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Crustal magma oxidation state and endowments in porphyry copper deposits

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（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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Wireless contactless pressure measurement of an LC passive pressure sensor with a novel antenna for high-temperature applications

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Chinese Physics B 2015年第4期24卷 540-545页

作者：李晨谭秋林薛晨阳张文栋李运芝熊继军 science and Technology on Electronic Test and measurement laboratory North University of China key laboratory of instrumentation science and dynamic measurement Ministry of Education North University of China

In this paper, a novel antenna is proposed for high-temperature testing, which can make the high-temperature pressure characteristics of a wireless passive ceramic pressure sensor demonstrated at up to a temperature of 600℃. The design parameters of the antenna are similar to those of the sensor, which will increase the coupling strength between the sensor and testing antenna. The antenna is fabricated in thick film integrated technology, and the properties of the alumina ceramic and silver ensure the feasibility of the antenna in high-temperature environments. The sensor, coupled with the ceramic antenna, is investigated using a high-temperature pressure testing platform. The experimental measurement results show that the pressure signal in a harsh environment can be detected by the frequency diversity of the sensor.

关键词： ceramic antenna contactless pressure measurement high-temperature application wireless passive pressure sensor

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A Phase Readout Method for Wireless Passive Sensor Used in Pressure measurement System

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Chinese Journal of Electronics 2015年第4期24卷 702-708页

作者： HONG Yingping LIANG Ting ZHENG Tingli ZHANG Hairui LIU Wenyi XIONG Jijun key laboratory of instrumentation science & dynamic measurement Ministry of Education North University of China science and Technology on Electronic Test & measurement laboratory North University of China

A phase difference detection method used for reading the resonant frequency through mutual coupling is designed to meet the pressure measurement in harsh environments, and a testing device of integrated modular by developing the hardware circuits is *** and discussion of the novel theoretical model in the phase readout system is presented, and a pressure test platform based on the phase difference detection is also established, which is to measure the frequency of a LC resonant sensor on the basis of 96% alumina ceramic substrate. The experimental results show that the proposed phase difference readout system presents sweep-frequency detection in the range of 1–100MHz bandwidth, and a high frequency resolution of 0.006 MHz. Sensitivity of the sensor is approximately 0.225 MHz/bar from 1 bar to 2 bar. The accuracy and functionality of the phase readout system have emphasized a wider engineering application range, so that we can make it possible that the wireless passive LC resonant sensor revolves well in practical engineering occasions outside the laboratory environment.

关键词： LC resonant sensor Resonant frequency Phase difference detection Pressure test

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Comparison between photoluminescence spectroscopy and photoreflectance spectroscopy in CuGaSe_2 epilayer

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Chinese Physics B 2008年第4期17卷 1454-1460页

作者：甄国涌菅傲群徐宏妍薛晨阳张文栋 key laboratory of instrumentation science & dynamic measurement (North University of China) Ministry of Education and National Key Laboratory For Electronic Measurement Technology North University of China

Photoluminescence （PL） spectroscopy and photoreflectance （PR） spectroscopy are very useful techniques for studying the properties of materials. In this paper, the same material of Cu-rich metal-organic vapour phase epitaxy （MOVPE） grown CuGaSe2 layer is investigated in a temperature range from 20 to 300 K to compare these two techniques. Both PL and PR spectra appear red shifted, less intense and broadened. The temperature dependence of interband transitions is studied by using the Manoogian Leclerc equation. The values of the band gap energy at T=0K and the effective phonon temperature are estimated. The temperature dependences of intensities and broadenings of PL and PR spectral lines are also analysed. Based on the results of the comparison, the features and applications of the PL and PR can be shown in detail.

关键词： photoluminescence photoreflectance comparison CuGaSe2

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The composition of magmatic-hydrothermal fluids and their related metal mineralization

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science China Earth sciences 2025年第1期68卷 208-225页

作者： Qihai SHU Jun DENG State key laboratory of Geological Processes and Mineral Resources School of Earth Sciences and Resources China University of Geosciences Frontiers science Center for Deep-time Digital Earth China University of Geosciences

Magmatic hydrothermal deposits are important sources of many bulk, precious, and rare metals, and have attracted interest from both academic and industrial communities. However, it is still unclear if the major enrichment of the ore-forming metals occurs in the parental magma source region, during the magma evolution, or after the fluid exsolution. Fluid inclusions trapped in hydrothermal minerals crystallized in the early, high-temperature stage before metal precipitation record information close to that of the initially exsolved magmatic fluids, which are helpful in revealing whether the metals have been already significantly enriched prior to the hydrothermal stage. In this study, available compositional data of such early-stage fluid inclusions from magmatic hydrothermal systems globally have been compiled. The results indicate that the concentrations of Cu,Sn, and W respectively from the Cu-, Sn-, and W-mineralized fluids are significantly higher than the hydrothermal systems that do not produce ores with the corresponding metals. This suggests that Cu, Sn, and W could have already been enriched in the magma source and/or magma evolution stage. The Mo concentrations show no difference between Mo-mineralized and Mobarren fluid systems, indicating no significant pre-enrichment in the source region or during the magma evolution. This also implies that an efficient collection of Mo from a large volume of magmas is required to account for the formation of a large Mo deposit. Almost all the hydrothermal fluids contain high concentrations of Fe and Zn-Pb, but only a few of them eventually form Fe or Zn-Pb deposits, reflecting an important role of the hydrothermal evolution process on the selective metal *** above results indicate that different metals are enriched in different stages of a magmatic hydrothermal system, and that the major roles played in the formation of a deposit vary with the metal types. In addition to the metal concentrations in the o

关键词： Magmatic hydrothermal deposits Fluid inclusions LA-ICP-MS Metal enrichment Mineralization mechanism

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Intermolecular reductive coupling of aliphatic ketones with alkynes and alkenes by BCN photocatalysts

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science China Chemistry 2025年第1期68卷 181-185页

作者： Yanping Xia Luyang Sun Jiajia Cheng Sibo Wang Meifang Zheng Xinchen Wang State key laboratory of Photocatalysis on Energy and Environment College of Chemistry Fuzhou University

A photocatalytic process was developed for intermolecular reductive coupling of aliphatic ketones with alkynes/alkenes to furnish tertiary alcohols. Mechanistic studies support that boron carbonitrides(BCN) promote the single electron reduction of unactivated aliphatic ketones to generate ketyl radicals with visible light irradiation, which then react with alkynes and alkenes to afford the allylic and aliphatic alcohols, respectively. The heterogeneous photocatalytic system is compatible with diverse substrates including pharmaceutical-related molecules(43 examples) with reusability and scale-up experiments, verifying the complementary synthetic utility of this method to the homogeneous catalysts.

关键词： aliphatic ketones ketyl radical intermolecular cross-coupling tertiary alcohols

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Recent Strategies and Advances in Hydrogel‑Based Delivery Platforms for Bone Regeneration

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Nano-Micro Letters 2025年第3期17卷 389-439页

作者： Xiao Wang Jia Zeng Donglin Gan Kun Ling Mingfang He Jianshu Li Yongping Lu Scientific and Technological Innovation Center for Biomedical Materials and Clinical Research Guangyuan Key Laboratory of Multifunctional Medical HydrogelGuangyuan Central HospitalGuangyuan 628000People’s Republic of China Jiangsu Collaborative Innovation Center of Biomedical Functional Materials Jiangsu Key Laboratory of Bio‑Functional MaterialsSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023People’s Republic of China College of Polymer science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065People’s Republic of China

Bioactive molecules have shown great promise for effectively regulating various bone formation processes,rendering them attractive therapeutics for bone ***,the widespread application of bioactive molecules is limited by their low accumulation and short half-lives in *** have emerged as ideal carriers to address these challenges,offering the potential to prolong retention times at lesion sites,extend half-lives in vivo and mitigate side effects,avoid burst release,and promote adsorption under physiological *** review systematically summarizes the recent advances in the development of bioactive molecule-loaded hydrogels for bone regeneration,encompassing applications in cranial defect repair,femoral defect repair,periodontal bone regeneration,and bone regeneration with underlying ***,this review discusses the current strategies aimed at improving the release profiles of bioactive molecules through stimuli-responsive delivery,carrier-assisted delivery,and sequential ***,this review elucidates the existing challenges and future directions of hydrogel encapsulated bioactive molecules in the field of bone regeneration.

关键词： Hydrogel Bone regeneration Bioactive molecules Drug delivery Nano-/microscale carriers

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COMPrompter: reconceptualized segment anything model with multiprompt network for camouflaged object detection

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science China(Information sciences) 2025年第1期68卷 189-203页

作者： Xiaoqin ZHANG Zhenni YU Li ZHAO Deng-Ping FAN Guobao XIAO Zhejiang Province key laboratory of Intelligent Informatics for Safety and Emergency Wenzhou University Nankai International Advanced Research Institute (SHENZHEN FUTIAN) College of Computer science Nankai University School of Computer science and Technology Tongji University

We rethink the segment anything model(SAM) and propose a novel multiprompt network called COMPrompter for camouflaged object detection(COD). SAM has zero-shot generalization ability beyond other models and can provide an ideal framework for COD. Our network aims to enhance the single prompt strategy in SAM to a multiprompt strategy. To achieve this, we propose an edge gradient extraction module, which generates a mask containing gradient information regarding the boundaries of camouflaged objects. This gradient mask is then used as a novel boundary prompt, enhancing the segmentation process. Thereafter, we design a box-boundary mutual guidance module, which fosters more precise and comprehensive feature extraction via mutual guidance between a boundary prompt and a box prompt. This collaboration enhances the model's ability to accurately detect camouflaged objects. Moreover, we employ the discrete wavelet transform to extract high-frequency features from image embeddings. The high-frequency features serve as a supplementary component to the multiprompt ***, our COMPrompter guides the network to achieve enhanced segmentation results, thereby advancing the development of SAM in terms of COD. Experimental results across COD benchmarks demonstrate that COMPrompter achieves a cutting-edge performance, surpassing the current leading model by an average positive metric of 2.2% in COD10K. In the specific application of COD, the experimental results in polyp segmentation show that our model is superior to top-tier methods as well. The code will be made available at https://***/guobaoxiao/COMPrompter.

关键词： segment anything model camouflaged object detection boundary prompt

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Microspheres trigged-stress concentration regulating piezoelectric properties of PVDF/elastomer composites

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science China Chemistry 2025年

作者： Wenxian Zhang Jiahong Yang Qijun Sun Lu Peng Tong Lin Shouke Yan Xiaoli Sun State key laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of Sciences State key laboratory of Separation Membranes and Membrane Processes School of Textile Science and EngineeringTiangong University key laboratory of Rubber-Plastics of Ministry of Education Shandong Provincial Key Laboratory of Rubber-PlasticsQingdao University of Science & Technology

Wearable self-powered piezoelectric pressure sensors are attracting tremendous ***,fabricating a high-sensitive elastic piezoelectric sensor for a broad response range remains ***,we assemble polar poly（vinylidene fluoride）(PVDF) microsphere-elastomer composites,achieving high-sensitive and wide-responsive pressure *** polar PVDF microspheres are produced cost-effectively through phase separation,enabling *** piezoelectric composite （PC） film demonstrates low Young’s modulus,and excellent anti-fatigue ***,the PC-based piezoelectric sensor exhibits a rather high sensitivity of 540 mV N-1in a wide sensing range （5–40 N）,240 times greater than the PVDF film-based sensor and comparable to the inorganic piezoelectric *** excellent performance is attributed to the highest average stress concentration on the spherical PVDF coupled with the remarkable deformation of dipoles of spherical PVDF in the flexible *** on excellent performance,this piezoelectric sensor achieves precise recognition of motions and sound *** high-sensitive flexible piezoelectric sensor enabling large area production with ultralow price exerts great potential in smart monitoring and intelligent robots.

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Anomalous quality factor evolution of induced transparency in a virtualized coupled-oscillator system

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science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 148-155页

作者： Yunhan Yang Han Jia Tuo Liu Yuzhen Yang Jun Yang key laboratory of Noise and Vibration Research Institute of Acoustics Chinese Academy of Sciences University of Chinese Academy of sciences State key laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences

The phenomenon of induced transparency, characterized by a high quality(Q) factor, holds significant importance in the fields of high-precision sensing, energy storage and wave manipulation. Conventional transparency systems are often constrained by the limited experimentally accessible parameter space and the lack of independent control over intrinsic parameters, thereby hindering advanced research on high-Q effects. Here we propose a virtualized coupled-oscillator system that enables reconfigurable induced transparency in the reflection spectrum. By virtually incorporating a pair of coupled oscillators into an individual acoustic meta-atom, we achieve the manipulation of induced transparency in a decoupled, wide-ranging, and elaborate manner. Exploiting the diverse evolutions across the intrinsic parameter space, we show experimentally a counter-intuitive increase in the Q-factor of the transparency window, which is attributed to the enhanced dissipation of the bright ***, a constant group delay at the center frequency is observed accompanying this evolution. Our work demonstrates an intriguing platform as well as a novel strategy to engineer high-Q induced transparency phenomenon, and paves the way towards applications in programmable acoustic sensors, filters and slow-wave devices.

关键词： induced transparency acoustic meta-atom high quality-factor scattering programmable intrinsic parameter

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