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Recent progress on photoactive nonprecious transition-metal complexes

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Science China Chemistry 2025年第1期68卷 46-95页

作者： Zhong-Liang Gong Hong-Jie Zhang Yan Cheng Jianxun Liu Yuhan Ai Yaqin Li Zhihui Feng Qiong Zhang Shaolong Gong Yong Chen Chang-Jiang Yao Yuan-Yuan Zhu Liang-Jin Xu Yu-Wu Zhong CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences State Key Laboratory of Structural Cemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences School of Chemistry and Chemical Engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of Technology State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical Engineering Beijing Institute of Technology College of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Wuhan University School of Chemistry and Chemical Engineering Anhui University Key Laboratory of Photochemical Conversion and Optoelectronic Materials & CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Photoactive complexes of nonprecious transition metals, mainly including those in the first-row and partially the second-row of the Periodic table of elements, have received increasing attention in view of their low cost and long-term sustainability. They are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices, artificial photosynthesis, photocatalysis, biodiagnostics, and therapeutics, etc. This review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes, including photoactive Zr, V, cr, Mo, and W complexes, Mn complexes and hybrids, Fe, Co, Ni, and Cu complexes, and Zn and Cd complexes and hybrids. A particular focus is given on the molecular design, modulation of photophysical and photochemical properties, and applications of the representative and lately-developed nonprecious metal complexes. In addition, a perspective on the future development in this field is provided at the end of this review.

关键词： photoactive metal complexes earth-abundant metals nonprecious metal complexes luminescence photochemistry

Laser assisted phase transformation of carbon-based transition metal oxide electrode for high-performance supercapacitor application

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Science China Chemistry 2025年

作者： Mingzhen Xiu Jianghong Zhang Yu Lu Xun Cao Kang Huang Siyu Zhu Bowei Zhang Yu Liang Chunwang Zhao Junsheng Wu Yizhong Huang School of Materials Science and Engineering Nanyang Technological University Energy Research institute Interdisciplinary Graduate Programme Nanyang Technological University institute of Sustainability for Chemicals Energy and Environment Agency for Science Technology and ResearchSingapore institute of advanced Materials and Technology University of Science and Technology Beijing School of Materials Science and Technology Shenyang University of Chemical Technology School of Materials Science and Hydrogen Energy Foshan University

Transitional metal oxides have a wide range of applications due to their superior *** enhanced performance of metal oxide relies on their desirable oxidation states,which is challenging to achieve and requires complex *** study demonstrates a facile strategy enabling rapid phase transformation of transition metal *** approach involves synthesis of a tetragonal Mn3O4/carbon cloth composite using the liquid plasma discharge deposition （LPDD） technique,followed by laser irradiation with the presence of ethylene glycol under an N2gas *** resulting face-centered cubic MnO/carbon cloth electrode exhibits an excellent capacitance of 1,125 F g-1at 2 A g-1,with remarkable capacitance retention of 95%after10,000 *** approach can be extended to other transition metals including Co,Cu,cr,Fe,Ni,and *** simulations reveal the significance of ethylene glycol and the underlying mechanism associated with the phase transformation of transition metal *** present study offers a powerful technique for the phase transformation of transition metal oxide which can guide the development of new electrode materials with enhanced electrochemical properties for high-performance energy storage applications.

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High-dense nanocrystalline W-based alloy prepared by hot isostatic pressing with uniform microstructure, ultrahigh hardness and good thermal stability

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Tungsten 2025年第1期7卷 120-136页

作者： Zao-Ming Wu Lin He Lin-Sen Ye Xiao-Feng Yang Jia-Jia Zhang Hong-Bo Lei institute of Materials China Academy of Engineering Physics

High-density uniform microstructure nanocrystalline W-10wt.% cr-5wt.% Y（W-10cr-5Y） alloy with an average grain size of 85 nm and a relative density of 99.8% was successfully prepared.W-cr-Y alloys with different amounts of second-phase particles were prepared by high-energy ball milling and hot isostatic pressing *** effects of composition design,ball milling parameters,and sintering parameters on the microstructure of W-cr-Y alloys were studied.A feasible technology for controlling the synthesis of high-density nanocrystalline W-based alloys has been *** microstructure analysis of nanocrystalline W-10cr-5Y alloy shows that there are two types of doping in the second phase:intergranular doping and intragranular *** "uniform distribution YOx-rich particles" effectively suppresses the grain growth of W and leads to the formation of nanocrystalline W-10cr-5Y alloy.W-10cr-5Y has an ultra-high hardness,with a Vickers hardness of 1312±12 kgf·***-temperature annealing treatment shows that W-10cr-5Y has good thermal stability at 1000 and1100℃,as demonstrated by the comparison of Vickers hardness and grain size between annealed and unannealed alloys.

关键词： Hot isostatic pressing Microstructure Nanocrystalline tungsten Thermal stability Vickers hardness

Enhancement of luminescence intensity and spectroscopic analysis of Eu^(3+) activated and Li^+ charge-compensated Bi_2O_3 nanophosphors for solid-state lighting

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Journal of Rare Earths 2019年第4期37卷 356-364页

作者： S.Ashwini S.C.Prashantha RamachANDra Naik H.Nagabhushana Department of Physics Channabasaveshwara Institute of Technology Research Center Department of Science East West Institute of Technology Department of Physics New Horizon College of Engineering CNR rao Center for advanced Materials Tumkur University

The present work reports the synthesis, characterization, photoluminescence and photocatalytic activity of Eu^(3+)(1 mol%-11 mol%) doped and Li^+(0.5 mol%-5 mol%) co-doped Bi_2 O_3 nanophosphors(NPs) by sonochemical method. The average particle size was estimated using powder X-ray diffraction(PXRD)and transmission electron microscopy(TEM) and is found to be in the range of 30-35 nm. The scanning electron microscopy(SEM) images were highly dependent on sonication time and concentration of epigallocatechin gallate(EGCG) bio-surfactant. The energy gap of doped and co-doped Bi_2 O_3 nanophosphors was estimated using Kubelka-Munk(K-M) function and is found to be in the range of2.9-3.08 eV. The effect of Li+ co-doping on luminescence of optimized Bi_2 O_3:Eu^(3+) was studied and is found about more than 3 fold enhancement of emission intensity. Judd-Ofelt parameters(Ω_2, Ω_4 and Ω_6).transition probabilities(A_T), quantum efficiency(η), luminescence lifetime(τ_(rad)), color chromaticity coordinates(CIE) and correlated color temperature(CCT) values were estimated from the emission spectra and are discussed in detail. The estimated CIE chromaticity co-ordinates are very close to the NTSC(National Television Standard Committee) standard value of red emission. The synthesized NPs show excellent photocatalytic activity of acid red-88 under UV-light irradiation, which can degrade 98.1% in60 min. The decreasing electron-hole pair recombination rate with quick electron transfer ability is predominantly ascribed to the balance between crystallite size, morphology, band gap, defects, surface area, etc. These results show a light for the use of sonochemical route of Bi_2 O_3:Eu^(3+):Li^+ in solid state display and photocatalytic applications.

关键词： Bi2O3:Eu3+:Li+ Sonochemical Photoluminescence CIE n CCT Photocatalysis Rare earths

Spectral properties and identification of aerostatic bearings

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Acta Mechanica Sinica 2011年第1期27卷 63-67页

作者： Jan Kozánek Ladislav Pust institute of Thermomechanics AS cr

Modified rotor kit Bently Nevada was used for dynamic characteristics measurements of new developed aerostatic *** model of these bearings is considered as *** was identified with the help of harmonic force excitation independently from the speed of journal *** stiffness and damping matrices were identified for different air inlet *** calculated spectral properties allow to determine the stability boundary for suitable variation of model parameters.

关键词： Aerostatic bearing · Identification · Stiffness · Damping coefficients

Comparative study of Eu^(3+)-activated LnOCl(Ln=La and Gd) phosphors and their Judd-Ofelt analysis

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Journal of Rare Earths 2015年第9期33卷 946-953页

作者： N.Dhananjaya C.Shivakumara Rohit Saraf Sukanti Behera H.Nagabhushana Department of Physics B.M.S. Institute of Technology and Management Solid State and Structural Chemistry Unit Indian Institute of Science C. N. R. rao Center for advanced Materials Tumkur University

Eu3＋-activated layered LnOCI （Ln=La and Gd） phosphors were synthesized by the conventional solid-state method at relatively low temperature （700 ℃） and shorter duration of 2 h. The structural parameters were refined by the Rietveld refinement analysis and confirmed by the high resolution transmission electron microscopy （HRTEM）. Both the compounds were crystallized in the tetragonal structure with space group P4/nmm （No. 129）. The homogeneity of the elements were ana- lyzed by TEM mapping and found to be uniformly distributed. The photoluminescence spectra revealed that the intensity of 5D0--7F2 transition （619 nm） was more intense in Eu3＋-activated GdOC1 compared to LaOC1. This was due to the property of Gd3＋ ions to act as an intermediate sublattice to facilitate the energy transfer to Eu3＋ ions. Intensity parameters and radiative properties such as transition probabilities, radiative lifetime and branching ratio were calculated using the Judd-Ofelt theory. The CIE color coordinates result revealed that the Eu3＋-activated GdOC1 （0.641, 0.354） phosphor was close to the commercial red phosphors like, Y203：Eu3＋（0.645, 0.347）, Y202S：Eu3＋（0.647, 0.343） and National Television System Committee （NTSC）（0.67, 0.33）. The results suggest that the present GdOCI：Eu3＋ compound acts as a potential candidate for red phosphor materials.

关键词： LaOC1 GdOC1 phosphors Judd-Ofelt CIE rare earths

Passive activity enhances residual control ability in patients with complete spinal cord injury

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Neural Regeneration Research 2025年第8期20卷 2337-2347页

作者： Yanqing Xiao Mingming Gao Zejia He Jia Zheng Hongming Bai Jia-Sheng rao Guiyun Song Wei Song Xiaoguang Li Beijing Key Laboratory for Biomaterials and Neural Regeneration Beijing Advanced Innovation Center for Biomedical EngineeringSchool of Biological Science and Medical EngineeringBeihang UniversityBeijingChina Department of Rehabilitation Evaluation China Rehabilitation Research CenterBeijingChina Cardiac Center Beijing Children’s HospitalCapital Medical UniversityBeijingChina The State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijingChina Department of Rehabilitation Engineering China Rehabilitation Science InstituteBeijingChina

Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury ***,because of prolonged inactivity,initial attempts to activate these muscles may not effectively engage any of the remaining neurons in the descending pathway.A previous study unexpectedly found that a brief clinical round of passive activity significantly increased volitional muscle activation,as measured by surface *** this study,we further explored the effect of passive activity on surface electromyographic signals during volitional control tasks among individuals with complete spinal cord *** patients with chronic complete thoracic spinal cord injury were *** electromyography data from eight major leg muscles were acquired and compared before and after the passive activity *** results indicated that the passive activity led to an increased number of activated volitional muscles and an increased frequency of *** the cumulative root mean square of surface electromyography amplitude for volitional control of movement showed a slight increase after passive activity,the difference was not statistically *** findings suggest that brief passive activity may enhance the ability to initiate volitional muscle activity during surface electromyography tasks and underscore the potential of passive activity for improving residual motor control among patients with motor complete spinal cord injury.

关键词： complete spinal cord injury cycle training epidural electrical stimulation motor training passive activity physiological state spinal cord circuit surface electromyography volitional control task

A study of fire propagation in coal seam with numerical simulation of heat transfer and chemical reaction rate in mining field

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International Journal of Mining Science and Technology 2019年第6期29卷 873-879页

作者： Moisés Oswaldo Bustamante Rúa Alan José Daza Aragón Pablo Bustamante Baena National University of Colombia Cr 65 # 63 20 CIMEX Minerals Institute

Spontaneous combustion of coal is a problem that affects the mining operation and generates environ-mental,economic,social and geotechnical *** phenomenon has been divided into two pro-cesses:ignition and *** propagation develops in coal seams because of a set of factors such as direction and wind speed,fracturing and *** this work,heat transfer and chemical kinetics are studied from conservation equations of energy and species,respectively,using the software COMSOL Multiphysics to simulate the propagation of fires in coal *** possible scenarios were analyzed that usually occur in the walls of the coal seams,such as fire focus and fire complete *** was found that the propagation kinetics of the fire changes depending on the temperature,the fractur-ing of rock mass and the area of fire *** temperature values lower than 300℃,there is con-sumption around 250 cm^3/h,values around 700℃,the consumption is 1500 cm^3/h,and for fires of 1200℃ have values of 3000 cm^3/*** on the speed of propagation can vary from 4 to 17cm/day,considering on the level and fracturing of the final wall of the open pit.

关键词： Spontaneous combustion of coal Open pit mines Simulation Heat transfer Chemical reaction COMSOL

Thermal-mechanical properties of short carbon fiber reinforced geopolymer matrix composites subjected to thermal load

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Journal of Central South University 2009年第6期16卷 881-886页

作者：林铁松贾德昌何培刚王美荣 institute for advanced Ceramics Harbin Institute of Technology

Short carbon fiber preform reinforced geopolymer composites containing different contents of α-Al2O3 filler （cr（a-Al2O3）/geopolymer composites） were fabricated, and the effects of heat treatment temperatures up to 1 200 ℃ on the thermal-mechanical properties were studied. The results show that the thermal shrinkage in the direction perpendicular to the lamination of the composites gradually increases with the increase of the heat treatment temperatures from room temperature （25 ℃ ） to 1000 ℃. However, the composites in the direction parallel to the lamination show an expansion behavior. Beyond 1 000℃, in the two directions the composites exhibit a larger degree of shrinkage due to the densification and crystallization. The mechanical properties of the composites show the minimum values in the temperature range from 600 to 800 ℃ as the hydration water of geopolymer matrix is lost. The addition of α-Al2O3 particle filler into the composites clearly increases the onset crystalline temperature of leucite （KAlSi2O6） from the amorphous geopolymer matrix. In addition, the addition of α-Al2O3 particles into the composites can not only help to keep volume stable at high temperatures but also effectively improve the mechanical properties of the composites subjected to thermal load to a certain extent. The main toughening mechanisms of the composites subjected to thermal load are attributed to fiber pulling-out.

关键词： short carbon fiber α-Al2O3 thermal-mechanical properties geopolymer thermal load