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| 1 | High-Temperature Metamorphism, Anataxis and Tectonic Evolution of a Mafic Granulite from the Eastern Himalayan Orogen显示文摘The Himalayan Orogen, resulting from the Tertiary collision of Indian and Asian continents, is a natural laboratory for studying metamorphism, partial melting and granite formation of collisional orogens. However, metamorphic and anatectic conditions and timescales of meta-mafic rocks in the Greater Himalayan Sequences(GHS) in the east-central Himalaya remain controversial. In this paper, we conduct a study of petrology and geochronology of mafic granulite from the Eastern Himalayan Syntaxis(EHS). The mafic granulite with abundant leucosome bands occurs as layers within felsic granulites and is well deformed. The granulite consists of garnet, plagioclase, amphibole and quartz with minor clinopyroxene, orthopyroxene, biotite, rutile, titanite and ilmenite. The garnet has growth compositional zoning and contains abundant mineral inclusions in its core. Peak metamorphic mineral assemblage of the granulite is garnet, amphibole, plagioclase, quartz, clinopyroxene and rutile, recording a high-pressure(HP) and high-temperature(HT) peak-metamorphism under conditions of 14–15.5 kbar and 780–790℃ in the presence of melt. The reconstructed clockwise P-T path is characterized by an early heating and burial prograde metamorphism, and late isothermal and cooling decompression retrogression. The granulite witnessed a long lasting HT metamorphism, partial melting and melt crystallization process which began at ca. 39 Ma and lasted to ca. 11 Ma. The present study shows that various high-grade rocks of the GHS in the EHS core experienced similar metamorphic conditions and P-T-t paths, indicating that they occurred as a coherent slab during the subduction and exhumation of Indian lithosphere. The significant melts generated during the prograde metamorphism of the GHS rocks not only contributed to the formation of the Himalayan leucogranite, but also resulted in the rheological weakening and ductile flow of the thickened lower crust of the Himalayan Orogen. | Zeming Zhang Huixia Ding Xin Dong Zuolin Tian Dongyan Kang Hongchen Mu Shengkai Qin Yuanyuan Jiang Mengmei Li | 2018 | Journal of Earth Science2018，29，5： | 7 |
| 2 | Shape description matrix and its applications to color-image retrieval and recognition显示文摘Shape description matrix (SDM) describing regional pixel distribution characteristics of images is defined, with both radial and angular distribution messages taken into account to offer a comprehensive and exact description of the shape characteristics even upon a blurred edge. Using this SDM, a general color histogram (GCH) is developed. Both theoretical and experimental results show that the GCH can be applied to color-image retrievals and recognitions with a high efficiency. | WANG Yi,ZHAI Hongchen,LIANG Yanmei,ZHANG Siyuan & MU Guoguang Institute of Modern Optics,Nankai University,Tianjin 300071,China Key Laboratory of Information Sci-ence and Technology MOE,Tianjin 300071,China | 2004 | Science China(Technological Sciences)2004，47，2： | 3 |
| 3 | Breakdown of Maxwell Garnett theory due to evanescent fields at deep-subwavelength scale显示文摘Deep-subwavelength all-dielectric composite materials are believed to tightly obey the Maxwell Garnett effective medium theory. Here, we demonstrate that the Maxwell Garnett theory could break down due to evanescent fields in deep-subwavelength dielectric structures. By using two-and three-dimensional dielectric composite materials with inhomogeneities at a scale of λ∕100, we show that local evanescent fields generally occur near the dielectric inhomogeneities. When tiny absorptive constituents are placed there, the absorption and transmission of the whole composite will show strong dependence on the positions of the absorptive constituents. The Maxwell Garnett theory fails to predict such position-dependent characteristics because it averages out the evanescent fields. By taking the distribution of the evanescent fields into consideration, we have made a correction to the Maxwell Garnett theory so that the position-dependent characteristics become predictable. We reveal not only the breakdown of the Maxwell Garnett theory, but also a unique phenomenon of 'invisible' loss induced by the prohibition of electric fields at deep-subwavelength scales. We believe our work promises a route to control the macroscopic properties of composite materials without changing their composition, which is beyond the traditional Maxwell Garnett theory. | TING DONG JIE LUO HONGCHEN CHU XIANG XIONG RUWEN PENG MU WANG YUN LAI | 2021 | Photonics Research2021，9，5： | 1 |
| 4 | The Eocene corundum-bearing rocks in the Gangdese arc, south Tibet:Implications for tectonic evolution of the Himalayan orogen显示文摘The genesis of Liangguo corundum deposit in the southern Gangdese magmatic arc, east-central Himalaya, remains unknown. The present study shows that the corundum-bearing rocks occur as lenses with variable sizes in the Eocene gabbro that intruded into marble. These corundum-bearing rocks have highly variable mineral assemblage and mode. The corundum-rich rocks are characterized by containing abundant corundum, and minor spinel, ilmenite and magnetite, whereas the corundum-poor and corundum-free rocks have variable contents of spinel, plagioclase, sillimanite, cordierite, ilmenite and magnetite. The host gabbro shows variable degrees of hydration and carbonization. The corundum grains are mostly black, and rarely blue, and have minor Fe O and TiO_2. The spinel is hercynite, with high Fe O and low Mg O contents. The corundum-bearing rocks have variable but high Al_2O_3, FeO and TiO_2, and low SiO_2 contents. Inherited magmatic and altered zircons of the corundum-bearing rocks have similar U e Pb ages(~47 Ma) to the magmatic zircons of the host gabbro, indicating corundum-bearing rock formation immediately after the gabbro intrusion. We considered that emplacement of gabbro induced the contact metamorphism of the country-rock marble and the formation of silica-poor fluid. The channeled infiltration of generated fluid in turn resulted in the hydrothermal metasomatism of the gabbro, which characterized by considerable loss of Si from the gabbro and strong residual enrichment of Al. The metasomatic alteration probably formed under Pe T conditions of ~2.2 -2.8 kbar and ~650 -700℃. We speculate that SiO_2, CaO and Na_2O were mobile, and Al_2O_3, FeO, TiO_2 and high field strength elements remained immobile during the metasomatic process of the gabbro. The Liangguo corundum deposit, together with metamorphic corundum deposits in Central and Southeast Asia, were related to the Cenozoic Himalayan orogeny, and therefore are plate tectonic indicators. | Zeming Zhang Huixia Ding Xin Dong Zuolin Tian Hongchen Mu Mengmei Li Shengkai Qin Zhixiang Niu Ning Zhang | 2018 | Geoscience Frontiers2018，9，5： | 0 |
| 5 | Ultra-broadband reflectionless Brewster absorber protected by reciprocity显示文摘The Brewster’s law predicts zero reflection of p-polarization on a dielectric surface at a particular angle.However,when loss is introduced into the permittivity of the dielectric,the Brewster condition breaks down and reflection unavoidably appears.In this work,we found an exception to this long-standing dilemma by creating a class of nonmagnetic anisotropic metamaterials,where anomalous Brewster effects with independently tunable absorption and refraction emerge.This loss-independent Brewster effect is bestowed by the extra degrees of freedoms introduced by anisotropy and strictly protected by the reciprocity principle.The bandwidth can cover an extremely wide spectrum from dc to optical frequencies.Two examples of reflectionless Brewster absorbers with different Brewster angles are both demonstrated to achieve large absorbance in a wide spectrum via microwave experiments.Our work extends the scope of Brewster effect to the horizon of nonmagnetic absorptive materials,which promises an unprecedented wide bandwidth for reflectionless absorption with high efficiency. | Jie Luo Hongchen Chu Ruwen Peng Mu Wang Jensen Li Yun Lai | 2021 | Light(Science & Applications)2021，10，5： | 0 |
| 6 | Expert consensus on odontogenic maxillary sinusitis multi-disciplinary treatment显示文摘Odontogenic maxillary sinusitis (OMS) is a subtype of maxillary sinusitis (MS). It is actually inflammation of the maxillary sinus that secondary to adjacent infectious maxillary dental lesion. Due to the lack of unique clinical features, OMS is difficult to distinguish from other types of rhinosinusitis. Besides, the characteristic infectious pathogeny of OMS makes it is resistant to conventional therapies of rhinosinusitis. Its current diagnosis and treatment are thus facing great difficulties. The multi-disciplinary cooperation between otolaryngologists and dentists is absolutely urgent to settle these questions and to acquire standardized diagnostic and treatment regimen for OMS. However, this disease has actually received little attention and has been underrepresented by relatively low publication volume and quality. Based on systematically reviewed literature and practical experiences of expert members, our consensus focuses on characteristics, symptoms, classification and diagnosis of OMS, and further put forward multidisciplinary treatment decisions for OMS, as well as the common treatment complications and relative managements. This consensus aims to increase attention to OMS, and optimize the clinical diagnosis and decision-making of OMS, which finally provides evidence-based options for OMS clinical management. | Jiang Lin Chengshuo Wang Xiangdong Wang Faming Chen Wei Zhang Hongchen Sun Fuhua Yan Yaping Pan Dongdong Zhu Qintai Yang Shaohua Ge Yao Sun Kuiji Wang Yuan Zhang Mu Xian Ming Zheng Anchun Mo Xin Xu Hanguo Wang Xuedong Zhou Luo Zhang | 2024 | International Journal of Oral Science2024，16，1： | 0 |
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