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Rare Metals 2024年第3期43卷 1263-1274页

作者： Yue Guo lin-Jun Qin Jing Xu xiao-Ping Jiang xiao-Yu Yue Yi Hou Hao Shi li-xi wang Qi-Tu Zhang Collage of Materials Science and Engineering Nanjing Tech UniversityNanjing211816China Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites Nanjing211816China

Optical temperature sensing based on the fluorescence intensity ratio(FIR)of red emission for lanthanide ions holds significant relevance in non-contact temperature measurement for biological *** this study,the perovskite-structured KZnF_(3)is utilized as a host material for Er^(3+)to achieve a high-purity upconversion(UC)red *** observed Stark splitting of the red emission peak provides evidence of the energy level splitting of Er^(3+).Group theory is employed to decompose the spectral branching of Er^(3+)under the point group symmetry of KZnF_(3),allowing for the derivation of Stark splitting energy levels induced by the crystal field *** optical temperature-sensing behavior of the red UC luminescence was investigated,specifically examining the FIR of the splitting sub-peaks,which exhibited an exponential relationship with *** KZnF_(3):Yb^(3+),Er^(3+)demonstrated a relative sensitivity(S_(r))of 0.00182%·K^(-1)at 298 K,highlighting its excellent response to *** vivo bio-thermometry experiments conducted on chicken breast validated the material's ability to penetrate biological tissues and showed its significant sensitivity of the FIR to *** results establish KZnF_(3):Yb^(3+),Er^(3+)as a promising material for optical thermometry in various biological applications.

关键词： KZnF_(3) Er^(3+) Upconversion luminescence Stark splitting Temperature sensing

Formation mechanism of an aluminium-based chemical conversion coating on AZ91D magnesium alloy

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International Journal of Minerals,Metallurgy and Materials 2010年第5期17卷 641-647页

作者： Wei-ping li xi-mei wang li-qun Zhu Wen li Key Laboratory of Aerospace Materials and Performance （Ministry of Education of China） School of Materials Science and EngineeringBeihang University Beijing 100083 China

An environmentally clean aluminium-based conversion coating on AZ91D magnesium alloy was studied in aluminium nitrate solutions. The morphology, composition, structure, and formation mechanism of the coating were investigated in detail using scanning electron microscopy/energy dispersion spectrometry, X-ray diffraction, transmission electron microscopy, and electrochemical corrosion tests. The results show that the conversion coating is composed of magnesium, aluminium, and oxygen, and shows an amorphous structure. In the initial stage of coating formation, the grain-like nucleus is composed of Al10O15·xH2O, （Al2O3）5.333, Al2O3, AlO（OH）, MgAl2O4, （Mg0.88Al0.12）（Al0.94Mg0.06）2O4, and （Mg0.68Al0.32）（Al0.84Mg0.16）2O4. The conversion coating formed in the 0.01 mol/L aluminium nitrate solution for 15 min can improve the corrosion resistance of the magnesium alloy greatly. The discussion reveals that the possible formation mechanism for the aluminium-based conversion coating is the reduction reaction on micro-cathodic sites due to the electrochemically heterogeneous magnesium alloy substrate.

关键词： magnesium alloys coatings aluminium nitrate corrosion resistance

A strategy to achieve efficient green-emission dual-mode luminescence of Yb^(3+),Er^(3+) doped NaBiF_(4)

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Rare Metals 2021年第8期40卷 2040-2048页

作者： Jin-Hui xie Jue wang Gui-Hua Qiu xi-Bing li Wen-Tao Huang Rui-Rong Zhang Tong lin li-xi wang Qi-Tu Zhang College of Materials Science and Engineering Nanjing Tech UniversityNanjing210009China Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites Nanjing210009China Shandong Institute of Non-metallic Material Jinan250031China

A series of hexagonal phase NaBiF_(4):x Yb^(3+),y Er^(3+) were successfully synthesized by solvothermal *** morphology,phase structure,up-conversion luminescence and down-conversion luminescence properties of Yb^(3+) and Er^(3+) doping concentration and the energy transfer mechanism were *** shows that the doping of Yb^(3+) and Er^(3+) does not cause the phase transition of NaBiF_(4),but influences its *** the NaBiF_(4):Yb^(3+),Er^(3+),Yb^(3+) can transfer energy with Er^(3+),enhancing up-conversion green *** Yb^(3+) doping concentration increasing,the up-conversion red-green ratio will increase while the down-conversion intensity of the green emission decreases and that of the red emission *** the potential application of Na BiF4:x Yb^(3+),y Er^(3+) phosphors in optical illumination,the thermal stability was carried out.

关键词： NaBiF_(4) Dual-mode luminescence Energy transfer High temperature fluorescence

Electromagnetic properties of BaZn_2Fe_(16)O_(27)/antimony-doped tin oxide composite absorbing materials by co-precipitation method

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Rare Metals 2014年第6期33卷 697-702页

作者： Jing Zhang li-xi wang xiao-Gu Huang Qi-Tu Zhang College of Materials Science and Engineering Nanjing University of Technology

W-type barium ferrite（Ba Zn2Fe16O27）/antimony-doped tin oxide（ATO） composite absorbing materials were synthesized by co-precipitation method, using Ba Zn2Fe16O27 prepared by traditional solid method and SnCl4·5H2O, SbCl3 as main raw materials. The structure and morphology of the composites were characterized using X-ray diffraction（XRD）, scanning electron microscopy（SEM）. The result shows that Ba Zn2Fe16O27/ATO composites were obtained by co-precipitation method, and ATO nano-particles were coated on the surface of Ba Zn2Fe16O27 ferrite. The complex permittivity and complex permeability of Ba Zn2Fe16O27/ATO composite absorbing materials at the frequency range from 2 to 18 GHz were analyzed by vector network analyzer. It is indicated that ATO has strong dielectric property and ferrite shows superior magnetic performance. The result shows that the complex permittivity and dielectric loss of the Ba Zn2Fe16O27/ATO composite absorbing materials are higher than the pure ferrite, and the complex permeability and magnetic loss are higher than the pure ferrite and the pure ATO. When the mole ratio of Ba Zn2Fe16O27/ATO is 1：2, the minimum reflection loss is about-31.14 d B at 12.4 GHz, moreover, the absorption bandwidth reaches 9.6 GHz when RL is-10 d B in the measured frequency range of Ku-band.

关键词： Ferrite ATO Composite Electromagnetic properties

Effects of body-resistance strengthening and tumor-suppressing granules on immune adhesion function of red blood cells and expression of metastasis protein CD44 in tumor cells of patients with esophageal carcinoma

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World Journal of Gastroenterology 2007年第32期13卷 4360-4364页

作者： Jian-xiong Zhao Xue-Feng li Xue-xi wang Institute of Combined Western and Chinese Traditional Medicine Lanzhou University Medical School Lanzhou 730000 Gansu Province China

AIM： To investigate the effects of Fuzheng Yiliu granules （body-resistance strengthening and tumor-suppressing granules） in patients with esophageal carcinoma. METHODS： We compared the immune adherent properties of red blood cells （RBCs）, the expression of metastasis protein CD44, and the metastasis inhibition factor nm23, in esophageal carcinoma tumor cells of patients before and after radiotherapy in the presence and absence of orally administered Fuzheng Yiliu granules. Sixty-three hospitalized patients with esophageal carcinoma were treated with standard radiotherapy and randomly divided into treatment group （n = 30） treated with both radiotherapy and Fuzheng Yiliu granules and control group （n = 33） given radiotherapy only. Blood samples and tumor tissue were obtained before and after 21 d of treatment. The rosette rates for complement receptor type 3b （C3bRR） and immune complex receptor （ICRR） on RBCs were measured by erythrocyte immunological methods. Expression of CD44 and rim23 in tumor tissue sections was determined by immunohistochemical staining with monoclonal antibodies CD44v6 ad nm23H-1, respectively. RESULTS： The positivity of RBC-C3bRR before and after 21 d of treatment increased from 7.78% ± 1.59% to 10.03% ± 2.01% in the double treatment group, while it changed only slightly from 7.18% ± 1.29% to 7.46% ± 1.12% in the radiotherapy group. The positive rate for RBC-ICRR decreased from 37.68% ± 2.51% to 22.55% ± 1.65% after the double treatment, and from 37.28% ± 2.41% to 24.69% ± 1.91% in radiotherapy group at the same time points. The difference in erythrocyte immune adherent function between the two groups was significant （P 〈 0.01, t-test）. The CD44^± - cases were reduced from 21 （70.00%） to 12 （40.00%） after treatment with Fuzheng Yiliu granules, whereas the CD44^± -cases （69.70%） in the radiotherapy group remained unchanged. The difference between the treatment （40.00%） and control （69.70%） groups was significant （P 〈 0.05）. Although the nm23^±

关键词： Fuzheng Yiliu granule RBC immune function CD44 nm23 Esophageal carcinoma Metastasis protein CD44 controlled clinical trial

Preparation, morphology and luminescence properties of Gd_2O_2S:Tb with different Gd_2O_3 raw materials

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Rare Metals 2019年第3期38卷 221-226页

作者： Yu-Jie Ding Peng-De Han li-xi wang Qi-Tu Zhang College of Materials Science and Engineering Nanjing Tech University School of Materials Engineering Yancheng Institute of Technology

The sulfide fusion method was used to synthesize Gd_2 O_2 S:Tb phosphors using commercial Gd_2 O_3 and freshly prepared Gd_2 O_3, respectively. The freshly prepared Gd_2 O_3 was synthesized from Gd_2 O(GO_3)_2·H_2 O precursor prepared by homogeneous precipitation *** structure and morphology of the composites were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM) and energy dispersive spectroscopy(EDS). The result shows that the Gd_2 O_2 S:Tb phosphor prepared by commercial Gd2 O3(GOST-A) presents agglomerated particles with average particle size of2.1 μm; however, Gd_2 O_2 S:Tb produced from as-prepared Gd_2 O_3(GOST-B) tends to form regular hexagon particles with the average particle size of 1 μm. Furthermore, Gd3+and Tb3+ contents in GOST-B are higher than that in GOST-A. In addition, fluorescent properties were analyzed by fluorescent spectrophotometer. It is indicated that similar excitation and emission spectra can be obtained from the two phosphors, but the luminescence intensity of GOST-B is higher than that of GOST-A.

关键词： Precursor Phosphor Luminescence Homogeneous precipitation Sulfide fusion

Co-luminescence properties of terbium ions–benzoic acid–phen complexes doped with europium ions

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Rare Metals 2013年第6期32卷 599-604页

作者： Jing Zhang li-xi wang Le Zhang Yan Chen Qi-Tu Zhang College of Materials Science and Engineering Nanjing University of Technology

Series of complexes Eux Tb1-x(BA)3phen(0.01 B x B 0.50)were synthesized by co-precipitation method,BA was used as the carboxylic acid ligand and 1,10-phenanthroline was used as the electrically neutral *** samples were characterized by means of X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR),thermal gravimetric analyses and differential scanning calorimetry(TG–DSC),ultraviolet and visible spectrophotometer absorption spectra,and photoluminescence spectra to study the structure,the energy absorption,the thermal,and luminescent properties of the rare earth *** results show that the series rare earth organic complexes are well crystallized and show high thermal *** luminescent intensity of europium ion in the complexes increases as terbium ion transfers the absorbed energy to europium ion in the *** emission of terbium ion at 545 nm is not quenched by europium ion but increases with the content of europium ion *** the x value is 0.01,the fluorescence intensity reaches the maximum as well as the emission intensity of terbium ions at 545 nm and europium ions at614 nm are almost *** realizes the co-luminescence phenomenon of terbium ion and europium *** series rare earth organic complexes with different colors can be obtained by adjusting the ratio of terbium ion and europium ion.

关键词： Complexes Photoluminescence Rare earth Luminescent intensity Co-luminescence

Synthesis and luminescence of ultrasmall CsPbBr_(3) nanocrystals and CsPbBr_(3)/Cs_(4)PbBr_(6) composites by one-pot method

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Rare Metals 2022年第4期41卷 1230-1238页

作者： xi-Bing li Wen-Tao Huang Rui-Rong Zhang Yue Guo Hui-Jie Yang xiao-Yue He Ming-Xun Yu li-xi wang Qi-Tu Zhang College of Materials Science and Engineering Nanjing Tech UniversityNanjing 210009China Jiangsu Collaborative Innovation Center for Advanced Inorganic Function Composites Nanjing 210009China Institute of Non-Metallic Materials Ji'nan 250031China College of 2011 Nanjing Tech UniversityNanjing 210009China

All-inorganic perovskites CsPbX_(3)(X=Cl,Br,I)have attracted worldwide interest due to their excellent lumi-nescent ***,Cs_(4)PbBr_(6) have been studied because they can enhance the luminescent efficiency and stability of CsPbBr_(3).Herein,we introduced a microfluidic method based on room-temperature supersat-urated recrystallization to synthesize blue-emitting CsPbBr_(3)nanocrystals(NCs)and green-emitting CsPbBr_(3)/Cs_(4)PbBr_(6)*** ultrasmall CsPbBr_(3)NCs emitted at a deep blue wavelength of 461 nm with the full width at half maximum(FWHM)of 15 *** electron microscopy(TEM)results demonstrated that ultrasmall CsPbBr_(3)NCs with the average particle size of 3.8 nm were synthesized and the CsPbBr_(3)NCs were crystallized as monoclinic structure.

关键词： composites (3) method

Preparation and electromagnetic properties of nanosized Co_(0.5)Zn_(0.5)Fe_(2)O_(4) ferrite

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Rare Metals 2022年第9期41卷 3228-3232页

作者： Yi-Wei liu Jing Zhang Lu-Shun Gu li-xi wang Qi-Tu Zhang College of Materials Science and Engineering Nanjing Tech UniversityNanjing210009China

Nanosized Co_(0.5)Zn_(0.5)Fe_(2)O_(4) ferrite was prepared by chemical co-precipitation *** samples were characterized by X-ray diffraction(XRD),field-emission transmission electron microscopy(FETEM),vibrating sample magnetometer(VSM)and network *** analysis indicates that the diameter of as-prepared powder is about 20-30 *** saturation magnetization of nanosized Co_(0.5)Zn_(0.5)Fe_(2)O_(4) ferrite is 74.01 mA·m^(2)·g^(−1).The complex permittivity and complex permeability of the Co-Zn ferrite were measured by vector network analyzer in the frequency range of 2.0-18.0 GHz,and the reflection loss(RL)was investigated according to the wave transmission *** results show that the maximum reflection loss reaches−13.7 dB at 6.8 GHz and the bandwidth of reflection loss less than−10 dB reaches 3.8 *** as-prepared nanosized Co_(0.5)Zn_(0.5)Fe_(2)O_(4) ferrite can be potentially used as an excellent microwave absorber in the C-band.

关键词： Nanosized Co-Zn ferrite Chemical co-precipitation method Electromagnetic properties Reflection loss

Predication of Selective Ring-opening Hydrogenolysis for Furfuryl Alcohol to Produce Pentanediol over Dual-atom Catalysts

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Chemical Research in Chinese Universities 2024年第1期40卷 55-63页

作者： wang Tingting wang Jia xi Yongjie HU Bin li Fuwei State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China

Selective activation of C-O bond is of fundamental importance in the precise conversion of oxygenates into value-added compounds in an atom-economic and sustainable manner, and meanwhile, the structurally well-defined dual-atoms catalysts (DACs) have been scarcely investigated in this field. In this study, a series of transition metal DACs anchored on nitrogen-doped graphene (TM2/NC, TM=Pt, Ir, Rh, Pd, Ru, Co, Ni and Cu) was constructed to make a comprehensive investigation of their selectivity in the hydrogenative transformation of furfuryl alcohol (FAL), an important biomass platform molecule, to 1,2-pentanediol (1,2-PeD) via selective cleavage of furanic C5-O bond, by density functional theory (DFT) calculations and microkinetic modeling. We found that Ir2/NC demonstrated a high selectivity for the cleavage of furanic C5-O bond to produce 1,2-PeD, while the production of THFAL or 1,5-pentanediol (1,5-PeD) on other TM2/NC catalysts are more favorable. Furthermore, we found that the selective C-O bond cleavage of FAL furan ring is affected by the orbital overlap between the d-orbitals of the anchored metal atoms and the p-orbitals of the adsorbed C atom in FAL, suggesting that the selectivity of the C-O bond cleavage is inextricably related with the electronic property of the anchored metals.

关键词： Furfuryl alcohol Hydrogenation Dual-atom catalyst Density functional theory(DFT)calculation