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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
关键词 The Main Types of the Urals mafic-ultramafic complexes
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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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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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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 K?z?lda? 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 K?z?lda? 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 Ca O(23.6–24.3 wt%), SiO_2(52.2–54.0 wt%), Al_2O_3(0.67–2.15 wt%), Cr_2O_3(0.10–0.42 wt%) and Na_2O(0.14–0.26 wt%). 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 Ca^(2+), Fe^(3+), Cr^(3+) 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 Fe^(3+) and Cr^(3+) preferentially partitioned into magnetite, while Ca^(2+) 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 纯橄榄岩 橄榄石 建筑群 谷物 类型 单位 CR^3+ 构造环境
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Synthesis and Physico-Chemical Characterizations of Novel Hydrazone Ligands and Their Metal Complexes against Hormone-Dependent and Independent Cancers
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作者 Sommai Patitungkho Kingkaew Patitungkho 《Open Journal of Medicinal Chemistry》 2024年第1期1-12,共12页
This work deals with the synthesis and physicochemical characterizations of a new group of novel retinoidal ligands and their metal complexes. Their in vitro anti-proliferative activities have shown that ligand L1 is ... This work deals with the synthesis and physicochemical characterizations of a new group of novel retinoidal ligands and their metal complexes. Their in vitro anti-proliferative activities have shown that ligand L1 is effective against human breast cancer BT-20 and MCF-7 cell lines. At the same time, compound L2 exerts its effect on human prostate cancer PC-3 and human breast cancer MDA-MB-231 and MCF-7 cell lines respectively. The retinoid ligands exert their pleiotropic action toward retinoic acid receptors (RARs) than their metal complexes but all compounds exhibit concentration-dependent. 展开更多
关键词 Metal complexes CANCERS ANTIOXIDANT Hydrazone Retinoid Receptors
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3,6-Bis-β-Dicarbonylsubstituted Carbazoles Bearing N-Spacers and Their Eu(III) Complexes as Immunofluorescent Labelling Agents
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作者 Dmitry E. Pugachev Georgy V. Zatonsky +2 位作者 Tatyana S. Kostryukova Anna G. Shubina Nikolay V. Vasiliev 《International Journal of Organic Chemistry》 2024年第1期20-31,共12页
New reagents for immunofluorescence analysis of carbazole series containing fluorinated β-dicarbonyl fragments and carboxylic substituent groups separated by spacers of different lengths from the light-gathering carb... New reagents for immunofluorescence analysis of carbazole series containing fluorinated β-dicarbonyl fragments and carboxylic substituent groups separated by spacers of different lengths from the light-gathering carbazole scaffold have been developed. The markers in complex with Eu<sup>3+</sup> ions possess stability in the aqueous phase, intense and prolonged luminescence (τ 550 - 570 μs) with characteristic emission maxima in the region of 615 nm and excitation wavelengths in the region of 380 - 390 nm, which distinguishes them from most of the analogs used. In the study of marker conjugation with streptavidin, a reagent containing 4 - 5 europium labeling complexes based on spacer-containing carbazole tetraketone was obtained. The marker-doped silicate nanoparticles exhibit intense and long-lived luminescence in the characteristic region. 展开更多
关键词 Fluorescence Immunoassay Fluorinated β-Diketones CARBAZOLE Europium complexes STREPTAVIDIN Nanodispersions
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Catalytic Effect of Transition Metal Complexes of Triaminoguanidine on the Thermolysis of Energetic NC/DEGDN Composite
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作者 Mohammed Dourari Ahmed Fouzi Tarchoun +4 位作者 Djalal Trache Amir Abdelaziz Roufaida Tiliouine Tessnim Barkat Weiqiang Pang 《火炸药学报》 EI CAS CSCD 北大核心 2024年第3期209-219,I0003,共12页
The transition metal complexes of triaminoguanidine(TAG-M,where M=Cobalt(Co)or Iron(Fe))have been prepared.The catalytic effect of these complexes on the thermolysis of energetic composite based on nitrocellulose and ... The transition metal complexes of triaminoguanidine(TAG-M,where M=Cobalt(Co)or Iron(Fe))have been prepared.The catalytic effect of these complexes on the thermolysis of energetic composite based on nitrocellulose and diethylene glycol dinitrate,has been investigated.Extensive characterization of the resulting energetic composites was carried out using scanning electron microscopy(SEM),X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),and differential scanning calorimetry(DSC).Isoconversional kinetic analysis was performed to determine the Arrhenius parameters associated with the thermolysis of the elaborated energetic formulations.It is found that TAG-M complexes have strong catalytic effect on the thermo-kinetic decomposition of NC/DEGDN by decreasing the apparent activation energy and significantly increased the total heat release.The models that govern the decomposition processes are also studied,and it is revealed that different reaction processes are accomplished by introduction metal complexes of triaminoguanidine.Overall,this study serves as a valuable reference for future research focused on the investigation of catalytic combustion features of solid propellants. 展开更多
关键词 triaminoguanidine transition metal complexes NITROCELLULOSE diethylene glycol dinitrate catalytic effect
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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:104
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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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Olivine Compositional Mapping of Mafic-Ultramafic Complexes in Eastern Xinjiang(NW China):Implications for Cu-Ni Mineralization and Tectonic Dynamics 被引量:11
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作者 苏本勋 秦克章 +4 位作者 孙赫 唐冬梅 肖庆华 刘平平 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 dis-tributed in the Beishan(北山) area,Mid-Tianshan(天山) massif and Jueluotage(觉罗塔格) belt.Sys-tematic compositional mapping of olivine... Early Permian mafic-ultramafic complexes in eastern Xinjiang(新疆) are mainly dis-tributed in the Beishan(北山) area,Mid-Tianshan(天山) massif and Jueluotage(觉罗塔格) belt.Sys-tematic 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 fea-tures of these three belts.The decreasing degree of partial melting,as revealed by decreasing Fo con-tents 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.Simultane-ously,NiO and Fo-mapping in olivine also indicates that sulfide segregation before olivine crystalliza-tion 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 sul-fide mineralization. 展开更多
关键词 铜镍硫化物 超镁铁质 橄榄石 复合物 构造动力学 映射 成分 新疆
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Synergistic Optimization of Buried Interface by Multifunctional Organic-Inorganic Complexes for Highly Efficient Planar Perovskite Solar Cells 被引量:1
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作者 Heng Liu Zhengyu Lu +7 位作者 Weihai Zhang Hongkang Zhou Yu Xia Yueqing Shi Junwei Wang Rui Chen Haiping Xia Hsing-Lin Wang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第9期505-519,共15页
For the further improvement of the power conversion efficiency(PCE)and stability of perovskite solar cells(PSCs),the buried interface between the perovskite and the electron transport layer is crucial.However,it is ch... For the further improvement of the power conversion efficiency(PCE)and stability of perovskite solar cells(PSCs),the buried interface between the perovskite and the electron transport layer is crucial.However,it is challenging to effectively optimize this interface as it is buried beneath the perovskite film.Herein,we have designed and synthesized a series of multifunctional organic-inorganic(OI)complexes as buried interfacial material to promote electron extraction,as well as the crystal growth of the perovskite.The OI complex with BF4−group not only eliminates oxygen vacancies on the SnO_(2) surface but also balances energy level alignment between SnO_(2) and perovskite,providing a favorable environment for charge carrier extraction.Moreover,OI complex with amine(−NH_(2))functional group can regulate the crystallization of the perovskite film via interaction with PbI2,resulting in highly crystallized perovskite film with large grains and low defect density.Consequently,with rational molecular design,the PSCs with optimal OI complex buried interface layer which contains both BF4−and−NH_(2) functional groups yield a champion device efficiency of 23.69%.More importantly,the resulting unencapsulated device performs excellent ambient stability,maintaining over 90%of its initial efficiency after 2000 h storage,and excellent light stability of 91.5%remaining PCE in the maximum power point tracking measurement(under continuous 100 mW cm−2 light illumination in N2 atmosphere)after 500 h. 展开更多
关键词 Perovskite solar cells Organic Inorganic complexes Multifunctional interfacial material Buried interface layer
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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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DNA-free genome editing in grapevine using CRISPR/Cas9 ribonucleoprotein complexes followed by protoplast regeneration
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作者 Samaneh Najafi Edoardo Bertini +2 位作者 Erica D’Incà Marianna Fasoli Sara Zenoni 《Horticulture Research》 SCIE CSCD 2023年第1期183-192,共10页
CRISPR/Cas9 genome editing technology can overcome many limitations of traditional breeding,offering enormous potential for crop improvement and food production.Although the direct delivery of Cas9-single guide RNA(sg... CRISPR/Cas9 genome editing technology can overcome many limitations of traditional breeding,offering enormous potential for crop improvement and food production.Although the direct delivery of Cas9-single guide RNA(sgRNA)ribonucleoprotein(RNP)complexes to grapevine(Vitis vinifera)protoplasts has been shown before,the regeneration of edited protoplasts into whole plants has not been reported.Here,we describe an efficient approach to obtain transgene-free edited grapevine plants by the transfection and subsequent regeneration of protoplasts isolated from embryogenic callus.As proof of concept,a single-copy green f luorescent protein reporter gene(GFP)in the grapevine cultivar Thompson Seedless was targeted and knocked out by the direct delivery of RNPs to protoplasts.CRISPR/Cas9 activity,guided by two independent sgRNAs,was confirmed by the loss of GFP f luorescence.The regeneration of GFP−protoplasts into whole plants was monitored throughout development,confirming that the edited grapevine plants were comparable in morphology and growth habit to wild-type controls.We report the first highly efficient protocol for DNA-free genome editing in grapevine by the direct delivery of preassembled Cas9-sgRNA RNP complexes into protoplasts,helping to address the regulatory concerns related to genetically modified plants.This technology could encourage the application of genome editing for the genetic improvement of grapevine and other woody crop plants. 展开更多
关键词 complexes FIR EDITING
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Pathfinder-Based Simulation and Optimization of Evacuation of Large Commercial Complexes
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作者 Jiuju Liu Shuhan Li 《Journal of Building Construction and Planning Research》 2023年第2期27-35,共9页
Large commercial complexes are large in scale, complex in function, and located in densely populated areas that are prone to casualties due to unfavorable evacuation. To comprehend the safety evacuation of large comme... Large commercial complexes are large in scale, complex in function, and located in densely populated areas that are prone to casualties due to unfavorable evacuation. To comprehend the safety evacuation of large commercial complex buildings in China, investigate the safety evacuation problems encountered during the evacuation process and the evacuation optimization design strategy, the paper uses Pathfinder to build a simulation model based on literature research and study to simulate the evacuation of personnel in a large commercial complex in Dalian and explore its problems during the evacuation process. The results show that the type of personnel has an effect on the large commercial complex’s evacuation simulation results;the total number of evacuees is non-linearly correlated with the time change curve;some staircases take a long time to evacuate and have a low utilization rate. To improve evacuation efficiency, optimization suggestions for safety exits, evacuation stairs, and evacuation channels are made based on the results. 展开更多
关键词 Commercial complex Safe Evacuation SIMULATION PATHFINDER
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Synthesis and Characterisation of Cr(III) and Co(II) Schiff Base Complexes
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作者 Fatin M. Elmagbari Ahmed N. Hammouda +2 位作者 Hamdi A. M. Bennour Rashd M. EL-Ferjani Younis O. Ben Amer 《Materials Sciences and Applications》 CAS 2023年第2期53-62,共10页
Co(II) and Cr(III) metal complexes of Schiff bases were synthesized from the condensation reaction between 4-(dimethylamino)benzaldehyde and 4-amino-3-hydroxy-naphthalene-1-sulfonic acid. Their structures were investi... Co(II) and Cr(III) metal complexes of Schiff bases were synthesized from the condensation reaction between 4-(dimethylamino)benzaldehyde and 4-amino-3-hydroxy-naphthalene-1-sulfonic acid. Their structures were investigated by elemental analysis, molar conductance measurements, infrared spectroscopy, electronic spectroscopy, and 1HNMR spectroscopy. The elemental analysis data suggested a 1:1 [M:L] ratio for the complexes. The molar conductance measurements of the complexes indicate their electrolytic nature in DMSO as a solvent. The absorption bands in the electronic spectra verified an octahedral environment around the metal ions in the complexes. 展开更多
关键词 Schiff Base Ligand complexes 1HNMR Spectra
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2,4-Dinitrophenyl Ether of Polyvinyl Alcohol and Polymer Bound Anionic SIGMA Complexes
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作者 John C. Phelan Michael J. Strauss 《International Journal of Organic Chemistry》 2023年第3期87-95,共9页
A new electrophilic polymer, 2,4-dinitrophenyl ether of polyvinyl alcohol (PVA-DNP), having a degree of substitution of 0.5 was prepared from polyvinyl alcohol (PVA) and 1-fluro-2,4-dinitrobenzene (DNFB). The PVA-DNP ... A new electrophilic polymer, 2,4-dinitrophenyl ether of polyvinyl alcohol (PVA-DNP), having a degree of substitution of 0.5 was prepared from polyvinyl alcohol (PVA) and 1-fluro-2,4-dinitrobenzene (DNFB). The PVA-DNP polymer was characterized by NMR, IR, and UV-visible spectroscopy. The reaction of PVA-DNP with sodium methoxide was followed by NMR and UV-visible spectroscopy. Evidence of polymer bound spirocyclic SIGMA complex, C-1 and C-3 polymer bound DNP-methoxy SIGMA complexes and the formation and C-1 methoxy complex of 2,4-dinitroanisole was observed. 展开更多
关键词 2 4-Dinitrophenyl Ether Polyvinyl Alcohol Anionic SIGMA complex Thermal Stability Nucleophilic Aromatic Substitution
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A Theoretical Study of Tris-(o-benzoquinonediimine)-First-Row Divalent Transition Metal Complexes
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作者 Mohammad Abdul Matin Samiran Bhattacharjee Anwar Hossain 《Advances in Chemical Engineering and Science》 CAS 2023年第2期172-188,共17页
The ligand o-phenylenediamine (opda) and its oxidized form, o-benzoquinonediimine (bqdi), act as a fascinating candidate coordinating toward transition metal ions leading to the photochemical hydrogen production in ab... The ligand o-phenylenediamine (opda) and its oxidized form, o-benzoquinonediimine (bqdi), act as a fascinating candidate coordinating toward transition metal ions leading to the photochemical hydrogen production in absence of photosensitizers. Herein, we report the systematic study of the interaction between the oxidized form bqdi ligand, tris-(o-benzoquinonediimine) with divalent first-row transition metal series using DFT calculations. The lowest energy structures, bond length, binding energies, frontier molecular orbital analysis, natural bond orbitals, and global reactivity descriptor were calculated using B3LYP/6-311G(d,P) level of theory. The time dependent-DFT at the CAM-B3LYP/6-311+G(d,p) level of theory was applied to determine the electronic structures and the optical spectra. The theoretical binding trend of the divalent first-row transition metal series is decreasing as follows: Cu >Ti > V > Co > Ni > Fe > Cr > Zn >Mn. Among them, the binding potency of iron (II) by the bqdi ligand was not predominantly sturdy as compared to other first-row divalent transition metal ions. The origin of strong coordination with Fe(II) is attributed to its extra capability to induce covalent coordination of bqdi ligands. The complex exhibited two strong peaks at 370 nm and 452 nm, due to the HOMO-3 to LUMO+1 and HOMO-1 to LUMO transitions, respectively. Natural bond orbital analysis showed that the major interaction happens between the N lone pair electrons of the ligand with an anti-bonding orbital of metal ions, in which Ti showed the highest interaction energy than other metal ions. The present systemic DFT study of bqdi ligands with the first-row transition metals strongly encourages the future establishment of photochemical hydrogen production in absence of photosensitizers. 展开更多
关键词 DFT O-PHENYLENEDIAMINE o-benzoquinodiimine First-Row Divalent Transition Metals Time Dependent–DFT Coordination complexes
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Probing electronic structures of transition metal complexes using electron paramagnetic resonance spectroscopy
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作者 Shengfa Ye 《Magnetic Resonance Letters》 2023年第1期43-60,I0003,共19页
Electron paramagnetic resonance(EPR)or electron spin resonance(ESR)has been widely employed to characterize transition metal complexes.However,because of the high degree of complexity of transition metal EPR spectra,h... Electron paramagnetic resonance(EPR)or electron spin resonance(ESR)has been widely employed to characterize transition metal complexes.However,because of the high degree of complexity of transition metal EPR spectra,how to extract the underlying electronicstructure information inevitably poses a major challenge to beginners,in particular for systems with S>1/2.In fact,the physical principles of transition metal EPR have long been well-established and since 1970s a series of dedicated voluminous monographs have been published already.Not surprisingly,they are not appropriate stating points for novices to grasp a panorama of the profound theory prior to scrutinizing in-depth references.The present review aims to fill this gap to provide a perspective of transition metal EPR and unveil some peculiar subtleties thereof on the basis of our recent work. 展开更多
关键词 EPR Electronic structures Transition metal complexes Spin Hamiltonian
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Three-dimensional magnetic reconnection in complex multiple X-point configurations in an ancient solar-lunar terrestrial system
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作者 何向磊 毛傲华 +2 位作者 孙萌萌 邹继同 王晓钢 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期488-495,共8页
Magnetic reconnection processes in three-dimensional(3D)complex field configurations have been investigated in different magneto-plasma systems in space,laboratory,and astrophysical systems.Two-dimensional(2D)features... Magnetic reconnection processes in three-dimensional(3D)complex field configurations have been investigated in different magneto-plasma systems in space,laboratory,and astrophysical systems.Two-dimensional(2D)features of magnetic reconnection have been well developed and applied successfully to systems with symmetrical property,such as toroidal fusion plasmas and laboratory experiments with an axial symmetry.But in asymmetric systems,the 3D features are inevitably different from those in the 2D case.Magnetic reconnection structures in multiple celestial body systems,particularly star-planet-Moon systems,bring fresh insights to the understanding of the 3D geometry of reconnection.Thus,we take magnetic reconnection in an ancient solar-lunar terrestrial magneto-plasma system as an example by using its crucial parameters approximately estimated already and also some specific applications in pathways for energy and matter transports among Earth,ancient Moon,and the interplanetary magnetic field(IMF).Then,magnetic reconnection of the ancient lunar-terrestrial magnetospheres with the IMF is investigated numerically in this work.In a 3D simulation for the Earth-Moon-IMF system,topological features of complex magnetic reconnection configurations and dynamical characteristics of magnetic reconnection processes are studied.It is found that a coupled lunar-terrestrial magnetosphere is formed,and under various IMF orientations,multiple X-points emerge at distinct locations,showing three typical magnetic reconnection structures in such a geometry,i.e.,the X-line,the triple current sheets,and the A-B null pairs.The results can conduce to further understanding of reconnection physics in 3D for plasmas in complex magnetic configurations,and also a possible mechanism for energy and matters transport in evolutions of similar astrophysical systems. 展开更多
关键词 magnetic reconnection multiple X-points complex magneto-plasma system
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Ecological network analysis reveals complex responses of tree species life stage interactions to stand variables
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作者 Hengchao Zou Huayong Zhang Tousheng Huang 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期29-43,共15页
Tree interactions are essential for the structure,dynamics,and function of forest ecosystems,but variations in the architecture of life-stage interaction networks(LSINs)across forests is unclear.Here,we constructed 16... Tree interactions are essential for the structure,dynamics,and function of forest ecosystems,but variations in the architecture of life-stage interaction networks(LSINs)across forests is unclear.Here,we constructed 16 LSINs in the mountainous forests of northwest Hebei,China based on crown overlap from four mixed forests with two dominant tree species.Our results show that LSINs decrease the complexity of stand densities and basal areas due to the interaction cluster differentiation.In addition,we found that mature trees and saplings play different roles,the first acting as“hub”life stages with high connectivity and the second,as“bridges”controlling information flow with high centrality.Across the forests,life stages with higher importance showed better parameter stability within LSINs.These results reveal that the structure of tree interactions among life stages is highly related to stand variables.Our efforts contribute to the understanding of LSIN complexity and provide a basis for further research on tree interactions in complex forest communities. 展开更多
关键词 Tree interactions Life stages Interaction networks Ecological complexity
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