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The Main Types of the Urals Mafic-Ultramafic Complexes
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作者 SHMELEV V.R. 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期239-240,共2页
The mafic-ultramafic complexes and associated formationsare wide spread within the Ural folded belt,which is located on the boundary of the East European plate and West Siberian sedimentary basin.Two main
关键词 The Main Types of the Urals mafic-ultramafic complexes
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Olivine Compositional Mapping of Mafic-Ultramafic Complexes in Eastern Xinjiang(NW China):Implications for Cu-Ni Mineralization and Tectonic Dynamics 被引量:14
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作者 Benxun Su Kezhang Qin +4 位作者 He Sun Dongmei Tang Qinghua Xiao Pingping Liu Patrick Asamoah Sakyi 《Journal of Earth Science》 SCIE CAS CSCD 2012年第1期41-53,共13页
Early Permian mafic-ultramafic complexes in eastern Xinjiang (新疆) are mainly distributed in the Beishan (北山) area, Mid-Tianshan (天山) massif and Jueluotage (觉罗塔塔) belt. Systematic compositional mappin... Early Permian mafic-ultramafic complexes in eastern Xinjiang (新疆) are mainly distributed in the Beishan (北山) area, Mid-Tianshan (天山) massif and Jueluotage (觉罗塔塔) belt. Systematic compositional mapping of olivines from these Early Permian mafic-ultramafic complexes demonstrates that an apparently spatial distribution and heterogeneous partial melting in the mantle source exists from the Beishan area, across the Mid-Tianshan massif, to the Jueluotage belt from the south to the north. This is probably consistent with the spatial evolutional differences and tectonic features of these three belts. The decreasing degree of partial melting, as revealed by decreasing Fo contents of olivines, from south to north and from east to west reflects the southward subduction of the Paleo-Asian Ocean and the south location of the indistinct mantle plume in the Permian. Simultan ously, NiO and Fo-mapping in olivine also indicates that sulfide segregation before olivine crystallization played an important role in Ni-Cu mineralization in the mafic-ultramafic complexes. Olivines with the compositional range of Fo (77-86) and NiO (less than 0.22 wt.%) are more favorable for Ni-Cu sulfide mineralization. 展开更多
关键词 mafic-ultramafic complex oli-vine compositional mapping Ni-Cu sulfide min-eralization Beishan Mid-Tianshan massif Jue-luotage belt.
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Late Carboniferous-Early Permian Mafic-Ultramafic Complexes in Beishan,Southwestern Central Asian Orogenic Belt and Their Significance 被引量:2
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作者 KANG Lei JI Wenhua +3 位作者 WANG Tao LI Wenming SUN Jiming 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2019年第S01期113-115,共3页
Numeral Permian mafic-ultramafic complexes occur in the Beishan terrane atthe northeastern margin of the Tarim craton,southwestern Central Asian Orogenic Belt,including the Pobei,Cantoushan,Bijiashan,Hongshishan,Xuanw... Numeral Permian mafic-ultramafic complexes occur in the Beishan terrane atthe northeastern margin of the Tarim craton,southwestern Central Asian Orogenic Belt,including the Pobei,Cantoushan,Bijiashan,Hongshishan,Xuanwoling,Zhongposhan and Luodong etc.,intrusions(Qin et al.,2011;Zhang et al.,2017;Xue et al.,2018).These Beishan mafic-ultramafic complexes are composed of peridotite,pyroxenite. 展开更多
关键词 LATE Carboniferous-Early PERMIAN mafic-ultramafic complexes Beishan TARIM Large IGNEOUS Province
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Exsolution Lamellae in Olivine Grains of Dunite Units from Different Types of Mafic-Ultramafic Complexes 被引量:3
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作者 LIANG Zi XIAO yan +4 位作者 Joyashish THAKURTA SU Benxun CHEN Chen BAI Yang Patrick A. SAKYI 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第2期586-599,共14页
Exsolution microstructures in olivine grains from dunite units in a few selected tectonic environments are reported here. They include lamellae of clinopyroxene and clinopyroxene-magnetite intergrowth in the Gaositai ... Exsolution microstructures in olivine grains from dunite units in a few selected tectonic environments are reported here. They include lamellae of clinopyroxene and clinopyroxene-magnetite intergrowth in the Gaositai and Yellow Hill Alaskan-type complexes, clinopyroxene-magnetite intergrowth in the Klzildag ophiolite, and chromite lamellae in the Hongshishan mafic-ultramafic intrusive complex. These lamellae commonly occur as needle- or rod-like features and are oriented in olivine grains. The host olivine grains have Fo contents of 92.5-92.6 in the Gaositai complex, 86.5-90.1 in the Yellow Hill complex, 93.2-93.4 in the Klzlldag ophiolite and 86.9-88.3 in the Hongshishan complex. Clinopyroxene in the rod-like intergrowth exsolved in olivine grains in the Gaositai and Yellow Hill is diopside with similar major element compositions of CaO (23.6-24.3wt%), SiO2 (52.2-54.0wt%), A1203 (0.67-2.15wt%), Cr203 (0.10-0.42wt%) and Na20 (0.14-0.26wt%). It falls into the compositional field of hydrothermal clinopyroxene and its origin is thus probably related to reaction between dunite and fluids. The enrichment of the fluids in Ca2+, Fe3+, Cr3+ and Na+, resulted in elevated concentrations of these cations in olivine solid solutions via the reaction. With decreasing temperature, the olivine solid solutions altered to an intergrowth of magnetite and clinopyroxene. The Fe3+ and Cr3+ preferentially partitioned into magnetite, while Ca2+ and Na+ entered clinopyroxene. Since the studied Alaskan-type complexes and ophiolite formed in a subduction environment, the fluids were probably released from the subducted slab. In contrast, the exsolved chromite in olivine grains from the Hongshishan complex that formed in post-orogenic extension setting can be related to olivine equilibrated with Cr-bearing liquid. Similarly, these lamellae have all been observed in serpentine surrounding olivine grains, indicating genetic relations with serpentinization. 展开更多
关键词 OLIVINE DUNITE clinopyroxcne lamella intergrowth of clinopyroxenc and magnetite maficultramafic complex
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Geology and Genesis of the Mafic-Ultramafic Complexes in the Huangshan-Jingerquan (HJ) Belt, East Xinjiang 被引量:8
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作者 顾连兴 诸建林 +4 位作者 郭继春 廖静娟 严正富 杨浩 王金珠 《Chinese Journal Of Geochemistry》 EI CAS 1995年第2期97-116,共20页
More than twenty mafic-ultramafic complexes. which host several medium-or large-sized Cu-Ni deposits, occur along the Huangshan-Jingerquan (HJ ) belt in EastXinjiang. Rock types in these complexes are predominated by ... More than twenty mafic-ultramafic complexes. which host several medium-or large-sized Cu-Ni deposits, occur along the Huangshan-Jingerquan (HJ ) belt in EastXinjiang. Rock types in these complexes are predominated by peridotite, pyroxene peri-dotite, olivine pyroxenite, gabbronorite, orthopyroxene gabbro, troctolite, gabbro anddiorite. The ultramafic rocks are relatively Fe-euriched and are characterised by an as-semblage of olivine + orthopyroxene + clinopyroxene + hornblend ±plagioclase withoutobvious metamorphic textures. Chemically these complexes are relatively Fe-enrichedand show a tholeiitic trend of evolution. The complexes in this belt are intruded underthe extensional environment in a Mid-Carboniferous back-arc basin. They call be consid-ered as a new type of mafic-ultramafic complexes in orogenic belts, as designated by thename of the East-Xinjiang-type complexes. 展开更多
关键词 地质学 铁镁质超基性岩 橄榄岩 辉岩 新疆
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Tectonic Setting of the Cu-Ni Sulfide-Bearing Mafic-Ultramafic Complexes in Northern Jilin Province, NE China
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作者 Dacheng Jia Shen Liu +6 位作者 Hong Zhong Guangying Feng Youqiang Qi Wen Gao Xiao Zhang Tao Jiang Yongxin Mao 《International Journal of Geosciences》 2013年第2期317-328,共12页
There are series of Cu-Ni sulfide-bearing mafic-ultramafic intrusions widespread in north JilinProvince,Northeastern China. The intrusions formed in Xing’an-Mongolian Orogenic Belt near to the northeastern margin of ... There are series of Cu-Ni sulfide-bearing mafic-ultramafic intrusions widespread in north JilinProvince,Northeastern China. The intrusions formed in Xing’an-Mongolian Orogenic Belt near to the northeastern margin of North China Craton. The complexes were formed in almost same period according to the zircon U-Pb dating reported recently, which means that the complexes were formed in same tectonic period and belong to one tectonic magmatic event. The rock assemblages are different from the ophiolite type and Yidun type in orogenic belt. The mafic-ultramafic complexes formed in the range from 217 Ma to 232 Ma coeval with A-type granites in the area, which formed bimodal igneous rock assemblage. According to the regional angular unconformities, there were existed the orogenies of Caledonian, Hercynian, Early Indosinian, Late Indosinian and Yanshanian. The Early Indosinian coeval with orogenic I-type granites and sanukitie that suggesting the lithosphere thickening in the extrusion tectonic setting of orogenic processes, however the Late Indosinian coeval with bimodal igneous rock assemblage that suggesting the lithosphere thinning in the extension tectonic setting of post-orogenic processes in the Xing’an-Mongolian Orogenic Belt. Chemical composition of the mafic-ultramafic rocks has the characteristics of high-Mg and low-K tholeiites related with inter-continental post-orogenic tectonic setting. The trace elements indicate their formed in conditions of continental extension belt or initial rift and has the characteristics of revolution from oceanic island arc, volcanic arc of continental margin to continental extended belt. The low initial Sr isotopic ratios and positive εNd(t) values suggest that the initial magma of the complexes come from the parting melting of depleted lithospheric mantle. The depleted ithospheric mantle was new formed supported by zircon Hf isotope in Hongqiling complex. The depleted lithospheric mantle may be caused by the asthenosheric mantle upwelling and underplating in the tectonic setting of extension during the Late Indosinian post-orogenic processes. 展开更多
关键词 mafic-ultramafic INTRUSIONS TECTONIC Setting POST-OROGENIC Processes LITHOSPHERIC Extension
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SHRIMP zircon U-Pb ages of Kalatongke No.1 and Huangshandong Cu-Ni-bearing mafic-ultramafic complexes,North Xinjiang,and geological implications 被引量:110
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作者 HANBaofu JIJianqing +2 位作者 SONGBiao CHENLihui LIZonghuai 《Chinese Science Bulletin》 SCIE EI CAS 2004年第22期2424-2429,共6页
The SHRIMP zircon U-Pb dating was carried out and yielded 287±5 Ma (MSWD = 0.34) and 274±3 Ma (MSWD = 1.35) for the Kalatongke No. 1 and Huangshan- dong Cu-Ni-bearing mafic-ultramafic complexes. These ages a... The SHRIMP zircon U-Pb dating was carried out and yielded 287±5 Ma (MSWD = 0.34) and 274±3 Ma (MSWD = 1.35) for the Kalatongke No. 1 and Huangshan- dong Cu-Ni-bearing mafic-ultramafic complexes. These ages are much more precise than pre-existing rock-mineral Rb-Sr, Sm-Nd and Re-Os isochron ages for the two complexes and constrain the timing of not only the complexes but also the magmatic Cu-Ni sulfide deposits more reliably. It is neces- sary to carefully reevaluate the previous chronological data for the complexes. The Cu-Ni-bearing mafic-ultramafic com- plexes have the ages similar to those of postcollisional A-type granites in the same area, implying that they could be related to the delamination of lithospheric mantle and upwelling and partial melting of asthenospheric mantle in postcollisional setting. Therefore, the Cu-Ni-bearing mafic-ultramafic com- plexes are a direct indicator of vertical growth of the conti- nental crustal in the Central Asian Orogenic Belt. 展开更多
关键词 新疆 地质研究 SHRIMP 锆石 U-Pb年代测定 铁镁质超碱络合物 岩浆 Cu-Ni-硫化矿床
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Lithological Discrimination of the Mafic-Ultramafic Complex, Huitongshan, Beishan, China: Using ASTER Data 被引量:11
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作者 Lei Liu Jun Zhou +2 位作者 Dong Jiang Dafang Zhuang Lamin R Mansaray 《Journal of Earth Science》 SCIE CAS CSCD 2014年第3期529-536,共8页
The Beishan area has more than seventy mafic-ultramafic complexes sparsely distributed in the area and is of a big potential in mineral resources related to mafic-ultramafic intrusions. Many mafic-ultramafic intrusion... The Beishan area has more than seventy mafic-ultramafic complexes sparsely distributed in the area and is of a big potential in mineral resources related to mafic-ultramafic intrusions. Many mafic-ultramafic intrusions which are mostly in small sizes have been omitted by previous works. This research takes Huitongshan as the study area, which is a major district for mafic-ultramafic occurrences in Beishan. Advanced spaceborne thermal emission and reflection radiometer(ASTER) data have been processed and interpreted for mapping the mafic-ultramafic complex. ASTER data were processed by different techniques that were selected based on image reflectance and laboratory emissivity spectra. The visible near-infrared(VNIR) and short wave infrared(SWIR) data were transformed using band ratios and minimum noise fraction(MNF), while the thermal infrared(TIR) data were processed using mafic index(MI) and principal components analysis(PCA). ASTER band ratios(6/8, 5/4, 2/1) in RGB image and MNF(1, 2, 4) in RGB image were powerful in distinguishing the subtle differences between the various rock units. PCA applied to all five bands of ASTER TIR imagery highlighted marked differences among the mafic rock units and was more effective than the MI in differentiating mafic-ultramafic rocks. Our results were consistent with information derived from local geological maps. Based on the remote sensing results and field inspection, eleven gabbroic intrusions and a pyroxenite occurrence were recognized for the first time. A new geologic map of the Huitongshan area was created by integrating the results of remote sensing, previous geological maps and field inspection. It is concluded that the workflow of ASTER image processing, interpretation and ground inspection has great potential for mafic-ultramafic rocks identifying and relevant mineral targeting in the sparsely vegetated arid region of northwestern China. 展开更多
关键词 mafic-ultramafic complex ASTER data band ratio minimum noise fraction mafic index principal component analysis.
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Copper complexes of anthrahydrazone bearing pyridyl side chain:Synthesis,crystal structure,anticancer activity,and DNA binding 被引量:1
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作者 HUANG Yao WU Yingshu +5 位作者 BAO Zhichun HUANG Yue TANG Shangfeng LIU Ruixue LIU Yancheng LIANG Hong 《无机化学学报》 北大核心 2025年第1期213-224,共12页
To expand the study on the structures and biological activities of the anthracyclines anticancer drugs and reduce their toxic side effects,the new anthraquinone derivatives,9‑pyridylanthrahydrazone(9‑PAH)and 9,10‑bisp... To expand the study on the structures and biological activities of the anthracyclines anticancer drugs and reduce their toxic side effects,the new anthraquinone derivatives,9‑pyridylanthrahydrazone(9‑PAH)and 9,10‑bispyridylanthrahydrazone(9,10‑PAH)were designed and synthesized.Utilizing 9‑PAH and 9,10‑PAH as promising anticancer ligands,their respective copper complexes,namely[Cu(L1)Cl_(2)]Cl(1)and{[Cu_(4)(μ_(2)‑Cl)_(3)Cl_(4)(9,10‑PAH)_(2)(DMSO)_(2)]Cl_(2)}_(n)(2),were subsequently synthesized,where the new ligand L1 is formed by coupling two 9‑PAH ligands in the coordination reaction.The chemical and crystal structures of 1 and 2 were elucidated by IR,MS,elemental analysis,and single‑crystal X‑ray diffraction.Complex 1 forms a mononuclear structure.L1 coordinates with Cu through its three N atoms,together with two Cl atoms,to form a five‑coordinated square pyramidal geometry.Complex 2 constitutes a polymeric structure,wherein each structural unit centrosymmetrically encompasses two five‑coordinated binuclear copper complexes(Cu1,Cu2)of 9,10‑PAH,with similar square pyramidal geometry.A chlorine atom(Cl_(2)),located at the symmetry center,bridges Cu1 and Cu1A to connect the two binuclear copper structures.Meanwhile,the two five‑coordinated Cu2 atoms symmetrically bridge the adjacent structural units via one coordinated Cl atom,respectively,thus forming a 1D chain‑like polymeric structure.In vitro anticancer activity assessments revealed that 1 and 2 showed significant cytotoxicity even higher than cisplatin.Specifically,the IC_(50)values of 2 against HeLa‑229 and SK‑OV‑3 cancer cell lines were determined to be(5.92±0.32)μmol·L^(-1)and(6.48±0.39)μmol·L^(-1),respectively.2 could also block the proliferation of HeLa‑229 cells in S phase and significantly induce cell apoptosis.In addition,fluorescence quenching competition experiments suggested that 2 might interact with DNA by an intercalative binding mode,offering insights into its underlying anticancer mechanism.CCDC:2388918,1;2388919,2. 展开更多
关键词 anthrahydrazone metal complex crystal structure anticancer activity cell apoptosis
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Geochemistry of an Alaskan-type mafic-ultramafic complex in Eastern Desert, Egypt:New insights and constraints on the Neoproterozoic island arc magmatism 被引量:4
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作者 Shehta E.Abdallah Shehata Ali Mohamed A.Obeid 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第3期941-955,共15页
Mikbi intrusion(MI) is a part of the Neoproterozoic Nubian Shield located along the NE-SW trending major fracture zones prevailing southern Eastern Desert of Egypt. In this study, we present for the first time detaile... Mikbi intrusion(MI) is a part of the Neoproterozoic Nubian Shield located along the NE-SW trending major fracture zones prevailing southern Eastern Desert of Egypt. In this study, we present for the first time detailed mineralogical and bulk-rock geochemical data to infer some constraints on the parental magma genesis and to understand the tectonic processes contributed to MI formation. Lithologically, it is composed of fresh peridotite, clinopyroxenite, hornblendite, anorthosite, gabbronorite, pyroxene amphibole gabbro, amphibole gabbro and diorite. All rocks have low Th/La ratios(mostly <0.2) and lack positive Zr and Th anomalies excluding significant crustal contamination. They show very low concentrations of Nb, Ta, Zr and Hf together with sub-chondritic ratios of Nb/Ta(2-15) and Zr/Hf(19-35),suggesting that their mantle source was depleted by earlier melting extraction event. The oxygen fugacity(logfO_2) estimated from diorite biotite is around the nickel-nickel oxide buffer(NNO) indicating crystallization from a relatively oxidized magma. Amphiboles in the studied mafic-ultramafic rocks indicate relative oxygen fugacity(i.e. ΔNNO; nickel-nickel oxide) of 0.28-3 and were in equilibrium mostly with 3.77-8.24 wt.% H_2 O_(melt)(i.e. water content in the melt), consistent with the typical values of subduction-related magmas. Moreover, pressure estimates(0.53-6.79 kbar) indicate polybaric crystallization and suggest that the magma chamber(s) was located at relatively shallow crustal levels. The enrichment in LILE(e.g., Cs, Ba, K and Sr) and the depletion in HFSE(e.g., Th and Nb) relative to primitive mantle are consistent with island arc signature. The olivine, pyroxene and amphibole compositions also reflect arc affinity. These inferences suggest that their primary magma was derived from partial melting of a mantle source that formerly metasomatized in a subduction zone setting. Clinopyroxene and bulkrock data are consistent with orogenic tholeiitic affinity. Consequently, the mineral and bulk-rock chemistry strongly indicate crystallization from hydrous tholeiitic magma. Moreover, their trace element patterns are subparallel indicating that the various rock types possibly result from differentiation of the same primary magma. These petrological, mineralogical and geochemical characteristics show that the MI is a typical Alaskan-type complex. 展开更多
关键词 Alaskan-type complex NEOPROTEROZOIC Arc MAGMATISM Eastern DESERT EGYPT
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A mitochondria targeting Ir(Ⅲ)complex triggers ferroptosis and autophagy for cancer therapy:A case of aggregation enhanced PDT strategy for metal complexes 被引量:1
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作者 Panpan Wang Hongbao Fang +5 位作者 Mengmeng Wang Guandong Zhang Na Xu Yan Su Hongke Liu Zhi Su 《Chinese Chemical Letters》 2025年第1期374-380,共7页
Metal complexes hold significant promise in tumor diagnosis and treatment.However,their potential applications in photodynamic therapy(PDT)are hindered by issues such as poor photostability,low yield of reactive oxyge... Metal complexes hold significant promise in tumor diagnosis and treatment.However,their potential applications in photodynamic therapy(PDT)are hindered by issues such as poor photostability,low yield of reactive oxygen species(ROS),and aggregation-induced ROS quenching.To address these challenges,we present a molecular self-assembly strategy utilizing aggregation-induced emission(AIE)conjugates for metal complexes.As a proof of concept,we synthesized a mitochondrial-targeting cyclometalated Ir(Ⅲ)photosensitizer Ir-TPE.This approach significantly enhances the photodynamic effect while mitigating the dark toxicity associated with AIE groups.Ir-TPE readily self-assembles into nanoaggregates in aqueous solution,leading to a significant production of ROS upon light irradiation.Photoirradiated Ir-TPE triggers multiple modes of death by excessively accumulating ROS in the mitochondria,resulting in mitochondrial DNA damage.This damage can lead to ferroptosis and autophagy,two forms of cell death that are highly cytotoxic to cancer cells.The aggregation-enhanced photodynamic effect of Ir-TPE significantly enhances the production of ROS,leading to a more pronounced cytotoxic effect.In vitro and in vivo experiments demonstrate this aggregation-enhanced PDT approach achieves effective in situ tumor eradication.This study not only addresses the limitations of metal complexes in terms of low ROS production due to aggregation but also highlights the potential of this strategy for enhancing ROS production in PDT. 展开更多
关键词 Metal complex AIEgens Mitochondria targeting Enhanced photodynamic therapy Anticancer agent
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Synthesis,crystal structure,thermal decomposition mechanism,and fluorescence properties of benzoic acid and 4-hydroxy-2,2′:6′,2″-terpyridine lanthanide complexes
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作者 HAN Yahui ZHAO Jinjin +1 位作者 REN Ning ZHANG Jianjun 《无机化学学报》 北大核心 2025年第5期969-982,共14页
Two novel lanthanide complexes,[Sm_(2)(BA)_(6)(4-OH-terpy)_(2)]·2H_(2)O·2EtOH(1)and[Pr_(2)(BA)_(6)(4-OH-terpy)_(2)(H_(2)O)_(2)]·HBA·H_(2)O(2),where HBA=benzoic acid,4-OH-terpy=4-hydroxy-2,2'∶6... Two novel lanthanide complexes,[Sm_(2)(BA)_(6)(4-OH-terpy)_(2)]·2H_(2)O·2EtOH(1)and[Pr_(2)(BA)_(6)(4-OH-terpy)_(2)(H_(2)O)_(2)]·HBA·H_(2)O(2),where HBA=benzoic acid,4-OH-terpy=4-hydroxy-2,2'∶6',2″-terpyridine,were successfully synthesized using ultrasonic dissolution and the conventional solution method with two mixed ligands HBA and 4-OH-terpy.During the synthesis,4-OH-terpy was involved in the reaction as a neutral ligand,while HBA,in its deprotonated form(BA-),coordinated with the lanthanide ions as an acidic ligand.The crystal structures of these two complexes were precisely determined by single-crystal X-ray diffraction.Elemental analysis,infrared and Raman spectroscopy,and powder X-ray diffraction techniques were also employed to further explore the physicochemical properties of the two complexes.The single-crystal X-ray diffraction data indicate that,despite their structural differences,both complexes belong to the triclinic crystal system P1 space group.The central lanthanide ions have the same coordination number but exhibit different coordination environments.To comprehensively evaluate the thermal stability of these two complexes,comprehensive tests including thermogravimetric analysis,differential thermogravimetric analysis,differential scanning calorimetry,Fourier transform infrared spectroscopy,and mass spectrometry were conducted.Meanwhile,an in-depth investigation was conducted into the 3D infrared stacked images and mass spectra of the gases emitted from the complexes.In addition,studies of the fluorescence properties of complex1 showed that it exhibited fluorescence emission matching the Sm^(3+)characteristic transition. 展开更多
关键词 lanthanide complexes crystal structure THERMOCHEMISTRY fluorescence spectrum
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Arc magma evolution: Insights from magnesium and iron isotope in mafic-ultramafic rocks, Eastern Kunlun, NW China
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作者 Zhixiong Zhao Guochen Dong +1 位作者 Shan Ke Dicheng Zhu 《Geoscience Frontiers》 2025年第5期427-438,共12页
The origin of magnesium and iron isotope variations in mafic–ultramafic rocks has long been debated.In particular,a substantial lack of understanding exists regarding how the variation in the Mg and Fe isotopic compo... The origin of magnesium and iron isotope variations in mafic–ultramafic rocks has long been debated.In particular,a substantial lack of understanding exists regarding how the variation in the Mg and Fe isotopic compositions of arc magmas relates to fractional crystallization.Here,we report new Mg and Fe isotopic analyses of mafic–ultramafic rocks formed by co-genetic magmatic evolution in the Eastern Kunlun orogenic belt.The ultramafic and gabbro samples present mantle-like Mg isotopic compositions,with δ^(26)Mg values ranging from−0.279‰to−0.266‰for wehrlite,−0.266‰to−0.243‰for clinopyroxenite,and−0.284‰to−0.253‰for gabbro.In contrast,the δ^(26)Mg values of the hornblende gabbro samples are significantly higher(−0.195‰to−0.176‰).These rocks have similar heavy Fe isotopic compositions,withδ56Fe values ranging from 0.020‰to 0.157‰.The high δ^(26)Mg values observed in the hornblende gabbro are interpreted as indicating a maximum of 6%olivine fractionation,whereas the slightly high δ^(26)Mg values in the clinopyroxenite are ascribed to the accumulation of titanomagnetite.The Fe isotopic signatures of these rocks are inherited from magmatic sources.A comparison of the studied rocks with other mafic-ultramafic rocks implies that partial melting of mantle wedges induced by metasomatism of marine sediment-derived melts could generate“dry”arc magmatism,which would necessitate a more comprehensive and detailed analysis in further investigations. 展开更多
关键词 Mg-Fe isotopes mafic-ultramafic rocks Fractionation crystallization East Kunlun
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Ligand substitution of diiron hexacarbonyl complex with aminodiphosphine to prepare diiron aminophosphine complexes relevant to[FeFe]-hydrogenases
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作者 LIU Xufeng WANG Shaojie ZHAO Peihua 《无机化学学报》 北大核心 2025年第9期1851-1858,共8页
To extend a new family of aminophosphine-coordinated[FeFe]-hydrogenase mimics for catalytic hydro-gen(H_(2))evolution,we carried out the ligand substitutions of diiron hexacarbonyl precursors[Fe_(2)(μ-X_(2)pdt)(CO)_(... To extend a new family of aminophosphine-coordinated[FeFe]-hydrogenase mimics for catalytic hydro-gen(H_(2))evolution,we carried out the ligand substitutions of diiron hexacarbonyl precursors[Fe_(2)(μ-X_(2)pdt)(CO)_(6)](X_(2)pdt=(SCH_(2))_(2)CX_(2),X=Me,H)with aminodiphosphines(Ph_(2)PCH_(2))_(2)NY(Y=(CH_(2))_(2)OH,(CH_(2))_(3)OH)to obtain two new diiron aminophosphine complexes[Fe_(2)(L1)(μ-Me_(2)pdt)(CO)_(5)](1)and[Fe_(2)(L2)(μ-H_(2)pdt)(CO)_(5)](2),where L1=3-[(diphe-nylphosphaneyl)methyl]oxazolidine,L2=3-[(diphenylphosphaneyl)methyl]-1,3-oxazinane.Moreover,the structures of 1 and 2 have been fully confirmed by elemental analysis,spectroscopic techniques,and single-crystal X-ray diffraction.Using cyclic voltammetry(CV),we investigated the electrochemical redox performance and proton reduc-tion activities of 1 and 2 in acetic acid(HOAc).The CV study indicates that diiron aminophosphine complexes 1 and 2 can be considered to be hydrogenase-inspired diiron molecular electrocatalysts for the reduction of protons into H 2 generation in the presence of HOAc.CCDC:2443967,1;2443969,2. 展开更多
关键词 [FeFe]-hydrogenases diiron model complexes aminophosphine ligand STRUCTURE electrochemical performance
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Crystal structure and antibacterial activity of two Gd_(2)complexes based on polydentate Schiff-base ligands
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作者 ZHANG Yingyue KANG Liuqing +2 位作者 YANG Yating GUAN Xiaofen WANG Wenmin 《无机化学学报》 北大核心 2025年第9期1867-1877,共11页
Two Gd_(2)complexes,namely[Gd_(2)(dbm)_(2)(HL_(1))_(2)(CH_(3)OH)_(2)]·4CH_(3)OH(1)and[Gd_(2)(dbm)_(2)(L_(2))_(2)(CH_(3)OH)_(2)]·2CH_(3)OH(2),where H_(3)L_(1)=(Z)-N'-[4-(diethylamino)-2-hydroxybenzylidene... Two Gd_(2)complexes,namely[Gd_(2)(dbm)_(2)(HL_(1))_(2)(CH_(3)OH)_(2)]·4CH_(3)OH(1)and[Gd_(2)(dbm)_(2)(L_(2))_(2)(CH_(3)OH)_(2)]·2CH_(3)OH(2),where H_(3)L_(1)=(Z)-N'-[4-(diethylamino)-2-hydroxybenzylidene]-2-hydroxyacetohydrazide,H_(2)L_(2)=(E)-N'-(5-bromo-2-hydroxy-3-methoxybenzylidene)nicotinohydrazide,Hdbm=dibenzoylmethane,have been constructed by adopting the solvothermal method.Structural characterization unveils that both complexes 1 and 2 are constituted by two Gd^(3+)ions,two dbm-ions,two CH_(3)OH molecules,and two polydentate Schiff-base ligands(HL_(1)^(2-)or L_(2)^(2-)).In addition,complex 1 contains four free methanol molecules,whereas complex 2 harbors two free methanol molecules.By investigating the interactions between complexes 1 and 2 and four types of bacteria(Bacillus subtilis,Escherichia coli,Staphylococcus aureus,Candida albicans),it was found that both complexes 1 and 2 exhibited potent antibacte-rial activities.The interaction mechanisms between the ligands H_(3)L_(1),H_(2)L_(2),complexes 1 and 2,and calf thymus DNA(CT-DNA)were studied using ultraviolet-visible spectroscopy,fluorescence titration,and cyclic voltammetry.The results demonstrated that both complexes 1 and 2 can intercalate into CT-DNA molecules,thereby inhibiting bacterial proliferation to achieve the antibacterial effects.CCDC:2401116,1;2401117,2. 展开更多
关键词 Gd_(2)complex polydentate Schiff base crystal structure DNA INTERACTION antibacterial activity
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A series of iridium(Ⅲ)complexes with fluorophenyl isoquinoline ligand and low-efficiency roll-off properties:A density functional theory study
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作者 QIN Zhengkun PAN Zicong +2 位作者 TIAN Hui ZHANG Wanyi SONG Mingxing 《无机化学学报》 北大核心 2025年第6期1235-1244,共10页
We have examined the theoretical implications of combining two main and three auxiliary ligands to form several Ir(Ⅲ)complexes featuring a transition metal as their core atom to identify some appropriate organic ligh... We have examined the theoretical implications of combining two main and three auxiliary ligands to form several Ir(Ⅲ)complexes featuring a transition metal as their core atom to identify some appropriate organic lightemitting diode(OLED)materials.By utilizing electronic structure,frontier molecular orbitals,minimum single-line absorption,triplet excited states,and emission spectral data derived from the density functional theory,the usefulness of these Ir(Ⅲ)complexes,including(piq)_(2)Ir(acac),(piq)_(2)Ir(tmd),(piq)_(2)Ir(tpip),(fpiq)_(2)Ir(acac),(fpiq)_(2)Ir(tmd),and(fpiq)_(2)Ir(tpip),in OLEDs was examined,where piq=1-phenylisoquinoline,fpiq=1-(4-fluorophenyl)isoquinoline,acac=(3Z)-4-hydroxypent-3-en-2-one,tmd=(4Z)-5-hydroxy-2,2,6,6-tetramethylhept-4-en-3-one,and tpip=tetraphenylimido-diphosphonate.These complexes all have low-efficiency roll-off properties,especially(fpiq)_(2)Ir(tpip).Some researchers have successfully synthesized complexes extremely similar to(piq)_(2)Ir(acac)through the Suzuki-Miyaura coupling reaction. 展开更多
关键词 density functional theory organic light-emitting diodes luminescent materials Ir(Ⅲ)complexes
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Cu(Ⅱ) and Cu(Ⅰ) complexes based on derivatives of imidazo[1,5-a]pyridine:Synthesis,structures,in situ metal-ligand reactions,and catalytic activity
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作者 JIA Bofei LIU Zhihao +7 位作者 GAO Zongyuan ZHOU Shuai WU Mengxiang ZHANG Qian ZHANG Xiamei CHEN Shuzhong YANG Xiaohan LI Yahong 《无机化学学报》 北大核心 2025年第5期1020-1036,共17页
Three efficient methods for the synthesis of a series of Cu(Ⅱ) and Cu(Ⅰ) complexes based on imidazo[1,5-a]pyridine derivatives were developed.These methods include the following:(ⅰ)Cu(Ⅱ) salts were used as metal s... Three efficient methods for the synthesis of a series of Cu(Ⅱ) and Cu(Ⅰ) complexes based on imidazo[1,5-a]pyridine derivatives were developed.These methods include the following:(ⅰ)Cu(Ⅱ) salts were used as metal sources and N,N-dimethylformamide was employed as a solvent as well as a reductant to produce Cu(Ⅰ) complexes.(ⅱ) An iodide-containing compound was utilized as a ligand and iodide source to prepare complexes.An in situ metalligand reaction occurred and an iodide-bridged copper complex was generated.(ⅲ) A series of aldehydes were added to the reaction systems to induce in situ metal-ligand reactions between the aldehydes and the imidazo[1,5-a]pyridine derivatives,producing polydentate ligand scaffolds.Eight complexes were prepared and characterized.The catalytic activities of these complexes toward the ketalization of ketones by ethylene glycol were investigated.With the exception of complex4,the remaining seven complexes all showed high catalytic activity.The lower activity of 4 may be due to the larger radius of bridging iodide ions and the shorter Cu(Ⅰ)…Cu(Ⅰ) distance.CCDC:2357696,1·2CH_(2)Cl_(2);2357697,2;2018292,3;2092192,4;2092190,5;2155557,6;2406155,7;2406156,8·EtOH. 展开更多
关键词 copper complexes imidazo[1 5‑a]pyridine in situ metal-ligand reactions ketalization reactions
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Direct identification of energy transfer mechanism in Ce^(Ⅲ)-Mn^(Ⅱ)system by constructing molecular heteronuclear complexes
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作者 Huanyu Liu Gang Yu +6 位作者 Ruoyao Guo Hao Qi Jiayin Zheng Tong Jin Zifeng Zhao Zuqiang Bian Zhiwei Liu 《Chinese Chemical Letters》 2025年第2期156-160,共5页
Sensitization of metal-centered forbidden transitions is of great significance.Solid MnII-based phosphors with d-d forbidden transition sensitized by CeIIIwith d-f allowed transition are promising light conversion mat... Sensitization of metal-centered forbidden transitions is of great significance.Solid MnII-based phosphors with d-d forbidden transition sensitized by CeIIIwith d-f allowed transition are promising light conversion materials,but the energy transfer mechanism in CeIII-MnIIis still in dispute for the uncertainty of distances between metal centers.Herein,for the first time,we explored the energy transfer mechanism in two well-designed luminescent heteronuclear complexes with clear crystal structures,i.e.,Ce-N8-Mn and Ce-N2O6-Mn(N8=1,4,7,10,13,16,21,24-octaazabicyclo[8.8.8]hexacosane;N2O6=4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane).Short distances between metal centers facilitate efficient energy transfer from CeIIIto MnIIin both complexes,resulting in high photoluminescence quantum yield up to unity.After systematic study of the two heteronuclear complexes as well as two reference complexes Ce(N8)Br3and Ce(N2O6)Br3,we concluded that dipole-quadrupole interaction is the dominant energy transfer mechanism in the heteronuclear complexes. 展开更多
关键词 Dipole-quadrupole interaction Förster resonance energy transfer Manganese complex Cerium complex PHOTOLUMINESCENCE
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Study on the Borylation of β-C Positions of Aryl Olefins Catalyzed by Copper Organophosphorus Complexes
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作者 Du Shunli Wang Yaya +2 位作者 Guo Jiaming Xu Xuewei Peng Xinhua 《有机化学》 北大核心 2025年第7期2435-2443,共9页
Organoboron compounds have become important intermediates for the construction of new compounds in synthetic chemistry and pharmaceutical chemistry,and it has been found that pinacol biborate(B_(2)pin_(2))as the boron... Organoboron compounds have become important intermediates for the construction of new compounds in synthetic chemistry and pharmaceutical chemistry,and it has been found that pinacol biborate(B_(2)pin_(2))as the boron source and Cu^(Ⅱ) organophosphorus complex(L)as the catalyst can effectively realize the hydrogen-reduced borylation products and dehydrohydrated borylation products of aryl olefins.The reaction regioselectivity involvingβ-C positions of aryl olefins can be controlled by regulating the ligand and additive types.The formation mechanism of the product is conducted at LCu^(Ⅰ)Bpin formed from Cu^(Ⅱ),L and B_(2)pin_(2).Subsequently the substrate aryl olefins undergo addition reaction to form the active intermediate PhCH(LCu^(Ⅰ))CH_(2)Bpin.Followed by the metathesis of the active intermediate with water to form hydrogen reduction products,the same active intermediate can be oxidized with 2,2,6,6-tetramethylpiperidoxyl(TEMPO)to form trans dehydrogenation products. 展开更多
关键词 arylenes bis(pinacolato)diboron copper organic phosphine complex hydrogenative borylation reduction boron dehydrogenation oxidation
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Large energy gap between singlet and triplet states is no longer a problem:intermediate charge transfer state boosts overall quantum yield up to 67%in Eu^(3+)complexes
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作者 Nane A.Avagyan Pavel S.Lemport +10 位作者 Trofim A.Polikovskiy Alisia V.Tsorieva Mikhail T.Metlin Ilya V.Taydakov Roman V.Zonov Konstantin A.Lyssenko Mikhail F.Vokuev Igor A.Rodin Vitaly A.Roznyatovsky Yuri A.Ustynyuk Valentine G.Nenajdenko 《Rare Metals》 2025年第6期4279-4293,共15页
New complexes of europium,gadolinium and terbium trinitrates with N,N,N’,N’-tetraalkyl substituted phenanthroline diamides were synthesized.The europium complexes were found to be highly efficient in terms of lumine... New complexes of europium,gadolinium and terbium trinitrates with N,N,N’,N’-tetraalkyl substituted phenanthroline diamides were synthesized.The europium complexes were found to be highly efficient in terms of luminescence properties(max quantum yield=67%).The significant influence of the structure of the ligands on the photophysical characteristics of their complexes was demonstrated.Thus,the incorporation of various substituents(Cl,F,O,OH)into the phenanthroline core causes significant changes in the luminescent behavior of the obtained coordination compounds.We observed significant differences in the energy gap between the excited states S_(1)and T_(1),especially in the L2H.Eu(NO_(3))_(3)and L2FOH.Eu(NO_(3))_(3)complexes,which both demonstrated high overall quantum yields(66%and 67%,respectively).Study of the diffuse reflection spectra of terbium complexes suggested the phenomenon of charge transfer,potentially ligand-to-ligand(LLCT)or intra-ligand(ILCT),rather than ligand-to-metal charge transfer(LMCT).These results highlight the complicated relationship between ligand structure,energy transfer mechanisms and quantum yield in rare earth element complexes,shedding light on ways to optimize their luminescent properties. 展开更多
关键词 PHENANTHROLINE LANTHANIDE complex LUMINESCENCE DFT X-ray
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