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Depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 335-345页

作者： feng zhang chenyang zhang Linlin Wu Wei Sun Hongliang zhang Jianhua chen yong Pei Songjiang Li Engineering Research Center of Ministry of Education for Carbon Emission Reduction in Metal Resource Exploitation and Utilization Hunan International Joint Research Center for Efficient and Clean Utilization of Critical Metal Mineral ResourcesSchool of Minerals Processing and BioengineeringCentral South UniversityChangsha 410083China State Key Laboratory of Mineral Processing Beijing General Research Institute of Mining&MetallurgyBeijing 100160China Hunan Provincial Key Laboratory of Micro&Nano Materials Interfaces Science College of Chemistry and Chemical EngineeringCentral South UniversityChangsha 410083China School of Resources Environment and MaterialsGuangxi UniversityNanning 530004China Department of Chemistry Xiangtan UniversityXiangtan 411105China China Railway Resource Group Co.Ltd Beijing 102300China

The depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite still lacked in-depth ***,the depression mechanism of sulfite ions on sphalerite and Pb^(2+)activated sphalerite in the flotation separation of galena from sphalerite was further systematically investigated with experiments and density functional theory(DFT)*** X-ray photoelectric spectroscopy(XPS)results,DFT calculation results,and frontier molecular orbital analysis indicated that sulfite ions were difficult to be adsorbed on sphalerite surface,suggesting that sulfite ions achieved depression effects on sphalerite through other non-adsorption ***,the oxygen content in the surface of sphalerite treated with sulfite ions in creased,which enhanced the hydrophilicity of the sphalerite and further increased the difference in hydrophilicity between sphalerite and ***,sulfite ions were chelated with lead ions to form PbSO_(3)in *** hydrophilic PbSO_(3)was more easily adsorbed on sphalerite than *** interaction between sulfite ions and lead ions could effectively inhibit the activation of *** addition the UV spectrum showed that after adding sulfite ions,the peak of perxanthate in the sphalerite treated xanthate solution was significantly stronger than that in the galena with xanthate solution,indicating that xanthate interacted more readily with sulfite ions and oxygen mo lecules within the sphalerite system,leading to the formation of ***,sulfite ions hardly depressed the flotation of ga lena and could promote the flotation of galena to some *** study deepened the understanding of the depression mechanism o sulfite ions on sphalerite and Pb^(2+)activated sphalerite.

关键词： sphalerite galena sulfite ion density functional theory depression mechanism

Catalytic atroposelective synthesis of indolyl quinazolinones bearing N-N/C-C diaxes

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Science China Chemistry 2025年

作者： Ning-Yi Wang Shuo Gao Zhu-di Shu Bei-Bei cheng chun Ma Yu-chen zhang feng Shi Research Center of Chiral Functional heterocycles School of Chemistry and Materials Science Jiangsu Normal University School of Petrochemical Engineering Changzhou University School of Chemistry and Chemical Engineering Henan Normal University

The first catalytic atroposelective synthesis of indole derivatives bearing N-N/C-C diaxes has been established by the strategy of de novo ring formation. By this strategy, various indolyl quinazolinones bearing vicinal N-N/C-C diaxes were synthesized in high yields with overall good diastereoselectivities and excellent enantioselectivities via chiral phosphoric acid-catalyzed onepot asymmetric formal (5+1) cycloaddition/oxidation reaction. Moreover, such indolyl quinazolinones bearing vicinal N-N/CC diaxes have good configurational stability and could be converted into new chiral ligands with applications in asymmetric catalysis. Therefore, this work not only offered a new member for the family of diaxial atropisomers, but also provided a powerful strategy for catalytic asymmetric synthesis of atropisomers bearing N-N/C-C diaxes.

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Recent progress on photoactive nonprecious transition-metal complexes

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Science China Chemistry 2025年第1期 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.

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Core engineering of paired core-shell silver nanoclusters

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Science China Chemistry 2021年第12期64卷 2118-2124页

作者： Shan-Shan zhang Rui-chen Liu xiao-chen zhang Lei feng Qing-Wang Xue zhi-yong Gao chen-Ho Tung di Sun Key Lab of Colloid and Interface Chemistry Ministry of EducationSchool of Chemistry and Chemical EngineeringState Key Laboratory of Crystal MaterialsShandong UniversityJinan250100China School of Chemistry and Chemical Engineering Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine ChemicalsKey Laboratory of Green Chemical Media and ReactionsMinistry of EducationHenan Normal UniversityXinxiang453007China Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology School of Chemistry and Chemical EngineeringLiaocheng UniversityLiaocheng252000China

Unlike the facile modulation of surface structure through protecting ligands,the core shielded by outer shell of silver nanoclusters is still hard to be *** effects may seep into the incipient growth of silver ***,the comparable cases to validate such hypothesis are currently ***,we shed light on two core-shell silver nanoclusters,Ag_(7)S_(6)@Ag_(48)(SD/Ag55b,SD=Sundi)and Ag_(6)S_(6)@Ag_(48)(SD/Ag54b),differing in only one silver atom in the core which varies from a pentagon-bipyramidal Ag_(7)to an octahedral Ag_(6)while keeping the Ag_(48)shielding shell almost the *** no direct bonding between alkynes and silver core is observed in them,we propose that the ligand effect still exerts profound influences on the size and geometry of silver *** solution behaviours and complete ligand-exchange reaction of SD/Ag55b in CH_(2)Cl_(2)are investigated using electrospray ionization mass *** to more and stronger argentophilic interactions,SD/Ag55b exhibits room-temperature phosphorescence with a 40 nm red-shift compared to that of SD/Ag54b in CH_(2)Cl_(2).This work not only presents effective fabrication of silver nanoclusters via synergism of dithiophosphate and alkyne ligands,but also provides us a pair of comparable examples to understand substitution group effect of protecting ligand on the core structures and properties.

关键词： silver nanocluster core engineering argentophilic interactions red-shifted phosphorescence dynamic ligand exchange

Reconstruction of a muon bundle in the JUNO central detector

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Nuclear Science and Techniques 2022年第5期33卷 78-90页

作者： cheng-feng Yang yong-Bo Huang Ji-Lei Xu di-Ru Wu yong-Peng zhang Wu-Ming Luo Miao he Guo-Ming chen Si-Yuan zhang School of Physical Science and Technology Guangxi UniversityNanning 530004China Institute of High Energy Physics Beijing 100049China University of Chinese Academy of Sciences Beijing 100049China

The Jiangmen Underground Neutrino Observatory(JUNO)is a multi-purpose neutrino *** of the main goals is to determine the neutrino mass ordering by precisely measuring the energy spectrum of reactor *** the detection of reactor antineutrinos,cosmogenic backgrounds,such as^(9)Li/^(8)he and fast neutrons induced by cosmic muons,should be rejected carefully by applying muon veto cuts,which require good muon track *** a 20-kton liquid scintillator detector,the simulation shows the proportion of muon bundles(muon multiplicity≥2)to be approximately 8%in JUNO,whereas its reconstruction has been rarely discussed in previous *** study proposes an efficient algorithm for muon track reconstruction based on the charge response of a photomultiplier tube *** is the first reconstruction of muon bundles in a large-volume liquid scintillator *** addition,the algorithm shows good performance and potential for reconstruction for both a single muon and double muons(muon multiplicity=2).The spatial resolution of a single-muon reconstruction was20 cm,and the angular resolution was 0.5°.For doublemuon reconstruction,the spatial and angular resolutions could be 30 cm and 1.0°,***,this paper also discusses muon classification and the veto strategy.

关键词： JUNO Liquid scintillatordetector Muon reconstruction Muon bundle Veto strategy

Solute atom segregation to I1 stacking fault and its bounding partial dislocations in a Mg–Bi alloy

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Journal of Magnesium and Alloys 2024年第8期12卷 3135-3141页

作者： Cong he yong zhang zhiqiao Li Houwen chen Jian-feng Nie International Joint Laboratory for Light Alloys(Ministry of Education) College of Materials Science and EngineeringChongqing UniversityChongqing 400044PR China Research Center for Magnetic and Spintronic Materials National Institute for Materials ScienceTsukuba 305-0047Japan Department of Materials Science and Engineering Monash UniversityVictoria 3800Australia State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body Hunan UniversityChangsha 410082PR China

Stacking faults(SFs)and the interaction between solute atoms and SFs in a Mg–Bi alloy are investigated using aberration-corrected scanning transmission electron *** is found that abundant I_(1)SFs are generated after cold rolling and are mainly distributed inside{1012}*** aging treatment,the formation of single-layer and three-layer Bi atom segregation in the vicinity of I_(1)fault are clearly *** segregation also occurs at the 1/6bounding Frank partial dislocation *** segregation behaviors in I_(1)fault and Frank dislocations are discussed and rationalized using first-principles calculations.

关键词： Mg alloys Suzuki segregation Stacking fault Frank partial dislocation

Intensity distribution function and statistical properties of fast radio bursts

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Research in Astronomy and Astrophysics 2017年第1期17卷 71-80页

作者： Long-Biao Li yong-feng Huang zhi-Bin zhang di Li Bing Li School of Astronomy and Space Science Nanjing University Nanjing 210046 China Key Laboratory of Modern Astronomy and Astrophysics (Nanjing University) Ministry of Education Nanjing210046 China Department of Physics College of Sciences Guizhou University Guiyang 550025 China National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Key Laboratory for Radio Astronomy Chinese Academy of Sciences Nanjing 210008 China Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

Fast Radio Bursts （FRBs） are intense radio flashes from the sky that are characterized by mil- lisecond durations and Jansky-level flux densities. We carried out a statistical analysis on FRBs that have been discovered. Their mean dispersion measure, after subtracting the contribution from the interstellar medium of our Galaxy, is found to be ~ 660 pc cm-3, supporting their being from a cosmological origin. Their energy released in the radio band spans about two orders of magnitude, with a mean value of ~ 10-39 erg. More interestingly, although the study of FRBs is still in a very early phase, the published collection of FRBs enables us to derive a useful intensity distribution function. For the 16 non-repeating FRBs detected by the Parkes telescope and the Green Bank Telescope, the intensity distribution can be described as dN/dFobs = （4.1± 1.3） × 103 F-obs1.1±0.2 sky-1 d-l, where Fobs is the observed radio obs fluence in units of Jy ms. here the power-law index is significantly flatter than the expected value of 2.5 for standard candles distributed homogeneously in a flat Euclidean space. Based on this intensity distribution function, the Five-hundred-meter Aperture Spherical radio Telescope （FAST） is predicted to be able to detect about five FRBs for every 1000 h of observation time.

关键词： pulsars general - stars neutron - radio continuum general - intergalactic medium -methods statistical

Synthesis and Crystal Structure of a Novel Manganese Coordination Polymer: 2,5-Bis(4-pyridyl)-3,4-diaza-2,4-hexadiene

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Chinese Journal of Structural Chemistry 2007年第2期26卷 219-223页

作者： chen Man-Sheng DENG Yi-Fang zhang chun-Hua KUANG Dai-zhi feng yong-Lan PENG Yun-Lin Department of Chemistry and Materials Science Hen gyan g Normal University Hen gyan g 421008 China

A new manganese coordination polymer 1, [Mn（H2O）4（L）]n（ClO4）2n.2nH2O.3nL （L = 2,5-bis（4-pyridyl）-3,4-diaza-2,4-hexadiene）, has been synthesized and structurally characterized. The crystal structure was determined by single-crystal X-ray diffraction. The crystal is of monoclinic, space group Pn with a = 13.9176（8）, b = 15.4754（9）, c = 15.9670（9） A, β = 99.5010（10）°, V = 3391.8（3） ]k3, Z = 2, C56H68C12MnN16O14, Mr= 1315.10, Dc = 1.288 g/cm^3,μ = 0.344 mm^-1, F（000） = 1374, R = 0.0733 and wR = 0.2035. In the crystal the manganese atom is six-coordinated by two nitrogen atoms from 2,5-bis（4-pyridyl）-3,4-diaza-2,4-hexadiene and four oxygen atoms from water molecules, completing an octahedral geometry. The title complex exhibits a novel supramolecular layer architecture sustained by the concurrence of coordination bonds, hydrogen bonds, and π-π stacking interactions.

关键词： manganese complex Schiff bases crystal structure

Synthesis of a new 2,2':6',2''-terpyridine derivative and its coordination property

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Chinese Chemical Letters 2007年第5期18卷 530-532页

作者： yong chen xi Juan Zhao Jun feng zhang Wen Fu Fu Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100080 China Graduate University of Chinese Academy of Sciences Beijing 100039 China College of Chemistry and Chemical Engineering Yunnan Normal University Kunming 650092 China

A novel compound, （E）-4′-（4-（but-1-en-3-ynyl）phenyl）-2,2′：6′,2″-terpyridine 1 was synthesized from 4′-（4-bromomethylphenyl）-2,2P：6P,2PP-terpyridine phosphonium salt 2 and propargylaldehyde via Wittig reaction, and characterized by EI-MS and ^1H NMR as well as elemental analysis. The spectral changes of the compound in the presence of transition metal ions, such as Cu（I） or Zn（ID, are investigated.

关键词： Polypyridine ligands Synthesis Coordination