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Bifunctional photocatalyst for H_(2) production and high-value product synthesis

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Journal of Materials Science & Technology 2023年第11期142卷 121-123页

作者： jianjun zhang Yao Le Yong zhang School of Chemistry Chemical Engineering and BiotechnologyNanyang Technological University21 Nanyang LinkSingapore 637371Singapore College of Architecture and Materials Engineering Hubei University of EducationWuhan 430205China School of Chemistry and Chemical Engineering Hubei Polytechnic UniversityHuangshi 435003China

Recently,a bifunctional CdS/MoO_(2)/MoS_(2) photocatalyst has been reported for coupling hydrogen production and pyruvic acid ***_(2) and MoO_(2),which are synthesized in one step,facilitate the bifunctional integration of photocatalytic hydrogen evolution and pyruvic acid synthesis by accepting photogen-erated electrons and holes,*** work inspires the new idea of coupling hydrogen production with selective organic synthesis to obtain green hydrogen and high-value products.

关键词： CdS Hollow sphere Dual cocatalysts Hydrogen evolution Organic synthesis

Effects of oxygen and carbon on the magnetic properties and microstructure of Sm_2Co_(17) permanent magnets

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Rare Metals 2007年第4期26卷 299-304页

作者： TIAN jianjun zhang Shengen QU Xuanhui School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

The research on the sintered Sm2Co17 permanent magnets prepared by metal injection molding is still at the exploratory stage. Carbon and oxygen are two key factors that influence the magnetic properties. In this article, the effects of oxygen and carbon on the properties and microstructure of the magnets have been studied. The results indicate that oxygen consumes the effective Sm content of the magnets and forms Sm2O3-the non-magnetism phase, which result in the deterioration of the magnetic properties. Besides, the magnetic properties decrease in evidence with increasing carbon content. The main factor that affects the magnetic properties is the deterioration of the microstructure of the magnets. The Sm（Co, Cu）5 phase decreases, whereas the cell size increases with the increase of the carbon content. When the carbon content is above 0.43 wt.%, the Sm（Co, Cu）5 phase is not enough to form a uniform cellular microstructure. Thus the magnetic properties disappear. ZrC is detected in the magnets by XRD when the carbon content is above 0.21 wt.%. ZrC also reduces the properties of the magnets.

关键词： permanent magnets oxygen carbon magnetic properties microstructure

Research on assessment method of intrasystem and intersystem of the global navigation satellite system

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Science China(Technological Sciences) 2015年第10期58卷 1672-1681页

作者： zhang jianjun XUE Ming XIE Jun China Academy of Space Technology Qian Xuesen Laboratory of Space Technology

The global navigation satellite system(GNSS) has become an important space infrastructure. Following GPS and GLONASS, Europe and China have been building their own global navigation satellite system, respectively, GALILEO and Compass. In order to consolidate the leadership of GPS in the globe, United States is gradually upgrading the traditional GPS. Simultaneously, Russia is also intensively restoring full performance of GLONASS. With the advancement of international satellite navigation system, satellite navigation frequency resources are already in short supply, and the design and use of the navigation signals are more sophisticated and complex due to commercial, disaster relief and other reasons. Since there may be many navigation signals in the same basic bandwidth, the coexistence of multiple systems and the combined application make intersystem mutual interference become the focus research. Under this background, the satellite navigation system mutual interference evaluation system needs to be established urgently to meet and support the compatibility and interoperability of the GNSS system. In the paper, through the performance analysis of the GNSS signal acquisition, carrier tracking, data demodulation and code tracking, the equivalent carrier to noise ratio model based on spectrum isolation coefficient is established, and the theoretical system of the GNSS signal mutual interference is proposed according to the mechanism, and the mutual interference of GPS, GALILEO and Compass system is analyzed and assessed.

关键词： GNSS intrasystem interference intersystem interference equivalent carrier to noise ratio

Preparation of pH-Responsive Doxorubicin Nanocapsules by Combining High-gravity Antisolvent Precipitation with In-situ Polymerization for Intracellular Anticancer Drug Delivery

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Chemical Research in Chinese Universities 2020年第5期36卷 927-933页

作者： LIU Jie CHEN Bo zhang jianjun College of Chemical Engineering Beijing University of Chemical TechnologyBeijing 100029P.R.China State Key Laboratory of NBC Protection far Civilian Beijing 102205P.R.China

Owing to the low pH value in tumor and cancer cells,drug delivery systems based on pH-responsive polymer nanocarriers have been extensively explored for anticancer ***,we developed a pH-responsive doxonibicin(EXDX)nanocapsule(named as DNanoCapsule)prepared by combining in-situ polymerization teclinique with high-gravity antisolvent precipitation technique throngh an amphiphilic polymerized surface *** show an obvious spherical core-shell structure with a single DOX nanoparticle encapsulated in the polymer *** rate studies prove that the DNanoCapsules have robust dnig-release profiles under acidic environments due to the division of the pH-sensitive cross-linker,which triggers thecollapse of the polymer *** in vitro investigations demonstrated that the DNanoCapsules exhibited higli cellular uptake efficiency and cytotoxicity for both HeLa and MCF-7 cancer ***,this work may provide a promising strategy to design and develop various stimuli-responsive drug nanocapsules tor the treatment of cancer or other diseases.

关键词： pH-Responsive Nanocapsule In-situ polymerization High-gravity anti solvent precipitation Anticancer cheniotherapy

Synthesis, Spectroscopic, Thermochemical Properties of Lanthanide Complexes with 3,4-Diethoxybenzoic Acid and 1,10-Phenanthroline

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Chemical Research in Chinese Universities 2015年第6期31卷 1039-1045页

作者： QI Xiaoxia REN Ning zhang Dahai zhang jianjun Testing and Analysis Center Hebei Normal University Shijiazhuang 050024 P. R. China College of Chemistry & Material Science Hebei Normal University Shijiazhuang 050024 P. R. China College of Chemical Engineering & Material Handan College Handan 056005 P. R. China

Three novel lanthanide complexes [Ln（3,4-DEOBA）3phen]2[Ln=Eu（1）, Tb（2）, Dy（3）; 3,4-DEOBA=3,4- diethoxybenzoate; phen=1,10-phenanthroline] were synthesized and characterized by elemental analysis, molar con- ductance, X-ray diffraction and infrared spectrometry. The luminescence spectra＇of complexes 1 and 2 show the cha- racteristic emission of EU^3＋ ion（^5D0→7F0-3） and Tb^3＋ ion（^5D4→^7F6-3）. The thermal decomposition mechanism of the title complexes and the analysis of the evolved gases were investigated by thermogravimetry/differential scanning calorimetry-Fourier transform infrared（TG/DSC-FTIR） technology. The results indicate the complexes are thermally stable. In the thermal decomposition of the complexes, phen molecules lost firstly, and then 3,4-DEOBA ligand de- composed into H20, CO2 and other gaseous molecules. Besides, several gaseous organic fragments were also detected. The heat capacities of complexes 1--3 were measured by DSC in a temperature range of 263.15--340.15 K. Based on the fitted polynomial and thermodynamic equations, the smoothed heat capacities and thermodynamic functions of the three complexes were calculated. The study on biological activity showed that the complexes exhibited good an- tibacterial activity against Candida albicans, Staphylococcus aureus and Escherichia coll.

关键词： Lanthanide complex Thermodynamics Thermal decomposition Heat capacity 3,4-Diethoxybenzoic acid

Bifurcation from the essential spectrum for an elliptic equation with general nonlinearities

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Science China Mathematics 2023年第10期66卷 2243-2260页

作者： jianjun zhang Xuexiu Zhong Huansong Zhou College of Mathematics and Statistics Chongqing Jiaotong UniversityChongqing 400074China South China Research Center for Applied Mathematics and Interdisciplinary Studies South China Normal UniversityGuangzhou 510631China Center for Mathematical Sciences and Department of Mathematics Wuhan University of TechnologyWuhan 430070China

In this paper,based on some prior estimates,we show that the essential spectrum λ=0 is a bifurcation point for a superlinear elliptic equation with only local conditions,which generalizes a series of earlier results ... 详细信息

关键词： elliptic equation bifurcation point essential spectrum

Fuzzy norm method for evaluating random vibration of airborne platform from limited PSD data

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Chinese Journal of Aeronautics 2014年第6期27卷 1442-1450页

作者： Wang Zhongyu Wang Yanqing Wang Qian zhang jianjun School of Instrumentation Science & Opto-electronics Engineering Beihang University College of Electronic Communication and Physics Shandong University of Science and Technology Center of Quality Engineering of China Aero-Polytechnology Establishment

For random vibration of airborne platform, the accurate evaluation is a key indicator to ensure normal operation of airborne equipment in flight. However, only limited power spectral density（PSD） data can be obtained at the stage of flight test. Thus, those conventional evaluation methods cannot be employed when the distribution characteristics and priori information are unknown. In this paper, the fuzzy norm method（FNM） is proposed which combines the advantages of fuzzy theory and norm theory. The proposed method can deeply dig system information from limited data, which probability distribution is not taken into account. Firstly, the FNM is employed to evaluate variable interval and expanded uncertainty from limited PSD data, and the performance of FNM is demonstrated by confidence level, reliability and computing accuracy of expanded uncertainty. In addition, the optimal fuzzy parameters are discussed to meet the requirements of aviation standards and metrological practice. Finally, computer simulation is used to prove the adaptability of FNM. Compared with statistical methods, FNM has superiority for evaluating expanded uncertainty from limited data. The results show that the reliability of calculation and evaluation is superior to 95%.

关键词： Expanded uncertainty Fuzzy norm method Limited PSD data Random vibration Reliability Variable interval

Non-isothermal kinetics of the first-stage decomposition reaction of the complex of samarium p-methoxybenzoate with 1,10-phenanthroline

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Rare Metals 2007年第3期26卷 292-298页

作者： zhang jianjun REN Ning CHAI Xingquan WANG Yanxun Experimental Center Hebei Normal University Shijiazhuang 050016 China College of Chemistry ＆ Matedal Science Hebei Normal University Shijiazhuang 050016 China Depamnent of Chemistry Handan College Handan 056005 China Hebei Institute of Architectural and Civil Engineering Zhangjiakou 075024 China

The complex of [Sm（p-MOBA）3phen]2 （p-MOBA, p-methoxybenzoate; phen,1 10-phenanthroline） was prepared and characterized by elemental analysis, IR, and UV spectroscopy. The thermal decomposition of the [Sm（p-MOBA）sphen]2 complex and its kinetics were studied under a static air atmosphere by TG-DTG methods. The intermediate and residue for each decomposition stage were identified from the TG curve. The kinetic parameters and mecha- nisms of the first decomposition stage were obtained from the analysis of the TG-DTG curves by a new method of processing the data of thermal analysis kinetics. The lifetime equation at a mass loss of 10% was deduced as lnr= - 30.6795 ＋ 21034.56/Tby isothermal thermogravimelric analysis.

关键词： inorganic chemistry p-methoxybenzoic acid 1,10-phenanthroline samarium complex thermal decomposition non-isothermal kinetics TG-DTG

Optical properties of conductive silver-nanowire films with different nanowire lengths

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Nano Research 2017年第11期10卷 3706-3714页

作者： Xiaoming Yu Xuan Yu jianjun zhang Liqiao Chen Yunqian Long Dekun zhang Innovation Application Institute Zhejiang Ocean University Zhoushan 316004 China College of Electronic Information and Optical Engineering Nankai University Tianjin 300071 China

Transparent electrodes made of silver nanowires （Ag NWs） exhibit a higher flexibility than conventional indium tin oxide *** this reason,Ag NWs may find applications in future flexible electronic and optoelectronic ***,different optoelectronic devices have different specific requirements for Ag *** example,the optical transmittance haze is an important but rarely studied aspect of Ag NW *** this study,the optical transmittance and optical scattering of long （5-50 μm,L-NWs） and short （1-20 μm,S-NWs） Ag NW films were *** L-NWs exhibited better optical transmission than the S-NWs,whereas the S-NWs exhibited better light-scattering properties than the *** results indicate that the L-NWs are suitable for touch-screen displays,whereas the S-NWs are better suited as transparent conductive films for solar *** analyzed the scattering ratio of forward-scattered light to backscattered light for both the L-NWs and S-NWs and discovered that the mesh size affected the scattering *** longer wavelengths,a larger mesh yielded a higher backscattering ratio,whereas a smaller mesh yielded a lower backscattering *** formulated an equation for calculating the reflection haze using the total reflection （Ag NWs/glass）,R and the reflection of glass,*** reflection haze of the S-NWs and L-NWs exhibited different trends in the visible-near-infrared *** omnidirectional scattering model for the Ag NWs was used to evaluate the Ag NW scattering *** results of this study have great significance for the evaluation of the performance of Ag NWs in optoelectronic devices.

关键词： transparent electrode silver nanowires transmittance haze factor forward scattering and backscattering reflection-haze factor