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Open Journal of Inorganic Chemistry 2011年第2期1卷 9-15页

作者： M. A. Subhan S. A. Monim M. B. R. Bhuiyan A. N. Chowdhury M. Islam M. A. Hoque 不详

The multi-component oxide (Al0.88Fe0.67Zn0.28O3)) surface (abbreviated as MCOS) was prepared to optimize the effectiveness of the elimination of As (III) from aqueous solution. The oxide surface was synthe-sized by co-precipitation method using corresponding metal carbonates. It was characterized by XRD, TGA and DSC. The surface morphology of MCOS was observed in SEM and the elemental analysis was accomplished by EDX. The composition of Al2O3, Fe2O3 & ZnO was 23.6, 39.9 and 20.6 wt% respectively in XRF analysis. The specific surface area was found 389.85 m2 g-1. Batch experiments were performed to remove As (III) from aqueous solution considering various parameters such as effect of pH, contact time, initial arsenic concentration, temperature and sor-bent dosage. The maximum sorption capacity of the surface was almost steady from pH 4 to pH 9. Kinetic study shows that As (III) sorption is following second order rate equation with the rate constant of 80×10-2 g mg-1 min-1 at room temperature and this rate was increased with increasing temperature which indicates the sorption was endothermic process. The free energy change, ΔGo was negative which proves that the sorption was spontaneous and thermodynamically favorable. Sorption isotherm was interpreted by Langmuir equation and the maximum sorption capacity of oxide monolayer was 13×10-2 mg g-1.

关键词： As (III) multi-component Oxide Surface Sorption Sorbent Dosage

Microstructure and Properties of multi-component AlxCoCrFeNiTi0.5 High-entropy Alloys

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Microstructure and Properties of Multi-component AlxCoCrFeNi...

Dual-assisted high-precision tracking technique for wideband multiplexed signals in new generation GNSS

中国材料大会2012

作者： Yong Dong Yiping Lu Junjia Zhang Tingju Li School of Materials Science and Engineering Dalian University of Technology

ISBN: (纸本)9783037856079

The multi-component AlxCoCrFeNiTi0.5 （x=0, 0.2, 0.5, 0.8, 1.0） high-entropy alloys were prepared by vacuum arc melting. The microstructure and mechanical properties were studied. It was found that the structure transformed from FCC into FCC + BCC + Laves, and finally into BCC with the increase of Al content. The compress test results showed that with the addition of aluminium from 0 to 1.0, the fraction strength increased while plasticity reduced. In the stain rates of 5×10-3 /s and 1×10-3 /s, when x=0.8 the fraction strength achieved maximum and x=0 the plastic was best, the strength of 2879MPa and 2433MPa, the strain of 0.21 and 0.22, respectively. The hardness increased obviously （from Hv479.1 to Hv692.7） when Bcc phase and Laves phase appeared. The analysis revealed that the strengthen mechanism was mainly composed of solid solution strengthening and precipitation strengthening.

关键词： multi-component High-entropy alloys Microstructure Solid solution Fracture strength

来源： cnki会议评论

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Satellite Navigation 2024年第1期5卷 52-73页

作者： Yunhan Qi Zheng Yao Mingquan Lu Department of Electronic Engineering Tsinghua UniversityBeijing100084China Beijing National Research Center for Information Science and Technology Beijing100084China

With the evolution of Global Navigation Satellite System(GNSS),new generation GNSS signals have adopted the dual-frequency multiplexing modulation techniques,which jointly modulate multiple signals located on multiple sub-frequencies into a Wideband multiplexed Signal(WMS).Although WMSs were proposed initially to reduce the complexity of satellite transmitters and improve the transmission efficiency of signals,their multi-component structures and wide root mean square bandwidths introduced by high-frequency subcarriers also provide the possibility to improve the GNSS ranging ***,this paper proposes a Dual-assisted multi-component Tracking(DMT)technique,which can not only fully use high-frequency subcarriers in WMSs,but also effectively track carrier,subcarrier,and code by jointly utilizing all components in *** this paper,the tracking and ranging performances of DMT are comprehensively analyzed theoretically and by simulation and real *** results show that compared with existing WMS tracking methods,DMT can achieve tracking results with lower tracking jitters and ranging results with higher precision,providing a highly advantageous solution for new generation GNSS signal processing.

关键词： Wideband multiplexed signal Dual-assisted multi-component High precision tracking

Assembly of peptide nanostructures with controllable sizes

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Nano Research 2024年第1期17卷 151-161页

作者： Dan Cheng Fan Jia Yun-Bao Jiang Vincent P.Conticello Tao Jiang The MOE Key Laboratory of Spectrochemical Analysis and Instrumentation Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM) Xiamen 361005China Department of Chemistry Emory UniversityAtlanta 30033USA

Controlled peptide assembly offers significant promise to develop synthetic supramolecular nanostructures to display material and biological properties that mimic protein assemblies in *** the progress in forming peptide nanostructures of various morphology,there exists a distinct gap between natural and synthetic assembly systems in terms of size *** nanostructures with a narrow size distribution that can be tuned over a wide range of length-scales is essential for applications that require precise spacing between *** approach provides the opportunity to correlate materials and biological properties of interest with assembly *** this review,we discuss representative endeavors over the past two decades for design of size-controllable peptide nanostructures using tunable building *** mechanisms for size control,e.g.,molecular frustration,template-directed peptide assembly,and multi-component peptide co-assembly,will also be *** also demonstrate the applicable scopes of these strategies and suggest potential future avenues for scientific advances in this field.

关键词： peptide assembly controllable size template multi-component

Fully fluorinated hybrid zeolite imidazole/Prussian blue analogs with combined advantages for efficient oxygen evolution reaction

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Chinese Chemical Letters 2024年第6期35卷 222-228页

作者： Jiayu Xu Meng Li Baoxia Dong Ligang Feng School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China

Hybrid metal-organic framework(MOF)derivatives play a significant role in the novel catalyst development in energy conversion ***,we demonstrated the low-temperature fully fluorinated zeolitic imidazole framework(ZIF)coupled with a three-dimensional open framework Prussian blue analog(PBA)with combined advantages for electrocatalytic oxygen evolution reaction(OER)in water splitting *** spectroscopic analysis and the electrochemical studies revealed the combined advantages of efficient electronic effect and active site *** of good conductivity improvement by Ndoped carbon derived from ZIF and the high electrochemical surface area and active site exposure from PBA derivatives,good catalytic performance was obtained on the optimal catalyst of Co Ni ZIF/Co Fe-PBAF-300,which required a low overpotential of 250 m V to reach 10 m A/cm^(2)loaded on the glassy carbon electrode,with Tafel slope of 47.4 m V/dec,and very high dynamic and steady *** addition,the multi-component with the mixed structure from highly polar metal fluorides promoted the easy formation of the active phase as revealed by the post-sample *** current results showed a novel composite catalyst materials development from the hybrid MOF derivatives,which would be promising in the electrolysis of water oxidation reactions and energy-relevant catalysis reactions.

关键词： Metal-organic framework Zeolitic imidazole framework Prussian blue analog Fluoridation multi-component Oxygen evolution reaction

Coupling of ultrasmall and small CoxP nanoparticles confined in porous SiO2 matrix for a robust oxygen evolution reaction

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Nano Materials Science 2022年第4期4卷 393-399页

作者： Xiaojun Zeng Haiqi Zhang Xiaofeng Zhang Qingqing Zhang Yunxia Chen Ronghai Yu Martin Moskovits School of Materials Science and Engineering Jingdezhen Ceramic UniversityJingdezhen333403China Guangdong Academy of Science Guangdong Institute of New MaterialsNational Engineering Laboratory for Modern Materials Surface Engineering TechnologyThe Key Lab of Guangdong for Modern Surface Engineering TechnologyGuangzhou510650China School of Materials Science and Engineering Beihang UniversityBeijing100191China Department of Chemistry and Biochemistry University of California Santa BarbaraSanta BarbaraCA93106United States

Rational design of electrocatalysts is important for a sustainable oxygen evolution reaction(OER).It is still a huge challenge to engineer active sites in multi-sizes and multi-components ***,a series of CoxP nanoparticles(NPs)confined in an SiO2matrix(SiO2/CoxP)is designed and synthesized as OER *** phosphorization of the hydrolyzed Co-phyllosilicate promotes the formation of ultrasmall and small Co2P and *** are firmly confined in the *** coupling of multi-size and multi-component CoxP catalysts can regulate reaction kinetics and electron transfer ability,enrich the active sites,and eventually promote the intrinsic OER *** SiO2matrix provides abundant porous structure and oxygen vacancies,and these facilitate the exposure of active sites and improve *** of the synergy and interplay of multisized/component CoxP NPs and the porous SiO2matrix,the unique SiO2/CoxP heterostructure exhibits low overpotential(293 m V@10 mA cm-2),and robust stability(decay 12 mV after 5000 CV cycles,97.4%of initial current after 100 h chronoamperometric)for the OER process,exceeding many advanced metal phosphide *** work provides a novel tactic to design low-cost,simple,and highly efficient OER electrocatalysts.

关键词： multi-size multi-component Phyllosilicate SiO2/CoxP heterostructure OER

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一种多介质流体计算的三维非守恒型差分格式

高等学校计算数学学报 2005年第2期27卷 108-115页

作者：陈龙伟宁建国庙延钢北京 100081 北京理工大学爆炸灾害防预与控制国家重点实验室昆明 650221 昆明理工大学矿业工程博士后流动站昆明理工大学矿业工程博士后流动站昆明 650093 云南财贸学院计算机科学系

1引言守恒型差分格式用于多介质流体数值计算往往不能得到理想的结果,从双介质Rde mann问题数值结果可以看出,压力、速度在两种介质界面附近出现了非物理振荡.这不是由高精度格式引起的,一阶格式也有同样的现象.著名的Godunov、Roe、Os... 详细信息

1引言守恒型差分格式用于多介质流体数值计算往往不能得到理想的结果,从双介质Rde mann问题数值结果可以看出,压力、速度在两种介质界面附近出现了非物理振荡.这不是由高精度格式引起的,一阶格式也有同样的现象.著名的Godunov、Roe、Osher等格式都会出现此问题.Harten的TVD格式也发现同样的问题.许多学者分析了出现非物

关键词： 3D-dimension non-conservative multi-component difference numerical simulation.

Chemical synthesis of magnetic nanocrystals:Recent progress

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Chinese Physics B 2013年第10期22卷 13-31页

作者：刘飞朱静菡侯仰龙高松 Department of Materials Science and Engineering College of EngineeringPeking University College of Chemistry and Molecular Engineering Peking University

Colloidal chemical synthesis of various types of magnetic nanocrystals is discussed with regard to recent discoveries. We first outline the chemical preparation of single-component magnetic nanocrystals with controlled size, shape, and uniformity based on several solution-phase methods, especially thermal decomposition and/or reduction method. Then we discuss the synthetic strategies of multi-component nanocrystals incorporating at least one magnetic component by manipulating heterogeneous nucleation and growth process. Toward the end, approaches for preparing hollow/porous magnetic nanocrystals are highlighted. We believe that the summarized chemical synthesis will pave the way for the future development of extraordinary magnetic nanocrystals.

关键词： magnetic nanocrystals chemical synthesis single-component multi-component hollow/porous

Chlorinated polymer solar cells simultaneously enhanced by fullerene and non-fullerene ternary strategies

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Journal of Energy Chemistry 2021年第3期30卷 620-625页

作者： Longzhu Liu Pengjie Chao Daize Mo Feng He School of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbin 150001HeilongjiangChina Shenzhen Grubbs Institute and Department of Chemistry Southern University of Science and TechnologyShenzhen 518055GuangdongChina Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and TechnologyShenzhen 518055GuangdongChina

To achieve efficient polymer solar cells(PSCs)with full utilization of the whole spectrum,the multicomponent devices are of great importance to be deeply explored,especially for their capability of one-step ***,the research about one same binary system simultaneously derivated various multi-component PSC is still very ***,we achieved the whole constructions from one binary host to different ternary systems and even the quaternary *** ternary strategies with fullerene acceptor,PC_(71)BM,and non-fullerene acceptor,BT_(6)IC-BO-4Cl,as the third component,both boosted the device efficiencies of PBT4Cl-Bz:IT-4F binary system from about 9% to comparatively beyond 11%.Despite the comparable improvement of performance,there existed other similarities and differences in two ternary *** detail,the isotropic carrier transport of PC_(71)BM which largely elevated the fill factor(FF)in the corresponding devices,while the strong absorption of BT_(6)IC-BO-4Cl enhanced the short current density(J_(SC))*** interestingly,quaternary devices based on PBT4Cl-Bz:IT-4F:PC71 BM:BT_(6)IC-BO-4Cl could combine both advantages of fullerene and non-fullerene ternary strategies,further pumped the J_(SC) from 16.44 to the highest level of 19.66 mA cm^(-2) among all devices,eventually resulted in an optimized efficiency of 11.69%.It reveals that both fullerene and non-fullerene ternary strategies have their unique feature to elevate the device performance either by efficient isotropic carrier transport or better coverage of whole sunlight spectrum and easy tunable energy levels from organic *** key is how to integrate the two pathways in one system and provide a more competitive solution facing high-quality PSCs.

关键词： Chlorination Polymer solar cell multi-component Fullerene Non-fullerene

An Efficient One-pot Three-component Process for Synthesis of Perfluoroalkylated Quinolizines

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Chinese Journal of Chemistry 2016年第5期34卷 524-532页

作者： Dandan Shen Yanjie Xu Dong He Jing Han Jie Chen Hongmei Deng Min Shao Hui Zhang Weiguo cao Department of Chemistry Innovative Drug Research Center Shanghai University Shanghai 200444 China Laboratory for Microstructures Instrumental Analysis and Research Center of Shanghai University Shanghai 200444 China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China Key Laboratory of Synthetic Organic Chemistry of Natural Substances Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

A facile multi-component process for the synthesis of perfluoroalkylated quinolizine derivatives was achieved using various arylidenemalononitriles, pyridine, and methyl perfluoroalk-2-ynoates as starting materials. Moderate yields were obtained under mild condition. The structures of perfluoroalkylated quinolizine derivatives were char- acterized by means of IH NMR, 13C NMR, 19F NMR, IR, LRMS and HRMS. Furthermore, the reaction mechanism was proposed.

关键词： quinolizines perfluoroalkylated multi-component one-pot reaction