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Crustal magma oxidation state and endowments in porphyry copper deposits

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Science China Earth Sciences 2025年第1期68卷 226-236页

作者： Yumin ai Massimo CHIARADIA Chao WU Huayong CHEN Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of Geochemistry Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Earth Sciences University of Geneva Guangdong Provincial Key Laboratory of Mineral Physics and Materials

Porphyry copper deposits（PCDs） supply the majority of the world's copper（Cu） as well as significant amounts of molybdenum（Mo） and gold（Au）. The formation of these deposits is controlled by a variety of geological factors, among which the magmatic oxidation is one of the focuses of current research. This study investigates the redox characteristics of arc magmas by analyzing the ratio of vanadium（V） to scandium（Sc） and its correlation with the oxygen fugacity （fO2） of magmas from arcs of various crustal thicknesses globally. We compiled an extensive dataset of published V/Sc values and studied the partition coefficients of Vand Sc between minerals and silicate melts across various magmatic environments. The results demonstrate that fractional crystallization of magnetite markedly reduces V/Sc values of the residual melt. Furthermore, magnesium number（Mg#） at the onset of magnetite fractionation is strongly positively correlated with fO2of the equilibrium magma. Based on this,the oxidation of arc magmas from different crustal thicknesses can be evaluated. The result suggests that magmas generated in crusts thicker than 20 km tend to be more oxidized with increasing crust thickness. This trend is attributed to enhanced intracrustal differentiation processes involving garnet and amphibole, particularly in mature island and continental arcs. In contrast,magmas in thinner arc crusts（<20 km）, which are significantly influenced by subducted slab materials, display higher oxidation states than most of their thicker crust counterparts. These findings suggest that both subduction dynamics and crustal thickness play a vital role in determining the oxidation state of arc magmas and, consequently, their capacity to generate PCDs. Highly oxidized, primitive arc magmas are less favorable for PCD formation due to that they tend to experience magnetite fractionation and thus sulfide saturation in the early stage of magma evolution, a process leading to copper depletion. On the contra

关键词： Magma evolution V/Sc systematics Magnetite Oxygen fugacity Porphyry copper deposits

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木质素作为化学工业基础原料的研究及应用

化工新型材料 2012年第5期40卷 132-135页

作者：张应龙韦珍珍张锐昌艾明强黄峰山东商业职业技术学院济南250103 山东大学生命科学学院济南250100

介绍了木质素的来源、元素组成、化学结构及分类,综述了木质素在各传统领域的应用,详细介绍了木素作为化学工业基础原料的研究及应用,并预测了木素的研究趋势。

关键词：木质素基础原料研究应用

Synergistic effect of bonding heterogeneity and phonon localization in introducing excellent thermoelectric properties in layered heteroanionic NdZnSbO material

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Journal of Energy Chemistry 2025年第1期100卷 259-272页

作者： Da Wan Shuwei Tang Shulin Bai Xiaodong Li Peng ai Wanrong Guo Tuo Zheng College of Materials Science and Engineering Liaoning Technical University Faculty of Chemistry Northeast Normal University

Layered rare-earth metal oxides, harnessing the dual properties of oxides and two-dimensional layered materials, exhibit remarkable thermal stability and quantum confinement effects. Therefore, this work adopts the first-principles calculation combined with the Boltzmann transport theory to predict the thermoelectric properties of NdZnSbO compound. The coexistence of weak interlayer van der Waals interactions, robust intralayer ionic bonding, and partial covalent bonding leads to remarkable bonding heterogeneity, which engenders pronounced phonon scattering and imposes constraints on thermal transport along the out-of-plane direction. The weakened chemical bonds induced by the antibonding states, together with the rattling-like behavior of the Zn atom, culminate in the profound anharmonicity in the layered NdZnSbO compound. The weakening bond and heavy element contribute to the softness of phonon modes, which significantly diminishes the phonon group velocity. The redistribution-dominated four-phonon scattering process spans a large optical gap, which effectively reduces the lattice thermal conductivity. The NdZnSbO compound exhibits direct semiconductor characteristic with a bandgap of 0.73 e V by adopting the Heyd-Scuseria-Ernzerhof(HSE06) functional in combination with spin–orbit coupling(SOC) effect. The multi-valley feature of NdZnSbO compound augur favorably for band degeneracy, thus amplifying the power factor. Consequently, an optimal figure-of-merit(ZT) of 3.40 at 900 K is achieved for the n-type NdZnSbO compound. The present study delves deeply insights into the origins for the low thermal conductivity of NdZnSbO compound and proposes an optimization scheme to enhance overall thermoelectric performance.

关键词： Bond strength (chemical)

突出软件应用能力培养的“生物统计学”教学改革探讨

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农产品加工 2019年第21期 116-117,120页

作者：万萍艾明强郑素梅廖婷江西科技师范大学生命科学学院

“生物统计学”是许多专业本科生的基础课程,对于提高学生的培养质量具有重要意义。然而,该课程涉及的数学原理和公式推导使得教学存在困难,并且学生的实际应用能力也较差。探讨将SPSS软件与传统的“生物统计学”教学相结合,在教学内容... 详细信息

“生物统计学”是许多专业本科生的基础课程,对于提高学生的培养质量具有重要意义。然而,该课程涉及的数学原理和公式推导使得教学存在困难,并且学生的实际应用能力也较差。探讨将SPSS软件与传统的“生物统计学”教学相结合,在教学内容、教学方式及考核方式等3个方面进行教学改革,旨在提高该课程的教学质量及学生的培养质量,满足大数据时代对人才培养的要求。

关键词：生物统计学软件 SPSS 教学改革

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温和条件下离子液体对木素降解机制研究

化工新型材料 2014年第6期42卷 186-189页

作者：张应龙张海波杨海莹艾明强王芳芳黄峰山东商业职业技术学院食品药品学院济南250103 山东大学微生物重点实验室济南250103 中国科学院青岛生物能源和生物过程所青岛266071

首次探究了木素在温和条件下经不同离子液体降解机制,降解后的产物用GC-MS进行了鉴定,为研究木素结构提供了理论支持。通过对其产物分析发现,不同的离子液体对木素降解机制不同,降解产物的类型以及含量也都不尽相同。离子液体完全可以... 详细信息

首次探究了木素在温和条件下经不同离子液体降解机制,降解后的产物用GC-MS进行了鉴定,为研究木素结构提供了理论支持。通过对其产物分析发现,不同的离子液体对木素降解机制不同,降解产物的类型以及含量也都不尽相同。离子液体完全可以作为木素降解的溶剂,如果催化剂等条件合适,可以生产出以木素为原料的一些有价值的化工产品。

关键词：木质素降解离子液体

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木素结构降解分析及进展

化工新型材料 2012年第10期40卷 15-17页

作者：张应龙张锐昌张咏梅韦珍珍艾明强黄峰山东商业职业技术学院济南250103 山东大学生命科学学院济南250100

详细综述了木素结构降解分析手段极其进展。从可持续性发展的角度看,研究木素的结构及降解问题,已经越来越变成非常紧迫的任务。未来木素结构的研究仍将面临着巨大挑战。

关键词：木索结构降解进展

De novo synthesis of atropisomeric benzofurans via Cu/SPDO complex catalyzed asymmetric formal [3 + 2] annulation

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Science China Chemistry 2025年第1期68卷 174-180页

作者： Fan-Xiao Meng Xing-Yu Wang Ka Lu Ju-Song Yang Fu-Min Zhang ai-Jun Ma Bao Du Yong-Qiang Tu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University School of Chemistry and Chemical Engineering Shanghai Jiao Tong University School of Biotechnology and Health Sciences Wuyi University

Herein, the de novo synthesis of atropisomeric benzofurans through the Cu/spirocyclic-pyrrolidine-oxazoline(SPDO) complex catalyze asymmetric formal [3 + 2] cycloaddition between quinones and ynamides is explored, producing a range of structurally diverse axially chiral benzofurans in satisfactory yields with good to excellent enantioselectivities. Furthermore, density functional theory calculations were applied to explain the possible reaction mechanism.

关键词： benzofuran atropisomers novel de novo synthetic strategy asymmetric formal [3 + 2] cycladdition Cu/SPDO complex DFT calculations

The interaction between KIF21A and KANK1 regulates dendritic morphology and synapse plasticity in neurons

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Neural Regeneration Research 2025年第1期20卷 209-223页

作者： Shi-Yan Sun Lingyun Nie Jing Zhang Xue Fang Hongmei Luo Chuanhai Fu Zhiyi Wei ai-Hui Tang Hefei National Research Center for Physical Sciences at the Microscale CAS Key Laboratory of Brain Function and DiseaseMinistry of Education Key Laboratory for Membrane-less Organelles and Cellular DynamicsDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui ProvinceChina Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefeiAnhui ProvinceChina CAS Center for Excellence in Molecular Cell Sciences Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui ProvinceChina Department of Neurobiology School of Life SciencesSouthern University of Science and TechnologyShenzhenGuangdong ProvinceChina Brain Research Center Southern University of Science and TechnologyShenzhenGuangdong ProvinceChina

Morphological alterations in dendritic spines have been linked to changes in functional communication between neurons that affect learning and ***-4 KIF21A helps organize the microtubule-actin network at the cell cortex by interacting with KANK1;however,whether KIF21A modulates dendritic structure and function in neurons remains *** this study,we found that KIF21A was distributed in a subset of dendritic spines,and that these KIF21A-positive spines were larger and more structurally plastic than KIF21A-negative ***,the interaction between KIF21A and KANK1 was found to be critical for dendritic spine morphogenesis and synaptic *** of either KIF21A or KANK1 inhibited dendritic spine morphogenesis and dendritic branching,and these deficits were fully rescued by coexpressing full-length KIF21A or KANK1,but not by proteins with mutations disrupting direct binding between KIF21A and KANK1 or binding between KANK1 and *** down KIF21A in the hippocampus of rats inhibited the amplitudes of long-term potentiation induced by high-frequency stimulation and negatively impacted the animals’cognitive *** together,our findings demonstrate the function of KIF21A in modulating spine morphology and provide insight into its role in synaptic function.

关键词： actin cytoskeleton dendrite KANK1 KIF21A microtubule spine morphology spine synaptic plasticity talin1

BER performance analysis of non-Hermitian symmetry OFDM-VLC systems with ADC quantization noise

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Optoelectronics Letters 2025年

作者： Wang Zhongpeng ai Caihua Zhang Lijuan School of Information and Electronic Engineering， Zhejiang University of Science and Technology

Quantization noise caused by analog-to-digital converter (ADC) gives rise to the reliability performance degradation of communication systems. In this letter， a quantized non-hermitian Symmetry (NHS) orthogonal frequency-division multiplexing-based visible light communication (OFDM-VLC) system is presented. In order to analyze the effect of the resolution of ADC on NHS OFDM-VLC， a quantized mathematical model of NHS OFDM-VLC is established. Based on the proposed quantized model， a closed-form bit rate error (BER) Expression is derived. The theoretical analysis and simulation results both confirm the effectiveness of the obtained BER formula in high-resolution ADC. In addition， channel coding is helpful in compensating for the BER performance loss due to the utilization of lower resolution ADC.

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