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Nano Research 2025年第1期18卷 217-224页

作者： Taolue Sun Chen Jian gang Wang Hui Zhao Guoliang zhang Zengxi Li Chunshan Li State Key Laboratory of Mesoscience and Engineering CAS Key Laboratory of Green Process and EngineeringBeijing Key Laboratory of Ionic Liquids Clean ProcessInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China Huizhou Institute of Green Energy and Advanced Materials Huizhou 516081China Advanced Energy Science and Technology Guangdong Laboratory Huizhou 516081China

Although the nickel-based catalyst is able toexhibit comparative catalytic activity to noble metal formethyl acrylate hydrogenation,it requires strict reactioncondition,which can be improved by regulation ofcoordination *** this study,we constructed akind of Ni single-atom coordinated with N and S(Ni-NSC)through the pyrolysis of organic Ni-based precursors at600℃.The existence and fine structure of Ni single-atom were confirmed by the spherical electron microscopicobservation in combination with the X-ray absorption spectroscopy(XAS)*** addition,the catalytichydrogenation assessment suggested that the as-prepared Ni-NSC catalyst exhibited higher activity and stability than theNi/NSC supported catalyst prepared by incipient wetness impregnation *** remarkable catalytic activity was dueto the high dispersion and density of Ni single-atom and weak adsorption energy of intermediates on these Ni sites.

关键词： methyl acrylate mild hydrogenation Ni single-atom coordination environment adsorption energy

Functional Characterization of Mi, a Root-knot Nematode Resistance Gene from Tomato （ Lycopersicon esculentum L.）

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Journal of Integrative Plant Biology 2006年第12期48卷 1458-1465页

作者： ru-gang Chen Li-Ying zhang Jun-Hong zhang Wei zhang Xue Wang Bo Ouyang Han-Xia Li Zhi-Biao Ye National Key Laboratory of Crop Genetic Improvement Wuhan 430070 China National Center for Vegetable Improvement Huazhong Agricultural University Wuhan 430070 China

Root-knot nematodes （Meloidogyne spp.） cause major economic damage to numerous crop species around the world. Plant resistance is the most important attribute that is able to suppress invasion by the rootknot nematodes. In the present study, a candidate root-knot nematode resistance gene （Mi） was isolated from the resistant tomato （Lycopersicon esculentum L.） line RN-1. Expression profiling analysis revealed that this gene was expressed specifically in the roots, stems, and leaves, but not in the flowers or fruits. To verify the real function of this candidate gene, both sense and inteference RNA （RNAi） vectors were constructed. We obtained 31 transgenic plants with between one and seven copies of T-DNA inserts of sense Mi from two nematode-susceptible tomato cultivars as assayed by polymerase chain reaction （PCR） and Southern blotting analysis. Reverse transcription-PCR analysis revealed that expression levels of the Mi gene varied in different transgenic plants. Nematode assays showed that the resistance to root-knot nematodes was significantly improved in some transgenic lines compared with untransformed susceptible controls and that the resistance was heritable in selfed progeny. Loss of function via RNAi further confirmed the role of the Mi gene and the original resistant lines became susceptible to root-knot nematodes.

关键词： Mi gene overexpression RNAi root-knot nematode tomato

Upcycling of polyethylene terephthalate to1,4-cyclohexanedimethanol in water

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Science China Chemistry 2025年

作者： Shuhui Fang Zhiwen Gao Xinrui Shi Min zhang Wei zhang Yue Liu State Key Laboratory of Petroleum Molecular & Process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal University Engineering Center for Sustainable Carbon Science and Technology East China Normal University Institute of Eco-Chongming

The recycling of waste polyethylene terephthalate（PET）, an extensively used polymer as plastic and fiber materials, has become an urgent topic due to the rapid generation and accumulation of plastic waste into the environment. Current chemical recycling approaches to depolymerize and convert PET into 1,4-cyclohexanedimethanol（CHDM）, an important chemical in the production of advanced polyesters, predominantly use organic solvents, such as alcohols or dioxane. Herein, we developed an environmentally friendly and economically viable pathway for converting PET to CHDM using water as the solvent. In this process, PET is sequentially hydrolyzed in water, hydrogenated to 1,4-cyclohexane dicarboxylic acid（CHDA）, and then reduced to CHDM. The PET conversion rate is self-enhanced in aqueous medium via acid-catalyzed hydrolysis by the generated CHDA intermediate. A Pd-based catalyst（e.g., Pd/C） selectively hydrogenates the arene ring of the PET monomer, terephthalic acid intermediate, and a ru-Sn/C bimetallic catalyst reduces its COOH to CH2OH group. At optimized reaction conditions, a complete conversion of PET and 80.1% yield of CHDM are obtained. Alternatively, this approach can also efficiently produce CHDA from PET, with a yield up to 86.4%.

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Hot tearing susceptibility of Fe-20.96Cr-2.13Ni-0.15N-4.76Mn-0.01Mo duplex stainless steel

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Journal of Iron and Steel Research International 2017年第4期24卷 421-425页

作者： Zhi-qiang Wei Xiang-ru Chen Hong-gang Zhong Qi-jie Zhai gang Wang State Key Laboratory of Advanced Special Steel&Shanghai Key Laboratory of Advanced Ferrometallurgy&School of Materials Science and Engineering Shanghai UniversityShanghai 200072China

The hot tearing susceptibility of a Fe-20.96Cr-2.13Ni-0.15N-4.76Mn-0.01 Mo duplex stainless steel was investigated using method of constrained solidification shrinkage in one *** apparatus for realtime measuring the contraction stress and temperature during solidification was developed,which can achieve the in-situ observation of melting and solidification and avoid the large temperature gradient of casting under the condition of *** results show that the contraction stress increases significantly when the core temperature of casting reaches the liquidus *** contraction stress is released when the core temperature of casting reaches 1456°*** this temperature,the hot tearing susceptibility of duplex stainless steel is the *** decreasing the core temperature to 1363°C,the slope of contraction stress increases,which is related to the ferrite-to-austenite transformation.

关键词： Duplex stainless steel Hot tearing Solidification Contraction stress Core temperature

Sliding mode control of reaction flywheel-based brushless DC motor with buck converter

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Chinese Journal of Aeronautics 2013年第4期26卷 967-975页

作者： Liu gang zhang Cong School of Instrumentation Science and Opto-electronics Engineering Beihang University

Reaction flywheel is a significant actuator for satellites＇ attitude control. To improve output torque and rotational speed accuracy for reaction flywheel, this paper reviews the modeling and control approaches of DC-DC converters and presents an application of the variable structure system theory with associated sliding regimes. Firstly, the topology of reaction flywheel is constructed. The small signal linearization process for a buck converter is illustrated. Then, based on the state averaging models and reaching qualification expressed by the Lee derivative, the general results of the sliding mode control （SMC） are analyzed. The analytical equivalent control laws for reaction flywheel are deduced detailedly by selecting various sliding surfaces at electromotion, energy consumption braking, reverse connection braking stages. Finally, numerical and experimental examples are presented for illustrative purposes. The results demonstrate that favorable agreement is established between the simulations and experiments. The proposed control strategy achieves preferable rotational speed regulation, strong rejection of modest disturbances, and high-precision output torque and rotational speed tracking abilities.

关键词： DC-DC converter Flywheels State averaging model Sliding mode control Sliding surface Topology

Current Progress of Hf(Zr)-Based High-k Gate Dielectric Thin Films

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Journal of Materials Science & Technology 2007年第4期23卷 433-448页

作者： gang HE Lide zhang Key Laboratory of Materials Physics Institute of Solid State Physics Chinese Academy of Sciences Hefei 230031 China　

With the continued downscaling of complementary metal-oxide-semiconductor field effect transistor dimensions, high-dielectric constant （high-k） gate materials, as alternatives to SiO2, have been extensively investigated. Hf （Zr）-based high-k gate dielectric thin films have been regarded as the most promising candidates for high-k gate dielectric according to the International Technology Roadmap for Semiconductor due to their excellent physical properties and performance. This paper reviews the recent progress on Hf （Zr）-based high-k gate dielectrics based on PVD （physical vapor deposition） process. This article begins with a survey of various methods developed for generating Hf （Zr）-based high-k gate dielectrics, and then mainly focuses on microstructure, synthesis, characterization, formation mechanisms of interfacial layer, and optical properties of Hf （Zr）-based high-k gate dielectrics. Finally, this review concludes with personal perspectives towards future research on Hf （Zr）-based high-k gate dielectrics.

关键词： Hf (Zr)-based high-k gate dielectric PVD Optical properties metal-oxide-semiconductor

Symmetry dictionary on charge and spin nonlinear responses for all magnetic point groups with nontrivial topological nature

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National Science Review 2023年第11期10卷 103-109页

作者： Zhi-Fan zhang Zhen-gang Zhu gang Su School of Physical Sciences University of Chinese Academy of Sciences School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of Sciences CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of Sciences Kavli Institute for Theoretical Sciences University of Chinese Academy of Sciences

Recently, charge or spin nonlinear transport with nontrivial topological properties in crystal materials has attracted much attention. In this paper, we perform a comprehensive symmetry analysis for all 122 magnetic point groups(MPGs) and provide a useful dictionary for charge and spin nonlinear transport from the Berry curvature dipole, Berry connection polarizability and Drude term with nontrivial topological *** results are obtained by conducting a full symmetry investigation of the matrix representations of six nonlinear response tensors. We further identify every MPG that can accommodate two or three of the nonlinear tensors. The present work gives a solid theoretical basis for an overall understanding of the second-order nonlinear responses in realistic materials.

关键词： nonlinear response magnetic point group matrix representation

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动车组齿轮箱油中硫含量的红外光谱分析

光谱学与光谱分析 2025年第1期45卷 239-245页

作者：杜瑾瑶贺石中杨智宏张琳颖张静茹广州机械科学研究院有限公司设备润滑与检测研究所广东广州510530 工业摩擦润滑技术国家地方联合工程研究中心广东广州510530

针对高铁动车组牵引系统中齿轮箱润滑油中硫元素损失较快的问题,需要对在用齿轮油硫含量进行监测,以确定最佳的换油时机。分析了红外光谱图中齿轮油含硫添加剂特征吸收峰的衰减机制;选择与硫含量相关性最高的1164 cm-1特征峰的峰高作为... 详细信息

针对高铁动车组牵引系统中齿轮箱润滑油中硫元素损失较快的问题,需要对在用齿轮油硫含量进行监测,以确定最佳的换油时机。分析了红外光谱图中齿轮油含硫添加剂特征吸收峰的衰减机制;选择与硫含量相关性最高的1164 cm-1特征峰的峰高作为输入变量构建了一元线性回归模型(LR),采用5折交叉验证下的测试集R^(2)确定最佳主成分个数构建了偏最小二乘回归模型(PLSR),最后根据偏最小二乘回归系数优选了6个特征吸收峰用于构建特征峰优化后的PLSR模型(RF-PLSR)。采用所建的模型分别对预测集39个油样进行预测,结果表明一元线性回归模型和偏最小二乘回归模型均具有很好的预测能力。一元线性回归模型的预测R^(2)为0.961,RMSE为973.1,RPD为5.084。PLSR模型和特征峰优化后的RF-PLSR模型的预测R^(2)分别为0.997和0.994,RMSE分别为250.1和376.3,RPD分别为19.780和13.149。说明经过特征峰优化后建立的RF-PLSR模型在降低模型复杂度的同时,仍可以保持较高的精度和预测能力,由于消除了不相关变量的信息,使模型的可解释性更好。红外光谱技术为齿轮油中硫含量的检测提供了一种可靠而精确的方法,为齿轮油的状态监测提供一种可行的解决方案。

关键词：齿轮箱油硫含量红外光谱在用油监测

Tangent-impulse transfer from elliptic orbit to an excess velocity vector

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Chinese Journal of Aeronautics 2014年第3期27卷 577-583页

作者： zhang gang zhang Xiangyu Cao Xibin Research Center of Satellite Technology Harbin Institute of Technology National and Local United Engineering Research Center of Small Satellite Technology

The two-body orbital transfer problem from an elliptic parking orbit to an excess veloc-ity vector with the tangent impulse is studied. The direction of the impulse is constrained to be aligned with the velocity vector, then speed changes are enough to nullify the relative velocity. First, if one tangent impulse is used, the transfer orbit is obtained by solving a single-variable function about the true anomaly of the initial orbit. For the initial circular orbit, the closed-form solution is derived. For the initial elliptic orbit, the discontinuous point is solved, then the initial true anomaly is obtained by a numerical iterative approach; moreover, an alternative method is proposed to avoid the singularity. There is only one solution for one-tangent-impulse escape trajectory. Then, based on the one-tangent-impulse solution, the minimum-energy multi-tangent-impulse escape trajectory is obtained by a numerical optimization algorithm, e.g., the genetic method. Finally, several examples are provided to validate the proposed method. The numerical results show that the minimum-energy multi-tangent-impulse escape trajectory is the same as the one-tangent-impulse trajectory.

关键词： Elliptic orbit Escape trajectory Excess velocity vector Orbital transfer Tangent impulse

The complexes of multiimidazole with copper(Ⅰ) display tyrosinase activity

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Chinese Chemical Letters 2007年第10期18卷 1278-1280页

作者： Rong Xiao Xiao Yu Su ru gang Xie College of Chemistry Sichuan University Chengdu 610064 China

The six multiimidazole copper（Ⅰ） complexes are utilized to mimic tyrosinase. The main product is 3,5-di-t-butylcatechol from o-hydroxylation of the substrate 2,4-di-t-butylphenol. The highest yield of catechol is up to 82.2% and selectivity 94.8% by [Cu（Ⅰ）2（3b）（MeCN）2]（CIO4）2 and O2 under mild conditions, which are found to be more efficient than that already reported.

关键词： Multiimidazole dicopper(Ⅰ) complex o-Hydroxylation Catechol Tyrosinase model