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Molecular cytogenetic study on the plants of Elymus nutans with varying fertility on the Qinghai-Tibet Plateau

Plant Diversity 2022年第6期44卷 617-624页

作者： Bo Liu Xiao-Yan Tao quan-wen Dou Key Laboratory of Adaptation and Evolution of Plateau Biota Northwest Institute of Plateau BiologyChinese Academy of SciencesXiningChina Qinghai Province Key Laboratory of Crop Molecular Breeding XiningChina University of Chinese Academy of Sciences BeijingChina

A molecular cytogenetic investigation was conducted on plants of the allohexaploid species Elymus nutans with varying fertility on the Qinghai-Tibet *** karyotyping revealed that chromosome variants were distributed unevenly among genomes and among different homologue chromosomes in each *** plants with varying fertility exhibited significantly higher numbers of chromosome variants than did the normal fertility samples,although both kinds of plants showed the same pattern of high-to-low polymorphism from the Y to St and H *** and karyotype heterozygosity in the plants with varying fertility were 3-and 13-fold higher than those in normal samples,*** negative correlations were found not only between seed setting rates and total genome heterozygosity but also between seed setting rates and heterozygosity of each genome in the plants of varying *** pairing analysis was performed using genomic in situ hybridization in selected plants of different fertility *** pairing of chromosomes at meiotic metaphase I was mostly bivalent,although univalent,trivalent,quadrivalent,and other polyvalents also occurred;in addition,chromosome configuration forms and frequencies varied among the studied *** results showed that the average number of ring bivalents in the Y genome was significantly higher than those in the St and H *** positive correlations between pollen grain fertility and ring bivalent number were found in the St and H genomes but not in the Y ***,chromosome configuration parameters(total bivalents,numbers of ring and rod bivalents)were found to be significantly correlated with heterozygosity and seed setting rates in the St and H genomes,respectively,but not in the Y *** was inferred that the seed setting rate and pollen grain fertility in *** are strongly influenced by the heterozygosity of each genome,but the Y genome differs from the S

关键词： Chromosome pairing Elymus nutans Fertility FISH and GISH Karyotype variation

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Low Dielectric Benzocyclobutene-type Polymers Based on Facile Synthesis of Linear Fluorinated Monomer

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Chinese Journal of Polymer Science 2023年第11期41卷 1760-1766,I0008页

作者： quan Sun Zi-Wei Yuan wen-Jie Fan Meng-Lu Li wen-Xin Fu Key Laboratory of Science and Technology on High-Tech Polymer Materials Institute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemistry and Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Chemical Biology of Hebei Province College of Chemistry and Environmental ScienceHebei UniversityBaoding 071002China

A linear fluorinated benzocyclobutene-type monomer(4F-bis-BCB) was facilely synthesized by a one-step copper-catalyzed etherification reaction and a simple precipitation post-purification ***,a series of BCB-based polymeric low-dielectric(low-k)materials were obtained by the thermal-induced ring-opening copolymerization of 4F-bis-BCB with divinyl tetramethyl disiloxanebisbenzocyclobutene(DVS-BCB) monomer and further simple thermal curing at high temperature(200-300℃).The resultant fully cured materials demonstrated excellent low dielectric properties at high frequency of 10 GHz(dielectric constant(D_(k))116°),ultra-low water absorption(<0.19% after soaked in water at room temperature for 60 h) and excellent planarization ability(surface roughness<0.56 nm of 3 μm-thick film).Overall,this new fluorinated BCB-type monomer provides us an alternative for the facile preparation of low-k polymeric materials and exhibits great potential for future applications in high-frequency communication and three-dimensional high-density packaging technologies.

关键词： Fluorinated monomer Benzocyclobutene-based polymer Low dielectric material Advanced packaging

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Achieving Safe Deep Reinforcement Learning via Environment Comprehension Mechanism

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Chinese Journal of Electronics 2021年第6期30卷 1049-1058页

作者： PENG Pai ZHU Fei LIU quan ZHAO Peiyao WU wen School of Computer Science and Technology Soochow University

Deep reinforcement learning(DRL), which combines deep learning with reinforcement learning, has achieved great success recently. In some cases, however,during the learning process agents may reach states that are worthless and dangerous where the task fails. To address the problem, we propose an algorithm, referred as Environment comprehension mechanism(ECM) for deep reinforcement learning to attain safer decisions. ECM perceives hidden dangerous situations by analyzing object and comprehending the environment, such that the agent bypasses inappropriate actions systematically by setting up constraints dynamically according to states. ECM, which calculates the gradient of the states in Markov tuple, sets up boundary conditions and generates a rule to control the direction of the agent to skip unsafe states. ECM is able to be applied to basic deep reinforcement learning algorithms to guide the selection of actions. The experiment results show that the algorithm promoted safety and stability of the control tasks.

关键词： multi-agent systems deep learning (artificial intelligence) Markov tuple agent direction Markov processes basic deep reinforcement learning algorithms environment comprehension mechanism safety boundary conditions ECM

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Relativistic Multichannel Theory:Doubly Excited States of Atomic Helium

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Chinese Physics Letters 1998年第3期15卷 175-177页

作者： zou Yu FANG quan-yu LI Jia-ming Institute of Applied Physics and Computational Mathematics Beijing 100088 Center of Atomic and Molecular Sciences Department of PhysicsTsinghua UniversityBeijing 100084 Institute of Physics Chinese Academy of SciencesBeijing 100080

In the report,the recently developed relativistic multichannel theory(RMCT)is a full relativistic non-perturbative method and can be applied to the high-Z atomic ions which have given rise to some recent interests because of researches of inertial confinement fusion and x-ray *** on the RMCT,the positions and widths of doubly excited sp2n^(+),sp2n^(-),and 2pnd ^(1)P_(1) resonances are calculated,which are in agreement with the recent experimental *** sets up a sound foundation on which the RMCT should be applicable to high Z atomic ions.

关键词： relativistic excited positions

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A new triterpene and a saponin from Centella asiatica

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Chinese Chemical Letters 2007年第1期18卷 62-64页

作者： quan Lin Yu Hong quan Duan wen Yuan Gao Yoshihisa Takaishi College of Pharmaceutical Sciences and Biotechnology Tianjin University Tianjin 300072 China School of Pharmacy Tianjin Medical University Tianjin 300070 China School of Agronomy Hebei Normal University of Science ＆ Technology Hebei 066600 China Faculty of Pharmaceutical Sciences University of Tokushima Tokushima 770-8505 Japan

A new triterpene and a saponin, named 2α,3β23-trihydroxyurs-20-en-28-oic acid （1） and 2α,3β,23-trihydroxyurs-20-en-28-oic acid O-α-L-rhanmopyranosyl-（1→4）-O-β-D-glucopyranosyl-（1→6）-O-β-D-glucopyranosyl ester （2）, have been isolated from the aerial part of CenteUa asiatica. Their structures were elucidated by spectral methods, including 2D-NMR spectra.

关键词： Centella asiatica 2α,3β,23-Trihydroxyurs-20-en-28-oic acid 2α,3β,23-Trihydroxyurs-20-en-28-oic acid O-α-L-rhamnopyranosyl-( 1→4)-O-β-D-glucopyranosyl-( 1→6)-O-β-D-glucopyranosyl ester

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Recent advances in chiral aggregation-induced emission fluorogens

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Engineered Regeneration 2022年第3期3卷 323-338页

作者： Rui Hu Yuncong Yuan Meijia Gu You-quan zou Key Laboratory of Combinatorial Biosynthesis and Drug Discovery Ministry of EducationSchool of Pharmaceutical SciencesWuhan UniversityWuhanChina College of Life Sciences Wuhan UniversityWuhanChina TaiKang Center for Life and Medical Sciences Wuhan UniversityWuhanChina

Over the past decade,aggregation-induced emission(AIE)molecules have played a pivotal role in bioimaging,anti-microbial,and photodynamic therapy,and have been at the forefront of several disciplines *** combined with chiral moieties,they can easily collide with dazzling sparks and exhibit exceptional and unique *** the application of chiral recognition and measurement of enantiomeric excess,it can identify chi-ral molecules visually based on color change and precipitation reaction,quantitatively analyze chiral molecules while determining the enantiomeric composition based on the fluorescence intensity change at different wave-lengths,and obtain two parameters about chiral molecules from one measurement,thereby demonstrating its high selectivity,sensitivity and accuracy in chiral *** the field of organic circularly polarized lu-minescent(CPL)materials,the asymmetry(g lum)of common organic light emitting elements is usually between 10−5 and 10−2,whereas the CPL asymmetry factor(g lum)of chiral AIE fluorogens(AIEgens)can reach 1.42,which is very close to the theoretical value of ***,the combination of chiral elements and luminescent groups promotes their adoption in the field of organic CPL *** we have summarized the recent applications of chiral AIEgens in both chiral molecule recognition and circularly polarized organic light-emitting diode(CP-OLED)in order to provide future researchers with a more comprehensive and detailed understanding of chiral AIEgens and to encourage more scientists to contribute to the development of AIEgens.

关键词： Aggregation-induced emission Chiral AIE fluorogens Recognition Circularly polarized luminescent

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Anti-synchronization in Different Hyperchaotic Systems

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Communications in Theoretical Physics 2008年第10期50卷 907-912页

作者： DOU Fu-quan SUN Jian-An DUAN wen-Shan College of Physics and Electronics Engineering Northwest Normal University Lanzhou 730070 China

Based on active control theory, anti-synchronization between two different hyperchaotic systems is investigated. The sufficient conditions for achieving anti-synchronization of two different hyperchaotic systems are derived. Moreover, numerical simulations are presented for hyperehaotic Lorenz-Chen system, hyperchaotic Lorenz-Lu system, and hyperchaotic Chen Lu system to verify the effectiveness and feasibility of the proposed anti-synchronization scheme.

关键词： anti-synchronization hyperchaotic system active control

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Superposition of Coherent States in a Mesoscopic Josephson Junction with Dissipation

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Communications in Theoretical Physics 2001年第10期36卷 473-476页

作者： zou Jian SHAO Bin SU wen-Yong Department of Applied Physics Beijing Institute of Technology Beijing 100081 China Department of Applied Physics Beijing Institute of Technology Beijing 100081 China Department of Applied Physics Beijing Institute of Technology Beijing 100081 China

A mesoscopic Josephson junction with dissipation is considered. Usually the dissipation in the system is described as a consequence of its coupling to a reservoir. By solving the master equation we show that the state... 详细信息

关键词： mesoscopic Josephson junction, superposition of coherent states, dissipation

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Science Letters:Nitrogen doping of activated carbon loading Fe_2O_3 and activity in carbon-nitric oxide reaction

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第5期8卷 707-711页

作者： WAN Xian-kai zou Xue-quan SHI Hui-xiang WANG Da-hui Institute of Environmental Engineering Zhejiang University Hangzhou 310027 China

Nitrogen doping of activated carbon loading Fe2O3 was performed by annealing in ammonia, and the activity of the modified carbon for NO reduction was studied in the presence of oxygen. Results show that Fe2O3 enhances the amount of surface oxygen complexes and facilitates nitrogen incorporation in the carbon, especially in the form of pyridinic nitrogen. The modified carbon shows excellent activity for NO reduction in the low temperature regime （〈500℃） because of the cooperative effect of Fe2O3 and the surface nitrogen species.

关键词： Activated carbon Nitric oxide Doping Iron oxides Catalytic reduction

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Flexible and transparent triboelectric nanogenerator based on high performance well-ordered porous PDMS dielectric film

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Nano Research 2016年第12期9卷 3714-3724页

作者： Xianming He Xiaojing Mu quan wen Zhiyu wen Jun Yang Chenguo Hu Haofei Shi Department of Applied Physics Chongqing University Chongqing 400044 China Key Laboratory of Fundamental Science of Micro/Nano-Device and System Technology Chongqing University Chongqing 400044 China Microsystem Research Center Chongqing University Chongqing 400044 China Key Laboratory of Multi-Scale Manufacturing Technology Chongqing Institute of Green and Intelligent Technology Chinese Academy of Sciences Chongqing 400714 China

A flexible and transparent triboelectric nanogenerator （FT-TENG） has great potential for application in self-powered biosensor systems, electronic skin and wearable electronic devices. However, improving the output performance with little damage to its optical properties is challenging. Herein, we have developed an FT-TENG that has a well-ordered nest-like porous polydimethylsiloxane （NP-PDMS） film and graphene transparent electrodes. The NP-PDMS film with ordered pores is fabricated by hydrochloric acid etching of 500 nm sized ZnO spheres made of aggregated nanoparticles, having a light transmittance of 81.8% and a water contact angle of 118.62°. The FT-TENG based on the NP-PDMS film with a porosity of 12%, gives a maximum output of 271 V and 7.8 μA, which are respectively, 3.7 and 2.1-fold of those of a TENG with a flat PDMS film. The peak output power reaches 0.39 mW with a load resistance of 9.01 MΩ. The dielectric constant and effective thickness of the NP-PDMS film and the capacitance and charge transfer of the FT-TENG are systematically investigated. This work provides a novel and effective method to enhance the performance of FT-TENGs with little damage to their optical properties.

关键词： porouspolydimethylsiloxane(PDMS) surface charge density nanogenerator flexibility transparent electrode

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