAS LAS-PMM Routing Wavelength assignment Wavelength dimensioning WDM-OSN

Functional micro/nanobubbles for ultrasound medicine and visualizable guidance

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Science China Chemistry 2021年第6期64卷 899-914页

作者： Chen Zhang Yihong Li Xinyong Ma Wenxin He Chenxi liu zhe liu Academy of Medical Engineering and Translational Medicine Tianjin UniversityTianjin 300072China Tianjin Key Laboratory of Brain Science and Neural Engineering Tianjin UniversityTianjin 300072China Division of Academic&Cultural Activities Academic Divisions of the Chinese Academy of SciencesBeijing 100190China

Chemically functionalized gas-filled bubbles with a versatile micro/nano-sized scale have witnessed a long history of developments and emerging applications in disease diagnosis and *** combination with ultrasound and image-guidance,micro/nanobubbles have been endowed with the capabilities of biomedical imaging,drug delivery,gene transfection and diseaseoriented *** an external stimulus,ultrasound(US)-mediated targeting treatments have been achieving unprecedented ***,US is playing a crucial role in visualizing biological/pathological changes in lives as a reliable imaging technique and a powerful therapeutic *** review retrospects the history of ultrasound,the chemistry of functionalized agents and summarizes recent advancements of functional micro/nanobubbles as US contrast agents in preclinical and transclinical *** ultrasound-based treatment modalities in association with functional micro/nanobubbles have been highlighted as their great potentials for disease precision *** is believed that these state-of-the-art micro/nanobubbles will become a booster for ultrasound medicine and visualizable guidance to serve future human healthcare in a more comprehensive and practical manner.

关键词： ultrasound functional biomaterials image guidance visualizable medicine drug delivery

Formation and strengthening mechanism of kink bands in an ultra-coarse-grained Fe-Cr-Al alloy

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Journal of Materials Science & Technology 2024年第19期186卷 1-14页

作者： Wei Luo Teng Xue Ding Zuo Jingze Cheng zhe liu Huiqun liu School of Materials Science and Engineering Central South UniversityChangsha 410083China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

Fe-Cr-Al alloys,owing to their absence of allotropic transformation,require multiple cycles of rolling and recrystallization annealing processes to achieve substantial grain refinement,ultimately leading to the attainment of outstanding mechanical ***,the corresponding manufacturing costs will also increase *** this work,we have proposed a new microstructural preparation ***-ply using warm rolling for an ultra-coarse-grained Fe-Cr-Al alloy to introduce lamellar kink bands(KBs)into the matrix,the mechanical properties can be significantly *** using electron backscatter diffraction(EBSD)and transmission electron microscopy(TEM),and combined with Schmid factor(SF)calculation,the formation mechanism of KBs has been *** the slip plane and direction are nearly perpendicular to the loading force direction(LFD)during the continuous grain rotation,the dislo-cation wall will evolve into the KBs ***,a huge orientation separation between the matrix and KBs will be *** strain continues to rise,KBs undergo a transformation,tran-sitioning from low-angle-grain boundaries(LAGBs)to high-angle-grain boundaries(HAGBs),occasionally adopting a configuration as coincident site lattice(CSL)boundaries with reduced interface ***-sults of the tensile test,cyclic loading-unloading-reloading tensile test,and the strengthening calculation show that KBs can pronouncedly enhance the strength by their heterogeneous refinement on the original grains and hetero-deformation induced(HDI)strengthening effect from the dislocation density discrep-ancy between the matrix and internal KBs,the grains containing KBs(KBGs)and the grains without KBs(or KBs-free-grains,KFGs).The theoretical calculation value of the strengthening contribution from KBs on yield strength can be up to 225.5 MPa,with a minimum value exceeding 153 *** the other hand,the ductility can be retained to some extent through stimulating the KBs boundary de

关键词： Fe-Cr-Al alloy Kink bands(KBs) Heterogenous refinement Hetero-deformation induced(HDI) strengthening KBs boundary delamination

Homological dimensions of gentle algebras via geometric models

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Science China Mathematics 2024年第4期67卷 733-766页

作者： Yu-zhe liu Hanpeng Gao Zhaoyong Huang Department of Mathematics Nanjing UniversityNanjing 210093China School of Mathematical Sciences Anhui UniversityHefei 230601China

Let A=kQ/I be a finite-dimensional basic algebra over an algebraically closed field k,which is a gentle algebra with the marked ribbon surface(SA,MA,ΓA).It is known that SAcan be divided into some elementary polygons{Δi|1≤i≤d}byΓA,which has exactly one side in the boundary of ***■(Δi)be the number of sides ofΔibelonging toΓAif the unmarked boundary component of SAis not a side ofΔi;otherwise,■(Δi)=∞,and let f-Δbe the set of all the non-co-elementary polygons and FA(resp.f-FA)be the set of all the forbidden threads(*** finite length).Then we have(1)the global dimension of A is max1≤i≤d■(Δi)-1=maxΠ∈FAl(Π),where l(Π)is the length ofΠ;(2)the left and right self-injective dimensions of A are 0,if Q is either a point or an oriented cycle with full ***Δi∈f-Δ{1,■(Δi)-1}=max n∈f-F_(A)l(П),otherwise,As a consequence,we get that the finiteness of the global dimension of gentle algebras is invariant under AvellaGeiss(AG)-*** addition,we get that the number of indecomposable non-projective Gorenstein projective modules over gentle algebras is also invariant under AG-equivalence.

关键词： global dimension self-injective dimension gentle algebras marked ribbon surfaces geometric models AG-equivalence

Preparation and Effectiveness of Slow-release Polymeric Fertilizer Containing Multiple Nutrients Special for Maize

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高校化学工程学报 2007年第3期21卷 477-480页

作者： ZHAO Gui-zhe liu Ya-qing ZHANG Bin Research Center for Engineering Technology of Polymeric Composites of Shanxi Province College of Materials Science and Engineering North University of China Taiyuan 030051 China

Slow-release polymeric fertilizer containing multiple nutrients was synthesized through condensation polymerization from raw materials of homemade low-molecular urea-formaldehyde and the compounds of potassium dihydrogen phosphate and phosphoric acid. Adjustment of the proportion of raw materials makes the ingredients of the fertilizer are N:P_2O_5:K_2O =1:0.75:0.13, which satisfy the nutritional requirement for maize growth. Field-experiment results prove that the yield of maize increases by 16.56% when using the polymeric fertilizer special for maize alone, by 56.51% when applying the polymeric fertilizer special for maize plus farmyard manure, and by 49.11% when applying the SV fertilizer special for maize plus manure.

关键词：玉米缓释肥料复合肥制备肥效田间试验