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A New Species of Coniopteris moguqiensis sp. nov. from the middle Jurassic Wanbao Formation in Eastern Inner mongolia, China

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Acta Geologica Sinica(English Edition) 2019年第5期93卷 1317-1324页

作者： ZHANG yujin LIU Bingcai LIANG Fei Shenyang Center of Geological Survey China Geological SurveyShenyang 110034China College of Paleontology Shenyang Normal UniversityShenyang 110034China key Lab of Evolution of Past Life in NE Asia Ministry of Natural ResourcesShenyang 110034China State key Laboratory of Palaeobiology and Stratigraphy(Nanjing Institute of Geology and Palaeontology CAS)Nanjing 210008China

In recent years, an increasing number of plant fossil leaves and petrified woods have been discovered from the middle Jurassic Wanbao Formation in moguqi Town of Inner mongolia, NE China. Here, we describe a new species of Coniopteris moguqiensis sp. nov. preserved as a fragment with fertile and sterile pinnules. The sterile ultimate pinnules are elongate ovate with sphenopteriod type venation, and fertile pinnules are usually isolated, bipinnate at least with the sorus apical, elliptical, 1 mm in diameter;sporangia are almost globular, 100-150 μm in diameter, and the annulus is vertical. In situ spores are rounded-triangular in polar view, 25-30 μm in diameter with sides straight and slightly convex;trilete, laesurae are thin and slightly straight;the exine surface is usually psilate under the light microscope but finely reticuloid sculptured on the proximal view under a scanning electronic microscope. The fern genus Coniopteris usually suggests a warm and humid environment, which is consistent with the palaeoclimatic conditions of petrified wood and megafossil plants. The new discovery further supplements the floral composition of the Wanbao Formation, providing new material for understanding the evolutionary trend and classification of Coniopteris.

关键词： Coniopteris Wanbao Formation in situ spores middle Jurassic Inner mongolia

Oxidative coupling of methane over LaAlO3 perovskite catalysts prepared by a co-precipitation method: Effect of co-precipitation pH value

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Journal of Energy Chemistry 2019年第8期28卷 1-8,I0001页

作者： yujin Sim Jihoon Yoo Jeong-myeong Ha Ji Chul Jung Department of Chemical Engineering Myongji UniversityYongin 17058 Republic of Korea Clean Energy Research Center Korea Institute of Science and TechnologySeoul 02792 Republic of Korea

Oxidative coupling of methane(OCm) was conducted over LaAlO3X catalysts that were prepared by a coprecipitation method using different co-precipitation pH values(X = 6–10). The aim is to investigate the effect of p H values on the catalytic activity of La AlO3 catalysts in this reaction. The results showed that the co-precipitation pH value affected greatly on the formation of chemical species of precipitate precursors in the co-precipitation step, leading to different phases of the finally obtained LaAlO3 *** the co-precipitation pH value increased up to 8, the lanthanum-related phases such as La2 O3 and La(OH)3 were gradually formed as by-products, preventing the formation of LaAlO3 perovskite crystalline structure and facilitating the formation of oxygen vacancies on catalyst surface. However, at pH value of9 or higher, the lanthanum content in the precipitate precursor was increased greatly. Not LaAlO3 perovskite but lanthanum-related phases were developed as main phases, reducing their catalytic activities in this reaction. Among LaAlO3 catalysts, the one prepared at pH = 8 showed the highest C2 yield due to its well-developed oxygen vacancies and electrophilic lattice oxygen. Therefore, the co-precipitation pH value strongly affected the LaAlO3 catalyst activity in OCm reaction. A precious pH control should be required to prepare various perovskite catalysts for the OCm.

关键词： LaAlO3 Perovskite Oxidative coupling of methane Co-precipitation pH value

Phase transition of multi-component(TiZrVNb)C ceramics—Part II:From single phase to multiple phases via adjusting V content

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Journal of Advanced Ceramics 2024年第5期13卷 689-698页

作者： Qingyi kong Lei Chen Sijia Huo kunxuan Li Wenyu Lu yujin Wang Yu Zhou Institute for Advanced Ceramics School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150080China key Laboratory of Advanced Structure‒Function Integrated materials and Green manufacturing Technology Harbin Institute of TechnologyHarbin 150001China National key Laboratory of Precision Hot Processing of metals Harbin Institute of TechnologyHarbin 150001China

To address the relatively mediocre mechanical properties of single-phase multi-component carbide ceramics,a phase transition from a single phase to multiple phases was proposed to achieve superior mechanical properties.A series of(TiZrV_(x)Nb)C_(0.8) ceramics with different V contents were fabricated by spark plasma sintering(SPS).The influence of the V content on the phase composition,microstructural evolution,and mechanical properties was investigated in *** transition behavior from a single phase to multiple phases is discovered and *** formation of the Zr-rich phase and Zr-poor phase can be attributed to the increase in lattice distortion and mixed enthalpy caused by the addition of V.A nanometer lamellar structure with a semi-coherent interface obtained via in situ decomposition is reported for the first time in multi-component carbide *** semi-coherent interfaces with high dislocation density and strain concentration effectively improve the mechanical properties,grain refinement,and multi-phase *** optimal comprehensive mechanical properties of the Vickers hardness(26.3 GPa),flexural strength(369 mPa),and fracture toughness(3.1 mPa·m^(1/2))were achieved for the sample with 20 mol%V.

关键词： multi-component ceramics multiple phases microstructure evolution phase decomposition mechanical properties

Self-powered and broadband germanium/PEDOT:PSS heterojunction photodetectors for near-infrared biomedical imaging applications

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Science China(Technological Sciences) 2021年第11期64卷 2523-2531页

作者： WU QiuYue LIU yujin HUANG XinYue ZHENG Xu HE JieZhong JI Zhong mAI WenJie Siyuan Laboratory Guangdong Provincial Engineering Technology Research Center of Vacuum Coating Technologies and New Energy MaterialsDepartment of PhysicsJinan UniversityGuangzhou 510632China

To develop high-performance photodetectors(PDs) as near-infrared(NIR) imaging sensors, researchers have either proposed new photoelectric materials, introduced complicated interface-processing steps, or created complex optical structures. In this study, we introduce a solution-processed organic material, PEDOT:PSS(PEDOT corresponds to a polymer of 3,4-ethylene dioxythiophene(EDOT), and PSS corresponds to a polystyrene sulfonate), to germanium(Ge) wafers using a convenient spincoating method to improve the photoresponse performance of Ge-based PDs. The Ge wafers and PEDOT:PSS form a heterojunction that reduces the dark current when compared with the Ge Schottky PD(Au/Ge/Ag PD). The experimental results show that the Au/PEDOT:PSS/Ge/Ag heterojunction PD with a bias voltage of 0 V at 1550 nm exhibits a responsivity(R) of 0.26 A/W,a detectivity(D*) of 6.5×1011 Jones, a linear dynamic range(LDR) of 124 d B, and a bandwidth(-3 dB) of 10 k Hz. This implies that the performance of the PD is comparable to that of previously reported Ge-based PDs. Subsequently, a biomedical imaging application of the PD is successfully demonstrated through foreign-body detection. Therefore, it is expected that the selfpowered Au/PEDOT:PSS/Ge/Ag PD will be highly suitable for NIR imaging.

关键词： gemanium photodetectors PEDOT:PSS heterojunction self-powered photodetectors near-infrared biomedical imaging

Interfacial modulation of Polydopamine-Reduced Graphene Oxide for Achieving Highly Conductive and Strong Graphene/Cotton Composite Yarn Toward Smart Wearable Devices

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Advanced Fiber materials 2024年第6期6卷 1798-1812页

作者： yujin Zhang Guowen Zhang Yuqi Dong Yongcai Wu Liqian Yu Yongxiao Bai Institute of Soft‑matter and Advanced Functional materials Gansu Province Carbon New Material Industry Technology CenterSchool of Materials and EnergyLanzhou UniversityLanzhou 730000China

Graphene composite yarns have demonstrated significant potential in the development of multifunctional wearable elec-tronics,showcasing exceptional conductivity,mechanical properties,flexibility,and lightweight ***,their performance is limited by the weak interfacial interaction between the fibers and ***,a polydopamine-reduced graphene oxide(PDA-RGO)interfacial modulation strategy is proposed to prepare graphene-coated cotton yarns with high electrical conductivity and ***-RGO serves as an interfacial bonding molecule that interacts with the cotton yarn(CY)substrate to establish a hydrogen interface,while interconnecting with highly conductive graphene throughπ-π*** developed interface-designed graphene-coated yarn demonstrates an impressive average electrical conductivity of(856.27±7.02)S/m(i.e.,average resistance of(57.57±5.35)Ω).Simultaneously,the obtained conductive yarn demonstrates an exceptional average tensile strength of(172.03±8.03)mPa,surpassing that of primitive CY by approximately 1.59 *** conductive yarns can be further used as low-voltage flexible wearable heaters and high-sensitivity pressure sensors,thus showcasing their remarkable potential for high-performance and multifunctional wearable devices in real-world applications.

关键词： Graphene Interface modulation Conductive yarn Flexible wearable device

Densification,microstructure and mechanical properties of multicomponent(TiZrHfNbTamo)C ceramic prepared by pressureless sintering

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Journal of materials Science & Technology 2021年第13期72卷 23-28页

作者： Wen Zhang Lei Chen Chenguang Xu Wenyu Lu yujin Wang Jiahu Ouyang Yu Zhou Institute for Advanced Ceramics School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China key Laboratory of Advanced Structure-Function Integrated materials and Green manufacturing Technology Harbin Institute of TechnologyHarbin 150001China

A multicomponent(TiZrHfNbTamo)C ceramic has been fabricated by pressureless sintering at temperatures from 2100℃to 2500℃,using an equimolar multicomponent carbide powder synthesized by carbothermal reduction as the starting *** of sintering temperature on densification,microstructure and mechanical properties of the ceramics was *** relative density increases with increasing sintering temperature,and a nearly fully dense sample is achieved by pressureless sintering at 2500℃.Average grain size increases from 3.7 to 15.2μm with increasing sintering temperature from 2300 to 2500℃.The(TiZrHfNbTamo)C ceramic sintered at 2400℃exhibits a single phase fcc structure with homogeneous chemical composition,an average grain size of 7.0μm and a relative density of96.5%,while its measured hardness is 33.2 GPa at 100 mN and 23.2 GPa at 9.8 N.

关键词： multicomponent carbide ceramic Pressureless sintering microstructure mechanical properties

Low thermal conductivity of dense(TiZrHfVNbTa)C_(x) high-entropy carbides by tailoring carbon stoichiometry

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Journal of Advanced Ceramics 2023年第1期12卷 49-58页

作者： Lei CHEN Wen ZHANG Wenyu LU Boxin WEI Sijia HUO yujin WANG Yu ZHOU Institute for Advanced Ceramics School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China key Laboratory of Advanced Structural–Functional Integration materials&Green manufacturing Technology Harbin Institute of TechnologyHarbin 150001China School of materials Science and Chemical Engineering Harbin University of Science and TechnologyHarbin 150001China

Transition metal carbides are promising candidates for thermal protection materials due to their high melting points and excellent mechanical ***,the relatively high thermal conductivity is still a major obstacle to its application in an ultra-high-temperature insulation *** this work,the low thermal conductivity of dense(TiZrHfVNbTa)Cx(x=0.6-1)high-entropy carbides has been realized by adjusting the carbon *** thermal conductivity gradually decreases from 10.6 W·m^(−1)·k^(−1) at room temperature to 6.4 W·m^(−1)·k^(−1) with carbon vacancies *** to enhanced scattering of phonons and electrons by the carbon vacancies,nearly full-dense(97.9%)(TiZrHfVNbTa)C_(0.6) possesses low thermal conductivity of 6.4 W·m^(−1)·k^(−1),thermal diffusivity of 2.3 mm^(2)·s^(−1),as well as electrical resistivity of 165.5μΩ·*** thermal conductivity of(TiZrHfVNbTa)C_(0.6) is lower than that of other quaternary and quinary high-entropy carbide ceramics,even if taking the difference of porosity into account in some cases,which is mainly attributed to compositional complexity and carbon *** provides a promising route to reduce the thermal conductivity of high-entropy carbides by increasing the number of metallic elements and carbon vacancies.

关键词： high-entropy carbides thermal conductivity compositional complexity carbon vacancies

Identification of the Intrinsic Dielectric Properties of metal Single Atoms for Electromagnetic Wave Absorption

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Nano-micro Letters 2022年第2期14卷 107-123页

作者： Xinci Zhang Yanan Shi Jia Xu Qiuyun Ouyang Xiao Zhang Chunling Zhu Xiaoli Zhang yujin Chen key Laboratory of In‑Fiber Integrated Optics College of Physics and Optoelectronic EngineeringHarbin Engineering UniversityHarbin 150001People’s Republic of China College of materials Science and Chemical Engineering Harbin Engineering UniversityHarbin 150001People’s Republic of China School of materials Science and Engineering Zhengzhou UniversityZhengzhou 450001People’s Republic of China

Atomically dispersed metals on N-doped carbon supports(m-N_(xCs)) have great potential applications in various ***,a precise understanding of the definitive relationship between the configuration of metal single atoms and the dielectric loss properties of m-N_(xCs) at the atomic-level is still ***,we report a general approach to synthesize a series of three-dimensional(3D)honeycomb-like m-N_xC(m=mn,Fe,Co,Cu,or Ni) containing metal single *** results indicate that 3D m-N_(xCs) exhibit a greatly enhanced dielectric loss compared with that of the NC *** calculations demonstrate that the density of states of the d orbitals near the Fermi level is significantly increased and additional electrical dipoles are induced due to the destruction of the symmetry of the local microstructure,which enhances conductive loss and dipolar polarization loss of 3D m-N_(xCs),***,these 3D m-N_(xCs) exhibit excellent electromagnetic wave absorption properties,outperforming the most commonly reported *** study systematically explains the mechanism of dielectric loss at the atomic level for the first time and is of significance to the rational design of high-efficiency electromagnetic wave absorbing materials containing metal single atoms.

关键词： metal single atoms Dielectric loss behavior NaCl-templating method Lightweight absorbers Honeycomb-like N-doped nanocarbons

The Growth-Promoting mechanism of Brevibacillus laterosporus AmCC100017 on Apple Rootstock.malus robusta

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Horticultural Plant Journal 2022年第1期8卷 22-34页

作者： Xiaona Wang Jiucheng Zhang Xiaofei Wang Jianping An Chunxiang You Bo Zhou yujin Hao State key Laboratory of Crop Biology College of Horticulture Science and EngineeringShandong Agricultural UniversityTai’anShandong 271018China Department of microbiology College of Life SciencesShandong Agricultural UniversityTai’anShandong 271018China National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources Tai’anShandong 271018China

Plant growth-promoting rhizobacteria(PGPR) located in rhizobacteria soil are beneficial to plant growth and development. A PGPR strain AmCC100017 of Brevibacillus laterosporus synthesizes the plant hormone IAA in a tryptophan-dependent manner. In this study, the AmCC100017 strain was used to treat malus robusta, an excellent natural rootstock for apple production, and assess its ability to promote growth. The fresh weight, dry weight, plant height, and lateral root growth of m. robusta were significantly increased with treatment. The presence of the AmCC100017 strain increased IAA content in m. robusta and promoted root secretion of tryptophan. Colonization of the strain in the roots allowed continuous synthesis of IAA and promoted plant growth. In addition, the photosynthetic efficiency in leaves increased after microbial treatment, and the utilization of nitrogen, zinc, iron, copper and magnesium in leaves was increased, which was conducive to ***, the activities of CAT and SOD, as well as the contents of ROS in plants colonized by AmCC100017 were increased compared to control plants, but the activities of POD and mDA contents were decreased. AmCC100017 strain affected the antioxidant capacity and stress resistance of plants. AmCC100017 strain increased the content of soluble protein and soluble sugar in plants, improved plant metabolic activity and stress resistance. Therefore, AmCC100017 not only increased IAA content and photosynthetic efficiency to promote m. robusta growth, but also affected plant through multiple metabolic pathways.

关键词： malus robusta PGPR phytohormone photosynthetic efficiency