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Reaction mode between Si and Fe and evaluation of optimal species in poly-silicic-ferric coagulant

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Journal of Environmental Sciences 2007年第6期19卷 678-688页

作者： FU Ying yu Shui-li yu yan-zhen QIU Li-ping HUI Ban School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China School of Civil and Architectural Engineering University of Jinan Jinan 250022 China Extraction the Fourth Factory Daqing Oilfield Company Ltd. Daqing 163113 China

A kind of Fe-polysilicate polymer, poly-silicic-ferric （PSF） coagulant was prepared by co-polymerization （hydroxylation of mixture of Fe^3＋ and fresh polysilicic acid （PS））, in which PSF0.5, PSF1 or PSF3 denotes Si/Fe molar ratio of 0.5, 1 or 3, respectively. The effects of Si/Fe ratio and reaction time （co-polymerization time or aging time） on the reaction mode between Si and Fe were studies, and the optimal species of PSF was evaluated by pH change during the preparation of PSF and coagulation tests. The results showed that the characteristics of PSF are largely affected by both reaction time and Si/Fe ratio. PSF is found to be a essential complex of Si, Fe, and many other ions. The reaction mode between Si and Fe differs with various Si/Fe ratios. The pH of PSF0.5, PSF1 or PSF3 tended to be stable when reaction time is 10, 25 or 55 rain, respectively, which is almost consistent with the time reaching the relative stable morphology that is just the optimal species of higher coagulation efficiency. The optimal reaction time reaching optimal species can be evaluated by measuring the pH change during the polymerization process.

关键词： poly-silicic-ferric coagulant reaction mode optimal species

Characteristics of anomalous Hall effect in spin-polarized two-dimensional electron gases in the presence of both intrinsic,extrinsic,and external electric-field induced spin-orbit couplings

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Chinese Physics B 2012年第2期21卷 469-476页

作者： Liu Song yan yu-zhen Hu Liang-Bin Laboratory of Quantum Information Technology School of Physics and Telecommunication EngineeringSouth China Normal UniversityGuangzhou 510631China

The various competing contributions to the anomalous Hall effect in spin-polarized two-dimensional electron gases in the presence of both intrinsic, extrinsic and external electric-field induced spin-orbit coupling were investigated theoretically. Based on a unified semiclassical theoretical approach, it is shown that the total anomalous Hall conductivity can be expressed as the sum of three distinct contributions in the presence of these competing spin-orbit interactions, namely an intrinsic contribution determined by the Berry curvature in the momentum space, an extrinsic contribution determined by the modified Bloch band group velocity and an extrinsic contribution determined by spin-orbit-dependent impurity scattering. The characteristics of these competing contributions are discussed in detail in the paper.

关键词： anomalous Hall effect intrinsic spin orbit coupling extrinsic spin orbit coupling exter- nal electric-field induced spin-orbit coupling

An Extended Extrinsic Mechanism for Anomalous Hall Effect

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Communications in Theoretical Physics 2009年第12期52卷 1129-1133页

作者： yan yu-zhen LI Hui-Wu HU Liang-Bin Laboratory of Quantum Information Technology School of Physics and Telecommunication Engineering South China Normal University Guangzhou 510631 China

The extrinsic mechanism for anomalous Hall effect in ferromagnets is extended to include the contributions both from spin-orbit-dependent impurity scattering and from the spin-orbit coupling induced by external electric fields. The results obtained suggest that, within the framework of the extrinsic mechanisms, the anomalous Hall current in a ferromagnet may also contain a substantial amount of dissipationless contribution independent of impurity scattering. After the contribution from the spin-orbit coupling induced by external electric fields is included, the total anomalous Hall conductivity is about two times larger than that due to soin-orbit dependent impurity scatterings.

关键词： anomalous Hall effect extrinsic mechanism spin-orbit coupling induced by external electric fields

Energy efficient TDMA-based MAC protocol associated with GAF for wireless sensor networks

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The Journal of China Universities of Posts and Telecommunications 2007年第1期14卷 6-11页

作者： XIAO Xiao zhenG Bao-yu yan zhen-ya CHEN Chao Institute of Signal and Information Processing Nanjing University of Posts and Telecommunications Nanjing 210003 China

The design of media access control （MAC） protocol for wireless sensor networks （CSNs） with the idea of cross layer attracts more and more attention. People can improve the MAC protocol by obtaining certain information regarding the network layer and physical layer. This article synthesizes and optimizes certain cross-layer protocols which have existed. On the basis of the muting, topology information in the network layer, and transmission power information in the physical layer, the thne slot assignment algorithm has been improved in the MAC layer. By using geographical adaptive fidelity algorithm （GAF） to divide the grids, controlling of transmission power and scheduling the work/sleep duty cycle for sensor nodes, a new MAC protocol has been proposed to decrease energy consumption and enlarge the lifetime of WSNs. Simulation results show that the MAC protocol functions well.

关键词： power controlled time division multiple access(TDMA) WSNs MAC GAF

Synthesis of novel chiral N,P-containing multidentate ligands and their applications in asymmetric transfer hydrogenation

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Chinese Chemical Letters 2011年第11期22卷 1269-1272页

作者： Shen Luan yu yan yun Li zhen Rong Dong Juan Ni Zhang Qi Li Jing Xing Gao State Key Laboratory of Physical Chemistry of Solid Surfaces National Engineering Laboratory for Green ChemicalProductions of Alcohols-Ethers-Esters and Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China

Novel chiral PN_4-type multidentate aminophosphine ligands have been successfully synthesized by Schiff-base condensation of bis（o-formylphenyl）phenylphosphane and various chiral *** structures were fully characterized by IR,EI-MS and *** catalytic systems,prepared in situ from the multidentate ligands and iridium（I） complexes,showed high activity in asymmetric transfer hydrogenation of propiophenone in 2-propanol solution,leading to corresponding optical alcohol with up to 75%ee.

关键词： Chiral multidentate aminophosphine ligand Iridium complex Propiophenone Asymmetric transfer hydrogenation

Integration of Electrical Properties and Polarization Loss Modulation on Atomic Fe–N‑RGO for Boosting Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第2期17卷 517-532页

作者： Kaili Zhang yuefeng yan zhen Wang Guansheng Ma Dechang Jia Xiaoxiao Huang yu Zhou State Key Laboratory of Precision Welding&Joining of Materials and Structures Harbin Institute of TechnologyHarbin 150001People’s Republic of China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001People’s Republic of China MIIT Key Laboratory of Advanced Structural‑Functional Integration Materials&Green Manufacturing Technology Harbin Institute of TechnologyHarbin 150001People’s Republic of China

Developing effective strategies to regulate graphene’s conduction loss and polarization has become a key to expanding its application in the electromagnetic wave absorption(EMWA)*** on the unique energy band structure of graphene,regulating its bandgap and electrical properties by introducing heteroatoms is considered a feasible ***,metal-nitrogen doping reduced graphene oxide(M–N-RGO)was prepared by embedding a series of single metal atoms M–N_(4) sites(M=Mn,Fe,Co,Ni,Cu,Zn,Nb,Cd,and Sn)in RGO using an N-coordination atom-assisted *** composites had adjustable conductivity and polarization to optimize dielectric loss and impedance matching for efficient EMWA *** results showed that the minimum reflection loss(RL_(min))of Fe–N-RGO reaches−74.05 dB(2.0 mm)and the maximum effective absorption bandwidth(EAB_(max))is 7.05 GHz(1.89 mm)even with a low filler loading of only 1 wt%.Combined with X-ray absorption spectra(XAFS),atomic force microscopy,and density functional theory calculation analysis,the Fe–N_(4) can be used as the polarization center to increase dipole polarization,interface polarization and defect-induced polarization due to d-p orbital hybridization and structural ***,electron migration within the Fe further leads to conduction loss,thereby synergistically promoting energy *** study demonstrates the effectiveness of metal-nitrogen doping in regulating the graphene′s dielectric properties,which provides an important basis for further investigation of the loss mechanism.

关键词： Electromagnetic wave absorption Fe-N-RGO Dipole polarization Conduction loss Impedance matching

Changes to the Natural Regional Boundaries in China During 1961-2007

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Atmospheric and Oceanic Science Letters 2011年第4期4卷 199-203页

作者： yu zhen-yan FAN Guang-Zhou DONG Yi-Ping WANG Lei HUA Wei ZHOU Ding-Wen Zhejiang Climate Center Hangzhou 310017 China College of Atmospheric Sciences Chengdu University of Information Technology （CULT） Chengdu 610225 China

Daily temperature data from 599 stations across China for the years 1961 to 2007 were used to analyze the changes in the natural regional boundaries. The results show that the accumulated temperature ≥10℃ and its duration changed dramatically from the end of 1990s to the early 21 st century. The amplitude of natural regional boundaries was greater in the 21st century than it was in the 20th century. In the eastern region of China, the climatic zones were migrating generally northward, with the northern edge of the subtropical zone and the eastern section of the warm temperate zone showing an obvious northward shift of up to 1-3° of latitude. The climatic zones moved south in the Qinghal-Tibet Plateau, western Inner Mongolia, and some areas of western Xinjiang, and slightly to the north in other parts of the western region.

关键词： accumulated temperature duration natural regional boundary global warming

Dynamic Regulation of Hydrogen Bonding Networks and Solvation Structures for Synergistic Solar‑Thermal Desalination of Seawater and Catalytic Degradation of Organic Pollutants

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Nano-Micro Letters 2025年第2期17卷 548-565页

作者： Ming‑yuan yu Jing Wu Guang Yin Fan‑zhen Jiao Zhong‑zhen yu Jin Qu Beijing Key Laboratory of Advanced Functional Polymer Composites Beijing University of Chemical TechnologyBeijing 100029People’s Republic of China State Key Laboratory of Organic‑Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029People’s Republic of China

Although solar steam generation strategy is efficient in desalinating seawater,it is still challenging to achieve continuous solar-thermal desalination of seawater and catalytic degradation of organic ***,dynamic regulations of hydrogen bonding networks and solvation structures are realized by designing an asymmetric bilayer membrane consisting of a bacterial cellulose/carbon nanotube/Co_(2)(OH)_(2)CO_(3)nanorod top layer and a bacterial cellulose/Co_(2)(OH)_(2)CO_(3)nanorod(BCH)bottom ***,the hydrogen bonding networks inside the membrane can be tuned by the rich surface–OH groups of the bacterial cellulose and Co_(2)(OH)_(2)CO_(3)as well as the ions and radicals in situ generated during the catalysis ***,both SO_(4)^(2−)and HSO_(5)−can regulate the solvation structure of Na^(+)and be adsorbed more preferentially on the evaporation surface than Cl^(−),thus hindering the de-solvation of the solvated Na^(+)and subsequent nucleation/growth of ***,the heat generated by the solar-thermal energy conversion can accelerate the reaction kinetics and enhance the catalytic degradation *** work provides a flow-bed water purification system with an asymmetric solar-thermal and catalytic membrane for synergistic solar thermal desalination of seawater/brine and catalytic degradation of organic pollutants.

关键词： Solar steam generation Seawater desalination Catalytic degradation Bacterial cellulose Cobalt hydroxycarbonate nanorods

Enhanced CT and CT virtual endoscopy in diagnosis of heterotopic pancreas

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World Journal of Gastroenterology 2011年第33期17卷 3850-3855页

作者： Dan Wang Xiao-Er Wei Lei yan yu-zhen Zhang Wen-Bin Li Institute of Diagnostic and Interventional Radiology The Sixth Affiliated People＇s HospitalShanghai Jiao Tong UniversityShanghai 200233China

AIM:To improve the diagnosis of heterotopic pancreas by the use of contrastenhanced computed tomography(CT)imaging and CT virtual endoscopy(CTVE).METHODS:A total of six patients with heterotopic pancreas,as confirmed by clinical pathology and immunohistochemistry in the Sixth Affiliated People's Hospital of Shanghai Jiao Tong University,Shanghai,China,were *** CT and enhanced CT scanning were performed,and the resulting images were reviewed and analyzed using threedimensional postprocessing software,including ***:Four males and two females were *** heterotopic pancreas sites were involved;three occurred in the stomach,including the gastric antrum(n =2)and lesser curvature(n=1),and two were in the duodenal *** one case of heterotopic pancreas lesion occurred in the *** cases had a solid yet soft tissue density that had a homogeneous pattern when viewed by enhanced ***,their CT values were similar to that of the *** ducts of the heterotopic pancreas tissue,one of the characteristic CT features of heterotopic pancreas tissue,were detected in the CT images of two *** images showed normal mucosa around the tissue,which is also an important indicator of a heterotopic ***,none of the CTVE images showed the typical signs of central dimpling or ***:CT,enhanced CT and CTVE techniques provide useful information about the location,growth pattern,vascularity,and condition of the gastrointestinal wall around heterotopic pancreatic tissue.

关键词： Heterotopic pancreas Computed tomography Contrast enhancement Computed tomography virtual endoscopy