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N-Doped porous carbon supported palladium nanoparticles as a highly efficient and recyclable catalyst for the Suzuki coupling reaction

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Chinese Chemical Letters 2016年第1期27卷 149-154页

作者： Li Zhang Wen-Huan Dong Ning-Zhao Shang Cheng Feng shu-tao gao Chun Wang College of Science Agricultural University of Hebei

A new catalyst, Pd particles supported on the N-doped porous carbon（PC） derived from Zn-based metal-organic frameworks（zeolitic imidazolate framework： ZIF-8）, was successfully prepared for the first *** as-prepared catalyst was designated as N-doped PC-Pd, and characterized by X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, scanning electron microscope, N_2 adsorption and inductively coupled plasma atomic emission spectroscopy. The N-doped PC-Pd composite exhibited high catalytic activity toward the Suzuki-Miyaura cross-coupling reactions. The yields of the products were in the range of 90%-99%. The catalyst could be readily recycled and reused at least 6 consecutive cycles without a significant loss of its catalytic activity.

关键词： Suzuki-Miyaura coupling reaction Pd catalyst N-Doped nanoporous carbon Metal-organic frameworks

An efficient synthesis of 1,5-benzodiazepine derivatives catalyzed by boric acid

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Chinese Chemical Letters 2009年第8期20卷 905-908页

作者： Xin Zhou Mei Yue Zhang shu tao gao Jing Jun Ma Chun Wang Chao Liu Hebei Key Laboratory of Bioinorganic Chemistry College of Sciences Agricultural University of Hebei Baoding 071001 China

1,5-Benzodiazepine derivatives have been synthesized by the condensation of o-phenylenediamines and ketones in the presence of boric acid as catalyst under mild conditions. This method is simple, environmentally benign and high yielding. ？2009 Chun Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： 1,5-Benzodiazepincs o-Phenylenediamines Boric acid Synthesis

Macro-mechanics and Microstructure of Nanomaterial-modified Geopolymer Concrete: A Comprehensive Review

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 204-214页

作者： WANG tao FAN Xiangqian gao Changsheng QU Chiyu The National Key Laboratory of Water Disaster Prevention Nanjing Hydraulic Research InstituteNanjing 210024China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China School of Water Conservancy and Transportation Zhengzhou UniversityZhengzhou 450001China

We have described in detail the effects of nano-SiO_(2),nano-CaCO_(3),carbon nanotubes,and nano-Al_(2)O_(3) on geopolymer concrete from the perspectives of macro mechanics and *** existing research results show that the mechanism of nano-materials on geopolymer concrete mainly includes the filling effect,nucleation effect,and bridging effect,the appropriate amount of nano-materials can be used as fillers to reduce the porosity of geopolymer concrete,and can also react with Ca(OH)2 to produce C-S-H gel,thereby improving the mechanical properties of geopolymer *** optimum content of nano-SiO_(2) is between 1.0%and 2.0%.The optimum content of nano-CaCO_(3) is between 2.0%and 3.0%.The optimum content of carbon nanotubes is between 0.1%and 0.2%.The optimum content of nano-Al_(2)O_(3) is between 1.0%and 2.0%.The main problems existing in the research and application of nanomaterial-modified geopolymer concrete are summarized,which lays a foundation for the further application of nanomaterial in geopolymer concrete.

关键词： nanomaterials low carbon geopolymer concrete macro-mechanics microstructure

US-2020全自动尿沉渣分析仪的临床应用评价

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国外医学（临床生物化学与检验学分册） 2005年第3期26卷 138-140页

作者：陶树高广州市第一人民医院检验科 510180

目的　评估重庆天海 US 2020 全自动尿沉渣分析仪的性能及临床应用。方法　用pH6.5的新鲜尿液配制红细胞与5个量级单位作正确分析,用双盲法对同一标本中有形成分重复冲池数10次,求出其CV%。并随机选择120份尿液标本,分别用重庆天海US 2... 详细信息

目的　评估重庆天海 US 2020 全自动尿沉渣分析仪的性能及临床应用。方法　用pH6.5的新鲜尿液配制红细胞与5个量级单位作正确分析,用双盲法对同一标本中有形成分重复冲池数10次,求出其CV%。并随机选择120份尿液标本,分别用重庆天海US 2020全自动尿沉渣分析仪法、牛鲍氏板计数对红细胞、白细胞、上皮细胞、管型作可比性比较。结果　红细胞与5个数量级的理论值与实测值的误差 0. 05,无显著性差异。红细胞携带污染率为0.21%,白细胞携带污染率为0.45%,上皮细胞及管型携带污染率为 0。稀释试验显示良好线性范围。结论　重庆天海US 2020全自动尿沉渣分析仪主要指标符合要求,自动化程度高,尿沉渣检查标准、规范。其快速准确,操作简便,是目前较理想的全自动尿沉渣分析仪。

关键词：尿沉渣仪器设备评价研究红细胞白细胞皮细胞

Life-Cycle Bearing Capacity for Pre-Stressed T-beams Based on Full-Scale Destructive Test

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Structural Durability & Health Monitoring 2025年第1期19卷 145-166页

作者： Yushan Ye tao gao Liankun Wang Junjie Ma Yingchun Cai Heng Liu Xiaoge Liu China Construction Seventh Engineering Division Corp. Ltd.Zhengzhou450004China School of Water Conservancy and Transportation Zhengzhou UniversityZhengzhou450001China

To investigate the evolution of load-bearing characteristics of pre-stressed beams throughout their service life and to provide a basis for accurately assessing the actual working state of damaged pre-stressed concrete T-beams,destructive tests were conducted on full-scale pre-stressed concrete *** on the measurement and ana-lysis of beam deﬂection,strain,and crack development under various loading levels during the research tests,combined with the veriﬁcation coefﬁcient indicators speciﬁed in the codes,the veriﬁcation coefﬁcients of bridges at different stages of damage can be *** results indicate that the T-beams experience complete,incom-plete linear,and non-linear stages during the destructive test *** the complete linear elastic stage,both the deﬂection and bottom strain veriﬁcation coefﬁcients comply with the speciﬁcations,indicating a good structural load-bearing capacity no longer adheres to the code’s *** the non-linear stage,both coefﬁcients exhi-bit a sharp increase,resulting in a further decrease in the structure’s load-bearing *** to the pro-visions of the current code,the beam can be in the incomplete linear stage when both values fall within the code’s speciﬁed *** strain veriﬁcation coefﬁcient sourced from the compression zone at the bottom of theﬂange is not recommended for assessing the bridge’s load-bearing capacity.

关键词： Pre-stressed T-beams whole process destructive test bearing capacity veriﬁcation coefﬁcient

Effect of order–disorder transition on thermodynamic and electronic properties of σ and χ phases in W–Re alloy: the first-principles calculation

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Tungsten 2025年第1期7卷 195-213页

作者： Zhi-Peng Zhu Dian Jia William Yi Wang Jun-Lei Yin Xing-Yu gao shu-Feng Yang Hai-Feng Song Jin-Shan Li State Key Laboratory of Solidification Processing Northwestern Polytechnical University Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

The Tungsten-Rhenium(W-Re) alloys,celebrated for their high melting point,strength at elevated temperatures,electrical resistivity,and radiation resistance,have been widely utilized in high-temperature components,aerospace,electronics,and nuclear *** constituents of the topologically close-packed(TCP) phases,the sigma phase(σ) and chi phase(χ) formed within W-Re alloys wield considerable influence on the mechanical properties and the stability of the *** calculations were utilized in the present work to explore the structural,thermodynamic,and electronic properties of both ordered and disordered configurations within the σ and χ phases,culminating in a systematic elucidation of the higher phase stability exhibited by the ordered *** is found that the bulk modulus of these two phases is directly proportional to the concentration of Re in the alloy,while the equilibrium volume is inversely *** thermodynamic parameters of the σ and χ phases are calculated via the mean-field potential *** similar trends observed in the isobaric heat capacity,enthalpy increment,and entropy change curves for these two phases suggest they possess comparable thermodynamic *** is noteworthy that the contribution of ionic vibrations predominantly affects the isobaric heat capacity,while the contribution of thermal electronic excitations increases linearly with *** the structure and thermodynamic properties of TCP phases in W-Re alloys at low temperatures has profound significance for optimizing material performance,microstructures features,establishing theoretical foundations,and predicting material behavior.

关键词： First-principles calculations Phase stability TCP phases Thermodynamic properties W–Re alloy

Bulging Performance and Quality Control of Aluminum Alloy Tailor-welded Overlapping Sheets Based on Interface Friction

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 258-264页

作者： gao Tiejun gao Bowen LI Weijie ZHANG Jiabin College of Aerospace Engineering Shenyang Aerospace UniversityShenyang 110136China Shenyang Aerospace Xinguang Group Co.L td. Shenyang 110043China

In order to solve the problem of poor formability caused by different materials and properties in the process of tailor-welded sheets forming,a forming method was proposed to change the stress state of tailor-welded sheets by covering the tailor-welded sheets with better plastic properties overlapping *** the same time,the interface friction effect between the overlapping and tailor-welded sheets was utilized to control the stress magnitude and further improve the formability and quality of the tailor-welded *** this work,the bulging process of the tailor-welded overlapping sheets was taken as the research *** alloy tailor-welded overlapping sheets bulging specimens were studied by a combination of finite element analysis and experimental *** results show that the appropriate use of interface friction between tailor-welded and overlapping sheets can improve the formability of tailor-welded sheets and control the flow of weld seam to improve the forming *** increasing the interface friction coefficient on the side of tailor-welded sheets with higher strength and decreasing that on the side of tailor-welded sheets with lower strength,the deformation of the tailor-welded sheets are more uniform,the offset of the weld seam is minimal,the limit bulging height is maximal,and the forming quality is optimal.

关键词： tailor-welded sheets overlapping sheet bulging interface friction weld seam stress

Construction Concept and Innovative Practices of Virtual Power Plants in Megacities Under Electricity Market Environment

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Dianwang Jishu/Power System Technology 2025年第1期49卷 103-112页

作者： Tang, Jun gao, Hongchao Yu, tao Kang, Chongqing State Grid Shanghai Municipal Electric Power Company Pudong New Area Shanghai 200122 China National Key Laboratory of New Power System Operation and Control [Tsinghua University Haidian District Beijing 100084 China

With the accelerated construction of new power systems, the Virtual Power Plant (VPP), a key component of the new energy framework, provides critical support for safe supply, energy conservation, and emission reduction for power systems. However, the increasingly diverse technological forms and application scenarios of VPPs present challenges for standardization in large-scale development. A timely summary and generalization of VPP development principles, construction pathways, and technical practices can promote technical synergy and drive industry growth. This paper takes the VPP in a megacity as a typical use case. It thoroughly discusses the top-level design of the VPP by reviewing and analyzing four perspectives of form, policy, market, and standards. Secondly, this paper examines a multi-spatiotemporal regulation technology system for VPPs from three dimensions precise response, regional coordination, and fast regulation, which supports the normalized operation of Shanghai’s VPP. Then, this paper introduces the large-scale demonstration outcomes of Shanghai’s VPP, offering a valuable reference for development constructions and innovative practices of VPPs at the megacity scale. Finally, by analyzing the construction and operational outlook of Shanghai's VPP, this paper distills a clear pathway for its future development. © 2025 Power System Technology Press. All rights reserved.

关键词： Virtual Power Plants

Catalytic atroposelective synthesis of indolyl quinazolinones bearing N-N/C-C diaxes

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Science China Chemistry 2025年

作者： Ning-Yi Wang shuo gao Zhu-Di shu Bei-Bei Cheng Chun Ma Yu-Chen Zhang Feng Shi Research Center of Chiral Functional Heterocycles School of Chemistry and Materials Science Jiangsu Normal University School of Petrochemical Engineering Changzhou University School of Chemistry and Chemical Engineering Henan Normal University

The first catalytic atroposelective synthesis of indole derivatives bearing N-N/C-C diaxes has been established by the strategy of de novo ring formation. By this strategy, various indolyl quinazolinones bearing vicinal N-N/C-C diaxes were synthesized in high yields with overall good diastereoselectivities and excellent enantioselectivities via chiral phosphoric acid-catalyzed onepot asymmetric formal (5+1) cycloaddition/oxidation reaction. Moreover, such indolyl quinazolinones bearing vicinal N-N/CC diaxes have good configurational stability and could be converted into new chiral ligands with applications in asymmetric catalysis. Therefore, this work not only offered a new member for the family of diaxial atropisomers, but also provided a powerful strategy for catalytic asymmetric synthesis of atropisomers bearing N-N/C-C diaxes.

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