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Chinese Journal of Structural Chemistry 2005年第8期24卷 930-934页

作者： ZHANG Dong-Heng du jian-long HAN Ling-Qin SUN Wen-Hua Key Laboratory of Engineering Plastics Institute of Chemistry The Chinese Academy of Sciences Beijing 100080 State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou 350002 China College of Chemistry & Environmental Science Hebei UniversityChina Baoding 071002

The title nickel complex （C34H3oCl2N2NiO4, Mr = 660.21） has been synthesized and its crystal structure was determined by single-crystal X-ray structure analysis. It crystallizes in the monoclinic system, space group P21/n with a = 11.026（8）, b = 11.491（8）, c = 12.119（9） A°, β=91.328（13）°, Z= 2, V= 1535.0（19） ,A°^3, Dc = 1.428 g/cm^3, F（000） = 684 andμ（MoKa） = 0.848 mm^-1 The structure was refined to R = 0.0544 for 1813 observed reflections with I 〉 2σ（I） and wR =0.0867 for 3132 unique reflections. The molecule of the complex is high symmetrical. Ni（Ⅱ） atom is located in the symmetric center and coordinated to two phenolic oxygen and two imino nitrogen atoms, forming two six-membered rings. Upon activation with methylaluminoxane （MAO）, it is active for ethylene oligomerization.

关键词： nickel complex salicylaldimine ethylene oligomerization

Rational design and synthesis of a uranyl-organic hybrid for X-ray scintillation

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Chinese Journal of Structural Chemistry 2024年第5期43卷 14-17页

作者： Jingqi Ma Huangjie Lu Junpu Yang Liangwei Yang jian-Qiang Wang Xian-long du jian Lin Key Laboratory of Interfacial Physics and Technology Shanghai Institute of Applied PhysicsChinese Academy of Sciences2019 Jialuo RoadShanghai201800China School of Nuclear Science and Technology Xi'an Jiaotong UniversityNo.28West Xianning RoadXi'an710049China University of Chinese Academy of Sciences No.19(A)Yuquan RoadShijingshan DistrictBeijing100049China State Key Laboratory of Radiation Medicine and Protection Soochow UniversitySuzhouJiangsu215123China

Uranyl-organic hybrids,which are assembled from uranyl cations or polynuclear clusters and organic ligands,have gathered tremendous attention driven by their vast array of synthetically accessible structures for customizing their functionality[1].A plethora of uranyl-organic hybrids with their dimensions ranging from OD clusters,1D chains,2D layers and 3D frameworks have been documented in diverse fields including storage,separation,catalysis and sensing[2].

关键词： synthesis dimensions chains

On entire solutions of some Fermat type differential-difference equations

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 69-88页

作者： long jian-ren QIN Da-zhuan School of Mathematical Sciences Guizhou Normal UniversityGuiyang 550025China

On one hand,we study the existence of transcendental entire solutions with finite order of the Fermat type difference *** the other hand,we also investigate the existence and growth of solutions of nonlinear different... 详细信息

关键词： entire solutions differential-difference equations existence finite order

Generalized Inverses and Units in a Unitary Ring

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Acta Mathematica Sinica,English Series 2024年第4期40卷 1000-1014页

作者： Yu Kun ZHOU jian long CHEN School of Mathematics Southeast UniversityNanjing 210096P.R.China

Let R be a unitary ring and a,b∈R with ab=*** find the 2/3 property of Drazin invertibility:if any two of a,b and a+b are Drazin invertible,then so is the third ***,we combine the 2/3 property of Drazin invertibility to characterize the existence of generalized inverses by means of *** applications,the need for two invertible morphisms used by You and Chen to characterize the group invertibility of a sum of morphisms is reduced to that for one invertible morphism,and the existence and expression of the inverse along a product of two regular elements are obtained,which generalizes the main result of Mary and Patricio(2016)about the group inverse of a product.

关键词： Leftπ-regular element stronglyπ-regular element group inverse Drazin inverse inverse along an element

Facilitating stable gene integration expression and copy number amplification in Bacillus subtilis through a reversible homologous recombination switch

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Synthetic and Systems Biotechnology 2024年第3期9卷 577-585页

作者： Haoyu Guo Rongzhen Tian Yaokang Wu Xueqin Lv jianghua Li long Liu a b Guocheng du jian Chen Yanfeng Liu Key Laboratory of Carbohydrate Chemistry and Biotechnology Ministry of EducationSchool of BiotechnologyJiangnan UniversityWuxi214122China Science Center for Future Foods Jiangnan UniversityWuxi214122China Engineering Research Center of Ministry of Education on Food Synthetic Biotechnology Jiangnan UniversityWuxi214122China jiangsu Province Engineering Research Center of Food Synthetic Biotechnology Jiangnan UniversityWuxi214122China

Strengthening the expression level of integrated genes on the genome is crucial for consistently expressing key enzymes in microbial cell factories for efficient bioproduction in synthetic *** comparison to plasmid-based multi-copy expression,the utilization of chromosomal multi-copy genes offers increased stability of expression level,diminishes the metabolic burden on host cells,and enhances overall genetic *** this study,we developed the“BacAmp”,a stabilized gene integration expression and copy number amplification system for high-level expression in Bacillus subtilis,which was achieved by employing a combination of repressor and non-natural amino acids(ncAA)-dependent expression system to create a reversible switch to control the key gene recA for homologous *** the reversible switch is turned on,genome editing and gene amplification can be ***,the reversible switch was turned off therefore stabilizing the gene copy *** stabilized gene amplification system marked by green fluorescent protein,achieved a 3-fold increase in gene expression by gene amplification and maintained the average gene copy number at 10 after 110 *** we implemented the gene amplification system for the regulation of N-acetylneuraminic acid(NeuAc)synthesis,the copy number of the critical gene increased to an average of 7.7,which yielded a 1.3-fold NeuAc *** research provides a new avenue for gene expression in synthetic biology and can be applied in metabolic engineering in ***.

关键词： Bacillus subtilis Stabilized gene amplification system Homologous recombination recA

A novel and promising engineering application of carbon dots:Enhancing the chloride binding performance of cement

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Chinese Chemical Letters 2024年第6期35卷 409-416页

作者： Wu-jian long Yang Yu Chuang He Guangdong Provincial Key Laboratory of durability for Marine Civil Engineering Key Lab of Coastal Urban Resilient InfrastructureMOECollege of Civil and Transportation EngineeringShenzhen UniversityShenzhen 518060China

Corrosion of reinforcement induced by chloride invasion is extensively considered as the dominating deterioration mechanism of reinforced concrete(RC)structures,leading to serious safety hazards and tremendous economic ***,it still lacks well dispersive and cost-efficient nanomaterials to improve the anti-chloride-corrosion ability of RC ***,specific carbon dots(CDs)with high dispersity and low cost are deliberately designed,successfully prepared by hydrothermal processing,and then firstly applied to immensely enhance chloride binding performance of cement,thereby contributing to suppressing the corrosion of ***,the tailored CDs are composed of the carbon core with highly crystalline sp^(2)C structures and oxygen-containing groups connecting on the carbon core;The typical equilibrium test confirms that with respect to that of the blank cement paste,the chloride binding capacity of cement paste involving 0.2 wt%(by weight of cement)CDs is increased by 109% after 14-day exposure to 3 mol/L Na Cl solution;according to comprehensive analyses of phase compositions,the chloride binding mechanism of CDs-modified cement is rationally attributed to the fact that the incorporation of CDs advances the formation of calcium silicate hydrate(C-S-H)gels and Friedel's salt(Fs),thus enormously enhancing the physically adsorbed and chemically bound chloride ions of cement *** work not only firstly provides a novel high-dispersity and low-cost nanomaterial toward the durability enhancement of RC structures,but also broadens the application of CDs in the field of engineering,conducing to stimulating their industrialization development.

关键词： Carbon dots Chloride binding Cement Chloride binding mechanism Friedel’s salt

Design and Application of an S-band Fast Radio Bursts Search Pipeline for the Nanshan 26 m Radio Telescope

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Research in Astronomy and Astrophysics 2024年第7期24卷 111-117页

作者： Yan-Ling Liu Mao-Zheng Chen jian Li jian-Ping Yuan Rai Yuen Zhi-Yong Liu Hao Yan Wen-long du Nan-Nan Zhai Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Xinjiang Key Laboratory of Microwave Technology Urumqi 830011China University of Chinese Academy of Sciences Beijing 100049China

Fast radio bursts(FRBs)are among the most studied radio transients in astrophysics,but their origin and radiation mechanism are still *** is a challenge to search for FRB events in a huge amount of observational data with high speed and high *** the rapid advancement of the FRB research process,FRB searching has changed from archive data mining to either long-term monitoring of the repeating FRBs or all-sky surveys with specialized ***,establishing a highly efficient and high quality FRB search pipeline is the primary task in FRB *** learning techniques provide new ideas for FRB search *** have detected radio bursts from FRB 20201124A in the L-band observational data of the Nanshan 26 m radio telescope(NSRT-26m)using the constructed deep learning based search pipeline named dispersed dynamic spectra search(DDSS).Afterwards,we further retrained the deep learning model and applied the DDSS framework to S-band *** this paper,we present the FRB observation system and search pipeline using the S-band *** carried out search experiments,and successfully detected the radio bursts from the magnetar SGR J1935+2145and FRB *** experimental results show that the search pipeline can complete the search efficiently and output the search results with high accuracy.

关键词： radio continuum general-methods data analysis-methods observational

Sparse Modal Decomposition Method Addressing Underdetermined Vortex-Induced Vibration Reconstruction Problem for Marine Risers

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China Ocean Engineering 2024年第2期38卷 285-296页

作者： du Zun-feng ZHU Hai-ming YU jian-xing State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation School of Civil EngineeringTianjin UniversityTianjin 300350China

When investigating the vortex-induced vibration(VIV)of marine risers,extrapolating the dynamic response on the entire length based on limited sensor measurements is a crucial step in both laboratory experiments and fatigue monitoring of real *** problem is conventionally solved using the modal decomposition method,based on the principle that the response can be approximated by a weighted sum of limited vibration ***,the method is not valid when the problem is underdetermined,i.e.,the number of unknown mode weights is more than the number of known *** study proposed a sparse modal decomposition method based on the compressed sensing theory and the Compressive Sampling Matching Pursuit(Co Sa MP)algorithm,exploiting the sparsity of VIV in the modal *** the validation study based on high-order VIV experiment data,the proposed method successfully reconstructed the response using only seven acceleration measurements when the conventional methods failed.A primary advantage of the proposed method is that it offers a completely data-driven approach for the underdetermined VIV reconstruction problem,which is more favorable than existing model-dependent solutions for many practical applications such as riser structural health monitoring.

关键词： motion reconstruction vortex-induced vibration(VIV) marine riser modal decomposition method compressed sensing

Molecular solid solution of lanthanide-titanium-oxo clusters with enhanced photocatalytic hydrogen evolution

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Science China Chemistry 2024年第2期67卷 529-535页

作者： Rong Chen Chao-long Chen Hui Zhang Zi-Han Wang Fu-Li Sun Ming-Hao du Gui-Lin Zhuang Cheng Wang La-Sheng long Lan-Sun Zheng Xiang-jian Kong Collaborative Innovation Centre of Chemistry for Energy Materials State Key Laboratory of Physical Chemistry of Solid Surfaces and Department of Chemistry College of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China College of Chemical Engineering Zhejiang University of TechnologyHangzhou310032China

Molecular solid solutions of metal clusters containing different metal centers with well-defined structures can accurately regulate the HOMO-LUMO gap,but are rarely ***,a series of colorless lanthanide-titanium-oxo clusters Ln_(2)Ti_4(μ_(2)-O)_(2)(μ_(3)-O)_4(Piv)_(10)(THF)_(2)(Ln_(2)Ti_4,Ln = Eu,Gd,Tb,and Ce,HPiv = pivalic acid) were synthesized by the reaction of pivalic acid with Ln(Ac)_(3) and titanium *** light yellow crystal of cluster solid solutions Eu_(2)Ti_(4-x)Cd_(x),containing a mixture of Eu_(2)Ti_4 and Eu_(2)Ti_(3)Cd,was obtained by in situ doping Cd^(2+) and S^(2–).Eu_(2)Ti_(3.92)Cd_(0.08) displays efficient photocatalytic hydrogen evolution activity without a co-catalyst,which is up to 2.6 times that of Eu_(2)Ti_*** time-resolved transient absorption spectroscopy and spin-polarized density functional calculations showed that the enhanced photocatalytic performance of Eu_(2)Ti_(4-x)Cd_(x) can be attributed to the narrower HOMO-LUMO gap and lower LUMO position than that of Eu_(2)Ti_*** studyprovides an in situ doping method to realize the simple preparation of cluster solid solution.

关键词： molecular solid solution lanthanide-titanium-oxo clusters photocatalytic hydrogen evolution

Synergistic Effects of Carbon Nanotube(CNT)and Reduced Graphene Oxide(RGO)on Mechanical and Thermal Properties of ZK61 Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 577-585页

作者： Fanjing Meng Wenbo du Ning Ding jian Sun Xian du Ke Liu Shubo Li College of Materials Science and Engineering Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China

The hybrid of carbon nanotube(CNT)and reduced graphene oxide(RGO)reinforced ZK61 composite was fabricated by a hot extrusion *** with the raw ZK61 alloy and single-reinforced composites,the hybrid-reinforced by RGO+CNT complex exhibited significant enhancements both in mechanical and thermal *** adjusting the proportion of RGO and CNT in ZK61 alloy,the obtained optimum ZK61/(0.06 wt%RGO+0.54 wt%CNT)composite exhibited increase of 25.4%in yield strength,26.5%in ultimate tensile strength,104%in failure strain and 30.4%in thermal conductivity,respectively,in comparison with ZK61 *** superior properties of the nano-hybrid composite are attributed to the synergetic effects of RGO and CNT,leading to a uniform dispersion and integrated structure as well as the enhanced interfacial bonding with *** strengthening ability of RGO and CNT was calculated to quantify their individual contribution to the improvement in mechanical and thermal properties of the ZK61 matrix *** RGO+CNT hybrids provide a promising way to develop Mg matrix composites with impressive performances.

关键词： Mg matrix composite Carbon nanotube Reduced graphene oxide Mechanical performance Thermal conductivity